qxl_cmd.c 16 KB

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  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. /* QXL cmd/ring handling */
  26. #include <linux/delay.h>
  27. #include <drm/drm_util.h>
  28. #include "qxl_drv.h"
  29. #include "qxl_object.h"
  30. static int qxl_reap_surface_id(struct qxl_device *qdev, int max_to_reap);
  31. struct ring {
  32. struct qxl_ring_header header;
  33. uint8_t elements[];
  34. };
  35. struct qxl_ring {
  36. struct ring *ring;
  37. int element_size;
  38. int n_elements;
  39. int prod_notify;
  40. wait_queue_head_t *push_event;
  41. spinlock_t lock;
  42. };
  43. void qxl_ring_free(struct qxl_ring *ring)
  44. {
  45. kfree(ring);
  46. }
  47. struct qxl_ring *
  48. qxl_ring_create(struct qxl_ring_header *header,
  49. int element_size,
  50. int n_elements,
  51. int prod_notify,
  52. wait_queue_head_t *push_event)
  53. {
  54. struct qxl_ring *ring;
  55. ring = kmalloc(sizeof(*ring), GFP_KERNEL);
  56. if (!ring)
  57. return NULL;
  58. ring->ring = (struct ring *)header;
  59. ring->element_size = element_size;
  60. ring->n_elements = n_elements;
  61. ring->prod_notify = prod_notify;
  62. ring->push_event = push_event;
  63. spin_lock_init(&ring->lock);
  64. return ring;
  65. }
  66. static int qxl_check_header(struct qxl_ring *ring)
  67. {
  68. int ret;
  69. struct qxl_ring_header *header = &(ring->ring->header);
  70. unsigned long flags;
  71. spin_lock_irqsave(&ring->lock, flags);
  72. ret = header->prod - header->cons < header->num_items;
  73. if (ret == 0)
  74. header->notify_on_cons = header->cons + 1;
  75. spin_unlock_irqrestore(&ring->lock, flags);
  76. return ret;
  77. }
  78. int qxl_check_idle(struct qxl_ring *ring)
  79. {
  80. int ret;
  81. struct qxl_ring_header *header = &(ring->ring->header);
  82. unsigned long flags;
  83. spin_lock_irqsave(&ring->lock, flags);
  84. ret = header->prod == header->cons;
  85. spin_unlock_irqrestore(&ring->lock, flags);
  86. return ret;
  87. }
  88. int qxl_ring_push(struct qxl_ring *ring,
  89. const void *new_elt, bool interruptible)
  90. {
  91. struct qxl_ring_header *header = &(ring->ring->header);
  92. uint8_t *elt;
  93. int idx, ret;
  94. unsigned long flags;
  95. spin_lock_irqsave(&ring->lock, flags);
  96. if (header->prod - header->cons == header->num_items) {
  97. header->notify_on_cons = header->cons + 1;
  98. mb();
  99. spin_unlock_irqrestore(&ring->lock, flags);
  100. if (!drm_can_sleep()) {
  101. while (!qxl_check_header(ring))
  102. udelay(1);
  103. } else {
  104. if (interruptible) {
  105. ret = wait_event_interruptible(*ring->push_event,
  106. qxl_check_header(ring));
  107. if (ret)
  108. return ret;
  109. } else {
  110. wait_event(*ring->push_event,
  111. qxl_check_header(ring));
  112. }
  113. }
  114. spin_lock_irqsave(&ring->lock, flags);
  115. }
  116. idx = header->prod & (ring->n_elements - 1);
  117. elt = ring->ring->elements + idx * ring->element_size;
  118. memcpy((void *)elt, new_elt, ring->element_size);
  119. header->prod++;
  120. mb();
  121. if (header->prod == header->notify_on_prod)
  122. outb(0, ring->prod_notify);
  123. spin_unlock_irqrestore(&ring->lock, flags);
  124. return 0;
  125. }
  126. static bool qxl_ring_pop(struct qxl_ring *ring,
  127. void *element)
  128. {
  129. volatile struct qxl_ring_header *header = &(ring->ring->header);
  130. volatile uint8_t *ring_elt;
  131. int idx;
  132. unsigned long flags;
  133. spin_lock_irqsave(&ring->lock, flags);
  134. if (header->cons == header->prod) {
