If the fast lookup fails, then return -EAGAIN to have the caller retry
the path lookup. This is in preparation for supporting non-blocking
open.
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
fs/namei.c | 2 ++
include/linux/namei.h | 1 +
2 files changed, 3 insertions(+)
diff --git a/fs/namei.c b/fs/namei.c
index 2dda552bcf7a..50899721f699 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1801,6 +1801,8 @@ static int walk_component(struct nameidata *nd, int flags)
if (unlikely(err <= 0)) {
if (err < 0)
return err;
+ if (nd->flags & LOOKUP_NONBLOCK)
+ return -EAGAIN;
path.dentry = lookup_slow(&nd->last, nd->path.dentry,
nd->flags);
if (IS_ERR(path.dentry))
diff --git a/include/linux/namei.h b/include/linux/namei.h
index 397a08ade6a2..a50ad21e3457 100644
--- a/include/linux/namei.h
+++ b/include/linux/namei.h
@@ -38,6 +38,7 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND};
#define LOOKUP_JUMPED 0x1000
#define LOOKUP_ROOT 0x2000
#define LOOKUP_ROOT_GRABBED 0x0008
+#define LOOKUP_NONBLOCK 0x10000 /* don't block for lookup */
extern int path_pts(struct path *path);
--
2.24.1
