static int __vb2_wait_for_done_vb(struct vb2_queue *q, int nonblocking)
{
for (;;) {
int ret;
if (!q->streaming) {
dprintk(1, "Streaming off, will not wait for buffers\n");
return -EINVAL;
}
if (!list_empty(&q->done_list)) {
break;
}
if (nonblocking) {
dprintk(1, "Nonblocking and no buffers to dequeue, "
"will not wait\n");
return -EAGAIN;
}
call_qop(q, wait_prepare, q);
dprintk(3, "Will sleep waiting for buffers\n");
ret = wait_event_interruptible(q->done_wq,
!list_empty(&q->done_list) || !q->streaming);
call_qop(q, wait_finish, q);
if (ret)
return ret;
}
return 0;
}
/**
* __vb2_wait_for_done_vb() - wait for a buffer to become available
* for dequeuing
*
* Will sleep if required for nonblocking == false.
*/
static int __vb2_wait_for_done_vb(struct vb2_queue *q, int nonblocking)
{
/*
* All operations on vb_done_list are performed under done_lock
* spinlock protection. However, buffers may be removed from
* it and returned to userspace only while holding both driver's
* lock and the done_lock spinlock. Thus we can be sure that as
* long as we hold the driver's lock, the list will remain not
* empty if list_empty() check succeeds.
*/
for (;;) {
int ret;
if (!q->streaming) {
dprintk(1, "Streaming off, will not wait for buffers\n");
return -EINVAL;
}
if (!list_empty(&q->done_list)) {
/*
* Found a buffer that we were waiting for.
*/
break;
}
if (nonblocking) {
dprintk(1, "Nonblocking and no buffers to dequeue, "
"will not wait\n");
return -EAGAIN;
}
/*
* We are streaming and blocking, wait for another buffer to
* become ready or for streamoff. Driver's lock is released to
* allow streamoff or qbuf to be called while waiting.
*/
call_qop(q, wait_prepare, q);
/*
* All locks have been released, it is safe to sleep now.
*/
dprintk(3, "Will sleep waiting for buffers\n");
ret = wait_event_interruptible(q->done_wq,
!list_empty(&q->done_list) || !q->streaming);
/*
* We need to reevaluate both conditions again after reacquiring
* the locks or return an error if one occurred.
*/
call_qop(q, wait_finish, q);
if (ret)
return ret;
}
return 0;
}
/**
* __vb2_queue_cancel() - cancel and stop (pause) streaming
*
* Removes all queued buffers from driver's queue and all buffers queued by
* userspace from videobuf's queue. Returns to state after reqbufs.
*/
static void __vb2_queue_cancel(struct vb2_queue *q)
{
unsigned int i;
/*
* Tell driver to stop all transactions and release all queued
* buffers.
*/
if (q->streaming)
call_qop(q, stop_streaming, q);
q->streaming = 0;
/*
* Remove all buffers from videobuf's list...
*/
INIT_LIST_HEAD(&q->queued_list);
/*
* ...and done list; userspace will not receive any buffers it
* has not already dequeued before initiating cancel.
*/
INIT_LIST_HEAD(&q->done_list);
atomic_set(&q->queued_count, 0);
wake_up_all(&q->done_wq);
/*
* Reinitialize all buffers for next use.
