drivers/gpu/drm/qxl/qxl_cmd.c

   1 /*
   2  * Copyright 2013 Red Hat Inc.
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  20  * OTHER DEALINGS IN THE SOFTWARE.
  21  *
  22  * Authors: Dave Airlie
  23  *          Alon Levy
  24  */
  25
  26 /* QXL cmd/ring handling */
  27
  28 #include "qxl_drv.h"
  29 #include "qxl_object.h"
  30
  31 static int qxl_reap_surface_id(struct qxl_device *qdev, int max_to_reap);
  32
  33 struct ring {
  34         struct qxl_ring_header      header;
  35         uint8_t                     elements[0];
  36 };
  37
  38 struct qxl_ring {
  39         struct ring            *ring;
  40         int                     element_size;
  41         int                     n_elements;
  42         int                     prod_notify;
  43         wait_queue_head_t      *push_event;
  44         spinlock_t             lock;
  45 };
  46
  47 void qxl_ring_free(struct qxl_ring *ring)
  48 {
  49         kfree(ring);
  50 }
  51
  52 struct qxl_ring *
  53 qxl_ring_create(struct qxl_ring_header *header,
  54                 int element_size,
  55                 int n_elements,
  56                 int prod_notify,
  57                 bool set_prod_notify,
  58                 wait_queue_head_t *push_event)
  59 {
  60         struct qxl_ring *ring;
  61
  62         ring = kmalloc(sizeof(*ring), GFP_KERNEL);
  63         if (!ring)
  64                 return NULL;
  65
  66         ring->ring = (struct ring *)header;
  67         ring->element_size = element_size;
  68         ring->n_elements = n_elements;
  69         ring->prod_notify = prod_notify;
  70         ring->push_event = push_event;
  71         if (set_prod_notify)
  72                 header->notify_on_prod = ring->n_elements;
  73         spin_lock_init(&ring->lock);
  74         return ring;
  75 }
  76
  77 static int qxl_check_header(struct qxl_ring *ring)
  78 {
  79         int ret;
  80         struct qxl_ring_header *header = &(ring->ring->header);
  81         unsigned long flags;
  82         spin_lock_irqsave(&ring->lock, flags);
  83         ret = header->prod - header->cons < header->num_items;
  84         if (ret == 0)
  85                 header->notify_on_cons = header->cons + 1;
  86         spin_unlock_irqrestore(&ring->lock, flags);
  87         return ret;
  88 }
  89
  90 static int qxl_check_idle(struct qxl_ring *ring)
  91 {
  92         int ret;
  93         struct qxl_ring_header *header = &(ring->ring->header);
  94         unsigned long flags;
  95         spin_lock_irqsave(&ring->lock, flags);
  96         ret = header->prod == header->cons;
  97         spin_unlock_irqrestore(&ring->lock, flags);
  98         return ret;
  99 }
 100
 101 int qxl_ring_push(struct qxl_ring *ring,
 102                   const void *new_elt, bool interruptible)
 103 {
 104         struct qxl_ring_header *header = &(ring->ring->header);
 105         uint8_t *elt;
 106         int idx, ret;
 107         unsigned long flags;
 108         spin_lock_irqsave(&ring->lock, flags);
 109         if (header->prod - header->cons == header->num_items) {
 110                 header->notify_on_cons = header->cons + 1;
 111                 mb();
 112                 spin_unlock_irqrestore(&ring->lock, flags);
 113                 if (!drm_can_sleep()) {
 114                         while (!qxl_check_header(ring))
 115                                 udelay(1);
 116                 } else {
 117                         if (interruptible) {
 118                                 ret = wait_event_interruptible(*ring->push_event,
 119                                                                qxl_check_header(ring));
 120                                 if (ret)
 121                                         return ret;
 122                         } else {
 123                                 wait_event(*ring->push_event,
 124                                            qxl_check_header(ring));
 125                         }
 126
 127                 }
 128                 spin_lock_irqsave(&ring->lock, flags);
 129         }
 130
 131         idx = header->prod & (ring->n_elements - 1);
 132         elt = ring->ring->elements + idx * ring->element_size;
 133
