drivers/gpu/drm/ttm/ttm_bo.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 <drm/ttm/ttm_module.h>
  35 #include <drm/ttm/ttm_bo_driver.h>
  36 #include <drm/ttm/ttm_placement.h>
  37 #include <linux/jiffies.h>
  38 #include <linux/slab.h>
  39 #include <linux/sched.h>
  40 #include <linux/mm.h>
  41 #include <linux/file.h>
  42 #include <linux/module.h>
  43 #include <linux/atomic.h>
  44 #include <linux/reservation.h>
  45
  46 static void ttm_bo_global_kobj_release(struct kobject *kobj);
  47
  48 /**
  49  * ttm_global_mutex - protecting the global BO state
  50  */
  51 DEFINE_MUTEX(ttm_global_mutex);
  52 unsigned ttm_bo_glob_use_count;
  53 struct ttm_bo_global ttm_bo_glob;
  54
  55 static struct attribute ttm_bo_count = {
  56         .name = "bo_count",
  57         .mode = S_IRUGO
  58 };
  59
  60 /* default destructor */
  61 static void ttm_bo_default_destroy(struct ttm_buffer_object *bo)
  62 {
  63         kfree(bo);
  64 }
  65
  66 static inline int ttm_mem_type_from_place(const struct ttm_place *place,
  67                                           uint32_t *mem_type)
  68 {
  69         int pos;
  70
  71         pos = ffs(place->flags & TTM_PL_MASK_MEM);
  72         if (unlikely(!pos))
  73                 return -EINVAL;
  74
  75         *mem_type = pos - 1;
  76         return 0;
  77 }
  78
  79 static void ttm_mem_type_debug(struct ttm_bo_device *bdev, struct drm_printer *p,
  80                                int mem_type)
  81 {
  82         struct ttm_mem_type_manager *man = &bdev->man[mem_type];
  83
  84         drm_printf(p, "    has_type: %d\n", man->has_type);
  85         drm_printf(p, "    use_type: %d\n", man->use_type);
  86         drm_printf(p, "    flags: 0x%08X\n", man->flags);
  87         drm_printf(p, "    gpu_offset: 0x%08llX\n", man->gpu_offset);
  88         drm_printf(p, "    size: %llu\n", man->size);
  89         drm_printf(p, "    available_caching: 0x%08X\n", man->available_caching);
  90         drm_printf(p, "    default_caching: 0x%08X\n", man->default_caching);
  91         if (mem_type != TTM_PL_SYSTEM)
  92                 (*man->func->debug)(man, p);
  93 }
  94
  95 static void ttm_bo_mem_space_debug(struct ttm_buffer_object *bo,
  96                                         struct ttm_placement *placement)
  97 {
  98         struct drm_printer p = drm_debug_printer(TTM_PFX);
  99         int i, ret, mem_type;
 100
 101         drm_printf(&p, "No space for %p (%lu pages, %luK, %luM)\n",
 102                    bo, bo->mem.num_pages, bo->mem.size >> 10,
 103                    bo->mem.size >> 20);
 104         for (i = 0; i < placement->num_placement; i++) {
 105                 ret = ttm_mem_type_from_place(&placement->placement[i],
 106                                                 &mem_type);
 107                 if (ret)
 108                         return;
 109                 drm_printf(&p, "  placement[%d]=0x%08X (%d)\n",
 110                            i, placement->placement[i].flags, mem_type);
 111                 ttm_mem_type_debug(bo->bdev, &p, mem_type);
 112         }
 113 }
 114
 115 static ssize_t ttm_bo_global_show(struct kobject *kobj,
 116                                   struct attribute *attr,
 117                                   char *buffer)
 118 {
 119         struct ttm_bo_global *glob =
 120                 container_of(kobj, struct ttm_bo_global, kobj);
 121
 122         return snprintf(buffer, PAGE_SIZE, "%d\n",
 123                                 atomic_read(&glob->bo_count));
 124 }
 125
 126 static struct attribute *ttm_bo_global_attrs[] = {
 127         &ttm_bo_count,
 128         NULL
 129 };
 130
 131 static const struct sysfs_ops ttm_bo_global_ops = {
 132         .show = &ttm_bo_global_show
 133 };
 134
 135 static struct kobj_type ttm_bo_glob_kobj_type  = {
 136         .release = &ttm_bo_global_kobj_release,
 137         .sysfs_ops = &ttm_bo_global_ops,
 138         .default_attrs = ttm_bo_global_attrs
 139 };
 140
 141
 142 static inline uint32_t ttm_bo_type_flags(unsigned type)
 143 {
 144         return 1 << (type);
 145 }
 146
 147 static void ttm_bo_release_list(struct kref *list_kref)
 148 {
 149         struct ttm_buffer_object *bo =
 150             container_of(list_kref, struct ttm_buffer_object, list_kref);
 151         struct ttm_bo_device *bdev = bo->bdev;
 152         size_t acc_size = bo->acc_size;
 153
 154         BUG_ON(kref_read(&bo->list_kref));
 155         BUG_ON(kref_read(&bo->kref));
 156         BUG_ON(atomic_read(&bo->cpu_writers));
 157         BUG_ON(bo->mem.mm_node != NULL);
 158         BUG_ON(!list_empty(&bo->lru));
 159         BUG_ON(!list_empty(&bo->ddestroy));
 160         ttm_tt_destroy(bo->ttm);
 161         atomic_dec(&bo->bdev->glob->bo_count);
 162         dma_fence_put(bo->moving);
 163         reservation_object_fini(&bo->ttm_resv);
 164         mutex_destroy(&bo->wu_mutex);
 165         bo->destroy(bo);
 166         ttm_mem_global_free(bdev->glob->mem_glob, acc_size);
 167 }
 168
 169 static void ttm_bo_add_mem_to_lru(struct ttm_buffer_object *bo,
 170                                   struct ttm_mem_reg *mem)
 171 {
 172         struct ttm_bo_device *bdev = bo->bdev;
 173         struct ttm_mem_type_manager *man;
 174
 175         reservation_object_assert_held(bo->resv);
 176
 177         if (!list_empty(&bo->lru))
 178                 return;
 179
 180         if (mem->placement & TTM_PL_FLAG_NO_EVICT)
 181                 return;
 182
 183         man = &bdev->man[mem->mem_type];
 184         list_add_tail(&bo->lru, &man->lru[bo->priority]);
 185         kref_get(&bo->list_kref);
 186
 187         if (bo->ttm && !(bo->ttm->page_flags &
 188                          (TTM_PAGE_FLAG_SG | TTM_PAGE_FLAG_SWAPPED))) {
 189                 list_add_tail(&bo->swap, &bdev->glob->swap_lru[bo->priority]);
 190                 kref_get(&bo->list_kref);
 191         }
 192 }
 193
 194 void ttm_bo_add_to_lru(struct ttm_buffer_object *bo)
 195 {
 196         ttm_bo_add_mem_to_lru(bo, &bo->mem);
 197 }
 198 EXPORT_SYMBOL(ttm_bo_add_to_lru);
 199
 200 static void ttm_bo_ref_bug(struct kref *list_kref)
 201 {
 202         BUG();
 203 }
 204
 205 void ttm_bo_del_from_lru(struct ttm_buffer_object *bo)
 206 {
 207         struct ttm_bo_device *bdev = bo->bdev;
 208         bool notify = false;
 209
 210         if (!list_empty(&bo->swap)) {
 211                 list_del_init(&bo->swap);
 212                 kref_put(&bo->list_kref, ttm_bo_ref_bug);
 213                 notify = true;
 214         }
 215         if (!list_empty(&bo->lru)) {
 216                 list_del_init(&bo->lru);
 217                 kref_put(&bo->list_kref, ttm_bo_ref_bug);
 218                 notify = true;
 219         }
 220
 221         if (notify && bdev->driver->del_from_lru_notify)
 222                 bdev->driver->del_from_lru_notify(bo);
 223 }
 224
 225 void ttm_bo_del_sub_from_lru(struct ttm_buffer_object *bo)
 226 {
 227         struct ttm_bo_global *glob = bo->bdev->glob;
 228
 229         spin_lock(&glob->lru_lock);
 230         ttm_bo_del_from_lru(bo);
 231         spin_unlock(&glob->lru_lock);
 232 }
 233 EXPORT_SYMBOL(ttm_bo_del_sub_from_lru);
 234
 235 static void ttm_bo_bulk_move_set_pos(struct ttm_lru_bulk_move_pos *pos,
 236                                      struct ttm_buffer_object *bo)
 237 {
 238         if (!pos->first)
 239                 pos->first = bo;
 240         pos->last = bo;
 241 }
 242
 243 void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo,
 244                              struct ttm_lru_bulk_move *bulk)
 245 {
 246         reservation_object_assert_held(bo->resv);
 247
 248         ttm_bo_del_from_lru(bo);
 249         ttm_bo_add_to_lru(bo);
 250
 251         if (bulk && !(bo->mem.placement & TTM_PL_FLAG_NO_EVICT)) {
 252                 switch (bo->mem.mem_type) {
 253                 case TTM_PL_TT:
 254                         ttm_bo_bulk_move_set_pos(&bulk->tt[bo->priority], bo);
 255                         break;
 256
 257                 case TTM_PL_VRAM:
 258                         ttm_bo_bulk_move_set_pos(&bulk->vram[bo->priority], bo);
 259                         break;
 260                 }
 261                 if (bo->ttm && !(bo->ttm->page_flags &
 262                                  (TTM_PAGE_FLAG_SG | TTM_PAGE_FLAG_SWAPPED)))
 263                         ttm_bo_bulk_move_set_pos(&bulk->swap[bo->priority], bo);
 264         }
 265 }
 266 EXPORT_SYMBOL(ttm_bo_move_to_lru_tail);
 267
 268 void ttm_bo_bulk_move_lru_tail(struct ttm_lru_bulk_move *bulk)
 269 {
 270         unsigned i;
 271
 272         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
 273                 struct ttm_lru_bulk_move_pos *pos = &bulk->tt[i];
 274                 struct ttm_mem_type_manager *man;
 275
 276                 if (!pos->first)
 277                         continue;
 278
 279                 reservation_object_assert_held(pos->first->resv);
 280                 reservation_object_assert_held(pos->last->resv);
