uvm_page.c revision 1.226 1 /* $NetBSD: uvm_page.c,v 1.226 2020/02/23 15:46:43 ad Exp $ */
2
3 /*-
4 * Copyright (c) 2019, 2020 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Andrew Doran.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 /*
33 * Copyright (c) 1997 Charles D. Cranor and Washington University.
34 * Copyright (c) 1991, 1993, The Regents of the University of California.
35 *
36 * All rights reserved.
37 *
38 * This code is derived from software contributed to Berkeley by
39 * The Mach Operating System project at Carnegie-Mellon University.
40 *
41 * Redistribution and use in source and binary forms, with or without
42 * modification, are permitted provided that the following conditions
43 * are met:
44 * 1. Redistributions of source code must retain the above copyright
45 * notice, this list of conditions and the following disclaimer.
46 * 2. Redistributions in binary form must reproduce the above copyright
47 * notice, this list of conditions and the following disclaimer in the
48 * documentation and/or other materials provided with the distribution.
49 * 3. Neither the name of the University nor the names of its contributors
50 * may be used to endorse or promote products derived from this software
51 * without specific prior written permission.
52 *
53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63 * SUCH DAMAGE.
64 *
65 * @(#)vm_page.c 8.3 (Berkeley) 3/21/94
66 * from: Id: uvm_page.c,v 1.1.2.18 1998/02/06 05:24:42 chs Exp
67 *
68 *
69 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
70 * All rights reserved.
71 *
72 * Permission to use, copy, modify and distribute this software and
73 * its documentation is hereby granted, provided that both the copyright
74 * notice and this permission notice appear in all copies of the
75 * software, derivative works or modified versions, and any portions
76 * thereof, and that both notices appear in supporting documentation.
77 *
78 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
79 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
80 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
81 *
82 * Carnegie Mellon requests users of this software to return to
83 *
84 * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU
85 * School of Computer Science
86 * Carnegie Mellon University
87 * Pittsburgh PA 15213-3890
88 *
89 * any improvements or extensions that they make and grant Carnegie the
90 * rights to redistribute these changes.
91 */
92
93 /*
94 * uvm_page.c: page ops.
95 */
96
97 #include <sys/cdefs.h>
98 __KERNEL_RCSID(0, "$NetBSD: uvm_page.c,v 1.226 2020/02/23 15:46:43 ad Exp $");
99
100 #include "opt_ddb.h"
101 #include "opt_uvm.h"
102 #include "opt_uvmhist.h"
103 #include "opt_readahead.h"
104
105 #include <sys/param.h>
106 #include <sys/systm.h>
107 #include <sys/sched.h>
108 #include <sys/kernel.h>
109 #include <sys/vnode.h>
110 #include <sys/proc.h>
111 #include <sys/radixtree.h>
112 #include <sys/atomic.h>
113 #include <sys/cpu.h>
114 #include <sys/extent.h>
115
116 #include <uvm/uvm.h>
117 #include <uvm/uvm_ddb.h>
118 #include <uvm/uvm_pdpolicy.h>
119 #include <uvm/uvm_pgflcache.h>
120
121 /*
122 * Some supported CPUs in a given architecture don't support all
123 * of the things necessary to do idle page zero'ing efficiently.
124 * We therefore provide a way to enable it from machdep code here.
125 */
126 bool vm_page_zero_enable = false;
127
128 /*
129 * number of pages per-CPU to reserve for the kernel.
130 */
131 #ifndef UVM_RESERVED_PAGES_PER_CPU
132 #define UVM_RESERVED_PAGES_PER_CPU 5
133 #endif
134 int vm_page_reserve_kernel = UVM_RESERVED_PAGES_PER_CPU;
135
136 /*
137 * physical memory size;
138 */
139 psize_t physmem;
140
141 /*
142 * local variables
143 */
144
145 /*
146 * these variables record the values returned by vm_page_bootstrap,
147 * for debugging purposes. The implementation of uvm_pageboot_alloc
148 * and pmap_startup here also uses them internally.
149 */
150
151 static vaddr_t virtual_space_start;
152 static vaddr_t virtual_space_end;
153
154 /*
155 * we allocate an initial number of page colors in uvm_page_init(),
156 * and remember them. We may re-color pages as cache sizes are
157 * discovered during the autoconfiguration phase. But we can never
158 * free the initial set of buckets, since they are allocated using
159 * uvm_pageboot_alloc().
160 */
161
162 static size_t recolored_pages_memsize /* = 0 */;
163 static char *recolored_pages_mem;
164
165 /*
166 * freelist locks - one per bucket.
167 */
168
169 union uvm_freelist_lock uvm_freelist_locks[PGFL_MAX_BUCKETS]
170 __cacheline_aligned;
171
172 /*
173 * basic NUMA information.
174 */
175
176 static struct uvm_page_numa_region {
177 struct uvm_page_numa_region *next;
178 paddr_t start;
179 paddr_t size;
180 u_int numa_id;
181 } *uvm_page_numa_region;
182
183 #ifdef DEBUG
184 kmutex_t uvm_zerochecklock __cacheline_aligned;
185 vaddr_t uvm_zerocheckkva;
186 #endif /* DEBUG */
187
188 /*
189 * These functions are reserved for uvm(9) internal use and are not
190 * exported in the header file uvm_physseg.h
191 *
192 * Thus they are redefined here.
193 */
194 void uvm_physseg_init_seg(uvm_physseg_t, struct vm_page *);
195 void uvm_physseg_seg_chomp_slab(uvm_physseg_t, struct vm_page *, size_t);
196
197 /* returns a pgs array */
198 struct vm_page *uvm_physseg_seg_alloc_from_slab(uvm_physseg_t, size_t);
199
200 /*
201 * inline functions
202 */
203
204 /*
205 * uvm_pageinsert: insert a page in the object.
206 *
207 * => caller must lock object
208 * => call should have already set pg's object and offset pointers
209 * and bumped the version counter
210 */
211
212 static inline void
213 uvm_pageinsert_object(struct uvm_object *uobj, struct vm_page *pg)
214 {
215
216 KASSERT(uobj == pg->uobject);
217 KASSERT(rw_write_held(uobj->vmobjlock));
218 KASSERT((pg->flags & PG_TABLED) == 0);
219
220 if ((pg->flags & PG_STAT) != 0) {
221 /* Cannot use uvm_pagegetdirty(): not yet in radix tree. */
222 const unsigned int status = pg->flags & (PG_CLEAN | PG_DIRTY);
223 const bool isaobj = (pg->flags & PG_AOBJ) != 0;
224
225 if (!isaobj) {
226 KASSERT((pg->flags & PG_FILE) != 0);
227 if (uobj->uo_npages == 0) {
228 vhold((struct vnode *)uobj);
229 }
230 kpreempt_disable();
231 if (UVM_OBJ_IS_VTEXT(uobj)) {
232 CPU_COUNT(CPU_COUNT_EXECPAGES, 1);
233 } else {
234 CPU_COUNT(CPU_COUNT_FILEPAGES, 1);
235 }
236 CPU_COUNT(CPU_COUNT_FILEUNKNOWN + status, 1);
237 } else {
238 kpreempt_disable();
239 CPU_COUNT(CPU_COUNT_ANONPAGES, 1);
240 CPU_COUNT(CPU_COUNT_ANONUNKNOWN + status, 1);
241 }
242 kpreempt_enable();
243 }
244 pg->flags |= PG_TABLED;
245 uobj->uo_npages++;
246 }
247
248 static inline int
249 uvm_pageinsert_tree(struct uvm_object *uobj, struct vm_page *pg)
250 {
251 const uint64_t idx = pg->offset >> PAGE_SHIFT;
252 int error;
253
254 error = radix_tree_insert_node(&uobj->uo_pages, idx, pg);
255 if (error != 0) {
256 return error;
257 }
258 if ((pg->flags & PG_CLEAN) == 0) {
259 radix_tree_set_tag(&uobj->uo_pages, idx, UVM_PAGE_DIRTY_TAG);
260 }
261 KASSERT(((pg->flags & PG_CLEAN) == 0) ==
262 radix_tree_get_tag(&uobj->uo_pages, idx, UVM_PAGE_DIRTY_TAG));
263 return 0;
264 }
265
266 /*
267 * uvm_page_remove: remove page from object.
268 *
269 * => caller must lock object
270 */
271
272 static inline void
273 uvm_pageremove_object(struct uvm_object *uobj, struct vm_page *pg)
274 {
275
276 KASSERT(uobj == pg->uobject);
277 KASSERT(rw_write_held(uobj->vmobjlock));
278 KASSERT(pg->flags & PG_TABLED);
279
280 if ((pg->flags & PG_STAT) != 0) {
281 /* Cannot use uvm_pagegetdirty(): no longer in radix tree. */
282 const unsigned int status = pg->flags & (PG_CLEAN | PG_DIRTY);
283 const bool isaobj = (pg->flags & PG_AOBJ) != 0;
284
285 if (!isaobj) {
286 KASSERT((pg->flags & PG_FILE) != 0);
287 if (uobj->uo_npages == 1) {
288 holdrele((struct vnode *)uobj);
289 }
290 kpreempt_disable();
291 if (UVM_OBJ_IS_VTEXT(uobj)) {
292 CPU_COUNT(CPU_COUNT_EXECPAGES, -1);
293 } else {
294 CPU_COUNT(CPU_COUNT_FILEPAGES, -1);
295 }
296 CPU_COUNT(CPU_COUNT_FILEUNKNOWN + status, -1);
297 } else {
298 kpreempt_disable();
299 CPU_COUNT(CPU_COUNT_ANONPAGES, -1);
300 CPU_COUNT(CPU_COUNT_ANONUNKNOWN + status, -1);
301 }
302 kpreempt_enable();
303 }
304 uobj->uo_npages--;
305 pg->flags &= ~PG_TABLED;
306 pg->uobject = NULL;
307 }
308
309 static inline void
310 uvm_pageremove_tree(struct uvm_object *uobj, struct vm_page *pg)
311 {
312 struct vm_page *opg __unused;
313
314 opg = radix_tree_remove_node(&uobj->uo_pages, pg->offset >> PAGE_SHIFT);
315 KASSERT(pg == opg);
316 }
317
318 static void
319 uvm_page_init_bucket(struct pgfreelist *pgfl, struct pgflbucket *pgb, int num)
320 {
321 int i;
322
323 pgb->pgb_nfree = 0;
324 for (i = 0; i < uvmexp.ncolors; i++) {
325 LIST_INIT(&pgb->pgb_colors[i]);
326 }
327 pgfl->pgfl_buckets[num] = pgb;
328 }
329
330 /*
331 * uvm_page_init: init the page system. called from uvm_init().