*/
for (i = 0; i < q->num_buffers; ++i)
q->bufs[i]->state = VB2_BUF_STATE_DEQUEUED;
}
int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type)
{
struct vb2_buffer *vb;
int ret;
if (q->fileio) {
dprintk(1, "streamon: file io in progress\n");
return -EBUSY;
}
if (type != q->type) {
dprintk(1, "streamon: invalid stream type\n");
return -EINVAL;
}
if (q->streaming) {
dprintk(1, "streamon: already streaming\n");
return -EBUSY;
}
list_for_each_entry(vb, &q->queued_list, queued_entry)
__enqueue_in_driver(vb);
ret = call_qop(q, start_streaming, q, atomic_read(&q->queued_count));
if (ret) {
dprintk(1, "streamon: driver refused to start streaming\n");
__vb2_queue_cancel(q);
return ret;
}
q->streaming = 1;
dprintk(3, "Streamon successful\n");
return 0;
}
static int __vb2_queue_alloc(struct vb2_queue *q, enum v4l2_memory memory,
unsigned int num_buffers, unsigned int num_planes,
unsigned long plane_sizes[])
{
unsigned int buffer;
struct vb2_buffer *vb;
int ret;
for (buffer = 0; buffer < num_buffers; ++buffer) {
vb = kzalloc(q->buf_struct_size, GFP_KERNEL);
if (!vb) {
dprintk(1, "Memory alloc for buffer struct failed\n");
break;
}
if (V4L2_TYPE_IS_MULTIPLANAR(q->type))
vb->v4l2_buf.length = num_planes;
vb->state = VB2_BUF_STATE_DEQUEUED;
vb->vb2_queue = q;
vb->num_planes = num_planes;
vb->v4l2_buf.index = buffer;
vb->v4l2_buf.type = q->type;
vb->v4l2_buf.memory = memory;
if (memory == V4L2_MEMORY_MMAP) {
ret = __vb2_buf_mem_alloc(vb, plane_sizes);
if (ret) {
dprintk(1, "Failed allocating memory for "
"buffer %d\n", buffer);
kfree(vb);
break;
}
ret = call_qop(q, buf_init, vb);
if (ret) {
dprintk(1, "Buffer %d %p initialization"
" failed\n", buffer, vb);
__vb2_buf_mem_free(vb);
kfree(vb);
break;
}
}
q->bufs[buffer] = vb;
}
q->num_buffers = buffer;
__setup_offsets(q);
dprintk(1, "Allocated %d buffers, %d plane(s) each\n",
q->num_buffers, num_planes);
return buffer;
}
/**
* vb2_streamon - start streaming
* @q: videobuf2 queue
* @type: type argument passed from userspace to vidioc_streamon handler
*
* Should be called from vidioc_streamon handler of a driver.
* This function:
* 1) verifies current state
* 2) starts streaming and passes any previously queued buffers to the driver
*
* The return values from this function are intended to be directly returned
* from vidioc_streamon handler in the driver.
*/
int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type)
{
struct vb2_buffer *vb;
int ret;
if (q->fileio) {
dprintk(1, "streamon: file io in progress\n");
return -EBUSY;
}
if (type != q->type) {
dprintk(1, "streamon: invalid stream type\n");
return -EINVAL;
}
if (q->streaming) {
dprintk(1, "streamon: already streaming\n");
return -EBUSY;
}
/*
* Cannot start streaming on an OUTPUT device if no buffers have
* been queued yet.
*/
if (V4L2_TYPE_IS_OUTPUT(q->type)) {
if (list_empty(&q->queued_list)) {
dprintk(1, "streamon: no output buffers queued\n");
return -EINVAL;
}
}
/*
* Let driver notice that streaming state has been enabled.
*/
ret = call_qop(q, start_streaming, q);
if (ret) {
dprintk(1, "streamon: driver refused to start streaming\n");
return ret;
}
q->streaming = 1;
/*
* If any buffers were queued before streamon,
* we can now pass them to driver for processing.
*/
list_for_each_entry(vb, &q->queued_list, queued_entry)
__enqueue_in_driver(vb);
dprintk(3, "Streamon successful\n");
return 0;
}
/**
* vb2_dqbuf() - Dequeue a buffer to the userspace
* @q: videobuf2 queue
* @b: buffer structure passed from userspace to vidioc_dqbuf handler
* in driver
* @nonblocking: if true, this call will not sleep waiting for a buffer if no
* buffers ready for dequeuing are present. Normally the driver
* would be passing (file->f_flags & O_NONBLOCK) here
*
* Should be called from vidioc_dqbuf ioctl handler of a driver.
