2 * videobuf2-core.c - V4L2 driver helper framework
4 * Copyright (C) 2010 Samsung Electronics
6 * Author: Pawel Osciak <pawel@osciak.com>
7 * Marek Szyprowski <m.szyprowski@samsung.com>
9 * The vb2_thread implementation was based on code from videobuf-dvb.c:
10 * (c) 2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs]
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation.
17 #include <linux/err.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
21 #include <linux/poll.h>
22 #include <linux/slab.h>
23 #include <linux/sched.h>
24 #include <linux/freezer.h>
25 #include <linux/kthread.h>
27 #include <media/v4l2-dev.h>
28 #include <media/v4l2-fh.h>
29 #include <media/v4l2-event.h>
30 #include <media/v4l2-common.h>
31 #include <media/videobuf2-core.h>
34 module_param(debug
, int, 0644);
36 #define dprintk(level, fmt, arg...) \
39 pr_info("vb2: %s: " fmt, __func__, ## arg); \
42 #ifdef CONFIG_VIDEO_ADV_DEBUG
45 * If advanced debugging is on, then count how often each op is called
46 * successfully, which can either be per-buffer or per-queue.
48 * This makes it easy to check that the 'init' and 'cleanup'
49 * (and variations thereof) stay balanced.
52 #define log_memop(vb, op) \
53 dprintk(2, "call_memop(%p, %d, %s)%s\n", \
54 (vb)->vb2_queue, (vb)->v4l2_buf.index, #op, \
55 (vb)->vb2_queue->mem_ops->op ? "" : " (nop)")
57 #define call_memop(vb, op, args...) \
59 struct vb2_queue *_q = (vb)->vb2_queue; \
63 err = _q->mem_ops->op ? _q->mem_ops->op(args) : 0; \
65 (vb)->cnt_mem_ ## op++; \
69 #define call_ptr_memop(vb, op, args...) \
71 struct vb2_queue *_q = (vb)->vb2_queue; \
75 ptr = _q->mem_ops->op ? _q->mem_ops->op(args) : NULL; \
76 if (!IS_ERR_OR_NULL(ptr)) \
77 (vb)->cnt_mem_ ## op++; \
81 #define call_void_memop(vb, op, args...) \
83 struct vb2_queue *_q = (vb)->vb2_queue; \
86 if (_q->mem_ops->op) \
87 _q->mem_ops->op(args); \
88 (vb)->cnt_mem_ ## op++; \
91 #define log_qop(q, op) \
92 dprintk(2, "call_qop(%p, %s)%s\n", q, #op, \
93 (q)->ops->op ? "" : " (nop)")
95 #define call_qop(q, op, args...) \
100 err = (q)->ops->op ? (q)->ops->op(args) : 0; \
106 #define call_void_qop(q, op, args...) \
110 (q)->ops->op(args); \
114 #define log_vb_qop(vb, op, args...) \
115 dprintk(2, "call_vb_qop(%p, %d, %s)%s\n", \
116 (vb)->vb2_queue, (vb)->v4l2_buf.index, #op, \
117 (vb)->vb2_queue->ops->op ? "" : " (nop)")
119 #define call_vb_qop(vb, op, args...) \
123 log_vb_qop(vb, op); \
124 err = (vb)->vb2_queue->ops->op ? \
125 (vb)->vb2_queue->ops->op(args) : 0; \
127 (vb)->cnt_ ## op++; \
131 #define call_void_vb_qop(vb, op, args...) \
133 log_vb_qop(vb, op); \
134 if ((vb)->vb2_queue->ops->op) \
135 (vb)->vb2_queue->ops->op(args); \
136 (vb)->cnt_ ## op++; \
141 #define call_memop(vb, op, args...) \
142 ((vb)->vb2_queue->mem_ops->op ? \
143 (vb)->vb2_queue->mem_ops->op(args) : 0)
145 #define call_ptr_memop(vb, op, args...) \
146 ((vb)->vb2_queue->mem_ops->op ? \
147 (vb)->vb2_queue->mem_ops->op(args) : NULL)
149 #define call_void_memop(vb, op, args...) \
151 if ((vb)->vb2_queue->mem_ops->op) \
152 (vb)->vb2_queue->mem_ops->op(args); \
155 #define call_qop(q, op, args...) \
156 ((q)->ops->op ? (q)->ops->op(args) : 0)
158 #define call_void_qop(q, op, args...) \
161 (q)->ops->op(args); \
164 #define call_vb_qop(vb, op, args...) \
165 ((vb)->vb2_queue->ops->op ? (vb)->vb2_queue->ops->op(args) : 0)
167 #define call_void_vb_qop(vb, op, args...) \
169 if ((vb)->vb2_queue->ops->op) \
170 (vb)->vb2_queue->ops->op(args); \
175 /* Flags that are set by the vb2 core */
176 #define V4L2_BUFFER_MASK_FLAGS (V4L2_BUF_FLAG_MAPPED | V4L2_BUF_FLAG_QUEUED | \
177 V4L2_BUF_FLAG_DONE | V4L2_BUF_FLAG_ERROR | \
178 V4L2_BUF_FLAG_PREPARED | \
179 V4L2_BUF_FLAG_TIMESTAMP_MASK)
180 /* Output buffer flags that should be passed on to the driver */
181 #define V4L2_BUFFER_OUT_FLAGS (V4L2_BUF_FLAG_PFRAME | V4L2_BUF_FLAG_BFRAME | \
182 V4L2_BUF_FLAG_KEYFRAME | V4L2_BUF_FLAG_TIMECODE)
184 static void __vb2_queue_cancel(struct vb2_queue
*q
);
185 static void __enqueue_in_driver(struct vb2_buffer
*vb
);
188 * __vb2_buf_mem_alloc() - allocate video memory for the given buffer
190 static int __vb2_buf_mem_alloc(struct vb2_buffer
*vb
)
192 struct vb2_queue
*q
= vb
->vb2_queue
;
193 enum dma_data_direction dma_dir
=
194 V4L2_TYPE_IS_OUTPUT(q
->type
) ? DMA_TO_DEVICE
: DMA_FROM_DEVICE
;
199 * Allocate memory for all planes in this buffer
200 * NOTE: mmapped areas should be page aligned
202 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
203 unsigned long size
= PAGE_ALIGN(q
->plane_sizes
[plane
]);
205 mem_priv
= call_ptr_memop(vb
, alloc
, q
->alloc_ctx
[plane
],
206 size
, dma_dir
, q
->gfp_flags
);
207 if (IS_ERR_OR_NULL(mem_priv
))
210 /* Associate allocator private data with this plane */
211 vb
->planes
[plane
].mem_priv
= mem_priv
;
212 vb
->v4l2_planes
[plane
].length
= q
->plane_sizes
[plane
];
217 /* Free already allocated memory if one of the allocations failed */
218 for (; plane
> 0; --plane
) {
219 call_void_memop(vb
, put
, vb
->planes
[plane
- 1].mem_priv
);
220 vb
->planes
[plane
- 1].mem_priv
= NULL
;
227 * __vb2_buf_mem_free() - free memory of the given buffer
229 static void __vb2_buf_mem_free(struct vb2_buffer
*vb
)
233 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
234 call_void_memop(vb
, put
, vb
->planes
[plane
].mem_priv
);
235 vb
->planes
[plane
].mem_priv
= NULL
;
236 dprintk(3, "freed plane %d of buffer %d\n", plane
,
242 * __vb2_buf_userptr_put() - release userspace memory associated with
245 static void __vb2_buf_userptr_put(struct vb2_buffer
*vb
)
249 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
250 if (vb
->planes
[plane
].mem_priv
)
251 call_void_memop(vb
, put_userptr
, vb
->planes
[plane
].mem_priv
);
252 vb
->planes
[plane
].mem_priv
= NULL
;
257 * __vb2_plane_dmabuf_put() - release memory associated with
258 * a DMABUF shared plane
260 static void __vb2_plane_dmabuf_put(struct vb2_buffer
*vb
, struct vb2_plane
*p
)
266 call_void_memop(vb
, unmap_dmabuf
, p
->mem_priv
);
268 call_void_memop(vb
, detach_dmabuf
, p
->mem_priv
);
269 dma_buf_put(p
->dbuf
);
270 memset(p
, 0, sizeof(*p
));
274 * __vb2_buf_dmabuf_put() - release memory associated with
275 * a DMABUF shared buffer
277 static void __vb2_buf_dmabuf_put(struct vb2_buffer
*vb
)
281 for (plane
= 0; plane
< vb
->num_planes
; ++plane
)
282 __vb2_plane_dmabuf_put(vb
, &vb
->planes
[plane
]);
286 * __setup_lengths() - setup initial lengths for every plane in
287 * every buffer on the queue
289 static void __setup_lengths(struct vb2_queue
*q
, unsigned int n
)
291 unsigned int buffer
, plane
;
292 struct vb2_buffer
*vb
;
294 for (buffer
= q
->num_buffers
; buffer
< q
->num_buffers
+ n
; ++buffer
) {
295 vb
= q
->bufs
[buffer
];
299 for (plane
= 0; plane
< vb
->num_planes
; ++plane
)
300 vb
->v4l2_planes
[plane
].length
= q
->plane_sizes
[plane
];
305 * __setup_offsets() - setup unique offsets ("cookies") for every plane in
306 * every buffer on the queue
308 static void __setup_offsets(struct vb2_queue
*q
, unsigned int n
)
310 unsigned int buffer
, plane
;
311 struct vb2_buffer
*vb
;
314 if (q
->num_buffers
) {
315 struct v4l2_plane
*p
;
316 vb
= q
->bufs
[q
->num_buffers
- 1];
317 p
= &vb
->v4l2_planes
[vb
->num_planes
- 1];
318 off
= PAGE_ALIGN(p
->m
.mem_offset
+ p
->length
);
323 for (buffer
= q
->num_buffers
; buffer
< q
->num_buffers
+ n
; ++buffer
) {
324 vb
= q
->bufs
[buffer
];
328 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
329 vb
->v4l2_planes
[plane
].m
.mem_offset
= off
;
331 dprintk(3, "buffer %d, plane %d offset 0x%08lx\n",
334 off
+= vb
->v4l2_planes
[plane
].length
;
335 off
= PAGE_ALIGN(off
);
341 * __vb2_queue_alloc() - allocate videobuf buffer structures and (for MMAP type)
342 * video buffer memory for all buffers/planes on the queue and initializes the
345 * Returns the number of buffers successfully allocated.
347 static int __vb2_queue_alloc(struct vb2_queue
*q
, enum v4l2_memory memory
,
348 unsigned int num_buffers
, unsigned int num_planes
)
351 struct vb2_buffer
*vb
;
354 for (buffer
= 0; buffer
< num_buffers
; ++buffer
) {
355 /* Allocate videobuf buffer structures */
356 vb
= kzalloc(q
->buf_struct_size
, GFP_KERNEL
);
358 dprintk(1, "memory alloc for buffer struct failed\n");
362 /* Length stores number of planes for multiplanar buffers */
363 if (V4L2_TYPE_IS_MULTIPLANAR(q
->type
))
364 vb
->v4l2_buf
.length
= num_planes
;
366 vb
->state
= VB2_BUF_STATE_DEQUEUED
;
368 vb
->num_planes
= num_planes
;
369 vb
->v4l2_buf
.index
= q
->num_buffers
+ buffer
;
370 vb
->v4l2_buf
.type
= q
->type
;
371 vb
->v4l2_buf
.memory
= memory
;
373 /* Allocate video buffer memory for the MMAP type */
374 if (memory
== V4L2_MEMORY_MMAP
) {
375 ret
= __vb2_buf_mem_alloc(vb
);
377 dprintk(1, "failed allocating memory for "
378 "buffer %d\n", buffer
);
383 * Call the driver-provided buffer initialization
384 * callback, if given. An error in initialization
385 * results in queue setup failure.
387 ret
= call_vb_qop(vb
, buf_init
, vb
);
389 dprintk(1, "buffer %d %p initialization"
390 " failed\n", buffer
, vb
);
391 __vb2_buf_mem_free(vb
);
397 q
->bufs
[q
->num_buffers
+ buffer
] = vb
;
400 __setup_lengths(q
, buffer
);
401 if (memory
== V4L2_MEMORY_MMAP
)
402 __setup_offsets(q
, buffer
);
404 dprintk(1, "allocated %d buffers, %d plane(s) each\n",
411 * __vb2_free_mem() - release all video buffer memory for a given queue
413 static void __vb2_free_mem(struct vb2_queue
*q
, unsigned int buffers
)
416 struct vb2_buffer
*vb
;
418 for (buffer
= q
->num_buffers
- buffers
; buffer
< q
->num_buffers
;
420 vb
= q
->bufs
[buffer
];
424 /* Free MMAP buffers or release USERPTR buffers */
425 if (q
->memory
== V4L2_MEMORY_MMAP
)
426 __vb2_buf_mem_free(vb
);
427 else if (q
->memory
== V4L2_MEMORY_DMABUF
)
428 __vb2_buf_dmabuf_put(vb
);
430 __vb2_buf_userptr_put(vb
);
435 * __vb2_queue_free() - free buffers at the end of the queue - video memory and
436 * related information, if no buffers are left return the queue to an
437 * uninitialized state. Might be called even if the queue has already been freed.
439 static int __vb2_queue_free(struct vb2_queue
*q
, unsigned int buffers
)
444 * Sanity check: when preparing a buffer the queue lock is released for
445 * a short while (see __buf_prepare for the details), which would allow
446 * a race with a reqbufs which can call this function. Removing the
447 * buffers from underneath __buf_prepare is obviously a bad idea, so we
448 * check if any of the buffers is in the state PREPARING, and if so we
449 * just return -EAGAIN.
451 for (buffer
= q
->num_buffers
- buffers
; buffer
< q
->num_buffers
;
453 if (q
->bufs
[buffer
] == NULL
)
455 if (q
->bufs
[buffer
]->state
== VB2_BUF_STATE_PREPARING
) {
456 dprintk(1, "preparing buffers, cannot free\n");
461 /* Call driver-provided cleanup function for each buffer, if provided */
462 for (buffer
= q
->num_buffers
- buffers
; buffer
< q
->num_buffers
;
464 struct vb2_buffer
*vb
= q
->bufs
[buffer
];
466 if (vb
&& vb
->planes
[0].mem_priv
)
467 call_void_vb_qop(vb
, buf_cleanup
, vb
);
470 /* Release video buffer memory */
471 __vb2_free_mem(q
, buffers
);
473 #ifdef CONFIG_VIDEO_ADV_DEBUG
475 * Check that all the calls were balances during the life-time of this
476 * queue. If not (or if the debug level is 1 or up), then dump the
477 * counters to the kernel log.
