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 <linux/delay.h>
29 
30 #include <drm/drm_util.h>
31 
32 #include "qxl_drv.h"
33 #include "qxl_object.h"
34 
35 static int qxl_reap_surface_id(struct qxl_device *qdev, int max_to_reap);
36 
37 struct ring {
38 	struct qxl_ring_header      header;
39 	uint8_t                     elements[];
40 };
41 
42 struct qxl_ring {
43 	struct ring	       *ring;
44 	int			element_size;
45 	int			n_elements;
46 	int			prod_notify;
47 	wait_queue_head_t      *push_event;
48 	spinlock_t             lock;
49 };
50 
qxl_ring_free(struct qxl_ring * ring)51 void qxl_ring_free(struct qxl_ring *ring)
52 {
53 	kfree(ring);
54 }
55 
56 struct qxl_ring *
qxl_ring_create(struct qxl_ring_header * header,int element_size,int n_elements,int prod_notify,wait_queue_head_t * push_event)57 qxl_ring_create(struct qxl_ring_header *header,
58 		int element_size,
59 		int n_elements,
60 		int prod_notify,
61 		wait_queue_head_t *push_event)
62 {
63 	struct qxl_ring *ring;
64 
65 	ring = kmalloc(sizeof(*ring), GFP_KERNEL);
66 	if (!ring)
67 		return NULL;
68 
69 	ring->ring = (struct ring *)header;
70 	ring->element_size = element_size;
71 	ring->n_elements = n_elements;
72 	ring->prod_notify = prod_notify;
73 	ring->push_event = push_event;
74 	spin_lock_init(&ring->lock);
75 	return ring;
76 }
77 
qxl_check_header(struct qxl_ring * ring)78 static int qxl_check_header(struct qxl_ring *ring)
79 {
80 	int ret;
81 	struct qxl_ring_header *header = &(ring->ring->header);
82 	unsigned long flags;
83 
84 	spin_lock_irqsave(&ring->lock, flags);
85 	ret = header->prod - header->cons < header->num_items;
86 	if (ret == 0)
87 		header->notify_on_cons = header->cons + 1;
88 	spin_unlock_irqrestore(&ring->lock, flags);
89 	return ret;
90 }
91 
qxl_check_idle(struct qxl_ring * ring)92 int qxl_check_idle(struct qxl_ring *ring)
93 {
94 	int ret;
95 	struct qxl_ring_header *header = &(ring->ring->header);
96 	unsigned long flags;
97 
98 	spin_lock_irqsave(&ring->lock, flags);
99 	ret = header->prod == header->cons;
100 	spin_unlock_irqrestore(&ring->lock, flags);
101 	return ret;
102 }
103 
qxl_ring_push(struct qxl_ring * ring,const void * new_elt,bool interruptible)104 int qxl_ring_push(struct qxl_ring *ring,
105 		  const void *new_elt, bool interruptible)
106 {
107 	struct qxl_ring_header *header = &(ring->ring->header);
108 	uint8_t *elt;
109 	int idx, ret;
110 	unsigned long flags;
111 
112 	spin_lock_irqsave(&ring->lock, flags);
113 	if (header->prod - header->cons == header->num_items) {
114 		header->notify_on_cons = header->cons + 1;
115 		mb();
116 		spin_unlock_irqrestore(&ring->lock, flags);
117 		if (!drm_can_sleep()) {
118 			while (!qxl_check_header(ring))
119 				udelay(1);
120 		} else {
121 			if (interruptible) {
122 				ret = wait_event_interruptible(*ring->push_event,
123 							       qxl_check_header(ring));
124 				if (ret)
125 					return ret;
126 			} else {
127 				wait_event(*ring->push_event,
128 					   qxl_check_header(ring));
129 			}
130 
131 		}
132 		spin_lock_irqsave(&ring->lock, flags);
133 	}
134 
135 	idx = header->prod & (ring->n_elements - 1);
136 	elt = ring->ring->elements + idx * ring->element_size;
137 
138 	memcpy((void *)elt, new_elt, ring->element_size);
139 
140 	header->prod++;
141 
142 	mb();
143 
144 	if (header->prod == header->notify_on_prod)
145 		outb(0, ring->prod_notify);
146 
147 	spin_unlock_irqrestore(&ring->lock, flags);
