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1/*
2 * Copyright (c) Red Hat Inc.
3
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sub license,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the
12 * next paragraph) shall be included in all copies or substantial portions
13 * of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Authors: Dave Airlie <airlied@redhat.com>
24 * Jerome Glisse <jglisse@redhat.com>
25 * Pauli Nieminen <suokkos@gmail.com>
26 */
27
28/* simple list based uncached page pool
29 * - Pool collects resently freed pages for reuse
30 * - Use page->lru to keep a free list
31 * - doesn't track currently in use pages
32 */
33
34#define pr_fmt(fmt) "[TTM] " fmt
35
36#include <linux/list.h>
37#include <linux/spinlock.h>
38#include <linux/highmem.h>
39#include <linux/mm_types.h>
40#include <linux/module.h>
41#include <linux/mm.h>
42#include <linux/seq_file.h> /* for seq_printf */
43#include <linux/slab.h>
44#include <linux/dma-mapping.h>
45
46#include <linux/atomic.h>
47
48#include "ttm/ttm_bo_driver.h"
49#include "ttm/ttm_page_alloc.h"
50
51#ifdef TTM_HAS_AGP
52#include <asm/agp.h>
53#endif
54
55#define NUM_PAGES_TO_ALLOC (PAGE_SIZE/sizeof(struct page *))
56#define SMALL_ALLOCATION 16
57#define FREE_ALL_PAGES (~0U)
58/* times are in msecs */
59#define PAGE_FREE_INTERVAL 1000
60
61/**
62 * struct ttm_page_pool - Pool to reuse recently allocated uc/wc pages.
63 *
64 * @lock: Protects the shared pool from concurrnet access. Must be used with
65 * irqsave/irqrestore variants because pool allocator maybe called from
66 * delayed work.
67 * @fill_lock: Prevent concurrent calls to fill.
68 * @list: Pool of free uc/wc pages for fast reuse.
69 * @gfp_flags: Flags to pass for alloc_page.
70 * @npages: Number of pages in pool.
71 */
72struct ttm_page_pool {
73 spinlock_t lock;
74 bool fill_lock;
75 struct list_head list;
76 gfp_t gfp_flags;
77 unsigned npages;
78 char *name;
79 unsigned long nfrees;
80 unsigned long nrefills;
81};
82
83/**
84 * Limits for the pool. They are handled without locks because only place where
85 * they may change is in sysfs store. They won't have immediate effect anyway
86 * so forcing serialization to access them is pointless.
87 */
88
89struct ttm_pool_opts {
90 unsigned alloc_size;
91 unsigned max_size;
92 unsigned small;
93};
94
95#define NUM_POOLS 4
96
97/**
98 * struct ttm_pool_manager - Holds memory pools for fst allocation
99 *
100 * Manager is read only object for pool code so it doesn't need locking.
101 *
102 * @free_interval: minimum number of jiffies between freeing pages from pool.
103 * @page_alloc_inited: reference counting for pool allocation.
104 * @work: Work that is used to shrink the pool. Work is only run when there is
105 * some pages to free.
106 * @small_allocation: Limit in number of pages what is small allocation.
107 *
108 * @pools: All pool objects in use.
