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 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation.
14 #include <linux/err.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
18 #include <linux/poll.h>
19 #include <linux/slab.h>
20 #include <linux/sched.h>
22 #include <media/v4l2-dev.h>
23 #include <media/v4l2-fh.h>
24 #include <media/v4l2-event.h>
25 #include <media/videobuf2-core.h>
28 module_param(debug, int, 0644);
30 #define dprintk(level, fmt, arg...) \
33 printk(KERN_DEBUG "vb2: " fmt, ## arg); \
36 #ifdef CONFIG_VIDEO_ADV_DEBUG
39 * If advanced debugging is on, then count how often each op is called
40 * successfully, which can either be per-buffer or per-queue.
42 * This makes it easy to check that the 'init' and 'cleanup'
43 * (and variations thereof) stay balanced.
46 #define log_memop(vb, op) \
47 dprintk(2, "call_memop(%p, %d, %s)%s\n", \
48 (vb)->vb2_queue, (vb)->v4l2_buf.index, #op, \
49 (vb)->vb2_queue->mem_ops->op ? "" : " (nop)")
51 #define call_memop(vb, op, args...) \
53 struct vb2_queue *_q = (vb)->vb2_queue; \
57 err = _q->mem_ops->op ? _q->mem_ops->op(args) : 0; \
59 (vb)->cnt_mem_ ## op++; \
63 #define call_ptr_memop(vb, op, args...) \
65 struct vb2_queue *_q = (vb)->vb2_queue; \
69 ptr = _q->mem_ops->op ? _q->mem_ops->op(args) : NULL; \
70 if (!IS_ERR_OR_NULL(ptr)) \
71 (vb)->cnt_mem_ ## op++; \
75 #define call_void_memop(vb, op, args...) \
77 struct vb2_queue *_q = (vb)->vb2_queue; \
80 if (_q->mem_ops->op) \
81 _q->mem_ops->op(args); \
82 (vb)->cnt_mem_ ## op++; \
85 #define log_qop(q, op) \
86 dprintk(2, "call_qop(%p, %s)%s\n", q, #op, \
87 (q)->ops->op ? "" : " (nop)")
89 #define call_qop(q, op, args...) \
94 err = (q)->ops->op ? (q)->ops->op(args) : 0; \
100 #define call_void_qop(q, op, args...) \
104 (q)->ops->op(args); \
108 #define log_vb_qop(vb, op, args...) \
109 dprintk(2, "call_vb_qop(%p, %d, %s)%s\n", \
110 (vb)->vb2_queue, (vb)->v4l2_buf.index, #op, \
111 (vb)->vb2_queue->ops->op ? "" : " (nop)")
113 #define call_vb_qop(vb, op, args...) \
117 log_vb_qop(vb, op); \
118 err = (vb)->vb2_queue->ops->op ? \
119 (vb)->vb2_queue->ops->op(args) : 0; \
121 (vb)->cnt_ ## op++; \
125 #define call_void_vb_qop(vb, op, args...) \
127 log_vb_qop(vb, op); \
128 if ((vb)->vb2_queue->ops->op) \
129 (vb)->vb2_queue->ops->op(args); \
130 (vb)->cnt_ ## op++; \
135 #define call_memop(vb, op, args...) \
136 ((vb)->vb2_queue->mem_ops->op ? \
137 (vb)->vb2_queue->mem_ops->op(args) : 0)
139 #define call_ptr_memop(vb, op, args...) \
140 ((vb)->vb2_queue->mem_ops->op ? \
141 (vb)->vb2_queue->mem_ops->op(args) : NULL)
143 #define call_void_memop(vb, op, args...) \
145 if ((vb)->vb2_queue->mem_ops->op) \
146 (vb)->vb2_queue->mem_ops->op(args); \
149 #define call_qop(q, op, args...) \
150 ((q)->ops->op ? (q)->ops->op(args) : 0)
152 #define call_void_qop(q, op, args...) \
155 (q)->ops->op(args); \
158 #define call_vb_qop(vb, op, args...) \
159 ((vb)->vb2_queue->ops->op ? (vb)->vb2_queue->ops->op(args) : 0)
161 #define call_void_vb_qop(vb, op, args...) \
163 if ((vb)->vb2_queue->ops->op) \
164 (vb)->vb2_queue->ops->op(args); \
169 /* Flags that are set by the vb2 core */
170 #define V4L2_BUFFER_MASK_FLAGS (V4L2_BUF_FLAG_MAPPED | V4L2_BUF_FLAG_QUEUED | \
171 V4L2_BUF_FLAG_DONE | V4L2_BUF_FLAG_ERROR | \
172 V4L2_BUF_FLAG_PREPARED | \
173 V4L2_BUF_FLAG_TIMESTAMP_MASK)
174 /* Output buffer flags that should be passed on to the driver */
175 #define V4L2_BUFFER_OUT_FLAGS (V4L2_BUF_FLAG_PFRAME | V4L2_BUF_FLAG_BFRAME | \
176 V4L2_BUF_FLAG_KEYFRAME | V4L2_BUF_FLAG_TIMECODE)
178 static void __vb2_queue_cancel(struct vb2_queue *q);
181 * __vb2_buf_mem_alloc() - allocate video memory for the given buffer
183 static int __vb2_buf_mem_alloc(struct vb2_buffer *vb)
185 struct vb2_queue *q = vb->vb2_queue;
190 * Allocate memory for all planes in this buffer
191 * NOTE: mmapped areas should be page aligned
193 for (plane = 0; plane < vb->num_planes; ++plane) {
194 unsigned long size = PAGE_ALIGN(q->plane_sizes[plane]);
196 mem_priv = call_ptr_memop(vb, alloc, q->alloc_ctx[plane],
198 if (IS_ERR_OR_NULL(mem_priv))
201 /* Associate allocator private data with this plane */
202 vb->planes[plane].mem_priv = mem_priv;
203 vb->v4l2_planes[plane].length = q->plane_sizes[plane];
208 /* Free already allocated memory if one of the allocations failed */
209 for (; plane > 0; --plane) {
210 call_void_memop(vb, put, vb->planes[plane - 1].mem_priv);
211 vb->planes[plane - 1].mem_priv = NULL;
218 * __vb2_buf_mem_free() - free memory of the given buffer
220 static void __vb2_buf_mem_free(struct vb2_buffer *vb)
224 for (plane = 0; plane < vb->num_planes; ++plane) {
225 call_void_memop(vb, put, vb->planes[plane].mem_priv);
226 vb->planes[plane].mem_priv = NULL;
227 dprintk(3, "Freed plane %d of buffer %d\n", plane,
233 * __vb2_buf_userptr_put() - release userspace memory associated with
236 static void __vb2_buf_userptr_put(struct vb2_buffer *vb)
240 for (plane = 0; plane < vb->num_planes; ++plane) {
241 if (vb->planes[plane].mem_priv)
242 call_void_memop(vb, put_userptr, vb->planes[plane].mem_priv);
243 vb->planes[plane].mem_priv = NULL;
248 * __vb2_plane_dmabuf_put() - release memory associated with
249 * a DMABUF shared plane
251 static void __vb2_plane_dmabuf_put(struct vb2_buffer *vb, struct vb2_plane *p)
257 call_void_memop(vb, unmap_dmabuf, p->mem_priv);
259 call_void_memop(vb, detach_dmabuf, p->mem_priv);
260 dma_buf_put(p->dbuf);
261 memset(p, 0, sizeof(*p));
265 * __vb2_buf_dmabuf_put() - release memory associated with
266 * a DMABUF shared buffer
268 static void __vb2_buf_dmabuf_put(struct vb2_buffer *vb)
272 for (plane = 0; plane < vb->num_planes; ++plane)
273 __vb2_plane_dmabuf_put(vb, &vb->planes[plane]);
277 * __setup_lengths() - setup initial lengths for every plane in
278 * every buffer on the queue
280 static void __setup_lengths(struct vb2_queue *q, unsigned int n)
282 unsigned int buffer, plane;
283 struct vb2_buffer *vb;
285 for (buffer = q->num_buffers; buffer < q->num_buffers + n; ++buffer) {
286 vb = q->bufs[buffer];
290 for (plane = 0; plane < vb->num_planes; ++plane)
291 vb->v4l2_planes[plane].length = q->plane_sizes[plane];
296 * __setup_offsets() - setup unique offsets ("cookies") for every plane in
297 * every buffer on the queue
299 static void __setup_offsets(struct vb2_queue *q, unsigned int n)
301 unsigned int buffer, plane;
302 struct vb2_buffer *vb;
305 if (q->num_buffers) {
306 struct v4l2_plane *p;
307 vb = q->bufs[q->num_buffers - 1];
308 p = &vb->v4l2_planes[vb->num_planes - 1];
309 off = PAGE_ALIGN(p->m.mem_offset + p->length);
314 for (buffer = q->num_buffers; buffer < q->num_buffers + n; ++buffer) {
315 vb = q->bufs[buffer];
319 for (plane = 0; plane < vb->num_planes; ++plane) {
320 vb->v4l2_planes[plane].m.mem_offset = off;
322 dprintk(3, "Buffer %d, plane %d offset 0x%08lx\n",
325 off += vb->v4l2_planes[plane].length;
326 off = PAGE_ALIGN(off);
332 * __vb2_queue_alloc() - allocate videobuf buffer structures and (for MMAP type)
333 * video buffer memory for all buffers/planes on the queue and initializes the
336 * Returns the number of buffers successfully allocated.
338 static int __vb2_queue_alloc(struct vb2_queue *q, enum v4l2_memory memory,
339 unsigned int num_buffers, unsigned int num_planes)
342 struct vb2_buffer *vb;
345 for (buffer = 0; buffer < num_buffers; ++buffer) {
346 /* Allocate videobuf buffer structures */
347 vb = kzalloc(q->buf_struct_size, GFP_KERNEL);
349 dprintk(1, "Memory alloc for buffer struct failed\n");
353 /* Length stores number of planes for multiplanar buffers */
354 if (V4L2_TYPE_IS_MULTIPLANAR(q->type))
355 vb->v4l2_buf.length = num_planes;
357 vb->state = VB2_BUF_STATE_DEQUEUED;
359 vb->num_planes = num_planes;
360 vb->v4l2_buf.index = q->num_buffers + buffer;
361 vb->v4l2_buf.type = q->type;
362 vb->v4l2_buf.memory = memory;
364 /* Allocate video buffer memory for the MMAP type */
365 if (memory == V4L2_MEMORY_MMAP) {
366 ret = __vb2_buf_mem_alloc(vb);
368 dprintk(1, "Failed allocating memory for "
369 "buffer %d\n", buffer);
374 * Call the driver-provided buffer initialization
375 * callback, if given. An error in initialization
376 * results in queue setup failure.
378 ret = call_vb_qop(vb, buf_init, vb);
380 dprintk(1, "Buffer %d %p initialization"
381 " failed\n", buffer, vb);
382 __vb2_buf_mem_free(vb);
388 q->bufs[q->num_buffers + buffer] = vb;
391 __setup_lengths(q, buffer);
392 if (memory == V4L2_MEMORY_MMAP)
393 __setup_offsets(q, buffer);
395 dprintk(1, "Allocated %d buffers, %d plane(s) each\n",
402 * __vb2_free_mem() - release all video buffer memory for a given queue
404 static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers)
407 struct vb2_buffer *vb;
409 for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
411 vb = q->bufs[buffer];
415 /* Free MMAP buffers or release USERPTR buffers */
416 if (q->memory == V4L2_MEMORY_MMAP)
417 __vb2_buf_mem_free(vb);
418 else if (q->memory == V4L2_MEMORY_DMABUF)
419 __vb2_buf_dmabuf_put(vb);
421 __vb2_buf_userptr_put(vb);
426 * __vb2_queue_free() - free buffers at the end of the queue - video memory and
427 * related information, if no buffers are left return the queue to an
428 * uninitialized state. Might be called even if the queue has already been freed.
430 static int __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
435 * Sanity check: when preparing a buffer the queue lock is released for
436 * a short while (see __buf_prepare for the details), which would allow
437 * a race with a reqbufs which can call this function. Removing the
438 * buffers from underneath __buf_prepare is obviously a bad idea, so we
439 * check if any of the buffers is in the state PREPARING, and if so we
440 * just return -EAGAIN.
