[PATCH] r/o bind mounts: monitor zeroing of i_nlink

Some filesystems, instead of simply decrementing i_nlink, simply zero it
during an unlink operation.  We need to catch these in addition to the
decrement operations.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 6a5267da565f..3493d2828f7d 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1235,6 +1235,11 @@ static inline void drop_nlink(struct inode *inode)
         inode->i_nlink--;
 }
 
+static inline void clear_nlink(struct inode *inode)
+{
+        inode->i_nlink = 0;
+}
+
 static inline void inode_dec_link_count(struct inode *inode)
 {
         drop_nlink(inode);