2 * videobuf2-core.c - video buffer 2 core 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/videobuf2-core.h>
28 #include <media/v4l2-mc.h>
30 #include <trace/events/vb2.h>
33 module_param(debug
, int, 0644);
35 #define dprintk(level, fmt, arg...) \
38 pr_info("vb2-core: %s: " fmt, __func__, ## arg); \
41 #ifdef CONFIG_VIDEO_ADV_DEBUG
44 * If advanced debugging is on, then count how often each op is called
45 * successfully, which can either be per-buffer or per-queue.
47 * This makes it easy to check that the 'init' and 'cleanup'
48 * (and variations thereof) stay balanced.
51 #define log_memop(vb, op) \
52 dprintk(2, "call_memop(%p, %d, %s)%s\n", \
53 (vb)->vb2_queue, (vb)->index, #op, \
54 (vb)->vb2_queue->mem_ops->op ? "" : " (nop)")
56 #define call_memop(vb, op, args...) \
58 struct vb2_queue *_q = (vb)->vb2_queue; \
62 err = _q->mem_ops->op ? _q->mem_ops->op(args) : 0; \
64 (vb)->cnt_mem_ ## op++; \
68 #define call_ptr_memop(vb, op, args...) \
70 struct vb2_queue *_q = (vb)->vb2_queue; \
74 ptr = _q->mem_ops->op ? _q->mem_ops->op(args) : NULL; \
75 if (!IS_ERR_OR_NULL(ptr)) \
76 (vb)->cnt_mem_ ## op++; \
80 #define call_void_memop(vb, op, args...) \
82 struct vb2_queue *_q = (vb)->vb2_queue; \
85 if (_q->mem_ops->op) \
86 _q->mem_ops->op(args); \
87 (vb)->cnt_mem_ ## op++; \
90 #define log_qop(q, op) \
91 dprintk(2, "call_qop(%p, %s)%s\n", q, #op, \
92 (q)->ops->op ? "" : " (nop)")
94 #define call_qop(q, op, args...) \
99 err = (q)->ops->op ? (q)->ops->op(args) : 0; \
105 #define call_void_qop(q, op, args...) \
109 (q)->ops->op(args); \
113 #define log_vb_qop(vb, op, args...) \
114 dprintk(2, "call_vb_qop(%p, %d, %s)%s\n", \
115 (vb)->vb2_queue, (vb)->index, #op, \
116 (vb)->vb2_queue->ops->op ? "" : " (nop)")
118 #define call_vb_qop(vb, op, args...) \
122 log_vb_qop(vb, op); \
123 err = (vb)->vb2_queue->ops->op ? \
124 (vb)->vb2_queue->ops->op(args) : 0; \
126 (vb)->cnt_ ## op++; \
130 #define call_void_vb_qop(vb, op, args...) \
132 log_vb_qop(vb, op); \
133 if ((vb)->vb2_queue->ops->op) \
134 (vb)->vb2_queue->ops->op(args); \
135 (vb)->cnt_ ## op++; \
140 #define call_memop(vb, op, args...) \
141 ((vb)->vb2_queue->mem_ops->op ? \
142 (vb)->vb2_queue->mem_ops->op(args) : 0)
144 #define call_ptr_memop(vb, op, args...) \
145 ((vb)->vb2_queue->mem_ops->op ? \
146 (vb)->vb2_queue->mem_ops->op(args) : NULL)
148 #define call_void_memop(vb, op, args...) \
150 if ((vb)->vb2_queue->mem_ops->op) \
151 (vb)->vb2_queue->mem_ops->op(args); \
154 #define call_qop(q, op, args...) \
155 ((q)->ops->op ? (q)->ops->op(args) : 0)
157 #define call_void_qop(q, op, args...) \
160 (q)->ops->op(args); \
163 #define call_vb_qop(vb, op, args...) \
164 ((vb)->vb2_queue->ops->op ? (vb)->vb2_queue->ops->op(args) : 0)
166 #define call_void_vb_qop(vb, op, args...) \
168 if ((vb)->vb2_queue->ops->op) \
169 (vb)->vb2_queue->ops->op(args); \
174 #define call_bufop(q, op, args...) \
177 if (q && q->buf_ops && q->buf_ops->op) \
178 ret = q->buf_ops->op(args); \
182 #define call_void_bufop(q, op, args...) \
184 if (q && q->buf_ops && q->buf_ops->op) \
185 q->buf_ops->op(args); \
188 static void __vb2_queue_cancel(struct vb2_queue
*q
);
189 static void __enqueue_in_driver(struct vb2_buffer
*vb
);
192 * __vb2_buf_mem_alloc() - allocate video memory for the given buffer
194 static int __vb2_buf_mem_alloc(struct vb2_buffer
*vb
)
196 struct vb2_queue
*q
= vb
->vb2_queue
;
197 enum dma_data_direction dma_dir
=
198 q
->is_output
? DMA_TO_DEVICE
: DMA_FROM_DEVICE
;
204 * Allocate memory for all planes in this buffer
205 * NOTE: mmapped areas should be page aligned
207 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
208 unsigned long size
= PAGE_ALIGN(vb
->planes
[plane
].length
);
210 mem_priv
= call_ptr_memop(vb
, alloc
,
211 q
->alloc_devs
[plane
] ? : q
->dev
,
212 q
->dma_attrs
, size
, dma_dir
, q
->gfp_flags
);
213 if (IS_ERR(mem_priv
)) {
215 ret
= PTR_ERR(mem_priv
);
219 /* Associate allocator private data with this plane */
220 vb
->planes
[plane
].mem_priv
= mem_priv
;
225 /* Free already allocated memory if one of the allocations failed */
226 for (; plane
> 0; --plane
) {
227 call_void_memop(vb
, put
, vb
->planes
[plane
- 1].mem_priv
);
228 vb
->planes
[plane
- 1].mem_priv
= NULL
;
235 * __vb2_buf_mem_free() - free memory of the given buffer
237 static void __vb2_buf_mem_free(struct vb2_buffer
*vb
)
241 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
242 call_void_memop(vb
, put
, vb
->planes
[plane
].mem_priv
);
243 vb
->planes
[plane
].mem_priv
= NULL
;
244 dprintk(3, "freed plane %d of buffer %d\n", plane
, vb
->index
);
249 * __vb2_buf_userptr_put() - release userspace memory associated with
252 static void __vb2_buf_userptr_put(struct vb2_buffer
*vb
)
256 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
257 if (vb
->planes
[plane
].mem_priv
)
258 call_void_memop(vb
, put_userptr
, vb
->planes
[plane
].mem_priv
);
259 vb
->planes
[plane
].mem_priv
= NULL
;
264 * __vb2_plane_dmabuf_put() - release memory associated with
265 * a DMABUF shared plane
267 static void __vb2_plane_dmabuf_put(struct vb2_buffer
*vb
, struct vb2_plane
*p
)
273 call_void_memop(vb
, unmap_dmabuf
, p
->mem_priv
);
275 call_void_memop(vb
, detach_dmabuf
, p
->mem_priv
);
276 dma_buf_put(p
->dbuf
);
283 * __vb2_buf_dmabuf_put() - release memory associated with
284 * a DMABUF shared buffer
286 static void __vb2_buf_dmabuf_put(struct vb2_buffer
*vb
)
290 for (plane
= 0; plane
< vb
->num_planes
; ++plane
)
291 __vb2_plane_dmabuf_put(vb
, &vb
->planes
[plane
]);
295 * __setup_offsets() - setup unique offsets ("cookies") for every plane in
298 static void __setup_offsets(struct vb2_buffer
*vb
)
300 struct vb2_queue
*q
= vb
->vb2_queue
;
302 unsigned long off
= 0;
305 struct vb2_buffer
*prev
= q
->bufs
[vb
->index
- 1];
306 struct vb2_plane
*p
= &prev
->planes
[prev
->num_planes
- 1];
308 off
= PAGE_ALIGN(p
->m
.offset
+ p
->length
);
311 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
312 vb
->planes
[plane
].m
.offset
= off
;
314 dprintk(3, "buffer %d, plane %d offset 0x%08lx\n",
315 vb
->index
, plane
, off
);
317 off
+= vb
->planes
[plane
].length
;
318 off
= PAGE_ALIGN(off
);
323 * __vb2_queue_alloc() - allocate videobuf buffer structures and (for MMAP type)
324 * video buffer memory for all buffers/planes on the queue and initializes the
327 * Returns the number of buffers successfully allocated.
329 static int __vb2_queue_alloc(struct vb2_queue
*q
, enum vb2_memory memory
,
330 unsigned int num_buffers
, unsigned int num_planes
,
331 const unsigned plane_sizes
[VB2_MAX_PLANES
])
333 unsigned int buffer
, plane
;
334 struct vb2_buffer
*vb
;
337 for (buffer
= 0; buffer
< num_buffers
; ++buffer
) {
338 /* Allocate videobuf buffer structures */
339 vb
= kzalloc(q
->buf_struct_size
, GFP_KERNEL
);
341 dprintk(1, "memory alloc for buffer struct failed\n");
345 vb
->state
= VB2_BUF_STATE_DEQUEUED
;
347 vb
->num_planes
= num_planes
;
348 vb
->index
= q
->num_buffers
+ buffer
;
351 for (plane
= 0; plane
< num_planes
; ++plane
) {
352 vb
->planes
[plane
].length
= plane_sizes
[plane
];
353 vb
->planes
[plane
].min_length
= plane_sizes
[plane
];
355 q
->bufs
[vb
->index
] = vb
;
357 /* Allocate video buffer memory for the MMAP type */
358 if (memory
== VB2_MEMORY_MMAP
) {
359 ret
= __vb2_buf_mem_alloc(vb
);
361 dprintk(1, "failed allocating memory for buffer %d\n",
363 q
->bufs
[vb
->index
] = NULL
;
369 * Call the driver-provided buffer initialization
370 * callback, if given. An error in initialization
371 * results in queue setup failure.
