[PATCH 3.16 138/328] ubifs: Fix synced_i_size calculation for xattr inodes

[Ben Hutchings]

3.16.62-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Richard Weinberger <richard@xxxxxx>

commit 59965593205fa4044850d35ee3557cf0b7edcd14 upstream.

In ubifs_jnl_update() we sync parent and child inodes to the flash,
in case of xattrs, the parent inode (AKA host inode) has a non-zero
data_len. Therefore we need to adjust synced_i_size too.

This issue was reported by ubifs self tests unter a xattr related work
load.
UBIFS error (ubi0:0 pid 1896): dbg_check_synced_i_size: ui_size is 4, synced_i_size is 0, but inode is clean
UBIFS error (ubi0:0 pid 1896): dbg_check_synced_i_size: i_ino 65, i_mode 0x81a4, i_size 4

Fixes: 1e51764a3c2a ("UBIFS: add new flash file system")
Signed-off-by: Richard Weinberger <richard@xxxxxx>
[bwh: Backported to 3.16: s/host_ui/dir_ui/]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 fs/ubifs/journal.c | 5 +++++
 1 file changed, 5 insertions(+)

--- a/fs/ubifs/journal.c
+++ b/fs/ubifs/journal.c
@@ -657,6 +657,11 @@ int ubifs_jnl_update(struct ubifs_info *
 	spin_lock(&ui->ui_lock);
 	ui->synced_i_size = ui->ui_size;
 	spin_unlock(&ui->ui_lock);
+	if (xent) {
+		spin_lock(&dir_ui->ui_lock);
+		dir_ui->synced_i_size = dir_ui->ui_size;
+		spin_unlock(&dir_ui->ui_lock);
+	}
 	mark_inode_clean(c, ui);
 	mark_inode_clean(c, dir_ui);
 	return 0;