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 void ttm_bo_del_from_lru(struct ttm_buffer_object *bo)
  73 {
  74         struct ttm_device *bdev = bo->bdev;
  75
  76         list_del_init(&bo->lru);
  77
  78         if (bdev->funcs->del_from_lru_notify)
  79                 bdev->funcs->del_from_lru_notify(bo);
  80 }
  81
  82 static void ttm_bo_bulk_move_set_pos(struct ttm_lru_bulk_move_pos *pos,
  83                                      struct ttm_buffer_object *bo)
  84 {
  85         if (!pos->first)
  86                 pos->first = bo;
  87         pos->last = bo;
  88 }
  89
  90 void ttm_bo_move_to_lru_tail(struct ttm_buffer_object *bo,
  91                              struct ttm_resource *mem,
  92                              struct ttm_lru_bulk_move *bulk)
  93 {
  94         struct ttm_device *bdev = bo->bdev;
  95         struct ttm_resource_manager *man;
  96
  97         if (!bo->deleted)
  98                 dma_resv_assert_held(bo->base.resv);
  99
 100         if (bo->pin_count) {
 101                 ttm_bo_del_from_lru(bo);
 102                 return;
 103         }
 104
 105         if (!mem)
 106                 return;
 107
 108         man = ttm_manager_type(bdev, mem->mem_type);
 109         list_move_tail(&bo->lru, &man->lru[bo->priority]);
 110
 111         if (bdev->funcs->del_from_lru_notify)
 112                 bdev->funcs->del_from_lru_notify(bo);
 113
 114         if (bulk && !bo->pin_count) {
 115                 switch (bo->resource->mem_type) {
 116                 case TTM_PL_TT:
 117                         ttm_bo_bulk_move_set_pos(&bulk->tt[bo->priority], bo);
 118                         break;
 119
 120                 case TTM_PL_VRAM:
 121                         ttm_bo_bulk_move_set_pos(&bulk->vram[bo->priority], bo);
 122                         break;
 123                 }
 124         }
 125 }
 126 EXPORT_SYMBOL(ttm_bo_move_to_lru_tail);
 127
 128 void ttm_bo_bulk_move_lru_tail(struct ttm_lru_bulk_move *bulk)
 129 {
 130         unsigned i;
 131
 132         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
 133                 struct ttm_lru_bulk_move_pos *pos = &bulk->tt[i];
 134                 struct ttm_resource_manager *man;
 135
 136                 if (!pos->first)
 137                         continue;
 138
 139                 dma_resv_assert_held(pos->first->base.resv);
 140                 dma_resv_assert_held(pos->last->base.resv);
 141
 142                 man = ttm_manager_type(pos->first->bdev, TTM_PL_TT);
 143                 list_bulk_move_tail(&man->lru[i], &pos->first->lru,
 144                                     &pos->last->lru);
 145         }
 146
 147         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
 148                 struct ttm_lru_bulk_move_pos *pos = &bulk->vram[i];
 149                 struct ttm_resource_manager *man;
 150
 151                 if (!pos->first)
 152                         continue;
 153
 154                 dma_resv_assert_held(pos->first->base.resv);
 155                 dma_resv_assert_held(pos->last->base.resv);
 156
 157                 man = ttm_manager_type(pos->first->bdev, TTM_PL_VRAM);
 158                 list_bulk_move_tail(&man->lru[i], &pos->first->lru,
 159                                     &pos->last->lru);
 160         }
 161 }
 162 EXPORT_SYMBOL(ttm_bo_bulk_move_lru_tail);
 163
 164 static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo,
 165                                   struct ttm_resource *mem, bool evict,
 166                                   struct ttm_operation_ctx *ctx,
 167                                   struct ttm_place *hop)
 168 {
 169         struct ttm_resource_manager *old_man, *new_man;
 170         struct ttm_device *bdev = bo->bdev;
 171         int ret;
 172
 173         old_man = ttm_manager_type(bdev, bo->resource->mem_type);
 174         new_man = ttm_manager_type(bdev, mem->mem_type);
 175
 176         ttm_bo_unmap_virtual(bo);
 177
 178         /*
 179          * Create and bind a ttm if required.
 180          */
 181
 182         if (new_man->use_tt) {
 183                 /* Zero init the new TTM structure if the old location should
 184                  * have used one as well.
 185                  */
 186                 ret = ttm_tt_create(bo, old_man->use_tt);
 187                 if (ret)
 188                         goto out_err;
 189
 190                 if (mem->mem_type != TTM_PL_SYSTEM) {
 191                         ret = ttm_tt_populate(bo->bdev, bo->ttm, ctx);
 192                         if (ret)
 193                                 goto out_err;
 194                 }
 195         }
 196
 197         ret = bdev->funcs->move(bo, evict, ctx, mem, hop);
 198         if (ret) {
 199                 if (ret == -EMULTIHOP)
 200                         return ret;
 201                 goto out_err;
 202         }
 203
 204         ctx->bytes_moved += bo->base.size;
 205         return 0;
 206
 207 out_err:
 208         new_man = ttm_manager_type(bdev, bo->resource->mem_type);
 209         if (!new_man->use_tt)
 210                 ttm_bo_tt_destroy(bo);
 211
 212         return ret;
 213 }
 214
 215 /*
 216  * Call bo::reserved.
 217  * Will release GPU memory type usage on destruction.
