[PATCH 2/4] md-cluster: remove capabilities

[Goldwyn Rodrigues <rgoldwyn@suse.de>]

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
---
 drivers/md/md-cluster.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 drivers/md/md-cluster.h |  1 +
 drivers/md/md.c         | 24 +++++++++++++++---------
 drivers/md/md.h         |  1 +
 4 files changed, 64 insertions(+), 9 deletions(-)

diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 96679b2..d036c83 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -72,6 +72,7 @@ enum msg_type {
 	METADATA_UPDATED = 0,
 	RESYNCING,
 	NEWDISK,
+	REMOVE,
 };
 
 struct cluster_msg {
@@ -186,6 +187,20 @@ static char *pretty_uuid(char *dest, char *src)
 	return dest;
 }
 
+static struct md_rdev *find_rdev_uuid(struct mddev *mddev, char *uuid)
+{
+	struct md_rdev *rdev;
+	struct mdp_superblock_1 *sb;
+
+	rdev_for_each_rcu(rdev, mddev) {
+		sb = page_address(rdev->sb_page);
+		if (!strncmp(uuid, sb->device_uuid, 16)) {
+			return rdev;
+		}
+	}
+	return NULL;
+}
+
 static void add_resync_info(struct mddev *mddev, struct dlm_lock_resource *lockres,
 		sector_t lo, sector_t hi)
 {
@@ -401,6 +416,17 @@ static void process_metadata_update(struct mddev *mddev, struct cluster_msg *msg
 	dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
 }
 
+static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
+{
+	struct md_rdev *rdev = find_rdev_uuid(mddev, msg->uuid);
+	char uuid[32];
+
+	if (rdev)
+		md_kick_rdev_from_array(rdev);
+	else
+		pr_warn("%s: %d Could not find disk with uuid: %s", __func__, __LINE__, pretty_uuid(uuid, msg->uuid));
+}
+
 static void process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
 {
 	switch (msg->type) {
@@ -419,6 +445,15 @@ static void process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
 		pr_info("%s: %d Received message: NEWDISK from %d\n",
 			__func__, __LINE__, msg->slot);
 		process_add_new_disk(mddev, msg);
+		break;
+	case REMOVE:
+		pr_info("%s: %d Received REMOVE from %d\n",
+			__func__, __LINE__, msg->slot);
+		process_remove_disk(mddev, msg);
+		break;
+	default:
+		pr_warn("%s:%d Received unknown message from %d\n",
+			__func__, __LINE__, msg->slot);
 	};
 }
 
@@ -854,6 +889,17 @@ static int new_disk_ack(struct mddev *mddev, bool ack)
 	return 0;
 }
 
+static int remove_disk(struct mddev *mddev, struct md_rdev *rdev)
+{
+	struct cluster_msg cmsg;
+	struct md_cluster_info *cinfo = mddev->cluster_info;
+	struct mdp_superblock_1 *sb = page_address(rdev->sb_page);
+	char *uuid = sb->device_uuid;
+	cmsg.type = REMOVE;
+	memcpy(cmsg.uuid, uuid, 16);
+	return __sendmsg(cinfo, &cmsg);
+}
+
 static struct md_cluster_operations cluster_ops = {
 	.join   = join,
 	.leave  = leave,
@@ -868,6 +914,7 @@ static struct md_cluster_operations cluster_ops = {
 	.add_new_disk_start = add_new_disk_start,
 	.add_new_disk_finish = add_new_disk_finish,
 	.new_disk_ack = new_disk_ack,
+	.remove_disk = remove_disk,
 };
 
 static int __init cluster_init(void)
diff --git a/drivers/md/md-cluster.h b/drivers/md/md-cluster.h
index 7417133..71e5143 100644
--- a/drivers/md/md-cluster.h
+++ b/drivers/md/md-cluster.h
@@ -22,6 +22,7 @@ struct md_cluster_operations {
 	int (*add_new_disk_start)(struct mddev *mddev, struct md_rdev *rdev);
 	int (*add_new_disk_finish)(struct mddev *mddev);
 	int (*new_disk_ack)(struct mddev *mddev, bool ack);
+	int (*remove_disk)(struct mddev *mddev, struct md_rdev *rdev);
 };
 