332 *
333 * => we return the range of kernel virtual memory in kvm_startp/kvm_endp
334 */
335
336 void
337 uvm_page_init(vaddr_t *kvm_startp, vaddr_t *kvm_endp)
338 {
339 static struct uvm_cpu boot_cpu __cacheline_aligned;
340 psize_t freepages, pagecount, bucketsize, n;
341 struct pgflbucket *pgb;
342 struct vm_page *pagearray;
343 char *bucketarray;
344 uvm_physseg_t bank;
345 int fl, b;
346
347 KASSERT(ncpu <= 1);
348
349 /*
350 * init the page queues and free page queue locks, except the
351 * free list; we allocate that later (with the initial vm_page
352 * structures).
353 */
354
355 curcpu()->ci_data.cpu_uvm = &boot_cpu;
356 uvmpdpol_init();
357 for (b = 0; b < __arraycount(uvm_freelist_locks); b++) {
358 mutex_init(&uvm_freelist_locks[b].lock, MUTEX_DEFAULT, IPL_VM);
359 }
360
361 /*
362 * allocate vm_page structures.
363 */
364
365 /*
366 * sanity check:
367 * before calling this function the MD code is expected to register
368 * some free RAM with the uvm_page_physload() function. our job
369 * now is to allocate vm_page structures for this memory.
370 */
371
372 if (uvm_physseg_get_last() == UVM_PHYSSEG_TYPE_INVALID)
373 panic("uvm_page_bootstrap: no memory pre-allocated");
374
375 /*
376 * first calculate the number of free pages...
377 *
378 * note that we use start/end rather than avail_start/avail_end.
379 * this allows us to allocate extra vm_page structures in case we
380 * want to return some memory to the pool after booting.
381 */
382
383 freepages = 0;
384
385 for (bank = uvm_physseg_get_first();
386 uvm_physseg_valid_p(bank) ;
387 bank = uvm_physseg_get_next(bank)) {
388 freepages += (uvm_physseg_get_end(bank) - uvm_physseg_get_start(bank));
389 }
390
391 /*
392 * Let MD code initialize the number of colors, or default
393 * to 1 color if MD code doesn't care.
394 */
395 if (uvmexp.ncolors == 0)
396 uvmexp.ncolors = 1;
397 uvmexp.colormask = uvmexp.ncolors - 1;
398 KASSERT((uvmexp.colormask & uvmexp.ncolors) == 0);
399
400 /* We always start with only 1 bucket. */
401 uvm.bucketcount = 1;
402
403 /*
404 * we now know we have (PAGE_SIZE * freepages) bytes of memory we can
405 * use. for each page of memory we use we need a vm_page structure.
406 * thus, the total number of pages we can use is the total size of
407 * the memory divided by the PAGE_SIZE plus the size of the vm_page
408 * structure. we add one to freepages as a fudge factor to avoid
409 * truncation errors (since we can only allocate in terms of whole
410 * pages).
411 */
412 pagecount = ((freepages + 1) << PAGE_SHIFT) /
413 (PAGE_SIZE + sizeof(struct vm_page));
414 bucketsize = offsetof(struct pgflbucket, pgb_colors[uvmexp.ncolors]);
415 bucketsize = roundup2(bucketsize, coherency_unit);
416 bucketarray = (void *)uvm_pageboot_alloc(
417 bucketsize * VM_NFREELIST +
418 pagecount * sizeof(struct vm_page));
419 pagearray = (struct vm_page *)
420 (bucketarray + bucketsize * VM_NFREELIST);
421
422 for (fl = 0; fl < VM_NFREELIST; fl++) {
423 pgb = (struct pgflbucket *)(bucketarray + bucketsize * fl);
424 uvm_page_init_bucket(&uvm.page_free[fl], pgb, 0);
425 }
426 memset(pagearray, 0, pagecount * sizeof(struct vm_page));
427
428 /*
429 * init the freelist cache in the disabled state.
430 */
431 uvm_pgflcache_init();
432
433 /*
434 * init the vm_page structures and put them in the correct place.
435 */
436 /* First init the extent */
437
438 for (bank = uvm_physseg_get_first(),
439 uvm_physseg_seg_chomp_slab(bank, pagearray, pagecount);
440 uvm_physseg_valid_p(bank);
441 bank = uvm_physseg_get_next(bank)) {
442
443 n = uvm_physseg_get_end(bank) - uvm_physseg_get_start(bank);
444 uvm_physseg_seg_alloc_from_slab(bank, n);
445 uvm_physseg_init_seg(bank, pagearray);
446
447 /* set up page array pointers */
448 pagearray += n;
449 pagecount -= n;
450 }
451
452 /*
453 * pass up the values of virtual_space_start and
454 * virtual_space_end (obtained by uvm_pageboot_alloc) to the upper
455 * layers of the VM.
456 */
457
458 *kvm_startp = round_page(virtual_space_start);
459 *kvm_endp = trunc_page(virtual_space_end);
460 #ifdef DEBUG
461 /*
462 * steal kva for uvm_pagezerocheck().
463 */
464 uvm_zerocheckkva = *kvm_startp;
465 *kvm_startp += PAGE_SIZE;
466 mutex_init(&uvm_zerochecklock, MUTEX_DEFAULT, IPL_VM);
467 #endif /* DEBUG */
468
469 /*
470 * init various thresholds.
471 */
472
473 uvmexp.reserve_pagedaemon = 1;
474 uvmexp.reserve_kernel = vm_page_reserve_kernel;
475
476 /*
477 * done!
478 */
479
480 uvm.page_init_done = true;
481 }
482
483 /*
484 * uvm_pgfl_lock: lock all freelist buckets
485 */
486
487 void
488 uvm_pgfl_lock(void)
489 {
490 int i;
491
492 for (i = 0; i < __arraycount(uvm_freelist_locks); i++) {
493 mutex_spin_enter(&uvm_freelist_locks[i].lock);
494 }
495 }
496
497 /*
498 * uvm_pgfl_unlock: unlock all freelist buckets
499 */
500
501 void
502 uvm_pgfl_unlock(void)
503 {
504 int i;
505
506 for (i = 0; i < __arraycount(uvm_freelist_locks); i++) {
507 mutex_spin_exit(&uvm_freelist_locks[i].lock);
508 }
509 }
510
511 /*
512 * uvm_setpagesize: set the page size
513 *
514 * => sets page_shift and page_mask from uvmexp.pagesize.
515 */
516
517 void
518 uvm_setpagesize(void)
519 {
520
521 /*
522 * If uvmexp.pagesize is 0 at this point, we expect PAGE_SIZE
523 * to be a constant (indicated by being a non-zero value).
524 */
525 if (uvmexp.pagesize == 0) {
526 if (PAGE_SIZE == 0)
527 panic("uvm_setpagesize: uvmexp.pagesize not set");
528 uvmexp.pagesize = PAGE_SIZE;
529 }
530 uvmexp.pagemask = uvmexp.pagesize - 1;
531 if ((uvmexp.pagemask & uvmexp.pagesize) != 0)
532 panic("uvm_setpagesize: page size %u (%#x) not a power of two",
533 uvmexp.pagesize, uvmexp.pagesize);
534 for (uvmexp.pageshift = 0; ; uvmexp.pageshift++)
535 if ((1 << uvmexp.pageshift) == uvmexp.pagesize)
536 break;
537 }
538
539 /*
540 * uvm_pageboot_alloc: steal memory from physmem for bootstrapping
541 */
542
543 vaddr_t
544 uvm_pageboot_alloc(vsize_t size)
545 {
546 static bool initialized = false;
547 vaddr_t addr;
548 #if !defined(PMAP_STEAL_MEMORY)
549 vaddr_t vaddr;
550 paddr_t paddr;
551 #endif
552
553 /*
554 * on first call to this function, initialize ourselves.
555 */
556 if (initialized == false) {
557 pmap_virtual_space(&virtual_space_start, &virtual_space_end);
558
559 /* round it the way we like it */
560 virtual_space_start = round_page(virtual_space_start);
561 virtual_space_end = trunc_page(virtual_space_end);
562
563 initialized = true;
564 }
565
566 /* round to page size */
567 size = round_page(size);
568 uvmexp.bootpages += atop(size);
569
570 #if defined(PMAP_STEAL_MEMORY)
571
572 /*
573 * defer bootstrap allocation to MD code (it may want to allocate
574 * from a direct-mapped segment). pmap_steal_memory should adjust
575 * virtual_space_start/virtual_space_end if necessary.
576 */
577
578 addr = pmap_steal_memory(size, &virtual_space_start,
579 &virtual_space_end);
580
581 return(addr);
582
583 #else /* !PMAP_STEAL_MEMORY */
584
585 /*
586 * allocate virtual memory for this request
587 */
588 if (virtual_space_start == virtual_space_end ||
589 (virtual_space_end - virtual_space_start) < size)
590 panic("uvm_pageboot_alloc: out of virtual space");
591
592 addr = virtual_space_start;
593
594 #ifdef PMAP_GROWKERNEL
595 /*
596 * If the kernel pmap can't map the requested space,
597 * then allocate more resources for it.
598 */
599 if (uvm_maxkaddr < (addr + size)) {
600 uvm_maxkaddr = pmap_growkernel(addr + size);
601 if (uvm_maxkaddr < (addr + size))
602 panic("uvm_pageboot_alloc: pmap_growkernel() failed");
603 }
604 #endif
605
606 virtual_space_start += size;
607
608 /*
609 * allocate and mapin physical pages to back new virtual pages
610 */
611
612 for (vaddr = round_page(addr) ; vaddr < addr + size ;
613 vaddr += PAGE_SIZE) {
614
615 if (!uvm_page_physget(&paddr))
616 panic("uvm_pageboot_alloc: out of memory");
617
618 /*
619 * Note this memory is no longer managed, so using
620 * pmap_kenter is safe.
621 */
622 pmap_kenter_pa(vaddr, paddr, VM_PROT_READ|VM_PROT_WRITE, 0);
623 }
624 pmap_update(pmap_kernel());
625 return(addr);
626 #endif /* PMAP_STEAL_MEMORY */
627 }
628
629 #if !defined(PMAP_STEAL_MEMORY)
630 /*
631 * uvm_page_physget: "steal" one page from the vm_physmem structure.
