[PATCH] fsstack: Introduce fsstack_copy_{attr,inode}_*

Introduce several fsstack_copy_* functions which allow stackable filesystems
(such as eCryptfs and Unionfs) to easily copy over (currently only) inode
attributes.  This prevents code duplication and allows for code reuse.

[akpm@osdl.org: Remove unneeded wrapper]
[bunk@stusta.de: fs/stack.c should #include <linux/fs_stack.h>]
Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 31 insertions, 0 deletions

diff --git a/include/linux/fs_stack.h b/include/linux/fs_stack.h
new file mode 100644
index 000000000000..bb516ceeefc9
--- /dev/null
+++ b/include/linux/fs_stack.h
@@ -0,0 +1,31 @@
+#ifndef _LINUX_FS_STACK_H
+#define _LINUX_FS_STACK_H
+
+/* This file defines generic functions used primarily by stackable
+ * filesystems; none of these functions require i_mutex to be held.
+ */
+
+#include <linux/fs.h>
+
+/* externs for fs/stack.c */
+extern void fsstack_copy_attr_all(struct inode *dest, const struct inode *src,
+                                int (*get_nlinks)(struct inode *));
+
+extern void fsstack_copy_inode_size(struct inode *dst, const struct inode *src);
+
+/* inlines */
+static inline void fsstack_copy_attr_atime(struct inode *dest,
+                                           const struct inode *src)
+{
+        dest->i_atime = src->i_atime;
+}
+
+static inline void fsstack_copy_attr_times(struct inode *dest,
+                                           const struct inode *src)
+{
+        dest->i_atime = src->i_atime;
+        dest->i_mtime = src->i_mtime;
+        dest->i_ctime = src->i_ctime;
+}
+
+#endif /* _LINUX_FS_STACK_H */