bcachefs: Don't error out when just reading the journal

This tweaks the recovery and journal paths so that we don't error out
before we need to: the list_journal command should work, even if we
wouldn't be able to replay successfully.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/journal_io.c

@@ -1187,8 +1187,7 @@ int bch2_journal_read(struct bch_fs *c, u64 *blacklist_seq, u64 *start_seq)
 
 	if (!last_seq) {
 		fsck_err(c, "journal read done, but no entries found after dropping non-flushes");
-		ret = -1;
-		goto err;
+		return 0;
 	}
 
 	bch_info(c, "journal read done, replaying entries %llu-%llu",

fs/bcachefs/recovery.c

@@ -1113,6 +1113,13 @@ int bch2_fs_recovery(struct bch_fs *c)
 		if (ret)
 			goto err;
 
+		/*
+		 * note: cmd_list_journal needs the blacklist table fully up to date so
+		 * it can asterisk ignored journal entries:
+		 */
+		if (c->opts.read_journal_only)
+			goto out;
+
 		genradix_for_each_reverse(&c->journal_entries, iter, i)
 			if (*i && !(*i)->ignore) {
 				last_journal_entry = &(*i)->j;
@@ -1184,13 +1191,6 @@ int bch2_fs_recovery(struct bch_fs *c)
 		}
 	}
 
-	/*
-	 * note: cmd_list_journal needs the blacklist table fully up to date so
-	 * it can asterisk ignored journal entries:
-	 */
-	if (c->opts.read_journal_only)
-		goto out;
-
 	ret = bch2_fs_journal_start(&c->journal, journal_seq);
 	if (ret)
 		goto err;