 134         memcpy((void *)elt, new_elt, ring->element_size);
 135
 136         header->prod++;
 137
 138         mb();
 139
 140         if (header->prod == header->notify_on_prod)
 141                 outb(0, ring->prod_notify);
 142
 143         spin_unlock_irqrestore(&ring->lock, flags);
 144         return 0;
 145 }
 146
 147 static bool qxl_ring_pop(struct qxl_ring *ring,
 148                          void *element)
 149 {
 150         volatile struct qxl_ring_header *header = &(ring->ring->header);
 151         volatile uint8_t *ring_elt;
 152         int idx;
 153         unsigned long flags;
 154         spin_lock_irqsave(&ring->lock, flags);
 155         if (header->cons == header->prod) {
 156                 header->notify_on_prod = header->cons + 1;
 157                 spin_unlock_irqrestore(&ring->lock, flags);
 158                 return false;
 159         }
 160
 161         idx = header->cons & (ring->n_elements - 1);
 162         ring_elt = ring->ring->elements + idx * ring->element_size;
 163
 164         memcpy(element, (void *)ring_elt, ring->element_size);
 165
 166         header->cons++;
 167
 168         spin_unlock_irqrestore(&ring->lock, flags);
 169         return true;
 170 }
 171
 172 int
 173 qxl_push_command_ring_release(struct qxl_device *qdev, struct qxl_release *release,
 174                               uint32_t type, bool interruptible)
 175 {
 176         struct qxl_command cmd;
 177
 178         cmd.type = type;
 179         cmd.data = qxl_bo_physical_address(qdev, release->bos[0], release->release_offset);
 180
 181         return qxl_ring_push(qdev->command_ring, &cmd, interruptible);
 182 }
 183
 184 int
 185 qxl_push_cursor_ring_release(struct qxl_device *qdev, struct qxl_release *release,
 186                              uint32_t type, bool interruptible)
 187 {
 188         struct qxl_command cmd;
 189
 190         cmd.type = type;
 191         cmd.data = qxl_bo_physical_address(qdev, release->bos[0], release->release_offset);
 192
 193         return qxl_ring_push(qdev->cursor_ring, &cmd, interruptible);
 194 }
 195
 196 bool qxl_queue_garbage_collect(struct qxl_device *qdev, bool flush)
 197 {
 198         if (!qxl_check_idle(qdev->release_ring)) {
 199                 queue_work(qdev->gc_queue, &qdev->gc_work);
 200                 if (flush)
 201                         flush_work(&qdev->gc_work);
 202                 return true;
 203         }
 204         return false;
 205 }
 206
 207 int qxl_garbage_collect(struct qxl_device *qdev)
 208 {
 209         struct qxl_release *release;
 210         uint64_t id, next_id;
 211         int i = 0;
 212         int ret;
 213         union qxl_release_info *info;
 214
 215         while (qxl_ring_pop(qdev->release_ring, &id)) {
 216                 QXL_INFO(qdev, "popped %lld\n", id);
 217                 while (id) {
 218                         release = qxl_release_from_id_locked(qdev, id);
 219                         if (release == NULL)
 220                                 break;
 221
 222                         ret = qxl_release_reserve(qdev, release, false);
 223                         if (ret) {
 224                                 qxl_io_log(qdev, "failed to reserve release on garbage collect %lld\n", id);
 225                                 DRM_ERROR("failed to reserve release %lld\n", id);
 226                         }
 227
 228                         info = qxl_release_map(qdev, release);
 229                         next_id = info->next;
 230                         qxl_release_unmap(qdev, release, info);
 231
 232                         qxl_release_unreserve(qdev, release);
 233                         QXL_INFO(qdev, "popped %lld, next %lld\n", id,
 234                                 next_id);
 235
 236                         switch (release->type) {
 237                         case QXL_RELEASE_DRAWABLE:
 238                         case QXL_RELEASE_SURFACE_CMD:
 239                         case QXL_RELEASE_CURSOR_CMD:
 240                                 break;
 241                         default:
 242                                 DRM_ERROR("unexpected release type\n");
 243                                 break;
 244                         }
 245                         id = next_id;