479 if (q
->num_buffers
) {
480 bool unbalanced
= q
->cnt_start_streaming
!= q
->cnt_stop_streaming
||
481 q
->cnt_wait_prepare
!= q
->cnt_wait_finish
;
483 if (unbalanced
|| debug
) {
484 pr_info("vb2: counters for queue %p:%s\n", q
,
485 unbalanced
? " UNBALANCED!" : "");
486 pr_info("vb2: setup: %u start_streaming: %u stop_streaming: %u\n",
487 q
->cnt_queue_setup
, q
->cnt_start_streaming
,
488 q
->cnt_stop_streaming
);
489 pr_info("vb2: wait_prepare: %u wait_finish: %u\n",
490 q
->cnt_wait_prepare
, q
->cnt_wait_finish
);
492 q
->cnt_queue_setup
= 0;
493 q
->cnt_wait_prepare
= 0;
494 q
->cnt_wait_finish
= 0;
495 q
->cnt_start_streaming
= 0;
496 q
->cnt_stop_streaming
= 0;
498 for (buffer
= 0; buffer
< q
->num_buffers
; ++buffer
) {
499 struct vb2_buffer
*vb
= q
->bufs
[buffer
];
500 bool unbalanced
= vb
->cnt_mem_alloc
!= vb
->cnt_mem_put
||
501 vb
->cnt_mem_prepare
!= vb
->cnt_mem_finish
||
502 vb
->cnt_mem_get_userptr
!= vb
->cnt_mem_put_userptr
||
503 vb
->cnt_mem_attach_dmabuf
!= vb
->cnt_mem_detach_dmabuf
||
504 vb
->cnt_mem_map_dmabuf
!= vb
->cnt_mem_unmap_dmabuf
||
505 vb
->cnt_buf_queue
!= vb
->cnt_buf_done
||
506 vb
->cnt_buf_prepare
!= vb
->cnt_buf_finish
||
507 vb
->cnt_buf_init
!= vb
->cnt_buf_cleanup
;
509 if (unbalanced
|| debug
) {
510 pr_info("vb2: counters for queue %p, buffer %d:%s\n",
511 q
, buffer
, unbalanced
? " UNBALANCED!" : "");
512 pr_info("vb2: buf_init: %u buf_cleanup: %u buf_prepare: %u buf_finish: %u\n",
513 vb
->cnt_buf_init
, vb
->cnt_buf_cleanup
,
514 vb
->cnt_buf_prepare
, vb
->cnt_buf_finish
);
515 pr_info("vb2: buf_queue: %u buf_done: %u\n",
516 vb
->cnt_buf_queue
, vb
->cnt_buf_done
);
517 pr_info("vb2: alloc: %u put: %u prepare: %u finish: %u mmap: %u\n",
518 vb
->cnt_mem_alloc
, vb
->cnt_mem_put
,
519 vb
->cnt_mem_prepare
, vb
->cnt_mem_finish
,
521 pr_info("vb2: get_userptr: %u put_userptr: %u\n",
522 vb
->cnt_mem_get_userptr
, vb
->cnt_mem_put_userptr
);
523 pr_info("vb2: attach_dmabuf: %u detach_dmabuf: %u map_dmabuf: %u unmap_dmabuf: %u\n",
524 vb
->cnt_mem_attach_dmabuf
, vb
->cnt_mem_detach_dmabuf
,
525 vb
->cnt_mem_map_dmabuf
, vb
->cnt_mem_unmap_dmabuf
);
526 pr_info("vb2: get_dmabuf: %u num_users: %u vaddr: %u cookie: %u\n",
527 vb
->cnt_mem_get_dmabuf
,
528 vb
->cnt_mem_num_users
,
535 /* Free videobuf buffers */
536 for (buffer
= q
->num_buffers
- buffers
; buffer
< q
->num_buffers
;
538 kfree(q
->bufs
[buffer
]);
539 q
->bufs
[buffer
] = NULL
;
542 q
->num_buffers
-= buffers
;
543 if (!q
->num_buffers
) {
545 INIT_LIST_HEAD(&q
->queued_list
);
551 * __verify_planes_array() - verify that the planes array passed in struct
552 * v4l2_buffer from userspace can be safely used
554 static int __verify_planes_array(struct vb2_buffer
*vb
, const struct v4l2_buffer
*b
)
556 if (!V4L2_TYPE_IS_MULTIPLANAR(b
->type
))
559 /* Is memory for copying plane information present? */
560 if (NULL
== b
->m
.planes
) {
561 dprintk(1, "multi-planar buffer passed but "
562 "planes array not provided\n");
566 if (b
->length
< vb
->num_planes
|| b
->length
> VIDEO_MAX_PLANES
) {
567 dprintk(1, "incorrect planes array length, "
568 "expected %d, got %d\n", vb
->num_planes
, b
->length
);
576 * __verify_length() - Verify that the bytesused value for each plane fits in
577 * the plane length and that the data offset doesn't exceed the bytesused value.
579 static int __verify_length(struct vb2_buffer
*vb
, const struct v4l2_buffer
*b
)
582 unsigned int bytesused
;
585 if (!V4L2_TYPE_IS_OUTPUT(b
->type
))
588 if (V4L2_TYPE_IS_MULTIPLANAR(b
->type
)) {
589 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
590 length
= (b
->memory
== V4L2_MEMORY_USERPTR
||
591 b
->memory
== V4L2_MEMORY_DMABUF
)
592 ? b
->m
.planes
[plane
].length
593 : vb
->v4l2_planes
[plane
].length
;
594 bytesused
= b
->m
.planes
[plane
].bytesused
595 ? b
->m
.planes
[plane
].bytesused
: length
;
597 if (b
->m
.planes
[plane
].bytesused
> length
)
600 if (b
->m
.planes
[plane
].data_offset
> 0 &&
601 b
->m
.planes
[plane
].data_offset
>= bytesused
)
605 length
= (b
->memory
== V4L2_MEMORY_USERPTR
)
606 ? b
->length
: vb
->v4l2_planes
[0].length
;
607 bytesused
= b
->bytesused
? b
->bytesused
: length
;
609 if (b
->bytesused
> length
)
617 * __buffer_in_use() - return true if the buffer is in use and
618 * the queue cannot be freed (by the means of REQBUFS(0)) call
620 static bool __buffer_in_use(struct vb2_queue
*q
, struct vb2_buffer
*vb
)
623 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
624 void *mem_priv
= vb
->planes
[plane
].mem_priv
;
626 * If num_users() has not been provided, call_memop
627 * will return 0, apparently nobody cares about this
628 * case anyway. If num_users() returns more than 1,
629 * we are not the only user of the plane's memory.
631 if (mem_priv
&& call_memop(vb
, num_users
, mem_priv
) > 1)
638 * __buffers_in_use() - return true if any buffers on the queue are in use and
639 * the queue cannot be freed (by the means of REQBUFS(0)) call
641 static bool __buffers_in_use(struct vb2_queue
*q
)
644 for (buffer
= 0; buffer
< q
->num_buffers
; ++buffer
) {
645 if (__buffer_in_use(q
, q
->bufs
[buffer
]))
652 * __fill_v4l2_buffer() - fill in a struct v4l2_buffer with information to be
653 * returned to userspace
655 static void __fill_v4l2_buffer(struct vb2_buffer
*vb
, struct v4l2_buffer
*b
)
657 struct vb2_queue
*q
= vb
->vb2_queue
;
659 /* Copy back data such as timestamp, flags, etc. */
660 memcpy(b
, &vb
->v4l2_buf
, offsetof(struct v4l2_buffer
, m
));
661 b
->reserved2
= vb
->v4l2_buf
.reserved2
;
662 b
->reserved
= vb
->v4l2_buf
.reserved
;
664 if (V4L2_TYPE_IS_MULTIPLANAR(q
->type
)) {
666 * Fill in plane-related data if userspace provided an array
667 * for it. The caller has already verified memory and size.
669 b
->length
= vb
->num_planes
;
670 memcpy(b
->m
.planes
, vb
->v4l2_planes
,
671 b
->length
* sizeof(struct v4l2_plane
));
674 * We use length and offset in v4l2_planes array even for
675 * single-planar buffers, but userspace does not.
677 b
->length
= vb
->v4l2_planes
[0].length
;
678 b
->bytesused
= vb
->v4l2_planes
[0].bytesused
;
679 if (q
->memory
== V4L2_MEMORY_MMAP
)
680 b
->m
.offset
= vb
->v4l2_planes
[0].m
.mem_offset
;
681 else if (q
->memory
== V4L2_MEMORY_USERPTR
)
682 b
->m
.userptr
= vb
->v4l2_planes
[0].m
.userptr
;
683 else if (q
->memory
== V4L2_MEMORY_DMABUF
)
684 b
->m
.fd
= vb
->v4l2_planes
[0].m
.fd
;
688 * Clear any buffer state related flags.
690 b
->flags
&= ~V4L2_BUFFER_MASK_FLAGS
;
691 b
->flags
|= q
->timestamp_flags
& V4L2_BUF_FLAG_TIMESTAMP_MASK
;
692 if ((q
->timestamp_flags
& V4L2_BUF_FLAG_TIMESTAMP_MASK
) !=
693 V4L2_BUF_FLAG_TIMESTAMP_COPY
) {
695 * For non-COPY timestamps, drop timestamp source bits
696 * and obtain the timestamp source from the queue.
698 b
->flags
&= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK
;
699 b
->flags
|= q
->timestamp_flags
& V4L2_BUF_FLAG_TSTAMP_SRC_MASK
;
703 case VB2_BUF_STATE_QUEUED
:
704 case VB2_BUF_STATE_ACTIVE
:
705 b
->flags
|= V4L2_BUF_FLAG_QUEUED
;
707 case VB2_BUF_STATE_ERROR
:
708 b
->flags
|= V4L2_BUF_FLAG_ERROR
;
710 case VB2_BUF_STATE_DONE
:
711 b
->flags
|= V4L2_BUF_FLAG_DONE
;
713 case VB2_BUF_STATE_PREPARED
:
714 b
->flags
|= V4L2_BUF_FLAG_PREPARED
;
716 case VB2_BUF_STATE_PREPARING
:
717 case VB2_BUF_STATE_DEQUEUED
:
722 if (__buffer_in_use(q
, vb
))
723 b
->flags
|= V4L2_BUF_FLAG_MAPPED
;
727 * vb2_querybuf() - query video buffer information
729 * @b: buffer struct passed from userspace to vidioc_querybuf handler
732 * Should be called from vidioc_querybuf ioctl handler in driver.
733 * This function will verify the passed v4l2_buffer structure and fill the
734 * relevant information for the userspace.
736 * The return values from this function are intended to be directly returned
737 * from vidioc_querybuf handler in driver.
739 int vb2_querybuf(struct vb2_queue
*q
, struct v4l2_buffer
*b
)
741 struct vb2_buffer
*vb
;
744 if (b
->type
!= q
->type
) {
745 dprintk(1, "wrong buffer type\n");
749 if (b
->index
>= q
->num_buffers
) {
750 dprintk(1, "buffer index out of range\n");
753 vb
= q
->bufs
[b
->index
];
754 ret
= __verify_planes_array(vb
, b
);
756 __fill_v4l2_buffer(vb
, b
);
759 EXPORT_SYMBOL(vb2_querybuf
);
762 * __verify_userptr_ops() - verify that all memory operations required for
763 * USERPTR queue type have been provided
765 static int __verify_userptr_ops(struct vb2_queue
*q
)
767 if (!(q
->io_modes
& VB2_USERPTR
) || !q
->mem_ops
->get_userptr
||
768 !q
->mem_ops
->put_userptr
)
775 * __verify_mmap_ops() - verify that all memory operations required for
776 * MMAP queue type have been provided
778 static int __verify_mmap_ops(struct vb2_queue
*q
)
780 if (!(q
->io_modes
& VB2_MMAP
) || !q
->mem_ops
->alloc
||
781 !q
->mem_ops
->put
|| !q
->mem_ops
->mmap
)
788 * __verify_dmabuf_ops() - verify that all memory operations required for
789 * DMABUF queue type have been provided
791 static int __verify_dmabuf_ops(struct vb2_queue
*q
)
793 if (!(q
->io_modes
& VB2_DMABUF
) || !q
->mem_ops
->attach_dmabuf
||
794 !q
->mem_ops
->detach_dmabuf
|| !q
->mem_ops
->map_dmabuf
||
795 !q
->mem_ops
->unmap_dmabuf
)
802 * __verify_memory_type() - Check whether the memory type and buffer type
803 * passed to a buffer operation are compatible with the queue.
805 static int __verify_memory_type(struct vb2_queue
*q
,
806 enum v4l2_memory memory
, enum v4l2_buf_type type
)
808 if (memory
!= V4L2_MEMORY_MMAP
&& memory
!= V4L2_MEMORY_USERPTR
&&
809 memory
!= V4L2_MEMORY_DMABUF
) {
810 dprintk(1, "unsupported memory type\n");
814 if (type
!= q
->type
) {
815 dprintk(1, "requested type is incorrect\n");
820 * Make sure all the required memory ops for given memory type
823 if (memory
== V4L2_MEMORY_MMAP
&& __verify_mmap_ops(q
)) {
824 dprintk(1, "MMAP for current setup unsupported\n");
828 if (memory
== V4L2_MEMORY_USERPTR
&& __verify_userptr_ops(q
)) {
829 dprintk(1, "USERPTR for current setup unsupported\n");
833 if (memory
== V4L2_MEMORY_DMABUF
&& __verify_dmabuf_ops(q
)) {
834 dprintk(1, "DMABUF for current setup unsupported\n");
839 * Place the busy tests at the end: -EBUSY can be ignored when
840 * create_bufs is called with count == 0, but count == 0 should still
841 * do the memory and type validation.
843 if (vb2_fileio_is_active(q
)) {
844 dprintk(1, "file io in progress\n");
851 * __reqbufs() - Initiate streaming
852 * @q: videobuf2 queue
853 * @req: struct passed from userspace to vidioc_reqbufs handler in driver
855 * Should be called from vidioc_reqbufs ioctl handler of a driver.
857 * 1) verifies streaming parameters passed from the userspace,
858 * 2) sets up the queue,
859 * 3) negotiates number of buffers and planes per buffer with the driver
860 * to be used during streaming,
861 * 4) allocates internal buffer structures (struct vb2_buffer), according to
862 * the agreed parameters,
863 * 5) for MMAP memory type, allocates actual video memory, using the
864 * memory handling/allocation routines provided during queue initialization
866 * If req->count is 0, all the memory will be freed instead.
867 * If the queue has been allocated previously (by a previous vb2_reqbufs) call
868 * and the queue is not busy, memory will be reallocated.
870 * The return values from this function are intended to be directly returned
871 * from vidioc_reqbufs handler in driver.
873 static int __reqbufs(struct vb2_queue
*q
, struct v4l2_requestbuffers
*req
)
875 unsigned int num_buffers
, allocated_buffers
, num_planes
= 0;
879 dprintk(1, "streaming active\n");
883 if (req
->count
== 0 || q
->num_buffers
!= 0 || q
->memory
!= req
->memory
) {
885 * We already have buffers allocated, so first check if they
886 * are not in use and can be freed.
