Add --dump / --restore functionality.

[thirdparty/mdadm.git] / super-intel.c

diff --git a/super-intel.c b/super-intel.c
index 2cb28b04b2dcf621611666d9b3fb0bc5b41a1ba8..e0b86b6c6a2b453916642e2e5b6b474a7ef6f94a 100644 (file)
--- a/super-intel.c
+++ b/super-intel.c
@@ -1510,6 +1510,59 @@ static void export_examine_super_imsm(struct supertype *st)
        printf("MD_DEVICES=%u\n", mpb->num_disks);
 }
 
+static int copy_metadata_imsm(struct supertype *st, int from, int to)
+{
+       /* The second last 512byte sector of the device contains
+        * the "struct imsm_super" metadata.
+        * This contains mpb_size which is the size in bytes of the
+        * extended metadata.  This is located immediately before
+        * the imsm_super.
+        * We want to read all that, plus the last sector which
+        * may contain a migration record, and write it all
+        * to the target.
+        */
+       void *buf;
+       unsigned long long dsize, offset;
+       int sectors;
+       struct imsm_super *sb;
+       int written = 0;
+
+       if (posix_memalign(&buf, 4096, 4096) != 0)
+               return 1;
+
+       if (!get_dev_size(from, NULL, &dsize))
+               goto err;
+
+       if (lseek64(from, dsize-1024, 0) < 0)
+               goto err;
+       if (read(from, buf, 512) != 512)
+               goto err;
+       sb = buf;
+       if (strncmp((char*)sb->sig, MPB_SIGNATURE, MPB_SIG_LEN) != 0)
+               goto err;
+
+       sectors = mpb_sectors(sb) + 2;
+       offset = dsize - sectors * 512;
+       if (lseek64(from, offset, 0) < 0 ||
+           lseek64(to, offset, 0) < 0)
+               goto err;
+       while (written < sectors * 512) {
+               int n = sectors*512 - written;
+               if (n > 4096)
+                       n = 4096;
+               if (read(from, buf, n) != n)
+                       goto err;
+               if (write(to, buf, n) != n)
+                       goto err;
+               written += n;
+       }
+       free(buf);
+       return 0;
+err:
+       free(buf);
+       return 1;
+}
+
 static void detail_super_imsm(struct supertype *st, char *homehost)
 {
        struct mdinfo info;
@@ -10463,6 +10516,7 @@ struct superswitch super_imsm = {
        .reshape_super  = imsm_reshape_super,
        .manage_reshape = imsm_manage_reshape,
        .recover_backup = recover_backup_imsm,
+       .copy_metadata = copy_metadata_imsm,
 #endif
        .match_home     = match_home_imsm,
        .uuid_from_super= uuid_from_super_imsm,