148 	return 0;
149 }
150 
qxl_ring_pop(struct qxl_ring * ring,void * element)151 static bool qxl_ring_pop(struct qxl_ring *ring,
152 			 void *element)
153 {
154 	volatile struct qxl_ring_header *header = &(ring->ring->header);
155 	volatile uint8_t *ring_elt;
156 	int idx;
157 	unsigned long flags;
158 
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
qxl_push_command_ring_release(struct qxl_device * qdev,struct qxl_release * release,uint32_t type,bool interruptible)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 
183 	cmd.type = type;
184 	cmd.data = qxl_bo_physical_address(qdev, release->release_bo, release->release_offset);
185 
186 	return qxl_ring_push(qdev->command_ring, &cmd, interruptible);
187 }
188 
189 int
qxl_push_cursor_ring_release(struct qxl_device * qdev,struct qxl_release * release,uint32_t type,bool interruptible)190 qxl_push_cursor_ring_release(struct qxl_device *qdev, struct qxl_release *release,
191 			     uint32_t type, bool interruptible)
192 {
193 	struct qxl_command cmd;
194 
195 	cmd.type = type;
196 	cmd.data = qxl_bo_physical_address(qdev, release->release_bo, release->release_offset);
197 
198 	return qxl_ring_push(qdev->cursor_ring, &cmd, interruptible);
199 }
200 
qxl_queue_garbage_collect(struct qxl_device * qdev,bool flush)201 bool qxl_queue_garbage_collect(struct qxl_device *qdev, bool flush)
202 {
203 	if (!qxl_check_idle(qdev->release_ring)) {
204 		schedule_work(&qdev->gc_work);
205 		if (flush)
206 			flush_work(&qdev->gc_work);
207 		return true;
208 	}
209 	return false;
210 }
211 
qxl_garbage_collect(struct qxl_device * qdev)212 int qxl_garbage_collect(struct qxl_device *qdev)
213 {
214 	struct qxl_release *release;
215 	uint64_t id, next_id;
216 	int i = 0;
217 	union qxl_release_info *info;
218 
219 	while (qxl_ring_pop(qdev->release_ring, &id)) {
220 		DRM_DEBUG_DRIVER("popped %lld\n", id);
221 		while (id) {
222 			release = qxl_release_from_id_locked(qdev, id);
223 			if (release == NULL)
224 				break;
225 
226 			info = qxl_release_map(qdev, release);
227 			next_id = info->next;
228 			qxl_release_unmap(qdev, release, info);
229 
230 			DRM_DEBUG_DRIVER("popped %lld, next %lld\n", id,
231 					 next_id);
232 
233 			switch (release->type) {
234 			case QXL_RELEASE_DRAWABLE:
235 			case QXL_RELEASE_SURFACE_CMD:
236 			case QXL_RELEASE_CURSOR_CMD:
237 				break;
238 			default:
239 				DRM_ERROR("unexpected release type\n");
240 				break;
241 			}
242 			id = next_id;
243 
244 			qxl_release_free(qdev, release);
245 			++i;
246 		}
247 	}
248 
249 	wake_up_all(&qdev->release_event);
250 	DRM_DEBUG_DRIVER("%d\n", i);
251 
252 	return i;
253 }
254 
qxl_alloc_bo_reserved(struct qxl_device * qdev,struct qxl_release * release,unsigned long size,struct qxl_bo ** _bo)255 int qxl_alloc_bo_reserved(struct qxl_device *qdev,
256 			  struct qxl_release *release,
257 			  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 			    false, QXL_GEM_DOMAIN_VRAM, 0, NULL, &bo);
265 	if (ret) {
266 		DRM_ERROR("failed to allocate VRAM BO\n");
267 		return ret;
268 	}
269 	ret = qxl_release_list_add(release, bo);
270 	if (ret)
271 		goto out_unref;
272 
273 	*_bo = bo;
274 	return 0;
275 out_unref:
276 	qxl_bo_unref(&bo);
277 	return ret;
278 }
279 
wait_for_io_cmd_user(struct qxl_device * qdev,uint8_t val,long port,bool intr)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 