* This function:
* 1) verifies the passed buffer,
* 2) calls buf_finish callback in the driver (if provided), in which
* driver can perform any additional operations that may be required before
* returning the buffer to userspace, such as cache sync,
* 3) the buffer struct members are filled with relevant information for
* the userspace.
*
* The return values from this function are intended to be directly returned
* from vidioc_dqbuf handler in driver.
*/
int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking)
{
struct vb2_buffer *vb = NULL;
int ret;
if (q->fileio) {
dprintk(1, "dqbuf: file io in progress\n");
return -EBUSY;
}
if (b->type != q->type) {
dprintk(1, "dqbuf: invalid buffer type\n");
return -EINVAL;
}
ret = __vb2_get_done_vb(q, &vb, nonblocking);
if (ret < 0) {
dprintk(1, "dqbuf: error getting next done buffer\n");
return ret;
}
ret = call_qop(q, buf_finish, vb);
if (ret) {
dprintk(1, "dqbuf: buffer finish failed\n");
return ret;
}
switch (vb->state) {
case VB2_BUF_STATE_DONE:
dprintk(3, "dqbuf: Returning done buffer\n");
break;
case VB2_BUF_STATE_ERROR:
dprintk(3, "dqbuf: Returning done buffer with errors\n");
break;
default:
dprintk(1, "dqbuf: Invalid buffer state\n");
return -EINVAL;
}
/* Fill buffer information for the userspace */
__fill_v4l2_buffer(vb, b);
/* Remove from videobuf queue */
list_del(&vb->queued_entry);
dprintk(1, "dqbuf of buffer %d, with state %d\n",
vb->v4l2_buf.index, vb->state);
vb->state = VB2_BUF_STATE_DEQUEUED;
return 0;
}
static void __vb2_queue_cancel(struct vb2_queue *q)
{
unsigned int i;
if (q->streaming)
call_qop(q, stop_streaming, q);
q->streaming = 0;
INIT_LIST_HEAD(&q->queued_list);
INIT_LIST_HEAD(&q->done_list);
atomic_set(&q->queued_count, 0);
wake_up_all(&q->done_wq);
for (i = 0; i < q->num_buffers; ++i)
q->bufs[i]->state = VB2_BUF_STATE_DEQUEUED;
}
/**
* vb2_qbuf() - Queue a buffer from userspace
* @q: videobuf2 queue
* @b: buffer structure passed from userspace to vidioc_qbuf handler
* in driver
*
* Should be called from vidioc_qbuf ioctl handler of a driver.
* This function:
* 1) verifies the passed buffer,
* 2) calls buf_prepare callback in the driver (if provided), in which
* driver-specific buffer initialization can be performed,
* 3) if streaming is on, queues the buffer in driver by the means of buf_queue
* callback for processing.
*
* The return values from this function are intended to be directly returned
* from vidioc_qbuf handler in driver.
*/
int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b)
{
struct vb2_buffer *vb;
int ret = 0;
if (q->fileio) {
dprintk(1, "qbuf: file io in progress\n");
return -EBUSY;
}
if (b->type != q->type) {
dprintk(1, "qbuf: invalid buffer type\n");
return -EINVAL;
}
if (b->index >= q->num_buffers) {
dprintk(1, "qbuf: buffer index out of range\n");
return -EINVAL;
}
vb = q->bufs[b->index];
if (NULL == vb) {
/* Should never happen */
dprintk(1, "qbuf: buffer is NULL\n");
return -EINVAL;
}
if (b->memory != q->memory) {
dprintk(1, "qbuf: invalid memory type\n");
return -EINVAL;
}
if (vb->state != VB2_BUF_STATE_DEQUEUED) {
dprintk(1, "qbuf: buffer already in use\n");
return -EINVAL;
}
if (q->memory == V4L2_MEMORY_MMAP)
ret = __qbuf_mmap(vb, b);
else if (q->memory == V4L2_MEMORY_USERPTR)
ret = __qbuf_userptr(vb, b);
else {
WARN(1, "Invalid queue type\n");
return -EINVAL;
}
if (ret)
return ret;
ret = call_qop(q, buf_prepare, vb);
if (ret) {
dprintk(1, "qbuf: buffer preparation failed\n");
return ret;
}
/*
* Add to the queued buffers list, a buffer will stay on it until
* dequeued in dqbuf.
