From: Al Viro <viro@zeniv.linux.org.uk>
Date: Thu, 14 Apr 2016 23:12:42 +0000 (-0400)
Subject: reconnect_one(): use lookup_one_len_unlocked()
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=383d4e8ab02c02f7b31f90174c644d935c223c85;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

reconnect_one(): use lookup_one_len_unlocked()

... and explain the non-obvious logics in case when lookup yields
a different dentry.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c
index c46f1a190b8d..402c5caab5ca 100644
--- a/fs/exportfs/expfs.c
+++ b/fs/exportfs/expfs.c
@@ -143,14 +143,18 @@ static struct dentry *reconnect_one(struct vfsmount *mnt,
 	if (err)
 		goto out_err;
 	dprintk("%s: found name: %s\n", __func__, nbuf);
-	inode_lock(parent->d_inode);
-	tmp = lookup_one_len(nbuf, parent, strlen(nbuf));
-	inode_unlock(parent->d_inode);
+	tmp = lookup_one_len_unlocked(nbuf, parent, strlen(nbuf));
 	if (IS_ERR(tmp)) {
 		dprintk("%s: lookup failed: %d\n", __func__, PTR_ERR(tmp));
 		goto out_err;
 	}
 	if (tmp != dentry) {
+		/*
+		 * Somebody has renamed it since exportfs_get_name();
+		 * great, since it could've only been renamed if it
+		 * got looked up and thus connected, and it would
+		 * remain connected afterwards.  We are done.
+		 */
 		dput(tmp);
 		goto out_reconnected;
 	}