 #endif /* _MD_CLUSTER_H */
diff --git a/drivers/md/md.c b/drivers/md/md.c
index bc11551..0c65e51 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2291,11 +2291,12 @@ static void export_rdev(struct md_rdev * rdev)
 	kobject_put(&rdev->kobj);
 }
 
-static void kick_rdev_from_array(struct md_rdev * rdev)
+void md_kick_rdev_from_array(struct md_rdev * rdev)
 {
 	unbind_rdev_from_array(rdev);
 	export_rdev(rdev);
 }
+EXPORT_SYMBOL_GPL(md_kick_rdev_from_array);
 
 static void export_array(struct mddev *mddev)
 {
@@ -2306,7 +2307,7 @@ static void export_array(struct mddev *mddev)
 			MD_BUG();
 			continue;
 		}
-		kick_rdev_from_array(rdev);
+		md_kick_rdev_from_array(rdev);
 	}
 	if (!list_empty(&mddev->disks))
 		MD_BUG();
@@ -2750,9 +2751,11 @@ state_store(struct md_rdev *rdev, const char *buf, size_t len)
 			err = -EBUSY;
 		else {
 			struct mddev *mddev = rdev->mddev;
-			if (mddev_is_clustered(mddev))
+			if (mddev_is_clustered(mddev)) {
 				md_cluster_ops->metadata_update_start(mddev);
-			kick_rdev_from_array(rdev);
+				md_cluster_ops->remove_disk(mddev, rdev);
+			}
+			md_kick_rdev_from_array(rdev);
 			if (mddev->pers) {
 				set_bit(MD_CHANGE_DEVS, &mddev->flags);
 				md_wakeup_thread(mddev->thread);
@@ -3424,7 +3427,7 @@ static void analyze_sbs(struct mddev * mddev)
 				"md: fatal superblock inconsistency in %s"
 				" -- removing from array\n", 
 				bdevname(rdev->bdev,b));
-			kick_rdev_from_array(rdev);
+			md_kick_rdev_from_array(rdev);
 		}
 
 
@@ -3440,7 +3443,7 @@ static void analyze_sbs(struct mddev * mddev)
 			       "md: %s: %s: only %d devices permitted\n",
 			       mdname(mddev), bdevname(rdev->bdev, b),
 			       mddev->max_disks);
-			kick_rdev_from_array(rdev);
+			md_kick_rdev_from_array(rdev);
 			continue;
 		}
 		if (rdev != freshest) {
@@ -3449,7 +3452,7 @@ static void analyze_sbs(struct mddev * mddev)
 				printk(KERN_WARNING "md: kicking non-fresh %s"
 					" from array!\n",
 					bdevname(rdev->bdev,b));
-				kick_rdev_from_array(rdev);
+				md_kick_rdev_from_array(rdev);
 				continue;
 			}
 			/* No device should have a Candidate flag
@@ -3458,7 +3461,7 @@ static void analyze_sbs(struct mddev * mddev)
 			if (test_bit(Candidate, &rdev->flags)) {
 				pr_info("md: kicking Cluster Candidate %s from array!\n",
 					bdevname(rdev->bdev, b));
-				kick_rdev_from_array(rdev);
+				md_kick_rdev_from_array(rdev);
 			}
 		}
 		if (mddev->level == LEVEL_MULTIPATH) {
@@ -6083,7 +6086,10 @@ static int hot_remove_disk(struct mddev * mddev, dev_t dev)
 	if (rdev->raid_disk >= 0)
 		goto busy;
 
-	kick_rdev_from_array(rdev);
+	if (mddev_is_clustered(mddev))
+		md_cluster_ops->remove_disk(mddev, rdev);
+
+	md_kick_rdev_from_array(rdev);
 	set_bit(MD_CHANGE_DEVS, &mddev->flags);
 	if (mddev->thread)
 		md_wakeup_thread(mddev->thread);
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 29ab989..c6c0846 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -651,6 +651,7 @@ extern void md_trim_bio(struct bio *bio, int offset, int size);
 extern void md_unplug(struct blk_plug_cb *cb, bool from_schedule);
 extern void md_reload_sb(struct mddev *mddev);
 extern void md_update_sb(struct mddev *mddev, int force);
+extern void md_kick_rdev_from_array(struct md_rdev *rdev);
 
 static inline void rdev_dec_pending(struct md_rdev *rdev, struct mddev *mddev)
 {
-- 
2.1.4