dm raid: support to change bitmap region size

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index e4c41232107f..7df450877423 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -217,6 +217,7 @@ struct raid_set {
         int delta_disks;
         int data_offset;
         int raid10_copies;
+        int requested_bitmap_chunk_sectors;
 
         struct mddev md;
         struct raid_type *raid_type;
@@ -1277,6 +1278,7 @@ static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
                         }
 
                         region_size = value;
+                        rs->requested_bitmap_chunk_sectors = value;
                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {
                         if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) {
                                 rs->ti->error = "Only one raid10_copies argument pair allowed";
@@ -3401,6 +3403,15 @@ static int raid_preresume(struct dm_target *ti)
         if (r)
                 return r;
 
+        /* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) */
+        if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) &&
+            mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)) {
+                r = bitmap_resize(mddev->bitmap, mddev->dev_sectors,
+                                  to_bytes(rs->requested_bitmap_chunk_sectors), 0);
+                if (r)
+                        DMERR("Failed to resize bitmap");
+        }
+
         /* Check for any resize/reshape on @rs and adjust/initiate */
         /* Be prepared for mddev_resume() in raid_resume() */
         set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);