442 for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
444 if (q->bufs[buffer] == NULL)
446 if (q->bufs[buffer]->state == VB2_BUF_STATE_PREPARING) {
447 dprintk(1, "reqbufs: preparing buffers, cannot free\n");
452 /* Call driver-provided cleanup function for each buffer, if provided */
453 for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
455 struct vb2_buffer *vb = q->bufs[buffer];
457 if (vb && vb->planes[0].mem_priv)
458 call_void_vb_qop(vb, buf_cleanup, vb);
461 /* Release video buffer memory */
462 __vb2_free_mem(q, buffers);
464 #ifdef CONFIG_VIDEO_ADV_DEBUG
466 * Check that all the calls were balances during the life-time of this
467 * queue. If not (or if the debug level is 1 or up), then dump the
468 * counters to the kernel log.
470 if (q->num_buffers) {
471 bool unbalanced = q->cnt_start_streaming != q->cnt_stop_streaming ||
472 q->cnt_wait_prepare != q->cnt_wait_finish;
474 if (unbalanced || debug) {
475 pr_info("vb2: counters for queue %p:%s\n", q,
476 unbalanced ? " UNBALANCED!" : "");
477 pr_info("vb2: setup: %u start_streaming: %u stop_streaming: %u\n",
478 q->cnt_queue_setup, q->cnt_start_streaming,
479 q->cnt_stop_streaming);
480 pr_info("vb2: wait_prepare: %u wait_finish: %u\n",
481 q->cnt_wait_prepare, q->cnt_wait_finish);
483 q->cnt_queue_setup = 0;
484 q->cnt_wait_prepare = 0;
485 q->cnt_wait_finish = 0;
486 q->cnt_start_streaming = 0;
487 q->cnt_stop_streaming = 0;
489 for (buffer = 0; buffer < q->num_buffers; ++buffer) {
490 struct vb2_buffer *vb = q->bufs[buffer];
491 bool unbalanced = vb->cnt_mem_alloc != vb->cnt_mem_put ||
492 vb->cnt_mem_prepare != vb->cnt_mem_finish ||
493 vb->cnt_mem_get_userptr != vb->cnt_mem_put_userptr ||
494 vb->cnt_mem_attach_dmabuf != vb->cnt_mem_detach_dmabuf ||
495 vb->cnt_mem_map_dmabuf != vb->cnt_mem_unmap_dmabuf ||
496 vb->cnt_buf_queue != vb->cnt_buf_done ||
497 vb->cnt_buf_prepare != vb->cnt_buf_finish ||
498 vb->cnt_buf_init != vb->cnt_buf_cleanup;
500 if (unbalanced || debug) {
501 pr_info("vb2: counters for queue %p, buffer %d:%s\n",
502 q, buffer, unbalanced ? " UNBALANCED!" : "");
503 pr_info("vb2: buf_init: %u buf_cleanup: %u buf_prepare: %u buf_finish: %u\n",
504 vb->cnt_buf_init, vb->cnt_buf_cleanup,
505 vb->cnt_buf_prepare, vb->cnt_buf_finish);
506 pr_info("vb2: buf_queue: %u buf_done: %u\n",
507 vb->cnt_buf_queue, vb->cnt_buf_done);
508 pr_info("vb2: alloc: %u put: %u prepare: %u finish: %u mmap: %u\n",
509 vb->cnt_mem_alloc, vb->cnt_mem_put,
510 vb->cnt_mem_prepare, vb->cnt_mem_finish,
512 pr_info("vb2: get_userptr: %u put_userptr: %u\n",
513 vb->cnt_mem_get_userptr, vb->cnt_mem_put_userptr);
514 pr_info("vb2: attach_dmabuf: %u detach_dmabuf: %u map_dmabuf: %u unmap_dmabuf: %u\n",
515 vb->cnt_mem_attach_dmabuf, vb->cnt_mem_detach_dmabuf,
516 vb->cnt_mem_map_dmabuf, vb->cnt_mem_unmap_dmabuf);
517 pr_info("vb2: get_dmabuf: %u num_users: %u vaddr: %u cookie: %u\n",
518 vb->cnt_mem_get_dmabuf,
519 vb->cnt_mem_num_users,
526 /* Free videobuf buffers */
527 for (buffer = q->num_buffers - buffers; buffer < q->num_buffers;
529 kfree(q->bufs[buffer]);
530 q->bufs[buffer] = NULL;
533 q->num_buffers -= buffers;
534 if (!q->num_buffers) {
536 INIT_LIST_HEAD(&q->queued_list);
542 * __verify_planes_array() - verify that the planes array passed in struct
543 * v4l2_buffer from userspace can be safely used
545 static int __verify_planes_array(struct vb2_buffer *vb, const struct v4l2_buffer *b)
547 if (!V4L2_TYPE_IS_MULTIPLANAR(b->type))
550 /* Is memory for copying plane information present? */
551 if (NULL == b->m.planes) {
552 dprintk(1, "Multi-planar buffer passed but "
553 "planes array not provided\n");
557 if (b->length < vb->num_planes || b->length > VIDEO_MAX_PLANES) {
558 dprintk(1, "Incorrect planes array length, "
559 "expected %d, got %d\n", vb->num_planes, b->length);
567 * __verify_length() - Verify that the bytesused value for each plane fits in
568 * the plane length and that the data offset doesn't exceed the bytesused value.
570 static int __verify_length(struct vb2_buffer *vb, const struct v4l2_buffer *b)
575 if (!V4L2_TYPE_IS_OUTPUT(b->type))
578 if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) {
579 for (plane = 0; plane < vb->num_planes; ++plane) {
580 length = (b->memory == V4L2_MEMORY_USERPTR)
581 ? b->m.planes[plane].length
582 : vb->v4l2_planes[plane].length;
584 if (b->m.planes[plane].bytesused > length)
587 if (b->m.planes[plane].data_offset > 0 &&
588 b->m.planes[plane].data_offset >=
589 b->m.planes[plane].bytesused)
593 length = (b->memory == V4L2_MEMORY_USERPTR)
594 ? b->length : vb->v4l2_planes[0].length;
596 if (b->bytesused > length)
604 * __buffer_in_use() - return true if the buffer is in use and
605 * the queue cannot be freed (by the means of REQBUFS(0)) call
607 static bool __buffer_in_use(struct vb2_queue *q, struct vb2_buffer *vb)
610 for (plane = 0; plane < vb->num_planes; ++plane) {
611 void *mem_priv = vb->planes[plane].mem_priv;
613 * If num_users() has not been provided, call_memop
614 * will return 0, apparently nobody cares about this
615 * case anyway. If num_users() returns more than 1,
616 * we are not the only user of the plane's memory.
618 if (mem_priv && call_memop(vb, num_users, mem_priv) > 1)
625 * __buffers_in_use() - return true if any buffers on the queue are in use and
626 * the queue cannot be freed (by the means of REQBUFS(0)) call
628 static bool __buffers_in_use(struct vb2_queue *q)
631 for (buffer = 0; buffer < q->num_buffers; ++buffer) {
632 if (__buffer_in_use(q, q->bufs[buffer]))
639 * __fill_v4l2_buffer() - fill in a struct v4l2_buffer with information to be
640 * returned to userspace
642 static void __fill_v4l2_buffer(struct vb2_buffer *vb, struct v4l2_buffer *b)
644 struct vb2_queue *q = vb->vb2_queue;
646 /* Copy back data such as timestamp, flags, etc. */
647 memcpy(b, &vb->v4l2_buf, offsetof(struct v4l2_buffer, m));
648 b->reserved2 = vb->v4l2_buf.reserved2;
649 b->reserved = vb->v4l2_buf.reserved;
651 if (V4L2_TYPE_IS_MULTIPLANAR(q->type)) {
653 * Fill in plane-related data if userspace provided an array
654 * for it. The caller has already verified memory and size.
656 b->length = vb->num_planes;
657 memcpy(b->m.planes, vb->v4l2_planes,
658 b->length * sizeof(struct v4l2_plane));
661 * We use length and offset in v4l2_planes array even for
662 * single-planar buffers, but userspace does not.
664 b->length = vb->v4l2_planes[0].length;
665 b->bytesused = vb->v4l2_planes[0].bytesused;
666 if (q->memory == V4L2_MEMORY_MMAP)
667 b->m.offset = vb->v4l2_planes[0].m.mem_offset;
668 else if (q->memory == V4L2_MEMORY_USERPTR)
669 b->m.userptr = vb->v4l2_planes[0].m.userptr;
670 else if (q->memory == V4L2_MEMORY_DMABUF)
671 b->m.fd = vb->v4l2_planes[0].m.fd;
675 * Clear any buffer state related flags.
677 b->flags &= ~V4L2_BUFFER_MASK_FLAGS;
678 b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK;
679 if ((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) !=
680 V4L2_BUF_FLAG_TIMESTAMP_COPY) {
682 * For non-COPY timestamps, drop timestamp source bits
683 * and obtain the timestamp source from the queue.
685 b->flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
686 b->flags |= q->timestamp_flags & V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
690 case VB2_BUF_STATE_QUEUED:
691 case VB2_BUF_STATE_ACTIVE:
692 b->flags |= V4L2_BUF_FLAG_QUEUED;
694 case VB2_BUF_STATE_ERROR:
695 b->flags |= V4L2_BUF_FLAG_ERROR;
697 case VB2_BUF_STATE_DONE:
698 b->flags |= V4L2_BUF_FLAG_DONE;
700 case VB2_BUF_STATE_PREPARED:
701 b->flags |= V4L2_BUF_FLAG_PREPARED;
703 case VB2_BUF_STATE_PREPARING:
704 case VB2_BUF_STATE_DEQUEUED:
709 if (__buffer_in_use(q, vb))
710 b->flags |= V4L2_BUF_FLAG_MAPPED;
714 * vb2_querybuf() - query video buffer information
716 * @b: buffer struct passed from userspace to vidioc_querybuf handler
719 * Should be called from vidioc_querybuf ioctl handler in driver.
720 * This function will verify the passed v4l2_buffer structure and fill the
721 * relevant information for the userspace.
723 * The return values from this function are intended to be directly returned
724 * from vidioc_querybuf handler in driver.
726 int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b)
728 struct vb2_buffer *vb;
731 if (b->type != q->type) {
732 dprintk(1, "querybuf: wrong buffer type\n");
736 if (b->index >= q->num_buffers) {
737 dprintk(1, "querybuf: buffer index out of range\n");
740 vb = q->bufs[b->index];
741 ret = __verify_planes_array(vb, b);
743 __fill_v4l2_buffer(vb, b);
746 EXPORT_SYMBOL(vb2_querybuf);
749 * __verify_userptr_ops() - verify that all memory operations required for
750 * USERPTR queue type have been provided
752 static int __verify_userptr_ops(struct vb2_queue *q)
754 if (!(q->io_modes & VB2_USERPTR) || !q->mem_ops->get_userptr ||
755 !q->mem_ops->put_userptr)
762 * __verify_mmap_ops() - verify that all memory operations required for
763 * MMAP queue type have been provided
765 static int __verify_mmap_ops(struct vb2_queue *q)
767 if (!(q->io_modes & VB2_MMAP) || !q->mem_ops->alloc ||
768 !q->mem_ops->put || !q->mem_ops->mmap)
775 * __verify_dmabuf_ops() - verify that all memory operations required for
776 * DMABUF queue type have been provided
778 static int __verify_dmabuf_ops(struct vb2_queue *q)
780 if (!(q->io_modes & VB2_DMABUF) || !q->mem_ops->attach_dmabuf ||
781 !q->mem_ops->detach_dmabuf || !q->mem_ops->map_dmabuf ||
782 !q->mem_ops->unmap_dmabuf)
789 * __verify_memory_type() - Check whether the memory type and buffer type
790 * passed to a buffer operation are compatible with the queue.
