1// SPDX-License-Identifier: GPL-2.0 OR MIT
2/*
3 * Copyright 2020 Advanced Micro Devices, Inc.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions 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 NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21 * OTHER DEALINGS IN THE SOFTWARE.
22 *
23 * Authors: Christian König
24 */
25
26/* Pooling of allocated pages is necessary because changing the caching
27 * attributes on x86 of the linear mapping requires a costly cross CPU TLB
28 * invalidate for those addresses.
29 *
30 * Additional to that allocations from the DMA coherent API are pooled as well
31 * cause they are rather slow compared to alloc_pages+map.
32 */
33
34#include <linux/module.h>
35#include <linux/dma-mapping.h>
36#include <linux/debugfs.h>
37#include <linux/highmem.h>
38#include <linux/sched/mm.h>
39
40#ifdef CONFIG_X86
41#include <asm/set_memory.h>
42#endif
43
44#include <drm/ttm/ttm_pool.h>
45#include <drm/ttm/ttm_tt.h>
46#include <drm/ttm/ttm_bo.h>
47
48#include "ttm_module.h"
49
50/**
51 * struct ttm_pool_dma - Helper object for coherent DMA mappings
52 *
53 * @addr: original DMA address returned for the mapping
54 * @vaddr: original vaddr return for the mapping and order in the lower bits
55 */
56struct ttm_pool_dma {
57 dma_addr_t addr;
58 unsigned long vaddr;
59};
60
61static unsigned long page_pool_size;
62
63MODULE_PARM_DESC(page_pool_size, "Number of pages in the WC/UC/DMA pool");
64module_param(page_pool_size, ulong, 0644);
65
66static atomic_long_t allocated_pages;
67
68static struct ttm_pool_type global_write_combined[NR_PAGE_ORDERS];
69static struct ttm_pool_type global_uncached[NR_PAGE_ORDERS];
70
71static struct ttm_pool_type global_dma32_write_combined[NR_PAGE_ORDERS];
72static struct ttm_pool_type global_dma32_uncached[NR_PAGE_ORDERS];
73
74static spinlock_t shrinker_lock;
75static struct list_head shrinker_list;
76static struct shrinker *mm_shrinker;
77static DECLARE_RWSEM(pool_shrink_rwsem);
78
79/* Allocate pages of size 1 << order with the given gfp_flags */
80static struct page *ttm_pool_alloc_page(struct ttm_pool *pool, gfp_t gfp_flags,
81 unsigned int order)
82{
83 unsigned long attr = DMA_ATTR_FORCE_CONTIGUOUS;
84 struct ttm_pool_dma *dma;
85 struct page *p;
86 void *vaddr;
87
88 /* Don't set the __GFP_COMP flag for higher order allocations.
89 * Mapping pages directly into an userspace process and calling
90 * put_page() on a TTM allocated page is illegal.
91 */
92 if (order)
93 gfp_flags |= __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN |
94 __GFP_KSWAPD_RECLAIM;
95
96 if (!pool->use_dma_alloc) {
97 p = alloc_pages_node(nid: pool->nid, gfp_mask: gfp_flags, order);
98 if (p)
99 p->private = order;
100 return p;
101 }
102
103 dma = kmalloc(size: sizeof(*dma), GFP_KERNEL);
104 if (!dma)
105 return NULL;
106
107 if (order)
108 attr |= DMA_ATTR_NO_WARN;
109
110 vaddr = dma_alloc_attrs(dev: pool->dev, size: (1ULL << order) * PAGE_SIZE,
111 dma_handle: &dma->addr, flag: gfp_flags, attrs: attr);
112 if (!vaddr)
113 goto error_free;
114
115 /* TODO: This is an illegal abuse of the DMA API, but we need to rework
116 * TTM page fault handling and extend the DMA API to clean this up.
117 */
118 if (is_vmalloc_addr(x: vaddr))
119 p = vmalloc_to_page(addr: vaddr);
120 else
121 p = virt_to_page(vaddr);
122
123 dma->vaddr = (unsigned long)vaddr | order;
124 p->private = (unsigned long)dma;
125 return p;
126
127error_free:
128 kfree(objp: dma);
129 return NULL;
130}
131
132/* Reset the caching and pages of size 1 << order */
133static void ttm_pool_free_page(struct ttm_pool *pool, enum ttm_caching caching,
134 unsigned int order, struct page *p)
135{
136 unsigned long attr = DMA_ATTR_FORCE_CONTIGUOUS;
137 struct ttm_pool_dma *dma;
138 void *vaddr;
139
140#ifdef CONFIG_X86
141 /* We don't care that set_pages_wb is inefficient here. This is only
142 * used when we have to shrink and CPU overhead is irrelevant then.