*/
list_add_tail(&vb->queued_entry, &q->queued_list);
vb->state = VB2_BUF_STATE_QUEUED;
/*
* If already streaming, give the buffer to driver for processing.
* If not, the buffer will be given to driver on next streamon.
*/
if (q->streaming)
__enqueue_in_driver(vb);
dprintk(1, "qbuf of buffer %d succeeded\n", vb->v4l2_buf.index);
return 0;
}
/**
* __qbuf_userptr() - handle qbuf of a USERPTR buffer
*/
static int __qbuf_userptr(struct vb2_buffer *vb, struct v4l2_buffer *b)
{
struct v4l2_plane planes[VIDEO_MAX_PLANES];
struct vb2_queue *q = vb->vb2_queue;
void *mem_priv;
unsigned int plane;
int ret;
int write = !V4L2_TYPE_IS_OUTPUT(q->type);
/* Verify and copy relevant information provided by the userspace */
ret = __fill_vb2_buffer(vb, b, planes);
if (ret)
return ret;
for (plane = 0; plane < vb->num_planes; ++plane) {
/* Skip the plane if already verified */
if (vb->v4l2_planes[plane].m.userptr == planes[plane].m.userptr
&& vb->v4l2_planes[plane].length == planes[plane].length)
continue;
dprintk(3, "qbuf: userspace address for plane %d changed, "
"reacquiring memory\n", plane);
/* Release previously acquired memory if present */
if (vb->planes[plane].mem_priv)
call_memop(q, plane, put_userptr,
vb->planes[plane].mem_priv);
vb->planes[plane].mem_priv = NULL;
/* Acquire each plane's memory */
if (q->mem_ops->get_userptr) {
mem_priv = q->mem_ops->get_userptr(q->alloc_ctx[plane],
planes[plane].m.userptr,
planes[plane].length,
write);
if (IS_ERR(mem_priv)) {
dprintk(1, "qbuf: failed acquiring userspace "
"memory for plane %d\n", plane);
ret = PTR_ERR(mem_priv);
goto err;
}
vb->planes[plane].mem_priv = mem_priv;
}
}
/*
* Call driver-specific initialization on the newly acquired buffer,
* if provided.
*/
ret = call_qop(q, buf_init, vb);
if (ret) {
dprintk(1, "qbuf: buffer initialization failed\n");
goto err;
}
/*
* Now that everything is in order, copy relevant information
* provided by userspace.
*/
for (plane = 0; plane < vb->num_planes; ++plane)
vb->v4l2_planes[plane] = planes[plane];
return 0;
err:
/* In case of errors, release planes that were already acquired */
for (; plane > 0; --plane) {
call_memop(q, plane, put_userptr,
vb->planes[plane - 1].mem_priv);
vb->planes[plane - 1].mem_priv = NULL;
}
return ret;
}
/**
* vb2_reqbufs() - Initiate streaming
* @q: videobuf2 queue
* @req: struct passed from userspace to vidioc_reqbufs handler in driver
*
* Should be called from vidioc_reqbufs ioctl handler of a driver.
* This function:
* 1) verifies streaming parameters passed from the userspace,
* 2) sets up the queue,
* 3) negotiates number of buffers and planes per buffer with the driver
* to be used during streaming,
* 4) allocates internal buffer structures (struct vb2_buffer), according to
* the agreed parameters,
* 5) for MMAP memory type, allocates actual video memory, using the
* memory handling/allocation routines provided during queue initialization
*
* If req->count is 0, all the memory will be freed instead.
* If the queue has been allocated previously (by a previous vb2_reqbufs) call
* and the queue is not busy, memory will be reallocated.
*
* The return values from this function are intended to be directly returned
* from vidioc_reqbufs handler in driver.