792 static int __verify_memory_type(struct vb2_queue *q,
793 enum v4l2_memory memory, enum v4l2_buf_type type)
795 if (memory != V4L2_MEMORY_MMAP && memory != V4L2_MEMORY_USERPTR &&
796 memory != V4L2_MEMORY_DMABUF) {
797 dprintk(1, "reqbufs: unsupported memory type\n");
801 if (type != q->type) {
802 dprintk(1, "reqbufs: requested type is incorrect\n");
807 * Make sure all the required memory ops for given memory type
810 if (memory == V4L2_MEMORY_MMAP && __verify_mmap_ops(q)) {
811 dprintk(1, "reqbufs: MMAP for current setup unsupported\n");
815 if (memory == V4L2_MEMORY_USERPTR && __verify_userptr_ops(q)) {
816 dprintk(1, "reqbufs: USERPTR for current setup unsupported\n");
820 if (memory == V4L2_MEMORY_DMABUF && __verify_dmabuf_ops(q)) {
821 dprintk(1, "reqbufs: DMABUF for current setup unsupported\n");
826 * Place the busy tests at the end: -EBUSY can be ignored when
827 * create_bufs is called with count == 0, but count == 0 should still
828 * do the memory and type validation.
831 dprintk(1, "reqbufs: file io in progress\n");
838 * __reqbufs() - Initiate streaming
839 * @q: videobuf2 queue
840 * @req: struct passed from userspace to vidioc_reqbufs handler in driver
842 * Should be called from vidioc_reqbufs ioctl handler of a driver.
844 * 1) verifies streaming parameters passed from the userspace,
845 * 2) sets up the queue,
846 * 3) negotiates number of buffers and planes per buffer with the driver
847 * to be used during streaming,
848 * 4) allocates internal buffer structures (struct vb2_buffer), according to
849 * the agreed parameters,
850 * 5) for MMAP memory type, allocates actual video memory, using the
851 * memory handling/allocation routines provided during queue initialization
853 * If req->count is 0, all the memory will be freed instead.
854 * If the queue has been allocated previously (by a previous vb2_reqbufs) call
855 * and the queue is not busy, memory will be reallocated.
857 * The return values from this function are intended to be directly returned
858 * from vidioc_reqbufs handler in driver.
860 static int __reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
862 unsigned int num_buffers, allocated_buffers, num_planes = 0;
866 dprintk(1, "reqbufs: streaming active\n");
870 if (req->count == 0 || q->num_buffers != 0 || q->memory != req->memory) {
872 * We already have buffers allocated, so first check if they
873 * are not in use and can be freed.
875 if (q->memory == V4L2_MEMORY_MMAP && __buffers_in_use(q)) {
876 dprintk(1, "reqbufs: memory in use, cannot free\n");
881 * Call queue_cancel to clean up any buffers in the PREPARED or
882 * QUEUED state which is possible if buffers were prepared or
883 * queued without ever calling STREAMON.
885 __vb2_queue_cancel(q);
886 ret = __vb2_queue_free(q, q->num_buffers);
891 * In case of REQBUFS(0) return immediately without calling
892 * driver's queue_setup() callback and allocating resources.
899 * Make sure the requested values and current defaults are sane.
901 num_buffers = min_t(unsigned int, req->count, VIDEO_MAX_FRAME);
902 num_buffers = max_t(unsigned int, req->count, q->min_buffers_needed);
903 memset(q->plane_sizes, 0, sizeof(q->plane_sizes));
904 memset(q->alloc_ctx, 0, sizeof(q->alloc_ctx));
905 q->memory = req->memory;
908 * Ask the driver how many buffers and planes per buffer it requires.
909 * Driver also sets the size and allocator context for each plane.
911 ret = call_qop(q, queue_setup, q, NULL, &num_buffers, &num_planes,
912 q->plane_sizes, q->alloc_ctx);
916 /* Finally, allocate buffers and video memory */
917 allocated_buffers = __vb2_queue_alloc(q, req->memory, num_buffers, num_planes);
918 if (allocated_buffers == 0) {
919 dprintk(1, "Memory allocation failed\n");
924 * There is no point in continuing if we can't allocate the minimum
925 * number of buffers needed by this vb2_queue.
927 if (allocated_buffers < q->min_buffers_needed)
931 * Check if driver can handle the allocated number of buffers.
933 if (!ret && allocated_buffers < num_buffers) {
934 num_buffers = allocated_buffers;
936 ret = call_qop(q, queue_setup, q, NULL, &num_buffers,
937 &num_planes, q->plane_sizes, q->alloc_ctx);
939 if (!ret && allocated_buffers < num_buffers)
943 * Either the driver has accepted a smaller number of buffers,
944 * or .queue_setup() returned an error
948 q->num_buffers = allocated_buffers;
952 * Note: __vb2_queue_free() will subtract 'allocated_buffers'
953 * from q->num_buffers.
955 __vb2_queue_free(q, allocated_buffers);
960 * Return the number of successfully allocated buffers
963 req->count = allocated_buffers;
969 * vb2_reqbufs() - Wrapper for __reqbufs() that also verifies the memory and
971 * @q: videobuf2 queue
972 * @req: struct passed from userspace to vidioc_reqbufs handler in driver
974 int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
976 int ret = __verify_memory_type(q, req->memory, req->type);
978 return ret ? ret : __reqbufs(q, req);
980 EXPORT_SYMBOL_GPL(vb2_reqbufs);
983 * __create_bufs() - Allocate buffers and any required auxiliary structs
984 * @q: videobuf2 queue
985 * @create: creation parameters, passed from userspace to vidioc_create_bufs
988 * Should be called from vidioc_create_bufs ioctl handler of a driver.
990 * 1) verifies parameter sanity
991 * 2) calls the .queue_setup() queue operation
992 * 3) performs any necessary memory allocations
994 * The return values from this function are intended to be directly returned
995 * from vidioc_create_bufs handler in driver.
997 static int __create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create)
999 unsigned int num_planes = 0, num_buffers, allocated_buffers;
1002 if (q->num_buffers == VIDEO_MAX_FRAME) {
1003 dprintk(1, "%s(): maximum number of buffers already allocated\n",
1008 if (!q->num_buffers) {
1009 memset(q->plane_sizes, 0, sizeof(q->plane_sizes));
1010 memset(q->alloc_ctx, 0, sizeof(q->alloc_ctx));
1011 q->memory = create->memory;
1014 num_buffers = min(create->count, VIDEO_MAX_FRAME - q->num_buffers);
1017 * Ask the driver, whether the requested number of buffers, planes per
1018 * buffer and their sizes are acceptable
1020 ret = call_qop(q, queue_setup, q, &create->format, &num_buffers,
1021 &num_planes, q->plane_sizes, q->alloc_ctx);
1025 /* Finally, allocate buffers and video memory */
1026 allocated_buffers = __vb2_queue_alloc(q, create->memory, num_buffers,
1028 if (allocated_buffers == 0) {
1029 dprintk(1, "Memory allocation failed\n");
1034 * Check if driver can handle the so far allocated number of buffers.
1036 if (allocated_buffers < num_buffers) {
1037 num_buffers = allocated_buffers;
1040 * q->num_buffers contains the total number of buffers, that the
1041 * queue driver has set up
1043 ret = call_qop(q, queue_setup, q, &create->format, &num_buffers,
1044 &num_planes, q->plane_sizes, q->alloc_ctx);
1046 if (!ret && allocated_buffers < num_buffers)
1050 * Either the driver has accepted a smaller number of buffers,
1051 * or .queue_setup() returned an error
1055 q->num_buffers += allocated_buffers;
1059 * Note: __vb2_queue_free() will subtract 'allocated_buffers'
1060 * from q->num_buffers.
1062 __vb2_queue_free(q, allocated_buffers);
1067 * Return the number of successfully allocated buffers
1070 create->count = allocated_buffers;
1076 * vb2_create_bufs() - Wrapper for __create_bufs() that also verifies the
1077 * memory and type values.
1078 * @q: videobuf2 queue
1079 * @create: creation parameters, passed from userspace to vidioc_create_bufs
1082 int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create)
1084 int ret = __verify_memory_type(q, create->memory, create->format.type);
1086 create->index = q->num_buffers;
1087 if (create->count == 0)
1088 return ret != -EBUSY ? ret : 0;
1089 return ret ? ret : __create_bufs(q, create);
1091 EXPORT_SYMBOL_GPL(vb2_create_bufs);
1094 * vb2_plane_vaddr() - Return a kernel virtual address of a given plane
1095 * @vb: vb2_buffer to which the plane in question belongs to
1096 * @plane_no: plane number for which the address is to be returned
1098 * This function returns a kernel virtual address of a given plane if
1099 * such a mapping exist, NULL otherwise.
1101 void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no)
1103 if (plane_no > vb->num_planes || !vb->planes[plane_no].mem_priv)
1106 return call_ptr_memop(vb, vaddr, vb->planes[plane_no].mem_priv);
1109 EXPORT_SYMBOL_GPL(vb2_plane_vaddr);
1112 * vb2_plane_cookie() - Return allocator specific cookie for the given plane
1113 * @vb: vb2_buffer to which the plane in question belongs to
1114 * @plane_no: plane number for which the cookie is to be returned
1116 * This function returns an allocator specific cookie for a given plane if
1117 * available, NULL otherwise. The allocator should provide some simple static
1118 * inline function, which would convert this cookie to the allocator specific
1119 * type that can be used directly by the driver to access the buffer. This can
1120 * be for example physical address, pointer to scatter list or IOMMU mapping.
1122 void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no)
1124 if (plane_no > vb->num_planes || !vb->planes[plane_no].mem_priv)
1127 return call_ptr_memop(vb, cookie, vb->planes[plane_no].mem_priv);
1129 EXPORT_SYMBOL_GPL(vb2_plane_cookie);
1132 * vb2_buffer_done() - inform videobuf that an operation on a buffer is finished
1133 * @vb: vb2_buffer returned from the driver
1134 * @state: either VB2_BUF_STATE_DONE if the operation finished successfully
1135 * or VB2_BUF_STATE_ERROR if the operation finished with an error.
1136 * If start_streaming fails then it should return buffers with state
1137 * VB2_BUF_STATE_QUEUED to put them back into the queue.
1139 * This function should be called by the driver after a hardware operation on
1140 * a buffer is finished and the buffer may be returned to userspace. The driver
1141 * cannot use this buffer anymore until it is queued back to it by videobuf
1142 * by the means of buf_queue callback. Only buffers previously queued to the
1143 * driver by buf_queue can be passed to this function.
1145 * While streaming a buffer can only be returned in state DONE or ERROR.
1146 * The start_streaming op can also return them in case the DMA engine cannot
1147 * be started for some reason. In that case the buffers should be returned with
1150 void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state)
1152 struct vb2_queue *q = vb->vb2_queue;
1153 unsigned long flags;
1156 if (WARN_ON(vb->state != VB2_BUF_STATE_ACTIVE))
1159 if (!q->start_streaming_called) {
1160 if (WARN_ON(state != VB2_BUF_STATE_QUEUED))
1161 state = VB2_BUF_STATE_QUEUED;
1162 } else if (!WARN_ON(!q->start_streaming_called)) {
1163 if (WARN_ON(state != VB2_BUF_STATE_DONE &&
1164 state != VB2_BUF_STATE_ERROR))
1165 state = VB2_BUF_STATE_ERROR;
1168 #ifdef CONFIG_VIDEO_ADV_DEBUG
1170 * Although this is not a callback, it still does have to balance
1171 * with the buf_queue op. So update this counter manually.
1175 dprintk(4, "Done processing on buffer %d, state: %d\n",
1176 vb->v4l2_buf.index, state);
1179 for (plane = 0; plane < vb->num_planes; ++plane)
1180 call_void_memop(vb, finish, vb->planes[plane].mem_priv);
1182 /* Add the buffer to the done buffers list */
1183 spin_lock_irqsave(&q->done_lock, flags);
1185 if (state != VB2_BUF_STATE_QUEUED)
1186 list_add_tail(&vb->done_entry, &q->done_list);
1187 atomic_dec(&q->owned_by_drv_count);
1188 spin_unlock_irqrestore(&q->done_lock, flags);
1190 if (state == VB2_BUF_STATE_QUEUED)
1193 /* Inform any processes that may be waiting for buffers */
1194 wake_up(&q->done_wq);
1196 EXPORT_SYMBOL_GPL(vb2_buffer_done);
1199 * __fill_vb2_buffer() - fill a vb2_buffer with information provided in a
1200 * v4l2_buffer by the userspace. The caller has already verified that struct
1201 * v4l2_buffer has a valid number of planes.
