lvmlockd: zero extended lvmlock LV

After the internal lvmlock LV (holding sanlock leases) is
extended to hold more leases, it needs to be zeroed.
sanlock expects to see either zeroed blocks or blocks
initialized with leases.

1 files changed, 41 insertions, 1 deletions

diff --git a/lib/locking/lvmlockd.c b/lib/locking/lvmlockd.c
index 54e3cf6ea..d85021cc6 100644
--- a/lib/locking/lvmlockd.c
+++ b/lib/locking/lvmlockd.c
@@ -365,6 +365,9 @@ static int _remove_sanlock_lv(struct cmd_context *cmd, struct volume_group *vg)
 
 static int _extend_sanlock_lv(struct cmd_context *cmd, struct volume_group *vg, int extend_mb)
 {
+	struct device *dev;
+	char path[PATH_MAX];
+	uint64_t old_size_bytes, new_size_bytes;
 	struct logical_volume *lv = vg->sanlock_lv;
 	struct lvresize_params lp = {
 		.sign = SIGN_NONE,
@@ -374,12 +377,49 @@ static int _extend_sanlock_lv(struct cmd_context *cmd, struct volume_group *vg,
 		.force = 1,
 	};
 
+	old_size_bytes = lv->size * SECTOR_SIZE;
+
 	if (!lv_resize(lv, &lp, &vg->pvs)) {
-		log_error("Extend LV %s to size %s failed.",
+		log_error("Extend sanlock LV %s to size %s failed.",
 			  display_lvname(lv), display_size(cmd, lp.size));
 		return 0;
 	}
 
+	new_size_bytes = lv->size * SECTOR_SIZE;
+
+	if (dm_snprintf(path, sizeof(path), "%s/mapper/%s-%s", lv->vg->cmd->dev_dir,
+			lv->vg->name, lv->name) < 0) {
+		log_error("Extend sanlock LV %s name too long - extended size not zeroed.",
+			  display_lvname(lv));
+		return 0;
+	}
+
+	log_debug("Extend sanlock LV zeroing blocks from offset " FMTu64 " bytes len %u bytes",
+		  old_size_bytes, (uint32_t)(new_size_bytes - old_size_bytes));
+
+	log_print("Zeroing %u MiB on extended internal lvmlock LV...", extend_mb);
+
+	if (!(dev = dev_cache_get(path, NULL))) {
+		log_error("Extend sanlock LV %s cannot find device.", display_lvname(lv));
+		return 0;
+	}
+
+	if (!dev_open_quiet(dev)) {
+		log_error("Extend sanlock LV %s cannot open device.", display_lvname(lv));
+		return 0;
+	}
+
+	if (!dev_set(dev, old_size_bytes, new_size_bytes - old_size_bytes, 0)) {
+		log_error("Extend sanlock LV %s cannot zero device.", display_lvname(lv));
+		dev_close_immediate(dev);
+		return 0;
+	}
+
+	dev_flush(dev);
+
+	if (!dev_close_immediate(dev))
+		stack;
+
 	return 1;
 }