Commit 56e5abba authored by Dmitry Osipenko's avatar Dmitry Osipenko
Browse files

dma-buf: Add unlocked variant of vmapping functions 



Add unlocked variant of dma_buf_vmap/vunmap() that will be utilized
by drivers that don't take the reservation lock explicitly.

Acked-by: default avatarSumit Semwal <sumit.semwal@linaro.org>
Acked-by: default avatarChristian König <christian.koenig@amd.com>
Signed-off-by: default avatarDmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221017172229.42269-2-dmitry.osipenko@collabora.com
parent f8ced2ab

drivers/dma-buf/dma-buf.c

+43 −0
Original line number Diff line number Diff line
@@ -1425,6 +1425,33 @@ int dma_buf_vmap(struct dma_buf *dmabuf, struct iosys_map *map) 
}

EXPORT_SYMBOL_NS_GPL(dma_buf_vmap, DMA_BUF);



/**

 * dma_buf_vmap_unlocked - Create virtual mapping for the buffer object into kernel

 * address space. Same restrictions as for vmap and friends apply.

 * @dmabuf:	[in]	buffer to vmap

 * @map:	[out]	returns the vmap pointer

 *

 * Unlocked version of dma_buf_vmap()

 *

 * Returns 0 on success, or a negative errno code otherwise.

 */

int dma_buf_vmap_unlocked(struct dma_buf *dmabuf, struct iosys_map *map)

{

	int ret;



	iosys_map_clear(map);



	if (WARN_ON(!dmabuf))

		return -EINVAL;



	dma_resv_lock(dmabuf->resv, NULL);

	ret = dma_buf_vmap(dmabuf, map);

	dma_resv_unlock(dmabuf->resv);



	return ret;

}

EXPORT_SYMBOL_NS_GPL(dma_buf_vmap_unlocked, DMA_BUF);



/**

 * dma_buf_vunmap - Unmap a vmap obtained by dma_buf_vmap.

 * @dmabuf:	[in]	buffer to vunmap
@@ -1449,6 +1476,22 @@ void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map) 
}

EXPORT_SYMBOL_NS_GPL(dma_buf_vunmap, DMA_BUF);



/**

 * dma_buf_vunmap_unlocked - Unmap a vmap obtained by dma_buf_vmap.

 * @dmabuf:	[in]	buffer to vunmap

 * @map:	[in]	vmap pointer to vunmap

 */

void dma_buf_vunmap_unlocked(struct dma_buf *dmabuf, struct iosys_map *map)

{

	if (WARN_ON(!dmabuf))

		return;



	dma_resv_lock(dmabuf->resv, NULL);

	dma_buf_vunmap(dmabuf, map);

	dma_resv_unlock(dmabuf->resv);

}

EXPORT_SYMBOL_NS_GPL(dma_buf_vunmap_unlocked, DMA_BUF);



#ifdef CONFIG_DEBUG_FS

static int dma_buf_debug_show(struct seq_file *s, void *unused)

{

include/linux/dma-buf.h

+2 −0
Original line number Diff line number Diff line
@@ -632,4 +632,6 @@ int dma_buf_mmap(struct dma_buf *, struct vm_area_struct *, 
		 unsigned long);

int dma_buf_vmap(struct dma_buf *dmabuf, struct iosys_map *map);

void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map);

int dma_buf_vmap_unlocked(struct dma_buf *dmabuf, struct iosys_map *map);

void dma_buf_vunmap_unlocked(struct dma_buf *dmabuf, struct iosys_map *map);

#endif /* __DMA_BUF_H__ */