109 **/
110struct ttm_pool_manager {
111 struct kobject kobj;
112 struct shrinker mm_shrink;
113 struct ttm_pool_opts options;
114
115 union {
116 struct ttm_page_pool pools[NUM_POOLS];
117 struct {
118 struct ttm_page_pool wc_pool;
119 struct ttm_page_pool uc_pool;
120 struct ttm_page_pool wc_pool_dma32;
121 struct ttm_page_pool uc_pool_dma32;
122 } ;
123 };
124};
125
126static struct attribute ttm_page_pool_max = {
127 .name = "pool_max_size",
128 .mode = S_IRUGO | S_IWUSR
129};
130static struct attribute ttm_page_pool_small = {
131 .name = "pool_small_allocation",
132 .mode = S_IRUGO | S_IWUSR
133};
134static struct attribute ttm_page_pool_alloc_size = {
135 .name = "pool_allocation_size",
136 .mode = S_IRUGO | S_IWUSR
137};
138
139static struct attribute *ttm_pool_attrs[] = {
140 &ttm_page_pool_max,
141 &ttm_page_pool_small,
142 &ttm_page_pool_alloc_size,
143 NULL
144};
145
146static void ttm_pool_kobj_release(struct kobject *kobj)
147{
148 struct ttm_pool_manager *m =
149 container_of(kobj, struct ttm_pool_manager, kobj);
150 kfree(m);
151}
152
153static ssize_t ttm_pool_store(struct kobject *kobj,
154 struct attribute *attr, const char *buffer, size_t size)
155{
156 struct ttm_pool_manager *m =
157 container_of(kobj, struct ttm_pool_manager, kobj);
158 int chars;
159 unsigned val;
160 chars = sscanf(buffer, "%u", &val);
161 if (chars == 0)
162 return size;
163
164 /* Convert kb to number of pages */
165 val = val / (PAGE_SIZE >> 10);
166
167 if (attr == &ttm_page_pool_max)
168 m->options.max_size = val;
169 else if (attr == &ttm_page_pool_small)
170 m->options.small = val;
171 else if (attr == &ttm_page_pool_alloc_size) {
172 if (val > NUM_PAGES_TO_ALLOC*8) {
173 pr_err("Setting allocation size to %lu is not allowed. Recommended size is %lu\n",
174 NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 7),
175 NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 10));
176 return size;
177 } else if (val > NUM_PAGES_TO_ALLOC) {
178 pr_warn("Setting allocation size to larger than %lu is not recommended\n",
179 NUM_PAGES_TO_ALLOC*(PAGE_SIZE >> 10));
180 }
181 m->options.alloc_size = val;
182 }
183
184 return size;
185}
186
187static ssize_t ttm_pool_show(struct kobject *kobj,
188 struct attribute *attr, char *buffer)
189{
190 struct ttm_pool_manager *m =
191 container_of(kobj, struct ttm_pool_manager, kobj);
192 unsigned val = 0;
193
194 if (attr == &ttm_page_pool_max)
195 val = m->options.max_size;
196 else if (attr == &ttm_page_pool_small)
197 val = m->options.small;
198 else if (attr == &ttm_page_pool_alloc_size)
199 val = m->options.alloc_size;
200
201 val = val * (PAGE_SIZE >> 10);
202
203 return snprintf(buffer, PAGE_SIZE, "%u\n", val);
204}
205
206static const struct sysfs_ops ttm_pool_sysfs_ops = {
207 .show = &ttm_pool_show,
208 .store = &ttm_pool_store,
209};
210
211static struct kobj_type ttm_pool_kobj_type = {
212 .release = &ttm_pool_kobj_release,
213 .sysfs_ops = &ttm_pool_sysfs_ops,
214 .default_attrs = ttm_pool_attrs,
215};
216
217static struct ttm_pool_manager *_manager;
218
219#ifndef CONFIG_X86
220static int set_pages_array_wb(struct page **pages, int addrinarray)
221{
222#ifdef TTM_HAS_AGP
223 int i;
224
225 for (i = 0; i < addrinarray; i++)
226 unmap_page_from_agp(pages[i]);
227#endif
228 return 0;
229}
230
231static int set_pages_array_wc(struct page **pages, int addrinarray)
232{
233#ifdef TTM_HAS_AGP
234 int i;
235
236 for (i = 0; i < addrinarray; i++)
237 map_page_into_agp(pages[i]);
238#endif
239 return 0;
240}
241
242static int set_pages_array_uc(struct page **pages, int addrinarray)
243{
244#ifdef TTM_HAS_AGP
245 int i;
246
247 for (i = 0; i < addrinarray; i++)
248 map_page_into_agp(pages[i]);
249#endif
250 return 0;
251}
252#endif
253
254/**
255 * Select the right pool or requested caching state and ttm flags. */
256static struct ttm_page_pool *ttm_get_pool(int flags,
257 enum ttm_caching_state cstate)
258{
259 int pool_index;
260
261 if (cstate == tt_cached)
262 return NULL;
263
264 if (cstate == tt_wc)
265 pool_index = 0x0;
266 else
267 pool_index = 0x1;
268
269 if (flags & TTM_PAGE_FLAG_DMA32)
270 pool_index |= 0x2;
271
272 return &_manager->pools[pool_index];
273}
274
275/* set memory back to wb and free the pages. */
276static void ttm_pages_put(struct page *pages[], unsigned npages)
277{
278 unsigned i;
279 if (set_pages_array_wb(pages, npages))
280 pr_err("Failed to set %d pages to wb!\n", npages);
281 for (i = 0; i < npages; ++i)
282 __free_page(pages[i]);
283}
284
285static void ttm_pool_update_free_locked(struct ttm_page_pool *pool,
286 unsigned freed_pages)
287{
288 pool->npages -= freed_pages;
289 pool->nfrees += freed_pages;
290}
291
292/**
293 * Free pages from pool.
