media: videobuf2: add queue memory coherency parameter

Preparations for future V4L2_MEMORY_FLAG_NON_COHERENT support. Extend the vb2_core_reqbufs() parameters list to accept requests' ->flags, which will be used for memory coherency configuration. An attempt to allocate a buffer with coherency requirements that do not match the queue's consistency model will fail.

Sergey Senozhatsky committed 5 years ago

Commit b00a9e51 parent 965c1e04 files · +43 −11Browse files

Unified · Split

4 files

drivers/media/common/videobuf2/videobuf2-core.c +31 −6
drivers/media/common/videobuf2/videobuf2-v4l2.c +3 −2
drivers/media/dvb-core/dvb_vb2.c +1 −1
include/media/videobuf2-core.h +8 −2

drivers/media/common/videobuf2/videobuf2-core.c+31−6

 }
 EXPORT_SYMBOL(vb2_verify_memory_type);
+static void set_queue_coherency(struct vb2_queue *q, bool non_coherent_mem)
+{
+	q->non_coherent_mem = 0;
+	if (!vb2_queue_allows_cache_hints(q))
+		return;
+	q->non_coherent_mem = non_coherent_mem;
+}
+static bool verify_coherency_flags(struct vb2_queue *q, bool non_coherent_mem)
+{
+	if (non_coherent_mem != q->non_coherent_mem) {
+		dprintk(q, 1, "memory coherency model mismatch\n");
+		return false;
+	}
+	return true;
+}
 int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
-		     unsigned int *count)
+		     unsigned int flags, unsigned int *count)
 {
 	unsigned int num_buffers, allocated_buffers, num_planes = 0;
 	unsigned plane_sizes[VB2_MAX_PLANES] = { };
+	bool non_coherent_mem = false;
 	unsigned int i;
 	int ret;
 	}
 	if (*count == 0 || q->num_buffers != 0 ||
-	    (q->memory != VB2_MEMORY_UNKNOWN && q->memory != memory)) {
+	    (q->memory != VB2_MEMORY_UNKNOWN && q->memory != memory) ||
+	    !verify_coherency_flags(q, non_coherent_mem)) {
 		/*
 		 * We already have buffers allocated, so first check if they
 		 * are not in use and can be freed.
 	num_buffers = min_t(unsigned int, num_buffers, VB2_MAX_FRAME);
 	memset(q->alloc_devs, 0, sizeof(q->alloc_devs));
 	q->memory = memory;
+	set_queue_coherency(q, non_coherent_mem);
 	/*
 	 * Ask the driver how many buffers and planes per buffer it requires.
 EXPORT_SYMBOL_GPL(vb2_core_reqbufs);
 int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
-			 unsigned int *count,
+			 unsigned int flags, unsigned int *count,
 			 unsigned int requested_planes,
 			 const unsigned int requested_sizes[])
 {
 	unsigned int num_planes = 0, num_buffers, allocated_buffers;
 	unsigned plane_sizes[VB2_MAX_PLANES] = { };
+	bool non_coherent_mem = false;
 	int ret;
 	if (q->num_buffers == VB2_MAX_FRAME) {
 		memset(q->alloc_devs, 0, sizeof(q->alloc_devs));
 		q->memory = memory;
 		q->waiting_for_buffers = !q->is_output;
+		set_queue_coherency(q, non_coherent_mem);
 	} else {
 		if (q->memory != memory) {
 			dprintk(q, 1, "memory model mismatch\n");
 			return -EINVAL;
 		}
+		if (!verify_coherency_flags(q, non_coherent_mem))
+			return -EINVAL;
 	}
 	num_buffers = min(*count, VB2_MAX_FRAME - q->num_buffers);
 	fileio->memory = VB2_MEMORY_MMAP;
 	fileio->type = q->type;
 	q->fileio = fileio;
-	ret = vb2_core_reqbufs(q, fileio->memory, &fileio->count);
+	ret = vb2_core_reqbufs(q, fileio->memory, 0, &fileio->count);
 	if (ret)
 		goto err_kfree;
 err_reqbufs:
 	fileio->count = 0;
-	vb2_core_reqbufs(q, fileio->memory, &fileio->count);
+	vb2_core_reqbufs(q, fileio->memory, 0, &fileio->count);
 err_kfree:
 	q->fileio = NULL;
 		vb2_core_streamoff(q, q->type);
 		q->fileio = NULL;
 		fileio->count = 0;
-		vb2_core_reqbufs(q, fileio->memory, &fileio->count);
+		vb2_core_reqbufs(q, fileio->memory, 0, &fileio->count);
 		kfree(fileio);
 		dprintk(q, 3, "file io emulator closed\n");
 	}

