ext3: copy i_flags to inode flags on write

A patch that stores inode flags such as S_IMMUTABLE, S_APPEND, etc.  from
i_flags to EXT3_I(inode)->i_flags when inode is written to disk.  The same
thing is done on GETFLAGS ioctl.

Quota code changes these flags on quota files (to make it harder for
sysadmin to screw himself) and these changes were not correctly propagated
into the filesystem (especially, lsattr did not show them and users were
wondering...).

Propagate flags such as S_APPEND, S_IMMUTABLE, etc.  from i_flags into
ext3-specific i_flags.  Hence, when someone sets these flags via a
different interface than ioctl, they are stored correctly.

Signed-off-by: Jan Kara <jack@suse.cz>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index f9bcddb..e1bb031 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -2580,6 +2580,25 @@
 		inode->i_flags |= S_DIRSYNC;
 }
 
+/* Propagate flags from i_flags to EXT3_I(inode)->i_flags */
+void ext3_get_inode_flags(struct ext3_inode_info *ei)
+{
+	unsigned int flags = ei->vfs_inode.i_flags;
+
+	ei->i_flags &= ~(EXT3_SYNC_FL|EXT3_APPEND_FL|
+			EXT3_IMMUTABLE_FL|EXT3_NOATIME_FL|EXT3_DIRSYNC_FL);
+	if (flags & S_SYNC)
+		ei->i_flags |= EXT3_SYNC_FL;
+	if (flags & S_APPEND)
+		ei->i_flags |= EXT3_APPEND_FL;
+	if (flags & S_IMMUTABLE)
+		ei->i_flags |= EXT3_IMMUTABLE_FL;
+	if (flags & S_NOATIME)
+		ei->i_flags |= EXT3_NOATIME_FL;
+	if (flags & S_DIRSYNC)
+		ei->i_flags |= EXT3_DIRSYNC_FL;
+}
+
 void ext3_read_inode(struct inode * inode)
 {
 	struct ext3_iloc iloc;
@@ -2735,6 +2754,7 @@
 	if (ei->i_state & EXT3_STATE_NEW)
 		memset(raw_inode, 0, EXT3_SB(inode->i_sb)->s_inode_size);
 
+	ext3_get_inode_flags(ei);
 	raw_inode->i_mode = cpu_to_le16(inode->i_mode);
 	if(!(test_opt(inode->i_sb, NO_UID32))) {
 		raw_inode->i_uid_low = cpu_to_le16(low_16_bits(inode->i_uid));