888 mutex_lock(&q
->mmap_lock
);
889 if (q
->memory
== V4L2_MEMORY_MMAP
&& __buffers_in_use(q
)) {
890 mutex_unlock(&q
->mmap_lock
);
891 dprintk(1, "memory in use, cannot free\n");
896 * Call queue_cancel to clean up any buffers in the PREPARED or
897 * QUEUED state which is possible if buffers were prepared or
898 * queued without ever calling STREAMON.
900 __vb2_queue_cancel(q
);
901 ret
= __vb2_queue_free(q
, q
->num_buffers
);
902 mutex_unlock(&q
->mmap_lock
);
907 * In case of REQBUFS(0) return immediately without calling
908 * driver's queue_setup() callback and allocating resources.
915 * Make sure the requested values and current defaults are sane.
917 num_buffers
= min_t(unsigned int, req
->count
, VIDEO_MAX_FRAME
);
918 num_buffers
= max_t(unsigned int, num_buffers
, q
->min_buffers_needed
);
919 memset(q
->plane_sizes
, 0, sizeof(q
->plane_sizes
));
920 memset(q
->alloc_ctx
, 0, sizeof(q
->alloc_ctx
));
921 q
->memory
= req
->memory
;
924 * Ask the driver how many buffers and planes per buffer it requires.
925 * Driver also sets the size and allocator context for each plane.
927 ret
= call_qop(q
, queue_setup
, q
, NULL
, &num_buffers
, &num_planes
,
928 q
->plane_sizes
, q
->alloc_ctx
);
932 /* Finally, allocate buffers and video memory */
933 allocated_buffers
= __vb2_queue_alloc(q
, req
->memory
, num_buffers
, num_planes
);
934 if (allocated_buffers
== 0) {
935 dprintk(1, "memory allocation failed\n");
940 * There is no point in continuing if we can't allocate the minimum
941 * number of buffers needed by this vb2_queue.
943 if (allocated_buffers
< q
->min_buffers_needed
)
947 * Check if driver can handle the allocated number of buffers.
949 if (!ret
&& allocated_buffers
< num_buffers
) {
950 num_buffers
= allocated_buffers
;
952 ret
= call_qop(q
, queue_setup
, q
, NULL
, &num_buffers
,
953 &num_planes
, q
->plane_sizes
, q
->alloc_ctx
);
955 if (!ret
&& allocated_buffers
< num_buffers
)
959 * Either the driver has accepted a smaller number of buffers,
960 * or .queue_setup() returned an error
964 mutex_lock(&q
->mmap_lock
);
965 q
->num_buffers
= allocated_buffers
;
969 * Note: __vb2_queue_free() will subtract 'allocated_buffers'
970 * from q->num_buffers.
972 __vb2_queue_free(q
, allocated_buffers
);
973 mutex_unlock(&q
->mmap_lock
);
976 mutex_unlock(&q
->mmap_lock
);
979 * Return the number of successfully allocated buffers
982 req
->count
= allocated_buffers
;
983 q
->waiting_for_buffers
= !V4L2_TYPE_IS_OUTPUT(q
->type
);
989 * vb2_reqbufs() - Wrapper for __reqbufs() that also verifies the memory and
991 * @q: videobuf2 queue
992 * @req: struct passed from userspace to vidioc_reqbufs handler in driver
994 int vb2_reqbufs(struct vb2_queue
*q
, struct v4l2_requestbuffers
*req
)
996 int ret
= __verify_memory_type(q
, req
->memory
, req
->type
);
998 return ret
? ret
: __reqbufs(q
, req
);
1000 EXPORT_SYMBOL_GPL(vb2_reqbufs
);
1003 * __create_bufs() - Allocate buffers and any required auxiliary structs
1004 * @q: videobuf2 queue
1005 * @create: creation parameters, passed from userspace to vidioc_create_bufs
1008 * Should be called from vidioc_create_bufs ioctl handler of a driver.
1010 * 1) verifies parameter sanity
1011 * 2) calls the .queue_setup() queue operation
1012 * 3) performs any necessary memory allocations
1014 * The return values from this function are intended to be directly returned
1015 * from vidioc_create_bufs handler in driver.
1017 static int __create_bufs(struct vb2_queue
*q
, struct v4l2_create_buffers
*create
)
1019 unsigned int num_planes
= 0, num_buffers
, allocated_buffers
;
1022 if (q
->num_buffers
== VIDEO_MAX_FRAME
) {
1023 dprintk(1, "maximum number of buffers already allocated\n");
1027 if (!q
->num_buffers
) {
1028 memset(q
->plane_sizes
, 0, sizeof(q
->plane_sizes
));
1029 memset(q
->alloc_ctx
, 0, sizeof(q
->alloc_ctx
));
1030 q
->memory
= create
->memory
;
1031 q
->waiting_for_buffers
= !V4L2_TYPE_IS_OUTPUT(q
->type
);
1034 num_buffers
= min(create
->count
, VIDEO_MAX_FRAME
- q
->num_buffers
);
1037 * Ask the driver, whether the requested number of buffers, planes per
1038 * buffer and their sizes are acceptable
1040 ret
= call_qop(q
, queue_setup
, q
, &create
->format
, &num_buffers
,
1041 &num_planes
, q
->plane_sizes
, q
->alloc_ctx
);
1045 /* Finally, allocate buffers and video memory */
1046 allocated_buffers
= __vb2_queue_alloc(q
, create
->memory
, num_buffers
,
1048 if (allocated_buffers
== 0) {
1049 dprintk(1, "memory allocation failed\n");
1054 * Check if driver can handle the so far allocated number of buffers.
1056 if (allocated_buffers
< num_buffers
) {
1057 num_buffers
= allocated_buffers
;
1060 * q->num_buffers contains the total number of buffers, that the
1061 * queue driver has set up
1063 ret
= call_qop(q
, queue_setup
, q
, &create
->format
, &num_buffers
,
1064 &num_planes
, q
->plane_sizes
, q
->alloc_ctx
);
1066 if (!ret
&& allocated_buffers
< num_buffers
)
1070 * Either the driver has accepted a smaller number of buffers,
1071 * or .queue_setup() returned an error
1075 mutex_lock(&q
->mmap_lock
);
1076 q
->num_buffers
+= allocated_buffers
;
1080 * Note: __vb2_queue_free() will subtract 'allocated_buffers'
1081 * from q->num_buffers.
1083 __vb2_queue_free(q
, allocated_buffers
);
1084 mutex_unlock(&q
->mmap_lock
);
1087 mutex_unlock(&q
->mmap_lock
);
1090 * Return the number of successfully allocated buffers
1093 create
->count
= allocated_buffers
;
1099 * vb2_create_bufs() - Wrapper for __create_bufs() that also verifies the
1100 * memory and type values.
1101 * @q: videobuf2 queue
1102 * @create: creation parameters, passed from userspace to vidioc_create_bufs
1105 int vb2_create_bufs(struct vb2_queue
*q
, struct v4l2_create_buffers
*create
)
1107 int ret
= __verify_memory_type(q
, create
->memory
, create
->format
.type
);
1109 create
->index
= q
->num_buffers
;
1110 if (create
->count
== 0)
1111 return ret
!= -EBUSY
? ret
: 0;
1112 return ret
? ret
: __create_bufs(q
, create
);
1114 EXPORT_SYMBOL_GPL(vb2_create_bufs
);
1117 * vb2_plane_vaddr() - Return a kernel virtual address of a given plane
1118 * @vb: vb2_buffer to which the plane in question belongs to
1119 * @plane_no: plane number for which the address is to be returned
1121 * This function returns a kernel virtual address of a given plane if
1122 * such a mapping exist, NULL otherwise.
1124 void *vb2_plane_vaddr(struct vb2_buffer
*vb
, unsigned int plane_no
)
1126 if (plane_no
> vb
->num_planes
|| !vb
->planes
[plane_no
].mem_priv
)
1129 return call_ptr_memop(vb
, vaddr
, vb
->planes
[plane_no
].mem_priv
);
1132 EXPORT_SYMBOL_GPL(vb2_plane_vaddr
);
1135 * vb2_plane_cookie() - Return allocator specific cookie for the given plane
1136 * @vb: vb2_buffer to which the plane in question belongs to
1137 * @plane_no: plane number for which the cookie is to be returned
1139 * This function returns an allocator specific cookie for a given plane if
1140 * available, NULL otherwise. The allocator should provide some simple static
1141 * inline function, which would convert this cookie to the allocator specific
1142 * type that can be used directly by the driver to access the buffer. This can
1143 * be for example physical address, pointer to scatter list or IOMMU mapping.
1145 void *vb2_plane_cookie(struct vb2_buffer
*vb
, unsigned int plane_no
)
1147 if (plane_no
>= vb
->num_planes
|| !vb
->planes
[plane_no
].mem_priv
)
1150 return call_ptr_memop(vb
, cookie
, vb
->planes
[plane_no
].mem_priv
);
1152 EXPORT_SYMBOL_GPL(vb2_plane_cookie
);
1155 * vb2_buffer_done() - inform videobuf that an operation on a buffer is finished
1156 * @vb: vb2_buffer returned from the driver
1157 * @state: either VB2_BUF_STATE_DONE if the operation finished successfully,
1158 * VB2_BUF_STATE_ERROR if the operation finished with an error or
1159 * VB2_BUF_STATE_QUEUED if the driver wants to requeue buffers.
1160 * If start_streaming fails then it should return buffers with state
1161 * VB2_BUF_STATE_QUEUED to put them back into the queue.
1163 * This function should be called by the driver after a hardware operation on
1164 * a buffer is finished and the buffer may be returned to userspace. The driver
1165 * cannot use this buffer anymore until it is queued back to it by videobuf
1166 * by the means of buf_queue callback. Only buffers previously queued to the
1167 * driver by buf_queue can be passed to this function.
1169 * While streaming a buffer can only be returned in state DONE or ERROR.
1170 * The start_streaming op can also return them in case the DMA engine cannot
1171 * be started for some reason. In that case the buffers should be returned with
1174 void vb2_buffer_done(struct vb2_buffer
*vb
, enum vb2_buffer_state state
)
1176 struct vb2_queue
*q
= vb
->vb2_queue
;
1177 unsigned long flags
;
1180 if (WARN_ON(vb
->state
!= VB2_BUF_STATE_ACTIVE
))
1183 if (WARN_ON(state
!= VB2_BUF_STATE_DONE
&&
1184 state
!= VB2_BUF_STATE_ERROR
&&
1185 state
!= VB2_BUF_STATE_QUEUED
))
1186 state
= VB2_BUF_STATE_ERROR
;
1188 #ifdef CONFIG_VIDEO_ADV_DEBUG
1190 * Although this is not a callback, it still does have to balance
1191 * with the buf_queue op. So update this counter manually.
1195 dprintk(4, "done processing on buffer %d, state: %d\n",
1196 vb
->v4l2_buf
.index
, state
);
1199 for (plane
= 0; plane
< vb
->num_planes
; ++plane
)
1200 call_void_memop(vb
, finish
, vb
->planes
[plane
].mem_priv
);
1202 /* Add the buffer to the done buffers list */
1203 spin_lock_irqsave(&q
->done_lock
, flags
);
1205 if (state
!= VB2_BUF_STATE_QUEUED
)
1206 list_add_tail(&vb
->done_entry
, &q
->done_list
);
1207 atomic_dec(&q
->owned_by_drv_count
);
1208 spin_unlock_irqrestore(&q
->done_lock
, flags
);
1210 if (state
== VB2_BUF_STATE_QUEUED
) {
1211 if (q
->start_streaming_called
)
1212 __enqueue_in_driver(vb
);
1216 /* Inform any processes that may be waiting for buffers */
1217 wake_up(&q
->done_wq
);
1219 EXPORT_SYMBOL_GPL(vb2_buffer_done
);
1222 * vb2_discard_done() - discard all buffers marked as DONE
1223 * @q: videobuf2 queue
1225 * This function is intended to be used with suspend/resume operations. It
1226 * discards all 'done' buffers as they would be too old to be requested after
1229 * Drivers must stop the hardware and synchronize with interrupt handlers and/or
1230 * delayed works before calling this function to make sure no buffer will be
1231 * touched by the driver and/or hardware.
1233 void vb2_discard_done(struct vb2_queue
*q
)
1235 struct vb2_buffer
*vb
;
1236 unsigned long flags
;
1238 spin_lock_irqsave(&q
->done_lock
, flags
);
1239 list_for_each_entry(vb
, &q
->done_list
, done_entry
)
1240 vb
->state
= VB2_BUF_STATE_ERROR
;
1241 spin_unlock_irqrestore(&q
->done_lock
, flags
);
1243 EXPORT_SYMBOL_GPL(vb2_discard_done
);
1246 * __fill_vb2_buffer() - fill a vb2_buffer with information provided in a
1247 * v4l2_buffer by the userspace. The caller has already verified that struct
1248 * v4l2_buffer has a valid number of planes.
1250 static void __fill_vb2_buffer(struct vb2_buffer
*vb
, const struct v4l2_buffer
*b
,
1251 struct v4l2_plane
*v4l2_planes
)
1255 if (V4L2_TYPE_IS_OUTPUT(b
->type
)) {
1256 if (WARN_ON_ONCE(b
->bytesused
== 0)) {
1257 pr_warn_once("use of bytesused == 0 is deprecated and will be removed in the future,\n");
1258 if (vb
->vb2_queue
->allow_zero_bytesused
)
1259 pr_warn_once("use VIDIOC_DECODER_CMD(V4L2_DEC_CMD_STOP) instead.\n");
1261 pr_warn_once("use the actual size instead.\n");
1265 if (V4L2_TYPE_IS_MULTIPLANAR(b
->type
)) {
1266 if (b
->memory
== V4L2_MEMORY_USERPTR
) {
1267 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1268 v4l2_planes
[plane
].m
.userptr
=
1269 b
->m
.planes
[plane
].m
.userptr
;
1270 v4l2_planes
[plane
].length
=
1271 b
->m
.planes
[plane
].length
;
1274 if (b
->memory
== V4L2_MEMORY_DMABUF
) {
1275 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1276 v4l2_planes
[plane
].m
.fd
=
1277 b
->m
.planes
[plane
].m
.fd
;
1278 v4l2_planes
[plane
].length
=
1279 b
->m
.planes
[plane
].length
;
1283 /* Fill in driver-provided information for OUTPUT types */
1284 if (V4L2_TYPE_IS_OUTPUT(b
->type
)) {
1286 * Will have to go up to b->length when API starts
1287 * accepting variable number of planes.
1289 * If bytesused == 0 for the output buffer, then fall
1290 * back to the full buffer size. In that case
1291 * userspace clearly never bothered to set it and
1292 * it's a safe assumption that they really meant to
1293 * use the full plane sizes.
1295 * Some drivers, e.g. old codec drivers, use bytesused == 0
1296 * as a way to indicate that streaming is finished.
1297 * In that case, the driver should use the
1298 * allow_zero_bytesused flag to keep old userspace
1299 * applications working.