 218  * This is the place to put in driver specific hooks to release
 219  * driver private resources.
 220  * Will release the bo::reserved lock.
 221  */
 222
 223 static void ttm_bo_cleanup_memtype_use(struct ttm_buffer_object *bo)
 224 {
 225         if (bo->bdev->funcs->delete_mem_notify)
 226                 bo->bdev->funcs->delete_mem_notify(bo);
 227
 228         ttm_bo_tt_destroy(bo);
 229         ttm_resource_free(bo, &bo->resource);
 230 }
 231
 232 static int ttm_bo_individualize_resv(struct ttm_buffer_object *bo)
 233 {
 234         int r;
 235
 236         if (bo->base.resv == &bo->base._resv)
 237                 return 0;
 238
 239         BUG_ON(!dma_resv_trylock(&bo->base._resv));
 240
 241         r = dma_resv_copy_fences(&bo->base._resv, bo->base.resv);
 242         dma_resv_unlock(&bo->base._resv);
 243         if (r)
 244                 return r;
 245
 246         if (bo->type != ttm_bo_type_sg) {
 247                 /* This works because the BO is about to be destroyed and nobody
 248                  * reference it any more. The only tricky case is the trylock on
 249                  * the resv object while holding the lru_lock.
 250                  */
 251                 spin_lock(&bo->bdev->lru_lock);
 252                 bo->base.resv = &bo->base._resv;
 253                 spin_unlock(&bo->bdev->lru_lock);
 254         }
 255
 256         return r;
 257 }
 258
 259 static void ttm_bo_flush_all_fences(struct ttm_buffer_object *bo)
 260 {
 261         struct dma_resv *resv = &bo->base._resv;
 262         struct dma_resv_list *fobj;
 263         struct dma_fence *fence;
 264         int i;
 265
 266         rcu_read_lock();
 267         fobj = dma_resv_shared_list(resv);
 268         fence = dma_resv_excl_fence(resv);
 269         if (fence && !fence->ops->signaled)
 270                 dma_fence_enable_sw_signaling(fence);
 271
 272         for (i = 0; fobj && i < fobj->shared_count; ++i) {
 273                 fence = rcu_dereference(fobj->shared[i]);
 274
 275                 if (!fence->ops->signaled)
 276                         dma_fence_enable_sw_signaling(fence);
 277         }
 278         rcu_read_unlock();
 279 }
 280
 281 /**
 282  * ttm_bo_cleanup_refs
 283  * If bo idle, remove from lru lists, and unref.
 284  * If not idle, block if possible.
 285  *
 286  * Must be called with lru_lock and reservation held, this function
 287  * will drop the lru lock and optionally the reservation lock before returning.
 288  *
 289  * @bo:                    The buffer object to clean-up
 290  * @interruptible:         Any sleeps should occur interruptibly.
 291  * @no_wait_gpu:           Never wait for gpu. Return -EBUSY instead.
 292  * @unlock_resv:           Unlock the reservation lock as well.
 293  */
 294
 295 static int ttm_bo_cleanup_refs(struct ttm_buffer_object *bo,
 296                                bool interruptible, bool no_wait_gpu,
 297                                bool unlock_resv)
 298 {
 299         struct dma_resv *resv = &bo->base._resv;
 300         int ret;
 301
 302         if (dma_resv_test_signaled(resv, true))
 303                 ret = 0;
 304         else
 305                 ret = -EBUSY;
 306
 307         if (ret && !no_wait_gpu) {
 308                 long lret;
 309
 310                 if (unlock_resv)
 311                         dma_resv_unlock(bo->base.resv);
 312                 spin_unlock(&bo->bdev->lru_lock);
 313
 314                 lret = dma_resv_wait_timeout(resv, true, interruptible,
 315                                              30 * HZ);
 316
 317                 if (lret < 0)
 318                         return lret;
 319                 else if (lret == 0)
 320                         return -EBUSY;
 321
 322                 spin_lock(&bo->bdev->lru_lock);
 323                 if (unlock_resv && !dma_resv_trylock(bo->base.resv)) {
 324                         /*
 325                          * We raced, and lost, someone else holds the reservation now,
 326                          * and is probably busy in ttm_bo_cleanup_memtype_use.
 327                          *
 328                          * Even if it's not the case, because we finished waiting any
 329                          * delayed destruction would succeed, so just return success
 330                          * here.
 331                          */
 332                         spin_unlock(&bo->bdev->lru_lock);
 333                         return 0;
 334                 }
 335                 ret = 0;
 336         }
 337
 338         if (ret || unlikely(list_empty(&bo->ddestroy))) {
 339                 if (unlock_resv)
 340                         dma_resv_unlock(bo->base.resv);
 341                 spin_unlock(&bo->bdev->lru_lock);
 342                 return ret;
 343         }
 344
 345         ttm_bo_del_from_lru(bo);
 346         list_del_init(&bo->ddestroy);
 347         spin_unlock(&bo->bdev->lru_lock);
 348         ttm_bo_cleanup_memtype_use(bo);
 349
 350         if (unlock_resv)
 351                 dma_resv_unlock(bo->base.resv);
 352
 353         ttm_bo_put(bo);
 354
 355         return 0;
 356 }
 357
 358 /*
 359  * Traverse the delayed list, and call ttm_bo_cleanup_refs on all
 360  * encountered buffers.