 281
 282                 man = &pos->first->bdev->man[TTM_PL_TT];
 283                 list_bulk_move_tail(&man->lru[i], &pos->first->lru,
 284                                     &pos->last->lru);
 285         }
 286
 287         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
 288                 struct ttm_lru_bulk_move_pos *pos = &bulk->vram[i];
 289                 struct ttm_mem_type_manager *man;
 290
 291                 if (!pos->first)
 292                         continue;
 293
 294                 reservation_object_assert_held(pos->first->resv);
 295                 reservation_object_assert_held(pos->last->resv);
 296
 297                 man = &pos->first->bdev->man[TTM_PL_VRAM];
 298                 list_bulk_move_tail(&man->lru[i], &pos->first->lru,
 299                                     &pos->last->lru);
 300         }
 301
 302         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
 303                 struct ttm_lru_bulk_move_pos *pos = &bulk->swap[i];
 304                 struct list_head *lru;
 305
 306                 if (!pos->first)
 307                         continue;
 308
 309                 reservation_object_assert_held(pos->first->resv);
 310                 reservation_object_assert_held(pos->last->resv);
 311
 312                 lru = &pos->first->bdev->glob->swap_lru[i];
 313                 list_bulk_move_tail(lru, &pos->first->swap, &pos->last->swap);
 314         }
 315 }
 316 EXPORT_SYMBOL(ttm_bo_bulk_move_lru_tail);
 317
 318 static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo,
 319                                   struct ttm_mem_reg *mem, bool evict,
 320                                   struct ttm_operation_ctx *ctx)
 321 {
 322         struct ttm_bo_device *bdev = bo->bdev;
 323         bool old_is_pci = ttm_mem_reg_is_pci(bdev, &bo->mem);
 324         bool new_is_pci = ttm_mem_reg_is_pci(bdev, mem);
 325         struct ttm_mem_type_manager *old_man = &bdev->man[bo->mem.mem_type];
 326         struct ttm_mem_type_manager *new_man = &bdev->man[mem->mem_type];
 327         int ret = 0;
 328
 329         if (old_is_pci || new_is_pci ||
 330             ((mem->placement & bo->mem.placement & TTM_PL_MASK_CACHING) == 0)) {
 331                 ret = ttm_mem_io_lock(old_man, true);
 332                 if (unlikely(ret != 0))
 333                         goto out_err;
 334                 ttm_bo_unmap_virtual_locked(bo);
 335                 ttm_mem_io_unlock(old_man);
 336         }
 337
 338         /*
 339          * Create and bind a ttm if required.
 340          */
 341
 342         if (!(new_man->flags & TTM_MEMTYPE_FLAG_FIXED)) {
 343                 if (bo->ttm == NULL) {
 344                         bool zero = !(old_man->flags & TTM_MEMTYPE_FLAG_FIXED);
 345                         ret = ttm_tt_create(bo, zero);
 346                         if (ret)
 347                                 goto out_err;
 348                 }
 349
 350                 ret = ttm_tt_set_placement_caching(bo->ttm, mem->placement);
 351                 if (ret)
 352                         goto out_err;
 353
 354                 if (mem->mem_type != TTM_PL_SYSTEM) {
 355                         ret = ttm_tt_bind(bo->ttm, mem, ctx);
 356                         if (ret)
 357                                 goto out_err;
 358                 }
 359
 360                 if (bo->mem.mem_type == TTM_PL_SYSTEM) {
 361                         if (bdev->driver->move_notify)
 362                                 bdev->driver->move_notify(bo, evict, mem);
 363                         bo->mem = *mem;
 364                         mem->mm_node = NULL;
 365                         goto moved;
 366                 }
 367         }
 368
 369         if (bdev->driver->move_notify)
 370                 bdev->driver->move_notify(bo, evict, mem);
 371
 372         if (!(old_man->flags & TTM_MEMTYPE_FLAG_FIXED) &&
 373             !(new_man->flags & TTM_MEMTYPE_FLAG_FIXED))
 374                 ret = ttm_bo_move_ttm(bo, ctx, mem);
 375         else if (bdev->driver->move)
 376                 ret = bdev->driver->move(bo, evict, ctx, mem);
 377         else
 378                 ret = ttm_bo_move_memcpy(bo, ctx, mem);
 379
 380         if (ret) {
 381                 if (bdev->driver->move_notify) {
 382                         swap(*mem, bo->mem);
 383                         bdev->driver->move_notify(bo, false, mem);
 384                         swap(*mem, bo->mem);
 385                 }
 386
 387                 goto out_err;
 388         }
 389
 390 moved:
 391         if (bo->evicted) {
 392                 if (bdev->driver->invalidate_caches) {
 393                         ret = bdev->driver->invalidate_caches(bdev, bo->mem.placement);
 394                         if (ret)
 395                                 pr_err("Can not flush read caches\n");
 396                 }
 397                 bo->evicted = false;
 398         }
 399
 400         if (bo->mem.mm_node)
 401                 bo->offset = (bo->mem.start << PAGE_SHIFT) +
 402                     bdev->man[bo->mem.mem_type].gpu_offset;
 403         else
 404                 bo->offset = 0;
 405
 406         ctx->bytes_moved += bo->num_pages << PAGE_SHIFT;
 407         return 0;
 408
 409 out_err:
 410         new_man = &bdev->man[bo->mem.mem_type];
 411         if (new_man->flags & TTM_MEMTYPE_FLAG_FIXED) {
 412                 ttm_tt_destroy(bo->ttm);
 413                 bo->ttm = NULL;
 414         }
 415
 416         return ret;
 417 }
 418
 419 /**
 420  * Call bo::reserved.
 421  * Will release GPU memory type usage on destruction.
 422  * This is the place to put in driver specific hooks to release
 423  * driver private resources.
 424  * Will release the bo::reserved lock.
 425  */
 426
 427 static void ttm_bo_cleanup_memtype_use(struct ttm_buffer_object *bo)
 428 {
 429         if (bo->bdev->driver->move_notify)
 430                 bo->bdev->driver->move_notify(bo, false, NULL);
 431
 432         ttm_tt_destroy(bo->ttm);
 433         bo->ttm = NULL;
 434         ttm_bo_mem_put(bo, &bo->mem);
 435 }
 436
 437 static int ttm_bo_individualize_resv(struct ttm_buffer_object *bo)
 438 {
 439         int r;
 440
 441         if (bo->resv == &bo->ttm_resv)
 442                 return 0;
 443
 444         BUG_ON(!reservation_object_trylock(&bo->ttm_resv));
 445
 446         r = reservation_object_copy_fences(&bo->ttm_resv, bo->resv);
 447         if (r)
 448                 reservation_object_unlock(&bo->ttm_resv);
 449
 450         return r;
 451 }
 452
 453 static void ttm_bo_flush_all_fences(struct ttm_buffer_object *bo)
 454 {
 455         struct reservation_object_list *fobj;
 456         struct dma_fence *fence;
 457         int i;
 458
 459         fobj = reservation_object_get_list(&bo->ttm_resv);
 460         fence = reservation_object_get_excl(&bo->ttm_resv);
 461         if (fence && !fence->ops->signaled)
 462                 dma_fence_enable_sw_signaling(fence);
 463
 464         for (i = 0; fobj && i < fobj->shared_count; ++i) {
 465                 fence = rcu_dereference_protected(fobj->shared[i],
 466                                         reservation_object_held(bo->resv));
 467
 468                 if (!fence->ops->signaled)
 469                         dma_fence_enable_sw_signaling(fence);
 470         }
 471 }
 472
 473 static void ttm_bo_cleanup_refs_or_queue(struct ttm_buffer_object *bo)
 474 {
 475         struct ttm_bo_device *bdev = bo->bdev;
 476         struct ttm_bo_global *glob = bdev->glob;
 477         int ret;
 478
 479         ret = ttm_bo_individualize_resv(bo);
 480         if (ret) {
 481                 /* Last resort, if we fail to allocate memory for the
 482                  * fences block for the BO to become idle
 483                  */
 484                 reservation_object_wait_timeout_rcu(bo->resv, true, false,
 485                                                     30 * HZ);
 486                 spin_lock(&glob->lru_lock);
 487                 goto error;
 488         }
 489
 490         spin_lock(&glob->lru_lock);
 491         ret = reservation_object_trylock(bo->resv) ? 0 : -EBUSY;
 492         if (!ret) {
 493                 if (reservation_object_test_signaled_rcu(&bo->ttm_resv, true)) {
 494                         ttm_bo_del_from_lru(bo);
 495                         spin_unlock(&glob->lru_lock);
 496                         if (bo->resv != &bo->ttm_resv)
 497                                 reservation_object_unlock(&bo->ttm_resv);
 498
 499                         ttm_bo_cleanup_memtype_use(bo);
 500                         reservation_object_unlock(bo->resv);
 501                         return;
 502                 }
 503
 504                 ttm_bo_flush_all_fences(bo);
 505
 506                 /*
 507                  * Make NO_EVICT bos immediately available to
 508                  * shrinkers, now that they are queued for
 509                  * destruction.