 246
 247                         qxl_release_free(qdev, release);
 248                         ++i;
 249                 }
 250         }
 251
 252         QXL_INFO(qdev, "%s: %lld\n", __func__, i);
 253
 254         return i;
 255 }
 256
 257 int qxl_alloc_bo_reserved(struct qxl_device *qdev, unsigned long size,
 258                           struct qxl_bo **_bo)
 259 {
 260         struct qxl_bo *bo;
 261         int ret;
 262
 263         ret = qxl_bo_create(qdev, size, false /* not kernel - device */,
 264                             QXL_GEM_DOMAIN_VRAM, NULL, &bo);
 265         if (ret) {
 266                 DRM_ERROR("failed to allocate VRAM BO\n");
 267                 return ret;
 268         }
 269         ret = qxl_bo_reserve(bo, false);
 270         if (unlikely(ret != 0))
 271                 goto out_unref;
 272
 273         *_bo = bo;
 274         return 0;
 275 out_unref:
 276         qxl_bo_unref(&bo);
 277         return 0;
 278 }
 279
 280 static int wait_for_io_cmd_user(struct qxl_device *qdev, uint8_t val, long port, bool intr)
 281 {
 282         int irq_num;
 283         long addr = qdev->io_base + port;
 284         int ret;
 285
 286         mutex_lock(&qdev->async_io_mutex);
 287         irq_num = atomic_read(&qdev->irq_received_io_cmd);
 288         if (qdev->last_sent_io_cmd > irq_num) {
 289                 if (intr)
 290                         ret = wait_event_interruptible_timeout(qdev->io_cmd_event,
 291                                                                atomic_read(&qdev->irq_received_io_cmd) > irq_num, 5*HZ);
 292                 else
 293                         ret = wait_event_timeout(qdev->io_cmd_event,
 294                                                  atomic_read(&qdev->irq_received_io_cmd) > irq_num, 5*HZ);
 295                 /* 0 is timeout, just bail the "hw" has gone away */
 296                 if (ret <= 0)
 297                         goto out;
 298                 irq_num = atomic_read(&qdev->irq_received_io_cmd);
 299         }
 300         outb(val, addr);
 301         qdev->last_sent_io_cmd = irq_num + 1;
 302         if (intr)
 303                 ret = wait_event_interruptible_timeout(qdev->io_cmd_event,
 304                                                        atomic_read(&qdev->irq_received_io_cmd) > irq_num, 5*HZ);
 305         else
 306                 ret = wait_event_timeout(qdev->io_cmd_event,
 307                                          atomic_read(&qdev->irq_received_io_cmd) > irq_num, 5*HZ);
 308 out:
 309         if (ret > 0)
 310                 ret = 0;
 311         mutex_unlock(&qdev->async_io_mutex);
 312         return ret;
 313 }
 314
 315 static void wait_for_io_cmd(struct qxl_device *qdev, uint8_t val, long port)
 316 {
 317         int ret;
 318
 319 restart:
 320         ret = wait_for_io_cmd_user(qdev, val, port, false);
 321         if (ret == -ERESTARTSYS)
 322                 goto restart;
 323 }
 324
 325 int qxl_io_update_area(struct qxl_device *qdev, struct qxl_bo *surf,
 326                         const struct qxl_rect *area)
 327 {
 328         int surface_id;
 329         uint32_t surface_width, surface_height;
 330         int ret;
 331
 332         if (!surf->hw_surf_alloc)
 333                 DRM_ERROR("got io update area with no hw surface\n");
 334
 335         if (surf->is_primary)
 336                 surface_id = 0;
 337         else
 338                 surface_id = surf->surface_id;
 339         surface_width = surf->surf.width;
 340         surface_height = surf->surf.height;
 341
 342         if (area->left < 0 || area->top < 0 ||
 343             area->right > surface_width || area->bottom > surface_height) {
 344                 qxl_io_log(qdev, "%s: not doing area update for "
 345                            "%d, (%d,%d,%d,%d) (%d,%d)\n", __func__, surface_id, area->left,
 346                            area->top, area->right, area->bottom, surface_width, surface_height);
 347                 return -EINVAL;
 348         }
 349         mutex_lock(&qdev->update_area_mutex);
 350         qdev->ram_header->update_area = *area;
 351         qdev->ram_header->update_surface = surface_id;
 352         ret = wait_for_io_cmd_user(qdev, 0, QXL_IO_UPDATE_AREA_ASYNC, true);
