Grow: set_new_data_offset should report if kernel is too old.

For RAID5, not being able to set new_data_offset because of
old kernel is not a problem.  So make this fatal on for RAID10.

Also remove an unused assignment to 'rv'.

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

diff --git a/Grow.c b/Grow.c
index 3e03c7aa77d0c145b92babd53a1bc063c4815905..ee0fc5e01cb77723425b1d5a7dfb3edba8c44f72 100644 (file)
--- a/Grow.c
+++ b/Grow.c
@@ -2173,7 +2173,6 @@ static int set_new_data_offset(struct mdinfo *sra, struct supertype *st,
                        fprintf(stderr,
                                Name ": %s: cannot open component %s\n",
                                devname, dn ? dn : "-unknown-");
-                       rv = -1;
                        goto release;
                }
                st2 = dup_super(st);
@@ -2293,6 +2292,11 @@ static int set_new_data_offset(struct mdinfo *sra, struct supertype *st,
                if (sysfs_set_num(sra, sd, "new_offset",
                                  info2.new_data_offset) < 0) {
                        err = errno;
+                       if (sd == sra->devs && err == ENOENT)
+                               /* Early kernel, no 'new_offset' file.
+                                * For RAID5/6 this is not fatal
+                                */
+                               return 1;
                        fprintf(stderr, Name ": Cannot set new_offset for %s\n",
                                dn);
                        break;
@@ -2358,6 +2362,11 @@ static int raid10_reshape(char *container, int fd, char *devname,
        }
        err = set_new_data_offset(sra, st, devname, info->delta_disks, data_offset,
                                  min);
+       if (err == 1) {
+               pr_err("Cannot set new_data_offset: RAID10 reshape not\n");
+               cont_err("supported on this kernel\n");
+               err = -1;
+       }
        if (err < 0)
                goto release;