pmap.c revision 1.37
1 /* $NetBSD: pmap.c,v 1.37 2002/02/05 21:14:36 thorpej Exp $ */ 2 3 /* 4 * Copyright (c) 2002 Wasabi Systems, Inc. 5 * Copyright (c) 2001 Richard Earnshaw 6 * Copyright (c) 2001 Christopher Gilbert 7 * All rights reserved. 8 * 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the company nor the name of the author may be used to 15 * endorse or promote products derived from this software without specific 16 * prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 19 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 20 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 22 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 24 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 /*- 32 * Copyright (c) 1999 The NetBSD Foundation, Inc. 33 * All rights reserved. 34 * 35 * This code is derived from software contributed to The NetBSD Foundation 36 * by Charles M. Hannum. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. All advertising materials mentioning features or use of this software 47 * must display the following acknowledgement: 48 * This product includes software developed by the NetBSD 49 * Foundation, Inc. and its contributors. 50 * 4. Neither the name of The NetBSD Foundation nor the names of its 51 * contributors may be used to endorse or promote products derived 52 * from this software without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 55 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 56 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 57 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 58 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 59 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 60 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 61 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 62 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 63 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 64 * POSSIBILITY OF SUCH DAMAGE. 65 */ 66 67 /* 68 * Copyright (c) 1994-1998 Mark Brinicombe. 69 * Copyright (c) 1994 Brini. 70 * All rights reserved. 71 * 72 * This code is derived from software written for Brini by Mark Brinicombe 73 * 74 * Redistribution and use in source and binary forms, with or without 75 * modification, are permitted provided that the following conditions 76 * are met: 77 * 1. Redistributions of source code must retain the above copyright 78 * notice, this list of conditions and the following disclaimer. 79 * 2. Redistributions in binary form must reproduce the above copyright 80 * notice, this list of conditions and the following disclaimer in the 81 * documentation and/or other materials provided with the distribution. 82 * 3. All advertising materials mentioning features or use of this software 83 * must display the following acknowledgement: 84 * This product includes software developed by Mark Brinicombe. 85 * 4. The name of the author may not be used to endorse or promote products 86 * derived from this software without specific prior written permission. 87 * 88 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 89 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 90 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 91 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 92 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 93 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 94 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 95 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 96 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 97 * 98 * RiscBSD kernel project 99 * 100 * pmap.c 101 * 102 * Machine dependant vm stuff 103 * 104 * Created : 20/09/94 105 */ 106 107 /* 108 * Performance improvements, UVM changes, overhauls and part-rewrites 109 * were contributed by Neil A. Carson <neil (at) causality.com>. 110 */ 111 112 /* 113 * The dram block info is currently referenced from the bootconfig. 114 * This should be placed in a separate structure. 115 */ 116 117 /* 118 * Special compilation symbols 119 * PMAP_DEBUG - Build in pmap_debug_level code 120 */ 121 122 /* Include header files */ 123 124 #include "opt_pmap_debug.h" 125 #include "opt_ddb.h" 126 127 #include <sys/types.h> 128 #include <sys/param.h> 129 #include <sys/kernel.h> 130 #include <sys/systm.h> 131 #include <sys/proc.h> 132 #include <sys/malloc.h> 133 #include <sys/user.h> 134 #include <sys/pool.h> 135 #include <sys/cdefs.h> 136 137 #include <uvm/uvm.h> 138 139 #include <machine/bootconfig.h> 140 #include <machine/bus.h> 141 #include <machine/pmap.h> 142 #include <machine/pcb.h> 143 #include <machine/param.h> 144 #include <arm/arm32/katelib.h> 145 146 __KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.37 2002/02/05 21:14:36 thorpej Exp $"); 147 #ifdef PMAP_DEBUG 148 #define PDEBUG(_lev_,_stat_) \ 149 if (pmap_debug_level >= (_lev_)) \ 150 ((_stat_)) 151 int pmap_debug_level = -2; 152 153 /* 154 * for switching to potentially finer grained debugging 155 */ 156 #define PDB_FOLLOW 0x0001 157 #define PDB_INIT 0x0002 158 #define PDB_ENTER 0x0004 159 #define PDB_REMOVE 0x0008 160 #define PDB_CREATE 0x0010 161 #define PDB_PTPAGE 0x0020 162 #define PDB_ASN 0x0040 163 #define PDB_BITS 0x0080 164 #define PDB_COLLECT 0x0100 165 #define PDB_PROTECT 0x0200 166 #define PDB_BOOTSTRAP 0x1000 167 #define PDB_PARANOIA 0x2000 168 #define PDB_WIRING 0x4000 169 #define PDB_PVDUMP 0x8000 170 171 int debugmap = 0; 172 int pmapdebug = PDB_PARANOIA | PDB_FOLLOW; 173 #define NPDEBUG(_lev_,_stat_) \ 174 if (pmapdebug & (_lev_)) \ 175 ((_stat_)) 176 177 #else /* PMAP_DEBUG */ 178 #define PDEBUG(_lev_,_stat_) /* Nothing */ 179 #define PDEBUG(_lev_,_stat_) /* Nothing */ 180 #endif /* PMAP_DEBUG */ 181 182 struct pmap kernel_pmap_store; 183 184 /* 185 * pool that pmap structures are allocated from 186 */ 187 188 struct pool pmap_pmap_pool; 189 190 pagehook_t page_hook0; 191 pagehook_t page_hook1; 192 char *memhook; 193 pt_entry_t msgbufpte; 194 extern caddr_t msgbufaddr; 195 196 boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */ 197 /* 198 * locking data structures 199 */ 200 201 static struct lock pmap_main_lock; 202 static struct simplelock pvalloc_lock; 203 #ifdef LOCKDEBUG 204 #define PMAP_MAP_TO_HEAD_LOCK() \ 205 (void) spinlockmgr(&pmap_main_lock, LK_SHARED, NULL) 206 #define PMAP_MAP_TO_HEAD_UNLOCK() \ 207 (void) spinlockmgr(&pmap_main_lock, LK_RELEASE, NULL) 208 209 #define PMAP_HEAD_TO_MAP_LOCK() \ 210 (void) spinlockmgr(&pmap_main_lock, LK_EXCLUSIVE, NULL) 211 #define PMAP_HEAD_TO_MAP_UNLOCK() \ 212 (void) spinlockmgr(&pmap_main_lock, LK_RELEASE, NULL) 213 #else 214 #define PMAP_MAP_TO_HEAD_LOCK() /* nothing */ 215 #define PMAP_MAP_TO_HEAD_UNLOCK() /* nothing */ 216 #define PMAP_HEAD_TO_MAP_LOCK() /* nothing */ 217 #define PMAP_HEAD_TO_MAP_UNLOCK() /* nothing */ 218 #endif /* LOCKDEBUG */ 219 220 /* 221 * pv_page management structures: locked by pvalloc_lock 222 */ 223 224 TAILQ_HEAD(pv_pagelist, pv_page); 225 static struct pv_pagelist pv_freepages; /* list of pv_pages with free entrys */ 226 static struct pv_pagelist pv_unusedpgs; /* list of unused pv_pages */ 227 static int pv_nfpvents; /* # of free pv entries */ 228 static struct pv_page *pv_initpage; /* bootstrap page from kernel_map */ 229 static vaddr_t pv_cachedva; /* cached VA for later use */ 230 231 #define PVE_LOWAT (PVE_PER_PVPAGE / 2) /* free pv_entry low water mark */ 232 #define PVE_HIWAT (PVE_LOWAT + (PVE_PER_PVPAGE * 2)) 233 /* high water mark */ 234 235 /* 236 * local prototypes 237 */ 238 239 static struct pv_entry *pmap_add_pvpage __P((struct pv_page *, boolean_t)); 240 static struct pv_entry *pmap_alloc_pv __P((struct pmap *, int)); /* see codes below */ 241 #define ALLOCPV_NEED 0 /* need PV now */ 242 #define ALLOCPV_TRY 1 /* just try to allocate, don't steal */ 243 #define ALLOCPV_NONEED 2 /* don't need PV, just growing cache */ 244 static struct pv_entry *pmap_alloc_pvpage __P((struct pmap *, int)); 245 static void pmap_enter_pv __P((struct vm_page *, 246 struct pv_entry *, struct pmap *, 247 vaddr_t, struct vm_page *, int)); 248 static void pmap_free_pv __P((struct pmap *, struct pv_entry *)); 249 static void pmap_free_pvs __P((struct pmap *, struct pv_entry *)); 250 static void pmap_free_pv_doit __P((struct pv_entry *)); 251 static void pmap_free_pvpage __P((void)); 252 static boolean_t pmap_is_curpmap __P((struct pmap *)); 253 static struct pv_entry *pmap_remove_pv __P((struct vm_page *, struct pmap *, 254 vaddr_t)); 255 #define PMAP_REMOVE_ALL 0 /* remove all mappings */ 256 #define PMAP_REMOVE_SKIPWIRED 1 /* skip wired mappings */ 257 258 static u_int pmap_modify_pv __P((struct pmap *, vaddr_t, struct vm_page *, 259 u_int, u_int)); 260 261 static void pmap_free_l1pt __P((struct l1pt *)); 262 static int pmap_allocpagedir __P((struct pmap *)); 263 static int pmap_clean_page __P((struct pv_entry *, boolean_t)); 264 static void pmap_remove_all __P((struct vm_page *)); 265 266 267 vsize_t npages; 268 269 static struct vm_page *pmap_alloc_ptp __P((struct pmap *, vaddr_t, boolean_t)); 270 static struct vm_page *pmap_get_ptp __P((struct pmap *, vaddr_t, boolean_t)); 271 __inline static void pmap_clearbit __P((struct vm_page *, unsigned int)); 272 __inline static boolean_t pmap_testbit __P((struct vm_page *, unsigned int)); 273 274 extern paddr_t physical_start; 275 extern paddr_t physical_freestart; 276 extern paddr_t physical_end; 277 extern paddr_t physical_freeend; 278 extern unsigned int free_pages; 279 extern int max_processes; 280 281 vaddr_t virtual_start; 282 vaddr_t virtual_end; 283 284 vaddr_t avail_start; 285 vaddr_t avail_end; 286 287 extern pv_addr_t systempage; 288 289 #define ALLOC_PAGE_HOOK(x, s) \ 290 x.va = virtual_start; \ 291 x.pte = (pt_entry_t *)pmap_pte(pmap_kernel(), virtual_start); \ 292 virtual_start += s; 293 294 /* Variables used by the L1 page table queue code */ 295 SIMPLEQ_HEAD(l1pt_queue, l1pt); 296 struct l1pt_queue l1pt_static_queue; /* head of our static l1 queue */ 297 int l1pt_static_queue_count; /* items in the static l1 queue */ 298 int l1pt_static_create_count; /* static l1 items created */ 299 struct l1pt_queue l1pt_queue; /* head of our l1 queue */ 300 int l1pt_queue_count; /* items in the l1 queue */ 301 int l1pt_create_count; /* stat - L1's create count */ 302 int l1pt_reuse_count; /* stat - L1's reused count */ 303 304 /* Local function prototypes (not used outside this file) */ 305 pt_entry_t *pmap_pte __P((struct pmap *pmap, vaddr_t va)); 306 void pmap_copy_on_write __P((struct vm_page *)); 307 void pmap_pinit __P((struct pmap *)); 308 void pmap_freepagedir __P((struct pmap *)); 309 310 /* Other function prototypes */ 311 extern void bzero_page __P((vaddr_t)); 312 extern void bcopy_page __P((vaddr_t, vaddr_t)); 313 314 struct l1pt *pmap_alloc_l1pt __P((void)); 315 static __inline void pmap_map_in_l1 __P((struct pmap *pmap, vaddr_t va, 316 vaddr_t l2pa, boolean_t)); 317 318 static pt_entry_t *pmap_map_ptes __P((struct pmap *)); 319 static void pmap_unmap_ptes __P((struct pmap *)); 320 321 __inline static void pmap_vac_me_harder __P((struct pmap *, struct vm_page *, 322 pt_entry_t *, boolean_t)); 323 static void pmap_vac_me_kpmap __P((struct pmap *, struct vm_page *, 324 pt_entry_t *, boolean_t)); 325 static void pmap_vac_me_user __P((struct pmap *, struct vm_page *, 326 pt_entry_t *, boolean_t)); 327 328 /* 329 * Cache enable bits in PTE to use on pages that are cacheable. 330 * On most machines this is cacheable/bufferable, but on some, eg arm10, we 331 * can chose between write-through and write-back cacheing. 332 */ 333 pt_entry_t pte_cache_mode = (PT_C | PT_B); 334 335 /* 336 * real definition of pv_entry. 337 */ 338 339 struct pv_entry { 340 struct pv_entry *pv_next; /* next pv_entry */ 341 struct pmap *pv_pmap; /* pmap where mapping lies */ 342 vaddr_t pv_va; /* virtual address for mapping */ 343 int pv_flags; /* flags */ 344 struct vm_page *pv_ptp; /* vm_page for the ptp */ 345 }; 346 347 /* 348 * pv_entrys are dynamically allocated in chunks from a single page. 349 * we keep track of how many pv_entrys are in use for each page and 350 * we can free pv_entry pages if needed. there is one lock for the 351 * entire allocation system. 