1301 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1302 struct v4l2_plane
*pdst
= &v4l2_planes
[plane
];
1303 struct v4l2_plane
*psrc
= &b
->m
.planes
[plane
];
1305 if (vb
->vb2_queue
->allow_zero_bytesused
)
1306 pdst
->bytesused
= psrc
->bytesused
;
1308 pdst
->bytesused
= psrc
->bytesused
?
1309 psrc
->bytesused
: pdst
->length
;
1310 pdst
->data_offset
= psrc
->data_offset
;
1315 * Single-planar buffers do not use planes array,
1316 * so fill in relevant v4l2_buffer struct fields instead.
1317 * In videobuf we use our internal V4l2_planes struct for
1318 * single-planar buffers as well, for simplicity.
1320 * If bytesused == 0 for the output buffer, then fall back
1321 * to the full buffer size as that's a sensible default.
1323 * Some drivers, e.g. old codec drivers, use bytesused == 0 as
1324 * a way to indicate that streaming is finished. In that case,
1325 * the driver should use the allow_zero_bytesused flag to keep
1326 * old userspace applications working.
1328 if (b
->memory
== V4L2_MEMORY_USERPTR
) {
1329 v4l2_planes
[0].m
.userptr
= b
->m
.userptr
;
1330 v4l2_planes
[0].length
= b
->length
;
1333 if (b
->memory
== V4L2_MEMORY_DMABUF
) {
1334 v4l2_planes
[0].m
.fd
= b
->m
.fd
;
1335 v4l2_planes
[0].length
= b
->length
;
1338 if (V4L2_TYPE_IS_OUTPUT(b
->type
)) {
1339 if (vb
->vb2_queue
->allow_zero_bytesused
)
1340 v4l2_planes
[0].bytesused
= b
->bytesused
;
1342 v4l2_planes
[0].bytesused
= b
->bytesused
?
1343 b
->bytesused
: v4l2_planes
[0].length
;
1345 v4l2_planes
[0].bytesused
= 0;
1349 /* Zero flags that the vb2 core handles */
1350 vb
->v4l2_buf
.flags
= b
->flags
& ~V4L2_BUFFER_MASK_FLAGS
;
1351 if ((vb
->vb2_queue
->timestamp_flags
& V4L2_BUF_FLAG_TIMESTAMP_MASK
) !=
1352 V4L2_BUF_FLAG_TIMESTAMP_COPY
|| !V4L2_TYPE_IS_OUTPUT(b
->type
)) {
1354 * Non-COPY timestamps and non-OUTPUT queues will get
1355 * their timestamp and timestamp source flags from the
1358 vb
->v4l2_buf
.flags
&= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK
;
1361 if (V4L2_TYPE_IS_OUTPUT(b
->type
)) {
1363 * For output buffers mask out the timecode flag:
1364 * this will be handled later in vb2_internal_qbuf().
1365 * The 'field' is valid metadata for this output buffer
1366 * and so that needs to be copied here.
1368 vb
->v4l2_buf
.flags
&= ~V4L2_BUF_FLAG_TIMECODE
;
1369 vb
->v4l2_buf
.field
= b
->field
;
1371 /* Zero any output buffer flags as this is a capture buffer */
1372 vb
->v4l2_buf
.flags
&= ~V4L2_BUFFER_OUT_FLAGS
;
1377 * __qbuf_mmap() - handle qbuf of an MMAP buffer
1379 static int __qbuf_mmap(struct vb2_buffer
*vb
, const struct v4l2_buffer
*b
)
1381 __fill_vb2_buffer(vb
, b
, vb
->v4l2_planes
);
1382 return call_vb_qop(vb
, buf_prepare
, vb
);
1386 * __qbuf_userptr() - handle qbuf of a USERPTR buffer
1388 static int __qbuf_userptr(struct vb2_buffer
*vb
, const struct v4l2_buffer
*b
)
1390 struct v4l2_plane planes
[VIDEO_MAX_PLANES
];
1391 struct vb2_queue
*q
= vb
->vb2_queue
;
1395 enum dma_data_direction dma_dir
=
1396 V4L2_TYPE_IS_OUTPUT(q
->type
) ? DMA_TO_DEVICE
: DMA_FROM_DEVICE
;
1397 bool reacquired
= vb
->planes
[0].mem_priv
== NULL
;
1399 memset(planes
, 0, sizeof(planes
[0]) * vb
->num_planes
);
1400 /* Copy relevant information provided by the userspace */
1401 __fill_vb2_buffer(vb
, b
, planes
);
1403 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1404 /* Skip the plane if already verified */
1405 if (vb
->v4l2_planes
[plane
].m
.userptr
&&
1406 vb
->v4l2_planes
[plane
].m
.userptr
== planes
[plane
].m
.userptr
1407 && vb
->v4l2_planes
[plane
].length
== planes
[plane
].length
)
1410 dprintk(3, "userspace address for plane %d changed, "
1411 "reacquiring memory\n", plane
);
1413 /* Check if the provided plane buffer is large enough */
1414 if (planes
[plane
].length
< q
->plane_sizes
[plane
]) {
1415 dprintk(1, "provided buffer size %u is less than "
1416 "setup size %u for plane %d\n",
1417 planes
[plane
].length
,
1418 q
->plane_sizes
[plane
], plane
);
1423 /* Release previously acquired memory if present */
1424 if (vb
->planes
[plane
].mem_priv
) {
1427 call_void_vb_qop(vb
, buf_cleanup
, vb
);
1429 call_void_memop(vb
, put_userptr
, vb
->planes
[plane
].mem_priv
);
1432 vb
->planes
[plane
].mem_priv
= NULL
;
1433 memset(&vb
->v4l2_planes
[plane
], 0, sizeof(struct v4l2_plane
));
1435 /* Acquire each plane's memory */
1436 mem_priv
= call_ptr_memop(vb
, get_userptr
, q
->alloc_ctx
[plane
],
1437 planes
[plane
].m
.userptr
,
1438 planes
[plane
].length
, dma_dir
);
1439 if (IS_ERR_OR_NULL(mem_priv
)) {
1440 dprintk(1, "failed acquiring userspace "
1441 "memory for plane %d\n", plane
);
1442 ret
= mem_priv
? PTR_ERR(mem_priv
) : -EINVAL
;
1445 vb
->planes
[plane
].mem_priv
= mem_priv
;
1449 * Now that everything is in order, copy relevant information
1450 * provided by userspace.
1452 for (plane
= 0; plane
< vb
->num_planes
; ++plane
)
1453 vb
->v4l2_planes
[plane
] = planes
[plane
];
1457 * One or more planes changed, so we must call buf_init to do
1458 * the driver-specific initialization on the newly acquired
1459 * buffer, if provided.
1461 ret
= call_vb_qop(vb
, buf_init
, vb
);
1463 dprintk(1, "buffer initialization failed\n");
1468 ret
= call_vb_qop(vb
, buf_prepare
, vb
);
1470 dprintk(1, "buffer preparation failed\n");
1471 call_void_vb_qop(vb
, buf_cleanup
, vb
);
1477 /* In case of errors, release planes that were already acquired */
1478 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1479 if (vb
->planes
[plane
].mem_priv
)
1480 call_void_memop(vb
, put_userptr
, vb
->planes
[plane
].mem_priv
);
1481 vb
->planes
[plane
].mem_priv
= NULL
;
1482 vb
->v4l2_planes
[plane
].m
.userptr
= 0;
1483 vb
->v4l2_planes
[plane
].length
= 0;
1490 * __qbuf_dmabuf() - handle qbuf of a DMABUF buffer
1492 static int __qbuf_dmabuf(struct vb2_buffer
*vb
, const struct v4l2_buffer
*b
)
1494 struct v4l2_plane planes
[VIDEO_MAX_PLANES
];
1495 struct vb2_queue
*q
= vb
->vb2_queue
;
1499 enum dma_data_direction dma_dir
=
1500 V4L2_TYPE_IS_OUTPUT(q
->type
) ? DMA_TO_DEVICE
: DMA_FROM_DEVICE
;
1501 bool reacquired
= vb
->planes
[0].mem_priv
== NULL
;
1503 memset(planes
, 0, sizeof(planes
[0]) * vb
->num_planes
);
1504 /* Copy relevant information provided by the userspace */
1505 __fill_vb2_buffer(vb
, b
, planes
);
1507 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1508 struct dma_buf
*dbuf
= dma_buf_get(planes
[plane
].m
.fd
);
1510 if (IS_ERR_OR_NULL(dbuf
)) {
1511 dprintk(1, "invalid dmabuf fd for plane %d\n",
1517 /* use DMABUF size if length is not provided */
1518 if (planes
[plane
].length
== 0)
1519 planes
[plane
].length
= dbuf
->size
;
1521 if (planes
[plane
].length
< q
->plane_sizes
[plane
]) {
1522 dprintk(1, "invalid dmabuf length for plane %d\n",
1528 /* Skip the plane if already verified */
1529 if (dbuf
== vb
->planes
[plane
].dbuf
&&
1530 vb
->v4l2_planes
[plane
].length
== planes
[plane
].length
) {
1535 dprintk(1, "buffer for plane %d changed\n", plane
);
1539 call_void_vb_qop(vb
, buf_cleanup
, vb
);
1542 /* Release previously acquired memory if present */
1543 __vb2_plane_dmabuf_put(vb
, &vb
->planes
[plane
]);
1544 memset(&vb
->v4l2_planes
[plane
], 0, sizeof(struct v4l2_plane
));
1546 /* Acquire each plane's memory */
1547 mem_priv
= call_ptr_memop(vb
, attach_dmabuf
, q
->alloc_ctx
[plane
],
1548 dbuf
, planes
[plane
].length
, dma_dir
);
1549 if (IS_ERR(mem_priv
)) {
1550 dprintk(1, "failed to attach dmabuf\n");
1551 ret
= PTR_ERR(mem_priv
);
1556 vb
->planes
[plane
].dbuf
= dbuf
;
1557 vb
->planes
[plane
].mem_priv
= mem_priv
;
1560 /* TODO: This pins the buffer(s) with dma_buf_map_attachment()).. but
1561 * really we want to do this just before the DMA, not while queueing
1564 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1565 ret
= call_memop(vb
, map_dmabuf
, vb
->planes
[plane
].mem_priv
);
1567 dprintk(1, "failed to map dmabuf for plane %d\n",
1571 vb
->planes
[plane
].dbuf_mapped
= 1;
1575 * Now that everything is in order, copy relevant information
1576 * provided by userspace.
1578 for (plane
= 0; plane
< vb
->num_planes
; ++plane
)
1579 vb
->v4l2_planes
[plane
] = planes
[plane
];
1583 * Call driver-specific initialization on the newly acquired buffer,
1586 ret
= call_vb_qop(vb
, buf_init
, vb
);
1588 dprintk(1, "buffer initialization failed\n");
1593 ret
= call_vb_qop(vb
, buf_prepare
, vb
);
1595 dprintk(1, "buffer preparation failed\n");
1596 call_void_vb_qop(vb
, buf_cleanup
, vb
);
1602 /* In case of errors, release planes that were already acquired */
1603 __vb2_buf_dmabuf_put(vb
);
1609 * __enqueue_in_driver() - enqueue a vb2_buffer in driver for processing
1611 static void __enqueue_in_driver(struct vb2_buffer
*vb
)
1613 struct vb2_queue
*q
= vb
->vb2_queue
;
1616 vb
->state
= VB2_BUF_STATE_ACTIVE
;
1617 atomic_inc(&q
->owned_by_drv_count
);
1620 for (plane
= 0; plane
< vb
->num_planes
; ++plane
)
1621 call_void_memop(vb
, prepare
, vb
->planes
[plane
].mem_priv
);
1623 call_void_vb_qop(vb
, buf_queue
, vb
);
1626 static int __buf_prepare(struct vb2_buffer
*vb
, const struct v4l2_buffer
*b
)
1628 struct vb2_queue
*q
= vb
->vb2_queue
;
1631 ret
= __verify_length(vb
, b
);
1633 dprintk(1, "plane parameters verification failed: %d\n", ret
);
1636 if (b
->field
== V4L2_FIELD_ALTERNATE
&& V4L2_TYPE_IS_OUTPUT(q
->type
)) {
1638 * If the format's field is ALTERNATE, then the buffer's field
1639 * should be either TOP or BOTTOM, not ALTERNATE since that
1640 * makes no sense. The driver has to know whether the
1641 * buffer represents a top or a bottom field in order to
1642 * program any DMA correctly. Using ALTERNATE is wrong, since
1643 * that just says that it is either a top or a bottom field,
1644 * but not which of the two it is.
1646 dprintk(1, "the field is incorrectly set to ALTERNATE for an output buffer\n");
1651 dprintk(1, "fatal error occurred on queue\n");
1655 vb
->state
= VB2_BUF_STATE_PREPARING
;
1656 vb
->v4l2_buf
.timestamp
.tv_sec
= 0;
1657 vb
->v4l2_buf
.timestamp
.tv_usec
= 0;
1658 vb
->v4l2_buf
.sequence
= 0;
1660 switch (q
->memory
) {
1661 case V4L2_MEMORY_MMAP
:
1662 ret
= __qbuf_mmap(vb
, b
);
1664 case V4L2_MEMORY_USERPTR
:
1665 ret
= __qbuf_userptr(vb
, b
);
1667 case V4L2_MEMORY_DMABUF
:
1668 ret
= __qbuf_dmabuf(vb
, b
);
1671 WARN(1, "Invalid queue type\n");
1676 dprintk(1, "buffer preparation failed: %d\n", ret
);
1677 vb
->state
= ret
? VB2_BUF_STATE_DEQUEUED
: VB2_BUF_STATE_PREPARED
;
1682 static int vb2_queue_or_prepare_buf(struct vb2_queue
*q
, struct v4l2_buffer
*b
,
1685 if (b
->type
!= q
->type
) {
1686 dprintk(1, "%s: invalid buffer type\n", opname
);
1690 if (b
->index
>= q
->num_buffers
) {
1691 dprintk(1, "%s: buffer index out of range\n", opname
);
1695 if (q
->bufs
[b
->index
] == NULL
) {
1696 /* Should never happen */
1697 dprintk(1, "%s: buffer is NULL\n", opname
);
1701 if (b
->memory
!= q
->memory
) {
1702 dprintk(1, "%s: invalid memory type\n", opname
);
1706 return __verify_planes_array(q
->bufs
[b
->index
], b
);
1710 * vb2_prepare_buf() - Pass ownership of a buffer from userspace to the kernel
1711 * @q: videobuf2 queue
1712 * @b: buffer structure passed from userspace to vidioc_prepare_buf
1715 * Should be called from vidioc_prepare_buf ioctl handler of a driver.
1717 * 1) verifies the passed buffer,
1718 * 2) calls buf_prepare callback in the driver (if provided), in which
1719 * driver-specific buffer initialization can be performed,
1721 * The return values from this function are intended to be directly returned
1722 * from vidioc_prepare_buf handler in driver.
