imsm: fix/support --update

Fix init_super_imsm() to return an empty mpb when info == NULL, and
teach store_super_imsm() to simply write out the passed in mpb.

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=523320
Reported-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/super-intel.c b/super-intel.c
index 0e3ed89416a85157e022555647c7c0953f0d8725..eaf5b0b8e6f979051ce48425a8222636f686eca1 100644 (file)
--- a/super-intel.c
+++ b/super-intel.c
@@ -2819,24 +2819,33 @@ static int init_super_imsm(struct supertype *st, mdu_array_info_t *info,
        size_t mpb_size;
        char *version;
 
-       if (!info) {
-               st->sb = NULL;
-               return 0;
-       }
        if (st->sb)
-               return init_super_imsm_volume(st, info, size, name, homehost,
-                                             uuid);
+               return init_super_imsm_volume(st, info, size, name, homehost, uuid);
+
+       if (info)
+               mpb_size = disks_to_mpb_size(info->nr_disks);
+       else
+               mpb_size = 512;
 
        super = alloc_super(1);
-       if (!super)
-               return 0;
-       mpb_size = disks_to_mpb_size(info->nr_disks);
-       if (posix_memalign(&super->buf, 512, mpb_size) != 0) {
+       if (super && posix_memalign(&super->buf, 512, mpb_size) != 0) {
                free(super);
+               super = NULL;
+       }
+       if (!super) {
+               fprintf(stderr, Name
+                       ": %s could not allocate superblock\n", __func__);
                return 0;
        }
+       memset(super->buf, 0, mpb_size);
        mpb = super->buf;
-       memset(mpb, 0, mpb_size); 
+       mpb->mpb_size = __cpu_to_le32(mpb_size);
+       st->sb = super;
+
+       if (info == NULL) {
+               /* zeroing superblock */
+               return 0;
+       }
 
        mpb->attributes = MPB_ATTRIB_CHECKSUM_VERIFY;
 
@@ -2844,9 +2853,7 @@ static int init_super_imsm(struct supertype *st, mdu_array_info_t *info,
        strcpy(version, MPB_SIGNATURE);
        version += strlen(MPB_SIGNATURE);
        strcpy(version, MPB_VERSION_RAID0);
-       mpb->mpb_size = mpb_size;
 
-       st->sb = super;
        return 1;
 }
 
@@ -3188,24 +3195,15 @@ static int write_init_super_imsm(struct supertype *st)
 }
 #endif
 
-static int store_zero_imsm(struct supertype *st, int fd)
+static int store_super_imsm(struct supertype *st, int fd)
 {
-       unsigned long long dsize;
-       void *buf;
-
-       get_dev_size(fd, NULL, &dsize);
-
-       /* first block is stored on second to last sector of the disk */
-       if (lseek64(fd, dsize - (512 * 2), SEEK_SET) < 0)
-               return 1;
+       struct intel_super *super = st->sb;
+       struct imsm_super *mpb = super ? super->anchor : NULL;
 
-       if (posix_memalign(&buf, 512, 512) != 0)
+       if (!mpb)
                return 1;
 
-       memset(buf, 0, 512);
-       if (write(fd, buf, 512) != 512)
-               return 1;
-       return 0;
+       return store_imsm_mpb(fd, mpb);
 }
 
 static int imsm_bbm_log_size(struct imsm_super *mpb)
@@ -4914,7 +4912,7 @@ struct superswitch super_imsm = {
 
        .load_super     = load_super_imsm,
        .init_super     = init_super_imsm,
-       .store_super    = store_zero_imsm,
+       .store_super    = store_super_imsm,
        .free_super     = free_super_imsm,
        .match_metadata_desc = match_metadata_desc_imsm,
        .container_content = container_content_imsm,