[PATCH v7 32/49] vfs: fix renameat to retry on ESTALE errors

Jeff Layton
2012-10-02T00:17:52Z

...as always, rename is the messiest of the bunch. We have to track
whether to retry or not via a separate flag since the error handling
is already quite complex.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
---
fs/namei.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index f311ed1..dfdcd47 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3851,15 +3851,18 @@ SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname,
struct nameidata oldnd, newnd;
struct getname_info *from;
struct getname_info *to;
+ unsigned int try = 0;
+ bool should_retry = false;
int error;

- from = user_path_parent(olddfd, oldname, &oldnd, 0);
+retry:
+ from = user_path_parent(olddfd, oldname, &oldnd, try);
if (IS_ERR(from)) {
error = PTR_ERR(from);
goto exit;
}

- to = user_path_parent(newdfd, newname, &newnd, 0);
+ to = user_path_parent(newdfd, newname, &newnd, try);
if (IS_ERR(to)) {
error = PTR_ERR(to);
goto exit1;
@@ -3931,11 +3934,17 @@ exit3:
unlock_rename(new_dir, old_dir);
mnt_drop_write(oldnd.path.mnt);
exit2:
+ if (retry_estale(error, try++))
+ should_retry = true;
path_put(&newnd.path);
putname(to);
exit1:
path_put(&oldnd.path);
putname(from);
+ if (should_retry) {
+ should_retry = false;
+ goto retry;
+ }
exit:
return error;
}
--
1.7.11.4