 510                  */
 511                 if (bo->mem.placement & TTM_PL_FLAG_NO_EVICT) {
 512                         bo->mem.placement &= ~TTM_PL_FLAG_NO_EVICT;
 513                         ttm_bo_add_to_lru(bo);
 514                 }
 515
 516                 reservation_object_unlock(bo->resv);
 517         }
 518         if (bo->resv != &bo->ttm_resv)
 519                 reservation_object_unlock(&bo->ttm_resv);
 520
 521 error:
 522         kref_get(&bo->list_kref);
 523         list_add_tail(&bo->ddestroy, &bdev->ddestroy);
 524         spin_unlock(&glob->lru_lock);
 525
 526         schedule_delayed_work(&bdev->wq,
 527                               ((HZ / 100) < 1) ? 1 : HZ / 100);
 528 }
 529
 530 /**
 531  * function ttm_bo_cleanup_refs
 532  * If bo idle, remove from delayed- and lru lists, and unref.
 533  * If not idle, do nothing.
 534  *
 535  * Must be called with lru_lock and reservation held, this function
 536  * will drop the lru lock and optionally the reservation lock before returning.
 537  *
 538  * @interruptible         Any sleeps should occur interruptibly.
 539  * @no_wait_gpu           Never wait for gpu. Return -EBUSY instead.
 540  * @unlock_resv           Unlock the reservation lock as well.
 541  */
 542
 543 static int ttm_bo_cleanup_refs(struct ttm_buffer_object *bo,
 544                                bool interruptible, bool no_wait_gpu,
 545                                bool unlock_resv)
 546 {
 547         struct ttm_bo_global *glob = bo->bdev->glob;
 548         struct reservation_object *resv;
 549         int ret;
 550
 551         if (unlikely(list_empty(&bo->ddestroy)))
 552                 resv = bo->resv;
 553         else
 554                 resv = &bo->ttm_resv;
 555
 556         if (reservation_object_test_signaled_rcu(resv, true))
 557                 ret = 0;
 558         else
 559                 ret = -EBUSY;
 560
 561         if (ret && !no_wait_gpu) {
 562                 long lret;
 563
 564                 if (unlock_resv)
 565                         reservation_object_unlock(bo->resv);
 566                 spin_unlock(&glob->lru_lock);
 567
 568                 lret = reservation_object_wait_timeout_rcu(resv, true,
 569                                                            interruptible,
 570                                                            30 * HZ);
 571
 572                 if (lret < 0)
 573                         return lret;
 574                 else if (lret == 0)
 575                         return -EBUSY;
 576
 577                 spin_lock(&glob->lru_lock);
 578                 if (unlock_resv && !reservation_object_trylock(bo->resv)) {
 579                         /*
 580                          * We raced, and lost, someone else holds the reservation now,
 581                          * and is probably busy in ttm_bo_cleanup_memtype_use.
 582                          *
 583                          * Even if it's not the case, because we finished waiting any
 584                          * delayed destruction would succeed, so just return success
 585                          * here.
 586                          */
 587                         spin_unlock(&glob->lru_lock);
 588                         return 0;
 589                 }
 590                 ret = 0;
 591         }
 592
 593         if (ret || unlikely(list_empty(&bo->ddestroy))) {
 594                 if (unlock_resv)
 595                         reservation_object_unlock(bo->resv);
 596                 spin_unlock(&glob->lru_lock);
 597                 return ret;
 598         }
 599
 600         ttm_bo_del_from_lru(bo);
 601         list_del_init(&bo->ddestroy);
 602         kref_put(&bo->list_kref, ttm_bo_ref_bug);
 603
 604         spin_unlock(&glob->lru_lock);
 605         ttm_bo_cleanup_memtype_use(bo);
 606
 607         if (unlock_resv)
 608                 reservation_object_unlock(bo->resv);
 609
 610         return 0;
 611 }
 612
 613 /**
 614  * Traverse the delayed list, and call ttm_bo_cleanup_refs on all
 615  * encountered buffers.
 616  */
 617 static bool ttm_bo_delayed_delete(struct ttm_bo_device *bdev, bool remove_all)
 618 {
 619         struct ttm_bo_global *glob = bdev->glob;
 620         struct list_head removed;
 621         bool empty;
 622
 623         INIT_LIST_HEAD(&removed);
 624
 625         spin_lock(&glob->lru_lock);
 626         while (!list_empty(&bdev->ddestroy)) {
 627                 struct ttm_buffer_object *bo;
 628
 629                 bo = list_first_entry(&bdev->ddestroy, struct ttm_buffer_object,
 630                                       ddestroy);
 631                 kref_get(&bo->list_kref);
 632                 list_move_tail(&bo->ddestroy, &removed);
 633
 634                 if (remove_all || bo->resv != &bo->ttm_resv) {
 635                         spin_unlock(&glob->lru_lock);
 636                         reservation_object_lock(bo->resv, NULL);
 637
 638                         spin_lock(&glob->lru_lock);
 639                         ttm_bo_cleanup_refs(bo, false, !remove_all, true);
 640
 641                 } else if (reservation_object_trylock(bo->resv)) {
 642                         ttm_bo_cleanup_refs(bo, false, !remove_all, true);
 643                 } else {
 644                         spin_unlock(&glob->lru_lock);
 645                 }
 646
 647                 kref_put(&bo->list_kref, ttm_bo_release_list);
 648                 spin_lock(&glob->lru_lock);
 649         }
 650         list_splice_tail(&removed, &bdev->ddestroy);
 651         empty = list_empty(&bdev->ddestroy);
 652         spin_unlock(&glob->lru_lock);
 653
 654         return empty;
 655 }
 656
 657 static void ttm_bo_delayed_workqueue(struct work_struct *work)
 658 {
 659         struct ttm_bo_device *bdev =
 660             container_of(work, struct ttm_bo_device, wq.work);
 661
 662         if (!ttm_bo_delayed_delete(bdev, false))
 663                 schedule_delayed_work(&bdev->wq,
 664                                       ((HZ / 100) < 1) ? 1 : HZ / 100);
 665 }
 666
 667 static void ttm_bo_release(struct kref *kref)
 668 {
 669         struct ttm_buffer_object *bo =
 670             container_of(kref, struct ttm_buffer_object, kref);
 671         struct ttm_bo_device *bdev = bo->bdev;
 672         struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type];
 673
 674         if (bo->bdev->driver->release_notify)
 675                 bo->bdev->driver->release_notify(bo);
 676
 677         drm_vma_offset_remove(&bdev->vma_manager, &bo->vma_node);
 678         ttm_mem_io_lock(man, false);
 679         ttm_mem_io_free_vm(bo);
 680         ttm_mem_io_unlock(man);
 681         ttm_bo_cleanup_refs_or_queue(bo);
 682         kref_put(&bo->list_kref, ttm_bo_release_list);
 683 }
 684
 685 void ttm_bo_put(struct ttm_buffer_object *bo)
 686 {
 687         kref_put(&bo->kref, ttm_bo_release);
 688 }
 689 EXPORT_SYMBOL(ttm_bo_put);
 690
 691 int ttm_bo_lock_delayed_workqueue(struct ttm_bo_device *bdev)
 692 {
 693         return cancel_delayed_work_sync(&bdev->wq);
 694 }
 695 EXPORT_SYMBOL(ttm_bo_lock_delayed_workqueue);
 696
 697 void ttm_bo_unlock_delayed_workqueue(struct ttm_bo_device *bdev, int resched)
 698 {
 699         if (resched)
 700                 schedule_delayed_work(&bdev->wq,
 701                                       ((HZ / 100) < 1) ? 1 : HZ / 100);
 702 }
 703 EXPORT_SYMBOL(ttm_bo_unlock_delayed_workqueue);
 704
 705 static int ttm_bo_evict(struct ttm_buffer_object *bo,
 706                         struct ttm_operation_ctx *ctx)
 707 {
 708         struct ttm_bo_device *bdev = bo->bdev;
 709         struct ttm_mem_reg evict_mem;
 710         struct ttm_placement placement;
 711         int ret = 0;
 712
 713         reservation_object_assert_held(bo->resv);
 714
 715         placement.num_placement = 0;
 716         placement.num_busy_placement = 0;
 717         bdev->driver->evict_flags(bo, &placement);
 718
 719         if (!placement.num_placement && !placement.num_busy_placement) {
 720                 ret = ttm_bo_pipeline_gutting(bo);
 721                 if (ret)
 722                         return ret;
 723
 724                 return ttm_tt_create(bo, false);
 725         }
 726
 727         evict_mem = bo->mem;
 728         evict_mem.mm_node = NULL;
 729         evict_mem.bus.io_reserved_vm = false;
 730         evict_mem.bus.io_reserved_count = 0;
 731
 732         ret = ttm_bo_mem_space(bo, &placement, &evict_mem, ctx);
 733         if (ret) {
 734                 if (ret != -ERESTARTSYS) {
 735                         pr_err("Failed to find memory space for buffer 0x%p eviction\n",
 736                                bo);
 737                         ttm_bo_mem_space_debug(bo, &placement);
 738                 }
 739                 goto out;
 740         }
 741
 742         ret = ttm_bo_handle_move_mem(bo, &evict_mem, true, ctx);
 743         if (unlikely(ret)) {
 744                 if (ret != -ERESTARTSYS)
 745                         pr_err("Buffer eviction failed\n");
 746                 ttm_bo_mem_put(bo, &evict_mem);
 747                 goto out;
 748         }
 749         bo->evicted = true;
 750 out:
 751         return ret;
 752 }
 753
 754 bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
 755                               const struct ttm_place *place)
 756 {
 757         /* Don't evict this BO if it's outside of the
 758          * requested placement range
 759          */
 760         if (place->fpfn >= (bo->mem.start + bo->mem.size) ||
 761             (place->lpfn && place->lpfn <= bo->mem.start))
 762                 return false;
 763
 764         return true;
 765 }
 766 EXPORT_SYMBOL(ttm_bo_eviction_valuable);
 767
 768 /**
 769  * Check the target bo is allowable to be evicted or swapout, including cases:
 770  *
 771  * a. if share same reservation object with ctx->resv, have assumption
 772  * reservation objects should already be locked, so not lock again and
 773  * return true directly when either the opreation allow_reserved_eviction
 774  * or the target bo already is in delayed free list;
 775  *
 776  * b. Otherwise, trylock it.
