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pmap.c revision 1.312
      1 /*	$NetBSD: pmap.c,v 1.312 2014/11/08 08:01:34 matt Exp $	*/
      2 
      3 /*
      4  * Copyright 2003 Wasabi Systems, Inc.
      5  * All rights reserved.
      6  *
      7  * Written by Steve C. Woodford for Wasabi Systems, Inc.
      8  *
      9  * Redistribution and use in source and binary forms, with or without
     10  * modification, are permitted provided that the following conditions
     11  * are met:
     12  * 1. Redistributions of source code must retain the above copyright
     13  *    notice, this list of conditions and the following disclaimer.
     14  * 2. Redistributions in binary form must reproduce the above copyright
     15  *    notice, this list of conditions and the following disclaimer in the
     16  *    documentation and/or other materials provided with the distribution.
     17  * 3. All advertising materials mentioning features or use of this software
     18  *    must display the following acknowledgement:
     19  *      This product includes software developed for the NetBSD Project by
     20  *      Wasabi Systems, Inc.
     21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
     22  *    or promote products derived from this software without specific prior
     23  *    written permission.
     24  *
     25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
     26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
     29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     35  * POSSIBILITY OF SUCH DAMAGE.
     36  */
     37 
     38 /*
     39  * Copyright (c) 2002-2003 Wasabi Systems, Inc.
     40  * Copyright (c) 2001 Richard Earnshaw
     41  * Copyright (c) 2001-2002 Christopher Gilbert
     42  * All rights reserved.
     43  *
     44  * 1. Redistributions of source code must retain the above copyright
     45  *    notice, this list of conditions and the following disclaimer.
     46  * 2. Redistributions in binary form must reproduce the above copyright
     47  *    notice, this list of conditions and the following disclaimer in the
     48  *    documentation and/or other materials provided with the distribution.
     49  * 3. The name of the company nor the name of the author may be used to
     50  *    endorse or promote products derived from this software without specific
     51  *    prior written permission.
     52  *
     53  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
     54  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
     55  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     56  * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
     57  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     58  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
     59  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     63  * SUCH DAMAGE.
     64  */
     65 
     66 /*-
     67  * Copyright (c) 1999 The NetBSD Foundation, Inc.
     68  * All rights reserved.
     69  *
     70  * This code is derived from software contributed to The NetBSD Foundation
     71  * by Charles M. Hannum.
     72  *
     73  * Redistribution and use in source and binary forms, with or without
     74  * modification, are permitted provided that the following conditions
     75  * are met:
     76  * 1. Redistributions of source code must retain the above copyright
     77  *    notice, this list of conditions and the following disclaimer.
     78  * 2. Redistributions in binary form must reproduce the above copyright
     79  *    notice, this list of conditions and the following disclaimer in the
     80  *    documentation and/or other materials provided with the distribution.
     81  *
     82  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     83  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     84  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     85  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     86  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     87  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     88  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     89  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     90  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     91  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     92  * POSSIBILITY OF SUCH DAMAGE.
     93  */
     94 
     95 /*
     96  * Copyright (c) 1994-1998 Mark Brinicombe.
     97  * Copyright (c) 1994 Brini.
     98  * All rights reserved.
     99  *
    100  * This code is derived from software written for Brini by Mark Brinicombe
    101  *
    102  * Redistribution and use in source and binary forms, with or without
    103  * modification, are permitted provided that the following conditions
    104  * are met:
    105  * 1. Redistributions of source code must retain the above copyright
    106  *    notice, this list of conditions and the following disclaimer.
    107  * 2. Redistributions in binary form must reproduce the above copyright
    108  *    notice, this list of conditions and the following disclaimer in the
    109  *    documentation and/or other materials provided with the distribution.
    110  * 3. All advertising materials mentioning features or use of this software
    111  *    must display the following acknowledgement:
    112  *	This product includes software developed by Mark Brinicombe.
    113  * 4. The name of the author may not be used to endorse or promote products
    114  *    derived from this software without specific prior written permission.
    115  *
    116  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
    117  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
    118  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
    119  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
    120  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
    121  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    122  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    123  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    124  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
    125  *
    126  * RiscBSD kernel project
    127  *
    128  * pmap.c
    129  *
    130  * Machine dependent vm stuff
    131  *
    132  * Created      : 20/09/94
    133  */
    134 
    135 /*
    136  * armv6 and VIPT cache support by 3am Software Foundry,
    137  * Copyright (c) 2007 Microsoft
    138  */
    139 
    140 /*
    141  * Performance improvements, UVM changes, overhauls and part-rewrites
    142  * were contributed by Neil A. Carson <neil (at) causality.com>.
    143  */
    144 
    145 /*
    146  * Overhauled again to speedup the pmap, use MMU Domains so that L1 tables
    147  * can be shared, and re-work the KVM layout, by Steve Woodford of Wasabi
    148  * Systems, Inc.
    149  *
    150  * There are still a few things outstanding at this time:
    151  *
    152  *   - There are some unresolved issues for MP systems:
    153  *
    154  *     o The L1 metadata needs a lock, or more specifically, some places
    155  *       need to acquire an exclusive lock when modifying L1 translation
    156  *       table entries.
    157  *
    158  *     o When one cpu modifies an L1 entry, and that L1 table is also
    159  *       being used by another cpu, then the latter will need to be told
    160  *       that a tlb invalidation may be necessary. (But only if the old
    161  *       domain number in the L1 entry being over-written is currently
    162  *       the active domain on that cpu). I guess there are lots more tlb
    163  *       shootdown issues too...
    164  *
    165  *     o If the vector_page is at 0x00000000 instead of in kernel VA space,
    166  *       then MP systems will lose big-time because of the MMU domain hack.
    167  *       The only way this can be solved (apart from moving the vector
    168  *       page to 0xffff0000) is to reserve the first 1MB of user address
    169  *       space for kernel use only. This would require re-linking all
    170  *       applications so that the text section starts above this 1MB
    171  *       boundary.
    172  *
    173  *     o Tracking which VM space is resident in the cache/tlb has not yet
    174  *       been implemented for MP systems.
    175  *
    176  *     o Finally, there is a pathological condition where two cpus running
    177  *       two separate processes (not lwps) which happen to share an L1
    178  *       can get into a fight over one or more L1 entries. This will result
    179  *       in a significant slow-down if both processes are in tight loops.
    180  */
    181 
    182 /*
    183  * Special compilation symbols
    184  * PMAP_DEBUG		- Build in pmap_debug_level code
    185  */
    186 
    187 /* Include header files */
    188 
    189 #include "opt_cpuoptions.h"
    190 #include "opt_pmap_debug.h"
    191 #include "opt_ddb.h"
    192 #include "opt_lockdebug.h"
    193 #include "opt_multiprocessor.h"
    194 
    195 #ifdef MULTIPROCESSOR
    196 #define _INTR_PRIVATE
    197 #endif
    198 
    199 #include <sys/param.h>
    200 #include <sys/types.h>
    201 #include <sys/kernel.h>
    202 #include <sys/systm.h>
    203 #include <sys/proc.h>
    204 #include <sys/intr.h>
    205 #include <sys/pool.h>
    206 #include <sys/kmem.h>
    207 #include <sys/cdefs.h>
    208 #include <sys/cpu.h>
    209 #include <sys/sysctl.h>
    210 #include <sys/bus.h>
    211 #include <sys/atomic.h>
    212 #include <sys/kernhist.h>
    213 
    214 #include <uvm/uvm.h>
    215 
    216 #include <arm/locore.h>
    217 
    218 __KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.312 2014/11/08 08:01:34 matt Exp $");
    219 
    220 //#define PMAP_DEBUG
    221 #ifdef PMAP_DEBUG
    222 
    223 /* XXX need to get rid of all refs to this */
    224 int pmap_debug_level = 0;
    225 
    226 /*
    227  * for switching to potentially finer grained debugging
    228  */
    229 #define	PDB_FOLLOW	0x0001
    230 #define	PDB_INIT	0x0002
    231 #define	PDB_ENTER	0x0004
    232 #define	PDB_REMOVE	0x0008
    233 #define	PDB_CREATE	0x0010
    234 #define	PDB_PTPAGE	0x0020
    235 #define	PDB_GROWKERN	0x0040
    236 #define	PDB_BITS	0x0080
    237 #define	PDB_COLLECT	0x0100
    238 #define	PDB_PROTECT	0x0200
    239 #define	PDB_MAP_L1	0x0400
    240 #define	PDB_BOOTSTRAP	0x1000
    241 #define	PDB_PARANOIA	0x2000
    242 #define	PDB_WIRING	0x4000
    243 #define	PDB_PVDUMP	0x8000
    244 #define	PDB_VAC		0x10000
    245 #define	PDB_KENTER	0x20000
    246 #define	PDB_KREMOVE	0x40000
    247 #define	PDB_EXEC	0x80000
    248 
    249 int debugmap = 1;
    250 int pmapdebug = 0;
    251 #define	NPDEBUG(_lev_,_stat_) \
    252 	if (pmapdebug & (_lev_)) \
    253         	((_stat_))
    254 
    255 #else	/* PMAP_DEBUG */
    256 #define NPDEBUG(_lev_,_stat_) /* Nothing */
    257 #endif	/* PMAP_DEBUG */
    258 
    259 /*
    260  * pmap_kernel() points here
    261  */
    262 static struct pmap	kernel_pmap_store = {
    263 #ifndef ARM_MMU_EXTENDED
    264 	.pm_activated = true,
    265 	.pm_domain = PMAP_DOMAIN_KERNEL,
    266 	.pm_cstate.cs_all = PMAP_CACHE_STATE_ALL,
    267 #endif
    268 };
    269 struct pmap * const	kernel_pmap_ptr = &kernel_pmap_store;
    270 #undef pmap_kernel
    271 #define pmap_kernel()	(&kernel_pmap_store)
    272 #ifdef PMAP_NEED_ALLOC_POOLPAGE
    273 int			arm_poolpage_vmfreelist = VM_FREELIST_DEFAULT;
    274 #endif
    275 
    276 /*
    277  * Pool and cache that pmap structures are allocated from.
    278  * We use a cache to avoid clearing the pm_l2[] array (1KB)
    279  * in pmap_create().
    280  */
    281 static struct pool_cache pmap_cache;
    282 static LIST_HEAD(, pmap) pmap_pmaps;
    283 
    284 /*
    285  * Pool of PV structures
    286  */
    287 static struct pool pmap_pv_pool;
    288 static void *pmap_bootstrap_pv_page_alloc(struct pool *, int);
    289 static void pmap_bootstrap_pv_page_free(struct pool *, void *);
    290 static struct pool_allocator pmap_bootstrap_pv_allocator = {
    291 	pmap_bootstrap_pv_page_alloc, pmap_bootstrap_pv_page_free
    292 };
    293 
    294 /*
    295  * Pool and cache of l2_dtable structures.
    296  * We use a cache to avoid clearing the structures when they're
    297  * allocated. (196 bytes)
    298  */
    299 static struct pool_cache pmap_l2dtable_cache;
    300 static vaddr_t pmap_kernel_l2dtable_kva;
    301 
    302 /*
    303  * Pool and cache of L2 page descriptors.
    304  * We use a cache to avoid clearing the descriptor table
    305  * when they're allocated. (1KB)
    306  */
    307 static struct pool_cache pmap_l2ptp_cache;
    308 static vaddr_t pmap_kernel_l2ptp_kva;
    309 static paddr_t pmap_kernel_l2ptp_phys;
    310 
    311 #ifdef PMAPCOUNTERS
    312 #define	PMAP_EVCNT_INITIALIZER(name) \
    313 	EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "pmap", name)
    314 
    315 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
    316 static struct evcnt pmap_ev_vac_clean_one =
    317    PMAP_EVCNT_INITIALIZER("clean page (1 color)");
    318 static struct evcnt pmap_ev_vac_flush_one =
    319    PMAP_EVCNT_INITIALIZER("flush page (1 color)");
    320 static struct evcnt pmap_ev_vac_flush_lots =
    321    PMAP_EVCNT_INITIALIZER("flush page (2+ colors)");
    322 static struct evcnt pmap_ev_vac_flush_lots2 =
    323    PMAP_EVCNT_INITIALIZER("flush page (2+ colors, kmpage)");
    324 EVCNT_ATTACH_STATIC(pmap_ev_vac_clean_one);
    325 EVCNT_ATTACH_STATIC(pmap_ev_vac_flush_one);
    326 EVCNT_ATTACH_STATIC(pmap_ev_vac_flush_lots);
    327 EVCNT_ATTACH_STATIC(pmap_ev_vac_flush_lots2);
    328 
    329 static struct evcnt pmap_ev_vac_color_new =
    330    PMAP_EVCNT_INITIALIZER("new page color");
    331 static struct evcnt pmap_ev_vac_color_reuse =
    332    PMAP_EVCNT_INITIALIZER("ok first page color");
    333 static struct evcnt pmap_ev_vac_color_ok =
    334    PMAP_EVCNT_INITIALIZER("ok page color");
    335 static struct evcnt pmap_ev_vac_color_blind =
    336    PMAP_EVCNT_INITIALIZER("blind page color");
    337 static struct evcnt pmap_ev_vac_color_change =
    338    PMAP_EVCNT_INITIALIZER("change page color");
    339 static struct evcnt pmap_ev_vac_color_erase =
    340    PMAP_EVCNT_INITIALIZER("erase page color");
    341 static struct evcnt pmap_ev_vac_color_none =
    342    PMAP_EVCNT_INITIALIZER("no page color");
    343 static struct evcnt pmap_ev_vac_color_restore =
    344    PMAP_EVCNT_INITIALIZER("restore page color");
    345 
    346 EVCNT_ATTACH_STATIC(pmap_ev_vac_color_new);
    347 EVCNT_ATTACH_STATIC(pmap_ev_vac_color_reuse);
    348 EVCNT_ATTACH_STATIC(pmap_ev_vac_color_ok);
    349 EVCNT_ATTACH_STATIC(pmap_ev_vac_color_blind);
    350 EVCNT_ATTACH_STATIC(pmap_ev_vac_color_change);
    351 EVCNT_ATTACH_STATIC(pmap_ev_vac_color_erase);
    352 EVCNT_ATTACH_STATIC(pmap_ev_vac_color_none);
    353 EVCNT_ATTACH_STATIC(pmap_ev_vac_color_restore);
    354 #endif
    355 
    356 static struct evcnt pmap_ev_mappings =
    357    PMAP_EVCNT_INITIALIZER("pages mapped");
    358 static struct evcnt pmap_ev_unmappings =
    359    PMAP_EVCNT_INITIALIZER("pages unmapped");
    360 static struct evcnt pmap_ev_remappings =
    361    PMAP_EVCNT_INITIALIZER("pages remapped");
    362 
    363 EVCNT_ATTACH_STATIC(pmap_ev_mappings);
    364 EVCNT_ATTACH_STATIC(pmap_ev_unmappings);
    365 EVCNT_ATTACH_STATIC(pmap_ev_remappings);
    366 
    367 static struct evcnt pmap_ev_kernel_mappings =
    368    PMAP_EVCNT_INITIALIZER("kernel pages mapped");
    369 static struct evcnt pmap_ev_kernel_unmappings =
    370    PMAP_EVCNT_INITIALIZER("kernel pages unmapped");
    371 static struct evcnt pmap_ev_kernel_remappings =
    372    PMAP_EVCNT_INITIALIZER("kernel pages remapped");
    373 
    374 EVCNT_ATTACH_STATIC(pmap_ev_kernel_mappings);
    375 EVCNT_ATTACH_STATIC(pmap_ev_kernel_unmappings);
    376 EVCNT_ATTACH_STATIC(pmap_ev_kernel_remappings);
    377 
    378 static struct evcnt pmap_ev_kenter_mappings =
    379    PMAP_EVCNT_INITIALIZER("kenter pages mapped");
    380 static struct evcnt pmap_ev_kenter_unmappings =
    381    PMAP_EVCNT_INITIALIZER("kenter pages unmapped");
    382 static struct evcnt pmap_ev_kenter_remappings =
    383    PMAP_EVCNT_INITIALIZER("kenter pages remapped");
    384 static struct evcnt pmap_ev_pt_mappings =
    385    PMAP_EVCNT_INITIALIZER("page table pages mapped");
    386 
    387 EVCNT_ATTACH_STATIC(pmap_ev_kenter_mappings);
    388 EVCNT_ATTACH_STATIC(pmap_ev_kenter_unmappings);
    389 EVCNT_ATTACH_STATIC(pmap_ev_kenter_remappings);
    390 EVCNT_ATTACH_STATIC(pmap_ev_pt_mappings);
    391 
    392 static struct evcnt pmap_ev_fixup_mod =
    393    PMAP_EVCNT_INITIALIZER("page modification emulations");
    394 static struct evcnt pmap_ev_fixup_ref =
    395    PMAP_EVCNT_INITIALIZER("page reference emulations");
    396 static struct evcnt pmap_ev_fixup_exec =
    397    PMAP_EVCNT_INITIALIZER("exec pages fixed up");
    398 static struct evcnt pmap_ev_fixup_pdes =
    399    PMAP_EVCNT_INITIALIZER("pdes fixed up");
    400 #ifndef ARM_MMU_EXTENDED
    401 static struct evcnt pmap_ev_fixup_ptesync =
    402    PMAP_EVCNT_INITIALIZER("ptesync fixed");
    403 #endif
    404 
    405 EVCNT_ATTACH_STATIC(pmap_ev_fixup_mod);
    406 EVCNT_ATTACH_STATIC(pmap_ev_fixup_ref);
    407 EVCNT_ATTACH_STATIC(pmap_ev_fixup_exec);
    408 EVCNT_ATTACH_STATIC(pmap_ev_fixup_pdes);
    409 #ifndef ARM_MMU_EXTENDED
    410 EVCNT_ATTACH_STATIC(pmap_ev_fixup_ptesync);
    411 #endif
    412 
    413 #ifdef PMAP_CACHE_VIPT
    414 static struct evcnt pmap_ev_exec_mappings =
    415    PMAP_EVCNT_INITIALIZER("exec pages mapped");
    416 static struct evcnt pmap_ev_exec_cached =
    417    PMAP_EVCNT_INITIALIZER("exec pages cached");
    418 
    419 EVCNT_ATTACH_STATIC(pmap_ev_exec_mappings);
    420 EVCNT_ATTACH_STATIC(pmap_ev_exec_cached);
    421 
    422 static struct evcnt pmap_ev_exec_synced =
    423    PMAP_EVCNT_INITIALIZER("exec pages synced");
    424 static struct evcnt pmap_ev_exec_synced_map =
    425    PMAP_EVCNT_INITIALIZER("exec pages synced (MP)");
    426 #ifndef ARM_MMU_EXTENDED
    427 static struct evcnt pmap_ev_exec_synced_unmap =
    428    PMAP_EVCNT_INITIALIZER("exec pages synced (UM)");
    429 static struct evcnt pmap_ev_exec_synced_remap =
    430    PMAP_EVCNT_INITIALIZER("exec pages synced (RM)");
    431 static struct evcnt pmap_ev_exec_synced_clearbit =
    432    PMAP_EVCNT_INITIALIZER("exec pages synced (DG)");
    433 static struct evcnt pmap_ev_exec_synced_kremove =
    434    PMAP_EVCNT_INITIALIZER("exec pages synced (KU)");
    435 #endif
    436 
    437 EVCNT_ATTACH_STATIC(pmap_ev_exec_synced);
    438 EVCNT_ATTACH_STATIC(pmap_ev_exec_synced_map);
    439 #ifndef ARM_MMU_EXTENDED
    440 EVCNT_ATTACH_STATIC(pmap_ev_exec_synced_unmap);
    441 EVCNT_ATTACH_STATIC(pmap_ev_exec_synced_remap);
    442 EVCNT_ATTACH_STATIC(pmap_ev_exec_synced_clearbit);
    443 EVCNT_ATTACH_STATIC(pmap_ev_exec_synced_kremove);
    444 #endif
    445 
    446 static struct evcnt pmap_ev_exec_discarded_unmap =
    447    PMAP_EVCNT_INITIALIZER("exec pages discarded (UM)");
    448 static struct evcnt pmap_ev_exec_discarded_zero =
    449    PMAP_EVCNT_INITIALIZER("exec pages discarded (ZP)");
    450 static struct evcnt pmap_ev_exec_discarded_copy =
    451    PMAP_EVCNT_INITIALIZER("exec pages discarded (CP)");
    452 static struct evcnt pmap_ev_exec_discarded_page_protect =
    453    PMAP_EVCNT_INITIALIZER("exec pages discarded (PP)");
    454 static struct evcnt pmap_ev_exec_discarded_clearbit =
    455    PMAP_EVCNT_INITIALIZER("exec pages discarded (DG)");
    456 static struct evcnt pmap_ev_exec_discarded_kremove =
    457    PMAP_EVCNT_INITIALIZER("exec pages discarded (KU)");
    458 #ifdef ARM_MMU_EXTENDED
    459 static struct evcnt pmap_ev_exec_discarded_modfixup =
    460    PMAP_EVCNT_INITIALIZER("exec pages discarded (MF)");
    461 #endif
    462 
    463 EVCNT_ATTACH_STATIC(pmap_ev_exec_discarded_unmap);
    464 EVCNT_ATTACH_STATIC(pmap_ev_exec_discarded_zero);
    465 EVCNT_ATTACH_STATIC(pmap_ev_exec_discarded_copy);
    466 EVCNT_ATTACH_STATIC(pmap_ev_exec_discarded_page_protect);
    467 EVCNT_ATTACH_STATIC(pmap_ev_exec_discarded_clearbit);
    468 EVCNT_ATTACH_STATIC(pmap_ev_exec_discarded_kremove);
    469 #ifdef ARM_MMU_EXTENDED
    470 EVCNT_ATTACH_STATIC(pmap_ev_exec_discarded_modfixup);
    471 #endif
    472 #endif /* PMAP_CACHE_VIPT */
    473 
    474 static struct evcnt pmap_ev_updates = PMAP_EVCNT_INITIALIZER("updates");
    475 static struct evcnt pmap_ev_collects = PMAP_EVCNT_INITIALIZER("collects");
    476 static struct evcnt pmap_ev_activations = PMAP_EVCNT_INITIALIZER("activations");
    477 
    478 EVCNT_ATTACH_STATIC(pmap_ev_updates);
    479 EVCNT_ATTACH_STATIC(pmap_ev_collects);
    480 EVCNT_ATTACH_STATIC(pmap_ev_activations);
    481 
    482 #define	PMAPCOUNT(x)	((void)(pmap_ev_##x.ev_count++))
    483 #else
    484 #define	PMAPCOUNT(x)	((void)0)
    485 #endif
    486 
    487 /*
    488  * pmap copy/zero page, and mem(5) hook point
    489  */
    490 static pt_entry_t *csrc_pte, *cdst_pte;
    491 static vaddr_t csrcp, cdstp;
    492 #ifdef MULTIPROCESSOR
    493 static size_t cnptes;
    494 #define	cpu_csrc_pte(o)	(csrc_pte + cnptes * cpu_number() + ((o) >> L2_S_SHIFT))
    495 #define	cpu_cdst_pte(o)	(cdst_pte + cnptes * cpu_number() + ((o) >> L2_S_SHIFT))
    496 #define	cpu_csrcp(o)	(csrcp + L2_S_SIZE * cnptes * cpu_number() + (o))
    497 #define	cpu_cdstp(o)	(cdstp + L2_S_SIZE * cnptes * cpu_number() + (o))
    498 #else
    499 #define	cpu_csrc_pte(o)	(csrc_pte + ((o) >> L2_S_SHIFT))
    500 #define	cpu_cdst_pte(o)	(cdst_pte + ((o) >> L2_S_SHIFT))
    501 #define	cpu_csrcp(o)	(csrcp + (o))
    502 #define	cpu_cdstp(o)	(cdstp + (o))
    503 #endif
    504 vaddr_t memhook;			/* used by mem.c & others */
    505 kmutex_t memlock __cacheline_aligned;	/* used by mem.c & others */
    506 kmutex_t pmap_lock __cacheline_aligned;
    507 extern void *msgbufaddr;
    508 int pmap_kmpages;
    509 /*
    510  * Flag to indicate if pmap_init() has done its thing
    511  */
    512 bool pmap_initialized;
    513 
    514 #if defined(ARM_MMU_EXTENDED) && defined(__HAVE_MM_MD_DIRECT_MAPPED_PHYS)
    515 /*
    516  * Start of direct-mapped memory
    517  */
    518 vaddr_t pmap_directbase = KERNEL_BASE;
    519 #endif
    520 
    521 /*
    522  * Misc. locking data structures
    523  */
    524 
    525 static inline void
    526 pmap_acquire_pmap_lock(pmap_t pm)
    527 {
    528 	if (pm == pmap_kernel()) {
    529 #ifdef MULTIPROCESSOR
    530 		KERNEL_LOCK(1, NULL);
    531 #endif
    532 	} else {
    533 		mutex_enter(pm->pm_lock);
    534 	}
    535 }
    536 
    537 static inline void
    538 pmap_release_pmap_lock(pmap_t pm)
    539 {
    540 	if (pm == pmap_kernel()) {
    541 #ifdef MULTIPROCESSOR
    542 		KERNEL_UNLOCK_ONE(NULL);
    543 #endif
    544 	} else {
    545 		mutex_exit(pm->pm_lock);
    546 	}
    547 }
    548 
    549 static inline void
    550 pmap_acquire_page_lock(struct vm_page_md *md)
    551 {
    552 	mutex_enter(&pmap_lock);
    553 }
    554 
    555 static inline void
    556 pmap_release_page_lock(struct vm_page_md *md)
    557 {
    558 	mutex_exit(&pmap_lock);
    559 }
    560 
    561 #ifdef DIAGNOSTIC
    562 static inline int
    563 pmap_page_locked_p(struct vm_page_md *md)
    564 {
    565 	return mutex_owned(&pmap_lock);
    566 }
    567 #endif
    568 
    569 
    570 /*
    571  * Metadata for L1 translation tables.
    572  */
    573 #ifndef ARM_MMU_EXTENDED
    574 struct l1_ttable {
    575 	/* Entry on the L1 Table list */
    576 	SLIST_ENTRY(l1_ttable) l1_link;
    577 
    578 	/* Entry on the L1 Least Recently Used list */
    579 	TAILQ_ENTRY(l1_ttable) l1_lru;
    580 
    581 	/* Track how many domains are allocated from this L1 */
    582 	volatile u_int l1_domain_use_count;
    583 
    584 	/*
    585 	 * A free-list of domain numbers for this L1.
    586 	 * We avoid using ffs() and a bitmap to track domains since ffs()
    587 	 * is slow on ARM.
    588 	 */
    589 	uint8_t l1_domain_first;
    590 	uint8_t l1_domain_free[PMAP_DOMAINS];
    591 
    592 	/* Physical address of this L1 page table */
    593 	paddr_t l1_physaddr;
    594 
    595 	/* KVA of this L1 page table */
    596 	pd_entry_t *l1_kva;
    597 };
    598 
    599 /*
    600  * L1 Page Tables are tracked using a Least Recently Used list.
    601  *  - New L1s are allocated from the HEAD.
    602  *  - Freed L1s are added to the TAIl.
    603  *  - Recently accessed L1s (where an 'access' is some change to one of
    604  *    the userland pmaps which owns this L1) are moved to the TAIL.
    605  */
    606 static TAILQ_HEAD(, l1_ttable) l1_lru_list;
    607 static kmutex_t l1_lru_lock __cacheline_aligned;
    608 
    609 /*
    610  * A list of all L1 tables
    611  */
    612 static SLIST_HEAD(, l1_ttable) l1_list;
    613 #endif /* ARM_MMU_EXTENDED */
    614 
    615 /*
    616  * The l2_dtable tracks L2_BUCKET_SIZE worth of L1 slots.
    617  *
    618  * This is normally 16MB worth L2 page descriptors for any given pmap.
    619  * Reference counts are maintained for L2 descriptors so they can be
    620  * freed when empty.
    621  */
    622 struct l2_bucket {
    623 	pt_entry_t *l2b_kva;		/* KVA of L2 Descriptor Table */
    624 	paddr_t l2b_pa;			/* Physical address of same */
    625 	u_short l2b_l1slot;		/* This L2 table's L1 index */
    626 	u_short l2b_occupancy;		/* How many active descriptors */
    627 };
    628 
    629 struct l2_dtable {
    630 	/* The number of L2 page descriptors allocated to this l2_dtable */
    631 	u_int l2_occupancy;
    632 
    633 	/* List of L2 page descriptors */
    634 	struct l2_bucket l2_bucket[L2_BUCKET_SIZE];
    635 };
    636 
    637 /*
    638  * Given an L1 table index, calculate the corresponding l2_dtable index
    639  * and bucket index within the l2_dtable.
    640  */
    641 #define L2_BUCKET_XSHIFT	(L2_BUCKET_XLOG2 - L1_S_SHIFT)
    642 #define L2_BUCKET_XFRAME	(~(vaddr_t)0 << L2_BUCKET_XLOG2)
    643 #define L2_BUCKET_IDX(l1slot)	((l1slot) >> L2_BUCKET_XSHIFT)
    644 #define L2_IDX(l1slot)		(L2_BUCKET_IDX(l1slot) >> L2_BUCKET_LOG2)
    645 #define L2_BUCKET(l1slot)	(L2_BUCKET_IDX(l1slot) & (L2_BUCKET_SIZE - 1))
    646 
    647 __CTASSERT(0x100000000ULL == ((uint64_t)L2_SIZE * L2_BUCKET_SIZE * L1_S_SIZE));
    648 __CTASSERT(L2_BUCKET_XFRAME == ~(L2_BUCKET_XSIZE-1));
    649 
    650 /*
    651  * Given a virtual address, this macro returns the
    652  * virtual address required to drop into the next L2 bucket.
    653  */
    654 #define	L2_NEXT_BUCKET_VA(va)	(((va) & L2_BUCKET_XFRAME) + L2_BUCKET_XSIZE)
    655 
    656 /*
    657  * L2 allocation.
    658  */
    659 #define	pmap_alloc_l2_dtable()		\
    660 	    pool_cache_get(&pmap_l2dtable_cache, PR_NOWAIT)
    661 #define	pmap_free_l2_dtable(l2)		\
    662 	    pool_cache_put(&pmap_l2dtable_cache, (l2))
    663 #define pmap_alloc_l2_ptp(pap)		\
    664 	    ((pt_entry_t *)pool_cache_get_paddr(&pmap_l2ptp_cache,\
    665 	    PR_NOWAIT, (pap)))
    666 
    667 /*
    668  * We try to map the page tables write-through, if possible.  However, not
    669  * all CPUs have a write-through cache mode, so on those we have to sync
    670  * the cache when we frob page tables.
    671  *
    672  * We try to evaluate this at compile time, if possible.  However, it's
    673  * not always possible to do that, hence this run-time var.
    674  */
    675 int	pmap_needs_pte_sync;
    676 
    677 /*
    678  * Real definition of pv_entry.
    679  */
    680 struct pv_entry {
    681 	SLIST_ENTRY(pv_entry) pv_link;	/* next pv_entry */
    682 	pmap_t		pv_pmap;        /* pmap where mapping lies */
    683 	vaddr_t		pv_va;          /* virtual address for mapping */
    684 	u_int		pv_flags;       /* flags */
    685 };
    686 
    687 /*
    688  * Macros to determine if a mapping might be resident in the
    689  * instruction/data cache and/or TLB
    690  */
    691 #if ARM_MMU_V7 > 0 && !defined(ARM_MMU_EXTENDED)
    692 /*
    693  * Speculative loads by Cortex cores can cause TLB entries to be filled even if
    694  * there are no explicit accesses, so there may be always be TLB entries to
    695  * flush.  If we used ASIDs then this would not be a problem.
    696  */
    697 #define	PV_BEEN_EXECD(f)  (((f) & PVF_EXEC) == PVF_EXEC)
    698 #define	PV_BEEN_REFD(f)   (true)
    699 #else
    700 #define	PV_BEEN_EXECD(f)  (((f) & (PVF_REF | PVF_EXEC)) == (PVF_REF | PVF_EXEC))
    701 #define	PV_BEEN_REFD(f)   (((f) & PVF_REF) != 0)
    702 #endif
    703 #define	PV_IS_EXEC_P(f)   (((f) & PVF_EXEC) != 0)
    704 #define	PV_IS_KENTRY_P(f) (((f) & PVF_KENTRY) != 0)
    705 #define	PV_IS_WRITE_P(f)  (((f) & PVF_WRITE) != 0)
    706 
    707 /*
    708  * Local prototypes
    709  */
    710 static bool		pmap_set_pt_cache_mode(pd_entry_t *, vaddr_t, size_t);
    711 static void		pmap_alloc_specials(vaddr_t *, int, vaddr_t *,
    712 			    pt_entry_t **);
    713 static bool		pmap_is_current(pmap_t) __unused;
    714 static bool		pmap_is_cached(pmap_t);
    715 static void		pmap_enter_pv(struct vm_page_md *, paddr_t, struct pv_entry *,
    716 			    pmap_t, vaddr_t, u_int);
    717 static struct pv_entry *pmap_find_pv(struct vm_page_md *, pmap_t, vaddr_t);
    718 static struct pv_entry *pmap_remove_pv(struct vm_page_md *, paddr_t, pmap_t, vaddr_t);
    719 static u_int		pmap_modify_pv(struct vm_page_md *, paddr_t, pmap_t, vaddr_t,
    720 			    u_int, u_int);
    721 
    722 static void		pmap_pinit(pmap_t);
    723 static int		pmap_pmap_ctor(void *, void *, int);
    724 
    725 static void		pmap_alloc_l1(pmap_t);
    726 static void		pmap_free_l1(pmap_t);
    727 #ifndef ARM_MMU_EXTENDED
    728 static void		pmap_use_l1(pmap_t);
    729 #endif
    730 
    731 static struct l2_bucket *pmap_get_l2_bucket(pmap_t, vaddr_t);
    732 static struct l2_bucket *pmap_alloc_l2_bucket(pmap_t, vaddr_t);
    733 static void		pmap_free_l2_bucket(pmap_t, struct l2_bucket *, u_int);
    734 static int		pmap_l2ptp_ctor(void *, void *, int);
    735 static int		pmap_l2dtable_ctor(void *, void *, int);
    736 
    737 static void		pmap_vac_me_harder(struct vm_page_md *, paddr_t, pmap_t, vaddr_t);
    738 #ifdef PMAP_CACHE_VIVT
    739 static void		pmap_vac_me_kpmap(struct vm_page_md *, paddr_t, pmap_t, vaddr_t);
    740 static void		pmap_vac_me_user(struct vm_page_md *, paddr_t, pmap_t, vaddr_t);
    741 #endif
    742 
    743 static void		pmap_clearbit(struct vm_page_md *, paddr_t, u_int);
    744 #ifdef PMAP_CACHE_VIVT
    745 static bool		pmap_clean_page(struct vm_page_md *, bool);
    746 #endif
    747 #ifdef PMAP_CACHE_VIPT
    748 static void		pmap_syncicache_page(struct vm_page_md *, paddr_t);
    749 enum pmap_flush_op {
    750 	PMAP_FLUSH_PRIMARY,
    751 	PMAP_FLUSH_SECONDARY,
    752 	PMAP_CLEAN_PRIMARY
    753 };
    754 #ifndef ARM_MMU_EXTENDED
    755 static void		pmap_flush_page(struct vm_page_md *, paddr_t, enum pmap_flush_op);
    756 #endif
    757 #endif
    758 static void		pmap_page_remove(struct vm_page_md *, paddr_t);
    759 
    760 #ifndef ARM_MMU_EXTENDED
    761 static void		pmap_init_l1(struct l1_ttable *, pd_entry_t *);
    762 #endif
    763 static vaddr_t		kernel_pt_lookup(paddr_t);
    764 
    765 
    766 /*
    767  * Misc variables
    768  */
    769 vaddr_t virtual_avail;
    770 vaddr_t virtual_end;
    771 vaddr_t pmap_curmaxkvaddr;
    772 
    773 paddr_t avail_start;
    774 paddr_t avail_end;
    775 
    776 pv_addrqh_t pmap_boot_freeq = SLIST_HEAD_INITIALIZER(&pmap_boot_freeq);
    777 pv_addr_t kernelpages;
    778 pv_addr_t kernel_l1pt;
    779 pv_addr_t systempage;
    780 
    781 /* Function to set the debug level of the pmap code */
    782 
    783 #ifdef PMAP_DEBUG
    784 void
    785 pmap_debug(int level)
    786 {
    787 	pmap_debug_level = level;
    788 	printf("pmap_debug: level=%d\n", pmap_debug_level);
    789 }
    790 #endif	/* PMAP_DEBUG */
    791 
    792 #ifdef PMAP_CACHE_VIPT
    793 #define PMAP_VALIDATE_MD_PAGE(md)	\
    794 	KASSERTMSG(arm_cache_prefer_mask == 0 || (((md)->pvh_attrs & PVF_WRITE) == 0) == ((md)->urw_mappings + (md)->krw_mappings == 0), \
    795 	    "(md) %p: attrs=%#x urw=%u krw=%u", (md), \
    796 	    (md)->pvh_attrs, (md)->urw_mappings, (md)->krw_mappings);
    797 #endif /* PMAP_CACHE_VIPT */
    798 /*
    799  * A bunch of routines to conditionally flush the caches/TLB depending
    800  * on whether the specified pmap actually needs to be flushed at any
    801  * given time.
    802  */
    803 static inline void
    804 pmap_tlb_flush_SE(pmap_t pm, vaddr_t va, u_int flags)
    805 {
    806 #ifdef ARM_MMU_EXTENDED
    807 	pmap_tlb_invalidate_addr(pm, va);
    808 #else
    809 	if (pm->pm_cstate.cs_tlb_id != 0) {
    810 		if (PV_BEEN_EXECD(flags)) {
    811 			cpu_tlb_flushID_SE(va);
    812 		} else if (PV_BEEN_REFD(flags)) {
    813 			cpu_tlb_flushD_SE(va);
    814 		}
    815 	}
    816 #endif /* ARM_MMU_EXTENDED */
    817 }
    818 
    819 static inline void
    820 pmap_tlb_flushID(pmap_t pm)
    821 {
    822 #ifdef ARM_MMU_EXTENDED
    823 	pmap_tlb_asid_release_all(pm);
    824 #else
    825 	if (pm->pm_cstate.cs_tlb_id) {
    826 		cpu_tlb_flushID();
    827 #if ARM_MMU_V7 == 0
    828 		/*
    829 		 * Speculative loads by Cortex cores can cause TLB entries to
    830 		 * be filled even if there are no explicit accesses, so there
    831 		 * may be always be TLB entries to flush.  If we used ASIDs
    832 		 * then it would not be a problem.
    833 		 * This is not true for other CPUs.
    834 		 */
    835 		pm->pm_cstate.cs_tlb = 0;
    836 #endif /* ARM_MMU_V7 */
    837 	}
    838 #endif /* ARM_MMU_EXTENDED */
    839 }
    840 
    841 #ifndef ARM_MMU_EXTENDED
    842 static inline void
    843 pmap_tlb_flushD(pmap_t pm)
    844 {
    845 	if (pm->pm_cstate.cs_tlb_d) {
    846 		cpu_tlb_flushD();
    847 #if ARM_MMU_V7 == 0
    848 		/*
    849 		 * Speculative loads by Cortex cores can cause TLB entries to
    850 		 * be filled even if there are no explicit accesses, so there
    851 		 * may be always be TLB entries to flush.  If we used ASIDs
    852 		 * then it would not be a problem.
    853 		 * This is not true for other CPUs.
    854 		 */
    855 		pm->pm_cstate.cs_tlb_d = 0;
    856 #endif /* ARM_MMU_V7 */
    857 	}
    858 }
    859 #endif /* ARM_MMU_EXTENDED */
    860 
    861 #ifdef PMAP_CACHE_VIVT
    862 static inline void
    863 pmap_cache_wbinv_page(pmap_t pm, vaddr_t va, bool do_inv, u_int flags)
    864 {
    865 	if (PV_BEEN_EXECD(flags) && pm->pm_cstate.cs_cache_id) {
    866 		cpu_idcache_wbinv_range(va, PAGE_SIZE);
    867 	} else if (PV_BEEN_REFD(flags) && pm->pm_cstate.cs_cache_d) {
    868 		if (do_inv) {
    869 			if (flags & PVF_WRITE)
    870 				cpu_dcache_wbinv_range(va, PAGE_SIZE);
    871 			else
    872 				cpu_dcache_inv_range(va, PAGE_SIZE);
    873 		} else if (flags & PVF_WRITE) {
    874 			cpu_dcache_wb_range(va, PAGE_SIZE);
    875 		}
    876 	}
    877 }
    878 
    879 static inline void
    880 pmap_cache_wbinv_all(pmap_t pm, u_int flags)
    881 {
    882 	if (PV_BEEN_EXECD(flags)) {
    883 		if (pm->pm_cstate.cs_cache_id) {
    884 			cpu_idcache_wbinv_all();
    885 			pm->pm_cstate.cs_cache = 0;
    886 		}
    887 	} else if (pm->pm_cstate.cs_cache_d) {
    888 		cpu_dcache_wbinv_all();
    889 		pm->pm_cstate.cs_cache_d = 0;
    890 	}
    891 }
    892 #endif /* PMAP_CACHE_VIVT */
    893 
    894 static inline uint8_t
    895 pmap_domain(pmap_t pm)
    896 {
    897 #ifdef ARM_MMU_EXTENDED
    898 	return pm == pmap_kernel() ? PMAP_DOMAIN_KERNEL : PMAP_DOMAIN_USER;
    899 #else
    900 	return pm->pm_domain;
    901 #endif
    902 }
    903 
    904 static inline pd_entry_t *
    905 pmap_l1_kva(pmap_t pm)
    906 {
    907 #ifdef ARM_MMU_EXTENDED
    908 	return pm->pm_l1;
    909 #else
    910 	return pm->pm_l1->l1_kva;
    911 #endif
    912 }
    913 
    914 static inline bool
    915 pmap_is_current(pmap_t pm)
    916 {
    917 	if (pm == pmap_kernel() || curproc->p_vmspace->vm_map.pmap == pm)
    918 		return true;
    919 
    920 	return false;
    921 }
    922 
    923 static inline bool
    924 pmap_is_cached(pmap_t pm)
    925 {
    926 #ifdef ARM_MMU_EXTENDED
    927 	struct pmap_tlb_info * const ti = cpu_tlb_info(curcpu());
    928 	if (pm == pmap_kernel() || PMAP_PAI_ASIDVALID_P(PMAP_PAI(pm, ti), ti))
    929 		return true;
    930 #else
    931 	struct cpu_info * const ci = curcpu();
    932 	if (pm == pmap_kernel() || ci->ci_pmap_lastuser == NULL
    933 	    || ci->ci_pmap_lastuser == pm)
    934 		return true;
    935 #endif /* ARM_MMU_EXTENDED */
    936 
    937 	return false;
    938 }
    939 
    940 /*
    941  * PTE_SYNC_CURRENT:
    942  *
    943  *     Make sure the pte is written out to RAM.
    944  *     We need to do this for one of two cases:
    945  *       - We're dealing with the kernel pmap
    946  *       - There is no pmap active in the cache/tlb.
    947  *       - The specified pmap is 'active' in the cache/tlb.
    948  */
    949 #ifdef PMAP_INCLUDE_PTE_SYNC
    950 #define	PTE_SYNC_CURRENT(pm, ptep)	\
    951 do {					\
    952 	if (PMAP_NEEDS_PTE_SYNC && 	\
    953 	    pmap_is_cached(pm))		\
    954 		PTE_SYNC(ptep);		\
    955 } while (/*CONSTCOND*/0)
    956 #else
    957 #define	PTE_SYNC_CURRENT(pm, ptep)	/* nothing */
    958 #endif
    959 
    960 /*
    961  * main pv_entry manipulation functions:
    962  *   pmap_enter_pv: enter a mapping onto a vm_page list
    963  *   pmap_remove_pv: remove a mapping from a vm_page list
    964  *
    965  * NOTE: pmap_enter_pv expects to lock the pvh itself
    966  *       pmap_remove_pv expects the caller to lock the pvh before calling
    967  */
    968 
    969 /*
    970  * pmap_enter_pv: enter a mapping onto a vm_page lst
    971  *
    972  * => caller should hold the proper lock on pmap_main_lock
    973  * => caller should have pmap locked
    974  * => we will gain the lock on the vm_page and allocate the new pv_entry
    975  * => caller should adjust ptp's wire_count before calling
    976  * => caller should not adjust pmap's wire_count
    977  */
    978 static void
    979 pmap_enter_pv(struct vm_page_md *md, paddr_t pa, struct pv_entry *pv, pmap_t pm,
    980     vaddr_t va, u_int flags)
    981 {
    982 	struct pv_entry **pvp;
    983 
    984 	NPDEBUG(PDB_PVDUMP,
    985 	    printf("pmap_enter_pv: pm %p, md %p, flags 0x%x\n", pm, md, flags));
    986 
    987 	pv->pv_pmap = pm;
    988 	pv->pv_va = va;
    989 	pv->pv_flags = flags;
    990 
    991 	pvp = &SLIST_FIRST(&md->pvh_list);
    992 #ifdef PMAP_CACHE_VIPT
    993 	/*
    994 	 * Insert unmanaged entries, writeable first, at the head of
    995 	 * the pv list.
