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(struct ttm_device *bdev, struct ttm_tt *ttm)
 126 {
 127         bdev->funcs->ttm_tt_destroy(bdev, ttm);
 128 }
 129
 130 static void ttm_tt_init_fields(struct ttm_tt *ttm,
 131                                struct ttm_buffer_object *bo,
 132                                uint32_t page_flags,
 133                                enum ttm_caching caching)
 134 {
 135         ttm->num_pages = PAGE_ALIGN(bo->base.size) >> PAGE_SHIFT;
 136         ttm->caching = ttm_cached;
 137         ttm->page_flags = page_flags;
 138         ttm->dma_address = NULL;
 139         ttm->swap_storage = NULL;
 140         ttm->sg = bo->sg;
 141         ttm->caching = caching;
 142 }
 143
 144 int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
 145                 uint32_t page_flags, enum ttm_caching caching)
 146 {
 147         ttm_tt_init_fields(ttm, bo, page_flags, caching);
 148
 149         if (ttm_tt_alloc_page_directory(ttm)) {
 150                 pr_err("Failed allocating page table\n");
 151                 return -ENOMEM;
 152         }
 153         return 0;
 154 }
 155 EXPORT_SYMBOL(ttm_tt_init);
 156
 157 void ttm_tt_fini(struct ttm_tt *ttm)
 158 {
 159         WARN_ON(ttm->page_flags & TTM_PAGE_FLAG_PRIV_POPULATED);
 160
 161         if (ttm->swap_storage)
 162                 fput(ttm->swap_storage);
 163         ttm->swap_storage = NULL;
 164
 165         if (ttm->pages)
 166                 kvfree(ttm->pages);
 167         else
 168                 kvfree(ttm->dma_address);
 169         ttm->pages = NULL;
 170         ttm->dma_address = NULL;
 171 }
 172 EXPORT_SYMBOL(ttm_tt_fini);
 173
 174 int ttm_sg_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
 175                    uint32_t page_flags, enum ttm_caching caching)
 176 {
 177         int ret;
 178
 179         ttm_tt_init_fields(ttm, bo, page_flags, caching);
 180
 181         if (page_flags & TTM_PAGE_FLAG_SG)
 182                 ret = ttm_sg_tt_alloc_page_directory(ttm);
 183         else
 184                 ret = ttm_dma_tt_alloc_page_directory(ttm);
 185         if (ret) {
 186                 pr_err("Failed allocating page table\n");
 187                 return -ENOMEM;
 188         }
 189         return 0;
 190 }
 191 EXPORT_SYMBOL(ttm_sg_tt_init);
 192
 193 int ttm_tt_swapin(struct ttm_tt *ttm)
 194 {
 195         struct address_space *swap_space;
 196         struct file *swap_storage;
 197         struct page *from_page;
 198         struct page *to_page;
 199         gfp_t gfp_mask;
 200         int i, ret;
 201
 202         swap_storage = ttm->swap_storage;
 203         BUG_ON(swap_storage == NULL);
 204
 205         swap_space = swap_storage->f_mapping;
 206         gfp_mask = mapping_gfp_mask(swap_space);
 207
 208         for (i = 0; i < ttm->num_pages; ++i) {
 209                 from_page = shmem_read_mapping_page_gfp(swap_space, i,
 210                                                         gfp_mask);
 211                 if (IS_ERR(from_page)) {
 212                         ret = PTR_ERR(from_page);
 213                         goto out_err;
 214                 }
 215                 to_page = ttm->pages[i];
 216                 if (unlikely(to_page == NULL)) {
 217                         ret = -ENOMEM;
 218                         goto out_err;
 219                 }
 220
 221                 copy_highpage(to_page, from_page);
 222                 put_page(from_page);
 223         }
 224
 225         fput(swap_storage);
 226         ttm->swap_storage = NULL;
 227         ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
 228
 229         return 0;
 230
 231 out_err:
 232         return ret;
 233 }
 234
 235 /**
 236  * ttm_tt_swapout - swap out tt object
 237  *
 238  * @bdev: TTM device structure.
 239  * @ttm: The struct ttm_tt.
 240  * @gfp_flags: Flags to use for memory allocation.
 241  *
 242  * Swapout a TT object to a shmem_file, return number of pages swapped out or
 243  * negative error code.
