kernel/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 void qxl_ring_init_hdr(struct qxl_ring *ring)
  53 {
  54         ring->ring->header.notify_on_prod = ring->n_elements;
  55 }
  56
  57 struct qxl_ring *
  58 qxl_ring_create(struct qxl_ring_header *header,
  59                 int element_size,
  60                 int n_elements,
  61                 int prod_notify,
  62                 bool set_prod_notify,
  63                 wait_queue_head_t *push_event)
  64 {
  65         struct qxl_ring *ring;
  66
  67         ring = kmalloc(sizeof(*ring), GFP_KERNEL);
  68         if (!ring)
  69                 return NULL;
  70
  71         ring->ring = (struct ring *)header;
  72         ring->element_size = element_size;
  73         ring->n_elements = n_elements;
  74         ring->prod_notify = prod_notify;
  75         ring->push_event = push_event;
  76         if (set_prod_notify)
  77                 qxl_ring_init_hdr(ring);
  78         spin_lock_init(&ring->lock);
  79         return ring;
  80 }
  81
  82 static int qxl_check_header(struct qxl_ring *ring)
  83 {
  84         int ret;
  85         struct qxl_ring_header *header = &(ring->ring->header);
  86         unsigned long flags;
  87         spin_lock_irqsave(&ring->lock, flags);
  88         ret = header->prod - header->cons < header->num_items;
  89         if (ret == 0)
  90                 header->notify_on_cons = header->cons + 1;
  91         spin_unlock_irqrestore(&ring->lock, flags);
  92         return ret;
  93 }
  94
  95 int qxl_check_idle(struct qxl_ring *ring)
  96 {
  97         int ret;
  98         struct qxl_ring_header *header = &(ring->ring->header);
  99         unsigned long flags;
 100         spin_lock_irqsave(&ring->lock, flags);
 101         ret = header->prod == header->cons;
 102         spin_unlock_irqrestore(&ring->lock, flags);
 103         return ret;
 104 }
 105
 106 int qxl_ring_push(struct qxl_ring *ring,
 107                   const void *new_elt, bool interruptible)
 108 {
 109         struct qxl_ring_header *header = &(ring->ring->header);
 110         uint8_t *elt;
 111         int idx, ret;
 112         unsigned long flags;
 113         spin_lock_irqsave(&ring->lock, flags);
 114         if (header->prod - header->cons == header->num_items) {
 115                 header->notify_on_cons = header->cons + 1;
 116                 mb();
 117                 spin_unlock_irqrestore(&ring->lock, flags);
 118                 if (!drm_can_sleep()) {
 119                         while (!qxl_check_header(ring))
 120                                 udelay(1);
 121                 } else {
 122                         if (interruptible) {
 123                                 ret = wait_event_interruptible(*ring->push_event,
 124                                                                qxl_check_header(ring));
 125                                 if (ret)
 126                                         return ret;
 127                         } else {
 128                                 wait_event(*ring->push_event,
 129                                            qxl_check_header(ring));
 130                         }
 131
 132                 }
 133                 spin_lock_irqsave(&ring->lock, flags);
 134         }
 135
 136         idx = header->prod & (ring->n_elements - 1);
 137         elt = ring->ring->elements + idx * ring->element_size;
 138
 139         memcpy((void *)elt, new_elt, ring->element_size);
 140
 141         header->prod++;
 142
 143         mb();
 144
 145         if (header->prod == header->notify_on_prod)
 146                 outb(0, ring->prod_notify);
 147
 148         spin_unlock_irqrestore(&ring->lock, flags);
 149         return 0;
 150 }
 151