632 *
633 * => attempt to allocate it off the end of a segment in which the "avail"
634 * values match the start/end values. if we can't do that, then we
635 * will advance both values (making them equal, and removing some
636 * vm_page structures from the non-avail area).
637 * => return false if out of memory.
638 */
639
640 /* subroutine: try to allocate from memory chunks on the specified freelist */
641 static bool uvm_page_physget_freelist(paddr_t *, int);
642
643 static bool
644 uvm_page_physget_freelist(paddr_t *paddrp, int freelist)
645 {
646 uvm_physseg_t lcv;
647
648 /* pass 1: try allocating from a matching end */
649 #if (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST)
650 for (lcv = uvm_physseg_get_last(); uvm_physseg_valid_p(lcv); lcv = uvm_physseg_get_prev(lcv))
651 #else
652 for (lcv = uvm_physseg_get_first(); uvm_physseg_valid_p(lcv); lcv = uvm_physseg_get_next(lcv))
653 #endif
654 {
655 if (uvm.page_init_done == true)
656 panic("uvm_page_physget: called _after_ bootstrap");
657
658 /* Try to match at front or back on unused segment */
659 if (uvm_page_physunload(lcv, freelist, paddrp))
660 return true;
661 }
662
663 /* pass2: forget about matching ends, just allocate something */
664 #if (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST)
665 for (lcv = uvm_physseg_get_last(); uvm_physseg_valid_p(lcv); lcv = uvm_physseg_get_prev(lcv))
666 #else
667 for (lcv = uvm_physseg_get_first(); uvm_physseg_valid_p(lcv); lcv = uvm_physseg_get_next(lcv))
668 #endif
669 {
670 /* Try the front regardless. */
671 if (uvm_page_physunload_force(lcv, freelist, paddrp))
672 return true;
673 }
674 return false;
675 }
676
677 bool
678 uvm_page_physget(paddr_t *paddrp)
679 {
680 int i;
681
682 /* try in the order of freelist preference */
683 for (i = 0; i < VM_NFREELIST; i++)
684 if (uvm_page_physget_freelist(paddrp, i) == true)
685 return (true);
686 return (false);
687 }
688 #endif /* PMAP_STEAL_MEMORY */
689
690 /*
691 * PHYS_TO_VM_PAGE: find vm_page for a PA. used by MI code to get vm_pages
692 * back from an I/O mapping (ugh!). used in some MD code as well.
693 */
694 struct vm_page *
695 uvm_phys_to_vm_page(paddr_t pa)
696 {
697 paddr_t pf = atop(pa);
698 paddr_t off;
699 uvm_physseg_t upm;
700
701 upm = uvm_physseg_find(pf, &off);
702 if (upm != UVM_PHYSSEG_TYPE_INVALID)
703 return uvm_physseg_get_pg(upm, off);
704 return(NULL);
705 }
706
707 paddr_t
708 uvm_vm_page_to_phys(const struct vm_page *pg)
709 {
710
711 return pg->phys_addr & ~(PAGE_SIZE - 1);
712 }
713
714 /*
715 * uvm_page_numa_load: load NUMA range description.
716 */
717 void
718 uvm_page_numa_load(paddr_t start, paddr_t size, u_int numa_id)
719 {
720 struct uvm_page_numa_region *d;
721
722 KASSERT(numa_id < PGFL_MAX_BUCKETS);
723
724 d = kmem_alloc(sizeof(*d), KM_SLEEP);
725 d->start = start;
726 d->size = size;
727 d->numa_id = numa_id;
728 d->next = uvm_page_numa_region;
729 uvm_page_numa_region = d;
730 }
731
732 /*
733 * uvm_page_numa_lookup: lookup NUMA node for the given page.
734 */
735 static u_int
736 uvm_page_numa_lookup(struct vm_page *pg)
737 {
738 struct uvm_page_numa_region *d;
739 static bool warned;
740 paddr_t pa;
741
742 KASSERT(uvm.numa_alloc);
743 KASSERT(uvm_page_numa_region != NULL);
744
745 pa = VM_PAGE_TO_PHYS(pg);
746 for (d = uvm_page_numa_region; d != NULL; d = d->next) {
747 if (pa >= d->start && pa < d->start + d->size) {
748 return d->numa_id;
749 }
750 }
751
752 if (!warned) {
753 printf("uvm_page_numa_lookup: failed, first pg=%p pa=%#"
754 PRIxPADDR "\n", pg, VM_PAGE_TO_PHYS(pg));
755 warned = true;
756 }
757
758 return 0;
759 }
760
761 /*
762 * uvm_page_redim: adjust freelist dimensions if they have changed.
763 */
764
765 static void
766 uvm_page_redim(int newncolors, int newnbuckets)
767 {
768 struct pgfreelist npgfl;
769 struct pgflbucket *opgb, *npgb;
770 struct pgflist *ohead, *nhead;
771 struct vm_page *pg;
772 size_t bucketsize, bucketmemsize, oldbucketmemsize;
773 int fl, ob, oc, nb, nc, obuckets, ocolors;
774 char *bucketarray, *oldbucketmem, *bucketmem;
775
776 KASSERT(((newncolors - 1) & newncolors) == 0);
777
778 /* Anything to do? */
779 if (newncolors <= uvmexp.ncolors &&
780 newnbuckets == uvm.bucketcount) {
781 return;
782 }
783 if (uvm.page_init_done == false) {
784 uvmexp.ncolors = newncolors;
785 return;
786 }
787
788 bucketsize = offsetof(struct pgflbucket, pgb_colors[newncolors]);
789 bucketsize = roundup2(bucketsize, coherency_unit);
790 bucketmemsize = bucketsize * newnbuckets * VM_NFREELIST +
791 coherency_unit - 1;
792 bucketmem = kmem_zalloc(bucketmemsize, KM_SLEEP);
793 bucketarray = (char *)roundup2((uintptr_t)bucketmem, coherency_unit);
794
795 ocolors = uvmexp.ncolors;
796 obuckets = uvm.bucketcount;
797
798 /* Freelist cache musn't be enabled. */
799 uvm_pgflcache_pause();
800
801 /* Make sure we should still do this. */
802 uvm_pgfl_lock();
803 if (newncolors <= uvmexp.ncolors &&
804 newnbuckets == uvm.bucketcount) {
805 uvm_pgfl_unlock();
806 uvm_pgflcache_resume();
807 kmem_free(bucketmem, bucketmemsize);
808 return;
809 }
810
811 uvmexp.ncolors = newncolors;
812 uvmexp.colormask = uvmexp.ncolors - 1;
813 uvm.bucketcount = newnbuckets;
814
815 for (fl = 0; fl < VM_NFREELIST; fl++) {
816 /* Init new buckets in new freelist. */
817 memset(&npgfl, 0, sizeof(npgfl));
818 for (nb = 0; nb < newnbuckets; nb++) {
819 npgb = (struct pgflbucket *)bucketarray;
820 uvm_page_init_bucket(&npgfl, npgb, nb);
821 bucketarray += bucketsize;
822 }
823 /* Now transfer pages from the old freelist. */
824 for (nb = ob = 0; ob < obuckets; ob++) {
825 opgb = uvm.page_free[fl].pgfl_buckets[ob];
826 for (oc = 0; oc < ocolors; oc++) {
827 ohead = &opgb->pgb_colors[oc];
828 while ((pg = LIST_FIRST(ohead)) != NULL) {
829 LIST_REMOVE(pg, pageq.list);
830 /*
831 * Here we decide on the NEW color &
832 * bucket for the page. For NUMA
833 * we'll use the info that the
834 * hardware gave us. For non-NUMA
835 * assign take physical page frame
836 * number and cache color into
837 * account. We do this to try and
838 * avoid defeating any memory
839 * interleaving in the hardware.
840 */
841 KASSERT(
842 uvm_page_get_bucket(pg) == ob);
843 KASSERT(fl ==
844 uvm_page_get_freelist(pg));
845 if (uvm.numa_alloc) {
846 nb = uvm_page_numa_lookup(pg);
847 } else {
848 nb = atop(VM_PAGE_TO_PHYS(pg))
849 / uvmexp.ncolors / 8
850 % newnbuckets;
851 }
852 uvm_page_set_bucket(pg, nb);
853 npgb = npgfl.pgfl_buckets[nb];
854 npgb->pgb_nfree++;
855 nc = VM_PGCOLOR(pg);
856 nhead = &npgb->pgb_colors[nc];
857 LIST_INSERT_HEAD(nhead, pg, pageq.list);
858 }
859 }
860 }
861 /* Install the new freelist. */
862 memcpy(&uvm.page_free[fl], &npgfl, sizeof(npgfl));
863 }
864
865 /* Unlock and free the old memory. */
866 oldbucketmemsize = recolored_pages_memsize;
867 oldbucketmem = recolored_pages_mem;
868 recolored_pages_memsize = bucketmemsize;
869 recolored_pages_mem = bucketmem;
870
871 uvm_pgfl_unlock();
872 uvm_pgflcache_resume();
873
874 if (oldbucketmemsize) {
875 kmem_free(oldbucketmem, oldbucketmemsize);
876 }
877
878 /*
879 * this calls uvm_km_alloc() which may want to hold
880 * uvm_freelist_lock.
881 */
882 uvm_pager_realloc_emerg();
883 }
884
885 /*
886 * uvm_page_recolor: Recolor the pages if the new color count is
887 * larger than the old one.
888 */
889
890 void
891 uvm_page_recolor(int newncolors)
892 {
893
894 uvm_page_redim(newncolors, uvm.bucketcount);
895 }
896
897 /*
898 * uvm_page_rebucket: Determine a bucket structure and redim the free
899 * lists to match.
900 */
901
902 void
903 uvm_page_rebucket(void)
904 {
905 u_int min_numa, max_numa, npackage, shift;
906 struct cpu_info *ci, *ci2, *ci3;
907 CPU_INFO_ITERATOR cii;
908
909 /*
910 * If we have more than one NUMA node, and the maximum NUMA node ID
911 * is less than PGFL_MAX_BUCKETS, then we'll use NUMA distribution
912 * for free pages. uvm_pagefree() will not reassign pages to a
913 * different bucket on free.
914 */
915 min_numa = (u_int)-1;
916 max_numa = 0;
917 for (CPU_INFO_FOREACH(cii, ci)) {
918 if (ci->ci_numa_id < min_numa) {
919 min_numa = ci->ci_numa_id;
920 }
921 if (ci->ci_numa_id > max_numa) {
922 max_numa = ci->ci_numa_id;
923 }
924 }
925 if (min_numa != max_numa && max_numa < PGFL_MAX_BUCKETS) {
926 #ifdef NUMA
927 /*
928 * We can do this, and it seems to work well, but until
929 * further experiments are done we'll stick with the cache
930 * locality strategy.
