[thin_check] --ignore-non-fatal-errors

features/thin_check.feature

@@ -39,6 +39,7 @@ Feature: thin_check
       {-V|--version}
       {--super-block-only}
       {--skip-mappings}
+      {--ignore-non-fatal-errors}
     """
 
   Scenario: Unrecognised option should cause failure
@@ -64,3 +65,8 @@ Feature: thin_check
     Given valid metadata
     When I run thin_check with --skip-mappings
     Then it should pass
+
+  Scenario: --ignore-non-fatal-errors check passes on valid metadata
+    Given valid metadata
+    When I run thin_check with --ignore-non-fatal-errors
+    Then it should pass

man8/thin_check.8

@@ -32,6 +32,14 @@ Only check the superblock is present.
 Skip checking of the block mappings which make up the bulk of the
 metadata.
 
+.IP "\fB\-\-ignore\-non\-fatal\-errors\fP"
+.B thin_check
+will only return a non-zero exit code if it finds a fatal
+error.  An example of a on fatal error is an incorrect data block
+reference count causing a block to be considered allocated when it in
+fact isn't.  Ignoring errors for a long time is not advised, you
+really should be using thin_repair to fix them.
+
 .SH EXAMPLE
 Analyses and repairs thin provisioning metadata on logical volume
 /dev/vg/metadata:

thin-provisioning/thin_check.cc

@@ -233,6 +233,8 @@ namespace {
 		bool check_device_tree;
 		bool check_mapping_tree_level1;
 		bool check_mapping_tree_level2;
+
+		bool ignore_non_fatal_errors;
 	};
 
 	error_state metadata_check(string const &path, flags fs) {
@@ -299,7 +301,10 @@ namespace {
 			return 1;
 		}
 
-		return (err == NO_ERROR) ? 0 : 1;
+		if (fs.ignore_non_fatal_errors)
+			return (err == FATAL) ? 1 : 0;
+		else
+			return (err == NO_ERROR) ? 0 : 1;
 	}
 
 	void usage(ostream &out, string const &cmd) {
@@ -309,7 +314,8 @@ namespace {
 		    << "  {-h|--help}" << endl
 		    << "  {-V|--version}" << endl
 		    << "  {--super-block-only}" << endl
-		    << "  {--skip-mappings}" << endl;
+		    << "  {--skip-mappings}" << endl
+		    << "  {--ignore-non-fatal-errors}" << endl;
 	}
 }
 
@@ -325,12 +331,14 @@ int main(int argc, char **argv)
 		{ "version", no_argument, NULL, 'V'},
 		{ "super-block-only", no_argument, NULL, 1},
 		{ "skip-mappings", no_argument, NULL, 2},
+		{ "ignore-non-fatal-errors", no_argument, NULL, 3},
 		{ NULL, no_argument, NULL, 0 }
 	};
 
 	fs.check_device_tree = true;
 	fs.check_mapping_tree_level1 = true;
 	fs.check_mapping_tree_level2 = true;
+	fs.ignore_non_fatal_errors = false;
 
 	while ((c = getopt_long(argc, argv, shortopts, longopts, NULL)) != -1) {
 		switch(c) {
@@ -358,6 +366,11 @@ int main(int argc, char **argv)
 			fs.check_mapping_tree_level2 = false;
 			break;
 
+		case 3:
+			// ignore-non-fatal-errors
+			fs.ignore_non_fatal_errors = true;
+			break;
+
 		default:
 			usage(cerr, basename(argv[0]));
 			return 1;