| From a56d1dc4042f6e4535dd93d64c8d9a9f85384db1 Mon Sep 17 00:00:00 2001 |
| From: Jan Kara <jack@suse.cz> |
| Date: Mon, 3 Sep 2012 16:50:42 +0200 |
| Subject: [PATCH] ext3: Fix fdatasync() for files with only i_size changes |
| |
| commit 156bddd8e505b295540f3ca0e27dda68cb0d49aa upstream. |
| |
| Code tracking when transaction needs to be committed on fdatasync(2) forgets |
| to handle a situation when only inode's i_size is changed. Thus in such |
| situations fdatasync(2) doesn't force transaction with new i_size to disk |
| and that can result in wrong i_size after a crash. |
| |
| Fix the issue by updating inode's i_datasync_tid whenever its size is |
| updated. |
| |
| Reported-by: Kristian Nielsen <knielsen@knielsen-hq.org> |
| Signed-off-by: Jan Kara <jack@suse.cz> |
| Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> |
| --- |
| fs/ext3/inode.c | 17 ++++++++++++++--- |
| 1 file changed, 14 insertions(+), 3 deletions(-) |
| |
| diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c |
| index ea33bdf0a300..f841730b751e 100644 |
| --- a/fs/ext3/inode.c |
| +++ b/fs/ext3/inode.c |
| @@ -2959,6 +2959,8 @@ static int ext3_do_update_inode(handle_t *handle, |
| struct ext3_inode_info *ei = EXT3_I(inode); |
| struct buffer_head *bh = iloc->bh; |
| int err = 0, rc, block; |
| + int need_datasync = 0; |
| + __le32 disksize; |
| |
| again: |
| /* we can't allow multiple procs in here at once, its a bit racey */ |
| @@ -2996,7 +2998,11 @@ again: |
| raw_inode->i_gid_high = 0; |
| } |
| raw_inode->i_links_count = cpu_to_le16(inode->i_nlink); |
| - raw_inode->i_size = cpu_to_le32(ei->i_disksize); |
| + disksize = cpu_to_le32(ei->i_disksize); |
| + if (disksize != raw_inode->i_size) { |
| + need_datasync = 1; |
| + raw_inode->i_size = disksize; |
| + } |
| raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec); |
| raw_inode->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); |
| raw_inode->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); |
| @@ -3012,8 +3018,11 @@ again: |
| if (!S_ISREG(inode->i_mode)) { |
| raw_inode->i_dir_acl = cpu_to_le32(ei->i_dir_acl); |
| } else { |
| - raw_inode->i_size_high = |
| - cpu_to_le32(ei->i_disksize >> 32); |
| + disksize = cpu_to_le32(ei->i_disksize >> 32); |
| + if (disksize != raw_inode->i_size_high) { |
| + raw_inode->i_size_high = disksize; |
| + need_datasync = 1; |
| + } |
| if (ei->i_disksize > 0x7fffffffULL) { |
| struct super_block *sb = inode->i_sb; |
| if (!EXT3_HAS_RO_COMPAT_FEATURE(sb, |
| @@ -3066,6 +3075,8 @@ again: |
| ext3_clear_inode_state(inode, EXT3_STATE_NEW); |
| |
| atomic_set(&ei->i_sync_tid, handle->h_transaction->t_tid); |
| + if (need_datasync) |
| + atomic_set(&ei->i_datasync_tid, handle->h_transaction->t_tid); |
| out_brelse: |
| brelse (bh); |
| ext3_std_error(inode->i_sb, err); |
| -- |
| 1.8.5.2 |
| |