373 ret
= call_vb_qop(vb
, buf_init
, vb
);
375 dprintk(1, "buffer %d %p initialization failed\n",
377 __vb2_buf_mem_free(vb
);
378 q
->bufs
[vb
->index
] = NULL
;
385 dprintk(1, "allocated %d buffers, %d plane(s) each\n",
392 * __vb2_free_mem() - release all video buffer memory for a given queue
394 static void __vb2_free_mem(struct vb2_queue
*q
, unsigned int buffers
)
397 struct vb2_buffer
*vb
;
399 for (buffer
= q
->num_buffers
- buffers
; buffer
< q
->num_buffers
;
401 vb
= q
->bufs
[buffer
];
405 /* Free MMAP buffers or release USERPTR buffers */
406 if (q
->memory
== VB2_MEMORY_MMAP
)
407 __vb2_buf_mem_free(vb
);
408 else if (q
->memory
== VB2_MEMORY_DMABUF
)
409 __vb2_buf_dmabuf_put(vb
);
411 __vb2_buf_userptr_put(vb
);
416 * __vb2_queue_free() - free buffers at the end of the queue - video memory and
417 * related information, if no buffers are left return the queue to an
418 * uninitialized state. Might be called even if the queue has already been freed.
420 static int __vb2_queue_free(struct vb2_queue
*q
, unsigned int buffers
)
425 * Sanity check: when preparing a buffer the queue lock is released for
426 * a short while (see __buf_prepare for the details), which would allow
427 * a race with a reqbufs which can call this function. Removing the
428 * buffers from underneath __buf_prepare is obviously a bad idea, so we
429 * check if any of the buffers is in the state PREPARING, and if so we
430 * just return -EAGAIN.
432 for (buffer
= q
->num_buffers
- buffers
; buffer
< q
->num_buffers
;
434 if (q
->bufs
[buffer
] == NULL
)
436 if (q
->bufs
[buffer
]->state
== VB2_BUF_STATE_PREPARING
) {
437 dprintk(1, "preparing buffers, cannot free\n");
442 /* Call driver-provided cleanup function for each buffer, if provided */
443 for (buffer
= q
->num_buffers
- buffers
; buffer
< q
->num_buffers
;
445 struct vb2_buffer
*vb
= q
->bufs
[buffer
];
447 if (vb
&& vb
->planes
[0].mem_priv
)
448 call_void_vb_qop(vb
, buf_cleanup
, vb
);
451 /* Release video buffer memory */
452 __vb2_free_mem(q
, buffers
);
454 #ifdef CONFIG_VIDEO_ADV_DEBUG
456 * Check that all the calls were balances during the life-time of this
457 * queue. If not (or if the debug level is 1 or up), then dump the
458 * counters to the kernel log.
460 if (q
->num_buffers
) {
461 bool unbalanced
= q
->cnt_start_streaming
!= q
->cnt_stop_streaming
||
462 q
->cnt_wait_prepare
!= q
->cnt_wait_finish
;
464 if (unbalanced
|| debug
) {
465 pr_info("vb2: counters for queue %p:%s\n", q
,
466 unbalanced
? " UNBALANCED!" : "");
467 pr_info("vb2: setup: %u start_streaming: %u stop_streaming: %u\n",
468 q
->cnt_queue_setup
, q
->cnt_start_streaming
,
469 q
->cnt_stop_streaming
);
470 pr_info("vb2: wait_prepare: %u wait_finish: %u\n",
471 q
->cnt_wait_prepare
, q
->cnt_wait_finish
);
473 q
->cnt_queue_setup
= 0;
474 q
->cnt_wait_prepare
= 0;
475 q
->cnt_wait_finish
= 0;
476 q
->cnt_start_streaming
= 0;
477 q
->cnt_stop_streaming
= 0;
479 for (buffer
= 0; buffer
< q
->num_buffers
; ++buffer
) {
480 struct vb2_buffer
*vb
= q
->bufs
[buffer
];
481 bool unbalanced
= vb
->cnt_mem_alloc
!= vb
->cnt_mem_put
||
482 vb
->cnt_mem_prepare
!= vb
->cnt_mem_finish
||
483 vb
->cnt_mem_get_userptr
!= vb
->cnt_mem_put_userptr
||
484 vb
->cnt_mem_attach_dmabuf
!= vb
->cnt_mem_detach_dmabuf
||
485 vb
->cnt_mem_map_dmabuf
!= vb
->cnt_mem_unmap_dmabuf
||
486 vb
->cnt_buf_queue
!= vb
->cnt_buf_done
||
487 vb
->cnt_buf_prepare
!= vb
->cnt_buf_finish
||
488 vb
->cnt_buf_init
!= vb
->cnt_buf_cleanup
;
490 if (unbalanced
|| debug
) {
491 pr_info("vb2: counters for queue %p, buffer %d:%s\n",
492 q
, buffer
, unbalanced
? " UNBALANCED!" : "");
493 pr_info("vb2: buf_init: %u buf_cleanup: %u buf_prepare: %u buf_finish: %u\n",
494 vb
->cnt_buf_init
, vb
->cnt_buf_cleanup
,
495 vb
->cnt_buf_prepare
, vb
->cnt_buf_finish
);
496 pr_info("vb2: buf_queue: %u buf_done: %u\n",
497 vb
->cnt_buf_queue
, vb
->cnt_buf_done
);
498 pr_info("vb2: alloc: %u put: %u prepare: %u finish: %u mmap: %u\n",
499 vb
->cnt_mem_alloc
, vb
->cnt_mem_put
,
500 vb
->cnt_mem_prepare
, vb
->cnt_mem_finish
,
502 pr_info("vb2: get_userptr: %u put_userptr: %u\n",
503 vb
->cnt_mem_get_userptr
, vb
->cnt_mem_put_userptr
);
504 pr_info("vb2: attach_dmabuf: %u detach_dmabuf: %u map_dmabuf: %u unmap_dmabuf: %u\n",
505 vb
->cnt_mem_attach_dmabuf
, vb
->cnt_mem_detach_dmabuf
,
506 vb
->cnt_mem_map_dmabuf
, vb
->cnt_mem_unmap_dmabuf
);
507 pr_info("vb2: get_dmabuf: %u num_users: %u vaddr: %u cookie: %u\n",
508 vb
->cnt_mem_get_dmabuf
,
509 vb
->cnt_mem_num_users
,
516 /* Free videobuf buffers */
517 for (buffer
= q
->num_buffers
- buffers
; buffer
< q
->num_buffers
;
519 kfree(q
->bufs
[buffer
]);
520 q
->bufs
[buffer
] = NULL
;
523 q
->num_buffers
-= buffers
;
524 if (!q
->num_buffers
) {
526 INIT_LIST_HEAD(&q
->queued_list
);
531 bool vb2_buffer_in_use(struct vb2_queue
*q
, struct vb2_buffer
*vb
)
534 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
535 void *mem_priv
= vb
->planes
[plane
].mem_priv
;
537 * If num_users() has not been provided, call_memop
538 * will return 0, apparently nobody cares about this
539 * case anyway. If num_users() returns more than 1,
540 * we are not the only user of the plane's memory.
542 if (mem_priv
&& call_memop(vb
, num_users
, mem_priv
) > 1)
547 EXPORT_SYMBOL(vb2_buffer_in_use
);
550 * __buffers_in_use() - return true if any buffers on the queue are in use and
551 * the queue cannot be freed (by the means of REQBUFS(0)) call
553 static bool __buffers_in_use(struct vb2_queue
*q
)
556 for (buffer
= 0; buffer
< q
->num_buffers
; ++buffer
) {
557 if (vb2_buffer_in_use(q
, q
->bufs
[buffer
]))
563 void vb2_core_querybuf(struct vb2_queue
*q
, unsigned int index
, void *pb
)
565 call_void_bufop(q
, fill_user_buffer
, q
->bufs
[index
], pb
);
567 EXPORT_SYMBOL_GPL(vb2_core_querybuf
);
570 * __verify_userptr_ops() - verify that all memory operations required for
571 * USERPTR queue type have been provided
573 static int __verify_userptr_ops(struct vb2_queue
*q
)
575 if (!(q
->io_modes
& VB2_USERPTR
) || !q
->mem_ops
->get_userptr
||
576 !q
->mem_ops
->put_userptr
)
583 * __verify_mmap_ops() - verify that all memory operations required for
584 * MMAP queue type have been provided
586 static int __verify_mmap_ops(struct vb2_queue
*q
)
588 if (!(q
->io_modes
& VB2_MMAP
) || !q
->mem_ops
->alloc
||
589 !q
->mem_ops
->put
|| !q
->mem_ops
->mmap
)
596 * __verify_dmabuf_ops() - verify that all memory operations required for
597 * DMABUF queue type have been provided
599 static int __verify_dmabuf_ops(struct vb2_queue
*q
)
601 if (!(q
->io_modes
& VB2_DMABUF
) || !q
->mem_ops
->attach_dmabuf
||
602 !q
->mem_ops
->detach_dmabuf
|| !q
->mem_ops
->map_dmabuf
||
603 !q
->mem_ops
->unmap_dmabuf
)
609 int vb2_verify_memory_type(struct vb2_queue
*q
,
610 enum vb2_memory memory
, unsigned int type
)
612 if (memory
!= VB2_MEMORY_MMAP
&& memory
!= VB2_MEMORY_USERPTR
&&
613 memory
!= VB2_MEMORY_DMABUF
) {
614 dprintk(1, "unsupported memory type\n");
618 if (type
!= q
->type
) {
619 dprintk(1, "requested type is incorrect\n");
624 * Make sure all the required memory ops for given memory type
627 if (memory
== VB2_MEMORY_MMAP
&& __verify_mmap_ops(q
)) {
628 dprintk(1, "MMAP for current setup unsupported\n");
632 if (memory
== VB2_MEMORY_USERPTR
&& __verify_userptr_ops(q
)) {
633 dprintk(1, "USERPTR for current setup unsupported\n");
637 if (memory
== VB2_MEMORY_DMABUF
&& __verify_dmabuf_ops(q
)) {
638 dprintk(1, "DMABUF for current setup unsupported\n");
643 * Place the busy tests at the end: -EBUSY can be ignored when
644 * create_bufs is called with count == 0, but count == 0 should still
645 * do the memory and type validation.
