fuse: allow control of adaptive readdirplus use

For some filesystems (e.g. GlusterFS), the cost of performing a
normal readdir and readdirplus are identical.  Since adaptively
using readdirplus has no benefit for those systems, give
users/filesystems the option to control adaptive readdirplus use.

v2 of this patch incorporates Miklos's suggestion to simplify the code,
as well as improving consistency of macro names and documentation.

Signed-off-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/uapi/linux/fuse.h b/include/uapi/linux/fuse.h
index baee03e90438..4c43b4448792 100644
--- a/include/uapi/linux/fuse.h
+++ b/include/uapi/linux/fuse.h
@@ -218,6 +218,8 @@ struct fuse_file_lock {
  * FUSE_FLOCK_LOCKS: remote locking for BSD style file locks
  * FUSE_HAS_IOCTL_DIR: kernel supports ioctl on directories
  * FUSE_AUTO_INVAL_DATA: automatically invalidate cached pages
+ * FUSE_DO_READDIRPLUS: do READDIRPLUS (READDIR+LOOKUP in one)
+ * FUSE_READDIRPLUS_AUTO: adaptive readdirplus
  */
 #define FUSE_ASYNC_READ         (1 << 0)
 #define FUSE_POSIX_LOCKS        (1 << 1)
@@ -233,6 +235,7 @@ struct fuse_file_lock {
 #define FUSE_HAS_IOCTL_DIR      (1 << 11)
 #define FUSE_AUTO_INVAL_DATA    (1 << 12)
 #define FUSE_DO_READDIRPLUS     (1 << 13)
+#define FUSE_READDIRPLUS_AUTO   (1 << 14)
 
 /**
  * CUSE INIT request/reply flags