*/
int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
{
unsigned int num_buffers = 0;
unsigned int num_planes = 0;
unsigned long plane_sizes[VIDEO_MAX_PLANES];
int ret = 0;
if (q->fileio) {
dprintk(1, "reqbufs: file io in progress\n");
return -EBUSY;
}
if (req->memory != V4L2_MEMORY_MMAP
&& req->memory != V4L2_MEMORY_USERPTR) {
dprintk(1, "reqbufs: unsupported memory type\n");
return -EINVAL;
}
if (req->type != q->type) {
dprintk(1, "reqbufs: requested type is incorrect\n");
return -EINVAL;
}
if (q->streaming) {
dprintk(1, "reqbufs: streaming active\n");
return -EBUSY;
}
/*
* Make sure all the required memory ops for given memory type
* are available.
*/
if (req->memory == V4L2_MEMORY_MMAP && __verify_mmap_ops(q)) {
dprintk(1, "reqbufs: MMAP for current setup unsupported\n");
return -EINVAL;
}
if (req->memory == V4L2_MEMORY_USERPTR && __verify_userptr_ops(q)) {
dprintk(1, "reqbufs: USERPTR for current setup unsupported\n");
return -EINVAL;
}
if (req->count == 0 || q->num_buffers != 0 || q->memory != req->memory) {
/*
* We already have buffers allocated, so first check if they
* are not in use and can be freed.
*/
if (q->memory == V4L2_MEMORY_MMAP && __buffers_in_use(q)) {
dprintk(1, "reqbufs: memory in use, cannot free\n");
return -EBUSY;
}
__vb2_queue_free(q);
/*
* In case of REQBUFS(0) return immediately without calling
* driver's queue_setup() callback and allocating resources.
*/
if (req->count == 0)
return 0;
}
/*
* Make sure the requested values and current defaults are sane.
*/
num_buffers = min_t(unsigned int, req->count, VIDEO_MAX_FRAME);
memset(plane_sizes, 0, sizeof(plane_sizes));
memset(q->alloc_ctx, 0, sizeof(q->alloc_ctx));
q->memory = req->memory;
/*
* Ask the driver how many buffers and planes per buffer it requires.
* Driver also sets the size and allocator context for each plane.
*/
ret = call_qop(q, queue_setup, q, &num_buffers, &num_planes,
plane_sizes, q->alloc_ctx);
if (ret)
return ret;
/* Finally, allocate buffers and video memory */
ret = __vb2_queue_alloc(q, req->memory, num_buffers, num_planes,
plane_sizes);
if (ret == 0) {
dprintk(1, "Memory allocation failed\n");
return -ENOMEM;
}
/*
* Check if driver can handle the allocated number of buffers.
*/
if (ret < num_buffers) {
unsigned int orig_num_buffers;
orig_num_buffers = num_buffers = ret;
ret = call_qop(q, queue_setup, q, &num_buffers, &num_planes,
plane_sizes, q->alloc_ctx);
if (ret)
goto free_mem;
if (orig_num_buffers < num_buffers) {
ret = -ENOMEM;
goto free_mem;
}
/*
* Ok, driver accepted smaller number of buffers.
*/
ret = num_buffers;
}
/*
* Return the number of successfully allocated buffers
* to the userspace.
*/
req->count = ret;
return 0;
free_mem:
__vb2_queue_free(q);
return ret;
}
/**
* __vb2_queue_alloc() - allocate videobuf buffer structures and (for MMAP type)
* video buffer memory for all buffers/planes on the queue and initializes the
* queue
*
* Returns the number of buffers successfully allocated.
