From mboxrd@z Thu Jan 1 00:00:00 1970 From: TaoMa Date: Tue, 02 Feb 2010 06:13:38 +0800 Subject: [Ocfs2-devel] [PATCH 2/2] Ocfs2: Fix punching hole codes to correctly do CoW during cluster zeroing. In-Reply-To: <1265020173-14623-2-git-send-email-tristan.ye@oracle.com> References: <1265020173-14623-1-git-send-email-tristan.ye@oracle.com> <1265020173-14623-2-git-send-email-tristan.ye@oracle.com> Message-ID: <4B675212.7080706@oracle.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com Hi Tristan, Tristan Ye wrote: > Based on the former patch of truncating optimization, bugfix for refcount on > punching holes can be fairly easy and straightforward since most of work we > should take into account for refcounting have been completed already in func > ocfs2_remove_btree_range(), which is also being used by our truncating codes. > > The patch just did CoW for reflinks when a hole is being punched whose start > and end offset were within one cluster, which means partial zeroing for a cluster > will be performed soon. > > The patch has been tested fixing the following bug: > > http://oss.oracle.com/bugzilla/show_bug.cgi?id=1216 > > Signed-off-by: Tristan Ye > --- > fs/ocfs2/file.c | 21 +++++++++++++++++++++ > 1 files changed, 21 insertions(+), 0 deletions(-) > > diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c > index e0c9d1c..bb15a1e 100644 > --- a/fs/ocfs2/file.c > +++ b/fs/ocfs2/file.c > @@ -1458,6 +1458,27 @@ static int ocfs2_remove_inode_range(struct inode *inode, > goto out; > } > > + /* > + * For reflinks, we may need to CoW 2 clusters which might be > + * partially zero'd later, if hole's start and end offset were > + * within one cluster(means is not exactly aligned to clustersize). > + */ > + > + if (OCFS2_I(inode)->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL) { > + > + ret = ocfs2_cow_file_pos(inode, di_bh, byte_start); > + if (ret) { > + mlog_errno(ret); > + goto out; > + } > + > + ret = ocfs2_cow_file_pos(inode, di_bh, byte_start + byte_len); > + if (ret) { > + mlog_errno(ret); > + goto out; > + } > + } > + > If the bytes_start and bytes_sart + byte_len are in alignment with cluster size, we don't need to do CoW. Regards, Tao