drivers/gpu/drm/ttm/ttm_tt.c

   1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
   2 /**************************************************************************
   3  *
   4  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
   5  * All Rights Reserved.
   6  *
   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:
  14  *
  15  * The above copyright notice and this permission notice (including the
  16  * next paragraph) shall be included in all copies or substantial portions
  17  * of the Software.
  18  *
  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.
  26  *
  27  **************************************************************************/
  28 /*
  29  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
  30  */
  31
  32 #define pr_fmt(fmt) "[TTM] " fmt
  33
  34 #include <linux/sched.h>
  35 #include <linux/shmem_fs.h>
  36 #include <linux/file.h>
  37 #include <drm/drm_cache.h>
  38 #include <drm/ttm/ttm_bo_driver.h>
  39
  40 #include "ttm_module.h"
  41
  42 static unsigned long ttm_pages_limit;
  43
  44 MODULE_PARM_DESC(pages_limit, "Limit for the allocated pages");
  45 module_param_named(pages_limit, ttm_pages_limit, ulong, 0644);
  46
  47 static unsigned long ttm_dma32_pages_limit;
  48
  49 MODULE_PARM_DESC(dma32_pages_limit, "Limit for the allocated DMA32 pages");
  50 module_param_named(dma32_pages_limit, ttm_dma32_pages_limit, ulong, 0644);
  51
  52 static atomic_long_t ttm_pages_allocated;
  53 static atomic_long_t ttm_dma32_pages_allocated;
  54
  55 /*
  56  * Allocates a ttm structure for the given BO.
  57  */
  58 int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)
  59 {
  60         struct ttm_device *bdev = bo->bdev;
  61         uint32_t page_flags = 0;
  62
  63         dma_resv_assert_held(bo->base.resv);
  64
  65         if (bo->ttm)
  66                 return 0;
  67
  68         switch (bo->type) {
  69         case ttm_bo_type_device:
  70                 if (zero_alloc)
  71                         page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC;
  72                 break;
  73         case ttm_bo_type_kernel:
  74                 break;
  75         case ttm_bo_type_sg:
  76                 page_flags |= TTM_PAGE_FLAG_SG;
  77                 break;
  78         default:
  79                 pr_err("Illegal buffer object type\n");
  80                 return -EINVAL;
  81         }
  82
  83         bo->ttm = bdev->funcs->ttm_tt_create(bo, page_flags);
  84         if (unlikely(bo->ttm == NULL))
  85                 return -ENOMEM;
  86
  87         return 0;
  88 }
  89
  90 /*
  91  * Allocates storage for pointers to the pages that back the ttm.
  92  */
  93 static int ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
  94 {
  95         ttm->pages = kvmalloc_array(ttm->num_pages, sizeof(void*),
  96                         GFP_KERNEL | __GFP_ZERO);
  97         if (!ttm->pages)
  98                 return -ENOMEM;
  99         return 0;
 100 }
 101
 102 static int ttm_dma_tt_alloc_page_directory(struct ttm_tt *ttm)
 103 {
 104         ttm->pages = kvmalloc_array(ttm->num_pages,
 105                                     sizeof(*ttm->pages) +
 106                                     sizeof(*ttm->dma_address),
 107                                     GFP_KERNEL | __GFP_ZERO);
 108         if (!ttm->pages)
 109                 return -ENOMEM;
 110
 111         ttm->dma_address = (void *)(ttm->pages + ttm->num_pages);
 112         return 0;
 113 }
 114
 115 static int ttm_sg_tt_alloc_page_directory(struct ttm_tt *ttm)
 116 {
 117         ttm->dma_address = kvmalloc_array(ttm->num_pages,
 118                                           sizeof(*ttm->dma_address),
 119                                           GFP_KERNEL | __GFP_ZERO);
 120         if (!ttm->dma_address)
 121                 return -ENOMEM;
 122         return 0;
 123 }
 124
 125 void ttm_tt_destroy_common(struct ttm_device *bdev, struct ttm_tt *ttm)
 126 {