 361  */
 362 bool ttm_bo_delayed_delete(struct ttm_device *bdev, bool remove_all)
 363 {
 364         struct list_head removed;
 365         bool empty;
 366
 367         INIT_LIST_HEAD(&removed);
 368
 369         spin_lock(&bdev->lru_lock);
 370         while (!list_empty(&bdev->ddestroy)) {
 371                 struct ttm_buffer_object *bo;
 372
 373                 bo = list_first_entry(&bdev->ddestroy, struct ttm_buffer_object,
 374                                       ddestroy);
 375                 list_move_tail(&bo->ddestroy, &removed);
 376                 if (!ttm_bo_get_unless_zero(bo))
 377                         continue;
 378
 379                 if (remove_all || bo->base.resv != &bo->base._resv) {
 380                         spin_unlock(&bdev->lru_lock);
 381                         dma_resv_lock(bo->base.resv, NULL);
 382
 383                         spin_lock(&bdev->lru_lock);
 384                         ttm_bo_cleanup_refs(bo, false, !remove_all, true);
 385
 386                 } else if (dma_resv_trylock(bo->base.resv)) {
 387                         ttm_bo_cleanup_refs(bo, false, !remove_all, true);
 388                 } else {
 389                         spin_unlock(&bdev->lru_lock);
 390                 }
 391
 392                 ttm_bo_put(bo);
 393                 spin_lock(&bdev->lru_lock);
 394         }
 395         list_splice_tail(&removed, &bdev->ddestroy);
 396         empty = list_empty(&bdev->ddestroy);
 397         spin_unlock(&bdev->lru_lock);
 398
 399         return empty;
 400 }
 401
 402 static void ttm_bo_release(struct kref *kref)
 403 {
 404         struct ttm_buffer_object *bo =
 405             container_of(kref, struct ttm_buffer_object, kref);
 406         struct ttm_device *bdev = bo->bdev;
 407         int ret;
 408
 409         WARN_ON_ONCE(bo->pin_count);
 410
 411         if (!bo->deleted) {
 412                 ret = ttm_bo_individualize_resv(bo);
 413                 if (ret) {
 414                         /* Last resort, if we fail to allocate memory for the
 415                          * fences block for the BO to become idle
 416                          */
 417                         dma_resv_wait_timeout(bo->base.resv, true, false,
 418                                               30 * HZ);
 419                 }
 420
 421                 if (bo->bdev->funcs->release_notify)
 422                         bo->bdev->funcs->release_notify(bo);
 423
 424                 drm_vma_offset_remove(bdev->vma_manager, &bo->base.vma_node);
 425                 ttm_mem_io_free(bdev, bo->resource);
 426         }
 427
 428         if (!dma_resv_test_signaled(bo->base.resv, true) ||
 429             !dma_resv_trylock(bo->base.resv)) {
 430                 /* The BO is not idle, resurrect it for delayed destroy */
 431                 ttm_bo_flush_all_fences(bo);
 432                 bo->deleted = true;
 433
 434                 spin_lock(&bo->bdev->lru_lock);
 435
 436                 /*
 437                  * Make pinned bos immediately available to
 438                  * shrinkers, now that they are queued for
 439                  * destruction.
 440                  *
 441                  * FIXME: QXL is triggering this. Can be removed when the
 442                  * driver is fixed.
 443                  */
 444                 if (bo->pin_count) {
 445                         bo->pin_count = 0;
 446                         ttm_bo_move_to_lru_tail(bo, bo->resource, NULL);
 447                 }
 448
 449                 kref_init(&bo->kref);
 450                 list_add_tail(&bo->ddestroy, &bdev->ddestroy);
 451                 spin_unlock(&bo->bdev->lru_lock);
 452
 453                 schedule_delayed_work(&bdev->wq,
 454                                       ((HZ / 100) < 1) ? 1 : HZ / 100);
 455                 return;
 456         }
 457
 458         spin_lock(&bo->bdev->lru_lock);
 459         ttm_bo_del_from_lru(bo);
 460         list_del(&bo->ddestroy);
 461         spin_unlock(&bo->bdev->lru_lock);
 462
 463         ttm_bo_cleanup_memtype_use(bo);
 464         dma_resv_unlock(bo->base.resv);
 465
 466         atomic_dec(&ttm_glob.bo_count);
 467         dma_fence_put(bo->moving);
 468         bo->destroy(bo);
 469 }
 470
 471 void ttm_bo_put(struct ttm_buffer_object *bo)
 472 {
 473         kref_put(&bo->kref, ttm_bo_release);
 474 }
 475 EXPORT_SYMBOL(ttm_bo_put);
 476
 477 int ttm_bo_lock_delayed_workqueue(struct ttm_device *bdev)
 478 {
 479         return cancel_delayed_work_sync(&bdev->wq);
 480 }
 481 EXPORT_SYMBOL(ttm_bo_lock_delayed_workqueue);
 482
 483 void ttm_bo_unlock_delayed_workqueue(struct ttm_device *bdev, int resched)
 484 {
 485         if (resched)
 486                 schedule_delayed_work(&bdev->wq,
 487                                       ((HZ / 100) < 1) ? 1 : HZ / 100);
 488 }
 489 EXPORT_SYMBOL(ttm_bo_unlock_delayed_workqueue);
 490
 491 static int ttm_bo_evict(struct ttm_buffer_object *bo,
 492                         struct ttm_operation_ctx *ctx)
 493 {
 494         struct ttm_device *bdev = bo->bdev;
 495         struct ttm_resource *evict_mem;
 496         struct ttm_placement placement;
 497         struct ttm_place hop;
 498         int ret = 0;
 499
 500         memset(&hop, 0, sizeof(hop));
 501
 502         dma_resv_assert_held(bo->base.resv);
 503
 504         placement.num_placement = 0;
 505         placement.num_busy_placement = 0;
 506         bdev->funcs->evict_flags(bo, &placement);
 507
 508         if (!placement.num_placement && !placement.num_busy_placement) {
 509                 ret = ttm_bo_wait(bo, true, false);
 510                 if (ret)
 511                         return ret;
 512
 513                 /*
 514                  * Since we've already synced, this frees backing store
 515                  * immediately.