143 */
144 if (caching != ttm_cached && !PageHighMem(page: p))
145 set_pages_wb(page: p, numpages: 1 << order);
146#endif
147
148 if (!pool || !pool->use_dma_alloc) {
149 __free_pages(page: p, order);
150 return;
151 }
152
153 if (order)
154 attr |= DMA_ATTR_NO_WARN;
155
156 dma = (void *)p->private;
157 vaddr = (void *)(dma->vaddr & PAGE_MASK);
158 dma_free_attrs(dev: pool->dev, size: (1UL << order) * PAGE_SIZE, cpu_addr: vaddr, dma_handle: dma->addr,
159 attrs: attr);
160 kfree(objp: dma);
161}
162
163/* Apply a new caching to an array of pages */
164static int ttm_pool_apply_caching(struct page **first, struct page **last,
165 enum ttm_caching caching)
166{
167#ifdef CONFIG_X86
168 unsigned int num_pages = last - first;
169
170 if (!num_pages)
171 return 0;
172
173 switch (caching) {
174 case ttm_cached:
175 break;
176 case ttm_write_combined:
177 return set_pages_array_wc(pages: first, addrinarray: num_pages);
178 case ttm_uncached:
179 return set_pages_array_uc(pages: first, addrinarray: num_pages);
180 }
181#endif
182 return 0;
183}
184
185/* Map pages of 1 << order size and fill the DMA address array */
186static int ttm_pool_map(struct ttm_pool *pool, unsigned int order,
187 struct page *p, dma_addr_t **dma_addr)
188{
189 dma_addr_t addr;
190 unsigned int i;
191
192 if (pool->use_dma_alloc) {
193 struct ttm_pool_dma *dma = (void *)p->private;
194
195 addr = dma->addr;
196 } else {
197 size_t size = (1ULL << order) * PAGE_SIZE;
198
199 addr = dma_map_page(pool->dev, p, 0, size, DMA_BIDIRECTIONAL);
200 if (dma_mapping_error(dev: pool->dev, dma_addr: addr))
201 return -EFAULT;
202 }
203
204 for (i = 1 << order; i ; --i) {
205 *(*dma_addr)++ = addr;
206 addr += PAGE_SIZE;
207 }
208
209 return 0;
210}
211
212/* Unmap pages of 1 << order size */
213static void ttm_pool_unmap(struct ttm_pool *pool, dma_addr_t dma_addr,
214 unsigned int num_pages)
215{
216 /* Unmapped while freeing the page */
217 if (pool->use_dma_alloc)
218 return;
219
220 dma_unmap_page(pool->dev, dma_addr, (long)num_pages << PAGE_SHIFT,
221 DMA_BIDIRECTIONAL);
222}
223
224/* Give pages into a specific pool_type */
225static void ttm_pool_type_give(struct ttm_pool_type *pt, struct page *p)
226{
227 unsigned int i, num_pages = 1 << pt->order;
228
229 for (i = 0; i < num_pages; ++i) {
230 if (PageHighMem(page: p))
231 clear_highpage(page: p + i);
232 else
233 clear_page(page_address(p + i));
234 }
235
236 spin_lock(lock: &pt->lock);
237 list_add(new: &p->lru, head: &pt->pages);
238 spin_unlock(lock: &pt->lock);
239 atomic_long_add(i: 1 << pt->order, v: &allocated_pages);
240}
241
242/* Take pages from a specific pool_type, return NULL when nothing available */
243static struct page *ttm_pool_type_take(struct ttm_pool_type *pt)
244{
245 struct page *p;
246
247 spin_lock(lock: &pt->lock);
248 p = list_first_entry_or_null(&pt->pages, typeof(*p), lru);
249 if (p) {
250 atomic_long_sub(i: 1 << pt->order, v: &allocated_pages);
251 list_del(entry: &p->lru);
252 }
253 spin_unlock(lock: &pt->lock);
254
255 return p;
256}
257
258/* Initialize and add a pool type to the global shrinker list */
259static void ttm_pool_type_init(struct ttm_pool_type *pt, struct ttm_pool *pool,
260 enum ttm_caching caching, unsigned int order)
261{
262 pt->pool = pool;
263 pt->caching = caching;
