Merge pull request #66 from lorelei-sakai/feature/mitigate-old-recove…

…ry-journal-issues

[VDO-5742] Mitigate old recovery journal issues

drivers/md/dm-vdo/dm-vdo-target.c

@@ -2296,6 +2296,14 @@ static void handle_load_error(struct vdo_completion *completion)
 		return;
 	}
 
+	if ((completion->result == VDO_UNSUPPORTED_VERSION) &&
+	    (vdo->admin.phase == LOAD_PHASE_MAKE_DIRTY)) {
+		vdo_log_error("Aborting load due to unsupported version");
+		vdo->admin.phase = LOAD_PHASE_FINISHED;
+		load_callback(completion);
+		return;
+	}
+
 	vdo_log_error_strerror(completion->result,
 			       "Entering read-only mode due to load error");
 	vdo->admin.phase = LOAD_PHASE_WAIT_FOR_READ_ONLY;
@@ -2740,6 +2748,19 @@ static int vdo_preresume_registered(struct dm_target *ti, struct vdo *vdo)
 		vdo_log_info("starting device '%s'", device_name);
 		result = perform_admin_operation(vdo, LOAD_PHASE_START, load_callback,
 						 handle_load_error, "load");
+		if (result == VDO_UNSUPPORTED_VERSION) {
+			 /*
+			  * A component version is not supported. This can happen when the
+			  * recovery journal metadata is in an old version format. Abort the
+			  * load without saving the state.
+			  */
+			vdo->suspend_type = VDO_ADMIN_STATE_SUSPENDING;
+			perform_admin_operation(vdo, SUSPEND_PHASE_START,
+						suspend_callback, suspend_callback,
+						"suspend");
+			return result;
+		}
+
 		if ((result != VDO_SUCCESS) && (result != VDO_READ_ONLY)) {
 			/*
 			 * Something has gone very wrong. Make sure everything has drained and
@@ -2811,7 +2832,8 @@ static int vdo_preresume(struct dm_target *ti)
 
 	vdo_register_thread_device_id(&instance_thread, &vdo->instance);
 	result = vdo_preresume_registered(ti, vdo);
-	if ((result == VDO_PARAMETER_MISMATCH) || (result == VDO_INVALID_ADMIN_STATE))
+	if ((result == VDO_PARAMETER_MISMATCH) || (result == VDO_INVALID_ADMIN_STATE) ||
+	    (result == VDO_UNSUPPORTED_VERSION))
 		result = -EINVAL;
 	vdo_unregister_thread_device_id();
 	return vdo_status_to_errno(result);

drivers/md/dm-vdo/repair.c

@@ -1201,17 +1201,14 @@ static bool __must_check is_valid_recovery_journal_block(const struct recovery_j
  * @journal: The journal to use.
  * @header: The unpacked block header to check.
  * @sequence: The expected sequence number.
- * @type: The expected metadata type.
  *
  * Return: True if the block matches.
  */
 static bool __must_check is_exact_recovery_journal_block(const struct recovery_journal *journal,
 							 const struct recovery_block_header *header,
-							 sequence_number_t sequence,
-							 enum vdo_metadata_type type)
+							 sequence_number_t sequence)
 {
-	return ((header->metadata_type == type) &&
-		(header->sequence_number == sequence) &&
+	return ((header->sequence_number == sequence) &&
 		(is_valid_recovery_journal_block(journal, header, true)));
 }
 
@@ -1370,7 +1367,8 @@ static void extract_entries_from_block(struct repair_completion *repair,
 		get_recovery_journal_block_header(journal, repair->journal_data,
 						  sequence);
 
-	if (!is_exact_recovery_journal_block(journal, &header, sequence, format)) {
+	if (!is_exact_recovery_journal_block(journal, &header, sequence) ||
+	    (header.metadata_type != format)) {
 		/* This block is invalid, so skip it. */
 		return;
 	}
@@ -1556,10 +1554,13 @@ static int parse_journal_for_recovery(struct repair_completion *repair)
 	sequence_number_t i, head;
 	bool found_entries = false;
 	struct recovery_journal *journal = repair->completion.vdo->recovery_journal;
+	struct recovery_block_header header;
+	enum vdo_metadata_type expected_format;
 
 	head = min(repair->block_map_head, repair->slab_journal_head);
+	header = get_recovery_journal_block_header(journal, repair->journal_data, head);
+	expected_format = header.metadata_type;
 	for (i = head; i <= repair->highest_tail; i++) {
-		struct recovery_block_header header;
 		journal_entry_count_t block_entries;
 		u8 j;
 
