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_bo_driver.h>
  35 #include <drm/ttm/ttm_placement.h>
  36 #include <linux/jiffies.h>
  37 #include <linux/slab.h>
  38 #include <linux/sched.h>
  39 #include <linux/mm.h>
  40 #include <linux/file.h>
  41 #include <linux/module.h>
  42 #include <linux/atomic.h>
  43 #include <linux/dma-resv.h>
  44
  45 #include "ttm_module.h"
  46
  47 /* default destructor */
  48 static void ttm_bo_default_destroy(struct ttm_buffer_object *bo)
  49 {
  50         kfree(bo);
  51 }
  52
  53 static void ttm_bo_mem_space_debug(struct ttm_buffer_object *bo,
  54                                         struct ttm_placement *placement)
  55 {
  56         struct drm_printer p = drm_debug_printer(TTM_PFX);
  57         struct ttm_resource_manager *man;
  58         int i, mem_type;
  59
  60         drm_printf(&p, "No space for %p (%lu pages, %zuK, %zuM)\n",
  61                    bo, bo->resource->num_pages, bo->base.size >> 10,
  62                    bo->base.size >> 20);
  63         for (i = 0; i < placement->num_placement; i++) {
  64                 mem_type = placement->placement[i].mem_type;
  65                 drm_printf(&p, "  placement[%d]=0x%08X (%d)\n",
  66                            i, placement->placement[i].flags, mem_type);
  67                 man = ttm_manager_type(bo->bdev, mem_type);
  68                 ttm_resource_manager_debug(man, &p);
  69         }
  70 }
  71
  72 static inline void ttm_bo_move_to_pinned(struct ttm_buffer_object *bo)
  73 {
  74         struct ttm_device *bdev = bo->bdev;
  75
  76         list_move_tail(&bo->lru, &bdev->pinned);
  77
  78         if (bdev->funcs->del_from_lru_notify)
  79                 bdev->funcs->del_from_lru_notify(bo);
  80 }
  81
  82 static inline void ttm_bo_del_from_lru(struct ttm_buffer_object *bo)
  83 {
  84         struct ttm_device *bdev = bo->bdev;
  85
  86         list_del_init(&bo->lru);
  87
  88         if (bdev->funcs->del_from_lru_notify)
  89                 bdev->funcs->del_from_lru_notify(bo);
  90 }
  91
  92 static void ttm_bo_bulk_move_set_pos(struct ttm_lru_bulk_move_pos *pos,
  93                                      struct ttm_buffer_object *bo)
  94 {
  95         if (!pos->first)
  96                 pos->first = bo;
  97         pos->last = bo;
  98 }
  99
 100 void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo,
 101                              struct ttm_resource *mem,
 102                              struct ttm_lru_bulk_move *bulk)
 103 {
 104         struct ttm_device *bdev = bo->bdev;
 105         struct ttm_resource_manager *man;
 106
 107         if (!bo->deleted)
 108                 dma_resv_assert_held(bo->base.resv);
 109
 110         if (bo->pin_count) {
 111                 ttm_bo_move_to_pinned(bo);
 112                 return;
 113         }
 114
 115         if (!mem)
 116                 return;
 117
 118         man = ttm_manager_type(bdev, mem->mem_type);
 119         list_move_tail(&bo->lru, &man->lru[bo->priority]);
 120
 121         if (bdev->funcs->del_from_lru_notify)
 122                 bdev->funcs->del_from_lru_notify(bo);
 123
 124         if (bulk && !bo->pin_count) {
 125                 switch (bo->resource->mem_type) {
 126                 case TTM_PL_TT:
 127                         ttm_bo_bulk_move_set_pos(&bulk->tt[bo->priority], bo);
 128                         break;
 129
 130                 case TTM_PL_VRAM:
 131                         ttm_bo_bulk_move_set_pos(&bulk->vram[bo->priority], bo);
 132                         break;
 133                 }
 134         }
 135 }
 136 EXPORT_SYMBOL(ttm_bo_move_to_lru_tail);
 137
 138 void ttm_bo_bulk_move_lru_tail(struct ttm_lru_bulk_move *bulk)
 139 {
 140         unsigned i;
 141
 142         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
 143                 struct ttm_lru_bulk_move_pos *pos = &bulk->tt[i];
 144                 struct ttm_resource_manager *man;
 145
 146                 if (!pos->first)
 147                         continue;
 148
 149                 dma_resv_assert_held(pos->first->base.resv);
 150                 dma_resv_assert_held(pos->last->base.resv);
 151
 152                 man = ttm_manager_type(pos->first->bdev, TTM_PL_TT);
 153                 list_bulk_move_tail(&man->lru[i], &pos->first->lru,
 154                                     &pos->last->lru);
 155         }
 156
 157         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
 158                 struct ttm_lru_bulk_move_pos *pos = &bulk->vram[i];
 159                 struct ttm_resource_manager *man;
 160
 161                 if (!pos->first)
 162                         continue;
 163
 164                 dma_resv_assert_held(pos->first->base.resv);
 165                 dma_resv_assert_held(pos->last->base.resv);
 166
 167                 man = ttm_manager_type(pos->first->bdev, TTM_PL_VRAM);
 168                 list_bulk_move_tail(&man->lru[i], &pos->first->lru,
 169                                     &pos->last->lru);
 170         }
 171 }
 172 EXPORT_SYMBOL(ttm_bo_bulk_move_lru_tail);
 173
 174 static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo,
 175                                   struct ttm_resource *mem, bool evict,
 176                                   struct ttm_operation_ctx *ctx,
 177                                   struct ttm_place *hop)
 178 {
 179         struct ttm_resource_manager *old_man, *new_man;
 180         struct ttm_device *bdev = bo->bdev;
 181         int ret;
 182
 183         old_man = ttm_manager_type(bdev, bo->resource->mem_type);
 184         new_man = ttm_manager_type(bdev, mem->mem_type);
 185
 186         ttm_bo_unmap_virtual(bo);
 187
 188         /*
 189          * Create and bind a ttm if required.
