dm raid: restructure parse_raid_params

In preparation for RAID10 addition to dm-raid, we change an 'if' conditional
to a 'switch' conditional to make it easier to see what is being checked for
each RAID type.

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

1 files changed, 20 insertions, 5 deletions

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 858a8b70811c..1717ed33dd7f 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -430,13 +430,28 @@ static int parse_raid_params(struct raid_set *rs, char **argv,
 
                 if (!strcasecmp(key, "rebuild")) {
                         rebuild_cnt++;
-                        if (((rs->raid_type->level != 1) &&
-                             (rebuild_cnt > rs->raid_type->parity_devs)) ||
-                            ((rs->raid_type->level == 1) &&
-                             (rebuild_cnt > (rs->md.raid_disks - 1)))) {
-                                rs->ti->error = "Too many rebuild devices specified for given RAID type";
+
+                        switch (rs->raid_type->level) {
+                        case 1:
+                                if (rebuild_cnt >= rs->md.raid_disks) {
+                                        rs->ti->error = "Too many rebuild devices specified";
+                                        return -EINVAL;
+                                }
+                                break;
+                        case 4:
+                        case 5:
+                        case 6:
+                                if (rebuild_cnt > rs->raid_type->parity_devs) {
+                                        rs->ti->error = "Too many rebuild devices specified for given RAID type";
+                                        return -EINVAL;
+                                }
+                                break;
+                        default:
+                                DMERR("The rebuild parameter is not supported for %s", rs->raid_type->name);
+                                rs->ti->error = "Rebuild not supported for this RAID type";
                                 return -EINVAL;
                         }
+
                         if (value > rs->md.raid_disks) {
                                 rs->ti->error = "Invalid rebuild index given";
                                 return -EINVAL;