The two operations are very similar, refactor most of the code in a
helper function.
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
drivers/media/v4l2-core/videobuf2-core.c | 202 ++++++++++++-------------------
1 file changed, 79 insertions(+), 123 deletions(-)
diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c
index 7c2a8ce..c9f8c3f 100644
--- a/drivers/media/v4l2-core/videobuf2-core.c
+++ b/drivers/media/v4l2-core/videobuf2-core.c
@@ -1231,42 +1231,31 @@ static int __buf_prepare(struct vb2_buffer *vb, const struct v4l2_buffer *b)
return ret;
}
-/**
- * vb2_prepare_buf() - Pass ownership of a buffer from userspace to the kernel
- * @q: videobuf2 queue
- * @b: buffer structure passed from userspace to vidioc_prepare_buf
- * handler in driver
- *
- * Should be called from vidioc_prepare_buf 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,
- *
- * The return values from this function are intended to be directly returned
- * from vidioc_prepare_buf handler in driver.
- */
-int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b)
+static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b,
+ const char *opname,
+ int (*handler)(struct vb2_queue *,
+ struct v4l2_buffer *,
+ struct vb2_buffer *))
{
struct rw_semaphore *mmap_sem = NULL;
struct vb2_buffer *vb;
int ret;
/*
- * In case of user pointer buffers vb2 allocator needs to get direct
- * access to userspace pages. This requires getting read access on
- * mmap semaphore in the current process structure. The same
- * semaphore is taken before calling mmap operation, while both mmap
- * and prepare_buf are called by the driver or v4l2 core with driver's
- * lock held. To avoid a AB-BA deadlock (mmap_sem then driver's lock in
- * mmap and driver's lock then mmap_sem in prepare_buf) the videobuf2
- * core release driver's lock, takes mmap_sem and then takes again
- * driver's lock.
+ * In case of user pointer buffers vb2 allocators need to get direct
+ * access to userspace pages. This requires getting the mmap semaphore
+ * for read access in the current process structure. The same semaphore
+ * is taken before calling mmap operation, while both qbuf/prepare_buf
+ * and mmap are called by the driver or v4l2 core with the driver's lock
+ * held. To avoid an AB-BA deadlock (mmap_sem then driver's lock in mmap
+ * and driver's lock then mmap_sem in qbuf/prepare_buf) the videobuf2
+ * core releases the driver's lock, takes mmap_sem and then takes the
+ * driver's lock again.
*
- * To avoid race with other vb2 calls, which might be called after
- * releasing driver's lock, this operation is performed at the
- * beggining of prepare_buf processing. This way the queue status is
- * consistent after getting driver's lock back.
+ * To avoid racing with other vb2 calls, which might be called after
+ * releasing the driver's lock, this operation is performed at the
+ * beginning of qbuf/prepare_buf processing. This way the queue status
+ * is consistent after getting the driver's lock back.
*/
if (q->memory == V4L2_MEMORY_USERPTR) {
mmap_sem = ¤t->mm->mmap_sem;
@@ -1276,19 +1265,19 @@ int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b)
}
if (q->fileio) {
- dprintk(1, "%s(): file io in progress\n", __func__);
+ dprintk(1, "%s(): file io in progress\n", opname);
ret = -EBUSY;
goto unlock;
}
if (b->type != q->type) {
- dprintk(1, "%s(): invalid buffer type\n", __func__);
+ dprintk(1, "%s(): invalid buffer type\n", opname);
ret = -EINVAL;
goto unlock;
}
if (b->index >= q->num_buffers) {
- dprintk(1, "%s(): buffer index out of range\n", __func__);
+ dprintk(1, "%s(): buffer index out of range\n", opname);
ret = -EINVAL;
goto unlock;
}
@@ -1296,131 +1285,83 @@ int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b)
vb = q->bufs[b->index];
if (NULL == vb) {
/* Should never happen */
- dprintk(1, "%s(): buffer is NULL\n", __func__);
+ dprintk(1, "%s(): buffer is NULL\n", opname);
ret = -EINVAL;
goto unlock;
}
if (b->memory != q->memory) {
- dprintk(1, "%s(): invalid memory type\n", __func__);
+ dprintk(1, "%s(): invalid memory type\n", opname);
ret = -EINVAL;
goto unlock;
}
- if (vb->state != VB2_BUF_STATE_DEQUEUED) {
- dprintk(1, "%s(): invalid buffer state %d\n", __func__, vb->state);
- ret = -EINVAL;
- goto unlock;
- }
ret = __verify_planes_array(vb, b);
- if (ret < 0)
+ if (ret)
goto unlock;
- ret = __buf_prepare(vb, b);
- if (ret < 0)
+ ret = handler(q, b, vb);
+ if (ret)
goto unlock;
+ /* Fill buffer information for the userspace */
__fill_v4l2_buffer(vb, b);
+ dprintk(1, "%s() of buffer %d succeeded\n", opname, vb->v4l2_buf.index);
unlock:
if (mmap_sem)
up_read(mmap_sem);
return ret;
}
-EXPORT_SYMBOL_GPL(vb2_prepare_buf);
+
+static int __vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b,
+ struct vb2_buffer *vb)
+{
+ if (vb->state != VB2_BUF_STATE_DEQUEUED) {
+ dprintk(1, "%s(): invalid buffer state %d\n", __func__,
+ vb->state);
+ return -EINVAL;
+ }
+
+ return __buf_prepare(vb, b);
+}
/**
- * vb2_qbuf() - Queue a buffer from userspace
+ * vb2_prepare_buf() - Pass ownership of a buffer from userspace to the kernel
* @q: videobuf2 queue
- * @b: buffer structure passed from userspace to vidioc_qbuf handler
- * in driver
+ * @b: buffer structure passed from userspace to vidioc_prepare_buf
+ * handler in driver
*
- * Should be called from vidioc_qbuf ioctl handler of a driver.