352 */ 353 354 struct pv_page_info { 355 TAILQ_ENTRY(pv_page) pvpi_list; 356 struct pv_entry *pvpi_pvfree; 357 int pvpi_nfree; 358 }; 359 360 /* 361 * number of pv_entry's in a pv_page 362 * (note: won't work on systems where NPBG isn't a constant) 363 */ 364 365 #define PVE_PER_PVPAGE ((NBPG - sizeof(struct pv_page_info)) / \ 366 sizeof(struct pv_entry)) 367 368 /* 369 * a pv_page: where pv_entrys are allocated from 370 */ 371 372 struct pv_page { 373 struct pv_page_info pvinfo; 374 struct pv_entry pvents[PVE_PER_PVPAGE]; 375 }; 376 377 #ifdef MYCROFT_HACK 378 int mycroft_hack = 0; 379 #endif 380 381 /* Function to set the debug level of the pmap code */ 382 383 #ifdef PMAP_DEBUG 384 void 385 pmap_debug(level) 386 int level; 387 { 388 pmap_debug_level = level; 389 printf("pmap_debug: level=%d\n", pmap_debug_level); 390 } 391 #endif /* PMAP_DEBUG */ 392 393 __inline static boolean_t 394 pmap_is_curpmap(struct pmap *pmap) 395 { 396 if ((curproc && curproc->p_vmspace->vm_map.pmap == pmap) 397 || (pmap == pmap_kernel())) 398 return (TRUE); 399 return (FALSE); 400 } 401 #include "isadma.h" 402 403 #if NISADMA > 0 404 /* 405 * Used to protect memory for ISA DMA bounce buffers. If, when loading 406 * pages into the system, memory intersects with any of these ranges, 407 * the intersecting memory will be loaded into a lower-priority free list. 408 */ 409 bus_dma_segment_t *pmap_isa_dma_ranges; 410 int pmap_isa_dma_nranges; 411 412 boolean_t pmap_isa_dma_range_intersect __P((paddr_t, psize_t, 413 paddr_t *, psize_t *)); 414 415 /* 416 * Check if a memory range intersects with an ISA DMA range, and 417 * return the page-rounded intersection if it does. The intersection 418 * will be placed on a lower-priority free list. 419 */ 420 boolean_t 421 pmap_isa_dma_range_intersect(pa, size, pap, sizep) 422 paddr_t pa; 423 psize_t size; 424 paddr_t *pap; 425 psize_t *sizep; 426 { 427 bus_dma_segment_t *ds; 428 int i; 429 430 if (pmap_isa_dma_ranges == NULL) 431 return (FALSE); 432 433 for (i = 0, ds = pmap_isa_dma_ranges; 434 i < pmap_isa_dma_nranges; i++, ds++) { 435 if (ds->ds_addr <= pa && pa < (ds->ds_addr + ds->ds_len)) { 436 /* 437 * Beginning of region intersects with this range. 438 */ 439 *pap = trunc_page(pa); 440 *sizep = round_page(min(pa + size, 441 ds->ds_addr + ds->ds_len) - pa); 442 return (TRUE); 443 } 444 if (pa < ds->ds_addr && ds->ds_addr < (pa + size)) { 445 /* 446 * End of region intersects with this range. 447 */ 448 *pap = trunc_page(ds->ds_addr); 449 *sizep = round_page(min((pa + size) - ds->ds_addr, 450 ds->ds_len)); 451 return (TRUE); 452 } 453 } 454 455 /* 456 * No intersection found. 457 */ 458 return (FALSE); 459 } 460 #endif /* NISADMA > 0 */ 461 462 /* 463 * p v _ e n t r y f u n c t i o n s 464 */ 465 466 /* 467 * pv_entry allocation functions: 468 * the main pv_entry allocation functions are: 469 * pmap_alloc_pv: allocate a pv_entry structure 470 * pmap_free_pv: free one pv_entry 471 * pmap_free_pvs: free a list of pv_entrys 472 * 473 * the rest are helper functions 474 */ 475 476 /* 477 * pmap_alloc_pv: inline function to allocate a pv_entry structure 478 * => we lock pvalloc_lock 479 * => if we fail, we call out to pmap_alloc_pvpage 480 * => 3 modes: 481 * ALLOCPV_NEED = we really need a pv_entry, even if we have to steal it 482 * ALLOCPV_TRY = we want a pv_entry, but not enough to steal 483 * ALLOCPV_NONEED = we are trying to grow our free list, don't really need 484 * one now 485 * 486 * "try" is for optional functions like pmap_copy(). 487 */ 488 489 __inline static struct pv_entry * 490 pmap_alloc_pv(pmap, mode) 491 struct pmap *pmap; 492 int mode; 493 { 494 struct pv_page *pvpage; 495 struct pv_entry *pv; 496 497 simple_lock(&pvalloc_lock); 498 499 if (pv_freepages.tqh_first != NULL) { 500 pvpage = pv_freepages.tqh_first; 501 pvpage->pvinfo.pvpi_nfree--; 502 if (pvpage->pvinfo.pvpi_nfree == 0) { 503 /* nothing left in this one? */ 504 TAILQ_REMOVE(&pv_freepages, pvpage, pvinfo.pvpi_list); 505 } 506 pv = pvpage->pvinfo.pvpi_pvfree; 507 #ifdef DIAGNOSTIC 508 if (pv == NULL) 509 panic("pmap_alloc_pv: pvpi_nfree off"); 510 #endif 511 pvpage->pvinfo.pvpi_pvfree = pv->pv_next; 512 pv_nfpvents--; /* took one from pool */ 513 } else { 514 pv = NULL; /* need more of them */ 515 } 516 517 /* 518 * if below low water mark or we didn't get a pv_entry we try and 519 * create more pv_entrys ... 520 */ 521 522 if (pv_nfpvents < PVE_LOWAT || pv == NULL) { 523 if (pv == NULL) 524 pv = pmap_alloc_pvpage(pmap, (mode == ALLOCPV_TRY) ? 525 mode : ALLOCPV_NEED); 526 else 527 (void) pmap_alloc_pvpage(pmap, ALLOCPV_NONEED); 528 } 529 530 simple_unlock(&pvalloc_lock); 531 return(pv); 532 } 533 534 /* 535 * pmap_alloc_pvpage: maybe allocate a new pvpage 536 * 537 * if need_entry is false: try and allocate a new pv_page 538 * if need_entry is true: try and allocate a new pv_page and return a 539 * new pv_entry from it. if we are unable to allocate a pv_page 540 * we make a last ditch effort to steal a pv_page from some other 541 * mapping. if that fails, we panic... 542 * 543 * => we assume that the caller holds pvalloc_lock 544 */ 545 546 static struct pv_entry * 547 pmap_alloc_pvpage(pmap, mode) 548 struct pmap *pmap; 549 int mode; 550 { 551 struct vm_page *pg; 552 struct pv_page *pvpage; 553 struct pv_entry *pv; 554 int s; 555 556 /* 557 * if we need_entry and we've got unused pv_pages, allocate from there 558 */ 559 560 if (mode != ALLOCPV_NONEED && pv_unusedpgs.tqh_first != NULL) { 561 562 /* move it to pv_freepages list */ 563 pvpage = pv_unusedpgs.tqh_first; 564 TAILQ_REMOVE(&pv_unusedpgs, pvpage, pvinfo.pvpi_list); 565 TAILQ_INSERT_HEAD(&pv_freepages, pvpage, pvinfo.pvpi_list); 566 567 /* allocate a pv_entry */ 568 pvpage->pvinfo.pvpi_nfree--; /* can't go to zero */ 569 pv = pvpage->pvinfo.pvpi_pvfree; 570 #ifdef DIAGNOSTIC 571 if (pv == NULL) 572 panic("pmap_alloc_pvpage: pvpi_nfree off"); 573 #endif 574 pvpage->pvinfo.pvpi_pvfree = pv->pv_next; 575 576 pv_nfpvents--; /* took one from pool */ 577 return(pv); 578 } 579 580 /* 581 * see if we've got a cached unmapped VA that we can map a page in. 582 * if not, try to allocate one. 583 */ 584 585 586 if (pv_cachedva == 0) { 587 s = splvm(); 588 pv_cachedva = uvm_km_kmemalloc(kmem_map, NULL, 589 PAGE_SIZE, UVM_KMF_TRYLOCK|UVM_KMF_VALLOC); 590 splx(s); 591 if (pv_cachedva == 0) { 592 return (NULL); 593 } 594 } 595 596 pg = uvm_pagealloc(NULL, pv_cachedva - vm_map_min(kernel_map), NULL, 597 UVM_PGA_USERESERVE); 598 if (pg) 599 pg->flags &= ~PG_BUSY; /* never busy */ 600 601 if (pg == NULL) 602 return (NULL); 603 604 /* 605 * add a mapping for our new pv_page and free its entrys (save one!) 606 * 607 * NOTE: If we are allocating a PV page for the kernel pmap, the 608 * pmap is already locked! (...but entering the mapping is safe...) 609 */ 610 611 pmap_kenter_pa(pv_cachedva, VM_PAGE_TO_PHYS(pg), VM_PROT_ALL); 612 pmap_update(pmap_kernel()); 613 pvpage = (struct pv_page *) pv_cachedva; 614 pv_cachedva = 0; 615 return (pmap_add_pvpage(pvpage, mode != ALLOCPV_NONEED)); 616 } 617 618 /* 619 * pmap_add_pvpage: add a pv_page's pv_entrys to the free list 620 * 621 * => caller must hold pvalloc_lock 622 * => if need_entry is true, we allocate and return one pv_entry 623 */ 624 625 static struct pv_entry * 626 pmap_add_pvpage(pvp, need_entry) 627 struct pv_page *pvp; 628 boolean_t need_entry; 629 { 630 int tofree, lcv; 631 632 /* do we need to return one? */ 633 tofree = (need_entry) ? PVE_PER_PVPAGE - 1 : PVE_PER_PVPAGE; 634 635 pvp->pvinfo.pvpi_pvfree = NULL; 636 pvp->pvinfo.pvpi_nfree = tofree; 637 for (lcv = 0 ; lcv < tofree ; lcv++) { 638 pvp->pvents[lcv].pv_next = pvp->pvinfo.pvpi_pvfree; 639 pvp->pvinfo.pvpi_pvfree = &pvp->pvents[lcv]; 640 } 641 if (need_entry) 642 TAILQ_INSERT_TAIL(&pv_freepages, pvp, pvinfo.pvpi_list); 643 else 644 TAILQ_INSERT_TAIL(&pv_unusedpgs, pvp, pvinfo.pvpi_list); 645 pv_nfpvents += tofree; 646 return((need_entry) ? &pvp->pvents[lcv] : NULL); 647 } 648 649 /* 650 * pmap_free_pv_doit: actually free a pv_entry 651 * 652 * => do not call this directly! instead use either 653 * 1. pmap_free_pv ==> free a single pv_entry 654 * 2. pmap_free_pvs => free a list of pv_entrys 655 * => we must be holding pvalloc_lock 656 */ 657 658 __inline static void 659 pmap_free_pv_doit(pv) 660 struct pv_entry *pv; 661 { 662 struct pv_page *pvp; 663 664 pvp = (struct pv_page *) arm_trunc_page((vaddr_t)pv); 665 pv_nfpvents++; 666 pvp->pvinfo.pvpi_nfree++; 667 668 /* nfree == 1 => fully allocated page just became partly allocated */ 669 if (pvp->pvinfo.pvpi_nfree == 1) { 670 TAILQ_INSERT_HEAD(&pv_freepages, pvp, pvinfo.pvpi_list); 671 } 672 673 /* free it */ 674 pv->pv_next = pvp->pvinfo.pvpi_pvfree; 675 pvp->pvinfo.pvpi_pvfree = pv; 676 677 /* 678 * are all pv_page's pv_entry's free? move it to unused queue. 679 */ 680 681 if (pvp->pvinfo.pvpi_nfree == PVE_PER_PVPAGE) { 682 TAILQ_REMOVE(&pv_freepages, pvp, pvinfo.pvpi_list); 683 TAILQ_INSERT_HEAD(&pv_unusedpgs, pvp, pvinfo.pvpi_list); 684 } 685 } 686 687 /* 688 * pmap_free_pv: free a single pv_entry 689 * 690 * => we gain the pvalloc_lock 691 */ 692 693 __inline static void 694 pmap_free_pv(pmap, pv) 695 struct pmap *pmap; 696 struct pv_entry *pv; 697 { 698 simple_lock(&pvalloc_lock); 699 pmap_free_pv_doit(pv); 700 701 /* 702 * Can't free the PV page if the PV entries were associated with 703 * the kernel pmap; the pmap is already locked. 704 */ 705 if (pv_nfpvents > PVE_HIWAT && pv_unusedpgs.tqh_first != NULL && 706 pmap != pmap_kernel()) 707 pmap_free_pvpage(); 708 709 simple_unlock(&pvalloc_lock); 710 } 711 712 /* 713 * pmap_free_pvs: free a list of pv_entrys 714 * 715 * => we gain the pvalloc_lock 716 */ 717 718 __inline static void 719 pmap_free_pvs(pmap, pvs) 720 struct pmap *pmap; 721 struct pv_entry *pvs; 722 { 723 struct pv_entry *nextpv; 724 725 simple_lock(&pvalloc_lock); 726 727 for ( /* null */ ; pvs != NULL ; pvs = nextpv) { 728 nextpv = pvs->pv_next; 729 pmap_free_pv_doit(pvs); 730 } 731 732 /* 733 * Can't free the PV page if the PV entries were associated with 734 * the kernel pmap; the pmap is already locked. 735 */ 736 if (pv_nfpvents > PVE_HIWAT && pv_unusedpgs.tqh_first != NULL && 737 pmap != pmap_kernel()) 738 pmap_free_pvpage(); 739 740 simple_unlock(&pvalloc_lock); 741 } 742 743 744 /* 745 * pmap_free_pvpage: try and free an unused pv_page structure 746 * 747 * => assume caller is holding the pvalloc_lock and that 748 * there is a page on the pv_unusedpgs list 749 * => if we can't get a lock on the kmem_map we try again later 750 * => note: analysis of MI kmem_map usage [i.e. malloc/free] shows 751 * that if we can lock the kmem_map then we are not already 752 * holding kmem_object's lock. 753 */ 754 755 static void 756 pmap_free_pvpage() 757 { 758 int s; 759 struct vm_map *map; 760 struct vm_map_entry *dead_entries; 761 struct pv_page *pvp; 762 763 s = splvm(); /* protect kmem_map */ 764 765 pvp = pv_unusedpgs.tqh_first; 766 767 /* 768 * note: watch out for pv_initpage which is allocated out of 769 * kernel_map rather than kmem_map. 770 */ 771 if (pvp == pv_initpage) 772 map = kernel_map; 773 else 774 map = kmem_map; 775 776 if (vm_map_lock_try(map)) { 777 778 /* remove pvp from pv_unusedpgs */ 779 TAILQ_REMOVE(&pv_unusedpgs, pvp, pvinfo.pvpi_list); 780 781 /* unmap the page */ 782 dead_entries = NULL; 783 uvm_unmap_remove(map, (vaddr_t)pvp, ((vaddr_t)pvp) + PAGE_SIZE, 784 &dead_entries); 785 vm_map_unlock(map); 786 787 if (dead_entries != NULL) 788 uvm_unmap_detach(dead_entries, 0); 789 790 pv_nfpvents -= PVE_PER_PVPAGE; /* update free count */ 791 } 792 793 if (pvp == pv_initpage) 794 /* no more initpage, we've freed it */ 795 pv_initpage = NULL; 796 797 splx(s); 798 } 799 800 /* 801 * main pv_entry manipulation functions: 802 * pmap_enter_pv: enter a mapping onto a vm_page list 803 * pmap_remove_pv: remove a mappiing from a vm_page list 804 * 805 * NOTE: pmap_enter_pv expects to lock the pvh itself 806 * pmap_remove_pv expects te caller to lock the pvh before calling 807 */ 808 809 /* 810 * pmap_enter_pv: enter a mapping onto a vm_page lst 811 * 812 * => caller should hold the proper lock on pmap_main_lock 813 * => caller should have pmap locked 814 * => we will gain the lock on the vm_page and allocate the new pv_entry 815 * => caller should adjust ptp's wire_count before calling 816 * => caller should not adjust pmap's wire_count 817 */ 818 819 __inline static void 820 pmap_enter_pv(pg, pve, pmap, va, ptp, flags) 821 struct vm_page *pg; 822 struct pv_entry *pve; /* preallocated pve for us to use */ 823 struct pmap *pmap; 824 vaddr_t va; 825 struct vm_page *ptp; /* PTP in pmap that maps this VA */ 826 int flags; 827 { 828 pve->pv_pmap = pmap; 829 pve->pv_va = va; 830 pve->pv_ptp = ptp; /* NULL for kernel pmap */ 831 pve->pv_flags = flags; 832 simple_lock(&pg->mdpage.pvh_slock); /* lock vm_page */ 833 pve->pv_next = pg->mdpage.pvh_list; /* add to ... */ 834 pg->mdpage.pvh_list = pve; /* ... locked list */ 835 simple_unlock(&pg->mdpage.pvh_slock); /* unlock, done! */ 836 if (pve->pv_flags & PT_W) 837 ++pmap->pm_stats.wired_count; 838 } 839 840 /* 841 * pmap_remove_pv: try to remove a mapping from a pv_list 842 * 843 * => caller should hold proper lock on pmap_main_lock 844 * => pmap should be locked 845 * => caller should hold lock on vm_page [so that attrs can be adjusted] 846 * => caller should adjust ptp's wire_count and free PTP if needed 847 * => caller should NOT adjust pmap's wire_count 848 * => we return the removed pve 849 */ 850 851 __inline static struct pv_entry * 852 pmap_remove_pv(pg, pmap, va) 853 struct vm_page *pg; 854 struct pmap *pmap; 855 vaddr_t va; 856 { 857 struct pv_entry *pve, **prevptr; 858 859 prevptr = &pg->mdpage.pvh_list; /* previous pv_entry pointer */ 860 pve = *prevptr; 861 while (pve) { 862 if (pve->pv_pmap == pmap && pve->pv_va == va) { /* match? */ 863 *prevptr = pve->pv_next; /* remove it! */ 864 if (pve->pv_flags & PT_W) 865 --pmap->pm_stats.wired_count; 866 break; 867 } 868 prevptr = &pve->pv_next; /* previous pointer */ 869 pve = pve->pv_next; /* advance */ 870 } 871 return(pve); /* return removed pve */ 872 } 873 874 /* 875 * 876 * pmap_modify_pv: Update pv flags 877 * 878 * => caller should hold lock on vm_page [so that attrs can be adjusted] 879 * => caller should NOT adjust pmap's wire_count 880 * => caller must call pmap_vac_me_harder() if writable status of a page 881 * may have changed. 