imsm: Add support for general migration

Internal IMSM procedures need to support the General Migration.
It is used during operations like:
- Online Capacity Expansion,
- migration initialization,
- finishing migration,
- apply changes to raid disks etc.

Signed-off-by: Adam Kwolek <adam.kwolek@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/super-intel.c b/super-intel.c
index 9b4ad19a6adce9b9bd011dc61c5e219236e9d54e..46d216ed8bf20c75040bb1343116f3cd11bf7eb4 100644 (file)
--- a/super-intel.c
+++ b/super-intel.c
@@ -2183,7 +2183,8 @@ static void migrate(struct imsm_dev *dev, __u8 to_state, int migr_type)
 
        /* duplicate and then set the target end state in map[0] */
        memcpy(dest, src, sizeof_imsm_map(src));
-       if (migr_type == MIGR_REBUILD) {
+       if ((migr_type == MIGR_REBUILD) ||
+           (migr_type ==  MIGR_GEN_MIGR)) {
                __u32 ord;
                int i;
 
@@ -2200,18 +2201,26 @@ static void end_migration(struct imsm_dev *dev, __u8 map_state)
 {
        struct imsm_map *map = get_imsm_map(dev, 0);
        struct imsm_map *prev = get_imsm_map(dev, dev->vol.migr_state);
-       int i;
+       int i, j;
 
        /* merge any IMSM_ORD_REBUILD bits that were not successfully
         * completed in the last migration.
         *
-        * FIXME add support for online capacity expansion and
-        * raid-level-migration
+        * FIXME add support for raid-level-migration
         */
        for (i = 0; i < prev->num_members; i++)
-               map->disk_ord_tbl[i] |= prev->disk_ord_tbl[i];
+               for (j = 0; j < map->num_members; j++)
+                       /* during online capacity expansion
+                        * disks position can be changed if takeover is used
+                        */
+                       if (ord_to_idx(map->disk_ord_tbl[j]) ==
+                           ord_to_idx(prev->disk_ord_tbl[i])) {
+                               map->disk_ord_tbl[j] |= prev->disk_ord_tbl[i];
+                               break;
+                       }
 
        dev->vol.migr_state = 0;
+       dev->vol.migr_type = 0;
        dev->vol.curr_migr_unit = 0;
        map->map_state = map_state;
 }
@@ -4323,6 +4332,17 @@ static int update_subarray_imsm(struct supertype *st, char *subarray,
 }
 #endif /* MDASSEMBLE */
 
+static int is_gen_migration(struct imsm_dev *dev)
+{
+       if (!dev->vol.migr_state)
+               return 0;
+
+       if (migr_type(dev) == MIGR_GEN_MIGR)
+               return 1;
+
+       return 0;
+}
+
 static int is_rebuilding(struct imsm_dev *dev)
 {
        struct imsm_map *migr_map;
@@ -4413,8 +4433,7 @@ static struct mdinfo *container_content_imsm(struct supertype *st, char *subarra
                 * unsupported migration
                 */
                if (dev->vol.migr_state &&
-                   (migr_type(dev) == MIGR_GEN_MIGR ||
-                    migr_type(dev) == MIGR_STATE_CHANGE)) {
+                   (migr_type(dev) == MIGR_STATE_CHANGE)) {
                        fprintf(stderr, Name ": cannot assemble volume '%.16s':"
                                " unsupported migration in progress\n",
                                dev->volume);
@@ -4697,6 +4716,8 @@ static void handle_missing(struct intel_super *super, struct imsm_dev *dev)
        super->updates_pending++;
 }
 
+static void imsm_set_disk(struct active_array *a, int n, int state);
+
 /* Handle dirty -> clean transititions and resync.  Degraded and rebuild
  * states are handled in imsm_set_disk() with one exception, when a
  * resync is stopped due to a new failure this routine will set the
@@ -4772,6 +4793,16 @@ static int imsm_set_array_state(struct active_array *a, int consistent)
                        dev->vol.dirty = 1;
                super->updates_pending++;
        }
+
+       /* finalize online capacity expansion/reshape */
+       if ((a->curr_action != reshape) &&
+           (a->prev_action == reshape)) {
+               struct mdinfo *mdi;
+
+               for (mdi = a->info.devs; mdi; mdi = mdi->next)
+                       imsm_set_disk(a, mdi->disk.raid_disk, mdi->curr_state);
+       }
+
        return consistent;
 }
 
@@ -4835,6 +4866,23 @@ static void imsm_set_disk(struct active_array *a, int n, int state)
                end_migration(dev, map_state);
                super->updates_pending++;
                a->last_checkpoint = 0;
+       } else if (is_gen_migration(dev)) {
+               dprintf("imsm: Detected General Migration in state: ");
+               if (map_state == IMSM_T_STATE_NORMAL) {
+                       end_migration(dev, map_state);
+                       map = get_imsm_map(dev, 0);
+                       map->failed_disk_num = ~0;
+                       dprintf("normal\n");
+               } else {
+                       if (map_state == IMSM_T_STATE_DEGRADED) {
+                               printf("degraded\n");
+                               end_migration(dev, map_state);
+                       } else {
+                               dprintf("failed\n");
+                       }
+                       map->map_state = map_state;
+               }
+               super->updates_pending++;
        }
 }