dma-buf: Update [un]map documentation to match the other functions

Other function have inline documentation, a couple still have
theirs at the top of the structure, update the docs and move
them inline.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190321200957.16938-2-afd@ti.com

diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h
index e4a8dab..a0bd071 100644 (file)
--- a/include/linux/dma-buf.h
+++ b/include/linux/dma-buf.h
@@ -39,8 +39,6 @@ struct dma_buf_attachment;
 
 /**
  * struct dma_buf_ops - operations possible on struct dma_buf
- * @map: [optional] maps a page from the buffer into kernel address space.
- * @unmap: [optional] unmaps a page from the buffer.
  * @vmap: [optional] creates a virtual mapping for the buffer into kernel
  *       address space. Same restrictions as for vmap and friends apply.
  * @vunmap: [optional] unmaps a vmap from the buffer
@@ -200,8 +198,6 @@ struct dma_buf_ops {
         * to be restarted.
         */
        int (*end_cpu_access)(struct dma_buf *, enum dma_data_direction);
-       void *(*map)(struct dma_buf *, unsigned long);
-       void (*unmap)(struct dma_buf *, unsigned long, void *);
 
        /**
         * @mmap:
@@ -240,6 +236,31 @@ struct dma_buf_ops {
         */
        int (*mmap)(struct dma_buf *, struct vm_area_struct *vma);
 
+       /**
+        * @map:
+        *
+        * Maps a page from the buffer into kernel address space. The page is
+        * specified by offset into the buffer in PAGE_SIZE units.
+        *
+        * This callback is optional.
+        *
+        * Returns:
+        *
+        * Virtual address pointer where requested page can be accessed. NULL
+        * on error or when this function is unimplemented by the exporter.
+        */
+       void *(*map)(struct dma_buf *, unsigned long);
+
+       /**
+        * @unmap:
+        *
+        * Unmaps a page from the buffer. Page offset and address pointer should
+        * be the same as the one passed to and returned by matching call to map.
+        *
+        * This callback is optional.
+        */
+       void (*unmap)(struct dma_buf *, unsigned long, void *);
+
        void *(*vmap)(struct dma_buf *);
        void (*vunmap)(struct dma_buf *, void *vaddr);
 };