647 if (vb2_fileio_is_active(q
)) {
648 dprintk(1, "file io in progress\n");
653 EXPORT_SYMBOL(vb2_verify_memory_type
);
655 int vb2_core_reqbufs(struct vb2_queue
*q
, enum vb2_memory memory
,
658 unsigned int num_buffers
, allocated_buffers
, num_planes
= 0;
659 unsigned plane_sizes
[VB2_MAX_PLANES
] = { };
663 dprintk(1, "streaming active\n");
667 if (*count
== 0 || q
->num_buffers
!= 0 || q
->memory
!= memory
) {
669 * We already have buffers allocated, so first check if they
670 * are not in use and can be freed.
672 mutex_lock(&q
->mmap_lock
);
673 if (q
->memory
== VB2_MEMORY_MMAP
&& __buffers_in_use(q
)) {
674 mutex_unlock(&q
->mmap_lock
);
675 dprintk(1, "memory in use, cannot free\n");
680 * Call queue_cancel to clean up any buffers in the PREPARED or
681 * QUEUED state which is possible if buffers were prepared or
682 * queued without ever calling STREAMON.
684 __vb2_queue_cancel(q
);
685 ret
= __vb2_queue_free(q
, q
->num_buffers
);
686 mutex_unlock(&q
->mmap_lock
);
691 * In case of REQBUFS(0) return immediately without calling
692 * driver's queue_setup() callback and allocating resources.
699 * Make sure the requested values and current defaults are sane.
701 num_buffers
= min_t(unsigned int, *count
, VB2_MAX_FRAME
);
702 num_buffers
= max_t(unsigned int, num_buffers
, q
->min_buffers_needed
);
703 memset(q
->alloc_devs
, 0, sizeof(q
->alloc_devs
));
707 * Ask the driver how many buffers and planes per buffer it requires.
708 * Driver also sets the size and allocator context for each plane.
710 ret
= call_qop(q
, queue_setup
, q
, &num_buffers
, &num_planes
,
711 plane_sizes
, q
->alloc_devs
);
715 /* Finally, allocate buffers and video memory */
717 __vb2_queue_alloc(q
, memory
, num_buffers
, num_planes
, plane_sizes
);
718 if (allocated_buffers
== 0) {
719 dprintk(1, "memory allocation failed\n");
724 * There is no point in continuing if we can't allocate the minimum
725 * number of buffers needed by this vb2_queue.
727 if (allocated_buffers
< q
->min_buffers_needed
)
731 * Check if driver can handle the allocated number of buffers.
733 if (!ret
&& allocated_buffers
< num_buffers
) {
734 num_buffers
= allocated_buffers
;
736 * num_planes is set by the previous queue_setup(), but since it
737 * signals to queue_setup() whether it is called from create_bufs()
738 * vs reqbufs() we zero it here to signal that queue_setup() is
739 * called for the reqbufs() case.
743 ret
= call_qop(q
, queue_setup
, q
, &num_buffers
,
744 &num_planes
, plane_sizes
, q
->alloc_devs
);
746 if (!ret
&& allocated_buffers
< num_buffers
)
750 * Either the driver has accepted a smaller number of buffers,
751 * or .queue_setup() returned an error
755 mutex_lock(&q
->mmap_lock
);
756 q
->num_buffers
= allocated_buffers
;
760 * Note: __vb2_queue_free() will subtract 'allocated_buffers'
761 * from q->num_buffers.
763 __vb2_queue_free(q
, allocated_buffers
);
764 mutex_unlock(&q
->mmap_lock
);
767 mutex_unlock(&q
->mmap_lock
);
770 * Return the number of successfully allocated buffers
773 *count
= allocated_buffers
;
774 q
->waiting_for_buffers
= !q
->is_output
;
778 EXPORT_SYMBOL_GPL(vb2_core_reqbufs
);
780 int vb2_core_create_bufs(struct vb2_queue
*q
, enum vb2_memory memory
,
781 unsigned int *count
, unsigned requested_planes
,
782 const unsigned requested_sizes
[])
784 unsigned int num_planes
= 0, num_buffers
, allocated_buffers
;
785 unsigned plane_sizes
[VB2_MAX_PLANES
] = { };
788 if (q
->num_buffers
== VB2_MAX_FRAME
) {
789 dprintk(1, "maximum number of buffers already allocated\n");
793 if (!q
->num_buffers
) {
794 memset(q
->alloc_devs
, 0, sizeof(q
->alloc_devs
));
796 q
->waiting_for_buffers
= !q
->is_output
;
799 num_buffers
= min(*count
, VB2_MAX_FRAME
- q
->num_buffers
);
801 if (requested_planes
&& requested_sizes
) {
802 num_planes
= requested_planes
;
803 memcpy(plane_sizes
, requested_sizes
, sizeof(plane_sizes
));
807 * Ask the driver, whether the requested number of buffers, planes per
808 * buffer and their sizes are acceptable
810 ret
= call_qop(q
, queue_setup
, q
, &num_buffers
,
811 &num_planes
, plane_sizes
, q
->alloc_devs
);
815 /* Finally, allocate buffers and video memory */
816 allocated_buffers
= __vb2_queue_alloc(q
, memory
, num_buffers
,
817 num_planes
, plane_sizes
);
818 if (allocated_buffers
== 0) {
819 dprintk(1, "memory allocation failed\n");
824 * Check if driver can handle the so far allocated number of buffers.
826 if (allocated_buffers
< num_buffers
) {
827 num_buffers
= allocated_buffers
;
830 * q->num_buffers contains the total number of buffers, that the
831 * queue driver has set up
833 ret
= call_qop(q
, queue_setup
, q
, &num_buffers
,
834 &num_planes
, plane_sizes
, q
->alloc_devs
);
836 if (!ret
&& allocated_buffers
< num_buffers
)
840 * Either the driver has accepted a smaller number of buffers,
841 * or .queue_setup() returned an error
845 mutex_lock(&q
->mmap_lock
);
846 q
->num_buffers
+= allocated_buffers
;
850 * Note: __vb2_queue_free() will subtract 'allocated_buffers'
851 * from q->num_buffers.
853 __vb2_queue_free(q
, allocated_buffers
);
854 mutex_unlock(&q
->mmap_lock
);
857 mutex_unlock(&q
->mmap_lock
);
860 * Return the number of successfully allocated buffers
863 *count
= allocated_buffers
;
867 EXPORT_SYMBOL_GPL(vb2_core_create_bufs
);
869 void *vb2_plane_vaddr(struct vb2_buffer
*vb
, unsigned int plane_no
)
871 if (plane_no
>= vb
->num_planes
|| !vb
->planes
[plane_no
].mem_priv
)
874 return call_ptr_memop(vb
, vaddr
, vb
->planes
[plane_no
].mem_priv
);
877 EXPORT_SYMBOL_GPL(vb2_plane_vaddr
);
879 void *vb2_plane_cookie(struct vb2_buffer
*vb
, unsigned int plane_no
)
881 if (plane_no
>= vb
->num_planes
|| !vb
->planes
[plane_no
].mem_priv
)
884 return call_ptr_memop(vb
, cookie
, vb
->planes
[plane_no
].mem_priv
);
886 EXPORT_SYMBOL_GPL(vb2_plane_cookie
);
888 void vb2_buffer_done(struct vb2_buffer
*vb
, enum vb2_buffer_state state
)
890 struct vb2_queue
*q
= vb
->vb2_queue
;
894 if (WARN_ON(vb
->state
!= VB2_BUF_STATE_ACTIVE
))
897 if (WARN_ON(state
!= VB2_BUF_STATE_DONE
&&
898 state
!= VB2_BUF_STATE_ERROR
&&
899 state
!= VB2_BUF_STATE_QUEUED
&&
900 state
!= VB2_BUF_STATE_REQUEUEING
))
901 state
= VB2_BUF_STATE_ERROR
;
903 #ifdef CONFIG_VIDEO_ADV_DEBUG
905 * Although this is not a callback, it still does have to balance
906 * with the buf_queue op. So update this counter manually.
