1 files changed, 155 insertions, 47 deletions

diff --git a/lib/format_text/text_label.c b/lib/format_text/text_label.c
index 7d10e065b..f95d3ea61 100644
--- a/lib/format_text/text_label.c
+++ b/lib/format_text/text_label.c
@@ -240,11 +240,10 @@ void del_bas(struct dm_list *bas)
 	del_das(bas);
 }
 
-/* FIXME: refactor this function with other mda constructor code */
 int add_mda(const struct format_type *fmt, struct dm_pool *mem, struct dm_list *mdas,
-	    struct device *dev, uint64_t start, uint64_t size, unsigned ignored)
+	    struct device *dev, uint64_t start, uint64_t size, unsigned ignored,
+	    struct metadata_area **mda_new)
 {
-/* FIXME List size restricted by pv_header SECTOR_SIZE */
 	struct metadata_area *mdal, *mda;
 	struct mda_lists *mda_lists = (struct mda_lists *) fmt->private;
 	struct mda_context *mdac, *mdac2;
@@ -294,9 +293,18 @@ int add_mda(const struct format_type *fmt, struct dm_pool *mem, struct dm_list *
 	mda_set_ignored(mdal, ignored);
 
 	dm_list_add(mdas, &mdal->list);
+	if (mda_new)
+		*mda_new = mdal;
 	return 1;
 }
 
+static void _del_mda(struct metadata_area *mda)
+{
+	dm_free(mda->metadata_locn);
+	dm_list_del(&mda->list);
+	dm_free(mda);
+}
+
 void del_mdas(struct dm_list *mdas)
 {
 	struct dm_list *mdah, *tmp;
@@ -304,9 +312,7 @@ void del_mdas(struct dm_list *mdas)
 
 	dm_list_iterate_safe(mdah, tmp, mdas) {
 		mda = dm_list_item(mdah, struct metadata_area);
-		dm_free(mda->metadata_locn);
-		dm_list_del(&mda->list);
-		dm_free(mda);
+		_del_mda(mda);
 	}
 }
 
@@ -318,72 +324,84 @@ static int _text_initialise_label(struct labeller *l __attribute__((unused)),
 	return 1;
 }
 
-struct _update_mda_baton {
-	struct lvmcache_info *info;
-	struct label *label;
-};
-
-static int _read_mda_header_and_metadata(struct metadata_area *mda, void *baton)
+static int _read_mda_header_and_metadata(const struct format_type *fmt,
+					 struct metadata_area *mda, int mda_num,
+					 struct lvmcache_vgsummary *vgsummary)
 {
-	struct _update_mda_baton *p = baton;
-	const struct format_type *fmt = p->label->labeller->fmt;
 	struct mda_context *mdac = (struct mda_context *) mda->metadata_locn;
 	struct mda_header *mdah;
-	struct lvmcache_vgsummary vgsummary = { 0 };
 
 	if (!(mdah = raw_read_mda_header(fmt, &mdac->area, mda_is_primary(mda)))) {
-		log_error("Failed to read mda header from %s", dev_name(mdac->area.dev));
-		goto fail;
+		log_warn("WARNING: bad metadata header on %s at %llu.",
+			 dev_name(mdac->area.dev),
+			 (unsigned long long)mdac->area.start);
+		return 0;
 	}
 
+	if (mda)
+		mda->header_start = mdah->start;
+
 	mda_set_ignored(mda, rlocn_is_ignored(mdah->raw_locns));
 
 	if (mda_is_ignored(mda)) {
 		log_debug_metadata("Ignoring mda on device %s at offset " FMTu64,
 				   dev_name(mdac->area.dev),
 				   mdac->area.start);
+		vgsummary->mda_ignored = 1;
 		return 1;
 	}
 
 	if (!read_metadata_location_summary(fmt, mdah, mda_is_primary(mda), &mdac->area,
-					    &vgsummary, &mdac->free_sectors)) {
-		if (vgsummary.zero_offset)
+					    vgsummary, &mdac->free_sectors)) {
+		if (vgsummary->zero_offset)
 			return 1;
 