1203 static void __fill_vb2_buffer(struct vb2_buffer *vb, const struct v4l2_buffer *b,
1204 struct v4l2_plane *v4l2_planes)
1208 if (V4L2_TYPE_IS_MULTIPLANAR(b->type)) {
1209 /* Fill in driver-provided information for OUTPUT types */
1210 if (V4L2_TYPE_IS_OUTPUT(b->type)) {
1212 * Will have to go up to b->length when API starts
1213 * accepting variable number of planes.
1215 for (plane = 0; plane < vb->num_planes; ++plane) {
1216 v4l2_planes[plane].bytesused =
1217 b->m.planes[plane].bytesused;
1218 v4l2_planes[plane].data_offset =
1219 b->m.planes[plane].data_offset;
1223 if (b->memory == V4L2_MEMORY_USERPTR) {
1224 for (plane = 0; plane < vb->num_planes; ++plane) {
1225 v4l2_planes[plane].m.userptr =
1226 b->m.planes[plane].m.userptr;
1227 v4l2_planes[plane].length =
1228 b->m.planes[plane].length;
1231 if (b->memory == V4L2_MEMORY_DMABUF) {
1232 for (plane = 0; plane < vb->num_planes; ++plane) {
1233 v4l2_planes[plane].m.fd =
1234 b->m.planes[plane].m.fd;
1235 v4l2_planes[plane].length =
1236 b->m.planes[plane].length;
1237 v4l2_planes[plane].data_offset =
1238 b->m.planes[plane].data_offset;
1243 * Single-planar buffers do not use planes array,
1244 * so fill in relevant v4l2_buffer struct fields instead.
1245 * In videobuf we use our internal V4l2_planes struct for
1246 * single-planar buffers as well, for simplicity.
1248 if (V4L2_TYPE_IS_OUTPUT(b->type)) {
1249 v4l2_planes[0].bytesused = b->bytesused;
1250 v4l2_planes[0].data_offset = 0;
1253 if (b->memory == V4L2_MEMORY_USERPTR) {
1254 v4l2_planes[0].m.userptr = b->m.userptr;
1255 v4l2_planes[0].length = b->length;
1258 if (b->memory == V4L2_MEMORY_DMABUF) {
1259 v4l2_planes[0].m.fd = b->m.fd;
1260 v4l2_planes[0].length = b->length;
1261 v4l2_planes[0].data_offset = 0;
1266 /* Zero flags that the vb2 core handles */
1267 vb->v4l2_buf.flags = b->flags & ~V4L2_BUFFER_MASK_FLAGS;
1268 if ((vb->vb2_queue->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) !=
1269 V4L2_BUF_FLAG_TIMESTAMP_COPY || !V4L2_TYPE_IS_OUTPUT(b->type)) {
1271 * Non-COPY timestamps and non-OUTPUT queues will get
1272 * their timestamp and timestamp source flags from the
1275 vb->v4l2_buf.flags &= ~V4L2_BUF_FLAG_TSTAMP_SRC_MASK;
1278 if (V4L2_TYPE_IS_OUTPUT(b->type)) {
1280 * For output buffers mask out the timecode flag:
1281 * this will be handled later in vb2_internal_qbuf().
1282 * The 'field' is valid metadata for this output buffer
1283 * and so that needs to be copied here.
1285 vb->v4l2_buf.flags &= ~V4L2_BUF_FLAG_TIMECODE;
1286 vb->v4l2_buf.field = b->field;
1288 /* Zero any output buffer flags as this is a capture buffer */
1289 vb->v4l2_buf.flags &= ~V4L2_BUFFER_OUT_FLAGS;
1294 * __qbuf_userptr() - handle qbuf of a USERPTR buffer
1296 static int __qbuf_userptr(struct vb2_buffer *vb, const struct v4l2_buffer *b)
1298 struct v4l2_plane planes[VIDEO_MAX_PLANES];
1299 struct vb2_queue *q = vb->vb2_queue;
1303 int write = !V4L2_TYPE_IS_OUTPUT(q->type);
1304 bool reacquired = vb->planes[0].mem_priv == NULL;
1306 /* Copy relevant information provided by the userspace */
1307 __fill_vb2_buffer(vb, b, planes);
1309 for (plane = 0; plane < vb->num_planes; ++plane) {
1310 /* Skip the plane if already verified */
1311 if (vb->v4l2_planes[plane].m.userptr &&
1312 vb->v4l2_planes[plane].m.userptr == planes[plane].m.userptr
1313 && vb->v4l2_planes[plane].length == planes[plane].length)
1316 dprintk(3, "qbuf: userspace address for plane %d changed, "
1317 "reacquiring memory\n", plane);
1319 /* Check if the provided plane buffer is large enough */
1320 if (planes[plane].length < q->plane_sizes[plane]) {
1321 dprintk(1, "qbuf: provided buffer size %u is less than "
1322 "setup size %u for plane %d\n",
1323 planes[plane].length,
1324 q->plane_sizes[plane], plane);
1329 /* Release previously acquired memory if present */
1330 if (vb->planes[plane].mem_priv) {
1333 call_void_vb_qop(vb, buf_cleanup, vb);
1335 call_void_memop(vb, put_userptr, vb->planes[plane].mem_priv);
1338 vb->planes[plane].mem_priv = NULL;
1339 memset(&vb->v4l2_planes[plane], 0, sizeof(struct v4l2_plane));
1341 /* Acquire each plane's memory */
1342 mem_priv = call_ptr_memop(vb, get_userptr, q->alloc_ctx[plane],
1343 planes[plane].m.userptr,
1344 planes[plane].length, write);
1345 if (IS_ERR_OR_NULL(mem_priv)) {
1346 dprintk(1, "qbuf: failed acquiring userspace "
1347 "memory for plane %d\n", plane);
1348 ret = mem_priv ? PTR_ERR(mem_priv) : -EINVAL;
1351 vb->planes[plane].mem_priv = mem_priv;
1355 * Now that everything is in order, copy relevant information
1356 * provided by userspace.
1358 for (plane = 0; plane < vb->num_planes; ++plane)
1359 vb->v4l2_planes[plane] = planes[plane];
1363 * One or more planes changed, so we must call buf_init to do
1364 * the driver-specific initialization on the newly acquired
1365 * buffer, if provided.
1367 ret = call_vb_qop(vb, buf_init, vb);
1369 dprintk(1, "qbuf: buffer initialization failed\n");
1374 ret = call_vb_qop(vb, buf_prepare, vb);
1376 dprintk(1, "qbuf: buffer preparation failed\n");
1377 call_void_vb_qop(vb, buf_cleanup, vb);
1383 /* In case of errors, release planes that were already acquired */
1384 for (plane = 0; plane < vb->num_planes; ++plane) {
1385 if (vb->planes[plane].mem_priv)
1386 call_void_memop(vb, put_userptr, vb->planes[plane].mem_priv);
1387 vb->planes[plane].mem_priv = NULL;
1388 vb->v4l2_planes[plane].m.userptr = 0;
1389 vb->v4l2_planes[plane].length = 0;
1396 * __qbuf_mmap() - handle qbuf of an MMAP buffer
1398 static int __qbuf_mmap(struct vb2_buffer *vb, const struct v4l2_buffer *b)
1400 __fill_vb2_buffer(vb, b, vb->v4l2_planes);
1401 return call_vb_qop(vb, buf_prepare, vb);
1405 * __qbuf_dmabuf() - handle qbuf of a DMABUF buffer
1407 static int __qbuf_dmabuf(struct vb2_buffer *vb, const struct v4l2_buffer *b)
1409 struct v4l2_plane planes[VIDEO_MAX_PLANES];
1410 struct vb2_queue *q = vb->vb2_queue;
1414 int write = !V4L2_TYPE_IS_OUTPUT(q->type);
1415 bool reacquired = vb->planes[0].mem_priv == NULL;
1417 /* Copy relevant information provided by the userspace */
1418 __fill_vb2_buffer(vb, b, planes);
1420 for (plane = 0; plane < vb->num_planes; ++plane) {
1421 struct dma_buf *dbuf = dma_buf_get(planes[plane].m.fd);
1423 if (IS_ERR_OR_NULL(dbuf)) {
1424 dprintk(1, "qbuf: invalid dmabuf fd for plane %d\n",
1430 /* use DMABUF size if length is not provided */
1431 if (planes[plane].length == 0)
1432 planes[plane].length = dbuf->size;
1434 if (planes[plane].length < planes[plane].data_offset +
1435 q->plane_sizes[plane]) {
1436 dprintk(1, "qbuf: invalid dmabuf length for plane %d\n",
1442 /* Skip the plane if already verified */
1443 if (dbuf == vb->planes[plane].dbuf &&
1444 vb->v4l2_planes[plane].length == planes[plane].length) {
1449 dprintk(1, "qbuf: buffer for plane %d changed\n", plane);
1453 call_void_vb_qop(vb, buf_cleanup, vb);
1456 /* Release previously acquired memory if present */
1457 __vb2_plane_dmabuf_put(vb, &vb->planes[plane]);
1458 memset(&vb->v4l2_planes[plane], 0, sizeof(struct v4l2_plane));
1460 /* Acquire each plane's memory */
1461 mem_priv = call_ptr_memop(vb, attach_dmabuf, q->alloc_ctx[plane],
1462 dbuf, planes[plane].length, write);
1463 if (IS_ERR(mem_priv)) {
1464 dprintk(1, "qbuf: failed to attach dmabuf\n");
1465 ret = PTR_ERR(mem_priv);
1470 vb->planes[plane].dbuf = dbuf;
1471 vb->planes[plane].mem_priv = mem_priv;
1474 /* TODO: This pins the buffer(s) with dma_buf_map_attachment()).. but
1475 * really we want to do this just before the DMA, not while queueing
1478 for (plane = 0; plane < vb->num_planes; ++plane) {
1479 ret = call_memop(vb, map_dmabuf, vb->planes[plane].mem_priv);
1481 dprintk(1, "qbuf: failed to map dmabuf for plane %d\n",
1485 vb->planes[plane].dbuf_mapped = 1;
1489 * Now that everything is in order, copy relevant information
1490 * provided by userspace.
1492 for (plane = 0; plane < vb->num_planes; ++plane)
1493 vb->v4l2_planes[plane] = planes[plane];
1497 * Call driver-specific initialization on the newly acquired buffer,
1500 ret = call_vb_qop(vb, buf_init, vb);
1502 dprintk(1, "qbuf: buffer initialization failed\n");
1507 ret = call_vb_qop(vb, buf_prepare, vb);
1509 dprintk(1, "qbuf: buffer preparation failed\n");
1510 call_void_vb_qop(vb, buf_cleanup, vb);
1516 /* In case of errors, release planes that were already acquired */
1517 __vb2_buf_dmabuf_put(vb);
1523 * __enqueue_in_driver() - enqueue a vb2_buffer in driver for processing
1525 static void __enqueue_in_driver(struct vb2_buffer *vb)
1527 struct vb2_queue *q = vb->vb2_queue;
1530 vb->state = VB2_BUF_STATE_ACTIVE;
1531 atomic_inc(&q->owned_by_drv_count);
1534 for (plane = 0; plane < vb->num_planes; ++plane)
1535 call_void_memop(vb, prepare, vb->planes[plane].mem_priv);
1537 call_void_vb_qop(vb, buf_queue, vb);
1540 static int __buf_prepare(struct vb2_buffer *vb, const struct v4l2_buffer *b)
1542 struct vb2_queue *q = vb->vb2_queue;
1543 struct rw_semaphore *mmap_sem;
1546 ret = __verify_length(vb, b);
1548 dprintk(1, "%s(): plane parameters verification failed: %d\n",
1553 vb->state = VB2_BUF_STATE_PREPARING;
1554 vb->v4l2_buf.timestamp.tv_sec = 0;
1555 vb->v4l2_buf.timestamp.tv_usec = 0;
1556 vb->v4l2_buf.sequence = 0;
1558 switch (q->memory) {
1559 case V4L2_MEMORY_MMAP:
1560 ret = __qbuf_mmap(vb, b);
1562 case V4L2_MEMORY_USERPTR:
1564 * In case of user pointer buffers vb2 allocators need to get
1565 * direct access to userspace pages. This requires getting
1566 * the mmap semaphore for read access in the current process
1567 * structure. The same semaphore is taken before calling mmap
1568 * operation, while both qbuf/prepare_buf and mmap are called
1569 * by the driver or v4l2 core with the driver's lock held.