wait_for_io_cmd(struct qxl_device * qdev,uint8_t val,long port)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 
qxl_io_update_area(struct qxl_device * qdev,struct qxl_bo * surf,const struct qxl_rect * area)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 		return -EINVAL;
345 
346 	mutex_lock(&qdev->update_area_mutex);
347 	qdev->ram_header->update_area = *area;
348 	qdev->ram_header->update_surface = surface_id;
349 	ret = wait_for_io_cmd_user(qdev, 0, QXL_IO_UPDATE_AREA_ASYNC, true);
350 	mutex_unlock(&qdev->update_area_mutex);
351 	return ret;
352 }
353 
qxl_io_notify_oom(struct qxl_device * qdev)354 void qxl_io_notify_oom(struct qxl_device *qdev)
355 {
356 	outb(0, qdev->io_base + QXL_IO_NOTIFY_OOM);
357 }
358 
qxl_io_flush_release(struct qxl_device * qdev)359 void qxl_io_flush_release(struct qxl_device *qdev)
360 {
361 	outb(0, qdev->io_base + QXL_IO_FLUSH_RELEASE);
362 }
363 
qxl_io_flush_surfaces(struct qxl_device * qdev)364 void qxl_io_flush_surfaces(struct qxl_device *qdev)
365 {
366 	wait_for_io_cmd(qdev, 0, QXL_IO_FLUSH_SURFACES_ASYNC);
367 }
368 
qxl_io_destroy_primary(struct qxl_device * qdev)369 void qxl_io_destroy_primary(struct qxl_device *qdev)
370 {
371 	wait_for_io_cmd(qdev, 0, QXL_IO_DESTROY_PRIMARY_ASYNC);
372 	qdev->primary_bo->is_primary = false;
373 	drm_gem_object_put(&qdev->primary_bo->tbo.base);
374 	qdev->primary_bo = NULL;
375 }
376 
qxl_io_create_primary(struct qxl_device * qdev,struct qxl_bo * bo)377 void qxl_io_create_primary(struct qxl_device *qdev, struct qxl_bo *bo)
378 {
379 	struct qxl_surface_create *create;
380 
381 	if (WARN_ON(qdev->primary_bo))
382 		return;
383 
384 	DRM_DEBUG_DRIVER("qdev %p, ram_header %p\n", qdev, qdev->ram_header);
385 	create = &qdev->ram_header->create_surface;
386 	create->format = bo->surf.format;
387 	create->width = bo->surf.width;
388 	create->height = bo->surf.height;
389 	create->stride = bo->surf.stride;
390 	create->mem = qxl_bo_physical_address(qdev, bo, 0);
391 
392 	DRM_DEBUG_DRIVER("mem = %llx, from %p\n", create->mem, bo->kptr);
393 
394 	create->flags = QXL_SURF_FLAG_KEEP_DATA;
395 	create->type = QXL_SURF_TYPE_PRIMARY;
396 
397 	wait_for_io_cmd(qdev, 0, QXL_IO_CREATE_PRIMARY_ASYNC);
398 	qdev->primary_bo = bo;
399 	qdev->primary_bo->is_primary = true;
400 	drm_gem_object_get(&qdev->primary_bo->tbo.base);
401 }
402 
qxl_io_memslot_add(struct qxl_device * qdev,uint8_t id)403 void qxl_io_memslot_add(struct qxl_device *qdev, uint8_t id)
404 {
405 	DRM_DEBUG_DRIVER("qxl_memslot_add %d\n", id);
406 	wait_for_io_cmd(qdev, id, QXL_IO_MEMSLOT_ADD_ASYNC);
407 }
408 
qxl_io_reset(struct qxl_device * qdev)409 void qxl_io_reset(struct qxl_device *qdev)
410 {
411 	outb(0, qdev->io_base + QXL_IO_RESET);
412 }
413 
qxl_io_monitors_config(struct qxl_device * qdev)414 void qxl_io_monitors_config(struct qxl_device *qdev)
415 {
416 	wait_for_io_cmd(qdev, 0, QXL_IO_MONITORS_CONFIG_ASYNC);
417 }
418 
qxl_surface_id_alloc(struct qxl_device * qdev,struct qxl_bo * surf)419 int qxl_surface_id_alloc(struct qxl_device *qdev,
420 		      struct qxl_bo *surf)
421 {
422 	uint32_t handle;
423 	int idr_ret;
424 	int count = 0;
425 again:
426 	idr_preload(GFP_ATOMIC);
427 	spin_lock(&qdev->surf_id_idr_lock);
428 	idr_ret = idr_alloc(&qdev->surf_id_idr, NULL, 1, 0, GFP_NOWAIT);
429 	spin_unlock(&qdev->surf_id_idr_lock);
430 	idr_preload_end();
431 	if (idr_ret < 0)
432 		return idr_ret;
433 	handle = idr_ret;
434 
435 	if (handle >= qdev->rom->n_surfaces) {