1724 int vb2_prepare_buf(struct vb2_queue
*q
, struct v4l2_buffer
*b
)
1726 struct vb2_buffer
*vb
;
1729 if (vb2_fileio_is_active(q
)) {
1730 dprintk(1, "file io in progress\n");
1734 ret
= vb2_queue_or_prepare_buf(q
, b
, "prepare_buf");
1738 vb
= q
->bufs
[b
->index
];
1739 if (vb
->state
!= VB2_BUF_STATE_DEQUEUED
) {
1740 dprintk(1, "invalid buffer state %d\n",
1745 ret
= __buf_prepare(vb
, b
);
1747 /* Fill buffer information for the userspace */
1748 __fill_v4l2_buffer(vb
, b
);
1750 dprintk(1, "prepare of buffer %d succeeded\n", vb
->v4l2_buf
.index
);
1754 EXPORT_SYMBOL_GPL(vb2_prepare_buf
);
1757 * vb2_start_streaming() - Attempt to start streaming.
1758 * @q: videobuf2 queue
1760 * Attempt to start streaming. When this function is called there must be
1761 * at least q->min_buffers_needed buffers queued up (i.e. the minimum
1762 * number of buffers required for the DMA engine to function). If the
1763 * @start_streaming op fails it is supposed to return all the driver-owned
1764 * buffers back to vb2 in state QUEUED. Check if that happened and if
1765 * not warn and reclaim them forcefully.
1767 static int vb2_start_streaming(struct vb2_queue
*q
)
1769 struct vb2_buffer
*vb
;
1773 * If any buffers were queued before streamon,
1774 * we can now pass them to driver for processing.
1776 list_for_each_entry(vb
, &q
->queued_list
, queued_entry
)
1777 __enqueue_in_driver(vb
);
1779 /* Tell the driver to start streaming */
1780 q
->start_streaming_called
= 1;
1781 ret
= call_qop(q
, start_streaming
, q
,
1782 atomic_read(&q
->owned_by_drv_count
));
1786 q
->start_streaming_called
= 0;
1788 dprintk(1, "driver refused to start streaming\n");
1790 * If you see this warning, then the driver isn't cleaning up properly
1791 * after a failed start_streaming(). See the start_streaming()
1792 * documentation in videobuf2-core.h for more information how buffers
1793 * should be returned to vb2 in start_streaming().
1795 if (WARN_ON(atomic_read(&q
->owned_by_drv_count
))) {
1799 * Forcefully reclaim buffers if the driver did not
1800 * correctly return them to vb2.
1802 for (i
= 0; i
< q
->num_buffers
; ++i
) {
1804 if (vb
->state
== VB2_BUF_STATE_ACTIVE
)
1805 vb2_buffer_done(vb
, VB2_BUF_STATE_QUEUED
);
1807 /* Must be zero now */
1808 WARN_ON(atomic_read(&q
->owned_by_drv_count
));
1811 * If done_list is not empty, then start_streaming() didn't call
1812 * vb2_buffer_done(vb, VB2_BUF_STATE_QUEUED) but STATE_ERROR or
1815 WARN_ON(!list_empty(&q
->done_list
));
1819 static int vb2_internal_qbuf(struct vb2_queue
*q
, struct v4l2_buffer
*b
)
1821 int ret
= vb2_queue_or_prepare_buf(q
, b
, "qbuf");
1822 struct vb2_buffer
*vb
;
1827 vb
= q
->bufs
[b
->index
];
1829 switch (vb
->state
) {
1830 case VB2_BUF_STATE_DEQUEUED
:
1831 ret
= __buf_prepare(vb
, b
);
1835 case VB2_BUF_STATE_PREPARED
:
1837 case VB2_BUF_STATE_PREPARING
:
1838 dprintk(1, "buffer still being prepared\n");
1841 dprintk(1, "invalid buffer state %d\n", vb
->state
);
1846 * Add to the queued buffers list, a buffer will stay on it until
1847 * dequeued in dqbuf.
1849 list_add_tail(&vb
->queued_entry
, &q
->queued_list
);
1851 q
->waiting_for_buffers
= false;
1852 vb
->state
= VB2_BUF_STATE_QUEUED
;
1853 if (V4L2_TYPE_IS_OUTPUT(q
->type
)) {
1855 * For output buffers copy the timestamp if needed,
1856 * and the timecode field and flag if needed.
1858 if ((q
->timestamp_flags
& V4L2_BUF_FLAG_TIMESTAMP_MASK
) ==
1859 V4L2_BUF_FLAG_TIMESTAMP_COPY
)
1860 vb
->v4l2_buf
.timestamp
= b
->timestamp
;
1861 vb
->v4l2_buf
.flags
|= b
->flags
& V4L2_BUF_FLAG_TIMECODE
;
1862 if (b
->flags
& V4L2_BUF_FLAG_TIMECODE
)
1863 vb
->v4l2_buf
.timecode
= b
->timecode
;
1867 * If already streaming, give the buffer to driver for processing.
1868 * If not, the buffer will be given to driver on next streamon.
1870 if (q
->start_streaming_called
)
1871 __enqueue_in_driver(vb
);
1873 /* Fill buffer information for the userspace */
1874 __fill_v4l2_buffer(vb
, b
);
1877 * If streamon has been called, and we haven't yet called
1878 * start_streaming() since not enough buffers were queued, and
1879 * we now have reached the minimum number of queued buffers,
1880 * then we can finally call start_streaming().
1882 if (q
->streaming
&& !q
->start_streaming_called
&&
1883 q
->queued_count
>= q
->min_buffers_needed
) {
1884 ret
= vb2_start_streaming(q
);
1889 dprintk(1, "qbuf of buffer %d succeeded\n", vb
->v4l2_buf
.index
);
1894 * vb2_qbuf() - Queue a buffer from userspace
1895 * @q: videobuf2 queue
1896 * @b: buffer structure passed from userspace to vidioc_qbuf handler
1899 * Should be called from vidioc_qbuf ioctl handler of a driver.
1901 * 1) verifies the passed buffer,
1902 * 2) if necessary, calls buf_prepare callback in the driver (if provided), in
1903 * which driver-specific buffer initialization can be performed,
1904 * 3) if streaming is on, queues the buffer in driver by the means of buf_queue
1905 * callback for processing.
1907 * The return values from this function are intended to be directly returned
1908 * from vidioc_qbuf handler in driver.
1910 int vb2_qbuf(struct vb2_queue
*q
, struct v4l2_buffer
*b
)
1912 if (vb2_fileio_is_active(q
)) {
1913 dprintk(1, "file io in progress\n");
1917 return vb2_internal_qbuf(q
, b
);
1919 EXPORT_SYMBOL_GPL(vb2_qbuf
);
1922 * __vb2_wait_for_done_vb() - wait for a buffer to become available
1925 * Will sleep if required for nonblocking == false.
1927 static int __vb2_wait_for_done_vb(struct vb2_queue
*q
, int nonblocking
)
1930 * All operations on vb_done_list are performed under done_lock
1931 * spinlock protection. However, buffers may be removed from
1932 * it and returned to userspace only while holding both driver's
1933 * lock and the done_lock spinlock. Thus we can be sure that as
1934 * long as we hold the driver's lock, the list will remain not
1935 * empty if list_empty() check succeeds.
1941 if (!q
->streaming
) {
1942 dprintk(1, "streaming off, will not wait for buffers\n");
1947 dprintk(1, "Queue in error state, will not wait for buffers\n");
1951 if (q
->last_buffer_dequeued
) {
1952 dprintk(3, "last buffer dequeued already, will not wait for buffers\n");
1956 if (!list_empty(&q
->done_list
)) {
1958 * Found a buffer that we were waiting for.
1964 dprintk(1, "nonblocking and no buffers to dequeue, "
1970 * We are streaming and blocking, wait for another buffer to
1971 * become ready or for streamoff. Driver's lock is released to
1972 * allow streamoff or qbuf to be called while waiting.
1974 call_void_qop(q
, wait_prepare
, q
);
1977 * All locks have been released, it is safe to sleep now.
1979 dprintk(3, "will sleep waiting for buffers\n");
1980 ret
= wait_event_interruptible(q
->done_wq
,
1981 !list_empty(&q
->done_list
) || !q
->streaming
||
1985 * We need to reevaluate both conditions again after reacquiring
1986 * the locks or return an error if one occurred.
1988 call_void_qop(q
, wait_finish
, q
);
1990 dprintk(1, "sleep was interrupted\n");
1998 * __vb2_get_done_vb() - get a buffer ready for dequeuing
2000 * Will sleep if required for nonblocking == false.
2002 static int __vb2_get_done_vb(struct vb2_queue
*q
, struct vb2_buffer
**vb
,
2003 struct v4l2_buffer
*b
, int nonblocking
)
2005 unsigned long flags
;
2009 * Wait for at least one buffer to become available on the done_list.
2011 ret
= __vb2_wait_for_done_vb(q
, nonblocking
);
2016 * Driver's lock has been held since we last verified that done_list
2017 * is not empty, so no need for another list_empty(done_list) check.
2019 spin_lock_irqsave(&q
->done_lock
, flags
);
2020 *vb
= list_first_entry(&q
->done_list
, struct vb2_buffer
, done_entry
);
2022 * Only remove the buffer from done_list if v4l2_buffer can handle all
2025 ret
= __verify_planes_array(*vb
, b
);
2027 list_del(&(*vb
)->done_entry
);
2028 spin_unlock_irqrestore(&q
->done_lock
, flags
);
2034 * vb2_wait_for_all_buffers() - wait until all buffers are given back to vb2
2035 * @q: videobuf2 queue
2037 * This function will wait until all buffers that have been given to the driver
2038 * by buf_queue() are given back to vb2 with vb2_buffer_done(). It doesn't call
2039 * wait_prepare, wait_finish pair. It is intended to be called with all locks
2040 * taken, for example from stop_streaming() callback.
2042 int vb2_wait_for_all_buffers(struct vb2_queue
*q
)
2044 if (!q
->streaming
) {
2045 dprintk(1, "streaming off, will not wait for buffers\n");
2049 if (q
->start_streaming_called
)
2050 wait_event(q
->done_wq
, !atomic_read(&q
->owned_by_drv_count
));
2053 EXPORT_SYMBOL_GPL(vb2_wait_for_all_buffers
);
2056 * __vb2_dqbuf() - bring back the buffer to the DEQUEUED state
2058 static void __vb2_dqbuf(struct vb2_buffer
*vb
)
2060 struct vb2_queue
*q
= vb
->vb2_queue
;
2063 /* nothing to do if the buffer is already dequeued */
2064 if (vb
->state
== VB2_BUF_STATE_DEQUEUED
)
2067 vb
->state
= VB2_BUF_STATE_DEQUEUED
;
2069 /* unmap DMABUF buffer */
2070 if (q
->memory
== V4L2_MEMORY_DMABUF
)
2071 for (i
= 0; i
< vb
->num_planes
; ++i
) {
2072 if (!vb
->planes
[i
].dbuf_mapped
)
2074 call_void_memop(vb
, unmap_dmabuf
, vb
->planes
[i
].mem_priv
);
2075 vb
->planes
[i
].dbuf_mapped
= 0;
2079 static int vb2_internal_dqbuf(struct vb2_queue
*q
, struct v4l2_buffer
*b
, bool nonblocking
)
2081 struct vb2_buffer
*vb
= NULL
;
2084 if (b
->type
!= q
->type
) {
2085 dprintk(1, "invalid buffer type\n");
2088 ret
= __vb2_get_done_vb(q
, &vb
, b
, nonblocking
);
2092 switch (vb
->state
) {
2093 case VB2_BUF_STATE_DONE
:
2094 dprintk(3, "returning done buffer\n");
2096 case VB2_BUF_STATE_ERROR
:
2097 dprintk(3, "returning done buffer with errors\n");
2100 dprintk(1, "invalid buffer state\n");
2104 call_void_vb_qop(vb
, buf_finish
, vb
);
2106 /* Fill buffer information for the userspace */
2107 __fill_v4l2_buffer(vb
, b
);
2108 /* Remove from videobuf queue */
2109 list_del(&vb
->queued_entry
);
2111 if (!V4L2_TYPE_IS_OUTPUT(q
->type
) &&
2112 vb
->v4l2_buf
.flags
& V4L2_BUF_FLAG_LAST
)
2113 q
->last_buffer_dequeued
= true;
2114 /* go back to dequeued state */
2117 dprintk(1, "dqbuf of buffer %d, with state %d\n",
2118 vb
->v4l2_buf
.index
, vb
->state
);
2124 * vb2_dqbuf() - Dequeue a buffer to the userspace
2125 * @q: videobuf2 queue
2126 * @b: buffer structure passed from userspace to vidioc_dqbuf handler
2128 * @nonblocking: if true, this call will not sleep waiting for a buffer if no
2129 * buffers ready for dequeuing are present. Normally the driver
2130 * would be passing (file->f_flags & O_NONBLOCK) here
2132 * Should be called from vidioc_dqbuf ioctl handler of a driver.
2134 * 1) verifies the passed buffer,
2135 * 2) calls buf_finish callback in the driver (if provided), in which
2136 * driver can perform any additional operations that may be required before
2137 * returning the buffer to userspace, such as cache sync,
2138 * 3) the buffer struct members are filled with relevant information for
2141 * The return values from this function are intended to be directly returned
2142 * from vidioc_dqbuf handler in driver.
2144 int vb2_dqbuf(struct vb2_queue
*q
, struct v4l2_buffer
*b
, bool nonblocking
)
2146 if (vb2_fileio_is_active(q
)) {
2147 dprintk(1, "file io in progress\n");
2150 return vb2_internal_dqbuf(q
, b
, nonblocking
);
2152 EXPORT_SYMBOL_GPL(vb2_dqbuf
);
2155 * __vb2_queue_cancel() - cancel and stop (pause) streaming
2157 * Removes all queued buffers from driver's queue and all buffers queued by
2158 * userspace from videobuf's queue. Returns to state after reqbufs.
2160 static void __vb2_queue_cancel(struct vb2_queue
*q
)
2165 * Tell driver to stop all transactions and release all queued
2168 if (q
->start_streaming_called
)
2169 call_void_qop(q
, stop_streaming
, q
);
2172 * If you see this warning, then the driver isn't cleaning up properly
2173 * in stop_streaming(). See the stop_streaming() documentation in
2174 * videobuf2-core.h for more information how buffers should be returned
2175 * to vb2 in stop_streaming().
2177 if (WARN_ON(atomic_read(&q
->owned_by_drv_count
))) {
2178 for (i
= 0; i
< q
->num_buffers
; ++i
)
2179 if (q
->bufs
[i
]->state
== VB2_BUF_STATE_ACTIVE
)
2180 vb2_buffer_done(q
->bufs
[i
], VB2_BUF_STATE_ERROR
);
2181 /* Must be zero now */
2182 WARN_ON(atomic_read(&q
->owned_by_drv_count
));
2186 q
->start_streaming_called
= 0;
2187 q
->queued_count
= 0;
2191 * Remove all buffers from videobuf's list...
2193 INIT_LIST_HEAD(&q
->queued_list
);
2195 * ...and done list; userspace will not receive any buffers it
2196 * has not already dequeued before initiating cancel.
