ext4: simplify handling of the errors=* mount options

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

fs/ext4/ext4.h

@@ -924,6 +924,7 @@ struct ext4_inode_info {
 #define EXT4_MOUNT_ERRORS_CONT		0x00010	/* Continue on errors */
 #define EXT4_MOUNT_ERRORS_RO		0x00020	/* Remount fs ro on errors */
 #define EXT4_MOUNT_ERRORS_PANIC		0x00040	/* Panic on errors */
+#define EXT4_MOUNT_ERRORS_MASK		0x00070
 #define EXT4_MOUNT_MINIX_DF		0x00080	/* Mimics the Minix statfs */
 #define EXT4_MOUNT_NOLOAD		0x00100	/* Don't use existing journal*/
 #define EXT4_MOUNT_DATA_FLAGS		0x00C00	/* Mode for data writes: */

fs/ext4/super.c

@@ -1565,18 +1565,15 @@ static int parse_options(char *options, struct super_block *sb,
 			/* *sb_block = match_int(&args[0]); */
 			break;
 		case Opt_err_panic:
-			clear_opt(sb, ERRORS_CONT);
-			clear_opt(sb, ERRORS_RO);
+			clear_opt(sb, ERRORS_MASK);
 			set_opt(sb, ERRORS_PANIC);
 			break;
 		case Opt_err_ro:
-			clear_opt(sb, ERRORS_CONT);
-			clear_opt(sb, ERRORS_PANIC);
+			clear_opt(sb, ERRORS_MASK);
 			set_opt(sb, ERRORS_RO);
 			break;
 		case Opt_err_cont:
-			clear_opt(sb, ERRORS_RO);
-			clear_opt(sb, ERRORS_PANIC);
+			clear_opt(sb, ERRORS_MASK);
 			set_opt(sb, ERRORS_CONT);
 			break;
 		case Opt_nouid32: