[PATCH v3 09/17] vfs: fix mkdir to retry on ESTALE errors

[Jeff Layton <jlayton@redhat.com>]

Signed-off-by: Jeff Layton <jlayton@redhat.com>
---
 fs/namei.c |   43 ++++++++++++++++++++++++++-----------------
 1 files changed, 26 insertions(+), 17 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index ef3ccee..dec5713 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2744,26 +2744,35 @@ SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode)
 	struct dentry *dentry;
 	struct path path;
 	int error;
+	char *name;
+	unsigned int try = 0;
 
-	dentry = user_path_create(dfd, pathname, &path, 1);
-	if (IS_ERR(dentry))
-		return PTR_ERR(dentry);
-
-	if (!IS_POSIXACL(path.dentry->d_inode))
-		mode &= ~current_umask();
-	error = mnt_want_write(path.mnt);
-	if (error)
-		goto out_dput;
-	error = security_path_mkdir(&path, dentry, mode);
-	if (error)
-		goto out_drop_write;
-	error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
+	name = getname(pathname);
+	if (IS_ERR(name))
+		return PTR_ERR(name);
+	do {
+		dentry = kern_path_create(dfd, name, &path, true, try);
+		if (IS_ERR(dentry)) {
+			error = PTR_ERR(dentry);
+			break;
+		}
+		if (!IS_POSIXACL(path.dentry->d_inode))
+			mode &= ~current_umask();
+		error = mnt_want_write(path.mnt);
+		if (error)
+			goto out_dput;
+		error = security_path_mkdir(&path, dentry, mode);
+		if (error)
+			goto out_drop_write;
+		error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
 out_drop_write:
-	mnt_drop_write(path.mnt);
+		mnt_drop_write(path.mnt);
 out_dput:
-	dput(dentry);
-	mutex_unlock(&path.dentry->d_inode->i_mutex);
-	path_put(&path);
+		dput(dentry);
+		mutex_unlock(&path.dentry->d_inode->i_mutex);
+		path_put(&path);
+	} while (retry_estale(error, try++));
+	putname(name);
 	return error;
 }
 
-- 
1.7.7.6