fuse: add helper for asynchronous writes

This patch adds a new helper function fuse_write_fill() which makes it
possible to send WRITE requests asynchronously.

A new flag for WRITE requests is also added which indicates that this a write
from the page cache, and not a "normal" file write.

This patch is in preparation for writable mmap support.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/include/linux/fuse.h b/include/linux/fuse.h
index 015a8b15a388..6f4a31266cd5 100644
--- a/include/linux/fuse.h
+++ b/include/linux/fuse.h
@@ -119,6 +119,13 @@ struct fuse_file_lock {
  */
 #define FUSE_LK_FLOCK           (1 << 0)
 
+/**
+ * WRITE flags
+ *
+ * FUSE_WRITE_CACHE: delayed write from page cache, file handle is guessed
+ */
+#define FUSE_WRITE_CACHE        (1 << 0)
+
 enum fuse_opcode {
         FUSE_LOOKUP        = 1,
         FUSE_FORGET        = 2,  /* no reply */