[sheepdog] [PATCH 4/4] sheep: handle node leave event for updating inode object shared state

[Hitoshi Mitake]

When a node leaves from sheepdog cluster, it should be removed from a
list of participants of shared VDI.

Signed-off-by: Hitoshi Mitake <mitake.hitoshi at lab.ntt.co.jp>
---
 sheep/group.c      |  2 ++
 sheep/sheep_priv.h |  1 +
 sheep/vdi.c        | 23 +++++++++++++++++++----
 3 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/sheep/group.c b/sheep/group.c
index 39309eb..cdd44d4 100644
--- a/sheep/group.c
+++ b/sheep/group.c
@@ -1159,6 +1159,8 @@ main_fn void sd_leave_handler(const struct sd_node *left,
 	put_vnode_info(old_vnode_info);
 
 	sockfd_cache_del_node(&left->nid);
+
+	remove_node_from_participants(&left->nid);
 }
 
 static void update_node_size(struct sd_node *node)
diff --git a/sheep/sheep_priv.h b/sheep/sheep_priv.h
index 94a3a4f..26465ab 100644
--- a/sheep/sheep_priv.h
+++ b/sheep/sheep_priv.h
@@ -352,6 +352,7 @@ void validate_myself(uint32_t vid);
 void invalidate_other_nodes(uint32_t vid);
 int inode_coherence_update(uint32_t vid, bool validate,
 			   const struct node_id *sender);
+void remove_node_from_participants(const struct node_id *left);
 
 extern int ec_max_data_strip;
 
diff --git a/sheep/vdi.c b/sheep/vdi.c
index b8212d9..8872f91 100644
--- a/sheep/vdi.c
+++ b/sheep/vdi.c
@@ -386,7 +386,7 @@ static bool add_new_participant(struct vdi_state_entry *entry,
 }
 
 static void del_participant(struct vdi_state_entry *entry,
-			    const struct node_id *owner)
+			    const struct node_id *owner, bool err_msg)
 {
 	int idx = -1;
 
@@ -400,7 +400,10 @@ static void del_participant(struct vdi_state_entry *entry,
 	}
 
 	if (idx == -1) {
-		sd_err("unknown participants: %s", node_id_to_str(owner));
+		if (err_msg)
+			sd_err("unknown participants: %s",
+			       node_id_to_str(owner));
+
 		return;
 	}
 
@@ -515,7 +518,7 @@ bool vdi_unlock(uint32_t vid, const struct node_id *owner, int type)
 			sd_alert("leaving from unlocked VDI: %"PRIx32, vid);
 			break;
 		case LOCK_STATE_SHARED:
-			del_participant(entry, owner);
+			del_participant(entry, owner, true);
 			ret = true;
 			break;
 		case LOCK_STATE_LOCKED:
@@ -572,7 +575,7 @@ static void apply_vdi_lock_state_shared(uint32_t vid, bool lock,
 	if (lock)
 		add_new_participant(entry, locker);
 	else
-		del_participant(entry, locker);
+		del_participant(entry, locker, true);
 
 out:
 	sd_rw_unlock(&vdi_state_lock);
@@ -813,6 +816,18 @@ main_fn int inode_coherence_update(uint32_t vid, bool validate,
 	return SD_RES_SUCCESS;
 }
 
+main_fn void remove_node_from_participants(const struct node_id *left)
+{
+	struct vdi_state_entry *entry;
+
+	sd_write_lock(&vdi_state_lock);
+	rb_for_each_entry(entry, &vdi_state_root, node) {
+		del_participant(entry, left, false);
+	}
+	sd_rw_unlock(&vdi_state_lock);
+
+}
+
 static struct sd_inode *alloc_inode(const struct vdi_iocb *iocb,
 				    uint32_t new_snapid, uint32_t new_vid,
 				    uint32_t *data_vdi_id,
-- 
1.8.3.2