    996 	 */
    997 	if (__predict_true(!PV_IS_KENTRY_P(flags))) {
    998 		while (*pvp != NULL && PV_IS_KENTRY_P((*pvp)->pv_flags))
    999 			pvp = &SLIST_NEXT(*pvp, pv_link);
   1000 	}
   1001 	if (!PV_IS_WRITE_P(flags)) {
   1002 		while (*pvp != NULL && PV_IS_WRITE_P((*pvp)->pv_flags))
   1003 			pvp = &SLIST_NEXT(*pvp, pv_link);
   1004 	}
   1005 #endif
   1006 	SLIST_NEXT(pv, pv_link) = *pvp;		/* add to ... */
   1007 	*pvp = pv;				/* ... locked list */
   1008 	md->pvh_attrs |= flags & (PVF_REF | PVF_MOD);
   1009 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   1010 	if ((pv->pv_flags & PVF_KWRITE) == PVF_KWRITE)
   1011 		md->pvh_attrs |= PVF_KMOD;
   1012 	if ((md->pvh_attrs & (PVF_DMOD|PVF_NC)) != PVF_NC)
   1013 		md->pvh_attrs |= PVF_DIRTY;
   1014 	KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   1015 #endif
   1016 	if (pm == pmap_kernel()) {
   1017 		PMAPCOUNT(kernel_mappings);
   1018 		if (flags & PVF_WRITE)
   1019 			md->krw_mappings++;
   1020 		else
   1021 			md->kro_mappings++;
   1022 	} else {
   1023 		if (flags & PVF_WRITE)
   1024 			md->urw_mappings++;
   1025 		else
   1026 			md->uro_mappings++;
   1027 	}
   1028 
   1029 #ifdef PMAP_CACHE_VIPT
   1030 #ifndef ARM_MMU_EXTENDED
   1031 	/*
   1032 	 * Even though pmap_vac_me_harder will set PVF_WRITE for us,
   1033 	 * do it here as well to keep the mappings & KVF_WRITE consistent.
   1034 	 */
   1035 	if (arm_cache_prefer_mask != 0 && (flags & PVF_WRITE) != 0) {
   1036 		md->pvh_attrs |= PVF_WRITE;
   1037 	}
   1038 #endif
   1039 	/*
   1040 	 * If this is an exec mapping and its the first exec mapping
   1041 	 * for this page, make sure to sync the I-cache.
   1042 	 */
   1043 	if (PV_IS_EXEC_P(flags)) {
   1044 #ifndef ARM_MMU_EXTENDED
   1045 		if (!PV_IS_EXEC_P(md->pvh_attrs)) {
   1046 			pmap_syncicache_page(md, pa);
   1047 			PMAPCOUNT(exec_synced_map);
   1048 		}
   1049 #endif
   1050 		PMAPCOUNT(exec_mappings);
   1051 	}
   1052 #endif
   1053 
   1054 	PMAPCOUNT(mappings);
   1055 
   1056 	if (pv->pv_flags & PVF_WIRED)
   1057 		++pm->pm_stats.wired_count;
   1058 }
   1059 
   1060 /*
   1061  *
   1062  * pmap_find_pv: Find a pv entry
   1063  *
   1064  * => caller should hold lock on vm_page
   1065  */
   1066 static inline struct pv_entry *
   1067 pmap_find_pv(struct vm_page_md *md, pmap_t pm, vaddr_t va)
   1068 {
   1069 	struct pv_entry *pv;
   1070 
   1071 	SLIST_FOREACH(pv, &md->pvh_list, pv_link) {
   1072 		if (pm == pv->pv_pmap && va == pv->pv_va)
   1073 			break;
   1074 	}
   1075 
   1076 	return (pv);
   1077 }
   1078 
   1079 /*
   1080  * pmap_remove_pv: try to remove a mapping from a pv_list
   1081  *
   1082  * => caller should hold proper lock on pmap_main_lock
   1083  * => pmap should be locked
   1084  * => caller should hold lock on vm_page [so that attrs can be adjusted]
   1085  * => caller should adjust ptp's wire_count and free PTP if needed
   1086  * => caller should NOT adjust pmap's wire_count
   1087  * => we return the removed pv
   1088  */
   1089 static struct pv_entry *
   1090 pmap_remove_pv(struct vm_page_md *md, paddr_t pa, pmap_t pm, vaddr_t va)
   1091 {
   1092 	struct pv_entry *pv, **prevptr;
   1093 
   1094 	NPDEBUG(PDB_PVDUMP,
   1095 	    printf("pmap_remove_pv: pm %p, md %p, va 0x%08lx\n", pm, md, va));
   1096 
   1097 	prevptr = &SLIST_FIRST(&md->pvh_list); /* prev pv_entry ptr */
   1098 	pv = *prevptr;
   1099 
   1100 	while (pv) {
   1101 		if (pv->pv_pmap == pm && pv->pv_va == va) {	/* match? */
   1102 			NPDEBUG(PDB_PVDUMP, printf("pmap_remove_pv: pm %p, md "
   1103 			    "%p, flags 0x%x\n", pm, md, pv->pv_flags));
   1104 			if (pv->pv_flags & PVF_WIRED) {
   1105 				--pm->pm_stats.wired_count;
   1106 			}
   1107 			*prevptr = SLIST_NEXT(pv, pv_link);	/* remove it! */
   1108 			if (pm == pmap_kernel()) {
   1109 				PMAPCOUNT(kernel_unmappings);
   1110 				if (pv->pv_flags & PVF_WRITE)
   1111 					md->krw_mappings--;
   1112 				else
   1113 					md->kro_mappings--;
   1114 			} else {
   1115 				if (pv->pv_flags & PVF_WRITE)
   1116 					md->urw_mappings--;
   1117 				else
   1118 					md->uro_mappings--;
   1119 			}
   1120 
   1121 			PMAPCOUNT(unmappings);
   1122 #ifdef PMAP_CACHE_VIPT
   1123 			if (!(pv->pv_flags & PVF_WRITE))
   1124 				break;
   1125 			/*
   1126 			 * If this page has had an exec mapping, then if
   1127 			 * this was the last mapping, discard the contents,
   1128 			 * otherwise sync the i-cache for this page.
   1129 			 */
   1130 			if (PV_IS_EXEC_P(md->pvh_attrs)) {
   1131 #ifdef ARM_MMU_EXTENDED
   1132 				md->pvh_attrs &= ~PVF_EXEC;
   1133 				PMAPCOUNT(exec_discarded_unmap);
   1134 #else
   1135 				if (SLIST_EMPTY(&md->pvh_list)) {
   1136 					md->pvh_attrs &= ~PVF_EXEC;
   1137 					PMAPCOUNT(exec_discarded_unmap);
   1138 				} else {
   1139 					pmap_syncicache_page(md, pa);
   1140 					PMAPCOUNT(exec_synced_unmap);
   1141 				}
   1142 #endif /* ARM_MMU_EXTENDED */
   1143 			}
   1144 #endif /* PMAP_CACHE_VIPT */
   1145 			break;
   1146 		}
   1147 		prevptr = &SLIST_NEXT(pv, pv_link);	/* previous pointer */
   1148 		pv = *prevptr;				/* advance */
   1149 	}
   1150 
   1151 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   1152 	/*
   1153 	 * If we no longer have a WRITEABLE KENTRY at the head of list,
   1154 	 * clear the KMOD attribute from the page.
   1155 	 */
   1156 	if (SLIST_FIRST(&md->pvh_list) == NULL
   1157 	    || (SLIST_FIRST(&md->pvh_list)->pv_flags & PVF_KWRITE) != PVF_KWRITE)
   1158 		md->pvh_attrs &= ~PVF_KMOD;
   1159 
   1160 	/*
   1161 	 * If this was a writeable page and there are no more writeable
   1162 	 * mappings (ignoring KMPAGE), clear the WRITE flag and writeback
   1163 	 * the contents to memory.
   1164 	 */
   1165 	if (arm_cache_prefer_mask != 0) {
   1166 		if (md->krw_mappings + md->urw_mappings == 0)
   1167 			md->pvh_attrs &= ~PVF_WRITE;
   1168 		PMAP_VALIDATE_MD_PAGE(md);
   1169 	}
   1170 	KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   1171 #endif /* PMAP_CACHE_VIPT && !ARM_MMU_EXTENDED */
   1172 
   1173 	return(pv);				/* return removed pv */
   1174 }
   1175 
   1176 /*
   1177  *
   1178  * pmap_modify_pv: Update pv flags
   1179  *
   1180  * => caller should hold lock on vm_page [so that attrs can be adjusted]
   1181  * => caller should NOT adjust pmap's wire_count
   1182  * => caller must call pmap_vac_me_harder() if writable status of a page
   1183  *    may have changed.
   1184  * => we return the old flags
   1185  *
   1186  * Modify a physical-virtual mapping in the pv table
   1187  */
   1188 static u_int
   1189 pmap_modify_pv(struct vm_page_md *md, paddr_t pa, pmap_t pm, vaddr_t va,
   1190     u_int clr_mask, u_int set_mask)
   1191 {
   1192 	struct pv_entry *npv;
   1193 	u_int flags, oflags;
   1194 
   1195 	KASSERT(!PV_IS_KENTRY_P(clr_mask));
   1196 	KASSERT(!PV_IS_KENTRY_P(set_mask));
   1197 
   1198 	if ((npv = pmap_find_pv(md, pm, va)) == NULL)
   1199 		return (0);
   1200 
   1201 	NPDEBUG(PDB_PVDUMP,
   1202 	    printf("pmap_modify_pv: pm %p, md %p, clr 0x%x, set 0x%x, flags 0x%x\n", pm, md, clr_mask, set_mask, npv->pv_flags));
   1203 
   1204 	/*
   1205 	 * There is at least one VA mapping this page.
   1206 	 */
   1207 
   1208 	if (clr_mask & (PVF_REF | PVF_MOD)) {
   1209 		md->pvh_attrs |= set_mask & (PVF_REF | PVF_MOD);
   1210 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   1211 		if ((md->pvh_attrs & (PVF_DMOD|PVF_NC)) != PVF_NC)
   1212 			md->pvh_attrs |= PVF_DIRTY;
   1213 		KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   1214 #endif /* PMAP_CACHE_VIPT && !ARM_MMU_EXTENDED */
   1215 	}
   1216 
   1217 	oflags = npv->pv_flags;
   1218 	npv->pv_flags = flags = (oflags & ~clr_mask) | set_mask;
   1219 
   1220 	if ((flags ^ oflags) & PVF_WIRED) {
   1221 		if (flags & PVF_WIRED)
   1222 			++pm->pm_stats.wired_count;
   1223 		else
   1224 			--pm->pm_stats.wired_count;
   1225 	}
   1226 
   1227 	if ((flags ^ oflags) & PVF_WRITE) {
   1228 		if (pm == pmap_kernel()) {
   1229 			if (flags & PVF_WRITE) {
   1230 				md->krw_mappings++;
   1231 				md->kro_mappings--;
   1232 			} else {
   1233 				md->kro_mappings++;
   1234 				md->krw_mappings--;
   1235 			}
   1236 		} else {
   1237 			if (flags & PVF_WRITE) {
   1238 				md->urw_mappings++;
   1239 				md->uro_mappings--;
   1240 			} else {
   1241 				md->uro_mappings++;
   1242 				md->urw_mappings--;
   1243 			}
   1244 		}
   1245 	}
   1246 #ifdef PMAP_CACHE_VIPT
   1247 	if (arm_cache_prefer_mask != 0) {
   1248 		if (md->urw_mappings + md->krw_mappings == 0) {
   1249 			md->pvh_attrs &= ~PVF_WRITE;
   1250 		} else {
   1251 			md->pvh_attrs |= PVF_WRITE;
   1252 		}
   1253 	}
   1254 #ifndef ARM_MMU_EXTENDED
   1255 	/*
   1256 	 * We have two cases here: the first is from enter_pv (new exec
   1257 	 * page), the second is a combined pmap_remove_pv/pmap_enter_pv.
   1258 	 * Since in latter, pmap_enter_pv won't do anything, we just have
   1259 	 * to do what pmap_remove_pv would do.
   1260 	 */
   1261 	if ((PV_IS_EXEC_P(flags) && !PV_IS_EXEC_P(md->pvh_attrs))
   1262 	    || (PV_IS_EXEC_P(md->pvh_attrs)
   1263 		|| (!(flags & PVF_WRITE) && (oflags & PVF_WRITE)))) {
   1264 		pmap_syncicache_page(md, pa);
   1265 		PMAPCOUNT(exec_synced_remap);
   1266 	}
   1267 	KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   1268 #endif /* !ARM_MMU_EXTENDED */
   1269 #endif /* PMAP_CACHE_VIPT */
   1270 
   1271 	PMAPCOUNT(remappings);
   1272 
   1273 	return (oflags);
   1274 }
   1275 
   1276 /*
   1277  * Allocate an L1 translation table for the specified pmap.
   1278  * This is called at pmap creation time.
   1279  */
   1280 static void
   1281 pmap_alloc_l1(pmap_t pm)
   1282 {
   1283 #ifdef ARM_MMU_EXTENDED
   1284 #ifdef __HAVE_MM_MD_DIRECT_MAPPED_PHYS
   1285 	struct vm_page *pg;
   1286 	bool ok __diagused;
   1287 	for (;;) {
   1288 #ifdef PMAP_NEED_ALLOC_POOLPAGE
   1289 		pg = arm_pmap_alloc_poolpage(UVM_PGA_ZERO);
   1290 #else
   1291 		pg = uvm_pagealloc(NULL, 0, NULL, UVM_PGA_ZERO);
   1292 #endif
   1293 		if (pg != NULL)
   1294 			break;
   1295 		uvm_wait("pmapl1alloc");
   1296 	}
   1297 	pm->pm_l1_pa = VM_PAGE_TO_PHYS(pg);
   1298 	vaddr_t va = pmap_direct_mapped_phys(pm->pm_l1_pa, &ok, 0);
   1299 	KASSERT(ok);
   1300 	KASSERT(va >= KERNEL_BASE);
   1301 
   1302 #else
   1303 	KASSERTMSG(kernel_map != NULL, "pm %p", pm);
   1304 	vaddr_t va = uvm_km_alloc(kernel_map, PAGE_SIZE, 0,
   1305 	    UVM_KMF_WIRED|UVM_KMF_ZERO);
   1306 	KASSERT(va);
   1307 	pmap_extract(pmap_kernel(), va, &pm->pm_l1_pa);
   1308 #endif
   1309 	pm->pm_l1 = (pd_entry_t *)va;
   1310 	PTE_SYNC_RANGE(pm->pm_l1, PAGE_SIZE / sizeof(pt_entry_t));
   1311 #else
   1312 	struct l1_ttable *l1;
   1313 	uint8_t domain;
   1314 
   1315 	/*
   1316 	 * Remove the L1 at the head of the LRU list
   1317 	 */
   1318 	mutex_spin_enter(&l1_lru_lock);
   1319 	l1 = TAILQ_FIRST(&l1_lru_list);
   1320 	KDASSERT(l1 != NULL);
   1321 	TAILQ_REMOVE(&l1_lru_list, l1, l1_lru);
   1322 
   1323 	/*
   1324 	 * Pick the first available domain number, and update
   1325 	 * the link to the next number.
   1326 	 */
   1327 	domain = l1->l1_domain_first;
   1328 	l1->l1_domain_first = l1->l1_domain_free[domain];
   1329 
   1330 	/*
   1331 	 * If there are still free domain numbers in this L1,
   1332 	 * put it back on the TAIL of the LRU list.
   1333 	 */
   1334 	if (++l1->l1_domain_use_count < PMAP_DOMAINS)
   1335 		TAILQ_INSERT_TAIL(&l1_lru_list, l1, l1_lru);
   1336 
   1337 	mutex_spin_exit(&l1_lru_lock);
   1338 
   1339 	/*
   1340 	 * Fix up the relevant bits in the pmap structure
   1341 	 */
   1342 	pm->pm_l1 = l1;
   1343 	pm->pm_domain = domain + 1;
   1344 #endif
   1345 }
   1346 
   1347 /*
   1348  * Free an L1 translation table.
   1349  * This is called at pmap destruction time.
   1350  */
   1351 static void
   1352 pmap_free_l1(pmap_t pm)
   1353 {
   1354 #ifdef ARM_MMU_EXTENDED
   1355 #ifdef __HAVE_MM_MD_DIRECT_MAPPED_PHYS
   1356 	struct vm_page *pg = PHYS_TO_VM_PAGE(pm->pm_l1_pa);
   1357 	uvm_pagefree(pg);
   1358 #else
   1359 	uvm_km_free(kernel_map, (vaddr_t)pm->pm_l1, PAGE_SIZE, UVM_KMF_WIRED);
   1360 #endif
   1361 	pm->pm_l1 = NULL;
   1362 	pm->pm_l1_pa = 0;
   1363 #else
   1364 	struct l1_ttable *l1 = pm->pm_l1;
   1365 
   1366 	mutex_spin_enter(&l1_lru_lock);
   1367 
   1368 	/*
   1369 	 * If this L1 is currently on the LRU list, remove it.
   1370 	 */
   1371 	if (l1->l1_domain_use_count < PMAP_DOMAINS)
   1372 		TAILQ_REMOVE(&l1_lru_list, l1, l1_lru);
   1373 
   1374 	/*
   1375 	 * Free up the domain number which was allocated to the pmap
   1376 	 */
   1377 	l1->l1_domain_free[pmap_domain(pm) - 1] = l1->l1_domain_first;
   1378 	l1->l1_domain_first = pmap_domain(pm) - 1;
   1379 	l1->l1_domain_use_count--;
   1380 
   1381 	/*
   1382 	 * The L1 now must have at least 1 free domain, so add
   1383 	 * it back to the LRU list. If the use count is zero,
   1384 	 * put it at the head of the list, otherwise it goes
   1385 	 * to the tail.
   1386 	 */
   1387 	if (l1->l1_domain_use_count == 0)
   1388 		TAILQ_INSERT_HEAD(&l1_lru_list, l1, l1_lru);
   1389 	else
   1390 		TAILQ_INSERT_TAIL(&l1_lru_list, l1, l1_lru);
   1391 
   1392 	mutex_spin_exit(&l1_lru_lock);
   1393 #endif /* ARM_MMU_EXTENDED */
   1394 }
   1395 
   1396 #ifndef ARM_MMU_EXTENDED
   1397 static inline void
   1398 pmap_use_l1(pmap_t pm)
   1399 {
   1400 	struct l1_ttable *l1;
   1401 
   1402 	/*
   1403 	 * Do nothing if we're in interrupt context.
   1404 	 * Access to an L1 by the kernel pmap must not affect
   1405 	 * the LRU list.
   1406 	 */
   1407 	if (cpu_intr_p() || pm == pmap_kernel())
   1408 		return;
   1409 
   1410 	l1 = pm->pm_l1;
   1411 
   1412 	/*
   1413 	 * If the L1 is not currently on the LRU list, just return
   1414 	 */
   1415 	if (l1->l1_domain_use_count == PMAP_DOMAINS)
   1416 		return;
   1417 
   1418 	mutex_spin_enter(&l1_lru_lock);
   1419 
   1420 	/*
   1421 	 * Check the use count again, now that we've acquired the lock
   1422 	 */
   1423 	if (l1->l1_domain_use_count == PMAP_DOMAINS) {
   1424 		mutex_spin_exit(&l1_lru_lock);
   1425 		return;
   1426 	}
   1427 
   1428 	/*
   1429 	 * Move the L1 to the back of the LRU list
   1430 	 */
   1431 	TAILQ_REMOVE(&l1_lru_list, l1, l1_lru);
   1432 	TAILQ_INSERT_TAIL(&l1_lru_list, l1, l1_lru);
   1433 
   1434 	mutex_spin_exit(&l1_lru_lock);
   1435 }
   1436 #endif /* !ARM_MMU_EXTENDED */
   1437 
   1438 /*
   1439  * void pmap_free_l2_ptp(pt_entry_t *, paddr_t *)
   1440  *
   1441  * Free an L2 descriptor table.
   1442  */
   1443 static inline void
   1444 #if defined(PMAP_INCLUDE_PTE_SYNC) && defined(PMAP_CACHE_VIVT)
   1445 pmap_free_l2_ptp(bool need_sync, pt_entry_t *l2, paddr_t pa)
   1446 #else
   1447 pmap_free_l2_ptp(pt_entry_t *l2, paddr_t pa)
   1448 #endif
   1449 {
   1450 #if defined(PMAP_INCLUDE_PTE_SYNC) && defined(PMAP_CACHE_VIVT)
   1451 	/*
   1452 	 * Note: With a write-back cache, we may need to sync this
   1453 	 * L2 table before re-using it.
   1454 	 * This is because it may have belonged to a non-current
   1455 	 * pmap, in which case the cache syncs would have been
   1456 	 * skipped for the pages that were being unmapped. If the
   1457 	 * L2 table were then to be immediately re-allocated to
   1458 	 * the *current* pmap, it may well contain stale mappings
   1459 	 * which have not yet been cleared by a cache write-back
   1460 	 * and so would still be visible to the mmu.
   1461 	 */
   1462 	if (need_sync)
   1463 		PTE_SYNC_RANGE(l2, L2_TABLE_SIZE_REAL / sizeof(pt_entry_t));
   1464 #endif /* PMAP_INCLUDE_PTE_SYNC && PMAP_CACHE_VIVT */
   1465 	pool_cache_put_paddr(&pmap_l2ptp_cache, (void *)l2, pa);
   1466 }
   1467 
   1468 /*
   1469  * Returns a pointer to the L2 bucket associated with the specified pmap
   1470  * and VA, or NULL if no L2 bucket exists for the address.
   1471  */
   1472 static inline struct l2_bucket *
   1473 pmap_get_l2_bucket(pmap_t pm, vaddr_t va)
   1474 {
   1475 	const size_t l1slot = l1pte_index(va);
   1476 	struct l2_dtable *l2;
   1477 	struct l2_bucket *l2b;
   1478 
   1479 	if ((l2 = pm->pm_l2[L2_IDX(l1slot)]) == NULL ||
   1480 	    (l2b = &l2->l2_bucket[L2_BUCKET(l1slot)])->l2b_kva == NULL)
   1481 		return (NULL);
   1482 
   1483 	return (l2b);
   1484 }
   1485 
   1486 /*
   1487  * Returns a pointer to the L2 bucket associated with the specified pmap
   1488  * and VA.
   1489  *
   1490  * If no L2 bucket exists, perform the necessary allocations to put an L2
   1491  * bucket/page table in place.
   1492  *
   1493  * Note that if a new L2 bucket/page was allocated, the caller *must*
   1494  * increment the bucket occupancy counter appropriately *before*
   1495  * releasing the pmap's lock to ensure no other thread or cpu deallocates
   1496  * the bucket/page in the meantime.
   1497  */
   1498 static struct l2_bucket *
   1499 pmap_alloc_l2_bucket(pmap_t pm, vaddr_t va)
   1500 {
   1501 	const size_t l1slot = l1pte_index(va);
   1502 	struct l2_dtable *l2;
   1503 
   1504 	if ((l2 = pm->pm_l2[L2_IDX(l1slot)]) == NULL) {
   1505 		/*
   1506 		 * No mapping at this address, as there is
   1507 		 * no entry in the L1 table.
   1508 		 * Need to allocate a new l2_dtable.
   1509 		 */
   1510 		if ((l2 = pmap_alloc_l2_dtable()) == NULL)
   1511 			return (NULL);
   1512 
   1513 		/*
   1514 		 * Link it into the parent pmap
   1515 		 */
   1516 		pm->pm_l2[L2_IDX(l1slot)] = l2;
   1517 	}
   1518 
   1519 	struct l2_bucket * const l2b = &l2->l2_bucket[L2_BUCKET(l1slot)];
   1520 
   1521 	/*
   1522 	 * Fetch pointer to the L2 page table associated with the address.
   1523 	 */
   1524 	if (l2b->l2b_kva == NULL) {
   1525 		pt_entry_t *ptep;
   1526 
   1527 		/*
   1528 		 * No L2 page table has been allocated. Chances are, this
   1529 		 * is because we just allocated the l2_dtable, above.
   1530 		 */
   1531 		if ((ptep = pmap_alloc_l2_ptp(&l2b->l2b_pa)) == NULL) {
   1532 			/*
   1533 			 * Oops, no more L2 page tables available at this
   1534 			 * time. We may need to deallocate the l2_dtable
   1535 			 * if we allocated a new one above.
   1536 			 */
   1537 			if (l2->l2_occupancy == 0) {
   1538 				pm->pm_l2[L2_IDX(l1slot)] = NULL;
   1539 				pmap_free_l2_dtable(l2);
   1540 			}
   1541 			return (NULL);
   1542 		}
   1543 
   1544 		l2->l2_occupancy++;
   1545 		l2b->l2b_kva = ptep;
   1546 		l2b->l2b_l1slot = l1slot;
   1547 
   1548 #ifdef ARM_MMU_EXTENDED
   1549 		/*
   1550 		 * We know there will be a mapping here, so simply
   1551 		 * enter this PTP into the L1 now.
   1552 		 */
   1553 		pd_entry_t * const pdep = pmap_l1_kva(pm) + l1slot;
   1554 		pd_entry_t npde = L1_C_PROTO | l2b->l2b_pa
   1555 		    | L1_C_DOM(pmap_domain(pm));
   1556 		KASSERT(*pdep == 0);
   1557 		l1pte_setone(pdep, npde);
   1558 		PTE_SYNC(pdep);
   1559 #endif
   1560 	}
   1561 
   1562 	return (l2b);
   1563 }
   1564 
   1565 /*
   1566  * One or more mappings in the specified L2 descriptor table have just been
   1567  * invalidated.
   1568  *
   1569  * Garbage collect the metadata and descriptor table itself if necessary.
   1570  *
   1571  * The pmap lock must be acquired when this is called (not necessary
   1572  * for the kernel pmap).
   1573  */
   1574 static void
   1575 pmap_free_l2_bucket(pmap_t pm, struct l2_bucket *l2b, u_int count)
   1576 {
   1577 	KDASSERT(count <= l2b->l2b_occupancy);
   1578 
   1579 	/*
   1580 	 * Update the bucket's reference count according to how many
   1581 	 * PTEs the caller has just invalidated.
   1582 	 */
   1583 	l2b->l2b_occupancy -= count;
   1584 
   1585 	/*
   1586 	 * Note:
   1587 	 *
   1588 	 * Level 2 page tables allocated to the kernel pmap are never freed
   1589 	 * as that would require checking all Level 1 page tables and
   1590 	 * removing any references to the Level 2 page table. See also the
   1591 	 * comment elsewhere about never freeing bootstrap L2 descriptors.
   1592 	 *
   1593 	 * We make do with just invalidating the mapping in the L2 table.
   1594 	 *
   1595 	 * This isn't really a big deal in practice and, in fact, leads
   1596 	 * to a performance win over time as we don't need to continually
   1597 	 * alloc/free.
   1598 	 */
   1599 	if (l2b->l2b_occupancy > 0 || pm == pmap_kernel())
   1600 		return;
   1601 
   1602 	/*
   1603 	 * There are no more valid mappings in this level 2 page table.
   1604 	 * Go ahead and NULL-out the pointer in the bucket, then
   1605 	 * free the page table.
   1606 	 */
   1607 	const size_t l1slot = l2b->l2b_l1slot;
   1608 	pt_entry_t * const ptep = l2b->l2b_kva;
   1609 	l2b->l2b_kva = NULL;
   1610 
   1611 	pd_entry_t * const pdep = pmap_l1_kva(pm) + l1slot;
   1612 	pd_entry_t pde __diagused = *pdep;
   1613 
   1614 #ifdef ARM_MMU_EXTENDED
   1615 	/*
   1616 	 * Invalidate the L1 slot.
   1617 	 */
   1618 	KASSERT((pde & L1_TYPE_MASK) == L1_TYPE_C);
   1619 #else
   1620 	/*
   1621 	 * If the L1 slot matches the pmap's domain number, then invalidate it.
   1622 	 */
   1623 	if ((pde & (L1_C_DOM_MASK|L1_TYPE_MASK))
   1624 	    == (L1_C_DOM(pmap_domain(pm))|L1_TYPE_C)) {
   1625 #endif
   1626 		l1pte_setone(pdep, 0);
   1627 		PDE_SYNC(pdep);
   1628 #ifndef ARM_MMU_EXTENDED
   1629 	}
   1630 #endif
   1631 
   1632 	/*
   1633 	 * Release the L2 descriptor table back to the pool cache.
   1634 	 */
   1635 #if defined(PMAP_INCLUDE_PTE_SYNC) && defined(PMAP_CACHE_VIVT)
   1636 	pmap_free_l2_ptp(!pmap_is_cached(pm), ptep, l2b->l2b_pa);
   1637 #else
   1638 	pmap_free_l2_ptp(ptep, l2b->l2b_pa);
   1639 #endif
   1640 
   1641 	/*
   1642 	 * Update the reference count in the associated l2_dtable
   1643 	 */
   1644 	struct l2_dtable * const l2 = pm->pm_l2[L2_IDX(l1slot)];
   1645 	if (--l2->l2_occupancy > 0)
   1646 		return;
   1647 
   1648 	/*
   1649 	 * There are no more valid mappings in any of the Level 1
   1650 	 * slots managed by this l2_dtable. Go ahead and NULL-out
   1651 	 * the pointer in the parent pmap and free the l2_dtable.
   1652 	 */
   1653 	pm->pm_l2[L2_IDX(l1slot)] = NULL;
   1654 	pmap_free_l2_dtable(l2);
   1655 }
   1656 
   1657 /*
   1658  * Pool cache constructors for L2 descriptor tables, metadata and pmap
   1659  * structures.
   1660  */
   1661 static int
   1662 pmap_l2ptp_ctor(void *arg, void *v, int flags)
   1663 {
   1664 #ifndef PMAP_INCLUDE_PTE_SYNC
   1665 	vaddr_t va = (vaddr_t)v & ~PGOFSET;
   1666 
   1667 	/*
   1668 	 * The mappings for these page tables were initially made using
   1669 	 * pmap_kenter_pa() by the pool subsystem. Therefore, the cache-
   1670 	 * mode will not be right for page table mappings. To avoid
   1671 	 * polluting the pmap_kenter_pa() code with a special case for
   1672 	 * page tables, we simply fix up the cache-mode here if it's not
   1673 	 * correct.
   1674 	 */
   1675 	if (pte_l2_s_cache_mode != pte_l2_s_cache_mode_pt) {
   1676 		const struct l2_bucket * const l2b =
   1677 		    pmap_get_l2_bucket(pmap_kernel(), va);
   1678 		KASSERTMSG(l2b != NULL, "%#lx", va);
   1679 		pt_entry_t * const ptep = &l2b->l2b_kva[l2pte_index(va)];
   1680 		const pt_entry_t opte = *ptep;
   1681 
   1682 		if ((opte & L2_S_CACHE_MASK) != pte_l2_s_cache_mode_pt) {
   1683 			/*
   1684 			 * Page tables must have the cache-mode set correctly.
   1685 			 */
   1686 			const pt_entry_t npte = (pte & ~L2_S_CACHE_MASK)
   1687 			    | pte_l2_s_cache_mode_pt;
   1688 			l2pte_set(ptep, npte, opte);
   1689 			PTE_SYNC(ptep);
   1690 			cpu_tlb_flushD_SE(va);
   1691 			cpu_cpwait();
   1692 		}
   1693 	}
   1694 #endif
   1695 
   1696 	memset(v, 0, L2_TABLE_SIZE_REAL);
   1697 	PTE_SYNC_RANGE(v, L2_TABLE_SIZE_REAL / sizeof(pt_entry_t));
   1698 	return (0);
   1699 }
   1700 
   1701 static int
   1702 pmap_l2dtable_ctor(void *arg, void *v, int flags)
   1703 {
   1704 
   1705 	memset(v, 0, sizeof(struct l2_dtable));
   1706 	return (0);
   1707 }
   1708 
   1709 static int
   1710 pmap_pmap_ctor(void *arg, void *v, int flags)
   1711 {
   1712 
   1713 	memset(v, 0, sizeof(struct pmap));
   1714 	return (0);
   1715 }
   1716 
   1717 static void
   1718 pmap_pinit(pmap_t pm)
   1719 {
   1720 #ifndef ARM_HAS_VBAR
   1721 	struct l2_bucket *l2b;
   1722 
   1723 	if (vector_page < KERNEL_BASE) {
   1724 		/*
   1725 		 * Map the vector page.
   1726 		 */
   1727 		pmap_enter(pm, vector_page, systempage.pv_pa,
   1728 		    VM_PROT_READ | VM_PROT_EXECUTE,
   1729 		    VM_PROT_READ | VM_PROT_EXECUTE | PMAP_WIRED);
   1730 		pmap_update(pm);
   1731 
   1732 		pm->pm_pl1vec = pmap_l1_kva(pm) + l1pte_index(vector_page);
   1733 		l2b = pmap_get_l2_bucket(pm, vector_page);
   1734 		KASSERTMSG(l2b != NULL, "%#lx", vector_page);
   1735 		pm->pm_l1vec = l2b->l2b_pa | L1_C_PROTO |
   1736 		    L1_C_DOM(pmap_domain(pm));
   1737 	} else
   1738 		pm->pm_pl1vec = NULL;
   1739 #endif
   1740 }
   1741 
   1742 #ifdef PMAP_CACHE_VIVT
   1743 /*
   1744  * Since we have a virtually indexed cache, we may need to inhibit caching if
   1745  * there is more than one mapping and at least one of them is writable.
   1746  * Since we purge the cache on every context switch, we only need to check for
   1747  * other mappings within the same pmap, or kernel_pmap.
   1748  * This function is also called when a page is unmapped, to possibly reenable
   1749  * caching on any remaining mappings.
   1750  *
   1751  * The code implements the following logic, where:
   1752  *
   1753  * KW = # of kernel read/write pages
   1754  * KR = # of kernel read only pages
   1755  * UW = # of user read/write pages
   1756  * UR = # of user read only pages
   1757  *
   1758  * KC = kernel mapping is cacheable
   1759  * UC = user mapping is cacheable
   1760  *
   1761  *               KW=0,KR=0  KW=0,KR>0  KW=1,KR=0  KW>1,KR>=0
   1762  *             +---------------------------------------------
   1763  * UW=0,UR=0   | ---        KC=1       KC=1       KC=0
   1764  * UW=0,UR>0   | UC=1       KC=1,UC=1  KC=0,UC=0  KC=0,UC=0
   1765  * UW=1,UR=0   | UC=1       KC=0,UC=0  KC=0,UC=0  KC=0,UC=0
   1766  * UW>1,UR>=0  | UC=0       KC=0,UC=0  KC=0,UC=0  KC=0,UC=0
   1767  */
   1768 
   1769 static const int pmap_vac_flags[4][4] = {
   1770 	{-1,		0,		0,		PVF_KNC},
   1771 	{0,		0,		PVF_NC,		PVF_NC},
   1772 	{0,		PVF_NC,		PVF_NC,		PVF_NC},
   1773 	{PVF_UNC,	PVF_NC,		PVF_NC,		PVF_NC}
   1774 };
   1775 
   1776 static inline int
   1777 pmap_get_vac_flags(const struct vm_page_md *md)
   1778 {
   1779 	int kidx, uidx;
   1780 
   1781 	kidx = 0;
   1782 	if (md->kro_mappings || md->krw_mappings > 1)
   1783 		kidx |= 1;
   1784 	if (md->krw_mappings)
   1785 		kidx |= 2;
   1786 
   1787 	uidx = 0;
   1788 	if (md->uro_mappings || md->urw_mappings > 1)
   1789 		uidx |= 1;
   1790 	if (md->urw_mappings)
   1791 		uidx |= 2;
   1792 
   1793 	return (pmap_vac_flags[uidx][kidx]);
   1794 }
   1795 
   1796 static inline void
   1797 pmap_vac_me_harder(struct vm_page_md *md, paddr_t pa, pmap_t pm, vaddr_t va)
   1798 {
   1799 	int nattr;
   1800 
   1801 	nattr = pmap_get_vac_flags(md);
   1802 
   1803 	if (nattr < 0) {
   1804 		md->pvh_attrs &= ~PVF_NC;
   1805 		return;
   1806 	}
   1807 
   1808 	if (nattr == 0 && (md->pvh_attrs & PVF_NC) == 0)
   1809 		return;
   1810 
   1811 	if (pm == pmap_kernel())
   1812 		pmap_vac_me_kpmap(md, pa, pm, va);
   1813 	else
   1814 		pmap_vac_me_user(md, pa, pm, va);
   1815 
   1816 	md->pvh_attrs = (md->pvh_attrs & ~PVF_NC) | nattr;
   1817 }
   1818 
   1819 static void
   1820 pmap_vac_me_kpmap(struct vm_page_md *md, paddr_t pa, pmap_t pm, vaddr_t va)
   1821 {
   1822 	u_int u_cacheable, u_entries;
   1823 	struct pv_entry *pv;
   1824 	pmap_t last_pmap = pm;
   1825 
   1826 	/*
   1827 	 * Pass one, see if there are both kernel and user pmaps for
   1828 	 * this page.  Calculate whether there are user-writable or
   1829 	 * kernel-writable pages.
   1830 	 */
   1831 	u_cacheable = 0;
   1832 	SLIST_FOREACH(pv, &md->pvh_list, pv_link) {
   1833 		if (pv->pv_pmap != pm && (pv->pv_flags & PVF_NC) == 0)
   1834 			u_cacheable++;
   1835 	}
   1836 
   1837 	u_entries = md->urw_mappings + md->uro_mappings;
   1838 
   1839 	/*
   1840 	 * We know we have just been updating a kernel entry, so if
   1841 	 * all user pages are already cacheable, then there is nothing
   1842 	 * further to do.
   1843 	 */
   1844 	if (md->k_mappings == 0 && u_cacheable == u_entries)
   1845 		return;
   1846 
   1847 	if (u_entries) {
   1848 		/*
   1849 		 * Scan over the list again, for each entry, if it
   1850 		 * might not be set correctly, call pmap_vac_me_user
   1851 		 * to recalculate the settings.
   1852 		 */
   1853 		SLIST_FOREACH(pv, &md->pvh_list, pv_link) {
   1854 			/*
   1855 			 * We know kernel mappings will get set
   1856 			 * correctly in other calls.  We also know
   1857 			 * that if the pmap is the same as last_pmap
   1858 			 * then we've just handled this entry.
   1859 			 */
   1860 			if (pv->pv_pmap == pm || pv->pv_pmap == last_pmap)
   1861 				continue;
   1862 
   1863 			/*
   1864 			 * If there are kernel entries and this page
   1865 			 * is writable but non-cacheable, then we can
   1866 			 * skip this entry also.
   1867 			 */
   1868 			if (md->k_mappings &&
   1869 			    (pv->pv_flags & (PVF_NC | PVF_WRITE)) ==
   1870 			    (PVF_NC | PVF_WRITE))
   1871 				continue;
   1872 
   1873 			/*
   1874 			 * Similarly if there are no kernel-writable
   1875 			 * entries and the page is already
   1876 			 * read-only/cacheable.
   1877 			 */
   1878 			if (md->krw_mappings == 0 &&
   1879 			    (pv->pv_flags & (PVF_NC | PVF_WRITE)) == 0)
   1880 				continue;
   1881 
   1882 			/*
   1883 			 * For some of the remaining cases, we know
   1884 			 * that we must recalculate, but for others we
   1885 			 * can't tell if they are correct or not, so
   1886 			 * we recalculate anyway.
   1887 			 */
   1888 			pmap_vac_me_user(md, pa, (last_pmap = pv->pv_pmap), 0);
   1889 		}
   1890 
   1891 		if (md->k_mappings == 0)
   1892 			return;
   1893 	}
   1894 
   1895 	pmap_vac_me_user(md, pa, pm, va);
   1896 }
   1897 
   1898 static void
   1899 pmap_vac_me_user(struct vm_page_md *md, paddr_t pa, pmap_t pm, vaddr_t va)
   1900 {
   1901 	pmap_t kpmap = pmap_kernel();
   1902 	struct pv_entry *pv, *npv = NULL;
   1903 	u_int entries = 0;
   1904 	u_int writable = 0;
   1905 	u_int cacheable_entries = 0;
   1906 	u_int kern_cacheable = 0;
   1907 	u_int other_writable = 0;
   1908 
   1909 	/*
   1910 	 * Count mappings and writable mappings in this pmap.
   1911 	 * Include kernel mappings as part of our own.
   1912 	 * Keep a pointer to the first one.
   1913 	 */
   1914 	npv = NULL;
   1915 	KASSERT(pmap_page_locked_p(md));
   1916 	SLIST_FOREACH(pv, &md->pvh_list, pv_link) {
   1917 		/* Count mappings in the same pmap */
   1918 		if (pm == pv->pv_pmap || kpmap == pv->pv_pmap) {
   1919 			if (entries++ == 0)
   1920 				npv = pv;
   1921 
   1922 			/* Cacheable mappings */
   1923 			if ((pv->pv_flags & PVF_NC) == 0) {
   1924 				cacheable_entries++;
   1925 				if (kpmap == pv->pv_pmap)
   1926 					kern_cacheable++;
   1927 			}
   1928 
   1929 			/* Writable mappings */
   1930 			if (pv->pv_flags & PVF_WRITE)
   1931 				++writable;
   1932 		} else
   1933 		if (pv->pv_flags & PVF_WRITE)
   1934 			other_writable = 1;
   1935 	}
   1936 
   1937 	/*
   1938 	 * Enable or disable caching as necessary.
   1939 	 * Note: the first entry might be part of the kernel pmap,
   1940 	 * so we can't assume this is indicative of the state of the
   1941 	 * other (maybe non-kpmap) entries.
   1942 	 */
   1943 	if ((entries > 1 && writable) ||
   1944 	    (entries > 0 && pm == kpmap && other_writable)) {
   1945 		if (cacheable_entries == 0) {
   1946 			return;
   1947 		}
   1948 
   1949 		for (pv = npv; pv; pv = SLIST_NEXT(pv, pv_link)) {
   1950 			if ((pm != pv->pv_pmap && kpmap != pv->pv_pmap) ||
   1951 			    (pv->pv_flags & PVF_NC))
   1952 				continue;
   1953 
   1954 			pv->pv_flags |= PVF_NC;
   1955 
   1956 			struct l2_bucket * const l2b
   1957 			    = pmap_get_l2_bucket(pv->pv_pmap, pv->pv_va);
   1958 			KASSERTMSG(l2b != NULL, "%#lx", va);
   1959 			pt_entry_t * const ptep
   1960 			    = &l2b->l2b_kva[l2pte_index(pv->pv_va)];
   1961 			const pt_entry_t opte = *ptep;
   1962 			pt_entry_t npte = opte & ~L2_S_CACHE_MASK;
   1963 
   1964 			if ((va != pv->pv_va || pm != pv->pv_pmap)
   1965 			    && l2pte_valid_p(npte)) {
   1966 #ifdef PMAP_CACHE_VIVT
   1967 				pmap_cache_wbinv_page(pv->pv_pmap, pv->pv_va,
   1968 				    true, pv->pv_flags);
   1969 #endif
   1970 				pmap_tlb_flush_SE(pv->pv_pmap, pv->pv_va,
   1971 				    pv->pv_flags);
   1972 			}
   1973 
   1974 			l2pte_set(ptep, npte, opte);
   1975 			PTE_SYNC_CURRENT(pv->pv_pmap, ptep);
   1976 		}
   1977 		cpu_cpwait();
   1978 	} else
   1979 	if (entries > cacheable_entries) {
   1980 		/*
   1981 		 * Turn cacheing back on for some pages.  If it is a kernel
   1982 		 * page, only do so if there are no other writable pages.
