From: "Theodore Ts'o" <tytso@mit.edu>

Move the i_cdev pointer in struct inode into a union.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 fs/file_table.c    |    2 +-
 fs/inode.c         |    2 +-
 include/linux/fs.h |    2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff -puN fs/file_table.c~inode-diet-move-i_cdev-into-a-union fs/file_table.c
--- a/fs/file_table.c~inode-diet-move-i_cdev-into-a-union
+++ a/fs/file_table.c
@@ -169,7 +169,7 @@ void fastcall __fput(struct file *file)
 	if (file->f_op && file->f_op->release)
 		file->f_op->release(inode, file);
 	security_file_free(file);
-	if (unlikely(inode->i_cdev != NULL))
+	if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL))
 		cdev_put(inode->i_cdev);
 	fops_put(file->f_op);
 	if (file->f_mode & FMODE_WRITE)
diff -puN fs/inode.c~inode-diet-move-i_cdev-into-a-union fs/inode.c
--- a/fs/inode.c~inode-diet-move-i_cdev-into-a-union
+++ a/fs/inode.c
@@ -256,7 +256,7 @@ void clear_inode(struct inode *inode)
 		inode->i_sb->s_op->clear_inode(inode);
 	if (S_ISBLK(inode->i_mode) && inode->i_bdev)
 		bd_forget(inode);
-	if (inode->i_cdev)
+	if (S_ISCHR(inode->i_mode) && inode->i_cdev)
 		cd_forget(inode);
 	inode->i_state = I_CLEAR;
 }
diff -puN include/linux/fs.h~inode-diet-move-i_cdev-into-a-union include/linux/fs.h
--- a/include/linux/fs.h~inode-diet-move-i_cdev-into-a-union
+++ a/include/linux/fs.h
@@ -527,8 +527,8 @@ struct inode {
 	union {
 		struct pipe_inode_info	*i_pipe;
 		struct block_device	*i_bdev;
+		struct cdev		*i_cdev;
 	};
-	struct cdev		*i_cdev;
 	int			i_cindex;
 
 	__u32			i_generation;
_