 516                  */
 517                 return ttm_bo_pipeline_gutting(bo);
 518         }
 519
 520         ret = ttm_bo_mem_space(bo, &placement, &evict_mem, ctx);
 521         if (ret) {
 522                 if (ret != -ERESTARTSYS) {
 523                         pr_err("Failed to find memory space for buffer 0x%p eviction\n",
 524                                bo);
 525                         ttm_bo_mem_space_debug(bo, &placement);
 526                 }
 527                 goto out;
 528         }
 529
 530         ret = ttm_bo_handle_move_mem(bo, evict_mem, true, ctx, &hop);
 531         if (unlikely(ret)) {
 532                 WARN(ret == -EMULTIHOP, "Unexpected multihop in eviction - likely driver bug\n");
 533                 if (ret != -ERESTARTSYS)
 534                         pr_err("Buffer eviction failed\n");
 535                 ttm_resource_free(bo, &evict_mem);
 536         }
 537 out:
 538         return ret;
 539 }
 540
 541 bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo,
 542                               const struct ttm_place *place)
 543 {
 544         dma_resv_assert_held(bo->base.resv);
 545         if (bo->resource->mem_type == TTM_PL_SYSTEM)
 546                 return true;
 547
 548         /* Don't evict this BO if it's outside of the
 549          * requested placement range
 550          */
 551         if (place->fpfn >= (bo->resource->start + bo->resource->num_pages) ||
 552             (place->lpfn && place->lpfn <= bo->resource->start))
 553                 return false;
 554
 555         return true;
 556 }
 557 EXPORT_SYMBOL(ttm_bo_eviction_valuable);
 558
 559 /*
 560  * Check the target bo is allowable to be evicted or swapout, including cases:
 561  *
 562  * a. if share same reservation object with ctx->resv, have assumption
 563  * reservation objects should already be locked, so not lock again and
 564  * return true directly when either the opreation allow_reserved_eviction
 565  * or the target bo already is in delayed free list;
 566  *
 567  * b. Otherwise, trylock it.
 568  */
 569 static bool ttm_bo_evict_swapout_allowable(struct ttm_buffer_object *bo,
 570                                            struct ttm_operation_ctx *ctx,
 571                                            const struct ttm_place *place,
 572                                            bool *locked, bool *busy)
 573 {
 574         bool ret = false;
 575
 576         if (bo->base.resv == ctx->resv) {
 577                 dma_resv_assert_held(bo->base.resv);
 578                 if (ctx->allow_res_evict)
 579                         ret = true;
 580                 *locked = false;
 581                 if (busy)
 582                         *busy = false;
 583         } else {
 584                 ret = dma_resv_trylock(bo->base.resv);
 585                 *locked = ret;
 586                 if (busy)
 587                         *busy = !ret;
 588         }
 589
 590         if (ret && place && !bo->bdev->funcs->eviction_valuable(bo, place)) {
 591                 ret = false;
 592                 if (*locked) {
 593                         dma_resv_unlock(bo->base.resv);
 594                         *locked = false;
 595                 }
 596         }
 597
 598         return ret;
 599 }
 600
 601 /**
 602  * ttm_mem_evict_wait_busy - wait for a busy BO to become available
 603  *
 604  * @busy_bo: BO which couldn't be locked with trylock
 605  * @ctx: operation context
 606  * @ticket: acquire ticket
 607  *
 608  * Try to lock a busy buffer object to avoid failing eviction.
 609  */
 610 static int ttm_mem_evict_wait_busy(struct ttm_buffer_object *busy_bo,
 611                                    struct ttm_operation_ctx *ctx,
 612                                    struct ww_acquire_ctx *ticket)
 613 {
 614         int r;
 615
 616         if (!busy_bo || !ticket)
 617                 return -EBUSY;
 618
 619         if (ctx->interruptible)
 620                 r = dma_resv_lock_interruptible(busy_bo->base.resv,
 621                                                           ticket);
 622         else
 623                 r = dma_resv_lock(busy_bo->base.resv, ticket);
 624
 625         /*
 626          * TODO: It would be better to keep the BO locked until allocation is at
 627          * least tried one more time, but that would mean a much larger rework
 628          * of TTM.
