Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Assorted fixes, sat in -next for a week or so...

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ocfs2: deal with wraparounds of i_nlink in ocfs2_rename()
  vfs: fix compat_sys_stat() handling of overflows in st_nlink
  quota: Fix deadlock with suspend and quotas
  vfs: Provide function to get superblock and wait for it to thaw
  vfs: fix panic in __d_lookup() with high dentry hashtable counts
  autofs4 - fix lockdep splat in autofs
  vfs: fix d_inode_lookup() dentry ref leak

1 files changed, 21 insertions, 3 deletions

diff --git a/fs/quota/quota.c b/fs/quota/quota.c
index 7898cd688a00..fc2c4388d126 100644
--- a/fs/quota/quota.c
+++ b/fs/quota/quota.c
@@ -292,11 +292,26 @@ static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
 	}
 }
 
+/* Return 1 if 'cmd' will block on frozen filesystem */
+static int quotactl_cmd_write(int cmd)
+{
+	switch (cmd) {
+	case Q_GETFMT:
+	case Q_GETINFO:
+	case Q_SYNC:
+	case Q_XGETQSTAT:
+	case Q_XGETQUOTA:
+	case Q_XQUOTASYNC:
+		return 0;
+	}
+	return 1;
+}
+
 /*
  * look up a superblock on which quota ops will be performed
  * - use the name of a block device to find the superblock thereon
  */
-static struct super_block *quotactl_block(const char __user *special)
+static struct super_block *quotactl_block(const char __user *special, int cmd)
 {
 #ifdef CONFIG_BLOCK
 	struct block_device *bdev;
@@ -309,7 +324,10 @@ static struct super_block *quotactl_block(const char __user *special)
 	putname(tmp);
 	if (IS_ERR(bdev))
 		return ERR_CAST(bdev);
-	sb = get_super(bdev);
+	if (quotactl_cmd_write(cmd))
+		sb = get_super_thawed(bdev);
+	else
+		sb = get_super(bdev);
 	bdput(bdev);
 	if (!sb)
 		return ERR_PTR(-ENODEV);
@@ -361,7 +379,7 @@ SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
 			pathp = &path;
 	}
 
-	sb = quotactl_block(special);
+	sb = quotactl_block(special, cmds);
 	if (IS_ERR(sb)) {
 		ret = PTR_ERR(sb);
 		goto out;