 152 static bool qxl_ring_pop(struct qxl_ring *ring,
 153                          void *element)
 154 {
 155         volatile struct qxl_ring_header *header = &(ring->ring->header);
 156         volatile uint8_t *ring_elt;
 157         int idx;
 158         unsigned long flags;
 159         spin_lock_irqsave(&ring->lock, flags);
 160         if (header->cons == header->prod) {
 161                 header->notify_on_prod = header->cons + 1;
 162                 spin_unlock_irqrestore(&ring->lock, flags);
 163                 return false;
 164         }
 165
 166         idx = header->cons & (ring->n_elements - 1);
 167         ring_elt = ring->ring->elements + idx * ring->element_size;
 168
 169         memcpy(element, (void *)ring_elt, ring->element_size);
 170
 171         header->cons++;
 172
 173         spin_unlock_irqrestore(&ring->lock, flags);
 174         return true;
 175 }
 176
 177 int
 178 qxl_push_command_ring_release(struct qxl_device *qdev, struct qxl_release *release,
 179                               uint32_t type, bool interruptible)
 180 {
 181         struct qxl_command cmd;
 182         struct qxl_bo_list *entry = list_first_entry(&release->bos, struct qxl_bo_list, tv.head);
 183
 184         cmd.type = type;
 185         cmd.data = qxl_bo_physical_address(qdev, to_qxl_bo(entry->tv.bo), release->release_offset);
 186
 187         return qxl_ring_push(qdev->command_ring, &cmd, interruptible);
 188 }
 189
 190 int
 191 qxl_push_cursor_ring_release(struct qxl_device *qdev, struct qxl_release *release,
 192                              uint32_t type, bool interruptible)
 193 {
 194         struct qxl_command cmd;
 195         struct qxl_bo_list *entry = list_first_entry(&release->bos, struct qxl_bo_list, tv.head);
 196
 197         cmd.type = type;
 198         cmd.data = qxl_bo_physical_address(qdev, to_qxl_bo(entry->tv.bo), release->release_offset);
 199
 200         return qxl_ring_push(qdev->cursor_ring, &cmd, interruptible);
 201 }
 202
 203 bool qxl_queue_garbage_collect(struct qxl_device *qdev, bool flush)
 204 {
 205         if (!qxl_check_idle(qdev->release_ring)) {
 206                 queue_work(qdev->gc_queue, &qdev->gc_work);
 207                 if (flush)
 208                         flush_work(&qdev->gc_work);
 209                 return true;
 210         }
 211         return false;
 212 }
 213
 214 int qxl_garbage_collect(struct qxl_device *qdev)
 215 {
 216         struct qxl_release *release;
 217         uint64_t id, next_id;
 218         int i = 0;
 219         union qxl_release_info *info;
 220
 221         while (qxl_ring_pop(qdev->release_ring, &id)) {
 222                 QXL_INFO(qdev, "popped %lld\n", id);
 223                 while (id) {
 224                         release = qxl_release_from_id_locked(qdev, id);
 225                         if (release == NULL)
 226                                 break;
 227
 228                         info = qxl_release_map(qdev, release);
 229                         next_id = info->next;
 230                         qxl_release_unmap(qdev, release, info);
 231
 232                         QXL_INFO(qdev, "popped %lld, next %lld\n", id,
 233                                 next_id);
 234
 235                         switch (release->type) {
 236                         case QXL_RELEASE_DRAWABLE:
 237                         case QXL_RELEASE_SURFACE_CMD:
 238                         case QXL_RELEASE_CURSOR_CMD:
 239                                 break;
 240                         default:
 241                                 DRM_ERROR("unexpected release type\n");
 242                                 break;
 243                         }
 244                         id = next_id;
 245
