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1/* SPDX-License-Identifier: GPL-2.0 OR MIT */2/**************************************************************************3 *4 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA5 * All Rights Reserved.6 *7 * Permission is hereby granted, free of charge, to any person obtaining a8 * copy of this software and associated documentation files (the9 * "Software"), to deal in the Software without restriction, including10 * without limitation the rights to use, copy, modify, merge, publish,11 * distribute, sub license, and/or sell copies of the Software, and to12 * permit persons to whom the Software is furnished to do so, subject to13 * the following conditions:14 *15 * The above copyright notice and this permission notice (including the16 * next paragraph) shall be included in all copies or substantial portions17 * of the Software.18 *19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,21 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL22 * 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 OR24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE25 * USE OR OTHER DEALINGS IN THE SOFTWARE.26 *27 **************************************************************************/28/*29 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>30 */31 32#define pr_fmt(fmt) "[TTM] " fmt33 34#include <linux/cc_platform.h>35#include <linux/debugfs.h>36#include <linux/file.h>37#include <linux/module.h>38#include <linux/sched.h>39#include <linux/shmem_fs.h>40#include <drm/drm_cache.h>41#include <drm/drm_device.h>42#include <drm/drm_util.h>43#include <drm/ttm/ttm_bo.h>44#include <drm/ttm/ttm_tt.h>45 46#include "ttm_module.h"47 48static unsigned long ttm_pages_limit;49 50MODULE_PARM_DESC(pages_limit, "Limit for the allocated pages");51module_param_named(pages_limit, ttm_pages_limit, ulong, 0644);52 53static unsigned long ttm_dma32_pages_limit;54 55MODULE_PARM_DESC(dma32_pages_limit, "Limit for the allocated DMA32 pages");56module_param_named(dma32_pages_limit, ttm_dma32_pages_limit, ulong, 0644);57 58static atomic_long_t ttm_pages_allocated;59static atomic_long_t ttm_dma32_pages_allocated;60 61/*62 * Allocates a ttm structure for the given BO.63 */64int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)65{66 struct ttm_device *bdev = bo->bdev;67 struct drm_device *ddev = bo->base.dev;68 uint32_t page_flags = 0;69 70 dma_resv_assert_held(bo->base.resv);71 72 if (bo->ttm)73 return 0;74 75 switch (bo->type) {76 case ttm_bo_type_device:77 if (zero_alloc)78 page_flags |= TTM_TT_FLAG_ZERO_ALLOC;79 break;80 case ttm_bo_type_kernel:81 break;82 case ttm_bo_type_sg:83 page_flags |= TTM_TT_FLAG_EXTERNAL;84 break;85 default:86 pr_err("Illegal buffer object type\n");87 return -EINVAL;88 }89 /*90 * When using dma_alloc_coherent with memory encryption the91 * mapped TT pages need to be decrypted or otherwise the drivers92 * will end up sending encrypted mem to the gpu.93 */94 if (bdev->pool.use_dma_alloc && cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) {95 page_flags |= TTM_TT_FLAG_DECRYPTED;96 drm_info_once(ddev, "TT memory decryption enabled.");97 }98 99 bo->ttm = bdev->funcs->ttm_tt_create(bo, page_flags);100 if (unlikely(bo->ttm == NULL))101 return -ENOMEM;102 103 WARN_ON(bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE &&104 !(bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL));105 106 return 0;107}108EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_create);109 110/*111 * Allocates storage for pointers to the pages that back the ttm.112 */113static int ttm_tt_alloc_page_directory(struct ttm_tt *ttm)114{115 ttm->pages = kvcalloc(ttm->num_pages, sizeof(void*), GFP_KERNEL);116 if (!ttm->pages)117 return -ENOMEM;118 119 return 0;120}121 122static int ttm_dma_tt_alloc_page_directory(struct ttm_tt *ttm)123{124 ttm->pages = kvcalloc(ttm->num_pages, sizeof(*ttm->pages) +125 sizeof(*ttm->dma_address), GFP_KERNEL);126 if (!ttm->pages)127 return -ENOMEM;128 129 ttm->dma_address = (void *)(ttm->pages + ttm->num_pages);130 return 0;131}132 133static int ttm_sg_tt_alloc_page_directory(struct ttm_tt *ttm)134{135 ttm->dma_address = kvcalloc(ttm->num_pages, sizeof(*ttm->dma_address),136 GFP_KERNEL);137 if (!ttm->dma_address)138 