[media] vb2: replace 'write' by 'dma_dir'

The 'write' argument is very ambiguous. I first assumed that if it is 1,
then we're doing video output but instead it meant the reverse.

Since it is used to setup the dma_dir value anyway it is now replaced by
the correct dma_dir value which is unambiguous.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Pawel Osciak <pawel@osciak.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/v4l2-core/videobuf2-core.c

@@ -1358,7 +1358,8 @@ static int __qbuf_userptr(struct vb2_buffer *vb, const struct v4l2_buffer *b)
 	void *mem_priv;
 	unsigned int plane;
 	int ret;
-	int write = !V4L2_TYPE_IS_OUTPUT(q->type);
+	enum dma_data_direction dma_dir =
+		V4L2_TYPE_IS_OUTPUT(q->type) ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
 	bool reacquired = vb->planes[0].mem_priv == NULL;
 
 	memset(planes, 0, sizeof(planes[0]) * vb->num_planes);
@@ -1400,7 +1401,7 @@ static int __qbuf_userptr(struct vb2_buffer *vb, const struct v4l2_buffer *b)
 		/* Acquire each plane's memory */
 		mem_priv = call_ptr_memop(vb, get_userptr, q->alloc_ctx[plane],
 				      planes[plane].m.userptr,
-				      planes[plane].length, write);
+				      planes[plane].length, dma_dir);
 		if (IS_ERR_OR_NULL(mem_priv)) {
 			dprintk(1, "failed acquiring userspace "
 						"memory for plane %d\n", plane);
@@ -1461,7 +1462,8 @@ static int __qbuf_dmabuf(struct vb2_buffer *vb, const struct v4l2_buffer *b)
 	void *mem_priv;
 	unsigned int plane;
 	int ret;
-	int write = !V4L2_TYPE_IS_OUTPUT(q->type);
+	enum dma_data_direction dma_dir =
+		V4L2_TYPE_IS_OUTPUT(q->type) ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
 	bool reacquired = vb->planes[0].mem_priv == NULL;
 
 	memset(planes, 0, sizeof(planes[0]) * vb->num_planes);
@@ -1509,7 +1511,7 @@ static int __qbuf_dmabuf(struct vb2_buffer *vb, const struct v4l2_buffer *b)
 
 		/* Acquire each plane's memory */
 		mem_priv = call_ptr_memop(vb, attach_dmabuf, q->alloc_ctx[plane],
-			dbuf, planes[plane].length, write);
+			dbuf, planes[plane].length, dma_dir);
 		if (IS_ERR(mem_priv)) {
 			dprintk(1, "failed to attach dmabuf\n");
 			ret = PTR_ERR(mem_priv);

drivers/media/v4l2-core/videobuf2-dma-contig.c

@@ -229,7 +229,7 @@ static int vb2_dc_mmap(void *buf_priv, struct vm_area_struct *vma)
 
 struct vb2_dc_attachment {
 	struct sg_table sgt;
-	enum dma_data_direction dir;
+	enum dma_data_direction dma_dir;
 };
 
 static int vb2_dc_dmabuf_ops_attach(struct dma_buf *dbuf, struct device *dev,
@@ -264,7 +264,7 @@ static int vb2_dc_dmabuf_ops_attach(struct dma_buf *dbuf, struct device *dev,
 		wr = sg_next(wr);
 	}
 
-	attach->dir = DMA_NONE;
+	attach->dma_dir = DMA_NONE;
 	dbuf_attach->priv = attach;
 
 	return 0;
@@ -282,16 +282,16 @@ static void vb2_dc_dmabuf_ops_detach(struct dma_buf *dbuf,
 	sgt = &attach->sgt;
 
 	/* release the scatterlist cache */
-	if (attach->dir != DMA_NONE)
+	if (attach->dma_dir != DMA_NONE)
 		dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
-			attach->dir);
+			attach->dma_dir);
 	sg_free_table(sgt);
 	kfree(attach);
 	db_attach->priv = NULL;
 }
 
 static struct sg_table *vb2_dc_dmabuf_ops_map(
-	struct dma_buf_attachment *db_attach, enum dma_data_direction dir)
+	struct dma_buf_attachment *db_attach, enum dma_data_direction dma_dir)
 {
 	struct vb2_dc_attachment *attach = db_attach->priv;
 	/* stealing dmabuf mutex to serialize map/unmap operations */
@@ -303,27 +303,27 @@ static struct sg_table *vb2_dc_dmabuf_ops_map(
 
 	sgt = &attach->sgt;
 	/* return previously mapped sg table */
-	if (attach->dir == dir) {
+	if (attach->dma_dir == dma_dir) {
 		mutex_unlock(lock);
 		return sgt;
 	}
 