264 pt->order = order;
265 spin_lock_init(&pt->lock);
266 INIT_LIST_HEAD(list: &pt->pages);
267
268 spin_lock(lock: &shrinker_lock);
269 list_add_tail(new: &pt->shrinker_list, head: &shrinker_list);
270 spin_unlock(lock: &shrinker_lock);
271}
272
273/* Remove a pool_type from the global shrinker list and free all pages */
274static void ttm_pool_type_fini(struct ttm_pool_type *pt)
275{
276 struct page *p;
277
278 spin_lock(lock: &shrinker_lock);
279 list_del(entry: &pt->shrinker_list);
280 spin_unlock(lock: &shrinker_lock);
281
282 while ((p = ttm_pool_type_take(pt)))
283 ttm_pool_free_page(pool: pt->pool, caching: pt->caching, order: pt->order, p);
284}
285
286/* Return the pool_type to use for the given caching and order */
287static struct ttm_pool_type *ttm_pool_select_type(struct ttm_pool *pool,
288 enum ttm_caching caching,
289 unsigned int order)
290{
291 if (pool->use_dma_alloc)
292 return &pool->caching[caching].orders[order];
293
294#ifdef CONFIG_X86
295 switch (caching) {
296 case ttm_write_combined:
297 if (pool->nid != NUMA_NO_NODE)
298 return &pool->caching[caching].orders[order];
299
300 if (pool->use_dma32)
301 return &global_dma32_write_combined[order];
302
303 return &global_write_combined[order];
304 case ttm_uncached:
305 if (pool->nid != NUMA_NO_NODE)
306 return &pool->caching[caching].orders[order];
307
308 if (pool->use_dma32)
309 return &global_dma32_uncached[order];
310
311 return &global_uncached[order];
312 default:
313 break;
314 }
315#endif
316
317 return NULL;
318}
319
320/* Free pages using the global shrinker list */
321static unsigned int ttm_pool_shrink(void)
322{
323 struct ttm_pool_type *pt;
324 unsigned int num_pages;
325 struct page *p;
326
327 down_read(sem: &pool_shrink_rwsem);
328 spin_lock(lock: &shrinker_lock);
329 pt = list_first_entry(&shrinker_list, typeof(*pt), shrinker_list);
330 list_move_tail(list: &pt->shrinker_list, head: &shrinker_list);
331 spin_unlock(lock: &shrinker_lock);
332
333 p = ttm_pool_type_take(pt);
334 if (p) {
335 ttm_pool_free_page(pool: pt->pool, caching: pt->caching, order: pt->order, p);
336 num_pages = 1 << pt->order;
337 } else {
338 num_pages = 0;
339 }
340 up_read(sem: &pool_shrink_rwsem);
341
342 return num_pages;
343}
344
345/* Return the allocation order based for a page */
346static unsigned int ttm_pool_page_order(struct ttm_pool *pool, struct page *p)
347{
348 if (pool->use_dma_alloc) {
349 struct ttm_pool_dma *dma = (void *)p->private;
350
351 return dma->vaddr & ~PAGE_MASK;
352 }
353
354 return p->private;
355}
356
357/* Called when we got a page, either from a pool or newly allocated */
358static int ttm_pool_page_allocated(struct ttm_pool *pool, unsigned int order,
359 struct page *p, dma_addr_t **dma_addr,
360 unsigned long *num_pages,
361 struct page ***pages)
362{
363 unsigned int i;
364 int r;
365
366 if (*dma_addr) {
367 r = ttm_pool_map(pool, order, p, dma_addr);
368 if (r)
369 return r;
370 }
371
372 *num_pages -= 1 << order;
373 for (i = 1 << order; i; --i, ++(*pages), ++p)
374 **pages = p;
375
376 return 0;
377}
378
379/**
380 * ttm_pool_free_range() - Free a range of TTM pages
381 * @pool: The pool used for allocating.
382 * @tt: The struct ttm_tt holding the page pointers.
383 * @caching: The page caching mode used by the range.