 190          */
 191
 192         if (new_man->use_tt) {
 193                 /* Zero init the new TTM structure if the old location should
 194                  * have used one as well.
 195                  */
 196                 ret = ttm_tt_create(bo, old_man->use_tt);
 197                 if (ret)
 198                         goto out_err;
 199
 200                 if (mem->mem_type != TTM_PL_SYSTEM) {
 201                         ret = ttm_tt_populate(bo->bdev, bo->ttm, ctx);
 202                         if (ret)
 203                                 goto out_err;
 204                 }
 205         }
 206
 207         ret = bdev->funcs->move(bo, evict, ctx, mem, hop);
 208         if (ret) {
 209                 if (ret == -EMULTIHOP)
 210                         return ret;
 211                 goto out_err;
 212         }
 213
 214         ctx->bytes_moved += bo->base.size;
 215         return 0;
 216
 217 out_err:
 218         new_man = ttm_manager_type(bdev, bo->resource->mem_type);
 219         if (!new_man->use_tt)
 220                 ttm_bo_tt_destroy(bo);
 221
 222         return ret;
 223 }
 224
 225 /*
 226  * Call bo::reserved.
 227  * Will release GPU memory type usage on destruction.
 228  * This is the place to put in driver specific hooks to release
 229  * driver private resources.
 230  * Will release the bo::reserved lock.
 231  */
 232
 233 static void ttm_bo_cleanup_memtype_use(struct ttm_buffer_object *bo)
 234 {
 235         if (bo->bdev->funcs->delete_mem_notify)
 236                 bo->bdev->funcs->delete_mem_notify(bo);
 237
 238         ttm_bo_tt_destroy(bo);
 239         ttm_resource_free(bo, &bo->resource);
 240 }
 241
 242 static int ttm_bo_individualize_resv(struct ttm_buffer_object *bo)
 243 {
 244         int r;
 245
 246         if (bo->base.resv == &bo->base._resv)
 247                 return 0;
 248
 249         BUG_ON(!dma_resv_trylock(&bo->base._resv));
 250
 251         r = dma_resv_copy_fences(&bo->base._resv, bo->base.resv);
 252         dma_resv_unlock(&bo->base._resv);
 253         if (r)
 254                 return r;
 255
 256         if (bo->type != ttm_bo_type_sg) {
 257                 /* This works because the BO is about to be destroyed and nobody
 258                  * reference it any more. The only tricky case is the trylock on
 259                  * the resv object while holding the lru_lock.
 260                  */
 261                 spin_lock(&bo->bdev->lru_lock);
 262                 bo->base.resv = &bo->base._resv;
 263                 spin_unlock(&bo->bdev->lru_lock);
 264         }
 265
 266         return r;
 267 }
 268
 269 static void ttm_bo_flush_all_fences(struct ttm_buffer_object *bo)
 270 {
 271         struct dma_resv *resv = &bo->base._resv;
 272         struct dma_resv_iter cursor;
 273         struct dma_fence *fence;
 274
 275         dma_resv_iter_begin(&cursor, resv, true);
 276         dma_resv_for_each_fence_unlocked(&cursor, fence) {
 277                 if (!fence->ops->signaled)
 278                         dma_fence_enable_sw_signaling(fence);
 279         }
 280         dma_resv_iter_end(&cursor);
 281 }
 282
 283 /**
 284  * ttm_bo_cleanup_refs
 285  * If bo idle, remove from lru lists, and unref.
 286  * If not idle, block if possible.
 287  *
 288  * Must be called with lru_lock and reservation held, this function
 289  * will drop the lru lock and optionally the reservation lock before returning.
 290  *
 291  * @bo:                    The buffer object to clean-up
 292  * @interruptible:         Any sleeps should occur interruptibly.
 293  * @no_wait_gpu:           Never wait for gpu. Return -EBUSY instead.
 294  * @unlock_resv:           Unlock the reservation lock as well.
 295  */
 296
 297 static int ttm_bo_cleanup_refs(struct ttm_buffer_object *bo,
 298                                bool interruptible, bool no_wait_gpu,
 299                                bool unlock_resv)
 300 {
 301         struct dma_resv *resv = &bo->base._resv;
 302         int ret;
 303
 304         if (dma_resv_test_signaled(resv, true))
 305                 ret = 0;
 306         else
 307                 ret = -EBUSY;
 308
 309         if (ret && !no_wait_gpu) {
 310                 long lret;
 311
 312                 if (unlock_resv)
 313                         dma_resv_unlock(bo->base.resv);
 314                 spin_unlock(&bo->bdev->lru_lock);
 315
 316                 lret = dma_resv_wait_timeout(resv, true, interruptible,
 317                                              30 * HZ);
 318
 319                 if (lret < 0)
 320                         return lret;
 321                 else if (lret == 0)
 322                         return -EBUSY;
 323
 324                 spin_lock(&bo->bdev->lru_lock);
 325                 if (unlock_resv && !dma_resv_trylock(bo->base.resv)) {
 326                         /*
 327                          * We raced, and lost, someone else holds the reservation now,
 328                          * and is probably busy in ttm_bo_cleanup_memtype_use.