 629          */
 630         if (!r)
 631                 dma_resv_unlock(busy_bo->base.resv);
 632
 633         return r == -EDEADLK ? -EBUSY : r;
 634 }
 635
 636 int ttm_mem_evict_first(struct ttm_device *bdev,
 637                         struct ttm_resource_manager *man,
 638                         const struct ttm_place *place,
 639                         struct ttm_operation_ctx *ctx,
 640                         struct ww_acquire_ctx *ticket)
 641 {
 642         struct ttm_buffer_object *bo = NULL, *busy_bo = NULL;
 643         bool locked = false;
 644         unsigned i;
 645         int ret;
 646
 647         spin_lock(&bdev->lru_lock);
 648         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) {
 649                 list_for_each_entry(bo, &man->lru[i], lru) {
 650                         bool busy;
 651
 652                         if (!ttm_bo_evict_swapout_allowable(bo, ctx, place,
 653                                                             &locked, &busy)) {
 654                                 if (busy && !busy_bo && ticket !=
 655                                     dma_resv_locking_ctx(bo->base.resv))
 656                                         busy_bo = bo;
 657                                 continue;
 658                         }
 659
 660                         if (!ttm_bo_get_unless_zero(bo)) {
 661                                 if (locked)
 662                                         dma_resv_unlock(bo->base.resv);
 663                                 continue;
 664                         }
 665                         break;
 666                 }
 667
 668                 /* If the inner loop terminated early, we have our candidate */
 669                 if (&bo->lru != &man->lru[i])
 670                         break;
 671
 672                 bo = NULL;
 673         }
 674
 675         if (!bo) {
 676                 if (busy_bo && !ttm_bo_get_unless_zero(busy_bo))
 677                         busy_bo = NULL;
 678                 spin_unlock(&bdev->lru_lock);
 679                 ret = ttm_mem_evict_wait_busy(busy_bo, ctx, ticket);
 680                 if (busy_bo)
 681                         ttm_bo_put(busy_bo);
 682                 return ret;
 683         }
 684
 685         if (bo->deleted) {
 686                 ret = ttm_bo_cleanup_refs(bo, ctx->interruptible,
 687                                           ctx->no_wait_gpu, locked);
 688                 ttm_bo_put(bo);
 689                 return ret;
 690         }
 691
 692         spin_unlock(&bdev->lru_lock);
 693
 694         ret = ttm_bo_evict(bo, ctx);
 695         if (locked)
 696                 ttm_bo_unreserve(bo);
 697
 698         ttm_bo_put(bo);
 699         return ret;
 700 }
 701
 702 /*
 703  * Add the last move fence to the BO and reserve a new shared slot. We only use
 704  * a shared slot to avoid unecessary sync and rely on the subsequent bo move to
 705  * either stall or use an exclusive fence respectively set bo->moving.
 706  */
 707 static int ttm_bo_add_move_fence(struct ttm_buffer_object *bo,
 708                                  struct ttm_resource_manager *man,
 709                                  struct ttm_resource *mem,
 710                                  bool no_wait_gpu)
 711 {
 712         struct dma_fence *fence;
 713         int ret;
 714
 715         spin_lock(&man->move_lock);
 716         fence = dma_fence_get(man->move);
 717         spin_unlock(&man->move_lock);
 718
 719         if (!fence)
 720                 return 0;
 721
 722         if (no_wait_gpu) {
 723                 ret = dma_fence_is_signaled(fence) ? 0 : -EBUSY;
 724                 dma_fence_put(fence);
 725                 return ret;
 726         }
 727
 728         dma_resv_add_shared_fence(bo->base.resv, fence);
 729
 730         ret = dma_resv_reserve_shared(bo->base.resv, 1);
 731         if (unlikely(ret)) {
 732                 dma_fence_put(fence);
 733                 return ret;
 734         }
 735
 736         dma_fence_put(bo->moving);
 737         bo->moving = fence;
 738         return 0;
 739 }
 740
 741 /*
 742  * Repeatedly evict memory from the LRU for @mem_type until we create enough
 743  * space, or we've evicted everything and there isn't enough space.
 744  */
 745 static int ttm_bo_mem_force_space(struct ttm_buffer_object *bo,
 746                                   const struct ttm_place *place,
 747                                   struct ttm_resource **mem,
 748                                   struct ttm_operation_ctx *ctx)
 749 {
 750         struct ttm_device *bdev = bo->bdev;
 751         struct ttm_resource_manager *man;
 752         struct ww_acquire_ctx *ticket;
 753         int ret;
 754
 755         man = ttm_manager_type(bdev, place->mem_type);
 756         ticket = dma_resv_locking_ctx(bo->base.resv);
 757         do {
 758                 ret = ttm_resource_alloc(bo, place, mem);
 759                 if (likely(!ret))
 760                         break;
 761                 if (unlikely(ret != -ENOSPC))
 762                         return ret;
 763                 ret = ttm_mem_evict_first(bdev, man, place, ctx,
 764                                           ticket);
 765                 if (unlikely(ret != 0))
 766                         return ret;
 767         } while (1);
 768
 769         return ttm_bo_add_move_fence(bo, man, *mem, ctx->no_wait_gpu);
 770 }
 771
 772 /*
 773  * Creates space for memory region @mem according to its type.
 774  *
 775  * This function first searches for free space in compatible memory types in
 776  * the priority order defined by the driver.  If free space isn't found, then
 777  * ttm_bo_mem_force_space is attempted in priority order to evict and find
 778  * space.