882 * => we return the old flags 883 * 884 * Modify a physical-virtual mapping in the pv table 885 */ 886 887 /*__inline */ 888 static u_int 889 pmap_modify_pv(pmap, va, pg, bic_mask, eor_mask) 890 struct pmap *pmap; 891 vaddr_t va; 892 struct vm_page *pg; 893 u_int bic_mask; 894 u_int eor_mask; 895 { 896 struct pv_entry *npv; 897 u_int flags, oflags; 898 899 /* 900 * There is at least one VA mapping this page. 901 */ 902 903 for (npv = pg->mdpage.pvh_list; npv; npv = npv->pv_next) { 904 if (pmap == npv->pv_pmap && va == npv->pv_va) { 905 oflags = npv->pv_flags; 906 npv->pv_flags = flags = 907 ((oflags & ~bic_mask) ^ eor_mask); 908 if ((flags ^ oflags) & PT_W) { 909 if (flags & PT_W) 910 ++pmap->pm_stats.wired_count; 911 else 912 --pmap->pm_stats.wired_count; 913 } 914 return (oflags); 915 } 916 } 917 return (0); 918 } 919 920 /* 921 * Map the specified level 2 pagetable into the level 1 page table for 922 * the given pmap to cover a chunk of virtual address space starting from the 923 * address specified. 924 */ 925 static /*__inline*/ void 926 pmap_map_in_l1(pmap, va, l2pa, selfref) 927 struct pmap *pmap; 928 vaddr_t va, l2pa; 929 boolean_t selfref; 930 { 931 vaddr_t ptva; 932 933 /* Calculate the index into the L1 page table. */ 934 ptva = (va >> PDSHIFT) & ~3; 935 936 PDEBUG(0, printf("wiring %08lx in to pd%p pte0x%lx va0x%lx\n", l2pa, 937 pmap->pm_pdir, L1_PTE(l2pa), ptva)); 938 939 /* Map page table into the L1. */ 940 pmap->pm_pdir[ptva + 0] = L1_PTE(l2pa + 0x000); 941 pmap->pm_pdir[ptva + 1] = L1_PTE(l2pa + 0x400); 942 pmap->pm_pdir[ptva + 2] = L1_PTE(l2pa + 0x800); 943 pmap->pm_pdir[ptva + 3] = L1_PTE(l2pa + 0xc00); 944 945 PDEBUG(0, printf("pt self reference %lx in %lx\n", 946 L2_PTE_NC_NB(l2pa, AP_KRW), pmap->pm_vptpt)); 947 948 /* Map the page table into the page table area. */ 949 if (selfref) { 950 *((pt_entry_t *)(pmap->pm_vptpt + ptva)) = 951 L2_PTE_NC_NB(l2pa, AP_KRW); 952 } 953 /* XXX should be a purge */ 954 /* cpu_tlb_flushD();*/ 955 } 956 957 #if 0 958 static /*__inline*/ void 959 pmap_unmap_in_l1(pmap, va) 960 struct pmap *pmap; 961 vaddr_t va; 962 { 963 vaddr_t ptva; 964 965 /* Calculate the index into the L1 page table. */ 966 ptva = (va >> PDSHIFT) & ~3; 967 968 /* Unmap page table from the L1. */ 969 pmap->pm_pdir[ptva + 0] = 0; 970 pmap->pm_pdir[ptva + 1] = 0; 971 pmap->pm_pdir[ptva + 2] = 0; 972 pmap->pm_pdir[ptva + 3] = 0; 973 974 /* Unmap the page table from the page table area. */ 975 *((pt_entry_t *)(pmap->pm_vptpt + ptva)) = 0; 976 977 /* XXX should be a purge */ 978 /* cpu_tlb_flushD();*/ 979 } 980 #endif 981 982 /* 983 * Used to map a range of physical addresses into kernel 984 * virtual address space. 985 * 986 * For now, VM is already on, we only need to map the 987 * specified memory. 988 */ 989 vaddr_t 990 pmap_map(va, spa, epa, prot) 991 vaddr_t va, spa, epa; 992 int prot; 993 { 994 while (spa < epa) { 995 pmap_kenter_pa(va, spa, prot); 996 va += NBPG; 997 spa += NBPG; 998 } 999 pmap_update(pmap_kernel()); 1000 return(va); 1001 } 1002 1003 1004 /* 1005 * void pmap_bootstrap(pd_entry_t *kernel_l1pt, pv_addr_t kernel_ptpt) 1006 * 1007 * bootstrap the pmap system. This is called from initarm and allows 1008 * the pmap system to initailise any structures it requires. 1009 * 1010 * Currently this sets up the kernel_pmap that is statically allocated 1011 * and also allocated virtual addresses for certain page hooks. 1012 * Currently the only one page hook is allocated that is used 1013 * to zero physical pages of memory. 1014 * It also initialises the start and end address of the kernel data space. 1015 */ 1016 extern paddr_t physical_freestart; 1017 extern paddr_t physical_freeend; 1018 1019 char *boot_head; 1020 1021 void 1022 pmap_bootstrap(kernel_l1pt, kernel_ptpt) 1023 pd_entry_t *kernel_l1pt; 1024 pv_addr_t kernel_ptpt; 1025 { 1026 int loop; 1027 paddr_t start, end; 1028 #if NISADMA > 0 1029 paddr_t istart; 1030 psize_t isize; 1031 #endif 1032 1033 pmap_kernel()->pm_pdir = kernel_l1pt; 1034 pmap_kernel()->pm_pptpt = kernel_ptpt.pv_pa; 1035 pmap_kernel()->pm_vptpt = kernel_ptpt.pv_va; 1036 simple_lock_init(&pmap_kernel()->pm_lock); 1037 pmap_kernel()->pm_obj.pgops = NULL; 1038 TAILQ_INIT(&(pmap_kernel()->pm_obj.memq)); 1039 pmap_kernel()->pm_obj.uo_npages = 0; 1040 pmap_kernel()->pm_obj.uo_refs = 1; 1041 1042 /* 1043 * Initialize PAGE_SIZE-dependent variables. 1044 */ 1045 uvm_setpagesize(); 1046 1047 npages = 0; 1048 loop = 0; 1049 while (loop < bootconfig.dramblocks) { 1050 start = (paddr_t)bootconfig.dram[loop].address; 1051 end = start + (bootconfig.dram[loop].pages * NBPG); 1052 if (start < physical_freestart) 1053 start = physical_freestart; 1054 if (end > physical_freeend) 1055 end = physical_freeend; 1056 #if 0 1057 printf("%d: %lx -> %lx\n", loop, start, end - 1); 1058 #endif 1059 #if NISADMA > 0 1060 if (pmap_isa_dma_range_intersect(start, end - start, 1061 &istart, &isize)) { 1062 /* 1063 * Place the pages that intersect with the 1064 * ISA DMA range onto the ISA DMA free list. 1065 */ 1066 #if 0 1067 printf(" ISADMA 0x%lx -> 0x%lx\n", istart, 1068 istart + isize - 1); 1069 #endif 1070 uvm_page_physload(atop(istart), 1071 atop(istart + isize), atop(istart), 1072 atop(istart + isize), VM_FREELIST_ISADMA); 1073 npages += atop(istart + isize) - atop(istart); 1074 1075 /* 1076 * Load the pieces that come before 1077 * the intersection into the default 1078 * free list. 1079 */ 1080 if (start < istart) { 1081 #if 0 1082 printf(" BEFORE 0x%lx -> 0x%lx\n", 1083 start, istart - 1); 1084 #endif 1085 uvm_page_physload(atop(start), 1086 atop(istart), atop(start), 1087 atop(istart), VM_FREELIST_DEFAULT); 1088 npages += atop(istart) - atop(start); 1089 } 1090 1091 /* 1092 * Load the pieces that come after 1093 * the intersection into the default 1094 * free list. 1095 */ 1096 if ((istart + isize) < end) { 1097 #if 0 1098 printf(" AFTER 0x%lx -> 0x%lx\n", 1099 (istart + isize), end - 1); 1100 #endif 1101 uvm_page_physload(atop(istart + isize), 1102 atop(end), atop(istart + isize), 1103 atop(end), VM_FREELIST_DEFAULT); 1104 npages += atop(end) - atop(istart + isize); 1105 } 1106 } else { 1107 uvm_page_physload(atop(start), atop(end), 1108 atop(start), atop(end), VM_FREELIST_DEFAULT); 1109 npages += atop(end) - atop(start); 1110 } 1111 #else /* NISADMA > 0 */ 1112 uvm_page_physload(atop(start), atop(end), 1113 atop(start), atop(end), VM_FREELIST_DEFAULT); 1114 npages += atop(end) - atop(start); 1115 #endif /* NISADMA > 0 */ 1116 ++loop; 1117 } 1118 1119 #ifdef MYCROFT_HACK 1120 printf("npages = %ld\n", npages); 1121 #endif 1122 1123 virtual_start = KERNEL_VM_BASE; 1124 virtual_end = virtual_start + KERNEL_VM_SIZE - 1; 1125 1126 ALLOC_PAGE_HOOK(page_hook0, NBPG); 1127 ALLOC_PAGE_HOOK(page_hook1, NBPG); 1128 1129 /* 1130 * The mem special device needs a virtual hook but we don't 1131 * need a pte 1132 */ 1133 memhook = (char *)virtual_start; 1134 virtual_start += NBPG; 1135 1136 msgbufaddr = (caddr_t)virtual_start; 1137 msgbufpte = (pt_entry_t)pmap_pte(pmap_kernel(), virtual_start); 1138 virtual_start += round_page(MSGBUFSIZE); 1139 1140 /* 1141 * init the static-global locks and global lists. 1142 */ 1143 spinlockinit(&pmap_main_lock, "pmaplk", 0); 1144 simple_lock_init(&pvalloc_lock); 1145 TAILQ_INIT(&pv_freepages); 1146 TAILQ_INIT(&pv_unusedpgs); 1147 1148 /* 1149 * initialize the pmap pool. 1150 */ 1151 1152 pool_init(&pmap_pmap_pool, sizeof(struct pmap), 0, 0, 0, "pmappl", 1153 0, pool_page_alloc_nointr, pool_page_free_nointr, M_VMPMAP); 1154 1155 cpu_dcache_wbinv_all(); 1156 } 1157 1158 /* 1159 * void pmap_init(void) 1160 * 1161 * Initialize the pmap module. 1162 * Called by vm_init() in vm/vm_init.c in order to initialise 1163 * any structures that the pmap system needs to map virtual memory. 1164 */ 1165 1166 extern int physmem; 1167 1168 void 1169 pmap_init() 1170 { 1171 1172 /* 1173 * Set the available memory vars - These do not map to real memory 1174 * addresses and cannot as the physical memory is fragmented. 1175 * They are used by ps for %mem calculations. 1176 * One could argue whether this should be the entire memory or just 1177 * the memory that is useable in a user process. 1178 */ 1179 avail_start = 0; 1180 avail_end = physmem * NBPG; 1181 1182 /* 1183 * now we need to free enough pv_entry structures to allow us to get 1184 * the kmem_map/kmem_object allocated and inited (done after this 1185 * function is finished). to do this we allocate one bootstrap page out 1186 * of kernel_map and use it to provide an initial pool of pv_entry 1187 * structures. we never free this page. 1188 */ 1189 1190 pv_initpage = (struct pv_page *) uvm_km_alloc(kernel_map, PAGE_SIZE); 1191 if (pv_initpage == NULL) 1192 panic("pmap_init: pv_initpage"); 1193 pv_cachedva = 0; /* a VA we have allocated but not used yet */ 1194 pv_nfpvents = 0; 1195 (void) pmap_add_pvpage(pv_initpage, FALSE); 1196 1197 pmap_initialized = TRUE; 1198 1199 /* Initialise our L1 page table queues and counters */ 1200 SIMPLEQ_INIT(&l1pt_static_queue); 1201 l1pt_static_queue_count = 0; 1202 l1pt_static_create_count = 0; 1203 SIMPLEQ_INIT(&l1pt_queue); 1204 l1pt_queue_count = 0; 1205 l1pt_create_count = 0; 1206 l1pt_reuse_count = 0; 1207 } 1208 1209 /* 1210 * pmap_postinit() 1211 * 1212 * This routine is called after the vm and kmem subsystems have been 1213 * initialised. This allows the pmap code to perform any initialisation 1214 * that can only be done one the memory allocation is in place. 1215 */ 1216 1217 void 1218 pmap_postinit() 1219 { 1220 int loop; 1221 struct l1pt *pt; 1222 1223 #ifdef PMAP_STATIC_L1S 1224 for (loop = 0; loop < PMAP_STATIC_L1S; ++loop) { 1225 #else /* PMAP_STATIC_L1S */ 1226 for (loop = 0; loop < max_processes; ++loop) { 1227 #endif /* PMAP_STATIC_L1S */ 1228 /* Allocate a L1 page table */ 1229 pt = pmap_alloc_l1pt(); 1230 if (!pt) 1231 panic("Cannot allocate static L1 page tables\n"); 1232 1233 /* Clean it */ 1234 bzero((void *)pt->pt_va, PD_SIZE); 1235 pt->pt_flags |= (PTFLAG_STATIC | PTFLAG_CLEAN); 1236 /* Add the page table to the queue */ 1237 SIMPLEQ_INSERT_TAIL(&l1pt_static_queue, pt, pt_queue); 1238 ++l1pt_static_queue_count; 1239 ++l1pt_static_create_count; 1240 } 1241 } 1242 1243 1244 /* 1245 * Create and return a physical map. 1246 * 1247 * If the size specified for the map is zero, the map is an actual physical 1248 * map, and may be referenced by the hardware. 1249 * 1250 * If the size specified is non-zero, the map will be used in software only, 1251 * and is bounded by that size. 1252 */ 1253 1254 pmap_t 1255 pmap_create() 1256 { 1257 struct pmap *pmap; 1258 1259 /* 1260 * Fetch pmap entry from the pool 1261 */ 1262 1263 pmap = pool_get(&pmap_pmap_pool, PR_WAITOK); 1264 /* XXX is this really needed! */ 1265 memset(pmap, 0, sizeof(*pmap)); 1266 1267 simple_lock_init(&pmap->pm_obj.vmobjlock); 1268 pmap->pm_obj.pgops = NULL; /* currently not a mappable object */ 1269 TAILQ_INIT(&pmap->pm_obj.memq); 1270 pmap->pm_obj.uo_npages = 0; 1271 pmap->pm_obj.uo_refs = 1; 1272 pmap->pm_stats.wired_count = 0; 1273 pmap->pm_stats.resident_count = 1; 1274 1275 /* Now init the machine part of the pmap */ 1276 pmap_pinit(pmap); 1277 return(pmap); 1278 } 1279 1280 /* 1281 * pmap_alloc_l1pt() 1282 * 1283 * This routine allocates physical and virtual memory for a L1 page table 1284 * and wires it. 1285 * A l1pt structure is returned to describe the allocated page table. 1286 * 1287 * This routine is allowed to fail if the required memory cannot be allocated. 1288 * In this case NULL is returned. 1289 */ 1290 1291 struct l1pt * 1292 pmap_alloc_l1pt(void) 1293 { 1294 paddr_t pa; 1295 vaddr_t va; 1296 struct l1pt *pt; 1297 int error; 1298 struct vm_page *m; 1299 pt_entry_t *ptes; 1300 1301 /* Allocate virtual address space for the L1 page table */ 1302 va = uvm_km_valloc(kernel_map, PD_SIZE); 1303 if (va == 0) { 1304 #ifdef DIAGNOSTIC 1305 PDEBUG(0, 1306 printf("pmap: Cannot allocate pageable memory for L1\n")); 1307 #endif /* DIAGNOSTIC */ 1308 return(NULL); 1309 } 1310 1311 /* Allocate memory for the l1pt structure */ 1312 pt = (struct l1pt *)malloc(sizeof(struct l1pt), M_VMPMAP, M_WAITOK); 1313 1314 /* 1315 * Allocate pages from the VM system. 