   1983 		 */
   1984 		for (pv = npv; pv; pv = SLIST_NEXT(pv, pv_link)) {
   1985 			if (!(pv->pv_flags & PVF_NC) || (pm != pv->pv_pmap &&
   1986 			    (kpmap != pv->pv_pmap || other_writable)))
   1987 				continue;
   1988 
   1989 			pv->pv_flags &= ~PVF_NC;
   1990 
   1991 			struct l2_bucket * const l2b
   1992 			    = pmap_get_l2_bucket(pv->pv_pmap, pv->pv_va);
   1993 			KASSERTMSG(l2b != NULL, "%#lx", va);
   1994 			pt_entry_t * const ptep
   1995 			    = &l2b->l2b_kva[l2pte_index(pv->pv_va)];
   1996 			const pt_entry_t opte = *ptep;
   1997 			pt_entry_t npte = (opte & ~L2_S_CACHE_MASK)
   1998 			    | pte_l2_s_cache_mode;
   1999 
   2000 			if (l2pte_valid_p(opte)) {
   2001 				pmap_tlb_flush_SE(pv->pv_pmap, pv->pv_va,
   2002 				    pv->pv_flags);
   2003 			}
   2004 
   2005 			l2pte_set(ptep, npte, opte);
   2006 			PTE_SYNC_CURRENT(pv->pv_pmap, ptep);
   2007 		}
   2008 	}
   2009 }
   2010 #endif
   2011 
   2012 #ifdef PMAP_CACHE_VIPT
   2013 static void
   2014 pmap_vac_me_harder(struct vm_page_md *md, paddr_t pa, pmap_t pm, vaddr_t va)
   2015 {
   2016 #ifndef ARM_MMU_EXTENDED
   2017 	struct pv_entry *pv;
   2018 	vaddr_t tst_mask;
   2019 	bool bad_alias;
   2020 	const u_int
   2021 	    rw_mappings = md->urw_mappings + md->krw_mappings,
   2022 	    ro_mappings = md->uro_mappings + md->kro_mappings;
   2023 
   2024 	/* do we need to do anything? */
   2025 	if (arm_cache_prefer_mask == 0)
   2026 		return;
   2027 
   2028 	NPDEBUG(PDB_VAC, printf("pmap_vac_me_harder: md=%p, pmap=%p va=%08lx\n",
   2029 	    md, pm, va));
   2030 
   2031 	KASSERT(!va || pm);
   2032 	KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   2033 
   2034 	/* Already a conflict? */
   2035 	if (__predict_false(md->pvh_attrs & PVF_NC)) {
   2036 		/* just an add, things are already non-cached */
   2037 		KASSERT(!(md->pvh_attrs & PVF_DIRTY));
   2038 		KASSERT(!(md->pvh_attrs & PVF_MULTCLR));
   2039 		bad_alias = false;
   2040 		if (va) {
   2041 			PMAPCOUNT(vac_color_none);
   2042 			bad_alias = true;
   2043 			KASSERT((rw_mappings == 0) == !(md->pvh_attrs & PVF_WRITE));
   2044 			goto fixup;
   2045 		}
   2046 		pv = SLIST_FIRST(&md->pvh_list);
   2047 		/* the list can't be empty because it would be cachable */
   2048 		if (md->pvh_attrs & PVF_KMPAGE) {
   2049 			tst_mask = md->pvh_attrs;
   2050 		} else {
   2051 			KASSERT(pv);
   2052 			tst_mask = pv->pv_va;
   2053 			pv = SLIST_NEXT(pv, pv_link);
   2054 		}
   2055 		/*
   2056 		 * Only check for a bad alias if we have writable mappings.
   2057 		 */
   2058 		tst_mask &= arm_cache_prefer_mask;
   2059 		if (rw_mappings > 0) {
   2060 			for (; pv && !bad_alias; pv = SLIST_NEXT(pv, pv_link)) {
   2061 				/* if there's a bad alias, stop checking. */
   2062 				if (tst_mask != (pv->pv_va & arm_cache_prefer_mask))
   2063 					bad_alias = true;
   2064 			}
   2065 			md->pvh_attrs |= PVF_WRITE;
   2066 			if (!bad_alias)
   2067 				md->pvh_attrs |= PVF_DIRTY;
   2068 		} else {
   2069 			/*
   2070 			 * We have only read-only mappings.  Let's see if there
   2071 			 * are multiple colors in use or if we mapped a KMPAGE.
   2072 			 * If the latter, we have a bad alias.  If the former,
   2073 			 * we need to remember that.
   2074 			 */
   2075 			for (; pv; pv = SLIST_NEXT(pv, pv_link)) {
   2076 				if (tst_mask != (pv->pv_va & arm_cache_prefer_mask)) {
   2077 					if (md->pvh_attrs & PVF_KMPAGE)
   2078 						bad_alias = true;
   2079 					break;
   2080 				}
   2081 			}
   2082 			md->pvh_attrs &= ~PVF_WRITE;
   2083 			/*
   2084 			 * No KMPAGE and we exited early, so we must have
   2085 			 * multiple color mappings.
   2086 			 */
   2087 			if (!bad_alias && pv != NULL)
   2088 				md->pvh_attrs |= PVF_MULTCLR;
   2089 		}
   2090 
   2091 		/* If no conflicting colors, set everything back to cached */
   2092 		if (!bad_alias) {
   2093 #ifdef DEBUG
   2094 			if ((md->pvh_attrs & PVF_WRITE)
   2095 			    || ro_mappings < 2) {
   2096 				SLIST_FOREACH(pv, &md->pvh_list, pv_link)
   2097 					KDASSERT(((tst_mask ^ pv->pv_va) & arm_cache_prefer_mask) == 0);
   2098 			}
   2099 #endif
   2100 			md->pvh_attrs &= (PAGE_SIZE - 1) & ~PVF_NC;
   2101 			md->pvh_attrs |= tst_mask | PVF_COLORED;
   2102 			/*
   2103 			 * Restore DIRTY bit if page is modified
   2104 			 */
   2105 			if (md->pvh_attrs & PVF_DMOD)
   2106 				md->pvh_attrs |= PVF_DIRTY;
   2107 			PMAPCOUNT(vac_color_restore);
   2108 		} else {
   2109 			KASSERT(SLIST_FIRST(&md->pvh_list) != NULL);
   2110 			KASSERT(SLIST_NEXT(SLIST_FIRST(&md->pvh_list), pv_link) != NULL);
   2111 		}
   2112 		KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   2113 		KASSERT((rw_mappings == 0) == !(md->pvh_attrs & PVF_WRITE));
   2114 	} else if (!va) {
   2115 		KASSERT(pmap_is_page_colored_p(md));
   2116 		KASSERT(!(md->pvh_attrs & PVF_WRITE)
   2117 		    || (md->pvh_attrs & PVF_DIRTY));
   2118 		if (rw_mappings == 0) {
   2119 			md->pvh_attrs &= ~PVF_WRITE;
   2120 			if (ro_mappings == 1
   2121 			    && (md->pvh_attrs & PVF_MULTCLR)) {
   2122 				/*
   2123 				 * If this is the last readonly mapping
   2124 				 * but it doesn't match the current color
   2125 				 * for the page, change the current color
   2126 				 * to match this last readonly mapping.
   2127 				 */
   2128 				pv = SLIST_FIRST(&md->pvh_list);
   2129 				tst_mask = (md->pvh_attrs ^ pv->pv_va)
   2130 				    & arm_cache_prefer_mask;
   2131 				if (tst_mask) {
   2132 					md->pvh_attrs ^= tst_mask;
   2133 					PMAPCOUNT(vac_color_change);
   2134 				}
   2135 			}
   2136 		}
   2137 		KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   2138 		KASSERT((rw_mappings == 0) == !(md->pvh_attrs & PVF_WRITE));
   2139 		return;
   2140 	} else if (!pmap_is_page_colored_p(md)) {
   2141 		/* not colored so we just use its color */
   2142 		KASSERT(md->pvh_attrs & (PVF_WRITE|PVF_DIRTY));
   2143 		KASSERT(!(md->pvh_attrs & PVF_MULTCLR));
   2144 		PMAPCOUNT(vac_color_new);
   2145 		md->pvh_attrs &= PAGE_SIZE - 1;
   2146 		md->pvh_attrs |= PVF_COLORED
   2147 		    | (va & arm_cache_prefer_mask)
   2148 		    | (rw_mappings > 0 ? PVF_WRITE : 0);
   2149 		KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   2150 		KASSERT((rw_mappings == 0) == !(md->pvh_attrs & PVF_WRITE));
   2151 		return;
   2152 	} else if (((md->pvh_attrs ^ va) & arm_cache_prefer_mask) == 0) {
   2153 		bad_alias = false;
   2154 		if (rw_mappings > 0) {
   2155 			/*
   2156 			 * We now have writeable mappings and if we have
   2157 			 * readonly mappings in more than once color, we have
   2158 			 * an aliasing problem.  Regardless mark the page as
   2159 			 * writeable.
   2160 			 */
   2161 			if (md->pvh_attrs & PVF_MULTCLR) {
   2162 				if (ro_mappings < 2) {
   2163 					/*
   2164 					 * If we only have less than two
   2165 					 * read-only mappings, just flush the
   2166 					 * non-primary colors from the cache.
   2167 					 */
   2168 					pmap_flush_page(md, pa,
   2169 					    PMAP_FLUSH_SECONDARY);
   2170 				} else {
   2171 					bad_alias = true;
   2172 				}
   2173 			}
   2174 			md->pvh_attrs |= PVF_WRITE;
   2175 		}
   2176 		/* If no conflicting colors, set everything back to cached */
   2177 		if (!bad_alias) {
   2178 #ifdef DEBUG
   2179 			if (rw_mappings > 0
   2180 			    || (md->pvh_attrs & PMAP_KMPAGE)) {
   2181 				tst_mask = md->pvh_attrs & arm_cache_prefer_mask;
   2182 				SLIST_FOREACH(pv, &md->pvh_list, pv_link)
   2183 					KDASSERT(((tst_mask ^ pv->pv_va) & arm_cache_prefer_mask) == 0);
   2184 			}
   2185 #endif
   2186 			if (SLIST_EMPTY(&md->pvh_list))
   2187 				PMAPCOUNT(vac_color_reuse);
   2188 			else
   2189 				PMAPCOUNT(vac_color_ok);
   2190 
   2191 			/* matching color, just return */
   2192 			KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   2193 			KASSERT((rw_mappings == 0) == !(md->pvh_attrs & PVF_WRITE));
   2194 			return;
   2195 		}
   2196 		KASSERT(SLIST_FIRST(&md->pvh_list) != NULL);
   2197 		KASSERT(SLIST_NEXT(SLIST_FIRST(&md->pvh_list), pv_link) != NULL);
   2198 
   2199 		/* color conflict.  evict from cache. */
   2200 
   2201 		pmap_flush_page(md, pa, PMAP_FLUSH_PRIMARY);
   2202 		md->pvh_attrs &= ~PVF_COLORED;
   2203 		md->pvh_attrs |= PVF_NC;
   2204 		KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   2205 		KASSERT(!(md->pvh_attrs & PVF_MULTCLR));
   2206 		PMAPCOUNT(vac_color_erase);
   2207 	} else if (rw_mappings == 0
   2208 		   && (md->pvh_attrs & PVF_KMPAGE) == 0) {
   2209 		KASSERT((md->pvh_attrs & PVF_WRITE) == 0);
   2210 
   2211 		/*
   2212 		 * If the page has dirty cache lines, clean it.
   2213 		 */
   2214 		if (md->pvh_attrs & PVF_DIRTY)
   2215 			pmap_flush_page(md, pa, PMAP_CLEAN_PRIMARY);
   2216 
   2217 		/*
   2218 		 * If this is the first remapping (we know that there are no
   2219 		 * writeable mappings), then this is a simple color change.
   2220 		 * Otherwise this is a seconary r/o mapping, which means
   2221 		 * we don't have to do anything.
   2222 		 */
   2223 		if (ro_mappings == 1) {
   2224 			KASSERT(((md->pvh_attrs ^ va) & arm_cache_prefer_mask) != 0);
   2225 			md->pvh_attrs &= PAGE_SIZE - 1;
   2226 			md->pvh_attrs |= (va & arm_cache_prefer_mask);
   2227 			PMAPCOUNT(vac_color_change);
   2228 		} else {
   2229 			PMAPCOUNT(vac_color_blind);
   2230 		}
   2231 		md->pvh_attrs |= PVF_MULTCLR;
   2232 		KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   2233 		KASSERT((rw_mappings == 0) == !(md->pvh_attrs & PVF_WRITE));
   2234 		return;
   2235 	} else {
   2236 		if (rw_mappings > 0)
   2237 			md->pvh_attrs |= PVF_WRITE;
   2238 
   2239 		/* color conflict.  evict from cache. */
   2240 		pmap_flush_page(md, pa, PMAP_FLUSH_PRIMARY);
   2241 
   2242 		/* the list can't be empty because this was a enter/modify */
   2243 		pv = SLIST_FIRST(&md->pvh_list);
   2244 		if ((md->pvh_attrs & PVF_KMPAGE) == 0) {
   2245 			KASSERT(pv);
   2246 			/*
   2247 			 * If there's only one mapped page, change color to the
   2248 			 * page's new color and return.  Restore the DIRTY bit
   2249 			 * that was erased by pmap_flush_page.
   2250 			 */
   2251 			if (SLIST_NEXT(pv, pv_link) == NULL) {
   2252 				md->pvh_attrs &= PAGE_SIZE - 1;
   2253 				md->pvh_attrs |= (va & arm_cache_prefer_mask);
   2254 				if (md->pvh_attrs & PVF_DMOD)
   2255 					md->pvh_attrs |= PVF_DIRTY;
   2256 				PMAPCOUNT(vac_color_change);
   2257 				KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   2258 				KASSERT((rw_mappings == 0) == !(md->pvh_attrs & PVF_WRITE));
   2259 				KASSERT(!(md->pvh_attrs & PVF_MULTCLR));
   2260 				return;
   2261 			}
   2262 		}
   2263 		bad_alias = true;
   2264 		md->pvh_attrs &= ~PVF_COLORED;
   2265 		md->pvh_attrs |= PVF_NC;
   2266 		PMAPCOUNT(vac_color_erase);
   2267 		KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   2268 	}
   2269 
   2270   fixup:
   2271 	KASSERT((rw_mappings == 0) == !(md->pvh_attrs & PVF_WRITE));
   2272 
   2273 	/*
   2274 	 * Turn cacheing on/off for all pages.
   2275 	 */
   2276 	SLIST_FOREACH(pv, &md->pvh_list, pv_link) {
   2277 		struct l2_bucket * const l2b = pmap_get_l2_bucket(pv->pv_pmap,
   2278 		    pv->pv_va);
   2279 		KASSERTMSG(l2b != NULL, "%#lx", va);
   2280 		pt_entry_t * const ptep = &l2b->l2b_kva[l2pte_index(pv->pv_va)];
   2281 		const pt_entry_t opte = *ptep;
   2282 		pt_entry_t npte = opte & ~L2_S_CACHE_MASK;
   2283 		if (bad_alias) {
   2284 			pv->pv_flags |= PVF_NC;
   2285 		} else {
   2286 			pv->pv_flags &= ~PVF_NC;
   2287 			npte |= pte_l2_s_cache_mode;
   2288 		}
   2289 
   2290 		if (opte == npte)	/* only update is there's a change */
   2291 			continue;
   2292 
   2293 		if (l2pte_valid_p(npte)) {
   2294 			pmap_tlb_flush_SE(pv->pv_pmap, pv->pv_va, pv->pv_flags);
   2295 		}
   2296 
   2297 		l2pte_set(ptep, npte, opte);
   2298 		PTE_SYNC_CURRENT(pv->pv_pmap, ptep);
   2299 	}
   2300 #endif /* !ARM_MMU_EXTENDED */
   2301 }
   2302 #endif	/* PMAP_CACHE_VIPT */
   2303 
   2304 
   2305 /*
   2306  * Modify pte bits for all ptes corresponding to the given physical address.
   2307  * We use `maskbits' rather than `clearbits' because we're always passing
   2308  * constants and the latter would require an extra inversion at run-time.
   2309  */
   2310 static void
   2311 pmap_clearbit(struct vm_page_md *md, paddr_t pa, u_int maskbits)
   2312 {
   2313 	struct pv_entry *pv;
   2314 #ifdef PMAP_CACHE_VIPT
   2315 	const bool want_syncicache = PV_IS_EXEC_P(md->pvh_attrs);
   2316 #ifdef ARM_MMU_EXTENDED
   2317 	const u_int execbits = (maskbits & PVF_EXEC) ? L2_XS_XN : 0;
   2318 #else
   2319 	const u_int execbits = 0;
   2320 	bool need_vac_me_harder = false;
   2321 	bool need_syncicache = false;
   2322 #endif
   2323 #else
   2324 	const u_int execbits = 0;
   2325 #endif
   2326 
   2327 	NPDEBUG(PDB_BITS,
   2328 	    printf("pmap_clearbit: md %p mask 0x%x\n",
   2329 	    md, maskbits));
   2330 
   2331 #ifdef PMAP_CACHE_VIPT
   2332 	/*
   2333 	 * If we might want to sync the I-cache and we've modified it,
   2334 	 * then we know we definitely need to sync or discard it.
   2335 	 */
   2336 	if (want_syncicache) {
   2337 #ifdef ARM_MMU_EXTENDED
   2338 		if (md->pvh_attrs & PVF_MOD)
   2339 			md->pvh_attrs &= ~PVF_EXEC;
   2340 #else
   2341 		need_syncicache = md->pvh_attrs & PVF_MOD;
   2342 #endif
   2343 	}
   2344 #endif
   2345 	KASSERT(pmap_page_locked_p(md));
   2346 
   2347 	/*
   2348 	 * Clear saved attributes (modify, reference)
   2349 	 */
   2350 	md->pvh_attrs &= ~(maskbits & (PVF_MOD | PVF_REF));
   2351 
   2352 	if (SLIST_EMPTY(&md->pvh_list)) {
   2353 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   2354 		if (need_syncicache) {
   2355 			/*
   2356 			 * No one has it mapped, so just discard it.  The next
   2357 			 * exec remapping will cause it to be synced.
   2358 			 */
   2359 			md->pvh_attrs &= ~PVF_EXEC;
   2360 			PMAPCOUNT(exec_discarded_clearbit);
   2361 		}
   2362 #endif
   2363 		return;
   2364 	}
   2365 
   2366 	/*
   2367 	 * Loop over all current mappings setting/clearing as appropos
   2368 	 */
   2369 	SLIST_FOREACH(pv, &md->pvh_list, pv_link) {
   2370 		pmap_t pm = pv->pv_pmap;
   2371 		const vaddr_t va = pv->pv_va;
   2372 		const u_int oflags = pv->pv_flags;
   2373 #ifndef ARM_MMU_EXTENDED
   2374 		/*
   2375 		 * Kernel entries are unmanaged and as such not to be changed.
   2376 		 */
   2377 		if (PV_IS_KENTRY_P(oflags))
   2378 			continue;
   2379 #endif
   2380 		pv->pv_flags &= ~maskbits;
   2381 
   2382 		pmap_release_page_lock(md);
   2383 		pmap_acquire_pmap_lock(pm);
   2384 
   2385 		struct l2_bucket * const l2b = pmap_get_l2_bucket(pm, va);
   2386 		if (l2b == NULL) {
   2387 			pmap_release_pmap_lock(pm);
   2388 			pmap_acquire_page_lock(md);
   2389 			continue;
   2390 		}
   2391 		KASSERTMSG(l2b != NULL, "%#lx", va);
   2392 
   2393 		pt_entry_t * const ptep = &l2b->l2b_kva[l2pte_index(va)];
   2394 		const pt_entry_t opte = *ptep;
   2395 		pt_entry_t npte = opte | execbits;
   2396 
   2397 #ifdef ARM_MMU_EXTENDED
   2398 		KASSERT((opte & L2_XS_nG) == (pm == pmap_kernel() ? 0 : L2_XS_nG));
   2399 #endif
   2400 
   2401 		NPDEBUG(PDB_BITS,
   2402 		    printf( "%s: pv %p, pm %p, va 0x%08lx, flag 0x%x\n",
   2403 			__func__, pv, pm, va, oflags));
   2404 
   2405 		if (maskbits & (PVF_WRITE|PVF_MOD)) {
   2406 #ifdef PMAP_CACHE_VIVT
   2407 			if ((oflags & PVF_NC)) {
   2408 				/*
   2409 				 * Entry is not cacheable:
   2410 				 *
   2411 				 * Don't turn caching on again if this is a
   2412 				 * modified emulation. This would be
   2413 				 * inconsitent with the settings created by
   2414 				 * pmap_vac_me_harder(). Otherwise, it's safe
   2415 				 * to re-enable cacheing.
   2416 				 *
   2417 				 * There's no need to call pmap_vac_me_harder()
   2418 				 * here: all pages are losing their write
   2419 				 * permission.
   2420 				 */
   2421 				if (maskbits & PVF_WRITE) {
   2422 					npte |= pte_l2_s_cache_mode;
   2423 					pv->pv_flags &= ~PVF_NC;
   2424 				}
   2425 			} else
   2426 			if (l2pte_writable_p(opte)) {
   2427 				/*
   2428 				 * Entry is writable/cacheable: check if pmap
   2429 				 * is current if it is flush it, otherwise it
   2430 				 * won't be in the cache
   2431 				 */
   2432 				pmap_cache_wbinv_page(pm, va,
   2433 				    (maskbits & PVF_REF) != 0,
   2434 				    oflags|PVF_WRITE);
   2435 			}
   2436 #endif
   2437 
   2438 			/* make the pte read only */
   2439 			npte = l2pte_set_readonly(npte);
   2440 
   2441 			pmap_acquire_page_lock(md);
   2442 #ifdef MULTIPROCESSOR
   2443 			pv = pmap_find_pv(md, pm, va);
   2444 #endif
   2445 			if (pv != NULL && (maskbits & oflags & PVF_WRITE)) {
   2446 				/*
   2447 				 * Keep alias accounting up to date
   2448 				 */
   2449 				if (pm == pmap_kernel()) {
   2450 					md->krw_mappings--;
   2451 					md->kro_mappings++;
   2452 				} else {
   2453 					md->urw_mappings--;
   2454 					md->uro_mappings++;
   2455 				}
   2456 #ifdef PMAP_CACHE_VIPT
   2457 				if (arm_cache_prefer_mask != 0) {
   2458 					if (md->urw_mappings + md->krw_mappings == 0) {
   2459 						md->pvh_attrs &= ~PVF_WRITE;
   2460 					} else {
   2461 						PMAP_VALIDATE_MD_PAGE(md);
   2462 					}
   2463 				}
   2464 #ifndef ARM_MMU_EXTENDED
   2465 				if (want_syncicache)
   2466 					need_syncicache = true;
   2467 				need_vac_me_harder = true;
   2468 #endif
   2469 #endif /* PMAP_CACHE_VIPT */
   2470 			}
   2471 			pmap_release_page_lock(md);
   2472 		}
   2473 
   2474 		if (maskbits & PVF_REF) {
   2475 			if (true
   2476 #ifndef ARM_MMU_EXTENDED
   2477 			    && (oflags & PVF_NC) == 0
   2478 #endif
   2479 			    && (maskbits & (PVF_WRITE|PVF_MOD)) == 0
   2480 			    && l2pte_valid_p(npte)) {
   2481 #ifdef PMAP_CACHE_VIVT
   2482 				/*
   2483 				 * Check npte here; we may have already
   2484 				 * done the wbinv above, and the validity
   2485 				 * of the PTE is the same for opte and
   2486 				 * npte.
   2487 				 */
   2488 				pmap_cache_wbinv_page(pm, va, true, oflags);
   2489 #endif
   2490 			}
   2491 
   2492 			/*
   2493 			 * Make the PTE invalid so that we will take a
   2494 			 * page fault the next time the mapping is
   2495 			 * referenced.
   2496 			 */
   2497 			npte &= ~L2_TYPE_MASK;
   2498 			npte |= L2_TYPE_INV;
   2499 		}
   2500 
   2501 		if (npte != opte) {
   2502 			l2pte_reset(ptep);
   2503 			PTE_SYNC(ptep);
   2504 
   2505 			/* Flush the TLB entry if a current pmap. */
   2506 			pmap_tlb_flush_SE(pm, va, oflags);
   2507 
   2508 			l2pte_set(ptep, npte, 0);
   2509 			PTE_SYNC(ptep);
   2510 		}
   2511 
   2512 		pmap_release_pmap_lock(pm);
   2513 		pmap_acquire_page_lock(md);
   2514 
   2515 		NPDEBUG(PDB_BITS,
   2516 		    printf("pmap_clearbit: pm %p va 0x%lx opte 0x%08x npte 0x%08x\n",
   2517 		    pm, va, opte, npte));
   2518 	}
   2519 
   2520 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   2521 	/*
   2522 	 * If we need to sync the I-cache and we haven't done it yet, do it.
   2523 	 */
   2524 	if (need_syncicache) {
   2525 		pmap_release_page_lock(md);
   2526 		pmap_syncicache_page(md, pa);
   2527 		pmap_acquire_page_lock(md);
   2528 		PMAPCOUNT(exec_synced_clearbit);
   2529 	}
   2530 
   2531 	/*
   2532 	 * If we are changing this to read-only, we need to call vac_me_harder
   2533 	 * so we can change all the read-only pages to cacheable.  We pretend
   2534 	 * this as a page deletion.
   2535 	 */
   2536 	if (need_vac_me_harder) {
   2537 		if (md->pvh_attrs & PVF_NC)
   2538 			pmap_vac_me_harder(md, pa, NULL, 0);
   2539 	}
   2540 #endif /* PMAP_CACHE_VIPT && !ARM_MMU_EXTENDED */
   2541 }
   2542 
   2543 /*
   2544  * pmap_clean_page()
   2545  *
   2546  * This is a local function used to work out the best strategy to clean
   2547  * a single page referenced by its entry in the PV table. It's used by
   2548  * pmap_copy_page, pmap_zero_page and maybe some others later on.
   2549  *
   2550  * Its policy is effectively:
   2551  *  o If there are no mappings, we don't bother doing anything with the cache.
   2552  *  o If there is one mapping, we clean just that page.
   2553  *  o If there are multiple mappings, we clean the entire cache.
   2554  *
   2555  * So that some functions can be further optimised, it returns 0 if it didn't
   2556  * clean the entire cache, or 1 if it did.
   2557  *
   2558  * XXX One bug in this routine is that if the pv_entry has a single page
   2559  * mapped at 0x00000000 a whole cache clean will be performed rather than
   2560  * just the 1 page. Since this should not occur in everyday use and if it does
   2561  * it will just result in not the most efficient clean for the page.
   2562  */
   2563 #ifdef PMAP_CACHE_VIVT
   2564 static bool
   2565 pmap_clean_page(struct vm_page_md *md, bool is_src)
   2566 {
   2567 	struct pv_entry *pv;
   2568 	pmap_t pm_to_clean = NULL;
   2569 	bool cache_needs_cleaning = false;
   2570 	vaddr_t page_to_clean = 0;
   2571 	u_int flags = 0;
   2572 
   2573 	/*
   2574 	 * Since we flush the cache each time we change to a different
   2575 	 * user vmspace, we only need to flush the page if it is in the
   2576 	 * current pmap.
   2577 	 */
   2578 	KASSERT(pmap_page_locked_p(md));
   2579 	SLIST_FOREACH(pv, &md->pvh_list, pv_link) {
   2580 		if (pmap_is_current(pv->pv_pmap)) {
   2581 			flags |= pv->pv_flags;
   2582 			/*
   2583 			 * The page is mapped non-cacheable in
   2584 			 * this map.  No need to flush the cache.
   2585 			 */
   2586 			if (pv->pv_flags & PVF_NC) {
   2587 #ifdef DIAGNOSTIC
   2588 				KASSERT(!cache_needs_cleaning);
   2589 #endif
   2590 				break;
   2591 			} else if (is_src && (pv->pv_flags & PVF_WRITE) == 0)
   2592 				continue;
   2593 			if (cache_needs_cleaning) {
   2594 				page_to_clean = 0;
   2595 				break;
   2596 			} else {
   2597 				page_to_clean = pv->pv_va;
   2598 				pm_to_clean = pv->pv_pmap;
   2599 			}
   2600 			cache_needs_cleaning = true;
   2601 		}
   2602 	}
   2603 
   2604 	if (page_to_clean) {
   2605 		pmap_cache_wbinv_page(pm_to_clean, page_to_clean,
   2606 		    !is_src, flags | PVF_REF);
   2607 	} else if (cache_needs_cleaning) {
   2608 		pmap_t const pm = curproc->p_vmspace->vm_map.pmap;
   2609 
   2610 		pmap_cache_wbinv_all(pm, flags);
   2611 		return true;
   2612 	}
   2613 	return false;
   2614 }
   2615 #endif
   2616 
   2617 #ifdef PMAP_CACHE_VIPT
   2618 /*
   2619  * Sync a page with the I-cache.  Since this is a VIPT, we must pick the
   2620  * right cache alias to make sure we flush the right stuff.
   2621  */
   2622 void
   2623 pmap_syncicache_page(struct vm_page_md *md, paddr_t pa)
   2624 {
   2625 	pmap_t kpm = pmap_kernel();
   2626 	const size_t way_size = arm_pcache.icache_type == CACHE_TYPE_PIPT
   2627 	    ? PAGE_SIZE
   2628 	    : arm_pcache.icache_way_size;
   2629 
   2630 	NPDEBUG(PDB_EXEC, printf("pmap_syncicache_page: md=%p (attrs=%#x)\n",
   2631 	    md, md->pvh_attrs));
   2632 	/*
   2633 	 * No need to clean the page if it's non-cached.
   2634 	 */
   2635 #ifndef ARM_MMU_EXTENDED
   2636 	if (md->pvh_attrs & PVF_NC)
   2637 		return;
   2638 	KASSERT(arm_cache_prefer_mask == 0 || md->pvh_attrs & PVF_COLORED);
   2639 #endif
   2640 
   2641 	pt_entry_t * const ptep = cpu_cdst_pte(0);
   2642 	const vaddr_t dstp = cpu_cdstp(0);
   2643 #ifdef __HAVE_MM_MD_DIRECT_MAPPED_PHYS
   2644 	if (way_size <= PAGE_SIZE) {
   2645 		bool ok = false;
   2646 		vaddr_t vdstp = pmap_direct_mapped_phys(pa, &ok, dstp);
   2647 		if (ok) {
   2648 			cpu_icache_sync_range(vdstp, way_size);
   2649 			return;
   2650 		}
   2651 	}
   2652 #endif
   2653 
   2654 	/*
   2655 	 * We don't worry about the color of the exec page, we map the
   2656 	 * same page to pages in the way and then do the icache_sync on
   2657 	 * the entire way making sure we are cleaned.
   2658 	 */
   2659 	const pt_entry_t npte = L2_S_PROTO | pa | pte_l2_s_cache_mode
   2660 	    | L2_S_PROT(PTE_KERNEL, VM_PROT_READ|VM_PROT_WRITE);
   2661 
   2662 	for (size_t i = 0, j = 0; i < way_size;
   2663 	     i += PAGE_SIZE, j += PAGE_SIZE / L2_S_SIZE) {
   2664 		l2pte_reset(ptep + j);
   2665 		PTE_SYNC(ptep + j);
   2666 
   2667 		pmap_tlb_flush_SE(kpm, dstp + i, PVF_REF | PVF_EXEC);
   2668 		/*
   2669 		 * Set up a PTE with to flush these cache lines.
   2670 		 */
   2671 		l2pte_set(ptep + j, npte, 0);
   2672 	}
   2673 	PTE_SYNC_RANGE(ptep, way_size / L2_S_SIZE);
   2674 
   2675 	/*
   2676 	 * Flush it.
   2677 	 */
   2678 	cpu_icache_sync_range(dstp, way_size);
   2679 
   2680 	for (size_t i = 0, j = 0; i < way_size;
   2681 	     i += PAGE_SIZE, j += PAGE_SIZE / L2_S_SIZE) {
   2682 		/*
   2683 		 * Unmap the page(s).
   2684 		 */
   2685 		l2pte_reset(ptep + j);
   2686 		pmap_tlb_flush_SE(kpm, dstp + i, PVF_REF | PVF_EXEC);
   2687 	}
   2688 	PTE_SYNC_RANGE(ptep, way_size / L2_S_SIZE);
   2689 
   2690 	md->pvh_attrs |= PVF_EXEC;
   2691 	PMAPCOUNT(exec_synced);
   2692 }
   2693 
   2694 #ifndef ARM_MMU_EXTENDED
   2695 void
   2696 pmap_flush_page(struct vm_page_md *md, paddr_t pa, enum pmap_flush_op flush)
   2697 {
   2698 	vsize_t va_offset, end_va;
   2699 	bool wbinv_p;
   2700 
   2701 	if (arm_cache_prefer_mask == 0)
   2702 		return;
   2703 
   2704 	switch (flush) {
   2705 	case PMAP_FLUSH_PRIMARY:
   2706 		if (md->pvh_attrs & PVF_MULTCLR) {
   2707 			va_offset = 0;
   2708 			end_va = arm_cache_prefer_mask;
   2709 			md->pvh_attrs &= ~PVF_MULTCLR;
   2710 			PMAPCOUNT(vac_flush_lots);
   2711 		} else {
   2712 			va_offset = md->pvh_attrs & arm_cache_prefer_mask;
   2713 			end_va = va_offset;
   2714 			PMAPCOUNT(vac_flush_one);
   2715 		}
   2716 		/*
   2717 		 * Mark that the page is no longer dirty.
   2718 		 */
   2719 		md->pvh_attrs &= ~PVF_DIRTY;
   2720 		wbinv_p = true;
   2721 		break;
   2722 	case PMAP_FLUSH_SECONDARY:
   2723 		va_offset = 0;
   2724 		end_va = arm_cache_prefer_mask;
   2725 		wbinv_p = true;
   2726 		md->pvh_attrs &= ~PVF_MULTCLR;
   2727 		PMAPCOUNT(vac_flush_lots);
   2728 		break;
   2729 	case PMAP_CLEAN_PRIMARY:
   2730 		va_offset = md->pvh_attrs & arm_cache_prefer_mask;
   2731 		end_va = va_offset;
   2732 		wbinv_p = false;
   2733 		/*
   2734 		 * Mark that the page is no longer dirty.
   2735 		 */
   2736 		if ((md->pvh_attrs & PVF_DMOD) == 0)
   2737 			md->pvh_attrs &= ~PVF_DIRTY;
   2738 		PMAPCOUNT(vac_clean_one);
   2739 		break;
   2740 	default:
   2741 		return;
   2742 	}
   2743 
   2744 	KASSERT(!(md->pvh_attrs & PVF_NC));
   2745 
   2746 	NPDEBUG(PDB_VAC, printf("pmap_flush_page: md=%p (attrs=%#x)\n",
   2747 	    md, md->pvh_attrs));
   2748 
   2749 	const size_t scache_line_size = arm_scache.dcache_line_size;
   2750 
   2751 	for (; va_offset <= end_va; va_offset += PAGE_SIZE) {
   2752 		pt_entry_t * const ptep = cpu_cdst_pte(va_offset);
   2753 		const vaddr_t dstp = cpu_cdstp(va_offset);
   2754 		const pt_entry_t opte = *ptep;
   2755 
   2756 		if (flush == PMAP_FLUSH_SECONDARY
   2757 		    && va_offset == (md->pvh_attrs & arm_cache_prefer_mask))
   2758 			continue;
   2759 
   2760 		pmap_tlb_flush_SE(pmap_kernel(), dstp, PVF_REF | PVF_EXEC);
   2761 		/*
   2762 		 * Set up a PTE with the right coloring to flush
   2763 		 * existing cache entries.
   2764 		 */
   2765 		const pt_entry_t npte = L2_S_PROTO
   2766 		    | pa
   2767 		    | L2_S_PROT(PTE_KERNEL, VM_PROT_READ|VM_PROT_WRITE)
   2768 		    | pte_l2_s_cache_mode;
   2769 		l2pte_set(ptep, npte, opte);
   2770 		PTE_SYNC(ptep);
   2771 
   2772 		/*
   2773 		 * Flush it.  Make sure to flush secondary cache too since
   2774 		 * bus_dma will ignore uncached pages.
   2775 		 */
   2776 		if (scache_line_size != 0) {
   2777 			cpu_dcache_wb_range(dstp, PAGE_SIZE);
   2778 			if (wbinv_p) {
   2779 				cpu_sdcache_wbinv_range(dstp, pa, PAGE_SIZE);
   2780 				cpu_dcache_inv_range(dstp, PAGE_SIZE);
   2781 			} else {
   2782 				cpu_sdcache_wb_range(dstp, pa, PAGE_SIZE);
   2783 			}
   2784 		} else {
   2785 			if (wbinv_p) {
   2786 				cpu_dcache_wbinv_range(dstp, PAGE_SIZE);
   2787 			} else {
   2788 				cpu_dcache_wb_range(dstp, PAGE_SIZE);
   2789 			}
   2790 		}
   2791 
   2792 		/*
   2793 		 * Restore the page table entry since we might have interrupted
   2794 		 * pmap_zero_page or pmap_copy_page which was already using
   2795 		 * this pte.
   2796 		 */
   2797 		if (opte) {
   2798 			l2pte_set(ptep, opte, npte);
   2799 		} else {
   2800 			l2pte_reset(ptep);
   2801 		}
   2802 		PTE_SYNC(ptep);
   2803 		pmap_tlb_flush_SE(pmap_kernel(), dstp, PVF_REF | PVF_EXEC);
   2804 	}
   2805 }
   2806 #endif /* ARM_MMU_EXTENDED */
   2807 #endif /* PMAP_CACHE_VIPT */
   2808 
   2809 /*
   2810  * Routine:	pmap_page_remove
   2811  * Function:
   2812  *		Removes this physical page from
   2813  *		all physical maps in which it resides.
   2814  *		Reflects back modify bits to the pager.
   2815  */
   2816 static void
   2817 pmap_page_remove(struct vm_page_md *md, paddr_t pa)
   2818 {
   2819 	struct l2_bucket *l2b;
   2820 	struct pv_entry *pv;
   2821 	pt_entry_t *ptep;
   2822 #ifndef ARM_MMU_EXTENDED
   2823 	bool flush = false;
   2824 #endif
   2825 	u_int flags = 0;
   2826 
   2827 	NPDEBUG(PDB_FOLLOW,
   2828 	    printf("pmap_page_remove: md %p (0x%08lx)\n", md,
   2829 	    pa));
   2830 
   2831 	struct pv_entry **pvp = &SLIST_FIRST(&md->pvh_list);
   2832 	pmap_acquire_page_lock(md);
   2833 	if (*pvp == NULL) {
   2834 #ifdef PMAP_CACHE_VIPT
   2835 		/*
   2836 		 * We *know* the page contents are about to be replaced.
   2837 		 * Discard the exec contents
   2838 		 */
   2839 		if (PV_IS_EXEC_P(md->pvh_attrs))
   2840 			PMAPCOUNT(exec_discarded_page_protect);
   2841 		md->pvh_attrs &= ~PVF_EXEC;
   2842 		PMAP_VALIDATE_MD_PAGE(md);
   2843 #endif
   2844 		pmap_release_page_lock(md);
   2845 		return;
   2846 	}
   2847 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   2848 	KASSERT(arm_cache_prefer_mask == 0 || pmap_is_page_colored_p(md));
   2849 #endif
   2850 
   2851 	/*
   2852 	 * Clear alias counts
   2853 	 */
   2854 #ifdef PMAP_CACHE_VIVT
   2855 	md->k_mappings = 0;
   2856 #endif
   2857 	md->urw_mappings = md->uro_mappings = 0;
   2858 
   2859 #ifdef PMAP_CACHE_VIVT
   2860 	pmap_clean_page(md, false);
   2861 #endif
   2862 
   2863 	while ((pv = *pvp) != NULL) {
   2864 		pmap_t pm = pv->pv_pmap;
   2865 #ifndef ARM_MMU_EXTENDED
   2866 		if (flush == false && pmap_is_current(pm))
   2867 			flush = true;
   2868 #endif
   2869 
   2870 		if (pm == pmap_kernel()) {
   2871 #ifdef PMAP_CACHE_VIPT
   2872 			/*
   2873 			 * If this was unmanaged mapping, it must be preserved.
   2874 			 * Move it back on the list and advance the end-of-list
   2875 			 * pointer.
   2876 			 */
   2877 			if (PV_IS_KENTRY_P(pv->pv_flags)) {
   2878 				*pvp = pv;
   2879 				pvp = &SLIST_NEXT(pv, pv_link);
   2880 				continue;
   2881 			}
   2882 			if (pv->pv_flags & PVF_WRITE)
   2883 				md->krw_mappings--;
   2884 			else
   2885 				md->kro_mappings--;
   2886 #endif
   2887 			PMAPCOUNT(kernel_unmappings);
   2888 		}
   2889 		*pvp = SLIST_NEXT(pv, pv_link); /* remove from list */
   2890 		PMAPCOUNT(unmappings);
   2891 
   2892 		pmap_release_page_lock(md);
   2893 		pmap_acquire_pmap_lock(pm);
   2894 
   2895 		l2b = pmap_get_l2_bucket(pm, pv->pv_va);
   2896 		KASSERTMSG(l2b != NULL, "%#lx", pv->pv_va);
   2897 
   2898 		ptep = &l2b->l2b_kva[l2pte_index(pv->pv_va)];
   2899 
   2900 		/*
   2901 		 * Update statistics
   2902 		 */
   2903 		--pm->pm_stats.resident_count;
   2904 
   2905 		/* Wired bit */
   2906 		if (pv->pv_flags & PVF_WIRED)
   2907 			--pm->pm_stats.wired_count;
   2908 
   2909 		flags |= pv->pv_flags;
   2910 
   2911 		/*
   2912 		 * Invalidate the PTEs.
   2913 		 */
   2914 		l2pte_reset(ptep);
   2915 		PTE_SYNC_CURRENT(pm, ptep);
   2916 
   2917 #ifdef ARM_MMU_EXTENDED
   2918 		/* XXXNH pmap_tlb_flush_SE()? */
   2919 		pmap_tlb_invalidate_addr(pm, pv->pv_va);
   2920 #endif
   2921 
   2922 		pmap_free_l2_bucket(pm, l2b, PAGE_SIZE / L2_S_SIZE);
   2923 
   2924 		pmap_release_pmap_lock(pm);
   2925 
   2926 		pool_put(&pmap_pv_pool, pv);
   2927 		pmap_acquire_page_lock(md);
   2928 #ifdef MULTIPROCESSOR
   2929 		/*
   2930 		 * Restart of the beginning of the list.
   2931 		 */
   2932 		pvp = &SLIST_FIRST(&md->pvh_list);
   2933 #endif
   2934 	}
   2935 	/*
   2936 	 * if we reach the end of the list and there are still mappings, they
   2937 	 * might be able to be cached now.  And they must be kernel mappings.
   2938 	 */
   2939 	if (!SLIST_EMPTY(&md->pvh_list)) {
   2940 		pmap_vac_me_harder(md, pa, pmap_kernel(), 0);
   2941 	}
   2942 
   2943 #ifdef PMAP_CACHE_VIPT
   2944 	/*
   2945 	 * Its EXEC cache is now gone.
   2946 	 */
   2947 	if (PV_IS_EXEC_P(md->pvh_attrs))
   2948 		PMAPCOUNT(exec_discarded_page_protect);
   2949 	md->pvh_attrs &= ~PVF_EXEC;
   2950 	KASSERT(md->urw_mappings == 0);
   2951 	KASSERT(md->uro_mappings == 0);
   2952 #ifndef ARM_MMU_EXTENDED
   2953 	if (arm_cache_prefer_mask != 0) {
   2954 		if (md->krw_mappings == 0)
   2955 			md->pvh_attrs &= ~PVF_WRITE;
   2956 		PMAP_VALIDATE_MD_PAGE(md);
   2957 	}
   2958 #endif /* ARM_MMU_EXTENDED */
   2959 #endif /* PMAP_CACHE_VIPT */
   2960 	pmap_release_page_lock(md);
   2961 
   2962 #ifndef ARM_MMU_EXTENDED
   2963 	if (flush) {
   2964 		/*
   2965 		 * Note: We can't use pmap_tlb_flush{I,D}() here since that
   2966 		 * would need a subsequent call to pmap_update() to ensure
   2967 		 * curpm->pm_cstate.cs_all is reset. Our callers are not
   2968 		 * required to do that (see pmap(9)), so we can't modify
   2969 		 * the current pmap's state.
   2970 		 */
   2971 		if (PV_BEEN_EXECD(flags))
   2972 			cpu_tlb_flushID();
   2973 		else
   2974 			cpu_tlb_flushD();
   2975 	}
   2976 	cpu_cpwait();
   2977 #endif /* ARM_MMU_EXTENDED */
   2978 }
   2979 
   2980 /*
   2981  * pmap_t pmap_create(void)
   2982  *
   2983  *      Create a new pmap structure from scratch.
