Assemble: --update=metadata converts v0.90 to v1.0

[thirdparty/mdadm.git] / super0.c

diff --git a/super0.c b/super0.c
index 061e475e52a70c6a2685879c0aaac33600e34cb6..01c31c27b7ce731129397d5b4821d83067d4be17 100644 (file)
--- a/super0.c
+++ b/super0.c
@@ -625,6 +625,26 @@ static int update_super0(struct supertype *st, struct mdinfo *info,
                        uuid_from_super0(st, uuid);
                        memcpy(bm->uuid, uuid, 16);
                }
+       } else if (strcmp(update, "metadata") == 0) {
+               /* Create some v1.0 metadata to match ours but make the
+                * ctime bigger.  Also update info->array.*_version.
+                * We need to arrange that store_super writes out
+                * the v1.0 metadata.
+                * Not permitted for unclean array, or array with
+                * bitmap.
+                */
+               if (info->bitmap_offset) {
+                       pr_err("Cannot update metadata when bitmap is present\n");
+                       rv = -2;
+               } else if (info->array.state != 1) {
+                       pr_err("Cannot update metadata on unclean array\n");
+                       rv = -2;
+               } else {
+                       info->array.major_version = 1;
+                       info->array.minor_version = 0;
+                       uuid_from_super0(st, info->uuid);
+                       st->other = super1_make_v0(st, info, st->sb);
+               }
        } else if (strcmp(update, "no-bitmap") == 0) {
                sb->state &= ~(1<<MD_SB_BITMAP_PRESENT);
        } else if (strcmp(update, "_reshape_progress")==0)
@@ -788,6 +808,24 @@ static int store_super0(struct supertype *st, int fd)
        if (dsize < MD_RESERVED_SECTORS*512)
                return 2;
 
+       if (st->other) {
+               /* Writing out v1.0 metadata for --update=metadata */
+               int ret;
+
+               offset = dsize/512 - 8*2;
+               offset &= ~(4*2-1);
+               offset *= 512;
+               if (lseek64(fd, offset, 0)< 0LL)
+                       ret = 3;
+               else if (write(fd, st->other, 1024) != 1024)
+                       ret = 4;
+               else
+                       fsync(fd);
+               free(st->other);
+               st->other = NULL;
+               return ret;
+       }
+
        offset = MD_NEW_SIZE_SECTORS(dsize>>9);
 
        offset *= 512;
@@ -915,6 +953,7 @@ static int load_super0(struct supertype *st, int fd, char *devname)
                               devname, dsize);
                return 1;
        }
+       st->devsize = dsize;
 
        offset = MD_NEW_SIZE_SECTORS(dsize>>9);