Grow: various fixes to recent breakages.

- I forgot to write the send backup-super-block on spares.
- I wasn't adding the data_offset to an offset

Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/Grow.c b/Grow.c
index 36c35f9c71c65b26bf544a1bd5ee11326fa824b9..7764bdb6275d728ea5826593b3f8158aabb74f19 100644 (file)
--- a/Grow.c
+++ b/Grow.c
@@ -381,7 +381,7 @@ int Grow_addbitmap(char *devname, int fd, char *file, int chunk, int delay, int
 /*
  * When reshaping an array we might need to backup some data.
  * This is written to all spares with a 'super_block' describing it.
- * The superblock goes 1K form the end of the used space on the
+ * The superblock goes 4K from the end of the used space on the
  * device.
  * It if written after the backup is complete.
  * It has the following structure.
@@ -982,7 +982,7 @@ int Grow_reshape(char *devname, int fd, int quiet, char *backup_file,
                                char *dn = map_dev(sd->disk.major,
                                                   sd->disk.minor, 1);
                                fdlist[d] = dev_open(dn, O_RDWR);
-                               offsets[d] = (sra->component_size - blocks - 8)*512;
+                               offsets[d] = (sd->data_offset + sra->component_size - blocks - 8)*512;
                                if (fdlist[d]<0) {
                                        fprintf(stderr, Name ": %s: cannot open component %s\n",
                                                devname, dn?dn:"-unknown");
@@ -1308,6 +1308,10 @@ int grow_backup(struct mdinfo *sra,
 
                lseek64(destfd[i], destoffsets[i] - 4096, 0);
                write(destfd[i], &bsb, 512);
+               if (destoffsets[i] > 4096) {
+                       lseek64(destfd[i], destoffsets[i]+stripes*chunk*odata, 0);
+                       write(destfd[i], &bsb, 512);
+               }
                fsync(destfd[i]);
        }
 
@@ -1628,7 +1632,6 @@ int Grow_restart(struct supertype *st, struct mdinfo *info, int *fdlist, int cnt
                old_disks = cnt;
        for (i=old_disks-(backup_file?1:0); i<cnt; i++) {
                struct mdinfo dinfo;
-               char buf[4096];
                int fd;
                int bsbsize;
                char *devname, namebuf[20];
@@ -1744,13 +1747,13 @@ int Grow_restart(struct supertype *st, struct mdinfo *info, int *fdlist, int cnt
                }
                /* There should be a duplicate backup superblock 4k before here */
                if (lseek64(fd, -4096, 1) < 0 ||
-                   read(fd, buf, 4096) != 4096)
+                   read(fd, &bsb2, 4096) != 4096)
                        goto second_fail; /* Cannot find leading superblock */
                if (bsb.magic[15] == '1')
                        bsbsize = offsetof(struct mdp_backup_super, pad1);
                else
                        bsbsize = offsetof(struct mdp_backup_super, pad);
-               if (memcmp(buf, &bsb, bsbsize) != 0)
+               if (memcmp(&bsb2, &bsb, bsbsize) != 0)
                        goto second_fail; /* Cannot find leading superblock */
 
                /* Now need the data offsets for all devices. */