384 * @start_page: index for first page to free.
385 * @end_page: index for last page to free + 1.
386 *
387 * During allocation the ttm_tt page-vector may be populated with ranges of
388 * pages with different attributes if allocation hit an error without being
389 * able to completely fulfill the allocation. This function can be used
390 * to free these individual ranges.
391 */
392static void ttm_pool_free_range(struct ttm_pool *pool, struct ttm_tt *tt,
393 enum ttm_caching caching,
394 pgoff_t start_page, pgoff_t end_page)
395{
396 struct page **pages = &tt->pages[start_page];
397 unsigned int order;
398 pgoff_t i, nr;
399
400 for (i = start_page; i < end_page; i += nr, pages += nr) {
401 struct ttm_pool_type *pt = NULL;
402
403 order = ttm_pool_page_order(pool, p: *pages);
404 nr = (1UL << order);
405 if (tt->dma_address)
406 ttm_pool_unmap(pool, dma_addr: tt->dma_address[i], num_pages: nr);
407
408 pt = ttm_pool_select_type(pool, caching, order);
409 if (pt)
410 ttm_pool_type_give(pt, p: *pages);
411 else
412 ttm_pool_free_page(pool, caching, order, p: *pages);
413 }
414}
415
416/**
417 * ttm_pool_alloc - Fill a ttm_tt object
418 *
419 * @pool: ttm_pool to use
420 * @tt: ttm_tt object to fill
421 * @ctx: operation context
422 *
423 * Fill the ttm_tt object with pages and also make sure to DMA map them when
424 * necessary.
425 *
426 * Returns: 0 on successe, negative error code otherwise.
427 */
428int ttm_pool_alloc(struct ttm_pool *pool, struct ttm_tt *tt,
429 struct ttm_operation_ctx *ctx)
430{
431 pgoff_t num_pages = tt->num_pages;
432 dma_addr_t *dma_addr = tt->dma_address;
433 struct page **caching = tt->pages;
434 struct page **pages = tt->pages;
435 enum ttm_caching page_caching;
436 gfp_t gfp_flags = GFP_USER;
437 pgoff_t caching_divide;
438 unsigned int order;
439 struct page *p;
440 int r;
441
442 WARN_ON(!num_pages || ttm_tt_is_populated(tt));
443 WARN_ON(dma_addr && !pool->dev);
444
445 if (tt->page_flags & TTM_TT_FLAG_ZERO_ALLOC)
446 gfp_flags |= __GFP_ZERO;
447
448 if (ctx->gfp_retry_mayfail)
449 gfp_flags |= __GFP_RETRY_MAYFAIL;
450
451 if (pool->use_dma32)
452 gfp_flags |= GFP_DMA32;
453 else
454 gfp_flags |= GFP_HIGHUSER;
455
456 for (order = min_t(unsigned int, MAX_PAGE_ORDER, __fls(num_pages));
457 num_pages;
458 order = min_t(unsigned int, order, __fls(num_pages))) {
459 struct ttm_pool_type *pt;
460
461 page_caching = tt->caching;
462 pt = ttm_pool_select_type(pool, caching: tt->caching, order);
463 p = pt ? ttm_pool_type_take(pt) : NULL;
464 if (p) {
465 r = ttm_pool_apply_caching(first: caching, last: pages,
466 caching: tt->caching);
467 if (r)
468 goto error_free_page;
469
470 caching = pages;
471 do {
472 r = ttm_pool_page_allocated(pool, order, p,
473 dma_addr: &dma_addr,
474 num_pages: &num_pages,
475 pages: &pages);
476 if (r)
477 goto error_free_page;
478
479 caching = pages;
480 if (num_pages < (1 << order))
481 break;
482
483 p = ttm_pool_type_take(pt);
484 } while (p);
485 }
486
487 page_caching = ttm_cached;
488 while (num_pages >= (1 << order) &&
489 (p = ttm_pool_alloc_page(pool, gfp_flags, order))) {
490
491 if (PageHighMem(page: p)) {
492 r = ttm_pool_apply_caching(first: caching, last: pages,
493 caching: tt->caching);
494 if (r)
495 goto error_free_page;
496 caching = pages;
497 }
498 r = ttm_pool_page_allocated(pool, order, p, dma_addr: &dma_addr,
499 num_pages: &num_pages, pages: &pages);
500 if (r)
501 goto error_free_page;
502 if (PageHighMem(page: p))
503 caching = pages;
504 }
505
506 if (!p) {
507 if (order) {
508 --order;
509 continue;
510 }
511 r = -ENOMEM;
512 goto error_free_all;
513 }
514 }
515
516 r = ttm_pool_apply_caching(first: caching, last: pages, caching: tt->caching);
517 if (r)
518 goto error_free_all;
519
520 return 0;
521
522error_free_page:
523 ttm_pool_free_page(pool, caching: page_caching, order, p);
524
525error_free_all:
526 num_pages = tt->num_pages - num_pages;
527 caching_divide = caching - tt->pages;
528 ttm_pool_free_range(pool, tt, caching: tt->caching, start_page: 0, end_page: caching_divide);
529 ttm_pool_free_range(pool, tt, caching: ttm_cached, start_page: caching_divide, end_page: num_pages);
530
531 return r;
532}
533EXPORT_SYMBOL(ttm_pool_alloc);
534
535/**
536 * ttm_pool_free - Free the backing pages from a ttm_tt object
537 *
538 * @pool: Pool to give pages back to.