 777  */
 778 static bool ttm_bo_evict_swapout_allowable(struct ttm_buffer_object *bo,
 779                         struct ttm_operation_ctx *ctx, bool *locked, bool *busy)
 780 {
 781         bool ret = false;
 782
 783         if (bo->resv == ctx->resv) {
 784                 reservation_object_assert_held(bo->resv);
 785                 if (ctx->flags & TTM_OPT_FLAG_ALLOW_RES_EVICT
 786                     || !list_empty(&bo->ddestroy))
 787                         ret = true;
 788                 *locked = false;
 789                 if (busy)
 790                         *busy = false;
 791         } else {
 792                 ret = reservation_object_trylock(bo->resv);
 793                 *locked = ret;
 794                 if (busy)
 795                         *busy = !ret;
 796         }
 797
 798         return ret;
 799 }
 800
 801 /**
 802  * ttm_mem_evict_wait_busy - wait for a busy BO to become available
 803  *
 804  * @busy_bo: BO which couldn't be locked with trylock
 805  * @ctx: operation context
 806  * @ticket: acquire ticket
 807  *
 808  * Try to lock a busy buffer object to avoid failing eviction.
 809  */
 810 static int ttm_mem_evict_wait_busy(struct ttm_buffer_object *busy_bo,
 811                                    struct ttm_operation_ctx *ctx,
 812                                    struct ww_acquire_ctx *ticket)
 813 {
 814         int r;
 815
 816         if (!busy_bo || !ticket)
 817                 return -EBUSY;
 818
 819         if (ctx->interruptible)
 820                 r = reservation_object_lock_interruptible(busy_bo->resv,
 821                                                           ticket);
 822         else
 823                 r = reservation_object_lock(busy_bo->resv, ticket);
 824
 825         /*
 826          * TODO: It would be better to keep the BO locked until allocation is at
 827          * least tried one more time, but that would mean a much larger rework
 828          * of TTM.
 829          */
 830         if (!r)
 831                 reservation_object_unlock(busy_bo->resv);
 832
 833         return r == -EDEADLK ? -EBUSY : r;
 834 }
 835
 836 static int ttm_mem_evict_first(struct ttm_bo_device *bdev,
 837                                uint32_t mem_type,
 838                                const struct ttm_place *place,
 839                                struct ttm_operation_ctx *ctx,
 840                                struct ww_acquire_ctx *ticket)
 841 {
 842         struct ttm_buffer_object *bo = NULL, *busy_bo = NULL;
 843         struct ttm_bo_global *glob = bdev->glob;
 844         struct ttm_mem_type_manager *man = &bdev->man[mem_type];
 845         bool locked = false;
 846         unsigned i;
 847         int ret;
 848
 849         spin_lock(&glob->lru_lock);
 850         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
 851                 list_for_each_entry(bo, &man->lru[i], lru) {
 852                         bool busy;
 853
 854                         if (!ttm_bo_evict_swapout_allowable(bo, ctx, &locked,
 855                                                             &busy)) {
 856                                 if (busy && !busy_bo &&
 857                                     bo->resv->lock.ctx != ticket)
 858                                         busy_bo = bo;
 859                                 continue;
 860                         }
 861
 862                         if (place && !bdev->driver->eviction_valuable(bo,
 863                                                                       place)) {
 864                                 if (locked)
 865                                         reservation_object_unlock(bo->resv);
 866                                 continue;
 867                         }
 868                         break;
 869                 }
 870
 871                 /* If the inner loop terminated early, we have our candidate */
 872                 if (&bo->lru != &man->lru[i])
 873                         break;
 874
 875                 bo = NULL;
 876         }
 877
 878         if (!bo) {
 879                 if (busy_bo)
 880                         ttm_bo_get(busy_bo);
 881                 spin_unlock(&glob->lru_lock);
 882                 ret = ttm_mem_evict_wait_busy(busy_bo, ctx, ticket);
 883                 if (busy_bo)
 884                         ttm_bo_put(busy_bo);
 885                 return ret;
 886         }
 887
 888         kref_get(&bo->list_kref);
 889
 890         if (!list_empty(&bo->ddestroy)) {
 891                 ret = ttm_bo_cleanup_refs(bo, ctx->interruptible,
 892                                           ctx->no_wait_gpu, locked);
 893                 kref_put(&bo->list_kref, ttm_bo_release_list);
 894                 return ret;
 895         }
 896
 897         ttm_bo_del_from_lru(bo);
 898         spin_unlock(&glob->lru_lock);
 899
 900         ret = ttm_bo_evict(bo, ctx);
 901         if (locked) {
 902                 ttm_bo_unreserve(bo);
 903         } else {
 904                 spin_lock(&glob->lru_lock);
 905                 ttm_bo_add_to_lru(bo);
 906                 spin_unlock(&glob->lru_lock);
 907         }
 908
 909         kref_put(&bo->list_kref, ttm_bo_release_list);
 910         return ret;
 911 }
 912
 913 void ttm_bo_mem_put(struct ttm_buffer_object *bo, struct ttm_mem_reg *mem)
 914 {
 915         struct ttm_mem_type_manager *man = &bo->bdev->man[mem->mem_type];
 916
 917         if (mem->mm_node)
 918                 (*man->func->put_node)(man, mem);
 919 }
 920 EXPORT_SYMBOL(ttm_bo_mem_put);
 921
 922 /**
 923  * Add the last move fence to the BO and reserve a new shared slot.
 924  */
 925 static int ttm_bo_add_move_fence(struct ttm_buffer_object *bo,
 926                                  struct ttm_mem_type_manager *man,
 927                                  struct ttm_mem_reg *mem)
 928 {
 929         struct dma_fence *fence;
 930         int ret;
 931
 932         spin_lock(&man->move_lock);
 933         fence = dma_fence_get(man->move);
 934         spin_unlock(&man->move_lock);
 935
 936         if (fence) {
 937                 reservation_object_add_shared_fence(bo->resv, fence);
 938
 939                 ret = reservation_object_reserve_shared(bo->resv, 1);
 940                 if (unlikely(ret)) {
 941                         dma_fence_put(fence);
 942                         return ret;
 943                 }
 944
 945                 dma_fence_put(bo->moving);
 946                 bo->moving = fence;
 947         }
 948
 949         return 0;
 950 }
 951
 952 /**
 953  * Repeatedly evict memory from the LRU for @mem_type until we create enough
 954  * space, or we've evicted everything and there isn't enough space.
 955  */
 956 static int ttm_bo_mem_force_space(struct ttm_buffer_object *bo,
 957                                   const struct ttm_place *place,
 958                                   struct ttm_mem_reg *mem,
 959                                   struct ttm_operation_ctx *ctx)
 960 {
 961         struct ttm_bo_device *bdev = bo->bdev;
 962         struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
 963         int ret;
 964
 965         do {
 966                 ret = (*man->func->get_node)(man, bo, place, mem);
 967                 if (unlikely(ret != 0))
 968                         return ret;
 969                 if (mem->mm_node)
 970                         break;
 971                 ret = ttm_mem_evict_first(bdev, mem->mem_type, place, ctx,
 972                                           bo->resv->lock.ctx);
 973                 if (unlikely(ret != 0))
 974                         return ret;
 975         } while (1);
 976
 977         return ttm_bo_add_move_fence(bo, man, mem);
 978 }
 979
 980 static uint32_t ttm_bo_select_caching(struct ttm_mem_type_manager *man,
 981                                       uint32_t cur_placement,
 982                                       uint32_t proposed_placement)
 983 {
 984         uint32_t caching = proposed_placement & TTM_PL_MASK_CACHING;
 985         uint32_t result = proposed_placement & ~TTM_PL_MASK_CACHING;
 986
 987         /**
 988          * Keep current caching if possible.
