[PATCH v15 51/56] media: core: Rework how create_buf index returned value is computed
Benjamin Gaignard
benjamin.gaignard at collabora.com
Thu Nov 9 08:35:07 PST 2023
When DELETE_BUFS will be introduced holes could created in bufs array.
To be able to reuse these unused indices reworking how create->index
is set is mandatory.
Let __vb2_queue_alloc() decide which first index is correct and
forward this to the caller.
Signed-off-by: Benjamin Gaignard <benjamin.gaignard at collabora.com>
---
.../media/common/videobuf2/videobuf2-core.c | 22 ++++++++++++-------
.../media/common/videobuf2/videobuf2-v4l2.c | 20 +++++++++++------
include/media/videobuf2-core.h | 5 ++++-
3 files changed, 31 insertions(+), 16 deletions(-)
diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
index 8c1df829745b..6379f8171405 100644
--- a/drivers/media/common/videobuf2/videobuf2-core.c
+++ b/drivers/media/common/videobuf2/videobuf2-core.c
@@ -447,11 +447,12 @@ static void vb2_queue_remove_buffer(struct vb2_buffer *vb)
*/
static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
unsigned int num_buffers, unsigned int num_planes,
- const unsigned plane_sizes[VB2_MAX_PLANES])
+ const unsigned int plane_sizes[VB2_MAX_PLANES],
+ unsigned int *first_index)
{
- unsigned int q_num_buffers = vb2_get_num_buffers(q);
unsigned int buffer, plane;
struct vb2_buffer *vb;
+ unsigned long index;
int ret;
/*
@@ -459,7 +460,11 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
* in the queue is below q->max_num_buffers
*/
num_buffers = min_t(unsigned int, num_buffers,
- q->max_num_buffers - q_num_buffers);
+ q->max_num_buffers - vb2_get_num_buffers(q));
+
+ index = vb2_get_num_buffers(q);
+
+ *first_index = index;
for (buffer = 0; buffer < num_buffers; ++buffer) {
/* Allocate vb2 buffer structures */
@@ -479,7 +484,7 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
vb->planes[plane].min_length = plane_sizes[plane];
}
- vb2_queue_add_buffer(q, vb, q_num_buffers + buffer);
+ vb2_queue_add_buffer(q, vb, index++);
call_void_bufop(q, init_buffer, vb);
/* Allocate video buffer memory for the MMAP type */
@@ -820,7 +825,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
unsigned int q_num_bufs = vb2_get_num_buffers(q);
unsigned plane_sizes[VB2_MAX_PLANES] = { };
bool non_coherent_mem = flags & V4L2_MEMORY_FLAG_NON_COHERENT;
- unsigned int i;
+ unsigned int i, first_index;
int ret = 0;
if (q->streaming) {
@@ -906,7 +911,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
/* Finally, allocate buffers and video memory */
allocated_buffers =
- __vb2_queue_alloc(q, memory, num_buffers, num_planes, plane_sizes);
+ __vb2_queue_alloc(q, memory, num_buffers, num_planes, plane_sizes, &first_index);
if (allocated_buffers == 0) {
dprintk(q, 1, "memory allocation failed\n");
ret = -ENOMEM;
@@ -980,7 +985,8 @@ EXPORT_SYMBOL_GPL(vb2_core_reqbufs);
int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
unsigned int flags, unsigned int *count,
unsigned int requested_planes,
- const unsigned int requested_sizes[])
+ const unsigned int requested_sizes[],
+ unsigned int *first_index)
{
unsigned int num_planes = 0, num_buffers, allocated_buffers;
unsigned plane_sizes[VB2_MAX_PLANES] = { };
@@ -1042,7 +1048,7 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
/* Finally, allocate buffers and video memory */
allocated_buffers = __vb2_queue_alloc(q, memory, num_buffers,
- num_planes, plane_sizes);
+ num_planes, plane_sizes, first_index);
if (allocated_buffers == 0) {
dprintk(q, 1, "memory allocation failed\n");
ret = -ENOMEM;
diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
index 440c3b1c18ec..d50ba1fb7f05 100644
--- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
+++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
@@ -799,11 +799,16 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create)
for (i = 0; i < requested_planes; i++)
if (requested_sizes[i] == 0)
return -EINVAL;
- return ret ? ret : vb2_core_create_bufs(q, create->memory,
- create->flags,
- &create->count,
- requested_planes,
- requested_sizes);
+ if (ret)
+ return ret;
+
+ ret = vb2_core_create_bufs(q, create->memory,
+ create->flags,
+ &create->count,
+ requested_planes,
+ requested_sizes,
+ &create->index);
+ return ret;
}
EXPORT_SYMBOL_GPL(vb2_create_bufs);
@@ -1031,15 +1036,16 @@ int vb2_ioctl_create_bufs(struct file *file, void *priv,
int res = vb2_verify_memory_type(vdev->queue, p->memory,
p->format.type);
- p->index = vdev->queue->num_buffers;
fill_buf_caps(vdev->queue, &p->capabilities);
validate_memory_flags(vdev->queue, p->memory, &p->flags);
/*
* 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.
*/
- if (p->count == 0)
+ if (p->count == 0) {
+ p->index = vb2_get_num_buffers(vdev->queue);
return res != -EBUSY ? res : 0;
+ }
if (res)
return res;
if (vb2_queue_is_busy(vdev->queue, file))
diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
index 5557d78b6f20..dbcdfcc4dc31 100644
--- a/include/media/videobuf2-core.h
+++ b/include/media/videobuf2-core.h
@@ -805,6 +805,8 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
* @count: requested buffer count.
* @requested_planes: number of planes requested.
* @requested_sizes: array with the size of the planes.
+ * @first_index: index of the first created buffer, all allocated buffers have
+ * indices in the range [first..first+count]
*
* Videobuf2 core helper to implement VIDIOC_CREATE_BUFS() operation. It is
* called internally by VB2 by an API-specific handler, like
@@ -821,7 +823,8 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
unsigned int flags, unsigned int *count,
unsigned int requested_planes,
- const unsigned int requested_sizes[]);
+ const unsigned int requested_sizes[],
+ unsigned int *first_index);
/**
* vb2_core_prepare_buf() - Pass ownership of a buffer from userspace
--
2.39.2
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