 244  */
 245 int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm,
 246                    gfp_t gfp_flags)
 247 {
 248         loff_t size = (loff_t)ttm->num_pages << PAGE_SHIFT;
 249         struct address_space *swap_space;
 250         struct file *swap_storage;
 251         struct page *from_page;
 252         struct page *to_page;
 253         int i, ret;
 254
 255         swap_storage = shmem_file_setup("ttm swap", size, 0);
 256         if (IS_ERR(swap_storage)) {
 257                 pr_err("Failed allocating swap storage\n");
 258                 return PTR_ERR(swap_storage);
 259         }
 260
 261         swap_space = swap_storage->f_mapping;
 262         gfp_flags &= mapping_gfp_mask(swap_space);
 263
 264         for (i = 0; i < ttm->num_pages; ++i) {
 265                 from_page = ttm->pages[i];
 266                 if (unlikely(from_page == NULL))
 267                         continue;
 268
 269                 to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_flags);
 270                 if (IS_ERR(to_page)) {
 271                         ret = PTR_ERR(to_page);
 272                         goto out_err;
 273                 }
 274                 copy_highpage(to_page, from_page);
 275                 set_page_dirty(to_page);
 276                 mark_page_accessed(to_page);
 277                 put_page(to_page);
 278         }
 279
 280         ttm_tt_unpopulate(bdev, ttm);
 281         ttm->swap_storage = swap_storage;
 282         ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
 283
 284         return ttm->num_pages;
 285
 286 out_err:
 287         fput(swap_storage);
 288
 289         return ret;
 290 }
 291
 292 static void ttm_tt_add_mapping(struct ttm_device *bdev, struct ttm_tt *ttm)
 293 {
 294         pgoff_t i;
 295
 296         if (ttm->page_flags & TTM_PAGE_FLAG_SG)
 297                 return;
 298
 299         for (i = 0; i < ttm->num_pages; ++i)
 300                 ttm->pages[i]->mapping = bdev->dev_mapping;
 301 }
 302
 303 int ttm_tt_populate(struct ttm_device *bdev,
 304                     struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
 305 {
 306         int ret;
 307
 308         if (!ttm)
 309                 return -EINVAL;
 310
 311         if (ttm_tt_is_populated(ttm))
 312                 return 0;
 313
 314         if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
 315                 atomic_long_add(ttm->num_pages, &ttm_pages_allocated);
 316                 if (bdev->pool.use_dma32)
 317                         atomic_long_add(ttm->num_pages,
 318                                         &ttm_dma32_pages_allocated);
 319         }
 320
 321         while (atomic_long_read(&ttm_pages_allocated) > ttm_pages_limit ||
 322                atomic_long_read(&ttm_dma32_pages_allocated) >
 323                ttm_dma32_pages_limit) {
 324
 325                 ret = ttm_global_swapout(ctx, GFP_KERNEL);
 326                 if (ret == 0)
 327                         break;
 328                 if (ret < 0)
 329                         goto error;
 330         }
 331
 332         if (bdev->funcs->ttm_tt_populate)
 333                 ret = bdev->funcs->ttm_tt_populate(bdev, ttm, ctx);
 334         else
 335                 ret = ttm_pool_alloc(&bdev->pool, ttm, ctx);
 336         if (ret)
 337                 goto error;
 338
 339         ttm_tt_add_mapping(bdev, ttm);
 340         ttm->page_flags |= TTM_PAGE_FLAG_PRIV_POPULATED;
 341         if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
 342                 ret = ttm_tt_swapin(ttm);
 343                 if (unlikely(ret != 0)) {
 344                         ttm_tt_unpopulate(bdev, ttm);
 345                         return ret;
 346                 }
 347         }
 348
 349         return 0;
 350
 351 error:
 352         if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
 353                 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);
 354                 if (bdev->pool.use_dma32)
 355                         atomic_long_sub(ttm->num_pages,
