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, 1 deletions

diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 9876a87255fe..01353ed75750 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -866,6 +866,8 @@ static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
                                 fc->auto_inval_data = 1;
                         if (arg->flags & FUSE_DO_READDIRPLUS)
                                 fc->do_readdirplus = 1;
+                        if (arg->flags & FUSE_READDIRPLUS_AUTO)
+                                fc->readdirplus_auto = 1;
                 } else {
                         ra_pages = fc->max_read / PAGE_CACHE_SIZE;
                         fc->no_lock = 1;
@@ -893,7 +895,7 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
                 FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK |
                 FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ |
                 FUSE_FLOCK_LOCKS | FUSE_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
-                FUSE_DO_READDIRPLUS;
+                FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO;
         req->in.h.opcode = FUSE_INIT;
         req->in.numargs = 1;
         req->in.args[0].size = sizeof(*arg);