2198 INIT_LIST_HEAD(&q
->done_list
);
2199 atomic_set(&q
->owned_by_drv_count
, 0);
2200 wake_up_all(&q
->done_wq
);
2203 * Reinitialize all buffers for next use.
2204 * Make sure to call buf_finish for any queued buffers. Normally
2205 * that's done in dqbuf, but that's not going to happen when we
2206 * cancel the whole queue. Note: this code belongs here, not in
2207 * __vb2_dqbuf() since in vb2_internal_dqbuf() there is a critical
2208 * call to __fill_v4l2_buffer() after buf_finish(). That order can't
2209 * be changed, so we can't move the buf_finish() to __vb2_dqbuf().
2211 for (i
= 0; i
< q
->num_buffers
; ++i
) {
2212 struct vb2_buffer
*vb
= q
->bufs
[i
];
2214 if (vb
->state
!= VB2_BUF_STATE_DEQUEUED
) {
2215 vb
->state
= VB2_BUF_STATE_PREPARED
;
2216 call_void_vb_qop(vb
, buf_finish
, vb
);
2222 static int vb2_internal_streamon(struct vb2_queue
*q
, enum v4l2_buf_type type
)
2226 if (type
!= q
->type
) {
2227 dprintk(1, "invalid stream type\n");
2232 dprintk(3, "already streaming\n");
2236 if (!q
->num_buffers
) {
2237 dprintk(1, "no buffers have been allocated\n");
2241 if (q
->num_buffers
< q
->min_buffers_needed
) {
2242 dprintk(1, "need at least %u allocated buffers\n",
2243 q
->min_buffers_needed
);
2248 * Tell driver to start streaming provided sufficient buffers
2251 if (q
->queued_count
>= q
->min_buffers_needed
) {
2252 ret
= vb2_start_streaming(q
);
2254 __vb2_queue_cancel(q
);
2261 dprintk(3, "successful\n");
2266 * vb2_queue_error() - signal a fatal error on the queue
2267 * @q: videobuf2 queue
2269 * Flag that a fatal unrecoverable error has occurred and wake up all processes
2270 * waiting on the queue. Polling will now set POLLERR and queuing and dequeuing
2271 * buffers will return -EIO.
2273 * The error flag will be cleared when cancelling the queue, either from
2274 * vb2_streamoff or vb2_queue_release. Drivers should thus not call this
2275 * function before starting the stream, otherwise the error flag will remain set
2276 * until the queue is released when closing the device node.
2278 void vb2_queue_error(struct vb2_queue
*q
)
2282 wake_up_all(&q
->done_wq
);
2284 EXPORT_SYMBOL_GPL(vb2_queue_error
);
2287 * vb2_streamon - start streaming
2288 * @q: videobuf2 queue
2289 * @type: type argument passed from userspace to vidioc_streamon handler
2291 * Should be called from vidioc_streamon handler of a driver.
2293 * 1) verifies current state
2294 * 2) passes any previously queued buffers to the driver and starts streaming
2296 * The return values from this function are intended to be directly returned
2297 * from vidioc_streamon handler in the driver.
2299 int vb2_streamon(struct vb2_queue
*q
, enum v4l2_buf_type type
)
2301 if (vb2_fileio_is_active(q
)) {
2302 dprintk(1, "file io in progress\n");
2305 return vb2_internal_streamon(q
, type
);
2307 EXPORT_SYMBOL_GPL(vb2_streamon
);
2309 static int vb2_internal_streamoff(struct vb2_queue
*q
, enum v4l2_buf_type type
)
2311 if (type
!= q
->type
) {
2312 dprintk(1, "invalid stream type\n");
2317 * Cancel will pause streaming and remove all buffers from the driver
2318 * and videobuf, effectively returning control over them to userspace.
2320 * Note that we do this even if q->streaming == 0: if you prepare or
2321 * queue buffers, and then call streamoff without ever having called
2322 * streamon, you would still expect those buffers to be returned to
2323 * their normal dequeued state.
2325 __vb2_queue_cancel(q
);
2326 q
->waiting_for_buffers
= !V4L2_TYPE_IS_OUTPUT(q
->type
);
2327 q
->last_buffer_dequeued
= false;
2329 dprintk(3, "successful\n");
2334 * vb2_streamoff - stop streaming
2335 * @q: videobuf2 queue
2336 * @type: type argument passed from userspace to vidioc_streamoff handler
2338 * Should be called from vidioc_streamoff handler of a driver.
2340 * 1) verifies current state,
2341 * 2) stop streaming and dequeues any queued buffers, including those previously
2342 * passed to the driver (after waiting for the driver to finish).
2344 * This call can be used for pausing playback.
2345 * The return values from this function are intended to be directly returned
2346 * from vidioc_streamoff handler in the driver
2348 int vb2_streamoff(struct vb2_queue
*q
, enum v4l2_buf_type type
)
2350 if (vb2_fileio_is_active(q
)) {
2351 dprintk(1, "file io in progress\n");
2354 return vb2_internal_streamoff(q
, type
);
2356 EXPORT_SYMBOL_GPL(vb2_streamoff
);
2359 * __find_plane_by_offset() - find plane associated with the given offset off
2361 static int __find_plane_by_offset(struct vb2_queue
*q
, unsigned long off
,
2362 unsigned int *_buffer
, unsigned int *_plane
)
2364 struct vb2_buffer
*vb
;
2365 unsigned int buffer
, plane
;
2368 * Go over all buffers and their planes, comparing the given offset
2369 * with an offset assigned to each plane. If a match is found,
2370 * return its buffer and plane numbers.
2372 for (buffer
= 0; buffer
< q
->num_buffers
; ++buffer
) {
2373 vb
= q
->bufs
[buffer
];
2375 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
2376 if (vb
->v4l2_planes
[plane
].m
.mem_offset
== off
) {
2388 * vb2_expbuf() - Export a buffer as a file descriptor
2389 * @q: videobuf2 queue
2390 * @eb: export buffer structure passed from userspace to vidioc_expbuf
2393 * The return values from this function are intended to be directly returned
2394 * from vidioc_expbuf handler in driver.
2396 int vb2_expbuf(struct vb2_queue
*q
, struct v4l2_exportbuffer
*eb
)
2398 struct vb2_buffer
*vb
= NULL
;
2399 struct vb2_plane
*vb_plane
;
2401 struct dma_buf
*dbuf
;
2403 if (q
->memory
!= V4L2_MEMORY_MMAP
) {
2404 dprintk(1, "queue is not currently set up for mmap\n");
2408 if (!q
->mem_ops
->get_dmabuf
) {
2409 dprintk(1, "queue does not support DMA buffer exporting\n");
2413 if (eb
->flags
& ~(O_CLOEXEC
| O_ACCMODE
)) {
2414 dprintk(1, "queue does support only O_CLOEXEC and access mode flags\n");
2418 if (eb
->type
!= q
->type
) {
2419 dprintk(1, "invalid buffer type\n");
2423 if (eb
->index
>= q
->num_buffers
) {
2424 dprintk(1, "buffer index out of range\n");
2428 vb
= q
->bufs
[eb
->index
];
2430 if (eb
->plane
>= vb
->num_planes
) {
2431 dprintk(1, "buffer plane out of range\n");
2435 if (vb2_fileio_is_active(q
)) {
2436 dprintk(1, "expbuf: file io in progress\n");
2440 vb_plane
= &vb
->planes
[eb
->plane
];
2442 dbuf
= call_ptr_memop(vb
, get_dmabuf
, vb_plane
->mem_priv
, eb
->flags
& O_ACCMODE
);
2443 if (IS_ERR_OR_NULL(dbuf
)) {
2444 dprintk(1, "failed to export buffer %d, plane %d\n",
2445 eb
->index
, eb
->plane
);
2449 ret
= dma_buf_fd(dbuf
, eb
->flags
& ~O_ACCMODE
);
2451 dprintk(3, "buffer %d, plane %d failed to export (%d)\n",
2452 eb
->index
, eb
->plane
, ret
);
2457 dprintk(3, "buffer %d, plane %d exported as %d descriptor\n",
2458 eb
->index
, eb
->plane
, ret
);
2463 EXPORT_SYMBOL_GPL(vb2_expbuf
);
2466 * vb2_mmap() - map video buffers into application address space
2467 * @q: videobuf2 queue
2468 * @vma: vma passed to the mmap file operation handler in the driver
2470 * Should be called from mmap file operation handler of a driver.
2471 * This function maps one plane of one of the available video buffers to
2472 * userspace. To map whole video memory allocated on reqbufs, this function
2473 * has to be called once per each plane per each buffer previously allocated.
2475 * When the userspace application calls mmap, it passes to it an offset returned
2476 * to it earlier by the means of vidioc_querybuf handler. That offset acts as
2477 * a "cookie", which is then used to identify the plane to be mapped.
2478 * This function finds a plane with a matching offset and a mapping is performed
2479 * by the means of a provided memory operation.
2481 * The return values from this function are intended to be directly returned
2482 * from the mmap handler in driver.
2484 int vb2_mmap(struct vb2_queue
*q
, struct vm_area_struct
*vma
)
2486 unsigned long off
= vma
->vm_pgoff
<< PAGE_SHIFT
;
2487 struct vb2_buffer
*vb
;
2488 unsigned int buffer
= 0, plane
= 0;
2490 unsigned long length
;
2492 if (q
->memory
!= V4L2_MEMORY_MMAP
) {
2493 dprintk(1, "queue is not currently set up for mmap\n");
2498 * Check memory area access mode.
2500 if (!(vma
->vm_flags
& VM_SHARED
)) {
2501 dprintk(1, "invalid vma flags, VM_SHARED needed\n");
2504 if (V4L2_TYPE_IS_OUTPUT(q
->type
)) {
2505 if (!(vma
->vm_flags
& VM_WRITE
)) {
2506 dprintk(1, "invalid vma flags, VM_WRITE needed\n");
2510 if (!(vma
->vm_flags
& VM_READ
)) {
2511 dprintk(1, "invalid vma flags, VM_READ needed\n");
2515 if (vb2_fileio_is_active(q
)) {
2516 dprintk(1, "mmap: file io in progress\n");
2521 * Find the plane corresponding to the offset passed by userspace.
2523 ret
= __find_plane_by_offset(q
, off
, &buffer
, &plane
);
2527 vb
= q
->bufs
[buffer
];
2530 * MMAP requires page_aligned buffers.
2531 * The buffer length was page_aligned at __vb2_buf_mem_alloc(),
2532 * so, we need to do the same here.
2534 length
= PAGE_ALIGN(vb
->v4l2_planes
[plane
].length
);
2535 if (length
< (vma
->vm_end
- vma
->vm_start
)) {
2537 "MMAP invalid, as it would overflow buffer length\n");
2541 mutex_lock(&q
->mmap_lock
);
2542 ret
= call_memop(vb
, mmap
, vb
->planes
[plane
].mem_priv
, vma
);
2543 mutex_unlock(&q
->mmap_lock
);
2547 dprintk(3, "buffer %d, plane %d successfully mapped\n", buffer
, plane
);
2550 EXPORT_SYMBOL_GPL(vb2_mmap
);
2553 unsigned long vb2_get_unmapped_area(struct vb2_queue
*q
,
2556 unsigned long pgoff
,
2557 unsigned long flags
)
2559 unsigned long off
= pgoff
<< PAGE_SHIFT
;
2560 struct vb2_buffer
*vb
;
2561 unsigned int buffer
, plane
;
2565 if (q
->memory
!= V4L2_MEMORY_MMAP
) {
2566 dprintk(1, "queue is not currently set up for mmap\n");
2571 * Find the plane corresponding to the offset passed by userspace.
2573 ret
= __find_plane_by_offset(q
, off
, &buffer
, &plane
);
2577 vb
= q
->bufs
[buffer
];
2579 vaddr
= vb2_plane_vaddr(vb
, plane
);
2580 return vaddr
? (unsigned long)vaddr
: -EINVAL
;
2582 EXPORT_SYMBOL_GPL(vb2_get_unmapped_area
);
2585 static int __vb2_init_fileio(struct vb2_queue
*q
, int read
);
2586 static int __vb2_cleanup_fileio(struct vb2_queue
*q
);
2589 * vb2_poll() - implements poll userspace operation
2590 * @q: videobuf2 queue
2591 * @file: file argument passed to the poll file operation handler
2592 * @wait: wait argument passed to the poll file operation handler
2594 * This function implements poll file operation handler for a driver.
2595 * For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will
2596 * be informed that the file descriptor of a video device is available for
2598 * For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor
2599 * will be reported as available for writing.
2601 * If the driver uses struct v4l2_fh, then vb2_poll() will also check for any
2604 * The return values from this function are intended to be directly returned
2605 * from poll handler in driver.
2607 unsigned int vb2_poll(struct vb2_queue
*q
, struct file
*file
, poll_table
*wait
)
2609 struct video_device
*vfd
= video_devdata(file
);
2610 unsigned long req_events
= poll_requested_events(wait
);
2611 struct vb2_buffer
*vb
= NULL
;
2612 unsigned int res
= 0;
2613 unsigned long flags
;
2615 if (test_bit(V4L2_FL_USES_V4L2_FH
, &vfd
->flags
)) {
2616 struct v4l2_fh
*fh
= file
->private_data
;
2618 if (v4l2_event_pending(fh
))
2620 else if (req_events
& POLLPRI
)
2621 poll_wait(file
, &fh
->wait
, wait
);
2624 if (!V4L2_TYPE_IS_OUTPUT(q
->type
) && !(req_events
& (POLLIN
| POLLRDNORM
)))
2626 if (V4L2_TYPE_IS_OUTPUT(q
->type
) && !(req_events
& (POLLOUT
| POLLWRNORM
)))
2630 * Start file I/O emulator only if streaming API has not been used yet.
2632 if (q
->num_buffers
== 0 && !vb2_fileio_is_active(q
)) {
2633 if (!V4L2_TYPE_IS_OUTPUT(q
->type
) && (q
->io_modes
& VB2_READ
) &&
2634 (req_events
& (POLLIN
| POLLRDNORM
))) {
2635 if (__vb2_init_fileio(q
, 1))
2636 return res
| POLLERR
;
2638 if (V4L2_TYPE_IS_OUTPUT(q
->type
) && (q
->io_modes
& VB2_WRITE
) &&
2639 (req_events
& (POLLOUT
| POLLWRNORM
))) {
2640 if (__vb2_init_fileio(q
, 0))
2641 return res
| POLLERR
;
2643 * Write to OUTPUT queue can be done immediately.
2645 return res
| POLLOUT
| POLLWRNORM
;
2650 * There is nothing to wait for if the queue isn't streaming, or if the
2651 * error flag is set.
2653 if (!vb2_is_streaming(q
) || q
->error
)
2654 return res
| POLLERR
;
2656 * For compatibility with vb1: if QBUF hasn't been called yet, then
2657 * return POLLERR as well. This only affects capture queues, output
2658 * queues will always initialize waiting_for_buffers to false.