436 		count++;
437 		spin_lock(&qdev->surf_id_idr_lock);
438 		idr_remove(&qdev->surf_id_idr, handle);
439 		spin_unlock(&qdev->surf_id_idr_lock);
440 		qxl_reap_surface_id(qdev, 2);
441 		goto again;
442 	}
443 	surf->surface_id = handle;
444 
445 	spin_lock(&qdev->surf_id_idr_lock);
446 	qdev->last_alloced_surf_id = handle;
447 	spin_unlock(&qdev->surf_id_idr_lock);
448 	return 0;
449 }
450 
qxl_surface_id_dealloc(struct qxl_device * qdev,uint32_t surface_id)451 void qxl_surface_id_dealloc(struct qxl_device *qdev,
452 			    uint32_t surface_id)
453 {
454 	spin_lock(&qdev->surf_id_idr_lock);
455 	idr_remove(&qdev->surf_id_idr, surface_id);
456 	spin_unlock(&qdev->surf_id_idr_lock);
457 }
458 
qxl_hw_surface_alloc(struct qxl_device * qdev,struct qxl_bo * surf)459 int qxl_hw_surface_alloc(struct qxl_device *qdev,
460 			 struct qxl_bo *surf)
461 {
462 	struct qxl_surface_cmd *cmd;
463 	struct qxl_release *release;
464 	int ret;
465 
466 	if (surf->hw_surf_alloc)
467 		return 0;
468 
469 	ret = qxl_alloc_surface_release_reserved(qdev, QXL_SURFACE_CMD_CREATE,
470 						 NULL,
471 						 &release);
472 	if (ret)
473 		return ret;
474 
475 	ret = qxl_release_reserve_list(release, true);
476 	if (ret) {
477 		qxl_release_free(qdev, release);
478 		return ret;
479 	}
480 	cmd = (struct qxl_surface_cmd *)qxl_release_map(qdev, release);
481 	cmd->type = QXL_SURFACE_CMD_CREATE;
482 	cmd->flags = QXL_SURF_FLAG_KEEP_DATA;
483 	cmd->u.surface_create.format = surf->surf.format;
484 	cmd->u.surface_create.width = surf->surf.width;
485 	cmd->u.surface_create.height = surf->surf.height;
486 	cmd->u.surface_create.stride = surf->surf.stride;
487 	cmd->u.surface_create.data = qxl_bo_physical_address(qdev, surf, 0);
488 	cmd->surface_id = surf->surface_id;
489 	qxl_release_unmap(qdev, release, &cmd->release_info);
490 
491 	surf->surf_create = release;
492 
493 	/* no need to add a release to the fence for this surface bo,
494 	   since it is only released when we ask to destroy the surface
495 	   and it would never signal otherwise */
496 	qxl_release_fence_buffer_objects(release);
497 	qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false);
498 
499 	surf->hw_surf_alloc = true;
500 	spin_lock(&qdev->surf_id_idr_lock);
501 	idr_replace(&qdev->surf_id_idr, surf, surf->surface_id);
502 	spin_unlock(&qdev->surf_id_idr_lock);
503 	return 0;
504 }
505 
qxl_hw_surface_dealloc(struct qxl_device * qdev,struct qxl_bo * surf)506 int qxl_hw_surface_dealloc(struct qxl_device *qdev,
507 			   struct qxl_bo *surf)
508 {
509 	struct qxl_surface_cmd *cmd;
510 	struct qxl_release *release;
511 	int ret;
512 	int id;
513 
514 	if (!surf->hw_surf_alloc)
515 		return 0;
516 
517 	ret = qxl_alloc_surface_release_reserved(qdev, QXL_SURFACE_CMD_DESTROY,
518 						 surf->surf_create,
519 						 &release);
520 	if (ret)
521 		return ret;
522 
523 	surf->surf_create = NULL;
524 	/* remove the surface from the idr, but not the surface id yet */
525 	spin_lock(&qdev->surf_id_idr_lock);
526 	idr_replace(&qdev->surf_id_idr, NULL, surf->surface_id);
527 	spin_unlock(&qdev->surf_id_idr_lock);
528 	surf->hw_surf_alloc = false;
529 
530 	id = surf->surface_id;
531 	surf->surface_id = 0;
532 
533 	release->surface_release_id = id;
534 	cmd = (struct qxl_surface_cmd *)qxl_release_map(qdev, release);
535 	cmd->type = QXL_SURFACE_CMD_DESTROY;
536 	cmd->surface_id = id;
537 	qxl_release_unmap(qdev, release, &cmd->release_info);