1570 * To avoid an AB-BA deadlock (mmap_sem then driver's lock in
1571 * mmap and driver's lock then mmap_sem in qbuf/prepare_buf),
1572 * the videobuf2 core releases the driver's lock, takes
1573 * mmap_sem and then takes the driver's lock again.
1575 mmap_sem = ¤t->mm->mmap_sem;
1576 call_void_qop(q, wait_prepare, q);
1577 down_read(mmap_sem);
1578 call_void_qop(q, wait_finish, q);
1580 ret = __qbuf_userptr(vb, b);
1584 case V4L2_MEMORY_DMABUF:
1585 ret = __qbuf_dmabuf(vb, b);
1588 WARN(1, "Invalid queue type\n");
1593 dprintk(1, "qbuf: buffer preparation failed: %d\n", ret);
1594 vb->state = ret ? VB2_BUF_STATE_DEQUEUED : VB2_BUF_STATE_PREPARED;
1599 static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b,
1602 if (b->type != q->type) {
1603 dprintk(1, "%s(): invalid buffer type\n", opname);
1607 if (b->index >= q->num_buffers) {
1608 dprintk(1, "%s(): buffer index out of range\n", opname);
1612 if (q->bufs[b->index] == NULL) {
1613 /* Should never happen */
1614 dprintk(1, "%s(): buffer is NULL\n", opname);
1618 if (b->memory != q->memory) {
1619 dprintk(1, "%s(): invalid memory type\n", opname);
1623 return __verify_planes_array(q->bufs[b->index], b);
1627 * vb2_prepare_buf() - Pass ownership of a buffer from userspace to the kernel
1628 * @q: videobuf2 queue
1629 * @b: buffer structure passed from userspace to vidioc_prepare_buf
1632 * Should be called from vidioc_prepare_buf ioctl handler of a driver.
1634 * 1) verifies the passed buffer,
1635 * 2) calls buf_prepare callback in the driver (if provided), in which
1636 * driver-specific buffer initialization can be performed,
1638 * The return values from this function are intended to be directly returned
1639 * from vidioc_prepare_buf handler in driver.
1641 int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b)
1643 struct vb2_buffer *vb;
1647 dprintk(1, "%s(): file io in progress\n", __func__);
1651 ret = vb2_queue_or_prepare_buf(q, b, "prepare_buf");
1655 vb = q->bufs[b->index];
1656 if (vb->state != VB2_BUF_STATE_DEQUEUED) {
1657 dprintk(1, "%s(): invalid buffer state %d\n", __func__,
1662 ret = __buf_prepare(vb, b);
1664 /* Fill buffer information for the userspace */
1665 __fill_v4l2_buffer(vb, b);
1667 dprintk(1, "%s() of buffer %d succeeded\n", __func__, vb->v4l2_buf.index);
1671 EXPORT_SYMBOL_GPL(vb2_prepare_buf);
1674 * vb2_start_streaming() - Attempt to start streaming.
1675 * @q: videobuf2 queue
1677 * Attempt to start streaming. When this function is called there must be
1678 * at least q->min_buffers_needed buffers queued up (i.e. the minimum
1679 * number of buffers required for the DMA engine to function). If the
1680 * @start_streaming op fails it is supposed to return all the driver-owned
1681 * buffers back to vb2 in state QUEUED. Check if that happened and if
1682 * not warn and reclaim them forcefully.
1684 static int vb2_start_streaming(struct vb2_queue *q)
1686 struct vb2_buffer *vb;
1690 * If any buffers were queued before streamon,
1691 * we can now pass them to driver for processing.
1693 list_for_each_entry(vb, &q->queued_list, queued_entry)
1694 __enqueue_in_driver(vb);
1696 /* Tell the driver to start streaming */
1697 ret = call_qop(q, start_streaming, q,
1698 atomic_read(&q->owned_by_drv_count));
1699 q->start_streaming_called = ret == 0;
1703 dprintk(1, "qbuf: driver refused to start streaming\n");
1704 if (WARN_ON(atomic_read(&q->owned_by_drv_count))) {
1708 * Forcefully reclaim buffers if the driver did not
1709 * correctly return them to vb2.
1711 for (i = 0; i < q->num_buffers; ++i) {
1713 if (vb->state == VB2_BUF_STATE_ACTIVE)
1714 vb2_buffer_done(vb, VB2_BUF_STATE_QUEUED);
1716 /* Must be zero now */
1717 WARN_ON(atomic_read(&q->owned_by_drv_count));
1722 static int vb2_internal_qbuf(struct vb2_queue *q, struct v4l2_buffer *b)
1724 int ret = vb2_queue_or_prepare_buf(q, b, "qbuf");
1725 struct vb2_buffer *vb;
1730 vb = q->bufs[b->index];
1732 switch (vb->state) {
1733 case VB2_BUF_STATE_DEQUEUED:
1734 ret = __buf_prepare(vb, b);
1738 case VB2_BUF_STATE_PREPARED:
1740 case VB2_BUF_STATE_PREPARING:
1741 dprintk(1, "qbuf: buffer still being prepared\n");
1744 dprintk(1, "%s(): invalid buffer state %d\n", __func__,
1750 * Add to the queued buffers list, a buffer will stay on it until
1751 * dequeued in dqbuf.
1753 list_add_tail(&vb->queued_entry, &q->queued_list);
1755 vb->state = VB2_BUF_STATE_QUEUED;
1756 if (V4L2_TYPE_IS_OUTPUT(q->type)) {
1758 * For output buffers copy the timestamp if needed,
1759 * and the timecode field and flag if needed.
1761 if ((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) ==
1762 V4L2_BUF_FLAG_TIMESTAMP_COPY)
1763 vb->v4l2_buf.timestamp = b->timestamp;
1764 vb->v4l2_buf.flags |= b->flags & V4L2_BUF_FLAG_TIMECODE;
1765 if (b->flags & V4L2_BUF_FLAG_TIMECODE)
1766 vb->v4l2_buf.timecode = b->timecode;
1770 * If already streaming, give the buffer to driver for processing.
1771 * If not, the buffer will be given to driver on next streamon.
1773 if (q->start_streaming_called)
1774 __enqueue_in_driver(vb);
1776 /* Fill buffer information for the userspace */
1777 __fill_v4l2_buffer(vb, b);
1780 * If streamon has been called, and we haven't yet called
1781 * start_streaming() since not enough buffers were queued, and
1782 * we now have reached the minimum number of queued buffers,
1783 * then we can finally call start_streaming().
1785 if (q->streaming && !q->start_streaming_called &&
1786 q->queued_count >= q->min_buffers_needed) {
1787 ret = vb2_start_streaming(q);
1792 dprintk(1, "%s() of buffer %d succeeded\n", __func__, vb->v4l2_buf.index);
1797 * vb2_qbuf() - Queue a buffer from userspace
1798 * @q: videobuf2 queue
1799 * @b: buffer structure passed from userspace to vidioc_qbuf handler
1802 * Should be called from vidioc_qbuf ioctl handler of a driver.
1804 * 1) verifies the passed buffer,
1805 * 2) if necessary, calls buf_prepare callback in the driver (if provided), in
1806 * which driver-specific buffer initialization can be performed,
1807 * 3) if streaming is on, queues the buffer in driver by the means of buf_queue
1808 * callback for processing.
1810 * The return values from this function are intended to be directly returned
1811 * from vidioc_qbuf handler in driver.
1813 int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b)
1816 dprintk(1, "%s(): file io in progress\n", __func__);
1820 return vb2_internal_qbuf(q, b);
1822 EXPORT_SYMBOL_GPL(vb2_qbuf);
1825 * __vb2_wait_for_done_vb() - wait for a buffer to become available
1828 * Will sleep if required for nonblocking == false.
1830 static int __vb2_wait_for_done_vb(struct vb2_queue *q, int nonblocking)
1833 * All operations on vb_done_list are performed under done_lock
1834 * spinlock protection. However, buffers may be removed from
1835 * it and returned to userspace only while holding both driver's
1836 * lock and the done_lock spinlock. Thus we can be sure that as
1837 * long as we hold the driver's lock, the list will remain not
1838 * empty if list_empty() check succeeds.
1844 if (!q->streaming) {
1845 dprintk(1, "Streaming off, will not wait for buffers\n");
1849 if (!list_empty(&q->done_list)) {
1851 * Found a buffer that we were waiting for.
1857 dprintk(1, "Nonblocking and no buffers to dequeue, "
1863 * We are streaming and blocking, wait for another buffer to
1864 * become ready or for streamoff. Driver's lock is released to
1865 * allow streamoff or qbuf to be called while waiting.
1867 call_void_qop(q, wait_prepare, q);
1870 * All locks have been released, it is safe to sleep now.
1872 dprintk(3, "Will sleep waiting for buffers\n");
1873 ret = wait_event_interruptible(q->done_wq,
1874 !list_empty(&q->done_list) || !q->streaming);
1877 * We need to reevaluate both conditions again after reacquiring
1878 * the locks or return an error if one occurred.
1880 call_void_qop(q, wait_finish, q);
1882 dprintk(1, "Sleep was interrupted\n");
1890 * __vb2_get_done_vb() - get a buffer ready for dequeuing
1892 * Will sleep if required for nonblocking == false.
1894 static int __vb2_get_done_vb(struct vb2_queue *q, struct vb2_buffer **vb,
1895 struct v4l2_buffer *b, int nonblocking)
1897 unsigned long flags;
1901 * Wait for at least one buffer to become available on the done_list.
1903 ret = __vb2_wait_for_done_vb(q, nonblocking);
1908 * Driver's lock has been held since we last verified that done_list
1909 * is not empty, so no need for another list_empty(done_list) check.
1911 spin_lock_irqsave(&q->done_lock, flags);
1912 *vb = list_first_entry(&q->done_list, struct vb2_buffer, done_entry);
1914 * Only remove the buffer from done_list if v4l2_buffer can handle all
1917 ret = __verify_planes_array(*vb, b);
1919 list_del(&(*vb)->done_entry);
1920 spin_unlock_irqrestore(&q->done_lock, flags);
1926 * vb2_wait_for_all_buffers() - wait until all buffers are given back to vb2
1927 * @q: videobuf2 queue
1929 * This function will wait until all buffers that have been given to the driver
1930 * by buf_queue() are given back to vb2 with vb2_buffer_done(). It doesn't call
1931 * wait_prepare, wait_finish pair. It is intended to be called with all locks
1932 * taken, for example from stop_streaming() callback.
1934 int vb2_wait_for_all_buffers(struct vb2_queue *q)
1936 if (!q->streaming) {
1937 dprintk(1, "Streaming off, will not wait for buffers\n");
1941 if (q->start_streaming_called)
1942 wait_event(q->done_wq, !atomic_read(&q->owned_by_drv_count));
1945 EXPORT_SYMBOL_GPL(vb2_wait_for_all_buffers);
1948 * __vb2_dqbuf() - bring back the buffer to the DEQUEUED state
1950 static void __vb2_dqbuf(struct vb2_buffer *vb)
1952 struct vb2_queue *q = vb->vb2_queue;
1955 /* nothing to do if the buffer is already dequeued */
1956 if (vb->state == VB2_BUF_STATE_DEQUEUED)
1959 vb->state = VB2_BUF_STATE_DEQUEUED;
1961 /* unmap DMABUF buffer */
1962 if (q->memory == V4L2_MEMORY_DMABUF)
1963 for (i = 0; i < vb->num_planes; ++i) {
1964 if (!vb->planes[i].dbuf_mapped)
1966 call_void_memop(vb, unmap_dmabuf, vb->planes[i].mem_priv);
1967 vb->planes[i].dbuf_mapped = 0;
1971 static int vb2_internal_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking)
1973 struct vb2_buffer *vb = NULL;
1976 if (b->type != q->type) {
1977 dprintk(1, "dqbuf: invalid buffer type\n");
1980 ret = __vb2_get_done_vb(q, &vb, b, nonblocking);
1984 switch (vb->state) {
1985 case VB2_BUF_STATE_DONE:
1986 dprintk(3, "dqbuf: Returning done buffer\n");
1988 case VB2_BUF_STATE_ERROR:
1989 dprintk(3, "dqbuf: Returning done buffer with errors\n");
1992 dprintk(1, "dqbuf: Invalid buffer state\n");
1996 call_void_vb_qop(vb, buf_finish, vb);
1998 /* Fill buffer information for the userspace */
1999 __fill_v4l2_buffer(vb, b);
2000 /* Remove from videobuf queue */
2001 list_del(&vb->queued_entry);
2003 /* go back to dequeued state */
2006 dprintk(1, "dqbuf of buffer %d, with state %d\n",
2007 vb->v4l2_buf.index, vb->state);
2013 * vb2_dqbuf() - Dequeue a buffer to the userspace
2014 * @q: videobuf2 queue
2015 * @b: buffer structure passed from userspace to vidioc_dqbuf handler
2017 * @nonblocking: if true, this call will not sleep waiting for a buffer if no
2018 * buffers ready for dequeuing are present. Normally the driver
2019 * would be passing (file->f_flags & O_NONBLOCK) here
2021 * Should be called from vidioc_dqbuf ioctl handler of a driver.