 329                          *
 330                          * Even if it's not the case, because we finished waiting any
 331                          * delayed destruction would succeed, so just return success
 332                          * here.
 333                          */
 334                         spin_unlock(&bo->bdev->lru_lock);
 335                         return 0;
 336                 }
 337                 ret = 0;
 338         }
 339
 340         if (ret || unlikely(list_empty(&bo->ddestroy))) {
 341                 if (unlock_resv)
 342                         dma_resv_unlock(bo->base.resv);
 343                 spin_unlock(&bo->bdev->lru_lock);
 344                 return ret;
 345         }
 346
 347         ttm_bo_move_to_pinned(bo);
 348         list_del_init(&bo->ddestroy);
 349         spin_unlock(&bo->bdev->lru_lock);
 350         ttm_bo_cleanup_memtype_use(bo);
 351
 352         if (unlock_resv)
 353                 dma_resv_unlock(bo->base.resv);
 354
 355         ttm_bo_put(bo);
 356
 357         return 0;
 358 }
 359
 360 /*
 361  * Traverse the delayed list, and call ttm_bo_cleanup_refs on all
 362  * encountered buffers.
 363  */
 364 bool ttm_bo_delayed_delete(struct ttm_device *bdev, bool remove_all)
 365 {
 366         struct list_head removed;
 367         bool empty;
 368
 369         INIT_LIST_HEAD(&removed);
 370
 371         spin_lock(&bdev->lru_lock);
 372         while (!list_empty(&bdev->ddestroy)) {
 373                 struct ttm_buffer_object *bo;
 374
 375                 bo = list_first_entry(&bdev->ddestroy, struct ttm_buffer_object,
 376                                       ddestroy);
 377                 list_move_tail(&bo->ddestroy, &removed);
 378                 if (!ttm_bo_get_unless_zero(bo))
 379                         continue;
 380
 381                 if (remove_all || bo->base.resv != &bo->base._resv) {
 382                         spin_unlock(&bdev->lru_lock);
 383                         dma_resv_lock(bo->base.resv, NULL);
 384
 385                         spin_lock(&bdev->lru_lock);
 386                         ttm_bo_cleanup_refs(bo, false, !remove_all, true);
 387
 388                 } else if (dma_resv_trylock(bo->base.resv)) {
 389                         ttm_bo_cleanup_refs(bo, false, !remove_all, true);
 390                 } else {
 391                         spin_unlock(&bdev->lru_lock);
 392                 }
 393
 394                 ttm_bo_put(bo);
 395                 spin_lock(&bdev->lru_lock);
 396         }
 397         list_splice_tail(&removed, &bdev->ddestroy);
 398         empty = list_empty(&bdev->ddestroy);
 399         spin_unlock(&bdev->lru_lock);
 400
 401         return empty;
 402 }
 403
 404 static void ttm_bo_release(struct kref *kref)
 405 {
 406         struct ttm_buffer_object *bo =
 407             container_of(kref, struct ttm_buffer_object, kref);
 408         struct ttm_device *bdev = bo->bdev;
 409         int ret;
 410
 411         WARN_ON_ONCE(bo->pin_count);
 412
 413         if (!bo->deleted) {
 414                 ret = ttm_bo_individualize_resv(bo);
 415                 if (ret) {
 416                         /* Last resort, if we fail to allocate memory for the
 417                          * fences block for the BO to become idle
 418                          */
 419                         dma_resv_wait_timeout(bo->base.resv, true, false,
 420                                               30 * HZ);
 421                 }
 422
 423                 if (bo->bdev->funcs->release_notify)
 424                         bo->bdev->funcs->release_notify(bo);
 425
 426                 drm_vma_offset_remove(bdev->vma_manager, &bo->base.vma_node);
 427                 ttm_mem_io_free(bdev, bo->resource);
 428         }
 429
 430         if (!dma_resv_test_signaled(bo->base.resv, true) ||
 431             !dma_resv_trylock(bo->base.resv)) {
 432                 /* The BO is not idle, resurrect it for delayed destroy */
 433                 ttm_bo_flush_all_fences(bo);
 434                 bo->deleted = true;
 435
 436                 spin_lock(&bo->bdev->lru_lock);
 437
 438                 /*
 439                  * Make pinned bos immediately available to
 440                  * shrinkers, now that they are queued for
 441                  * destruction.
 442                  *
 443                  * FIXME: QXL is triggering this. Can be removed when the
 444                  * driver is fixed.