538 
539 	qxl_release_fence_buffer_objects(release);
540 	qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false);
541 
542 	return 0;
543 }
544 
qxl_update_surface(struct qxl_device * qdev,struct qxl_bo * surf)545 static int qxl_update_surface(struct qxl_device *qdev, struct qxl_bo *surf)
546 {
547 	struct qxl_rect rect;
548 	int ret;
549 
550 	/* if we are evicting, we need to make sure the surface is up
551 	   to date */
552 	rect.left = 0;
553 	rect.right = surf->surf.width;
554 	rect.top = 0;
555 	rect.bottom = surf->surf.height;
556 retry:
557 	ret = qxl_io_update_area(qdev, surf, &rect);
558 	if (ret == -ERESTARTSYS)
559 		goto retry;
560 	return ret;
561 }
562 
qxl_surface_evict_locked(struct qxl_device * qdev,struct qxl_bo * surf,bool do_update_area)563 static void qxl_surface_evict_locked(struct qxl_device *qdev, struct qxl_bo *surf, bool do_update_area)
564 {
565 	/* no need to update area if we are just freeing the surface normally */
566 	if (do_update_area)
567 		qxl_update_surface(qdev, surf);
568 
569 	/* nuke the surface id at the hw */
570 	qxl_hw_surface_dealloc(qdev, surf);
571 }
572 
qxl_surface_evict(struct qxl_device * qdev,struct qxl_bo * surf,bool do_update_area)573 void qxl_surface_evict(struct qxl_device *qdev, struct qxl_bo *surf, bool do_update_area)
574 {
575 	mutex_lock(&qdev->surf_evict_mutex);
576 	qxl_surface_evict_locked(qdev, surf, do_update_area);
577 	mutex_unlock(&qdev->surf_evict_mutex);
578 }
579 
qxl_reap_surf(struct qxl_device * qdev,struct qxl_bo * surf,bool stall)580 static int qxl_reap_surf(struct qxl_device *qdev, struct qxl_bo *surf, bool stall)
581 {
582 	int ret;
583 
584 	ret = qxl_bo_reserve(surf);
585 	if (ret)
586 		return ret;
587 
588 	if (stall)
589 		mutex_unlock(&qdev->surf_evict_mutex);
590 
591 	ret = ttm_bo_wait(&surf->tbo, true, !stall);
592 
593 	if (stall)
594 		mutex_lock(&qdev->surf_evict_mutex);
595 	if (ret) {
596 		qxl_bo_unreserve(surf);
597 		return ret;
598 	}
599 
600 	qxl_surface_evict_locked(qdev, surf, true);
601 	qxl_bo_unreserve(surf);
602 	return 0;
603 }
604 
qxl_reap_surface_id(struct qxl_device * qdev,int max_to_reap)605 static int qxl_reap_surface_id(struct qxl_device *qdev, int max_to_reap)
606 {
607 	int num_reaped = 0;
608 	int i, ret;
609 	bool stall = false;
610 	int start = 0;
611 
612 	mutex_lock(&qdev->surf_evict_mutex);
613 again:
614 
615 	spin_lock(&qdev->surf_id_idr_lock);
616 	start = qdev->last_alloced_surf_id + 1;
617 	spin_unlock(&qdev->surf_id_idr_lock);
618 
619 	for (i = start; i < start + qdev->rom->n_surfaces; i++) {
620 		void *objptr;
621 		int surfid = i % qdev->rom->n_surfaces;
622 
623 		/* this avoids the case where the objects is in the
624 		   idr but has been evicted half way - its makes
625 		   the idr lookup atomic with the eviction */
626 		spin_lock(&qdev->surf_id_idr_lock);
627 		objptr = idr_find(&qdev->surf_id_idr, surfid);
628 		spin_unlock(&qdev->surf_id_idr_lock);
629 
630 		if (!objptr)
631 			continue;
632 
633 		ret = qxl_reap_surf(qdev, objptr, stall);
634 		if (ret == 0)
635 			num_reaped++;
636 		if (num_reaped >= max_to_reap)
637 			break;
638 	}
639 	if (num_reaped == 0 && stall == false) {
640 		stall = true;
641 		goto again;
642 	}
643 
644 	mutex_unlock(&qdev->surf_evict_mutex);
645 	if (num_reaped) {
646 		usleep_range(500, 1000);
647 		qxl_queue_garbage_collect(qdev, true);
648 	}
649 
650 	return 0;
651 }
652