Add btrfsck option to select the super block copy

btrfsck -s 0 uses the defult 0, -s 1 uses copy #1 etc.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/btrfsck.c b/btrfsck.c
index cd2cedd..63e44d1 100644 (file)
--- a/btrfsck.c
+++ b/btrfsck.c
@@ -20,6 +20,7 @@
 #define _GNU_SOURCE 1
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
 #include <fcntl.h>
 #include <sys/stat.h>
 #include "kerncompat.h"
@@ -2819,23 +2820,43 @@ int main(int ac, char **av)
 {
        struct cache_tree root_cache;
        struct btrfs_root *root;
+       u64 bytenr = 0;
        int ret;
+       int num;
 
-       if (ac < 2)
+       while(1) {
+               int c;
+               c = getopt(ac, av, "s:");
+               if (c < 0)
+                       break;
+               switch(c) {
+                       case 's':
+                               num = atol(optarg);
+                               bytenr = btrfs_sb_offset(num);
+                               printf("using SB copy %d, bytenr %llu\n", num,
+                                      (unsigned long long)bytenr);
+                               break;
+                       default:
+                               print_usage();
+               }
+       }
+       ac = ac - optind;
+
+       if (ac != 1)
                print_usage();
 
        radix_tree_init();
        cache_tree_init(&root_cache);
 
-       if((ret = check_mounted(av[1])) < 0) {
+       if((ret = check_mounted(av[optind])) < 0) {
                fprintf(stderr, "Could not check mount status: %s\n", strerror(ret));
                return ret;
        } else if(ret) {
-               fprintf(stderr, "%s is currently mounted. Aborting.\n", av[1]);
+               fprintf(stderr, "%s is currently mounted. Aborting.\n", av[optind]);
                return -EBUSY;
        }
 
-       root = open_ctree(av[1], 0, 0);
+       root = open_ctree(av[optind], bytenr, 0);
 
        if (root == NULL)
                return 1;