   2984  */
   2985 pmap_t
   2986 pmap_create(void)
   2987 {
   2988 	pmap_t pm;
   2989 
   2990 	pm = pool_cache_get(&pmap_cache, PR_WAITOK);
   2991 
   2992 	mutex_init(&pm->pm_obj_lock, MUTEX_DEFAULT, IPL_NONE);
   2993 	uvm_obj_init(&pm->pm_obj, NULL, false, 1);
   2994 	uvm_obj_setlock(&pm->pm_obj, &pm->pm_obj_lock);
   2995 
   2996 	pm->pm_stats.wired_count = 0;
   2997 	pm->pm_stats.resident_count = 1;
   2998 #ifdef ARM_MMU_EXTENDED
   2999 #ifdef MULTIPROCESSOR
   3000 	kcpuset_create(&pm->pm_active, true);
   3001 	kcpuset_create(&pm->pm_onproc, true);
   3002 #endif
   3003 #else
   3004 	pm->pm_cstate.cs_all = 0;
   3005 #endif
   3006 	pmap_alloc_l1(pm);
   3007 
   3008 	/*
   3009 	 * Note: The pool cache ensures that the pm_l2[] array is already
   3010 	 * initialised to zero.
   3011 	 */
   3012 
   3013 	pmap_pinit(pm);
   3014 
   3015 	LIST_INSERT_HEAD(&pmap_pmaps, pm, pm_list);
   3016 
   3017 	return (pm);
   3018 }
   3019 
   3020 u_int
   3021 arm32_mmap_flags(paddr_t pa)
   3022 {
   3023 	/*
   3024 	 * the upper 8 bits in pmap_enter()'s flags are reserved for MD stuff
   3025 	 * and we're using the upper bits in page numbers to pass flags around
   3026 	 * so we might as well use the same bits
   3027 	 */
   3028 	return (u_int)pa & PMAP_MD_MASK;
   3029 }
   3030 /*
   3031  * int pmap_enter(pmap_t pm, vaddr_t va, paddr_t pa, vm_prot_t prot,
   3032  *      u_int flags)
   3033  *
   3034  *      Insert the given physical page (p) at
   3035  *      the specified virtual address (v) in the
   3036  *      target physical map with the protection requested.
   3037  *
   3038  *      NB:  This is the only routine which MAY NOT lazy-evaluate
   3039  *      or lose information.  That is, this routine must actually
   3040  *      insert this page into the given map NOW.
   3041  */
   3042 int
   3043 pmap_enter(pmap_t pm, vaddr_t va, paddr_t pa, vm_prot_t prot, u_int flags)
   3044 {
   3045 	struct l2_bucket *l2b;
   3046 	struct vm_page *pg, *opg;
   3047 	u_int nflags;
   3048 	u_int oflags;
   3049 	const bool kpm_p = (pm == pmap_kernel());
   3050 #ifdef ARM_HAS_VBAR
   3051 	const bool vector_page_p = false;
   3052 #else
   3053 	const bool vector_page_p = (va == vector_page);
   3054 #endif
   3055 
   3056 	UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist);
   3057 
   3058 	UVMHIST_LOG(maphist, " (pm %p va %#x pa %#x prot %#x",
   3059 	    pm, va, pa, prot);
   3060 	UVMHIST_LOG(maphist, "  flag %#x", flags, 0, 0, 0);
   3061 
   3062 	KDASSERT((flags & PMAP_WIRED) == 0 || (flags & VM_PROT_ALL) != 0);
   3063 	KDASSERT(((va | pa) & PGOFSET) == 0);
   3064 
   3065 	/*
   3066 	 * Get a pointer to the page.  Later on in this function, we
   3067 	 * test for a managed page by checking pg != NULL.
   3068 	 */
   3069 	pg = pmap_initialized ? PHYS_TO_VM_PAGE(pa) : NULL;
   3070 
   3071 	nflags = 0;
   3072 	if (prot & VM_PROT_WRITE)
   3073 		nflags |= PVF_WRITE;
   3074 	if (prot & VM_PROT_EXECUTE)
   3075 		nflags |= PVF_EXEC;
   3076 	if (flags & PMAP_WIRED)
   3077 		nflags |= PVF_WIRED;
   3078 
   3079 	pmap_acquire_pmap_lock(pm);
   3080 
   3081 	/*
   3082 	 * Fetch the L2 bucket which maps this page, allocating one if
   3083 	 * necessary for user pmaps.
   3084 	 */
   3085 	if (kpm_p) {
   3086 		l2b = pmap_get_l2_bucket(pm, va);
   3087 	} else {
   3088 		l2b = pmap_alloc_l2_bucket(pm, va);
   3089 	}
   3090 	if (l2b == NULL) {
   3091 		if (flags & PMAP_CANFAIL) {
   3092 			pmap_release_pmap_lock(pm);
   3093 			return (ENOMEM);
   3094 		}
   3095 		panic("pmap_enter: failed to allocate L2 bucket");
   3096 	}
   3097 	pt_entry_t *ptep = &l2b->l2b_kva[l2pte_index(va)];
   3098 	const pt_entry_t opte = *ptep;
   3099 	pt_entry_t npte = pa;
   3100 	oflags = 0;
   3101 
   3102 	if (opte) {
   3103 		/*
   3104 		 * There is already a mapping at this address.
   3105 		 * If the physical address is different, lookup the
   3106 		 * vm_page.
   3107 		 */
   3108 		if (l2pte_pa(opte) != pa)
   3109 			opg = PHYS_TO_VM_PAGE(l2pte_pa(opte));
   3110 		else
   3111 			opg = pg;
   3112 	} else
   3113 		opg = NULL;
   3114 
   3115 	if (pg) {
   3116 		struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   3117 
   3118 		/*
   3119 		 * This is to be a managed mapping.
   3120 		 */
   3121 		pmap_acquire_page_lock(md);
   3122 		if ((flags & VM_PROT_ALL) || (md->pvh_attrs & PVF_REF)) {
   3123 			/*
   3124 			 * - The access type indicates that we don't need
   3125 			 *   to do referenced emulation.
   3126 			 * OR
   3127 			 * - The physical page has already been referenced
   3128 			 *   so no need to re-do referenced emulation here.
   3129 			 */
   3130 			npte |= l2pte_set_readonly(L2_S_PROTO);
   3131 
   3132 			nflags |= PVF_REF;
   3133 
   3134 			if ((prot & VM_PROT_WRITE) != 0 &&
   3135 			    ((flags & VM_PROT_WRITE) != 0 ||
   3136 			     (md->pvh_attrs & PVF_MOD) != 0)) {
   3137 				/*
   3138 				 * This is a writable mapping, and the
   3139 				 * page's mod state indicates it has
   3140 				 * already been modified. Make it
   3141 				 * writable from the outset.
   3142 				 */
   3143 				npte = l2pte_set_writable(npte);
   3144 				nflags |= PVF_MOD;
   3145 			}
   3146 
   3147 #ifdef ARM_MMU_EXTENDED
   3148 			/*
   3149 			 * If the page has been cleaned, then the pvh_attrs
   3150 			 * will have PVF_EXEC set, so mark it execute so we
   3151 			 * don't get an access fault when trying to execute
   3152 			 * from it.
   3153 			 */
   3154 			if (md->pvh_attrs & nflags & PVF_EXEC) {
   3155 				npte &= ~L2_XS_XN;
   3156 			}
   3157 #endif
   3158 		} else {
   3159 			/*
   3160 			 * Need to do page referenced emulation.
   3161 			 */
   3162 			npte |= L2_TYPE_INV;
   3163 		}
   3164 
   3165 		if (flags & ARM32_MMAP_WRITECOMBINE) {
   3166 			npte |= pte_l2_s_wc_mode;
   3167 		} else
   3168 			npte |= pte_l2_s_cache_mode;
   3169 
   3170 		if (pg == opg) {
   3171 			/*
   3172 			 * We're changing the attrs of an existing mapping.
   3173 			 */
   3174 			oflags = pmap_modify_pv(md, pa, pm, va,
   3175 			    PVF_WRITE | PVF_EXEC | PVF_WIRED |
   3176 			    PVF_MOD | PVF_REF, nflags);
   3177 
   3178 #ifdef PMAP_CACHE_VIVT
   3179 			/*
   3180 			 * We may need to flush the cache if we're
   3181 			 * doing rw-ro...
   3182 			 */
   3183 			if (pm->pm_cstate.cs_cache_d &&
   3184 			    (oflags & PVF_NC) == 0 &&
   3185 			    l2pte_writable_p(opte) &&
   3186 			    (prot & VM_PROT_WRITE) == 0)
   3187 				cpu_dcache_wb_range(va, PAGE_SIZE);
   3188 #endif
   3189 		} else {
   3190 			struct pv_entry *pv;
   3191 			/*
   3192 			 * New mapping, or changing the backing page
   3193 			 * of an existing mapping.
   3194 			 */
   3195 			if (opg) {
   3196 				struct vm_page_md *omd = VM_PAGE_TO_MD(opg);
   3197 				paddr_t opa = VM_PAGE_TO_PHYS(opg);
   3198 
   3199 				/*
   3200 				 * Replacing an existing mapping with a new one.
   3201 				 * It is part of our managed memory so we
   3202 				 * must remove it from the PV list
   3203 				 */
   3204 				pv = pmap_remove_pv(omd, opa, pm, va);
   3205 				pmap_vac_me_harder(omd, opa, pm, 0);
   3206 				oflags = pv->pv_flags;
   3207 
   3208 #ifdef PMAP_CACHE_VIVT
   3209 				/*
   3210 				 * If the old mapping was valid (ref/mod
   3211 				 * emulation creates 'invalid' mappings
   3212 				 * initially) then make sure to frob
   3213 				 * the cache.
   3214 				 */
   3215 				if (!(oflags & PVF_NC) && l2pte_valid_p(opte)) {
   3216 					pmap_cache_wbinv_page(pm, va, true,
   3217 					    oflags);
   3218 				}
   3219 #endif
   3220 			} else {
   3221 				pmap_release_page_lock(md);
   3222 				pv = pool_get(&pmap_pv_pool, PR_NOWAIT);
   3223 				if (pv == NULL) {
   3224 					pmap_release_pmap_lock(pm);
   3225 					if ((flags & PMAP_CANFAIL) == 0)
   3226 						panic("pmap_enter: "
   3227 						    "no pv entries");
   3228 
   3229 					pmap_free_l2_bucket(pm, l2b, 0);
   3230 					UVMHIST_LOG(maphist, "  <-- done (ENOMEM)",
   3231 					    0, 0, 0, 0);
   3232 					return (ENOMEM);
   3233 				}
   3234 				pmap_acquire_page_lock(md);
   3235 			}
   3236 
   3237 			pmap_enter_pv(md, pa, pv, pm, va, nflags);
   3238 		}
   3239 		pmap_release_page_lock(md);
   3240 	} else {
   3241 		/*
   3242 		 * We're mapping an unmanaged page.
   3243 		 * These are always readable, and possibly writable, from
   3244 		 * the get go as we don't need to track ref/mod status.
   3245 		 */
   3246 		npte |= l2pte_set_readonly(L2_S_PROTO);
   3247 		if (prot & VM_PROT_WRITE)
   3248 			npte = l2pte_set_writable(npte);
   3249 
   3250 		/*
   3251 		 * Make sure the vector table is mapped cacheable
   3252 		 */
   3253 		if ((vector_page_p && !kpm_p)
   3254 		    || (flags & ARM32_MMAP_CACHEABLE)) {
   3255 			npte |= pte_l2_s_cache_mode;
   3256 #ifdef ARM_MMU_EXTENDED
   3257 			npte &= ~L2_XS_XN;	/* and executable */
   3258 #endif
   3259 		} else if (flags & ARM32_MMAP_WRITECOMBINE) {
   3260 			npte |= pte_l2_s_wc_mode;
   3261 		}
   3262 		if (opg) {
   3263 			/*
   3264 			 * Looks like there's an existing 'managed' mapping
   3265 			 * at this address.
   3266 			 */
   3267 			struct vm_page_md *omd = VM_PAGE_TO_MD(opg);
   3268 			paddr_t opa = VM_PAGE_TO_PHYS(opg);
   3269 
   3270 			pmap_acquire_page_lock(omd);
   3271 			struct pv_entry *pv = pmap_remove_pv(omd, opa, pm, va);
   3272 			pmap_vac_me_harder(omd, opa, pm, 0);
   3273 			oflags = pv->pv_flags;
   3274 			pmap_release_page_lock(omd);
   3275 
   3276 #ifdef PMAP_CACHE_VIVT
   3277 			if (!(oflags & PVF_NC) && l2pte_valid_p(opte)) {
   3278 				pmap_cache_wbinv_page(pm, va, true, oflags);
   3279 			}
   3280 #endif
   3281 			pool_put(&pmap_pv_pool, pv);
   3282 		}
   3283 	}
   3284 
   3285 	/*
   3286 	 * Make sure userland mappings get the right permissions
   3287 	 */
   3288 	if (!vector_page_p && !kpm_p) {
   3289 		npte |= L2_S_PROT_U;
   3290 #ifdef ARM_MMU_EXTENDED
   3291 		npte |= L2_XS_nG;	/* user pages are not global */
   3292 #endif
   3293 	}
   3294 
   3295 	/*
   3296 	 * Keep the stats up to date
   3297 	 */
   3298 	if (opte == 0) {
   3299 		l2b->l2b_occupancy += PAGE_SIZE / L2_S_SIZE;
   3300 		pm->pm_stats.resident_count++;
   3301 	}
   3302 
   3303 	UVMHIST_LOG(maphist, " opte %#x npte %#x", opte, npte, 0, 0);
   3304 
   3305 #if defined(ARM_MMU_EXTENDED)
   3306 	/*
   3307 	 * If exec protection was requested but the page hasn't been synced,
   3308 	 * sync it now and allow execution from it.
   3309 	 */
   3310 	if ((nflags & PVF_EXEC) && (npte & L2_XS_XN)) {
   3311 		struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   3312 		npte &= ~L2_XS_XN;
   3313 		pmap_syncicache_page(md, pa);
   3314 		PMAPCOUNT(exec_synced_map);
   3315 	}
   3316 #endif
   3317 	/*
   3318 	 * If this is just a wiring change, the two PTEs will be
   3319 	 * identical, so there's no need to update the page table.
   3320 	 */
   3321 	if (npte != opte) {
   3322 		l2pte_reset(ptep);
   3323 		PTE_SYNC(ptep);
   3324 		if (l2pte_valid_p(opte)) {
   3325 			pmap_tlb_flush_SE(pm, va, oflags);
   3326 		}
   3327 		l2pte_set(ptep, npte, 0);
   3328 		PTE_SYNC(ptep);
   3329 #ifndef ARM_MMU_EXTENDED
   3330 		bool is_cached = pmap_is_cached(pm);
   3331 		if (is_cached) {
   3332 			/*
   3333 			 * We only need to frob the cache/tlb if this pmap
   3334 			 * is current
   3335 			 */
   3336 			if (!vector_page_p && l2pte_valid_p(npte)) {
   3337 				/*
   3338 				 * This mapping is likely to be accessed as
   3339 				 * soon as we return to userland. Fix up the
   3340 				 * L1 entry to avoid taking another
   3341 				 * page/domain fault.
   3342 				 */
   3343 				pd_entry_t *pdep = pmap_l1_kva(pm)
   3344 				     + l1pte_index(va);
   3345 				pd_entry_t pde = L1_C_PROTO | l2b->l2b_pa
   3346 				    | L1_C_DOM(pmap_domain(pm));
   3347 				if (*pdep != pde) {
   3348 					l1pte_setone(pdep, pde);
   3349 					PTE_SYNC(pdep);
   3350 				}
   3351 			}
   3352 		}
   3353 #endif /* !ARM_MMU_EXTENDED */
   3354 
   3355 #ifndef ARM_MMU_EXTENDED
   3356 		UVMHIST_LOG(maphist, "  is_cached %d cs 0x%08x\n",
   3357 		    is_cached, pm->pm_cstate.cs_all, 0, 0);
   3358 
   3359 		if (pg != NULL) {
   3360 			struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   3361 
   3362 			pmap_acquire_page_lock(md);
   3363 			pmap_vac_me_harder(md, pa, pm, va);
   3364 			pmap_release_page_lock(md);
   3365 		}
   3366 #endif
   3367 	}
   3368 #if defined(PMAP_CACHE_VIPT) && defined(DIAGNOSTIC)
   3369 	if (pg) {
   3370 		struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   3371 
   3372 		pmap_acquire_page_lock(md);
   3373 #ifndef ARM_MMU_EXTENDED
   3374 		KASSERT((md->pvh_attrs & PVF_DMOD) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   3375 #endif
   3376 		PMAP_VALIDATE_MD_PAGE(md);
   3377 		pmap_release_page_lock(md);
   3378 	}
   3379 #endif
   3380 
   3381 	pmap_release_pmap_lock(pm);
   3382 
   3383 	return (0);
   3384 }
   3385 
   3386 /*
   3387  * pmap_remove()
   3388  *
   3389  * pmap_remove is responsible for nuking a number of mappings for a range
   3390  * of virtual address space in the current pmap. To do this efficiently
   3391  * is interesting, because in a number of cases a wide virtual address
   3392  * range may be supplied that contains few actual mappings. So, the
   3393  * optimisations are:
   3394  *  1. Skip over hunks of address space for which no L1 or L2 entry exists.
   3395  *  2. Build up a list of pages we've hit, up to a maximum, so we can
   3396  *     maybe do just a partial cache clean. This path of execution is
   3397  *     complicated by the fact that the cache must be flushed _before_
   3398  *     the PTE is nuked, being a VAC :-)
   3399  *  3. If we're called after UVM calls pmap_remove_all(), we can defer
   3400  *     all invalidations until pmap_update(), since pmap_remove_all() has
   3401  *     already flushed the cache.
   3402  *  4. Maybe later fast-case a single page, but I don't think this is
   3403  *     going to make _that_ much difference overall.
   3404  */
   3405 
   3406 #define	PMAP_REMOVE_CLEAN_LIST_SIZE	3
   3407 
   3408 void
   3409 pmap_remove(pmap_t pm, vaddr_t sva, vaddr_t eva)
   3410 {
   3411 	vaddr_t next_bucket;
   3412 	u_int cleanlist_idx, total, cnt;
   3413 	struct {
   3414 		vaddr_t va;
   3415 		pt_entry_t *ptep;
   3416 	} cleanlist[PMAP_REMOVE_CLEAN_LIST_SIZE];
   3417 	u_int mappings;
   3418 
   3419 	UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist);
   3420 	UVMHIST_LOG(maphist, " (pm=%p, sva=%#x, eva=%#x)", pm, sva, eva, 0);
   3421 
   3422 	/*
   3423 	 * we lock in the pmap => pv_head direction
   3424 	 */
   3425 	pmap_acquire_pmap_lock(pm);
   3426 
   3427 	if (pm->pm_remove_all || !pmap_is_cached(pm)) {
   3428 		cleanlist_idx = PMAP_REMOVE_CLEAN_LIST_SIZE + 1;
   3429 #ifndef ARM_MMU_EXTENDED
   3430 		if (pm->pm_cstate.cs_tlb == 0)
   3431 			pm->pm_remove_all = true;
   3432 #endif
   3433 	} else
   3434 		cleanlist_idx = 0;
   3435 
   3436 	total = 0;
   3437 
   3438 	while (sva < eva) {
   3439 		/*
   3440 		 * Do one L2 bucket's worth at a time.
   3441 		 */
   3442 		next_bucket = L2_NEXT_BUCKET_VA(sva);
   3443 		if (next_bucket > eva)
   3444 			next_bucket = eva;
   3445 
   3446 		struct l2_bucket * const l2b = pmap_get_l2_bucket(pm, sva);
   3447 		if (l2b == NULL) {
   3448 			sva = next_bucket;
   3449 			continue;
   3450 		}
   3451 
   3452 		pt_entry_t *ptep = &l2b->l2b_kva[l2pte_index(sva)];
   3453 
   3454 		for (mappings = 0;
   3455 		     sva < next_bucket;
   3456 		     sva += PAGE_SIZE, ptep += PAGE_SIZE / L2_S_SIZE) {
   3457 			pt_entry_t opte = *ptep;
   3458 
   3459 			if (opte == 0) {
   3460 				/* Nothing here, move along */
   3461 				continue;
   3462 			}
   3463 
   3464 			u_int flags = PVF_REF;
   3465 			paddr_t pa = l2pte_pa(opte);
   3466 			struct vm_page * const pg = PHYS_TO_VM_PAGE(pa);
   3467 
   3468 			/*
   3469 			 * Update flags. In a number of circumstances,
   3470 			 * we could cluster a lot of these and do a
   3471 			 * number of sequential pages in one go.
   3472 			 */
   3473 			if (pg != NULL) {
   3474 				struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   3475 				struct pv_entry *pv;
   3476 
   3477 				pmap_acquire_page_lock(md);
   3478 				pv = pmap_remove_pv(md, pa, pm, sva);
   3479 				pmap_vac_me_harder(md, pa, pm, 0);
   3480 				pmap_release_page_lock(md);
   3481 				if (pv != NULL) {
   3482 					if (pm->pm_remove_all == false) {
   3483 						flags = pv->pv_flags;
   3484 					}
   3485 					pool_put(&pmap_pv_pool, pv);
   3486 				}
   3487 			}
   3488 			mappings += PAGE_SIZE / L2_S_SIZE;
   3489 
   3490 			if (!l2pte_valid_p(opte)) {
   3491 				/*
   3492 				 * Ref/Mod emulation is still active for this
   3493 				 * mapping, therefore it is has not yet been
   3494 				 * accessed. No need to frob the cache/tlb.
   3495 				 */
   3496 				l2pte_reset(ptep);
   3497 				PTE_SYNC_CURRENT(pm, ptep);
   3498  				pmap_tlb_flush_SE(pm, sva, flags);
   3499 				continue;
   3500 			}
   3501 
   3502 #ifdef ARM_MMU_EXTENDED
   3503 			if (pm == pmap_kernel()) {
   3504 				l2pte_reset(ptep);
   3505 				PTE_SYNC(ptep);
   3506  				pmap_tlb_flush_SE(pm, sva, flags);
   3507 				continue;
   3508 			}
   3509 #endif
   3510 			if (cleanlist_idx < PMAP_REMOVE_CLEAN_LIST_SIZE) {
   3511 				/* Add to the clean list. */
   3512 				cleanlist[cleanlist_idx].ptep = ptep;
   3513 				cleanlist[cleanlist_idx].va =
   3514 				    sva | (flags & PVF_EXEC);
   3515 				cleanlist_idx++;
   3516 			} else if (cleanlist_idx == PMAP_REMOVE_CLEAN_LIST_SIZE) {
   3517 				/* Nuke everything if needed. */
   3518 #ifdef PMAP_CACHE_VIVT
   3519 				pmap_cache_wbinv_all(pm, PVF_EXEC);
   3520 #endif
   3521 				/*
   3522 				 * Roll back the previous PTE list,
   3523 				 * and zero out the current PTE.
   3524 				 */
   3525 				for (cnt = 0;
   3526 				     cnt < PMAP_REMOVE_CLEAN_LIST_SIZE; cnt++) {
   3527 					l2pte_reset(cleanlist[cnt].ptep);
   3528 					PTE_SYNC(cleanlist[cnt].ptep);
   3529 				}
   3530 				l2pte_reset(ptep);
   3531 				PTE_SYNC(ptep);
   3532 				cleanlist_idx++;
   3533 				pm->pm_remove_all = true;
   3534 			} else {
   3535 				l2pte_reset(ptep);
   3536 				PTE_SYNC(ptep);
   3537 				if (pm->pm_remove_all == false) {
   3538 					pmap_tlb_flush_SE(pm, sva, flags);
   3539 				}
   3540 			}
   3541 		}
   3542 
   3543 		/*
   3544 		 * Deal with any left overs
   3545 		 */
   3546 		if (cleanlist_idx <= PMAP_REMOVE_CLEAN_LIST_SIZE) {
   3547 			total += cleanlist_idx;
   3548 			for (cnt = 0; cnt < cleanlist_idx; cnt++) {
   3549 				l2pte_reset(cleanlist[cnt].ptep);
   3550 				PTE_SYNC_CURRENT(pm, cleanlist[cnt].ptep);
   3551 #ifdef ARM_MMU_EXTENDED
   3552 				vaddr_t clva = cleanlist[cnt].va;
   3553 				pmap_tlb_flush_SE(pm, clva, PVF_REF);
   3554 #else
   3555 				vaddr_t va = cleanlist[cnt].va;
   3556 				if (pm->pm_cstate.cs_all != 0) {
   3557 					vaddr_t clva = va & ~PAGE_MASK;
   3558 					u_int flags = va & PVF_EXEC;
   3559 #ifdef PMAP_CACHE_VIVT
   3560 					pmap_cache_wbinv_page(pm, clva, true,
   3561 					    PVF_REF | PVF_WRITE | flags);
   3562 #endif
   3563 					pmap_tlb_flush_SE(pm, clva,
   3564 					    PVF_REF | flags);
   3565 				}
   3566 #endif /* ARM_MMU_EXTENDED */
   3567 			}
   3568 
   3569 			/*
   3570 			 * If it looks like we're removing a whole bunch
   3571 			 * of mappings, it's faster to just write-back
   3572 			 * the whole cache now and defer TLB flushes until
   3573 			 * pmap_update() is called.
   3574 			 */
   3575 			if (total <= PMAP_REMOVE_CLEAN_LIST_SIZE)
   3576 				cleanlist_idx = 0;
   3577 			else {
   3578 				cleanlist_idx = PMAP_REMOVE_CLEAN_LIST_SIZE + 1;
   3579 #ifdef PMAP_CACHE_VIVT
   3580 				pmap_cache_wbinv_all(pm, PVF_EXEC);
   3581 #endif
   3582 				pm->pm_remove_all = true;
   3583 			}
   3584 		}
   3585 
   3586 
   3587 		pmap_free_l2_bucket(pm, l2b, mappings);
   3588 		pm->pm_stats.resident_count -= mappings / (PAGE_SIZE/L2_S_SIZE);
   3589 	}
   3590 
   3591 	pmap_release_pmap_lock(pm);
   3592 }
   3593 
   3594 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   3595 static struct pv_entry *
   3596 pmap_kremove_pg(struct vm_page *pg, vaddr_t va)
   3597 {
   3598 	struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   3599 	paddr_t pa = VM_PAGE_TO_PHYS(pg);
   3600 	struct pv_entry *pv;
   3601 
   3602 	KASSERT(arm_cache_prefer_mask == 0 || md->pvh_attrs & (PVF_COLORED|PVF_NC));
   3603 	KASSERT((md->pvh_attrs & PVF_KMPAGE) == 0);
   3604 	KASSERT(pmap_page_locked_p(md));
   3605 
   3606 	pv = pmap_remove_pv(md, pa, pmap_kernel(), va);
   3607 	KASSERTMSG(pv, "pg %p (pa #%lx) va %#lx", pg, pa, va);
   3608 	KASSERT(PV_IS_KENTRY_P(pv->pv_flags));
   3609 
   3610 	/*
   3611 	 * If we are removing a writeable mapping to a cached exec page,
   3612 	 * if it's the last mapping then clear it execness other sync
   3613 	 * the page to the icache.
   3614 	 */
   3615 	if ((md->pvh_attrs & (PVF_NC|PVF_EXEC)) == PVF_EXEC
   3616 	    && (pv->pv_flags & PVF_WRITE) != 0) {
   3617 		if (SLIST_EMPTY(&md->pvh_list)) {
   3618 			md->pvh_attrs &= ~PVF_EXEC;
   3619 			PMAPCOUNT(exec_discarded_kremove);
   3620 		} else {
   3621 			pmap_syncicache_page(md, pa);
   3622 			PMAPCOUNT(exec_synced_kremove);
   3623 		}
   3624 	}
   3625 	pmap_vac_me_harder(md, pa, pmap_kernel(), 0);
   3626 
   3627 	return pv;
   3628 }
   3629 #endif /* PMAP_CACHE_VIPT && !ARM_MMU_EXTENDED */
   3630 
   3631 /*
   3632  * pmap_kenter_pa: enter an unmanaged, wired kernel mapping
   3633  *
   3634  * We assume there is already sufficient KVM space available
   3635  * to do this, as we can't allocate L2 descriptor tables/metadata
   3636  * from here.
   3637  */
   3638 void
   3639 pmap_kenter_pa(vaddr_t va, paddr_t pa, vm_prot_t prot, u_int flags)
   3640 {
   3641 #ifdef PMAP_CACHE_VIVT
   3642 	struct vm_page *pg = (flags & PMAP_KMPAGE) ? PHYS_TO_VM_PAGE(pa) : NULL;
   3643 #endif
   3644 #ifdef PMAP_CACHE_VIPT
   3645 	struct vm_page *pg = PHYS_TO_VM_PAGE(pa);
   3646 	struct vm_page *opg;
   3647 #ifndef ARM_MMU_EXTENDED
   3648 	struct pv_entry *pv = NULL;
   3649 #endif
   3650 #endif
   3651 	struct vm_page_md *md = pg != NULL ? VM_PAGE_TO_MD(pg) : NULL;
   3652 
   3653 	UVMHIST_FUNC(__func__);
   3654 
   3655 	if (pmap_initialized) {
   3656 		UVMHIST_CALLED(maphist);
   3657 		UVMHIST_LOG(maphist, " (va=%#x, pa=%#x, prot=%#x, flags=%#x",
   3658 		    va, pa, prot, flags);
   3659 	}
   3660 
   3661 	pmap_t kpm = pmap_kernel();
   3662 	struct l2_bucket * const l2b = pmap_get_l2_bucket(kpm, va);
   3663 	const size_t l1slot __diagused = l1pte_index(va);
   3664 	KASSERTMSG(l2b != NULL,
   3665 	    "va %#lx pa %#lx prot %d maxkvaddr %#lx: l2 %p l2b %p kva %p",
   3666 	    va, pa, prot, pmap_curmaxkvaddr, kpm->pm_l2[L2_IDX(l1slot)],
   3667 	    kpm->pm_l2[L2_IDX(l1slot)]
   3668 		? &kpm->pm_l2[L2_IDX(l1slot)]->l2_bucket[L2_BUCKET(l1slot)]
   3669 		: NULL,
   3670 	    kpm->pm_l2[L2_IDX(l1slot)]
   3671 		? kpm->pm_l2[L2_IDX(l1slot)]->l2_bucket[L2_BUCKET(l1slot)].l2b_kva
   3672 		: NULL);
   3673 	KASSERT(l2b->l2b_kva != NULL);
   3674 
   3675 	pt_entry_t * const ptep = &l2b->l2b_kva[l2pte_index(va)];
   3676 	const pt_entry_t opte = *ptep;
   3677 
   3678 	if (opte == 0) {
   3679 		PMAPCOUNT(kenter_mappings);
   3680 		l2b->l2b_occupancy += PAGE_SIZE / L2_S_SIZE;
   3681 	} else {
   3682 		PMAPCOUNT(kenter_remappings);
   3683 #ifdef PMAP_CACHE_VIPT
   3684 		opg = PHYS_TO_VM_PAGE(l2pte_pa(opte));
   3685 #if !defined(ARM_MMU_EXTENDED) || defined(DIAGNOSTIC)
   3686 		struct vm_page_md *omd __diagused = VM_PAGE_TO_MD(opg);
   3687 #endif
   3688 		if (opg && arm_cache_prefer_mask != 0) {
   3689 			KASSERT(opg != pg);
   3690 			KASSERT((omd->pvh_attrs & PVF_KMPAGE) == 0);
   3691 			KASSERT((flags & PMAP_KMPAGE) == 0);
   3692 #ifndef ARM_MMU_EXTENDED
   3693 			pmap_acquire_page_lock(omd);
   3694 			pv = pmap_kremove_pg(opg, va);
   3695 			pmap_release_page_lock(omd);
   3696 #endif
   3697 		}
   3698 #endif
   3699 		if (l2pte_valid_p(opte)) {
   3700 			l2pte_reset(ptep);
   3701 			PTE_SYNC(ptep);
   3702 #ifdef PMAP_CACHE_VIVT
   3703 			cpu_dcache_wbinv_range(va, PAGE_SIZE);
   3704 #endif
   3705 			cpu_tlb_flushD_SE(va);
   3706 			cpu_cpwait();
   3707 		}
   3708 	}
   3709 
   3710 	pt_entry_t npte = L2_S_PROTO | pa | L2_S_PROT(PTE_KERNEL, prot)
   3711 	    | ((flags & PMAP_NOCACHE)
   3712 		? 0
   3713 		: ((flags & PMAP_PTE)
   3714 		    ? pte_l2_s_cache_mode_pt : pte_l2_s_cache_mode));
   3715 #ifdef ARM_MMU_EXTENDED
   3716 	if (prot & VM_PROT_EXECUTE)
   3717 		npte &= ~L2_XS_XN;
   3718 #endif
   3719 	l2pte_set(ptep, npte, 0);
   3720 	PTE_SYNC(ptep);
   3721 
   3722 	if (pg) {
   3723 		if (flags & PMAP_KMPAGE) {
   3724 			KASSERT(md->urw_mappings == 0);
   3725 			KASSERT(md->uro_mappings == 0);
   3726 			KASSERT(md->krw_mappings == 0);
   3727 			KASSERT(md->kro_mappings == 0);
   3728 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   3729 			KASSERT(pv == NULL);
   3730 			KASSERT(arm_cache_prefer_mask == 0 || (va & PVF_COLORED) == 0);
   3731 			KASSERT((md->pvh_attrs & PVF_NC) == 0);
   3732 			/* if there is a color conflict, evict from cache. */
   3733 			if (pmap_is_page_colored_p(md)
   3734 			    && ((va ^ md->pvh_attrs) & arm_cache_prefer_mask)) {
   3735 				PMAPCOUNT(vac_color_change);
   3736 				pmap_flush_page(md, pa, PMAP_FLUSH_PRIMARY);
   3737 			} else if (md->pvh_attrs & PVF_MULTCLR) {
   3738 				/*
   3739 				 * If this page has multiple colors, expunge
   3740 				 * them.
   3741 				 */
   3742 				PMAPCOUNT(vac_flush_lots2);
   3743 				pmap_flush_page(md, pa, PMAP_FLUSH_SECONDARY);
   3744 			}
   3745 			/*
   3746 			 * Since this is a KMPAGE, there can be no contention
   3747 			 * for this page so don't lock it.
   3748 			 */
   3749 			md->pvh_attrs &= PAGE_SIZE - 1;
   3750 			md->pvh_attrs |= PVF_KMPAGE | PVF_COLORED | PVF_DIRTY
   3751 			    | (va & arm_cache_prefer_mask);
   3752 #else /* !PMAP_CACHE_VIPT || ARM_MMU_EXTENDED */
   3753 			md->pvh_attrs |= PVF_KMPAGE;
   3754 #endif
   3755 			atomic_inc_32(&pmap_kmpages);
   3756 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   3757 		} else if (arm_cache_prefer_mask != 0) {
   3758 			if (pv == NULL) {
   3759 				pv = pool_get(&pmap_pv_pool, PR_NOWAIT);
   3760 				KASSERT(pv != NULL);
   3761 			}
   3762 			pmap_acquire_page_lock(md);
   3763 			pmap_enter_pv(md, pa, pv, pmap_kernel(), va,
   3764 			    PVF_WIRED | PVF_KENTRY
   3765 			    | (prot & VM_PROT_WRITE ? PVF_WRITE : 0));
   3766 			if ((prot & VM_PROT_WRITE)
   3767 			    && !(md->pvh_attrs & PVF_NC))
   3768 				md->pvh_attrs |= PVF_DIRTY;
   3769 			KASSERT((prot & VM_PROT_WRITE) == 0 || (md->pvh_attrs & (PVF_DIRTY|PVF_NC)));
   3770 			pmap_vac_me_harder(md, pa, pmap_kernel(), va);
   3771 			pmap_release_page_lock(md);
   3772 #endif
   3773 		}
   3774 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   3775 	} else {
   3776 		if (pv != NULL)
   3777 			pool_put(&pmap_pv_pool, pv);
   3778 #endif
   3779 	}
   3780 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   3781 	KASSERT(md == NULL || !pmap_page_locked_p(md));
   3782 #endif
   3783 	if (pmap_initialized) {
   3784 		UVMHIST_LOG(maphist, "  <-- done (ptep %p: %#x -> %#x)",
   3785 		    ptep, opte, npte, 0);
   3786 	}
   3787 
   3788 }
   3789 
   3790 void
   3791 pmap_kremove(vaddr_t va, vsize_t len)
   3792 {
   3793 #ifdef UVMHIST
   3794 	u_int total_mappings = 0;
   3795 #endif
   3796 
   3797 	PMAPCOUNT(kenter_unmappings);
   3798 
   3799 	UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist);
   3800 
   3801 	UVMHIST_LOG(maphist, " (va=%#x, len=%#x)", va, len, 0, 0);
   3802 
   3803 	const vaddr_t eva = va + len;
   3804 
   3805 	while (va < eva) {
   3806 		vaddr_t next_bucket = L2_NEXT_BUCKET_VA(va);
   3807 		if (next_bucket > eva)
   3808 			next_bucket = eva;
   3809 
   3810 		pmap_t kpm = pmap_kernel();
   3811 		struct l2_bucket * const l2b = pmap_get_l2_bucket(kpm, va);
   3812 		KDASSERT(l2b != NULL);
   3813 
   3814 		pt_entry_t * const sptep = &l2b->l2b_kva[l2pte_index(va)];
   3815 		pt_entry_t *ptep = sptep;
   3816 		u_int mappings = 0;
   3817 
   3818 		while (va < next_bucket) {
   3819 			const pt_entry_t opte = *ptep;
   3820 			struct vm_page *opg = PHYS_TO_VM_PAGE(l2pte_pa(opte));
   3821 			if (opg != NULL) {
   3822 				struct vm_page_md *omd = VM_PAGE_TO_MD(opg);
   3823 
   3824 				if (omd->pvh_attrs & PVF_KMPAGE) {
   3825 					KASSERT(omd->urw_mappings == 0);
   3826 					KASSERT(omd->uro_mappings == 0);
   3827 					KASSERT(omd->krw_mappings == 0);
   3828 					KASSERT(omd->kro_mappings == 0);
   3829 					omd->pvh_attrs &= ~PVF_KMPAGE;
   3830 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   3831 					if (arm_cache_prefer_mask != 0) {
   3832 						omd->pvh_attrs &= ~PVF_WRITE;
   3833 					}
   3834 #endif
   3835 					atomic_dec_32(&pmap_kmpages);
   3836 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   3837 				} else if (arm_cache_prefer_mask != 0) {
   3838 					pmap_acquire_page_lock(omd);
   3839 					pool_put(&pmap_pv_pool,
   3840 					    pmap_kremove_pg(opg, va));
   3841 					pmap_release_page_lock(omd);
   3842 #endif
   3843 				}
   3844 			}
   3845 			if (l2pte_valid_p(opte)) {
   3846 				l2pte_reset(ptep);
   3847 				PTE_SYNC(ptep);
   3848 #ifdef PMAP_CACHE_VIVT
   3849 				cpu_dcache_wbinv_range(va, PAGE_SIZE);
   3850 #endif
   3851 				cpu_tlb_flushD_SE(va);
   3852 
   3853 				mappings += PAGE_SIZE / L2_S_SIZE;
   3854 			}
   3855 			va += PAGE_SIZE;
   3856 			ptep += PAGE_SIZE / L2_S_SIZE;
   3857 		}
   3858 		KDASSERTMSG(mappings <= l2b->l2b_occupancy, "%u %u",
   3859 		    mappings, l2b->l2b_occupancy);
   3860 		l2b->l2b_occupancy -= mappings;
   3861 		//PTE_SYNC_RANGE(sptep, (u_int)(ptep - sptep));
   3862 #ifdef UVMHIST
   3863 		total_mappings += mappings;
   3864 #endif
   3865 	}
   3866 	cpu_cpwait();
   3867 	UVMHIST_LOG(maphist, "  <--- done (%u mappings removed)",
   3868 	    total_mappings, 0, 0, 0);
   3869 }
   3870 
   3871 bool
   3872 pmap_extract(pmap_t pm, vaddr_t va, paddr_t *pap)
   3873 {
   3874 	struct l2_dtable *l2;
   3875 	pd_entry_t *pdep, pde;
   3876 	pt_entry_t *ptep, pte;
   3877 	paddr_t pa;
   3878 	u_int l1slot;
   3879 
   3880 	pmap_acquire_pmap_lock(pm);
   3881 
   3882 	l1slot = l1pte_index(va);
   3883 	pdep = pmap_l1_kva(pm) + l1slot;
   3884 	pde = *pdep;
   3885 
   3886 	if (l1pte_section_p(pde)) {
   3887 		/*
   3888 		 * These should only happen for pmap_kernel()
   3889 		 */
   3890 		KDASSERT(pm == pmap_kernel());
   3891 		pmap_release_pmap_lock(pm);
   3892 #if (ARM_MMU_V6 + ARM_MMU_V7) > 0
   3893 		if (l1pte_supersection_p(pde)) {
   3894 			pa = (pde & L1_SS_FRAME) | (va & L1_SS_OFFSET);
   3895 		} else
   3896 #endif
   3897 			pa = (pde & L1_S_FRAME) | (va & L1_S_OFFSET);
   3898 	} else {
   3899 		/*
   3900 		 * Note that we can't rely on the validity of the L1
   3901 		 * descriptor as an indication that a mapping exists.
   3902 		 * We have to look it up in the L2 dtable.
   3903 		 */
   3904 		l2 = pm->pm_l2[L2_IDX(l1slot)];
   3905 
   3906 		if (l2 == NULL ||
   3907 		    (ptep = l2->l2_bucket[L2_BUCKET(l1slot)].l2b_kva) == NULL) {
   3908 			pmap_release_pmap_lock(pm);
   3909 			return false;
   3910 		}
   3911 
   3912 		pte = ptep[l2pte_index(va)];
   3913 		pmap_release_pmap_lock(pm);
   3914 
   3915 		if (pte == 0)
   3916 			return false;
   3917 
   3918 		switch (pte & L2_TYPE_MASK) {
   3919 		case L2_TYPE_L:
   3920 			pa = (pte & L2_L_FRAME) | (va & L2_L_OFFSET);
   3921 			break;
   3922 
   3923 		default:
   3924 			pa = (pte & ~PAGE_MASK) | (va & PAGE_MASK);
   3925 			break;
   3926 		}
   3927 	}
   3928 
   3929 	if (pap != NULL)
   3930 		*pap = pa;
   3931 
   3932 	return true;
   3933 }
   3934 
   3935 void
   3936 pmap_protect(pmap_t pm, vaddr_t sva, vaddr_t eva, vm_prot_t prot)
   3937 {
   3938 	struct l2_bucket *l2b;
   3939 	vaddr_t next_bucket;
   3940 
   3941 	NPDEBUG(PDB_PROTECT,
   3942 	    printf("pmap_protect: pm %p sva 0x%lx eva 0x%lx prot 0x%x\n",
   3943 	    pm, sva, eva, prot));
   3944 
   3945 	if ((prot & VM_PROT_READ) == 0) {
   3946 		pmap_remove(pm, sva, eva);
   3947 		return;
   3948 	}
   3949 
   3950 	if (prot & VM_PROT_WRITE) {
   3951 		/*
   3952 		 * If this is a read->write transition, just ignore it and let
   3953 		 * uvm_fault() take care of it later.
   3954 		 */
   3955 		return;
   3956 	}
   3957 
   3958 	pmap_acquire_pmap_lock(pm);
   3959 
   3960 #ifndef ARM_MMU_EXTENDED
   3961 	const bool flush = eva - sva >= PAGE_SIZE * 4;
   3962 	u_int flags = 0;
   3963 #endif
   3964 	u_int clr_mask = PVF_WRITE | ((prot & VM_PROT_EXECUTE) ? 0 : PVF_EXEC);
   3965 
   3966 	while (sva < eva) {
   3967 		next_bucket = L2_NEXT_BUCKET_VA(sva);
   3968 		if (next_bucket > eva)
   3969 			next_bucket = eva;
   3970 
   3971 		l2b = pmap_get_l2_bucket(pm, sva);
   3972 		if (l2b == NULL) {
   3973 			sva = next_bucket;
   3974 			continue;
   3975 		}
   3976 
   3977 		pt_entry_t *ptep = &l2b->l2b_kva[l2pte_index(sva)];
   3978 
   3979 		while (sva < next_bucket) {
   3980 			const pt_entry_t opte = *ptep;
   3981 			if (l2pte_valid_p(opte) && l2pte_writable_p(opte)) {
   3982 				struct vm_page *pg;
   3983 #ifndef ARM_MMU_EXTENDED
   3984 				u_int f;
   3985 #endif
   3986 
   3987 #ifdef PMAP_CACHE_VIVT
   3988 				/*
   3989 				 * OK, at this point, we know we're doing
   3990 				 * write-protect operation.  If the pmap is
   3991 				 * active, write-back the page.