  135. header->notify_on_prod = header->cons + 1;
  136. spin_unlock_irqrestore(&ring->lock, flags);
  137. return false;
  138. }
  139. idx = header->cons & (ring->n_elements - 1);
  140. ring_elt = ring->ring->elements + idx * ring->element_size;
  141. memcpy(element, (void *)ring_elt, ring->element_size);
  142. header->cons++;
  143. spin_unlock_irqrestore(&ring->lock, flags);
  144. return true;
  145. }
  146. int
  147. qxl_push_command_ring_release(struct qxl_device *qdev, struct qxl_release *release,
  148. uint32_t type, bool interruptible)
  149. {
  150. struct qxl_command cmd;
  151. cmd.type = type;
  152. cmd.data = qxl_bo_physical_address(qdev, release->release_bo, release->release_offset);
  153. return qxl_ring_push(qdev->command_ring, &cmd, interruptible);
  154. }
  155. int
  156. qxl_push_cursor_ring_release(struct qxl_device *qdev, struct qxl_release *release,
  157. uint32_t type, bool interruptible)
  158. {
  159. struct qxl_command cmd;
  160. cmd.type = type;
  161. cmd.data = qxl_bo_physical_address(qdev, release->release_bo, release->release_offset);
  162. return qxl_ring_push(qdev->cursor_ring, &cmd, interruptible);
  163. }
  164. bool qxl_queue_garbage_collect(struct qxl_device *qdev, bool flush)
  165. {
  166. if (!qxl_check_idle(qdev->release_ring)) {
  167. schedule_work(&qdev->gc_work);
  168. if (flush)
  169. flush_work(&qdev->gc_work);
  170. return true;
  171. }
  172. return false;
  173. }
  174. int qxl_garbage_collect(struct qxl_device *qdev)
  175. {
  176. struct qxl_release *release;
  177. uint64_t id, next_id;
  178. int i = 0;
  179. union qxl_release_info *info;
  180. while (qxl_ring_pop(qdev->release_ring, &id)) {
  181. DRM_DEBUG_DRIVER("popped %lld\n", id);
  182. while (id) {
  183. release = qxl_release_from_id_locked(qdev, id);
  184. if (release == NULL)
  185. break;
  186. info = qxl_release_map(qdev, release);
  187. next_id = info->next;
  188. qxl_release_unmap(qdev, release, info);
  189. DRM_DEBUG_DRIVER("popped %lld, next %lld\n", id,
  190. next_id);
  191. switch (release->type) {
  192. case QXL_RELEASE_DRAWABLE:
  193. case QXL_RELEASE_SURFACE_CMD:
  194. case QXL_RELEASE_CURSOR_CMD:
  195. break;
  196. default:
  197. DRM_ERROR("unexpected release type\n");
  198. break;
  199. }
  200. id = next_id;
  201. qxl_release_free(qdev, release);
  202. ++i;
  203. }
  204. }
  205. wake_up_all(&qdev->release_event);
  206. DRM_DEBUG_DRIVER("%d\n", i);
  207. return i;
  208. }
  209. int qxl_alloc_bo_reserved(struct qxl_device *qdev,
  210. struct qxl_release *release,
  211. unsigned long size,
  212. struct qxl_bo **_bo)
  213. {
  214. struct qxl_bo *bo;
  215. int ret;
  216. ret = qxl_bo_create(qdev, size, false /* not kernel - device */,
  217. false, QXL_GEM_DOMAIN_VRAM, 0, NULL, &bo);
  218. if (ret) {
  219. DRM_ERROR("failed to allocate VRAM BO\n");
  220. return ret;
  221. }
  222. ret = qxl_release_list_add(release, bo);
  223. if (ret)
  224. goto out_unref;
  225. *_bo = bo;
  226. return 0;
  227. out_unref:
  228. qxl_bo_unref(&bo);
  229. return ret;
  230. }
  231. static int wait_for_io_cmd_user(struct qxl_device *qdev, uint8_t val, long port, bool intr)
  232. {
  233. int irq_num;
  234. long addr = qdev->io_base + port;
  235. int ret;
  236. mutex_lock(&qdev->async_io_mutex);
  237. irq_num = atomic_read(&qdev->irq_received_io_cmd);
  238. if (qdev->last_sent_io_cmd > irq_num) {
  239. if (intr)
  240. ret = wait_event_interruptible_timeout(qdev->io_cmd_event,
  241. atomic_read(&qdev->irq_received_io_cmd) > irq_num, 5*HZ);
  242. else
