From 4fd699ae3fbca2ac760137e1d26f98a105f59f05 Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@redhat.com>
Date: Tue, 1 Apr 2014 17:08:43 +0200
Subject: [PATCH] vfs: lock_two_nondirectories: allow directory args
lock_two_nondirectories warned if either of its args was a directory.
Instead just ignore the directory args. This is needed for locking in
cross rename.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
---
fs/inode.c | 25 ++++++++++++-------------
1 file changed, 12 insertions(+), 13 deletions(-)
diff --git a/fs/inode.c b/fs/inode.c
index 4bcdad3c936129..73779c090f0d2e 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -944,24 +944,22 @@ EXPORT_SYMBOL(unlock_new_inode);
/**
* lock_two_nondirectories - take two i_mutexes on non-directory objects
+ *
+ * Lock any non-NULL argument that is not a directory.
+ * Zero, one or two objects may be locked by this function.
+ *
* @inode1: first inode to lock
* @inode2: second inode to lock
*/
void lock_two_nondirectories(struct inode *inode1, struct inode *inode2)
{
- WARN_ON_ONCE(S_ISDIR(inode1->i_mode));
- if (inode1 == inode2 || !inode2) {
- mutex_lock(&inode1->i_mutex);
- return;
- }
- WARN_ON_ONCE(S_ISDIR(inode2->i_mode));
- if (inode1 < inode2) {
+ if (inode1 > inode2)
+ swap(inode1, inode2);
+
+ if (inode1 && !S_ISDIR(inode1->i_mode))
mutex_lock(&inode1->i_mutex);
+ if (inode2 && !S_ISDIR(inode2->i_mode) && inode2 != inode1)
mutex_lock_nested(&inode2->i_mutex, I_MUTEX_NONDIR2);
- } else {
- mutex_lock(&inode2->i_mutex);
- mutex_lock_nested(&inode1->i_mutex, I_MUTEX_NONDIR2);
- }
}
EXPORT_SYMBOL(lock_two_nondirectories);
@@ -972,8 +970,9 @@ EXPORT_SYMBOL(lock_two_nondirectories);
*/
void unlock_two_nondirectories(struct inode *inode1, struct inode *inode2)
{
- mutex_unlock(&inode1->i_mutex);
- if (inode2 && inode2 != inode1)
+ if (inode1 && !S_ISDIR(inode1->i_mode))
+ mutex_unlock(&inode1->i_mutex);
+ if (inode2 && !S_ISDIR(inode2->i_mode) && inode2 != inode1)
mutex_unlock(&inode2->i_mutex);
}
EXPORT_SYMBOL(unlock_two_nondirectories);
--
GitLab