 246                         qxl_release_free(qdev, release);
 247                         ++i;
 248                 }
 249         }
 250
 251         QXL_INFO(qdev, "%s: %lld\n", __func__, i);
 252
 253         return i;
 254 }
 255
 256 int qxl_alloc_bo_reserved(struct qxl_device *qdev,
 257                           struct qxl_release *release,
 258                           unsigned long size,
 259                           struct qxl_bo **_bo)
 260 {
 261         struct qxl_bo *bo;
 262         int ret;
 263
 264         ret = qxl_bo_create(qdev, size, false /* not kernel - device */,
 265                             false, QXL_GEM_DOMAIN_VRAM, NULL, &bo);
 266         if (ret) {
 267                 DRM_ERROR("failed to allocate VRAM BO\n");
 268                 return ret;
 269         }
 270         ret = qxl_release_list_add(release, bo);
 271         if (ret)
 272                 goto out_unref;
 273
 274         *_bo = bo;
 275         return 0;
 276 out_unref:
 277         qxl_bo_unref(&bo);
 278         return ret;
 279 }
 280
 281 static int wait_for_io_cmd_user(struct qxl_device *qdev, uint8_t val, long port, bool intr)
 282 {
 283         int irq_num;
 284         long addr = qdev->io_base + port;
 285         int ret;
 286
 287         mutex_lock(&qdev->async_io_mutex);
 288         irq_num = atomic_read(&qdev->irq_received_io_cmd);
 289         if (qdev->last_sent_io_cmd > irq_num) {
 290                 if (intr)
 291                         ret = wait_event_interruptible_timeout(qdev->io_cmd_event,
 292                                                                atomic_read(&qdev->irq_received_io_cmd) > irq_num, 5*HZ);
 293                 else
 294                         ret = wait_event_timeout(qdev->io_cmd_event,
 295                                                  atomic_read(&qdev->irq_received_io_cmd) > irq_num, 5*HZ);
 296                 /* 0 is timeout, just bail the "hw" has gone away */
 297                 if (ret <= 0)
 298                         goto out;
 299                 irq_num = atomic_read(&qdev->irq_received_io_cmd);
 300         }
 301         outb(val, addr);
 302         qdev->last_sent_io_cmd = irq_num + 1;
 303         if (intr)
 304                 ret = wait_event_interruptible_timeout(qdev->io_cmd_event,
 305                                                        atomic_read(&qdev->irq_received_io_cmd) > irq_num, 5*HZ);
 306         else
 307                 ret = wait_event_timeout(qdev->io_cmd_event,
 308                                          atomic_read(&qdev->irq_received_io_cmd) > irq_num, 5*HZ);
 309 out:
 310         if (ret > 0)
 311                 ret = 0;
 312         mutex_unlock(&qdev->async_io_mutex);
 313         return ret;
 314 }
 315
 316 static void wait_for_io_cmd(struct qxl_device *qdev, uint8_t val, long port)
 317 {
 318         int ret;
 319
 320 restart:
 321         ret = wait_for_io_cmd_user(qdev, val, port, false);
 322         if (ret == -ERESTARTSYS)
 323                 goto restart;
 324 }
 325
 326 int qxl_io_update_area(struct qxl_device *qdev, struct qxl_bo *surf,
 327                         const struct qxl_rect *area)
 328 {
 329         int surface_id;
 330         uint32_t surface_width, surface_height;
 331         int ret;
 332
 333         if (!surf->hw_surf_alloc)
 334                 DRM_ERROR("got io update area with no hw surface\n");
 335
 336         if (surf->is_primary)
 337                 surface_id = 0;
 338         else
 339                 surface_id = surf->surface_id;
 340         surface_width = surf->surf.width;
 341         surface_height = surf->surf.height;
 342
 343         if (area->left < 0 || area->top < 0 ||
 344             area->right > surface_width || area->bottom > surface_height) {
