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/drivers/gpu/drm/qxl/qxl_cmd.c

https://gitlab.com/tbwtiot/kernel_source
C | 693 lines | 540 code | 111 blank | 42 comment | 73 complexity | 43ee76fec0427eedc7b45127ab724fe1 MD5 | raw file
  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
 31static int qxl_reap_surface_id(struct qxl_device *qdev, int max_to_reap);
 32
 33struct ring {
 34	struct qxl_ring_header      header;
 35	uint8_t                     elements[0];
 36};
 37
 38struct 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
 47void qxl_ring_free(struct qxl_ring *ring)
 48{
 49	kfree(ring);
 50}
 51
 52void qxl_ring_init_hdr(struct qxl_ring *ring)
 53{
 54	ring->ring->header.notify_on_prod = ring->n_elements;
 55}
 56
 57struct qxl_ring *
 58qxl_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
 82static 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
 95int 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
106int 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
152static 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
177int
178qxl_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
190int
191qxl_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
203bool 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
214int 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
256int 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;
276out_unref:
277	qxl_bo_unref(&bo);
278	return ret;
279}
280
281static 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);
309out:
310	if (ret > 0)
311		ret = 0;
312	mutex_unlock(&qdev->async_io_mutex);
313	return ret;
314}
315
316static void wait_for_io_cmd(struct qxl_device *qdev, uint8_t val, long port)
317{
318	int ret;
319
320restart:
321	ret = wait_for_io_cmd_user(qdev, val, port, false);
322	if (ret == -ERESTARTSYS)
323		goto restart;
324}
325
326int 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
358void qxl_io_notify_oom(struct qxl_device *qdev)
359{
360	outb(0, qdev->io_base + QXL_IO_NOTIFY_OOM);
361}
362
363void qxl_io_flush_release(struct qxl_device *qdev)
364{
365	outb(0, qdev->io_base + QXL_IO_FLUSH_RELEASE);
366}
367
368void qxl_io_flush_surfaces(struct qxl_device *qdev)
369{
370	wait_for_io_cmd(qdev, 0, QXL_IO_FLUSH_SURFACES_ASYNC);
371}
372
373
374void qxl_io_destroy_primary(struct qxl_device *qdev)
375{
376	wait_for_io_cmd(qdev, 0, QXL_IO_DESTROY_PRIMARY_ASYNC);
377}
378
379void 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
402void 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
408void 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
422void qxl_io_reset(struct qxl_device *qdev)
423{
424	outb(0, qdev->io_base + QXL_IO_RESET);
425}
426
427void 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
445int 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;
451again:
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
477void 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
485int 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->u.surface_create.format = surf->surf.format;
509	cmd->u.surface_create.width = surf->surf.width;
510	cmd->u.surface_create.height = surf->surf.height;
511	cmd->u.surface_create.stride = surf->surf.stride;
512	if (new_mem) {
513		int slot_id = surf->type == QXL_GEM_DOMAIN_VRAM ? qdev->main_mem_slot : qdev->surfaces_mem_slot;
514		struct qxl_memslot *slot = &(qdev->mem_slots[slot_id]);
515
516		/* TODO - need to hold one of the locks to read tbo.offset */
517		cmd->u.surface_create.data = slot->high_bits;
518
519		cmd->u.surface_create.data |= (new_mem->start << PAGE_SHIFT) + surf->tbo.bdev->man[new_mem->mem_type].gpu_offset;
520	} else
521		cmd->u.surface_create.data = qxl_bo_physical_address(qdev, surf, 0);
522	cmd->surface_id = surf->surface_id;
523	qxl_release_unmap(qdev, release, &cmd->release_info);
524
525	surf->surf_create = release;
526
527	/* no need to add a release to the fence for this surface bo,
528	   since it is only released when we ask to destroy the surface
529	   and it would never signal otherwise */
530	qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false);
531	qxl_release_fence_buffer_objects(release);
532
533	surf->hw_surf_alloc = true;
534	spin_lock(&qdev->surf_id_idr_lock);