 	/* release any previous cache */
-	if (attach->dir != DMA_NONE) {
+	if (attach->dma_dir != DMA_NONE) {
 		dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents,
-			attach->dir);
-		attach->dir = DMA_NONE;
+			attach->dma_dir);
+		attach->dma_dir = DMA_NONE;
 	}
 
 	/* mapping to the client with new direction */
-	ret = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, dir);
+	ret = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, dma_dir);
 	if (ret <= 0) {
 		pr_err("failed to map scatterlist\n");
 		mutex_unlock(lock);
 		return ERR_PTR(-EIO);
 	}
 
-	attach->dir = dir;
+	attach->dma_dir = dma_dir;
 
 	mutex_unlock(lock);
 
@@ -331,7 +331,7 @@ static struct sg_table *vb2_dc_dmabuf_ops_map(
 }
 
 static void vb2_dc_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach,
-	struct sg_table *sgt, enum dma_data_direction dir)
+	struct sg_table *sgt, enum dma_data_direction dma_dir)
 {
 	/* nothing to be done here */
 }
@@ -460,7 +460,8 @@ static int vb2_dc_get_user_pfn(unsigned long start, int n_pages,
 }
 
 static int vb2_dc_get_user_pages(unsigned long start, struct page **pages,
-	int n_pages, struct vm_area_struct *vma, int write)
+	int n_pages, struct vm_area_struct *vma,
+	enum dma_data_direction dma_dir)
 {
 	if (vma_is_io(vma)) {
 		unsigned int i;
@@ -482,7 +483,7 @@ static int vb2_dc_get_user_pages(unsigned long start, struct page **pages,
 		int n;
 
 		n = get_user_pages(current, current->mm, start & PAGE_MASK,
-			n_pages, write, 1, pages, NULL);
+			n_pages, dma_dir == DMA_FROM_DEVICE, 1, pages, NULL);
 		/* negative error means that no page was pinned */
 		n = max(n, 0);
 		if (n != n_pages) {
@@ -551,7 +552,7 @@ static inline dma_addr_t vb2_dc_pfn_to_dma(struct device *dev, unsigned long pfn
 #endif
 
 static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr,
-	unsigned long size, int write)
+	unsigned long size, enum dma_data_direction dma_dir)
 {
 	struct vb2_dc_conf *conf = alloc_ctx;
 	struct vb2_dc_buf *buf;
@@ -582,7 +583,7 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr,
 		return ERR_PTR(-ENOMEM);
 
 	buf->dev = conf->dev;
-	buf->dma_dir = write ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
+	buf->dma_dir = dma_dir;
 
 	start = vaddr & PAGE_MASK;
 	offset = vaddr & ~PAGE_MASK;
@@ -618,7 +619,8 @@ static void *vb2_dc_get_userptr(void *alloc_ctx, unsigned long vaddr,
 	}
 
 	/* extract page list from userspace mapping */
-	ret = vb2_dc_get_user_pages(start, pages, n_pages, vma, write);
+	ret = vb2_dc_get_user_pages(start, pages, n_pages, vma,
+				    dma_dir == DMA_FROM_DEVICE);
 	if (ret) {
 		unsigned long pfn;
 		if (vb2_dc_get_user_pfn(start, n_pages, vma, &pfn) == 0) {
@@ -782,7 +784,7 @@ static void vb2_dc_detach_dmabuf(void *mem_priv)
 }
 
 static void *vb2_dc_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf,
-	unsigned long size, int write)
+	unsigned long size, enum dma_data_direction dma_dir)
 {
 	struct vb2_dc_conf *conf = alloc_ctx;
 	struct vb2_dc_buf *buf;
@@ -804,7 +806,7 @@ static void *vb2_dc_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf,
 		return dba;
 	}
 
-	buf->dma_dir = write ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
+	buf->dma_dir = dma_dir;
 	buf->size = size;
 	buf->db_attach = dba;
 

drivers/media/v4l2-core/videobuf2-dma-sg.c

@@ -33,8 +33,8 @@ module_param(debug, int, 0644);
 struct vb2_dma_sg_buf {
 	void				*vaddr;
 	struct page			**pages;
-	int				write;
 	int				offset;
+	enum dma_data_direction		dma_dir;
 	struct sg_table			sg_table;
 	size_t				size;
 	unsigned int			num_pages;
@@ -97,7 +97,7 @@ static void *vb2_dma_sg_alloc(void *alloc_ctx, unsigned long size, gfp_t gfp_fla
 		return NULL;
 
 	buf->vaddr = NULL;
-	buf->write = 0;
+	buf->dma_dir = DMA_NONE;
 	buf->offset = 0;
 	buf->size = size;
 	/* size is already page aligned */
@@ -162,7 +162,8 @@ static inline int vma_is_io(struct vm_area_struct *vma)
 }
 
 static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
-				    unsigned long size, int write)
+				    unsigned long size,
+				    enum dma_data_direction dma_dir)
 {
 	struct vb2_dma_sg_buf *buf;
 	unsigned long first, last;
@@ -174,7 +175,7 @@ static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
 		return NULL;
 
 	buf->vaddr = NULL;
-	buf->write = write;
+	buf->dma_dir = dma_dir;
 	buf->offset = vaddr & ~PAGE_MASK;
 	buf->size = size;
 