 345                 qxl_io_log(qdev, "%s: not doing area update for "
 346                            "%d, (%d,%d,%d,%d) (%d,%d)\n", __func__, surface_id, area->left,
 347                            area->top, area->right, area->bottom, surface_width, surface_height);
 348                 return -EINVAL;
 349         }
 350         mutex_lock(&qdev->update_area_mutex);
 351         qdev->ram_header->update_area = *area;
 352         qdev->ram_header->update_surface = surface_id;
 353         ret = wait_for_io_cmd_user(qdev, 0, QXL_IO_UPDATE_AREA_ASYNC, true);
 354         mutex_unlock(&qdev->update_area_mutex);
 355         return ret;
 356 }
 357
 358 void qxl_io_notify_oom(struct qxl_device *qdev)
 359 {
 360         outb(0, qdev->io_base + QXL_IO_NOTIFY_OOM);
 361 }
 362
 363 void qxl_io_flush_release(struct qxl_device *qdev)
 364 {
 365         outb(0, qdev->io_base + QXL_IO_FLUSH_RELEASE);
 366 }
 367
 368 void qxl_io_flush_surfaces(struct qxl_device *qdev)
 369 {
 370         wait_for_io_cmd(qdev, 0, QXL_IO_FLUSH_SURFACES_ASYNC);
 371 }
 372
 373
 374 void qxl_io_destroy_primary(struct qxl_device *qdev)
 375 {
 376         wait_for_io_cmd(qdev, 0, QXL_IO_DESTROY_PRIMARY_ASYNC);
 377 }
 378
 379 void qxl_io_create_primary(struct qxl_device *qdev,
 380                            unsigned offset, struct qxl_bo *bo)
 381 {
 382         struct qxl_surface_create *create;
 383
 384         QXL_INFO(qdev, "%s: qdev %p, ram_header %p\n", __func__, qdev,
 385                  qdev->ram_header);
 386         create = &qdev->ram_header->create_surface;
 387         create->format = bo->surf.format;
 388         create->width = bo->surf.width;
 389         create->height = bo->surf.height;
 390         create->stride = bo->surf.stride;
 391         create->mem = qxl_bo_physical_address(qdev, bo, offset);
 392
 393         QXL_INFO(qdev, "%s: mem = %llx, from %p\n", __func__, create->mem,
 394                  bo->kptr);
 395
 396         create->flags = QXL_SURF_FLAG_KEEP_DATA;
 397         create->type = QXL_SURF_TYPE_PRIMARY;
 398
 399         wait_for_io_cmd(qdev, 0, QXL_IO_CREATE_PRIMARY_ASYNC);
 400 }
 401
 402 void qxl_io_memslot_add(struct qxl_device *qdev, uint8_t id)
 403 {
 404         QXL_INFO(qdev, "qxl_memslot_add %d\n", id);
 405         wait_for_io_cmd(qdev, id, QXL_IO_MEMSLOT_ADD_ASYNC);
 406 }
 407
 408 void qxl_io_log(struct qxl_device *qdev, const char *fmt, ...)
 409 {
 410         va_list args;
 411
 412         va_start(args, fmt);
 413         vsnprintf(qdev->ram_header->log_buf, QXL_LOG_BUF_SIZE, fmt, args);
 414         va_end(args);
 415         /*
 416          * DO not do a DRM output here - this will call printk, which will
 417          * call back into qxl for rendering (qxl_fb)
 418          */
 419         outb(0, qdev->io_base + QXL_IO_LOG);
 420 }
 421
 422 void qxl_io_reset(struct qxl_device *qdev)
 423 {
 424         outb(0, qdev->io_base + QXL_IO_RESET);
 425 }
 426
 427 void qxl_io_monitors_config(struct qxl_device *qdev)
 428 {
 429         qxl_io_log(qdev, "%s: %d [%dx%d+%d+%d]\n", __func__,
 430                    qdev->monitors_config ?
 431                    qdev->monitors_config->count : -1,
 432                    qdev->monitors_config && qdev->monitors_config->count ?
 433                    qdev->monitors_config->heads[0].width : -1,
 434                    qdev->monitors_config && qdev->monitors_config->count ?
 435                    qdev->monitors_config->heads[0].height : -1,
 436                    qdev->monitors_config && qdev->monitors_config->count ?
 437                    qdev->monitors_config->heads[0].x : -1,
 438                    qdev->monitors_config && qdev->monitors_config->count ?