 445                  */
 446                 if (bo->pin_count) {
 447                         bo->pin_count = 0;
 448                         ttm_bo_move_to_lru_tail(bo, bo->resource, NULL);
 449                 }
 450
 451                 kref_init(&bo->kref);
 452                 list_add_tail(&bo->ddestroy, &bdev->ddestroy);
 453                 spin_unlock(&bo->bdev->lru_lock);
 454
 455                 schedule_delayed_work(&bdev->wq,
 456                                       ((HZ / 100) < 1) ? 1 : HZ / 100);
 457                 return;
 458         }
 459
 460         spin_lock(&bo->bdev->lru_lock);
 461         ttm_bo_del_from_lru(bo);
 462         list_del(&bo->ddestroy);
 463         spin_unlock(&bo->bdev->lru_lock);
 464
 465         ttm_bo_cleanup_memtype_use(bo);
 466         dma_resv_unlock(bo->base.resv);
 467
 468         atomic_dec(&ttm_glob.bo_count);
 469         dma_fence_put(bo->moving);
 470         bo->destroy(bo);
 471 }
 472
 473 void ttm_bo_put(struct ttm_buffer_object *bo)
 474 {
 475         kref_put(&bo->kref, ttm_bo_release);
 476 }
 477 EXPORT_SYMBOL(ttm_bo_put);
 478
 479 int ttm_bo_lock_delayed_workqueue(struct ttm_device *bdev)
 480 {
 481         return cancel_delayed_work_sync(&bdev->wq);
 482 }
 483 EXPORT_SYMBOL(ttm_bo_lock_delayed_workqueue);
 484
 485 void ttm_bo_unlock_delayed_workqueue(struct ttm_device *bdev, int resched)
 486 {
 487         if (resched)
 488                 schedule_delayed_work(&bdev->wq,
 489                                       ((HZ / 100) < 1) ? 1 : HZ / 100);
 490 }
 491 EXPORT_SYMBOL(ttm_bo_unlock_delayed_workqueue);
 492
 493 static int ttm_bo_bounce_temp_buffer(struct ttm_buffer_object *bo,
 494                                      struct ttm_resource **mem,
 495                                      struct ttm_operation_ctx *ctx,
 496                                      struct ttm_place *hop)
 497 {
 498         struct ttm_placement hop_placement;
 499         struct ttm_resource *hop_mem;
 500         int ret;
 501
 502         hop_placement.num_placement = hop_placement.num_busy_placement = 1;
 503         hop_placement.placement = hop_placement.busy_placement = hop;
 504
 505         /* find space in the bounce domain */
 506         ret = ttm_bo_mem_space(bo, &hop_placement, &hop_mem, ctx);
 507         if (ret)
 508                 return ret;
 509         /* move to the bounce domain */
 510         ret = ttm_bo_handle_move_mem(bo, hop_mem, false, ctx, NULL);
 511         if (ret) {
 512                 ttm_resource_free(bo, &hop_mem);
 513                 return ret;
 514         }
 515         return 0;
 516 }
 517
 518 static int ttm_bo_evict(struct ttm_buffer_object *bo,
 519                         struct ttm_operation_ctx *ctx)
 520 {
 521         struct ttm_device *bdev = bo->bdev;
 522         struct ttm_resource *evict_mem;
 523         struct ttm_placement placement;
 524         struct ttm_place hop;
 525         int ret = 0;
 526
 527         memset(&hop, 0, sizeof(hop));
 528
 529         dma_resv_assert_held(bo->base.resv);
 530
 531         placement.num_placement = 0;
 532         placement.num_busy_placement = 0;
 533         bdev->funcs->evict_flags(bo, &placement);
 534
 535         if (!placement.num_placement && !placement.num_busy_placement) {
 536                 ret = ttm_bo_wait(bo, true, false);
 537                 if (ret)
 538                         return ret;
 539
 540                 /*
 541                  * Since we've already synced, this frees backing store
 542                  * immediately.
 543                  */
 544                 return ttm_bo_pipeline_gutting(bo);
 545         }
 546
 547         ret = ttm_bo_mem_space(bo, &placement, &evict_mem, ctx);
 548         if (ret) {
 549                 if (ret != -ERESTARTSYS) {
 550                         pr_err("Failed to find memory space for buffer 0x%p eviction\n",
 551                                bo);
 552                         ttm_bo_mem_space_debug(bo, &placement);
 553                 }
 554                 goto out;
 555         }
 556
 557 bounce:
 558         ret = ttm_bo_handle_move_mem(bo, evict_mem, true, ctx, &hop);
 559         if (ret == -EMULTIHOP) {
 560                 ret = ttm_bo_bounce_temp_buffer(bo, &evict_mem, ctx, &hop);
 561                 if (ret) {
 562                         pr_err("Buffer eviction failed\n");
 563                         ttm_resource_free(bo, &evict_mem);
 564                         goto out;
 565                 }
 566                 /* try and move to final place now. */
 567                 goto bounce;
 568         }
 569 out:
 570         return ret;
 571 }
 572
 573 bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
 574                               const struct ttm_place *place)
 575 {
 576         dma_resv_assert_held(bo->base.resv);
 577         if (bo->resource->mem_type == TTM_PL_SYSTEM)
 578                 return true;
 579
 580         /* Don't evict this BO if it's outside of the
 581          * requested placement range
 582          */
 583         if (place->fpfn >= (bo->resource->start + bo->resource->num_pages) ||
 584             (place->lpfn && place->lpfn <= bo->resource->start))
 585                 return false;
 586
 587         return true;
 588 }
 589 EXPORT_SYMBOL(ttm_bo_eviction_valuable);
 590
 591 /*
 592  * Check the target bo is allowable to be evicted or swapout, including cases:
 593  *
 594  * a. if share same reservation object with ctx->resv, have assumption
 595  * reservation objects should already be locked, so not lock again and
 596  * return true directly when either the opreation allow_reserved_eviction
 597  * or the target bo already is in delayed free list;
 598  *
 599  * b. Otherwise, trylock it.
