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
35static int qxl_reap_surface_id(struct qxl_device *qdev, int max_to_reap);
36
37struct ring {
38	struct qxl_ring_header      header;
39	uint8_t                     elements[];
40};
41
42struct 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
51void qxl_ring_free(struct qxl_ring *ring)
52{
53	kfree(ring);
54}
55
56struct qxl_ring *
57qxl_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
78static 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
92int 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
104int 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
151static 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
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
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
189int
190qxl_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
201bool 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
212int 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
255int 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;
275out_unref:
276	qxl_bo_unref(&bo);
277	return ret;
278}
279
280static 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);
308out:
309	if (ret > 0)
310		ret = 0;
311	mutex_unlock(&qdev->async_io_mutex);
312	return ret;
313}
314
315static void wait_for_io_cmd(struct qxl_device *qdev, uint8_t val, long port)
316{
317	int ret;
318
319restart:
320	ret = wait_for_io_cmd_user(qdev, val, port, false);
321	if (ret == -ERESTARTSYS)
322		goto restart;
323}
324
325int 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
354void qxl_io_notify_oom(struct qxl_device *qdev)
355{
356	outb(0, qdev->io_base + QXL_IO_NOTIFY_OOM);
357}
358
359void qxl_io_flush_release(struct qxl_device *qdev)
360{
361	outb(0, qdev->io_base + QXL_IO_FLUSH_RELEASE);
362}
363
364void qxl_io_flush_surfaces(struct qxl_device *qdev)
365{
366	wait_for_io_cmd(qdev, 0, QXL_IO_FLUSH_SURFACES_ASYNC);
367}
368
369void 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
377void 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
403void 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
409void qxl_io_reset(struct qxl_device *qdev)
410{
411	outb(0, qdev->io_base + QXL_IO_RESET);
412}
413
414void qxl_io_monitors_config(struct qxl_device *qdev)
415{
416	wait_for_io_cmd(qdev, 0, QXL_IO_MONITORS_CONFIG_ASYNC);
417}
418
419int qxl_surface_id_alloc(struct qxl_device *qdev,
420		      struct qxl_bo *surf)
421{
422	uint32_t handle;
423	int idr_ret;
424again:
425	idr_preload(GFP_ATOMIC);
426	spin_lock(&qdev->surf_id_idr_lock);
427	idr_ret = idr_alloc(&qdev->surf_id_idr, NULL, 1, 0, GFP_NOWAIT);
428	spin_unlock(&qdev->surf_id_idr_lock);
429	idr_preload_end();
430	if (idr_ret < 0)
431		return idr_ret;
432	handle = idr_ret;
433
434	if (handle >= qdev->rom->n_surfaces) {
435		spin_lock(&qdev->surf_id_idr_lock);
436		idr_remove(&qdev->surf_id_idr, handle);
437		spin_unlock(&qdev->surf_id_idr_lock);
438		qxl_reap_surface_id(qdev, 2);
439		goto again;
440	}
441	surf->surface_id = handle;
442
443	spin_lock(&qdev->surf_id_idr_lock);
444	qdev->last_alloced_surf_id = handle;
445	spin_unlock(&qdev->surf_id_idr_lock);
446	return 0;
447}
448
449void qxl_surface_id_dealloc(struct qxl_device *qdev,
450			    uint32_t surface_id)
451{
452	spin_lock(&qdev->surf_id_idr_lock);
453	idr_remove(&qdev->surf_id_idr, surface_id);
454	spin_unlock(&qdev->surf_id_idr_lock);
455}
456
457int qxl_hw_surface_alloc(struct qxl_device *qdev,
458			 struct qxl_bo *surf)
459{
460	struct qxl_surface_cmd *cmd;
461	struct qxl_release *release;
462	int ret;
463
464	if (surf->hw_surf_alloc)
465		return 0;
466
467	ret = qxl_alloc_surface_release_reserved(qdev, QXL_SURFACE_CMD_CREATE,
468						 NULL,
469						 &release);
470	if (ret)
471		return ret;
472
473	ret = qxl_release_reserve_list(release, true);
474	if (ret) {
475		qxl_release_free(qdev, release);
476		return ret;
477	}
478	cmd = (struct qxl_surface_cmd *)qxl_release_map(qdev, release);
479	cmd->type = QXL_SURFACE_CMD_CREATE;
480	cmd->flags = QXL_SURF_FLAG_KEEP_DATA;
481	cmd->u.surface_create.format = surf->surf.format;
482	cmd->u.surface_create.width = surf->surf.width;
483	cmd->u.surface_create.height = surf->surf.height;
484	cmd->u.surface_create.stride = surf->surf.stride;
485	cmd->u.surface_create.data = qxl_bo_physical_address(qdev, surf, 0);
486	cmd->surface_id = surf->surface_id;
487	qxl_release_unmap(qdev, release, &cmd->release_info);
488
489	surf->surf_create = release;
490
491	/* no need to add a release to the fence for this surface bo,
492	   since it is only released when we ask to destroy the surface
