[PATCH] r/o bind mounts: unlink: monitor i_nlink

When a filesystem decrements i_nlink to zero, it means that a write must be
performed in order to drop the inode from the filesystem.

We're shortly going to have keep filesystems from being remounted r/o between
the time that this i_nlink decrement and that write occurs.

So, add a little helper function to do the decrements.  We'll tie into it in a
bit to note when i_nlink hits zero.

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, 5 deletions

diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 05f874c7441b..74441a17e186 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -590,7 +590,7 @@ int cifs_unlink(struct inode *inode, struct dentry *direntry)
 
         if (!rc) {
                 if (direntry->d_inode)
-                        direntry->d_inode->i_nlink--;
+                        drop_nlink(direntry->d_inode);
         } else if (rc == -ENOENT) {
                 d_drop(direntry);
         } else if (rc == -ETXTBSY) {
@@ -609,7 +609,7 @@ int cifs_unlink(struct inode *inode, struct dentry *direntry)
                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
                         CIFSSMBClose(xid, pTcon, netfid);
                         if (direntry->d_inode)
-                                direntry->d_inode->i_nlink--;
+                                drop_nlink(direntry->d_inode);
                 }
         } else if (rc == -EACCES) {
                 /* try only if r/o attribute set in local lookup data? */
@@ -663,7 +663,7 @@ int cifs_unlink(struct inode *inode, struct dentry *direntry)
                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
                         if (!rc) {
                                 if (direntry->d_inode)
-                                        direntry->d_inode->i_nlink--;
+                                        drop_nlink(direntry->d_inode);
                         } else if (rc == -ETXTBSY) {
                                 int oplock = FALSE;
                                 __u16 netfid;
@@ -684,7 +684,7 @@ int cifs_unlink(struct inode *inode, struct dentry *direntry)
                                                     CIFS_MOUNT_MAP_SPECIAL_CHR);
                                         CIFSSMBClose(xid, pTcon, netfid);
                                         if (direntry->d_inode)
-                                                direntry->d_inode->i_nlink--;
+                                                drop_nlink(direntry->d_inode);
                                 }
                         /* BB if rc = -ETXTBUSY goto the rename logic BB */
                         }
@@ -816,7 +816,7 @@ int cifs_rmdir(struct inode *inode, struct dentry *direntry)
                           cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 
         if (!rc) {
-                inode->i_nlink--;
+                drop_nlink(inode);
                 i_size_write(direntry->d_inode,0);
                 direntry->d_inode->i_nlink = 0;
         }