[Ocfs2-devel] [PATCH 6/6] Use the new DLM operation callbacks while requesting new lockspace

[Goldwyn Rodrigues <rgoldwyn@suse.de>]

On 11/03/2013 07:12 PM, Mark Fasheh wrote:
> On Fri, Oct 18, 2013 at 09:46:31AM -0500, Goldwyn Rodrigues wrote:
>> Attempt to use the new DLM operations. If it is not supported,
>> use the traditional ocfs2_controld.
>>
>> To exchange ocfs2 versioning, we use the LVB of the version dlm lock.
>> It first attempts to take the lock in EX mode (non-blocking). If
>> successful (which means it is the first mount), it writes the
>> version number and downconverts to PR lock. If it is unsuccessful,
>> it reads the version from the lock.
>>
>> If this becomes the standard (wit o2cb as well), it could
>> simplify userspace tools to check if the filesystem is mounted
>> on other nodes.
>>
>> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
>> ---
>>   fs/ocfs2/stack_user.c | 97 ++++++++++++++++++++++++++++++++++++++-------------
>>   1 file changed, 73 insertions(+), 24 deletions(-)
>
>
>> @@ -948,12 +961,65 @@ static int user_cluster_connect(struct ocfs2_cluster_connection *conn)
>>   		goto out;
>>   	}
>>
>> -	lc->oc_type = WITH_CONTROLD;
>> +	init_waitqueue_head(&lc->oc_wait);
>> +	init_completion(&lc->oc_sync_wait);
>> +	atomic_set(&lc->oc_this_node, 0);
>> +	conn->cc_private = lc;
>> +	lc->oc_type = NO_CONTROLD;
>> +
>> +	rc = dlm_new_lockspace(conn->cc_name, conn->cc_cluster_name,
>> +			       DLM_LSFL_FS, DLM_LVB_LEN,
>> +			       &ocfs2_ls_ops, conn, &ops_rv, &fsdlm);
>> +	if (rc)
>> +		goto out;
>> +
>> +	if (ops_rv == -EOPNOTSUPP) {
>> +		lc->oc_type = WITH_CONTROLD;
>> +		printk(KERN_NOTICE "ocfs2: You seem to be using an older "
>> +				"version of dlm_controld and/or ocfs2-tools."
>> +				" Please consider upgrading.\n");
>> +	} else if (ops_rv) {
>> +		rc = ops_rv;
>> +		goto out;
>> +	}
>> +	conn->cc_lockspace = fsdlm;
>>
>>   	rc = ocfs2_live_connection_new(conn, lc);
>>   	if (rc)
>>   		goto out;
>>
>> +	if (lc->oc_type == NO_CONTROLD) {
>> +		int ret;
>> +		lc->oc_version_lksb.sb_lvbptr = lc->oc_lvb;
>> +		ret = version_lock(conn, DLM_LOCK_EX,
>> +				DLM_LKF_VALBLK|DLM_LKF_NOQUEUE);
>> +		running_proto.pv_major =
>> +			ocfs2_user_plugin.sp_max_proto.pv_major;
>> +		running_proto.pv_minor =
>> +			ocfs2_user_plugin.sp_max_proto.pv_minor;
>> +		if (!ret) {
>> +			conn->cc_version.pv_major = running_proto.pv_major;
>> +			conn->cc_version.pv_minor = running_proto.pv_minor;
>> +			version_to_lvb(&running_proto, lc->oc_lvb);
>> +			version_lock(conn, DLM_LOCK_PR, DLM_LKF_CONVERT|DLM_LKF_VALBLK);
>> +		} else if (ret == -EAGAIN) {
>> +			version_lock(conn, DLM_LOCK_PR, DLM_LKF_VALBLK);
>> +			ret = lvb_to_version(lc->oc_lvb, &conn->cc_version);
>> +			if (ret) {
>> +				rc = ret;
>> +				user_cluster_disconnect(conn);
>> +				goto out;
>> +			}
>> +		} else {
>> +			printk(KERN_ERR "ocfs2: Could not determine"
>> +					" locking version\n");
>> +			rc = ret;
>> +			user_cluster_disconnect(conn);
>> +			goto out;
>> +		}
>> +		wait_event(lc->oc_wait, (atomic_read(&lc->oc_this_node) > 0));
>> +	}
>> +
>
> Can we put this block in it's own function?

Yes. Sure.

I suppose thats about it. I will incorporate these changes and put them 
in the next series.


-- 
Goldwyn