-		log_error("Failed to read metadata summary from %s", dev_name(mdac->area.dev));
-		goto fail;
-	}
-
-	if (!lvmcache_update_vgname_and_id(p->info, &vgsummary)) {
-		log_error("Failed to save lvm summary for %s", dev_name(mdac->area.dev));
-		goto fail;
+		log_warn("WARNING: bad metadata text on %s in mda%d",
+			 dev_name(mdac->area.dev), mda_num);
+		return 0;
 	}
 
 	return 1;
-
-fail:
-	lvmcache_del(p->info);
-	return 0;
 }
 
-static int _text_read(struct labeller *l, struct device *dev, void *label_buf,
+/*
+ * Used by label_scan to get a summary of the VG that exists on this PV.  This
+ * summary is stored in lvmcache vginfo/info/info->mdas and is used later by
+ * vg_read which needs to know which PVs to read for a given VG name, and where
+ * the metadata is at for those PVs.
+ */
+
+static int _text_read(struct labeller *labeller, struct device *dev, void *label_buf,
 		      struct label **label)
 {
+	struct lvmcache_vgsummary vgsummary;
+	struct lvmcache_info *info;
+	const struct format_type *fmt = labeller->fmt;
 	struct label_header *lh = (struct label_header *) label_buf;
 	struct pv_header *pvhdr;
 	struct pv_header_extension *pvhdr_ext;
-	struct lvmcache_info *info;
+	struct metadata_area *mda;
+	struct metadata_area *mda1 = NULL;
+	struct metadata_area *mda2 = NULL;
 	struct disk_locn *dlocn_xl;
 	uint64_t offset;
 	uint32_t ext_version;
-	struct _update_mda_baton baton;
+	int mda_count = 0;
+	int good_mda_count = 0;
+	int bad_mda_count = 0;
+	int mda1_bad = 0;
+	int mda2_bad = 0;
+	int rv1, rv2;
 
 	/*
 	 * PV header base
 	 */
 	pvhdr = (struct pv_header *) ((char *) label_buf + xlate32(lh->offset_xl));
 
-	if (!(info = lvmcache_add(l, (char *)pvhdr->pv_uuid, dev,
+	/* FIXME: errors from lvmcache_add need to be handled better */
+	/* FIXME: stop pretending that the PV is initially an orphan. */
+
+	if (!(info = lvmcache_add(labeller, (char *)pvhdr->pv_uuid, dev,
 				  FMT_TEXT_ORPHAN_VG_NAME,
 				  FMT_TEXT_ORPHAN_VG_NAME, 0)))
 		return_0;
@@ -403,11 +421,23 @@ static int _text_read(struct labeller *l, struct device *dev, void *label_buf,
 		dlocn_xl++;
 	}
 
-	/* Metadata area headers */
 	dlocn_xl++;
+
+	/* Metadata areas */
 	while ((offset = xlate64(dlocn_xl->offset))) {
-		lvmcache_add_mda(info, dev, offset, xlate64(dlocn_xl->size), 0);
+
+		/*
+		 * This just calls add_mda() above, replacing info with info->mdas.
+		 */
+		lvmcache_add_mda(info, dev, offset, xlate64(dlocn_xl->size), 0, &mda);
+
 		dlocn_xl++;
+		mda_count++;
+
+		if (mda_count == 1)
+			mda1 = mda;
+		else if (mda_count == 2)
+			mda2 = mda;
 	}
 
 	dlocn_xl++;
@@ -417,7 +447,7 @@ static int _text_read(struct labeller *l, struct device *dev, void *label_buf,
 	 */
 	pvhdr_ext = (struct pv_header_extension *) ((char *) dlocn_xl);
 	if (!(ext_version = xlate32(pvhdr_ext->version)))
-		goto out;
+		goto scan_mdas;
 