 600  */
 601 static bool ttm_bo_evict_swapout_allowable(struct ttm_buffer_object *bo,
 602                                            struct ttm_operation_ctx *ctx,
 603                                            const struct ttm_place *place,
 604                                            bool *locked, bool *busy)
 605 {
 606         bool ret = false;
 607
 608         if (bo->base.resv == ctx->resv) {
 609                 dma_resv_assert_held(bo->base.resv);
 610                 if (ctx->allow_res_evict)
 611                         ret = true;
 612                 *locked = false;
 613                 if (busy)
 614                         *busy = false;
 615         } else {
 616                 ret = dma_resv_trylock(bo->base.resv);
 617                 *locked = ret;
 618                 if (busy)
 619                         *busy = !ret;
 620         }
 621
 622         if (ret && place && (bo->resource->mem_type != place->mem_type ||
 623                 !bo->bdev->funcs->eviction_valuable(bo, place))) {
 624                 ret = false;
 625                 if (*locked) {
 626                         dma_resv_unlock(bo->base.resv);
 627                         *locked = false;
 628                 }
 629         }
 630
 631         return ret;
 632 }
 633
 634 /**
 635  * ttm_mem_evict_wait_busy - wait for a busy BO to become available
 636  *
 637  * @busy_bo: BO which couldn't be locked with trylock
 638  * @ctx: operation context
 639  * @ticket: acquire ticket
 640  *
 641  * Try to lock a busy buffer object to avoid failing eviction.
 642  */
 643 static int ttm_mem_evict_wait_busy(struct ttm_buffer_object *busy_bo,
 644                                    struct ttm_operation_ctx *ctx,
 645                                    struct ww_acquire_ctx *ticket)
 646 {
 647         int r;
 648
 649         if (!busy_bo || !ticket)
 650                 return -EBUSY;
 651
 652         if (ctx->interruptible)
 653                 r = dma_resv_lock_interruptible(busy_bo->base.resv,
 654                                                           ticket);
 655         else
 656                 r = dma_resv_lock(busy_bo->base.resv, ticket);
 657
 658         /*
 659          * TODO: It would be better to keep the BO locked until allocation is at
 660          * least tried one more time, but that would mean a much larger rework
 661          * of TTM.
 662          */
 663         if (!r)
 664                 dma_resv_unlock(busy_bo->base.resv);
 665
 666         return r == -EDEADLK ? -EBUSY : r;
 667 }
 668
 669 int ttm_mem_evict_first(struct ttm_device *bdev,
 670                         struct ttm_resource_manager *man,
 671                         const struct ttm_place *place,
 672                         struct ttm_operation_ctx *ctx,
 673                         struct ww_acquire_ctx *ticket)
 674 {
 675         struct ttm_buffer_object *bo = NULL, *busy_bo = NULL;
 676         bool locked = false;
 677         unsigned i;
 678         int ret;
 679
 680         spin_lock(&bdev->lru_lock);
 681         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
 682                 list_for_each_entry(bo, &man->lru[i], lru) {
 683                         bool busy;
 684
 685                         if (!ttm_bo_evict_swapout_allowable(bo, ctx, place,
 686                                                             &locked, &busy)) {
 687                                 if (busy && !busy_bo && ticket !=
 688                                     dma_resv_locking_ctx(bo->base.resv))
 689                                         busy_bo = bo;
 690                                 continue;
 691                         }
 692
 693                         if (!ttm_bo_get_unless_zero(bo)) {
 694                                 if (locked)
 695                                         dma_resv_unlock(bo->base.resv);
 696                                 continue;
 697                         }
 698                         break;
 699                 }
 700
 701                 /* If the inner loop terminated early, we have our candidate */
 702                 if (&bo->lru != &man->lru[i])
 703                         break;
 704
 705                 bo = NULL;
 706         }
 707
 708         if (!bo) {
 709                 if (busy_bo && !ttm_bo_get_unless_zero(busy_bo))
 710                         busy_bo = NULL;
 711                 spin_unlock(&bdev->lru_lock);
 712                 ret = ttm_mem_evict_wait_busy(busy_bo, ctx, ticket);
 713                 if (busy_bo)
 714                         ttm_bo_put(busy_bo);
 715                 return ret;
 716         }
 717
 718         if (bo->deleted) {
 719                 ret = ttm_bo_cleanup_refs(bo, ctx->interruptible,
 720                                           ctx->no_wait_gpu, locked);
 721                 ttm_bo_put(bo);
 722                 return ret;
 723         }
 724
 725         spin_unlock(&bdev->lru_lock);
 726
 727         ret = ttm_bo_evict(bo, ctx);
 728         if (locked)
 729                 ttm_bo_unreserve(bo);
 730         else
 731                 ttm_bo_move_to_lru_tail_unlocked(bo);
 732
 733         ttm_bo_put(bo);
 734         return ret;
 735 }
 736
 737 /*
 738  * Add the last move fence to the BO and reserve a new shared slot. We only use
 739  * a shared slot to avoid unecessary sync and rely on the subsequent bo move to
 740  * either stall or use an exclusive fence respectively set bo->moving.
