[v9,21/34] vfs: allow setxattr to retry once on ESTALE errors

Commit Message

Jeff Layton Nov. 5, 2012, 3:22 p.m. UTC

Signed-off-by: Jeff Layton <[e-mail]>
---
 fs/xattr.c | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

Patch

diff --git a/fs/xattr.c b/fs/xattr.c
index f3a2ffa..5b6e48d 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -370,16 +370,21 @@  SYSCALL_DEFINE5(setxattr, const char __user *, pathname,
 {
 	struct path path;
 	int error;
+	unsigned int try = 0;
+	unsigned int lookup_flags = LOOKUP_FOLLOW;
 
-	error = user_path(pathname, &path);
-	if (error)
-		return error;
-	error = mnt_want_write(path.mnt);
-	if (!error) {
-		error = setxattr(path.dentry, name, value, size, flags);
-		mnt_drop_write(path.mnt);
-	}
-	path_put(&path);
+	do {
+		error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
+		if (error)
+			break;
+		error = mnt_want_write(path.mnt);
+		if (!error) {
+			error = setxattr(path.dentry, name, value, size, flags);
+			mnt_drop_write(path.mnt);
+		}
+		path_put(&path);
+		lookup_flags |= LOOKUP_REVAL;
+	} while (retry_estale(error, try++));
 	return error;
 }