931 */
932 aprint_debug("UVM: using NUMA allocation scheme\n");
933 for (CPU_INFO_FOREACH(cii, ci)) {
934 ci->ci_data.cpu_uvm->pgflbucket = ci->ci_numa_id;
935 }
936 uvm.numa_alloc = true;
937 uvm_page_redim(uvmexp.ncolors, max_numa + 1);
938 return;
939 #endif
940 }
941
942 /*
943 * Otherwise we'll go with a scheme to maximise L2/L3 cache locality
944 * and minimise lock contention. Count the total number of CPU
945 * packages, and then try to distribute the buckets among CPU
946 * packages evenly. uvm_pagefree() will reassign pages to the
947 * freeing CPU's preferred bucket on free.
948 */
949 npackage = curcpu()->ci_nsibling[CPUREL_PACKAGE1ST];
950
951 /*
952 * Figure out how to arrange the packages & buckets, and the total
953 * number of buckets we need. XXX 2 may not be the best factor.
954 */
955 for (shift = 0; npackage > PGFL_MAX_BUCKETS; shift++) {
956 npackage >>= 1;
957 }
958 uvm_page_redim(uvmexp.ncolors, npackage);
959
960 /*
961 * Now tell each CPU which bucket to use. In the outer loop, scroll
962 * through all CPU packages.
963 */
964 npackage = 0;
965 ci = curcpu();
966 ci2 = ci->ci_sibling[CPUREL_PACKAGE1ST];
967 do {
968 /*
969 * In the inner loop, scroll through all CPUs in the package
970 * and assign the same bucket ID.
971 */
972 ci3 = ci2;
973 do {
974 ci3->ci_data.cpu_uvm->pgflbucket = npackage >> shift;
975 ci3 = ci3->ci_sibling[CPUREL_PACKAGE];
976 } while (ci3 != ci2);
977 npackage++;
978 ci2 = ci2->ci_sibling[CPUREL_PACKAGE1ST];
979 } while (ci2 != ci->ci_sibling[CPUREL_PACKAGE1ST]);
980
981 aprint_debug("UVM: using package allocation scheme, "
982 "%d package(s) per bucket\n", 1 << shift);
983 }
984
985 /*
986 * uvm_cpu_attach: initialize per-CPU data structures.
987 */
988
989 void
990 uvm_cpu_attach(struct cpu_info *ci)
991 {
992 struct uvm_cpu *ucpu;
993
994 /* Already done in uvm_page_init(). */
995 if (!CPU_IS_PRIMARY(ci)) {
996 /* Add more reserve pages for this CPU. */
997 uvmexp.reserve_kernel += vm_page_reserve_kernel;
998
999 /* Allocate per-CPU data structures. */
1000 ucpu = kmem_zalloc(sizeof(struct uvm_cpu) + coherency_unit - 1,
1001 KM_SLEEP);
1002 ucpu = (struct uvm_cpu *)roundup2((uintptr_t)ucpu,
1003 coherency_unit);
1004 ci->ci_data.cpu_uvm = ucpu;
1005 } else {
1006 ucpu = ci->ci_data.cpu_uvm;
1007 }
1008
1009 uvmpdpol_init_cpu(ucpu);
1010
1011 /*
1012 * Attach RNG source for this CPU's VM events
1013 */
1014 rnd_attach_source(&ucpu->rs, ci->ci_data.cpu_name, RND_TYPE_VM,
1015 RND_FLAG_COLLECT_TIME|RND_FLAG_COLLECT_VALUE|
1016 RND_FLAG_ESTIMATE_VALUE);
1017 }
1018
1019 /*
1020 * uvm_availmem: fetch the total amount of free memory in pages. this can
1021 * have a detrimental effect on performance due to false sharing; don't call
1022 * unless needed.
1023 */
1024
1025 int
1026 uvm_availmem(void)
1027 {
1028 struct pgfreelist *pgfl;
1029 int fl, b, fpages;
1030
1031 fpages = 0;
1032 for (fl = 0; fl < VM_NFREELIST; fl++) {
1033 pgfl = &uvm.page_free[fl];
1034 for (b = 0; b < uvm.bucketcount; b++) {
1035 fpages += pgfl->pgfl_buckets[b]->pgb_nfree;
1036 }
1037 }
1038 return fpages;
1039 }
1040
1041 /*
1042 * uvm_pagealloc_pgb: helper routine that tries to allocate any color from a
1043 * specific freelist and specific bucket only.
1044 *
1045 * => must be at IPL_VM or higher to protect per-CPU data structures.
1046 */
1047
1048 static struct vm_page *
1049 uvm_pagealloc_pgb(struct uvm_cpu *ucpu, int f, int b, int *trycolorp, int flags)
1050 {
1051 int c, trycolor, colormask;
1052 struct pgflbucket *pgb;
1053 struct vm_page *pg;
1054 kmutex_t *lock;
1055 bool fill;
1056
1057 /*
1058 * Skip the bucket if empty, no lock needed. There could be many
1059 * empty freelists/buckets.
1060 */
1061 pgb = uvm.page_free[f].pgfl_buckets[b];
1062 if (pgb->pgb_nfree == 0) {
1063 return NULL;
1064 }
1065
1066 /* Skip bucket if low on memory. */
1067 lock = &uvm_freelist_locks[b].lock;
1068 mutex_spin_enter(lock);
1069 if (__predict_false(pgb->pgb_nfree <= uvmexp.reserve_kernel)) {
1070 if ((flags & UVM_PGA_USERESERVE) == 0 ||
1071 (pgb->pgb_nfree <= uvmexp.reserve_pagedaemon &&
1072 curlwp != uvm.pagedaemon_lwp)) {
1073 mutex_spin_exit(lock);
1074 return NULL;
1075 }
1076 fill = false;
1077 } else {
1078 fill = true;
1079 }
1080
1081 /* Try all page colors as needed. */
1082 c = trycolor = *trycolorp;
1083 colormask = uvmexp.colormask;
1084 do {
1085 pg = LIST_FIRST(&pgb->pgb_colors[c]);
1086 if (__predict_true(pg != NULL)) {
1087 /*
1088 * Got a free page! PG_FREE must be cleared under
1089 * lock because of uvm_pglistalloc().
1090 */
1091 LIST_REMOVE(pg, pageq.list);
1092 KASSERT(pg->flags & PG_FREE);
1093 pg->flags &= PG_ZERO;
1094 pgb->pgb_nfree--;
1095
1096 /*
1097 * While we have the bucket locked and our data
1098 * structures fresh in L1 cache, we have an ideal
1099 * opportunity to grab some pages for the freelist
1100 * cache without causing extra contention. Only do
1101 * so if we found pages in this CPU's preferred
1102 * bucket.
1103 */
1104 if (__predict_true(b == ucpu->pgflbucket && fill)) {
1105 uvm_pgflcache_fill(ucpu, f, b, c);
1106 }
1107 mutex_spin_exit(lock);
1108 KASSERT(uvm_page_get_bucket(pg) == b);
1109 CPU_COUNT(c == trycolor ?
1110 CPU_COUNT_COLORHIT : CPU_COUNT_COLORMISS, 1);
1111 CPU_COUNT(CPU_COUNT_CPUMISS, 1);
1112 *trycolorp = c;
1113 return pg;
1114 }
1115 c = (c + 1) & colormask;
1116 } while (c != trycolor);
1117 mutex_spin_exit(lock);
1118
1119 return NULL;
1120 }
1121
1122 /*
1123 * uvm_pagealloc_pgfl: helper routine for uvm_pagealloc_strat that allocates
1124 * any color from any bucket, in a specific freelist.
1125 *
1126 * => must be at IPL_VM or higher to protect per-CPU data structures.
1127 */
1128
1129 static struct vm_page *
1130 uvm_pagealloc_pgfl(struct uvm_cpu *ucpu, int f, int *trycolorp, int flags)
1131 {
1132 int b, trybucket, bucketcount;
1133 struct vm_page *pg;
1134
1135 /* Try for the exact thing in the per-CPU cache. */
1136 if ((pg = uvm_pgflcache_alloc(ucpu, f, *trycolorp)) != NULL) {
1137 CPU_COUNT(CPU_COUNT_CPUHIT, 1);
1138 CPU_COUNT(CPU_COUNT_COLORHIT, 1);
1139 return pg;
1140 }
1141
1142 /* Walk through all buckets, trying our preferred bucket first. */
1143 trybucket = ucpu->pgflbucket;
1144 b = trybucket;
1145 bucketcount = uvm.bucketcount;
1146 do {
1147 pg = uvm_pagealloc_pgb(ucpu, f, b, trycolorp, flags);
1148 if (pg != NULL) {
1149 return pg;
1150 }
1151 b = (b + 1 == bucketcount ? 0 : b + 1);
1152 } while (b != trybucket);
1153
1154 return NULL;
1155 }
1156
1157 /*
1158 * uvm_pagealloc_strat: allocate vm_page from a particular free list.
1159 *
1160 * => return null if no pages free
1161 * => wake up pagedaemon if number of free pages drops below low water mark
1162 * => if obj != NULL, obj must be locked (to put in obj's tree)
1163 * => if anon != NULL, anon must be locked (to put in anon)
1164 * => only one of obj or anon can be non-null
1165 * => caller must activate/deactivate page if it is not wired.
1166 * => free_list is ignored if strat == UVM_PGA_STRAT_NORMAL.
1167 * => policy decision: it is more important to pull a page off of the
1168 * appropriate priority free list than it is to get a zero'd or
1169 * unknown contents page. This is because we live with the
1170 * consequences of a bad free list decision for the entire
1171 * lifetime of the page, e.g. if the page comes from memory that
1172 * is slower to access.
1173 */
1174
1175 struct vm_page *
1176 uvm_pagealloc_strat(struct uvm_object *obj, voff_t off, struct vm_anon *anon,
1177 int flags, int strat, int free_list)
1178 {
1179 int zeroit = 0, color;
1180 int lcv, error, s;
1181 struct uvm_cpu *ucpu;
1182 struct vm_page *pg;
1183 lwp_t *l;
1184
1185 KASSERT(obj == NULL || anon == NULL);
1186 KASSERT(anon == NULL || (flags & UVM_FLAG_COLORMATCH) || off == 0);
1187 KASSERT(off == trunc_page(off));
1188 KASSERT(obj == NULL || rw_write_held(obj->vmobjlock));
1189 KASSERT(anon == NULL || anon->an_lock == NULL ||
1190 rw_write_held(anon->an_lock));
1191
1192 /*
1193 * This implements a global round-robin page coloring
1194 * algorithm.