 353         mutex_unlock(&qdev->update_area_mutex);
 354         return ret;
 355 }
 356
 357 void qxl_io_notify_oom(struct qxl_device *qdev)
 358 {
 359         outb(0, qdev->io_base + QXL_IO_NOTIFY_OOM);
 360 }
 361
 362 void qxl_io_flush_release(struct qxl_device *qdev)
 363 {
 364         outb(0, qdev->io_base + QXL_IO_FLUSH_RELEASE);
 365 }
 366
 367 void qxl_io_flush_surfaces(struct qxl_device *qdev)
 368 {
 369         wait_for_io_cmd(qdev, 0, QXL_IO_FLUSH_SURFACES_ASYNC);
 370 }
 371
 372
 373 void qxl_io_destroy_primary(struct qxl_device *qdev)
 374 {
 375         wait_for_io_cmd(qdev, 0, QXL_IO_DESTROY_PRIMARY_ASYNC);
 376 }
 377
 378 void qxl_io_create_primary(struct qxl_device *qdev, unsigned width,
 379                            unsigned height, unsigned offset, struct qxl_bo *bo)
 380 {
 381         struct qxl_surface_create *create;
 382
 383         QXL_INFO(qdev, "%s: qdev %p, ram_header %p\n", __func__, qdev,
 384                  qdev->ram_header);
 385         create = &qdev->ram_header->create_surface;
 386         create->format = bo->surf.format;
 387         create->width = width;
 388         create->height = height;
 389         create->stride = bo->surf.stride;
 390         create->mem = qxl_bo_physical_address(qdev, bo, offset);
 391
 392         QXL_INFO(qdev, "%s: mem = %llx, from %p\n", __func__, create->mem,
 393                  bo->kptr);
 394
 395         create->flags = QXL_SURF_FLAG_KEEP_DATA;
 396         create->type = QXL_SURF_TYPE_PRIMARY;
 397
 398         wait_for_io_cmd(qdev, 0, QXL_IO_CREATE_PRIMARY_ASYNC);
 399 }
 400
 401 void qxl_io_memslot_add(struct qxl_device *qdev, uint8_t id)
 402 {
 403         QXL_INFO(qdev, "qxl_memslot_add %d\n", id);
 404         wait_for_io_cmd(qdev, id, QXL_IO_MEMSLOT_ADD_ASYNC);
 405 }
 406
 407 void qxl_io_log(struct qxl_device *qdev, const char *fmt, ...)
 408 {
 409         va_list args;
 410
 411         va_start(args, fmt);
 412         vsnprintf(qdev->ram_header->log_buf, QXL_LOG_BUF_SIZE, fmt, args);
 413         va_end(args);
 414         /*
 415          * DO not do a DRM output here - this will call printk, which will
 416          * call back into qxl for rendering (qxl_fb)
 417          */
 418         outb(0, qdev->io_base + QXL_IO_LOG);
 419 }
 420
 421 void qxl_io_reset(struct qxl_device *qdev)
 422 {
 423         outb(0, qdev->io_base + QXL_IO_RESET);
 424 }
 425
 426 void qxl_io_monitors_config(struct qxl_device *qdev)
 427 {
 428         qxl_io_log(qdev, "%s: %d [%dx%d+%d+%d]\n", __func__,
 429                    qdev->monitors_config ?
 430                    qdev->monitors_config->count : -1,
 431                    qdev->monitors_config && qdev->monitors_config->count ?
 432                    qdev->monitors_config->heads[0].width : -1,
 433                    qdev->monitors_config && qdev->monitors_config->count ?
 434                    qdev->monitors_config->heads[0].height : -1,
 435                    qdev->monitors_config && qdev->monitors_config->count ?
 436                    qdev->monitors_config->heads[0].x : -1,
 437                    qdev->monitors_config && qdev->monitors_config->count ?
 438                    qdev->monitors_config->heads[0].y : -1
 439                    );
 440
 441         wait_for_io_cmd(qdev, 0, QXL_IO_MONITORS_CONFIG_ASYNC);
 442 }
 443
 444 int qxl_surface_id_alloc(struct qxl_device *qdev,
 445                       struct qxl_bo *surf)
 446 {
 447         uint32_t handle;
 448         int idr_ret;
 449         int count = 0;
 450 again:
 451         idr_preload(GFP_ATOMIC);
 452         spin_lock(&qdev->surf_id_idr_lock);
 453         idr_ret = idr_alloc(&qdev->surf_id_idr, NULL, 1, 0, GFP_NOWAIT);
 454         spin_unlock(&qdev->surf_id_idr_lock);
 455         idr_preload_end();
 456         if (idr_ret < 0)
 457                 return idr_ret;
 458         handle = idr_ret;
 459
 460         if (handle >= qdev->rom->n_surfaces) {
 461                 count++;
 462                 spin_lock(&qdev->surf_id_idr_lock);
 463                 idr_remove(&qdev->surf_id_idr, handle);
 464                 spin_unlock(&qdev->surf_id_idr_lock);
 465                 qxl_reap_surface_id(qdev, 2);
 466                 goto again;