 989          */
 990
 991         if ((cur_placement & caching) != 0)
 992                 result |= (cur_placement & caching);
 993         else if ((man->default_caching & caching) != 0)
 994                 result |= man->default_caching;
 995         else if ((TTM_PL_FLAG_CACHED & caching) != 0)
 996                 result |= TTM_PL_FLAG_CACHED;
 997         else if ((TTM_PL_FLAG_WC & caching) != 0)
 998                 result |= TTM_PL_FLAG_WC;
 999         else if ((TTM_PL_FLAG_UNCACHED & caching) != 0)
1000                 result |= TTM_PL_FLAG_UNCACHED;
1001
1002         return result;
1003 }
1004
1005 static bool ttm_bo_mt_compatible(struct ttm_mem_type_manager *man,
1006                                  uint32_t mem_type,
1007                                  const struct ttm_place *place,
1008                                  uint32_t *masked_placement)
1009 {
1010         uint32_t cur_flags = ttm_bo_type_flags(mem_type);
1011
1012         if ((cur_flags & place->flags & TTM_PL_MASK_MEM) == 0)
1013                 return false;
1014
1015         if ((place->flags & man->available_caching) == 0)
1016                 return false;
1017
1018         cur_flags |= (place->flags & man->available_caching);
1019
1020         *masked_placement = cur_flags;
1021         return true;
1022 }
1023
1024 /**
1025  * ttm_bo_mem_placement - check if placement is compatible
1026  * @bo: BO to find memory for
1027  * @place: where to search
1028  * @mem: the memory object to fill in
1029  * @ctx: operation context
1030  *
1031  * Check if placement is compatible and fill in mem structure.
1032  * Returns -EBUSY if placement won't work or negative error code.
1033  * 0 when placement can be used.
1034  */
1035 static int ttm_bo_mem_placement(struct ttm_buffer_object *bo,
1036                                 const struct ttm_place *place,
1037                                 struct ttm_mem_reg *mem,
1038                                 struct ttm_operation_ctx *ctx)
1039 {
1040         struct ttm_bo_device *bdev = bo->bdev;
1041         uint32_t mem_type = TTM_PL_SYSTEM;
1042         struct ttm_mem_type_manager *man;
1043         uint32_t cur_flags = 0;
1044         int ret;
1045
1046         ret = ttm_mem_type_from_place(place, &mem_type);
1047         if (ret)
1048                 return ret;
1049
1050         man = &bdev->man[mem_type];
1051         if (!man->has_type || !man->use_type)
1052                 return -EBUSY;
1053
1054         if (!ttm_bo_mt_compatible(man, mem_type, place, &cur_flags))
1055                 return -EBUSY;
1056
1057         cur_flags = ttm_bo_select_caching(man, bo->mem.placement, cur_flags);
1058         /*
1059          * Use the access and other non-mapping-related flag bits from
1060          * the memory placement flags to the current flags
1061          */
1062         ttm_flag_masked(&cur_flags, place->flags, ~TTM_PL_MASK_MEMTYPE);
1063
1064         mem->mem_type = mem_type;
1065         mem->placement = cur_flags;
1066
1067         if (bo->mem.mem_type < mem_type && !list_empty(&bo->lru)) {
1068                 spin_lock(&bo->bdev->glob->lru_lock);
1069                 ttm_bo_del_from_lru(bo);
1070                 ttm_bo_add_mem_to_lru(bo, mem);
1071                 spin_unlock(&bo->bdev->glob->lru_lock);
1072         }
1073
1074         return 0;
1075 }
1076
1077 /**
1078  * Creates space for memory region @mem according to its type.
1079  *
1080  * This function first searches for free space in compatible memory types in
1081  * the priority order defined by the driver.  If free space isn't found, then
1082  * ttm_bo_mem_force_space is attempted in priority order to evict and find
1083  * space.
1084  */
1085 int ttm_bo_mem_space(struct ttm_buffer_object *bo,
1086                         struct ttm_placement *placement,
1087                         struct ttm_mem_reg *mem,
1088                         struct ttm_operation_ctx *ctx)
1089 {
1090         struct ttm_bo_device *bdev = bo->bdev;
1091         bool type_found = false;
1092         int i, ret;
1093
1094         ret = reservation_object_reserve_shared(bo->resv, 1);
1095         if (unlikely(ret))
1096                 return ret;
1097
1098         mem->mm_node = NULL;
1099         for (i = 0; i < placement->num_placement; ++i) {
1100                 const struct ttm_place *place = &placement->placement[i];
1101                 struct ttm_mem_type_manager *man;
1102
1103                 ret = ttm_bo_mem_placement(bo, place, mem, ctx);
1104                 if (ret == -EBUSY)
1105                         continue;
1106                 if (ret)
1107                         goto error;
1108
1109                 type_found = true;
1110                 mem->mm_node = NULL;
1111                 if (mem->mem_type == TTM_PL_SYSTEM)
1112                         return 0;
1113
1114                 man = &bdev->man[mem->mem_type];
1115                 ret = (*man->func->get_node)(man, bo, place, mem);
1116                 if (unlikely(ret))
1117                         goto error;
1118
1119                 if (mem->mm_node) {
1120                         ret = ttm_bo_add_move_fence(bo, man, mem);
1121                         if (unlikely(ret)) {
1122                                 (*man->func->put_node)(man, mem);
1123                                 goto error;
1124                         }
1125                         return 0;
1126                 }
1127         }
1128
1129         for (i = 0; i < placement->num_busy_placement; ++i) {
1130                 const struct ttm_place *place = &placement->busy_placement[i];
1131
1132                 ret = ttm_bo_mem_placement(bo, place, mem, ctx);
1133                 if (ret == -EBUSY)
1134                         continue;
1135                 if (ret)
1136                         goto error;
1137
1138                 type_found = true;
1139                 mem->mm_node = NULL;
1140                 if (mem->mem_type == TTM_PL_SYSTEM)
1141                         return 0;
1142
1143                 ret = ttm_bo_mem_force_space(bo, place, mem, ctx);
1144                 if (ret == 0 && mem->mm_node)
1145                         return 0;
1146
1147                 if (ret && ret != -EBUSY)
1148                         goto error;
1149         }
1150
1151         ret = -ENOMEM;
1152         if (!type_found) {
1153                 pr_err(TTM_PFX "No compatible memory type found\n");
1154                 ret = -EINVAL;
1155         }
1156
1157 error:
1158         if (bo->mem.mem_type == TTM_PL_SYSTEM && !list_empty(&bo->lru)) {
1159                 spin_lock(&bo->bdev->glob->lru_lock);
1160                 ttm_bo_move_to_lru_tail(bo, NULL);
1161                 spin_unlock(&bo->bdev->glob->lru_lock);
1162         }
1163
1164         return ret;
1165 }
1166 EXPORT_SYMBOL(ttm_bo_mem_space);
1167
1168 static int ttm_bo_move_buffer(struct ttm_buffer_object *bo,
1169                               struct ttm_placement *placement,
1170                               struct ttm_operation_ctx *ctx)
1171 {
1172         int ret = 0;
1173         struct ttm_mem_reg mem;
1174
1175         reservation_object_assert_held(bo->resv);
1176
1177         mem.num_pages = bo->num_pages;
1178         mem.size = mem.num_pages << PAGE_SHIFT;
1179         mem.page_alignment = bo->mem.page_alignment;
1180         mem.bus.io_reserved_vm = false;
1181         mem.bus.io_reserved_count = 0;
1182         /*
1183          * Determine where to move the buffer.
1184          */
1185         ret = ttm_bo_mem_space(bo, placement, &mem, ctx);
1186         if (ret)
1187                 goto out_unlock;
1188         ret = ttm_bo_handle_move_mem(bo, &mem, false, ctx);
1189 out_unlock:
1190         if (ret && mem.mm_node)
1191                 ttm_bo_mem_put(bo, &mem);
1192         return ret;
1193 }
1194
1195 static bool ttm_bo_places_compat(const struct ttm_place *places,
1196                                  unsigned num_placement,
1197                                  struct ttm_mem_reg *mem,
1198                                  uint32_t *new_flags)
1199 {
1200         unsigned i;
1201
1202         for (i = 0; i < num_placement; i++) {
1203                 const struct ttm_place *heap = &places[i];
1204
1205                 if (mem->mm_node && (mem->start < heap->fpfn ||
1206                      (heap->lpfn != 0 && (mem->start + mem->num_pages) > heap->lpfn)))
1207                         continue;
1208
1209                 *new_flags = heap->flags;
1210                 if ((*new_flags & mem->placement & TTM_PL_MASK_CACHING) &&
1211                     (*new_flags & mem->placement & TTM_PL_MASK_MEM) &&
1212                     (!(*new_flags & TTM_PL_FLAG_CONTIGUOUS) ||
1213                      (mem->placement & TTM_PL_FLAG_CONTIGUOUS)))
1214                         return true;
1215         }
1216         return false;
1217 }
1218
1219 bool ttm_bo_mem_compat(struct ttm_placement *placement,
1220                        struct ttm_mem_reg *mem,
1221                        uint32_t *new_flags)
1222 {
1223         if (ttm_bo_places_compat(placement->placement, placement->num_placement,
1224                                  mem, new_flags))
1225                 return true;
1226
1227         if ((placement->busy_placement != placement->placement ||
1228              placement->num_busy_placement > placement->num_placement) &&
1229             ttm_bo_places_compat(placement->busy_placement,
1230                                  placement->num_busy_placement,
1231                                  mem, new_flags))
1232                 return true;
1233
1234         return false;
1235 }
1236 EXPORT_SYMBOL(ttm_bo_mem_compat);
1237
1238 int ttm_bo_validate(struct ttm_buffer_object *bo,
1239                     struct ttm_placement *placement,
1240                     struct ttm_operation_ctx *ctx)
1241 {
1242         int ret;
1243         uint32_t new_flags;
1244
1245         reservation_object_assert_held(bo->resv);
1246         /*
1247          * Check whether we need to move buffer.