1195 */
1196
1197 s = splvm();
1198 ucpu = curcpu()->ci_data.cpu_uvm;
1199 if (flags & UVM_FLAG_COLORMATCH) {
1200 color = atop(off) & uvmexp.colormask;
1201 } else {
1202 color = ucpu->pgflcolor;
1203 }
1204
1205 /*
1206 * fail if any of these conditions is true:
1207 * [1] there really are no free pages, or
1208 * [2] only kernel "reserved" pages remain and
1209 * reserved pages have not been requested.
1210 * [3] only pagedaemon "reserved" pages remain and
1211 * the requestor isn't the pagedaemon.
1212 * we make kernel reserve pages available if called by a
1213 * kernel thread or a realtime thread.
1214 */
1215 l = curlwp;
1216 if (__predict_true(l != NULL) && lwp_eprio(l) >= PRI_KTHREAD) {
1217 flags |= UVM_PGA_USERESERVE;
1218 }
1219
1220 /* If the allocator's running in NUMA mode, go with NUMA strategy. */
1221 if (uvm.numa_alloc && strat == UVM_PGA_STRAT_NORMAL) {
1222 strat = UVM_PGA_STRAT_NUMA;
1223 }
1224
1225 again:
1226 switch (strat) {
1227 case UVM_PGA_STRAT_NORMAL:
1228 /* Check freelists: descending priority (ascending id) order. */
1229 for (lcv = 0; lcv < VM_NFREELIST; lcv++) {
1230 pg = uvm_pagealloc_pgfl(ucpu, lcv, &color, flags);
1231 if (pg != NULL) {
1232 goto gotit;
1233 }
1234 }
1235
1236 /* No pages free! Have pagedaemon free some memory. */
1237 splx(s);
1238 uvm_kick_pdaemon();
1239 return NULL;
1240
1241 case UVM_PGA_STRAT_ONLY:
1242 case UVM_PGA_STRAT_FALLBACK:
1243 /* Attempt to allocate from the specified free list. */
1244 KASSERT(free_list >= 0 && free_list < VM_NFREELIST);
1245 pg = uvm_pagealloc_pgfl(ucpu, free_list, &color, flags);
1246 if (pg != NULL) {
1247 goto gotit;
1248 }
1249
1250 /* Fall back, if possible. */
1251 if (strat == UVM_PGA_STRAT_FALLBACK) {
1252 strat = UVM_PGA_STRAT_NORMAL;
1253 goto again;
1254 }
1255
1256 /* No pages free! Have pagedaemon free some memory. */
1257 splx(s);
1258 uvm_kick_pdaemon();
1259 return NULL;
1260
1261 case UVM_PGA_STRAT_NUMA:
1262 /*
1263 * NUMA strategy: allocating from the correct bucket is more
1264 * important than observing freelist priority. Look only to
1265 * the current NUMA node; if that fails, we need to look to
1266 * other NUMA nodes, so retry with the normal strategy.
1267 */
1268 for (lcv = 0; lcv < VM_NFREELIST; lcv++) {
1269 pg = uvm_pgflcache_alloc(ucpu, lcv, color);
1270 if (pg != NULL) {
1271 CPU_COUNT(CPU_COUNT_CPUHIT, 1);
1272 CPU_COUNT(CPU_COUNT_COLORHIT, 1);
1273 goto gotit;
1274 }
1275 pg = uvm_pagealloc_pgb(ucpu, lcv,
1276 ucpu->pgflbucket, &color, flags);
1277 if (pg != NULL) {
1278 goto gotit;
1279 }
1280 }
1281 strat = UVM_PGA_STRAT_NORMAL;
1282 goto again;
1283
1284 default:
1285 panic("uvm_pagealloc_strat: bad strat %d", strat);
1286 /* NOTREACHED */
1287 }
1288
1289 gotit:
1290 /*
1291 * We now know which color we actually allocated from; set
1292 * the next color accordingly.
1293 */
1294
1295 ucpu->pgflcolor = (color + 1) & uvmexp.colormask;
1296
1297 /*
1298 * while still at IPL_VM, update allocation statistics and remember
1299 * if we have to zero the page
1300 */
1301
1302 if (flags & UVM_PGA_ZERO) {
1303 if (pg->flags & PG_ZERO) {
1304 CPU_COUNT(CPU_COUNT_PGA_ZEROHIT, 1);
1305 zeroit = 0;
1306 } else {
1307 CPU_COUNT(CPU_COUNT_PGA_ZEROMISS, 1);
1308 zeroit = 1;
1309 }
1310 }
1311 if (pg->flags & PG_ZERO) {
1312 CPU_COUNT(CPU_COUNT_ZEROPAGES, -1);
1313 }
1314 if (anon) {
1315 CPU_COUNT(CPU_COUNT_ANONPAGES, 1);
1316 CPU_COUNT(CPU_COUNT_ANONCLEAN, 1);
1317 }
1318 splx(s);
1319 KASSERT((pg->flags & ~(PG_ZERO|PG_FREE)) == 0);
1320
1321 /*
1322 * assign the page to the object. as the page was free, we know
1323 * that pg->uobject and pg->uanon are NULL. we only need to take
1324 * the page's interlock if we are changing the values.
1325 */
1326 if (anon != NULL || obj != NULL) {
1327 mutex_enter(&pg->interlock);
1328 }
1329 pg->offset = off;
1330 pg->uobject = obj;
1331 pg->uanon = anon;
1332 KASSERT(uvm_page_owner_locked_p(pg, true));
1333 pg->flags = PG_BUSY|PG_CLEAN|PG_FAKE;
1334 if (anon) {
1335 anon->an_page = pg;
1336 pg->flags |= PG_ANON;
1337 mutex_exit(&pg->interlock);
1338 } else if (obj) {
1339 /*
1340 * set PG_FILE|PG_AOBJ before the first uvm_pageinsert.
1341 */
1342 if (UVM_OBJ_IS_VNODE(obj)) {
1343 pg->flags |= PG_FILE;
1344 } else {
1345 pg->flags |= PG_AOBJ;
1346 }
1347 uvm_pageinsert_object(obj, pg);
1348 mutex_exit(&pg->interlock);
1349 error = uvm_pageinsert_tree(obj, pg);
1350 if (error != 0) {
1351 mutex_enter(&pg->interlock);
1352 uvm_pageremove_object(obj, pg);
1353 mutex_exit(&pg->interlock);
1354 uvm_pagefree(pg);
1355 return NULL;
1356 }
1357 }
1358
1359 #if defined(UVM_PAGE_TRKOWN)
1360 pg->owner_tag = NULL;
1361 #endif
1362 UVM_PAGE_OWN(pg, "new alloc");
1363
1364 if (flags & UVM_PGA_ZERO) {
1365 /*
1366 * A zero'd page is not clean. If we got a page not already
1367 * zero'd, then we have to zero it ourselves.
1368 */
1369 if (obj != NULL || anon != NULL) {
1370 uvm_pagemarkdirty(pg, UVM_PAGE_STATUS_DIRTY);
1371 }
1372 if (zeroit) {
1373 pmap_zero_page(VM_PAGE_TO_PHYS(pg));
1374 }
1375 }
1376
1377 return(pg);
1378 }
1379
1380 /*
1381 * uvm_pagereplace: replace a page with another
1382 *
1383 * => object must be locked
1384 * => page interlocks must be held
1385 */
1386
1387 void
1388 uvm_pagereplace(struct vm_page *oldpg, struct vm_page *newpg)
1389 {
1390 struct uvm_object *uobj = oldpg->uobject;
1391 struct vm_page *pg __diagused;
1392 uint64_t idx;
1393
1394 KASSERT((oldpg->flags & PG_TABLED) != 0);
1395 KASSERT(uobj != NULL);
1396 KASSERT((newpg->flags & PG_TABLED) == 0);
1397 KASSERT(newpg->uobject == NULL);
1398 KASSERT(rw_write_held(uobj->vmobjlock));
1399 KASSERT(mutex_owned(&oldpg->interlock));
1400 KASSERT(mutex_owned(&newpg->interlock));
1401
1402 newpg->uobject = uobj;
1403 newpg->offset = oldpg->offset;
1404 idx = newpg->offset >> PAGE_SHIFT;
1405 pg = radix_tree_replace_node(&uobj->uo_pages, idx, newpg);
1406 KASSERT(pg == oldpg);
1407 if (((oldpg->flags ^ newpg->flags) & PG_CLEAN) != 0) {
1408 if ((newpg->flags & PG_CLEAN) != 0) {
1409 radix_tree_clear_tag(&uobj->uo_pages, idx,
1410 UVM_PAGE_DIRTY_TAG);
1411 } else {
1412 radix_tree_set_tag(&uobj->uo_pages, idx,
1413 UVM_PAGE_DIRTY_TAG);
1414 }
1415 }
1416 /*
1417 * oldpg's PG_STAT is stable. newpg is not reachable by others yet.
1418 */
1419 newpg->flags |=
1420 (newpg->flags & ~PG_STAT) | (oldpg->flags & PG_STAT);
1421 uvm_pageinsert_object(uobj, newpg);
1422 uvm_pageremove_object(uobj, oldpg);
1423 }
1424
1425 /*
1426 * uvm_pagerealloc: reallocate a page from one object to another
1427 *
1428 * => both objects must be locked
1429 * => both interlocks must be held
1430 */
1431
1432 void
1433 uvm_pagerealloc(struct vm_page *pg, struct uvm_object *newobj, voff_t newoff)
1434 {
1435 /*
1436 * remove it from the old object
1437 */
1438
1439 if (pg->uobject) {
1440 uvm_pageremove_tree(pg->uobject, pg);
1441 uvm_pageremove_object(pg->uobject, pg);
1442 }
1443
1444 /*
1445 * put it in the new object
1446 */
1447
1448 if (newobj) {
1449 /*
1450 * XXX we have no in-tree users of this functionality
1451 */
1452 panic("uvm_pagerealloc: no impl");
1453 }
1454 }
1455
1456 #ifdef DEBUG
1457 /*
1458 * check if page is zero-filled
1459 */
1460 void
1461 uvm_pagezerocheck(struct vm_page *pg)
1462 {
1463 int *p, *ep;
1464
1465 KASSERT(uvm_zerocheckkva != 0);
1466
1467 /*
1468 * XXX assuming pmap_kenter_pa and pmap_kremove never call
1469 * uvm page allocator.