2660 if (q
->waiting_for_buffers
)
2661 return res
| POLLERR
;
2664 * For output streams you can write as long as there are fewer buffers
2665 * queued than there are buffers available.
2667 if (V4L2_TYPE_IS_OUTPUT(q
->type
) && q
->queued_count
< q
->num_buffers
)
2668 return res
| POLLOUT
| POLLWRNORM
;
2670 if (list_empty(&q
->done_list
)) {
2672 * If the last buffer was dequeued from a capture queue,
2673 * return immediately. DQBUF will return -EPIPE.
2675 if (q
->last_buffer_dequeued
)
2676 return res
| POLLIN
| POLLRDNORM
;
2678 poll_wait(file
, &q
->done_wq
, wait
);
2682 * Take first buffer available for dequeuing.
2684 spin_lock_irqsave(&q
->done_lock
, flags
);
2685 if (!list_empty(&q
->done_list
))
2686 vb
= list_first_entry(&q
->done_list
, struct vb2_buffer
,
2688 spin_unlock_irqrestore(&q
->done_lock
, flags
);
2690 if (vb
&& (vb
->state
== VB2_BUF_STATE_DONE
2691 || vb
->state
== VB2_BUF_STATE_ERROR
)) {
2692 return (V4L2_TYPE_IS_OUTPUT(q
->type
)) ?
2693 res
| POLLOUT
| POLLWRNORM
:
2694 res
| POLLIN
| POLLRDNORM
;
2698 EXPORT_SYMBOL_GPL(vb2_poll
);
2701 * vb2_queue_init() - initialize a videobuf2 queue
2702 * @q: videobuf2 queue; this structure should be allocated in driver
2704 * The vb2_queue structure should be allocated by the driver. The driver is
2705 * responsible of clearing it's content and setting initial values for some
2706 * required entries before calling this function.
2707 * q->ops, q->mem_ops, q->type and q->io_modes are mandatory. Please refer
2708 * to the struct vb2_queue description in include/media/videobuf2-core.h
2709 * for more information.
2711 int vb2_queue_init(struct vb2_queue
*q
)
2718 WARN_ON(!q
->mem_ops
) ||
2719 WARN_ON(!q
->type
) ||
2720 WARN_ON(!q
->io_modes
) ||
2721 WARN_ON(!q
->ops
->queue_setup
) ||
2722 WARN_ON(!q
->ops
->buf_queue
) ||
2723 WARN_ON(q
->timestamp_flags
&
2724 ~(V4L2_BUF_FLAG_TIMESTAMP_MASK
|
2725 V4L2_BUF_FLAG_TSTAMP_SRC_MASK
)))
2728 /* Warn that the driver should choose an appropriate timestamp type */
2729 WARN_ON((q
->timestamp_flags
& V4L2_BUF_FLAG_TIMESTAMP_MASK
) ==
2730 V4L2_BUF_FLAG_TIMESTAMP_UNKNOWN
);
2732 INIT_LIST_HEAD(&q
->queued_list
);
2733 INIT_LIST_HEAD(&q
->done_list
);
2734 spin_lock_init(&q
->done_lock
);
2735 mutex_init(&q
->mmap_lock
);
2736 init_waitqueue_head(&q
->done_wq
);
2738 if (q
->buf_struct_size
== 0)
2739 q
->buf_struct_size
= sizeof(struct vb2_buffer
);
2743 EXPORT_SYMBOL_GPL(vb2_queue_init
);
2746 * vb2_queue_release() - stop streaming, release the queue and free memory
2747 * @q: videobuf2 queue
2749 * This function stops streaming and performs necessary clean ups, including
2750 * freeing video buffer memory. The driver is responsible for freeing
2751 * the vb2_queue structure itself.
2753 void vb2_queue_release(struct vb2_queue
*q
)
2755 __vb2_cleanup_fileio(q
);
2756 __vb2_queue_cancel(q
);
2757 mutex_lock(&q
->mmap_lock
);
2758 __vb2_queue_free(q
, q
->num_buffers
);
2759 mutex_unlock(&q
->mmap_lock
);
2761 EXPORT_SYMBOL_GPL(vb2_queue_release
);
2764 * struct vb2_fileio_buf - buffer context used by file io emulator
2766 * vb2 provides a compatibility layer and emulator of file io (read and
2767 * write) calls on top of streaming API. This structure is used for
2768 * tracking context related to the buffers.
2770 struct vb2_fileio_buf
{
2774 unsigned int queued
:1;
2778 * struct vb2_fileio_data - queue context used by file io emulator
2780 * @cur_index: the index of the buffer currently being read from or
2781 * written to. If equal to q->num_buffers then a new buffer
2783 * @initial_index: in the read() case all buffers are queued up immediately
2784 * in __vb2_init_fileio() and __vb2_perform_fileio() just cycles
2785 * buffers. However, in the write() case no buffers are initially
2786 * queued, instead whenever a buffer is full it is queued up by
2787 * __vb2_perform_fileio(). Only once all available buffers have
2788 * been queued up will __vb2_perform_fileio() start to dequeue
2789 * buffers. This means that initially __vb2_perform_fileio()
2790 * needs to know what buffer index to use when it is queuing up
2791 * the buffers for the first time. That initial index is stored
2792 * in this field. Once it is equal to q->num_buffers all
2793 * available buffers have been queued and __vb2_perform_fileio()
2794 * should start the normal dequeue/queue cycle.
2796 * vb2 provides a compatibility layer and emulator of file io (read and
2797 * write) calls on top of streaming API. For proper operation it required
2798 * this structure to save the driver state between each call of the read
2799 * or write function.
2801 struct vb2_fileio_data
{
2802 struct v4l2_requestbuffers req
;
2803 struct v4l2_plane p
;
2804 struct v4l2_buffer b
;
2805 struct vb2_fileio_buf bufs
[VIDEO_MAX_FRAME
];
2806 unsigned int cur_index
;
2807 unsigned int initial_index
;
2808 unsigned int q_count
;
2809 unsigned int dq_count
;
2810 unsigned read_once
:1;
2811 unsigned write_immediately
:1;
2815 * __vb2_init_fileio() - initialize file io emulator
2816 * @q: videobuf2 queue
2817 * @read: mode selector (1 means read, 0 means write)
2819 static int __vb2_init_fileio(struct vb2_queue
*q
, int read
)
2821 struct vb2_fileio_data
*fileio
;
2823 unsigned int count
= 0;
2828 if (WARN_ON((read
&& !(q
->io_modes
& VB2_READ
)) ||
2829 (!read
&& !(q
->io_modes
& VB2_WRITE
))))
2833 * Check if device supports mapping buffers to kernel virtual space.
2835 if (!q
->mem_ops
->vaddr
)
2839 * Check if streaming api has not been already activated.
2841 if (q
->streaming
|| q
->num_buffers
> 0)
2845 * Start with count 1, driver can increase it in queue_setup()
2849 dprintk(3, "setting up file io: mode %s, count %d, read_once %d, write_immediately %d\n",
2850 (read
) ? "read" : "write", count
, q
->fileio_read_once
,
2851 q
->fileio_write_immediately
);
2853 fileio
= kzalloc(sizeof(struct vb2_fileio_data
), GFP_KERNEL
);
2857 fileio
->read_once
= q
->fileio_read_once
;
2858 fileio
->write_immediately
= q
->fileio_write_immediately
;
2861 * Request buffers and use MMAP type to force driver
2862 * to allocate buffers by itself.
2864 fileio
->req
.count
= count
;
2865 fileio
->req
.memory
= V4L2_MEMORY_MMAP
;
2866 fileio
->req
.type
= q
->type
;
2868 ret
= __reqbufs(q
, &fileio
->req
);
2873 * Check if plane_count is correct
2874 * (multiplane buffers are not supported).
2876 if (q
->bufs
[0]->num_planes
!= 1) {
2882 * Get kernel address of each buffer.
2884 for (i
= 0; i
< q
->num_buffers
; i
++) {
2885 fileio
->bufs
[i
].vaddr
= vb2_plane_vaddr(q
->bufs
[i
], 0);
2886 if (fileio
->bufs
[i
].vaddr
== NULL
) {
2890 fileio
->bufs
[i
].size
= vb2_plane_size(q
->bufs
[i
], 0);
2894 * Read mode requires pre queuing of all buffers.
2897 bool is_multiplanar
= V4L2_TYPE_IS_MULTIPLANAR(q
->type
);
2900 * Queue all buffers.
2902 for (i
= 0; i
< q
->num_buffers
; i
++) {
2903 struct v4l2_buffer
*b
= &fileio
->b
;
2905 memset(b
, 0, sizeof(*b
));
2907 if (is_multiplanar
) {
2908 memset(&fileio
->p
, 0, sizeof(fileio
->p
));
2909 b
->m
.planes
= &fileio
->p
;
2912 b
->memory
= q
->memory
;
2914 ret
= vb2_internal_qbuf(q
, b
);
2917 fileio
->bufs
[i
].queued
= 1;
2920 * All buffers have been queued, so mark that by setting
2921 * initial_index to q->num_buffers
2923 fileio
->initial_index
= q
->num_buffers
;
2924 fileio
->cur_index
= q
->num_buffers
;
2930 ret
= vb2_internal_streamon(q
, q
->type
);
2937 fileio
->req
.count
= 0;
2938 __reqbufs(q
, &fileio
->req
);
2947 * __vb2_cleanup_fileio() - free resourced used by file io emulator
2948 * @q: videobuf2 queue
2950 static int __vb2_cleanup_fileio(struct vb2_queue
*q
)
2952 struct vb2_fileio_data
*fileio
= q
->fileio
;
2955 vb2_internal_streamoff(q
, q
->type
);
2957 fileio
->req
.count
= 0;
2958 vb2_reqbufs(q
, &fileio
->req
);
2960 dprintk(3, "file io emulator closed\n");
2966 * __vb2_perform_fileio() - perform a single file io (read or write) operation
2967 * @q: videobuf2 queue
2968 * @data: pointed to target userspace buffer
2969 * @count: number of bytes to read or write
2970 * @ppos: file handle position tracking pointer
2971 * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking)
2972 * @read: access mode selector (1 means read, 0 means write)
2974 static size_t __vb2_perform_fileio(struct vb2_queue
*q
, char __user
*data
, size_t count
,
2975 loff_t
*ppos
, int nonblock
, int read
)
2977 struct vb2_fileio_data
*fileio
;
2978 struct vb2_fileio_buf
*buf
;
2979 bool is_multiplanar
= V4L2_TYPE_IS_MULTIPLANAR(q
->type
);
2981 * When using write() to write data to an output video node the vb2 core
2982 * should set timestamps if V4L2_BUF_FLAG_TIMESTAMP_COPY is set. Nobody
2983 * else is able to provide this information with the write() operation.
2985 bool set_timestamp
= !read
&&
2986 (q
->timestamp_flags
& V4L2_BUF_FLAG_TIMESTAMP_MASK
) ==
2987 V4L2_BUF_FLAG_TIMESTAMP_COPY
;
2990 dprintk(3, "mode %s, offset %ld, count %zd, %sblocking\n",
2991 read
? "read" : "write", (long)*ppos
, count
,
2992 nonblock
? "non" : "");
2998 * Initialize emulator on first call.
3000 if (!vb2_fileio_is_active(q
)) {
3001 ret
= __vb2_init_fileio(q
, read
);
3002 dprintk(3, "vb2_init_fileio result: %d\n", ret
);
3009 * Check if we need to dequeue the buffer.
3011 index
= fileio
->cur_index
;
3012 if (index
>= q
->num_buffers
) {
3014 * Call vb2_dqbuf to get buffer back.
3016 memset(&fileio
->b
, 0, sizeof(fileio
->b
));
3017 fileio
->b
.type
= q
->type
;
3018 fileio
->b
.memory
= q
->memory
;
3019 if (is_multiplanar
) {
3020 memset(&fileio
->p
, 0, sizeof(fileio
->p
));
3021 fileio
->b
.m
.planes
= &fileio
->p
;
3022 fileio
->b
.length
= 1;
3024 ret
= vb2_internal_dqbuf(q
, &fileio
->b
, nonblock
);
3025 dprintk(5, "vb2_dqbuf result: %d\n", ret
);
3028 fileio
->dq_count
+= 1;
3030 fileio
->cur_index
= index
= fileio
->b
.index
;
3031 buf
= &fileio
->bufs
[index
];
3034 * Get number of bytes filled by the driver
3038 buf
->size
= read
? vb2_get_plane_payload(q
->bufs
[index
], 0)
3039 : vb2_plane_size(q
->bufs
[index
], 0);
3040 /* Compensate for data_offset on read in the multiplanar case. */
3041 if (is_multiplanar
&& read
&&
3042 fileio
->b
.m
.planes
[0].data_offset
< buf
->size
) {
3043 buf
->pos
= fileio
->b
.m
.planes
[0].data_offset
;
3044 buf
->size
-= buf
->pos
;
3047 buf
= &fileio
->bufs
[index
];
3051 * Limit count on last few bytes of the buffer.
3053 if (buf
->pos
+ count
> buf
->size
) {
3054 count
= buf
->size
- buf
->pos
;
3055 dprintk(5, "reducing read count: %zd\n", count
);
3059 * Transfer data to userspace.
3061 dprintk(3, "copying %zd bytes - buffer %d, offset %u\n",
3062 count
, index
, buf
->pos
);
3064 ret
= copy_to_user(data
, buf
->vaddr
+ buf
->pos
, count
);
3066 ret
= copy_from_user(buf
->vaddr
+ buf
->pos
, data
, count
);
3068 dprintk(3, "error copying data\n");
3079 * Queue next buffer if required.
3081 if (buf
->pos
== buf
->size
|| (!read
&& fileio
->write_immediately
)) {
3083 * Check if this is the last buffer to read.
3085 if (read
&& fileio
->read_once
&& fileio
->dq_count
== 1) {
3086 dprintk(3, "read limit reached\n");
3087 return __vb2_cleanup_fileio(q
);
3091 * Call vb2_qbuf and give buffer to the driver.
3093 memset(&fileio
->b
, 0, sizeof(fileio
->b
));
3094 fileio
->b
.type
= q
->type
;
3095 fileio
->b
.memory
= q
->memory
;
3096 fileio
->b
.index
= index
;
3097 fileio
->b
.bytesused
= buf
->pos
;
3098 if (is_multiplanar
) {
3099 memset(&fileio
->p
, 0, sizeof(fileio
->p
));
3100 fileio
->p
.bytesused
= buf
->pos
;
3101 fileio
->b
.m
.planes
= &fileio
->p
;
3102 fileio
->b
.length
= 1;
3105 v4l2_get_timestamp(&fileio
->b
.timestamp
);
3106 ret
= vb2_internal_qbuf(q
, &fileio
->b
);
3107 dprintk(5, "vb2_dbuf result: %d\n", ret
);
3112 * Buffer has been queued, update the status
3116 buf
->size
= vb2_plane_size(q
->bufs
[index
], 0);
3117 fileio
->q_count
+= 1;
3119 * If we are queuing up buffers for the first time, then
3120 * increase initial_index by one.