 467         }
 468         surf->surface_id = handle;
 469
 470         spin_lock(&qdev->surf_id_idr_lock);
 471         qdev->last_alloced_surf_id = handle;
 472         spin_unlock(&qdev->surf_id_idr_lock);
 473         return 0;
 474 }
 475
 476 void qxl_surface_id_dealloc(struct qxl_device *qdev,
 477                             uint32_t surface_id)
 478 {
 479         spin_lock(&qdev->surf_id_idr_lock);
 480         idr_remove(&qdev->surf_id_idr, surface_id);
 481         spin_unlock(&qdev->surf_id_idr_lock);
 482 }
 483
 484 int qxl_hw_surface_alloc(struct qxl_device *qdev,
 485                          struct qxl_bo *surf,
 486                          struct ttm_mem_reg *new_mem)
 487 {
 488         struct qxl_surface_cmd *cmd;
 489         struct qxl_release *release;
 490         int ret;
 491
 492         if (surf->hw_surf_alloc)
 493                 return 0;
 494
 495         ret = qxl_alloc_surface_release_reserved(qdev, QXL_SURFACE_CMD_CREATE,
 496                                                  NULL,
 497                                                  &release);
 498         if (ret)
 499                 return ret;
 500
 501         cmd = (struct qxl_surface_cmd *)qxl_release_map(qdev, release);
 502         cmd->type = QXL_SURFACE_CMD_CREATE;
 503         cmd->u.surface_create.format = surf->surf.format;
 504         cmd->u.surface_create.width = surf->surf.width;
 505         cmd->u.surface_create.height = surf->surf.height;
 506         cmd->u.surface_create.stride = surf->surf.stride;
 507         if (new_mem) {
 508                 int slot_id = surf->type == QXL_GEM_DOMAIN_VRAM ? qdev->main_mem_slot : qdev->surfaces_mem_slot;
 509                 struct qxl_memslot *slot = &(qdev->mem_slots[slot_id]);
 510
 511                 /* TODO - need to hold one of the locks to read tbo.offset */
 512                 cmd->u.surface_create.data = slot->high_bits;
 513
 514                 cmd->u.surface_create.data |= (new_mem->start << PAGE_SHIFT) + surf->tbo.bdev->man[new_mem->mem_type].gpu_offset;
 515         } else
 516                 cmd->u.surface_create.data = qxl_bo_physical_address(qdev, surf, 0);
 517         cmd->surface_id = surf->surface_id;
 518         qxl_release_unmap(qdev, release, &cmd->release_info);
 519
 520         surf->surf_create = release;
 521
 522         /* no need to add a release to the fence for this bo,
 523            since it is only released when we ask to destroy the surface
 524            and it would never signal otherwise */
 525         qxl_fence_releaseable(qdev, release);
 526
 527         qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false);
 528
 529         qxl_release_unreserve(qdev, release);
 530
 531         surf->hw_surf_alloc = true;
 532         spin_lock(&qdev->surf_id_idr_lock);
 533         idr_replace(&qdev->surf_id_idr, surf, surf->surface_id);
 534         spin_unlock(&qdev->surf_id_idr_lock);
 535         return 0;
 536 }
 537
 538 int qxl_hw_surface_dealloc(struct qxl_device *qdev,
 539                            struct qxl_bo *surf)
 540 {
 541         struct qxl_surface_cmd *cmd;
 542         struct qxl_release *release;
 543         int ret;
 544         int id;
 545
 546         if (!surf->hw_surf_alloc)
 547                 return 0;
 548
 549         ret = qxl_alloc_surface_release_reserved(qdev, QXL_SURFACE_CMD_DESTROY,
 550                                                  surf->surf_create,
 551                                                  &release);
 552         if (ret)
 553                 return ret;
 554
 555         surf->surf_create = NULL;
 556         /* remove the surface from the idr, but not the surface id yet */
 557         spin_lock(&qdev->surf_id_idr_lock);
 558         idr_replace(&qdev->surf_id_idr, NULL, surf->surface_id);
 559         spin_unlock(&qdev->surf_id_idr_lock);
 560         surf->hw_surf_alloc = false;
 561
 562         id = surf->surface_id;
 563         surf->surface_id = 0;
 564
 565         release->surface_release_id = id;
 566         cmd = (struct qxl_surface_cmd *)qxl_release_map(qdev, release);
 567         cmd->type = QXL_SURFACE_CMD_DESTROY;
 568         cmd->surface_id = id;
 569         qxl_release_unmap(qdev, release, &cmd->release_info);