1470 *
1471 * it might be better to have "CPU-local temporary map" pmap interface.
1472 */
1473 mutex_spin_enter(&uvm_zerochecklock);
1474 pmap_kenter_pa(uvm_zerocheckkva, VM_PAGE_TO_PHYS(pg), VM_PROT_READ, 0);
1475 p = (int *)uvm_zerocheckkva;
1476 ep = (int *)((char *)p + PAGE_SIZE);
1477 pmap_update(pmap_kernel());
1478 while (p < ep) {
1479 if (*p != 0)
1480 panic("PG_ZERO page isn't zero-filled");
1481 p++;
1482 }
1483 pmap_kremove(uvm_zerocheckkva, PAGE_SIZE);
1484 mutex_spin_exit(&uvm_zerochecklock);
1485 /*
1486 * pmap_update() is not necessary here because no one except us
1487 * uses this VA.
1488 */
1489 }
1490 #endif /* DEBUG */
1491
1492 /*
1493 * uvm_pagefree: free page
1494 *
1495 * => erase page's identity (i.e. remove from object)
1496 * => put page on free list
1497 * => caller must lock owning object (either anon or uvm_object)
1498 * => assumes all valid mappings of pg are gone
1499 */
1500
1501 void
1502 uvm_pagefree(struct vm_page *pg)
1503 {
1504 struct pgfreelist *pgfl;
1505 struct pgflbucket *pgb;
1506 struct uvm_cpu *ucpu;
1507 kmutex_t *lock;
1508 int bucket, s;
1509 bool locked;
1510
1511 #ifdef DEBUG
1512 if (pg->uobject == (void *)0xdeadbeef &&
1513 pg->uanon == (void *)0xdeadbeef) {
1514 panic("uvm_pagefree: freeing free page %p", pg);
1515 }
1516 #endif /* DEBUG */
1517
1518 KASSERT((pg->flags & PG_PAGEOUT) == 0);
1519 KASSERT(!(pg->flags & PG_FREE));
1520 KASSERT(pg->uobject == NULL || rw_write_held(pg->uobject->vmobjlock));
1521 KASSERT(pg->uobject != NULL || pg->uanon == NULL ||
1522 rw_write_held(pg->uanon->an_lock));
1523
1524 /*
1525 * remove the page from the object's tree beore acquiring any page
1526 * interlocks: this can acquire locks to free radixtree nodes.
1527 */
1528 if (pg->uobject != NULL) {
1529 uvm_pageremove_tree(pg->uobject, pg);
1530 }
1531
1532 /*
1533 * if the page is loaned, resolve the loan instead of freeing.
1534 */
1535
1536 if (pg->loan_count) {
1537 KASSERT(pg->wire_count == 0);
1538
1539 /*
1540 * if the page is owned by an anon then we just want to
1541 * drop anon ownership. the kernel will free the page when
1542 * it is done with it. if the page is owned by an object,
1543 * remove it from the object and mark it dirty for the benefit
1544 * of possible anon owners.
1545 *
1546 * regardless of previous ownership, wakeup any waiters,
1547 * unbusy the page, and we're done.
1548 */
1549
1550 uvm_pagelock(pg);
1551 locked = true;
1552 if (pg->uobject != NULL) {
1553 uvm_pageremove_object(pg->uobject, pg);
1554 pg->flags &= ~(PG_FILE|PG_AOBJ);
1555 } else if (pg->uanon != NULL) {
1556 if ((pg->flags & PG_ANON) == 0) {
1557 pg->loan_count--;
1558 } else {
1559 pg->flags &= ~PG_ANON;
1560 cpu_count(CPU_COUNT_ANONPAGES, -1);
1561 }
1562 pg->uanon->an_page = NULL;
1563 pg->uanon = NULL;
1564 }
1565 if (pg->flags & PG_WANTED) {
1566 wakeup(pg);
1567 }
1568 pg->flags &= ~(PG_WANTED|PG_BUSY|PG_RELEASED|PG_PAGER1);
1569 #ifdef UVM_PAGE_TRKOWN
1570 pg->owner_tag = NULL;
1571 #endif
1572 KASSERT((pg->flags & PG_STAT) == 0);
1573 if (pg->loan_count) {
1574 KASSERT(pg->uobject == NULL);
1575 if (pg->uanon == NULL) {
1576 uvm_pagedequeue(pg);
1577 }
1578 uvm_pageunlock(pg);
1579 return;
1580 }
1581 } else if (pg->uobject != NULL || pg->uanon != NULL ||
1582 pg->wire_count != 0) {
1583 uvm_pagelock(pg);
1584 locked = true;
1585 } else {
1586 locked = false;
1587 }
1588
1589 /*
1590 * remove page from its object or anon.
1591 */
1592 if (pg->uobject != NULL) {
1593 uvm_pageremove_object(pg->uobject, pg);
1594 } else if (pg->uanon != NULL) {
1595 const unsigned int status = uvm_pagegetdirty(pg);
1596 pg->uanon->an_page = NULL;
1597 pg->uanon = NULL;
1598 kpreempt_disable();
1599 CPU_COUNT(CPU_COUNT_ANONPAGES, -1);
1600 CPU_COUNT(CPU_COUNT_ANONUNKNOWN + status, -1);
1601 kpreempt_enable();
1602 }
1603
1604 /*
1605 * if the page was wired, unwire it now.
1606 */
1607
1608 if (pg->wire_count) {
1609 pg->wire_count = 0;
1610 atomic_dec_uint(&uvmexp.wired);
1611 }
1612 if (locked) {
1613 /*
1614 * now remove the page from the queues.
1615 */
1616 uvm_pagedequeue(pg);
1617 uvm_pageunlock(pg);
1618 } else {
1619 KASSERT(!uvmpdpol_pageisqueued_p(pg));
1620 }
1621
1622 /*
1623 * and put on free queue
1624 */
1625
1626 #ifdef DEBUG
1627 pg->uobject = (void *)0xdeadbeef;
1628 pg->uanon = (void *)0xdeadbeef;
1629 if (pg->flags & PG_ZERO)
1630 uvm_pagezerocheck(pg);
1631 #endif /* DEBUG */
1632
1633 /* Try to send the page to the per-CPU cache. */
1634 s = splvm();
1635 if (pg->flags & PG_ZERO) {
1636 CPU_COUNT(CPU_COUNT_ZEROPAGES, 1);
1637 }
1638 ucpu = curcpu()->ci_data.cpu_uvm;
1639 bucket = uvm_page_get_bucket(pg);
1640 if (bucket == ucpu->pgflbucket && uvm_pgflcache_free(ucpu, pg)) {
1641 splx(s);
1642 return;
1643 }
1644
1645 /* Didn't work. Never mind, send it to a global bucket. */
1646 pgfl = &uvm.page_free[uvm_page_get_freelist(pg)];
1647 pgb = pgfl->pgfl_buckets[bucket];
1648 lock = &uvm_freelist_locks[bucket].lock;
1649
1650 mutex_spin_enter(lock);
1651 /* PG_FREE must be set under lock because of uvm_pglistalloc(). */
1652 pg->flags = (pg->flags & PG_ZERO) | PG_FREE;
1653 LIST_INSERT_HEAD(&pgb->pgb_colors[VM_PGCOLOR(pg)], pg, pageq.list);
1654 pgb->pgb_nfree++;
1655 mutex_spin_exit(lock);
1656 splx(s);
1657 }
1658
1659 /*
1660 * uvm_page_unbusy: unbusy an array of pages.
1661 *
1662 * => pages must either all belong to the same object, or all belong to anons.
1663 * => if pages are object-owned, object must be locked.
1664 * => if pages are anon-owned, anons must be locked.
1665 * => caller must make sure that anon-owned pages are not PG_RELEASED.
1666 */
1667
1668 void
1669 uvm_page_unbusy(struct vm_page **pgs, int npgs)
1670 {
1671 struct vm_page *pg;
1672 int i;
1673 UVMHIST_FUNC("uvm_page_unbusy"); UVMHIST_CALLED(ubchist);
1674
1675 for (i = 0; i < npgs; i++) {
1676 pg = pgs[i];
1677 if (pg == NULL || pg == PGO_DONTCARE) {
1678 continue;
1679 }
1680
1681 KASSERT(uvm_page_owner_locked_p(pg, true));
1682 KASSERT(pg->flags & PG_BUSY);
1683 KASSERT((pg->flags & PG_PAGEOUT) == 0);
1684 if (pg->flags & PG_WANTED) {
1685 /* XXXAD thundering herd problem. */
1686 wakeup(pg);
1687 }
1688 if (pg->flags & PG_RELEASED) {
1689 UVMHIST_LOG(ubchist, "releasing pg %#jx",
1690 (uintptr_t)pg, 0, 0, 0);
1691 KASSERT(pg->uobject != NULL ||
1692 (pg->uanon != NULL && pg->uanon->an_ref > 0));
1693 pg->flags &= ~PG_RELEASED;
1694 uvm_pagefree(pg);
1695 } else {
1696 UVMHIST_LOG(ubchist, "unbusying pg %#jx",
1697 (uintptr_t)pg, 0, 0, 0);
1698 KASSERT((pg->flags & PG_FAKE) == 0);
1699 pg->flags &= ~(PG_WANTED|PG_BUSY);
1700 UVM_PAGE_OWN(pg, NULL);
1701 }
1702 }
1703 }
1704
1705 #if defined(UVM_PAGE_TRKOWN)
1706 /*
1707 * uvm_page_own: set or release page ownership
1708 *
1709 * => this is a debugging function that keeps track of who sets PG_BUSY
1710 * and where they do it. it can be used to track down problems
1711 * such a process setting "PG_BUSY" and never releasing it.