  243. ret = wait_event_timeout(qdev->io_cmd_event,
  244. atomic_read(&qdev->irq_received_io_cmd) > irq_num, 5*HZ);
  245. /* 0 is timeout, just bail the "hw" has gone away */
  246. if (ret <= 0)
  247. goto out;
  248. irq_num = atomic_read(&qdev->irq_received_io_cmd);
  249. }
  250. outb(val, addr);
  251. qdev->last_sent_io_cmd = irq_num + 1;
  252. if (intr)
  253. ret = wait_event_interruptible_timeout(qdev->io_cmd_event,
  254. atomic_read(&qdev->irq_received_io_cmd) > irq_num, 5*HZ);
  255. else
  256. ret = wait_event_timeout(qdev->io_cmd_event,
  257. atomic_read(&qdev->irq_received_io_cmd) > irq_num, 5*HZ);
  258. out:
  259. if (ret > 0)
  260. ret = 0;
  261. mutex_unlock(&qdev->async_io_mutex);
  262. return ret;
  263. }
  264. static void wait_for_io_cmd(struct qxl_device *qdev, uint8_t val, long port)
  265. {
  266. int ret;
  267. restart:
  268. ret = wait_for_io_cmd_user(qdev, val, port, false);
  269. if (ret == -ERESTARTSYS)
  270. goto restart;
  271. }
  272. int qxl_io_update_area(struct qxl_device *qdev, struct qxl_bo *surf,
  273. const struct qxl_rect *area)
  274. {
  275. int surface_id;
  276. uint32_t surface_width, surface_height;
  277. int ret;
  278. if (!surf->hw_surf_alloc)
  279. DRM_ERROR("got io update area with no hw surface\n");
  280. if (surf->is_primary)
  281. surface_id = 0;
  282. else
  283. surface_id = surf->surface_id;
  284. surface_width = surf->surf.width;
  285. surface_height = surf->surf.height;
  286. if (area->left < 0 || area->top < 0 ||
  287. area->right > surface_width || area->bottom > surface_height)
  288. return -EINVAL;
  289. mutex_lock(&qdev->update_area_mutex);
  290. qdev->ram_header->update_area = *area;
  291. qdev->ram_header->update_surface = surface_id;
  292. ret = wait_for_io_cmd_user(qdev, 0, QXL_IO_UPDATE_AREA_ASYNC, true);
  293. mutex_unlock(&qdev->update_area_mutex);
  294. return ret;
  295. }
  296. void qxl_io_notify_oom(struct qxl_device *qdev)
  297. {
  298. outb(0, qdev->io_base + QXL_IO_NOTIFY_OOM);
  299. }
  300. void qxl_io_flush_release(struct qxl_device *qdev)
  301. {
  302. outb(0, qdev->io_base + QXL_IO_FLUSH_RELEASE);
  303. }
  304. void qxl_io_flush_surfaces(struct qxl_device *qdev)
  305. {
  306. wait_for_io_cmd(qdev, 0, QXL_IO_FLUSH_SURFACES_ASYNC);
  307. }
  308. void qxl_io_destroy_primary(struct qxl_device *qdev)
  309. {
  310. wait_for_io_cmd(qdev, 0, QXL_IO_DESTROY_PRIMARY_ASYNC);
  311. qdev->primary_bo->is_primary = false;
  312. drm_gem_object_put(&qdev->primary_bo->tbo.base);
  313. qdev->primary_bo = NULL;
  314. }
  315. void qxl_io_create_primary(struct qxl_device *qdev, struct qxl_bo *bo)
  316. {
  317. struct qxl_surface_create *create;
  318. if (WARN_ON(qdev->primary_bo))
  319. return;
  320. DRM_DEBUG_DRIVER("qdev %p, ram_header %p\n", qdev, qdev->ram_header);
  321. create = &qdev->ram_header->create_surface;
  322. create->format = bo->surf.format;
  323. create->width = bo->surf.width;
  324. create->height = bo->surf.height;
  325. create->stride = bo->surf.stride;
  326. create->mem = qxl_bo_physical_address(qdev, bo, 0);
  327. DRM_DEBUG_DRIVER("mem = %llx, from %p\n", create->mem, bo->kptr);
  328. create->flags = QXL_SURF_FLAG_KEEP_DATA;
  329. create->type = QXL_SURF_TYPE_PRIMARY;
  330. wait_for_io_cmd(qdev, 0, QXL_IO_CREATE_PRIMARY_ASYNC);
  331. qdev->primary_bo = bo;
  332. qdev->primary_bo->is_primary = true;
  333. drm_gem_object_get(&qdev->primary_bo->tbo.base);
  334. }
  335. void qxl_io_memslot_add(struct qxl_device *qdev, uint8_t id)
  336. {
  337. DRM_DEBUG_DRIVER("qxl_memslot_add %d\n", id);
