[PATCH v3 2/9] dma-buf: Add locked variant of dma_buf_vmap/vunmap()

Dmitry Osipenko
2022-08-24T10:23:57Z

Add locked variant of dma_buf_vmap/vunmap() that will be utilized by
DRM drivers once vmap/unmap functions will be moved to the new locking
convention.

Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
---
drivers/dma-buf/dma-buf.c | 42 +++++++++++++++++++++++++++++++++++----
include/linux/dma-buf.h | 2 ++
2 files changed, 40 insertions(+), 4 deletions(-)

diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index 452a6a1f1e60..34173aafe6c9 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -1373,7 +1373,7 @@ int dma_buf_mmap_unlocked(struct dma_buf *dmabuf, struct vm_area_struct *vma,
EXPORT_SYMBOL_NS_GPL(dma_buf_mmap_unlocked, DMA_BUF);

/**
- * dma_buf_vmap_unlocked - Create virtual mapping for the buffer object into kernel
+ * dma_buf_vmap - 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
@@ -1388,7 +1388,7 @@ EXPORT_SYMBOL_NS_GPL(dma_buf_mmap_unlocked, DMA_BUF);
*
* Returns 0 on success, or a negative errno code otherwise.
*/
-int dma_buf_vmap_unlocked(struct dma_buf *dmabuf, struct iosys_map *map)
+int dma_buf_vmap(struct dma_buf *dmabuf, struct iosys_map *map)
{
struct iosys_map ptr;
int ret = 0;
@@ -1424,14 +1424,34 @@ int dma_buf_vmap_unlocked(struct dma_buf *dmabuf, struct iosys_map *map)
mutex_unlock(&dmabuf->lock);
return ret;
}
+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;
+
+ ret = dma_buf_vmap(dmabuf, map);
+
+ return ret;
+}
EXPORT_SYMBOL_NS_GPL(dma_buf_vmap_unlocked, DMA_BUF);

/**
- * dma_buf_vunmap_unlocked - Unmap a vmap obtained by dma_buf_vmap.
+ * dma_buf_vunmap - 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)
+void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map)
{
if (WARN_ON(!dmabuf))
return;
@@ -1448,6 +1468,20 @@ void dma_buf_vunmap_unlocked(struct dma_buf *dmabuf, struct iosys_map *map)
}
mutex_unlock(&dmabuf->lock);
}
+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_buf_vunmap(dmabuf, map);
+}
EXPORT_SYMBOL_NS_GPL(dma_buf_vunmap_unlocked, DMA_BUF);

#ifdef CONFIG_DEBUG_FS
diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h
index 9ab09569dec1..da2057569101 100644
--- a/include/linux/dma-buf.h
+++ b/include/linux/dma-buf.h
@@ -636,4 +636,6 @@ int dma_buf_mmap_unlocked(struct dma_buf *, struct vm_area_struct *,
unsigned long);
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);
+int dma_buf_vmap(struct dma_buf *dmabuf, struct iosys_map *map);
+void dma_buf_vunmap(struct dma_buf *dmabuf, struct iosys_map *map);
#endif /* __DMA_BUF_H__ */
--
2.37.2