1712 * => page's object [if any] must be locked
1713 * => if "tag" is NULL then we are releasing page ownership
1714 */
1715 void
1716 uvm_page_own(struct vm_page *pg, const char *tag)
1717 {
1718
1719 KASSERT((pg->flags & (PG_PAGEOUT|PG_RELEASED)) == 0);
1720 KASSERT((pg->flags & PG_WANTED) == 0);
1721 KASSERT(uvm_page_owner_locked_p(pg, true));
1722
1723 /* gain ownership? */
1724 if (tag) {
1725 KASSERT((pg->flags & PG_BUSY) != 0);
1726 if (pg->owner_tag) {
1727 printf("uvm_page_own: page %p already owned "
1728 "by proc %d [%s]\n", pg,
1729 pg->owner, pg->owner_tag);
1730 panic("uvm_page_own");
1731 }
1732 pg->owner = curproc->p_pid;
1733 pg->lowner = curlwp->l_lid;
1734 pg->owner_tag = tag;
1735 return;
1736 }
1737
1738 /* drop ownership */
1739 KASSERT((pg->flags & PG_BUSY) == 0);
1740 if (pg->owner_tag == NULL) {
1741 printf("uvm_page_own: dropping ownership of an non-owned "
1742 "page (%p)\n", pg);
1743 panic("uvm_page_own");
1744 }
1745 pg->owner_tag = NULL;
1746 }
1747 #endif
1748
1749 /*
1750 * uvm_pageidlezero: zero free pages while the system is idle.
1751 */
1752 void
1753 uvm_pageidlezero(void)
1754 {
1755
1756 /*
1757 * Disabled for the moment. Previous strategy too cache heavy. In
1758 * the future we may experiment with zeroing the pages held in the
1759 * per-CPU cache (uvm_pgflcache).
1760 */
1761 }
1762
1763 /*
1764 * uvm_pagelookup: look up a page
1765 *
1766 * => caller should lock object to keep someone from pulling the page
1767 * out from under it
1768 */
1769
1770 struct vm_page *
1771 uvm_pagelookup(struct uvm_object *obj, voff_t off)
1772 {
1773 struct vm_page *pg;
1774
1775 /* No - used from DDB. KASSERT(rw_write_held(obj->vmobjlock)); */
1776
1777 pg = radix_tree_lookup_node(&obj->uo_pages, off >> PAGE_SHIFT);
1778
1779 KASSERT(pg == NULL || obj->uo_npages != 0);
1780 KASSERT(pg == NULL || (pg->flags & (PG_RELEASED|PG_PAGEOUT)) == 0 ||
1781 (pg->flags & PG_BUSY) != 0);
1782 return pg;
1783 }
1784
1785 /*
1786 * uvm_pagewire: wire the page, thus removing it from the daemon's grasp
1787 *
1788 * => caller must lock objects
1789 * => caller must hold pg->interlock
1790 */
1791
1792 void
1793 uvm_pagewire(struct vm_page *pg)
1794 {
1795
1796 KASSERT(uvm_page_owner_locked_p(pg, true));
1797 KASSERT(mutex_owned(&pg->interlock));
1798 #if defined(READAHEAD_STATS)
1799 if ((pg->flags & PG_READAHEAD) != 0) {
1800 uvm_ra_hit.ev_count++;
1801 pg->flags &= ~PG_READAHEAD;
1802 }
1803 #endif /* defined(READAHEAD_STATS) */
1804 if (pg->wire_count == 0) {
1805 uvm_pagedequeue(pg);
1806 atomic_inc_uint(&uvmexp.wired);
1807 }
1808 pg->wire_count++;
1809 KASSERT(pg->wire_count > 0); /* detect wraparound */
1810 }
1811
1812 /*
1813 * uvm_pageunwire: unwire the page.
1814 *
1815 * => activate if wire count goes to zero.
1816 * => caller must lock objects
1817 * => caller must hold pg->interlock
1818 */
1819
1820 void
1821 uvm_pageunwire(struct vm_page *pg)
1822 {
1823
1824 KASSERT(uvm_page_owner_locked_p(pg, true));
1825 KASSERT(pg->wire_count != 0);
1826 KASSERT(!uvmpdpol_pageisqueued_p(pg));
1827 KASSERT(mutex_owned(&pg->interlock));
1828 pg->wire_count--;
1829 if (pg->wire_count == 0) {
1830 uvm_pageactivate(pg);
1831 KASSERT(uvmexp.wired != 0);
1832 atomic_dec_uint(&uvmexp.wired);
1833 }
1834 }
1835
1836 /*
1837 * uvm_pagedeactivate: deactivate page
1838 *
1839 * => caller must lock objects
1840 * => caller must check to make sure page is not wired
1841 * => object that page belongs to must be locked (so we can adjust pg->flags)
1842 * => caller must clear the reference on the page before calling
1843 * => caller must hold pg->interlock
1844 */
1845
1846 void
1847 uvm_pagedeactivate(struct vm_page *pg)
1848 {
1849
1850 KASSERT(uvm_page_owner_locked_p(pg, true));
1851 KASSERT(mutex_owned(&pg->interlock));
1852 if (pg->wire_count == 0) {
1853 KASSERT(uvmpdpol_pageisqueued_p(pg));
1854 uvmpdpol_pagedeactivate(pg);
1855 }
1856 }
1857
1858 /*
1859 * uvm_pageactivate: activate page
1860 *
1861 * => caller must lock objects
1862 * => caller must hold pg->interlock
1863 */
1864
1865 void
1866 uvm_pageactivate(struct vm_page *pg)
1867 {
1868
1869 KASSERT(uvm_page_owner_locked_p(pg, true));
1870 KASSERT(mutex_owned(&pg->interlock));
1871 #if defined(READAHEAD_STATS)
1872 if ((pg->flags & PG_READAHEAD) != 0) {
1873 uvm_ra_hit.ev_count++;
1874 pg->flags &= ~PG_READAHEAD;
1875 }
1876 #endif /* defined(READAHEAD_STATS) */
1877 if (pg->wire_count == 0) {
1878 uvmpdpol_pageactivate(pg);
1879 }
1880 }
1881
1882 /*
1883 * uvm_pagedequeue: remove a page from any paging queue
1884 *
1885 * => caller must lock objects
1886 * => caller must hold pg->interlock
1887 */
1888 void
1889 uvm_pagedequeue(struct vm_page *pg)
1890 {
1891
1892 KASSERT(uvm_page_owner_locked_p(pg, true));
1893 KASSERT(mutex_owned(&pg->interlock));
1894 if (uvmpdpol_pageisqueued_p(pg)) {
1895 uvmpdpol_pagedequeue(pg);
1896 }
1897 }
1898
1899 /*
1900 * uvm_pageenqueue: add a page to a paging queue without activating.
1901 * used where a page is not really demanded (yet). eg. read-ahead
1902 *
1903 * => caller must lock objects
1904 * => caller must hold pg->interlock
1905 */
1906 void
1907 uvm_pageenqueue(struct vm_page *pg)
1908 {
1909
1910 KASSERT(uvm_page_owner_locked_p(pg, true));
1911 KASSERT(mutex_owned(&pg->interlock));
1912 if (pg->wire_count == 0 && !uvmpdpol_pageisqueued_p(pg)) {
1913 uvmpdpol_pageenqueue(pg);
1914 }
1915 }
1916
1917 /*
1918 * uvm_pagelock: acquire page interlock
1919 */
1920 void
1921 uvm_pagelock(struct vm_page *pg)
1922 {
1923
1924 mutex_enter(&pg->interlock);
1925 }
1926
1927 /*
1928 * uvm_pagelock2: acquire two page interlocks
1929 */
1930 void
1931 uvm_pagelock2(struct vm_page *pg1, struct vm_page *pg2)
1932 {
1933
1934 if (pg1 < pg2) {
1935 mutex_enter(&pg1->interlock);
1936 mutex_enter(&pg2->interlock);
1937 } else {
1938 mutex_enter(&pg2->interlock);
1939 mutex_enter(&pg1->interlock);
1940 }
1941 }
1942
1943 /*
1944 * uvm_pageunlock: release page interlock, and if a page replacement intent
1945 * is set on the page, pass it to uvmpdpol to make real.
1946 *
1947 * => caller must hold pg->interlock
1948 */
1949 void
1950 uvm_pageunlock(struct vm_page *pg)
1951 {
1952
1953 if ((pg->pqflags & PQ_INTENT_SET) == 0 ||
1954 (pg->pqflags & PQ_INTENT_QUEUED) != 0) {
1955 mutex_exit(&pg->interlock);
1956 return;
1957 }
1958 pg->pqflags |= PQ_INTENT_QUEUED;
1959 mutex_exit(&pg->interlock);
1960 uvmpdpol_pagerealize(pg);
1961 }
1962
1963 /*
1964 * uvm_pageunlock2: release two page interlocks, and for both pages if a
1965 * page replacement intent is set on the page, pass it to uvmpdpol to make
1966 * real.
1967 *
1968 * => caller must hold pg->interlock
1969 */
1970 void
1971 uvm_pageunlock2(struct vm_page *pg1, struct vm_page *pg2)
1972 {
1973
1974 if ((pg1->pqflags & PQ_INTENT_SET) == 0 ||
1975 (pg1->pqflags & PQ_INTENT_QUEUED) != 0) {
1976 mutex_exit(&pg1->interlock);
1977 pg1 = NULL;
1978 } else {
1979 pg1->pqflags |= PQ_INTENT_QUEUED;
1980 mutex_exit(&pg1->interlock);
1981 }
1982
1983 if ((pg2->pqflags & PQ_INTENT_SET) == 0 ||
1984 (pg2->pqflags & PQ_INTENT_QUEUED) != 0) {
1985 mutex_exit(&pg2->interlock);
1986 pg2 = NULL;
1987 } else {
1988 pg2->pqflags |= PQ_INTENT_QUEUED;
1989 mutex_exit(&pg2->interlock);
1990 }
1991
1992 if (pg1 != NULL) {
1993 uvmpdpol_pagerealize(pg1);
1994 }
1995 if (pg2 != NULL) {
1996 uvmpdpol_pagerealize(pg2);
1997 }
1998 }
1999
2000 /*
2001 * uvm_pagezero: zero fill a page
2002 *
2003 * => if page is part of an object then the object should be locked
2004 * to protect pg->flags.
2005 */
2006
2007 void
2008 uvm_pagezero(struct vm_page *pg)
2009 {
2010
2011 uvm_pagemarkdirty(pg, UVM_PAGE_STATUS_DIRTY);
2012 pmap_zero_page(VM_PAGE_TO_PHYS(pg));
2013 }
2014
2015 /*
2016 * uvm_pagecopy: copy a page
2017 *
2018 * => if page is part of an object then the object should be locked
2019 * to protect pg->flags.
2020 */
2021
2022 void
2023 uvm_pagecopy(struct vm_page *src, struct vm_page *dst)
2024 {
2025
2026 uvm_pagemarkdirty(dst, UVM_PAGE_STATUS_DIRTY);
2027 pmap_copy_page(VM_PAGE_TO_PHYS(src), VM_PAGE_TO_PHYS(dst));
2028 }
2029
2030 /*
2031 * uvm_pageismanaged: test it see that a page (specified by PA) is managed.