 	log_debug_metadata("%s: PV header extension version " FMTu32 " found",
 			   dev_name(dev), ext_version);
@@ -434,22 +464,100 @@ static int _text_read(struct labeller *l, struct device *dev, void *label_buf,
 		lvmcache_add_ba(info, offset, xlate64(dlocn_xl->size));
 		dlocn_xl++;
 	}
-out:
-	baton.info = info;
-	baton.label = *label;
+
+ scan_mdas:
+	if (!mda_count) {
+		log_debug_metadata("Scanning %s found no mdas.", dev_name(dev));
+		return 1;
+	}
+
+	if (mda1) {
+		log_debug_metadata("Scanning %s mda1 summary.", dev_name(dev));
+		memset(&vgsummary, 0, sizeof(vgsummary));
+		vgsummary.mda_num = 1;
+
+		rv1 = _read_mda_header_and_metadata(fmt, mda1, 1, &vgsummary);
+
+		if (rv1 && !vgsummary.zero_offset && !vgsummary.mda_ignored) {
+			if (!lvmcache_update_vgname_and_id(info, &vgsummary)) {
+				/* I believe this is only an internal error. */
+				log_warn("Scanning %s mda1 failed to save summary.", dev_name(dev));
+				_del_mda(mda1);
+				mda1 = NULL;
+				mda1_bad = 1;
+				bad_mda_count++;
+			} else {
+				log_warn("Scanned %s mda1 seqno %u", dev_name(dev), vgsummary.seqno);
+				good_mda_count++;
+			}
+		}
+
+		if (!rv1) {
+			/* Remove the bad mda so vg_read won't try to read it. */
+			log_warn("WARNING: scanning %s mda1 failed to read metadata summary.", dev_name(dev));
+			log_warn("WARNING: repair VG metadata on %s with vgck --repairmetadata.", dev_name(dev));
+			_del_mda(mda1);
+			mda1 = NULL;
+			mda1_bad = 1;
+			bad_mda_count++;
+		}
+	}
+
+	if (mda2) {
+		log_debug_metadata("Scanning %s mda2 summary.", dev_name(dev));
+		memset(&vgsummary, 0, sizeof(vgsummary));
+		vgsummary.mda_num = 2;
+
+		rv2 = _read_mda_header_and_metadata(fmt, mda2, 2, &vgsummary);
+
+		if (rv2 && !vgsummary.zero_offset && !vgsummary.mda_ignored) {
+			if (!lvmcache_update_vgname_and_id(info, &vgsummary)) {
+				/* I believe this is only an internal error. */
+				log_warn("Scanning %s mda2 failed to save summary.", dev_name(dev));
+				_del_mda(mda2);
+				mda2 = NULL;
+				mda2_bad = 1;
+				bad_mda_count++;
+			} else {
+				log_warn("Scanned %s mda2 seqno %u", dev_name(dev), vgsummary.seqno);
+				good_mda_count++;
+			}
+		}
+
+		if (!rv2) {
+			/* Remove the bad mda so vg_read won't try to read it. */
+			log_warn("WARNING: scanning %s mda2 failed to read metadata summary.", dev_name(dev));
+			log_warn("WARNING: repair VG metadata on %s with vgck --repairmetadata.", dev_name(dev));
+			_del_mda(mda2);
+			mda2 = NULL;
+			mda2_bad = 1;
+			bad_mda_count++;
+		}
+	}
+
+	log_debug_metadata("Scanning %s found mda_count %d mda1_bad %d mda2_bad %d",
+			   dev_name(dev), mda_count, mda1_bad, mda2_bad);
 
 	/*
-	 * In the vg_read phase, we compare all mdas and decide which to use
-	 * which are bad and need repair.
+	 * Track which devs have bad metadata so repair can find them
+	 * (even if this dev also has good metadata that we are able to use).
 	 *
-	 * FIXME: this quits if the first mda is bad, but we need something
-	 * smarter to be able to use the second mda if it's good.
+	 * When bad metadata is seen above, the unusable mda struct is
+	 * removed from lvmcache info->mdas.  This means that vg_read will
+	 * skip the bad mda not try to read the bad metadata.  It also means
+	 * that vg_write will also skip the bad mda and not try to write
+	 * new metadata to it.
 	 */
-	if (!lvmcache_foreach_mda(info, _read_mda_header_and_metadata, &baton)) {
-		log_error("Failed to scan VG from %s", dev_name(dev));
+	if (mda1_bad || mda2_bad)
+		lvmcache_set_bad_metadata(info, mda1_bad, mda2_bad);
+
+	if (good_mda_count)
+		return 1;
+
+	if (bad_mda_count)
 		return 0;
-	}
 
+	/* no metadata in the mdas */
 	return 1;
 }