[PATCH v7 02/28] v4l2: handle restricted memory flags in queue setup

[Yunfei Dong <yunfei.dong@mediatek.com>]

From: Jeffrey Kardatzke <jkardatzke@google.com>

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

Signed-off-by: Jeffrey Kardatzke <jkardatzke@google.com>
Signed-off-by: Yunfei Dong <yunfei.dong@mediatek.com>
[Yunfei: Change reviewer's comments]
---
 .../media/common/videobuf2/videobuf2-core.c   | 29 +++++++++++++++++++
 .../media/common/videobuf2/videobuf2-v4l2.c   |  4 ++-
 2 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
index 0217392fcc0d..44080121f37e 100644
--- a/drivers/media/common/videobuf2/videobuf2-core.c
+++ b/drivers/media/common/videobuf2/videobuf2-core.c
@@ -830,6 +830,23 @@ 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;
+}
+
+static inline int restricted_mem_mismatch(bool restricted_mem, struct vb2_queue *q,
+					  enum vb2_memory memory)
+{
+	return restricted_mem && (!q->allow_restricted_mem || memory != VB2_MEMORY_DMABUF) ?
+	       -1 : 0;
+}
+
 static int vb2_core_allocated_buffers_storage(struct vb2_queue *q)
 {
 	if (!q->bufs)
@@ -863,6 +880,7 @@ 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, first_index;
 	int ret = 0;
 
@@ -906,6 +924,9 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
 			return 0;
 	}
 
+	if (restricted_mem_mismatch(restricted_mem, q, memory))
+		return -EINVAL;
+
 	/*
 	 * Make sure the requested values and current defaults are sane.
 	 */
@@ -923,6 +944,7 @@ 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.
@@ -1031,6 +1053,7 @@ 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;
 
@@ -1039,6 +1062,9 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
 		return -ENOBUFS;
 	}
 
+	if (restricted_mem_mismatch(restricted_mem, q, memory))
+		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");
@@ -1057,6 +1083,7 @@ 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");
@@ -1064,6 +1091,8 @@ 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 293f3d5f1c4e..9ee24e537e0c 100644
--- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
+++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
@@ -682,7 +682,7 @@ static void vb2_set_flags_and_caps(struct vb2_queue *q, u32 memory,
 		*flags = 0;
 	} else {
 		/* Clear all unknown flags. */
-		*flags &= V4L2_MEMORY_FLAG_NON_COHERENT;
+		*flags &= V4L2_MEMORY_FLAG_NON_COHERENT | V4L2_MEMORY_FLAG_RESTRICTED;
 	}
 
 	*caps |= V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS;
@@ -698,6 +698,8 @@ static void vb2_set_flags_and_caps(struct vb2_queue *q, u32 memory,
 		*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;
 	if (max_num_bufs) {
 		*max_num_bufs = q->max_num_buffers;
 		*caps |= V4L2_BUF_CAP_SUPPORTS_MAX_NUM_BUFFERS;
-- 
2.18.0