 356                                         &ttm_dma32_pages_allocated);
 357         }
 358         return ret;
 359 }
 360 EXPORT_SYMBOL(ttm_tt_populate);
 361
 362 static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
 363 {
 364         pgoff_t i;
 365         struct page **page = ttm->pages;
 366
 367         if (ttm->page_flags & TTM_PAGE_FLAG_SG)
 368                 return;
 369
 370         for (i = 0; i < ttm->num_pages; ++i)
 371                 (*page)->mapping = NULL;
 372 }
 373
 374 void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)
 375 {
 376         if (!ttm_tt_is_populated(ttm))
 377                 return;
 378
 379         ttm_tt_clear_mapping(ttm);
 380         if (bdev->funcs->ttm_tt_unpopulate)
 381                 bdev->funcs->ttm_tt_unpopulate(bdev, ttm);
 382         else
 383                 ttm_pool_free(&bdev->pool, ttm);
 384
 385         if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
 386                 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);
 387                 if (bdev->pool.use_dma32)
 388                         atomic_long_sub(ttm->num_pages,
 389                                         &ttm_dma32_pages_allocated);
 390         }
 391
 392         ttm->page_flags &= ~TTM_PAGE_FLAG_PRIV_POPULATED;
 393 }
 394
 395 #ifdef CONFIG_DEBUG_FS
 396
 397 /* Test the shrinker functions and dump the result */
 398 static int ttm_tt_debugfs_shrink_show(struct seq_file *m, void *data)
 399 {
 400         struct ttm_operation_ctx ctx = { false, false };
 401
 402         seq_printf(m, "%d\n", ttm_global_swapout(&ctx, GFP_KERNEL));
 403         return 0;
 404 }
 405 DEFINE_SHOW_ATTRIBUTE(ttm_tt_debugfs_shrink);
 406
 407 #endif
 408
 409
 410 /*
 411  * ttm_tt_mgr_init - register with the MM shrinker
 412  *
 413  * Register with the MM shrinker for swapping out BOs.
 414  */
 415 void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages)
 416 {
 417 #ifdef CONFIG_DEBUG_FS
 418         debugfs_create_file("tt_shrink", 0400, ttm_debugfs_root, NULL,
 419                             &ttm_tt_debugfs_shrink_fops);
 420 #endif
 421
 422         if (!ttm_pages_limit)
 423                 ttm_pages_limit = num_pages;
 424
 425         if (!ttm_dma32_pages_limit)
 426                 ttm_dma32_pages_limit = num_dma32_pages;
 427 }
 428
 429 static void ttm_kmap_iter_tt_map_local(struct ttm_kmap_iter *iter,
 430                                        struct dma_buf_map *dmap,
 431                                        pgoff_t i)
 432 {
 433         struct ttm_kmap_iter_tt *iter_tt =
 434                 container_of(iter, typeof(*iter_tt), base);
 435
 436         dma_buf_map_set_vaddr(dmap, kmap_local_page_prot(iter_tt->tt->pages[i],
 437                                                          iter_tt->prot));
 438 }
 439
 440 static void ttm_kmap_iter_tt_unmap_local(struct ttm_kmap_iter *iter,
 441                                          struct dma_buf_map *map)
 442 {
 443         kunmap_local(map->vaddr);
 444 }
 445
 446 static const struct ttm_kmap_iter_ops ttm_kmap_iter_tt_ops = {
 447         .map_local = ttm_kmap_iter_tt_map_local,
 448         .unmap_local = ttm_kmap_iter_tt_unmap_local,
 449         .maps_tt = true,
 450 };
 451
 452 /**
 453  * ttm_kmap_iter_tt_init - Initialize a struct ttm_kmap_iter_tt
 454  * @iter_tt: The struct ttm_kmap_iter_tt to initialize.
 455  * @tt: Struct ttm_tt holding page pointers of the struct ttm_resource.
 456  *
 457  * Return: Pointer to the embedded struct ttm_kmap_iter.
 458  */
 459 struct ttm_kmap_iter *
 460 ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt,
 461                       struct ttm_tt *tt)
 462 {
 463         iter_tt->base.ops = &ttm_kmap_iter_tt_ops;
 464         iter_tt->tt = tt;
 465         if (tt)
 466                 iter_tt->prot = ttm_prot_from_caching(tt->caching, PAGE_KERNEL);
 467         else
 468                 iter_tt->prot = PAGE_KERNEL;
 469
 470         return &iter_tt->base;
 471 }
 472 EXPORT_SYMBOL(ttm_kmap_iter_tt_init);