294 *
295 * To prevent hogging the ttm_swap process we only free NUM_PAGES_TO_ALLOC
296 * number of pages in one go.
297 *
298 * @pool: to free the pages from
299 * @free_all: If set to true will free all pages in pool
300 **/
301static int ttm_page_pool_free(struct ttm_page_pool *pool, unsigned nr_free)
302{
303 unsigned long irq_flags;
304 struct page *p;
305 struct page **pages_to_free;
306 unsigned freed_pages = 0,
307 npages_to_free = nr_free;
308
309 if (NUM_PAGES_TO_ALLOC < nr_free)
310 npages_to_free = NUM_PAGES_TO_ALLOC;
311
312 pages_to_free = kmalloc(npages_to_free * sizeof(struct page *),
313 GFP_KERNEL);
314 if (!pages_to_free) {
315 pr_err("Failed to allocate memory for pool free operation\n");
316 return 0;
317 }
318
319restart:
320 spin_lock_irqsave(&pool->lock, irq_flags);
321
322 list_for_each_entry_reverse(p, &pool->list, lru) {
323 if (freed_pages >= npages_to_free)
324 break;
325
326 pages_to_free[freed_pages++] = p;
327 /* We can only remove NUM_PAGES_TO_ALLOC at a time. */
328 if (freed_pages >= NUM_PAGES_TO_ALLOC) {
329 /* remove range of pages from the pool */
330 __list_del(p->lru.prev, &pool->list);
331
332 ttm_pool_update_free_locked(pool, freed_pages);
333 /**
334 * Because changing page caching is costly
335 * we unlock the pool to prevent stalling.
336 */
337 spin_unlock_irqrestore(&pool->lock, irq_flags);
338
339 ttm_pages_put(pages_to_free, freed_pages);
340 if (likely(nr_free != FREE_ALL_PAGES))
341 nr_free -= freed_pages;
342
343 if (NUM_PAGES_TO_ALLOC >= nr_free)
344 npages_to_free = nr_free;
345 else
346 npages_to_free = NUM_PAGES_TO_ALLOC;
347
348 freed_pages = 0;
349
350 /* free all so restart the processing */
351 if (nr_free)
352 goto restart;
353
354 /* Not allowed to fall through or break because
355 * following context is inside spinlock while we are
356 * outside here.
357 */
358 goto out;
359
360 }
361 }
362
363 /* remove range of pages from the pool */
364 if (freed_pages) {
365 __list_del(&p->lru, &pool->list);
366
367 ttm_pool_update_free_locked(pool, freed_pages);
368 nr_free -= freed_pages;
369 }
370
371 spin_unlock_irqrestore(&pool->lock, irq_flags);
372
373 if (freed_pages)
374 ttm_pages_put(pages_to_free, freed_pages);
375out:
376 kfree(pages_to_free);
377 return nr_free;
378}
379
380/* Get good estimation how many pages are free in pools */
381static int ttm_pool_get_num_unused_pages(void)
382{
383 unsigned i;
384 int total = 0;
385 for (i = 0; i < NUM_POOLS; ++i)
386 total += _manager->pools[i].npages;
387
388 return total;
389}
390
391/**
392 * Callback for mm to request pool to reduce number of page held.
