pvscan: use new label_scan data

'pvscan --cache' for scanning all devices now uses
label_scan_async and can reuse data like other commands.

'pvscan --cache dev' can't do a label_scan because it's
only allowed to read the single dev.  A label_read on
that single dev is added prior to reading the VG from it.

7 files changed, 56 insertions, 17 deletions

diff --git a/lib/cache/lvmetad.c b/lib/cache/lvmetad.c
index 86a2caced..73243a6ba 100644
--- a/lib/cache/lvmetad.c
+++ b/lib/cache/lvmetad.c
@@ -1756,6 +1756,7 @@ int lvmetad_pv_gone_by_dev(struct device *dev)
  */
 
 struct _lvmetad_pvscan_baton {
+	struct cmd_context *cmd;
 	struct volume_group *vg;
 	struct format_instance *fid;
 };
@@ -1763,10 +1764,14 @@ struct _lvmetad_pvscan_baton {
 static int _lvmetad_pvscan_single(struct metadata_area *mda, void *baton)
 {
 	struct _lvmetad_pvscan_baton *b = baton;
+	struct device *mda_dev = mda_get_device(mda);
+	struct label_read_data *ld;
 	struct volume_group *vg;
 
+	ld = get_label_read_data(b->cmd, mda_dev);
+
 	if (mda_is_ignored(mda) ||
-	    !(vg = mda->ops->vg_read(b->fid, "", mda, NULL, NULL, NULL)))
+	    !(vg = mda->ops->vg_read(b->fid, "", mda, ld, NULL, NULL)))
 		return 1;
 
 	/* FIXME Also ensure contents match etc. */
@@ -1860,6 +1865,7 @@ scan_more:
 
 		info = (struct lvmcache_info *) label->info;
 
+		baton.cmd = cmd;
 		baton.vg = NULL;
 		baton.fid = lvmcache_fmt(info)->ops->create_instance(lvmcache_fmt(info), &fic);
 		if (!baton.fid)
@@ -2087,15 +2093,21 @@ int lvmetad_pvscan_single(struct cmd_context *cmd, struct device *dev,
 		return 1;
 	}
 
-	if (!label_read(dev, &label, 0)) {
-		log_print_unless_silent("No PV label found on %s.", dev_name(dev));
+	if (!(info = lvmcache_info_from_pvid(dev->pvid, dev, 0))) {
+		log_print_unless_silent("No PV info found on %s for PVID %s.", dev_name(dev), dev->pvid);
 		if (!lvmetad_pv_gone_by_dev(dev))
 			goto_bad;
 		return 1;
 	}
 
-	info = (struct lvmcache_info *) label->info;
+	if (!(label = lvmcache_get_label(info))) {
+		log_print_unless_silent("No PV label found for %s.", dev_name(dev));
+		if (!lvmetad_pv_gone_by_dev(dev))
+			goto_bad;
+		return 1;
+	}
 
+	baton.cmd = cmd;
 	baton.vg = NULL;
 	baton.fid = lvmcache_fmt(info)->ops->create_instance(lvmcache_fmt(info), &fic);
 
@@ -2185,6 +2197,9 @@ int lvmetad_pvscan_all_devs(struct cmd_context *cmd, int do_wait)
 		replacing_other_update = 1;
 	}
 
+	if (!cmd->use_aio || !label_scan_async(cmd))
+		label_scan_sync(cmd);
+
 	log_verbose("Scanning all devices to update lvmetad.");
 
 	if (!(iter = dev_iter_create(cmd->lvmetad_filter, 1))) {
diff --git a/lib/commands/toolcontext.h b/lib/commands/toolcontext.h
index b7a521be4..6180f9fd7 100644
--- a/lib/commands/toolcontext.h
+++ b/lib/commands/toolcontext.h
@@ -164,6 +164,7 @@ struct cmd_context {
 	unsigned lv_notify:1;
 	unsigned pv_notify:1;
 	unsigned use_aio:1;
+	unsigned pvscan_cache_single:1;
 
 	/*
 	 * Filtering.
diff --git a/lib/format_text/format-text.c b/lib/format_text/format-text.c
index ac70947c2..8bf0fca77 100644
--- a/lib/format_text/format-text.c
+++ b/lib/format_text/format-text.c
@@ -1784,15 +1784,18 @@ static struct metadata_area_ops _metadata_text_raw_ops = {
 	.mda_import_text = _mda_import_text_raw
 };
 
+/* used only for sending info to lvmetad */
+
 static int _mda_export_text_raw(struct metadata_area *mda,
 				struct dm_config_tree *cft,
 				struct dm_config_node *parent)
 {
 	struct mda_context *mdc = (struct mda_context *) mda->metadata_locn;
-	char mdah[MDA_HEADER_SIZE]; /* temporary */
 
-	if (!mdc || !_raw_read_mda_header((struct mda_header *)mdah, &mdc->area, NULL))
+	if (!mdc) {
+		log_error(INTERNAL_ERROR "mda_export_text_raw no mdc");
 		return 1; /* pretend the MDA does not exist */
+	}
 
 	return config_make_nodes(cft, parent, NULL,
 				 "ignore = %" PRId64, (int64_t) mda_is_ignored(mda),
@@ -1802,6 +1805,8 @@ static int _mda_export_text_raw(struct metadata_area *mda,
 				 NULL) ? 1 : 0;
 }
 
