md-cluster: Use a small window for resync

Suspending the entire device for resync could take too long. Resync
in small chunks.

cluster's resync window (32M) is maintained in r1conf as
cluster_sync_low and cluster_sync_high and processed in
raid1's sync_request(). If the current resync is outside the cluster
resync window:

1. Set the cluster_sync_low to curr_resync_completed.
2. Check if the sync will fit in the new window, if not issue a
   wait_barrier() and set cluster_sync_low to sector_nr.
3. Set cluster_sync_high to cluster_sync_low + resync_window.
4. Send a message to all nodes so they may add it in their suspension
   list.

bitmap_cond_end_sync is modified to allow to force a sync inorder
to get the curr_resync_completed uptodate with the sector passed.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 5 insertions, 36 deletions

diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 4a965f22be20..b94a2e68ef43 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -802,15 +802,6 @@ static int slot_number(struct mddev *mddev)
 	return cinfo->slot_number - 1;
 }
 
-static void resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
-{
-	struct md_cluster_info *cinfo = mddev->cluster_info;
-
-	add_resync_info(mddev, cinfo->bitmap_lockres, lo, hi);
-	/* Re-acquire the lock to refresh LVB */
-	dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW);
-}
-
 static int metadata_update_start(struct mddev *mddev)
 {
 	return lock_comm(mddev->cluster_info);
@@ -836,45 +827,25 @@ static int metadata_update_cancel(struct mddev *mddev)
 	return dlm_unlock_sync(cinfo->token_lockres);
 }
 
-static int resync_send(struct mddev *mddev, enum msg_type type,
-		sector_t lo, sector_t hi)
+static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
 {
 	struct md_cluster_info *cinfo = mddev->cluster_info;
 	struct cluster_msg cmsg;
 	int slot = cinfo->slot_number - 1;
 
+	add_resync_info(mddev, cinfo->bitmap_lockres, lo, hi);
+	/* Re-acquire the lock to refresh LVB */
+	dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW);
 	pr_info("%s:%d lo: %llu hi: %llu\n", __func__, __LINE__,
 			(unsigned long long)lo,
 			(unsigned long long)hi);
-	resync_info_update(mddev, lo, hi);
-	cmsg.type = cpu_to_le32(type);
+	cmsg.type = cpu_to_le32(RESYNCING);
 	cmsg.slot = cpu_to_le32(slot);
 	cmsg.low = cpu_to_le64(lo);
 	cmsg.high = cpu_to_le64(hi);
 	return sendmsg(cinfo, &cmsg);
 }
 
-static int resync_start(struct mddev *mddev, sector_t lo, sector_t hi)
-{
-	pr_info("%s:%d\n", __func__, __LINE__);
-	return resync_send(mddev, RESYNCING, lo, hi);
-}
-
-static void resync_finish(struct mddev *mddev)
-{
-	struct md_cluster_info *cinfo = mddev->cluster_info;
-	struct cluster_msg cmsg;
-	int slot = cinfo->slot_number - 1;
-
-	pr_info("%s:%d\n", __func__, __LINE__);
-	resync_send(mddev, RESYNCING, 0, 0);
-	if (test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
-		cmsg.type = cpu_to_le32(BITMAP_NEEDS_SYNC);
-		cmsg.slot = cpu_to_le32(slot);
-		sendmsg(cinfo, &cmsg);
-	}
-}
-
 static int area_resyncing(struct mddev *mddev, int direction,
 		sector_t lo, sector_t hi)
 {
@@ -997,8 +968,6 @@ static struct md_cluster_operations cluster_ops = {
 	.leave  = leave,
 	.slot_number = slot_number,
 	.resync_info_update = resync_info_update,
-	.resync_start = resync_start,
-	.resync_finish = resync_finish,
 	.metadata_update_start = metadata_update_start,
 	.metadata_update_finish = metadata_update_finish,
 	.metadata_update_cancel = metadata_update_cancel,