539 * @tt: ttm_tt object to unpopulate
540 *
541 * Give the packing pages back to a pool or free them
542 */
543void ttm_pool_free(struct ttm_pool *pool, struct ttm_tt *tt)
544{
545 ttm_pool_free_range(pool, tt, caching: tt->caching, start_page: 0, end_page: tt->num_pages);
546
547 while (atomic_long_read(v: &allocated_pages) > page_pool_size)
548 ttm_pool_shrink();
549}
550EXPORT_SYMBOL(ttm_pool_free);
551
552/**
553 * ttm_pool_init - Initialize a pool
554 *
555 * @pool: the pool to initialize
556 * @dev: device for DMA allocations and mappings
557 * @nid: NUMA node to use for allocations
558 * @use_dma_alloc: true if coherent DMA alloc should be used
559 * @use_dma32: true if GFP_DMA32 should be used
560 *
561 * Initialize the pool and its pool types.
562 */
563void ttm_pool_init(struct ttm_pool *pool, struct device *dev,
564 int nid, bool use_dma_alloc, bool use_dma32)
565{
566 unsigned int i, j;
567
568 WARN_ON(!dev && use_dma_alloc);
569
570 pool->dev = dev;
571 pool->nid = nid;
572 pool->use_dma_alloc = use_dma_alloc;
573 pool->use_dma32 = use_dma32;
574
575 for (i = 0; i < TTM_NUM_CACHING_TYPES; ++i) {
576 for (j = 0; j < NR_PAGE_ORDERS; ++j) {
577 struct ttm_pool_type *pt;
578
579 /* Initialize only pool types which are actually used */
580 pt = ttm_pool_select_type(pool, caching: i, order: j);
581 if (pt != &pool->caching[i].orders[j])
582 continue;
583
584 ttm_pool_type_init(pt, pool, caching: i, order: j);
585 }
586 }
587}
588EXPORT_SYMBOL(ttm_pool_init);
589
590/**
591 * ttm_pool_synchronize_shrinkers - Wait for all running shrinkers to complete.
592 *
593 * This is useful to guarantee that all shrinker invocations have seen an
594 * update, before freeing memory, similar to rcu.
595 */
596static void ttm_pool_synchronize_shrinkers(void)
597{
598 down_write(sem: &pool_shrink_rwsem);
599 up_write(sem: &pool_shrink_rwsem);
600}
601
602/**
603 * ttm_pool_fini - Cleanup a pool
604 *
605 * @pool: the pool to clean up
606 *
607 * Free all pages in the pool and unregister the types from the global
608 * shrinker.
609 */
610void ttm_pool_fini(struct ttm_pool *pool)
611{
612 unsigned int i, j;
613
614 for (i = 0; i < TTM_NUM_CACHING_TYPES; ++i) {
615 for (j = 0; j < NR_PAGE_ORDERS; ++j) {
616 struct ttm_pool_type *pt;
617
618 pt = ttm_pool_select_type(pool, caching: i, order: j);
619 if (pt != &pool->caching[i].orders[j])
620 continue;
621
622 ttm_pool_type_fini(pt);
623 }
624 }
625
626 /* We removed the pool types from the LRU, but we need to also make sure
627 * that no shrinker is concurrently freeing pages from the pool.