drivers/media/common/videobuf2/videobuf2-v4l2.c+3−2

 	int ret = vb2_verify_memory_type(q, req->memory, req->type);
 	fill_buf_caps(q, &req->capabilities);
-	return ret ? ret : vb2_core_reqbufs(q, req->memory, &req->count);
+	return ret ? ret : vb2_core_reqbufs(q, req->memory, 0, &req->count);
 }
 EXPORT_SYMBOL_GPL(vb2_reqbufs);
 		if (requested_sizes[i] == 0)
 			return -EINVAL;
 	return ret ? ret : vb2_core_create_bufs(q, create->memory,
+						0,
 						&create->count,
 						requested_planes,
 						requested_sizes);
 		return res;
 	if (vb2_queue_is_busy(vdev, file))
 		return -EBUSY;
-	res = vb2_core_reqbufs(vdev->queue, p->memory, &p->count);
+	res = vb2_core_reqbufs(vdev->queue, p->memory, 0, &p->count);
 	/* If count == 0, then the owner has released all buffers and he
 	   is no longer owner of the queue. Otherwise we have a new owner. */
 	if (res == 0)

drivers/media/dvb-core/dvb_vb2.c+1−1

@@ -342,7 +342,7 @@ int dvb_vb2_reqbufs(struct dvb_vb2_ctx ctx, struct dmx_requestbuffers req) · 341 unmodified lines
342		342
343	ctx->buf_siz = req->size;	343	ctx->buf_siz = req->size;
344	ctx->buf_cnt = req->count;	344	ctx->buf_cnt = req->count;
345	ret = vb2_core_reqbufs(&ctx->vb_q, VB2_MEMORY_MMAP, &req->count);	345	ret = vb2_core_reqbufs(&ctx->vb_q, VB2_MEMORY_MMAP, 0, &req->count);
346	if (ret) {	346	if (ret) {
347	ctx->state = DVB_VB2_STATE_NONE;	347	ctx->state = DVB_VB2_STATE_NONE;
348	dprintk(1, "[%s] count=%d size=%d errno=%d\n", ctx->name,	348	dprintk(1, "[%s] count=%d size=%d errno=%d\n", ctx->name,

include/media/videobuf2-core.h+8−2

  * @allow_cache_hints: when set user-space can pass cache management hints in
  *		order to skip cache flush/invalidation on ->prepare() or/and
  *		->finish().
+ * @non_coherent_mem: when set queue will attempt to allocate buffers using
+ *		non-coherent memory.
  * @lock:	pointer to a mutex that protects the &struct vb2_queue. The
  *		driver can set this to a mutex to let the v4l2 core serialize
  *		the queuing ioctls. If the driver wants to handle locking
 	unsigned int			uses_qbuf:1;
 	unsigned int			uses_requests:1;
 	unsigned int			allow_cache_hints:1;
+	unsigned int			non_coherent_mem:1;
 	struct mutex			*lock;
 	void				*owner;
  * vb2_core_reqbufs() - Initiate streaming.
  * @q:		pointer to &struct vb2_queue with videobuf2 queue.
  * @memory:	memory type, as defined by &enum vb2_memory.
+ * @flags:	auxiliary queue/buffer management flags. Currently, the only
+ *		used flag is %V4L2_MEMORY_FLAG_NON_COHERENT.
  * @count:	requested buffer count.
  *
  * Videobuf2 core helper to implement VIDIOC_REQBUF() operation. It is called
  * Return: returns zero on success; an error code otherwise.
  */
 int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
-		    unsigned int *count);
+		     unsigned int flags, unsigned int *count);
 /**
  * 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.
+ * @flags: auxiliary queue/buffer management flags.
  * @count: requested buffer count.
  * @requested_planes: number of planes requested.
  * @requested_sizes: array with the size of the planes.
  * 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 flags, unsigned int *count,
 			 unsigned int requested_planes,
 			 const unsigned int requested_sizes[]);