493	   and it would never signal otherwise */
494	qxl_release_fence_buffer_objects(release);
495	qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false);
496
497	surf->hw_surf_alloc = true;
498	spin_lock(&qdev->surf_id_idr_lock);
499	idr_replace(&qdev->surf_id_idr, surf, surf->surface_id);
500	spin_unlock(&qdev->surf_id_idr_lock);
501	return 0;
502}
503
504int qxl_hw_surface_dealloc(struct qxl_device *qdev,
505			   struct qxl_bo *surf)
506{
507	struct qxl_surface_cmd *cmd;
508	struct qxl_release *release;
509	int ret;
510	int id;
511
512	if (!surf->hw_surf_alloc)
513		return 0;
514
515	ret = qxl_alloc_surface_release_reserved(qdev, QXL_SURFACE_CMD_DESTROY,
516						 surf->surf_create,
517						 &release);
518	if (ret)
519		return ret;
520
521	surf->surf_create = NULL;
522	/* remove the surface from the idr, but not the surface id yet */
523	spin_lock(&qdev->surf_id_idr_lock);
524	idr_replace(&qdev->surf_id_idr, NULL, surf->surface_id);
525	spin_unlock(&qdev->surf_id_idr_lock);
526	surf->hw_surf_alloc = false;
527
528	id = surf->surface_id;
529	surf->surface_id = 0;
530
531	release->surface_release_id = id;
532	cmd = (struct qxl_surface_cmd *)qxl_release_map(qdev, release);
533	cmd->type = QXL_SURFACE_CMD_DESTROY;
534	cmd->surface_id = id;
535	qxl_release_unmap(qdev, release, &cmd->release_info);
536
537	qxl_release_fence_buffer_objects(release);
538	qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false);
539
540	return 0;
541}
542
543static int qxl_update_surface(struct qxl_device *qdev, struct qxl_bo *surf)
544{
545	struct qxl_rect rect;
546	int ret;
547
548	/* if we are evicting, we need to make sure the surface is up
549	   to date */
550	rect.left = 0;
551	rect.right = surf->surf.width;
552	rect.top = 0;
553	rect.bottom = surf->surf.height;
554retry:
555	ret = qxl_io_update_area(qdev, surf, &rect);
556	if (ret == -ERESTARTSYS)
557		goto retry;
558	return ret;
559}
560
561static void qxl_surface_evict_locked(struct qxl_device *qdev, struct qxl_bo *surf, bool do_update_area)
562{
563	/* no need to update area if we are just freeing the surface normally */
564	if (do_update_area)
565		qxl_update_surface(qdev, surf);
566
567	/* nuke the surface id at the hw */
568	qxl_hw_surface_dealloc(qdev, surf);
569}
570
571void qxl_surface_evict(struct qxl_device *qdev, struct qxl_bo *surf, bool do_update_area)
572{
573	mutex_lock(&qdev->surf_evict_mutex);
574	qxl_surface_evict_locked(qdev, surf, do_update_area);
575	mutex_unlock(&qdev->surf_evict_mutex);
576}
577
578static int qxl_reap_surf(struct qxl_device *qdev, struct qxl_bo *surf, bool stall)
579{
580	long ret;
581
582	ret = qxl_bo_reserve(surf);
583	if (ret)
584		return ret;
585
586	if (stall)
587		mutex_unlock(&qdev->surf_evict_mutex);
588
589	if (stall) {
590		ret = dma_resv_wait_timeout(surf->tbo.base.resv,
591					    DMA_RESV_USAGE_BOOKKEEP, true,
592					    15 * HZ);
593		if (ret > 0)
594			ret = 0;
595		else if (ret == 0)
596			ret = -EBUSY;
597	} else {
598		ret = dma_resv_test_signaled(surf->tbo.base.resv,
599					     DMA_RESV_USAGE_BOOKKEEP);
600		ret = ret ? -EBUSY : 0;
601	}
602
603	if (stall)
604		mutex_lock(&qdev->surf_evict_mutex);
605	if (ret) {
606		qxl_bo_unreserve(surf);
607		return ret;
608	}
609
610	qxl_surface_evict_locked(qdev, surf, true);
611	qxl_bo_unreserve(surf);
612	return 0;
613}
614
615static int qxl_reap_surface_id(struct qxl_device *qdev, int max_to_reap)
616{
617	int num_reaped = 0;
618	int i, ret;
619	bool stall = false;
620	int start = 0;
621
622	mutex_lock(&qdev->surf_evict_mutex);
623again:
624
625	spin_lock(&qdev->surf_id_idr_lock);
626	start = qdev->last_alloced_surf_id + 1;
627	spin_unlock(&qdev->surf_id_idr_lock);
628
629	for (i = start; i < start + qdev->rom->n_surfaces; i++) {
630		void *objptr;
631		int surfid = i % qdev->rom->n_surfaces;
632
633		/* this avoids the case where the objects is in the
634		   idr but has been evicted half way - its makes
635		   the idr lookup atomic with the eviction */
636		spin_lock(&qdev->surf_id_idr_lock);
637		objptr = idr_find(&qdev->surf_id_idr, surfid);
638		spin_unlock(&qdev->surf_id_idr_lock);
639
640		if (!objptr)
641			continue;
642
643		ret = qxl_reap_surf(qdev, objptr, stall);
644		if (ret == 0)
645			num_reaped++;
646		if (num_reaped >= max_to_reap)
647			break;
648	}
649	if (num_reaped == 0 && stall == false) {
650		stall = true;
651		goto again;
652	}
653
654	mutex_unlock(&qdev->surf_evict_mutex);
655	if (num_reaped) {
656		usleep_range(500, 1000);
657		qxl_queue_garbage_collect(qdev, true);
658	}
659
660	return 0;
661}
662