910 dprintk(4, "done processing on buffer %d, state: %d\n",
914 for (plane
= 0; plane
< vb
->num_planes
; ++plane
)
915 call_void_memop(vb
, finish
, vb
->planes
[plane
].mem_priv
);
917 spin_lock_irqsave(&q
->done_lock
, flags
);
918 if (state
== VB2_BUF_STATE_QUEUED
||
919 state
== VB2_BUF_STATE_REQUEUEING
) {
920 vb
->state
= VB2_BUF_STATE_QUEUED
;
922 /* Add the buffer to the done buffers list */
923 list_add_tail(&vb
->done_entry
, &q
->done_list
);
926 atomic_dec(&q
->owned_by_drv_count
);
927 spin_unlock_irqrestore(&q
->done_lock
, flags
);
929 trace_vb2_buf_done(q
, vb
);
932 case VB2_BUF_STATE_QUEUED
:
934 case VB2_BUF_STATE_REQUEUEING
:
935 if (q
->start_streaming_called
)
936 __enqueue_in_driver(vb
);
939 /* Inform any processes that may be waiting for buffers */
940 wake_up(&q
->done_wq
);
944 EXPORT_SYMBOL_GPL(vb2_buffer_done
);
946 void vb2_discard_done(struct vb2_queue
*q
)
948 struct vb2_buffer
*vb
;
951 spin_lock_irqsave(&q
->done_lock
, flags
);
952 list_for_each_entry(vb
, &q
->done_list
, done_entry
)
953 vb
->state
= VB2_BUF_STATE_ERROR
;
954 spin_unlock_irqrestore(&q
->done_lock
, flags
);
956 EXPORT_SYMBOL_GPL(vb2_discard_done
);
959 * __qbuf_mmap() - handle qbuf of an MMAP buffer
961 static int __qbuf_mmap(struct vb2_buffer
*vb
, const void *pb
)
966 ret
= call_bufop(vb
->vb2_queue
, fill_vb2_buffer
,
968 return ret
? ret
: call_vb_qop(vb
, buf_prepare
, vb
);
972 * __qbuf_userptr() - handle qbuf of a USERPTR buffer
974 static int __qbuf_userptr(struct vb2_buffer
*vb
, const void *pb
)
976 struct vb2_plane planes
[VB2_MAX_PLANES
];
977 struct vb2_queue
*q
= vb
->vb2_queue
;
981 enum dma_data_direction dma_dir
=
982 q
->is_output
? DMA_TO_DEVICE
: DMA_FROM_DEVICE
;
983 bool reacquired
= vb
->planes
[0].mem_priv
== NULL
;
985 memset(planes
, 0, sizeof(planes
[0]) * vb
->num_planes
);
986 /* Copy relevant information provided by the userspace */
988 ret
= call_bufop(vb
->vb2_queue
, fill_vb2_buffer
,
993 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
994 /* Skip the plane if already verified */
995 if (vb
->planes
[plane
].m
.userptr
&&
996 vb
->planes
[plane
].m
.userptr
== planes
[plane
].m
.userptr
997 && vb
->planes
[plane
].length
== planes
[plane
].length
)
1000 dprintk(3, "userspace address for plane %d changed, reacquiring memory\n",
1003 /* Check if the provided plane buffer is large enough */
1004 if (planes
[plane
].length
< vb
->planes
[plane
].min_length
) {
1005 dprintk(1, "provided buffer size %u is less than setup size %u for plane %d\n",
1006 planes
[plane
].length
,
1007 vb
->planes
[plane
].min_length
,
1013 /* Release previously acquired memory if present */
1014 if (vb
->planes
[plane
].mem_priv
) {
1017 call_void_vb_qop(vb
, buf_cleanup
, vb
);
1019 call_void_memop(vb
, put_userptr
, vb
->planes
[plane
].mem_priv
);
1022 vb
->planes
[plane
].mem_priv
= NULL
;
1023 vb
->planes
[plane
].bytesused
= 0;
1024 vb
->planes
[plane
].length
= 0;
1025 vb
->planes
[plane
].m
.userptr
= 0;
1026 vb
->planes
[plane
].data_offset
= 0;
1028 /* Acquire each plane's memory */
1029 mem_priv
= call_ptr_memop(vb
, get_userptr
,
1030 q
->alloc_devs
[plane
] ? : q
->dev
,
1031 planes
[plane
].m
.userptr
,
1032 planes
[plane
].length
, dma_dir
);
1033 if (IS_ERR(mem_priv
)) {
1034 dprintk(1, "failed acquiring userspace memory for plane %d\n",
1036 ret
= PTR_ERR(mem_priv
);
1039 vb
->planes
[plane
].mem_priv
= mem_priv
;
1043 * Now that everything is in order, copy relevant information
1044 * provided by userspace.
1046 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1047 vb
->planes
[plane
].bytesused
= planes
[plane
].bytesused
;
1048 vb
->planes
[plane
].length
= planes
[plane
].length
;
1049 vb
->planes
[plane
].m
.userptr
= planes
[plane
].m
.userptr
;
1050 vb
->planes
[plane
].data_offset
= planes
[plane
].data_offset
;
1055 * One or more planes changed, so we must call buf_init to do
1056 * the driver-specific initialization on the newly acquired
1057 * buffer, if provided.
1059 ret
= call_vb_qop(vb
, buf_init
, vb
);
1061 dprintk(1, "buffer initialization failed\n");
1066 ret
= call_vb_qop(vb
, buf_prepare
, vb
);
1068 dprintk(1, "buffer preparation failed\n");
1069 call_void_vb_qop(vb
, buf_cleanup
, vb
);
1075 /* In case of errors, release planes that were already acquired */
1076 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1077 if (vb
->planes
[plane
].mem_priv
)
1078 call_void_memop(vb
, put_userptr
,
1079 vb
->planes
[plane
].mem_priv
);
1080 vb
->planes
[plane
].mem_priv
= NULL
;
1081 vb
->planes
[plane
].m
.userptr
= 0;
1082 vb
->planes
[plane
].length
= 0;
1089 * __qbuf_dmabuf() - handle qbuf of a DMABUF buffer
1091 static int __qbuf_dmabuf(struct vb2_buffer
*vb
, const void *pb
)
1093 struct vb2_plane planes
[VB2_MAX_PLANES
];
1094 struct vb2_queue
*q
= vb
->vb2_queue
;
1098 enum dma_data_direction dma_dir
=
1099 q
->is_output
? DMA_TO_DEVICE
: DMA_FROM_DEVICE
;
1100 bool reacquired
= vb
->planes
[0].mem_priv
== NULL
;
1102 memset(planes
, 0, sizeof(planes
[0]) * vb
->num_planes
);
1103 /* Copy relevant information provided by the userspace */
1105 ret
= call_bufop(vb
->vb2_queue
, fill_vb2_buffer
,
1110 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1111 struct dma_buf
*dbuf
= dma_buf_get(planes
[plane
].m
.fd
);
1113 if (IS_ERR_OR_NULL(dbuf
)) {
1114 dprintk(1, "invalid dmabuf fd for plane %d\n",
1120 /* use DMABUF size if length is not provided */
1121 if (planes
[plane
].length
== 0)
1122 planes
[plane
].length
= dbuf
->size
;
1124 if (planes
[plane
].length
< vb
->planes
[plane
].min_length
) {
1125 dprintk(1, "invalid dmabuf length %u for plane %d, minimum length %u\n",
1126 planes
[plane
].length
, plane
,
1127 vb
->planes
[plane
].min_length
);
1133 /* Skip the plane if already verified */
1134 if (dbuf
== vb
->planes
[plane
].dbuf
&&
1135 vb
->planes
[plane
].length
== planes
[plane
].length
) {
1140 dprintk(1, "buffer for plane %d changed\n", plane
);
1144 call_void_vb_qop(vb
, buf_cleanup
, vb
);
1147 /* Release previously acquired memory if present */
1148 __vb2_plane_dmabuf_put(vb
, &vb
->planes
[plane
]);
1149 vb
->planes
[plane
].bytesused
= 0;
1150 vb
->planes
[plane
].length
= 0;
1151 vb
->planes
[plane
].m
.fd
= 0;
1152 vb
->planes
[plane
].data_offset
= 0;
1154 /* Acquire each plane's memory */
1155 mem_priv
= call_ptr_memop(vb
, attach_dmabuf
,
1156 q
->alloc_devs
[plane
] ? : q
->dev
,
1157 dbuf
, planes
[plane
].length
, dma_dir
);
1158 if (IS_ERR(mem_priv
)) {
1159 dprintk(1, "failed to attach dmabuf\n");
1160 ret
= PTR_ERR(mem_priv
);
1165 vb
->planes
[plane
].dbuf
= dbuf
;
1166 vb
->planes
[plane
].mem_priv
= mem_priv
;
1170 * This pins the buffer(s) with dma_buf_map_attachment()). It's done
1171 * here instead just before the DMA, while queueing the buffer(s) so
1172 * userspace knows sooner rather than later if the dma-buf map fails.
1174 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1175 ret
= call_memop(vb
, map_dmabuf
, vb
->planes
[plane
].mem_priv
);
1177 dprintk(1, "failed to map dmabuf for plane %d\n",
1181 vb
->planes
[plane
].dbuf_mapped
= 1;
1185 * Now that everything is in order, copy relevant information
1186 * provided by userspace.
1188 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1189 vb
->planes
[plane
].bytesused
= planes
[plane
].bytesused
;
1190 vb
->planes
[plane
].length
= planes
[plane
].length
;
1191 vb
->planes
[plane
].m
.fd
= planes
[plane
].m
.fd
;
1192 vb
->planes
[plane
].data_offset
= planes
[plane
].data_offset
;
1197 * Call driver-specific initialization on the newly acquired buffer,
1200 ret
= call_vb_qop(vb
, buf_init
, vb
);
1202 dprintk(1, "buffer initialization failed\n");
1207 ret
= call_vb_qop(vb
, buf_prepare
, vb
);
1209 dprintk(1, "buffer preparation failed\n");
1210 call_void_vb_qop(vb
, buf_cleanup
, vb
);
1216 /* In case of errors, release planes that were already acquired */
1217 __vb2_buf_dmabuf_put(vb
);
1223 * __enqueue_in_driver() - enqueue a vb2_buffer in driver for processing
1225 static void __enqueue_in_driver(struct vb2_buffer
*vb
)
1227 struct vb2_queue
*q
= vb
->vb2_queue
;
1230 vb
->state
= VB2_BUF_STATE_ACTIVE
;
1231 atomic_inc(&q
->owned_by_drv_count
);
1233 trace_vb2_buf_queue(q
, vb
);
1236 for (plane
= 0; plane
< vb
->num_planes
; ++plane
)
1237 call_void_memop(vb
, prepare
, vb
->planes
[plane
].mem_priv
);
1239 call_void_vb_qop(vb
, buf_queue
, vb
);
1242 static int __buf_prepare(struct vb2_buffer
*vb
, const void *pb
)
1244 struct vb2_queue
*q
= vb
->vb2_queue
;
1248 dprintk(1, "fatal error occurred on queue\n");
1252 vb
->state
= VB2_BUF_STATE_PREPARING
;
1254 switch (q
->memory
) {
1255 case VB2_MEMORY_MMAP
:
1256 ret
= __qbuf_mmap(vb
, pb
);
1258 case VB2_MEMORY_USERPTR
:
1259 ret
= __qbuf_userptr(vb
, pb
);
1261 case VB2_MEMORY_DMABUF
:
1262 ret
= __qbuf_dmabuf(vb
, pb
);
1265 WARN(1, "Invalid queue type\n");
1270 dprintk(1, "buffer preparation failed: %d\n", ret
);
1271 vb
->state
= ret
? VB2_BUF_STATE_DEQUEUED
: VB2_BUF_STATE_PREPARED
;
1276 int vb2_core_prepare_buf(struct vb2_queue
*q
, unsigned int index
, void *pb
)
1278 struct vb2_buffer
*vb
;
1281 vb
= q
->bufs
[index
];
1282 if (vb
->state
!= VB2_BUF_STATE_DEQUEUED
) {
1283 dprintk(1, "invalid buffer state %d\n",
1288 ret
= __buf_prepare(vb
, pb
);
1292 /* Fill buffer information for the userspace */
1293 call_void_bufop(q
, fill_user_buffer
, vb
, pb
);
1295 dprintk(1, "prepare of buffer %d succeeded\n", vb
->index
);
1299 EXPORT_SYMBOL_GPL(vb2_core_prepare_buf
);
1302 * vb2_start_streaming() - Attempt to start streaming.