*/
static int __vb2_queue_alloc(struct vb2_queue *q, enum v4l2_memory memory,
unsigned int num_buffers, unsigned int num_planes,
unsigned long plane_sizes[])
{
unsigned int buffer;
struct vb2_buffer *vb;
int ret;
for (buffer = 0; buffer < num_buffers; ++buffer) {
/* Allocate videobuf buffer structures */
vb = kzalloc(q->buf_struct_size, GFP_KERNEL);
if (!vb) {
dprintk(1, "Memory alloc for buffer struct failed\n");
break;
}
/* Length stores number of planes for multiplanar buffers */
if (V4L2_TYPE_IS_MULTIPLANAR(q->type))
vb->v4l2_buf.length = num_planes;
vb->state = VB2_BUF_STATE_DEQUEUED;
vb->vb2_queue = q;
vb->num_planes = num_planes;
vb->v4l2_buf.index = buffer;
vb->v4l2_buf.type = q->type;
vb->v4l2_buf.memory = memory;
/* Allocate video buffer memory for the MMAP type */
if (memory == V4L2_MEMORY_MMAP) {
ret = __vb2_buf_mem_alloc(vb, plane_sizes);
if (ret) {
dprintk(1, "Failed allocating memory for "
"buffer %d\n", buffer);
kfree(vb);
break;
}
/*
* Call the driver-provided buffer initialization
* callback, if given. An error in initialization
* results in queue setup failure.
*/
ret = call_qop(q, buf_init, vb);
if (ret) {
dprintk(1, "Buffer %d %p initialization"
" failed\n", buffer, vb);
__vb2_buf_mem_free(vb);
kfree(vb);
break;
}
}
q->bufs[buffer] = vb;
}
q->num_buffers = buffer;
__setup_offsets(q);
dprintk(1, "Allocated %d buffers, %d plane(s) each\n",
q->num_buffers, num_planes);
return buffer;
}
int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b)
{
struct vb2_buffer *vb;
int ret = 0;
if (q->fileio) {
dprintk(1, "qbuf: file io in progress\n");
return -EBUSY;
}
if (b->type != q->type) {
dprintk(1, "qbuf: invalid buffer type\n");
return -EINVAL;
}
if (b->index >= q->num_buffers) {
dprintk(1, "qbuf: buffer index out of range\n");
return -EINVAL;
}
vb = q->bufs[b->index];
if (NULL == vb) {
dprintk(1, "qbuf: buffer is NULL\n");
return -EINVAL;
}
if (b->memory != q->memory) {
dprintk(1, "qbuf: invalid memory type\n");
return -EINVAL;
}
if (vb->state != VB2_BUF_STATE_DEQUEUED) {
dprintk(1, "qbuf: buffer already in use\n");
return -EINVAL;
}
if (q->memory == V4L2_MEMORY_MMAP)
ret = __qbuf_mmap(vb, b);
else if (q->memory == V4L2_MEMORY_USERPTR)
ret = __qbuf_userptr(vb, b);
else {
WARN(1, "Invalid queue type\n");
return -EINVAL;
}
if (ret)
return ret;
ret = call_qop(q, buf_prepare, vb);
if (ret) {
dprintk(1, "qbuf: buffer preparation failed\n");
return ret;
}
list_add_tail(&vb->queued_entry, &q->queued_list);
vb->state = VB2_BUF_STATE_QUEUED;
if (q->streaming)
__enqueue_in_driver(vb);
dprintk(1, "qbuf of buffer %d succeeded\n", vb->v4l2_buf.index);
return 0;
}
static int __qbuf_userptr(struct vb2_buffer *vb, struct v4l2_buffer *b)
{
struct v4l2_plane planes[VIDEO_MAX_PLANES];
struct vb2_queue *q = vb->vb2_queue;
void *mem_priv;
unsigned int plane;
int ret;
int write = !V4L2_TYPE_IS_OUTPUT(q->type);
ret = __fill_vb2_buffer(vb, b, planes);
if (ret)
return ret;
for (plane = 0; plane < vb->num_planes; ++plane) {
if (vb->v4l2_planes[plane].m.userptr == planes[plane].m.userptr
&& vb->v4l2_planes[plane].length == planes[plane].length)