2023 * 1) verifies the passed buffer,
2024 * 2) calls buf_finish callback in the driver (if provided), in which
2025 * driver can perform any additional operations that may be required before
2026 * returning the buffer to userspace, such as cache sync,
2027 * 3) the buffer struct members are filled with relevant information for
2030 * The return values from this function are intended to be directly returned
2031 * from vidioc_dqbuf handler in driver.
2033 int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking)
2036 dprintk(1, "dqbuf: file io in progress\n");
2039 return vb2_internal_dqbuf(q, b, nonblocking);
2041 EXPORT_SYMBOL_GPL(vb2_dqbuf);
2044 * __vb2_queue_cancel() - cancel and stop (pause) streaming
2046 * Removes all queued buffers from driver's queue and all buffers queued by
2047 * userspace from videobuf's queue. Returns to state after reqbufs.
2049 static void __vb2_queue_cancel(struct vb2_queue *q)
2054 * Tell driver to stop all transactions and release all queued
2057 if (q->start_streaming_called)
2058 call_qop(q, stop_streaming, q);
2060 q->start_streaming_called = 0;
2061 q->queued_count = 0;
2063 if (WARN_ON(atomic_read(&q->owned_by_drv_count))) {
2064 for (i = 0; i < q->num_buffers; ++i)
2065 if (q->bufs[i]->state == VB2_BUF_STATE_ACTIVE)
2066 vb2_buffer_done(q->bufs[i], VB2_BUF_STATE_ERROR);
2067 /* Must be zero now */
2068 WARN_ON(atomic_read(&q->owned_by_drv_count));
2072 * Remove all buffers from videobuf's list...
2074 INIT_LIST_HEAD(&q->queued_list);
2076 * ...and done list; userspace will not receive any buffers it
2077 * has not already dequeued before initiating cancel.
2079 INIT_LIST_HEAD(&q->done_list);
2080 atomic_set(&q->owned_by_drv_count, 0);
2081 wake_up_all(&q->done_wq);
2084 * Reinitialize all buffers for next use.
2085 * Make sure to call buf_finish for any queued buffers. Normally
2086 * that's done in dqbuf, but that's not going to happen when we
2087 * cancel the whole queue. Note: this code belongs here, not in
2088 * __vb2_dqbuf() since in vb2_internal_dqbuf() there is a critical
2089 * call to __fill_v4l2_buffer() after buf_finish(). That order can't
2090 * be changed, so we can't move the buf_finish() to __vb2_dqbuf().
2092 for (i = 0; i < q->num_buffers; ++i) {
2093 struct vb2_buffer *vb = q->bufs[i];
2095 if (vb->state != VB2_BUF_STATE_DEQUEUED) {
2096 vb->state = VB2_BUF_STATE_PREPARED;
2097 call_void_vb_qop(vb, buf_finish, vb);
2103 static int vb2_internal_streamon(struct vb2_queue *q, enum v4l2_buf_type type)
2107 if (type != q->type) {
2108 dprintk(1, "streamon: invalid stream type\n");
2113 dprintk(3, "streamon successful: already streaming\n");
2117 if (!q->num_buffers) {
2118 dprintk(1, "streamon: no buffers have been allocated\n");
2122 if (!q->num_buffers) {
2123 dprintk(1, "streamon: no buffers have been allocated\n");
2126 if (q->num_buffers < q->min_buffers_needed) {
2127 dprintk(1, "streamon: need at least %u allocated buffers\n",
2128 q->min_buffers_needed);
2133 * Tell driver to start streaming provided sufficient buffers
2136 if (q->queued_count >= q->min_buffers_needed) {
2137 ret = vb2_start_streaming(q);
2139 __vb2_queue_cancel(q);
2146 dprintk(3, "Streamon successful\n");
2151 * vb2_streamon - start streaming
2152 * @q: videobuf2 queue
2153 * @type: type argument passed from userspace to vidioc_streamon handler
2155 * Should be called from vidioc_streamon handler of a driver.
2157 * 1) verifies current state
2158 * 2) passes any previously queued buffers to the driver and starts streaming
2160 * The return values from this function are intended to be directly returned
2161 * from vidioc_streamon handler in the driver.
2163 int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type)
2166 dprintk(1, "streamon: file io in progress\n");
2169 return vb2_internal_streamon(q, type);
2171 EXPORT_SYMBOL_GPL(vb2_streamon);
2173 static int vb2_internal_streamoff(struct vb2_queue *q, enum v4l2_buf_type type)
2175 if (type != q->type) {
2176 dprintk(1, "streamoff: invalid stream type\n");
2181 * Cancel will pause streaming and remove all buffers from the driver
2182 * and videobuf, effectively returning control over them to userspace.
2184 * Note that we do this even if q->streaming == 0: if you prepare or
2185 * queue buffers, and then call streamoff without ever having called
2186 * streamon, you would still expect those buffers to be returned to
2187 * their normal dequeued state.
2189 __vb2_queue_cancel(q);
2191 dprintk(3, "Streamoff successful\n");
2196 * vb2_streamoff - stop streaming
2197 * @q: videobuf2 queue
2198 * @type: type argument passed from userspace to vidioc_streamoff handler
2200 * Should be called from vidioc_streamoff handler of a driver.
2202 * 1) verifies current state,
2203 * 2) stop streaming and dequeues any queued buffers, including those previously
2204 * passed to the driver (after waiting for the driver to finish).
2206 * This call can be used for pausing playback.
2207 * The return values from this function are intended to be directly returned
2208 * from vidioc_streamoff handler in the driver
2210 int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type)
2213 dprintk(1, "streamoff: file io in progress\n");
2216 return vb2_internal_streamoff(q, type);
2218 EXPORT_SYMBOL_GPL(vb2_streamoff);
2221 * __find_plane_by_offset() - find plane associated with the given offset off
2223 static int __find_plane_by_offset(struct vb2_queue *q, unsigned long off,
2224 unsigned int *_buffer, unsigned int *_plane)
2226 struct vb2_buffer *vb;
2227 unsigned int buffer, plane;
2230 * Go over all buffers and their planes, comparing the given offset
2231 * with an offset assigned to each plane. If a match is found,
2232 * return its buffer and plane numbers.
2234 for (buffer = 0; buffer < q->num_buffers; ++buffer) {
2235 vb = q->bufs[buffer];
2237 for (plane = 0; plane < vb->num_planes; ++plane) {
2238 if (vb->v4l2_planes[plane].m.mem_offset == off) {
2250 * vb2_expbuf() - Export a buffer as a file descriptor
2251 * @q: videobuf2 queue
2252 * @eb: export buffer structure passed from userspace to vidioc_expbuf
2255 * The return values from this function are intended to be directly returned
2256 * from vidioc_expbuf handler in driver.
2258 int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb)
2260 struct vb2_buffer *vb = NULL;
2261 struct vb2_plane *vb_plane;
2263 struct dma_buf *dbuf;
2265 if (q->memory != V4L2_MEMORY_MMAP) {
2266 dprintk(1, "Queue is not currently set up for mmap\n");
2270 if (!q->mem_ops->get_dmabuf) {
2271 dprintk(1, "Queue does not support DMA buffer exporting\n");
2275 if (eb->flags & ~(O_CLOEXEC | O_ACCMODE)) {
2276 dprintk(1, "Queue does support only O_CLOEXEC and access mode flags\n");
2280 if (eb->type != q->type) {
2281 dprintk(1, "qbuf: invalid buffer type\n");
2285 if (eb->index >= q->num_buffers) {
2286 dprintk(1, "buffer index out of range\n");
2290 vb = q->bufs[eb->index];
2292 if (eb->plane >= vb->num_planes) {
2293 dprintk(1, "buffer plane out of range\n");
2297 vb_plane = &vb->planes[eb->plane];
2299 dbuf = call_ptr_memop(vb, get_dmabuf, vb_plane->mem_priv, eb->flags & O_ACCMODE);
2300 if (IS_ERR_OR_NULL(dbuf)) {
2301 dprintk(1, "Failed to export buffer %d, plane %d\n",
2302 eb->index, eb->plane);
2306 ret = dma_buf_fd(dbuf, eb->flags & ~O_ACCMODE);
2308 dprintk(3, "buffer %d, plane %d failed to export (%d)\n",
2309 eb->index, eb->plane, ret);
2314 dprintk(3, "buffer %d, plane %d exported as %d descriptor\n",
2315 eb->index, eb->plane, ret);
2320 EXPORT_SYMBOL_GPL(vb2_expbuf);
2323 * vb2_mmap() - map video buffers into application address space
2324 * @q: videobuf2 queue
2325 * @vma: vma passed to the mmap file operation handler in the driver
2327 * Should be called from mmap file operation handler of a driver.
2328 * This function maps one plane of one of the available video buffers to
2329 * userspace. To map whole video memory allocated on reqbufs, this function
2330 * has to be called once per each plane per each buffer previously allocated.
2332 * When the userspace application calls mmap, it passes to it an offset returned
2333 * to it earlier by the means of vidioc_querybuf handler. That offset acts as
2334 * a "cookie", which is then used to identify the plane to be mapped.
2335 * This function finds a plane with a matching offset and a mapping is performed
2336 * by the means of a provided memory operation.
2338 * The return values from this function are intended to be directly returned
2339 * from the mmap handler in driver.
2341 int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma)
2343 unsigned long off = vma->vm_pgoff << PAGE_SHIFT;
2344 struct vb2_buffer *vb;
2345 unsigned int buffer, plane;
2347 unsigned long length;
2349 if (q->memory != V4L2_MEMORY_MMAP) {
2350 dprintk(1, "Queue is not currently set up for mmap\n");
2355 * Check memory area access mode.
2357 if (!(vma->vm_flags & VM_SHARED)) {
2358 dprintk(1, "Invalid vma flags, VM_SHARED needed\n");
2361 if (V4L2_TYPE_IS_OUTPUT(q->type)) {
2362 if (!(vma->vm_flags & VM_WRITE)) {
2363 dprintk(1, "Invalid vma flags, VM_WRITE needed\n");
2367 if (!(vma->vm_flags & VM_READ)) {
2368 dprintk(1, "Invalid vma flags, VM_READ needed\n");
2374 * Find the plane corresponding to the offset passed by userspace.
2376 ret = __find_plane_by_offset(q, off, &buffer, &plane);
2380 vb = q->bufs[buffer];
2383 * MMAP requires page_aligned buffers.
2384 * The buffer length was page_aligned at __vb2_buf_mem_alloc(),
2385 * so, we need to do the same here.
