[RFC][PATCH 06/15] videobuf2: handle V4L2_FLAG_MEMORY_NON_CONSISTENT in CREATE_BUFS
From: Sergey Senozhatsky
Date: Mon Dec 16 2019 - 22:21:08 EST
This patch lets user-space to request a non-consistent memory
allocation during CREATE_BUFS ioctl call. struct v4l2_create_buffers
has seven 4-byte reserved areas, so reserved[0] is renamed to ->flags.
The struct, thus, now has six reserved 4-byte regions.
Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
---
.../media/uapi/v4l/vidioc-create-bufs.rst | 8 +++++-
.../media/common/videobuf2/videobuf2-core.c | 27 +++++++++++++++----
.../media/common/videobuf2/videobuf2-v4l2.c | 7 ++++-
drivers/media/v4l2-core/v4l2-ioctl.c | 2 +-
include/media/videobuf2-core.h | 4 ++-
include/uapi/linux/videodev2.h | 3 ++-
6 files changed, 41 insertions(+), 10 deletions(-)
diff --git a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst
index bd08e4f77ae4..c56e80659b4a 100644
--- a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst
+++ b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst
@@ -121,7 +121,13 @@ than the number requested.
other changes, then set ``count`` to 0, ``memory`` to
``V4L2_MEMORY_MMAP`` and ``format.type`` to the buffer type.
* - __u32
- - ``reserved``\ [7]
+ - ``flags``
+ - Specifies additional buffer management attributes. E.g. when
+ ``V4L2_FLAG_MEMORY_NON_CONSISTENT`` set vb2 backends may be allocated
+ in non-consistent memory.
+
+ * - __u32
+ - ``reserved``\ [6]
- A place holder for future extensions. Drivers and applications
must set the array to zero.
diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
index 668c56df13f6..d1012a24755d 100644
--- a/drivers/media/common/videobuf2/videobuf2-core.c
+++ b/drivers/media/common/videobuf2/videobuf2-core.c
@@ -812,9 +812,21 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
}
EXPORT_SYMBOL_GPL(vb2_core_reqbufs);
+static bool verify_consistency_attr(struct vb2_queue *q, bool consistent_mem)
+{
+ bool queue_attr = q->dma_attrs & DMA_ATTR_NON_CONSISTENT;
+
+ if (consistent_mem != queue_attr) {
+ dprintk(1, "memory consistency model mismatch\n");
+ return false;
+ }
+ return true;
+}
+
int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
- unsigned int *count, unsigned requested_planes,
- const unsigned requested_sizes[])
+ bool consistent_mem, unsigned int *count,
+ unsigned requested_planes,
+ const unsigned requested_sizes[])
{
unsigned int num_planes = 0, num_buffers, allocated_buffers;
unsigned plane_sizes[VB2_MAX_PLANES] = { };
@@ -832,10 +844,15 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
}
memset(q->alloc_devs, 0, sizeof(q->alloc_devs));
q->memory = memory;
+ __set_queue_consistency(q, consistent_mem);
q->waiting_for_buffers = !q->is_output;
- } else if (q->memory != memory) {
- dprintk(1, "memory model mismatch\n");
- return -EINVAL;
+ } else {
+ if (q->memory != memory) {
+ dprintk(1, "memory model mismatch\n");
+ return -EINVAL;
+ }
+ if (!verify_consistency_attr(q, consistent_mem))
+ return -EINVAL;
}
num_buffers = min(*count, VB2_MAX_FRAME - q->num_buffers);
diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
index 0eabb589684f..48d123a1ac2a 100644
--- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
+++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
@@ -730,6 +730,7 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create)
unsigned requested_sizes[VIDEO_MAX_PLANES];
struct v4l2_format *f = &create->format;
int ret = vb2_verify_memory_type(q, create->memory, f->type);
+ bool consistent = true;
unsigned i;
fill_buf_caps(q, &create->capabilities);
@@ -775,7 +776,11 @@ 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,
+
+ if (create->flags & V4L2_FLAG_MEMORY_NON_CONSISTENT)
+ consistent = false;
+
+ return ret ? ret : vb2_core_create_bufs(q, create->memory, consistent,
&create->count, requested_planes, requested_sizes);
}
EXPORT_SYMBOL_GPL(vb2_create_bufs);
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 225d06819bce..793cb6534de4 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -2012,7 +2012,7 @@ static int v4l_create_bufs(const struct v4l2_ioctl_ops *ops,
if (ret)
return ret;
- CLEAR_AFTER_FIELD(create, capabilities);
+ CLEAR_AFTER_FIELD(create, flags);
v4l_sanitize_format(&create->format);
diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
index 810af5cf5742..5e5450bdabbd 100644
--- a/include/media/videobuf2-core.h
+++ b/include/media/videobuf2-core.h
@@ -757,6 +757,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
* vb2_core_create_bufs() - Allocate buffers and any required auxiliary structs
* @q: pointer to &struct vb2_queue with videobuf2 queue.
* @memory: memory type, as defined by &enum vb2_memory.
+ * @consistent_mem: memory consistency model.
* @count: requested buffer count.
* @requested_planes: number of planes requested.
* @requested_sizes: array with the size of the planes.
@@ -774,7 +775,8 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
* Return: returns zero on success; an error code otherwise.
*/
int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
- unsigned int *count, unsigned int requested_planes,
+ bool consistent_mem, unsigned int *count,
+ unsigned int requested_planes,
const unsigned int requested_sizes[]);
/**
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 73a4854f71bd..82e2ded5a136 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -2419,7 +2419,8 @@ struct v4l2_create_buffers {
__u32 memory;
struct v4l2_format format;
__u32 capabilities;
- __u32 reserved[7];
+ __u32 flags;
+ __u32 reserved[6];
};
/*
--
2.24.1.735.g03f4e72817-goog