535	idr_replace(&qdev->surf_id_idr, surf, surf->surface_id);
536	spin_unlock(&qdev->surf_id_idr_lock);
537	return 0;
538}
539
540int qxl_hw_surface_dealloc(struct qxl_device *qdev,
541			   struct qxl_bo *surf)
542{
543	struct qxl_surface_cmd *cmd;
544	struct qxl_release *release;
545	int ret;
546	int id;
547
548	if (!surf->hw_surf_alloc)
549		return 0;
550
551	ret = qxl_alloc_surface_release_reserved(qdev, QXL_SURFACE_CMD_DESTROY,
552						 surf->surf_create,
553						 &release);
554	if (ret)
555		return ret;
556
557	surf->surf_create = NULL;
558	/* remove the surface from the idr, but not the surface id yet */
559	spin_lock(&qdev->surf_id_idr_lock);
560	idr_replace(&qdev->surf_id_idr, NULL, surf->surface_id);
561	spin_unlock(&qdev->surf_id_idr_lock);
562	surf->hw_surf_alloc = false;
563
564	id = surf->surface_id;
565	surf->surface_id = 0;
566
567	release->surface_release_id = id;
568	cmd = (struct qxl_surface_cmd *)qxl_release_map(qdev, release);
569	cmd->type = QXL_SURFACE_CMD_DESTROY;
570	cmd->surface_id = id;
571	qxl_release_unmap(qdev, release, &cmd->release_info);
572
573	qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false);
574
575	qxl_release_fence_buffer_objects(release);
576
577	return 0;
578}
579
580int qxl_update_surface(struct qxl_device *qdev, struct qxl_bo *surf)
581{
582	struct qxl_rect rect;
583	int ret;
584
585	/* if we are evicting, we need to make sure the surface is up
586	   to date */
587	rect.left = 0;
588	rect.right = surf->surf.width;
589	rect.top = 0;
590	rect.bottom = surf->surf.height;
591retry:
592	ret = qxl_io_update_area(qdev, surf, &rect);
593	if (ret == -ERESTARTSYS)
594		goto retry;
595	return ret;
596}
597
598static void qxl_surface_evict_locked(struct qxl_device *qdev, struct qxl_bo *surf, bool do_update_area)
599{
600	/* no need to update area if we are just freeing the surface normally */
601	if (do_update_area)
602		qxl_update_surface(qdev, surf);
603
604	/* nuke the surface id at the hw */
605	qxl_hw_surface_dealloc(qdev, surf);
606}
607
608void qxl_surface_evict(struct qxl_device *qdev, struct qxl_bo *surf, bool do_update_area)
609{
610	mutex_lock(&qdev->surf_evict_mutex);
611	qxl_surface_evict_locked(qdev, surf, do_update_area);
612	mutex_unlock(&qdev->surf_evict_mutex);
613}
614
615static int qxl_reap_surf(struct qxl_device *qdev, struct qxl_bo *surf, bool stall)
616{
617	int ret;
618
619	ret = qxl_bo_reserve(surf, false);
620	if (ret == -EBUSY)
621		return -EBUSY;
622
623	if (surf->fence.num_active_releases > 0 && stall == false) {
624		qxl_bo_unreserve(surf);
625		return -EBUSY;
626	}
627
628	if (stall)
629		mutex_unlock(&qdev->surf_evict_mutex);
630
631	spin_lock(&surf->tbo.bdev->fence_lock);
632	ret = ttm_bo_wait(&surf->tbo, true, true, !stall);
633	spin_unlock(&surf->tbo.bdev->fence_lock);
634
635	if (stall)
636		mutex_lock(&qdev->surf_evict_mutex);
637	if (ret == -EBUSY) {
638		qxl_bo_unreserve(surf);
639		return -EBUSY;
640	}
641
642	qxl_surface_evict_locked(qdev, surf, true);
643	qxl_bo_unreserve(surf);
644	return 0;
645}
646
647static int qxl_reap_surface_id(struct qxl_device *qdev, int max_to_reap)
648{
649	int num_reaped = 0;
650	int i, ret;
651	bool stall = false;
652	int start = 0;
653
654	mutex_lock(&qdev->surf_evict_mutex);
655again:
656
657	spin_lock(&qdev->surf_id_idr_lock);
658	start = qdev->last_alloced_surf_id + 1;
659	spin_unlock(&qdev->surf_id_idr_lock);
660
661	for (i = start; i < start + qdev->rom->n_surfaces; i++) {
662		void *objptr;
663		int surfid = i % qdev->rom->n_surfaces;
664
665		/* this avoids the case where the objects is in the
666		   idr but has been evicted half way - its makes
667		   the idr lookup atomic with the eviction */
668		spin_lock(&qdev->surf_id_idr_lock);
669		objptr = idr_find(&qdev->surf_id_idr, surfid);
670		spin_unlock(&qdev->surf_id_idr_lock);
671
672		if (!objptr)
673			continue;
674
675		ret = qxl_reap_surf(qdev, objptr, stall);
676		if (ret == 0)
677			num_reaped++;
678		if (num_reaped >= max_to_reap)
679			break;
680	}
681	if (num_reaped == 0 && stall == false) {
682		stall = true;
683		goto again;
684	}
685
686	mutex_unlock(&qdev->surf_evict_mutex);
687	if (num_reaped) {
688		usleep_range(500, 1000);
689		qxl_queue_garbage_collect(qdev, true);
690	}
691
692	return 0;
693}