 570
 571         qxl_fence_releaseable(qdev, release);
 572
 573         qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false);
 574
 575         qxl_release_unreserve(qdev, release);
 576
 577
 578         return 0;
 579 }
 580
 581 int qxl_update_surface(struct qxl_device *qdev, struct qxl_bo *surf)
 582 {
 583         struct qxl_rect rect;
 584         int ret;
 585
 586         /* if we are evicting, we need to make sure the surface is up
 587            to date */
 588         rect.left = 0;
 589         rect.right = surf->surf.width;
 590         rect.top = 0;
 591         rect.bottom = surf->surf.height;
 592 retry:
 593         ret = qxl_io_update_area(qdev, surf, &rect);
 594         if (ret == -ERESTARTSYS)
 595                 goto retry;
 596         return ret;
 597 }
 598
 599 static void qxl_surface_evict_locked(struct qxl_device *qdev, struct qxl_bo *surf, bool do_update_area)
 600 {
 601         /* no need to update area if we are just freeing the surface normally */
 602         if (do_update_area)
 603                 qxl_update_surface(qdev, surf);
 604
 605         /* nuke the surface id at the hw */
 606         qxl_hw_surface_dealloc(qdev, surf);
 607 }
 608
 609 void qxl_surface_evict(struct qxl_device *qdev, struct qxl_bo *surf, bool do_update_area)
 610 {
 611         mutex_lock(&qdev->surf_evict_mutex);
 612         qxl_surface_evict_locked(qdev, surf, do_update_area);
 613         mutex_unlock(&qdev->surf_evict_mutex);
 614 }
 615
 616 static int qxl_reap_surf(struct qxl_device *qdev, struct qxl_bo *surf, bool stall)
 617 {
 618         int ret;
 619
 620         ret = qxl_bo_reserve(surf, false);
 621         if (ret == -EBUSY)
 622                 return -EBUSY;
 623
 624         if (surf->fence.num_active_releases > 0 && stall == false) {
 625                 qxl_bo_unreserve(surf);
 626                 return -EBUSY;
 627         }
 628
 629         if (stall)
 630                 mutex_unlock(&qdev->surf_evict_mutex);
 631
 632         spin_lock(&surf->tbo.bdev->fence_lock);
 633         ret = ttm_bo_wait(&surf->tbo, true, true, !stall);
 634         spin_unlock(&surf->tbo.bdev->fence_lock);
 635
 636         if (stall)
 637                 mutex_lock(&qdev->surf_evict_mutex);
 638         if (ret == -EBUSY) {
 639                 qxl_bo_unreserve(surf);
 640                 return -EBUSY;
 641         }
 642
 643         qxl_surface_evict_locked(qdev, surf, true);
 644         qxl_bo_unreserve(surf);
 645         return 0;
 646 }
 647
 648 static int qxl_reap_surface_id(struct qxl_device *qdev, int max_to_reap)
 649 {
 650         int num_reaped = 0;
 651         int i, ret;
 652         bool stall = false;
 653         int start = 0;
 654
 655         mutex_lock(&qdev->surf_evict_mutex);
 656 again:
 657
 658         spin_lock(&qdev->surf_id_idr_lock);
 659         start = qdev->last_alloced_surf_id + 1;
 660         spin_unlock(&qdev->surf_id_idr_lock);
 661
 662         for (i = start; i < start + qdev->rom->n_surfaces; i++) {
 663                 void *objptr;
 664                 int surfid = i % qdev->rom->n_surfaces;
 665
 666                 /* this avoids the case where the objects is in the
 667                    idr but has been evicted half way - its makes
 668                    the idr lookup atomic with the eviction */
 669                 spin_lock(&qdev->surf_id_idr_lock);
 670                 objptr = idr_find(&qdev->surf_id_idr, surfid);
 671                 spin_unlock(&qdev->surf_id_idr_lock);
 672
 673                 if (!objptr)
 674                         continue;
 675
 676                 ret = qxl_reap_surf(qdev, objptr, stall);
 677                 if (ret == 0)
 678                         num_reaped++;
 679                 if (num_reaped >= max_to_reap)
 680                         break;
 681         }
 682         if (num_reaped == 0 && stall == false) {
 683                 stall = true;
 684                 goto again;
 685         }
 686
 687         mutex_unlock(&qdev->surf_evict_mutex);
 688         if (num_reaped) {
 689                 usleep_range(500, 1000);
 690                 qxl_queue_garbage_collect(qdev, true);
 691         }
 692
 693         return 0;
 694 }