imsm: FIX: Add volume size expand support to imsm_analyze_change()

Patch adds ability to function imsm_analyze_change() for:
1. Detect size change request for volume operation.
2. Check and correct size for change.
3. Set new change kind to CH_ARRAY_SIZE

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 5f865396e21d74dbcc51c1ed6f4e2eb89a6c72a5..2e6a899199876d23eb4013f783fc8ed03013dd93 100644 (file)
--- a/super-intel.c
+++ b/super-intel.c
@@ -405,6 +405,7 @@ struct extent {
 enum imsm_reshape_type {
        CH_TAKEOVER,
        CH_MIGRATION,
+       CH_ARRAY_SIZE,
 };
 
 /* definition of messages passed to imsm_process_update */
@@ -9726,6 +9727,10 @@ enum imsm_reshape_type imsm_analyze_change(struct supertype *st,
        int devNumChange = 0;
        /* imsm compatible layout value for array geometry verification */
        int imsm_layout = -1;
+       int data_disks;
+       struct imsm_dev *dev;
+       struct intel_super *super;
+       long long current_size;
 
        getinfo_super_imsm_volume(st, &info, NULL);
        if ((geo->level != info.array.level) &&
@@ -9807,6 +9812,47 @@ enum imsm_reshape_type imsm_analyze_change(struct supertype *st,
                geo->chunksize = info.array.chunk_size;
 
        chunk = geo->chunksize / 1024;
+
+       super = st->sb;
+       dev = get_imsm_dev(super, super->current_vol);
+       data_disks = imsm_num_data_members(dev , MAP_0);
+       /* compute current size in K per disk member
+        */
+       current_size = info.custom_array_size / 2 / data_disks;
+
+       if ((current_size != geo->size) && (geo->size > 0)) {
+               if (change != -1) {
+                       fprintf(stderr,
+                               Name " Error. Size change should be the only "
+                               "one at a time.\n");
+                       change = -1;
+                       goto analyse_change_exit;
+               }
+               if ((super->current_vol + 1) != super->anchor->num_raid_devs) {
+                       fprintf(stderr,
+                               Name " Error. The last volume in container "
+                               "can be expanded only (%i/%i).\n",
+                               super->current_vol, st->devnum);
+                       goto analyse_change_exit;
+               }
+               geo->size *= 2;
+               /* round size due to metadata compatibility
+                */
+               geo->size = (geo->size >> SECT_PER_MB_SHIFT)
+                           << SECT_PER_MB_SHIFT;
+               dprintf("Prepare update for size change to %llu\n", geo->size );
+               if (current_size >= geo->size) {
+                       fprintf(stderr,
+                               Name " Error. Size expanssion is supported only"
+                               " (current size is %llu, requested size "
+                               "/rounded/ is %llu).\n",
+                               current_size, geo->size);
+                       goto analyse_change_exit;
+               }
+               geo->size *= data_disks;
+               geo->raid_disks = dev->vol.map->num_members;
+               change = CH_ARRAY_SIZE;
+       }
        if (!validate_geometry_imsm(st,
                                    geo->level,
                                    imsm_layout,
@@ -9976,6 +10022,11 @@ static int imsm_reshape_super(struct supertype *st, long long size, int level,
                                free(u);
                }
                break;
+               case CH_ARRAY_SIZE: {
+                       /* ToDo: Prepare metadata update here
+                        */
+               }
+               break;
                default:
                        ret_val = 1;
                }