1316 */ 1317 TAILQ_INIT(&pt->pt_plist); 1318 error = uvm_pglistalloc(PD_SIZE, physical_start, physical_end, 1319 PD_SIZE, 0, &pt->pt_plist, 1, M_WAITOK); 1320 if (error) { 1321 #ifdef DIAGNOSTIC 1322 PDEBUG(0, 1323 printf("pmap: Cannot allocate physical mem for L1 (%d)\n", 1324 error)); 1325 #endif /* DIAGNOSTIC */ 1326 /* Release the resources we already have claimed */ 1327 free(pt, M_VMPMAP); 1328 uvm_km_free(kernel_map, va, PD_SIZE); 1329 return(NULL); 1330 } 1331 1332 /* Map our physical pages into our virtual space */ 1333 pt->pt_va = va; 1334 m = pt->pt_plist.tqh_first; 1335 ptes = pmap_map_ptes(pmap_kernel()); 1336 while (m && va < (pt->pt_va + PD_SIZE)) { 1337 pa = VM_PAGE_TO_PHYS(m); 1338 1339 pmap_kenter_pa(va, pa, VM_PROT_READ | VM_PROT_WRITE); 1340 1341 /* Revoke cacheability and bufferability */ 1342 /* XXX should be done better than this */ 1343 ptes[arm_byte_to_page(va)] &= ~(PT_C | PT_B); 1344 1345 va += NBPG; 1346 m = m->pageq.tqe_next; 1347 } 1348 pmap_unmap_ptes(pmap_kernel()); 1349 pmap_update(pmap_kernel()); 1350 1351 #ifdef DIAGNOSTIC 1352 if (m) 1353 panic("pmap_alloc_l1pt: pglist not empty\n"); 1354 #endif /* DIAGNOSTIC */ 1355 1356 pt->pt_flags = 0; 1357 return(pt); 1358 } 1359 1360 /* 1361 * Free a L1 page table previously allocated with pmap_alloc_l1pt(). 1362 */ 1363 static void 1364 pmap_free_l1pt(pt) 1365 struct l1pt *pt; 1366 { 1367 /* Separate the physical memory for the virtual space */ 1368 pmap_kremove(pt->pt_va, PD_SIZE); 1369 pmap_update(pmap_kernel()); 1370 1371 /* Return the physical memory */ 1372 uvm_pglistfree(&pt->pt_plist); 1373 1374 /* Free the virtual space */ 1375 uvm_km_free(kernel_map, pt->pt_va, PD_SIZE); 1376 1377 /* Free the l1pt structure */ 1378 free(pt, M_VMPMAP); 1379 } 1380 1381 /* 1382 * Allocate a page directory. 1383 * This routine will either allocate a new page directory from the pool 1384 * of L1 page tables currently held by the kernel or it will allocate 1385 * a new one via pmap_alloc_l1pt(). 1386 * It will then initialise the l1 page table for use. 1387 */ 1388 static int 1389 pmap_allocpagedir(pmap) 1390 struct pmap *pmap; 1391 { 1392 paddr_t pa; 1393 struct l1pt *pt; 1394 pt_entry_t *pte; 1395 1396 PDEBUG(0, printf("pmap_allocpagedir(%p)\n", pmap)); 1397 1398 /* Do we have any spare L1's lying around ? */ 1399 if (l1pt_static_queue_count) { 1400 --l1pt_static_queue_count; 1401 pt = l1pt_static_queue.sqh_first; 1402 SIMPLEQ_REMOVE_HEAD(&l1pt_static_queue, pt, pt_queue); 1403 } else if (l1pt_queue_count) { 1404 --l1pt_queue_count; 1405 pt = l1pt_queue.sqh_first; 1406 SIMPLEQ_REMOVE_HEAD(&l1pt_queue, pt, pt_queue); 1407 ++l1pt_reuse_count; 1408 } else { 1409 pt = pmap_alloc_l1pt(); 1410 if (!pt) 1411 return(ENOMEM); 1412 ++l1pt_create_count; 1413 } 1414 1415 /* Store the pointer to the l1 descriptor in the pmap. */ 1416 pmap->pm_l1pt = pt; 1417 1418 /* Get the physical address of the start of the l1 */ 1419 pa = VM_PAGE_TO_PHYS(pt->pt_plist.tqh_first); 1420 1421 /* Store the virtual address of the l1 in the pmap. */ 1422 pmap->pm_pdir = (pd_entry_t *)pt->pt_va; 1423 1424 /* Clean the L1 if it is dirty */ 1425 if (!(pt->pt_flags & PTFLAG_CLEAN)) 1426 bzero((void *)pmap->pm_pdir, (PD_SIZE - KERNEL_PD_SIZE)); 1427 1428 /* Do we already have the kernel mappings ? */ 1429 if (!(pt->pt_flags & PTFLAG_KPT)) { 1430 /* Duplicate the kernel mapping i.e. all mappings 0xf0000000+ */ 1431 1432 bcopy((char *)pmap_kernel()->pm_pdir + (PD_SIZE - KERNEL_PD_SIZE), 1433 (char *)pmap->pm_pdir + (PD_SIZE - KERNEL_PD_SIZE), 1434 KERNEL_PD_SIZE); 1435 pt->pt_flags |= PTFLAG_KPT; 1436 } 1437 1438 /* Allocate a page table to map all the page tables for this pmap */ 1439 1440 #ifdef DIAGNOSTIC 1441 if (pmap->pm_vptpt) { 1442 /* XXX What if we have one already ? */ 1443 panic("pmap_allocpagedir: have pt already\n"); 1444 } 1445 #endif /* DIAGNOSTIC */ 1446 pmap->pm_vptpt = uvm_km_zalloc(kernel_map, NBPG); 1447 if (pmap->pm_vptpt == 0) { 1448 pmap_freepagedir(pmap); 1449 return(ENOMEM); 1450 } 1451 1452 (void) pmap_extract(pmap_kernel(), pmap->pm_vptpt, &pmap->pm_pptpt); 1453 pmap->pm_pptpt &= PG_FRAME; 1454 /* Revoke cacheability and bufferability */ 1455 /* XXX should be done better than this */ 1456 pte = pmap_pte(pmap_kernel(), pmap->pm_vptpt); 1457 *pte = *pte & ~(PT_C | PT_B); 1458 1459 /* Wire in this page table */ 1460 pmap_map_in_l1(pmap, PROCESS_PAGE_TBLS_BASE, pmap->pm_pptpt, TRUE); 1461 1462 pt->pt_flags &= ~PTFLAG_CLEAN; /* L1 is dirty now */ 1463 1464 /* 1465 * Map the kernel page tables for 0xf0000000 + 1466 * into the page table used to map the 1467 * pmap's page tables 1468 */ 1469 bcopy((char *)(PROCESS_PAGE_TBLS_BASE 1470 + (PROCESS_PAGE_TBLS_BASE >> (PGSHIFT - 2)) 1471 + ((PD_SIZE - KERNEL_PD_SIZE) >> 2)), 1472 (char *)pmap->pm_vptpt + ((PD_SIZE - KERNEL_PD_SIZE) >> 2), 1473 (KERNEL_PD_SIZE >> 2)); 1474 1475 return(0); 1476 } 1477 1478 1479 /* 1480 * Initialize a preallocated and zeroed pmap structure, 1481 * such as one in a vmspace structure. 1482 */ 1483 1484 void 1485 pmap_pinit(pmap) 1486 struct pmap *pmap; 1487 { 1488 int backoff = 6; 1489 int retry = 10; 1490 1491 PDEBUG(0, printf("pmap_pinit(%p)\n", pmap)); 1492 1493 /* Keep looping until we succeed in allocating a page directory */ 1494 while (pmap_allocpagedir(pmap) != 0) { 1495 /* 1496 * Ok we failed to allocate a suitable block of memory for an 1497 * L1 page table. This means that either: 1498 * 1. 16KB of virtual address space could not be allocated 1499 * 2. 16KB of physically contiguous memory on a 16KB boundary 1500 * could not be allocated. 1501 * 1502 * Since we cannot fail we will sleep for a while and try 1503 * again. 1504 * 1505 * Searching for a suitable L1 PT is expensive: 1506 * to avoid hogging the system when memory is really 1507 * scarce, use an exponential back-off so that 1508 * eventually we won't retry more than once every 8 1509 * seconds. This should allow other processes to run 1510 * to completion and free up resources. 1511 */ 1512 (void) ltsleep(&lbolt, PVM, "l1ptwait", (hz << 3) >> backoff, 1513 NULL); 1514 if (--retry == 0) { 1515 retry = 10; 1516 if (backoff) 1517 --backoff; 1518 } 1519 } 1520 1521 /* Map zero page for the pmap. This will also map the L2 for it */ 1522 pmap_enter(pmap, 0x00000000, systempage.pv_pa, 1523 VM_PROT_READ, VM_PROT_READ | PMAP_WIRED); 1524 pmap_update(pmap); 1525 } 1526 1527 1528 void 1529 pmap_freepagedir(pmap) 1530 struct pmap *pmap; 1531 { 1532 /* Free the memory used for the page table mapping */ 1533 if (pmap->pm_vptpt != 0) 1534 uvm_km_free(kernel_map, (vaddr_t)pmap->pm_vptpt, NBPG); 1535 1536 /* junk the L1 page table */ 1537 if (pmap->pm_l1pt->pt_flags & PTFLAG_STATIC) { 1538 /* Add the page table to the queue */ 1539 SIMPLEQ_INSERT_TAIL(&l1pt_static_queue, pmap->pm_l1pt, pt_queue); 1540 ++l1pt_static_queue_count; 1541 } else if (l1pt_queue_count < 8) { 1542 /* Add the page table to the queue */ 1543 SIMPLEQ_INSERT_TAIL(&l1pt_queue, pmap->pm_l1pt, pt_queue); 1544 ++l1pt_queue_count; 1545 } else 1546 pmap_free_l1pt(pmap->pm_l1pt); 1547 } 1548 1549 1550 /* 1551 * Retire the given physical map from service. 1552 * Should only be called if the map contains no valid mappings. 1553 */ 1554 1555 void 1556 pmap_destroy(pmap) 1557 struct pmap *pmap; 1558 { 1559 struct vm_page *page; 1560 int count; 1561 1562 if (pmap == NULL) 1563 return; 1564 1565 PDEBUG(0, printf("pmap_destroy(%p)\n", pmap)); 1566 1567 /* 1568 * Drop reference count 1569 */ 1570 simple_lock(&pmap->pm_obj.vmobjlock); 1571 count = --pmap->pm_obj.uo_refs; 1572 simple_unlock(&pmap->pm_obj.vmobjlock); 1573 if (count > 0) { 1574 return; 1575 } 1576 1577 /* 1578 * reference count is zero, free pmap resources and then free pmap. 1579 */ 1580 1581 /* Remove the zero page mapping */ 1582 pmap_remove(pmap, 0x00000000, 0x00000000 + NBPG); 1583 pmap_update(pmap); 1584 1585 /* 1586 * Free any page tables still mapped 1587 * This is only temporay until pmap_enter can count the number 1588 * of mappings made in a page table. Then pmap_remove() can 1589 * reduce the count and free the pagetable when the count 1590 * reaches zero. Note that entries in this list should match the 1591 * contents of the ptpt, however this is faster than walking a 1024 1592 * entries looking for pt's 1593 * taken from i386 pmap.c 1594 */ 1595 while (pmap->pm_obj.memq.tqh_first != NULL) { 1596 page = pmap->pm_obj.memq.tqh_first; 1597 #ifdef DIAGNOSTIC 1598 if (page->flags & PG_BUSY) 1599 panic("pmap_release: busy page table page"); 1600 #endif 1601 /* pmap_page_protect? currently no need for it. */ 1602 1603 page->wire_count = 0; 1604 uvm_pagefree(page); 1605 } 1606 1607 /* Free the page dir */ 1608 pmap_freepagedir(pmap); 1609 1610 /* return the pmap to the pool */ 1611 pool_put(&pmap_pmap_pool, pmap); 1612 } 1613 1614 1615 /* 1616 * void pmap_reference(struct pmap *pmap) 1617 * 1618 * Add a reference to the specified pmap. 1619 */ 1620 1621 void 1622 pmap_reference(pmap) 1623 struct pmap *pmap; 1624 { 1625 if (pmap == NULL) 1626 return; 1627 1628 simple_lock(&pmap->pm_lock); 1629 pmap->pm_obj.uo_refs++; 1630 simple_unlock(&pmap->pm_lock); 1631 } 1632 1633 /* 1634 * void pmap_virtual_space(vaddr_t *start, vaddr_t *end) 1635 * 1636 * Return the start and end addresses of the kernel's virtual space. 1637 * These values are setup in pmap_bootstrap and are updated as pages 1638 * are allocated. 1639 */ 1640 1641 void 1642 pmap_virtual_space(start, end) 1643 vaddr_t *start; 1644 vaddr_t *end; 1645 { 1646 *start = virtual_start; 1647 *end = virtual_end; 1648 } 1649 1650 1651 /* 1652 * Activate the address space for the specified process. If the process 1653 * is the current process, load the new MMU context. 1654 */ 1655 void 1656 pmap_activate(p) 1657 struct proc *p; 1658 { 1659 struct pmap *pmap = p->p_vmspace->vm_map.pmap; 1660 struct pcb *pcb = &p->p_addr->u_pcb; 1661 1662 (void) pmap_extract(pmap_kernel(), (vaddr_t)pmap->pm_pdir, 1663 (paddr_t *)&pcb->pcb_pagedir); 1664 1665 PDEBUG(0, printf("pmap_activate: p=%p pmap=%p pcb=%p pdir=%p l1=%p\n", 1666 p, pmap, pcb, pmap->pm_pdir, pcb->pcb_pagedir)); 1667 1668 if (p == curproc) { 1669 PDEBUG(0, printf("pmap_activate: setting TTB\n")); 1670 setttb((u_int)pcb->pcb_pagedir); 1671 } 1672 #if 0 1673 pmap->pm_pdchanged = FALSE; 1674 #endif 1675 } 1676 1677 1678 /* 1679 * Deactivate the address space of the specified process. 1680 */ 1681 void 1682 pmap_deactivate(p) 1683 struct proc *p; 1684 { 1685 } 1686 1687 /* 1688 * Perform any deferred pmap operations. 1689 */ 1690 void 1691 pmap_update(struct pmap *pmap) 1692 { 1693 1694 /* 1695 * We haven't deferred any pmap operations, but we do need to 1696 * make sure TLB/cache operations have completed. 1697 */ 1698 cpu_cpwait(); 1699 } 1700 1701 /* 1702 * pmap_clean_page() 1703 * 1704 * This is a local function used to work out the best strategy to clean 1705 * a single page referenced by its entry in the PV table. It's used by 1706 * pmap_copy_page, pmap_zero page and maybe some others later on. 1707 * 1708 * Its policy is effectively: 1709 * o If there are no mappings, we don't bother doing anything with the cache. 1710 * o If there is one mapping, we clean just that page. 1711 * o If there are multiple mappings, we clean the entire cache. 1712 * 1713 * So that some functions can be further optimised, it returns 0 if it didn't 1714 * clean the entire cache, or 1 if it did. 1715 * 1716 * XXX One bug in this routine is that if the pv_entry has a single page 1717 * mapped at 0x00000000 a whole cache clean will be performed rather than 1718 * just the 1 page. Since this should not occur in everyday use and if it does 1719 * it will just result in not the most efficient clean for the page. 1720 */ 1721 static int 1722 pmap_clean_page(pv, is_src) 1723 struct pv_entry *pv; 1724 boolean_t is_src; 1725 { 1726 struct pmap *pmap; 1727 struct pv_entry *npv; 1728 int cache_needs_cleaning = 0; 1729 vaddr_t page_to_clean = 0; 1730 1731 if (pv == NULL) 1732 /* nothing mapped in so nothing to flush */ 1733 return (0); 1734 1735 /* Since we flush the cache each time we change curproc, we 1736 * only need to flush the page if it is in the current pmap. 1737 */ 1738 if (curproc) 1739 pmap = curproc->p_vmspace->vm_map.pmap; 1740 else 1741 pmap = pmap_kernel(); 1742 1743 for (npv = pv; npv; npv = npv->pv_next) { 1744 if (npv->pv_pmap == pmap) { 1745 /* The page is mapped non-cacheable in 1746 * this map. No need to flush the cache. 