Grow: fix problem with reshaping RAID4 to RAID0.

As 'layout' doesn't map neatly from RAID4 to RAID5, we need to
set it correctly for RAID4.
Also, when no reshape is needed we should set re->level to the final
desired level.

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

diff --git a/Grow.c b/Grow.c
index 1ab6f4064a37a9a6092a7dd04acdeb8d7d193305..2cc93578c9461c2dfc8c0eeda907be235937bde1 100644 (file)
--- a/Grow.c
+++ b/Grow.c
@@ -1321,6 +1321,7 @@ char *analyse_change(struct mdinfo *info, struct reshape *re)
 
                switch (re->level) {
                case 4:
+                       re->before.layout = 0;
                        re->after.layout = 0;
                        break;
                case 5:
@@ -1336,6 +1337,7 @@ char *analyse_change(struct mdinfo *info, struct reshape *re)
 
                switch (re->level) {
                case 4:
+                       re->before.layout = 0;
                        re->after.layout = 0;
                        break;
                case 5:
@@ -1428,12 +1430,14 @@ char *analyse_change(struct mdinfo *info, struct reshape *re)
        if (re->after.data_disks == re->before.data_disks &&
            re->after.layout == re->before.layout &&
            info->new_chunk == info->array.chunk_size) {
-               /* Nothing to change */
+               /* Nothing to change, can change level immediately. */
+               re->level = info->new_level;
                re->backup_blocks = 0;
                return NULL;
        }
        if (re->after.data_disks == 1 && re->before.data_disks == 1) {
                /* chunk and layout changes make no difference */
+               re->level = info->new_level;
                re->backup_blocks = 0;
                return NULL;
        }