393 */
394static int ttm_pool_mm_shrink(struct shrinker *shrink,
395 struct shrink_control *sc)
396{
397 static atomic_t start_pool = ATOMIC_INIT(0);
398 unsigned i;
399 unsigned pool_offset = atomic_add_return(1, &start_pool);
400 struct ttm_page_pool *pool;
401 int shrink_pages = sc->nr_to_scan;
402
403 pool_offset = pool_offset % NUM_POOLS;
404 /* select start pool in round robin fashion */
405 for (i = 0; i < NUM_POOLS; ++i) {
406 unsigned nr_free = shrink_pages;
407 if (shrink_pages == 0)
408 break;
409 pool = &_manager->pools[(i + pool_offset)%NUM_POOLS];
410 shrink_pages = ttm_page_pool_free(pool, nr_free);
411 }
412 /* return estimated number of unused pages in pool */
413 return ttm_pool_get_num_unused_pages();
414}
415
416static void ttm_pool_mm_shrink_init(struct ttm_pool_manager *manager)
417{
418 manager->mm_shrink.shrink = &ttm_pool_mm_shrink;
419 manager->mm_shrink.seeks = 1;
420 register_shrinker(&manager->mm_shrink);
421}
422
423static void ttm_pool_mm_shrink_fini(struct ttm_pool_manager *manager)
424{
425 unregister_shrinker(&manager->mm_shrink);
426}
427
428static int ttm_set_pages_caching(struct page **pages,
429 enum ttm_caching_state cstate, unsigned cpages)
430{
431 int r = 0;
432 /* Set page caching */
433 switch (cstate) {
434 case tt_uncached:
435 r = set_pages_array_uc(pages, cpages);
436 if (r)
437 pr_err("Failed to set %d pages to uc!\n", cpages);
438 break;
439 case tt_wc:
440 r = set_pages_array_wc(pages, cpages);
441 if (r)
442 pr_err("Failed to set %d pages to wc!\n", cpages);
443 break;
444 default:
445 break;
446 }
447 return r;
448}
449
450/**
451 * Free pages the pages that failed to change the caching state. If there is
452 * any pages that have changed their caching state already put them to the
453 * pool.
454 */
455static void ttm_handle_caching_state_failure(struct list_head *pages,
456 int ttm_flags, enum ttm_caching_state cstate,
457 struct page **failed_pages, unsigned cpages)
458{
459 unsigned i;
460 /* Failed pages have to be freed */
461 for (i = 0; i < cpages; ++i) {
462 list_del(&failed_pages[i]->lru);
463 __free_page(failed_pages[i]);
464 }
465}
466
467/**
468 * Allocate new pages with correct caching.
469 *
470 * This function is reentrant if caller updates count depending on number of
471 * pages returned in pages array.
472 */
473static int ttm_alloc_new_pages(struct list_head *pages, gfp_t gfp_flags,
474 int ttm_flags, enum ttm_caching_state cstate, unsigned count)
475{
476 struct page **caching_array;
477 struct page *p;
478 int r = 0;
479 unsigned i, cpages;
480 unsigned max_cpages = min(count,
481 (unsigned)(PAGE_SIZE/sizeof(struct page *)));
482
483 /* allocate array for page caching change */
484 caching_array = kmalloc(max_cpages*sizeof(struct page *), GFP_KERNEL);
485
486 if (!caching_array) {
487 pr_err("Unable to allocate table for new pages\n");
488 return -ENOMEM;
489 }
490
491 for (i = 0, cpages = 0; i < count; ++i) {
492 p = alloc_page(gfp_flags);
493
494 if (!p) {
495 pr_err("Unable to get page %u\n", i);
496
497 /* store already allocated pages in the pool after
498 * setting the caching state */
499 if (cpages) {
500 r = ttm_set_pages_caching(caching_array,
501 cstate, cpages);
502 if (r)
503 ttm_handle_caching_state_failure(pages,
504 ttm_flags, cstate,
505 caching_array, cpages);
506 }
507 r = -ENOMEM;
508 goto out;
509 }
510
511#ifdef CONFIG_HIGHMEM
512 /* gfp flags of highmem page should never be dma32 so we
513 * we should be fine in such case
514 */
515 if (!PageHighMem(p))
516#endif
517 {
518 caching_array[cpages++] = p;
519 if (cpages == max_cpages) {
520
521 r = ttm_set_pages_caching(caching_array,
522 cstate, cpages);
523 if (r) {
524 ttm_handle_caching_state_failure(pages,
525 ttm_flags, cstate,
526 caching_array, cpages);
527 goto out;
528 }
529 cpages = 0;
530 }
531 }
532
533 list_add(&p->lru, pages);
534 }
535
536 if (cpages) {
537 r = ttm_set_pages_caching(caching_array, cstate, cpages);
538 if (r)
539 ttm_handle_caching_state_failure(pages,
540 ttm_flags, cstate,
541 caching_array, cpages);
542 }
543out:
544 kfree(caching_array);
545
546 return r;
547}
548
549/**
550 * Fill the given pool if there aren't enough pages and the requested number of
551 * pages is small.