1248          */
1249         if (!ttm_bo_mem_compat(placement, &bo->mem, &new_flags)) {
1250                 ret = ttm_bo_move_buffer(bo, placement, ctx);
1251                 if (ret)
1252                         return ret;
1253         } else {
1254                 /*
1255                  * Use the access and other non-mapping-related flag bits from
1256                  * the compatible memory placement flags to the active flags
1257                  */
1258                 ttm_flag_masked(&bo->mem.placement, new_flags,
1259                                 ~TTM_PL_MASK_MEMTYPE);
1260         }
1261         /*
1262          * We might need to add a TTM.
1263          */
1264         if (bo->mem.mem_type == TTM_PL_SYSTEM && bo->ttm == NULL) {
1265                 ret = ttm_tt_create(bo, true);
1266                 if (ret)
1267                         return ret;
1268         }
1269         return 0;
1270 }
1271 EXPORT_SYMBOL(ttm_bo_validate);
1272
1273 int ttm_bo_init_reserved(struct ttm_bo_device *bdev,
1274                          struct ttm_buffer_object *bo,
1275                          unsigned long size,
1276                          enum ttm_bo_type type,
1277                          struct ttm_placement *placement,
1278                          uint32_t page_alignment,
1279                          struct ttm_operation_ctx *ctx,
1280                          size_t acc_size,
1281                          struct sg_table *sg,
1282                          struct reservation_object *resv,
1283                          void (*destroy) (struct ttm_buffer_object *))
1284 {
1285         int ret = 0;
1286         unsigned long num_pages;
1287         struct ttm_mem_global *mem_glob = bdev->glob->mem_glob;
1288         bool locked;
1289
1290         ret = ttm_mem_global_alloc(mem_glob, acc_size, ctx);
1291         if (ret) {
1292                 pr_err("Out of kernel memory\n");
1293                 if (destroy)
1294                         (*destroy)(bo);
1295                 else
1296                         kfree(bo);
1297                 return -ENOMEM;
1298         }
1299
1300         num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1301         if (num_pages == 0) {
1302                 pr_err("Illegal buffer object size\n");
1303                 if (destroy)
1304                         (*destroy)(bo);
1305                 else
1306                         kfree(bo);
1307                 ttm_mem_global_free(mem_glob, acc_size);
1308                 return -EINVAL;
1309         }
1310         bo->destroy = destroy ? destroy : ttm_bo_default_destroy;
1311
1312         kref_init(&bo->kref);
1313         kref_init(&bo->list_kref);
1314         atomic_set(&bo->cpu_writers, 0);
1315         INIT_LIST_HEAD(&bo->lru);
1316         INIT_LIST_HEAD(&bo->ddestroy);
1317         INIT_LIST_HEAD(&bo->swap);
1318         INIT_LIST_HEAD(&bo->io_reserve_lru);
1319         mutex_init(&bo->wu_mutex);
1320         bo->bdev = bdev;
1321         bo->type = type;
1322         bo->num_pages = num_pages;
1323         bo->mem.size = num_pages << PAGE_SHIFT;
1324         bo->mem.mem_type = TTM_PL_SYSTEM;
1325         bo->mem.num_pages = bo->num_pages;
1326         bo->mem.mm_node = NULL;
1327         bo->mem.page_alignment = page_alignment;
1328         bo->mem.bus.io_reserved_vm = false;
1329         bo->mem.bus.io_reserved_count = 0;
1330         bo->moving = NULL;
1331         bo->mem.placement = (TTM_PL_FLAG_SYSTEM | TTM_PL_FLAG_CACHED);
1332         bo->acc_size = acc_size;
1333         bo->sg = sg;
1334         if (resv) {
1335                 bo->resv = resv;
1336                 reservation_object_assert_held(bo->resv);
1337         } else {
1338                 bo->resv = &bo->ttm_resv;
1339         }
1340         reservation_object_init(&bo->ttm_resv);
1341         atomic_inc(&bo->bdev->glob->bo_count);
1342         drm_vma_node_reset(&bo->vma_node);
1343
1344         /*
1345          * For ttm_bo_type_device buffers, allocate
1346          * address space from the device.
1347          */
1348         if (bo->type == ttm_bo_type_device ||
1349             bo->type == ttm_bo_type_sg)
1350                 ret = drm_vma_offset_add(&bdev->vma_manager, &bo->vma_node,
1351                                          bo->mem.num_pages);
1352
1353         /* passed reservation objects should already be locked,
1354          * since otherwise lockdep will be angered in radeon.
1355          */
1356         if (!resv) {
1357                 locked = reservation_object_trylock(bo->resv);
1358                 WARN_ON(!locked);
1359         }
1360
1361         if (likely(!ret))
1362                 ret = ttm_bo_validate(bo, placement, ctx);
1363
1364         if (unlikely(ret)) {
1365                 if (!resv)
1366                         ttm_bo_unreserve(bo);
1367
1368                 ttm_bo_put(bo);
1369                 return ret;
1370         }
1371
1372         if (resv && !(bo->mem.placement & TTM_PL_FLAG_NO_EVICT)) {
1373                 spin_lock(&bdev->glob->lru_lock);
1374                 ttm_bo_add_to_lru(bo);
1375                 spin_unlock(&bdev->glob->lru_lock);
1376         }
1377
1378         return ret;
1379 }
1380 EXPORT_SYMBOL(ttm_bo_init_reserved);
1381
1382 int ttm_bo_init(struct ttm_bo_device *bdev,
1383                 struct ttm_buffer_object *bo,
1384                 unsigned long size,
1385                 enum ttm_bo_type type,
1386                 struct ttm_placement *placement,
1387                 uint32_t page_alignment,
1388                 bool interruptible,
1389                 size_t acc_size,
1390                 struct sg_table *sg,
1391                 struct reservation_object *resv,
1392                 void (*destroy) (struct ttm_buffer_object *))
1393 {
1394         struct ttm_operation_ctx ctx = { interruptible, false };
1395         int ret;
1396
1397         ret = ttm_bo_init_reserved(bdev, bo, size, type, placement,
1398                                    page_alignment, &ctx, acc_size,
1399                                    sg, resv, destroy);
1400         if (ret)
1401                 return ret;
1402
1403         if (!resv)
1404                 ttm_bo_unreserve(bo);
1405
1406         return 0;
1407 }
1408 EXPORT_SYMBOL(ttm_bo_init);
1409
1410 size_t ttm_bo_acc_size(struct ttm_bo_device *bdev,
1411                        unsigned long bo_size,
1412                        unsigned struct_size)
1413 {
1414         unsigned npages = (PAGE_ALIGN(bo_size)) >> PAGE_SHIFT;
1415         size_t size = 0;
1416
1417         size += ttm_round_pot(struct_size);
1418         size += ttm_round_pot(npages * sizeof(void *));
1419         size += ttm_round_pot(sizeof(struct ttm_tt));
1420         return size;
1421 }
1422 EXPORT_SYMBOL(ttm_bo_acc_size);
1423
1424 size_t ttm_bo_dma_acc_size(struct ttm_bo_device *bdev,
1425                            unsigned long bo_size,
1426                            unsigned struct_size)
1427 {
1428         unsigned npages = (PAGE_ALIGN(bo_size)) >> PAGE_SHIFT;
1429         size_t size = 0;
1430
1431         size += ttm_round_pot(struct_size);
1432         size += ttm_round_pot(npages * (2*sizeof(void *) + sizeof(dma_addr_t)));
1433         size += ttm_round_pot(sizeof(struct ttm_dma_tt));
1434         return size;
1435 }
1436 EXPORT_SYMBOL(ttm_bo_dma_acc_size);
1437
1438 int ttm_bo_create(struct ttm_bo_device *bdev,
1439                         unsigned long size,
1440                         enum ttm_bo_type type,
1441                         struct ttm_placement *placement,
1442                         uint32_t page_alignment,
1443                         bool interruptible,
1444                         struct ttm_buffer_object **p_bo)
1445 {
1446         struct ttm_buffer_object *bo;
1447         size_t acc_size;
1448         int ret;
1449
1450         bo = kzalloc(sizeof(*bo), GFP_KERNEL);
1451         if (unlikely(bo == NULL))
1452                 return -ENOMEM;
1453
1454         acc_size = ttm_bo_acc_size(bdev, size, sizeof(struct ttm_buffer_object));
1455         ret = ttm_bo_init(bdev, bo, size, type, placement, page_alignment,
1456                           interruptible, acc_size,
1457                           NULL, NULL, NULL);
1458         if (likely(ret == 0))
1459                 *p_bo = bo;
1460
1461         return ret;
1462 }
1463 EXPORT_SYMBOL(ttm_bo_create);
1464
1465 static int ttm_bo_force_list_clean(struct ttm_bo_device *bdev,
1466                                    unsigned mem_type)
1467 {
1468         struct ttm_operation_ctx ctx = {
1469                 .interruptible = false,
1470                 .no_wait_gpu = false,
1471                 .flags = TTM_OPT_FLAG_FORCE_ALLOC
1472         };
1473         struct ttm_mem_type_manager *man = &bdev->man[mem_type];
1474         struct ttm_bo_global *glob = bdev->glob;
1475         struct dma_fence *fence;
1476         int ret;
1477         unsigned i;
1478
1479         /*
1480          * Can't use standard list traversal since we're unlocking.