1303 * @q: videobuf2 queue
1305 * Attempt to start streaming. When this function is called there must be
1306 * at least q->min_buffers_needed buffers queued up (i.e. the minimum
1307 * number of buffers required for the DMA engine to function). If the
1308 * @start_streaming op fails it is supposed to return all the driver-owned
1309 * buffers back to vb2 in state QUEUED. Check if that happened and if
1310 * not warn and reclaim them forcefully.
1312 static int vb2_start_streaming(struct vb2_queue
*q
)
1314 struct vb2_buffer
*vb
;
1318 * If any buffers were queued before streamon,
1319 * we can now pass them to driver for processing.
1321 list_for_each_entry(vb
, &q
->queued_list
, queued_entry
)
1322 __enqueue_in_driver(vb
);
1324 /* Tell the driver to start streaming */
1325 q
->start_streaming_called
= 1;
1326 ret
= call_qop(q
, start_streaming
, q
,
1327 atomic_read(&q
->owned_by_drv_count
));
1331 q
->start_streaming_called
= 0;
1333 dprintk(1, "driver refused to start streaming\n");
1335 * If you see this warning, then the driver isn't cleaning up properly
1336 * after a failed start_streaming(). See the start_streaming()
1337 * documentation in videobuf2-core.h for more information how buffers
1338 * should be returned to vb2 in start_streaming().
1340 if (WARN_ON(atomic_read(&q
->owned_by_drv_count
))) {
1344 * Forcefully reclaim buffers if the driver did not
1345 * correctly return them to vb2.
1347 for (i
= 0; i
< q
->num_buffers
; ++i
) {
1349 if (vb
->state
== VB2_BUF_STATE_ACTIVE
)
1350 vb2_buffer_done(vb
, VB2_BUF_STATE_QUEUED
);
1352 /* Must be zero now */
1353 WARN_ON(atomic_read(&q
->owned_by_drv_count
));
1356 * If done_list is not empty, then start_streaming() didn't call
1357 * vb2_buffer_done(vb, VB2_BUF_STATE_QUEUED) but STATE_ERROR or
1360 WARN_ON(!list_empty(&q
->done_list
));
1364 int vb2_core_qbuf(struct vb2_queue
*q
, unsigned int index
, void *pb
)
1366 struct vb2_buffer
*vb
;
1369 vb
= q
->bufs
[index
];
1371 switch (vb
->state
) {
1372 case VB2_BUF_STATE_DEQUEUED
:
1373 ret
= __buf_prepare(vb
, pb
);
1377 case VB2_BUF_STATE_PREPARED
:
1379 case VB2_BUF_STATE_PREPARING
:
1380 dprintk(1, "buffer still being prepared\n");
1383 dprintk(1, "invalid buffer state %d\n", vb
->state
);
1388 * Add to the queued buffers list, a buffer will stay on it until
1389 * dequeued in dqbuf.
1391 list_add_tail(&vb
->queued_entry
, &q
->queued_list
);
1393 q
->waiting_for_buffers
= false;
1394 vb
->state
= VB2_BUF_STATE_QUEUED
;
1397 call_void_bufop(q
, copy_timestamp
, vb
, pb
);
1399 trace_vb2_qbuf(q
, vb
);
1402 * If already streaming, give the buffer to driver for processing.
1403 * If not, the buffer will be given to driver on next streamon.
1405 if (q
->start_streaming_called
)
1406 __enqueue_in_driver(vb
);
1408 /* Fill buffer information for the userspace */
1410 call_void_bufop(q
, fill_user_buffer
, vb
, pb
);
1413 * If streamon has been called, and we haven't yet called
1414 * start_streaming() since not enough buffers were queued, and
1415 * we now have reached the minimum number of queued buffers,
1416 * then we can finally call start_streaming().
1418 if (q
->streaming
&& !q
->start_streaming_called
&&
1419 q
->queued_count
>= q
->min_buffers_needed
) {
1420 ret
= vb2_start_streaming(q
);
1425 dprintk(1, "qbuf of buffer %d succeeded\n", vb
->index
);
1428 EXPORT_SYMBOL_GPL(vb2_core_qbuf
);
1431 * __vb2_wait_for_done_vb() - wait for a buffer to become available
1434 * Will sleep if required for nonblocking == false.
1436 static int __vb2_wait_for_done_vb(struct vb2_queue
*q
, int nonblocking
)
1439 * All operations on vb_done_list are performed under done_lock
1440 * spinlock protection. However, buffers may be removed from
1441 * it and returned to userspace only while holding both driver's
1442 * lock and the done_lock spinlock. Thus we can be sure that as
1443 * long as we hold the driver's lock, the list will remain not
1444 * empty if list_empty() check succeeds.
1450 if (!q
->streaming
) {
1451 dprintk(1, "streaming off, will not wait for buffers\n");
1456 dprintk(1, "Queue in error state, will not wait for buffers\n");
1460 if (q
->last_buffer_dequeued
) {
1461 dprintk(3, "last buffer dequeued already, will not wait for buffers\n");
1465 if (!list_empty(&q
->done_list
)) {
1467 * Found a buffer that we were waiting for.
1473 dprintk(1, "nonblocking and no buffers to dequeue, will not wait\n");
1478 * We are streaming and blocking, wait for another buffer to
1479 * become ready or for streamoff. Driver's lock is released to
1480 * allow streamoff or qbuf to be called while waiting.
1482 call_void_qop(q
, wait_prepare
, q
);
1485 * All locks have been released, it is safe to sleep now.
1487 dprintk(3, "will sleep waiting for buffers\n");
1488 ret
= wait_event_interruptible(q
->done_wq
,
1489 !list_empty(&q
->done_list
) || !q
->streaming
||
1493 * We need to reevaluate both conditions again after reacquiring
1494 * the locks or return an error if one occurred.
1496 call_void_qop(q
, wait_finish
, q
);
1498 dprintk(1, "sleep was interrupted\n");
1506 * __vb2_get_done_vb() - get a buffer ready for dequeuing
1508 * Will sleep if required for nonblocking == false.
1510 static int __vb2_get_done_vb(struct vb2_queue
*q
, struct vb2_buffer
**vb
,
1511 void *pb
, int nonblocking
)
1513 unsigned long flags
;
1517 * Wait for at least one buffer to become available on the done_list.
1519 ret
= __vb2_wait_for_done_vb(q
, nonblocking
);
1524 * Driver's lock has been held since we last verified that done_list
1525 * is not empty, so no need for another list_empty(done_list) check.
1527 spin_lock_irqsave(&q
->done_lock
, flags
);
1528 *vb
= list_first_entry(&q
->done_list
, struct vb2_buffer
, done_entry
);
1530 * Only remove the buffer from done_list if all planes can be
1531 * handled. Some cases such as V4L2 file I/O and DVB have pb
1532 * == NULL; skip the check then as there's nothing to verify.
1535 ret
= call_bufop(q
, verify_planes_array
, *vb
, pb
);
1537 list_del(&(*vb
)->done_entry
);
1538 spin_unlock_irqrestore(&q
->done_lock
, flags
);
1543 int vb2_wait_for_all_buffers(struct vb2_queue
*q
)
1545 if (!q
->streaming
) {
1546 dprintk(1, "streaming off, will not wait for buffers\n");
1550 if (q
->start_streaming_called
)
1551 wait_event(q
->done_wq
, !atomic_read(&q
->owned_by_drv_count
));
1554 EXPORT_SYMBOL_GPL(vb2_wait_for_all_buffers
);
1557 * __vb2_dqbuf() - bring back the buffer to the DEQUEUED state
1559 static void __vb2_dqbuf(struct vb2_buffer
*vb
)
1561 struct vb2_queue
*q
= vb
->vb2_queue
;
1564 /* nothing to do if the buffer is already dequeued */
1565 if (vb
->state
== VB2_BUF_STATE_DEQUEUED
)
1568 vb
->state
= VB2_BUF_STATE_DEQUEUED
;
1570 /* unmap DMABUF buffer */
1571 if (q
->memory
== VB2_MEMORY_DMABUF
)
1572 for (i
= 0; i
< vb
->num_planes
; ++i
) {
1573 if (!vb
->planes
[i
].dbuf_mapped
)
1575 call_void_memop(vb
, unmap_dmabuf
, vb
->planes
[i
].mem_priv
);
1576 vb
->planes
[i
].dbuf_mapped
= 0;
1580 int vb2_core_dqbuf(struct vb2_queue
*q
, unsigned int *pindex
, void *pb
,
1583 struct vb2_buffer
*vb
= NULL
;
1586 ret
= __vb2_get_done_vb(q
, &vb
, pb
, nonblocking
);
1590 switch (vb
->state
) {
1591 case VB2_BUF_STATE_DONE
:
1592 dprintk(3, "returning done buffer\n");
1594 case VB2_BUF_STATE_ERROR
:
1595 dprintk(3, "returning done buffer with errors\n");
1598 dprintk(1, "invalid buffer state\n");
1602 call_void_vb_qop(vb
, buf_finish
, vb
);
1605 *pindex
= vb
->index
;
1607 /* Fill buffer information for the userspace */
1609 call_void_bufop(q
, fill_user_buffer
, vb
, pb
);
1611 /* Remove from videobuf queue */
1612 list_del(&vb
->queued_entry
);
1615 trace_vb2_dqbuf(q
, vb
);
1617 /* go back to dequeued state */
1620 dprintk(1, "dqbuf of buffer %d, with state %d\n",
1621 vb
->index
, vb
->state
);
1626 EXPORT_SYMBOL_GPL(vb2_core_dqbuf
);
1629 * __vb2_queue_cancel() - cancel and stop (pause) streaming
1631 * Removes all queued buffers from driver's queue and all buffers queued by
1632 * userspace from videobuf's queue. Returns to state after reqbufs.
