From: Petr Rockai <prockai@redhat.com>
Date: Wed, 15 Feb 2012 14:06:48 +0000 (+0000)
Subject: In lvmetad, also nuke VGs when all their PVs are stolen by another VG (vgmerge
X-Git-Tag: v2_02_96~382
X-Git-Url: https://sourceware.org/git/?a=commitdiff_plain;h=23ce26fe224c674a59b964f70267ddfb9fd5785f;p=lvm2.git

In lvmetad, also nuke VGs when all their PVs are stolen by another VG (vgmerge
& vgsplit do this).
---

diff --git a/daemons/lvmetad/lvmetad-core.c b/daemons/lvmetad/lvmetad-core.c
index c0d692d19..e8524a45e 100644
--- a/daemons/lvmetad/lvmetad-core.c
+++ b/daemons/lvmetad/lvmetad-core.c
@@ -487,26 +487,45 @@ static int compare_config(struct dm_config_node *a, struct dm_config_node *b)
 	return result;
 }
 
+static int vg_remove_if_missing(lvmetad_state *s, const char *vgid);
+
 /* You need to be holding the pvid_to_vgid lock already to call this. */
-static int update_pvid_to_vgid(lvmetad_state *s, struct dm_config_tree *vg, const char *vgid)
+static int update_pvid_to_vgid(lvmetad_state *s, struct dm_config_tree *vg,
+			       const char *vgid, int nuke_empty)
 {
 	struct dm_config_node *pv = pvs(vg->root);
+	struct dm_hash_table *to_check = dm_hash_create(32);
 
 	if (!vgid)
 		return 0;
 
 	while (pv) {
 		const char *pvid = dm_config_find_str(pv->child, "id", NULL);
+		const char *vgid_old = dm_hash_lookup(s->pvid_to_vgid, pvid);
+		if (vgid_old && nuke_empty)
+			dm_hash_insert(to_check, vgid_old, (void*) 1);
 		dm_hash_insert(s->pvid_to_vgid, pvid, (void *) vgid);
 		debug("remap PV %s to VG %s\n", pvid, vgid);
 		pv = pv->sib;
 	}
 
+	struct dm_hash_node *n = dm_hash_get_first(to_check);
+
+	while (n) {
+		const char *check_vgid = dm_hash_get_key(to_check, n);
+		lock_vg(s, check_vgid);
+		vg_remove_if_missing(s, check_vgid);
+		unlock_vg(s, check_vgid);
+		n = dm_hash_get_next(to_check, n);
+	}
+
+	dm_hash_destroy(to_check);
+
 	return 1;
 }
 
-/* A pvid map lock needs to be held. */
-static int remove_metadata(lvmetad_state *s, const char *vgid)
+/* A pvid map lock needs to be held if update_pvids = 1. */
+static int remove_metadata(lvmetad_state *s, const char *vgid, int update_pvids)
 {
 	struct dm_config_tree *old;
 	const char *oldname;
@@ -518,7 +537,8 @@ static int remove_metadata(lvmetad_state *s, const char *vgid)
 	if (!old)
 		return 0;
 
-	update_pvid_to_vgid(s, old, "#orphan");
+	if (update_pvids)
+		update_pvid_to_vgid(s, old, "#orphan", 0);
 	/* need to update what we have since we found a newer version */
 	dm_hash_remove(s->vgid_to_metadata, vgid);
 	dm_hash_remove(s->vgid_to_vgname, vgid);
@@ -554,7 +574,7 @@ static int vg_remove_if_missing(lvmetad_state *s, const char *vgid)
 
 	if (missing) {
 		debug("nuking VG %s\n", vgid);
-		remove_metadata(s, vgid);
+		remove_metadata(s, vgid, 0);
 	}
 
 	unlock_pvid_to_status(s);
@@ -629,7 +649,7 @@ static int update_metadata(lvmetad_state *s, const char *name, const char *_vgid
 	if (haveseq >= 0 && haveseq < seq) {
 		debug("Updating metadata for %s at %d to %d\n", _vgid, haveseq, seq);
 		/* temporarily orphan all of our PVs */
-		remove_metadata(s, vgid);
+		remove_metadata(s, vgid, 1);
 	}
 
 	// debug_cft("METADATA", metadata);
@@ -640,7 +660,7 @@ static int update_metadata(lvmetad_state *s, const char *name, const char *_vgid
 	dm_hash_insert(s->vgname_to_vgid, name, (void *)vgid);
 	unlock_vgid_to_metadata(s);
 
-	update_pvid_to_vgid(s, cft, vgid);
+	update_pvid_to_vgid(s, cft, vgid, 1);
 
 	unlock_pvid_to_vgid(s);
 	retval = 1;
@@ -773,7 +793,7 @@ static response vg_remove(lvmetad_state *s, request r)
 	fprintf(stderr, "vg_remove: %s\n", vgid);
 
 	lock_pvid_to_vgid(s);
-	remove_metadata(s, vgid);
+	remove_metadata(s, vgid, 1);
 	unlock_pvid_to_vgid(s);
 
 	return daemon_reply_simple("OK", NULL);