628 */
629 ttm_pool_synchronize_shrinkers();
630}
631EXPORT_SYMBOL(ttm_pool_fini);
632
633/* As long as pages are available make sure to release at least one */
634static unsigned long ttm_pool_shrinker_scan(struct shrinker *shrink,
635 struct shrink_control *sc)
636{
637 unsigned long num_freed = 0;
638
639 do
640 num_freed += ttm_pool_shrink();
641 while (!num_freed && atomic_long_read(v: &allocated_pages));
642
643 return num_freed;
644}
645
646/* Return the number of pages available or SHRINK_EMPTY if we have none */
647static unsigned long ttm_pool_shrinker_count(struct shrinker *shrink,
648 struct shrink_control *sc)
649{
650 unsigned long num_pages = atomic_long_read(v: &allocated_pages);
651
652 return num_pages ? num_pages : SHRINK_EMPTY;
653}
654
655#ifdef CONFIG_DEBUG_FS
656/* Count the number of pages available in a pool_type */
657static unsigned int ttm_pool_type_count(struct ttm_pool_type *pt)
658{
659 unsigned int count = 0;
660 struct page *p;
661
662 spin_lock(lock: &pt->lock);
663 /* Only used for debugfs, the overhead doesn't matter */
664 list_for_each_entry(p, &pt->pages, lru)
665 ++count;
666 spin_unlock(lock: &pt->lock);
667
668 return count;
669}
670
671/* Print a nice header for the order */
672static void ttm_pool_debugfs_header(struct seq_file *m)
673{
674 unsigned int i;
675
676 seq_puts(m, s: "\t ");
677 for (i = 0; i < NR_PAGE_ORDERS; ++i)
678 seq_printf(m, fmt: " ---%2u---", i);
679 seq_puts(m, s: "\n");
680}
681
682/* Dump information about the different pool types */
683static void ttm_pool_debugfs_orders(struct ttm_pool_type *pt,
684 struct seq_file *m)
685{
686 unsigned int i;
687
688 for (i = 0; i < NR_PAGE_ORDERS; ++i)
689 seq_printf(m, fmt: " %8u", ttm_pool_type_count(pt: &pt[i]));
690 seq_puts(m, s: "\n");
691}
692
693/* Dump the total amount of allocated pages */
694static void ttm_pool_debugfs_footer(struct seq_file *m)
695{
696 seq_printf(m, fmt: "\ntotal\t: %8lu of %8lu\n",
697 atomic_long_read(v: &allocated_pages), page_pool_size);
698}
699
700/* Dump the information for the global pools */
701static int ttm_pool_debugfs_globals_show(struct seq_file *m, void *data)
702{
703 ttm_pool_debugfs_header(m);
704
705 spin_lock(lock: &shrinker_lock);
706 seq_puts(m, s: "wc\t:");
707 ttm_pool_debugfs_orders(pt: global_write_combined, m);
708 seq_puts(m, s: "uc\t:");
709 ttm_pool_debugfs_orders(pt: global_uncached, m);
710 seq_puts(m, s: "wc 32\t:");
711 ttm_pool_debugfs_orders(pt: global_dma32_write_combined, m);
712 seq_puts(m, s: "uc 32\t:");
713 ttm_pool_debugfs_orders(pt: global_dma32_uncached, m);
714 spin_unlock(lock: &shrinker_lock);
715
716 ttm_pool_debugfs_footer(m);
717
718 return 0;
719}
720DEFINE_SHOW_ATTRIBUTE(ttm_pool_debugfs_globals);
721
722/**
723 * ttm_pool_debugfs - Debugfs dump function for a pool
724 *
725 * @pool: the pool to dump the information for
726 * @m: seq_file to dump to
727 *
728 * Make a debugfs dump with the per pool and global information.