2387 length = PAGE_ALIGN(vb->v4l2_planes[plane].length);
2388 if (length < (vma->vm_end - vma->vm_start)) {
2390 "MMAP invalid, as it would overflow buffer length\n");
2394 ret = call_memop(vb, mmap, vb->planes[plane].mem_priv, vma);
2398 dprintk(3, "Buffer %d, plane %d successfully mapped\n", buffer, plane);
2401 EXPORT_SYMBOL_GPL(vb2_mmap);
2404 unsigned long vb2_get_unmapped_area(struct vb2_queue *q,
2407 unsigned long pgoff,
2408 unsigned long flags)
2410 unsigned long off = pgoff << PAGE_SHIFT;
2411 struct vb2_buffer *vb;
2412 unsigned int buffer, plane;
2415 if (q->memory != V4L2_MEMORY_MMAP) {
2416 dprintk(1, "Queue is not currently set up for mmap\n");
2421 * Find the plane corresponding to the offset passed by userspace.
2423 ret = __find_plane_by_offset(q, off, &buffer, &plane);
2427 vb = q->bufs[buffer];
2429 return (unsigned long)vb2_plane_vaddr(vb, plane);
2431 EXPORT_SYMBOL_GPL(vb2_get_unmapped_area);
2434 static int __vb2_init_fileio(struct vb2_queue *q, int read);
2435 static int __vb2_cleanup_fileio(struct vb2_queue *q);
2438 * vb2_poll() - implements poll userspace operation
2439 * @q: videobuf2 queue
2440 * @file: file argument passed to the poll file operation handler
2441 * @wait: wait argument passed to the poll file operation handler
2443 * This function implements poll file operation handler for a driver.
2444 * For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will
2445 * be informed that the file descriptor of a video device is available for
2447 * For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor
2448 * will be reported as available for writing.
2450 * If the driver uses struct v4l2_fh, then vb2_poll() will also check for any
2453 * The return values from this function are intended to be directly returned
2454 * from poll handler in driver.
2456 unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)
2458 struct video_device *vfd = video_devdata(file);
2459 unsigned long req_events = poll_requested_events(wait);
2460 struct vb2_buffer *vb = NULL;
2461 unsigned int res = 0;
2462 unsigned long flags;
2464 if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) {
2465 struct v4l2_fh *fh = file->private_data;
2467 if (v4l2_event_pending(fh))
2469 else if (req_events & POLLPRI)
2470 poll_wait(file, &fh->wait, wait);
2473 if (!V4L2_TYPE_IS_OUTPUT(q->type) && !(req_events & (POLLIN | POLLRDNORM)))
2475 if (V4L2_TYPE_IS_OUTPUT(q->type) && !(req_events & (POLLOUT | POLLWRNORM)))
2479 * Start file I/O emulator only if streaming API has not been used yet.
2481 if (q->num_buffers == 0 && q->fileio == NULL) {
2482 if (!V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_READ) &&
2483 (req_events & (POLLIN | POLLRDNORM))) {
2484 if (__vb2_init_fileio(q, 1))
2485 return res | POLLERR;
2487 if (V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_WRITE) &&
2488 (req_events & (POLLOUT | POLLWRNORM))) {
2489 if (__vb2_init_fileio(q, 0))
2490 return res | POLLERR;
2492 * Write to OUTPUT queue can be done immediately.
2494 return res | POLLOUT | POLLWRNORM;
2499 * There is nothing to wait for if no buffers have already been queued.
2501 if (list_empty(&q->queued_list))
2502 return res | POLLERR;
2504 if (list_empty(&q->done_list))
2505 poll_wait(file, &q->done_wq, wait);
2508 * Take first buffer available for dequeuing.
2510 spin_lock_irqsave(&q->done_lock, flags);
2511 if (!list_empty(&q->done_list))
2512 vb = list_first_entry(&q->done_list, struct vb2_buffer,
2514 spin_unlock_irqrestore(&q->done_lock, flags);
2516 if (vb && (vb->state == VB2_BUF_STATE_DONE
2517 || vb->state == VB2_BUF_STATE_ERROR)) {
2518 return (V4L2_TYPE_IS_OUTPUT(q->type)) ?
2519 res | POLLOUT | POLLWRNORM :
2520 res | POLLIN | POLLRDNORM;
2524 EXPORT_SYMBOL_GPL(vb2_poll);
2527 * vb2_queue_init() - initialize a videobuf2 queue
2528 * @q: videobuf2 queue; this structure should be allocated in driver
2530 * The vb2_queue structure should be allocated by the driver. The driver is
2531 * responsible of clearing it's content and setting initial values for some
2532 * required entries before calling this function.
2533 * q->ops, q->mem_ops, q->type and q->io_modes are mandatory. Please refer
2534 * to the struct vb2_queue description in include/media/videobuf2-core.h
2535 * for more information.
2537 int vb2_queue_init(struct vb2_queue *q)
2544 WARN_ON(!q->mem_ops) ||
2545 WARN_ON(!q->type) ||
2546 WARN_ON(!q->io_modes) ||
2547 WARN_ON(!q->ops->queue_setup) ||
2548 WARN_ON(!q->ops->buf_queue) ||
2549 WARN_ON(q->timestamp_flags &
2550 ~(V4L2_BUF_FLAG_TIMESTAMP_MASK |
2551 V4L2_BUF_FLAG_TSTAMP_SRC_MASK)))
2554 /* Warn that the driver should choose an appropriate timestamp type */
2555 WARN_ON((q->timestamp_flags & V4L2_BUF_FLAG_TIMESTAMP_MASK) ==
2556 V4L2_BUF_FLAG_TIMESTAMP_UNKNOWN);
2558 INIT_LIST_HEAD(&q->queued_list);
2559 INIT_LIST_HEAD(&q->done_list);
2560 spin_lock_init(&q->done_lock);
2561 init_waitqueue_head(&q->done_wq);
2563 if (q->buf_struct_size == 0)
2564 q->buf_struct_size = sizeof(struct vb2_buffer);
2568 EXPORT_SYMBOL_GPL(vb2_queue_init);
2571 * vb2_queue_release() - stop streaming, release the queue and free memory
2572 * @q: videobuf2 queue
2574 * This function stops streaming and performs necessary clean ups, including
2575 * freeing video buffer memory. The driver is responsible for freeing
2576 * the vb2_queue structure itself.
2578 void vb2_queue_release(struct vb2_queue *q)
2580 __vb2_cleanup_fileio(q);
2581 __vb2_queue_cancel(q);
2582 __vb2_queue_free(q, q->num_buffers);
2584 EXPORT_SYMBOL_GPL(vb2_queue_release);
2587 * struct vb2_fileio_buf - buffer context used by file io emulator
2589 * vb2 provides a compatibility layer and emulator of file io (read and
2590 * write) calls on top of streaming API. This structure is used for
2591 * tracking context related to the buffers.
2593 struct vb2_fileio_buf {
2597 unsigned int queued:1;
2601 * struct vb2_fileio_data - queue context used by file io emulator
2603 * @cur_index: the index of the buffer currently being read from or
2604 * written to. If equal to q->num_buffers then a new buffer
2606 * @initial_index: in the read() case all buffers are queued up immediately
2607 * in __vb2_init_fileio() and __vb2_perform_fileio() just cycles
2608 * buffers. However, in the write() case no buffers are initially
2609 * queued, instead whenever a buffer is full it is queued up by
2610 * __vb2_perform_fileio(). Only once all available buffers have
2611 * been queued up will __vb2_perform_fileio() start to dequeue
2612 * buffers. This means that initially __vb2_perform_fileio()
2613 * needs to know what buffer index to use when it is queuing up
2614 * the buffers for the first time. That initial index is stored
2615 * in this field. Once it is equal to q->num_buffers all
2616 * available buffers have been queued and __vb2_perform_fileio()
2617 * should start the normal dequeue/queue cycle.
2619 * vb2 provides a compatibility layer and emulator of file io (read and
2620 * write) calls on top of streaming API. For proper operation it required
2621 * this structure to save the driver state between each call of the read
2622 * or write function.
2624 struct vb2_fileio_data {
2625 struct v4l2_requestbuffers req;
2626 struct v4l2_buffer b;
2627 struct vb2_fileio_buf bufs[VIDEO_MAX_FRAME];
2628 unsigned int cur_index;
2629 unsigned int initial_index;
2630 unsigned int q_count;
2631 unsigned int dq_count;
2636 * __vb2_init_fileio() - initialize file io emulator
2637 * @q: videobuf2 queue
2638 * @read: mode selector (1 means read, 0 means write)
2640 static int __vb2_init_fileio(struct vb2_queue *q, int read)
2642 struct vb2_fileio_data *fileio;
2644 unsigned int count = 0;
2649 if (WARN_ON((read && !(q->io_modes & VB2_READ)) ||
2650 (!read && !(q->io_modes & VB2_WRITE))))
2654 * Check if device supports mapping buffers to kernel virtual space.
2656 if (!q->mem_ops->vaddr)
2660 * Check if streaming api has not been already activated.
2662 if (q->streaming || q->num_buffers > 0)
2666 * Start with count 1, driver can increase it in queue_setup()
2670 dprintk(3, "setting up file io: mode %s, count %d, flags %08x\n",
2671 (read) ? "read" : "write", count, q->io_flags);
2673 fileio = kzalloc(sizeof(struct vb2_fileio_data), GFP_KERNEL);
2677 fileio->flags = q->io_flags;
2680 * Request buffers and use MMAP type to force driver
2681 * to allocate buffers by itself.
2683 fileio->req.count = count;
2684 fileio->req.memory = V4L2_MEMORY_MMAP;
2685 fileio->req.type = q->type;
2686 ret = vb2_reqbufs(q, &fileio->req);
2691 * Check if plane_count is correct
2692 * (multiplane buffers are not supported).
2694 if (q->bufs[0]->num_planes != 1) {
2700 * Get kernel address of each buffer.
2702 for (i = 0; i < q->num_buffers; i++) {
2703 fileio->bufs[i].vaddr = vb2_plane_vaddr(q->bufs[i], 0);
2704 if (fileio->bufs[i].vaddr == NULL) {
2708 fileio->bufs[i].size = vb2_plane_size(q->bufs[i], 0);
2712 * Read mode requires pre queuing of all buffers.
2716 * Queue all buffers.
2718 for (i = 0; i < q->num_buffers; i++) {
2719 struct v4l2_buffer *b = &fileio->b;
2720 memset(b, 0, sizeof(*b));
2722 b->memory = q->memory;
2724 ret = vb2_qbuf(q, b);
2727 fileio->bufs[i].queued = 1;
2730 * All buffers have been queued, so mark that by setting
2731 * initial_index to q->num_buffers
2733 fileio->initial_index = q->num_buffers;
2734 fileio->cur_index = q->num_buffers;
2740 ret = vb2_streamon(q, q->type);
2749 fileio->req.count = 0;
2750 vb2_reqbufs(q, &fileio->req);
2758 * __vb2_cleanup_fileio() - free resourced used by file io emulator
2759 * @q: videobuf2 queue
2761 static int __vb2_cleanup_fileio(struct vb2_queue *q)
2763 struct vb2_fileio_data *fileio = q->fileio;
2766 vb2_internal_streamoff(q, q->type);
2768 fileio->req.count = 0;
2769 vb2_reqbufs(q, &fileio->req);
2771 dprintk(3, "file io emulator closed\n");
2777 * __vb2_perform_fileio() - perform a single file io (read or write) operation
2778 * @q: videobuf2 queue
2779 * @data: pointed to target userspace buffer
2780 * @count: number of bytes to read or write
2781 * @ppos: file handle position tracking pointer
2782 * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking)
2783 * @read: access mode selector (1 means read, 0 means write)
2785 static size_t __vb2_perform_fileio(struct vb2_queue *q, char __user *data, size_t count,
2786 loff_t *ppos, int nonblock, int read)
2788 struct vb2_fileio_data *fileio;
2789 struct vb2_fileio_buf *buf;
2792 dprintk(3, "file io: mode %s, offset %ld, count %zd, %sblocking\n",
2793 read ? "read" : "write", (long)*ppos, count,
2794 nonblock ? "non" : "");
2800 * Initialize emulator on first call.
2803 ret = __vb2_init_fileio(q, read);
2804 dprintk(3, "file io: vb2_init_fileio result: %d\n", ret);
2811 * Check if we need to dequeue the buffer.
2813 index = fileio->cur_index;
2814 if (index >= q->num_buffers) {
2816 * Call vb2_dqbuf to get buffer back.
