[PATCH v4,02/22] v4l2: handle restricted memory flags in queue setup

From: Yunfei Dong
Date: Mon Jan 29 2024 - 01:31:56 EST


From: Jeffrey Kardatzke <jkardatzke@xxxxxxxxxx>

Validates the restricted memory flags when setting up a queue and
ensures the queue has the proper capability.

Signed-off-by: Jeffrey Kardatzke <jkardatzke@xxxxxxxxxx>
Signed-off-by: Yunfei Dong <yunfei.dong@xxxxxxxxxxxx>
---
.../media/common/videobuf2/videobuf2-core.c | 21 +++++++++++++++++++
.../media/common/videobuf2/videobuf2-v4l2.c | 4 +++-
2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
index 41a832dd1426..7f5fd9ec9117 100644
--- a/drivers/media/common/videobuf2/videobuf2-core.c
+++ b/drivers/media/common/videobuf2/videobuf2-core.c
@@ -813,6 +813,15 @@ static bool verify_coherency_flags(struct vb2_queue *q, bool non_coherent_mem)
return true;
}

+static bool verify_restricted_mem_flags(struct vb2_queue *q, bool restricted_mem)
+{
+ if (restricted_mem != q->restricted_mem) {
+ dprintk(q, 1, "restricted memory model mismatch\n");
+ return false;
+ }
+ return true;
+}
+
int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
unsigned int flags, unsigned int *count)
{
@@ -820,6 +829,7 @@ 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;
+ bool restricted_mem = flags & V4L2_MEMORY_FLAG_RESTRICTED;
unsigned int i;
int ret = 0;

@@ -862,6 +872,9 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
return 0;
}

+ if (restricted_mem && (!q->allow_restricted_mem || memory != V4L2_MEMORY_DMABUF))
+ return -EINVAL;
+
/*
* Make sure the requested values and current defaults are sane.
*/
@@ -882,6 +895,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
if (ret)
return ret;
set_queue_coherency(q, non_coherent_mem);
+ q->restricted_mem = restricted_mem;

/*
* Ask the driver how many buffers and planes per buffer it requires.
@@ -986,6 +1000,7 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
unsigned plane_sizes[VB2_MAX_PLANES] = { };
bool non_coherent_mem = flags & V4L2_MEMORY_FLAG_NON_COHERENT;
unsigned int q_num_bufs = vb2_get_num_buffers(q);
+ bool restricted_mem = flags & V4L2_MEMORY_FLAG_RESTRICTED;
bool no_previous_buffers = !q_num_bufs;
int ret = 0;

@@ -994,6 +1009,9 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
return -ENOBUFS;
}

+ if (restricted_mem && (!q->allow_restricted_mem || memory != V4L2_MEMORY_DMABUF))
+ return -EINVAL;
+
if (no_previous_buffers) {
if (q->waiting_in_dqbuf && *count) {
dprintk(q, 1, "another dup()ped fd is waiting for a buffer\n");
@@ -1015,6 +1033,7 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
return ret;
q->waiting_for_buffers = !q->is_output;
set_queue_coherency(q, non_coherent_mem);
+ q->restricted_mem = restricted_mem;
} else {
if (q->memory != memory) {
dprintk(q, 1, "memory model mismatch\n");
@@ -1022,6 +1041,8 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
}
if (!verify_coherency_flags(q, non_coherent_mem))
return -EINVAL;
+ if (!verify_restricted_mem_flags(q, restricted_mem))
+ return -EINVAL;
}

num_buffers = min(*count, q->max_num_buffers - q_num_bufs);
diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
index 54d572c3b515..e825b1e2e22f 100644
--- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
+++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
@@ -686,6 +686,8 @@ 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;
+ if (q->allow_restricted_mem && q->io_modes & VB2_DMABUF)
+ *caps |= V4L2_BUF_CAP_SUPPORTS_RESTRICTED_MEM;
}

static void validate_memory_flags(struct vb2_queue *q,
@@ -700,7 +702,7 @@ static void validate_memory_flags(struct vb2_queue *q,
*flags = 0;
} else {
/* Clear all unknown flags. */
- *flags &= V4L2_MEMORY_FLAG_NON_COHERENT;
+ *flags &= V4L2_MEMORY_FLAG_NON_COHERENT | V4L2_MEMORY_FLAG_RESTRICTED;
}
}

--
2.18.0