1634 static void __vb2_queue_cancel(struct vb2_queue
*q
)
1639 * Tell driver to stop all transactions and release all queued
1642 if (q
->start_streaming_called
)
1643 call_void_qop(q
, stop_streaming
, q
);
1646 * If you see this warning, then the driver isn't cleaning up properly
1647 * in stop_streaming(). See the stop_streaming() documentation in
1648 * videobuf2-core.h for more information how buffers should be returned
1649 * to vb2 in stop_streaming().
1651 if (WARN_ON(atomic_read(&q
->owned_by_drv_count
))) {
1652 for (i
= 0; i
< q
->num_buffers
; ++i
)
1653 if (q
->bufs
[i
]->state
== VB2_BUF_STATE_ACTIVE
)
1654 vb2_buffer_done(q
->bufs
[i
], VB2_BUF_STATE_ERROR
);
1655 /* Must be zero now */
1656 WARN_ON(atomic_read(&q
->owned_by_drv_count
));
1660 q
->start_streaming_called
= 0;
1661 q
->queued_count
= 0;
1665 * Remove all buffers from videobuf's list...
1667 INIT_LIST_HEAD(&q
->queued_list
);
1669 * ...and done list; userspace will not receive any buffers it
1670 * has not already dequeued before initiating cancel.
1672 INIT_LIST_HEAD(&q
->done_list
);
1673 atomic_set(&q
->owned_by_drv_count
, 0);
1674 wake_up_all(&q
->done_wq
);
1677 * Reinitialize all buffers for next use.
1678 * Make sure to call buf_finish for any queued buffers. Normally
1679 * that's done in dqbuf, but that's not going to happen when we
1680 * cancel the whole queue. Note: this code belongs here, not in
1681 * __vb2_dqbuf() since in vb2_core_dqbuf() there is a critical
1682 * call to __fill_user_buffer() after buf_finish(). That order can't
1683 * be changed, so we can't move the buf_finish() to __vb2_dqbuf().
1685 for (i
= 0; i
< q
->num_buffers
; ++i
) {
1686 struct vb2_buffer
*vb
= q
->bufs
[i
];
1688 if (vb
->state
!= VB2_BUF_STATE_DEQUEUED
) {
1689 vb
->state
= VB2_BUF_STATE_PREPARED
;
1690 call_void_vb_qop(vb
, buf_finish
, vb
);
1696 int vb2_core_streamon(struct vb2_queue
*q
, unsigned int type
)
1700 if (type
!= q
->type
) {
1701 dprintk(1, "invalid stream type\n");
1706 dprintk(3, "already streaming\n");
1710 if (!q
->num_buffers
) {
1711 dprintk(1, "no buffers have been allocated\n");
1715 if (q
->num_buffers
< q
->min_buffers_needed
) {
1716 dprintk(1, "need at least %u allocated buffers\n",
1717 q
->min_buffers_needed
);
1722 * Tell driver to start streaming provided sufficient buffers
1725 if (q
->queued_count
>= q
->min_buffers_needed
) {
1726 ret
= v4l_vb2q_enable_media_source(q
);
1729 ret
= vb2_start_streaming(q
);
1731 __vb2_queue_cancel(q
);
1738 dprintk(3, "successful\n");
1741 EXPORT_SYMBOL_GPL(vb2_core_streamon
);
1743 void vb2_queue_error(struct vb2_queue
*q
)
1747 wake_up_all(&q
->done_wq
);
1749 EXPORT_SYMBOL_GPL(vb2_queue_error
);
1751 int vb2_core_streamoff(struct vb2_queue
*q
, unsigned int type
)
1753 if (type
!= q
->type
) {
1754 dprintk(1, "invalid stream type\n");
1759 * Cancel will pause streaming and remove all buffers from the driver
1760 * and videobuf, effectively returning control over them to userspace.
1762 * Note that we do this even if q->streaming == 0: if you prepare or
1763 * queue buffers, and then call streamoff without ever having called
1764 * streamon, you would still expect those buffers to be returned to
1765 * their normal dequeued state.
1767 __vb2_queue_cancel(q
);
1768 q
->waiting_for_buffers
= !q
->is_output
;
1769 q
->last_buffer_dequeued
= false;
1771 dprintk(3, "successful\n");
1774 EXPORT_SYMBOL_GPL(vb2_core_streamoff
);
1777 * __find_plane_by_offset() - find plane associated with the given offset off
1779 static int __find_plane_by_offset(struct vb2_queue
*q
, unsigned long off
,
1780 unsigned int *_buffer
, unsigned int *_plane
)
1782 struct vb2_buffer
*vb
;
1783 unsigned int buffer
, plane
;
1786 * Go over all buffers and their planes, comparing the given offset
1787 * with an offset assigned to each plane. If a match is found,
1788 * return its buffer and plane numbers.
1790 for (buffer
= 0; buffer
< q
->num_buffers
; ++buffer
) {
1791 vb
= q
->bufs
[buffer
];
1793 for (plane
= 0; plane
< vb
->num_planes
; ++plane
) {
1794 if (vb
->planes
[plane
].m
.offset
== off
) {
1805 int vb2_core_expbuf(struct vb2_queue
*q
, int *fd
, unsigned int type
,
1806 unsigned int index
, unsigned int plane
, unsigned int flags
)
1808 struct vb2_buffer
*vb
= NULL
;
1809 struct vb2_plane
*vb_plane
;
1811 struct dma_buf
*dbuf
;
1813 if (q
->memory
!= VB2_MEMORY_MMAP
) {
1814 dprintk(1, "queue is not currently set up for mmap\n");
1818 if (!q
->mem_ops
->get_dmabuf
) {
1819 dprintk(1, "queue does not support DMA buffer exporting\n");
1823 if (flags
& ~(O_CLOEXEC
| O_ACCMODE
)) {
1824 dprintk(1, "queue does support only O_CLOEXEC and access mode flags\n");
1828 if (type
!= q
->type
) {
1829 dprintk(1, "invalid buffer type\n");
1833 if (index
>= q
->num_buffers
) {
1834 dprintk(1, "buffer index out of range\n");
1838 vb
= q
->bufs
[index
];
1840 if (plane
>= vb
->num_planes
) {
1841 dprintk(1, "buffer plane out of range\n");
1845 if (vb2_fileio_is_active(q
)) {
1846 dprintk(1, "expbuf: file io in progress\n");
1850 vb_plane
= &vb
->planes
[plane
];
1852 dbuf
= call_ptr_memop(vb
, get_dmabuf
, vb_plane
->mem_priv
,
1854 if (IS_ERR_OR_NULL(dbuf
)) {
1855 dprintk(1, "failed to export buffer %d, plane %d\n",
1860 ret
= dma_buf_fd(dbuf
, flags
& ~O_ACCMODE
);
1862 dprintk(3, "buffer %d, plane %d failed to export (%d)\n",
1868 dprintk(3, "buffer %d, plane %d exported as %d descriptor\n",
1874 EXPORT_SYMBOL_GPL(vb2_core_expbuf
);
1876 int vb2_mmap(struct vb2_queue
*q
, struct vm_area_struct
*vma
)
1878 unsigned long off
= vma
->vm_pgoff
<< PAGE_SHIFT
;
1879 struct vb2_buffer
*vb
;
1880 unsigned int buffer
= 0, plane
= 0;
1882 unsigned long length
;
1884 if (q
->memory
!= VB2_MEMORY_MMAP
) {
1885 dprintk(1, "queue is not currently set up for mmap\n");
1890 * Check memory area access mode.
1892 if (!(vma
->vm_flags
& VM_SHARED
)) {
1893 dprintk(1, "invalid vma flags, VM_SHARED needed\n");
1897 if (!(vma
->vm_flags
& VM_WRITE
)) {
1898 dprintk(1, "invalid vma flags, VM_WRITE needed\n");
1902 if (!(vma
->vm_flags
& VM_READ
)) {
1903 dprintk(1, "invalid vma flags, VM_READ needed\n");
1907 if (vb2_fileio_is_active(q
)) {
1908 dprintk(1, "mmap: file io in progress\n");
1913 * Find the plane corresponding to the offset passed by userspace.
1915 ret
= __find_plane_by_offset(q
, off
, &buffer
, &plane
);
1919 vb
= q
->bufs
[buffer
];
1922 * MMAP requires page_aligned buffers.
1923 * The buffer length was page_aligned at __vb2_buf_mem_alloc(),
1924 * so, we need to do the same here.