3122 if (fileio
->initial_index
< q
->num_buffers
)
3123 fileio
->initial_index
++;
3125 * The next buffer to use is either a buffer that's going to be
3126 * queued for the first time (initial_index < q->num_buffers)
3127 * or it is equal to q->num_buffers, meaning that the next
3128 * time we need to dequeue a buffer since we've now queued up
3129 * all the 'first time' buffers.
3131 fileio
->cur_index
= fileio
->initial_index
;
3135 * Return proper number of bytes processed.
3142 size_t vb2_read(struct vb2_queue
*q
, char __user
*data
, size_t count
,
3143 loff_t
*ppos
, int nonblocking
)
3145 return __vb2_perform_fileio(q
, data
, count
, ppos
, nonblocking
, 1);
3147 EXPORT_SYMBOL_GPL(vb2_read
);
3149 size_t vb2_write(struct vb2_queue
*q
, const char __user
*data
, size_t count
,
3150 loff_t
*ppos
, int nonblocking
)
3152 return __vb2_perform_fileio(q
, (char __user
*) data
, count
,
3153 ppos
, nonblocking
, 0);
3155 EXPORT_SYMBOL_GPL(vb2_write
);
3157 struct vb2_threadio_data
{
3158 struct task_struct
*thread
;
3164 static int vb2_thread(void *data
)
3166 struct vb2_queue
*q
= data
;
3167 struct vb2_threadio_data
*threadio
= q
->threadio
;
3168 struct vb2_fileio_data
*fileio
= q
->fileio
;
3169 bool set_timestamp
= false;
3174 if (V4L2_TYPE_IS_OUTPUT(q
->type
)) {
3175 prequeue
= q
->num_buffers
;
3177 (q
->timestamp_flags
& V4L2_BUF_FLAG_TIMESTAMP_MASK
) ==
3178 V4L2_BUF_FLAG_TIMESTAMP_COPY
;
3184 struct vb2_buffer
*vb
;
3187 * Call vb2_dqbuf to get buffer back.
3189 memset(&fileio
->b
, 0, sizeof(fileio
->b
));
3190 fileio
->b
.type
= q
->type
;
3191 fileio
->b
.memory
= q
->memory
;
3193 fileio
->b
.index
= index
++;
3196 call_void_qop(q
, wait_finish
, q
);
3197 if (!threadio
->stop
)
3198 ret
= vb2_internal_dqbuf(q
, &fileio
->b
, 0);
3199 call_void_qop(q
, wait_prepare
, q
);
3200 dprintk(5, "file io: vb2_dqbuf result: %d\n", ret
);
3202 if (ret
|| threadio
->stop
)
3206 vb
= q
->bufs
[fileio
->b
.index
];
3207 if (!(fileio
->b
.flags
& V4L2_BUF_FLAG_ERROR
))
3208 if (threadio
->fnc(vb
, threadio
->priv
))
3210 call_void_qop(q
, wait_finish
, q
);
3212 v4l2_get_timestamp(&fileio
->b
.timestamp
);
3213 if (!threadio
->stop
)
3214 ret
= vb2_internal_qbuf(q
, &fileio
->b
);
3215 call_void_qop(q
, wait_prepare
, q
);
3216 if (ret
|| threadio
->stop
)
3220 /* Hmm, linux becomes *very* unhappy without this ... */
3221 while (!kthread_should_stop()) {
3222 set_current_state(TASK_INTERRUPTIBLE
);
3229 * This function should not be used for anything else but the videobuf2-dvb
3230 * support. If you think you have another good use-case for this, then please
3231 * contact the linux-media mailinglist first.
3233 int vb2_thread_start(struct vb2_queue
*q
, vb2_thread_fnc fnc
, void *priv
,
3234 const char *thread_name
)
3236 struct vb2_threadio_data
*threadio
;
3243 if (WARN_ON(q
->fileio
))
3246 threadio
= kzalloc(sizeof(*threadio
), GFP_KERNEL
);
3247 if (threadio
== NULL
)
3249 threadio
->fnc
= fnc
;
3250 threadio
->priv
= priv
;
3252 ret
= __vb2_init_fileio(q
, !V4L2_TYPE_IS_OUTPUT(q
->type
));
3253 dprintk(3, "file io: vb2_init_fileio result: %d\n", ret
);
3256 q
->threadio
= threadio
;
3257 threadio
->thread
= kthread_run(vb2_thread
, q
, "vb2-%s", thread_name
);
3258 if (IS_ERR(threadio
->thread
)) {
3259 ret
= PTR_ERR(threadio
->thread
);
3260 threadio
->thread
= NULL
;
3266 __vb2_cleanup_fileio(q
);
3271 EXPORT_SYMBOL_GPL(vb2_thread_start
);
3273 int vb2_thread_stop(struct vb2_queue
*q
)
3275 struct vb2_threadio_data
*threadio
= q
->threadio
;
3278 if (threadio
== NULL
)
3280 threadio
->stop
= true;
3281 /* Wake up all pending sleeps in the thread */
3283 err
= kthread_stop(threadio
->thread
);
3284 __vb2_cleanup_fileio(q
);
3285 threadio
->thread
= NULL
;
3290 EXPORT_SYMBOL_GPL(vb2_thread_stop
);
3293 * The following functions are not part of the vb2 core API, but are helper
3294 * functions that plug into struct v4l2_ioctl_ops, struct v4l2_file_operations
3295 * and struct vb2_ops.
3296 * They contain boilerplate code that most if not all drivers have to do
3297 * and so they simplify the driver code.
3300 /* The queue is busy if there is a owner and you are not that owner. */
3301 static inline bool vb2_queue_is_busy(struct video_device
*vdev
, struct file
*file
)
3303 return vdev
->queue
->owner
&& vdev
->queue
->owner
!= file
->private_data
;
3306 /* vb2 ioctl helpers */
3308 int vb2_ioctl_reqbufs(struct file
*file
, void *priv
,
3309 struct v4l2_requestbuffers
*p
)
3311 struct video_device
*vdev
= video_devdata(file
);
3312 int res
= __verify_memory_type(vdev
->queue
, p
->memory
, p
->type
);
3316 if (vb2_queue_is_busy(vdev
, file
))
3318 res
= __reqbufs(vdev
->queue
, p
);
3319 /* If count == 0, then the owner has released all buffers and he
3320 is no longer owner of the queue. Otherwise we have a new owner. */
3322 vdev
->queue
->owner
= p
->count
? file
->private_data
: NULL
;
3325 EXPORT_SYMBOL_GPL(vb2_ioctl_reqbufs
);
3327 int vb2_ioctl_create_bufs(struct file
*file
, void *priv
,
3328 struct v4l2_create_buffers
*p
)
3330 struct video_device
*vdev
= video_devdata(file
);
3331 int res
= __verify_memory_type(vdev
->queue
, p
->memory
, p
->format
.type
);
3333 p
->index
= vdev
->queue
->num_buffers
;
3334 /* If count == 0, then just check if memory and type are valid.
3335 Any -EBUSY result from __verify_memory_type can be mapped to 0. */
3337 return res
!= -EBUSY
? res
: 0;
3340 if (vb2_queue_is_busy(vdev
, file
))
3342 res
= __create_bufs(vdev
->queue
, p
);
3344 vdev
->queue
->owner
= file
->private_data
;
3347 EXPORT_SYMBOL_GPL(vb2_ioctl_create_bufs
);
3349 int vb2_ioctl_prepare_buf(struct file
*file
, void *priv
,
3350 struct v4l2_buffer
*p
)
3352 struct video_device
*vdev
= video_devdata(file
);
3354 if (vb2_queue_is_busy(vdev
, file
))
3356 return vb2_prepare_buf(vdev
->queue
, p
);
3358 EXPORT_SYMBOL_GPL(vb2_ioctl_prepare_buf
);
3360 int vb2_ioctl_querybuf(struct file
*file
, void *priv
, struct v4l2_buffer
*p
)
3362 struct video_device
*vdev
= video_devdata(file
);
3364 /* No need to call vb2_queue_is_busy(), anyone can query buffers. */
3365 return vb2_querybuf(vdev
->queue
, p
);
3367 EXPORT_SYMBOL_GPL(vb2_ioctl_querybuf
);
3369 int vb2_ioctl_qbuf(struct file
*file
, void *priv
, struct v4l2_buffer
*p
)
3371 struct video_device
*vdev
= video_devdata(file
);
3373 if (vb2_queue_is_busy(vdev
, file
))
3375 return vb2_qbuf(vdev
->queue
, p
);
3377 EXPORT_SYMBOL_GPL(vb2_ioctl_qbuf
);
3379 int vb2_ioctl_dqbuf(struct file
*file
, void *priv
, struct v4l2_buffer
*p
)
3381 struct video_device
*vdev
= video_devdata(file
);
3383 if (vb2_queue_is_busy(vdev
, file
))
3385 return vb2_dqbuf(vdev
->queue
, p
, file
->f_flags
& O_NONBLOCK
);
3387 EXPORT_SYMBOL_GPL(vb2_ioctl_dqbuf
);
3389 int vb2_ioctl_streamon(struct file
*file
, void *priv
, enum v4l2_buf_type i
)
3391 struct video_device
*vdev
= video_devdata(file
);
3393 if (vb2_queue_is_busy(vdev
, file
))
3395 return vb2_streamon(vdev
->queue
, i
);
3397 EXPORT_SYMBOL_GPL(vb2_ioctl_streamon
);
3399 int vb2_ioctl_streamoff(struct file
*file
, void *priv
, enum v4l2_buf_type i
)
3401 struct video_device
*vdev
= video_devdata(file
);
3403 if (vb2_queue_is_busy(vdev
, file
))
3405 return vb2_streamoff(vdev
->queue
, i
);
3407 EXPORT_SYMBOL_GPL(vb2_ioctl_streamoff
);
3409 int vb2_ioctl_expbuf(struct file
*file
, void *priv
, struct v4l2_exportbuffer
*p
)
3411 struct video_device
*vdev
= video_devdata(file
);
3413 if (vb2_queue_is_busy(vdev
, file
))
3415 return vb2_expbuf(vdev
->queue
, p
);
3417 EXPORT_SYMBOL_GPL(vb2_ioctl_expbuf
);
3419 /* v4l2_file_operations helpers */
3421 int vb2_fop_mmap(struct file
*file
, struct vm_area_struct
*vma
)
3423 struct video_device
*vdev
= video_devdata(file
);
3425 return vb2_mmap(vdev
->queue
, vma
);
3427 EXPORT_SYMBOL_GPL(vb2_fop_mmap
);
3429 int _vb2_fop_release(struct file
*file
, struct mutex
*lock
)
3431 struct video_device
*vdev
= video_devdata(file
);
3435 if (file
->private_data
== vdev
->queue
->owner
) {
3436 vb2_queue_release(vdev
->queue
);
3437 vdev
->queue
->owner
= NULL
;
3441 return v4l2_fh_release(file
);
3443 EXPORT_SYMBOL_GPL(_vb2_fop_release
);
3445 int vb2_fop_release(struct file
*file
)
3447 struct video_device
*vdev
= video_devdata(file
);
3448 struct mutex
*lock
= vdev
->queue
->lock
? vdev
->queue
->lock
: vdev
->lock
;
3450 return _vb2_fop_release(file
, lock
);
3452 EXPORT_SYMBOL_GPL(vb2_fop_release
);
3454 ssize_t
vb2_fop_write(struct file
*file
, const char __user
*buf
,
3455 size_t count
, loff_t
*ppos
)
3457 struct video_device
*vdev
= video_devdata(file
);
3458 struct mutex
*lock
= vdev
->queue
->lock
? vdev
->queue
->lock
: vdev
->lock
;
3461 if (!(vdev
->queue
->io_modes
& VB2_WRITE
))
3463 if (lock
&& mutex_lock_interruptible(lock
))
3464 return -ERESTARTSYS
;
3465 if (vb2_queue_is_busy(vdev
, file
))
3467 err
= vb2_write(vdev
->queue
, buf
, count
, ppos
,
3468 file
->f_flags
& O_NONBLOCK
);
3469 if (vdev
->queue
->fileio
)
3470 vdev
->queue
->owner
= file
->private_data
;
3476 EXPORT_SYMBOL_GPL(vb2_fop_write
);
3478 ssize_t
vb2_fop_read(struct file
*file
, char __user
*buf
,
3479 size_t count
, loff_t
*ppos
)
3481 struct video_device
*vdev
= video_devdata(file
);
3482 struct mutex
*lock
= vdev
->queue
->lock
? vdev
->queue
->lock
: vdev
->lock
;
3485 if (!(vdev
->queue
->io_modes
& VB2_READ
))
3487 if (lock
&& mutex_lock_interruptible(lock
))
3488 return -ERESTARTSYS
;
3489 if (vb2_queue_is_busy(vdev
, file
))
3491 err
= vb2_read(vdev
->queue
, buf
, count
, ppos
,
3492 file
->f_flags
& O_NONBLOCK
);
3493 if (vdev
->queue
->fileio
)
3494 vdev
->queue
->owner
= file
->private_data
;
3500 EXPORT_SYMBOL_GPL(vb2_fop_read
);
3502 unsigned int vb2_fop_poll(struct file
*file
, poll_table
*wait
)
3504 struct video_device
*vdev
= video_devdata(file
);
3505 struct vb2_queue
*q
= vdev
->queue
;
3506 struct mutex
*lock
= q
->lock
? q
->lock
: vdev
->lock
;
3511 * If this helper doesn't know how to lock, then you shouldn't be using
3512 * it but you should write your own.
3516 if (lock
&& mutex_lock_interruptible(lock
))
3521 res
= vb2_poll(vdev
->queue
, file
, wait
);
3523 /* If fileio was started, then we have a new queue owner. */
3524 if (!fileio
&& q
->fileio
)
3525 q
->owner
= file
->private_data
;
3530 EXPORT_SYMBOL_GPL(vb2_fop_poll
);
3533 unsigned long vb2_fop_get_unmapped_area(struct file
*file
, unsigned long addr
,
3534 unsigned long len
, unsigned long pgoff
, unsigned long flags
)
3536 struct video_device
*vdev
= video_devdata(file
);
3538 return vb2_get_unmapped_area(vdev
->queue
, addr
, len
, pgoff
, flags
);
3540 EXPORT_SYMBOL_GPL(vb2_fop_get_unmapped_area
);
3543 /* vb2_ops helpers. Only use if vq->lock is non-NULL. */
3545 void vb2_ops_wait_prepare(struct vb2_queue
*vq
)
3547 mutex_unlock(vq
->lock
);
3549 EXPORT_SYMBOL_GPL(vb2_ops_wait_prepare
);
3551 void vb2_ops_wait_finish(struct vb2_queue
*vq
)
3553 mutex_lock(vq
->lock
);
3555 EXPORT_SYMBOL_GPL(vb2_ops_wait_finish
);
3557 MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2");
3558 MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski");
3559 MODULE_LICENSE("GPL");