552 */
553static void ttm_page_pool_fill_locked(struct ttm_page_pool *pool,
554 int ttm_flags, enum ttm_caching_state cstate, unsigned count,
555 unsigned long *irq_flags)
556{
557 struct page *p;
558 int r;
559 unsigned cpages = 0;
560 /**
561 * Only allow one pool fill operation at a time.
562 * If pool doesn't have enough pages for the allocation new pages are
563 * allocated from outside of pool.
564 */
565 if (pool->fill_lock)
566 return;
567
568 pool->fill_lock = true;
569
570 /* If allocation request is small and there are not enough
571 * pages in a pool we fill the pool up first. */
572 if (count < _manager->options.small
573 && count > pool->npages) {
574 struct list_head new_pages;
575 unsigned alloc_size = _manager->options.alloc_size;
576
577 /**
578 * Can't change page caching if in irqsave context. We have to
579 * drop the pool->lock.
580 */
581 spin_unlock_irqrestore(&pool->lock, *irq_flags);
582
583 INIT_LIST_HEAD(&new_pages);
584 r = ttm_alloc_new_pages(&new_pages, pool->gfp_flags, ttm_flags,
585 cstate, alloc_size);
586 spin_lock_irqsave(&pool->lock, *irq_flags);
587
588 if (!r) {
589 list_splice(&new_pages, &pool->list);
590 ++pool->nrefills;
591 pool->npages += alloc_size;
592 } else {
593 pr_err("Failed to fill pool (%p)\n", pool);
594 /* If we have any pages left put them to the pool. */
595 list_for_each_entry(p, &pool->list, lru) {
596 ++cpages;
597 }
598 list_splice(&new_pages, &pool->list);
599 pool->npages += cpages;
600 }
601
602 }
603 pool->fill_lock = false;
604}
605
606/**
607 * Cut 'count' number of pages from the pool and put them on the return list.
608 *
609 * @return count of pages still required to fulfill the request.
610 */
611static unsigned ttm_page_pool_get_pages(struct ttm_page_pool *pool,
612 struct list_head *pages,
613 int ttm_flags,
614 enum ttm_caching_state cstate,
615 unsigned count)
616{
617 unsigned long irq_flags;
618 struct list_head *p;
619 unsigned i;
620
621 spin_lock_irqsave(&pool->lock, irq_flags);
622 ttm_page_pool_fill_locked(pool, ttm_flags, cstate, count, &irq_flags);
623
624 if (count >= pool->npages) {
625 /* take all pages from the pool */
626 list_splice_init(&pool->list, pages);
627 count -= pool->npages;
628 pool->npages = 0;
629 goto out;
630 }
631 /* find the last pages to include for requested number of pages. Split
632 * pool to begin and halve it to reduce search space. */
633 if (count <= pool->npages/2) {
634 i = 0;
635 list_for_each(p, &pool->list) {
636 if (++i == count)
637 break;
638 }
639 } else {
640 i = pool->npages + 1;
641 list_for_each_prev(p, &pool->list) {
642 if (--i == count)
643 break;
644 }
645 }
646 /* Cut 'count' number of pages from the pool */
647 list_cut_position(pages, &pool->list, p);
648 pool->npages -= count;
649 count = 0;
650out:
651 spin_unlock_irqrestore(&pool->lock, irq_flags);
652 return count;
653}
654
655/* Put all pages in pages list to correct pool to wait for reuse */
656static void ttm_put_pages(struct page **pages, unsigned npages, int flags,
657 enum ttm_caching_state cstate)
658{
659 unsigned long irq_flags;
660 struct ttm_page_pool *pool = ttm_get_pool(flags, cstate);
661 unsigned i;
662
663 if (pool == NULL) {
664 /* No pool for this memory type so free the pages */
665 for (i = 0; i < npages; i++) {
666 if (pages[i]) {
667 if (page_count(pages[i]) != 1)
668 pr_err("Erroneous page count. Leaking pages.\n");
669 __free_page(pages[i]);
670 pages[i] = NULL;
671 }
672 }
673 return;
674 }
675
676 spin_lock_irqsave(&pool->lock, irq_flags);
677 for (i = 0; i < npages; i++) {
678 if (pages[i]) {
679 if (page_count(pages[i]) != 1)
680 pr_err("Erroneous page count. Leaking pages.\n");
681 list_add_tail(&pages[i]->lru, &pool->list);
682 pages[i] = NULL;
683 pool->npages++;
684 }
685 }
686 /* Check that we don't go over the pool limit */
687 npages = 0;
688 if (pool->npages > _manager->options.max_size) {
689 npages = pool->npages - _manager->options.max_size;
690 /* free at least NUM_PAGES_TO_ALLOC number of pages
691 * to reduce calls to set_memory_wb */
692 if (npages < NUM_PAGES_TO_ALLOC)
693 npages = NUM_PAGES_TO_ALLOC;
694 }
695 spin_unlock_irqrestore(&pool->lock, irq_flags);
696 if (npages)
697 ttm_page_pool_free(pool, npages);
698}
699
700/*
701 * On success pages list will hold count number of correctly
702 * cached pages.