1926 length
= PAGE_ALIGN(vb
->planes
[plane
].length
);
1927 if (length
< (vma
->vm_end
- vma
->vm_start
)) {
1929 "MMAP invalid, as it would overflow buffer length\n");
1933 mutex_lock(&q
->mmap_lock
);
1934 ret
= call_memop(vb
, mmap
, vb
->planes
[plane
].mem_priv
, vma
);
1935 mutex_unlock(&q
->mmap_lock
);
1939 dprintk(3, "buffer %d, plane %d successfully mapped\n", buffer
, plane
);
1942 EXPORT_SYMBOL_GPL(vb2_mmap
);
1945 unsigned long vb2_get_unmapped_area(struct vb2_queue
*q
,
1948 unsigned long pgoff
,
1949 unsigned long flags
)
1951 unsigned long off
= pgoff
<< PAGE_SHIFT
;
1952 struct vb2_buffer
*vb
;
1953 unsigned int buffer
, plane
;
1957 if (q
->memory
!= VB2_MEMORY_MMAP
) {
1958 dprintk(1, "queue is not currently set up for mmap\n");
1963 * Find the plane corresponding to the offset passed by userspace.
1965 ret
= __find_plane_by_offset(q
, off
, &buffer
, &plane
);
1969 vb
= q
->bufs
[buffer
];
1971 vaddr
= vb2_plane_vaddr(vb
, plane
);
1972 return vaddr
? (unsigned long)vaddr
: -EINVAL
;
1974 EXPORT_SYMBOL_GPL(vb2_get_unmapped_area
);
1977 int vb2_core_queue_init(struct vb2_queue
*q
)
1984 WARN_ON(!q
->mem_ops
) ||
1985 WARN_ON(!q
->type
) ||
1986 WARN_ON(!q
->io_modes
) ||
1987 WARN_ON(!q
->ops
->queue_setup
) ||
1988 WARN_ON(!q
->ops
->buf_queue
))
1991 INIT_LIST_HEAD(&q
->queued_list
);
1992 INIT_LIST_HEAD(&q
->done_list
);
1993 spin_lock_init(&q
->done_lock
);
1994 mutex_init(&q
->mmap_lock
);
1995 init_waitqueue_head(&q
->done_wq
);
1997 if (q
->buf_struct_size
== 0)
1998 q
->buf_struct_size
= sizeof(struct vb2_buffer
);
2002 EXPORT_SYMBOL_GPL(vb2_core_queue_init
);
2004 static int __vb2_init_fileio(struct vb2_queue
*q
, int read
);
2005 static int __vb2_cleanup_fileio(struct vb2_queue
*q
);
2006 void vb2_core_queue_release(struct vb2_queue
*q
)
2008 __vb2_cleanup_fileio(q
);
2009 __vb2_queue_cancel(q
);
2010 mutex_lock(&q
->mmap_lock
);
2011 __vb2_queue_free(q
, q
->num_buffers
);
2012 mutex_unlock(&q
->mmap_lock
);
2014 EXPORT_SYMBOL_GPL(vb2_core_queue_release
);
2016 unsigned int vb2_core_poll(struct vb2_queue
*q
, struct file
*file
,
2019 unsigned long req_events
= poll_requested_events(wait
);
2020 struct vb2_buffer
*vb
= NULL
;
2021 unsigned long flags
;
2023 if (!q
->is_output
&& !(req_events
& (POLLIN
| POLLRDNORM
)))
2025 if (q
->is_output
&& !(req_events
& (POLLOUT
| POLLWRNORM
)))
2029 * Start file I/O emulator only if streaming API has not been used yet.
2031 if (q
->num_buffers
== 0 && !vb2_fileio_is_active(q
)) {
2032 if (!q
->is_output
&& (q
->io_modes
& VB2_READ
) &&
2033 (req_events
& (POLLIN
| POLLRDNORM
))) {
2034 if (__vb2_init_fileio(q
, 1))
2037 if (q
->is_output
&& (q
->io_modes
& VB2_WRITE
) &&
2038 (req_events
& (POLLOUT
| POLLWRNORM
))) {
2039 if (__vb2_init_fileio(q
, 0))
2042 * Write to OUTPUT queue can be done immediately.
2044 return POLLOUT
| POLLWRNORM
;
2049 * There is nothing to wait for if the queue isn't streaming, or if the
2050 * error flag is set.
2052 if (!vb2_is_streaming(q
) || q
->error
)
2056 * If this quirk is set and QBUF hasn't been called yet then
2057 * return POLLERR as well. This only affects capture queues, output
2058 * queues will always initialize waiting_for_buffers to false.
2059 * This quirk is set by V4L2 for backwards compatibility reasons.
2061 if (q
->quirk_poll_must_check_waiting_for_buffers
&&
2062 q
->waiting_for_buffers
&& (req_events
& (POLLIN
| POLLRDNORM
)))
2066 * For output streams you can call write() as long as there are fewer
2067 * buffers queued than there are buffers available.
2069 if (q
->is_output
&& q
->fileio
&& q
->queued_count
< q
->num_buffers
)
2070 return POLLOUT
| POLLWRNORM
;
2072 if (list_empty(&q
->done_list
)) {
2074 * If the last buffer was dequeued from a capture queue,
2075 * return immediately. DQBUF will return -EPIPE.
2077 if (q
->last_buffer_dequeued
)
2078 return POLLIN
| POLLRDNORM
;
2080 poll_wait(file
, &q
->done_wq
, wait
);
2084 * Take first buffer available for dequeuing.
2086 spin_lock_irqsave(&q
->done_lock
, flags
);
2087 if (!list_empty(&q
->done_list
))
2088 vb
= list_first_entry(&q
->done_list
, struct vb2_buffer
,
2090 spin_unlock_irqrestore(&q
->done_lock
, flags
);
2092 if (vb
&& (vb
->state
== VB2_BUF_STATE_DONE
2093 || vb
->state
== VB2_BUF_STATE_ERROR
)) {
2094 return (q
->is_output
) ?
2095 POLLOUT
| POLLWRNORM
:
2096 POLLIN
| POLLRDNORM
;
2100 EXPORT_SYMBOL_GPL(vb2_core_poll
);
2103 * struct vb2_fileio_buf - buffer context used by file io emulator
2105 * vb2 provides a compatibility layer and emulator of file io (read and
2106 * write) calls on top of streaming API. This structure is used for
2107 * tracking context related to the buffers.
2109 struct vb2_fileio_buf
{
2113 unsigned int queued
:1;
2117 * struct vb2_fileio_data - queue context used by file io emulator
2119 * @cur_index: the index of the buffer currently being read from or
2120 * written to. If equal to q->num_buffers then a new buffer
2122 * @initial_index: in the read() case all buffers are queued up immediately
2123 * in __vb2_init_fileio() and __vb2_perform_fileio() just cycles
2124 * buffers. However, in the write() case no buffers are initially
2125 * queued, instead whenever a buffer is full it is queued up by
2126 * __vb2_perform_fileio(). Only once all available buffers have
2127 * been queued up will __vb2_perform_fileio() start to dequeue
2128 * buffers. This means that initially __vb2_perform_fileio()
2129 * needs to know what buffer index to use when it is queuing up
2130 * the buffers for the first time. That initial index is stored
2131 * in this field. Once it is equal to q->num_buffers all
2132 * available buffers have been queued and __vb2_perform_fileio()
2133 * should start the normal dequeue/queue cycle.
2135 * vb2 provides a compatibility layer and emulator of file io (read and
2136 * write) calls on top of streaming API. For proper operation it required
2137 * this structure to save the driver state between each call of the read
2138 * or write function.
2140 struct vb2_fileio_data
{
2143 unsigned int memory
;
2144 struct vb2_fileio_buf bufs
[VB2_MAX_FRAME
];
2145 unsigned int cur_index
;
2146 unsigned int initial_index
;
2147 unsigned int q_count
;
2148 unsigned int dq_count
;
2149 unsigned read_once
:1;
2150 unsigned write_immediately
:1;
2154 * __vb2_init_fileio() - initialize file io emulator
2155 * @q: videobuf2 queue
2156 * @read: mode selector (1 means read, 0 means write)
2158 static int __vb2_init_fileio(struct vb2_queue
*q
, int read
)
2160 struct vb2_fileio_data
*fileio
;
2162 unsigned int count
= 0;
2167 if (WARN_ON((read
&& !(q
->io_modes
& VB2_READ
)) ||
2168 (!read
&& !(q
->io_modes
& VB2_WRITE
))))
2172 * Check if device supports mapping buffers to kernel virtual space.
2174 if (!q
->mem_ops
->vaddr
)
2178 * Check if streaming api has not been already activated.
2180 if (q
->streaming
|| q
->num_buffers
> 0)
2184 * Start with count 1, driver can increase it in queue_setup()
2188 dprintk(3, "setting up file io: mode %s, count %d, read_once %d, write_immediately %d\n",
2189 (read
) ? "read" : "write", count
, q
->fileio_read_once
,
2190 q
->fileio_write_immediately
);
2192 fileio
= kzalloc(sizeof(*fileio
), GFP_KERNEL
);
2196 fileio
->read_once
= q
->fileio_read_once
;
2197 fileio
->write_immediately
= q
->fileio_write_immediately
;
2200 * Request buffers and use MMAP type to force driver
2201 * to allocate buffers by itself.
2203 fileio
->count
= count
;
2204 fileio
->memory
= VB2_MEMORY_MMAP
;
2205 fileio
->type
= q
->type
;
2207 ret
= vb2_core_reqbufs(q
, fileio
->memory
, &fileio
->count
);
2212 * Check if plane_count is correct
2213 * (multiplane buffers are not supported).
2215 if (q
->bufs
[0]->num_planes
!= 1) {
2221 * Get kernel address of each buffer.
2223 for (i
= 0; i
< q
->num_buffers
; i
++) {
2224 fileio
->bufs
[i
].vaddr
= vb2_plane_vaddr(q
->bufs
[i
], 0);
2225 if (fileio
->bufs
[i
].vaddr
== NULL
) {
2229 fileio
->bufs
[i
].size
= vb2_plane_size(q
->bufs
[i
], 0);
2233 * Read mode requires pre queuing of all buffers.
2237 * Queue all buffers.
