| Message ID | 20120614001531.GB22646@thunk.org |
|---|---|
| State | Accepted, archived |
| Headers | show |
On Wed, Jun 13, 2012 at 08:15:31PM -0400, Ted Ts'o wrote: > Hi Zheng, > > I finally got around to reviewing this patch and I had one comment > > > Ext4 must make sure the transaction to be commited to the disk when > > user opens a file with O_(D)SYNC flag and do a fallocate(2) call. > > > > diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c > > index 74f23c2..00e32d9 100644 > > --- a/fs/ext4/extents.c > > +++ b/fs/ext4/extents.c > > @@ -4356,6 +4356,8 @@ retry: > > ret = PTR_ERR(handle); > > break; > > } > > + if (file->f_flags & O_SYNC) > > + ext4_handle_sync(handle); > > ret = ext4_map_blocks(handle, inode, &map, flags); > > if (ret <= 0) { > > #ifdef EXT4FS_DEBUG > > For a large fallocate(), it can require multiple calls to > ext4_map_blocks(), and we should only sync after we've allocated the > last segment. We should also not force a sync if there is an error > allocating blocks. So it seems to me this patch would be better; what > do you think? Hi Ted, Thank you for your review. I agree with you that the following patch is better. Regards, Zheng > commit b790d70be9515dfaba59b0be0aff373e6867826d > Author: Zheng Liu <gnehzuil.liu@gmail.com> > Date: Wed Jun 13 20:15:01 2012 -0400 > > ext4: honor O_(D)SYNC semantic in ext4_fallocate() > > Ext4 must make sure the transaction to be commited to the disk when > user opens a file with O_(D)SYNC flag and do a fallocate(2) call. > > This problem had been reported by Christoph Hellwig in this thread: > http://www.spinics.net/lists/linux-btrfs/msg13621.html > > Reported-by: Christoph Hellwig <hch@infradead.org> > Signed-off-by: Zheng Liu <wenqing.lz@taobao.com> > Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> > > diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c > index 91341ec..f1089cb 100644 > --- a/fs/ext4/extents.c > +++ b/fs/ext4/extents.c > @@ -4420,6 +4420,8 @@ retry: > ext4_falloc_update_inode(inode, mode, new_size, > (map.m_flags & EXT4_MAP_NEW)); > ext4_mark_inode_dirty(handle, inode); > + if ((file->f_flags & O_SYNC) && ret >= max_blocks) > + ext4_handle_sync(handle); > ret2 = ext4_journal_stop(handle); > if (ret2) > break; -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 91341ec..f1089cb 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -4420,6 +4420,8 @@ retry: ext4_falloc_update_inode(inode, mode, new_size, (map.m_flags & EXT4_MAP_NEW)); ext4_mark_inode_dirty(handle, inode); + if ((file->f_flags & O_SYNC) && ret >= max_blocks) + ext4_handle_sync(handle); ret2 = ext4_journal_stop(handle); if (ret2) break;