 741  */
 742 static int ttm_bo_add_move_fence(struct ttm_buffer_object *bo,
 743                                  struct ttm_resource_manager *man,
 744                                  struct ttm_resource *mem,
 745                                  bool no_wait_gpu)
 746 {
 747         struct dma_fence *fence;
 748         int ret;
 749
 750         spin_lock(&man->move_lock);
 751         fence = dma_fence_get(man->move);
 752         spin_unlock(&man->move_lock);
 753
 754         if (!fence)
 755                 return 0;
 756
 757         if (no_wait_gpu) {
 758                 ret = dma_fence_is_signaled(fence) ? 0 : -EBUSY;
 759                 dma_fence_put(fence);
 760                 return ret;
 761         }
 762
 763         dma_resv_add_shared_fence(bo->base.resv, fence);
 764
 765         ret = dma_resv_reserve_shared(bo->base.resv, 1);
 766         if (unlikely(ret)) {
 767                 dma_fence_put(fence);
 768                 return ret;
 769         }
 770
 771         dma_fence_put(bo->moving);
 772         bo->moving = fence;
 773         return 0;
 774 }
 775
 776 /*
 777  * Repeatedly evict memory from the LRU for @mem_type until we create enough
 778  * space, or we've evicted everything and there isn't enough space.
 779  */
 780 static int ttm_bo_mem_force_space(struct ttm_buffer_object *bo,
 781                                   const struct ttm_place *place,
 782                                   struct ttm_resource **mem,
 783                                   struct ttm_operation_ctx *ctx)
 784 {
 785         struct ttm_device *bdev = bo->bdev;
 786         struct ttm_resource_manager *man;
 787         struct ww_acquire_ctx *ticket;
 788         int ret;
 789
 790         man = ttm_manager_type(bdev, place->mem_type);
 791         ticket = dma_resv_locking_ctx(bo->base.resv);
 792         do {
 793                 ret = ttm_resource_alloc(bo, place, mem);
 794                 if (likely(!ret))
 795                         break;
 796                 if (unlikely(ret != -ENOSPC))
 797                         return ret;
 798                 ret = ttm_mem_evict_first(bdev, man, place, ctx,
 799                                           ticket);
 800                 if (unlikely(ret != 0))
 801                         return ret;
 802         } while (1);
 803
 804         return ttm_bo_add_move_fence(bo, man, *mem, ctx->no_wait_gpu);
 805 }
 806
 807 /*
 808  * Creates space for memory region @mem according to its type.
 809  *
 810  * This function first searches for free space in compatible memory types in
 811  * the priority order defined by the driver.  If free space isn't found, then
 812  * ttm_bo_mem_force_space is attempted in priority order to evict and find
 813  * space.
 814  */
 815 int ttm_bo_mem_space(struct ttm_buffer_object *bo,
 816                         struct ttm_placement *placement,
 817                         struct ttm_resource **mem,
 818                         struct ttm_operation_ctx *ctx)
 819 {
 820         struct ttm_device *bdev = bo->bdev;
 821         bool type_found = false;
 822         int i, ret;
 823
 824         ret = dma_resv_reserve_shared(bo->base.resv, 1);
 825         if (unlikely(ret))
 826                 return ret;
 827
 828         for (i = 0; i < placement->num_placement; ++i) {
 829                 const struct ttm_place *place = &placement->placement[i];
 830                 struct ttm_resource_manager *man;
 831
 832                 man = ttm_manager_type(bdev, place->mem_type);
 833                 if (!man || !ttm_resource_manager_used(man))
 834                         continue;
 835
 836                 type_found = true;
 837                 ret = ttm_resource_alloc(bo, place, mem);
 838                 if (ret == -ENOSPC)
 839                         continue;
 840                 if (unlikely(ret))
 841                         goto error;
 842
 843                 ret = ttm_bo_add_move_fence(bo, man, *mem, ctx->no_wait_gpu);
 844                 if (unlikely(ret)) {
 845                         ttm_resource_free(bo, mem);
 846                         if (ret == -EBUSY)
 847                                 continue;
 848
 849                         goto error;
 850                 }
 851                 return 0;
 852         }
 853
 854         for (i = 0; i < placement->num_busy_placement; ++i) {
 855                 const struct ttm_place *place = &placement->busy_placement[i];
 856                 struct ttm_resource_manager *man;
 857
 858                 man = ttm_manager_type(bdev, place->mem_type);
 859                 if (!man || !ttm_resource_manager_used(man))
 860                         continue;
 861
 862                 type_found = true;
 863                 ret = ttm_bo_mem_force_space(bo, place, mem, ctx);
 864                 if (likely(!ret))
 865                         return 0;
 866
 867                 if (ret && ret != -EBUSY)
 868                         goto error;
 869         }
 870
 871         ret = -ENOMEM;
 872         if (!type_found) {
 873                 pr_err(TTM_PFX "No compatible memory type found\n");
 874                 ret = -EINVAL;
 875         }
 876
 877 error:
 878         if (bo->resource->mem_type == TTM_PL_SYSTEM && !bo->pin_count)
 879                 ttm_bo_move_to_lru_tail_unlocked(bo);
 880
 881         return ret;
 882 }
 883 EXPORT_SYMBOL(ttm_bo_mem_space);
 884
 885 static int ttm_bo_move_buffer(struct ttm_buffer_object *bo,
 886                               struct ttm_placement *placement,
 887                               struct ttm_operation_ctx *ctx)
 888 {
 889         struct ttm_resource *mem;
 890         struct ttm_place hop;
 891         int ret;
 892
 893         dma_resv_assert_held(bo->base.resv);
 894
 895         /*
 896          * Determine where to move the buffer.