1747 */ 1748 if (npv->pv_flags & PT_NC) { 1749 #ifdef DIAGNOSTIC 1750 if (cache_needs_cleaning) 1751 panic("pmap_clean_page: " 1752 "cache inconsistency"); 1753 #endif 1754 break; 1755 } 1756 #if 0 1757 /* This doesn't work, because pmap_protect 1758 doesn't flush changes on pages that it 1759 has write-protected. */ 1760 1761 /* If the page is not writable and this 1762 is the source, then there is no need 1763 to flush it from the cache. */ 1764 else if (is_src && ! (npv->pv_flags & PT_Wr)) 1765 continue; 1766 #endif 1767 if (cache_needs_cleaning){ 1768 page_to_clean = 0; 1769 break; 1770 } 1771 else 1772 page_to_clean = npv->pv_va; 1773 cache_needs_cleaning = 1; 1774 } 1775 } 1776 1777 if (page_to_clean) 1778 cpu_idcache_wbinv_range(page_to_clean, NBPG); 1779 else if (cache_needs_cleaning) { 1780 cpu_idcache_wbinv_all(); 1781 return (1); 1782 } 1783 return (0); 1784 } 1785 1786 /* 1787 * pmap_zero_page() 1788 * 1789 * Zero a given physical page by mapping it at a page hook point. 1790 * In doing the zero page op, the page we zero is mapped cachable, as with 1791 * StrongARM accesses to non-cached pages are non-burst making writing 1792 * _any_ bulk data very slow. 1793 */ 1794 void 1795 pmap_zero_page(phys) 1796 paddr_t phys; 1797 { 1798 struct vm_page *pg; 1799 1800 /* Get an entry for this page, and clean it it. */ 1801 pg = PHYS_TO_VM_PAGE(phys); 1802 simple_lock(&pg->mdpage.pvh_slock); 1803 pmap_clean_page(pg->mdpage.pvh_list, FALSE); 1804 simple_unlock(&pg->mdpage.pvh_slock); 1805 1806 /* 1807 * Hook in the page, zero it, and purge the cache for that 1808 * zeroed page. Invalidate the TLB as needed. 1809 */ 1810 *page_hook0.pte = L2_PTE(phys & PG_FRAME, AP_KRW); 1811 cpu_tlb_flushD_SE(page_hook0.va); 1812 cpu_cpwait(); 1813 bzero_page(page_hook0.va); 1814 cpu_dcache_wbinv_range(page_hook0.va, NBPG); 1815 } 1816 1817 /* pmap_pageidlezero() 1818 * 1819 * The same as above, except that we assume that the page is not 1820 * mapped. This means we never have to flush the cache first. Called 1821 * from the idle loop. 1822 */ 1823 boolean_t 1824 pmap_pageidlezero(phys) 1825 paddr_t phys; 1826 { 1827 int i, *ptr; 1828 boolean_t rv = TRUE; 1829 1830 #ifdef DIAGNOSTIC 1831 struct vm_page *pg; 1832 1833 pg = PHYS_TO_VM_PAGE(phys); 1834 if (pg->mdpage.pvh_list != NULL) 1835 panic("pmap_pageidlezero: zeroing mapped page\n"); 1836 #endif 1837 1838 /* 1839 * Hook in the page, zero it, and purge the cache for that 1840 * zeroed page. Invalidate the TLB as needed. 1841 */ 1842 *page_hook0.pte = L2_PTE(phys & PG_FRAME, AP_KRW); 1843 cpu_tlb_flushD_SE(page_hook0.va); 1844 cpu_cpwait(); 1845 1846 for (i = 0, ptr = (int *)page_hook0.va; 1847 i < (NBPG / sizeof(int)); i++) { 1848 if (sched_whichqs != 0) { 1849 /* 1850 * A process has become ready. Abort now, 1851 * so we don't keep it waiting while we 1852 * do slow memory access to finish this 1853 * page. 1854 */ 1855 rv = FALSE; 1856 break; 1857 } 1858 *ptr++ = 0; 1859 } 1860 1861 if (rv) 1862 /* 1863 * if we aborted we'll rezero this page again later so don't 1864 * purge it unless we finished it 1865 */ 1866 cpu_dcache_wbinv_range(page_hook0.va, NBPG); 1867 return (rv); 1868 } 1869 1870 /* 1871 * pmap_copy_page() 1872 * 1873 * Copy one physical page into another, by mapping the pages into 1874 * hook points. The same comment regarding cachability as in 1875 * pmap_zero_page also applies here. 1876 */ 1877 void 1878 pmap_copy_page(src, dest) 1879 paddr_t src; 1880 paddr_t dest; 1881 { 1882 struct vm_page *src_pg, *dest_pg; 1883 boolean_t cleanedcache; 1884 1885 /* Get PV entries for the pages, and clean them if needed. */ 1886 src_pg = PHYS_TO_VM_PAGE(src); 1887 1888 simple_lock(&src_pg->mdpage.pvh_slock); 1889 cleanedcache = pmap_clean_page(src_pg->mdpage.pvh_list, TRUE); 1890 simple_unlock(&src_pg->mdpage.pvh_slock); 1891 1892 if (cleanedcache == 0) { 1893 dest_pg = PHYS_TO_VM_PAGE(dest); 1894 simple_lock(&dest_pg->mdpage.pvh_slock); 1895 pmap_clean_page(dest_pg->mdpage.pvh_list, FALSE); 1896 simple_unlock(&dest_pg->mdpage.pvh_slock); 1897 } 1898 /* 1899 * Map the pages into the page hook points, copy them, and purge 1900 * the cache for the appropriate page. Invalidate the TLB 1901 * as required. 1902 */ 1903 *page_hook0.pte = L2_PTE(src & PG_FRAME, AP_KRW); 1904 *page_hook1.pte = L2_PTE(dest & PG_FRAME, AP_KRW); 1905 cpu_tlb_flushD_SE(page_hook0.va); 1906 cpu_tlb_flushD_SE(page_hook1.va); 1907 cpu_cpwait(); 1908 bcopy_page(page_hook0.va, page_hook1.va); 1909 cpu_dcache_wbinv_range(page_hook0.va, NBPG); 1910 cpu_dcache_wbinv_range(page_hook1.va, NBPG); 1911 } 1912 1913 #if 0 1914 void 1915 pmap_pte_addref(pmap, va) 1916 struct pmap *pmap; 1917 vaddr_t va; 1918 { 1919 pd_entry_t *pde; 1920 paddr_t pa; 1921 struct vm_page *m; 1922 1923 if (pmap == pmap_kernel()) 1924 return; 1925 1926 pde = pmap_pde(pmap, va & ~(3 << PDSHIFT)); 1927 pa = pmap_pte_pa(pde); 1928 m = PHYS_TO_VM_PAGE(pa); 1929 ++m->wire_count; 1930 #ifdef MYCROFT_HACK 1931 printf("addref pmap=%p va=%08lx pde=%p pa=%08lx m=%p wire=%d\n", 1932 pmap, va, pde, pa, m, m->wire_count); 1933 #endif 1934 } 1935 1936 void 1937 pmap_pte_delref(pmap, va) 1938 struct pmap *pmap; 1939 vaddr_t va; 1940 { 1941 pd_entry_t *pde; 1942 paddr_t pa; 1943 struct vm_page *m; 1944 1945 if (pmap == pmap_kernel()) 1946 return; 1947 1948 pde = pmap_pde(pmap, va & ~(3 << PDSHIFT)); 1949 pa = pmap_pte_pa(pde); 1950 m = PHYS_TO_VM_PAGE(pa); 1951 --m->wire_count; 1952 #ifdef MYCROFT_HACK 1953 printf("delref pmap=%p va=%08lx pde=%p pa=%08lx m=%p wire=%d\n", 1954 pmap, va, pde, pa, m, m->wire_count); 1955 #endif 1956 if (m->wire_count == 0) { 1957 #ifdef MYCROFT_HACK 1958 printf("delref pmap=%p va=%08lx pde=%p pa=%08lx m=%p\n", 1959 pmap, va, pde, pa, m); 1960 #endif 1961 pmap_unmap_in_l1(pmap, va); 1962 uvm_pagefree(m); 1963 --pmap->pm_stats.resident_count; 1964 } 1965 } 1966 #else 1967 #define pmap_pte_addref(pmap, va) 1968 #define pmap_pte_delref(pmap, va) 1969 #endif 1970 1971 /* 1972 * Since we have a virtually indexed cache, we may need to inhibit caching if 1973 * there is more than one mapping and at least one of them is writable. 1974 * Since we purge the cache on every context switch, we only need to check for 1975 * other mappings within the same pmap, or kernel_pmap. 1976 * This function is also called when a page is unmapped, to possibly reenable 1977 * caching on any remaining mappings. 1978 * 1979 * The code implements the following logic, where: 1980 * 1981 * KW = # of kernel read/write pages 1982 * KR = # of kernel read only pages 1983 * UW = # of user read/write pages 1984 * UR = # of user read only pages 1985 * OW = # of user read/write pages in another pmap, then 1986 * 1987 * KC = kernel mapping is cacheable 1988 * UC = user mapping is cacheable 1989 * 1990 * KW=0,KR=0 KW=0,KR>0 KW=1,KR=0 KW>1,KR>=0 1991 * +--------------------------------------------- 1992 * UW=0,UR=0,OW=0 | --- KC=1 KC=1 KC=0 1993 * UW=0,UR>0,OW=0 | UC=1 KC=1,UC=1 KC=0,UC=0 KC=0,UC=0 1994 * UW=0,UR>0,OW>0 | UC=1 KC=0,UC=1 KC=0,UC=0 KC=0,UC=0 1995 * UW=1,UR=0,OW=0 | UC=1 KC=0,UC=0 KC=0,UC=0 KC=0,UC=0 1996 * UW>1,UR>=0,OW>=0 | UC=0 KC=0,UC=0 KC=0,UC=0 KC=0,UC=0 1997 * 1998 * Note that the pmap must have it's ptes mapped in, and passed with ptes. 1999 */ 2000 __inline static void 2001 pmap_vac_me_harder(struct pmap *pmap, struct vm_page *pg, pt_entry_t *ptes, 2002 boolean_t clear_cache) 2003 { 2004 if (pmap == pmap_kernel()) 2005 pmap_vac_me_kpmap(pmap, pg, ptes, clear_cache); 2006 else 2007 pmap_vac_me_user(pmap, pg, ptes, clear_cache); 2008 } 2009 2010 static void 2011 pmap_vac_me_kpmap(struct pmap *pmap, struct vm_page *pg, pt_entry_t *ptes, 2012 boolean_t clear_cache) 2013 { 2014 int user_entries = 0; 2015 int user_writable = 0; 2016 int user_cacheable = 0; 2017 int kernel_entries = 0; 2018 int kernel_writable = 0; 2019 int kernel_cacheable = 0; 2020 struct pv_entry *pv; 2021 struct pmap *last_pmap = pmap; 2022 2023 #ifdef DIAGNOSTIC 2024 if (pmap != pmap_kernel()) 2025 panic("pmap_vac_me_kpmap: pmap != pmap_kernel()"); 2026 #endif 2027 2028 /* 2029 * Pass one, see if there are both kernel and user pmaps for 2030 * this page. Calculate whether there are user-writable or 2031 * kernel-writable pages. 2032 */ 2033 for (pv = pg->mdpage.pvh_list; pv != NULL; pv = pv->pv_next) { 2034 if (pv->pv_pmap != pmap) { 2035 user_entries++; 2036 if (pv->pv_flags & PT_Wr) 2037 user_writable++; 2038 if ((pv->pv_flags & PT_NC) == 0) 2039 user_cacheable++; 2040 } else { 2041 kernel_entries++; 2042 if (pv->pv_flags & PT_Wr) 2043 kernel_writable++; 2044 if ((pv->pv_flags & PT_NC) == 0) 2045 kernel_cacheable++; 2046 } 2047 } 2048 2049 /* 2050 * We know we have just been updating a kernel entry, so if 2051 * all user pages are already cacheable, then there is nothing 2052 * further to do. 2053 */ 2054 if (kernel_entries == 0 && 2055 user_cacheable == user_entries) 2056 return; 2057 2058 if (user_entries) { 2059 /* 2060 * Scan over the list again, for each entry, if it 2061 * might not be set correctly, call pmap_vac_me_user 2062 * to recalculate the settings. 2063 */ 2064 for (pv = pg->mdpage.pvh_list; pv; pv = pv->pv_next) { 2065 /* 2066 * We know kernel mappings will get set 2067 * correctly in other calls. We also know 2068 * that if the pmap is the same as last_pmap 2069 * then we've just handled this entry. 2070 */ 2071 if (pv->pv_pmap == pmap || pv->pv_pmap == last_pmap) 2072 continue; 2073 /* 2074 * If there are kernel entries and this page 2075 * is writable but non-cacheable, then we can 2076 * skip this entry also. 2077 */ 2078 if (kernel_entries > 0 && 2079 (pv->pv_flags & (PT_NC | PT_Wr)) == 2080 (PT_NC | PT_Wr)) 2081 continue; 2082 /* 2083 * Similarly if there are no kernel-writable 2084 * entries and the page is already 2085 * read-only/cacheable. 2086 */ 2087 if (kernel_writable == 0 && 2088 (pv->pv_flags & (PT_NC | PT_Wr)) == 0) 2089 continue; 2090 /* 2091 * For some of the remaining cases, we know 2092 * that we must recalculate, but for others we 2093 * can't tell if they are correct or not, so 2094 * we recalculate anyway. 2095 */ 2096 pmap_unmap_ptes(last_pmap); 2097 last_pmap = pv->pv_pmap; 2098 ptes = pmap_map_ptes(last_pmap); 2099 pmap_vac_me_user(last_pmap, pg, ptes, 2100 pmap_is_curpmap(last_pmap)); 2101 } 2102 /* Restore the pte mapping that was passed to us. */ 2103 if (last_pmap != pmap) { 2104 pmap_unmap_ptes(last_pmap); 2105 ptes = pmap_map_ptes(pmap); 2106 } 2107 if (kernel_entries == 0) 2108 return; 2109 } 2110 2111 pmap_vac_me_user(pmap, pg, ptes, clear_cache); 2112 return; 2113 } 2114 2115 static void 2116 pmap_vac_me_user(struct pmap *pmap, struct vm_page *pg, pt_entry_t *ptes, 2117 boolean_t clear_cache) 2118 { 2119 struct pmap *kpmap = pmap_kernel(); 2120 struct pv_entry *pv, *npv; 2121 int entries = 0; 2122 int writable = 0; 2123 int cacheable_entries = 0; 2124 int kern_cacheable = 0; 2125 int other_writable = 0; 2126 2127 pv = pg->mdpage.pvh_list; 2128 KASSERT(ptes != NULL); 2129 2130 /* 2131 * Count mappings and writable mappings in this pmap. 2132 * Include kernel mappings as part of our own. 2133 * Keep a pointer to the first one. 2134 */ 2135 for (npv = pv; npv; npv = npv->pv_next) { 2136 /* Count mappings in the same pmap */ 2137 if (pmap == npv->pv_pmap || 2138 kpmap == npv->pv_pmap) { 2139 if (entries++ == 0) 2140 pv = npv; 2141 /* Cacheable mappings */ 2142 if ((npv->pv_flags & PT_NC) == 0) { 2143 cacheable_entries++; 2144 if (kpmap == npv->pv_pmap) 2145 kern_cacheable++; 2146 } 2147 /* Writable mappings */ 2148 if (npv->pv_flags & PT_Wr) 2149 ++writable; 2150 } else if (npv->pv_flags & PT_Wr) 2151 other_writable = 1; 2152 } 2153 2154 PDEBUG(3,printf("pmap_vac_me_harder: pmap %p Entries %d, " 2155 "writable %d cacheable %d %s\n", pmap, entries, writable, 2156 cacheable_entries, clear_cache ? "clean" : "no clean")); 2157 2158 /* 2159 * Enable or disable caching as necessary. 2160 * Note: the first entry might be part of the kernel pmap, 2161 * so we can't assume this is indicative of the state of the 2162 * other (maybe non-kpmap) entries. 2163 */ 2164 if ((entries > 1 && writable) || 2165 (entries > 0 && pmap == kpmap && other_writable)) { 2166 if (cacheable_entries == 0) 2167 return; 2168 for (npv = pv; npv; npv = npv->pv_next) { 2169 if ((pmap == npv->pv_pmap 2170 || kpmap == npv->pv_pmap) && 2171 (npv->pv_flags & PT_NC) == 0) { 2172 ptes[arm_byte_to_page(npv->pv_va)] &= 2173 ~(PT_C | PT_B); 2174 npv->pv_flags |= PT_NC; 2175 /* 2176 * If this page needs flushing from the 2177 * cache, and we aren't going to do it 2178 * below, do it now. 2179 */ 2180 if ((cacheable_entries < 4 && 2181 (clear_cache || npv->pv_pmap == kpmap)) || 2182 (npv->pv_pmap == kpmap && 2183 !clear_cache && kern_cacheable < 4)) { 2184 cpu_idcache_wbinv_range(npv->pv_va, 2185 NBPG); 2186 cpu_tlb_flushID_SE(npv->pv_va); 2187 } 2188 } 2189 } 2190 if ((clear_cache && cacheable_entries >= 4) || 2191 kern_cacheable >= 4) { 2192 cpu_idcache_wbinv_all(); 2193 cpu_tlb_flushID(); 2194 } 2195 cpu_cpwait(); 2196 } else if (entries > 0) { 2197 /* 2198 * Turn cacheing back on for some pages. If it is a kernel 2199 * page, only do so if there are no other writable pages. 