2239 for (i
= 0; i
< q
->num_buffers
; i
++) {
2240 ret
= vb2_core_qbuf(q
, i
, NULL
);
2243 fileio
->bufs
[i
].queued
= 1;
2246 * All buffers have been queued, so mark that by setting
2247 * initial_index to q->num_buffers
2249 fileio
->initial_index
= q
->num_buffers
;
2250 fileio
->cur_index
= q
->num_buffers
;
2256 ret
= vb2_core_streamon(q
, q
->type
);
2264 vb2_core_reqbufs(q
, fileio
->memory
, &fileio
->count
);
2273 * __vb2_cleanup_fileio() - free resourced used by file io emulator
2274 * @q: videobuf2 queue
2276 static int __vb2_cleanup_fileio(struct vb2_queue
*q
)
2278 struct vb2_fileio_data
*fileio
= q
->fileio
;
2281 vb2_core_streamoff(q
, q
->type
);
2284 vb2_core_reqbufs(q
, fileio
->memory
, &fileio
->count
);
2286 dprintk(3, "file io emulator closed\n");
2292 * __vb2_perform_fileio() - perform a single file io (read or write) operation
2293 * @q: videobuf2 queue
2294 * @data: pointed to target userspace buffer
2295 * @count: number of bytes to read or write
2296 * @ppos: file handle position tracking pointer
2297 * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking)
2298 * @read: access mode selector (1 means read, 0 means write)
2300 static size_t __vb2_perform_fileio(struct vb2_queue
*q
, char __user
*data
, size_t count
,
2301 loff_t
*ppos
, int nonblock
, int read
)
2303 struct vb2_fileio_data
*fileio
;
2304 struct vb2_fileio_buf
*buf
;
2305 bool is_multiplanar
= q
->is_multiplanar
;
2307 * When using write() to write data to an output video node the vb2 core
2308 * should copy timestamps if V4L2_BUF_FLAG_TIMESTAMP_COPY is set. Nobody
2309 * else is able to provide this information with the write() operation.
2311 bool copy_timestamp
= !read
&& q
->copy_timestamp
;
2315 dprintk(3, "mode %s, offset %ld, count %zd, %sblocking\n",
2316 read
? "read" : "write", (long)*ppos
, count
,
2317 nonblock
? "non" : "");
2323 * Initialize emulator on first call.
2325 if (!vb2_fileio_is_active(q
)) {
2326 ret
= __vb2_init_fileio(q
, read
);
2327 dprintk(3, "vb2_init_fileio result: %d\n", ret
);
2334 * Check if we need to dequeue the buffer.
2336 index
= fileio
->cur_index
;
2337 if (index
>= q
->num_buffers
) {
2338 struct vb2_buffer
*b
;
2341 * Call vb2_dqbuf to get buffer back.
2343 ret
= vb2_core_dqbuf(q
, &index
, NULL
, nonblock
);
2344 dprintk(5, "vb2_dqbuf result: %d\n", ret
);
2347 fileio
->dq_count
+= 1;
2349 fileio
->cur_index
= index
;
2350 buf
= &fileio
->bufs
[index
];
2354 * Get number of bytes filled by the driver
2358 buf
->size
= read
? vb2_get_plane_payload(q
->bufs
[index
], 0)
2359 : vb2_plane_size(q
->bufs
[index
], 0);
2360 /* Compensate for data_offset on read in the multiplanar case. */
2361 if (is_multiplanar
&& read
&&
2362 b
->planes
[0].data_offset
< buf
->size
) {
2363 buf
->pos
= b
->planes
[0].data_offset
;
2364 buf
->size
-= buf
->pos
;
2367 buf
= &fileio
->bufs
[index
];
2371 * Limit count on last few bytes of the buffer.
2373 if (buf
->pos
+ count
> buf
->size
) {
2374 count
= buf
->size
- buf
->pos
;
2375 dprintk(5, "reducing read count: %zd\n", count
);
2379 * Transfer data to userspace.
2381 dprintk(3, "copying %zd bytes - buffer %d, offset %u\n",
2382 count
, index
, buf
->pos
);
2384 ret
= copy_to_user(data
, buf
->vaddr
+ buf
->pos
, count
);
2386 ret
= copy_from_user(buf
->vaddr
+ buf
->pos
, data
, count
);
2388 dprintk(3, "error copying data\n");
2399 * Queue next buffer if required.
2401 if (buf
->pos
== buf
->size
|| (!read
&& fileio
->write_immediately
)) {
2402 struct vb2_buffer
*b
= q
->bufs
[index
];
2405 * Check if this is the last buffer to read.
2407 if (read
&& fileio
->read_once
&& fileio
->dq_count
== 1) {
2408 dprintk(3, "read limit reached\n");
2409 return __vb2_cleanup_fileio(q
);
2413 * Call vb2_qbuf and give buffer to the driver.
2415 b
->planes
[0].bytesused
= buf
->pos
;
2418 b
->timestamp
= ktime_get_ns();
2419 ret
= vb2_core_qbuf(q
, index
, NULL
);
2420 dprintk(5, "vb2_dbuf result: %d\n", ret
);
2425 * Buffer has been queued, update the status
2429 buf
->size
= vb2_plane_size(q
->bufs
[index
], 0);
2430 fileio
->q_count
+= 1;
2432 * If we are queuing up buffers for the first time, then
2433 * increase initial_index by one.
2435 if (fileio
->initial_index
< q
->num_buffers
)
2436 fileio
->initial_index
++;
2438 * The next buffer to use is either a buffer that's going to be
2439 * queued for the first time (initial_index < q->num_buffers)
2440 * or it is equal to q->num_buffers, meaning that the next
2441 * time we need to dequeue a buffer since we've now queued up
2442 * all the 'first time' buffers.
2444 fileio
->cur_index
= fileio
->initial_index
;
2448 * Return proper number of bytes processed.
2455 size_t vb2_read(struct vb2_queue
*q
, char __user
*data
, size_t count
,
2456 loff_t
*ppos
, int nonblocking
)
2458 return __vb2_perform_fileio(q
, data
, count
, ppos
, nonblocking
, 1);
2460 EXPORT_SYMBOL_GPL(vb2_read
);
2462 size_t vb2_write(struct vb2_queue
*q
, const char __user
*data
, size_t count
,
2463 loff_t
*ppos
, int nonblocking
)
2465 return __vb2_perform_fileio(q
, (char __user
*) data
, count
,
2466 ppos
, nonblocking
, 0);
2468 EXPORT_SYMBOL_GPL(vb2_write
);
2470 struct vb2_threadio_data
{
2471 struct task_struct
*thread
;
2477 static int vb2_thread(void *data
)
2479 struct vb2_queue
*q
= data
;
2480 struct vb2_threadio_data
*threadio
= q
->threadio
;
2481 bool copy_timestamp
= false;
2482 unsigned prequeue
= 0;
2487 prequeue
= q
->num_buffers
;
2488 copy_timestamp
= q
->copy_timestamp
;
2494 struct vb2_buffer
*vb
;
2497 * Call vb2_dqbuf to get buffer back.
2500 vb
= q
->bufs
[index
++];
2503 call_void_qop(q
, wait_finish
, q
);
2504 if (!threadio
->stop
)
2505 ret
= vb2_core_dqbuf(q
, &index
, NULL
, 0);
2506 call_void_qop(q
, wait_prepare
, q
);
2507 dprintk(5, "file io: vb2_dqbuf result: %d\n", ret
);
2509 vb
= q
->bufs
[index
];
2511 if (ret
|| threadio
->stop
)
2515 if (vb
->state
!= VB2_BUF_STATE_ERROR
)
2516 if (threadio
->fnc(vb
, threadio
->priv
))
2518 call_void_qop(q
, wait_finish
, q
);
2520 vb
->timestamp
= ktime_get_ns();;
2521 if (!threadio
->stop
)
2522 ret
= vb2_core_qbuf(q
, vb
->index
, NULL
);
2523 call_void_qop(q
, wait_prepare
, q
);
2524 if (ret
|| threadio
->stop
)
2528 /* Hmm, linux becomes *very* unhappy without this ... */
2529 while (!kthread_should_stop()) {
2530 set_current_state(TASK_INTERRUPTIBLE
);
2537 * This function should not be used for anything else but the videobuf2-dvb
2538 * support. If you think you have another good use-case for this, then please
2539 * contact the linux-media mailinglist first.
2541 int vb2_thread_start(struct vb2_queue
*q
, vb2_thread_fnc fnc
, void *priv
,
2542 const char *thread_name
)
2544 struct vb2_threadio_data
*threadio
;
2551 if (WARN_ON(q
->fileio
))
2554 threadio
= kzalloc(sizeof(*threadio
), GFP_KERNEL
);
2555 if (threadio
== NULL
)
2557 threadio
->fnc
= fnc
;
2558 threadio
->priv
= priv
;
2560 ret
= __vb2_init_fileio(q
, !q
->is_output
);
2561 dprintk(3, "file io: vb2_init_fileio result: %d\n", ret
);
2564 q
->threadio
= threadio
;
2565 threadio
->thread
= kthread_run(vb2_thread
, q
, "vb2-%s", thread_name
);
2566 if (IS_ERR(threadio
->thread
)) {
2567 ret
= PTR_ERR(threadio
->thread
);
2568 threadio
->thread
= NULL
;
2574 __vb2_cleanup_fileio(q
);
2579 EXPORT_SYMBOL_GPL(vb2_thread_start
);
2581 int vb2_thread_stop(struct vb2_queue
*q
)
2583 struct vb2_threadio_data
*threadio
= q
->threadio
;
2586 if (threadio
== NULL
)
2588 threadio
->stop
= true;
2589 /* Wake up all pending sleeps in the thread */
2591 err
= kthread_stop(threadio
->thread
);
2592 __vb2_cleanup_fileio(q
);
2593 threadio
->thread
= NULL
;
2598 EXPORT_SYMBOL_GPL(vb2_thread_stop
);
2600 MODULE_DESCRIPTION("Media buffer core framework");
2601 MODULE_AUTHOR("Pawel Osciak <pawel@osciak.com>, Marek Szyprowski");
2602 MODULE_LICENSE("GPL");