return -ENOMEM;139 140 return 0;141}142 143void ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm)144{145 bdev->funcs->ttm_tt_destroy(bdev, ttm);146}147EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_destroy);148 149static void ttm_tt_init_fields(struct ttm_tt *ttm,150 struct ttm_buffer_object *bo,151 uint32_t page_flags,152 enum ttm_caching caching,153 unsigned long extra_pages)154{155 ttm->num_pages = (PAGE_ALIGN(bo->base.size) >> PAGE_SHIFT) + extra_pages;156 ttm->page_flags = page_flags;157 ttm->dma_address = NULL;158 ttm->swap_storage = NULL;159 ttm->sg = bo->sg;160 ttm->caching = caching;161}162 163int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,164 uint32_t page_flags, enum ttm_caching caching,165 unsigned long extra_pages)166{167 ttm_tt_init_fields(ttm, bo, page_flags, caching, extra_pages);168 169 if (ttm_tt_alloc_page_directory(ttm)) {170 pr_err("Failed allocating page table\n");171 return -ENOMEM;172 }173 return 0;174}175EXPORT_SYMBOL(ttm_tt_init);176 177void ttm_tt_fini(struct ttm_tt *ttm)178{179 WARN_ON(ttm->page_flags & TTM_TT_FLAG_PRIV_POPULATED);180 181 if (ttm->swap_storage)182 fput(ttm->swap_storage);183 ttm->swap_storage = NULL;184 185 if (ttm->pages)186 kvfree(ttm->pages);187 else188 kvfree(ttm->dma_address);189 ttm->pages = NULL;190 ttm->dma_address = NULL;191}192EXPORT_SYMBOL(ttm_tt_fini);193 194int ttm_sg_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,195 uint32_t page_flags, enum ttm_caching caching)196{197 int ret;198 199 ttm_tt_init_fields(ttm, bo, page_flags, caching, 0);200 201 if (page_flags & TTM_TT_FLAG_EXTERNAL)202 ret = ttm_sg_tt_alloc_page_directory(ttm);203 else204 ret = ttm_dma_tt_alloc_page_directory(ttm);205 if (ret) {206 pr_err("Failed allocating page table\n");207 return -ENOMEM;208 }209 return 0;210}211EXPORT_SYMBOL(ttm_sg_tt_init);212 213int ttm_tt_swapin(struct ttm_tt *ttm)214{215 struct address_space *swap_space;216 struct file *swap_storage;217 struct page *from_page;218 struct page *to_page;219 gfp_t gfp_mask;220 int i, ret;221 222 swap_storage = ttm->swap_storage;223 BUG_ON(swap_storage == NULL);224 225 swap_space = swap_storage->f_mapping;226 gfp_mask = mapping_gfp_mask(swap_space);227 228 for (i = 0; i < ttm->num_pages; ++i) {229 from_page = shmem_read_mapping_page_gfp(swap_space, i,230 gfp_mask);231 if (IS_ERR(from_page)) {232 ret = PTR_ERR(from_page);233 goto out_err;234 }235 to_page = ttm->pages[i];236 if (unlikely(to_page == NULL)) {237 ret = -ENOMEM;238 goto out_err;239 }240 241 copy_highpage(to_page, from_page);242 put_page(from_page);243 }244 245 fput(swap_storage);246 ttm->swap_storage = NULL;247 ttm->page_flags &= ~TTM_TT_FLAG_SWAPPED;248 249 return 0;250 251out_err:252 return ret;253}254EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_swapin);255 256/**257 * ttm_tt_swapout - swap out tt object258 *259 * @bdev: TTM device structure.260 * @ttm: The struct ttm_tt.261 * @gfp_flags: Flags to use for memory allocation.262 *263 * Swapout a TT object to a shmem_file, return number of pages swapped out or264 * negative error code.265 */266int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm,267 gfp_t gfp_flags)268{269 loff_t size = (loff_t)ttm->num_pages << PAGE_SHIFT;270 struct address_space *swap_space;271 struct file *swap_storage;272 struct page *from_page;273 struct page *to_page;274 int i, ret;275 276 swap_storage = shmem_file_setup("ttm swap", size, 0);277 if (IS_ERR(swap_storage)) {278 pr_err("Failed allocating swap storage\n");279 return PTR_ERR(swap_storage);280 }281 282 swap_space = swap_storage->f_mapping;283 gfp_flags &= mapping_gfp_mask(swap_space);284 285 for (i = 0; i < ttm->num_pages; ++i) {286 from_page = ttm->pages[i];287 if (unlikely(from_page == NULL))288 continue;289 290 to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_flags);291 if (IS_ERR(to_page)) {292 ret = PTR_ERR(to_page);293 goto out_err;294 }295 copy_highpage(to_page, from_page);296 set_page_dirty(to_page);297 mark_page_accessed(to_page);298 put_page(to_page);299 }300 301 ttm_tt_unpopulate(bdev, ttm);302 ttm->swap_storage = swap_storage;303 ttm->page_flags |= TTM_TT_FLAG_SWAPPED;304 305 return ttm->num_pages;306 307out_err:308 fput(swap_storage);309 310 return ret;311}312EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_swapout);313 314int ttm_tt_populate(struct ttm_device *bdev,315 struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)316{317 int ret;318 319 if (!ttm)320 return -EINVAL;321 322 if (ttm_tt_is_populated(ttm))323 return 0;324 325 if (!