1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
2 /**************************************************************************
4 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the
9 * "Software"), to deal in the Software without restriction, including
10 * without limitation the rights to use, copy, modify, merge, publish,
11 * distribute, sub license, and/or sell copies of the Software, and to
12 * permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
15 * The above copyright notice and this permission notice (including the
16 * next paragraph) shall be included in all copies or substantial portions
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
22 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
23 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
25 * USE OR OTHER DEALINGS IN THE SOFTWARE.
27 **************************************************************************/
29 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
32 #define pr_fmt(fmt) "[TTM] " fmt
34 #include <linux/sched.h>
35 #include <linux/pagemap.h>
36 #include <linux/shmem_fs.h>
37 #include <linux/file.h>
38 #include <drm/drm_cache.h>
39 #include <drm/ttm/ttm_bo_driver.h>
41 #include "ttm_module.h"
43 static unsigned long ttm_pages_limit;
45 MODULE_PARM_DESC(pages_limit, "Limit for the allocated pages");
46 module_param_named(pages_limit, ttm_pages_limit, ulong, 0644);
48 static unsigned long ttm_dma32_pages_limit;
50 MODULE_PARM_DESC(dma32_pages_limit, "Limit for the allocated DMA32 pages");
51 module_param_named(dma32_pages_limit, ttm_dma32_pages_limit, ulong, 0644);
53 static atomic_long_t ttm_pages_allocated;
54 static atomic_long_t ttm_dma32_pages_allocated;
57 * Allocates a ttm structure for the given BO.
59 int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)
61 struct ttm_device *bdev = bo->bdev;
62 uint32_t page_flags = 0;
64 dma_resv_assert_held(bo->base.resv);
70 case ttm_bo_type_device:
72 page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC;
74 case ttm_bo_type_kernel:
77 page_flags |= TTM_PAGE_FLAG_SG;
80 pr_err("Illegal buffer object type\n");
84 bo->ttm = bdev->funcs->ttm_tt_create(bo, page_flags);
85 if (unlikely(bo->ttm == NULL))
92 * Allocates storage for pointers to the pages that back the ttm.
94 static int ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
96 ttm->pages = kvmalloc_array(ttm->num_pages, sizeof(void*),
97 GFP_KERNEL | __GFP_ZERO);
103 static int ttm_dma_tt_alloc_page_directory(struct ttm_tt *ttm)
105 ttm->pages = kvmalloc_array(ttm->num_pages,
106 sizeof(*ttm->pages) +
107 sizeof(*ttm->dma_address),
108 GFP_KERNEL | __GFP_ZERO);
112 ttm->dma_address = (void *)(ttm->pages + ttm->num_pages);
116 static int ttm_sg_tt_alloc_page_directory(struct ttm_tt *ttm)
118 ttm->dma_address = kvmalloc_array(ttm->num_pages,
119 sizeof(*ttm->dma_address),
120 GFP_KERNEL | __GFP_ZERO);
121 if (!ttm->dma_address)
126 void ttm_tt_destroy_common(struct ttm_device *bdev, struct ttm_tt *ttm)
128 ttm_tt_unpopulate(bdev, ttm);
130 if (ttm->swap_storage)
131 fput(ttm->swap_storage);
133 ttm->swap_storage = NULL;
135 EXPORT_SYMBOL(ttm_tt_destroy_common);
137 void ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm)
139 bdev->funcs->ttm_tt_destroy(bdev, ttm);
142 static void ttm_tt_init_fields(struct ttm_tt *ttm,
143 struct ttm_buffer_object *bo,
145 enum ttm_caching caching)
147 ttm->num_pages = PAGE_ALIGN(bo->base.size) >> PAGE_SHIFT;
148 ttm->caching = ttm_cached;
