super1: fix sb->max_dev when adding a new disk in linear array

The value of sb->max_dev will always be increased by 1 when adding
a new disk in linear array. It causes an inconsistence between each
disk in the array and the "Array State" value of "mdadm --examine DISK"
is wrong. For example, when adding the first new disk into linear array
it will be:

Array State : RAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
('A' == active, '.' == missing, 'R' == replacing)

Adding the second disk into linear array it will be

Array State : .AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
('A' == active, '.' == missing, 'R' == replacing)

Signed-off-by: Lidong Zhong <lzhong@suse.com>
Signed-off-by: Jes Sorensen <jsorensen@fb.com>

diff --git a/super1.c b/super1.c
index 2fcb81479536ef95921e0cc6e95eebb93e2abbc4..86ec850d03bd022d57b4494479312e7ef4420a89 100644 (file)
--- a/super1.c
+++ b/super1.c
@@ -1267,8 +1267,9 @@ static int update_super1(struct supertype *st, struct mdinfo *info,
                                break;
                sb->dev_number = __cpu_to_le32(i);
                info->disk.number = i;
-               if (max >= __le32_to_cpu(sb->max_dev))
+               if (i >= max) {
                        sb->max_dev = __cpu_to_le32(max+1);
+               }
 
                random_uuid(sb->device_uuid);
 
@@ -1293,7 +1294,11 @@ static int update_super1(struct supertype *st, struct mdinfo *info,
                        }
                }
        } else if (strcmp(update, "linear-grow-update") == 0) {
+               int max = __le32_to_cpu(sb->max_dev);
                sb->raid_disks = __cpu_to_le32(info->array.raid_disks);
+               if (info->array.raid_disks > max) {
+                       sb->max_dev = __cpu_to_le32(max+1);
+               }
                sb->dev_roles[info->disk.number] =
                        __cpu_to_le16(info->disk.raid_disk);
        } else if (strcmp(update, "resync") == 0) {