@@ -221,7 +222,7 @@ static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
 		num_pages_from_user = get_user_pages(current, current->mm,
 					     vaddr & PAGE_MASK,
 					     buf->num_pages,
-					     write,
+					     buf->dma_dir == DMA_FROM_DEVICE,
 					     1, /* force */
 					     buf->pages,
 					     NULL);
@@ -265,7 +266,7 @@ static void vb2_dma_sg_put_userptr(void *buf_priv)
 		vm_unmap_ram(buf->vaddr, buf->num_pages);
 	sg_free_table(&buf->sg_table);
 	while (--i >= 0) {
-		if (buf->write)
+		if (buf->dma_dir == DMA_FROM_DEVICE)
 			set_page_dirty_lock(buf->pages[i]);
 		if (!vma_is_io(buf->vma))
 			put_page(buf->pages[i]);

drivers/media/v4l2-core/videobuf2-vmalloc.c

@@ -25,7 +25,7 @@ struct vb2_vmalloc_buf {
 	void				*vaddr;
 	struct page			**pages;
 	struct vm_area_struct		*vma;
-	int				write;
+	enum dma_data_direction		dma_dir;
 	unsigned long			size;
 	unsigned int			n_pages;
 	atomic_t			refcount;
@@ -70,7 +70,8 @@ static void vb2_vmalloc_put(void *buf_priv)
 }
 
 static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr,
-				     unsigned long size, int write)
+				     unsigned long size,
+				     enum dma_data_direction dma_dir)
 {
 	struct vb2_vmalloc_buf *buf;
 	unsigned long first, last;
@@ -82,7 +83,7 @@ static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr,
 	if (!buf)
 		return NULL;
 
-	buf->write = write;
+	buf->dma_dir = dma_dir;
 	offset = vaddr & ~PAGE_MASK;
 	buf->size = size;
 
@@ -107,7 +108,8 @@ static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr,
 		/* current->mm->mmap_sem is taken by videobuf2 core */
 		n_pages = get_user_pages(current, current->mm,
 					 vaddr & PAGE_MASK, buf->n_pages,
-					 write, 1, /* force */
+					 dma_dir == DMA_FROM_DEVICE,
+					 1, /* force */
 					 buf->pages, NULL);
 		if (n_pages != buf->n_pages)
 			goto fail_get_user_pages;
@@ -144,7 +146,7 @@ static void vb2_vmalloc_put_userptr(void *buf_priv)
 		if (vaddr)
 			vm_unmap_ram((void *)vaddr, buf->n_pages);
 		for (i = 0; i < buf->n_pages; ++i) {
-			if (buf->write)
+			if (buf->dma_dir == DMA_FROM_DEVICE)
 				set_page_dirty_lock(buf->pages[i]);
 			put_page(buf->pages[i]);
 		}
@@ -240,7 +242,7 @@ static void vb2_vmalloc_detach_dmabuf(void *mem_priv)
 }
 
 static void *vb2_vmalloc_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf,
-	unsigned long size, int write)
+	unsigned long size, enum dma_data_direction dma_dir)
 {
 	struct vb2_vmalloc_buf *buf;
 
@@ -252,7 +254,7 @@ static void *vb2_vmalloc_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf,
 		return ERR_PTR(-ENOMEM);
 
 	buf->dbuf = dbuf;
-	buf->write = write;
+	buf->dma_dir = dma_dir;
 	buf->size = size;
 
 	return buf;

include/media/videobuf2-core.h

@@ -87,14 +87,16 @@ struct vb2_mem_ops {
 	struct dma_buf *(*get_dmabuf)(void *buf_priv, unsigned long flags);
 
 	void		*(*get_userptr)(void *alloc_ctx, unsigned long vaddr,
-					unsigned long size, int write);
+					unsigned long size,
+					enum dma_data_direction dma_dir);
 	void		(*put_userptr)(void *buf_priv);
 
 	void		(*prepare)(void *buf_priv);
 	void		(*finish)(void *buf_priv);
 
 	void		*(*attach_dmabuf)(void *alloc_ctx, struct dma_buf *dbuf,
-				unsigned long size, int write);
+					  unsigned long size,
+					  enum dma_data_direction dma_dir);
 	void		(*detach_dmabuf)(void *buf_priv);
 	int		(*map_dmabuf)(void *buf_priv);
 	void		(*unmap_dmabuf)(void *buf_priv);