2200 */ 2201 for (npv = pv; npv; npv = npv->pv_next) { 2202 if ((pmap == npv->pv_pmap || 2203 (kpmap == npv->pv_pmap && other_writable == 0)) && 2204 (npv->pv_flags & PT_NC)) { 2205 ptes[arm_byte_to_page(npv->pv_va)] |= 2206 pte_cache_mode; 2207 npv->pv_flags &= ~PT_NC; 2208 } 2209 } 2210 } 2211 } 2212 2213 /* 2214 * pmap_remove() 2215 * 2216 * pmap_remove is responsible for nuking a number of mappings for a range 2217 * of virtual address space in the current pmap. To do this efficiently 2218 * is interesting, because in a number of cases a wide virtual address 2219 * range may be supplied that contains few actual mappings. So, the 2220 * optimisations are: 2221 * 1. Try and skip over hunks of address space for which an L1 entry 2222 * does not exist. 2223 * 2. Build up a list of pages we've hit, up to a maximum, so we can 2224 * maybe do just a partial cache clean. This path of execution is 2225 * complicated by the fact that the cache must be flushed _before_ 2226 * the PTE is nuked, being a VAC :-) 2227 * 3. Maybe later fast-case a single page, but I don't think this is 2228 * going to make _that_ much difference overall. 2229 */ 2230 2231 #define PMAP_REMOVE_CLEAN_LIST_SIZE 3 2232 2233 void 2234 pmap_remove(pmap, sva, eva) 2235 struct pmap *pmap; 2236 vaddr_t sva; 2237 vaddr_t eva; 2238 { 2239 int cleanlist_idx = 0; 2240 struct pagelist { 2241 vaddr_t va; 2242 pt_entry_t *pte; 2243 } cleanlist[PMAP_REMOVE_CLEAN_LIST_SIZE]; 2244 pt_entry_t *pte = 0, *ptes; 2245 paddr_t pa; 2246 int pmap_active; 2247 struct vm_page *pg; 2248 2249 /* Exit quick if there is no pmap */ 2250 if (!pmap) 2251 return; 2252 2253 PDEBUG(0, printf("pmap_remove: pmap=%p sva=%08lx eva=%08lx\n", pmap, sva, eva)); 2254 2255 sva &= PG_FRAME; 2256 eva &= PG_FRAME; 2257 2258 /* 2259 * we lock in the pmap => vm_page direction 2260 */ 2261 PMAP_MAP_TO_HEAD_LOCK(); 2262 2263 ptes = pmap_map_ptes(pmap); 2264 /* Get a page table pointer */ 2265 while (sva < eva) { 2266 if (pmap_pde_page(pmap_pde(pmap, sva))) 2267 break; 2268 sva = (sva & PD_MASK) + NBPD; 2269 } 2270 2271 pte = &ptes[arm_byte_to_page(sva)]; 2272 /* Note if the pmap is active thus require cache and tlb cleans */ 2273 if ((curproc && curproc->p_vmspace->vm_map.pmap == pmap) 2274 || (pmap == pmap_kernel())) 2275 pmap_active = 1; 2276 else 2277 pmap_active = 0; 2278 2279 /* Now loop along */ 2280 while (sva < eva) { 2281 /* Check if we can move to the next PDE (l1 chunk) */ 2282 if (!(sva & PT_MASK)) 2283 if (!pmap_pde_page(pmap_pde(pmap, sva))) { 2284 sva += NBPD; 2285 pte += arm_byte_to_page(NBPD); 2286 continue; 2287 } 2288 2289 /* We've found a valid PTE, so this page of PTEs has to go. */ 2290 if (pmap_pte_v(pte)) { 2291 /* Update statistics */ 2292 --pmap->pm_stats.resident_count; 2293 2294 /* 2295 * Add this page to our cache remove list, if we can. 2296 * If, however the cache remove list is totally full, 2297 * then do a complete cache invalidation taking note 2298 * to backtrack the PTE table beforehand, and ignore 2299 * the lists in future because there's no longer any 2300 * point in bothering with them (we've paid the 2301 * penalty, so will carry on unhindered). Otherwise, 2302 * when we fall out, we just clean the list. 2303 */ 2304 PDEBUG(10, printf("remove: inv pte at %p(%x) ", pte, *pte)); 2305 pa = pmap_pte_pa(pte); 2306 2307 if (cleanlist_idx < PMAP_REMOVE_CLEAN_LIST_SIZE) { 2308 /* Add to the clean list. */ 2309 cleanlist[cleanlist_idx].pte = pte; 2310 cleanlist[cleanlist_idx].va = sva; 2311 cleanlist_idx++; 2312 } else if (cleanlist_idx == PMAP_REMOVE_CLEAN_LIST_SIZE) { 2313 int cnt; 2314 2315 /* Nuke everything if needed. */ 2316 if (pmap_active) { 2317 cpu_idcache_wbinv_all(); 2318 cpu_tlb_flushID(); 2319 } 2320 2321 /* 2322 * Roll back the previous PTE list, 2323 * and zero out the current PTE. 2324 */ 2325 for (cnt = 0; cnt < PMAP_REMOVE_CLEAN_LIST_SIZE; cnt++) { 2326 *cleanlist[cnt].pte = 0; 2327 pmap_pte_delref(pmap, cleanlist[cnt].va); 2328 } 2329 *pte = 0; 2330 pmap_pte_delref(pmap, sva); 2331 cleanlist_idx++; 2332 } else { 2333 /* 2334 * We've already nuked the cache and 2335 * TLB, so just carry on regardless, 2336 * and we won't need to do it again 2337 */ 2338 *pte = 0; 2339 pmap_pte_delref(pmap, sva); 2340 } 2341 2342 /* 2343 * Update flags. In a number of circumstances, 2344 * we could cluster a lot of these and do a 2345 * number of sequential pages in one go. 2346 */ 2347 if ((pg = PHYS_TO_VM_PAGE(pa)) != NULL) { 2348 struct pv_entry *pve; 2349 simple_lock(&pg->mdpage.pvh_slock); 2350 pve = pmap_remove_pv(pg, pmap, sva); 2351 pmap_free_pv(pmap, pve); 2352 pmap_vac_me_harder(pmap, pg, ptes, FALSE); 2353 simple_unlock(&pg->mdpage.pvh_slock); 2354 } 2355 } 2356 sva += NBPG; 2357 pte++; 2358 } 2359 2360 pmap_unmap_ptes(pmap); 2361 /* 2362 * Now, if we've fallen through down to here, chances are that there 2363 * are less than PMAP_REMOVE_CLEAN_LIST_SIZE mappings left. 2364 */ 2365 if (cleanlist_idx <= PMAP_REMOVE_CLEAN_LIST_SIZE) { 2366 u_int cnt; 2367 2368 for (cnt = 0; cnt < cleanlist_idx; cnt++) { 2369 if (pmap_active) { 2370 cpu_idcache_wbinv_range(cleanlist[cnt].va, 2371 NBPG); 2372 *cleanlist[cnt].pte = 0; 2373 cpu_tlb_flushID_SE(cleanlist[cnt].va); 2374 } else 2375 *cleanlist[cnt].pte = 0; 2376 pmap_pte_delref(pmap, cleanlist[cnt].va); 2377 } 2378 } 2379 PMAP_MAP_TO_HEAD_UNLOCK(); 2380 } 2381 2382 /* 2383 * Routine: pmap_remove_all 2384 * Function: 2385 * Removes this physical page from 2386 * all physical maps in which it resides. 2387 * Reflects back modify bits to the pager. 2388 */ 2389 2390 static void 2391 pmap_remove_all(pg) 2392 struct vm_page *pg; 2393 { 2394 struct pv_entry *pv, *npv; 2395 struct pmap *pmap; 2396 pt_entry_t *pte, *ptes; 2397 2398 PDEBUG(0, printf("pmap_remove_all: pa=%lx ", VM_PAGE_TO_PHYS(pg))); 2399 2400 /* set vm_page => pmap locking */ 2401 PMAP_HEAD_TO_MAP_LOCK(); 2402 2403 simple_lock(&pg->mdpage.pvh_slock); 2404 2405 pv = pg->mdpage.pvh_list; 2406 if (pv == NULL) { 2407 PDEBUG(0, printf("free page\n")); 2408 simple_unlock(&pg->mdpage.pvh_slock); 2409 PMAP_HEAD_TO_MAP_UNLOCK(); 2410 return; 2411 } 2412 pmap_clean_page(pv, FALSE); 2413 2414 while (pv) { 2415 pmap = pv->pv_pmap; 2416 ptes = pmap_map_ptes(pmap); 2417 pte = &ptes[arm_byte_to_page(pv->pv_va)]; 2418 2419 PDEBUG(0, printf("[%p,%08x,%08lx,%08x] ", pmap, *pte, 2420 pv->pv_va, pv->pv_flags)); 2421 #ifdef DEBUG 2422 if (!pmap_pde_page(pmap_pde(pmap, pv->pv_va)) || 2423 !pmap_pte_v(pte) || pmap_pte_pa(pte) != pa) 2424 panic("pmap_remove_all: bad mapping"); 2425 #endif /* DEBUG */ 2426 2427 /* 2428 * Update statistics 2429 */ 2430 --pmap->pm_stats.resident_count; 2431 2432 /* Wired bit */ 2433 if (pv->pv_flags & PT_W) 2434 --pmap->pm_stats.wired_count; 2435 2436 /* 2437 * Invalidate the PTEs. 2438 * XXX: should cluster them up and invalidate as many 2439 * as possible at once. 2440 */ 2441 2442 #ifdef needednotdone 2443 reduce wiring count on page table pages as references drop 2444 #endif 2445 2446 *pte = 0; 2447 pmap_pte_delref(pmap, pv->pv_va); 2448 2449 npv = pv->pv_next; 2450 pmap_free_pv(pmap, pv); 2451 pv = npv; 2452 pmap_unmap_ptes(pmap); 2453 } 2454 pg->mdpage.pvh_list = NULL; 2455 simple_unlock(&pg->mdpage.pvh_slock); 2456 PMAP_HEAD_TO_MAP_UNLOCK(); 2457 2458 PDEBUG(0, printf("done\n")); 2459 cpu_tlb_flushID(); 2460 cpu_cpwait(); 2461 } 2462 2463 2464 /* 2465 * Set the physical protection on the specified range of this map as requested. 2466 */ 2467 2468 void 2469 pmap_protect(pmap, sva, eva, prot) 2470 struct pmap *pmap; 2471 vaddr_t sva; 2472 vaddr_t eva; 2473 vm_prot_t prot; 2474 { 2475 pt_entry_t *pte = NULL, *ptes; 2476 struct vm_page *pg; 2477 int armprot; 2478 int flush = 0; 2479 paddr_t pa; 2480 2481 PDEBUG(0, printf("pmap_protect: pmap=%p %08lx->%08lx %x\n", 2482 pmap, sva, eva, prot)); 2483 2484 if (~prot & VM_PROT_READ) { 2485 /* Just remove the mappings. */ 2486 pmap_remove(pmap, sva, eva); 2487 /* pmap_update not needed as it should be called by the caller 2488 * of pmap_protect */ 2489 return; 2490 } 2491 if (prot & VM_PROT_WRITE) { 2492 /* 2493 * If this is a read->write transition, just ignore it and let 2494 * uvm_fault() take care of it later. 2495 */ 2496 return; 2497 } 2498 2499 sva &= PG_FRAME; 2500 eva &= PG_FRAME; 2501 2502 /* Need to lock map->head */ 2503 PMAP_MAP_TO_HEAD_LOCK(); 2504 2505 ptes = pmap_map_ptes(pmap); 2506 /* 2507 * We need to acquire a pointer to a page table page before entering 2508 * the following loop. 2509 */ 2510 while (sva < eva) { 2511 if (pmap_pde_page(pmap_pde(pmap, sva))) 2512 break; 2513 sva = (sva & PD_MASK) + NBPD; 2514 } 2515 2516 pte = &ptes[arm_byte_to_page(sva)]; 2517 2518 while (sva < eva) { 2519 /* only check once in a while */ 2520 if ((sva & PT_MASK) == 0) { 2521 if (!pmap_pde_page(pmap_pde(pmap, sva))) { 2522 /* We can race ahead here, to the next pde. */ 2523 sva += NBPD; 2524 pte += arm_byte_to_page(NBPD); 2525 continue; 2526 } 2527 } 2528 2529 if (!pmap_pte_v(pte)) 2530 goto next; 2531 2532 flush = 1; 2533 2534 armprot = 0; 2535 if (sva < VM_MAXUSER_ADDRESS) 2536 armprot |= PT_AP(AP_U); 2537 else if (sva < VM_MAX_ADDRESS) 2538 armprot |= PT_AP(AP_W); /* XXX Ekk what is this ? */ 2539 *pte = (*pte & 0xfffff00f) | armprot; 2540 2541 pa = pmap_pte_pa(pte); 2542 2543 /* Get the physical page index */ 2544 2545 /* Clear write flag */ 2546 if ((pg = PHYS_TO_VM_PAGE(pa)) != NULL) { 2547 simple_lock(&pg->mdpage.pvh_slock); 2548 (void) pmap_modify_pv(pmap, sva, pg, PT_Wr, 0); 2549 pmap_vac_me_harder(pmap, pg, ptes, FALSE); 2550 simple_unlock(&pg->mdpage.pvh_slock); 2551 } 2552 2553 next: 2554 sva += NBPG; 2555 pte++; 2556 } 2557 pmap_unmap_ptes(pmap); 2558 PMAP_MAP_TO_HEAD_UNLOCK(); 2559 if (flush) 2560 cpu_tlb_flushID(); 2561 } 2562 2563 /* 2564 * void pmap_enter(struct pmap *pmap, vaddr_t va, paddr_t pa, vm_prot_t prot, 2565 * int flags) 2566 * 2567 * Insert the given physical page (p) at 2568 * the specified virtual address (v) in the 2569 * target physical map with the protection requested. 2570 * 2571 * If specified, the page will be wired down, meaning 2572 * that the related pte can not be reclaimed. 2573 * 2574 * NB: This is the only routine which MAY NOT lazy-evaluate 2575 * or lose information. That is, this routine must actually 2576 * insert this page into the given map NOW. 2577 */ 2578 2579 int 2580 pmap_enter(pmap, va, pa, prot, flags) 2581 struct pmap *pmap; 2582 vaddr_t va; 2583 paddr_t pa; 2584 vm_prot_t prot; 2585 int flags; 2586 { 2587 pt_entry_t *pte, *ptes; 2588 u_int npte; 2589 paddr_t opa; 2590 int nflags; 2591 boolean_t wired = (flags & PMAP_WIRED) != 0; 2592 struct vm_page *pg; 2593 struct pv_entry *pve; 2594 int error; 2595 2596 PDEBUG(5, printf("pmap_enter: V%08lx P%08lx in pmap %p prot=%08x, wired = %d\n", 2597 va, pa, pmap, prot, wired)); 2598 2599 #ifdef DIAGNOSTIC 2600 /* Valid address ? */ 2601 if (va >= (KERNEL_VM_BASE + KERNEL_VM_SIZE)) 2602 panic("pmap_enter: too big"); 2603 if (pmap != pmap_kernel() && va != 0) { 2604 if (va < VM_MIN_ADDRESS || va >= VM_MAXUSER_ADDRESS) 2605 panic("pmap_enter: kernel page in user map"); 2606 } else { 2607 if (va >= VM_MIN_ADDRESS && va < VM_MAXUSER_ADDRESS) 2608 panic("pmap_enter: user page in kernel map"); 2609 if (va >= VM_MAXUSER_ADDRESS && va < VM_MAX_ADDRESS) 2610 panic("pmap_enter: entering PT page"); 2611 } 2612 #endif 2613 /* 2614 * Get a pointer to the page. Later on in this function, we 2615 * test for a managed page by checking pg != NULL. 2616 */ 2617 pg = PHYS_TO_VM_PAGE(pa); 2618 2619 /* get lock */ 2620 PMAP_MAP_TO_HEAD_LOCK(); 2621 /* 2622 * Get a pointer to the pte for this virtual address. If the 2623 * pte pointer is NULL then we are missing the L2 page table 2624 * so we need to create one. 2625 */ 2626 /* XXX horrible hack to get us working with lockdebug */ 2627 simple_lock(&pmap->pm_obj.vmobjlock); 2628 pte = pmap_pte(pmap, va); 2629 if (!pte) { 2630 struct vm_page *ptp; 2631 2632 /* if failure is allowed then don't try too hard */ 2633 ptp = pmap_get_ptp(pmap, va, flags & PMAP_CANFAIL); 2634 if (ptp == NULL) { 2635 if (flags & PMAP_CANFAIL) { 2636 error = ENOMEM; 2637 goto out; 2638 } 2639 panic("pmap_enter: get ptp failed"); 2640 } 2641 2642 pte = pmap_pte(pmap, va); 2643 #ifdef DIAGNOSTIC 2644 if (!pte) 2645 panic("pmap_enter: no pte"); 2646 #endif 2647 } 2648 2649 nflags = 0; 2650 if (prot & VM_PROT_WRITE) 2651 nflags |= PT_Wr; 2652 if (wired) 2653 nflags |= PT_W; 2654 2655 /* More debugging info */ 2656 PDEBUG(5, printf("pmap_enter: pte for V%08lx = V%p (%08x)\n", va, pte, 2657 *pte)); 2658 2659 /* Is the pte valid ? If so then