1481          */
1482
1483         spin_lock(&glob->lru_lock);
1484         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
1485                 while (!list_empty(&man->lru[i])) {
1486                         spin_unlock(&glob->lru_lock);
1487                         ret = ttm_mem_evict_first(bdev, mem_type, NULL, &ctx,
1488                                                   NULL);
1489                         if (ret)
1490                                 return ret;
1491                         spin_lock(&glob->lru_lock);
1492                 }
1493         }
1494         spin_unlock(&glob->lru_lock);
1495
1496         spin_lock(&man->move_lock);
1497         fence = dma_fence_get(man->move);
1498         spin_unlock(&man->move_lock);
1499
1500         if (fence) {
1501                 ret = dma_fence_wait(fence, false);
1502                 dma_fence_put(fence);
1503                 if (ret)
1504                         return ret;
1505         }
1506
1507         return 0;
1508 }
1509
1510 int ttm_bo_clean_mm(struct ttm_bo_device *bdev, unsigned mem_type)
1511 {
1512         struct ttm_mem_type_manager *man;
1513         int ret = -EINVAL;
1514
1515         if (mem_type >= TTM_NUM_MEM_TYPES) {
1516                 pr_err("Illegal memory type %d\n", mem_type);
1517                 return ret;
1518         }
1519         man = &bdev->man[mem_type];
1520
1521         if (!man->has_type) {
1522                 pr_err("Trying to take down uninitialized memory manager type %u\n",
1523                        mem_type);
1524                 return ret;
1525         }
1526
1527         man->use_type = false;
1528         man->has_type = false;
1529
1530         ret = 0;
1531         if (mem_type > 0) {
1532                 ret = ttm_bo_force_list_clean(bdev, mem_type);
1533                 if (ret) {
1534                         pr_err("Cleanup eviction failed\n");
1535                         return ret;
1536                 }
1537
1538                 ret = (*man->func->takedown)(man);
1539         }
1540
1541         dma_fence_put(man->move);
1542         man->move = NULL;
1543
1544         return ret;
1545 }
1546 EXPORT_SYMBOL(ttm_bo_clean_mm);
1547
1548 int ttm_bo_evict_mm(struct ttm_bo_device *bdev, unsigned mem_type)
1549 {
1550         struct ttm_mem_type_manager *man = &bdev->man[mem_type];
1551
1552         if (mem_type == 0 || mem_type >= TTM_NUM_MEM_TYPES) {
1553                 pr_err("Illegal memory manager memory type %u\n", mem_type);
1554                 return -EINVAL;
1555         }
1556
1557         if (!man->has_type) {
1558                 pr_err("Memory type %u has not been initialized\n", mem_type);
1559                 return 0;
1560         }
1561
1562         return ttm_bo_force_list_clean(bdev, mem_type);
1563 }
1564 EXPORT_SYMBOL(ttm_bo_evict_mm);
1565
1566 int ttm_bo_init_mm(struct ttm_bo_device *bdev, unsigned type,
1567                         unsigned long p_size)
1568 {
1569         int ret;
1570         struct ttm_mem_type_manager *man;
1571         unsigned i;
1572
1573         BUG_ON(type >= TTM_NUM_MEM_TYPES);
1574         man = &bdev->man[type];
1575         BUG_ON(man->has_type);
1576         man->io_reserve_fastpath = true;
1577         man->use_io_reserve_lru = false;
1578         mutex_init(&man->io_reserve_mutex);
1579         spin_lock_init(&man->move_lock);
1580         INIT_LIST_HEAD(&man->io_reserve_lru);
1581
1582         ret = bdev->driver->init_mem_type(bdev, type, man);
1583         if (ret)
1584                 return ret;
1585         man->bdev = bdev;
1586
1587         if (type != TTM_PL_SYSTEM) {
1588                 ret = (*man->func->init)(man, p_size);
1589                 if (ret)
1590                         return ret;
1591         }
1592         man->has_type = true;
1593         man->use_type = true;
1594         man->size = p_size;
1595
1596         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
1597                 INIT_LIST_HEAD(&man->lru[i]);
1598         man->move = NULL;
1599
1600         return 0;
1601 }
1602 EXPORT_SYMBOL(ttm_bo_init_mm);
1603
1604 static void ttm_bo_global_kobj_release(struct kobject *kobj)
1605 {
1606         struct ttm_bo_global *glob =
1607                 container_of(kobj, struct ttm_bo_global, kobj);
1608
1609         __free_page(glob->dummy_read_page);
1610 }
1611
1612 static void ttm_bo_global_release(void)
1613 {
1614         struct ttm_bo_global *glob = &ttm_bo_glob;
1615
1616         mutex_lock(&ttm_global_mutex);
1617         if (--ttm_bo_glob_use_count > 0)
1618                 goto out;
1619
1620         kobject_del(&glob->kobj);
1621         kobject_put(&glob->kobj);
1622         ttm_mem_global_release(&ttm_mem_glob);
1623         memset(glob, 0, sizeof(*glob));
1624 out:
1625         mutex_unlock(&ttm_global_mutex);
1626 }
1627
1628 static int ttm_bo_global_init(void)
1629 {
1630         struct ttm_bo_global *glob = &ttm_bo_glob;
1631         int ret = 0;
1632         unsigned i;
1633
1634         mutex_lock(&ttm_global_mutex);
1635         if (++ttm_bo_glob_use_count > 1)
1636                 goto out;
1637
1638         ret = ttm_mem_global_init(&ttm_mem_glob);
1639         if (ret)
1640                 goto out;
1641
1642         spin_lock_init(&glob->lru_lock);
1643         glob->mem_glob = &ttm_mem_glob;
1644         glob->mem_glob->bo_glob = glob;
1645         glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32);
1646
1647         if (unlikely(glob->dummy_read_page == NULL)) {
1648                 ret = -ENOMEM;
1649                 goto out;
1650         }
1651
1652         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
1653                 INIT_LIST_HEAD(&glob->swap_lru[i]);
1654         INIT_LIST_HEAD(&glob->device_list);
1655         atomic_set(&glob->bo_count, 0);
1656
1657         ret = kobject_init_and_add(
1658                 &glob->kobj, &ttm_bo_glob_kobj_type, ttm_get_kobj(), "buffer_objects");
1659         if (unlikely(ret != 0))
1660                 kobject_put(&glob->kobj);
1661 out:
1662         mutex_unlock(&ttm_global_mutex);
1663         return ret;
1664 }
1665
1666 int ttm_bo_device_release(struct ttm_bo_device *bdev)
1667 {
1668         int ret = 0;
1669         unsigned i = TTM_NUM_MEM_TYPES;
1670         struct ttm_mem_type_manager *man;
1671         struct ttm_bo_global *glob = bdev->glob;
1672
1673         while (i--) {
1674                 man = &bdev->man[i];
1675                 if (man->has_type) {
1676                         man->use_type = false;
1677                         if ((i != TTM_PL_SYSTEM) && ttm_bo_clean_mm(bdev, i)) {
1678                                 ret = -EBUSY;
1679                                 pr_err("DRM memory manager type %d is not clean\n",
1680                                        i);
1681                         }
1682                         man->has_type = false;
1683                 }
1684         }
1685
1686         mutex_lock(&ttm_global_mutex);
1687         list_del(&bdev->device_list);
1688         mutex_unlock(&ttm_global_mutex);
1689
1690         cancel_delayed_work_sync(&bdev->wq);
1691
1692         if (ttm_bo_delayed_delete(bdev, true))
1693                 pr_debug("Delayed destroy list was clean\n");
1694
1695         spin_lock(&glob->lru_lock);
1696         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
1697                 if (list_empty(&bdev->man[0].lru[0]))
1698                         pr_debug("Swap list %d was clean\n", i);
1699         spin_unlock(&glob->lru_lock);
1700
1701         drm_vma_offset_manager_destroy(&bdev->vma_manager);
1702
1703         if (!ret)
1704                 ttm_bo_global_release();
1705
1706         return ret;
1707 }
1708 EXPORT_SYMBOL(ttm_bo_device_release);
1709
1710 int ttm_bo_device_init(struct ttm_bo_device *bdev,
1711                        struct ttm_bo_driver *driver,
1712                        struct address_space *mapping,
1713                        bool need_dma32)
1714 {
1715         struct ttm_bo_global *glob = &ttm_bo_glob;
1716         int ret;
1717
1718         ret = ttm_bo_global_init();
1719         if (ret)
1720                 return ret;
1721
1722         bdev->driver = driver;
1723
1724         memset(bdev->man, 0, sizeof(bdev->man));
1725
1726         /*
1727          * Initialize the system memory buffer type.
1728          * Other types need to be driver / IOCTL initialized.