 779  */
 780 int ttm_bo_mem_space(struct ttm_buffer_object *bo,
 781                         struct ttm_placement *placement,
 782                         struct ttm_resource **mem,
 783                         struct ttm_operation_ctx *ctx)
 784 {
 785         struct ttm_device *bdev = bo->bdev;
 786         bool type_found = false;
 787         int i, ret;
 788
 789         ret = dma_resv_reserve_shared(bo->base.resv, 1);
 790         if (unlikely(ret))
 791                 return ret;
 792
 793         for (i = 0; i < placement->num_placement; ++i) {
 794                 const struct ttm_place *place = &placement->placement[i];
 795                 struct ttm_resource_manager *man;
 796
 797                 man = ttm_manager_type(bdev, place->mem_type);
 798                 if (!man || !ttm_resource_manager_used(man))
 799                         continue;
 800
 801                 type_found = true;
 802                 ret = ttm_resource_alloc(bo, place, mem);
 803                 if (ret == -ENOSPC)
 804                         continue;
 805                 if (unlikely(ret))
 806                         goto error;
 807
 808                 ret = ttm_bo_add_move_fence(bo, man, *mem, ctx->no_wait_gpu);
 809                 if (unlikely(ret)) {
 810                         ttm_resource_free(bo, mem);
 811                         if (ret == -EBUSY)
 812                                 continue;
 813
 814                         goto error;
 815                 }
 816                 return 0;
 817         }
 818
 819         for (i = 0; i < placement->num_busy_placement; ++i) {
 820                 const struct ttm_place *place = &placement->busy_placement[i];
 821                 struct ttm_resource_manager *man;
 822
 823                 man = ttm_manager_type(bdev, place->mem_type);
 824                 if (!man || !ttm_resource_manager_used(man))
 825                         continue;
 826
 827                 type_found = true;
 828                 ret = ttm_bo_mem_force_space(bo, place, mem, ctx);
 829                 if (likely(!ret))
 830                         return 0;
 831
 832                 if (ret && ret != -EBUSY)
 833                         goto error;
 834         }
 835
 836         ret = -ENOMEM;
 837         if (!type_found) {
 838                 pr_err(TTM_PFX "No compatible memory type found\n");
 839                 ret = -EINVAL;
 840         }
 841
 842 error:
 843         if (bo->resource->mem_type == TTM_PL_SYSTEM && !bo->pin_count)
 844                 ttm_bo_move_to_lru_tail_unlocked(bo);
 845
 846         return ret;
 847 }
 848 EXPORT_SYMBOL(ttm_bo_mem_space);
 849
 850 static int ttm_bo_bounce_temp_buffer(struct ttm_buffer_object *bo,
 851                                      struct ttm_resource **mem,
 852                                      struct ttm_operation_ctx *ctx,
 853                                      struct ttm_place *hop)
 854 {
 855         struct ttm_placement hop_placement;
 856         struct ttm_resource *hop_mem;
 857         int ret;
 858
 859         hop_placement.num_placement = hop_placement.num_busy_placement = 1;
 860         hop_placement.placement = hop_placement.busy_placement = hop;
 861
 862         /* find space in the bounce domain */
 863         ret = ttm_bo_mem_space(bo, &hop_placement, &hop_mem, ctx);
 864         if (ret)
 865                 return ret;
 866         /* move to the bounce domain */
 867         ret = ttm_bo_handle_move_mem(bo, hop_mem, false, ctx, NULL);
 868         if (ret) {
 869                 ttm_resource_free(bo, &hop_mem);
 870                 return ret;
 871         }
 872         return 0;
 873 }
 874
 875 static int ttm_bo_move_buffer(struct ttm_buffer_object *bo,
 876                               struct ttm_placement *placement,
 877                               struct ttm_operation_ctx *ctx)
 878 {
 879         struct ttm_resource *mem;
 880         struct ttm_place hop;
 881         int ret;
 882
 883         dma_resv_assert_held(bo->base.resv);
 884
 885         /*
 886          * Determine where to move the buffer.
 887          *
 888          * If driver determines move is going to need
 889          * an extra step then it will return -EMULTIHOP
 890          * and the buffer will be moved to the temporary
 891          * stop and the driver will be called to make
 892          * the second hop.
 893          */
 894         ret = ttm_bo_mem_space(bo, placement, &mem, ctx);
 895         if (ret)
 896                 return ret;
 897 bounce:
 898         ret = ttm_bo_handle_move_mem(bo, mem, false, ctx, &hop);
 899         if (ret == -EMULTIHOP) {
 900                 ret = ttm_bo_bounce_temp_buffer(bo, &mem, ctx, &hop);
 901                 if (ret)
 902                         goto out;
 903                 /* try and move to final place now. */
 904                 goto bounce;
 905         }
 906 out:
 907         if (ret)
 908                 ttm_resource_free(bo, &mem);
 909         return ret;
 910 }
 911
 912 static bool ttm_bo_places_compat(const struct ttm_place *places,
 913                                  unsigned num_placement,
 914                                  struct ttm_resource *mem,
 915                                  uint32_t *new_flags)
 916 {
 917         unsigned i;
 918
 919         for (i = 0; i < num_placement; i++) {
 920                 const struct ttm_place *heap = &places[i];
 921
 922                 if ((mem->start < heap->fpfn ||
 923                      (heap->lpfn != 0 && (mem->start + mem->num_pages) > heap->lpfn)))
 924                         continue;
 925
 926                 *new_flags = heap->flags;
 927                 if ((mem->mem_type == heap->mem_type) &&
 928                     (!(*new_flags & TTM_PL_FLAG_CONTIGUOUS) ||
 929                      (mem->placement & TTM_PL_FLAG_CONTIGUOUS)))
 930                         return true;
 931         }
 932         return false;
 933 }
 934
 935 bool ttm_bo_mem_compat(struct ttm_placement *placement,
 936                        struct ttm_resource *mem,
 937                        uint32_t *new_flags)
 938 {
 939         if (ttm_bo_places_compat(placement->placement, placement->num_placement,
 940                                  mem, new_flags))
 941                 return true;
 942
 943         if ((placement->busy_placement != placement->placement ||
 944              placement->num_busy_placement > placement->num_placement) &&
 945             ttm_bo_places_compat(placement->busy_placement,
 946                                  placement->num_busy_placement,
 947                                  mem, new_flags))
 948                 return true;
 949
 950         return false;
 951 }
 952 EXPORT_SYMBOL(ttm_bo_mem_compat);
 953
 954 int ttm_bo_validate(struct ttm_buffer_object *bo,
 955                     struct ttm_placement *placement,
 956                     struct ttm_operation_ctx *ctx)
 957 {
 958         int ret;
 959         uint32_t new_flags;
 960
 961         dma_resv_assert_held(bo->base.resv);
 962
 963         /*
 964          * Remove the backing store if no placement is given.