(ttm->page_flags & TTM_TT_FLAG_EXTERNAL)) {326 atomic_long_add(ttm->num_pages, &ttm_pages_allocated);327 if (bdev->pool.use_dma32)328 atomic_long_add(ttm->num_pages,329 &ttm_dma32_pages_allocated);330 }331 332 while (atomic_long_read(&ttm_pages_allocated) > ttm_pages_limit ||333 atomic_long_read(&ttm_dma32_pages_allocated) >334 ttm_dma32_pages_limit) {335 336 ret = ttm_global_swapout(ctx, GFP_KERNEL);337 if (ret == 0)338 break;339 if (ret < 0)340 goto error;341 }342 343 if (bdev->funcs->ttm_tt_populate)344 ret = bdev->funcs->ttm_tt_populate(bdev, ttm, ctx);345 else346 ret = ttm_pool_alloc(&bdev->pool, ttm, ctx);347 if (ret)348 goto error;349 350 ttm->page_flags |= TTM_TT_FLAG_PRIV_POPULATED;351 if (unlikely(ttm->page_flags & TTM_TT_FLAG_SWAPPED)) {352 ret = ttm_tt_swapin(ttm);353 if (unlikely(ret != 0)) {354 ttm_tt_unpopulate(bdev, ttm);355 return ret;356 }357 }358 359 return 0;360 361error:362 if (!(ttm->page_flags & TTM_TT_FLAG_EXTERNAL)) {363 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);364 if (bdev->pool.use_dma32)365 atomic_long_sub(ttm->num_pages,366 &ttm_dma32_pages_allocated);367 }368 return ret;369}370EXPORT_SYMBOL(ttm_tt_populate);371 372void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)373{374 if (!ttm_tt_is_populated(ttm))375 return;376 377 if (bdev->funcs->ttm_tt_unpopulate)378 bdev->funcs->ttm_tt_unpopulate(bdev, ttm);379 else380 ttm_pool_free(&bdev->pool, ttm);381 382 if (!(ttm->page_flags & TTM_TT_FLAG_EXTERNAL)) {383 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);384 if (bdev->pool.use_dma32)385 atomic_long_sub(ttm->num_pages,386 &ttm_dma32_pages_allocated);387 }388 389 ttm->page_flags &= ~TTM_TT_FLAG_PRIV_POPULATED;390}391EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_unpopulate);392 393#ifdef CONFIG_DEBUG_FS394 395/* Test the shrinker functions and dump the result */396static int ttm_tt_debugfs_shrink_show(struct seq_file *m, void *data)397{398 struct ttm_operation_ctx ctx = { false, false };399 400 seq_printf(m, "%d\n", ttm_global_swapout(&ctx, GFP_KERNEL));401 return 0;402}403DEFINE_SHOW_ATTRIBUTE(ttm_tt_debugfs_shrink);404 405#endif406 407 408/*409 * ttm_tt_mgr_init - register with the MM shrinker410 *411 * Register with the MM shrinker for swapping out BOs.412 */413void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages)414{415#ifdef CONFIG_DEBUG_FS416 debugfs_create_file("tt_shrink", 0400, ttm_debugfs_root, NULL,417 &ttm_tt_debugfs_shrink_fops);418#endif419 420 if (!ttm_pages_limit)421 ttm_pages_limit = num_pages;422 423 if (!ttm_dma32_pages_limit)424 ttm_dma32_pages_limit = num_dma32_pages;425}426 427static void ttm_kmap_iter_tt_map_local(struct ttm_kmap_iter *iter,428 struct iosys_map *dmap,429 pgoff_t i)430{431 struct ttm_kmap_iter_tt *iter_tt =432 container_of(iter, typeof(*iter_tt), base);433 434 iosys_map_set_vaddr(dmap, kmap_local_page_prot(iter_tt->tt->pages[i],435 iter_tt->prot));436}437 438static void ttm_kmap_iter_tt_unmap_local(struct ttm_kmap_iter *iter,439 struct iosys_map *map)440{441 kunmap_local(map->vaddr);442}443 444static const struct ttm_kmap_iter_ops ttm_kmap_iter_tt_ops = {445 .map_local = ttm_kmap_iter_tt_map_local,446 .unmap_local = ttm_kmap_iter_tt_unmap_local,447 .maps_tt = true,448};449 450/**451 * ttm_kmap_iter_tt_init - Initialize a struct ttm_kmap_iter_tt452 * @iter_tt: The struct ttm_kmap_iter_tt to initialize.453 * @tt: Struct ttm_tt holding page pointers of the struct ttm_resource.454 *455 * Return: Pointer to the embedded struct ttm_kmap_iter.456 */457struct ttm_kmap_iter *458ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt,459 struct ttm_tt *tt)460{461 iter_tt->base.ops = &ttm_kmap_iter_tt_ops;462 iter_tt->tt = tt;463 if (tt)464 iter_tt->prot = ttm_prot_from_caching(tt->caching, PAGE_KERNEL);465 else466 iter_tt->prot = PAGE_KERNEL;467 468 return &iter_tt->base;469}470EXPORT_SYMBOL(ttm_kmap_iter_tt_init);471 472unsigned long ttm_tt_pages_limit(void)473{474 return ttm_pages_limit;475}476EXPORT_SYMBOL(ttm_tt_pages_limit);477