dma-buf: Add debugfs support

Add debugfs support to make it easier to print debug information
about the dma-buf buffers.

Cc: Dave Airlie <airlied@redhat.com>
 [minor fixes on init and warning fix]
Cc: Dan Carpenter <dan.carpenter@oracle.com>
 [remove double unlock in fail case]
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>

1 files changed, 4 insertions, 1 deletions

diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h
index 6f55c0424f12..dfac5ed31120 100644
--- a/include/linux/dma-buf.h
+++ b/include/linux/dma-buf.h
@@ -113,6 +113,7 @@ struct dma_buf_ops {
  * @attachments: list of dma_buf_attachment that denotes all devices attached.
  * @ops: dma_buf_ops associated with this buffer object.
  * @exp_name: name of the exporter; useful for debugging.
+ * @list_node: node for dma_buf accounting and debugging.
  * @priv: exporter specific private data for this buffer object.
  */
 struct dma_buf {
@@ -125,6 +126,7 @@ struct dma_buf {
         unsigned vmapping_counter;
         void *vmap_ptr;
         const char *exp_name;
+        struct list_head list_node;
         void *priv;
 };
 
@@ -192,5 +194,6 @@ int dma_buf_mmap(struct dma_buf *, struct vm_area_struct *,
                  unsigned long);
 void *dma_buf_vmap(struct dma_buf *);
 void dma_buf_vunmap(struct dma_buf *, void *vaddr);
-
+int dma_buf_debugfs_create_file(const char *name,
+                                int (*write)(struct seq_file *));
 #endif /* __DMA_BUF_H__ */