this page is already mapped */ 2660 if (pmap_pte_v(pte)) { 2661 /* Get the physical address of the current page mapped */ 2662 opa = pmap_pte_pa(pte); 2663 2664 #ifdef MYCROFT_HACK 2665 printf("pmap_enter: pmap=%p va=%lx pa=%lx opa=%lx\n", pmap, va, pa, opa); 2666 #endif 2667 2668 /* Are we mapping the same page ? */ 2669 if (opa == pa) { 2670 /* All we must be doing is changing the protection */ 2671 PDEBUG(0, printf("Case 02 in pmap_enter (V%08lx P%08lx)\n", 2672 va, pa)); 2673 2674 /* Has the wiring changed ? */ 2675 if (pg != NULL) { 2676 simple_lock(&pg->mdpage.pvh_slock); 2677 (void) pmap_modify_pv(pmap, va, pg, 2678 PT_Wr | PT_W, nflags); 2679 simple_unlock(&pg->mdpage.pvh_slock); 2680 } 2681 } else { 2682 /* We are replacing the page with a new one. */ 2683 cpu_idcache_wbinv_range(va, NBPG); 2684 2685 PDEBUG(0, printf("Case 03 in pmap_enter (V%08lx P%08lx P%08lx)\n", 2686 va, pa, opa)); 2687 2688 /* 2689 * If it is part of our managed memory then we 2690 * must remove it from the PV list 2691 */ 2692 if (pg != NULL) { 2693 simple_lock(&pg->mdpage.pvh_slock); 2694 pve = pmap_remove_pv(pg, pmap, va); 2695 simple_unlock(&pg->mdpage.pvh_slock); 2696 } else { 2697 pve = NULL; 2698 } 2699 2700 goto enter; 2701 } 2702 } else { 2703 opa = 0; 2704 pve = NULL; 2705 pmap_pte_addref(pmap, va); 2706 2707 /* pte is not valid so we must be hooking in a new page */ 2708 ++pmap->pm_stats.resident_count; 2709 2710 enter: 2711 /* 2712 * Enter on the PV list if part of our managed memory 2713 */ 2714 if (pmap_initialized && pg != NULL) { 2715 if (pve == NULL) { 2716 pve = pmap_alloc_pv(pmap, ALLOCPV_NEED); 2717 if (pve == NULL) { 2718 if (flags & PMAP_CANFAIL) { 2719 error = ENOMEM; 2720 goto out; 2721 } 2722 panic("pmap_enter: no pv entries available"); 2723 } 2724 } 2725 /* enter_pv locks pvh when adding */ 2726 pmap_enter_pv(pg, pve, pmap, va, NULL, nflags); 2727 } else { 2728 pg = NULL; 2729 if (pve != NULL) 2730 pmap_free_pv(pmap, pve); 2731 } 2732 } 2733 2734 #ifdef MYCROFT_HACK 2735 if (mycroft_hack) 2736 printf("pmap_enter: pmap=%p va=%lx pa=%lx opa=%lx bank=%d off=%d pv=%p\n", pmap, va, pa, opa, bank, off, pv); 2737 #endif 2738 2739 /* Construct the pte, giving the correct access. */ 2740 npte = (pa & PG_FRAME); 2741 2742 /* VA 0 is magic. */ 2743 if (pmap != pmap_kernel() && va != 0) 2744 npte |= PT_AP(AP_U); 2745 2746 if (pmap_initialized && pg != NULL) { 2747 #ifdef DIAGNOSTIC 2748 if ((flags & VM_PROT_ALL) & ~prot) 2749 panic("pmap_enter: access_type exceeds prot"); 2750 #endif 2751 npte |= pte_cache_mode; 2752 if (flags & VM_PROT_WRITE) { 2753 npte |= L2_SPAGE | PT_AP(AP_W); 2754 pg->mdpage.pvh_attrs |= PT_H | PT_M; 2755 } else if (flags & VM_PROT_ALL) { 2756 npte |= L2_SPAGE; 2757 pg->mdpage.pvh_attrs |= PT_H; 2758 } else 2759 npte |= L2_INVAL; 2760 } else { 2761 if (prot & VM_PROT_WRITE) 2762 npte |= L2_SPAGE | PT_AP(AP_W); 2763 else if (prot & VM_PROT_ALL) 2764 npte |= L2_SPAGE; 2765 else 2766 npte |= L2_INVAL; 2767 } 2768 2769 #ifdef MYCROFT_HACK 2770 if (mycroft_hack) 2771 printf("pmap_enter: pmap=%p va=%lx pa=%lx prot=%x wired=%d access_type=%x npte=%08x\n", pmap, va, pa, prot, wired, flags & VM_PROT_ALL, npte); 2772 #endif 2773 2774 *pte = npte; 2775 2776 if (pmap_initialized && pg != NULL) { 2777 boolean_t pmap_active = FALSE; 2778 /* XXX this will change once the whole of pmap_enter uses 2779 * map_ptes 2780 */ 2781 ptes = pmap_map_ptes(pmap); 2782 if ((curproc && curproc->p_vmspace->vm_map.pmap == pmap) 2783 || (pmap == pmap_kernel())) 2784 pmap_active = TRUE; 2785 simple_lock(&pg->mdpage.pvh_slock); 2786 pmap_vac_me_harder(pmap, pg, ptes, pmap_active); 2787 simple_unlock(&pg->mdpage.pvh_slock); 2788 pmap_unmap_ptes(pmap); 2789 } 2790 2791 /* Better flush the TLB ... */ 2792 cpu_tlb_flushID_SE(va); 2793 error = 0; 2794 out: 2795 simple_unlock(&pmap->pm_obj.vmobjlock); 2796 PMAP_MAP_TO_HEAD_UNLOCK(); 2797 PDEBUG(5, printf("pmap_enter: pte = V%p %08x\n", pte, *pte)); 2798 2799 return error; 2800 } 2801 2802 void 2803 pmap_kenter_pa(va, pa, prot) 2804 vaddr_t va; 2805 paddr_t pa; 2806 vm_prot_t prot; 2807 { 2808 struct pmap *pmap = pmap_kernel(); 2809 pt_entry_t *pte; 2810 struct vm_page *pg; 2811 2812 if (!pmap_pde_page(pmap_pde(pmap, va))) { 2813 2814 #ifdef DIAGNOSTIC 2815 if (pmap_pde_v(pmap_pde(pmap, va))) 2816 panic("Trying to map kernel page into section mapping" 2817 " VA=%lx PA=%lx", va, pa); 2818 #endif 2819 /* 2820 * For the kernel pmaps it would be better to ensure 2821 * that they are always present, and to grow the 2822 * kernel as required. 2823 */ 2824 2825 /* must lock the pmap */ 2826 simple_lock(&(pmap_kernel()->pm_obj.vmobjlock)); 2827 /* Allocate a page table */ 2828 pg = uvm_pagealloc(&(pmap_kernel()->pm_obj), 0, NULL, 2829 UVM_PGA_USERESERVE | UVM_PGA_ZERO); 2830 if (pg == NULL) { 2831 panic("pmap_kenter_pa: no free pages"); 2832 } 2833 pg->flags &= ~PG_BUSY; /* never busy */ 2834 2835 /* Wire this page table into the L1. */ 2836 pmap_map_in_l1(pmap, va, VM_PAGE_TO_PHYS(pg), TRUE); 2837 simple_unlock(&(pmap_kernel()->pm_obj.vmobjlock)); 2838 } 2839 pte = vtopte(va); 2840 KASSERT(!pmap_pte_v(pte)); 2841 *pte = L2_PTE(pa, AP_KRW); 2842 } 2843 2844 void 2845 pmap_kremove(va, len) 2846 vaddr_t va; 2847 vsize_t len; 2848 { 2849 pt_entry_t *pte; 2850 2851 for (len >>= PAGE_SHIFT; len > 0; len--, va += PAGE_SIZE) { 2852 2853 /* 2854 * We assume that we will only be called with small 2855 * regions of memory. 2856 */ 2857 2858 KASSERT(pmap_pde_page(pmap_pde(pmap_kernel(), va))); 2859 pte = vtopte(va); 2860 cpu_idcache_wbinv_range(va, PAGE_SIZE); 2861 *pte = 0; 2862 cpu_tlb_flushID_SE(va); 2863 } 2864 } 2865 2866 /* 2867 * pmap_page_protect: 2868 * 2869 * Lower the permission for all mappings to a given page. 2870 */ 2871 2872 void 2873 pmap_page_protect(pg, prot) 2874 struct vm_page *pg; 2875 vm_prot_t prot; 2876 { 2877 2878 PDEBUG(0, printf("pmap_page_protect(pa=%lx, prot=%d)\n", 2879 VM_PAGE_TO_PHYS(pg), prot)); 2880 2881 switch(prot) { 2882 case VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE: 2883 case VM_PROT_READ|VM_PROT_WRITE: 2884 return; 2885 2886 case VM_PROT_READ: 2887 case VM_PROT_READ|VM_PROT_EXECUTE: 2888 pmap_copy_on_write(pg); 2889 break; 2890 2891 default: 2892 pmap_remove_all(pg); 2893 break; 2894 } 2895 } 2896 2897 2898 /* 2899 * Routine: pmap_unwire 2900 * Function: Clear the wired attribute for a map/virtual-address 2901 * pair. 2902 * In/out conditions: 2903 * The mapping must already exist in the pmap. 2904 */ 2905 2906 void 2907 pmap_unwire(pmap, va) 2908 struct pmap *pmap; 2909 vaddr_t va; 2910 { 2911 pt_entry_t *pte; 2912 paddr_t pa; 2913 struct vm_page *pg; 2914 2915 /* 2916 * Make sure pmap is valid. -dct 2917 */ 2918 if (pmap == NULL) 2919 return; 2920 2921 /* Get the pte */ 2922 pte = pmap_pte(pmap, va); 2923 if (!pte) 2924 return; 2925 2926 /* Extract the physical address of the page */ 2927 pa = pmap_pte_pa(pte); 2928 2929 if ((pg = PHYS_TO_VM_PAGE(pa)) == NULL) 2930 return; 2931 2932 simple_lock(&pg->mdpage.pvh_slock); 2933 /* Update the wired bit in the pv entry for this page. */ 2934 (void) pmap_modify_pv(pmap, va, pg, PT_W, 0); 2935 simple_unlock(&pg->mdpage.pvh_slock); 2936 } 2937 2938 /* 2939 * pt_entry_t *pmap_pte(struct pmap *pmap, vaddr_t va) 2940 * 2941 * Return the pointer to a page table entry corresponding to the supplied 2942 * virtual address. 2943 * 2944 * The page directory is first checked to make sure that a page table 2945 * for the address in question exists and if it does a pointer to the 2946 * entry is returned. 2947 * 2948 * The way this works is that that the kernel page tables are mapped 2949 * into the memory map at ALT_PAGE_TBLS_BASE to ALT_PAGE_TBLS_BASE+4MB. 2950 * This allows page tables to be located quickly. 2951 */ 2952 pt_entry_t * 2953 pmap_pte(pmap, va) 2954 struct pmap *pmap; 2955 vaddr_t va; 2956 { 2957 pt_entry_t *ptp; 2958 pt_entry_t *result; 2959 2960 /* The pmap must be valid */ 2961 if (!pmap) 2962 return(NULL); 2963 2964 /* Return the address of the pte */ 2965 PDEBUG(10, printf("pmap_pte: pmap=%p va=V%08lx pde = V%p (%08X)\n", 2966 pmap, va, pmap_pde(pmap, va), *(pmap_pde(pmap, va)))); 2967 2968 /* Do we have a valid pde ? If not we don't have a page table */ 2969 if (!pmap_pde_page(pmap_pde(pmap, va))) { 2970 PDEBUG(0, printf("pmap_pte: failed - pde = %p\n", 2971 pmap_pde(pmap, va))); 2972 return(NULL); 2973 } 2974 2975 PDEBUG(10, printf("pmap pagetable = P%08lx current = P%08x\n", 2976 pmap->pm_pptpt, (*((pt_entry_t *)(PROCESS_PAGE_TBLS_BASE 2977 + (PROCESS_PAGE_TBLS_BASE >> (PGSHIFT - 2)) + 2978 (PROCESS_PAGE_TBLS_BASE >> PDSHIFT))) & PG_FRAME))); 2979 2980 /* 2981 * If the pmap is the kernel pmap or the pmap is the active one 2982 * then we can just return a pointer to entry relative to 2983 * PROCESS_PAGE_TBLS_BASE. 2984 * Otherwise we need to map the page tables to an alternative 2985 * address and reference them there. 2986 */ 2987 if (pmap == pmap_kernel() || pmap->pm_pptpt 2988 == (*((pt_entry_t *)(PROCESS_PAGE_TBLS_BASE 2989 + ((PROCESS_PAGE_TBLS_BASE >> (PGSHIFT - 2)) & 2990 ~3) + (PROCESS_PAGE_TBLS_BASE >> PDSHIFT))) & PG_FRAME)) { 2991 ptp = (pt_entry_t *)PROCESS_PAGE_TBLS_BASE; 2992 } else { 2993 struct proc *p = curproc; 2994 2995 /* If we don't have a valid curproc use proc0 */ 2996 /* Perhaps we should just use kernel_pmap instead */ 2997 if (p == NULL) 2998 p = &proc0; 2999 #ifdef DIAGNOSTIC 3000 /* 3001 * The pmap should always be valid for the process so 3002 * panic if it is not. 3003 */ 3004 if (!p->p_vmspace || !p->p_vmspace->vm_map.pmap) { 3005 printf("pmap_pte: va=%08lx p=%p vm=%p\n", 3006 va, p, p->p_vmspace); 3007 console_debugger(); 3008 } 3009 /* 3010 * The pmap for the current process should be mapped. If it 3011 * is not then we have a problem. 3012 */ 3013 if (p->p_vmspace->vm_map.pmap->pm_pptpt != 3014 (*((pt_entry_t *)(PROCESS_PAGE_TBLS_BASE 3015 + (PROCESS_PAGE_TBLS_BASE >> (PGSHIFT - 2)) + 3016 (PROCESS_PAGE_TBLS_BASE >> PDSHIFT))) & PG_FRAME)) { 3017 printf("pmap pagetable = P%08lx current = P%08x ", 3018 pmap->pm_pptpt, (*((pt_entry_t *)(PROCESS_PAGE_TBLS_BASE 3019 + (PROCESS_PAGE_TBLS_BASE >> (PGSHIFT - 2)) + 3020 (PROCESS_PAGE_TBLS_BASE >> PDSHIFT))) & 3021 PG_FRAME)); 3022 printf("pptpt=%lx\n", p->p_vmspace->vm_map.pmap->pm_pptpt); 3023 panic("pmap_pte: current and pmap mismatch\n"); 3024 } 3025 #endif 3026 3027 ptp = (pt_entry_t *)ALT_PAGE_TBLS_BASE; 3028 pmap_map_in_l1(p->p_vmspace->vm_map.pmap, ALT_PAGE_TBLS_BASE, 3029 pmap->pm_pptpt, FALSE); 3030 cpu_tlb_flushD(); 3031 cpu_cpwait(); 3032 } 3033 PDEBUG(10, printf("page tables base = %p offset=%lx\n", ptp, 3034 ((va >> (PGSHIFT-2)) & ~3))); 3035 result = (pt_entry_t *)((char *)ptp + ((va >> (PGSHIFT-2)) & ~3)); 3036 return(result); 3037 } 3038 3039 /* 3040 * Routine: pmap_extract 3041 * Function: 3042 * Extract the physical page address associated 3043 * with the given map/virtual_address pair. 3044 */ 3045 boolean_t 3046 pmap_extract(pmap, va, pap) 3047 struct pmap *pmap; 3048 vaddr_t va; 3049 paddr_t *pap; 3050 { 3051 pd_entry_t *pde; 3052 pt_entry_t *pte, *ptes; 3053 paddr_t pa; 3054 boolean_t rv = TRUE; 3055 3056 PDEBUG(5, printf("pmap_extract: pmap=%p, va=V%08lx\n", pmap, va)); 3057 3058 /* 3059 * Get the pte for this virtual address. 3060 */ 3061 pde = pmap_pde(pmap, va); 3062 ptes = pmap_map_ptes(pmap); 3063 pte = &ptes[arm_byte_to_page(va)]; 3064 3065 if (pmap_pde_section(pde)) { 3066 pa = (*pde & PD_MASK) | (va & (L1_SEC_SIZE - 1)); 3067 goto out; 3068 } else if (pmap_pde_page(pde) == 0 || pmap_pte_v(pte) == 0) { 3069 rv = FALSE; 3070 goto out; 3071 } 3072 3073 if ((*pte & L2_MASK) == L2_LPAGE) { 3074 /* Extract the physical address from the pte */ 3075 pa = *pte & ~(L2_LPAGE_SIZE - 1); 3076 3077 PDEBUG(5, printf("pmap_extract: LPAGE pa = P%08lx\n", 3078 (pa | (va & (L2_LPAGE_SIZE - 1))))); 3079 3080 if (pap != NULL) 3081 *pap = pa | (va & (L2_LPAGE_SIZE - 1)); 3082 goto out; 3083 } 3084 3085 /* Extract the physical address from the pte */ 3086 pa = pmap_pte_pa(pte); 3087 3088 PDEBUG(5, printf("pmap_extract: SPAGE pa = P%08lx\n", 3089 (pa | (va & ~PG_FRAME)))); 3090 3091 if (pap != NULL) 3092 *pap = pa | (va & ~PG_FRAME); 3093 out: 3094 pmap_unmap_ptes(pmap); 3095 return (rv); 3096 } 3097 3098 3099 /* 3100 * Copy the range specified by src_addr/len from the source map to the 3101 * range dst_addr/len in the destination map. 3102 * 3103 * This routine is only advisory and need not do anything. 