+/* used only for receiving info from lvmetad */
+
 static int _mda_import_text_raw(struct lvmcache_info *info, const struct dm_config_node *cn)
 {
 	struct device *device;
diff --git a/lib/format_text/import.c b/lib/format_text/import.c
index 7dac1b86e..088207448 100644
--- a/lib/format_text/import.c
+++ b/lib/format_text/import.c
@@ -256,7 +256,7 @@ struct volume_group *text_read_metadata_file(struct format_instance *fid,
 
 static struct volume_group *_import_vg_from_config_tree(const struct dm_config_tree *cft,
 							struct format_instance *fid,
-							unsigned allow_lvmetad_extensions)
+							unsigned for_lvmetad)
 {
 	struct volume_group *vg = NULL;
 	struct text_vg_version_ops **vsn;
@@ -271,7 +271,7 @@ static struct volume_group *_import_vg_from_config_tree(const struct dm_config_t
 		 * The only path to this point uses cached vgmetadata,
 		 * so it can use cached PV state too.
 		 */
-		if (!(vg = (*vsn)->read_vg(fid, cft, allow_lvmetad_extensions)))
+		if (!(vg = (*vsn)->read_vg(fid, cft, for_lvmetad)))
 			stack;
 		else if ((vg_missing = vg_missing_pv_count(vg))) {
 			log_verbose("There are %d physical volumes missing.",
diff --git a/lib/format_text/import_vsn1.c b/lib/format_text/import_vsn1.c
index b41d83c8f..af69cfc3a 100644
--- a/lib/format_text/import_vsn1.c
+++ b/lib/format_text/import_vsn1.c
@@ -216,12 +216,16 @@ static int _read_pv(struct format_instance *fid,
 	/*
 	 * Convert the uuid into a device.
 	 */
-	if (!(pv->dev = lvmcache_device_from_pvid(fid->fmt->cmd, &pv->id, &pv->label_sector))) {
-		char buffer[64] __attribute__((aligned(8)));
+	if (fid->fmt->cmd && !fid->fmt->cmd->pvscan_cache_single) {
+		if (!(pv->dev = lvmcache_device_from_pvid(fid->fmt->cmd, &pv->id, &pv->label_sector))) {
+			char buffer[64] __attribute__((aligned(8)));
 
-		if (!id_write_format(&pv->id, buffer, sizeof(buffer)))
-			buffer[0] = '\0';
-		log_error_once("Couldn't find device with uuid %s.", buffer);
+			if (!id_write_format(&pv->id, buffer, sizeof(buffer)))
+				buffer[0] = '\0';
+			log_error_once("Couldn't find device with uuid %s.", buffer);
+		}
+	} else {
+		log_debug_metadata("Skip metadata pvid to device lookup for lvmetad pvscan.");
 	}
 
 	if (!(pv->vg_name = dm_pool_strdup(mem, vg->name)))
@@ -984,7 +988,7 @@ static int _read_sections(struct format_instance *fid,
 
 static struct volume_group *_read_vg(struct format_instance *fid,
 				     const struct dm_config_tree *cft,
-				     unsigned allow_lvmetad_extensions)
+				     unsigned for_lvmetad)
 {
 	const struct dm_config_node *vgn;
 	const struct dm_config_value *cv;
@@ -1151,7 +1155,7 @@ static struct volume_group *_read_vg(struct format_instance *fid,
 		goto bad;
 	}
 
-	if (allow_lvmetad_extensions)
+	if (for_lvmetad)
 		_read_sections(fid, "outdated_pvs", _read_pv, vg,
 			       vgn, pv_hash, lv_hash, 1);
 	else if (dm_config_has_node(vgn, "outdated_pvs"))
diff --git a/tools/lvmcmdline.c b/tools/lvmcmdline.c
index ba7ff768e..de22af414 100644
--- a/tools/lvmcmdline.c
+++ b/tools/lvmcmdline.c
@@ -2797,7 +2797,7 @@ int lvm_run_command(struct cmd_context *cmd, int argc, char **argv)
 	cmd->position_argv = argv;
 
 	set_cmd_name(cmd->name);
-
+	
 	if (arg_is_set(cmd, backgroundfork_ARG)) {
 		if (!become_daemon(cmd, 1)) {
 			/* parent - quit immediately */
diff --git a/tools/pvscan.c b/tools/pvscan.c
index 6581990f8..396e6a4ce 100644
--- a/tools/pvscan.c
+++ b/tools/pvscan.c
@@ -434,8 +434,10 @@ static int _pvscan_cache(struct cmd_context *cmd, int argc, char **argv)
 	 *  to drop any devices that have left.)
 	 */
 
-	if (argc || devno_args)
+	if (argc || devno_args) {
 		log_verbose("Scanning devices on command line.");
+		cmd->pvscan_cache_single = 1;
+	}
 
 	while (argc--) {
 		pv_name = *argv++;
@@ -453,6 +455,12 @@ static int _pvscan_cache(struct cmd_context *cmd, int argc, char **argv)
 			} else {
 				/* Add device path to lvmetad. */
 				log_debug("Scanning dev %s for lvmetad cache.", pv_name);
+
+				/* FIXME: add a label read async for single dev to use here */
+				if (!label_read(dev, NULL, 0)) {
+					add_errors++;
+					continue;
+				}
 				if (!lvmetad_pvscan_single(cmd, dev, &found_vgnames, &pp.changed_vgnames))
 					add_errors++;
 			}
@@ -471,6 +479,12 @@ static int _pvscan_cache(struct cmd_context *cmd, int argc, char **argv)
 			} else {
 				/* Add major:minor to lvmetad. */
 				log_debug("Scanning dev %d:%d for lvmetad cache.", major, minor);
+
+				/* FIXME: add a label read async for single dev to use here */
+				if (!label_read(dev, NULL, 0)) {
+					add_errors++;
+					continue;
+				}
 				if (!lvmetad_pvscan_single(cmd, dev, &found_vgnames, &pp.changed_vgnames))
 					add_errors++;
 			}