  338. wait_for_io_cmd(qdev, id, QXL_IO_MEMSLOT_ADD_ASYNC);
  339. }
  340. void qxl_io_reset(struct qxl_device *qdev)
  341. {
  342. outb(0, qdev->io_base + QXL_IO_RESET);
  343. }
  344. void qxl_io_monitors_config(struct qxl_device *qdev)
  345. {
  346. wait_for_io_cmd(qdev, 0, QXL_IO_MONITORS_CONFIG_ASYNC);
  347. }
  348. int qxl_surface_id_alloc(struct qxl_device *qdev,
  349. struct qxl_bo *surf)
  350. {
  351. uint32_t handle;
  352. int idr_ret;
  353. int count = 0;
  354. again:
  355. idr_preload(GFP_ATOMIC);
  356. spin_lock(&qdev->surf_id_idr_lock);
  357. idr_ret = idr_alloc(&qdev->surf_id_idr, NULL, 1, 0, GFP_NOWAIT);
  358. spin_unlock(&qdev->surf_id_idr_lock);
  359. idr_preload_end();
  360. if (idr_ret < 0)
  361. return idr_ret;
  362. handle = idr_ret;
  363. if (handle >= qdev->rom->n_surfaces) {
  364. count++;
  365. spin_lock(&qdev->surf_id_idr_lock);
  366. idr_remove(&qdev->surf_id_idr, handle);
  367. spin_unlock(&qdev->surf_id_idr_lock);
  368. qxl_reap_surface_id(qdev, 2);
  369. goto again;
  370. }
  371. surf->surface_id = handle;
  372. spin_lock(&qdev->surf_id_idr_lock);
  373. qdev->last_alloced_surf_id = handle;
  374. spin_unlock(&qdev->surf_id_idr_lock);
  375. return 0;
  376. }
  377. void qxl_surface_id_dealloc(struct qxl_device *qdev,
  378. uint32_t surface_id)
  379. {
  380. spin_lock(&qdev->surf_id_idr_lock);
  381. idr_remove(&qdev->surf_id_idr, surface_id);
  382. spin_unlock(&qdev->surf_id_idr_lock);
  383. }
  384. int qxl_hw_surface_alloc(struct qxl_device *qdev,
  385. struct qxl_bo *surf)
  386. {
  387. struct qxl_surface_cmd *cmd;
  388. struct qxl_release *release;
  389. int ret;
  390. if (surf->hw_surf_alloc)
  391. return 0;
  392. ret = qxl_alloc_surface_release_reserved(qdev, QXL_SURFACE_CMD_CREATE,
  393. NULL,
  394. &release);
  395. if (ret)
  396. return ret;
  397. ret = qxl_release_reserve_list(release, true);
  398. if (ret) {
  399. qxl_release_free(qdev, release);
  400. return ret;
  401. }
  402. cmd = (struct qxl_surface_cmd *)qxl_release_map(qdev, release);
  403. cmd->type = QXL_SURFACE_CMD_CREATE;
  404. cmd->flags = QXL_SURF_FLAG_KEEP_DATA;
  405. cmd->u.surface_create.format = surf->surf.format;
  406. cmd->u.surface_create.width = surf->surf.width;
  407. cmd->u.surface_create.height = surf->surf.height;
  408. cmd->u.surface_create.stride = surf->surf.stride;
  409. cmd->u.surface_create.data = qxl_bo_physical_address(qdev, surf, 0);
  410. cmd->surface_id = surf->surface_id;
  411. qxl_release_unmap(qdev, release, &cmd->release_info);
  412. surf->surf_create = release;
  413. /* no need to add a release to the fence for this surface bo,
  414. since it is only released when we ask to destroy the surface
  415. and it would never signal otherwise */
  416. qxl_release_fence_buffer_objects(release);
  417. qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false);
  418. surf->hw_surf_alloc = true;
  419. spin_lock(&qdev->surf_id_idr_lock);
  420. idr_replace(&qdev->surf_id_idr, surf, surf->surface_id);
  421. spin_unlock(&qdev->surf_id_idr_lock);
  422. return 0;
  423. }
  424. int qxl_hw_surface_dealloc(struct qxl_device *qdev,
  425. struct qxl_bo *surf)
  426. {
  427. struct qxl_surface_cmd *cmd;
  428. struct qxl_release *release;
  429. int ret;
  430. int id;
  431. if (!surf->hw_surf_alloc)
  432. return 0;
  433. ret = qxl_alloc_surface_release_reserved(qdev, QXL_SURFACE_CMD_DESTROY,
  434. surf->surf_create,
  435. &release);
  436. if (ret)
  437. return ret;
  438. surf->surf_create = NULL;
  439. /* remove the surface from the idr, but not the surface id yet */