2032 */
2033
2034 bool
2035 uvm_pageismanaged(paddr_t pa)
2036 {
2037
2038 return (uvm_physseg_find(atop(pa), NULL) != UVM_PHYSSEG_TYPE_INVALID);
2039 }
2040
2041 /*
2042 * uvm_page_lookup_freelist: look up the free list for the specified page
2043 */
2044
2045 int
2046 uvm_page_lookup_freelist(struct vm_page *pg)
2047 {
2048 uvm_physseg_t upm;
2049
2050 upm = uvm_physseg_find(atop(VM_PAGE_TO_PHYS(pg)), NULL);
2051 KASSERT(upm != UVM_PHYSSEG_TYPE_INVALID);
2052 return uvm_physseg_get_free_list(upm);
2053 }
2054
2055 /*
2056 * uvm_page_owner_locked_p: return true if object associated with page is
2057 * locked. this is a weak check for runtime assertions only.
2058 */
2059
2060 bool
2061 uvm_page_owner_locked_p(struct vm_page *pg, bool exclusive)
2062 {
2063
2064 if (pg->uobject != NULL) {
2065 return exclusive
2066 ? rw_write_held(pg->uobject->vmobjlock)
2067 : rw_lock_held(pg->uobject->vmobjlock);
2068 }
2069 if (pg->uanon != NULL) {
2070 return exclusive
2071 ? rw_write_held(pg->uanon->an_lock)
2072 : rw_lock_held(pg->uanon->an_lock);
2073 }
2074 return true;
2075 }
2076
2077 /*
2078 * uvm_pagereadonly_p: return if the page should be mapped read-only
2079 */
2080
2081 bool
2082 uvm_pagereadonly_p(struct vm_page *pg)
2083 {
2084 struct uvm_object * const uobj = pg->uobject;
2085
2086 KASSERT(uobj == NULL || rw_lock_held(uobj->vmobjlock));
2087 KASSERT(uobj != NULL || rw_lock_held(pg->uanon->an_lock));
2088 if ((pg->flags & PG_RDONLY) != 0) {
2089 return true;
2090 }
2091 if (uvm_pagegetdirty(pg) == UVM_PAGE_STATUS_CLEAN) {
2092 return true;
2093 }
2094 if (uobj == NULL) {
2095 return false;
2096 }
2097 return UVM_OBJ_NEEDS_WRITEFAULT(uobj);
2098 }
2099
2100 #ifdef PMAP_DIRECT
2101 /*
2102 * Call pmap to translate physical address into a virtual and to run a callback
2103 * for it. Used to avoid actually mapping the pages, pmap most likely uses direct map
2104 * or equivalent.
2105 */
2106 int
2107 uvm_direct_process(struct vm_page **pgs, u_int npages, voff_t off, vsize_t len,
2108 int (*process)(void *, size_t, void *), void *arg)
2109 {
2110 int error = 0;
2111 paddr_t pa;
2112 size_t todo;
2113 voff_t pgoff = (off & PAGE_MASK);
2114 struct vm_page *pg;
2115
2116 KASSERT(npages > 0 && len > 0);
2117
2118 for (int i = 0; i < npages; i++) {
2119 pg = pgs[i];
2120
2121 KASSERT(len > 0);
2122
2123 /*
2124 * Caller is responsible for ensuring all the pages are
2125 * available.
2126 */
2127 KASSERT(pg != NULL && pg != PGO_DONTCARE);
2128
2129 pa = VM_PAGE_TO_PHYS(pg);
2130 todo = MIN(len, PAGE_SIZE - pgoff);
2131
2132 error = pmap_direct_process(pa, pgoff, todo, process, arg);
2133 if (error)
2134 break;
2135
2136 pgoff = 0;
2137 len -= todo;
2138 }
2139
2140 KASSERTMSG(error != 0 || len == 0, "len %lu != 0 for non-error", len);
2141 return error;
2142 }
2143 #endif /* PMAP_DIRECT */
2144
2145 #if defined(DDB) || defined(DEBUGPRINT)
2146
2147 /*
2148 * uvm_page_printit: actually print the page
2149 */
2150
2151 static const char page_flagbits[] = UVM_PGFLAGBITS;
2152 static const char page_pqflagbits[] = UVM_PQFLAGBITS;
2153
2154 void
2155 uvm_page_printit(struct vm_page *pg, bool full,
2156 void (*pr)(const char *, ...))
2157 {
2158 struct vm_page *tpg;
2159 struct uvm_object *uobj;
2160 struct pgflbucket *pgb;
2161 struct pgflist *pgl;
2162 char pgbuf[128];
2163
2164 (*pr)("PAGE %p:\n", pg);
2165 snprintb(pgbuf, sizeof(pgbuf), page_flagbits, pg->flags);
2166 (*pr)(" flags=%s\n", pgbuf);
2167 snprintb(pgbuf, sizeof(pgbuf), page_pqflagbits, pg->pqflags);
2168 (*pr)(" pqflags=%s\n", pgbuf);
2169 (*pr)(" uobject=%p, uanon=%p, offset=0x%llx\n",
2170 pg->uobject, pg->uanon, (long long)pg->offset);
2171 (*pr)(" loan_count=%d wire_count=%d bucket=%d freelist=%d\n",
2172 pg->loan_count, pg->wire_count, uvm_page_get_bucket(pg),
2173 uvm_page_get_freelist(pg));
2174 (*pr)(" pa=0x%lx\n", (long)VM_PAGE_TO_PHYS(pg));
2175 #if defined(UVM_PAGE_TRKOWN)
2176 if (pg->flags & PG_BUSY)
2177 (*pr)(" owning process = %d, tag=%s\n",
2178 pg->owner, pg->owner_tag);
2179 else
2180 (*pr)(" page not busy, no owner\n");
2181 #else
2182 (*pr)(" [page ownership tracking disabled]\n");
2183 #endif
2184
2185 if (!full)
2186 return;
2187
2188 /* cross-verify object/anon */
2189 if ((pg->flags & PG_FREE) == 0) {
2190 if (pg->flags & PG_ANON) {
2191 if (pg->uanon == NULL || pg->uanon->an_page != pg)
2192 (*pr)(" >>> ANON DOES NOT POINT HERE <<< (%p)\n",
2193 (pg->uanon) ? pg->uanon->an_page : NULL);
2194 else
2195 (*pr)(" anon backpointer is OK\n");
2196 } else {
2197 uobj = pg->uobject;
2198 if (uobj) {
2199 (*pr)(" checking object list\n");
2200 tpg = uvm_pagelookup(uobj, pg->offset);
2201 if (tpg)
2202 (*pr)(" page found on object list\n");
2203 else
2204 (*pr)(" >>> PAGE NOT FOUND ON OBJECT LIST! <<<\n");
2205 }
2206 }
2207 }
2208
2209 /* cross-verify page queue */
2210 if (pg->flags & PG_FREE) {
2211 int fl = uvm_page_get_freelist(pg);
2212 int b = uvm_page_get_bucket(pg);
2213 pgb = uvm.page_free[fl].pgfl_buckets[b];
2214 pgl = &pgb->pgb_colors[VM_PGCOLOR(pg)];
2215 (*pr)(" checking pageq list\n");
2216 LIST_FOREACH(tpg, pgl, pageq.list) {
2217 if (tpg == pg) {
2218 break;
2219 }
2220 }
2221 if (tpg)
2222 (*pr)(" page found on pageq list\n");
2223 else
2224 (*pr)(" >>> PAGE NOT FOUND ON PAGEQ LIST! <<<\n");
2225 }
2226 }
2227
2228 /*
2229 * uvm_page_printall - print a summary of all managed pages
2230 */
2231
2232 void
2233 uvm_page_printall(void (*pr)(const char *, ...))
2234 {
2235 uvm_physseg_t i;
2236 paddr_t pfn;
2237 struct vm_page *pg;
2238
2239 (*pr)("%18s %4s %4s %18s %18s"
2240 #ifdef UVM_PAGE_TRKOWN
2241 " OWNER"
2242 #endif
2243 "\n", "PAGE", "FLAG", "PQ", "UOBJECT", "UANON");
2244 for (i = uvm_physseg_get_first();
2245 uvm_physseg_valid_p(i);
2246 i = uvm_physseg_get_next(i)) {
2247 for (pfn = uvm_physseg_get_start(i);
2248 pfn < uvm_physseg_get_end(i);
2249 pfn++) {
2250 pg = PHYS_TO_VM_PAGE(ptoa(pfn));
2251
2252 (*pr)("%18p %04x %08x %18p %18p",
2253 pg, pg->flags, pg->pqflags, pg->uobject,
2254 pg->uanon);
2255 #ifdef UVM_PAGE_TRKOWN
2256 if (pg->flags & PG_BUSY)
2257 (*pr)(" %d [%s]", pg->owner, pg->owner_tag);
2258 #endif
2259 (*pr)("\n");
2260 }
2261 }
2262 }
2263
2264 /*
2265 * uvm_page_print_freelists - print a summary freelists
2266 */
2267
2268 void
2269 uvm_page_print_freelists(void (*pr)(const char *, ...))
2270 {
2271 struct pgfreelist *pgfl;
2272 struct pgflbucket *pgb;
2273 int fl, b, c;
2274
2275 (*pr)("There are %d freelists with %d buckets of %d colors.\n\n",
2276 VM_NFREELIST, uvm.bucketcount, uvmexp.ncolors);
2277
2278 for (fl = 0; fl < VM_NFREELIST; fl++) {
2279 pgfl = &uvm.page_free[fl];
2280 (*pr)("freelist(%d) @ %p\n", fl, pgfl);
2281 for (b = 0; b < uvm.bucketcount; b++) {
2282 pgb = uvm.page_free[fl].pgfl_buckets[b];
2283 (*pr)(" bucket(%d) @ %p, nfree = %d, lock @ %p:\n",
2284 b, pgb, pgb->pgb_nfree,
2285 &uvm_freelist_locks[b].lock);
2286 for (c = 0; c < uvmexp.ncolors; c++) {
2287 (*pr)(" color(%d) @ %p, ", c,
2288 &pgb->pgb_colors[c]);
2289 (*pr)("first page = %p\n",
2290 LIST_FIRST(&pgb->pgb_colors[c]));
2291 }
2292 }
2293 }
2294 }
2295
2296 #endif /* DDB || DEBUGPRINT */
2297