2818 memset(&fileio->b, 0, sizeof(fileio->b));
2819 fileio->b.type = q->type;
2820 fileio->b.memory = q->memory;
2821 ret = vb2_internal_dqbuf(q, &fileio->b, nonblock);
2822 dprintk(5, "file io: vb2_dqbuf result: %d\n", ret);
2825 fileio->dq_count += 1;
2827 fileio->cur_index = index = fileio->b.index;
2828 buf = &fileio->bufs[index];
2831 * Get number of bytes filled by the driver
2835 buf->size = read ? vb2_get_plane_payload(q->bufs[index], 0)
2836 : vb2_plane_size(q->bufs[index], 0);
2838 buf = &fileio->bufs[index];
2842 * Limit count on last few bytes of the buffer.
2844 if (buf->pos + count > buf->size) {
2845 count = buf->size - buf->pos;
2846 dprintk(5, "reducing read count: %zd\n", count);
2850 * Transfer data to userspace.
2852 dprintk(3, "file io: copying %zd bytes - buffer %d, offset %u\n",
2853 count, index, buf->pos);
2855 ret = copy_to_user(data, buf->vaddr + buf->pos, count);
2857 ret = copy_from_user(buf->vaddr + buf->pos, data, count);
2859 dprintk(3, "file io: error copying data\n");
2870 * Queue next buffer if required.
2872 if (buf->pos == buf->size ||
2873 (!read && (fileio->flags & VB2_FILEIO_WRITE_IMMEDIATELY))) {
2875 * Check if this is the last buffer to read.
2877 if (read && (fileio->flags & VB2_FILEIO_READ_ONCE) &&
2878 fileio->dq_count == 1) {
2879 dprintk(3, "file io: read limit reached\n");
2880 return __vb2_cleanup_fileio(q);
2884 * Call vb2_qbuf and give buffer to the driver.
2886 memset(&fileio->b, 0, sizeof(fileio->b));
2887 fileio->b.type = q->type;
2888 fileio->b.memory = q->memory;
2889 fileio->b.index = index;
2890 fileio->b.bytesused = buf->pos;
2891 ret = vb2_internal_qbuf(q, &fileio->b);
2892 dprintk(5, "file io: vb2_dbuf result: %d\n", ret);
2897 * Buffer has been queued, update the status
2901 buf->size = vb2_plane_size(q->bufs[index], 0);
2902 fileio->q_count += 1;
2904 * If we are queuing up buffers for the first time, then
2905 * increase initial_index by one.
2907 if (fileio->initial_index < q->num_buffers)
2908 fileio->initial_index++;
2910 * The next buffer to use is either a buffer that's going to be
2911 * queued for the first time (initial_index < q->num_buffers)
2912 * or it is equal to q->num_buffers, meaning that the next
2913 * time we need to dequeue a buffer since we've now queued up
2914 * all the 'first time' buffers.
2916 fileio->cur_index = fileio->initial_index;
2920 * Return proper number of bytes processed.
2927 size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count,
2928 loff_t *ppos, int nonblocking)
2930 return __vb2_perform_fileio(q, data, count, ppos, nonblocking, 1);
2932 EXPORT_SYMBOL_GPL(vb2_read);
2934 size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count,
2935 loff_t *ppos, int nonblocking)
2937 return __vb2_perform_fileio(q, (char __user *) data, count,
2938 ppos, nonblocking, 0);
2940 EXPORT_SYMBOL_GPL(vb2_write);
2944 * The following functions are not part of the vb2 core API, but are helper
2945 * functions that plug into struct v4l2_ioctl_ops, struct v4l2_file_operations
2946 * and struct vb2_ops.
2947 * They contain boilerplate code that most if not all drivers have to do
2948 * and so they simplify the driver code.
2951 /* The queue is busy if there is a owner and you are not that owner. */
2952 static inline bool vb2_queue_is_busy(struct video_device *vdev, struct file *file)
2954 return vdev->queue->owner && vdev->queue->owner != file->private_data;
2957 /* vb2 ioctl helpers */
2959 int vb2_ioctl_reqbufs(struct file *file, void *priv,
2960 struct v4l2_requestbuffers *p)
2962 struct video_device *vdev = video_devdata(file);
2963 int res = __verify_memory_type(vdev->queue, p->memory, p->type);
2967 if (vb2_queue_is_busy(vdev, file))
2969 res = __reqbufs(vdev->queue, p);
2970 /* If count == 0, then the owner has released all buffers and he
2971 is no longer owner of the queue. Otherwise we have a new owner. */
2973 vdev->queue->owner = p->count ? file->private_data : NULL;
2976 EXPORT_SYMBOL_GPL(vb2_ioctl_reqbufs);
2978 int vb2_ioctl_create_bufs(struct file *file, void *priv,
2979 struct v4l2_create_buffers *p)
2981 struct video_device *vdev = video_devdata(file);
2982 int res = __verify_memory_type(vdev->queue, p->memory, p->format.type);
2984 p->index = vdev->queue->num_buffers;
2985 /* If count == 0, then just check if memory and type are valid.
2986 Any -EBUSY result from __verify_memory_type can be mapped to 0. */
2988 return res != -EBUSY ? res : 0;
2991 if (vb2_queue_is_busy(vdev, file))
2993 res = __create_bufs(vdev->queue, p);
2995 vdev->queue->owner = file->private_data;
2998 EXPORT_SYMBOL_GPL(vb2_ioctl_create_bufs);
3000 int vb2_ioctl_prepare_buf(struct file *file, void *priv,
3001 struct v4l2_buffer *p)
3003 struct video_device *vdev = video_devdata(file);
3005 if (vb2_queue_is_busy(vdev, file))
3007 return vb2_prepare_buf(vdev->queue, p);
3009 EXPORT_SYMBOL_GPL(vb2_ioctl_prepare_buf);
3011 int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p)
3013 struct video_device *vdev = video_devdata(file);
3015 /* No need to call vb2_queue_is_busy(), anyone can query buffers. */
3016 return vb2_querybuf(vdev->queue, p);
3018 EXPORT_SYMBOL_GPL(vb2_ioctl_querybuf);
3020 int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p)
3022 struct video_device *vdev = video_devdata(file);
3024 if (vb2_queue_is_busy(vdev, file))
3026 return vb2_qbuf(vdev->queue, p);
3028 EXPORT_SYMBOL_GPL(vb2_ioctl_qbuf);
3030 int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p)
3032 struct video_device *vdev = video_devdata(file);
3034 if (vb2_queue_is_busy(vdev, file))
3036 return vb2_dqbuf(vdev->queue, p, file->f_flags & O_NONBLOCK);
3038 EXPORT_SYMBOL_GPL(vb2_ioctl_dqbuf);
3040 int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i)
3042 struct video_device *vdev = video_devdata(file);
3044 if (vb2_queue_is_busy(vdev, file))
3046 return vb2_streamon(vdev->queue, i);
3048 EXPORT_SYMBOL_GPL(vb2_ioctl_streamon);
3050 int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i)
3052 struct video_device *vdev = video_devdata(file);
3054 if (vb2_queue_is_busy(vdev, file))
3056 return vb2_streamoff(vdev->queue, i);
3058 EXPORT_SYMBOL_GPL(vb2_ioctl_streamoff);
3060 int vb2_ioctl_expbuf(struct file *file, void *priv, struct v4l2_exportbuffer *p)
3062 struct video_device *vdev = video_devdata(file);
3064 if (vb2_queue_is_busy(vdev, file))
3066 return vb2_expbuf(vdev->queue, p);
3068 EXPORT_SYMBOL_GPL(vb2_ioctl_expbuf);
3070 /* v4l2_file_operations helpers */
3072 int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma)
3074 struct video_device *vdev = video_devdata(file);
3075 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
3078 if (lock && mutex_lock_interruptible(lock))
3079 return -ERESTARTSYS;
3080 err = vb2_mmap(vdev->queue, vma);
3085 EXPORT_SYMBOL_GPL(vb2_fop_mmap);
3087 int _vb2_fop_release(struct file *file, struct mutex *lock)
3089 struct video_device *vdev = video_devdata(file);
3091 if (file->private_data == vdev->queue->owner) {
3094 vb2_queue_release(vdev->queue);
3095 vdev->queue->owner = NULL;
3099 return v4l2_fh_release(file);
3101 EXPORT_SYMBOL_GPL(_vb2_fop_release);
3103 int vb2_fop_release(struct file *file)
3105 struct video_device *vdev = video_devdata(file);
3106 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
3108 return _vb2_fop_release(file, lock);
3110 EXPORT_SYMBOL_GPL(vb2_fop_release);
3112 ssize_t vb2_fop_write(struct file *file, const char __user *buf,
3113 size_t count, loff_t *ppos)
3115 struct video_device *vdev = video_devdata(file);
3116 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
3119 if (lock && mutex_lock_interruptible(lock))
3120 return -ERESTARTSYS;
3121 if (vb2_queue_is_busy(vdev, file))
3123 err = vb2_write(vdev->queue, buf, count, ppos,
3124 file->f_flags & O_NONBLOCK);
3125 if (vdev->queue->fileio)
3126 vdev->queue->owner = file->private_data;
3132 EXPORT_SYMBOL_GPL(vb2_fop_write);
3134 ssize_t vb2_fop_read(struct file *file, char __user *buf,
3135 size_t count, loff_t *ppos)
3137 struct video_device *vdev = video_devdata(file);
3138 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
3141 if (lock && mutex_lock_interruptible(lock))
3142 return -ERESTARTSYS;
3143 if (vb2_queue_is_busy(vdev, file))
3145 err = vb2_read(vdev->queue, buf, count, ppos,
3146 file->f_flags & O_NONBLOCK);
3147 if (vdev->queue->fileio)
3148 vdev->queue->owner = file->private_data;
3154 EXPORT_SYMBOL_GPL(vb2_fop_read);
3156 unsigned int vb2_fop_poll(struct file *file, poll_table *wait)
3158 struct video_device *vdev = video_devdata(file);
3159 struct vb2_queue *q = vdev->queue;
3160 struct mutex *lock = q->lock ? q->lock : vdev->lock;
3161 unsigned long req_events = poll_requested_events(wait);
3164 bool must_lock = false;
3166 /* Try to be smart: only lock if polling might start fileio,
3167 otherwise locking will only introduce unwanted delays. */
3168 if (q->num_buffers == 0 && q->fileio == NULL) {
3169 if (!V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_READ) &&
3170 (req_events & (POLLIN | POLLRDNORM)))
3172 else if (V4L2_TYPE_IS_OUTPUT(q->type) && (q->io_modes & VB2_WRITE) &&
3173 (req_events & (POLLOUT | POLLWRNORM)))
3177 /* If locking is needed, but this helper doesn't know how, then you
3178 shouldn't be using this helper but you should write your own. */
3179 WARN_ON(must_lock && !lock);
3181 if (must_lock && lock && mutex_lock_interruptible(lock))
3186 res = vb2_poll(vdev->queue, file, wait);
3188 /* If fileio was started, then we have a new queue owner. */
3189 if (must_lock && !fileio && q->fileio)
3190 q->owner = file->private_data;
3191 if (must_lock && lock)
3195 EXPORT_SYMBOL_GPL(vb2_fop_poll);
3198 unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr,
3199 unsigned long len, unsigned long pgoff, unsigned long flags)
3201 struct video_device *vdev = video_devdata(file);
3202 struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
3205 if (lock && mutex_lock_interruptible(lock))
3206 return -ERESTARTSYS;
3207 ret = vb2_get_unmapped_area(vdev->queue, addr, len, pgoff, flags);
3212 EXPORT_SYMBOL_GPL(vb2_fop_get_unmapped_area);
3215 /* vb2_ops helpers. Only use if vq->lock is non-NULL. */
3217 void vb2_ops_wait_prepare(struct vb2_queue *vq)
3219 mutex_unlock(vq->lock);
3221 EXPORT_SYMBOL_GPL(vb2_ops_wait_prepare);
3223 void vb2_ops_wait_finish(struct vb2_queue *vq)
3225 mutex_lock(vq->lock);
3227 EXPORT_SYMBOL_GPL(vb2_ops_wait_finish);
3229 MODULE_DESCRIPTION("Driver helper framework for Video for Linux 2");
3230 MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski");
3231 MODULE_LICENSE("GPL");