  440. spin_lock(&qdev->surf_id_idr_lock);
  441. idr_replace(&qdev->surf_id_idr, NULL, surf->surface_id);
  442. spin_unlock(&qdev->surf_id_idr_lock);
  443. surf->hw_surf_alloc = false;
  444. id = surf->surface_id;
  445. surf->surface_id = 0;
  446. release->surface_release_id = id;
  447. cmd = (struct qxl_surface_cmd *)qxl_release_map(qdev, release);
  448. cmd->type = QXL_SURFACE_CMD_DESTROY;
  449. cmd->surface_id = id;
  450. qxl_release_unmap(qdev, release, &cmd->release_info);
  451. qxl_release_fence_buffer_objects(release);
  452. qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false);
  453. return 0;
  454. }
  455. static int qxl_update_surface(struct qxl_device *qdev, struct qxl_bo *surf)
  456. {
  457. struct qxl_rect rect;
  458. int ret;
  459. /* if we are evicting, we need to make sure the surface is up
  460. to date */
  461. rect.left = 0;
  462. rect.right = surf->surf.width;
  463. rect.top = 0;
  464. rect.bottom = surf->surf.height;
  465. retry:
  466. ret = qxl_io_update_area(qdev, surf, &rect);
  467. if (ret == -ERESTARTSYS)
  468. goto retry;
  469. return ret;
  470. }
  471. static void qxl_surface_evict_locked(struct qxl_device *qdev, struct qxl_bo *surf, bool do_update_area)
  472. {
  473. /* no need to update area if we are just freeing the surface normally */
  474. if (do_update_area)
  475. qxl_update_surface(qdev, surf);
  476. /* nuke the surface id at the hw */
  477. qxl_hw_surface_dealloc(qdev, surf);
  478. }
  479. void qxl_surface_evict(struct qxl_device *qdev, struct qxl_bo *surf, bool do_update_area)
  480. {
  481. mutex_lock(&qdev->surf_evict_mutex);
  482. qxl_surface_evict_locked(qdev, surf, do_update_area);
  483. mutex_unlock(&qdev->surf_evict_mutex);
  484. }
  485. static int qxl_reap_surf(struct qxl_device *qdev, struct qxl_bo *surf, bool stall)
  486. {
  487. int ret;
  488. ret = qxl_bo_reserve(surf);
  489. if (ret)
  490. return ret;
  491. if (stall)
  492. mutex_unlock(&qdev->surf_evict_mutex);
  493. ret = ttm_bo_wait(&surf->tbo, true, !stall);
  494. if (stall)
  495. mutex_lock(&qdev->surf_evict_mutex);
  496. if (ret) {
  497. qxl_bo_unreserve(surf);
  498. return ret;
  499. }
  500. qxl_surface_evict_locked(qdev, surf, true);
  501. qxl_bo_unreserve(surf);
  502. return 0;
  503. }
  504. static int qxl_reap_surface_id(struct qxl_device *qdev, int max_to_reap)
  505. {
  506. int num_reaped = 0;
  507. int i, ret;
  508. bool stall = false;
  509. int start = 0;
  510. mutex_lock(&qdev->surf_evict_mutex);
  511. again:
  512. spin_lock(&qdev->surf_id_idr_lock);
  513. start = qdev->last_alloced_surf_id + 1;
  514. spin_unlock(&qdev->surf_id_idr_lock);
  515. for (i = start; i < start + qdev->rom->n_surfaces; i++) {
  516. void *objptr;
  517. int surfid = i % qdev->rom->n_surfaces;
  518. /* this avoids the case where the objects is in the
  519. idr but has been evicted half way - its makes
  520. the idr lookup atomic with the eviction */
  521. spin_lock(&qdev->surf_id_idr_lock);
  522. objptr = idr_find(&qdev->surf_id_idr, surfid);
  523. spin_unlock(&qdev->surf_id_idr_lock);
  524. if (!objptr)
  525. continue;
  526. ret = qxl_reap_surf(qdev, objptr, stall);
  527. if (ret == 0)
  528. num_reaped++;
  529. if (num_reaped >= max_to_reap)
  530. break;
  531. }
  532. if (num_reaped == 0 && stall == false) {
  533. stall = true;
  534. goto again;
  535. }
  536. mutex_unlock(&qdev->surf_evict_mutex);
  537. if (num_reaped) {
  538. usleep_range(500, 1000);
  539. qxl_queue_garbage_collect(qdev, true);
  540. }
  541. return 0;
  542. }