From aaecbb25d185ff59c3f8538bf4f854bd14377025 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@infradead.org>
Date: Tue, 19 Nov 2013 07:17:07 -0800
Subject: fs: fix iversion handling

commit dff6efc326a4d5f305797d4a6bba14f374fdd633 upstream.

Currently notify_change directly updates i_version for size updates,
which not only is counter to how all other fields are updated through
struct iattr, but also breaks XFS, which need inode updates to happen
under its own lock, and synchronized to the structure that gets written
to the log.

Remove the update in the common code, and it to btrfs and ext4,
XFS already does a proper updaste internally and currently gets a
double update with the existing code.

IMHO this is 3.13 and -stable material and should go in through the XFS
tree.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Acked-by: Jan Kara <jack@suse.cz>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

diff --git a/fs/attr.c b/fs/attr.c
index 1449adb..8dd5825 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -182,11 +182,6 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
 			return -EPERM;
 	}
 
-	if ((ia_valid & ATTR_SIZE) && IS_I_VERSION(inode)) {
-		if (attr->ia_size != inode->i_size)
-			inode_inc_iversion(inode);
-	}
-
 	if ((ia_valid & ATTR_MODE)) {
 		umode_t amode = attr->ia_mode;
 		/* Flag setting protected by i_mutex */
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 1b63d29..3d03d2e 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4354,8 +4354,12 @@ static int btrfs_setsize(struct inode *inode, struct iattr *attr)
 	 * these flags set.  For all other operations the VFS set these flags
 	 * explicitly if it wants a timestamp update.
 	 */
-	if (newsize != oldsize && (!(mask & (ATTR_CTIME | ATTR_MTIME))))
-		inode->i_ctime = inode->i_mtime = current_fs_time(inode->i_sb);
+	if (newsize != oldsize) {
+		inode_inc_iversion(inode);
+		if (!(mask & (ATTR_CTIME | ATTR_MTIME)))
+			inode->i_ctime = inode->i_mtime =
+				current_fs_time(inode->i_sb);
+	}
 
 	if (newsize > oldsize) {
 		truncate_pagecache(inode, newsize);
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 1ddee3d..55fe412 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4582,6 +4582,10 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 			if (attr->ia_size > sbi->s_bitmap_maxbytes)
 				return -EFBIG;
 		}
+
+		if (IS_I_VERSION(inode) && attr->ia_size != inode->i_size)
+			inode_inc_iversion(inode);
+
 		if (S_ISREG(inode->i_mode) &&
 		    (attr->ia_size < inode->i_size)) {
 			if (ext4_should_order_data(inode)) {
-- 
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