Several functions implementing VIDIOC_REQBUFS and _CREATE_BUFS all use almost
the same code to fill in the flags and capability fields. Refactor this into a
new vb2_set_flags_and_caps() function that replaces the old fill_buf_caps()
and validate_memory_flags() functions.
This also fixes a bug where vb2_ioctl_create_bufs() would not set the
V4L2_BUF_CAP_SUPPORTS_MAX_NUM_BUFFERS cap and also not fill in the
max_num_buffers field.
Fixes: d055a76c0065 ("media: core: Report the maximum possible number of buffers for the queue")
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Reviewed-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxxxxx>
---
Changes since v2: rebased on top of:
https://patchwork.linuxtv.org/project/linux-media/patch/20240118121452.29151-1-benjamin.gaignard@xxxxxxxxxxxxx/
Tomasz, I didn't make any other changes since I want to keep the behavior
the same as before (except for fixing the missing cap issue).
There is certainly room for improvement, but that's not something for a
fixes patch.
---
.../media/common/videobuf2/videobuf2-v4l2.c | 53 +++++++++----------
1 file changed, 25 insertions(+), 28 deletions(-)
diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
index 6380155d8575..c575198e8354 100644
--- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
+++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
@@ -671,8 +671,20 @@ int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b)
}
EXPORT_SYMBOL(vb2_querybuf);
-static void fill_buf_caps(struct vb2_queue *q, u32 *caps)
+static void vb2_set_flags_and_caps(struct vb2_queue *q, u32 memory,
+ u32 *flags, u32 *caps, u32 *max_num_bufs)
{
+ if (!q->allow_cache_hints || memory != V4L2_MEMORY_MMAP) {
+ /*
+ * This needs to clear V4L2_MEMORY_FLAG_NON_COHERENT only,
+ * but in order to avoid bugs we zero out all bits.
+ */
+ *flags = 0;
+ } else {
+ /* Clear all unknown flags. */
+ *flags &= V4L2_MEMORY_FLAG_NON_COHERENT;
+ }
+
*caps = V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS;
if (q->io_modes & VB2_MMAP)
*caps |= V4L2_BUF_CAP_SUPPORTS_MMAP;
@@ -686,21 +698,9 @@ static void fill_buf_caps(struct vb2_queue *q, u32 *caps)
*caps |= V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS;
if (q->supports_requests)
*caps |= V4L2_BUF_CAP_SUPPORTS_REQUESTS;
-}
-
-static void validate_memory_flags(struct vb2_queue *q,
- int memory,
- u32 *flags)
-{
- if (!q->allow_cache_hints || memory != V4L2_MEMORY_MMAP) {
- /*
- * This needs to clear V4L2_MEMORY_FLAG_NON_COHERENT only,
- * but in order to avoid bugs we zero out all bits.
- */
- *flags = 0;
- } else {
- /* Clear all unknown flags. */
- *flags &= V4L2_MEMORY_FLAG_NON_COHERENT;
+ if (max_num_bufs) {
+ *max_num_bufs = q->max_num_buffers;
+ *caps |= V4L2_BUF_CAP_SUPPORTS_MAX_NUM_BUFFERS;
}
}
@@ -709,8 +709,8 @@ int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
int ret = vb2_verify_memory_type(q, req->memory, req->type);
u32 flags = req->flags;
- fill_buf_caps(q, &req->capabilities);
- validate_memory_flags(q, req->memory, &flags);
+ vb2_set_flags_and_caps(q, req->memory, &flags,
+ &req->capabilities, NULL);
req->flags = flags;
return ret ? ret : vb2_core_reqbufs(q, req->memory,
req->flags, &req->count);
@@ -751,11 +751,9 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create)
int ret = vb2_verify_memory_type(q, create->memory, f->type);
unsigned i;
- fill_buf_caps(q, &create->capabilities);
- validate_memory_flags(q, create->memory, &create->flags);
create->index = vb2_get_num_buffers(q);
- create->max_num_buffers = q->max_num_buffers;
- create->capabilities |= V4L2_BUF_CAP_SUPPORTS_MAX_NUM_BUFFERS;
+ vb2_set_flags_and_caps(q, create->memory, &create->flags,
+ &create->capabilities, &create->max_num_buffers);
if (create->count == 0)
return ret != -EBUSY ? ret : 0;
@@ -1006,8 +1004,8 @@ int vb2_ioctl_reqbufs(struct file *file, void *priv,
int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type);
u32 flags = p->flags;
- fill_buf_caps(vdev->queue, &p->capabilities);
- validate_memory_flags(vdev->queue, p->memory, &flags);
+ vb2_set_flags_and_caps(vdev->queue, p->memory, &flags,
+ &p->capabilities, NULL);
p->flags = flags;
if (res)
return res;
@@ -1026,12 +1024,11 @@ int vb2_ioctl_create_bufs(struct file *file, void *priv,
struct v4l2_create_buffers *p)
{
struct video_device *vdev = video_devdata(file);
- int res = vb2_verify_memory_type(vdev->queue, p->memory,
- p->format.type);
+ int res = vb2_verify_memory_type(vdev->queue, p->memory, p->format.type);
p->index = vb2_get_num_buffers(vdev->queue);
- fill_buf_caps(vdev->queue, &p->capabilities);
- validate_memory_flags(vdev->queue, p->memory, &p->flags);
+ vb2_set_flags_and_caps(vdev->queue, p->memory, &p->flags,
+ &p->capabilities, &p->max_num_buffers);
/*
* If count == 0, then just check if memory and type are valid.
* Any -EBUSY result from vb2_verify_memory_type can be mapped to 0.
--
2.42.0