continue;
dprintk(3, "qbuf: userspace address for plane %d changed, "
"reacquiring memory\n", plane);
if (vb->planes[plane].mem_priv)
call_memop(q, plane, put_userptr,
vb->planes[plane].mem_priv);
vb->planes[plane].mem_priv = NULL;
if (q->mem_ops->get_userptr) {
mem_priv = q->mem_ops->get_userptr(q->alloc_ctx[plane],
planes[plane].m.userptr,
planes[plane].length,
write);
if (IS_ERR(mem_priv)) {
dprintk(1, "qbuf: failed acquiring userspace "
"memory for plane %d\n", plane);
ret = PTR_ERR(mem_priv);
goto err;
}
vb->planes[plane].mem_priv = mem_priv;
}
}
ret = call_qop(q, buf_init, vb);
if (ret) {
dprintk(1, "qbuf: buffer initialization failed\n");
goto err;
}
for (plane = 0; plane < vb->num_planes; ++plane)
vb->v4l2_planes[plane] = planes[plane];
return 0;
err:
for (plane = 0; plane < vb->num_planes; ++plane) {
if (vb->planes[plane].mem_priv)
call_memop(q, plane, put_userptr,
vb->planes[plane].mem_priv);
vb->planes[plane].mem_priv = NULL;
vb->v4l2_planes[plane].m.userptr = 0;
vb->v4l2_planes[plane].length = 0;
}
return ret;
}
int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
{
unsigned int num_buffers, num_planes;
unsigned long plane_sizes[VIDEO_MAX_PLANES];
int ret = 0;
num_buffers = 0;
num_planes = 0;
if (q->fileio) {
dprintk(1, "reqbufs: file io in progress\n");
return -EBUSY;
}
if (req->memory != V4L2_MEMORY_MMAP
&& req->memory != V4L2_MEMORY_USERPTR) {
dprintk(1, "reqbufs: unsupported memory type\n");
return -EINVAL;
}
if (req->type != q->type) {
dprintk(1, "reqbufs: requested type is incorrect\n");
return -EINVAL;
}
if (q->streaming) {
dprintk(1, "reqbufs: streaming active\n");
return -EBUSY;
}
if (req->memory == V4L2_MEMORY_MMAP && __verify_mmap_ops(q)) {
dprintk(1, "reqbufs: MMAP for current setup unsupported\n");
return -EINVAL;
}
if (req->memory == V4L2_MEMORY_USERPTR && __verify_userptr_ops(q)) {
dprintk(1, "reqbufs: USERPTR for current setup unsupported\n");
return -EINVAL;
}
if (q->memory == req->memory && req->count == q->num_buffers)
return 0;
if (req->count == 0 || q->num_buffers != 0 || q->memory != req->memory) {
if (q->memory == V4L2_MEMORY_MMAP && __buffers_in_use(q)) {
dprintk(1, "reqbufs: memory in use, cannot free\n");
return -EBUSY;
}
__vb2_queue_free(q);
if (req->count == 0)
return 0;
}
num_buffers = min_t(unsigned int, req->count, VIDEO_MAX_FRAME);
memset(plane_sizes, 0, sizeof(plane_sizes));
memset(q->alloc_ctx, 0, sizeof(q->alloc_ctx));
q->memory = req->memory;
ret = call_qop(q, queue_setup, q, NULL, &num_buffers,
&num_planes, q->plane_sizes, q->alloc_ctx);
if (ret)
return ret;
ret = __vb2_queue_alloc(q, req->memory, num_buffers, num_planes,
plane_sizes);
if (ret == 0) {
dprintk(1, "Memory allocation failed\n");
return -ENOMEM;
}
if (ret < num_buffers) {
unsigned int orig_num_buffers;
orig_num_buffers = num_buffers = ret;
ret = call_qop(q, queue_setup, q, NULL, &num_buffers,
&num_planes, q->plane_sizes, q->alloc_ctx);
if (ret)
goto free_mem;
if (orig_num_buffers < num_buffers) {
ret = -ENOMEM;
goto free_mem;
}
ret = num_buffers;
}
req->count = ret;
return 0;
free_mem:
__vb2_queue_free(q);
return ret;
}