 127         ttm_tt_unpopulate(bdev, ttm);
 128
 129         if (ttm->swap_storage)
 130                 fput(ttm->swap_storage);
 131
 132         ttm->swap_storage = NULL;
 133 }
 134 EXPORT_SYMBOL(ttm_tt_destroy_common);
 135
 136 void ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm)
 137 {
 138         bdev->funcs->ttm_tt_destroy(bdev, ttm);
 139 }
 140
 141 static void ttm_tt_init_fields(struct ttm_tt *ttm,
 142                                struct ttm_buffer_object *bo,
 143                                uint32_t page_flags,
 144                                enum ttm_caching caching)
 145 {
 146         ttm->num_pages = PAGE_ALIGN(bo->base.size) >> PAGE_SHIFT;
 147         ttm->caching = ttm_cached;
 148         ttm->page_flags = page_flags;
 149         ttm->dma_address = NULL;
 150         ttm->swap_storage = NULL;
 151         ttm->sg = bo->sg;
 152         ttm->caching = caching;
 153 }
 154
 155 int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
 156                 uint32_t page_flags, enum ttm_caching caching)
 157 {
 158         ttm_tt_init_fields(ttm, bo, page_flags, caching);
 159
 160         if (ttm_tt_alloc_page_directory(ttm)) {
 161                 pr_err("Failed allocating page table\n");
 162                 return -ENOMEM;
 163         }
 164         return 0;
 165 }
 166 EXPORT_SYMBOL(ttm_tt_init);
 167
 168 void ttm_tt_fini(struct ttm_tt *ttm)
 169 {
 170         if (ttm->pages)
 171                 kvfree(ttm->pages);
 172         else
 173                 kvfree(ttm->dma_address);
 174         ttm->pages = NULL;
 175         ttm->dma_address = NULL;
 176 }
 177 EXPORT_SYMBOL(ttm_tt_fini);
 178
 179 int ttm_sg_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
 180                    uint32_t page_flags, enum ttm_caching caching)
 181 {
 182         int ret;
 183
 184         ttm_tt_init_fields(ttm, bo, page_flags, caching);
 185
 186         if (page_flags & TTM_PAGE_FLAG_SG)
 187                 ret = ttm_sg_tt_alloc_page_directory(ttm);
 188         else
 189                 ret = ttm_dma_tt_alloc_page_directory(ttm);
 190         if (ret) {
 191                 pr_err("Failed allocating page table\n");
 192                 return -ENOMEM;
 193         }
 194         return 0;
 195 }
 196 EXPORT_SYMBOL(ttm_sg_tt_init);
 197
 198 int ttm_tt_swapin(struct ttm_tt *ttm)
 199 {
 200         struct address_space *swap_space;
 201         struct file *swap_storage;
 202         struct page *from_page;
 203         struct page *to_page;
 204         gfp_t gfp_mask;
 205         int i, ret;
 206
 207         swap_storage = ttm->swap_storage;
 208         BUG_ON(swap_storage == NULL);
 209
 210         swap_space = swap_storage->f_mapping;
 211         gfp_mask = mapping_gfp_mask(swap_space);
 212
 213         for (i = 0; i < ttm->num_pages; ++i) {
 214                 from_page = shmem_read_mapping_page_gfp(swap_space, i,
 215                                                         gfp_mask);
 216                 if (IS_ERR(from_page)) {
 217                         ret = PTR_ERR(from_page);
 218                         goto out_err;
 219                 }
 220                 to_page = ttm->pages[i];
 221                 if (unlikely(to_page == NULL)) {
 222                         ret = -ENOMEM;
 223                         goto out_err;
 224                 }
 225
 226                 copy_highpage(to_page, from_page);
 227                 put_page(from_page);
 228         }
 229
 230         fput(swap_storage);
 231         ttm->swap_storage = NULL;
 232         ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
 233
 234         return 0;
 235
 236 out_err:
 237         return ret;
 238 }
 239
 240 /**
 241  * ttm_tt_swapout - swap out tt object
 242  *
 243  * @bdev: TTM device structure.
 244  * @ttm: The struct ttm_tt.
 245  * @gfp_flags: Flags to use for memory allocation.
 246  *
 247  * Swapout a TT object to a shmem_file, return number of pages swapped out or
 248  * negative error code.