703 */
704static int ttm_get_pages(struct page **pages, unsigned npages, int flags,
705 enum ttm_caching_state cstate)
706{
707 struct ttm_page_pool *pool = ttm_get_pool(flags, cstate);
708 struct list_head plist;
709 struct page *p = NULL;
710 gfp_t gfp_flags = GFP_USER;
711 unsigned count;
712 int r;
713
714 /* set zero flag for page allocation if required */
715 if (flags & TTM_PAGE_FLAG_ZERO_ALLOC)
716 gfp_flags |= __GFP_ZERO;
717
718 /* No pool for cached pages */
719 if (pool == NULL) {
720 if (flags & TTM_PAGE_FLAG_DMA32)
721 gfp_flags |= GFP_DMA32;
722 else
723 gfp_flags |= GFP_HIGHUSER;
724
725 for (r = 0; r < npages; ++r) {
726 p = alloc_page(gfp_flags);
727 if (!p) {
728
729 pr_err("Unable to allocate page\n");
730 return -ENOMEM;
731 }
732
733 pages[r] = p;
734 }
735 return 0;
736 }
737
738 /* combine zero flag to pool flags */
739 gfp_flags |= pool->gfp_flags;
740
741 /* First we take pages from the pool */
742 INIT_LIST_HEAD(&plist);
743 npages = ttm_page_pool_get_pages(pool, &plist, flags, cstate, npages);
744 count = 0;
745 list_for_each_entry(p, &plist, lru) {
746 pages[count++] = p;
747 }
748
749 /* clear the pages coming from the pool if requested */
750 if (flags & TTM_PAGE_FLAG_ZERO_ALLOC) {
751 list_for_each_entry(p, &plist, lru) {
752 clear_page(page_address(p));
753 }
754 }
755
756 /* If pool didn't have enough pages allocate new one. */
757 if (npages > 0) {
758 /* ttm_alloc_new_pages doesn't reference pool so we can run
759 * multiple requests in parallel.