 439                    qdev->monitors_config->heads[0].y : -1
 440                    );
 441
 442         wait_for_io_cmd(qdev, 0, QXL_IO_MONITORS_CONFIG_ASYNC);
 443 }
 444
 445 int qxl_surface_id_alloc(struct qxl_device *qdev,
 446                       struct qxl_bo *surf)
 447 {
 448         uint32_t handle;
 449         int idr_ret;
 450         int count = 0;
 451 again:
 452         idr_preload(GFP_ATOMIC);
 453         spin_lock(&qdev->surf_id_idr_lock);
 454         idr_ret = idr_alloc(&qdev->surf_id_idr, NULL, 1, 0, GFP_NOWAIT);
 455         spin_unlock(&qdev->surf_id_idr_lock);
 456         idr_preload_end();
 457         if (idr_ret < 0)
 458                 return idr_ret;
 459         handle = idr_ret;
 460
 461         if (handle >= qdev->rom->n_surfaces) {
 462                 count++;
 463                 spin_lock(&qdev->surf_id_idr_lock);
 464                 idr_remove(&qdev->surf_id_idr, handle);
 465                 spin_unlock(&qdev->surf_id_idr_lock);
 466                 qxl_reap_surface_id(qdev, 2);
 467                 goto again;
 468         }
 469         surf->surface_id = handle;
 470
 471         spin_lock(&qdev->surf_id_idr_lock);
 472         qdev->last_alloced_surf_id = handle;
 473         spin_unlock(&qdev->surf_id_idr_lock);
 474         return 0;
 475 }
 476
 477 void qxl_surface_id_dealloc(struct qxl_device *qdev,
 478                             uint32_t surface_id)
 479 {
 480         spin_lock(&qdev->surf_id_idr_lock);
 481         idr_remove(&qdev->surf_id_idr, surface_id);
 482         spin_unlock(&qdev->surf_id_idr_lock);
 483 }
 484
 485 int qxl_hw_surface_alloc(struct qxl_device *qdev,
 486                          struct qxl_bo *surf,
 487                          struct ttm_mem_reg *new_mem)
 488 {
 489         struct qxl_surface_cmd *cmd;
 490         struct qxl_release *release;
 491         int ret;
 492
 493         if (surf->hw_surf_alloc)
 494                 return 0;
 495
 496         ret = qxl_alloc_surface_release_reserved(qdev, QXL_SURFACE_CMD_CREATE,
 497                                                  NULL,
 498                                                  &release);
 499         if (ret)
 500                 return ret;
 501
 502         ret = qxl_release_reserve_list(release, true);
 503         if (ret)
 504                 return ret;
 505
 506         cmd = (struct qxl_surface_cmd *)qxl_release_map(qdev, release);
 507         cmd->type = QXL_SURFACE_CMD_CREATE;
 508         cmd->flags = QXL_SURF_FLAG_KEEP_DATA;
 509         cmd->u.surface_create.format = surf->surf.format;
 510         cmd->u.surface_create.width = surf->surf.width;
 511         cmd->u.surface_create.height = surf->surf.height;
 512         cmd->u.surface_create.stride = surf->surf.stride;
 513         if (new_mem) {
 514                 int slot_id = surf->type == QXL_GEM_DOMAIN_VRAM ? qdev->main_mem_slot : qdev->surfaces_mem_slot;
 515                 struct qxl_memslot *slot = &(qdev->mem_slots[slot_id]);
 516
 517                 /* TODO - need to hold one of the locks to read tbo.offset */
 518                 cmd->u.surface_create.data = slot->high_bits;
 519
 520                 cmd->u.surface_create.data |= (new_mem->start << PAGE_SHIFT) + surf->tbo.bdev->man[new_mem->mem_type].gpu_offset;
 521         } else
 522                 cmd->u.surface_create.data = qxl_bo_physical_address(qdev, surf, 0);
 523         cmd->surface_id = surf->surface_id;
 524         qxl_release_unmap(qdev, release, &cmd->release_info);
 525
 526         surf->surf_create = release;
 527
 528         /* no need to add a release to the fence for this surface bo,
 529            since it is only released when we ask to destroy the surface
 530            and it would never signal otherwise */
 531         qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false);
 532         qxl_release_fence_buffer_objects(release);
 533