 897          *
 898          * If driver determines move is going to need
 899          * an extra step then it will return -EMULTIHOP
 900          * and the buffer will be moved to the temporary
 901          * stop and the driver will be called to make
 902          * the second hop.
 903          */
 904         ret = ttm_bo_mem_space(bo, placement, &mem, ctx);
 905         if (ret)
 906                 return ret;
 907 bounce:
 908         ret = ttm_bo_handle_move_mem(bo, mem, false, ctx, &hop);
 909         if (ret == -EMULTIHOP) {
 910                 ret = ttm_bo_bounce_temp_buffer(bo, &mem, ctx, &hop);
 911                 if (ret)
 912                         goto out;
 913                 /* try and move to final place now. */
 914                 goto bounce;
 915         }
 916 out:
 917         if (ret)
 918                 ttm_resource_free(bo, &mem);
 919         return ret;
 920 }
 921
 922 int ttm_bo_validate(struct ttm_buffer_object *bo,
 923                     struct ttm_placement *placement,
 924                     struct ttm_operation_ctx *ctx)
 925 {
 926         int ret;
 927
 928         dma_resv_assert_held(bo->base.resv);
 929
 930         /*
 931          * Remove the backing store if no placement is given.
 932          */
 933         if (!placement->num_placement && !placement->num_busy_placement)
 934                 return ttm_bo_pipeline_gutting(bo);
 935
 936         /*
 937          * Check whether we need to move buffer.
 938          */
 939         if (!ttm_resource_compat(bo->resource, placement)) {
 940                 ret = ttm_bo_move_buffer(bo, placement, ctx);
 941                 if (ret)
 942                         return ret;
 943         }
 944         /*
 945          * We might need to add a TTM.
 946          */
 947         if (bo->resource->mem_type == TTM_PL_SYSTEM) {
 948                 ret = ttm_tt_create(bo, true);
 949                 if (ret)
 950                         return ret;
 951         }
 952         return 0;
 953 }
 954 EXPORT_SYMBOL(ttm_bo_validate);
 955
 956 int ttm_bo_init_reserved(struct ttm_device *bdev,
 957                          struct ttm_buffer_object *bo,
 958                          size_t size,
 959                          enum ttm_bo_type type,
 960                          struct ttm_placement *placement,
 961                          uint32_t page_alignment,
 962                          struct ttm_operation_ctx *ctx,
 963                          struct sg_table *sg,
 964                          struct dma_resv *resv,
 965                          void (*destroy) (struct ttm_buffer_object *))
 966 {
 967         static const struct ttm_place sys_mem = { .mem_type = TTM_PL_SYSTEM };
 968         bool locked;
 969         int ret;
 970
 971         bo->destroy = destroy ? destroy : ttm_bo_default_destroy;
 972
 973         kref_init(&bo->kref);
 974         INIT_LIST_HEAD(&bo->lru);
 975         INIT_LIST_HEAD(&bo->ddestroy);
 976         bo->bdev = bdev;
 977         bo->type = type;
 978         bo->page_alignment = page_alignment;
 979         bo->moving = NULL;
 980         bo->pin_count = 0;
 981         bo->sg = sg;
 982         if (resv) {
 983                 bo->base.resv = resv;
 984                 dma_resv_assert_held(bo->base.resv);
 985         } else {
 986                 bo->base.resv = &bo->base._resv;
 987         }
 988         atomic_inc(&ttm_glob.bo_count);
 989
 990         ret = ttm_resource_alloc(bo, &sys_mem, &bo->resource);
 991         if (unlikely(ret)) {
 992                 ttm_bo_put(bo);
 993                 return ret;
 994         }
 995
 996         /*
 997          * For ttm_bo_type_device buffers, allocate
 998          * address space from the device.
 999          */
1000         if (bo->type == ttm_bo_type_device ||
1001             bo->type == ttm_bo_type_sg)
1002                 ret = drm_vma_offset_add(bdev->vma_manager, &bo->base.vma_node,
1003                                          bo->resource->num_pages);
1004
1005         /* passed reservation objects should already be locked,
1006          * since otherwise lockdep will be angered in radeon.
1007          */
1008         if (!resv) {
1009                 locked = dma_resv_trylock(bo->base.resv);
1010                 WARN_ON(!locked);
1011         }
1012
1013         if (likely(!ret))
1014                 ret = ttm_bo_validate(bo, placement, ctx);
1015
1016         if (unlikely(ret)) {
1017                 if (!resv)
1018                         ttm_bo_unreserve(bo);
1019
1020                 ttm_bo_put(bo);
1021                 return ret;
1022         }
1023
1024         ttm_bo_move_to_lru_tail_unlocked(bo);
1025
1026         return ret;
1027 }
1028 EXPORT_SYMBOL(ttm_bo_init_reserved);
1029
1030 int ttm_bo_init(struct ttm_device *bdev,
1031                 struct ttm_buffer_object *bo,
1032                 size_t size,
1033                 enum ttm_bo_type type,
1034                 struct ttm_placement *placement,
1035                 uint32_t page_alignment,
1036                 bool interruptible,
1037                 struct sg_table *sg,
1038                 struct dma_resv *resv,
1039                 void (*destroy) (struct ttm_buffer_object *))
1040 {
1041         struct ttm_operation_ctx ctx = { interruptible, false };
1042         int ret;
1043
1044         ret = ttm_bo_init_reserved(bdev, bo, size, type, placement,
1045                                    page_alignment, &ctx, sg, resv, destroy);
1046         if (ret)
1047                 return ret;
1048
1049         if (!resv)
1050                 ttm_bo_unreserve(bo);
1051
1052         return 0;
1053 }
1054 EXPORT_SYMBOL(ttm_bo_init);
1055
1056 /*
1057  * buffer object vm functions.