@@ -1571,19 +1572,15 @@ static int parse_journal_for_recovery(struct repair_completion *repair)
 		};
 
 		header = get_recovery_journal_block_header(journal, repair->journal_data, i);
-		if (header.metadata_type == VDO_METADATA_RECOVERY_JOURNAL) {
-			/* This is an old format block, so we need to upgrade */
-			vdo_log_error_strerror(VDO_UNSUPPORTED_VERSION,
-					       "Recovery journal is in the old format, a read-only rebuild is required.");
-			vdo_enter_read_only_mode(repair->completion.vdo,
-						 VDO_UNSUPPORTED_VERSION);
-			return VDO_UNSUPPORTED_VERSION;
-		}
-
-		if (!is_exact_recovery_journal_block(journal, &header, i,
-						     VDO_METADATA_RECOVERY_JOURNAL_2)) {
+		if (!is_exact_recovery_journal_block(journal, &header, i)) {
 			/* A bad block header was found so this must be the end of the journal. */
 			break;
+		} else if (header.metadata_type != expected_format) {
+			/* There is a mix of old and new format blocks, so we need to rebuild. */
+			vdo_log_error_strerror(VDO_CORRUPT_JOURNAL,
+					       "Recovery journal is in an invalid format, a read-only rebuild is required.");
+			vdo_enter_read_only_mode(repair->completion.vdo, VDO_CORRUPT_JOURNAL);
+			return VDO_CORRUPT_JOURNAL;
 		}
 
 		block_entries = header.entry_count;
@@ -1619,8 +1616,14 @@ static int parse_journal_for_recovery(struct repair_completion *repair)
 			break;
 	}
 
-	if (!found_entries)
+	if (!found_entries) {
 		return validate_heads(repair);
+	} else if (expected_format == VDO_METADATA_RECOVERY_JOURNAL) {
+		/* All journal blocks have the old format, so we need to upgrade. */
+		vdo_log_error_strerror(VDO_UNSUPPORTED_VERSION,
+				       "Recovery journal is in the old format. Downgrade and complete recovery, then upgrade with a clean volume");
+		return VDO_UNSUPPORTED_VERSION;
+	}
 
 	/* Set the tail to the last valid tail block, if there is one. */
 	if (repair->tail_recovery_point.sector_count == 0)

drivers/md/dm-vdo/status-codes.c

@@ -28,7 +28,7 @@ const struct error_info vdo_status_list[] = {
 	{ "VDO_LOCK_ERROR", "A lock is held incorrectly" },
 	{ "VDO_READ_ONLY", "The device is in read-only mode" },
 	{ "VDO_SHUTTING_DOWN", "The device is shutting down" },
-	{ "VDO_CORRUPT_JOURNAL", "Recovery journal entries corrupted" },
+	{ "VDO_CORRUPT_JOURNAL", "Recovery journal corrupted" },
 	{ "VDO_TOO_MANY_SLABS", "Exceeds maximum number of slabs supported" },
 	{ "VDO_INVALID_FRAGMENT", "Compressed block fragment is invalid" },
 	{ "VDO_RETRY_AFTER_REBUILD", "Retry operation after rebuilding finishes" },

drivers/md/dm-vdo/status-codes.h

@@ -52,7 +52,7 @@ enum vdo_status_codes {
 	VDO_READ_ONLY,
 	/* the VDO is shutting down */
 	VDO_SHUTTING_DOWN,
-	/* the recovery journal has corrupt entries */
+	/* the recovery journal has corrupt entries or corrupt metadata */
 	VDO_CORRUPT_JOURNAL,
 	/* exceeds maximum number of slabs supported */
 	VDO_TOO_MANY_SLABS,