149 ttm->page_flags = page_flags;
150 ttm->dma_address = NULL;
151 ttm->swap_storage = NULL;
153 ttm->caching = caching;
156 int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
157 uint32_t page_flags, enum ttm_caching caching)
159 ttm_tt_init_fields(ttm, bo, page_flags, caching);
161 if (ttm_tt_alloc_page_directory(ttm)) {
162 pr_err("Failed allocating page table\n");
167 EXPORT_SYMBOL(ttm_tt_init);
169 void ttm_tt_fini(struct ttm_tt *ttm)
174 kvfree(ttm->dma_address);
176 ttm->dma_address = NULL;
178 EXPORT_SYMBOL(ttm_tt_fini);
180 int ttm_sg_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
181 uint32_t page_flags, enum ttm_caching caching)
185 ttm_tt_init_fields(ttm, bo, page_flags, caching);
187 if (page_flags & TTM_PAGE_FLAG_SG)
188 ret = ttm_sg_tt_alloc_page_directory(ttm);
190 ret = ttm_dma_tt_alloc_page_directory(ttm);
192 pr_err("Failed allocating page table\n");
197 EXPORT_SYMBOL(ttm_sg_tt_init);
199 int ttm_tt_swapin(struct ttm_tt *ttm)
201 struct address_space *swap_space;
202 struct file *swap_storage;
203 struct page *from_page;
204 struct page *to_page;
208 swap_storage = ttm->swap_storage;
209 BUG_ON(swap_storage == NULL);
211 swap_space = swap_storage->f_mapping;
212 gfp_mask = mapping_gfp_mask(swap_space);
214 for (i = 0; i < ttm->num_pages; ++i) {
215 from_page = shmem_read_mapping_page_gfp(swap_space, i,
217 if (IS_ERR(from_page)) {
218 ret = PTR_ERR(from_page);
221 to_page = ttm->pages[i];
222 if (unlikely(to_page == NULL)) {
227 copy_highpage(to_page, from_page);
232 ttm->swap_storage = NULL;
233 ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
242 * ttm_tt_swapout - swap out tt object
244 * @bdev: TTM device structure.
245 * @ttm: The struct ttm_tt.
246 * @gfp_flags: Flags to use for memory allocation.
248 * Swapout a TT object to a shmem_file, return number of pages swapped out or
249 * negative error code.
251 int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm,
254 loff_t size = (loff_t)ttm->num_pages << PAGE_SHIFT;
255 struct address_space *swap_space;
256 struct file *swap_storage;
257 struct page *from_page;
258 struct page *to_page;
261 swap_storage = shmem_file_setup("ttm swap", size, 0);
262 if (IS_ERR(swap_storage)) {
263 pr_err("Failed allocating swap storage\n");
264 return PTR_ERR(swap_storage);
267 swap_space = swap_storage->f_mapping;
268 gfp_flags &= mapping_gfp_mask(swap_space);
270 for (i = 0; i < ttm->num_pages; ++i) {
271 from_page = ttm->pages[i];
272 if (unlikely(from_page == NULL))
275 to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_flags);
276 if (IS_ERR(to_page)) {
277 ret = PTR_ERR(to_page);
280 copy_highpage(to_page, from_page);
281 set_page_dirty(to_page);
282 mark_page_accessed(to_page);
286 ttm_tt_unpopulate(bdev, ttm);
287 ttm->swap_storage = swap_storage;
288 ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
290 return ttm->num_pages;
298 static void ttm_tt_add_mapping(struct ttm_device *bdev, struct ttm_tt *ttm)
302 if (ttm->page_flags & TTM_PAGE_FLAG_SG)
305 for (i = 0; i < ttm->num_pages; ++i)
306 ttm->pages[i]->mapping = bdev->dev_mapping;
309 int ttm_tt_populate(struct ttm_device *bdev,
310 struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
317 if (ttm_tt_is_populated(ttm))
320 if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
321 atomic_long_add(ttm->num_pages, &ttm_pages_allocated);
322 if (bdev->pool.use_dma32)
323 atomic_long_add(ttm->num_pages,
324 &ttm_dma32_pages_allocated);