   3992 				 */
   3993 				pmap_cache_wbinv_page(pm, sva, false,
   3994 				    PVF_REF | PVF_WRITE);
   3995 #endif
   3996 
   3997 				pg = PHYS_TO_VM_PAGE(l2pte_pa(opte));
   3998 				pt_entry_t npte = l2pte_set_readonly(opte);
   3999 				l2pte_reset(ptep);
   4000 				PTE_SYNC(ptep);
   4001 #ifdef ARM_MMU_EXTENDED
   4002 				pmap_tlb_flush_SE(pm, sva, PVF_REF);
   4003 #endif
   4004 				l2pte_set(ptep, npte, 0);
   4005 				PTE_SYNC(ptep);
   4006 
   4007 				if (pg != NULL) {
   4008 					struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   4009 					paddr_t pa = VM_PAGE_TO_PHYS(pg);
   4010 
   4011 					pmap_acquire_page_lock(md);
   4012 #ifndef ARM_MMU_EXTENDED
   4013 					f =
   4014 #endif
   4015 					    pmap_modify_pv(md, pa, pm, sva,
   4016 					       clr_mask, 0);
   4017 					pmap_vac_me_harder(md, pa, pm, sva);
   4018 					pmap_release_page_lock(md);
   4019 #ifndef ARM_MMU_EXTENDED
   4020 				} else {
   4021 					f = PVF_REF | PVF_EXEC;
   4022 				}
   4023 
   4024 				if (flush) {
   4025 					flags |= f;
   4026 				} else {
   4027 					pmap_tlb_flush_SE(pm, sva, f);
   4028 #endif
   4029 				}
   4030 			}
   4031 
   4032 			sva += PAGE_SIZE;
   4033 			ptep += PAGE_SIZE / L2_S_SIZE;
   4034 		}
   4035 	}
   4036 
   4037 #ifndef ARM_MMU_EXTENDED
   4038 	if (flush) {
   4039 		if (PV_BEEN_EXECD(flags)) {
   4040 			pmap_tlb_flushID(pm);
   4041 		} else if (PV_BEEN_REFD(flags)) {
   4042 			pmap_tlb_flushD(pm);
   4043 		}
   4044 	}
   4045 #endif
   4046 
   4047 	pmap_release_pmap_lock(pm);
   4048 }
   4049 
   4050 void
   4051 pmap_icache_sync_range(pmap_t pm, vaddr_t sva, vaddr_t eva)
   4052 {
   4053 	struct l2_bucket *l2b;
   4054 	pt_entry_t *ptep;
   4055 	vaddr_t next_bucket;
   4056 	vsize_t page_size = trunc_page(sva) + PAGE_SIZE - sva;
   4057 
   4058 	NPDEBUG(PDB_EXEC,
   4059 	    printf("pmap_icache_sync_range: pm %p sva 0x%lx eva 0x%lx\n",
   4060 	    pm, sva, eva));
   4061 
   4062 	pmap_acquire_pmap_lock(pm);
   4063 
   4064 	while (sva < eva) {
   4065 		next_bucket = L2_NEXT_BUCKET_VA(sva);
   4066 		if (next_bucket > eva)
   4067 			next_bucket = eva;
   4068 
   4069 		l2b = pmap_get_l2_bucket(pm, sva);
   4070 		if (l2b == NULL) {
   4071 			sva = next_bucket;
   4072 			continue;
   4073 		}
   4074 
   4075 		for (ptep = &l2b->l2b_kva[l2pte_index(sva)];
   4076 		     sva < next_bucket;
   4077 		     sva += page_size,
   4078 		     ptep += PAGE_SIZE / L2_S_SIZE,
   4079 		     page_size = PAGE_SIZE) {
   4080 			if (l2pte_valid_p(*ptep)) {
   4081 				cpu_icache_sync_range(sva,
   4082 				    min(page_size, eva - sva));
   4083 			}
   4084 		}
   4085 	}
   4086 
   4087 	pmap_release_pmap_lock(pm);
   4088 }
   4089 
   4090 void
   4091 pmap_page_protect(struct vm_page *pg, vm_prot_t prot)
   4092 {
   4093 	struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   4094 	paddr_t pa = VM_PAGE_TO_PHYS(pg);
   4095 
   4096 	NPDEBUG(PDB_PROTECT,
   4097 	    printf("pmap_page_protect: md %p (0x%08lx), prot 0x%x\n",
   4098 	    md, pa, prot));
   4099 
   4100 	switch(prot) {
   4101 	case VM_PROT_READ|VM_PROT_WRITE:
   4102 #if defined(ARM_MMU_EXTENDED)
   4103 		pmap_acquire_page_lock(md);
   4104 		pmap_clearbit(md, pa, PVF_EXEC);
   4105 		pmap_release_page_lock(md);
   4106 		break;
   4107 #endif
   4108 	case VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE:
   4109 		break;
   4110 
   4111 	case VM_PROT_READ:
   4112 #if defined(ARM_MMU_EXTENDED)
   4113 		pmap_acquire_page_lock(md);
   4114 		pmap_clearbit(md, pa, PVF_WRITE|PVF_EXEC);
   4115 		pmap_release_page_lock(md);
   4116 		break;
   4117 #endif
   4118 	case VM_PROT_READ|VM_PROT_EXECUTE:
   4119 		pmap_acquire_page_lock(md);
   4120 		pmap_clearbit(md, pa, PVF_WRITE);
   4121 		pmap_release_page_lock(md);
   4122 		break;
   4123 
   4124 	default:
   4125 		pmap_page_remove(md, pa);
   4126 		break;
   4127 	}
   4128 }
   4129 
   4130 /*
   4131  * pmap_clear_modify:
   4132  *
   4133  *	Clear the "modified" attribute for a page.
   4134  */
   4135 bool
   4136 pmap_clear_modify(struct vm_page *pg)
   4137 {
   4138 	struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   4139 	paddr_t pa = VM_PAGE_TO_PHYS(pg);
   4140 	bool rv;
   4141 
   4142 	pmap_acquire_page_lock(md);
   4143 
   4144 	if (md->pvh_attrs & PVF_MOD) {
   4145 		rv = true;
   4146 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   4147 		/*
   4148 		 * If we are going to clear the modified bit and there are
   4149 		 * no other modified bits set, flush the page to memory and
   4150 		 * mark it clean.
   4151 		 */
   4152 		if ((md->pvh_attrs & (PVF_DMOD|PVF_NC)) == PVF_MOD)
   4153 			pmap_flush_page(md, pa, PMAP_CLEAN_PRIMARY);
   4154 #endif
   4155 		pmap_clearbit(md, pa, PVF_MOD);
   4156 	} else {
   4157 		rv = false;
   4158 	}
   4159 	pmap_release_page_lock(md);
   4160 
   4161 	return rv;
   4162 }
   4163 
   4164 /*
   4165  * pmap_clear_reference:
   4166  *
   4167  *	Clear the "referenced" attribute for a page.
   4168  */
   4169 bool
   4170 pmap_clear_reference(struct vm_page *pg)
   4171 {
   4172 	struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   4173 	paddr_t pa = VM_PAGE_TO_PHYS(pg);
   4174 	bool rv;
   4175 
   4176 	pmap_acquire_page_lock(md);
   4177 
   4178 	if (md->pvh_attrs & PVF_REF) {
   4179 		rv = true;
   4180 		pmap_clearbit(md, pa, PVF_REF);
   4181 	} else {
   4182 		rv = false;
   4183 	}
   4184 	pmap_release_page_lock(md);
   4185 
   4186 	return rv;
   4187 }
   4188 
   4189 /*
   4190  * pmap_is_modified:
   4191  *
   4192  *	Test if a page has the "modified" attribute.
   4193  */
   4194 /* See <arm/arm32/pmap.h> */
   4195 
   4196 /*
   4197  * pmap_is_referenced:
   4198  *
   4199  *	Test if a page has the "referenced" attribute.
   4200  */
   4201 /* See <arm/arm32/pmap.h> */
   4202 
   4203 #if defined(ARM_MMU_EXTENDED) && 0
   4204 int
   4205 pmap_prefetchabt_fixup(void *v)
   4206 {
   4207 	struct trapframe * const tf = v;
   4208 	vaddr_t va = trunc_page(tf->tf_pc);
   4209 	int rv = ABORT_FIXUP_FAILED;
   4210 
   4211 	if (!TRAP_USERMODE(tf) && va < VM_MAXUSER_ADDRESS)
   4212 		return rv;
   4213 
   4214 	kpreempt_disable();
   4215 	pmap_t pm = curcpu()->ci_pmap_cur;
   4216 	const size_t l1slot = l1pte_index(va);
   4217 	struct l2_dtable * const l2 = pm->pm_l2[L2_IDX(l1slot)];
   4218 	if (l2 == NULL)
   4219 		goto out;
   4220 
   4221 	struct l2_bucket * const l2b = &l2->l2_bucket[L2_BUCKET(l1slot)];
   4222 	if (l2b->l2b_kva == NULL)
   4223 		goto out;
   4224 
   4225 	/*
   4226 	 * Check the PTE itself.
   4227 	 */
   4228 	pt_entry_t * const ptep = &l2b->l2b_kva[l2pte_index(va)];
   4229 	const pt_entry_t opte = *ptep;
   4230 	if ((opte & L2_S_PROT_U) == 0 || (opte & L2_XS_XN) == 0)
   4231 		goto out;
   4232 
   4233 	paddr_t pa = l2pte_pa(pte);
   4234 	struct vm_page * const pg = PHYS_TO_VM_PAGE(pa);
   4235 	KASSERT(pg != NULL);
   4236 
   4237 	struct vm_page_md * const md = VM_PAGE_TO_MD(pg);
   4238 
   4239 	pmap_acquire_page_lock(md);
   4240 	struct pv_entry * const pv = pmap_find_pv(md, pm, va);
   4241 	KASSERT(pv != NULL);
   4242 
   4243 	if (PV_IS_EXEC_P(pv->pv_flags)) {
   4244 		l2pte_reset(ptep);
   4245 		PTE_SYNC(ptep);
   4246 		pmap_tlb_flush_SE(pm, va, PVF_EXEC | PVF_REF);
   4247 		if (!PV_IS_EXEC_P(md->pvh_attrs)) {
   4248 			pmap_syncicache_page(md, pa);
   4249 		}
   4250 		rv = ABORT_FIXUP_RETURN;
   4251 		l2pte_set(ptep, opte & ~L2_XS_XN, 0);
   4252 		PTE_SYNC(ptep);
   4253 	}
   4254 	pmap_release_page_lock(md);
   4255 
   4256   out:
   4257 	kpreempt_enable();
   4258 	return rv;
   4259 }
   4260 #endif
   4261 
   4262 int
   4263 pmap_fault_fixup(pmap_t pm, vaddr_t va, vm_prot_t ftype, int user)
   4264 {
   4265 	struct l2_dtable *l2;
   4266 	struct l2_bucket *l2b;
   4267 	paddr_t pa;
   4268 	const size_t l1slot = l1pte_index(va);
   4269 	int rv = 0;
   4270 
   4271 	UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist);
   4272 
   4273 	va = trunc_page(va);
   4274 
   4275 	KASSERT(!user || (pm != pmap_kernel()));
   4276 
   4277 	UVMHIST_LOG(maphist, " (pm=%#x, va=%#x, ftype=%#x, user=%d)",
   4278 	    pm, va, ftype, user);
   4279 #ifdef ARM_MMU_EXTENDED
   4280 	UVMHIST_LOG(maphist, " ti=%#x pai=%#x asid=%#x",
   4281 	    cpu_tlb_info(curcpu()), PMAP_PAI(pm, cpu_tlb_info(curcpu())),
   4282 	    PMAP_PAI(pm, cpu_tlb_info(curcpu()))->pai_asid, 0);
   4283 #endif
   4284 
   4285 	pmap_acquire_pmap_lock(pm);
   4286 
   4287 	/*
   4288 	 * If there is no l2_dtable for this address, then the process
   4289 	 * has no business accessing it.
   4290 	 *
   4291 	 * Note: This will catch userland processes trying to access
   4292 	 * kernel addresses.
   4293 	 */
   4294 	l2 = pm->pm_l2[L2_IDX(l1slot)];
   4295 	if (l2 == NULL) {
   4296 		UVMHIST_LOG(maphist, " no l2 for l1slot %#x", l1slot, 0, 0, 0);
   4297 		goto out;
   4298 	}
   4299 
   4300 	/*
   4301 	 * Likewise if there is no L2 descriptor table
   4302 	 */
   4303 	l2b = &l2->l2_bucket[L2_BUCKET(l1slot)];
   4304 	if (l2b->l2b_kva == NULL) {
   4305 		UVMHIST_LOG(maphist, " <-- done (no ptep for l1slot %#x)", l1slot, 0, 0, 0);
   4306 		goto out;
   4307 	}
   4308 
   4309 	/*
   4310 	 * Check the PTE itself.
   4311 	 */
   4312 	pt_entry_t * const ptep = &l2b->l2b_kva[l2pte_index(va)];
   4313 	pt_entry_t const opte = *ptep;
   4314 	if (opte == 0 || (opte & L2_TYPE_MASK) == L2_TYPE_L) {
   4315 		UVMHIST_LOG(maphist, " <-- done (empty pde for l1slot %#x)", l1slot, 0, 0, 0);
   4316 		goto out;
   4317 	}
   4318 
   4319 #ifndef ARM_HAS_VBAR
   4320 	/*
   4321 	 * Catch a userland access to the vector page mapped at 0x0
   4322 	 */
   4323 	if (user && (opte & L2_S_PROT_U) == 0) {
   4324 		UVMHIST_LOG(maphist, " <-- done (vector_page)", 0, 0, 0, 0);
   4325 		goto out;
   4326 	}
   4327 #endif
   4328 
   4329 	pa = l2pte_pa(opte);
   4330 
   4331 	if ((ftype & VM_PROT_WRITE) && !l2pte_writable_p(opte)) {
   4332 		/*
   4333 		 * This looks like a good candidate for "page modified"
   4334 		 * emulation...
   4335 		 */
   4336 		struct pv_entry *pv;
   4337 		struct vm_page *pg;
   4338 
   4339 		/* Extract the physical address of the page */
   4340 		if ((pg = PHYS_TO_VM_PAGE(pa)) == NULL) {
   4341 			UVMHIST_LOG(maphist, " <-- done (mod/ref unmanaged page)", 0, 0, 0, 0);
   4342 			goto out;
   4343 		}
   4344 
   4345 		struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   4346 
   4347 		/* Get the current flags for this page. */
   4348 		pmap_acquire_page_lock(md);
   4349 		pv = pmap_find_pv(md, pm, va);
   4350 		if (pv == NULL || PV_IS_KENTRY_P(pv->pv_flags)) {
   4351 			pmap_release_page_lock(md);
   4352 			UVMHIST_LOG(maphist, " <-- done (mod/ref emul: no PV)", 0, 0, 0, 0);
   4353 			goto out;
   4354 		}
   4355 
   4356 		/*
   4357 		 * Do the flags say this page is writable? If not then it
   4358 		 * is a genuine write fault. If yes then the write fault is
   4359 		 * our fault as we did not reflect the write access in the
   4360 		 * PTE. Now we know a write has occurred we can correct this
   4361 		 * and also set the modified bit
   4362 		 */
   4363 		if ((pv->pv_flags & PVF_WRITE) == 0) {
   4364 			pmap_release_page_lock(md);
   4365 			goto out;
   4366 		}
   4367 
   4368 		md->pvh_attrs |= PVF_REF | PVF_MOD;
   4369 		pv->pv_flags |= PVF_REF | PVF_MOD;
   4370 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   4371 		/*
   4372 		 * If there are cacheable mappings for this page, mark it dirty.
   4373 		 */
   4374 		if ((md->pvh_attrs & PVF_NC) == 0)
   4375 			md->pvh_attrs |= PVF_DIRTY;
   4376 #endif
   4377 #ifdef ARM_MMU_EXTENDED
   4378 		if (md->pvh_attrs & PVF_EXEC) {
   4379 			md->pvh_attrs &= ~PVF_EXEC;
   4380 			PMAPCOUNT(exec_discarded_modfixup);
   4381 		}
   4382 #endif
   4383 		pmap_release_page_lock(md);
   4384 
   4385 		/*
   4386 		 * Re-enable write permissions for the page.  No need to call
   4387 		 * pmap_vac_me_harder(), since this is just a
   4388 		 * modified-emulation fault, and the PVF_WRITE bit isn't
   4389 		 * changing. We've already set the cacheable bits based on
   4390 		 * the assumption that we can write to this page.
   4391 		 */
   4392 		const pt_entry_t npte =
   4393 		    l2pte_set_writable((opte & ~L2_TYPE_MASK) | L2_S_PROTO)
   4394 #ifdef ARM_MMU_EXTENDED
   4395 		    | (pm != pmap_kernel() ? L2_XS_nG : 0)
   4396 #endif
   4397 		    | 0;
   4398 		l2pte_reset(ptep);
   4399 		PTE_SYNC(ptep);
   4400 		pmap_tlb_flush_SE(pm, va,
   4401 		    (ftype & VM_PROT_EXECUTE) ? PVF_EXEC | PVF_REF : PVF_REF);
   4402 		l2pte_set(ptep, npte, 0);
   4403 		PTE_SYNC(ptep);
   4404 		PMAPCOUNT(fixup_mod);
   4405 		rv = 1;
   4406 		UVMHIST_LOG(maphist, " <-- done (mod/ref emul: changed pte from %#x to %#x)",
   4407 		    opte, npte, 0, 0);
   4408 	} else if ((opte & L2_TYPE_MASK) == L2_TYPE_INV) {
   4409 		/*
   4410 		 * This looks like a good candidate for "page referenced"
   4411 		 * emulation.
   4412 		 */
   4413 		struct vm_page *pg;
   4414 
   4415 		/* Extract the physical address of the page */
   4416 		if ((pg = PHYS_TO_VM_PAGE(pa)) == NULL) {
   4417 			UVMHIST_LOG(maphist, " <-- done (ref emul: unmanaged page)", 0, 0, 0, 0);
   4418 			goto out;
   4419 		}
   4420 
   4421 		struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   4422 
   4423 		/* Get the current flags for this page. */
   4424 		pmap_acquire_page_lock(md);
   4425 		struct pv_entry *pv = pmap_find_pv(md, pm, va);
   4426 		if (pv == NULL || PV_IS_KENTRY_P(pv->pv_flags)) {
   4427 			pmap_release_page_lock(md);
   4428 			UVMHIST_LOG(maphist, " <-- done (ref emul no PV)", 0, 0, 0, 0);
   4429 			goto out;
   4430 		}
   4431 
   4432 		md->pvh_attrs |= PVF_REF;
   4433 		pv->pv_flags |= PVF_REF;
   4434 
   4435 		pt_entry_t npte =
   4436 		    l2pte_set_readonly((opte & ~L2_TYPE_MASK) | L2_S_PROTO);
   4437 #ifdef ARM_MMU_EXTENDED
   4438 		if (pm != pmap_kernel()) {
   4439 			npte |= L2_XS_nG;
   4440 		}
   4441 		/*
   4442 		 * If we got called from prefetch abort, then ftype will have
   4443 		 * VM_PROT_EXECUTE set.  Now see if we have no-execute set in
   4444 		 * the PTE.
   4445 		 */
   4446 		if (user && (ftype & VM_PROT_EXECUTE) && (npte & L2_XS_XN)) {
   4447 			/*
   4448 			 * Is this a mapping of an executable page?
   4449 			 */
   4450 			if ((pv->pv_flags & PVF_EXEC) == 0) {
   4451 				pmap_release_page_lock(md);
   4452 				UVMHIST_LOG(maphist, " <-- done (ref emul: no exec)",
   4453 				    0, 0, 0, 0);
   4454 				goto out;
   4455 			}
   4456 			/*
   4457 			 * If we haven't synced the page, do so now.
   4458 			 */
   4459 			if ((md->pvh_attrs & PVF_EXEC) == 0) {
   4460 				UVMHIST_LOG(maphist, " ref emul: syncicache page #%#x",
   4461 				    pa, 0, 0, 0);
   4462 				pmap_syncicache_page(md, pa);
   4463 				PMAPCOUNT(fixup_exec);
   4464 			}
   4465 			npte &= ~L2_XS_XN;
   4466 		}
   4467 #endif /* ARM_MMU_EXTENDED */
   4468 		pmap_release_page_lock(md);
   4469 		l2pte_reset(ptep);
   4470 		PTE_SYNC(ptep);
   4471 		pmap_tlb_flush_SE(pm, va,
   4472 		    (ftype & VM_PROT_EXECUTE) ? PVF_EXEC | PVF_REF : PVF_REF);
   4473 		l2pte_set(ptep, npte, 0);
   4474 		PTE_SYNC(ptep);
   4475 		PMAPCOUNT(fixup_ref);
   4476 		rv = 1;
   4477 		UVMHIST_LOG(maphist, " <-- done (ref emul: changed pte from %#x to %#x)",
   4478 		    opte, npte, 0, 0);
   4479 #ifdef ARM_MMU_EXTENDED
   4480 	} else if (user && (ftype & VM_PROT_EXECUTE) && (opte & L2_XS_XN)) {
   4481 		struct vm_page * const pg = PHYS_TO_VM_PAGE(pa);
   4482 		if (pg == NULL) {
   4483 			UVMHIST_LOG(maphist, " <-- done (unmanaged page)", 0, 0, 0, 0);
   4484 			goto out;
   4485 		}
   4486 
   4487 		struct vm_page_md * const md = VM_PAGE_TO_MD(pg);
   4488 
   4489 		/* Get the current flags for this page. */
   4490 		pmap_acquire_page_lock(md);
   4491 		struct pv_entry * const pv = pmap_find_pv(md, pm, va);
   4492 		if (pv == NULL || (pv->pv_flags & PVF_EXEC) == 0) {
   4493 			pmap_release_page_lock(md);
   4494 			UVMHIST_LOG(maphist, " <-- done (no PV or not EXEC)", 0, 0, 0, 0);
   4495 			goto out;
   4496 		}
   4497 
   4498 		/*
   4499 		 * If we haven't synced the page, do so now.
   4500 		 */
   4501 		if ((md->pvh_attrs & PVF_EXEC) == 0) {
   4502 			UVMHIST_LOG(maphist, "syncicache page #%#x",
   4503 			    pa, 0, 0, 0);
   4504 			pmap_syncicache_page(md, pa);
   4505 		}
   4506 		pmap_release_page_lock(md);
   4507 		/*
   4508 		 * Turn off no-execute.
   4509 		 */
   4510 		KASSERT(opte & L2_XS_nG);
   4511 		l2pte_reset(ptep);
   4512 		PTE_SYNC(ptep);
   4513 		pmap_tlb_flush_SE(pm, va, PVF_EXEC | PVF_REF);
   4514 		l2pte_set(ptep, opte & ~L2_XS_XN, 0);
   4515 		PTE_SYNC(ptep);
   4516 		rv = 1;
   4517 		PMAPCOUNT(fixup_exec);
   4518 		UVMHIST_LOG(maphist, "exec: changed pte from %#x to %#x",
   4519 		    opte, opte & ~L2_XS_XN, 0, 0);
   4520 #endif
   4521 	}
   4522 
   4523 #ifndef ARM_MMU_EXTENDED
   4524 	/*
   4525 	 * We know there is a valid mapping here, so simply
   4526 	 * fix up the L1 if necessary.
   4527 	 */
   4528 	pd_entry_t * const pdep = pmap_l1_kva(pm) + l1slot;
   4529 	pd_entry_t pde = L1_C_PROTO | l2b->l2b_pa | L1_C_DOM(pmap_domain(pm));
   4530 	if (*pdep != pde) {
   4531 		l1pte_setone(pdep, pde);
   4532 		PTE_SYNC(pdep);
   4533 		rv = 1;
   4534 		PMAPCOUNT(fixup_pdes);
   4535 	}
   4536 #endif
   4537 
   4538 #ifdef CPU_SA110
   4539 	/*
   4540 	 * There are bugs in the rev K SA110.  This is a check for one
   4541 	 * of them.
   4542 	 */
   4543 	if (rv == 0 && curcpu()->ci_arm_cputype == CPU_ID_SA110 &&
   4544 	    curcpu()->ci_arm_cpurev < 3) {
   4545 		/* Always current pmap */
   4546 		if (l2pte_valid_p(opte)) {
   4547 			extern int kernel_debug;
   4548 			if (kernel_debug & 1) {
   4549 				struct proc *p = curlwp->l_proc;
   4550 				printf("prefetch_abort: page is already "
   4551 				    "mapped - pte=%p *pte=%08x\n", ptep, opte);
   4552 				printf("prefetch_abort: pc=%08lx proc=%p "
   4553 				    "process=%s\n", va, p, p->p_comm);
   4554 				printf("prefetch_abort: far=%08x fs=%x\n",
   4555 				    cpu_faultaddress(), cpu_faultstatus());
   4556 			}
   4557 #ifdef DDB
   4558 			if (kernel_debug & 2)
   4559 				Debugger();
   4560 #endif
   4561 			rv = 1;
   4562 		}
   4563 	}
   4564 #endif /* CPU_SA110 */
   4565 
   4566 #ifndef ARM_MMU_EXTENDED
   4567 	/*
   4568 	 * If 'rv == 0' at this point, it generally indicates that there is a
   4569 	 * stale TLB entry for the faulting address.  That might be due to a
   4570 	 * wrong setting of pmap_needs_pte_sync.  So set it and retry.
   4571 	 */
   4572 	if (rv == 0
   4573 	    && pm->pm_l1->l1_domain_use_count == 1
   4574 	    && pmap_needs_pte_sync == 0) {
   4575 		pmap_needs_pte_sync = 1;
   4576 		PTE_SYNC(ptep);
   4577 		PMAPCOUNT(fixup_ptesync);
   4578 		rv = 1;
   4579 	}
   4580 #endif
   4581 
   4582 #ifndef MULTIPROCESSOR
   4583 #if defined(DEBUG) || 1
   4584 	/*
   4585 	 * If 'rv == 0' at this point, it generally indicates that there is a
   4586 	 * stale TLB entry for the faulting address. This happens when two or
   4587 	 * more processes are sharing an L1. Since we don't flush the TLB on
   4588 	 * a context switch between such processes, we can take domain faults
   4589 	 * for mappings which exist at the same VA in both processes. EVEN IF
   4590 	 * WE'VE RECENTLY FIXED UP THE CORRESPONDING L1 in pmap_enter(), for
   4591 	 * example.
   4592 	 *
   4593 	 * This is extremely likely to happen if pmap_enter() updated the L1
   4594 	 * entry for a recently entered mapping. In this case, the TLB is
   4595 	 * flushed for the new mapping, but there may still be TLB entries for
   4596 	 * other mappings belonging to other processes in the 1MB range
   4597 	 * covered by the L1 entry.
   4598 	 *
   4599 	 * Since 'rv == 0', we know that the L1 already contains the correct
   4600 	 * value, so the fault must be due to a stale TLB entry.
   4601 	 *
   4602 	 * Since we always need to flush the TLB anyway in the case where we
   4603 	 * fixed up the L1, or frobbed the L2 PTE, we effectively deal with
   4604 	 * stale TLB entries dynamically.
   4605 	 *
   4606 	 * However, the above condition can ONLY happen if the current L1 is
   4607 	 * being shared. If it happens when the L1 is unshared, it indicates
   4608 	 * that other parts of the pmap are not doing their job WRT managing
   4609 	 * the TLB.
   4610 	 */
   4611 	if (rv == 0
   4612 #ifndef ARM_MMU_EXTENDED
   4613 	    && pm->pm_l1->l1_domain_use_count == 1
   4614 #endif
   4615 	    && true) {
   4616 #ifdef DEBUG
   4617 		extern int last_fault_code;
   4618 #else
   4619 		int last_fault_code = ftype & VM_PROT_EXECUTE
   4620 		    ? armreg_ifsr_read()
   4621 		    : armreg_dfsr_read();
   4622 #endif
   4623 		printf("fixup: pm %p, va 0x%lx, ftype %d - nothing to do!\n",
   4624 		    pm, va, ftype);
   4625 		printf("fixup: l2 %p, l2b %p, ptep %p, pte %#x\n",
   4626 		    l2, l2b, ptep, opte);
   4627 
   4628 #ifndef ARM_MMU_EXTENDED
   4629 		printf("fixup: pdep %p, pde %#x, fsr %#x\n",
   4630 		    pdep, pde, last_fault_code);
   4631 #else
   4632 		printf("fixup: pdep %p, pde %#x, ttbcr %#x\n",
   4633 		    &pmap_l1_kva(pm)[l1slot], pmap_l1_kva(pm)[l1slot],
   4634 		   armreg_ttbcr_read());
   4635 		printf("fixup: fsr %#x cpm %p casid %#x contextidr %#x dacr %#x\n",
   4636 		    last_fault_code, curcpu()->ci_pmap_cur,
   4637 		    curcpu()->ci_pmap_asid_cur,
   4638 		    armreg_contextidr_read(), armreg_dacr_read());
   4639 #ifdef _ARM_ARCH_7
   4640 		if (ftype & VM_PROT_WRITE)
   4641 			armreg_ats1cuw_write(va);
   4642 		else
   4643 			armreg_ats1cur_write(va);
   4644 		arm_isb();
   4645 		printf("fixup: par %#x\n", armreg_par_read());
   4646 #endif
   4647 #endif
   4648 #ifdef DDB
   4649 		extern int kernel_debug;
   4650 
   4651 		if (kernel_debug & 2) {
   4652 			pmap_release_pmap_lock(pm);
   4653 #ifdef UVMHIST
   4654 			KERNHIST_DUMP(maphist);
   4655 #endif
   4656 			cpu_Debugger();
   4657 			pmap_acquire_pmap_lock(pm);
   4658 		}
   4659 #endif
   4660 	}
   4661 #endif
   4662 #endif
   4663 
   4664 	rv = 1;
   4665 
   4666 out:
   4667 	pmap_release_pmap_lock(pm);
   4668 
   4669 	return (rv);
   4670 }
   4671 
   4672 /*
   4673  * Routine:	pmap_procwr
   4674  *
   4675  * Function:
   4676  *	Synchronize caches corresponding to [addr, addr+len) in p.
   4677  *
   4678  */
   4679 void
   4680 pmap_procwr(struct proc *p, vaddr_t va, int len)
   4681 {
   4682 	/* We only need to do anything if it is the current process. */
   4683 	if (p == curproc)
   4684 		cpu_icache_sync_range(va, len);
   4685 }
   4686 
   4687 /*
   4688  * Routine:	pmap_unwire
   4689  * Function:	Clear the wired attribute for a map/virtual-address pair.
   4690  *
   4691  * In/out conditions:
   4692  *		The mapping must already exist in the pmap.
   4693  */
   4694 void
   4695 pmap_unwire(pmap_t pm, vaddr_t va)
   4696 {
   4697 	struct l2_bucket *l2b;
   4698 	pt_entry_t *ptep, pte;
   4699 	struct vm_page *pg;
   4700 	paddr_t pa;
   4701 
   4702 	NPDEBUG(PDB_WIRING, printf("pmap_unwire: pm %p, va 0x%08lx\n", pm, va));
   4703 
   4704 	pmap_acquire_pmap_lock(pm);
   4705 
   4706 	l2b = pmap_get_l2_bucket(pm, va);
   4707 	KDASSERT(l2b != NULL);
   4708 
   4709 	ptep = &l2b->l2b_kva[l2pte_index(va)];
   4710 	pte = *ptep;
   4711 
   4712 	/* Extract the physical address of the page */
   4713 	pa = l2pte_pa(pte);
   4714 
   4715 	if ((pg = PHYS_TO_VM_PAGE(pa)) != NULL) {
   4716 		/* Update the wired bit in the pv entry for this page. */
   4717 		struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   4718 
   4719 		pmap_acquire_page_lock(md);
   4720 		(void) pmap_modify_pv(md, pa, pm, va, PVF_WIRED, 0);
   4721 		pmap_release_page_lock(md);
   4722 	}
   4723 
   4724 	pmap_release_pmap_lock(pm);
   4725 }
   4726 
   4727 void
   4728 pmap_activate(struct lwp *l)
   4729 {
   4730 	struct cpu_info * const ci = curcpu();
   4731 	extern int block_userspace_access;
   4732 	pmap_t npm = l->l_proc->p_vmspace->vm_map.pmap;
   4733 #ifdef ARM_MMU_EXTENDED
   4734 	struct pmap_asid_info * const pai = PMAP_PAI(npm, cpu_tlb_info(ci));
   4735 #endif
   4736 
   4737 	UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist);
   4738 
   4739 	UVMHIST_LOG(maphist, "(l=%#x) pm=%#x", l, npm, 0, 0);
   4740 
   4741 	/*
   4742 	 * If activating a non-current lwp or the current lwp is
   4743 	 * already active, just return.
   4744 	 */
   4745 	if (false
   4746 	    || l != curlwp
   4747 #ifdef ARM_MMU_EXTENDED
   4748 	    || (ci->ci_pmap_cur == npm &&
   4749 		(npm == pmap_kernel()
   4750 		 /* || PMAP_PAI_ASIDVALID_P(pai, cpu_tlb_info(ci)) */))
   4751 #else
   4752 	    || npm->pm_activated == true
   4753 #endif
   4754 	    || false) {
   4755 		UVMHIST_LOG(maphist, " <-- (same pmap)", curlwp, l, 0, 0);
   4756 		return;
   4757 	}
   4758 
   4759 #ifndef ARM_MMU_EXTENDED
   4760 	const uint32_t ndacr = (DOMAIN_CLIENT << (PMAP_DOMAIN_KERNEL * 2))
   4761 	    | (DOMAIN_CLIENT << (pmap_domain(npm) * 2));
   4762 
   4763 	/*
   4764 	 * If TTB and DACR are unchanged, short-circuit all the
   4765 	 * TLB/cache management stuff.
   4766 	 */
   4767 	pmap_t opm = ci->ci_lastlwp
   4768 	    ? ci->ci_lastlwp->l_proc->p_vmspace->vm_map.pmap
   4769 	    : NULL;
   4770 	if (opm != NULL) {
   4771 		uint32_t odacr = (DOMAIN_CLIENT << (PMAP_DOMAIN_KERNEL * 2))
   4772 		    | (DOMAIN_CLIENT << (pmap_domain(opm) * 2));
   4773 
   4774 		if (opm->pm_l1 == npm->pm_l1 && odacr == ndacr)
   4775 			goto all_done;
   4776 	}
   4777 #endif /* !ARM_MMU_EXTENDED */
   4778 
   4779 	PMAPCOUNT(activations);
   4780 	block_userspace_access = 1;
   4781 
   4782 #ifndef ARM_MMU_EXTENDED
   4783 	/*
   4784 	 * If switching to a user vmspace which is different to the
   4785 	 * most recent one, and the most recent one is potentially
   4786 	 * live in the cache, we must write-back and invalidate the
   4787 	 * entire cache.
   4788 	 */
   4789 	pmap_t rpm = ci->ci_pmap_lastuser;
   4790 #endif
   4791 
   4792 /*
   4793  * XXXSCW: There's a corner case here which can leave turds in the cache as
   4794  * reported in kern/41058. They're probably left over during tear-down and
   4795  * switching away from an exiting process. Until the root cause is identified
   4796  * and fixed, zap the cache when switching pmaps. This will result in a few
   4797  * unnecessary cache flushes, but that's better than silently corrupting data.
   4798  */
   4799 #ifndef ARM_MMU_EXTENDED
   4800 #if 0
   4801 	if (npm != pmap_kernel() && rpm && npm != rpm &&
   4802 	    rpm->pm_cstate.cs_cache) {
   4803 		rpm->pm_cstate.cs_cache = 0;
   4804 #ifdef PMAP_CACHE_VIVT
   4805 		cpu_idcache_wbinv_all();
   4806 #endif
   4807 	}
   4808 #else
   4809 	if (rpm) {
   4810 		rpm->pm_cstate.cs_cache = 0;
   4811 		if (npm == pmap_kernel())
   4812 			ci->ci_pmap_lastuser = NULL;
   4813 #ifdef PMAP_CACHE_VIVT
   4814 		cpu_idcache_wbinv_all();
   4815 #endif
   4816 	}
   4817 #endif
   4818 
   4819 	/* No interrupts while we frob the TTB/DACR */
   4820 	uint32_t oldirqstate = disable_interrupts(IF32_bits);
   4821 #endif /* !ARM_MMU_EXTENDED */
   4822 
   4823 #ifndef ARM_HAS_VBAR
   4824 	/*
   4825 	 * For ARM_VECTORS_LOW, we MUST, I repeat, MUST fix up the L1
   4826 	 * entry corresponding to 'vector_page' in the incoming L1 table
   4827 	 * before switching to it otherwise subsequent interrupts/exceptions
   4828 	 * (including domain faults!) will jump into hyperspace.
   4829 	 */
   4830 	if (npm->pm_pl1vec != NULL) {
   4831 		cpu_tlb_flushID_SE((u_int)vector_page);
   4832 		cpu_cpwait();
   4833 		*npm->pm_pl1vec = npm->pm_l1vec;
   4834 		PTE_SYNC(npm->pm_pl1vec);
   4835 	}
   4836 #endif
   4837 
   4838 #ifdef ARM_MMU_EXTENDED
   4839 	/*
   4840 	 * Assume that TTBR1 has only global mappings and TTBR0 only has
   4841 	 * non-global mappings.  To prevent speculation from doing evil things
   4842 	 * we disable translation table walks using TTBR0 before setting the
   4843 	 * CONTEXTIDR (ASID) or new TTBR0 value.  Once both are set, table
   4844 	 * walks are reenabled.
   4845 	 */
   4846 	UVMHIST_LOG(maphist, " acquiring asid", 0, 0, 0, 0);
   4847 	const uint32_t old_ttbcr = armreg_ttbcr_read();
   4848 	armreg_ttbcr_write(old_ttbcr | TTBCR_S_PD0);
   4849 	arm_isb();
   4850 	pmap_tlb_asid_acquire(npm, l);
   4851 	UVMHIST_LOG(maphist, " setting ttbr pa=%#x asid=%#x", npm->pm_l1_pa, pai->pai_asid, 0, 0);
   4852 	cpu_setttb(npm->pm_l1_pa, pai->pai_asid);
   4853 	/*
   4854 	 * Now we can reenable tablewalks since the CONTEXTIDR and TTRB0 have
   4855 	 * been updated.
   4856 	 */
   4857 	arm_isb();
   4858 	if (npm != pmap_kernel()) {
   4859 		armreg_ttbcr_write(old_ttbcr & ~TTBCR_S_PD0);
   4860 	}
   4861 	cpu_cpwait();
   4862 	ci->ci_pmap_asid_cur = pai->pai_asid;
   4863 #else
   4864 	cpu_domains(ndacr);
   4865 	if (npm == pmap_kernel() || npm == rpm) {
   4866 		/*
   4867 		 * Switching to a kernel thread, or back to the
   4868 		 * same user vmspace as before... Simply update
   4869 		 * the TTB (no TLB flush required)
   4870 		 */
   4871 		cpu_setttb(npm->pm_l1->l1_physaddr, false);
   4872 		cpu_cpwait();
   4873 	} else {
   4874 		/*
   4875 		 * Otherwise, update TTB and flush TLB
   4876 		 */
   4877 		cpu_context_switch(npm->pm_l1->l1_physaddr);
   4878 		if (rpm != NULL)
   4879 			rpm->pm_cstate.cs_tlb = 0;
   4880 	}
   4881 
   4882 	restore_interrupts(oldirqstate);
   4883 #endif /* ARM_MMU_EXTENDED */
   4884 
   4885 	block_userspace_access = 0;
   4886 
   4887 #ifndef ARM_MMU_EXTENDED
   4888  all_done:
   4889 	/*
   4890 	 * The new pmap is resident. Make sure it's marked
   4891 	 * as resident in the cache/TLB.
   4892 	 */
   4893 	npm->pm_cstate.cs_all = PMAP_CACHE_STATE_ALL;
   4894 	if (npm != pmap_kernel())
   4895 		ci->ci_pmap_lastuser = npm;
   4896 
   4897 	/* The old pmap is not longer active */
   4898 	if (opm != npm) {
   4899 		if (opm != NULL)
   4900 			opm->pm_activated = false;
   4901 
   4902 		/* But the new one is */
   4903 		npm->pm_activated = true;
   4904 	}
   4905 #endif
   4906 	ci->ci_pmap_cur = npm;
   4907 	UVMHIST_LOG(maphist, " <-- done", 0, 0, 0, 0);
   4908 }
   4909 
   4910 void
   4911 pmap_deactivate(struct lwp *l)
   4912 {
   4913 	pmap_t pm = l->l_proc->p_vmspace->vm_map.pmap;
   4914 
   4915 	UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist);
   4916 
   4917 	UVMHIST_LOG(maphist, "(l=%#x) pm=%#x", l, pm, 0, 0);
   4918 
   4919 #ifdef ARM_MMU_EXTENDED
   4920 	kpreempt_disable();
   4921 	struct cpu_info * const ci = curcpu();
   4922 	/*
   4923 	 * Disable translation table walks from TTBR0 while no pmap has been
   4924 	 * activated.
   4925 	 */
   4926 	const uint32_t old_ttbcr = armreg_ttbcr_read();
   4927 	armreg_ttbcr_write(old_ttbcr | TTBCR_S_PD0);
   4928 	arm_isb();
   4929 	pmap_tlb_asid_deactivate(pm);
   4930 	cpu_setttb(pmap_kernel()->pm_l1_pa, KERNEL_PID);
   4931 	ci->ci_pmap_cur = pmap_kernel();
   4932 	kpreempt_enable();
   4933 #else
   4934 	/*
   4935 	 * If the process is exiting, make sure pmap_activate() does
   4936 	 * a full MMU context-switch and cache flush, which we might
   4937 	 * otherwise skip. See PR port-arm/38950.
   4938 	 */
   4939 	if (l->l_proc->p_sflag & PS_WEXIT)
   4940 		curcpu()->ci_lastlwp = NULL;
   4941 
   4942 	pm->pm_activated = false;
   4943 #endif
   4944 	UVMHIST_LOG(maphist, "  <-- done", 0, 0, 0, 0);
   4945 }
   4946 
   4947 void
   4948 pmap_update(pmap_t pm)
   4949 {
   4950 
   4951 	if (pm->pm_remove_all) {
   4952 #ifdef ARM_MMU_EXTENDED
   4953 		KASSERTMSG(curcpu()->ci_pmap_cur != pm || pm->pm_pai[0].pai_asid == curcpu()->ci_pmap_asid_cur, "pmap/asid %p/%#x != %s cur pmap/asid %p/%#x", pm, pm->pm_pai[0].pai_asid, curcpu()->ci_data.cpu_name, curcpu()->ci_pmap_cur, curcpu()->ci_pmap_asid_cur);
   4954 		/*
   4955 		 * Finish up the pmap_remove_all() optimisation by flushing
   4956 		 * all our ASIDs.
   4957 		 */
   4958 		pmap_tlb_asid_release_all(pm);
   4959 #else
   4960 		/*
   4961 		 * Finish up the pmap_remove_all() optimisation by flushing
   4962 		 * the TLB.
   4963 		 */
   4964 		pmap_tlb_flushID(pm);
   4965 #endif
   4966 		pm->pm_remove_all = false;
   4967 	}
   4968 
   4969 #ifdef ARM_MMU_EXTENDED
   4970 #if defined(MULTIPROCESSOR)
   4971 	armreg_bpiallis_write(0);
   4972 #else
   4973 	armreg_bpiall_write(0);
   4974 #endif
   4975 
   4976 #if defined(MULTIPROCESSOR) && PMAP_MAX_TLB > 1
   4977 	u_int pending = atomic_swap_uint(&pmap->pm_shootdown_pending, 0);
   4978 	if (pending && pmap_tlb_shootdown_bystanders(pmap)) {
   4979 		PMAP_COUNT(shootdown_ipis);
   4980 	}
   4981 #endif
   4982 	KASSERTMSG(curcpu()->ci_pmap_cur != pm || pm->pm_pai[0].pai_asid == curcpu()->ci_pmap_asid_cur, "pmap/asid %p/%#x != %s cur pmap/asid %p/%#x", pm, pm->pm_pai[0].pai_asid, curcpu()->ci_data.cpu_name, curcpu()->ci_pmap_cur, curcpu()->ci_pmap_asid_cur);
   4983 #else
   4984 	if (pmap_is_current(pm)) {
   4985 		/*
   4986 		 * If we're dealing with a current userland pmap, move its L1
   4987 		 * to the end of the LRU.