1058  */
1059
1060 void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo)
1061 {
1062         struct ttm_device *bdev = bo->bdev;
1063
1064         drm_vma_node_unmap(&bo->base.vma_node, bdev->dev_mapping);
1065         ttm_mem_io_free(bdev, bo->resource);
1066 }
1067 EXPORT_SYMBOL(ttm_bo_unmap_virtual);
1068
1069 int ttm_bo_wait(struct ttm_buffer_object *bo,
1070                 bool interruptible, bool no_wait)
1071 {
1072         long timeout = 15 * HZ;
1073
1074         if (no_wait) {
1075                 if (dma_resv_test_signaled(bo->base.resv, true))
1076                         return 0;
1077                 else
1078                         return -EBUSY;
1079         }
1080
1081         timeout = dma_resv_wait_timeout(bo->base.resv, true, interruptible,
1082                                         timeout);
1083         if (timeout < 0)
1084                 return timeout;
1085
1086         if (timeout == 0)
1087                 return -EBUSY;
1088
1089         return 0;
1090 }
1091 EXPORT_SYMBOL(ttm_bo_wait);
1092
1093 int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx,
1094                    gfp_t gfp_flags)
1095 {
1096         struct ttm_place place;
1097         bool locked;
1098         int ret;
1099
1100         /*
1101          * While the bo may already reside in SYSTEM placement, set
1102          * SYSTEM as new placement to cover also the move further below.
1103          * The driver may use the fact that we're moving from SYSTEM
1104          * as an indication that we're about to swap out.
1105          */
1106         memset(&place, 0, sizeof(place));
1107         place.mem_type = bo->resource->mem_type;
1108         if (!ttm_bo_evict_swapout_allowable(bo, ctx, &place, &locked, NULL))
1109                 return -EBUSY;
1110
1111         if (!bo->ttm || !ttm_tt_is_populated(bo->ttm) ||
1112             bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL ||
1113             bo->ttm->page_flags & TTM_TT_FLAG_SWAPPED ||
1114             !ttm_bo_get_unless_zero(bo)) {
1115                 if (locked)
1116                         dma_resv_unlock(bo->base.resv);
1117                 return -EBUSY;
1118         }
1119
1120         if (bo->deleted) {
1121                 ret = ttm_bo_cleanup_refs(bo, false, false, locked);
1122                 ttm_bo_put(bo);
1123                 return ret == -EBUSY ? -ENOSPC : ret;
1124         }
1125
1126         ttm_bo_move_to_pinned(bo);
1127         /* TODO: Cleanup the locking */
1128         spin_unlock(&bo->bdev->lru_lock);
1129
1130         /*
1131          * Move to system cached
1132          */
1133         if (bo->resource->mem_type != TTM_PL_SYSTEM) {
1134                 struct ttm_operation_ctx ctx = { false, false };
1135                 struct ttm_resource *evict_mem;
1136                 struct ttm_place hop;
1137
1138                 memset(&hop, 0, sizeof(hop));
1139                 place.mem_type = TTM_PL_SYSTEM;
1140                 ret = ttm_resource_alloc(bo, &place, &evict_mem);
1141                 if (unlikely(ret))
1142                         goto out;
1143
1144                 ret = ttm_bo_handle_move_mem(bo, evict_mem, true, &ctx, &hop);
1145                 if (unlikely(ret != 0)) {
1146                         WARN(ret == -EMULTIHOP, "Unexpected multihop in swaput - likely driver bug.\n");
1147                         goto out;
1148                 }
1149         }
1150
1151         /*
1152          * Make sure BO is idle.
1153          */
1154         ret = ttm_bo_wait(bo, false, false);
1155         if (unlikely(ret != 0))
1156                 goto out;
1157
1158         ttm_bo_unmap_virtual(bo);
1159
1160         /*
1161          * Swap out. Buffer will be swapped in again as soon as
1162          * anyone tries to access a ttm page.
1163          */
1164         if (bo->bdev->funcs->swap_notify)
1165                 bo->bdev->funcs->swap_notify(bo);
1166
1167         if (ttm_tt_is_populated(bo->ttm))
1168                 ret = ttm_tt_swapout(bo->bdev, bo->ttm, gfp_flags);
1169 out:
1170
1171         /*
1172          * Unreserve without putting on LRU to avoid swapping out an
1173          * already swapped buffer.
1174          */
1175         if (locked)
1176                 dma_resv_unlock(bo->base.resv);
1177         ttm_bo_put(bo);
1178         return ret == -EBUSY ? -ENOSPC : ret;
1179 }
1180
1181 void ttm_bo_tt_destroy(struct ttm_buffer_object *bo)
1182 {
1183         if (bo->ttm == NULL)
1184                 return;
1185
1186         ttm_tt_unpopulate(bo->bdev, bo->ttm);
1187         ttm_tt_destroy(bo->bdev, bo->ttm);
1188         bo->ttm = NULL;
1189 }