[PATCH] ufs: truncate should allocate block for last byte

This patch fixes buggy behaviour of UFS
in such kind of scenario:
open(, O_TRUNC...)
ftruncate(, 1024)
ftruncate(, 0)

Such a scenario causes ufs_panic and remount read-only.  This happen
because of according to specification UFS should always allocate block for
last byte, and many parts of our implementation rely on this, but
`ufs_truncate' doesn't care about this.

To make possible return error code and to know about old size, this patch
removes `truncate' from ufs inode_operations and uses `setattr' method to
call ufs_truncate.

Signed-off-by: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/ufs_fs.h b/include/linux/ufs_fs.h
index e39b7cc..fc62887 100644
--- a/include/linux/ufs_fs.h
+++ b/include/linux/ufs_fs.h
@@ -993,7 +993,7 @@
 extern struct inode_operations ufs_fast_symlink_inode_operations;
 
 /* truncate.c */
-extern void ufs_truncate (struct inode *);
+extern int ufs_truncate (struct inode *, loff_t);
 
 static inline struct ufs_sb_info *UFS_SB(struct super_block *sb)
 {