729 */
730int ttm_pool_debugfs(struct ttm_pool *pool, struct seq_file *m)
731{
732 unsigned int i;
733
734 if (!pool->use_dma_alloc) {
735 seq_puts(m, s: "unused\n");
736 return 0;
737 }
738
739 ttm_pool_debugfs_header(m);
740
741 spin_lock(lock: &shrinker_lock);
742 for (i = 0; i < TTM_NUM_CACHING_TYPES; ++i) {
743 seq_puts(m, s: "DMA ");
744 switch (i) {
745 case ttm_cached:
746 seq_puts(m, s: "\t:");
747 break;
748 case ttm_write_combined:
749 seq_puts(m, s: "wc\t:");
750 break;
751 case ttm_uncached:
752 seq_puts(m, s: "uc\t:");
753 break;
754 }
755 ttm_pool_debugfs_orders(pt: pool->caching[i].orders, m);
756 }
757 spin_unlock(lock: &shrinker_lock);
758
759 ttm_pool_debugfs_footer(m);
760 return 0;
761}
762EXPORT_SYMBOL(ttm_pool_debugfs);
763
764/* Test the shrinker functions and dump the result */
765static int ttm_pool_debugfs_shrink_show(struct seq_file *m, void *data)
766{
767 struct shrink_control sc = { .gfp_mask = GFP_NOFS };
768
769 fs_reclaim_acquire(GFP_KERNEL);
770 seq_printf(m, fmt: "%lu/%lu\n", ttm_pool_shrinker_count(shrink: mm_shrinker, sc: &sc),
771 ttm_pool_shrinker_scan(shrink: mm_shrinker, sc: &sc));
772 fs_reclaim_release(GFP_KERNEL);
773
774 return 0;
775}
776DEFINE_SHOW_ATTRIBUTE(ttm_pool_debugfs_shrink);
777
778#endif
779
780/**
781 * ttm_pool_mgr_init - Initialize globals
782 *
783 * @num_pages: default number of pages
784 *
785 * Initialize the global locks and lists for the MM shrinker.
786 */
787int ttm_pool_mgr_init(unsigned long num_pages)
788{
789 unsigned int i;
790
791 if (!page_pool_size)
792 page_pool_size = num_pages;
793
794 spin_lock_init(&shrinker_lock);
795 INIT_LIST_HEAD(list: &shrinker_list);
796
797 for (i = 0; i < NR_PAGE_ORDERS; ++i) {
798 ttm_pool_type_init(pt: &global_write_combined[i], NULL,
799 caching: ttm_write_combined, order: i);
800 ttm_pool_type_init(pt: &global_uncached[i], NULL, caching: ttm_uncached, order: i);
801
802 ttm_pool_type_init(pt: &global_dma32_write_combined[i], NULL,
803 caching: ttm_write_combined, order: i);
804 ttm_pool_type_init(pt: &global_dma32_uncached[i], NULL,
805 caching: ttm_uncached, order: i);
806 }
807
808#ifdef CONFIG_DEBUG_FS
809 debugfs_create_file(name: "page_pool", mode: 0444, parent: ttm_debugfs_root, NULL,
810 fops: &ttm_pool_debugfs_globals_fops);
811 debugfs_create_file(name: "page_pool_shrink", mode: 0400, parent: ttm_debugfs_root, NULL,
812 fops: &ttm_pool_debugfs_shrink_fops);
813#endif
814
815 mm_shrinker = shrinker_alloc(flags: 0, fmt: "drm-ttm_pool");
816 if (!mm_shrinker)
817 return -ENOMEM;
818
819 mm_shrinker->count_objects = ttm_pool_shrinker_count;
820 mm_shrinker->scan_objects = ttm_pool_shrinker_scan;
821 mm_shrinker->seeks = 1;
822
823 shrinker_register(shrinker: mm_shrinker);
824
825 return 0;
826}
827
828/**
829 * ttm_pool_mgr_fini - Finalize globals
830 *
831 * Cleanup the global pools and unregister the MM shrinker.
832 */
833void ttm_pool_mgr_fini(void)
834{
835 unsigned int i;
836
837 for (i = 0; i < NR_PAGE_ORDERS; ++i) {
838 ttm_pool_type_fini(pt: &global_write_combined[i]);
839 ttm_pool_type_fini(pt: &global_uncached[i]);
840
841 ttm_pool_type_fini(pt: &global_dma32_write_combined[i]);
842 ttm_pool_type_fini(pt: &global_dma32_uncached[i]);
843 }
844
845 shrinker_free(shrinker: mm_shrinker);
846 WARN_ON(!list_empty(&shrinker_list));
847}
848

source code of linux/drivers/gpu/drm/ttm/ttm_pool.c