Tested on bcm2710 (Raspberry Pi 3B). Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
		
			
				
	
	
		
			84 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
			
		
		
	
	
			84 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
From 74ac8bd3b5c6ed23308341fa41681db6a3b45c46 Mon Sep 17 00:00:00 2001
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From: Dave Stevenson <dave.stevenson@raspberrypi.org>
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Date: Mon, 29 Oct 2018 17:57:45 +0000
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Subject: [PATCH] media: videobuf2: Allow exporting of a struct dmabuf
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videobuf2 only allowed exporting a dmabuf as a file descriptor,
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but there are instances where having the struct dma_buf is
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useful within the kernel.
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Split the current implementation into two, one step which
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exports a struct dma_buf, and the second which converts that
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into an fd.
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Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
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---
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 .../media/common/videobuf2/videobuf2-core.c   | 21 ++++++++++++++++---
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 include/media/videobuf2-core.h                | 15 +++++++++++++
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 2 files changed, 33 insertions(+), 3 deletions(-)
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--- a/drivers/media/common/videobuf2/videobuf2-core.c
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+++ b/drivers/media/common/videobuf2/videobuf2-core.c
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@@ -2073,12 +2073,12 @@ static int __find_plane_by_offset(struct
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 	return -EINVAL;
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 }
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-int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type,
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-		unsigned int index, unsigned int plane, unsigned int flags)
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+int vb2_core_expbuf_dmabuf(struct vb2_queue *q, unsigned int type,
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+			   unsigned int index, unsigned int plane,
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+			   unsigned int flags, struct dma_buf **dmabuf)
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 {
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 	struct vb2_buffer *vb = NULL;
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 	struct vb2_plane *vb_plane;
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-	int ret;
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 	struct dma_buf *dbuf;
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 	if (q->memory != VB2_MEMORY_MMAP) {
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@@ -2128,6 +2128,21 @@ int vb2_core_expbuf(struct vb2_queue *q,
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 		return -EINVAL;
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 	}
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+	*dmabuf = dbuf;
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+	return 0;
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+}
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+EXPORT_SYMBOL_GPL(vb2_core_expbuf_dmabuf);
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+
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+int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type,
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+		    unsigned int index, unsigned int plane, unsigned int flags)
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+{
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+	struct dma_buf *dbuf;
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+	int ret;
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+
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+	ret = vb2_core_expbuf_dmabuf(q, type, index, plane, flags, &dbuf);
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+	if (ret)
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+		return ret;
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+
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 	ret = dma_buf_fd(dbuf, flags & ~O_ACCMODE);
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 	if (ret < 0) {
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 		dprintk(3, "buffer %d, plane %d failed to export (%d)\n",
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--- a/include/media/videobuf2-core.h
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+++ b/include/media/videobuf2-core.h
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@@ -870,6 +870,21 @@ int vb2_core_streamon(struct vb2_queue *
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 int vb2_core_streamoff(struct vb2_queue *q, unsigned int type);
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 /**
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+ * vb2_core_expbuf_dmabuf() - Export a buffer as a dma_buf structure
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+ * @q:         videobuf2 queue
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+ * @type:      buffer type
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+ * @index:     id number of the buffer
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+ * @plane:     index of the plane to be exported, 0 for single plane queues
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+ * @flags:     flags for newly created file, currently only O_CLOEXEC is
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+ *             supported, refer to manual of open syscall for more details
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+ * @dmabuf:    Returns the dmabuf pointer
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+ *
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+ */
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+int vb2_core_expbuf_dmabuf(struct vb2_queue *q, unsigned int type,
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+			   unsigned int index, unsigned int plane,
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+			   unsigned int flags, struct dma_buf **dmabuf);
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+
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+/**
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  * vb2_core_expbuf() - Export a buffer as a file descriptor.
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  * @q:		pointer to &struct vb2_queue with videobuf2 queue.
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  * @fd:		pointer to the file descriptor associated with DMABUF
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