760 **/
761 INIT_LIST_HEAD(&plist);
762 r = ttm_alloc_new_pages(&plist, gfp_flags, flags, cstate, npages);
763 list_for_each_entry(p, &plist, lru) {
764 pages[count++] = p;
765 }
766 if (r) {
767 /* If there is any pages in the list put them back to
768 * the pool. */
769 pr_err("Failed to allocate extra pages for large request\n");
770 ttm_put_pages(pages, count, flags, cstate);
771 return r;
772 }
773 }
774
775 return 0;
776}
777
778static void ttm_page_pool_init_locked(struct ttm_page_pool *pool, int flags,
779 char *name)
780{
781 spin_lock_init(&pool->lock);
782 pool->fill_lock = false;
783 INIT_LIST_HEAD(&pool->list);
784 pool->npages = pool->nfrees = 0;
785 pool->gfp_flags = flags;
786 pool->name = name;
787}
788
789int ttm_page_alloc_init(struct ttm_mem_global *glob, unsigned max_pages)
790{
791 int ret;
792
793 WARN_ON(_manager);
794
795 pr_info("Initializing pool allocator\n");
796
797 _manager = kzalloc(sizeof(*_manager), GFP_KERNEL);
798
799 ttm_page_pool_init_locked(&_manager->wc_pool, GFP_HIGHUSER, "wc");
800
801 ttm_page_pool_init_locked(&_manager->uc_pool, GFP_HIGHUSER, "uc");
802
803 ttm_page_pool_init_locked(&_manager->wc_pool_dma32,
804 GFP_USER | GFP_DMA32, "wc dma");
805
806 ttm_page_pool_init_locked(&_manager->uc_pool_dma32,
807 GFP_USER | GFP_DMA32, "uc dma");
808
809 _manager->options.max_size = max_pages;
810 _manager->options.small = SMALL_ALLOCATION;
811 _manager->options.alloc_size = NUM_PAGES_TO_ALLOC;
812
813 ret = kobject_init_and_add(&_manager->kobj, &ttm_pool_kobj_type,
814 &glob->kobj, "pool");
815 if (unlikely(ret != 0)) {
816 kobject_put(&_manager->kobj);
817 _manager = NULL;
818 return ret;
819 }
820
821 ttm_pool_mm_shrink_init(_manager);
822
823 return 0;
824}
825
826void ttm_page_alloc_fini(void)
827{
828 int i;
829
830 pr_info("Finalizing pool allocator\n");
831 ttm_pool_mm_shrink_fini(_manager);
832
833 for (i = 0; i < NUM_POOLS; ++i)
834 ttm_page_pool_free(&_manager->pools[i], FREE_ALL_PAGES);
835
836 kobject_put(&_manager->kobj);
837 _manager = NULL;
838}
839
840int ttm_pool_populate(struct ttm_tt *ttm)
841{
842 struct ttm_mem_global *mem_glob = ttm->glob->mem_glob;
843 unsigned i;
844 int ret;
845
846 if (ttm->state != tt_unpopulated)
847 return 0;
848
849 for (i = 0; i < ttm->num_pages; ++i) {
850 ret = ttm_get_pages(&ttm->pages[i], 1,
851 ttm->page_flags,
852 ttm->caching_state);
853 if (ret != 0) {
854 ttm_pool_unpopulate(ttm);
855 return -ENOMEM;
856 }
857
858 ret = ttm_mem_global_alloc_page(mem_glob, ttm->pages[i],
859 false, false);
860 if (unlikely(ret != 0)) {
861 ttm_pool_unpopulate(ttm);
862 return -ENOMEM;
863 }
864 }
865
866 if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
867 ret = ttm_tt_swapin(ttm);
868 if (unlikely(ret != 0)) {
869 ttm_pool_unpopulate(ttm);
870 return ret;
871 }
872 }
873
874 ttm->state = tt_unbound;
875 return 0;
876}
877EXPORT_SYMBOL(ttm_pool_populate);
878
879void ttm_pool_unpopulate(struct ttm_tt *ttm)
880{
881 unsigned i;
882
883 for (i = 0; i < ttm->num_pages; ++i) {
884 if (ttm->pages[i]) {
885 ttm_mem_global_free_page(ttm->glob->mem_glob,
886 ttm->pages[i]);
887 ttm_put_pages(&ttm->pages[i], 1,
888 ttm->page_flags,
889 ttm->caching_state);
890 }
891 }
892 ttm->state = tt_unpopulated;
893}
894EXPORT_SYMBOL(ttm_pool_unpopulate);
895
896int ttm_page_alloc_debugfs(struct seq_file *m, void *data)
897{
898 struct ttm_page_pool *p;
899 unsigned i;
900 char *h[] = {"pool", "refills", "pages freed", "size"};
901 if (!_manager) {
902 seq_printf(m, "No pool allocator running.\n");
903 return 0;
904 }
905 seq_printf(m, "%6s %12s %13s %8s\n",
906 h[0], h[1], h[2], h[3]);
907 for (i = 0; i < NUM_POOLS; ++i) {
908 p = &_manager->pools[i];
909
910 seq_printf(m, "%6s %12ld %13ld %8d\n",
911 p->name, p->nrefills,
912 p->nfrees, p->npages);
913 }
914 return 0;
915}
916EXPORT_SYMBOL(ttm_page_alloc_debugfs);