 249  */
 250 int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm,
 251                    gfp_t gfp_flags)
 252 {
 253         loff_t size = (loff_t)ttm->num_pages << PAGE_SHIFT;
 254         struct address_space *swap_space;
 255         struct file *swap_storage;
 256         struct page *from_page;
 257         struct page *to_page;
 258         int i, ret;
 259
 260         swap_storage = shmem_file_setup("ttm swap", size, 0);
 261         if (IS_ERR(swap_storage)) {
 262                 pr_err("Failed allocating swap storage\n");
 263                 return PTR_ERR(swap_storage);
 264         }
 265
 266         swap_space = swap_storage->f_mapping;
 267         gfp_flags &= mapping_gfp_mask(swap_space);
 268
 269         for (i = 0; i < ttm->num_pages; ++i) {
 270                 from_page = ttm->pages[i];
 271                 if (unlikely(from_page == NULL))
 272                         continue;
 273
 274                 to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_flags);
 275                 if (IS_ERR(to_page)) {
 276                         ret = PTR_ERR(to_page);
 277                         goto out_err;
 278                 }
 279                 copy_highpage(to_page, from_page);
 280                 set_page_dirty(to_page);
 281                 mark_page_accessed(to_page);
 282                 put_page(to_page);
 283         }
 284
 285         ttm_tt_unpopulate(bdev, ttm);
 286         ttm->swap_storage = swap_storage;
 287         ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
 288
 289         return ttm->num_pages;
 290
 291 out_err:
 292         fput(swap_storage);
 293
 294         return ret;
 295 }
 296
 297 static void ttm_tt_add_mapping(struct ttm_device *bdev, struct ttm_tt *ttm)
 298 {
 299         pgoff_t i;
 300
 301         if (ttm->page_flags & TTM_PAGE_FLAG_SG)
 302                 return;
 303
 304         for (i = 0; i < ttm->num_pages; ++i)
 305                 ttm->pages[i]->mapping = bdev->dev_mapping;
 306 }
 307
 308 int ttm_tt_populate(struct ttm_device *bdev,
 309                     struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
 310 {
 311         int ret;
 312
 313         if (!ttm)
 314                 return -EINVAL;
 315
 316         if (ttm_tt_is_populated(ttm))
 317                 return 0;
 318
 319         if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
 320                 atomic_long_add(ttm->num_pages, &ttm_pages_allocated);
 321                 if (bdev->pool.use_dma32)
 322                         atomic_long_add(ttm->num_pages,
 323                                         &ttm_dma32_pages_allocated);
 324         }
 325
 326         while (atomic_long_read(&ttm_pages_allocated) > ttm_pages_limit ||
 327                atomic_long_read(&ttm_dma32_pages_allocated) >
 328                ttm_dma32_pages_limit) {
 329
 330                 ret = ttm_global_swapout(ctx, GFP_KERNEL);
 331                 if (ret == 0)
 332                         break;
 333                 if (ret < 0)
 334                         goto error;
 335         }
 336
 337         if (bdev->funcs->ttm_tt_populate)
 338                 ret = bdev->funcs->ttm_tt_populate(bdev, ttm, ctx);
 339         else
 340                 ret = ttm_pool_alloc(&bdev->pool, ttm, ctx);
 341         if (ret)
 342                 goto error;
 343
 344         ttm_tt_add_mapping(bdev, ttm);
 345         ttm->page_flags |= TTM_PAGE_FLAG_PRIV_POPULATED;
 346         if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
 347                 ret = ttm_tt_swapin(ttm);
 348                 if (unlikely(ret != 0)) {
 349                         ttm_tt_unpopulate(bdev, ttm);
 350                         return ret;
 351                 }
 352         }
 353
 354         return 0;
 355
 356 error:
 357         if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
 358                 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);
 359                 if (bdev->pool.use_dma32)
 360                         atomic_long_sub(ttm->num_pages,