   4988 		 */
   4989 		if (pm != pmap_kernel())
   4990 			pmap_use_l1(pm);
   4991 
   4992 		/*
   4993 		 * We can assume we're done with frobbing the cache/tlb for
   4994 		 * now. Make sure any future pmap ops don't skip cache/tlb
   4995 		 * flushes.
   4996 		 */
   4997 		pm->pm_cstate.cs_all = PMAP_CACHE_STATE_ALL;
   4998 	}
   4999 #endif
   5000 
   5001 	PMAPCOUNT(updates);
   5002 
   5003 	/*
   5004 	 * make sure TLB/cache operations have completed.
   5005 	 */
   5006 	cpu_cpwait();
   5007 }
   5008 
   5009 void
   5010 pmap_remove_all(pmap_t pm)
   5011 {
   5012 
   5013 	/*
   5014 	 * The vmspace described by this pmap is about to be torn down.
   5015 	 * Until pmap_update() is called, UVM will only make calls
   5016 	 * to pmap_remove(). We can make life much simpler by flushing
   5017 	 * the cache now, and deferring TLB invalidation to pmap_update().
   5018 	 */
   5019 #ifdef PMAP_CACHE_VIVT
   5020 	pmap_cache_wbinv_all(pm, PVF_EXEC);
   5021 #endif
   5022 	pm->pm_remove_all = true;
   5023 }
   5024 
   5025 /*
   5026  * Retire the given physical map from service.
   5027  * Should only be called if the map contains no valid mappings.
   5028  */
   5029 void
   5030 pmap_destroy(pmap_t pm)
   5031 {
   5032 	u_int count;
   5033 
   5034 	if (pm == NULL)
   5035 		return;
   5036 
   5037 	if (pm->pm_remove_all) {
   5038 		pmap_tlb_flushID(pm);
   5039 		pm->pm_remove_all = false;
   5040 	}
   5041 
   5042 	/*
   5043 	 * Drop reference count
   5044 	 */
   5045 	mutex_enter(pm->pm_lock);
   5046 	count = --pm->pm_obj.uo_refs;
   5047 	mutex_exit(pm->pm_lock);
   5048 	if (count > 0) {
   5049 #ifndef ARM_MMU_EXTENDED
   5050 		if (pmap_is_current(pm)) {
   5051 			if (pm != pmap_kernel())
   5052 				pmap_use_l1(pm);
   5053 			pm->pm_cstate.cs_all = PMAP_CACHE_STATE_ALL;
   5054 		}
   5055 #endif
   5056 		return;
   5057 	}
   5058 
   5059 	/*
   5060 	 * reference count is zero, free pmap resources and then free pmap.
   5061 	 */
   5062 
   5063 #ifndef ARM_HAS_VBAR
   5064 	if (vector_page < KERNEL_BASE) {
   5065 		KDASSERT(!pmap_is_current(pm));
   5066 
   5067 		/* Remove the vector page mapping */
   5068 		pmap_remove(pm, vector_page, vector_page + PAGE_SIZE);
   5069 		pmap_update(pm);
   5070 	}
   5071 #endif
   5072 
   5073 	LIST_REMOVE(pm, pm_list);
   5074 
   5075 	pmap_free_l1(pm);
   5076 
   5077 #ifdef ARM_MMU_EXTENDED
   5078 #ifdef MULTIPROCESSOR
   5079 	kcpuset_destroy(pm->pm_active);
   5080 	kcpuset_destroy(pm->pm_onproc);
   5081 #endif
   5082 #else
   5083 	struct cpu_info * const ci = curcpu();
   5084 	if (ci->ci_pmap_lastuser == pm)
   5085 		ci->ci_pmap_lastuser = NULL;
   5086 #endif
   5087 
   5088 	uvm_obj_destroy(&pm->pm_obj, false);
   5089 	mutex_destroy(&pm->pm_obj_lock);
   5090 	pool_cache_put(&pmap_cache, pm);
   5091 }
   5092 
   5093 
   5094 /*
   5095  * void pmap_reference(pmap_t pm)
   5096  *
   5097  * Add a reference to the specified pmap.
   5098  */
   5099 void
   5100 pmap_reference(pmap_t pm)
   5101 {
   5102 
   5103 	if (pm == NULL)
   5104 		return;
   5105 
   5106 #ifndef ARM_MMU_EXTENDED
   5107 	pmap_use_l1(pm);
   5108 #endif
   5109 
   5110 	mutex_enter(pm->pm_lock);
   5111 	pm->pm_obj.uo_refs++;
   5112 	mutex_exit(pm->pm_lock);
   5113 }
   5114 
   5115 #if (ARM_MMU_V6 + ARM_MMU_V7) > 0
   5116 
   5117 static struct evcnt pmap_prefer_nochange_ev =
   5118     EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "pmap prefer", "nochange");
   5119 static struct evcnt pmap_prefer_change_ev =
   5120     EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "pmap prefer", "change");
   5121 
   5122 EVCNT_ATTACH_STATIC(pmap_prefer_change_ev);
   5123 EVCNT_ATTACH_STATIC(pmap_prefer_nochange_ev);
   5124 
   5125 void
   5126 pmap_prefer(vaddr_t hint, vaddr_t *vap, int td)
   5127 {
   5128 	vsize_t mask = arm_cache_prefer_mask | (PAGE_SIZE - 1);
   5129 	vaddr_t va = *vap;
   5130 	vaddr_t diff = (hint - va) & mask;
   5131 	if (diff == 0) {
   5132 		pmap_prefer_nochange_ev.ev_count++;
   5133 	} else {
   5134 		pmap_prefer_change_ev.ev_count++;
   5135 		if (__predict_false(td))
   5136 			va -= mask + 1;
   5137 		*vap = va + diff;
   5138 	}
   5139 }
   5140 #endif /* ARM_MMU_V6 | ARM_MMU_V7 */
   5141 
   5142 /*
   5143  * pmap_zero_page()
   5144  *
   5145  * Zero a given physical page by mapping it at a page hook point.
   5146  * In doing the zero page op, the page we zero is mapped cachable, as with
   5147  * StrongARM accesses to non-cached pages are non-burst making writing
   5148  * _any_ bulk data very slow.
   5149  */
   5150 #if (ARM_MMU_GENERIC + ARM_MMU_SA1 + ARM_MMU_V6 + ARM_MMU_V7) != 0
   5151 void
   5152 pmap_zero_page_generic(paddr_t pa)
   5153 {
   5154 #if defined(PMAP_CACHE_VIPT) || defined(DEBUG)
   5155 	struct vm_page *pg = PHYS_TO_VM_PAGE(pa);
   5156 	struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   5157 #endif
   5158 #if defined(PMAP_CACHE_VIPT)
   5159 	/* Choose the last page color it had, if any */
   5160 	const vsize_t va_offset = md->pvh_attrs & arm_cache_prefer_mask;
   5161 #else
   5162 	const vsize_t va_offset = 0;
   5163 #endif
   5164 #if defined(__HAVE_MM_MD_DIRECT_MAPPED_PHYS)
   5165 	/*
   5166 	 * Is this page mapped at its natural color?
   5167 	 * If we have all of memory mapped, then just convert PA to VA.
   5168 	 */
   5169 	bool okcolor = arm_pcache.dcache_type == CACHE_TYPE_PIPT
   5170 	   || va_offset == (pa & arm_cache_prefer_mask);
   5171 	const vaddr_t vdstp = okcolor
   5172 	    ? pmap_direct_mapped_phys(pa, &okcolor, cpu_cdstp(va_offset))
   5173 	    : cpu_cdstp(va_offset);
   5174 #else
   5175 	const bool okcolor = false;
   5176 	const vaddr_t vdstp = cpu_cdstp(va_offset);
   5177 #endif
   5178 	pt_entry_t * const ptep = cpu_cdst_pte(va_offset);
   5179 
   5180 
   5181 #ifdef DEBUG
   5182 	if (!SLIST_EMPTY(&md->pvh_list))
   5183 		panic("pmap_zero_page: page has mappings");
   5184 #endif
   5185 
   5186 	KDASSERT((pa & PGOFSET) == 0);
   5187 
   5188 	if (!okcolor) {
   5189 		/*
   5190 		 * Hook in the page, zero it, and purge the cache for that
   5191 		 * zeroed page. Invalidate the TLB as needed.
   5192 		 */
   5193 		const pt_entry_t npte = L2_S_PROTO | pa | pte_l2_s_cache_mode
   5194 		    | L2_S_PROT(PTE_KERNEL, VM_PROT_WRITE);
   5195 		l2pte_set(ptep, npte, 0);
   5196 		PTE_SYNC(ptep);
   5197 		cpu_tlb_flushD_SE(vdstp);
   5198 		cpu_cpwait();
   5199 #if defined(__HAVE_MM_MD_DIRECT_MAPPED_PHYS) && defined(PMAP_CACHE_VIPT) \
   5200     && !defined(ARM_MMU_EXTENDED)
   5201 		/*
   5202 		 * If we are direct-mapped and our color isn't ok, then before
   5203 		 * we bzero the page invalidate its contents from the cache and
   5204 		 * reset the color to its natural color.
   5205 		 */
   5206 		cpu_dcache_inv_range(vdstp, PAGE_SIZE);
   5207 		md->pvh_attrs &= ~arm_cache_prefer_mask;
   5208 		md->pvh_attrs |= (pa & arm_cache_prefer_mask);
   5209 #endif
   5210 	}
   5211 	bzero_page(vdstp);
   5212 	if (!okcolor) {
   5213 		/*
   5214 		 * Unmap the page.
   5215 		 */
   5216 		l2pte_reset(ptep);
   5217 		PTE_SYNC(ptep);
   5218 		cpu_tlb_flushD_SE(vdstp);
   5219 #ifdef PMAP_CACHE_VIVT
   5220 		cpu_dcache_wbinv_range(vdstp, PAGE_SIZE);
   5221 #endif
   5222 	}
   5223 #ifdef PMAP_CACHE_VIPT
   5224 	/*
   5225 	 * This page is now cache resident so it now has a page color.
   5226 	 * Any contents have been obliterated so clear the EXEC flag.
   5227 	 */
   5228 #ifndef ARM_MMU_EXTENDED
   5229 	if (!pmap_is_page_colored_p(md)) {
   5230 		PMAPCOUNT(vac_color_new);
   5231 		md->pvh_attrs |= PVF_COLORED;
   5232 	}
   5233 	md->pvh_attrs |= PVF_DIRTY;
   5234 #endif
   5235 	if (PV_IS_EXEC_P(md->pvh_attrs)) {
   5236 		md->pvh_attrs &= ~PVF_EXEC;
   5237 		PMAPCOUNT(exec_discarded_zero);
   5238 	}
   5239 #endif
   5240 }
   5241 #endif /* (ARM_MMU_GENERIC + ARM_MMU_SA1 + ARM_MMU_V6) != 0 */
   5242 
   5243 #if ARM_MMU_XSCALE == 1
   5244 void
   5245 pmap_zero_page_xscale(paddr_t pa)
   5246 {
   5247 #ifdef DEBUG
   5248 	struct vm_page *pg = PHYS_TO_VM_PAGE(pa);
   5249 	struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   5250 
   5251 	if (!SLIST_EMPTY(&md->pvh_list))
   5252 		panic("pmap_zero_page: page has mappings");
   5253 #endif
   5254 
   5255 	KDASSERT((pa & PGOFSET) == 0);
   5256 
   5257 	/*
   5258 	 * Hook in the page, zero it, and purge the cache for that
   5259 	 * zeroed page. Invalidate the TLB as needed.
   5260 	 */
   5261 
   5262 	pt_entry_t npte = L2_S_PROTO | pa |
   5263 	    L2_S_PROT(PTE_KERNEL, VM_PROT_WRITE) |
   5264 	    L2_C | L2_XS_T_TEX(TEX_XSCALE_X);	/* mini-data */
   5265 	l2pte_set(cdst_pte, npte, 0);
   5266 	PTE_SYNC(cdst_pte);
   5267 	cpu_tlb_flushD_SE(cdstp);
   5268 	cpu_cpwait();
   5269 	bzero_page(cdstp);
   5270 	xscale_cache_clean_minidata();
   5271 	l2pte_reset(cdst_pte);
   5272 	PTE_SYNC(cdst_pte);
   5273 }
   5274 #endif /* ARM_MMU_XSCALE == 1 */
   5275 
   5276 /* pmap_pageidlezero()
   5277  *
   5278  * The same as above, except that we assume that the page is not
   5279  * mapped.  This means we never have to flush the cache first.  Called
   5280  * from the idle loop.
   5281  */
   5282 bool
   5283 pmap_pageidlezero(paddr_t pa)
   5284 {
   5285 	bool rv = true;
   5286 #if defined(PMAP_CACHE_VIPT) || defined(DEBUG)
   5287 	struct vm_page * const pg = PHYS_TO_VM_PAGE(pa);
   5288 	struct vm_page_md *md = VM_PAGE_TO_MD(pg);
   5289 #endif
   5290 #ifdef PMAP_CACHE_VIPT
   5291 	/* Choose the last page color it had, if any */
   5292 	const vsize_t va_offset = md->pvh_attrs & arm_cache_prefer_mask;
   5293 #else
   5294 	const vsize_t va_offset = 0;
   5295 #endif
   5296 #ifdef __HAVE_MM_MD_DIRECT_MAPPED_PHYS
   5297 	bool okcolor = arm_pcache.dcache_type == CACHE_TYPE_PIPT
   5298 	   || va_offset == (pa & arm_cache_prefer_mask);
   5299 	const vaddr_t vdstp = okcolor
   5300 	    ? pmap_direct_mapped_phys(pa, &okcolor, cpu_cdstp(va_offset))
   5301 	    : cpu_cdstp(va_offset);
   5302 #else
   5303 	const bool okcolor = false;
   5304 	const vaddr_t vdstp = cpu_cdstp(va_offset);
   5305 #endif
   5306 	pt_entry_t * const ptep = cpu_cdst_pte(va_offset);
   5307 
   5308 
   5309 #ifdef DEBUG
   5310 	if (!SLIST_EMPTY(&md->pvh_list))
   5311 		panic("pmap_pageidlezero: page has mappings");
   5312 #endif
   5313 
   5314 	KDASSERT((pa & PGOFSET) == 0);
   5315 
   5316 	if (!okcolor) {
   5317 		/*
   5318 		 * Hook in the page, zero it, and purge the cache for that
   5319 		 * zeroed page. Invalidate the TLB as needed.
   5320 		 */
   5321 		const pt_entry_t npte = L2_S_PROTO | pa |
   5322 		    L2_S_PROT(PTE_KERNEL, VM_PROT_WRITE) | pte_l2_s_cache_mode;
   5323 		l2pte_set(ptep, npte, 0);
   5324 		PTE_SYNC(ptep);
   5325 		cpu_tlb_flushD_SE(vdstp);
   5326 		cpu_cpwait();
   5327 	}
   5328 
   5329 	uint64_t *ptr = (uint64_t *)vdstp;
   5330 	for (size_t i = 0; i < PAGE_SIZE / sizeof(*ptr); i++) {
   5331 		if (sched_curcpu_runnable_p() != 0) {
   5332 			/*
   5333 			 * A process has become ready.  Abort now,
   5334 			 * so we don't keep it waiting while we
   5335 			 * do slow memory access to finish this
   5336 			 * page.
   5337 			 */
   5338 			rv = false;
   5339 			break;
   5340 		}
   5341 		*ptr++ = 0;
   5342 	}
   5343 
   5344 #ifdef PMAP_CACHE_VIVT
   5345 	if (rv)
   5346 		/*
   5347 		 * if we aborted we'll rezero this page again later so don't
   5348 		 * purge it unless we finished it
   5349 		 */
   5350 		cpu_dcache_wbinv_range(vdstp, PAGE_SIZE);
   5351 #elif defined(PMAP_CACHE_VIPT)
   5352 	/*
   5353 	 * This page is now cache resident so it now has a page color.
   5354 	 * Any contents have been obliterated so clear the EXEC flag.
   5355 	 */
   5356 #ifndef ARM_MMU_EXTENDED
   5357 	if (!pmap_is_page_colored_p(md)) {
   5358 		PMAPCOUNT(vac_color_new);
   5359 		md->pvh_attrs |= PVF_COLORED;
   5360 	}
   5361 #endif
   5362 	if (PV_IS_EXEC_P(md->pvh_attrs)) {
   5363 		md->pvh_attrs &= ~PVF_EXEC;
   5364 		PMAPCOUNT(exec_discarded_zero);
   5365 	}
   5366 #endif
   5367 	/*
   5368 	 * Unmap the page.
   5369 	 */
   5370 	if (!okcolor) {
   5371 		l2pte_reset(ptep);
   5372 		PTE_SYNC(ptep);
   5373 		cpu_tlb_flushD_SE(vdstp);
   5374 	}
   5375 
   5376 	return rv;
   5377 }
   5378 
   5379 /*
   5380  * pmap_copy_page()
   5381  *
   5382  * Copy one physical page into another, by mapping the pages into
   5383  * hook points. The same comment regarding cachability as in
   5384  * pmap_zero_page also applies here.
   5385  */
   5386 #if (ARM_MMU_GENERIC + ARM_MMU_SA1 + ARM_MMU_V6 + ARM_MMU_V7) != 0
   5387 void
   5388 pmap_copy_page_generic(paddr_t src, paddr_t dst)
   5389 {
   5390 	struct vm_page * const src_pg = PHYS_TO_VM_PAGE(src);
   5391 	struct vm_page_md *src_md = VM_PAGE_TO_MD(src_pg);
   5392 #if defined(PMAP_CACHE_VIPT) || defined(DEBUG)
   5393 	struct vm_page * const dst_pg = PHYS_TO_VM_PAGE(dst);
   5394 	struct vm_page_md *dst_md = VM_PAGE_TO_MD(dst_pg);
   5395 #endif
   5396 #ifdef PMAP_CACHE_VIPT
   5397 	const vsize_t src_va_offset = src_md->pvh_attrs & arm_cache_prefer_mask;
   5398 	const vsize_t dst_va_offset = dst_md->pvh_attrs & arm_cache_prefer_mask;
   5399 #else
   5400 	const vsize_t src_va_offset = 0;
   5401 	const vsize_t dst_va_offset = 0;
   5402 #endif
   5403 #if defined(__HAVE_MM_MD_DIRECT_MAPPED_PHYS)
   5404 	/*
   5405 	 * Is this page mapped at its natural color?
   5406 	 * If we have all of memory mapped, then just convert PA to VA.
   5407 	 */
   5408 	bool src_okcolor = arm_pcache.dcache_type == CACHE_TYPE_PIPT
   5409 	    || src_va_offset == (src & arm_cache_prefer_mask);
   5410 	bool dst_okcolor = arm_pcache.dcache_type == CACHE_TYPE_PIPT
   5411 	    || dst_va_offset == (dst & arm_cache_prefer_mask);
   5412 	const vaddr_t vsrcp = src_okcolor
   5413 	    ? pmap_direct_mapped_phys(src, &src_okcolor,
   5414 		cpu_csrcp(src_va_offset))
   5415 	    : cpu_csrcp(src_va_offset);
   5416 	const vaddr_t vdstp = pmap_direct_mapped_phys(dst, &dst_okcolor,
   5417 	    cpu_cdstp(dst_va_offset));
   5418 #else
   5419 	const bool src_okcolor = false;
   5420 	const bool dst_okcolor = false;
   5421 	const vaddr_t vsrcp = cpu_csrcp(src_va_offset);
   5422 	const vaddr_t vdstp = cpu_cdstp(dst_va_offset);
   5423 #endif
   5424 	pt_entry_t * const src_ptep = cpu_csrc_pte(src_va_offset);
   5425 	pt_entry_t * const dst_ptep = cpu_cdst_pte(dst_va_offset);
   5426 
   5427 #ifdef DEBUG
   5428 	if (!SLIST_EMPTY(&dst_md->pvh_list))
   5429 		panic("pmap_copy_page: dst page has mappings");
   5430 #endif
   5431 
   5432 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   5433 	KASSERT(arm_cache_prefer_mask == 0 || src_md->pvh_attrs & (PVF_COLORED|PVF_NC));
   5434 #endif
   5435 	KDASSERT((src & PGOFSET) == 0);
   5436 	KDASSERT((dst & PGOFSET) == 0);
   5437 
   5438 	/*
   5439 	 * Clean the source page.  Hold the source page's lock for
   5440 	 * the duration of the copy so that no other mappings can
   5441 	 * be created while we have a potentially aliased mapping.
   5442 	 */
   5443 #ifdef PMAP_CACHE_VIVT
   5444 	pmap_acquire_page_lock(src_md);
   5445 	(void) pmap_clean_page(src_md, true);
   5446 	pmap_release_page_lock(src_md);
   5447 #endif
   5448 
   5449 	/*
   5450 	 * Map the pages into the page hook points, copy them, and purge
   5451 	 * the cache for the appropriate page. Invalidate the TLB
   5452 	 * as required.
   5453 	 */
   5454 	if (!src_okcolor) {
   5455 		const pt_entry_t nsrc_pte = L2_S_PROTO
   5456 		    | src
   5457 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   5458 		    | ((src_md->pvh_attrs & PVF_NC) ? 0 : pte_l2_s_cache_mode)
   5459 #else // defined(PMAP_CACHE_VIVT) || defined(ARM_MMU_EXTENDED)
   5460 		    | pte_l2_s_cache_mode
   5461 #endif
   5462 		    | L2_S_PROT(PTE_KERNEL, VM_PROT_READ);
   5463 		l2pte_set(src_ptep, nsrc_pte, 0);
   5464 		PTE_SYNC(src_ptep);
   5465 		cpu_tlb_flushD_SE(vsrcp);
   5466 		cpu_cpwait();
   5467 	}
   5468 	if (!dst_okcolor) {
   5469 		const pt_entry_t ndst_pte = L2_S_PROTO | dst |
   5470 		    L2_S_PROT(PTE_KERNEL, VM_PROT_WRITE) | pte_l2_s_cache_mode;
   5471 		l2pte_set(dst_ptep, ndst_pte, 0);
   5472 		PTE_SYNC(dst_ptep);
   5473 		cpu_tlb_flushD_SE(vdstp);
   5474 		cpu_cpwait();
   5475 #if defined(__HAVE_MM_MD_DIRECT_MAPPED_PHYS) && defined(PMAP_CACHE_VIPT)
   5476 		/*
   5477 		 * If we are direct-mapped and our color isn't ok, then before
   5478 		 * we bcopy to the new page invalidate its contents from the
   5479 		 * cache and reset its color to its natural color.
   5480 		 */
   5481 		cpu_dcache_inv_range(vdstp, PAGE_SIZE);
   5482 		dst_md->pvh_attrs &= ~arm_cache_prefer_mask;
   5483 		dst_md->pvh_attrs |= (dst & arm_cache_prefer_mask);
   5484 #endif
   5485 	}
   5486 	bcopy_page(vsrcp, vdstp);
   5487 #ifdef PMAP_CACHE_VIVT
   5488 	cpu_dcache_inv_range(vsrcp, PAGE_SIZE);
   5489 	cpu_dcache_wbinv_range(vdstp, PAGE_SIZE);
   5490 #endif
   5491 	/*
   5492 	 * Unmap the pages.
   5493 	 */
   5494 	if (!src_okcolor) {
   5495 		l2pte_reset(src_ptep);
   5496 		PTE_SYNC(src_ptep);
   5497 		cpu_tlb_flushD_SE(vsrcp);
   5498 		cpu_cpwait();
   5499 	}
   5500 	if (!dst_okcolor) {
   5501 		l2pte_reset(dst_ptep);
   5502 		PTE_SYNC(dst_ptep);
   5503 		cpu_tlb_flushD_SE(vdstp);
   5504 		cpu_cpwait();
   5505 	}
   5506 #ifdef PMAP_CACHE_VIPT
   5507 	/*
   5508 	 * Now that the destination page is in the cache, mark it as colored.
   5509 	 * If this was an exec page, discard it.
   5510 	 */
   5511 	pmap_acquire_page_lock(dst_md);
   5512 #ifndef ARM_MMU_EXTENDED
   5513 	if (arm_pcache.cache_type == CACHE_TYPE_PIPT) {
   5514 		dst_md->pvh_attrs &= ~arm_cache_prefer_mask;
   5515 		dst_md->pvh_attrs |= (dst & arm_cache_prefer_mask);
   5516 	}
   5517 	if (!pmap_is_page_colored_p(dst_md)) {
   5518 		PMAPCOUNT(vac_color_new);
   5519 		dst_md->pvh_attrs |= PVF_COLORED;
   5520 	}
   5521 	dst_md->pvh_attrs |= PVF_DIRTY;
   5522 #endif
   5523 	if (PV_IS_EXEC_P(dst_md->pvh_attrs)) {
   5524 		dst_md->pvh_attrs &= ~PVF_EXEC;
   5525 		PMAPCOUNT(exec_discarded_copy);
   5526 	}
   5527 	pmap_release_page_lock(dst_md);
   5528 #endif
   5529 }
   5530 #endif /* (ARM_MMU_GENERIC + ARM_MMU_SA1 + ARM_MMU_V6) != 0 */
   5531 
   5532 #if ARM_MMU_XSCALE == 1
   5533 void
   5534 pmap_copy_page_xscale(paddr_t src, paddr_t dst)
   5535 {
   5536 	struct vm_page *src_pg = PHYS_TO_VM_PAGE(src);
   5537 	struct vm_page_md *src_md = VM_PAGE_TO_MD(src_pg);
   5538 #ifdef DEBUG
   5539 	struct vm_page_md *dst_md = VM_PAGE_TO_MD(PHYS_TO_VM_PAGE(dst));
   5540 
   5541 	if (!SLIST_EMPTY(&dst_md->pvh_list))
   5542 		panic("pmap_copy_page: dst page has mappings");
   5543 #endif
   5544 
   5545 	KDASSERT((src & PGOFSET) == 0);
   5546 	KDASSERT((dst & PGOFSET) == 0);
   5547 
   5548 	/*
   5549 	 * Clean the source page.  Hold the source page's lock for
   5550 	 * the duration of the copy so that no other mappings can
   5551 	 * be created while we have a potentially aliased mapping.
   5552 	 */
   5553 #ifdef PMAP_CACHE_VIVT
   5554 	pmap_acquire_page_lock(src_md);
   5555 	(void) pmap_clean_page(src_md, true);
   5556 	pmap_release_page_lock(src_md);
   5557 #endif
   5558 
   5559 	/*
   5560 	 * Map the pages into the page hook points, copy them, and purge
   5561 	 * the cache for the appropriate page. Invalidate the TLB
   5562 	 * as required.
   5563 	 */
   5564 	const pt_entry_t nsrc_pte = L2_S_PROTO | src
   5565 	    | L2_S_PROT(PTE_KERNEL, VM_PROT_READ)
   5566 	    | L2_C | L2_XS_T_TEX(TEX_XSCALE_X);	/* mini-data */
   5567 	l2pte_set(csrc_pte, nsrc_pte, 0);
   5568 	PTE_SYNC(csrc_pte);
   5569 
   5570 	const pt_entry_t ndst_pte = L2_S_PROTO | dst
   5571 	    | L2_S_PROT(PTE_KERNEL, VM_PROT_WRITE)
   5572 	    | L2_C | L2_XS_T_TEX(TEX_XSCALE_X);	/* mini-data */
   5573 	l2pte_set(cdst_pte, ndst_pte, 0);
   5574 	PTE_SYNC(cdst_pte);
   5575 
   5576 	cpu_tlb_flushD_SE(csrcp);
   5577 	cpu_tlb_flushD_SE(cdstp);
   5578 	cpu_cpwait();
   5579 	bcopy_page(csrcp, cdstp);
   5580 	xscale_cache_clean_minidata();
   5581 	l2pte_reset(csrc_pte);
   5582 	l2pte_reset(cdst_pte);
   5583 	PTE_SYNC(csrc_pte);
   5584 	PTE_SYNC(cdst_pte);
   5585 }
   5586 #endif /* ARM_MMU_XSCALE == 1 */
   5587 
   5588 /*
   5589  * void pmap_virtual_space(vaddr_t *start, vaddr_t *end)
   5590  *
   5591  * Return the start and end addresses of the kernel's virtual space.
   5592  * These values are setup in pmap_bootstrap and are updated as pages
   5593  * are allocated.
   5594  */
   5595 void
   5596 pmap_virtual_space(vaddr_t *start, vaddr_t *end)
   5597 {
   5598 	*start = virtual_avail;
   5599 	*end = virtual_end;
   5600 }
   5601 
   5602 /*
   5603  * Helper function for pmap_grow_l2_bucket()
   5604  */
   5605 static inline int
   5606 pmap_grow_map(vaddr_t va, paddr_t *pap)
   5607 {
   5608 	paddr_t pa;
   5609 
   5610 	if (uvm.page_init_done == false) {
   5611 #ifdef PMAP_STEAL_MEMORY
   5612 		pv_addr_t pv;
   5613 		pmap_boot_pagealloc(PAGE_SIZE,
   5614 #ifdef PMAP_CACHE_VIPT
   5615 		    arm_cache_prefer_mask,
   5616 		    va & arm_cache_prefer_mask,
   5617 #else
   5618 		    0, 0,
   5619 #endif
   5620 		    &pv);
   5621 		pa = pv.pv_pa;
   5622 #else
   5623 		if (uvm_page_physget(&pa) == false)
   5624 			return (1);
   5625 #endif	/* PMAP_STEAL_MEMORY */
   5626 	} else {
   5627 		struct vm_page *pg;
   5628 		pg = uvm_pagealloc(NULL, 0, NULL, UVM_PGA_USERESERVE);
   5629 		if (pg == NULL)
   5630 			return (1);
   5631 		pa = VM_PAGE_TO_PHYS(pg);
   5632 		/*
   5633 		 * This new page must not have any mappings.  Enter it via
   5634 		 * pmap_kenter_pa and let that routine do the hard work.
   5635 		 */
   5636 		struct vm_page_md *md __diagused = VM_PAGE_TO_MD(pg);
   5637 		KASSERT(SLIST_EMPTY(&md->pvh_list));
   5638 		pmap_kenter_pa(va, pa,
   5639 		    VM_PROT_READ|VM_PROT_WRITE, PMAP_KMPAGE|PMAP_PTE);
   5640 	}
   5641 
   5642 	if (pap)
   5643 		*pap = pa;
   5644 
   5645 	PMAPCOUNT(pt_mappings);
   5646 #ifdef DEBUG
   5647 	struct l2_bucket * const l2b = pmap_get_l2_bucket(pmap_kernel(), va);
   5648 	KDASSERT(l2b != NULL);
   5649 
   5650 	pt_entry_t * const ptep = &l2b->l2b_kva[l2pte_index(va)];
   5651 	const pt_entry_t opte = *ptep;
   5652 	KDASSERT((opte & L2_S_CACHE_MASK) == pte_l2_s_cache_mode_pt);
   5653 #endif
   5654 	memset((void *)va, 0, PAGE_SIZE);
   5655 	return (0);
   5656 }
   5657 
   5658 /*
   5659  * This is the same as pmap_alloc_l2_bucket(), except that it is only
   5660  * used by pmap_growkernel().
   5661  */
   5662 static inline struct l2_bucket *
   5663 pmap_grow_l2_bucket(pmap_t pm, vaddr_t va)
   5664 {
   5665 	struct l2_dtable *l2;
   5666 	struct l2_bucket *l2b;
   5667 	u_short l1slot;
   5668 	vaddr_t nva;
   5669 
   5670 	l1slot = l1pte_index(va);
   5671 
   5672 	if ((l2 = pm->pm_l2[L2_IDX(l1slot)]) == NULL) {
   5673 		/*
   5674 		 * No mapping at this address, as there is
   5675 		 * no entry in the L1 table.
   5676 		 * Need to allocate a new l2_dtable.
   5677 		 */
   5678 		nva = pmap_kernel_l2dtable_kva;
   5679 		if ((nva & PGOFSET) == 0) {
   5680 			/*
   5681 			 * Need to allocate a backing page
   5682 			 */
   5683 			if (pmap_grow_map(nva, NULL))
   5684 				return (NULL);
   5685 		}
   5686 
   5687 		l2 = (struct l2_dtable *)nva;
   5688 		nva += sizeof(struct l2_dtable);
   5689 
   5690 		if ((nva & PGOFSET) < (pmap_kernel_l2dtable_kva & PGOFSET)) {
   5691 			/*
   5692 			 * The new l2_dtable straddles a page boundary.
   5693 			 * Map in another page to cover it.
   5694 			 */
   5695 			if (pmap_grow_map(nva, NULL))
   5696 				return (NULL);
   5697 		}
   5698 
   5699 		pmap_kernel_l2dtable_kva = nva;
   5700 
   5701 		/*
   5702 		 * Link it into the parent pmap
   5703 		 */
   5704 		pm->pm_l2[L2_IDX(l1slot)] = l2;
   5705 	}
   5706 
   5707 	l2b = &l2->l2_bucket[L2_BUCKET(l1slot)];
   5708 
   5709 	/*
   5710 	 * Fetch pointer to the L2 page table associated with the address.
   5711 	 */
   5712 	if (l2b->l2b_kva == NULL) {
   5713 		pt_entry_t *ptep;
   5714 
   5715 		/*
   5716 		 * No L2 page table has been allocated. Chances are, this
   5717 		 * is because we just allocated the l2_dtable, above.
   5718 		 */
   5719 		nva = pmap_kernel_l2ptp_kva;
   5720 		ptep = (pt_entry_t *)nva;
   5721 		if ((nva & PGOFSET) == 0) {
   5722 			/*
   5723 			 * Need to allocate a backing page
   5724 			 */
   5725 			if (pmap_grow_map(nva, &pmap_kernel_l2ptp_phys))
   5726 				return (NULL);
   5727 			PTE_SYNC_RANGE(ptep, PAGE_SIZE / sizeof(pt_entry_t));
   5728 		}
   5729 
   5730 		l2->l2_occupancy++;
   5731 		l2b->l2b_kva = ptep;
   5732 		l2b->l2b_l1slot = l1slot;
   5733 		l2b->l2b_pa = pmap_kernel_l2ptp_phys;
   5734 
   5735 		pmap_kernel_l2ptp_kva += L2_TABLE_SIZE_REAL;
   5736 		pmap_kernel_l2ptp_phys += L2_TABLE_SIZE_REAL;
   5737 	}
   5738 
   5739 	return (l2b);
   5740 }
   5741 
   5742 vaddr_t
   5743 pmap_growkernel(vaddr_t maxkvaddr)
   5744 {
   5745 	pmap_t kpm = pmap_kernel();
   5746 #ifndef ARM_MMU_EXTENDED
   5747 	struct l1_ttable *l1;
   5748 #endif
   5749 	int s;
   5750 
   5751 	if (maxkvaddr <= pmap_curmaxkvaddr)
   5752 		goto out;		/* we are OK */
   5753 
   5754 	NPDEBUG(PDB_GROWKERN,
   5755 	    printf("pmap_growkernel: growing kernel from 0x%lx to 0x%lx\n",
   5756 	    pmap_curmaxkvaddr, maxkvaddr));
   5757 
   5758 	KDASSERT(maxkvaddr <= virtual_end);
   5759 
   5760 	/*
   5761 	 * whoops!   we need to add kernel PTPs
   5762 	 */
   5763 
   5764 	s = splhigh();	/* to be safe */
   5765 	mutex_enter(kpm->pm_lock);
   5766 
   5767 	/* Map 1MB at a time */
   5768 	size_t l1slot = l1pte_index(pmap_curmaxkvaddr);
   5769 #ifdef ARM_MMU_EXTENDED
   5770 	pd_entry_t * const spdep = &kpm->pm_l1[l1slot];
   5771 	pd_entry_t *pdep = spdep;
   5772 #endif
   5773 	for (;pmap_curmaxkvaddr < maxkvaddr; pmap_curmaxkvaddr += L1_S_SIZE,
   5774 #ifdef ARM_MMU_EXTENDED
   5775 	     pdep++,
   5776 #endif
   5777 	     l1slot++) {
   5778 		struct l2_bucket *l2b =
   5779 		    pmap_grow_l2_bucket(kpm, pmap_curmaxkvaddr);
   5780 		KASSERT(l2b != NULL);
   5781 
   5782 		const pd_entry_t npde = L1_C_PROTO | l2b->l2b_pa
   5783 		    | L1_C_DOM(PMAP_DOMAIN_KERNEL);
   5784 #ifdef ARM_MMU_EXTENDED
   5785 		l1pte_setone(pdep, npde);
   5786 #else
   5787 		/* Distribute new L1 entry to all other L1s */
   5788 		SLIST_FOREACH(l1, &l1_list, l1_link) {
   5789 			pd_entry_t * const pdep = &l1->l1_kva[l1slot];
   5790 			l1pte_setone(pdep, npde);
   5791 			PDE_SYNC(pdep);
   5792 		}
   5793 #endif
   5794 	}
   5795 #ifdef ARM_MMU_EXTENDED
   5796 	PDE_SYNC_RANGE(spdep, pdep - spdep);
   5797 #endif
   5798 
   5799 #ifdef PMAP_CACHE_VIVT
   5800 	/*
   5801 	 * flush out the cache, expensive but growkernel will happen so
   5802 	 * rarely
   5803 	 */
   5804 	cpu_dcache_wbinv_all();
   5805 	cpu_tlb_flushD();
   5806 	cpu_cpwait();
   5807 #endif
   5808 
   5809 	mutex_exit(kpm->pm_lock);
   5810 	splx(s);
   5811 
   5812 out:
   5813 	return (pmap_curmaxkvaddr);
   5814 }
   5815 
   5816 /************************ Utility routines ****************************/
   5817 
   5818 #ifndef ARM_HAS_VBAR
   5819 /*
   5820  * vector_page_setprot:
   5821  *
   5822  *	Manipulate the protection of the vector page.
   5823  */
   5824 void
   5825 vector_page_setprot(int prot)
   5826 {
   5827 	struct l2_bucket *l2b;
   5828 	pt_entry_t *ptep;
   5829 
   5830 #if defined(CPU_ARMV7) || defined(CPU_ARM11)
   5831 	/*
   5832 	 * If we are using VBAR to use the vectors in the kernel, then it's
   5833 	 * already mapped in the kernel text so no need to anything here.
   5834 	 */
   5835 	if (vector_page != ARM_VECTORS_LOW && vector_page != ARM_VECTORS_HIGH) {
   5836 		KASSERT((armreg_pfr1_read() & ARM_PFR1_SEC_MASK) != 0);
   5837 		return;
   5838 	}
   5839 #endif
   5840 
   5841 	l2b = pmap_get_l2_bucket(pmap_kernel(), vector_page);
   5842 	KASSERT(l2b != NULL);
   5843 
   5844 	ptep = &l2b->l2b_kva[l2pte_index(vector_page)];
   5845 
   5846 	const pt_entry_t opte = *ptep;
   5847 #ifdef ARM_MMU_EXTENDED
   5848 	const pt_entry_t npte = (opte & ~(L2_S_PROT_MASK|L2_XS_XN))
   5849 	    | L2_S_PROT(PTE_KERNEL, prot);
   5850 #else
   5851 	const pt_entry_t npte = (opte & ~L2_S_PROT_MASK)
   5852 	    | L2_S_PROT(PTE_KERNEL, prot);
   5853 #endif
   5854 	l2pte_set(ptep, npte, opte);
   5855 	PTE_SYNC(ptep);
   5856 	cpu_tlb_flushD_SE(vector_page);
   5857 	cpu_cpwait();
   5858 }
   5859 #endif
   5860 
   5861 /*
   5862  * Fetch pointers to the PDE/PTE for the given pmap/VA pair.
   5863  * Returns true if the mapping exists, else false.
   5864  *
   5865  * NOTE: This function is only used by a couple of arm-specific modules.
   5866  * It is not safe to take any pmap locks here, since we could be right
   5867  * in the middle of debugging the pmap anyway...
   5868  *
   5869  * It is possible for this routine to return false even though a valid
   5870  * mapping does exist. This is because we don't lock, so the metadata
   5871  * state may be inconsistent.
   5872  *
   5873  * NOTE: We can return a NULL *ptp in the case where the L1 pde is
   5874  * a "section" mapping.
   5875  */
   5876 bool
   5877 pmap_get_pde_pte(pmap_t pm, vaddr_t va, pd_entry_t **pdp, pt_entry_t **ptp)
   5878 {
   5879 	struct l2_dtable *l2;
   5880 	pd_entry_t *pdep, pde;
   5881 	pt_entry_t *ptep;
   5882 	u_short l1slot;
   5883 
   5884 	if (pm->pm_l1 == NULL)
   5885 		return false;
   5886 
   5887 	l1slot = l1pte_index(va);
   5888 	*pdp = pdep = pmap_l1_kva(pm) + l1slot;
   5889 	pde = *pdep;
   5890 
   5891 	if (l1pte_section_p(pde)) {
   5892 		*ptp = NULL;
   5893 		return true;
   5894 	}
   5895 
   5896 	l2 = pm->pm_l2[L2_IDX(l1slot)];
   5897 	if (l2 == NULL ||
   5898 	    (ptep = l2->l2_bucket[L2_BUCKET(l1slot)].l2b_kva) == NULL) {
   5899 		return false;
   5900 	}
   5901 
   5902 	*ptp = &ptep[l2pte_index(va)];
   5903 	return true;
   5904 }
   5905 
   5906 bool
   5907 pmap_get_pde(pmap_t pm, vaddr_t va, pd_entry_t **pdp)
   5908 {
   5909 
   5910 	if (pm->pm_l1 == NULL)
   5911 		return false;
   5912 
   5913 	*pdp = pmap_l1_kva(pm) + l1pte_index(va);
   5914 
   5915 	return true;
   5916 }
   5917 
   5918 /************************ Bootstrapping routines ****************************/
   5919 
   5920 #ifndef ARM_MMU_EXTENDED
   5921 static void
   5922 pmap_init_l1(struct l1_ttable *l1, pd_entry_t *l1pt)
   5923 {
   5924 	int i;
   5925 
   5926 	l1->l1_kva = l1pt;
   5927 	l1->l1_domain_use_count = 0;
   5928 	l1->l1_domain_first = 0;
   5929 
   5930 	for (i = 0; i < PMAP_DOMAINS; i++)
   5931 		l1->l1_domain_free[i] = i + 1;
   5932 
   5933 	/*
   5934 	 * Copy the kernel's L1 entries to each new L1.
   5935 	 */
   5936 	if (pmap_initialized)
   5937 		memcpy(l1pt, pmap_l1_kva(pmap_kernel()), L1_TABLE_SIZE);
   5938 
   5939 	if (pmap_extract(pmap_kernel(), (vaddr_t)l1pt,
   5940 	    &l1->l1_physaddr) == false)
   5941 		panic("pmap_init_l1: can't get PA of L1 at %p", l1pt);
   5942 
   5943 	SLIST_INSERT_HEAD(&l1_list, l1, l1_link);
   5944 	TAILQ_INSERT_TAIL(&l1_lru_list, l1, l1_lru);
   5945 }
   5946 #endif /* !ARM_MMU_EXTENDED */
   5947 
   5948 /*
   5949  * pmap_bootstrap() is called from the board-specific initarm() routine
   5950  * once the kernel L1/L2 descriptors tables have been set up.
   5951  *
   5952  * This is a somewhat convoluted process since pmap bootstrap is, effectively,
   5953  * spread over a number of disparate files/functions.
   5954  *
   5955  * We are passed the following parameters
   5956  *  - kernel_l1pt
   5957  *    This is a pointer to the base of the kernel's L1 translation table.
   5958  *  - vstart
   5959  *    1MB-aligned start of managed kernel virtual memory.
   5960  *  - vend
   5961  *    1MB-aligned end of managed kernel virtual memory.
   5962  *
   5963  * We use the first parameter to build the metadata (struct l1_ttable and
   5964  * struct l2_dtable) necessary to track kernel mappings.
