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