+ * Should be called from vidioc_prepare_buf ioctl handler of a driver.
* This function:
* 1) verifies the passed buffer,
- * 2) if necessary, 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.
+ * 2) calls buf_prepare callback in the driver (if provided), in which
+ * driver-specific buffer initialization can be performed,
*
* The return values from this function are intended to be directly returned
- * from vidioc_qbuf handler in driver.
+ * from vidioc_prepare_buf handler in driver.
*/
-int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b)
+int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b)
{
- struct rw_semaphore *mmap_sem = NULL;
- struct vb2_buffer *vb;
- int ret = 0;
-
- /*
- * In case of user pointer buffers vb2 allocator needs to get direct
- * access to userspace pages. This requires getting read access on
- * mmap semaphore in the current process structure. The same
- * semaphore is taken before calling mmap operation, while both mmap
- * and qbuf are called by the driver or v4l2 core with driver's lock
- * held. To avoid a AB-BA deadlock (mmap_sem then driver's lock in
- * mmap and driver's lock then mmap_sem in qbuf) the videobuf2 core
- * release driver's lock, takes mmap_sem and then takes again driver's
- * lock.
- *
- * To avoid race with other vb2 calls, which might be called after
- * releasing driver's lock, this operation is performed at the
- * beggining of qbuf processing. This way the queue status is
- * consistent after getting driver's lock back.
- */
- if (q->memory == V4L2_MEMORY_USERPTR) {
- mmap_sem = ¤t->mm->mmap_sem;
- call_qop(q, wait_prepare, q);
- down_read(mmap_sem);
- call_qop(q, wait_finish, q);
- }
-
- if (q->fileio) {
- dprintk(1, "qbuf: file io in progress\n");
- ret = -EBUSY;
- goto unlock;
- }
-
- if (b->type != q->type) {
- dprintk(1, "qbuf: invalid buffer type\n");
- ret = -EINVAL;
- goto unlock;
- }
-
- if (b->index >= q->num_buffers) {
- dprintk(1, "qbuf: buffer index out of range\n");
- ret = -EINVAL;
- goto unlock;
- }
-
- vb = q->bufs[b->index];
- if (NULL == vb) {
- /* Should never happen */
- dprintk(1, "qbuf: buffer is NULL\n");
- ret = -EINVAL;
- goto unlock;
- }
+ return vb2_queue_or_prepare_buf(q, b, "prepare_buf", __vb2_prepare_buf);
+}
+EXPORT_SYMBOL_GPL(vb2_prepare_buf);
- if (b->memory != q->memory) {
- dprintk(1, "qbuf: invalid memory type\n");
- ret = -EINVAL;
- goto unlock;
- }
- ret = __verify_planes_array(vb, b);
- if (ret)
- goto unlock;
+static int __vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b,
+ struct vb2_buffer *vb)
+{
+ int ret;
switch (vb->state) {
case VB2_BUF_STATE_DEQUEUED:
ret = __buf_prepare(vb, b);
if (ret)
- goto unlock;
+ return ret;
case VB2_BUF_STATE_PREPARED:
break;
default:
dprintk(1, "qbuf: buffer already in use\n");
- ret = -EINVAL;
- goto unlock;
+ return -EINVAL;
}
/*
@@ -1437,14 +1378,29 @@ int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b)
if (q->streaming)
__enqueue_in_driver(vb);
- /* Fill buffer information for the userspace */
- __fill_v4l2_buffer(vb, b);
+ return 0;
+}
- dprintk(1, "qbuf of buffer %d succeeded\n", vb->v4l2_buf.index);
-unlock:
- if (mmap_sem)
- up_read(mmap_sem);
- return ret;
+/**
+ * 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) if necessary, 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)
+{
+ return vb2_queue_or_prepare_buf(q, b, "qbuf", __vb2_qbuf);
}
EXPORT_SYMBOL_GPL(vb2_qbuf);
--
1.8.1.5
--
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