   5965  */
   5966 #define	PMAP_STATIC_L2_SIZE 16
   5967 void
   5968 pmap_bootstrap(vaddr_t vstart, vaddr_t vend)
   5969 {
   5970 	static struct l2_dtable static_l2[PMAP_STATIC_L2_SIZE];
   5971 #ifndef ARM_MMU_EXTENDED
   5972 	static struct l1_ttable static_l1;
   5973 	struct l1_ttable *l1 = &static_l1;
   5974 #endif
   5975 	struct l2_dtable *l2;
   5976 	struct l2_bucket *l2b;
   5977 	pd_entry_t *l1pt = (pd_entry_t *) kernel_l1pt.pv_va;
   5978 	pmap_t pm = pmap_kernel();
   5979 	pt_entry_t *ptep;
   5980 	paddr_t pa;
   5981 	vsize_t size;
   5982 	int nptes, l2idx, l2next = 0;
   5983 
   5984 #ifdef ARM_MMU_EXTENDED
   5985 	KASSERT(pte_l1_s_cache_mode == pte_l1_s_cache_mode_pt);
   5986 	KASSERT(pte_l2_s_cache_mode == pte_l2_s_cache_mode_pt);
   5987 #endif
   5988 
   5989 #ifdef VERBOSE_INIT_ARM
   5990 	printf("kpm ");
   5991 #endif
   5992 	/*
   5993 	 * Initialise the kernel pmap object
   5994 	 */
   5995 	curcpu()->ci_pmap_cur = pm;
   5996 #ifdef ARM_MMU_EXTENDED
   5997 	pm->pm_l1 = l1pt;
   5998 	pm->pm_l1_pa = kernel_l1pt.pv_pa;
   5999 #ifdef VERBOSE_INIT_ARM
   6000 	printf("tlb0 ");
   6001 #endif
   6002 	pmap_tlb_info_init(&pmap_tlb0_info);
   6003 #ifdef MULTIPROCESSOR
   6004 #ifdef VERBOSE_INIT_ARM
   6005 	printf("kcpusets ");
   6006 #endif
   6007 	pm->pm_onproc = kcpuset_running;
   6008 	pm->pm_active = kcpuset_running;
   6009 #endif
   6010 #else
   6011 	pm->pm_l1 = l1;
   6012 #endif
   6013 
   6014 #ifdef VERBOSE_INIT_ARM
   6015 	printf("locks ");
   6016 #endif
   6017 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   6018 	if (arm_cache_prefer_mask != 0) {
   6019 		mutex_init(&pmap_lock, MUTEX_DEFAULT, IPL_VM);
   6020 	} else {
   6021 #endif
   6022 		mutex_init(&pmap_lock, MUTEX_DEFAULT, IPL_NONE);
   6023 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   6024 	}
   6025 #endif
   6026 	mutex_init(&pm->pm_obj_lock, MUTEX_DEFAULT, IPL_NONE);
   6027 	uvm_obj_init(&pm->pm_obj, NULL, false, 1);
   6028 	uvm_obj_setlock(&pm->pm_obj, &pm->pm_obj_lock);
   6029 
   6030 #ifdef VERBOSE_INIT_ARM
   6031 	printf("l1pt ");
   6032 #endif
   6033 	/*
   6034 	 * Scan the L1 translation table created by initarm() and create
   6035 	 * the required metadata for all valid mappings found in it.
   6036 	 */
   6037 	for (size_t l1slot = 0;
   6038 	     l1slot < L1_TABLE_SIZE / sizeof(pd_entry_t);
   6039 	     l1slot++) {
   6040 		pd_entry_t pde = l1pt[l1slot];
   6041 
   6042 		/*
   6043 		 * We're only interested in Coarse mappings.
   6044 		 * pmap_extract() can deal with section mappings without
   6045 		 * recourse to checking L2 metadata.
   6046 		 */
   6047 		if ((pde & L1_TYPE_MASK) != L1_TYPE_C)
   6048 			continue;
   6049 
   6050 		/*
   6051 		 * Lookup the KVA of this L2 descriptor table
   6052 		 */
   6053 		pa = l1pte_pa(pde);
   6054 		ptep = (pt_entry_t *)kernel_pt_lookup(pa);
   6055 		if (ptep == NULL) {
   6056 			panic("pmap_bootstrap: No L2 for va 0x%x, pa 0x%lx",
   6057 			    (u_int)l1slot << L1_S_SHIFT, pa);
   6058 		}
   6059 
   6060 		/*
   6061 		 * Fetch the associated L2 metadata structure.
   6062 		 * Allocate a new one if necessary.
   6063 		 */
   6064 		if ((l2 = pm->pm_l2[L2_IDX(l1slot)]) == NULL) {
   6065 			if (l2next == PMAP_STATIC_L2_SIZE)
   6066 				panic("pmap_bootstrap: out of static L2s");
   6067 			pm->pm_l2[L2_IDX(l1slot)] = l2 = &static_l2[l2next++];
   6068 		}
   6069 
   6070 		/*
   6071 		 * One more L1 slot tracked...
   6072 		 */
   6073 		l2->l2_occupancy++;
   6074 
   6075 		/*
   6076 		 * Fill in the details of the L2 descriptor in the
   6077 		 * appropriate bucket.
   6078 		 */
   6079 		l2b = &l2->l2_bucket[L2_BUCKET(l1slot)];
   6080 		l2b->l2b_kva = ptep;
   6081 		l2b->l2b_pa = pa;
   6082 		l2b->l2b_l1slot = l1slot;
   6083 
   6084 		/*
   6085 		 * Establish an initial occupancy count for this descriptor
   6086 		 */
   6087 		for (l2idx = 0;
   6088 		    l2idx < (L2_TABLE_SIZE_REAL / sizeof(pt_entry_t));
   6089 		    l2idx++) {
   6090 			if ((ptep[l2idx] & L2_TYPE_MASK) != L2_TYPE_INV) {
   6091 				l2b->l2b_occupancy++;
   6092 			}
   6093 		}
   6094 
   6095 		/*
   6096 		 * Make sure the descriptor itself has the correct cache mode.
   6097 		 * If not, fix it, but whine about the problem. Port-meisters
   6098 		 * should consider this a clue to fix up their initarm()
   6099 		 * function. :)
   6100 		 */
   6101 		if (pmap_set_pt_cache_mode(l1pt, (vaddr_t)ptep, 1)) {
   6102 			printf("pmap_bootstrap: WARNING! wrong cache mode for "
   6103 			    "L2 pte @ %p\n", ptep);
   6104 		}
   6105 	}
   6106 
   6107 #ifdef VERBOSE_INIT_ARM
   6108 	printf("cache(l1pt) ");
   6109 #endif
   6110 	/*
   6111 	 * Ensure the primary (kernel) L1 has the correct cache mode for
   6112 	 * a page table. Bitch if it is not correctly set.
   6113 	 */
   6114 	if (pmap_set_pt_cache_mode(l1pt, kernel_l1pt.pv_va,
   6115 		    L1_TABLE_SIZE / L2_S_SIZE)) {
   6116 		printf("pmap_bootstrap: WARNING! wrong cache mode for "
   6117 		    "primary L1 @ 0x%lx\n", kernel_l1pt.pv_va);
   6118 	}
   6119 
   6120 #ifdef PMAP_CACHE_VIVT
   6121 	cpu_dcache_wbinv_all();
   6122 	cpu_tlb_flushID();
   6123 	cpu_cpwait();
   6124 #endif
   6125 
   6126 	/*
   6127 	 * now we allocate the "special" VAs which are used for tmp mappings
   6128 	 * by the pmap (and other modules).  we allocate the VAs by advancing
   6129 	 * virtual_avail (note that there are no pages mapped at these VAs).
   6130 	 *
   6131 	 * Managed KVM space start from wherever initarm() tells us.
   6132 	 */
   6133 	virtual_avail = vstart;
   6134 	virtual_end = vend;
   6135 
   6136 #ifdef VERBOSE_INIT_ARM
   6137 	printf("specials ");
   6138 #endif
   6139 #ifdef PMAP_CACHE_VIPT
   6140 	/*
   6141 	 * If we have a VIPT cache, we need one page/pte per possible alias
   6142 	 * page so we won't violate cache aliasing rules.
   6143 	 */
   6144 	virtual_avail = (virtual_avail + arm_cache_prefer_mask) & ~arm_cache_prefer_mask;
   6145 	nptes = (arm_cache_prefer_mask >> L2_S_SHIFT) + 1;
   6146 	if (arm_pcache.icache_type != CACHE_TYPE_PIPT
   6147 	    && arm_pcache.icache_way_size > nptes * L2_S_SIZE) {
   6148 		nptes = arm_pcache.icache_way_size >> L2_S_SHIFT;
   6149 	}
   6150 #else
   6151 	nptes = PAGE_SIZE / L2_S_SIZE;
   6152 #endif
   6153 #ifdef MULTIPROCESSOR
   6154 	cnptes = nptes;
   6155 	nptes *= arm_cpu_max;
   6156 #endif
   6157 	pmap_alloc_specials(&virtual_avail, nptes, &csrcp, &csrc_pte);
   6158 	pmap_set_pt_cache_mode(l1pt, (vaddr_t)csrc_pte, nptes);
   6159 	pmap_alloc_specials(&virtual_avail, nptes, &cdstp, &cdst_pte);
   6160 	pmap_set_pt_cache_mode(l1pt, (vaddr_t)cdst_pte, nptes);
   6161 	pmap_alloc_specials(&virtual_avail, nptes, &memhook, NULL);
   6162 	if (msgbufaddr == NULL) {
   6163 		pmap_alloc_specials(&virtual_avail,
   6164 		    round_page(MSGBUFSIZE) / PAGE_SIZE,
   6165 		    (void *)&msgbufaddr, NULL);
   6166 	}
   6167 
   6168 	/*
   6169 	 * Allocate a range of kernel virtual address space to be used
   6170 	 * for L2 descriptor tables and metadata allocation in
   6171 	 * pmap_growkernel().
   6172 	 */
   6173 	size = ((virtual_end - pmap_curmaxkvaddr) + L1_S_OFFSET) / L1_S_SIZE;
   6174 	pmap_alloc_specials(&virtual_avail,
   6175 	    round_page(size * L2_TABLE_SIZE_REAL) / PAGE_SIZE,
   6176 	    &pmap_kernel_l2ptp_kva, NULL);
   6177 
   6178 	size = (size + (L2_BUCKET_SIZE - 1)) / L2_BUCKET_SIZE;
   6179 	pmap_alloc_specials(&virtual_avail,
   6180 	    round_page(size * sizeof(struct l2_dtable)) / PAGE_SIZE,
   6181 	    &pmap_kernel_l2dtable_kva, NULL);
   6182 
   6183 #ifndef ARM_MMU_EXTENDED
   6184 	/*
   6185 	 * init the static-global locks and global pmap list.
   6186 	 */
   6187 	mutex_init(&l1_lru_lock, MUTEX_DEFAULT, IPL_VM);
   6188 
   6189 	/*
   6190 	 * We can now initialise the first L1's metadata.
   6191 	 */
   6192 	SLIST_INIT(&l1_list);
   6193 	TAILQ_INIT(&l1_lru_list);
   6194 	pmap_init_l1(l1, l1pt);
   6195 #endif /* ARM_MMU_EXTENDED */
   6196 
   6197 #ifndef ARM_HAS_VBAR
   6198 	/* Set up vector page L1 details, if necessary */
   6199 	if (vector_page < KERNEL_BASE) {
   6200 		pm->pm_pl1vec = pmap_l1_kva(pm) + l1pte_index(vector_page);
   6201 		l2b = pmap_get_l2_bucket(pm, vector_page);
   6202 		KDASSERT(l2b != NULL);
   6203 		pm->pm_l1vec = l2b->l2b_pa | L1_C_PROTO |
   6204 		    L1_C_DOM(pmap_domain(pm));
   6205 	} else
   6206 		pm->pm_pl1vec = NULL;
   6207 #endif
   6208 
   6209 #ifdef VERBOSE_INIT_ARM
   6210 	printf("pools ");
   6211 #endif
   6212 	/*
   6213 	 * Initialize the pmap cache
   6214 	 */
   6215 	pool_cache_bootstrap(&pmap_cache, sizeof(struct pmap), 0, 0, 0,
   6216 	    "pmappl", NULL, IPL_NONE, pmap_pmap_ctor, NULL, NULL);
   6217 	LIST_INIT(&pmap_pmaps);
   6218 	LIST_INSERT_HEAD(&pmap_pmaps, pm, pm_list);
   6219 
   6220 	/*
   6221 	 * Initialize the pv pool.
   6222 	 */
   6223 	pool_init(&pmap_pv_pool, sizeof(struct pv_entry), 0, 0, 0, "pvepl",
   6224 	    &pmap_bootstrap_pv_allocator, IPL_NONE);
   6225 
   6226 	/*
   6227 	 * Initialize the L2 dtable pool and cache.
   6228 	 */
   6229 	pool_cache_bootstrap(&pmap_l2dtable_cache, sizeof(struct l2_dtable), 0,
   6230 	    0, 0, "l2dtblpl", NULL, IPL_NONE, pmap_l2dtable_ctor, NULL, NULL);
   6231 
   6232 	/*
   6233 	 * Initialise the L2 descriptor table pool and cache
   6234 	 */
   6235 	pool_cache_bootstrap(&pmap_l2ptp_cache, L2_TABLE_SIZE_REAL, 0,
   6236 	    L2_TABLE_SIZE_REAL, 0, "l2ptppl", NULL, IPL_NONE,
   6237 	    pmap_l2ptp_ctor, NULL, NULL);
   6238 
   6239 	mutex_init(&memlock, MUTEX_DEFAULT, IPL_NONE);
   6240 
   6241 	cpu_dcache_wbinv_all();
   6242 }
   6243 
   6244 static bool
   6245 pmap_set_pt_cache_mode(pd_entry_t *kl1, vaddr_t va, size_t nptes)
   6246 {
   6247 #ifdef ARM_MMU_EXTENDED
   6248 	return false;
   6249 #else
   6250 	if (pte_l1_s_cache_mode == pte_l1_s_cache_mode_pt
   6251 	    && pte_l2_s_cache_mode == pte_l2_s_cache_mode_pt)
   6252 		return false;
   6253 
   6254 	const vaddr_t eva = va + nptes * PAGE_SIZE;
   6255 	int rv = 0;
   6256 
   6257 	while (va < eva) {
   6258 		/*
   6259 		 * Make sure the descriptor itself has the correct cache mode
   6260 		 */
   6261 		pd_entry_t * const pdep = &kl1[l1pte_index(va)];
   6262 		pd_entry_t pde = *pdep;
   6263 
   6264 		if (l1pte_section_p(pde)) {
   6265 			__CTASSERT((L1_S_CACHE_MASK & L1_S_V6_SUPER) == 0);
   6266 			if ((pde & L1_S_CACHE_MASK) != pte_l1_s_cache_mode_pt) {
   6267 				*pdep = (pde & ~L1_S_CACHE_MASK) |
   6268 				    pte_l1_s_cache_mode_pt;
   6269 				PDE_SYNC(pdep);
   6270 				cpu_dcache_wbinv_range((vaddr_t)pdep,
   6271 				    sizeof(*pdep));
   6272 				rv = 1;
   6273 			}
   6274 			return rv;
   6275 		}
   6276 		vaddr_t pa = l1pte_pa(pde);
   6277 		pt_entry_t *ptep = (pt_entry_t *)kernel_pt_lookup(pa);
   6278 		if (ptep == NULL)
   6279 			panic("pmap_bootstrap: No PTP for va %#lx\n", va);
   6280 
   6281 		ptep += l2pte_index(va);
   6282 		const pt_entry_t opte = *ptep;
   6283 		if ((opte & L2_S_CACHE_MASK) != pte_l2_s_cache_mode_pt) {
   6284 			const pt_entry_t npte = (opte & ~L2_S_CACHE_MASK)
   6285 			    | pte_l2_s_cache_mode_pt;
   6286 			l2pte_set(ptep, npte, opte);
   6287 			PTE_SYNC(ptep);
   6288 			cpu_dcache_wbinv_range((vaddr_t)ptep, sizeof(*ptep));
   6289 			rv = 1;
   6290 		}
   6291 		va += PAGE_SIZE;
   6292 	}
   6293 
   6294 	return (rv);
   6295 #endif
   6296 }
   6297 
   6298 static void
   6299 pmap_alloc_specials(vaddr_t *availp, int pages, vaddr_t *vap, pt_entry_t **ptep)
   6300 {
   6301 	vaddr_t va = *availp;
   6302 	struct l2_bucket *l2b;
   6303 
   6304 	if (ptep) {
   6305 		l2b = pmap_get_l2_bucket(pmap_kernel(), va);
   6306 		if (l2b == NULL)
   6307 			panic("pmap_alloc_specials: no l2b for 0x%lx", va);
   6308 
   6309 		if (ptep)
   6310 			*ptep = &l2b->l2b_kva[l2pte_index(va)];
   6311 	}
   6312 
   6313 	*vap = va;
   6314 	*availp = va + (PAGE_SIZE * pages);
   6315 }
   6316 
   6317 void
   6318 pmap_init(void)
   6319 {
   6320 
   6321 	/*
   6322 	 * Set the available memory vars - These do not map to real memory
   6323 	 * addresses and cannot as the physical memory is fragmented.
   6324 	 * They are used by ps for %mem calculations.
   6325 	 * One could argue whether this should be the entire memory or just
   6326 	 * the memory that is useable in a user process.
   6327 	 */
   6328 	avail_start = ptoa(VM_PHYSMEM_PTR(0)->start);
   6329 	avail_end = ptoa(VM_PHYSMEM_PTR(vm_nphysseg - 1)->end);
   6330 
   6331 	/*
   6332 	 * Now we need to free enough pv_entry structures to allow us to get
   6333 	 * the kmem_map/kmem_object allocated and inited (done after this
   6334 	 * function is finished).  to do this we allocate one bootstrap page out
   6335 	 * of kernel_map and use it to provide an initial pool of pv_entry
   6336 	 * structures.   we never free this page.
   6337 	 */
   6338 	pool_setlowat(&pmap_pv_pool, (PAGE_SIZE / sizeof(struct pv_entry)) * 2);
   6339 
   6340 #ifdef ARM_MMU_EXTENDED
   6341 	pmap_tlb_info_evcnt_attach(&pmap_tlb0_info);
   6342 #endif
   6343 
   6344 	pmap_initialized = true;
   6345 }
   6346 
   6347 static vaddr_t last_bootstrap_page = 0;
   6348 static void *free_bootstrap_pages = NULL;
   6349 
   6350 static void *
   6351 pmap_bootstrap_pv_page_alloc(struct pool *pp, int flags)
   6352 {
   6353 	extern void *pool_page_alloc(struct pool *, int);
   6354 	vaddr_t new_page;
   6355 	void *rv;
   6356 
   6357 	if (pmap_initialized)
   6358 		return (pool_page_alloc(pp, flags));
   6359 
   6360 	if (free_bootstrap_pages) {
   6361 		rv = free_bootstrap_pages;
   6362 		free_bootstrap_pages = *((void **)rv);
   6363 		return (rv);
   6364 	}
   6365 
   6366 	KASSERT(kernel_map != NULL);
   6367 	new_page = uvm_km_alloc(kernel_map, PAGE_SIZE, 0,
   6368 	    UVM_KMF_WIRED | ((flags & PR_WAITOK) ? 0 : UVM_KMF_NOWAIT));
   6369 
   6370 	KASSERT(new_page > last_bootstrap_page);
   6371 	last_bootstrap_page = new_page;
   6372 	return ((void *)new_page);
   6373 }
   6374 
   6375 static void
   6376 pmap_bootstrap_pv_page_free(struct pool *pp, void *v)
   6377 {
   6378 	extern void pool_page_free(struct pool *, void *);
   6379 
   6380 	if ((vaddr_t)v <= last_bootstrap_page) {
   6381 		*((void **)v) = free_bootstrap_pages;
   6382 		free_bootstrap_pages = v;
   6383 		return;
   6384 	}
   6385 
   6386 	if (pmap_initialized) {
   6387 		pool_page_free(pp, v);
   6388 		return;
   6389 	}
   6390 }
   6391 
   6392 /*
   6393  * pmap_postinit()
   6394  *
   6395  * This routine is called after the vm and kmem subsystems have been
   6396  * initialised. This allows the pmap code to perform any initialisation
   6397  * that can only be done one the memory allocation is in place.
   6398  */
   6399 void
   6400 pmap_postinit(void)
   6401 {
   6402 #ifndef ARM_MMU_EXTENDED
   6403 	extern paddr_t physical_start, physical_end;
   6404 	struct l1_ttable *l1;
   6405 	struct pglist plist;
   6406 	struct vm_page *m;
   6407 	pd_entry_t *pdep;
   6408 	vaddr_t va, eva;
   6409 	u_int loop, needed;
   6410 	int error;
   6411 #endif
   6412 
   6413 	pool_cache_setlowat(&pmap_l2ptp_cache, (PAGE_SIZE / L2_TABLE_SIZE_REAL) * 4);
   6414 	pool_cache_setlowat(&pmap_l2dtable_cache,
   6415 	    (PAGE_SIZE / sizeof(struct l2_dtable)) * 2);
   6416 
   6417 #ifndef ARM_MMU_EXTENDED
   6418 	needed = (maxproc / PMAP_DOMAINS) + ((maxproc % PMAP_DOMAINS) ? 1 : 0);
   6419 	needed -= 1;
   6420 
   6421 	l1 = kmem_alloc(sizeof(*l1) * needed, KM_SLEEP);
   6422 
   6423 	for (loop = 0; loop < needed; loop++, l1++) {
   6424 		/* Allocate a L1 page table */
   6425 		va = uvm_km_alloc(kernel_map, L1_TABLE_SIZE, 0, UVM_KMF_VAONLY);
   6426 		if (va == 0)
   6427 			panic("Cannot allocate L1 KVM");
   6428 
   6429 		error = uvm_pglistalloc(L1_TABLE_SIZE, physical_start,
   6430 		    physical_end, L1_TABLE_SIZE, 0, &plist, 1, 1);
   6431 		if (error)
   6432 			panic("Cannot allocate L1 physical pages");
   6433 
   6434 		m = TAILQ_FIRST(&plist);
   6435 		eva = va + L1_TABLE_SIZE;
   6436 		pdep = (pd_entry_t *)va;
   6437 
   6438 		while (m && va < eva) {
   6439 			paddr_t pa = VM_PAGE_TO_PHYS(m);
   6440 
   6441 			pmap_kenter_pa(va, pa,
   6442 			    VM_PROT_READ|VM_PROT_WRITE, PMAP_KMPAGE|PMAP_PTE);
   6443 
   6444 			va += PAGE_SIZE;
   6445 			m = TAILQ_NEXT(m, pageq.queue);
   6446 		}
   6447 
   6448 #ifdef DIAGNOSTIC
   6449 		if (m)
   6450 			panic("pmap_alloc_l1pt: pglist not empty");
   6451 #endif	/* DIAGNOSTIC */
   6452 
   6453 		pmap_init_l1(l1, pdep);
   6454 	}
   6455 
   6456 #ifdef DEBUG
   6457 	printf("pmap_postinit: Allocated %d static L1 descriptor tables\n",
   6458 	    needed);
   6459 #endif
   6460 #endif /* !ARM_MMU_EXTENDED */
   6461 }
   6462 
   6463 /*
   6464  * Note that the following routines are used by board-specific initialisation
   6465  * code to configure the initial kernel page tables.
   6466  *
   6467  * If ARM32_NEW_VM_LAYOUT is *not* defined, they operate on the assumption that
   6468  * L2 page-table pages are 4KB in size and use 4 L1 slots. This mimics the
   6469  * behaviour of the old pmap, and provides an easy migration path for
   6470  * initial bring-up of the new pmap on existing ports. Fortunately,
   6471  * pmap_bootstrap() compensates for this hackery. This is only a stop-gap and
   6472  * will be deprecated.
   6473  *
   6474  * If ARM32_NEW_VM_LAYOUT *is* defined, these functions deal with 1KB L2 page
   6475  * tables.
   6476  */
   6477 
   6478 /*
   6479  * This list exists for the benefit of pmap_map_chunk().  It keeps track
   6480  * of the kernel L2 tables during bootstrap, so that pmap_map_chunk() can
   6481  * find them as necessary.
   6482  *
   6483  * Note that the data on this list MUST remain valid after initarm() returns,
   6484  * as pmap_bootstrap() uses it to contruct L2 table metadata.
   6485  */
   6486 SLIST_HEAD(, pv_addr) kernel_pt_list = SLIST_HEAD_INITIALIZER(kernel_pt_list);
   6487 
   6488 static vaddr_t
   6489 kernel_pt_lookup(paddr_t pa)
   6490 {
   6491 	pv_addr_t *pv;
   6492 
   6493 	SLIST_FOREACH(pv, &kernel_pt_list, pv_list) {
   6494 		if (pv->pv_pa == (pa & ~PGOFSET))
   6495 			return (pv->pv_va | (pa & PGOFSET));
   6496 	}
   6497 	return (0);
   6498 }
   6499 
   6500 /*
   6501  * pmap_map_section:
   6502  *
   6503  *	Create a single section mapping.
   6504  */
   6505 void
   6506 pmap_map_section(vaddr_t l1pt, vaddr_t va, paddr_t pa, int prot, int cache)
   6507 {
   6508 	pd_entry_t * const pdep = (pd_entry_t *) l1pt;
   6509 	const size_t l1slot = l1pte_index(va);
   6510 	pd_entry_t fl;
   6511 
   6512 	KASSERT(((va | pa) & L1_S_OFFSET) == 0);
   6513 
   6514 	switch (cache) {
   6515 	case PTE_NOCACHE:
   6516 	default:
   6517 		fl = 0;
   6518 		break;
   6519 
   6520 	case PTE_CACHE:
   6521 		fl = pte_l1_s_cache_mode;
   6522 		break;
   6523 
   6524 	case PTE_PAGETABLE:
   6525 		fl = pte_l1_s_cache_mode_pt;
   6526 		break;
   6527 	}
   6528 
   6529 	const pd_entry_t npde = L1_S_PROTO | pa |
   6530 	    L1_S_PROT(PTE_KERNEL, prot) | fl | L1_S_DOM(PMAP_DOMAIN_KERNEL);
   6531 	l1pte_setone(pdep + l1slot, npde);
   6532 	PDE_SYNC(pdep + l1slot);
   6533 }
   6534 
   6535 /*
   6536  * pmap_map_entry:
   6537  *
   6538  *	Create a single page mapping.
   6539  */
   6540 void
   6541 pmap_map_entry(vaddr_t l1pt, vaddr_t va, paddr_t pa, int prot, int cache)
   6542 {
   6543 	pd_entry_t * const pdep = (pd_entry_t *) l1pt;
   6544 	const size_t l1slot = l1pte_index(va);
   6545 	pt_entry_t npte;
   6546 	pt_entry_t *ptep;
   6547 
   6548 	KASSERT(((va | pa) & PGOFSET) == 0);
   6549 
   6550 	switch (cache) {
   6551 	case PTE_NOCACHE:
   6552 	default:
   6553 		npte = 0;
   6554 		break;
   6555 
   6556 	case PTE_CACHE:
   6557 		npte = pte_l2_s_cache_mode;
   6558 		break;
   6559 
   6560 	case PTE_PAGETABLE:
   6561 		npte = pte_l2_s_cache_mode_pt;
   6562 		break;
   6563 	}
   6564 
   6565 	if ((pdep[l1slot] & L1_TYPE_MASK) != L1_TYPE_C)
   6566 		panic("pmap_map_entry: no L2 table for VA 0x%08lx", va);
   6567 
   6568 	ptep = (pt_entry_t *) kernel_pt_lookup(l1pte_pa(pdep[l1slot]));
   6569 	if (ptep == NULL)
   6570 		panic("pmap_map_entry: can't find L2 table for VA 0x%08lx", va);
   6571 
   6572 	npte |= L2_S_PROTO | pa | L2_S_PROT(PTE_KERNEL, prot);
   6573 #ifdef ARM_MMU_EXTENDED
   6574 	if (prot & VM_PROT_EXECUTE) {
   6575 		npte &= ~L2_XS_XN;
   6576 	}
   6577 #endif
   6578 	ptep += l2pte_index(va);
   6579 	l2pte_set(ptep, npte, 0);
   6580 	PTE_SYNC(ptep);
   6581 }
   6582 
   6583 /*
   6584  * pmap_link_l2pt:
   6585  *
   6586  *	Link the L2 page table specified by "l2pv" into the L1
   6587  *	page table at the slot for "va".
   6588  */
   6589 void
   6590 pmap_link_l2pt(vaddr_t l1pt, vaddr_t va, pv_addr_t *l2pv)
   6591 {
   6592 	pd_entry_t * const pdep = (pd_entry_t *) l1pt + l1pte_index(va);
   6593 
   6594 	KASSERT((va & ((L1_S_SIZE * (PAGE_SIZE / L2_T_SIZE)) - 1)) == 0);
   6595 	KASSERT((l2pv->pv_pa & PGOFSET) == 0);
   6596 
   6597 	const pd_entry_t npde = L1_S_DOM(PMAP_DOMAIN_KERNEL) | L1_C_PROTO
   6598 	    | l2pv->pv_pa;
   6599 
   6600 	l1pte_set(pdep, npde);
   6601 	PDE_SYNC_RANGE(pdep, PAGE_SIZE / L2_T_SIZE);
   6602 
   6603 	SLIST_INSERT_HEAD(&kernel_pt_list, l2pv, pv_list);
   6604 }
   6605 
   6606 /*
   6607  * pmap_map_chunk:
   6608  *
   6609  *	Map a chunk of memory using the most efficient mappings
   6610  *	possible (section, large page, small page) into the
   6611  *	provided L1 and L2 tables at the specified virtual address.
   6612  */
   6613 vsize_t
   6614 pmap_map_chunk(vaddr_t l1pt, vaddr_t va, paddr_t pa, vsize_t size,
   6615     int prot, int cache)
   6616 {
   6617 	pd_entry_t * const pdep = (pd_entry_t *) l1pt;
   6618 	pt_entry_t f1, f2s, f2l;
   6619 	vsize_t resid;
   6620 
   6621 	resid = (size + (PAGE_SIZE - 1)) & ~(PAGE_SIZE - 1);
   6622 
   6623 	if (l1pt == 0)
   6624 		panic("pmap_map_chunk: no L1 table provided");
   6625 
   6626 #ifdef VERBOSE_INIT_ARM
   6627 	printf("pmap_map_chunk: pa=0x%lx va=0x%lx size=0x%lx resid=0x%lx "
   6628 	    "prot=0x%x cache=%d\n", pa, va, size, resid, prot, cache);
   6629 #endif
   6630 
   6631 	switch (cache) {
   6632 	case PTE_NOCACHE:
   6633 	default:
   6634 		f1 = 0;
   6635 		f2l = 0;
   6636 		f2s = 0;
   6637 		break;
   6638 
   6639 	case PTE_CACHE:
   6640 		f1 = pte_l1_s_cache_mode;
   6641 		f2l = pte_l2_l_cache_mode;
   6642 		f2s = pte_l2_s_cache_mode;
   6643 		break;
   6644 
   6645 	case PTE_PAGETABLE:
   6646 		f1 = pte_l1_s_cache_mode_pt;
   6647 		f2l = pte_l2_l_cache_mode_pt;
   6648 		f2s = pte_l2_s_cache_mode_pt;
   6649 		break;
   6650 	}
   6651 
   6652 	size = resid;
   6653 
   6654 	while (resid > 0) {
   6655 		const size_t l1slot = l1pte_index(va);
   6656 #if (ARM_MMU_V6 + ARM_MMU_V7) > 0
   6657 		/* See if we can use a supersection mapping. */
   6658 		if (L1_SS_PROTO && L1_SS_MAPPABLE_P(va, pa, resid)) {
   6659 			/* Supersection are always domain 0 */
   6660 			const pd_entry_t npde = L1_SS_PROTO | pa
   6661 #ifdef ARM_MMU_EXTENDED_XXX
   6662 			    | ((prot & VM_PROT_EXECUTE) ? 0 : L1_S_V6_XN)
   6663 #endif
   6664 #ifdef ARM_MMU_EXTENDED
   6665 			    | (va & 0x80000000 ? 0 : L1_S_V6_nG)
   6666 #endif
   6667 			    | L1_S_PROT(PTE_KERNEL, prot) | f1;
   6668 #ifdef VERBOSE_INIT_ARM
   6669 			printf("sS");
   6670 #endif
   6671 			l1pte_set(&pdep[l1slot], npde);
   6672 			PDE_SYNC_RANGE(&pdep[l1slot], L1_SS_SIZE / L1_S_SIZE);
   6673 			va += L1_SS_SIZE;
   6674 			pa += L1_SS_SIZE;
   6675 			resid -= L1_SS_SIZE;
   6676 			continue;
   6677 		}
   6678 #endif
   6679 		/* See if we can use a section mapping. */
   6680 		if (L1_S_MAPPABLE_P(va, pa, resid)) {
   6681 			const pd_entry_t npde = L1_S_PROTO | pa
   6682 #ifdef ARM_MMU_EXTENDED_XXX
   6683 			    | ((prot & VM_PROT_EXECUTE) ? 0 : L1_S_V6_XN)
   6684 #endif
   6685 #ifdef ARM_MMU_EXTENDED
   6686 			    | (va & 0x80000000 ? 0 : L1_S_V6_nG)
   6687 #endif
   6688 			    | L1_S_PROT(PTE_KERNEL, prot) | f1
   6689 			    | L1_S_DOM(PMAP_DOMAIN_KERNEL);
   6690 #ifdef VERBOSE_INIT_ARM
   6691 			printf("S");
   6692 #endif
   6693 			l1pte_set(&pdep[l1slot], npde);
   6694 			PDE_SYNC(&pdep[l1slot]);
   6695 			va += L1_S_SIZE;
   6696 			pa += L1_S_SIZE;
   6697 			resid -= L1_S_SIZE;
   6698 			continue;
   6699 		}
   6700 
   6701 		/*
   6702 		 * Ok, we're going to use an L2 table.  Make sure
   6703 		 * one is actually in the corresponding L1 slot
   6704 		 * for the current VA.
   6705 		 */
   6706 		if ((pdep[l1slot] & L1_TYPE_MASK) != L1_TYPE_C)
   6707 			panic("%s: no L2 table for VA %#lx", __func__, va);
   6708 
   6709 		pt_entry_t *ptep = (pt_entry_t *) kernel_pt_lookup(l1pte_pa(pdep[l1slot]));
   6710 		if (ptep == NULL)
   6711 			panic("%s: can't find L2 table for VA %#lx", __func__,
   6712 			    va);
   6713 
   6714 		ptep += l2pte_index(va);
   6715 
   6716 		/* See if we can use a L2 large page mapping. */
   6717 		if (L2_L_MAPPABLE_P(va, pa, resid)) {
   6718 			const pt_entry_t npte = L2_L_PROTO | pa
   6719 #ifdef ARM_MMU_EXTENDED_XXX
   6720 			    | ((prot & VM_PROT_EXECUTE) ? 0 : L2_XS_L_XN)
   6721 #endif
   6722 #ifdef ARM_MMU_EXTENDED
   6723 			    | (va & 0x80000000 ? 0 : L2_XS_nG)
   6724 #endif
   6725 			    | L2_L_PROT(PTE_KERNEL, prot) | f2l;
   6726 #ifdef VERBOSE_INIT_ARM
   6727 			printf("L");
   6728 #endif
   6729 			l2pte_set(ptep, npte, 0);
   6730 			PTE_SYNC_RANGE(ptep, L2_L_SIZE / L2_S_SIZE);
   6731 			va += L2_L_SIZE;
   6732 			pa += L2_L_SIZE;
   6733 			resid -= L2_L_SIZE;
   6734 			continue;
   6735 		}
   6736 
   6737 		/* Use a small page mapping. */
   6738 #ifdef VERBOSE_INIT_ARM
   6739 		printf("P");
   6740 #endif
   6741 		const pt_entry_t npte = L2_S_PROTO | pa
   6742 #ifdef ARM_MMU_EXTENDED_XXX
   6743 		    | ((prot & VM_PROT_EXECUTE) ? 0 : L2_XS_XN)
   6744 #endif
   6745 #ifdef ARM_MMU_EXTENDED
   6746 		    | (va & 0x80000000 ? 0 : L2_XS_nG)
   6747 #endif
   6748 		    | L2_S_PROT(PTE_KERNEL, prot) | f2s;
   6749 		l2pte_set(ptep, npte, 0);
   6750 		PTE_SYNC(ptep);
   6751 		va += PAGE_SIZE;
   6752 		pa += PAGE_SIZE;
   6753 		resid -= PAGE_SIZE;
   6754 	}
   6755 #ifdef VERBOSE_INIT_ARM
   6756 	printf("\n");
   6757 #endif
   6758 	return (size);
   6759 }
   6760 
   6761 /********************** Static device map routines ***************************/
   6762 
   6763 static const struct pmap_devmap *pmap_devmap_table;
   6764 
   6765 /*
   6766  * Register the devmap table.  This is provided in case early console
   6767  * initialization needs to register mappings created by bootstrap code
   6768  * before pmap_devmap_bootstrap() is called.
   6769  */
   6770 void
   6771 pmap_devmap_register(const struct pmap_devmap *table)
   6772 {
   6773 
   6774 	pmap_devmap_table = table;
   6775 }
   6776 
   6777 /*
   6778  * Map all of the static regions in the devmap table, and remember
   6779  * the devmap table so other parts of the kernel can look up entries
   6780  * later.
   6781  */
   6782 void
   6783 pmap_devmap_bootstrap(vaddr_t l1pt, const struct pmap_devmap *table)
   6784 {
   6785 	int i;
   6786 
   6787 	pmap_devmap_table = table;
   6788 
   6789 	for (i = 0; pmap_devmap_table[i].pd_size != 0; i++) {
   6790 #ifdef VERBOSE_INIT_ARM
   6791 		printf("devmap: %08lx -> %08lx @ %08lx\n",
   6792 		    pmap_devmap_table[i].pd_pa,
   6793 		    pmap_devmap_table[i].pd_pa +
   6794 			pmap_devmap_table[i].pd_size - 1,
   6795 		    pmap_devmap_table[i].pd_va);
   6796 #endif
   6797 		pmap_map_chunk(l1pt, pmap_devmap_table[i].pd_va,
   6798 		    pmap_devmap_table[i].pd_pa,
   6799 		    pmap_devmap_table[i].pd_size,
   6800 		    pmap_devmap_table[i].pd_prot,
   6801 		    pmap_devmap_table[i].pd_cache);
   6802 	}
   6803 }
   6804 
   6805 const struct pmap_devmap *
   6806 pmap_devmap_find_pa(paddr_t pa, psize_t size)
   6807 {
   6808 	uint64_t endpa;
   6809 	int i;
   6810 
   6811 	if (pmap_devmap_table == NULL)
   6812 		return (NULL);
   6813 
   6814 	endpa = (uint64_t)pa + (uint64_t)(size - 1);
   6815 
   6816 	for (i = 0; pmap_devmap_table[i].pd_size != 0; i++) {
   6817 		if (pa >= pmap_devmap_table[i].pd_pa &&
   6818 		    endpa <= (uint64_t)pmap_devmap_table[i].pd_pa +
   6819 			     (uint64_t)(pmap_devmap_table[i].pd_size - 1))
   6820 			return (&pmap_devmap_table[i]);
   6821 	}
   6822 
   6823 	return (NULL);
   6824 }
   6825 
   6826 const struct pmap_devmap *
   6827 pmap_devmap_find_va(vaddr_t va, vsize_t size)
   6828 {
   6829 	int i;
   6830 
   6831 	if (pmap_devmap_table == NULL)
   6832 		return (NULL);
   6833 
   6834 	for (i = 0; pmap_devmap_table[i].pd_size != 0; i++) {
   6835 		if (va >= pmap_devmap_table[i].pd_va &&
   6836 		    va + size - 1 <= pmap_devmap_table[i].pd_va +
   6837 				     pmap_devmap_table[i].pd_size - 1)
   6838 			return (&pmap_devmap_table[i]);
   6839 	}
   6840 
   6841 	return (NULL);
   6842 }
   6843 
   6844 /********************** PTE initialization routines **************************/
   6845 
   6846 /*
   6847  * These routines are called when the CPU type is identified to set up
   6848  * the PTE prototypes, cache modes, etc.
   6849  *
   6850  * The variables are always here, just in case modules need to reference
   6851  * them (though, they shouldn't).
   6852  */
   6853 
   6854 pt_entry_t	pte_l1_s_cache_mode;
   6855 pt_entry_t	pte_l1_s_wc_mode;
   6856 pt_entry_t	pte_l1_s_cache_mode_pt;
   6857 pt_entry_t	pte_l1_s_cache_mask;
   6858 
   6859 pt_entry_t	pte_l2_l_cache_mode;
   6860 pt_entry_t	pte_l2_l_wc_mode;
   6861 pt_entry_t	pte_l2_l_cache_mode_pt;
   6862 pt_entry_t	pte_l2_l_cache_mask;
   6863 
   6864 pt_entry_t	pte_l2_s_cache_mode;
   6865 pt_entry_t	pte_l2_s_wc_mode;
   6866 pt_entry_t	pte_l2_s_cache_mode_pt;
   6867 pt_entry_t	pte_l2_s_cache_mask;
   6868 
   6869 pt_entry_t	pte_l1_s_prot_u;
   6870 pt_entry_t	pte_l1_s_prot_w;
   6871 pt_entry_t	pte_l1_s_prot_ro;
   6872 pt_entry_t	pte_l1_s_prot_mask;
   6873 
   6874 pt_entry_t	pte_l2_s_prot_u;
   6875 pt_entry_t	pte_l2_s_prot_w;
   6876 pt_entry_t	pte_l2_s_prot_ro;
   6877 pt_entry_t	pte_l2_s_prot_mask;
   6878 
   6879 pt_entry_t	pte_l2_l_prot_u;
   6880 pt_entry_t	pte_l2_l_prot_w;
   6881 pt_entry_t	pte_l2_l_prot_ro;
   6882 pt_entry_t	pte_l2_l_prot_mask;
   6883 
   6884 pt_entry_t	pte_l1_ss_proto;
   6885 pt_entry_t	pte_l1_s_proto;
   6886 pt_entry_t	pte_l1_c_proto;
   6887 pt_entry_t	pte_l2_s_proto;
   6888 
   6889 void		(*pmap_copy_page_func)(paddr_t, paddr_t);
   6890 void		(*pmap_zero_page_func)(paddr_t);
   6891 
   6892 #if (ARM_MMU_GENERIC + ARM_MMU_SA1 + ARM_MMU_V6 + ARM_MMU_V7) != 0
   6893 void
   6894 pmap_pte_init_generic(void)
   6895 {
   6896 
   6897 	pte_l1_s_cache_mode = L1_S_B|L1_S_C;
   6898 	pte_l1_s_wc_mode = L1_S_B;
   6899 	pte_l1_s_cache_mask = L1_S_CACHE_MASK_generic;
   6900 
   6901 	pte_l2_l_cache_mode = L2_B|L2_C;
   6902 	pte_l2_l_wc_mode = L2_B;
   6903 	pte_l2_l_cache_mask = L2_L_CACHE_MASK_generic;
   6904 
   6905 	pte_l2_s_cache_mode = L2_B|L2_C;
   6906 	pte_l2_s_wc_mode = L2_B;
   6907 	pte_l2_s_cache_mask = L2_S_CACHE_MASK_generic;
   6908 
   6909 	/*
   6910 	 * If we have a write-through cache, set B and C.  If
   6911 	 * we have a write-back cache, then we assume setting
   6912 	 * only C will make those pages write-through (except for those
   6913 	 * Cortex CPUs which can read the L1 caches).
   6914 	 */
   6915 	if (cpufuncs.cf_dcache_wb_range == (void *) cpufunc_nullop
   6916 #if ARM_MMU_V7 > 0
   6917 	    || CPU_ID_CORTEX_P(curcpu()->ci_arm_cpuid)
   6918 #endif
   6919 #if ARM_MMU_V6 > 0
   6920 	    || CPU_ID_ARM11_P(curcpu()->ci_arm_cpuid) /* arm116 errata 399234 */
   6921 #endif
   6922 	    || false) {
   6923 		pte_l1_s_cache_mode_pt = L1_S_B|L1_S_C;
   6924 		pte_l2_l_cache_mode_pt = L2_B|L2_C;
   6925 		pte_l2_s_cache_mode_pt = L2_B|L2_C;
   6926 	} else {
   6927 		pte_l1_s_cache_mode_pt = L1_S_C;	/* write through */
   6928 		pte_l2_l_cache_mode_pt = L2_C;		/* write through */
   6929 		pte_l2_s_cache_mode_pt = L2_C;		/* write through */
   6930 	}
   6931 
   6932 	pte_l1_s_prot_u = L1_S_PROT_U_generic;
   6933 	pte_l1_s_prot_w = L1_S_PROT_W_generic;
   6934 	pte_l1_s_prot_ro = L1_S_PROT_RO_generic;
   6935 	pte_l1_s_prot_mask = L1_S_PROT_MASK_generic;
   6936 
   6937 	pte_l2_s_prot_u = L2_S_PROT_U_generic;
   6938 	pte_l2_s_prot_w = L2_S_PROT_W_generic;
   6939 	pte_l2_s_prot_ro = L2_S_PROT_RO_generic;
   6940 	pte_l2_s_prot_mask = L2_S_PROT_MASK_generic;
   6941 
   6942 	pte_l2_l_prot_u = L2_L_PROT_U_generic;
   6943 	pte_l2_l_prot_w = L2_L_PROT_W_generic;
   6944 	pte_l2_l_prot_ro = L2_L_PROT_RO_generic;
   6945 	pte_l2_l_prot_mask = L2_L_PROT_MASK_generic;
   6946 
   6947 	pte_l1_ss_proto = L1_SS_PROTO_generic;
   6948 	pte_l1_s_proto = L1_S_PROTO_generic;
   6949 	pte_l1_c_proto = L1_C_PROTO_generic;
   6950 	pte_l2_s_proto = L2_S_PROTO_generic;
   6951 
   6952 	pmap_copy_page_func = pmap_copy_page_generic;
   6953 	pmap_zero_page_func = pmap_zero_page_generic;
   6954 }
   6955 
   6956 #if defined(CPU_ARM8)
   6957 void
   6958 pmap_pte_init_arm8(void)
   6959 {
   6960 
   6961 	/*
   6962 	 * ARM8 is compatible with generic, but we need to use
   6963 	 * the page tables uncached.