 965          */
 966         if (!placement->num_placement && !placement->num_busy_placement)
 967                 return ttm_bo_pipeline_gutting(bo);
 968
 969         /*
 970          * Check whether we need to move buffer.
 971          */
 972         if (!ttm_bo_mem_compat(placement, bo->resource, &new_flags)) {
 973                 ret = ttm_bo_move_buffer(bo, placement, ctx);
 974                 if (ret)
 975                         return ret;
 976         }
 977         /*
 978          * We might need to add a TTM.
 979          */
 980         if (bo->resource->mem_type == TTM_PL_SYSTEM) {
 981                 ret = ttm_tt_create(bo, true);
 982                 if (ret)
 983                         return ret;
 984         }
 985         return 0;
 986 }
 987 EXPORT_SYMBOL(ttm_bo_validate);
 988
 989 int ttm_bo_init_reserved(struct ttm_device *bdev,
 990                          struct ttm_buffer_object *bo,
 991                          size_t size,
 992                          enum ttm_bo_type type,
 993                          struct ttm_placement *placement,
 994                          uint32_t page_alignment,
 995                          struct ttm_operation_ctx *ctx,
 996                          struct sg_table *sg,
 997                          struct dma_resv *resv,
 998                          void (*destroy) (struct ttm_buffer_object *))
 999 {
1000         static const struct ttm_place sys_mem = { .mem_type = TTM_PL_SYSTEM };
1001         bool locked;
1002         int ret;
1003
1004         bo->destroy = destroy ? destroy : ttm_bo_default_destroy;
1005
1006         kref_init(&bo->kref);
1007         INIT_LIST_HEAD(&bo->lru);
1008         INIT_LIST_HEAD(&bo->ddestroy);
1009         bo->bdev = bdev;
1010         bo->type = type;
1011         bo->page_alignment = page_alignment;
1012         bo->moving = NULL;
1013         bo->pin_count = 0;
1014         bo->sg = sg;
1015         if (resv) {
1016                 bo->base.resv = resv;
1017                 dma_resv_assert_held(bo->base.resv);
1018         } else {
1019                 bo->base.resv = &bo->base._resv;
1020         }
1021         atomic_inc(&ttm_glob.bo_count);
1022
1023         ret = ttm_resource_alloc(bo, &sys_mem, &bo->resource);
1024         if (unlikely(ret)) {
1025                 ttm_bo_put(bo);
1026                 return ret;
1027         }
1028
1029         /*
1030          * For ttm_bo_type_device buffers, allocate
1031          * address space from the device.
1032          */
1033         if (bo->type == ttm_bo_type_device ||
1034             bo->type == ttm_bo_type_sg)
1035                 ret = drm_vma_offset_add(bdev->vma_manager, &bo->base.vma_node,
1036                                          bo->resource->num_pages);
1037
1038         /* passed reservation objects should already be locked,
1039          * since otherwise lockdep will be angered in radeon.
1040          */
1041         if (!resv) {
1042                 locked = dma_resv_trylock(bo->base.resv);
1043                 WARN_ON(!locked);
1044         }
1045
1046         if (likely(!ret))
1047                 ret = ttm_bo_validate(bo, placement, ctx);
1048
1049         if (unlikely(ret)) {
1050                 if (!resv)
1051                         ttm_bo_unreserve(bo);
1052
1053                 ttm_bo_put(bo);
1054                 return ret;
1055         }
1056
1057         ttm_bo_move_to_lru_tail_unlocked(bo);
1058
1059         return ret;
1060 }
1061 EXPORT_SYMBOL(ttm_bo_init_reserved);
1062
1063 int ttm_bo_init(struct ttm_device *bdev,
1064                 struct ttm_buffer_object *bo,
1065                 size_t size,
1066                 enum ttm_bo_type type,
1067                 struct ttm_placement *placement,
1068                 uint32_t page_alignment,
1069                 bool interruptible,
1070                 struct sg_table *sg,
1071                 struct dma_resv *resv,
1072                 void (*destroy) (struct ttm_buffer_object *))
1073 {
1074         struct ttm_operation_ctx ctx = { interruptible, false };
1075         int ret;
1076
1077         ret = ttm_bo_init_reserved(bdev, bo, size, type, placement,
1078                                    page_alignment, &ctx, sg, resv, destroy);
1079         if (ret)
1080                 return ret;
1081
1082         if (!resv)
1083                 ttm_bo_unreserve(bo);
1084
1085         return 0;
1086 }
1087 EXPORT_SYMBOL(ttm_bo_init);
1088
1089 /*
1090  * buffer object vm functions.