 361                                         &ttm_dma32_pages_allocated);
 362         }
 363         return ret;
 364 }
 365 EXPORT_SYMBOL(ttm_tt_populate);
 366
 367 static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
 368 {
 369         pgoff_t i;
 370         struct page **page = ttm->pages;
 371
 372         if (ttm->page_flags & TTM_PAGE_FLAG_SG)
 373                 return;
 374
 375         for (i = 0; i < ttm->num_pages; ++i) {
 376                 (*page)->mapping = NULL;
 377                 (*page++)->index = 0;
 378         }
 379 }
 380
 381 void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)
 382 {
 383         if (!ttm_tt_is_populated(ttm))
 384                 return;
 385
 386         ttm_tt_clear_mapping(ttm);
 387         if (bdev->funcs->ttm_tt_unpopulate)
 388                 bdev->funcs->ttm_tt_unpopulate(bdev, ttm);
 389         else
 390                 ttm_pool_free(&bdev->pool, ttm);
 391
 392         if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
 393                 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);
 394                 if (bdev->pool.use_dma32)
 395                         atomic_long_sub(ttm->num_pages,
 396                                         &ttm_dma32_pages_allocated);
 397         }
 398
 399         ttm->page_flags &= ~TTM_PAGE_FLAG_PRIV_POPULATED;
 400 }
 401
 402 #ifdef CONFIG_DEBUG_FS
 403
 404 /* Test the shrinker functions and dump the result */
 405 static int ttm_tt_debugfs_shrink_show(struct seq_file *m, void *data)
 406 {
 407         struct ttm_operation_ctx ctx = { false, false };
 408
 409         seq_printf(m, "%d\n", ttm_global_swapout(&ctx, GFP_KERNEL));
 410         return 0;
 411 }
 412 DEFINE_SHOW_ATTRIBUTE(ttm_tt_debugfs_shrink);
 413
 414 #endif
 415
 416
 417 /*
 418  * ttm_tt_mgr_init - register with the MM shrinker
 419  *
 420  * Register with the MM shrinker for swapping out BOs.
 421  */
 422 void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages)
 423 {
 424 #ifdef CONFIG_DEBUG_FS
 425         debugfs_create_file("tt_shrink", 0400, ttm_debugfs_root, NULL,
 426                             &ttm_tt_debugfs_shrink_fops);
 427 #endif
 428
 429         if (!ttm_pages_limit)
 430                 ttm_pages_limit = num_pages;
 431
 432         if (!ttm_dma32_pages_limit)
 433                 ttm_dma32_pages_limit = num_dma32_pages;
 434 }
 435
 436 static void ttm_kmap_iter_tt_map_local(struct ttm_kmap_iter *iter,
 437                                        struct dma_buf_map *dmap,
 438                                        pgoff_t i)
 439 {
 440         struct ttm_kmap_iter_tt *iter_tt =
 441                 container_of(iter, typeof(*iter_tt), base);
 442
 443         dma_buf_map_set_vaddr(dmap, kmap_local_page_prot(iter_tt->tt->pages[i],
 444                                                          iter_tt->prot));
 445 }
 446
 447 static void ttm_kmap_iter_tt_unmap_local(struct ttm_kmap_iter *iter,
 448                                          struct dma_buf_map *map)
 449 {
 450         kunmap_local(map->vaddr);
 451 }
 452
 453 static const struct ttm_kmap_iter_ops ttm_kmap_iter_tt_ops = {
 454         .map_local = ttm_kmap_iter_tt_map_local,
 455         .unmap_local = ttm_kmap_iter_tt_unmap_local,
 456         .maps_tt = true,
 457 };
 458
 459 /**
 460  * ttm_kmap_iter_tt_init - Initialize a struct ttm_kmap_iter_tt
 461  * @iter_tt: The struct ttm_kmap_iter_tt to initialize.
 462  * @tt: Struct ttm_tt holding page pointers of the struct ttm_resource.
 463  *
 464  * Return: Pointer to the embedded struct ttm_kmap_iter.
 465  */
 466 struct ttm_kmap_iter *
 467 ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt,
 468                       struct ttm_tt *tt)
 469 {
 470         iter_tt->base.ops = &ttm_kmap_iter_tt_ops;
 471         iter_tt->tt = tt;
 472         if (tt)
 473                 iter_tt->prot = ttm_prot_from_caching(tt->caching, PAGE_KERNEL);
 474         else
 475                 iter_tt->prot = PAGE_KERNEL;
 476
 477         return &iter_tt->base;
 478 }
 479 EXPORT_SYMBOL(ttm_kmap_iter_tt_init);