   6964 	 */
   6965 	pmap_pte_init_generic();
   6966 
   6967 	pte_l1_s_cache_mode_pt = 0;
   6968 	pte_l2_l_cache_mode_pt = 0;
   6969 	pte_l2_s_cache_mode_pt = 0;
   6970 }
   6971 #endif /* CPU_ARM8 */
   6972 
   6973 #if defined(CPU_ARM9) && defined(ARM9_CACHE_WRITE_THROUGH)
   6974 void
   6975 pmap_pte_init_arm9(void)
   6976 {
   6977 
   6978 	/*
   6979 	 * ARM9 is compatible with generic, but we want to use
   6980 	 * write-through caching for now.
   6981 	 */
   6982 	pmap_pte_init_generic();
   6983 
   6984 	pte_l1_s_cache_mode = L1_S_C;
   6985 	pte_l2_l_cache_mode = L2_C;
   6986 	pte_l2_s_cache_mode = L2_C;
   6987 
   6988 	pte_l1_s_wc_mode = L1_S_B;
   6989 	pte_l2_l_wc_mode = L2_B;
   6990 	pte_l2_s_wc_mode = L2_B;
   6991 
   6992 	pte_l1_s_cache_mode_pt = L1_S_C;
   6993 	pte_l2_l_cache_mode_pt = L2_C;
   6994 	pte_l2_s_cache_mode_pt = L2_C;
   6995 }
   6996 #endif /* CPU_ARM9 && ARM9_CACHE_WRITE_THROUGH */
   6997 #endif /* (ARM_MMU_GENERIC + ARM_MMU_SA1 + ARM_MMU_V6) != 0 */
   6998 
   6999 #if defined(CPU_ARM10)
   7000 void
   7001 pmap_pte_init_arm10(void)
   7002 {
   7003 
   7004 	/*
   7005 	 * ARM10 is compatible with generic, but we want to use
   7006 	 * write-through caching for now.
   7007 	 */
   7008 	pmap_pte_init_generic();
   7009 
   7010 	pte_l1_s_cache_mode = L1_S_B | L1_S_C;
   7011 	pte_l2_l_cache_mode = L2_B | L2_C;
   7012 	pte_l2_s_cache_mode = L2_B | L2_C;
   7013 
   7014 	pte_l1_s_cache_mode = L1_S_B;
   7015 	pte_l2_l_cache_mode = L2_B;
   7016 	pte_l2_s_cache_mode = L2_B;
   7017 
   7018 	pte_l1_s_cache_mode_pt = L1_S_C;
   7019 	pte_l2_l_cache_mode_pt = L2_C;
   7020 	pte_l2_s_cache_mode_pt = L2_C;
   7021 
   7022 }
   7023 #endif /* CPU_ARM10 */
   7024 
   7025 #if defined(CPU_ARM11) && defined(ARM11_CACHE_WRITE_THROUGH)
   7026 void
   7027 pmap_pte_init_arm11(void)
   7028 {
   7029 
   7030 	/*
   7031 	 * ARM11 is compatible with generic, but we want to use
   7032 	 * write-through caching for now.
   7033 	 */
   7034 	pmap_pte_init_generic();
   7035 
   7036 	pte_l1_s_cache_mode = L1_S_C;
   7037 	pte_l2_l_cache_mode = L2_C;
   7038 	pte_l2_s_cache_mode = L2_C;
   7039 
   7040 	pte_l1_s_wc_mode = L1_S_B;
   7041 	pte_l2_l_wc_mode = L2_B;
   7042 	pte_l2_s_wc_mode = L2_B;
   7043 
   7044 	pte_l1_s_cache_mode_pt = L1_S_C;
   7045 	pte_l2_l_cache_mode_pt = L2_C;
   7046 	pte_l2_s_cache_mode_pt = L2_C;
   7047 }
   7048 #endif /* CPU_ARM11 && ARM11_CACHE_WRITE_THROUGH */
   7049 
   7050 #if ARM_MMU_SA1 == 1
   7051 void
   7052 pmap_pte_init_sa1(void)
   7053 {
   7054 
   7055 	/*
   7056 	 * The StrongARM SA-1 cache does not have a write-through
   7057 	 * mode.  So, do the generic initialization, then reset
   7058 	 * the page table cache mode to B=1,C=1, and note that
   7059 	 * the PTEs need to be sync'd.
   7060 	 */
   7061 	pmap_pte_init_generic();
   7062 
   7063 	pte_l1_s_cache_mode_pt = L1_S_B|L1_S_C;
   7064 	pte_l2_l_cache_mode_pt = L2_B|L2_C;
   7065 	pte_l2_s_cache_mode_pt = L2_B|L2_C;
   7066 
   7067 	pmap_needs_pte_sync = 1;
   7068 }
   7069 #endif /* ARM_MMU_SA1 == 1*/
   7070 
   7071 #if ARM_MMU_XSCALE == 1
   7072 #if (ARM_NMMUS > 1)
   7073 static u_int xscale_use_minidata;
   7074 #endif
   7075 
   7076 void
   7077 pmap_pte_init_xscale(void)
   7078 {
   7079 	uint32_t auxctl;
   7080 	int write_through = 0;
   7081 
   7082 	pte_l1_s_cache_mode = L1_S_B|L1_S_C;
   7083 	pte_l1_s_wc_mode = L1_S_B;
   7084 	pte_l1_s_cache_mask = L1_S_CACHE_MASK_xscale;
   7085 
   7086 	pte_l2_l_cache_mode = L2_B|L2_C;
   7087 	pte_l2_l_wc_mode = L2_B;
   7088 	pte_l2_l_cache_mask = L2_L_CACHE_MASK_xscale;
   7089 
   7090 	pte_l2_s_cache_mode = L2_B|L2_C;
   7091 	pte_l2_s_wc_mode = L2_B;
   7092 	pte_l2_s_cache_mask = L2_S_CACHE_MASK_xscale;
   7093 
   7094 	pte_l1_s_cache_mode_pt = L1_S_C;
   7095 	pte_l2_l_cache_mode_pt = L2_C;
   7096 	pte_l2_s_cache_mode_pt = L2_C;
   7097 
   7098 #ifdef XSCALE_CACHE_READ_WRITE_ALLOCATE
   7099 	/*
   7100 	 * The XScale core has an enhanced mode where writes that
   7101 	 * miss the cache cause a cache line to be allocated.  This
   7102 	 * is significantly faster than the traditional, write-through
   7103 	 * behavior of this case.
   7104 	 */
   7105 	pte_l1_s_cache_mode |= L1_S_XS_TEX(TEX_XSCALE_X);
   7106 	pte_l2_l_cache_mode |= L2_XS_L_TEX(TEX_XSCALE_X);
   7107 	pte_l2_s_cache_mode |= L2_XS_T_TEX(TEX_XSCALE_X);
   7108 #endif /* XSCALE_CACHE_READ_WRITE_ALLOCATE */
   7109 
   7110 #ifdef XSCALE_CACHE_WRITE_THROUGH
   7111 	/*
   7112 	 * Some versions of the XScale core have various bugs in
   7113 	 * their cache units, the work-around for which is to run
   7114 	 * the cache in write-through mode.  Unfortunately, this
   7115 	 * has a major (negative) impact on performance.  So, we
   7116 	 * go ahead and run fast-and-loose, in the hopes that we
   7117 	 * don't line up the planets in a way that will trip the
   7118 	 * bugs.
   7119 	 *
   7120 	 * However, we give you the option to be slow-but-correct.
   7121 	 */
   7122 	write_through = 1;
   7123 #elif defined(XSCALE_CACHE_WRITE_BACK)
   7124 	/* force write back cache mode */
   7125 	write_through = 0;
   7126 #elif defined(CPU_XSCALE_PXA250) || defined(CPU_XSCALE_PXA270)
   7127 	/*
   7128 	 * Intel PXA2[15]0 processors are known to have a bug in
   7129 	 * write-back cache on revision 4 and earlier (stepping
   7130 	 * A[01] and B[012]).  Fixed for C0 and later.
   7131 	 */
   7132 	{
   7133 		uint32_t id, type;
   7134 
   7135 		id = cpufunc_id();
   7136 		type = id & ~(CPU_ID_XSCALE_COREREV_MASK|CPU_ID_REVISION_MASK);
   7137 
   7138 		if (type == CPU_ID_PXA250 || type == CPU_ID_PXA210) {
   7139 			if ((id & CPU_ID_REVISION_MASK) < 5) {
   7140 				/* write through for stepping A0-1 and B0-2 */
   7141 				write_through = 1;
   7142 			}
   7143 		}
   7144 	}
   7145 #endif /* XSCALE_CACHE_WRITE_THROUGH */
   7146 
   7147 	if (write_through) {
   7148 		pte_l1_s_cache_mode = L1_S_C;
   7149 		pte_l2_l_cache_mode = L2_C;
   7150 		pte_l2_s_cache_mode = L2_C;
   7151 	}
   7152 
   7153 #if (ARM_NMMUS > 1)
   7154 	xscale_use_minidata = 1;
   7155 #endif
   7156 
   7157 	pte_l1_s_prot_u = L1_S_PROT_U_xscale;
   7158 	pte_l1_s_prot_w = L1_S_PROT_W_xscale;
   7159 	pte_l1_s_prot_ro = L1_S_PROT_RO_xscale;
   7160 	pte_l1_s_prot_mask = L1_S_PROT_MASK_xscale;
   7161 
   7162 	pte_l2_s_prot_u = L2_S_PROT_U_xscale;
   7163 	pte_l2_s_prot_w = L2_S_PROT_W_xscale;
   7164 	pte_l2_s_prot_ro = L2_S_PROT_RO_xscale;
   7165 	pte_l2_s_prot_mask = L2_S_PROT_MASK_xscale;
   7166 
   7167 	pte_l2_l_prot_u = L2_L_PROT_U_xscale;
   7168 	pte_l2_l_prot_w = L2_L_PROT_W_xscale;
   7169 	pte_l2_l_prot_ro = L2_L_PROT_RO_xscale;
   7170 	pte_l2_l_prot_mask = L2_L_PROT_MASK_xscale;
   7171 
   7172 	pte_l1_ss_proto = L1_SS_PROTO_xscale;
   7173 	pte_l1_s_proto = L1_S_PROTO_xscale;
   7174 	pte_l1_c_proto = L1_C_PROTO_xscale;
   7175 	pte_l2_s_proto = L2_S_PROTO_xscale;
   7176 
   7177 	pmap_copy_page_func = pmap_copy_page_xscale;
   7178 	pmap_zero_page_func = pmap_zero_page_xscale;
   7179 
   7180 	/*
   7181 	 * Disable ECC protection of page table access, for now.
   7182 	 */
   7183 	__asm volatile("mrc p15, 0, %0, c1, c0, 1" : "=r" (auxctl));
   7184 	auxctl &= ~XSCALE_AUXCTL_P;
   7185 	__asm volatile("mcr p15, 0, %0, c1, c0, 1" : : "r" (auxctl));
   7186 }
   7187 
   7188 /*
   7189  * xscale_setup_minidata:
   7190  *
   7191  *	Set up the mini-data cache clean area.  We require the
   7192  *	caller to allocate the right amount of physically and
   7193  *	virtually contiguous space.
   7194  */
   7195 void
   7196 xscale_setup_minidata(vaddr_t l1pt, vaddr_t va, paddr_t pa)
   7197 {
   7198 	extern vaddr_t xscale_minidata_clean_addr;
   7199 	extern vsize_t xscale_minidata_clean_size; /* already initialized */
   7200 	pd_entry_t *pde = (pd_entry_t *) l1pt;
   7201 	vsize_t size;
   7202 	uint32_t auxctl;
   7203 
   7204 	xscale_minidata_clean_addr = va;
   7205 
   7206 	/* Round it to page size. */
   7207 	size = (xscale_minidata_clean_size + L2_S_OFFSET) & L2_S_FRAME;
   7208 
   7209 	for (; size != 0;
   7210 	     va += L2_S_SIZE, pa += L2_S_SIZE, size -= L2_S_SIZE) {
   7211 		const size_t l1slot = l1pte_index(va);
   7212 		pt_entry_t *ptep = (pt_entry_t *) kernel_pt_lookup(l1pte_pa(pde[l1slot]));
   7213 		if (ptep == NULL)
   7214 			panic("xscale_setup_minidata: can't find L2 table for "
   7215 			    "VA 0x%08lx", va);
   7216 
   7217 		ptep += l2pte_index(va);
   7218 		pt_entry_t opte = *ptep;
   7219 		l2pte_set(ptep,
   7220 		    L2_S_PROTO | pa | L2_S_PROT(PTE_KERNEL, VM_PROT_READ)
   7221 		    | L2_C | L2_XS_T_TEX(TEX_XSCALE_X), opte);
   7222 	}
   7223 
   7224 	/*
   7225 	 * Configure the mini-data cache for write-back with
   7226 	 * read/write-allocate.
   7227 	 *
   7228 	 * NOTE: In order to reconfigure the mini-data cache, we must
   7229 	 * make sure it contains no valid data!  In order to do that,
   7230 	 * we must issue a global data cache invalidate command!
   7231 	 *
   7232 	 * WE ASSUME WE ARE RUNNING UN-CACHED WHEN THIS ROUTINE IS CALLED!
   7233 	 * THIS IS VERY IMPORTANT!
   7234 	 */
   7235 
   7236 	/* Invalidate data and mini-data. */
   7237 	__asm volatile("mcr p15, 0, %0, c7, c6, 0" : : "r" (0));
   7238 	__asm volatile("mrc p15, 0, %0, c1, c0, 1" : "=r" (auxctl));
   7239 	auxctl = (auxctl & ~XSCALE_AUXCTL_MD_MASK) | XSCALE_AUXCTL_MD_WB_RWA;
   7240 	__asm volatile("mcr p15, 0, %0, c1, c0, 1" : : "r" (auxctl));
   7241 }
   7242 
   7243 /*
   7244  * Change the PTEs for the specified kernel mappings such that they
   7245  * will use the mini data cache instead of the main data cache.
   7246  */
   7247 void
   7248 pmap_uarea(vaddr_t va)
   7249 {
   7250 	vaddr_t next_bucket, eva;
   7251 
   7252 #if (ARM_NMMUS > 1)
   7253 	if (xscale_use_minidata == 0)
   7254 		return;
   7255 #endif
   7256 
   7257 	eva = va + USPACE;
   7258 
   7259 	while (va < eva) {
   7260 		next_bucket = L2_NEXT_BUCKET_VA(va);
   7261 		if (next_bucket > eva)
   7262 			next_bucket = eva;
   7263 
   7264 		struct l2_bucket *l2b = pmap_get_l2_bucket(pmap_kernel(), va);
   7265 		KDASSERT(l2b != NULL);
   7266 
   7267 		pt_entry_t * const sptep = &l2b->l2b_kva[l2pte_index(va)];
   7268 		pt_entry_t *ptep = sptep;
   7269 
   7270 		while (va < next_bucket) {
   7271 			const pt_entry_t opte = *ptep;
   7272 			if (!l2pte_minidata_p(opte)) {
   7273 				cpu_dcache_wbinv_range(va, PAGE_SIZE);
   7274 				cpu_tlb_flushD_SE(va);
   7275 				l2pte_set(ptep, opte & ~L2_B, opte);
   7276 			}
   7277 			ptep += PAGE_SIZE / L2_S_SIZE;
   7278 			va += PAGE_SIZE;
   7279 		}
   7280 		PTE_SYNC_RANGE(sptep, (u_int)(ptep - sptep));
   7281 	}
   7282 	cpu_cpwait();
   7283 }
   7284 #endif /* ARM_MMU_XSCALE == 1 */
   7285 
   7286 
   7287 #if defined(CPU_ARM11MPCORE)
   7288 
   7289 void
   7290 pmap_pte_init_arm11mpcore(void)
   7291 {
   7292 
   7293 	/* cache mode is controlled by 5 bits (B, C, TEX) */
   7294 	pte_l1_s_cache_mask = L1_S_CACHE_MASK_armv6;
   7295 	pte_l2_l_cache_mask = L2_L_CACHE_MASK_armv6;
   7296 #if defined(ARM11MPCORE_COMPAT_MMU) || defined(ARMV6_EXTENDED_SMALL_PAGE)
   7297 	/* use extended small page (without APn, with TEX) */
   7298 	pte_l2_s_cache_mask = L2_XS_CACHE_MASK_armv6;
   7299 #else
   7300 	pte_l2_s_cache_mask = L2_S_CACHE_MASK_armv6c;
   7301 #endif
   7302 
   7303 	/* write-back, write-allocate */
   7304 	pte_l1_s_cache_mode = L1_S_C | L1_S_B | L1_S_V6_TEX(0x01);
   7305 	pte_l2_l_cache_mode = L2_C | L2_B | L2_V6_L_TEX(0x01);
   7306 #if defined(ARM11MPCORE_COMPAT_MMU) || defined(ARMV6_EXTENDED_SMALL_PAGE)
   7307 	pte_l2_s_cache_mode = L2_C | L2_B | L2_V6_XS_TEX(0x01);
   7308 #else
   7309 	/* no TEX. read-allocate */
   7310 	pte_l2_s_cache_mode = L2_C | L2_B;
   7311 #endif
   7312 	/*
   7313 	 * write-back, write-allocate for page tables.
   7314 	 */
   7315 	pte_l1_s_cache_mode_pt = L1_S_C | L1_S_B | L1_S_V6_TEX(0x01);
   7316 	pte_l2_l_cache_mode_pt = L2_C | L2_B | L2_V6_L_TEX(0x01);
   7317 #if defined(ARM11MPCORE_COMPAT_MMU) || defined(ARMV6_EXTENDED_SMALL_PAGE)
   7318 	pte_l2_s_cache_mode_pt = L2_C | L2_B | L2_V6_XS_TEX(0x01);
   7319 #else
   7320 	pte_l2_s_cache_mode_pt = L2_C | L2_B;
   7321 #endif
   7322 
   7323 	pte_l1_s_prot_u = L1_S_PROT_U_armv6;
   7324 	pte_l1_s_prot_w = L1_S_PROT_W_armv6;
   7325 	pte_l1_s_prot_ro = L1_S_PROT_RO_armv6;
   7326 	pte_l1_s_prot_mask = L1_S_PROT_MASK_armv6;
   7327 
   7328 #if defined(ARM11MPCORE_COMPAT_MMU) || defined(ARMV6_EXTENDED_SMALL_PAGE)
   7329 	pte_l2_s_prot_u = L2_S_PROT_U_armv6n;
   7330 	pte_l2_s_prot_w = L2_S_PROT_W_armv6n;
   7331 	pte_l2_s_prot_ro = L2_S_PROT_RO_armv6n;
   7332 	pte_l2_s_prot_mask = L2_S_PROT_MASK_armv6n;
   7333 
   7334 #else
   7335 	/* with AP[0..3] */
   7336 	pte_l2_s_prot_u = L2_S_PROT_U_generic;
   7337 	pte_l2_s_prot_w = L2_S_PROT_W_generic;
   7338 	pte_l2_s_prot_ro = L2_S_PROT_RO_generic;
   7339 	pte_l2_s_prot_mask = L2_S_PROT_MASK_generic;
   7340 #endif
   7341 
   7342 #ifdef	ARM11MPCORE_COMPAT_MMU
   7343 	/* with AP[0..3] */
   7344 	pte_l2_l_prot_u = L2_L_PROT_U_generic;
   7345 	pte_l2_l_prot_w = L2_L_PROT_W_generic;
   7346 	pte_l2_l_prot_ro = L2_L_PROT_RO_generic;
   7347 	pte_l2_l_prot_mask = L2_L_PROT_MASK_generic;
   7348 
   7349 	pte_l1_ss_proto = L1_SS_PROTO_armv6;
   7350 	pte_l1_s_proto = L1_S_PROTO_armv6;
   7351 	pte_l1_c_proto = L1_C_PROTO_armv6;
   7352 	pte_l2_s_proto = L2_S_PROTO_armv6c;
   7353 #else
   7354 	pte_l2_l_prot_u = L2_L_PROT_U_armv6n;
   7355 	pte_l2_l_prot_w = L2_L_PROT_W_armv6n;
   7356 	pte_l2_l_prot_ro = L2_L_PROT_RO_armv6n;
   7357 	pte_l2_l_prot_mask = L2_L_PROT_MASK_armv6n;
   7358 
   7359 	pte_l1_ss_proto = L1_SS_PROTO_armv6;
   7360 	pte_l1_s_proto = L1_S_PROTO_armv6;
   7361 	pte_l1_c_proto = L1_C_PROTO_armv6;
   7362 	pte_l2_s_proto = L2_S_PROTO_armv6n;
   7363 #endif
   7364 
   7365 	pmap_copy_page_func = pmap_copy_page_generic;
   7366 	pmap_zero_page_func = pmap_zero_page_generic;
   7367 	pmap_needs_pte_sync = 1;
   7368 }
   7369 #endif	/* CPU_ARM11MPCORE */
   7370 
   7371 
   7372 #if ARM_MMU_V7 == 1
   7373 void
   7374 pmap_pte_init_armv7(void)
   7375 {
   7376 	/*
   7377 	 * The ARMv7-A MMU is mostly compatible with generic. If the
   7378 	 * AP field is zero, that now means "no access" rather than
   7379 	 * read-only. The prototypes are a little different because of
   7380 	 * the XN bit.
   7381 	 */
   7382 	pmap_pte_init_generic();
   7383 
   7384 	pmap_needs_pte_sync = 1;
   7385 
   7386 	pte_l1_s_cache_mask = L1_S_CACHE_MASK_armv7;
   7387 	pte_l2_l_cache_mask = L2_L_CACHE_MASK_armv7;
   7388 	pte_l2_s_cache_mask = L2_S_CACHE_MASK_armv7;
   7389 
   7390 	/*
   7391 	 * If the core support coherent walk then updates to translation tables
   7392 	 * do not require a clean to the point of unification to ensure
   7393 	 * visibility by subsequent translation table walks.  That means we can
   7394 	 * map everything shareable and cached and the right thing will happen.
   7395 	 */
   7396         if (__SHIFTOUT(armreg_mmfr3_read(), __BITS(23,20))) {
   7397 		pmap_needs_pte_sync = 0;
   7398 
   7399 		/*
   7400 		 * write-back, no write-allocate, shareable for normal pages.
   7401 		 */
   7402 		pte_l1_s_cache_mode |= L1_S_V6_S;
   7403 		pte_l2_l_cache_mode |= L2_XS_S;
   7404 		pte_l2_s_cache_mode |= L2_XS_S;
   7405 	}
   7406 
   7407 	/*
   7408 	 * Page tables are just all other memory.  We can use write-back since
   7409 	 * pmap_needs_pte_sync is 1 (or the MMU can read out of cache).
   7410 	 */
   7411 	pte_l1_s_cache_mode_pt = pte_l1_s_cache_mode;
   7412 	pte_l2_l_cache_mode_pt = pte_l2_l_cache_mode;
   7413 	pte_l2_s_cache_mode_pt = pte_l2_s_cache_mode;
   7414 
   7415 	/*
   7416 	 * Check the Memory Model Features to see if this CPU supports
   7417 	 * the TLBIASID coproc op.
   7418 	 */
   7419 	if (__SHIFTOUT(armreg_mmfr2_read(), __BITS(16,19)) >= 2) {
   7420 		arm_has_tlbiasid_p = true;
   7421 	}
   7422 
   7423 	pte_l1_s_prot_u = L1_S_PROT_U_armv7;
   7424 	pte_l1_s_prot_w = L1_S_PROT_W_armv7;
   7425 	pte_l1_s_prot_ro = L1_S_PROT_RO_armv7;
   7426 	pte_l1_s_prot_mask = L1_S_PROT_MASK_armv7;
   7427 
   7428 	pte_l2_s_prot_u = L2_S_PROT_U_armv7;
   7429 	pte_l2_s_prot_w = L2_S_PROT_W_armv7;
   7430 	pte_l2_s_prot_ro = L2_S_PROT_RO_armv7;
   7431 	pte_l2_s_prot_mask = L2_S_PROT_MASK_armv7;
   7432 
   7433 	pte_l2_l_prot_u = L2_L_PROT_U_armv7;
   7434 	pte_l2_l_prot_w = L2_L_PROT_W_armv7;
   7435 	pte_l2_l_prot_ro = L2_L_PROT_RO_armv7;
   7436 	pte_l2_l_prot_mask = L2_L_PROT_MASK_armv7;
   7437 
   7438 	pte_l1_ss_proto = L1_SS_PROTO_armv7;
   7439 	pte_l1_s_proto = L1_S_PROTO_armv7;
   7440 	pte_l1_c_proto = L1_C_PROTO_armv7;
   7441 	pte_l2_s_proto = L2_S_PROTO_armv7;
   7442 
   7443 }
   7444 #endif /* ARM_MMU_V7 */
   7445 
   7446 /*
   7447  * return the PA of the current L1 table, for use when handling a crash dump
   7448  */
   7449 uint32_t
   7450 pmap_kernel_L1_addr(void)
   7451 {
   7452 #ifdef ARM_MMU_EXTENDED
   7453 	return pmap_kernel()->pm_l1_pa;
   7454 #else
   7455 	return pmap_kernel()->pm_l1->l1_physaddr;
   7456 #endif
   7457 }
   7458 
   7459 #if defined(DDB)
   7460 /*
   7461  * A couple of ddb-callable functions for dumping pmaps
   7462  */
   7463 void pmap_dump_all(void);
   7464 void pmap_dump(pmap_t);
   7465 
   7466 void
   7467 pmap_dump_all(void)
   7468 {
   7469 	pmap_t pm;
   7470 
   7471 	LIST_FOREACH(pm, &pmap_pmaps, pm_list) {
   7472 		if (pm == pmap_kernel())
   7473 			continue;
   7474 		pmap_dump(pm);
   7475 		printf("\n");
   7476 	}
   7477 }
   7478 
   7479 static pt_entry_t ncptes[64];
   7480 static void pmap_dump_ncpg(pmap_t);
   7481 
   7482 void
   7483 pmap_dump(pmap_t pm)
   7484 {
   7485 	struct l2_dtable *l2;
   7486 	struct l2_bucket *l2b;
   7487 	pt_entry_t *ptep, pte;
   7488 	vaddr_t l2_va, l2b_va, va;
   7489 	int i, j, k, occ, rows = 0;
   7490 
   7491 	if (pm == pmap_kernel())
   7492 		printf("pmap_kernel (%p): ", pm);
   7493 	else
   7494 		printf("user pmap (%p): ", pm);
   7495 
   7496 #ifdef ARM_MMU_EXTENDED
   7497 	printf("l1 at %p\n", pmap_l1_kva(pm));
   7498 #else
   7499 	printf("domain %d, l1 at %p\n", pmap_domain(pm), pmap_l1_kva(pm));
   7500 #endif
   7501 
   7502 	l2_va = 0;
   7503 	for (i = 0; i < L2_SIZE; i++, l2_va += 0x01000000) {
   7504 		l2 = pm->pm_l2[i];
   7505 
   7506 		if (l2 == NULL || l2->l2_occupancy == 0)
   7507 			continue;
   7508 
   7509 		l2b_va = l2_va;
   7510 		for (j = 0; j < L2_BUCKET_SIZE; j++, l2b_va += 0x00100000) {
   7511 			l2b = &l2->l2_bucket[j];
   7512 
   7513 			if (l2b->l2b_occupancy == 0 || l2b->l2b_kva == NULL)
   7514 				continue;
   7515 
   7516 			ptep = l2b->l2b_kva;
   7517 
   7518 			for (k = 0; k < 256 && ptep[k] == 0; k++)
   7519 				;
   7520 
   7521 			k &= ~63;
   7522 			occ = l2b->l2b_occupancy;
   7523 			va = l2b_va + (k * 4096);
   7524 			for (; k < 256; k++, va += 0x1000) {
   7525 				char ch = ' ';
   7526 				if ((k % 64) == 0) {
   7527 					if ((rows % 8) == 0) {
   7528 						printf(
   7529 "          |0000   |8000   |10000  |18000  |20000  |28000  |30000  |38000\n");
   7530 					}
   7531 					printf("%08lx: ", va);
   7532 				}
   7533 
   7534 				ncptes[k & 63] = 0;
   7535 				pte = ptep[k];
   7536 				if (pte == 0) {
   7537 					ch = '.';
   7538 				} else {
   7539 					occ--;
   7540 					switch (pte & 0x0c) {
   7541 					case 0x00:
   7542 						ch = 'D'; /* No cache No buff */
   7543 						break;
   7544 					case 0x04:
   7545 						ch = 'B'; /* No cache buff */
   7546 						break;
   7547 					case 0x08:
   7548 						if (pte & 0x40)
   7549 							ch = 'm';
   7550 						else
   7551 						   ch = 'C'; /* Cache No buff */
   7552 						break;
   7553 					case 0x0c:
   7554 						ch = 'F'; /* Cache Buff */
   7555 						break;
   7556 					}
   7557 
   7558 					if ((pte & L2_S_PROT_U) == L2_S_PROT_U)
   7559 						ch += 0x20;
   7560 
   7561 					if ((pte & 0xc) == 0)
   7562 						ncptes[k & 63] = pte;
   7563 				}
   7564 
   7565 				if ((k % 64) == 63) {
   7566 					rows++;
   7567 					printf("%c\n", ch);
   7568 					pmap_dump_ncpg(pm);
   7569 					if (occ == 0)
   7570 						break;
   7571 				} else
   7572 					printf("%c", ch);
   7573 			}
   7574 		}
   7575 	}
   7576 }
   7577 
   7578 static void
   7579 pmap_dump_ncpg(pmap_t pm)
   7580 {
   7581 	struct vm_page *pg;
   7582 	struct vm_page_md *md;
   7583 	struct pv_entry *pv;
   7584 	int i;
   7585 
   7586 	for (i = 0; i < 63; i++) {
   7587 		if (ncptes[i] == 0)
   7588 			continue;
   7589 
   7590 		pg = PHYS_TO_VM_PAGE(l2pte_pa(ncptes[i]));
   7591 		if (pg == NULL)
   7592 			continue;
   7593 		md = VM_PAGE_TO_MD(pg);
   7594 
   7595 		printf(" pa 0x%08lx: krw %d kro %d urw %d uro %d\n",
   7596 		    VM_PAGE_TO_PHYS(pg),
   7597 		    md->krw_mappings, md->kro_mappings,
   7598 		    md->urw_mappings, md->uro_mappings);
   7599 
   7600 		SLIST_FOREACH(pv, &md->pvh_list, pv_link) {
   7601 			printf("   %c va 0x%08lx, flags 0x%x\n",
   7602 			    (pm == pv->pv_pmap) ? '*' : ' ',
   7603 			    pv->pv_va, pv->pv_flags);
   7604 		}
   7605 	}
   7606 }
   7607 #endif
   7608 
   7609 #ifdef PMAP_STEAL_MEMORY
   7610 void
   7611 pmap_boot_pageadd(pv_addr_t *newpv)
   7612 {
   7613 	pv_addr_t *pv, *npv;
   7614 
   7615 	if ((pv = SLIST_FIRST(&pmap_boot_freeq)) != NULL) {
   7616 		if (newpv->pv_pa < pv->pv_va) {
   7617 			KASSERT(newpv->pv_pa + newpv->pv_size <= pv->pv_pa);
   7618 			if (newpv->pv_pa + newpv->pv_size == pv->pv_pa) {
   7619 				newpv->pv_size += pv->pv_size;
   7620 				SLIST_REMOVE_HEAD(&pmap_boot_freeq, pv_list);
   7621 			}
   7622 			pv = NULL;
   7623 		} else {
   7624 			for (; (npv = SLIST_NEXT(pv, pv_list)) != NULL;
   7625 			     pv = npv) {
   7626 				KASSERT(pv->pv_pa + pv->pv_size < npv->pv_pa);
   7627 				KASSERT(pv->pv_pa < newpv->pv_pa);
   7628 				if (newpv->pv_pa > npv->pv_pa)
   7629 					continue;
   7630 				if (pv->pv_pa + pv->pv_size == newpv->pv_pa) {
   7631 					pv->pv_size += newpv->pv_size;
   7632 					return;
   7633 				}
   7634 				if (newpv->pv_pa + newpv->pv_size < npv->pv_pa)
   7635 					break;
   7636 				newpv->pv_size += npv->pv_size;
   7637 				SLIST_INSERT_AFTER(pv, newpv, pv_list);
   7638 				SLIST_REMOVE_AFTER(newpv, pv_list);
   7639 				return;
   7640 			}
   7641 		}
   7642 	}
   7643 
   7644 	if (pv) {
   7645 		SLIST_INSERT_AFTER(pv, newpv, pv_list);
   7646 	} else {
   7647 		SLIST_INSERT_HEAD(&pmap_boot_freeq, newpv, pv_list);
   7648 	}
   7649 }
   7650 
   7651 void
   7652 pmap_boot_pagealloc(psize_t amount, psize_t mask, psize_t match,
   7653 	pv_addr_t *rpv)
   7654 {
   7655 	pv_addr_t *pv, **pvp;
   7656 	struct vm_physseg *ps;
   7657 	size_t i;
   7658 
   7659 	KASSERT(amount & PGOFSET);
   7660 	KASSERT((mask & PGOFSET) == 0);
   7661 	KASSERT((match & PGOFSET) == 0);
   7662 	KASSERT(amount != 0);
   7663 
   7664 	for (pvp = &SLIST_FIRST(&pmap_boot_freeq);
   7665 	     (pv = *pvp) != NULL;
   7666 	     pvp = &SLIST_NEXT(pv, pv_list)) {
   7667 		pv_addr_t *newpv;
   7668 		psize_t off;
   7669 		/*
   7670 		 * If this entry is too small to satify the request...
   7671 		 */
   7672 		KASSERT(pv->pv_size > 0);
   7673 		if (pv->pv_size < amount)
   7674 			continue;
   7675 
   7676 		for (off = 0; off <= mask; off += PAGE_SIZE) {
   7677 			if (((pv->pv_pa + off) & mask) == match
   7678 			    && off + amount <= pv->pv_size)
   7679 				break;
   7680 		}
   7681 		if (off > mask)
   7682 			continue;
   7683 
   7684 		rpv->pv_va = pv->pv_va + off;
   7685 		rpv->pv_pa = pv->pv_pa + off;
   7686 		rpv->pv_size = amount;
   7687 		pv->pv_size -= amount;
   7688 		if (pv->pv_size == 0) {
   7689 			KASSERT(off == 0);
   7690 			KASSERT((vaddr_t) pv == rpv->pv_va);
   7691 			*pvp = SLIST_NEXT(pv, pv_list);
   7692 		} else if (off == 0) {
   7693 			KASSERT((vaddr_t) pv == rpv->pv_va);
   7694 			newpv = (pv_addr_t *) (rpv->pv_va + amount);
   7695 			*newpv = *pv;
   7696 			newpv->pv_pa += amount;
   7697 			newpv->pv_va += amount;
   7698 			*pvp = newpv;
   7699 		} else if (off < pv->pv_size) {
   7700 			newpv = (pv_addr_t *) (rpv->pv_va + amount);
   7701 			*newpv = *pv;
   7702 			newpv->pv_size -= off;
   7703 			newpv->pv_pa += off + amount;
   7704 			newpv->pv_va += off + amount;
   7705 
   7706 			SLIST_NEXT(pv, pv_list) = newpv;
   7707 			pv->pv_size = off;
   7708 		} else {
   7709 			KASSERT((vaddr_t) pv != rpv->pv_va);
   7710 		}
   7711 		memset((void *)rpv->pv_va, 0, amount);
   7712 		return;
   7713 	}
   7714 
   7715 	if (vm_nphysseg == 0)
   7716 		panic("pmap_boot_pagealloc: couldn't allocate memory");
   7717 
   7718 	for (pvp = &SLIST_FIRST(&pmap_boot_freeq);
   7719 	     (pv = *pvp) != NULL;
   7720 	     pvp = &SLIST_NEXT(pv, pv_list)) {
   7721 		if (SLIST_NEXT(pv, pv_list) == NULL)
   7722 			break;
   7723 	}
   7724 	KASSERT(mask == 0);
   7725 	for (i = 0; i < vm_nphysseg; i++) {
   7726 		ps = VM_PHYSMEM_PTR(i);
   7727 		if (ps->avail_start == atop(pv->pv_pa + pv->pv_size)
   7728 		    && pv->pv_va + pv->pv_size <= ptoa(ps->avail_end)) {
   7729 			rpv->pv_va = pv->pv_va;
   7730 			rpv->pv_pa = pv->pv_pa;
   7731 			rpv->pv_size = amount;
   7732 			*pvp = NULL;
   7733 			pmap_map_chunk(kernel_l1pt.pv_va,
   7734 			     ptoa(ps->avail_start) + (pv->pv_va - pv->pv_pa),
   7735 			     ptoa(ps->avail_start),
   7736 			     amount - pv->pv_size,
   7737 			     VM_PROT_READ|VM_PROT_WRITE,
   7738 			     PTE_CACHE);
   7739 			ps->avail_start += atop(amount - pv->pv_size);
   7740 			/*
   7741 			 * If we consumed the entire physseg, remove it.
   7742 			 */
   7743 			if (ps->avail_start == ps->avail_end) {
   7744 				for (--vm_nphysseg; i < vm_nphysseg; i++)
   7745 					VM_PHYSMEM_PTR_SWAP(i, i + 1);
   7746 			}
   7747 			memset((void *)rpv->pv_va, 0, rpv->pv_size);
   7748 			return;
   7749 		}
   7750 	}
   7751 
   7752 	panic("pmap_boot_pagealloc: couldn't allocate memory");
   7753 }
   7754 
   7755 vaddr_t
   7756 pmap_steal_memory(vsize_t size, vaddr_t *vstartp, vaddr_t *vendp)
   7757 {
   7758 	pv_addr_t pv;
   7759 
   7760 	pmap_boot_pagealloc(size, 0, 0, &pv);
   7761 
   7762 	return pv.pv_va;
   7763 }
   7764 #endif /* PMAP_STEAL_MEMORY */
   7765 
   7766 SYSCTL_SETUP(sysctl_machdep_pmap_setup, "sysctl machdep.kmpages setup")
   7767 {
   7768 	sysctl_createv(clog, 0, NULL, NULL,
   7769 			CTLFLAG_PERMANENT,
   7770 			CTLTYPE_NODE, "machdep", NULL,
   7771 			NULL, 0, NULL, 0,
   7772 			CTL_MACHDEP, CTL_EOL);
   7773 
   7774 	sysctl_createv(clog, 0, NULL, NULL,
   7775 			CTLFLAG_PERMANENT,
   7776 			CTLTYPE_INT, "kmpages",
   7777 			SYSCTL_DESCR("count of pages allocated to kernel memory allocators"),
   7778 			NULL, 0, &pmap_kmpages, 0,
   7779 			CTL_MACHDEP, CTL_CREATE, CTL_EOL);
   7780 }
   7781 
   7782 #ifdef PMAP_NEED_ALLOC_POOLPAGE
   7783 struct vm_page *
   7784 arm_pmap_alloc_poolpage(int flags)
   7785 {
   7786 	/*
   7787 	 * On some systems, only some pages may be "coherent" for dma and we
   7788 	 * want to prefer those for pool pages (think mbufs) but fallback to
   7789 	 * any page if none is available.  But we can only fallback if we
   7790 	 * aren't direct mapping memory or all of memory can be direct-mapped.
   7791 	 * If that isn't true, pool changes can only come from direct-mapped
   7792 	 * memory.
   7793 	 */
   7794 	if (arm_poolpage_vmfreelist != VM_FREELIST_DEFAULT) {
   7795 		return uvm_pagealloc_strat(NULL, 0, NULL, flags,
   7796 #if defined(__HAVE_MM_MD_DIRECT_MAPPED_PHYS) && defined(ARM_MMU_EXTENDED)
   7797 		    (pmap_directbase < KERNEL_BASE
   7798 			? UVM_PGA_STRAT_ONLY
   7799 			: UVM_PGA_STRAT_FALLBACK),
   7800 #else
   7801 		    UVM_PGA_STRAT_FALLBACK,
   7802 #endif
   7803 		    arm_poolpage_vmfreelist);
   7804 	}
   7805 
   7806 	return uvm_pagealloc(NULL, 0, NULL, flags);
   7807 }
   7808 #endif
   7809 
   7810 #if defined(ARM_MMU_EXTENDED) && defined(MULTIPROCESSOR)
   7811 void
   7812 pmap_md_tlb_info_attach(struct pmap_tlb_info *ti, struct cpu_info *ci)
   7813 {
   7814         /* nothing */
   7815 }
   7816 
   7817 int
   7818 pic_ipi_shootdown(void *arg)
   7819 {
   7820 #if PMAP_NEED_TLB_SHOOTDOWN
   7821 	pmap_tlb_shootdown_process();
   7822 #endif
   7823 	return 1;
   7824 }
   7825 #endif /* ARM_MMU_EXTENDED && MULTIPROCESSOR */
   7826 
   7827 
   7828 #ifdef __HAVE_MM_MD_DIRECT_MAPPED_PHYS
   7829 vaddr_t
   7830 pmap_direct_mapped_phys(paddr_t pa, bool *ok_p, vaddr_t va)
   7831 {
   7832 	bool ok = false;
   7833 	if (physical_start <= pa && pa < physical_end) {
   7834 #ifdef ARM_MMU_EXTENDED
   7835 		const vaddr_t newva = pmap_directbase + pa - physical_start;
   7836 		if (newva >= KERNEL_BASE) {
   7837 			va = newva;
   7838 			ok = true;
   7839 		}
   7840 #else
   7841 		va = KERNEL_BASE + pa - physical_start;
   7842 		ok = true;
   7843 #endif
   7844 	}
   7845 	KASSERT(ok_p);
   7846 	*ok_p = ok;
   7847 	return va;
   7848 }
   7849 
   7850 vaddr_t
   7851 pmap_map_poolpage(paddr_t pa)
   7852 {
   7853 	bool ok __diagused;
   7854 	vaddr_t va = pmap_direct_mapped_phys(pa, &ok, 0);
   7855 	KASSERT(ok);
   7856 #if defined(PMAP_CACHE_VIPT) && !defined(ARM_MMU_EXTENDED)
   7857 	if (arm_cache_prefer_mask != 0) {
   7858 		struct vm_page * const pg = PHYS_TO_VM_PAGE(pa);
   7859 		struct vm_page_md * const md = VM_PAGE_TO_MD(pg);
   7860 		pmap_acquire_page_lock(md);
   7861 		pmap_vac_me_harder(md, pa, pmap_kernel(), va);
   7862 		pmap_release_page_lock(md);
   7863 	}
   7864 #endif
   7865 	return va;
   7866 }
   7867 
   7868 paddr_t
   7869 pmap_unmap_poolpage(vaddr_t va)
   7870 {
   7871 	KASSERT(va >= KERNEL_BASE);
   7872 #if defined(ARM_MMU_EXTENDED)
   7873 	return va - pmap_directbase + physical_start;
   7874 #else
   7875 #ifdef PMAP_CACHE_VIVT
   7876 	cpu_idcache_wbinv_range(va, PAGE_SIZE);
   7877 #endif
   7878         return va - KERNEL_BASE + physical_start;
   7879 #endif
   7880 }
   7881 #endif /* __HAVE_MM_MD_DIRECT_MAPPED_PHYS */
   7882