fuse: add atomic open+truncate support

This patch allows fuse filesystems to implement open(..., O_TRUNC) as a single
request, instead of separate truncate and open requests.

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, 3 insertions, 1 deletions

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 4a28c3d37732..6726378661da 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -28,7 +28,9 @@ static int fuse_send_open(struct inode *inode, struct file *file, int isdir,
                 return PTR_ERR(req);
 
         memset(&inarg, 0, sizeof(inarg));
-        inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
+        inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY);
+        if (!fc->atomic_o_trunc)
+                inarg.flags &= ~O_TRUNC;
         req->in.h.opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
         req->in.h.nodeid = get_node_id(inode);
         req->in.numargs = 1;