3104 */ 3105 3106 void 3107 pmap_copy(dst_pmap, src_pmap, dst_addr, len, src_addr) 3108 struct pmap *dst_pmap; 3109 struct pmap *src_pmap; 3110 vaddr_t dst_addr; 3111 vsize_t len; 3112 vaddr_t src_addr; 3113 { 3114 PDEBUG(0, printf("pmap_copy(%p, %p, %lx, %lx, %lx)\n", 3115 dst_pmap, src_pmap, dst_addr, len, src_addr)); 3116 } 3117 3118 #if defined(PMAP_DEBUG) 3119 void 3120 pmap_dump_pvlist(phys, m) 3121 vaddr_t phys; 3122 char *m; 3123 { 3124 struct vm_page *pg; 3125 struct pv_entry *pv; 3126 3127 if ((pg = PHYS_TO_VM_PAGE(phys)) == NULL) { 3128 printf("INVALID PA\n"); 3129 return; 3130 } 3131 simple_lock(&pg->mdpage.pvh_slock); 3132 printf("%s %08lx:", m, phys); 3133 if (pg->mdpage.pvh_list == NULL) { 3134 printf(" no mappings\n"); 3135 return; 3136 } 3137 3138 for (pv = pg->mdpage.pvh_list; pv; pv = pv->pv_next) 3139 printf(" pmap %p va %08lx flags %08x", pv->pv_pmap, 3140 pv->pv_va, pv->pv_flags); 3141 3142 printf("\n"); 3143 simple_unlock(&pg->mdpage.pvh_slock); 3144 } 3145 3146 #endif /* PMAP_DEBUG */ 3147 3148 __inline static boolean_t 3149 pmap_testbit(pg, setbits) 3150 struct vm_page *pg; 3151 unsigned int setbits; 3152 { 3153 3154 PDEBUG(1, printf("pmap_testbit: pa=%08lx set=%08x\n", 3155 VM_PAGE_TO_PHYS(pg), setbits)); 3156 3157 /* 3158 * Check saved info only 3159 */ 3160 if (pg->mdpage.pvh_attrs & setbits) { 3161 PDEBUG(0, printf("pmap_attributes = %02x\n", 3162 pg->mdpage.pvh_attrs)); 3163 return(TRUE); 3164 } 3165 3166 return(FALSE); 3167 } 3168 3169 static pt_entry_t * 3170 pmap_map_ptes(struct pmap *pmap) 3171 { 3172 struct proc *p; 3173 3174 /* the kernel's pmap is always accessible */ 3175 if (pmap == pmap_kernel()) { 3176 return (pt_entry_t *)PROCESS_PAGE_TBLS_BASE ; 3177 } 3178 3179 if (pmap_is_curpmap(pmap)) { 3180 simple_lock(&pmap->pm_obj.vmobjlock); 3181 return (pt_entry_t *)PROCESS_PAGE_TBLS_BASE; 3182 } 3183 3184 p = curproc; 3185 3186 if (p == NULL) 3187 p = &proc0; 3188 3189 /* need to lock both curpmap and pmap: use ordered locking */ 3190 if ((unsigned) pmap < (unsigned) curproc->p_vmspace->vm_map.pmap) { 3191 simple_lock(&pmap->pm_obj.vmobjlock); 3192 simple_lock(&curproc->p_vmspace->vm_map.pmap->pm_obj.vmobjlock); 3193 } else { 3194 simple_lock(&curproc->p_vmspace->vm_map.pmap->pm_obj.vmobjlock); 3195 simple_lock(&pmap->pm_obj.vmobjlock); 3196 } 3197 3198 pmap_map_in_l1(p->p_vmspace->vm_map.pmap, ALT_PAGE_TBLS_BASE, 3199 pmap->pm_pptpt, FALSE); 3200 cpu_tlb_flushD(); 3201 cpu_cpwait(); 3202 return (pt_entry_t *)ALT_PAGE_TBLS_BASE; 3203 } 3204 3205 /* 3206 * pmap_unmap_ptes: unlock the PTE mapping of "pmap" 3207 */ 3208 3209 static void 3210 pmap_unmap_ptes(pmap) 3211 struct pmap *pmap; 3212 { 3213 if (pmap == pmap_kernel()) { 3214 return; 3215 } 3216 if (pmap_is_curpmap(pmap)) { 3217 simple_unlock(&pmap->pm_obj.vmobjlock); 3218 } else { 3219 simple_unlock(&pmap->pm_obj.vmobjlock); 3220 simple_unlock(&curproc->p_vmspace->vm_map.pmap->pm_obj.vmobjlock); 3221 } 3222 } 3223 3224 /* 3225 * Modify pte bits for all ptes corresponding to the given physical address. 3226 * We use `maskbits' rather than `clearbits' because we're always passing 3227 * constants and the latter would require an extra inversion at run-time. 3228 */ 3229 3230 static void 3231 pmap_clearbit(pg, maskbits) 3232 struct vm_page *pg; 3233 unsigned int maskbits; 3234 { 3235 struct pv_entry *pv; 3236 pt_entry_t *pte; 3237 vaddr_t va; 3238 int tlbentry; 3239 3240 PDEBUG(1, printf("pmap_clearbit: pa=%08lx mask=%08x\n", 3241 VM_PAGE_TO_PHYS(pg), maskbits)); 3242 3243 tlbentry = 0; 3244 3245 PMAP_HEAD_TO_MAP_LOCK(); 3246 simple_lock(&pg->mdpage.pvh_slock); 3247 3248 /* 3249 * Clear saved attributes (modify, reference) 3250 */ 3251 pg->mdpage.pvh_attrs &= ~maskbits; 3252 3253 if (pg->mdpage.pvh_list == NULL) { 3254 simple_unlock(&pg->mdpage.pvh_slock); 3255 PMAP_HEAD_TO_MAP_UNLOCK(); 3256 return; 3257 } 3258 3259 /* 3260 * Loop over all current mappings setting/clearing as appropos 3261 */ 3262 for (pv = pg->mdpage.pvh_list; pv; pv = pv->pv_next) { 3263 va = pv->pv_va; 3264 pv->pv_flags &= ~maskbits; 3265 pte = pmap_pte(pv->pv_pmap, va); 3266 KASSERT(pte != NULL); 3267 if (maskbits & (PT_Wr|PT_M)) { 3268 if ((pv->pv_flags & PT_NC)) { 3269 /* 3270 * Entry is not cacheable: reenable 3271 * the cache, nothing to flush 3272 * 3273 * Don't turn caching on again if this 3274 * is a modified emulation. This 3275 * would be inconsitent with the 3276 * settings created by 3277 * pmap_vac_me_harder(). 3278 * 3279 * There's no need to call 3280 * pmap_vac_me_harder() here: all 3281 * pages are loosing their write 3282 * permission. 3283 * 3284 */ 3285 if (maskbits & PT_Wr) { 3286 *pte |= pte_cache_mode; 3287 pv->pv_flags &= ~PT_NC; 3288 } 3289 } else if (pmap_is_curpmap(pv->pv_pmap)) 3290 /* 3291 * Entry is cacheable: check if pmap is 3292 * current if it is flush it, 3293 * otherwise it won't be in the cache 3294 */ 3295 cpu_idcache_wbinv_range(pv->pv_va, NBPG); 3296 3297 /* make the pte read only */ 3298 *pte &= ~PT_AP(AP_W); 3299 } 3300 3301 if (maskbits & PT_H) 3302 *pte = (*pte & ~L2_MASK) | L2_INVAL; 3303 3304 if (pmap_is_curpmap(pv->pv_pmap)) 3305 /* 3306 * if we had cacheable pte's we'd clean the 3307 * pte out to memory here 3308 * 3309 * flush tlb entry as it's in the current pmap 3310 */ 3311 cpu_tlb_flushID_SE(pv->pv_va); 3312 } 3313 cpu_cpwait(); 3314 3315 simple_unlock(&pg->mdpage.pvh_slock); 3316 PMAP_HEAD_TO_MAP_UNLOCK(); 3317 } 3318 3319 3320 boolean_t 3321 pmap_clear_modify(pg) 3322 struct vm_page *pg; 3323 { 3324 boolean_t rv; 3325 3326 PDEBUG(0, printf("pmap_clear_modify pa=%08lx\n", VM_PAGE_TO_PHYS(pg))); 3327 rv = pmap_testbit(pg, PT_M); 3328 pmap_clearbit(pg, PT_M); 3329 return rv; 3330 } 3331 3332 3333 boolean_t 3334 pmap_clear_reference(pg) 3335 struct vm_page *pg; 3336 { 3337 boolean_t rv; 3338 3339 PDEBUG(0, printf("pmap_clear_reference pa=%08lx\n", 3340 VM_PAGE_TO_PHYS(pg))); 3341 rv = pmap_testbit(pg, PT_H); 3342 pmap_clearbit(pg, PT_H); 3343 return rv; 3344 } 3345 3346 3347 void 3348 pmap_copy_on_write(pg) 3349 struct vm_page *pg; 3350 { 3351 PDEBUG(0, printf("pmap_copy_on_write pa=%08lx\n", VM_PAGE_TO_PHYS(pg))); 3352 pmap_clearbit(pg, PT_Wr); 3353 } 3354 3355 3356 boolean_t 3357 pmap_is_modified(pg) 3358 struct vm_page *pg; 3359 { 3360 boolean_t result; 3361 3362 result = pmap_testbit(pg, PT_M); 3363 PDEBUG(1, printf("pmap_is_modified pa=%08lx %x\n", 3364 VM_PAGE_TO_PHYS(pg), result)); 3365 return (result); 3366 } 3367 3368 3369 boolean_t 3370 pmap_is_referenced(pg) 3371 struct vm_page *pg; 3372 { 3373 boolean_t result; 3374 3375 result = pmap_testbit(pg, PT_H); 3376 PDEBUG(0, printf("pmap_is_referenced pa=%08lx %x\n", 3377 VM_PAGE_TO_PHYS(pg), result)); 3378 return (result); 3379 } 3380 3381 3382 int 3383 pmap_modified_emulation(pmap, va) 3384 struct pmap *pmap; 3385 vaddr_t va; 3386 { 3387 pt_entry_t *pte; 3388 paddr_t pa; 3389 struct vm_page *pg; 3390 u_int flags; 3391 3392 PDEBUG(2, printf("pmap_modified_emulation\n")); 3393 3394 /* Get the pte */ 3395 pte = pmap_pte(pmap, va); 3396 if (!pte) { 3397 PDEBUG(2, printf("no pte\n")); 3398 return(0); 3399 } 3400 3401 PDEBUG(1, printf("*pte=%08x\n", *pte)); 3402 3403 /* Check for a zero pte */ 3404 if (*pte == 0) 3405 return(0); 3406 3407 /* This can happen if user code tries to access kernel memory. */ 3408 if ((*pte & PT_AP(AP_W)) != 0) 3409 return (0); 3410 3411 /* Extract the physical address of the page */ 3412 pa = pmap_pte_pa(pte); 3413 if ((pg = PHYS_TO_VM_PAGE(pa)) == NULL) 3414 return(0); 3415 3416 /* Get the current flags for this page. */ 3417 PMAP_HEAD_TO_MAP_LOCK(); 3418 simple_lock(&pg->mdpage.pvh_slock); 3419 3420 flags = pmap_modify_pv(pmap, va, pg, 0, 0); 3421 PDEBUG(2, printf("pmap_modified_emulation: flags = %08x\n", flags)); 3422 3423 /* 3424 * Do the flags say this page is writable ? If not then it is a 3425 * genuine write fault. If yes then the write fault is our fault 3426 * as we did not reflect the write access in the PTE. Now we know 3427 * a write has occurred we can correct this and also set the 3428 * modified bit 3429 */ 3430 if (~flags & PT_Wr) { 3431 simple_unlock(&pg->mdpage.pvh_slock); 3432 PMAP_HEAD_TO_MAP_UNLOCK(); 3433 return(0); 3434 } 3435 3436 PDEBUG(0, printf("pmap_modified_emulation: Got a hit va=%08lx, pte = %p (%08x)\n", 3437 va, pte, *pte)); 3438 pg->mdpage.pvh_attrs |= PT_H | PT_M; 3439 3440 /* 3441 * Re-enable write permissions for the page. No need to call 3442 * pmap_vac_me_harder(), since this is just a 3443 * modified-emulation fault, and the PT_Wr bit isn't changing. We've 3444 * already set the cacheable bits based on the assumption that we 3445 * can write to this page. 3446 */ 3447 *pte = (*pte & ~L2_MASK) | L2_SPAGE | PT_AP(AP_W); 3448 PDEBUG(0, printf("->(%08x)\n", *pte)); 3449 3450 simple_unlock(&pg->mdpage.pvh_slock); 3451 PMAP_HEAD_TO_MAP_UNLOCK(); 3452 /* Return, indicating the problem has been dealt with */ 3453 cpu_tlb_flushID_SE(va); 3454 cpu_cpwait(); 3455 return(1); 3456 } 3457 3458 3459 int 3460 pmap_handled_emulation(pmap, va) 3461 struct pmap *pmap; 3462 vaddr_t va; 3463 { 3464 pt_entry_t *pte; 3465 paddr_t pa; 3466 struct vm_page *pg; 3467 3468 PDEBUG(2, printf("pmap_handled_emulation\n")); 3469 3470 /* Get the pte */ 3471 pte = pmap_pte(pmap, va); 3472 if (!pte) { 3473 PDEBUG(2, printf("no pte\n")); 3474 return(0); 3475 } 3476 3477 PDEBUG(1, printf("*pte=%08x\n", *pte)); 3478 3479 /* Check for a zero pte */ 3480 if (*pte == 0) 3481 return(0); 3482 3483 /* This can happen if user code tries to access kernel memory. */ 3484 if ((*pte & L2_MASK) != L2_INVAL) 3485 return (0); 3486 3487 /* Extract the physical address of the page */ 3488 pa = pmap_pte_pa(pte); 3489 if ((pg = PHYS_TO_VM_PAGE(pa)) == NULL) 3490 return (0); 3491 3492 /* 3493 * Ok we just enable the pte and mark the attibs as handled 3494 */ 3495 PDEBUG(0, printf("pmap_handled_emulation: Got a hit va=%08lx pte = %p (%08x)\n", 3496 va, pte, *pte)); 3497 pg->mdpage.pvh_attrs |= PT_H; 3498 *pte = (*pte & ~L2_MASK) | L2_SPAGE; 3499 PDEBUG(0, printf("->(%08x)\n", *pte)); 3500 3501 /* Return, indicating the problem has been dealt with */ 3502 cpu_tlb_flushID_SE(va); 3503 cpu_cpwait(); 3504 return(1); 3505 } 3506 3507 3508 3509 3510 /* 3511 * pmap_collect: free resources held by a pmap 3512 * 3513 * => optional function. 3514 * => called when a process is swapped out to free memory. 3515 */ 3516 3517 void 3518 pmap_collect(pmap) 3519 struct pmap *pmap; 3520 { 3521 } 3522 3523 /* 3524 * Routine: pmap_procwr 3525 * 3526 * Function: 3527 * Synchronize caches corresponding to [addr, addr+len) in p. 3528 * 3529 */ 3530 void 3531 pmap_procwr(p, va, len) 3532 struct proc *p; 3533 vaddr_t va; 3534 int len; 3535 { 3536 /* We only need to do anything if it is the current process. */ 3537 if (p == curproc) 3538 cpu_icache_sync_range(va, len); 3539 } 3540 /* 3541 * PTP functions 3542 */ 3543 3544 /* 3545 * pmap_steal_ptp: Steal a PTP from somewhere else. 3546 * 3547 * This is just a placeholder, for now we never steal. 3548 */ 3549 3550 static struct vm_page * 3551 pmap_steal_ptp(struct pmap *pmap, vaddr_t va) 3552 { 3553 return (NULL); 3554 } 3555 3556 /* 3557 * pmap_get_ptp: get a PTP (if there isn't one, allocate a new one) 3558 * 3559 * => pmap should NOT be pmap_kernel() 3560 * => pmap should be locked 3561 */ 3562 3563 static struct vm_page * 3564 pmap_get_ptp(struct pmap *pmap, vaddr_t va, boolean_t just_try) 3565 { 3566 struct vm_page *ptp; 3567 3568 if (pmap_pde_page(pmap_pde(pmap, va))) { 3569 3570 /* valid... check hint (saves us a PA->PG lookup) */ 3571 #if 0 3572 if (pmap->pm_ptphint && 3573 ((unsigned)pmap_pde(pmap, va) & PG_FRAME) == 3574 VM_PAGE_TO_PHYS(pmap->pm_ptphint)) 3575 return (pmap->pm_ptphint); 3576 #endif 3577 ptp = uvm_pagelookup(&pmap->pm_obj, va); 3578 #ifdef DIAGNOSTIC 3579 if (ptp == NULL) 3580 panic("pmap_get_ptp: unmanaged user PTP"); 3581 #endif 3582 // pmap->pm_ptphint = ptp; 3583 return(ptp); 3584 } 3585 3586 /* allocate a new PTP (updates ptphint) */ 3587 return(pmap_alloc_ptp(pmap, va, just_try)); 3588 } 3589 3590 /* 3591 * pmap_alloc_ptp: allocate a PTP for a PMAP 3592 * 3593 * => pmap should already be locked by caller 3594 * => we use the ptp's wire_count to count the number of active mappings 3595 * in the PTP (we start it at one to prevent any chance this PTP 3596 * will ever leak onto the active/inactive queues) 3597 */ 3598 3599 /*__inline */ static struct vm_page * 3600 pmap_alloc_ptp(struct pmap *pmap, vaddr_t va, boolean_t just_try) 3601 { 3602 struct vm_page *ptp; 3603 3604 ptp = uvm_pagealloc(&pmap->pm_obj, va, NULL, 3605 UVM_PGA_USERESERVE|UVM_PGA_ZERO); 3606 if (ptp == NULL) { 3607 if (just_try) 3608 return (NULL); 3609 3610 ptp = pmap_steal_ptp(pmap, va); 3611 3612 if (ptp == NULL) 3613 return (NULL); 3614 /* Stole a page, zero it. */ 3615 pmap_zero_page(VM_PAGE_TO_PHYS(ptp)); 3616 } 3617 3618 /* got one! */ 3619 ptp->flags &= ~PG_BUSY; /* never busy */ 3620 ptp->wire_count = 1; /* no mappings yet */ 3621 pmap_map_in_l1(pmap, va, VM_PAGE_TO_PHYS(ptp), TRUE); 3622 pmap->pm_stats.resident_count++; /* count PTP as resident */ 3623 // pmap->pm_ptphint = ptp; 3624 return (ptp); 3625 } 3626 3627 /* End of pmap.c */ 3628
Indexes created Fri Sep 26 20:09:58 GMT 2025