1091  */
1092
1093 void ttm_bo_unmap_virtual(struct ttm_buffer_object *bo)
1094 {
1095         struct ttm_device *bdev = bo->bdev;
1096
1097         drm_vma_node_unmap(&bo->base.vma_node, bdev->dev_mapping);
1098         ttm_mem_io_free(bdev, bo->resource);
1099 }
1100 EXPORT_SYMBOL(ttm_bo_unmap_virtual);
1101
1102 int ttm_bo_wait(struct ttm_buffer_object *bo,
1103                 bool interruptible, bool no_wait)
1104 {
1105         long timeout = 15 * HZ;
1106
1107         if (no_wait) {
1108                 if (dma_resv_test_signaled(bo->base.resv, true))
1109                         return 0;
1110                 else
1111                         return -EBUSY;
1112         }
1113
1114         timeout = dma_resv_wait_timeout(bo->base.resv, true, interruptible,
1115                                         timeout);
1116         if (timeout < 0)
1117                 return timeout;
1118
1119         if (timeout == 0)
1120                 return -EBUSY;
1121
1122         dma_resv_add_excl_fence(bo->base.resv, NULL);
1123         return 0;
1124 }
1125 EXPORT_SYMBOL(ttm_bo_wait);
1126
1127 int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx,
1128                    gfp_t gfp_flags)
1129 {
1130         struct ttm_place place;
1131         bool locked;
1132         int ret;
1133
1134         /*
1135          * While the bo may already reside in SYSTEM placement, set
1136          * SYSTEM as new placement to cover also the move further below.
1137          * The driver may use the fact that we're moving from SYSTEM
1138          * as an indication that we're about to swap out.
1139          */
1140         memset(&place, 0, sizeof(place));
1141         place.mem_type = TTM_PL_SYSTEM;
1142         if (!ttm_bo_evict_swapout_allowable(bo, ctx, &place, &locked, NULL))
1143                 return -EBUSY;
1144
1145         if (!bo->ttm || !ttm_tt_is_populated(bo->ttm) ||
1146             bo->ttm->page_flags & TTM_PAGE_FLAG_SG ||
1147             bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED ||
1148             !ttm_bo_get_unless_zero(bo)) {
1149                 if (locked)
1150                         dma_resv_unlock(bo->base.resv);
1151                 return -EBUSY;
1152         }
1153
1154         if (bo->deleted) {
1155                 ttm_bo_cleanup_refs(bo, false, false, locked);
1156                 ttm_bo_put(bo);
1157                 return 0;
1158         }
1159
1160         ttm_bo_del_from_lru(bo);
1161         /* TODO: Cleanup the locking */
1162         spin_unlock(&bo->bdev->lru_lock);
1163
1164         /*
1165          * Move to system cached
1166          */
1167         if (bo->resource->mem_type != TTM_PL_SYSTEM) {
1168                 struct ttm_operation_ctx ctx = { false, false };
1169                 struct ttm_resource *evict_mem;
1170                 struct ttm_place hop;
1171
1172                 memset(&hop, 0, sizeof(hop));
1173                 ret = ttm_resource_alloc(bo, &place, &evict_mem);
1174                 if (unlikely(ret))
1175                         goto out;
1176
1177                 ret = ttm_bo_handle_move_mem(bo, evict_mem, true, &ctx, &hop);
1178                 if (unlikely(ret != 0)) {
1179                         WARN(ret == -EMULTIHOP, "Unexpected multihop in swaput - likely driver bug.\n");
1180                         goto out;
1181                 }
1182         }
1183
1184         /*
1185          * Make sure BO is idle.
1186          */
1187         ret = ttm_bo_wait(bo, false, false);
1188         if (unlikely(ret != 0))
1189                 goto out;
1190
1191         ttm_bo_unmap_virtual(bo);
1192
1193         /*
1194          * Swap out. Buffer will be swapped in again as soon as
1195          * anyone tries to access a ttm page.
1196          */
1197         if (bo->bdev->funcs->swap_notify)
1198                 bo->bdev->funcs->swap_notify(bo);
1199
1200         if (ttm_tt_is_populated(bo->ttm))
1201                 ret = ttm_tt_swapout(bo->bdev, bo->ttm, gfp_flags);
1202 out:
1203
1204         /*
1205          * Unreserve without putting on LRU to avoid swapping out an
1206          * already swapped buffer.
1207          */
1208         if (locked)
1209                 dma_resv_unlock(bo->base.resv);
1210         ttm_bo_put(bo);
1211         return ret;
1212 }
1213
1214 void ttm_bo_tt_destroy(struct ttm_buffer_object *bo)
1215 {
1216         if (bo->ttm == NULL)
1217                 return;
1218
1219         ttm_tt_destroy(bo->bdev, bo->ttm);
1220         bo->ttm = NULL;
1221 }