1729          */
1730         ret = ttm_bo_init_mm(bdev, TTM_PL_SYSTEM, 0);
1731         if (unlikely(ret != 0))
1732                 goto out_no_sys;
1733
1734         drm_vma_offset_manager_init(&bdev->vma_manager,
1735                                     DRM_FILE_PAGE_OFFSET_START,
1736                                     DRM_FILE_PAGE_OFFSET_SIZE);
1737         INIT_DELAYED_WORK(&bdev->wq, ttm_bo_delayed_workqueue);
1738         INIT_LIST_HEAD(&bdev->ddestroy);
1739         bdev->dev_mapping = mapping;
1740         bdev->glob = glob;
1741         bdev->need_dma32 = need_dma32;
1742         mutex_lock(&ttm_global_mutex);
1743         list_add_tail(&bdev->device_list, &glob->device_list);
1744         mutex_unlock(&ttm_global_mutex);
1745         bdev->vm_ops = &ttm_bo_vm_ops;
1746
1747         return 0;
1748 out_no_sys:
1749         ttm_bo_global_release();
1750         return ret;
1751 }
1752 EXPORT_SYMBOL(ttm_bo_device_init);
1753
1754 /*
1755  * buffer object vm functions.
1756  */
1757
1758 bool ttm_mem_reg_is_pci(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem)
1759 {
1760         struct ttm_mem_type_manager *man = &bdev->man[mem->mem_type];
1761
1762         if (!(man->flags & TTM_MEMTYPE_FLAG_FIXED)) {
1763                 if (mem->mem_type == TTM_PL_SYSTEM)
1764                         return false;
1765
1766                 if (man->flags & TTM_MEMTYPE_FLAG_CMA)
1767                         return false;
1768
1769                 if (mem->placement & TTM_PL_FLAG_CACHED)
1770                         return false;
1771         }
1772         return true;
1773 }
1774
1775 void ttm_bo_unmap_virtual_locked(struct ttm_buffer_object *bo)
1776 {
1777         struct ttm_bo_device *bdev = bo->bdev;
1778
1779         drm_vma_node_unmap(&bo->vma_node, bdev->dev_mapping);
1780         ttm_mem_io_free_vm(bo);
1781 }
1782
1783 void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo)
1784 {
1785         struct ttm_bo_device *bdev = bo->bdev;
1786         struct ttm_mem_type_manager *man = &bdev->man[bo->mem.mem_type];
1787
1788         ttm_mem_io_lock(man, false);
1789         ttm_bo_unmap_virtual_locked(bo);
1790         ttm_mem_io_unlock(man);
1791 }
1792
1793
1794 EXPORT_SYMBOL(ttm_bo_unmap_virtual);
1795
1796 int ttm_bo_wait(struct ttm_buffer_object *bo,
1797                 bool interruptible, bool no_wait)
1798 {
1799         long timeout = 15 * HZ;
1800
1801         if (no_wait) {
1802                 if (reservation_object_test_signaled_rcu(bo->resv, true))
1803                         return 0;
1804                 else
1805                         return -EBUSY;
1806         }
1807
1808         timeout = reservation_object_wait_timeout_rcu(bo->resv, true,
1809                                                       interruptible, timeout);
1810         if (timeout < 0)
1811                 return timeout;
1812
1813         if (timeout == 0)
1814                 return -EBUSY;
1815
1816         reservation_object_add_excl_fence(bo->resv, NULL);
1817         return 0;
1818 }
1819 EXPORT_SYMBOL(ttm_bo_wait);
1820
1821 int ttm_bo_synccpu_write_grab(struct ttm_buffer_object *bo, bool no_wait)
1822 {
1823         int ret = 0;
1824
1825         /*
1826          * Using ttm_bo_reserve makes sure the lru lists are updated.
1827          */
1828
1829         ret = ttm_bo_reserve(bo, true, no_wait, NULL);
1830         if (unlikely(ret != 0))
1831                 return ret;
1832         ret = ttm_bo_wait(bo, true, no_wait);
1833         if (likely(ret == 0))
1834                 atomic_inc(&bo->cpu_writers);
1835         ttm_bo_unreserve(bo);
1836         return ret;
1837 }
1838 EXPORT_SYMBOL(ttm_bo_synccpu_write_grab);
1839
1840 void ttm_bo_synccpu_write_release(struct ttm_buffer_object *bo)
1841 {
1842         atomic_dec(&bo->cpu_writers);
1843 }
1844 EXPORT_SYMBOL(ttm_bo_synccpu_write_release);
1845
1846 /**
1847  * A buffer object shrink method that tries to swap out the first
1848  * buffer object on the bo_global::swap_lru list.
1849  */
1850 int ttm_bo_swapout(struct ttm_bo_global *glob, struct ttm_operation_ctx *ctx)
1851 {
1852         struct ttm_buffer_object *bo;
1853         int ret = -EBUSY;
1854         bool locked;
1855         unsigned i;
1856
1857         spin_lock(&glob->lru_lock);
1858         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
1859                 list_for_each_entry(bo, &glob->swap_lru[i], swap) {
1860                         if (ttm_bo_evict_swapout_allowable(bo, ctx, &locked,
1861                                                            NULL)) {
1862                                 ret = 0;
1863                                 break;
1864                         }
1865                 }
1866                 if (!ret)
1867                         break;
1868         }
1869
1870         if (ret) {
1871                 spin_unlock(&glob->lru_lock);
1872                 return ret;
1873         }
1874
1875         kref_get(&bo->list_kref);
1876
1877         if (!list_empty(&bo->ddestroy)) {
1878                 ret = ttm_bo_cleanup_refs(bo, false, false, locked);
1879                 kref_put(&bo->list_kref, ttm_bo_release_list);
1880                 return ret;
1881         }
1882
1883         ttm_bo_del_from_lru(bo);
1884         spin_unlock(&glob->lru_lock);
1885
1886         /**
1887          * Move to system cached
1888          */
1889
1890         if (bo->mem.mem_type != TTM_PL_SYSTEM ||
1891             bo->ttm->caching_state != tt_cached) {
1892                 struct ttm_operation_ctx ctx = { false, false };
1893                 struct ttm_mem_reg evict_mem;
1894
1895                 evict_mem = bo->mem;
1896                 evict_mem.mm_node = NULL;
1897                 evict_mem.placement = TTM_PL_FLAG_SYSTEM | TTM_PL_FLAG_CACHED;
1898                 evict_mem.mem_type = TTM_PL_SYSTEM;
1899
1900                 ret = ttm_bo_handle_move_mem(bo, &evict_mem, true, &ctx);
1901                 if (unlikely(ret != 0))
1902                         goto out;
1903         }
1904
1905         /**
1906          * Make sure BO is idle.
1907          */
1908
1909         ret = ttm_bo_wait(bo, false, false);
1910         if (unlikely(ret != 0))
1911                 goto out;
1912
1913         ttm_bo_unmap_virtual(bo);
1914
1915         /**
1916          * Swap out. Buffer will be swapped in again as soon as
1917          * anyone tries to access a ttm page.
1918          */
1919
1920         if (bo->bdev->driver->swap_notify)
1921                 bo->bdev->driver->swap_notify(bo);
1922
1923         ret = ttm_tt_swapout(bo->ttm, bo->persistent_swap_storage);
1924 out:
1925
1926         /**
1927          *
1928          * Unreserve without putting on LRU to avoid swapping out an
1929          * already swapped buffer.
1930          */
1931         if (locked)
1932                 reservation_object_unlock(bo->resv);
1933         kref_put(&bo->list_kref, ttm_bo_release_list);
1934         return ret;
1935 }
1936 EXPORT_SYMBOL(ttm_bo_swapout);
1937
1938 void ttm_bo_swapout_all(struct ttm_bo_device *bdev)
1939 {
1940         struct ttm_operation_ctx ctx = {
1941                 .interruptible = false,
1942                 .no_wait_gpu = false
1943         };
1944
1945         while (ttm_bo_swapout(bdev->glob, &ctx) == 0)
1946                 ;
1947 }
1948 EXPORT_SYMBOL(ttm_bo_swapout_all);
1949
1950 /**
1951  * ttm_bo_wait_unreserved - interruptible wait for a buffer object to become
1952  * unreserved
1953  *
1954  * @bo: Pointer to buffer
1955  */
1956 int ttm_bo_wait_unreserved(struct ttm_buffer_object *bo)
1957 {
1958         int ret;
1959
1960         /*
1961          * In the absense of a wait_unlocked API,
1962          * Use the bo::wu_mutex to avoid triggering livelocks due to
1963          * concurrent use of this function. Note that this use of
1964          * bo::wu_mutex can go away if we change locking order to
1965          * mmap_sem -> bo::reserve.
1966          */
1967         ret = mutex_lock_interruptible(&bo->wu_mutex);
1968         if (unlikely(ret != 0))
1969                 return -ERESTARTSYS;
1970         if (!ww_mutex_is_locked(&bo->resv->lock))
1971                 goto out_unlock;
1972         ret = reservation_object_lock_interruptible(bo->resv, NULL);
1973         if (ret == -EINTR)
1974                 ret = -ERESTARTSYS;
1975         if (unlikely(ret != 0))
1976                 goto out_unlock;
1977         reservation_object_unlock(bo->resv);
1978
1979 out_unlock:
1980         mutex_unlock(&bo->wu_mutex);
1981         return ret;
1982 }