327 while (atomic_long_read(&ttm_pages_allocated) > ttm_pages_limit ||
328 atomic_long_read(&ttm_dma32_pages_allocated) >
329 ttm_dma32_pages_limit) {
331 ret = ttm_global_swapout(ctx, GFP_KERNEL);
338 if (bdev->funcs->ttm_tt_populate)
339 ret = bdev->funcs->ttm_tt_populate(bdev, ttm, ctx);
341 ret = ttm_pool_alloc(&bdev->pool, ttm, ctx);
345 ttm_tt_add_mapping(bdev, ttm);
346 ttm->page_flags |= TTM_PAGE_FLAG_PRIV_POPULATED;
347 if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
348 ret = ttm_tt_swapin(ttm);
349 if (unlikely(ret != 0)) {
350 ttm_tt_unpopulate(bdev, ttm);
358 if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
359 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);
360 if (bdev->pool.use_dma32)
361 atomic_long_sub(ttm->num_pages,
362 &ttm_dma32_pages_allocated);
366 EXPORT_SYMBOL(ttm_tt_populate);
368 static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
371 struct page **page = ttm->pages;
373 if (ttm->page_flags & TTM_PAGE_FLAG_SG)
376 for (i = 0; i < ttm->num_pages; ++i) {
377 (*page)->mapping = NULL;
378 (*page++)->index = 0;
382 void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)
384 if (!ttm_tt_is_populated(ttm))
387 ttm_tt_clear_mapping(ttm);
388 if (bdev->funcs->ttm_tt_unpopulate)
389 bdev->funcs->ttm_tt_unpopulate(bdev, ttm);
391 ttm_pool_free(&bdev->pool, ttm);
393 if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
394 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);
395 if (bdev->pool.use_dma32)
396 atomic_long_sub(ttm->num_pages,
397 &ttm_dma32_pages_allocated);
400 ttm->page_flags &= ~TTM_PAGE_FLAG_PRIV_POPULATED;
403 #ifdef CONFIG_DEBUG_FS
405 /* Test the shrinker functions and dump the result */
406 static int ttm_tt_debugfs_shrink_show(struct seq_file *m, void *data)
408 struct ttm_operation_ctx ctx = { false, false };
410 seq_printf(m, "%d\n", ttm_global_swapout(&ctx, GFP_KERNEL));
413 DEFINE_SHOW_ATTRIBUTE(ttm_tt_debugfs_shrink);
419 * ttm_tt_mgr_init - register with the MM shrinker
421 * Register with the MM shrinker for swapping out BOs.
423 void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages)
425 #ifdef CONFIG_DEBUG_FS
426 debugfs_create_file("tt_shrink", 0400, ttm_debugfs_root, NULL,
427 &ttm_tt_debugfs_shrink_fops);
430 if (!ttm_pages_limit)
431 ttm_pages_limit = num_pages;
433 if (!ttm_dma32_pages_limit)
434 ttm_dma32_pages_limit = num_dma32_pages;
437 static void ttm_kmap_iter_tt_map_local(struct ttm_kmap_iter *iter,
438 struct dma_buf_map *dmap,
441 struct ttm_kmap_iter_tt *iter_tt =
442 container_of(iter, typeof(*iter_tt), base);
444 dma_buf_map_set_vaddr(dmap, kmap_local_page_prot(iter_tt->tt->pages[i],
448 static void ttm_kmap_iter_tt_unmap_local(struct ttm_kmap_iter *iter,
449 struct dma_buf_map *map)
451 kunmap_local(map->vaddr);
454 static const struct ttm_kmap_iter_ops ttm_kmap_iter_tt_ops = {
455 .map_local = ttm_kmap_iter_tt_map_local,
456 .unmap_local = ttm_kmap_iter_tt_unmap_local,
461 * ttm_kmap_iter_tt_init - Initialize a struct ttm_kmap_iter_tt
462 * @iter_tt: The struct ttm_kmap_iter_tt to initialize.
463 * @tt: Struct ttm_tt holding page pointers of the struct ttm_resource.
465 * Return: Pointer to the embedded struct ttm_kmap_iter.
467 struct ttm_kmap_iter *
468 ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt,
471 iter_tt->base.ops = &ttm_kmap_iter_tt_ops;
474 iter_tt->prot = ttm_prot_from_caching(tt->caching, PAGE_KERNEL);
476 iter_tt->prot = PAGE_KERNEL;
478 return &iter_tt->base;
480 EXPORT_SYMBOL(ttm_kmap_iter_tt_init);