 534         surf->hw_surf_alloc = true;
 535         spin_lock(&qdev->surf_id_idr_lock);
 536         idr_replace(&qdev->surf_id_idr, surf, surf->surface_id);
 537         spin_unlock(&qdev->surf_id_idr_lock);
 538         return 0;
 539 }
 540
 541 int qxl_hw_surface_dealloc(struct qxl_device *qdev,
 542                            struct qxl_bo *surf)
 543 {
 544         struct qxl_surface_cmd *cmd;
 545         struct qxl_release *release;
 546         int ret;
 547         int id;
 548
 549         if (!surf->hw_surf_alloc)
 550                 return 0;
 551
 552         ret = qxl_alloc_surface_release_reserved(qdev, QXL_SURFACE_CMD_DESTROY,
 553                                                  surf->surf_create,
 554                                                  &release);
 555         if (ret)
 556                 return ret;
 557
 558         surf->surf_create = NULL;
 559         /* remove the surface from the idr, but not the surface id yet */
 560         spin_lock(&qdev->surf_id_idr_lock);
 561         idr_replace(&qdev->surf_id_idr, NULL, surf->surface_id);
 562         spin_unlock(&qdev->surf_id_idr_lock);
 563         surf->hw_surf_alloc = false;
 564
 565         id = surf->surface_id;
 566         surf->surface_id = 0;
 567
 568         release->surface_release_id = id;
 569         cmd = (struct qxl_surface_cmd *)qxl_release_map(qdev, release);
 570         cmd->type = QXL_SURFACE_CMD_DESTROY;
 571         cmd->surface_id = id;
 572         qxl_release_unmap(qdev, release, &cmd->release_info);
 573
 574         qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false);
 575
 576         qxl_release_fence_buffer_objects(release);
 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 (stall)
 625                 mutex_unlock(&qdev->surf_evict_mutex);
 626
 627         ret = ttm_bo_wait(&surf->tbo, true, true, !stall);
 628
 629         if (stall)
 630                 mutex_lock(&qdev->surf_evict_mutex);
 631         if (ret == -EBUSY) {
 632                 qxl_bo_unreserve(surf);
 633                 return -EBUSY;
 634         }
 635
 636         qxl_surface_evict_locked(qdev, surf, true);
 637         qxl_bo_unreserve(surf);
 638         return 0;
 639 }
 640
 641 static int qxl_reap_surface_id(struct qxl_device *qdev, int max_to_reap)
 642 {
 643         int num_reaped = 0;
 644         int i, ret;
 645         bool stall = false;
 646         int start = 0;
 647
 648         mutex_lock(&qdev->surf_evict_mutex);
 649 again:
 650
 651         spin_lock(&qdev->surf_id_idr_lock);
 652         start = qdev->last_alloced_surf_id + 1;
 653         spin_unlock(&qdev->surf_id_idr_lock);
 654
 655         for (i = start; i < start + qdev->rom->n_surfaces; i++) {
 656                 void *objptr;
 657                 int surfid = i % qdev->rom->n_surfaces;
 658
 659                 /* this avoids the case where the objects is in the
 660                    idr but has been evicted half way - its makes
 661                    the idr lookup atomic with the eviction */
 662                 spin_lock(&qdev->surf_id_idr_lock);
 663                 objptr = idr_find(&qdev->surf_id_idr, surfid);
 664                 spin_unlock(&qdev->surf_id_idr_lock);
 665
 666                 if (!objptr)
 667                         continue;
 668
 669                 ret = qxl_reap_surf(qdev, objptr, stall);
 670                 if (ret == 0)
 671                         num_reaped++;
 672                 if (num_reaped >= max_to_reap)
 673                         break;
 674         }
 675         if (num_reaped == 0 && stall == false) {
 676                 stall = true;
 677                 goto again;
 678         }
 679
 680         mutex_unlock(&qdev->surf_evict_mutex);
 681         if (num_reaped) {
 682                 usleep_range(500, 1000);
 683                 qxl_queue_garbage_collect(qdev, true);
 684         }
 685
 686         return 0;
 687 }