4 files changed, 28 insertions, 13 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 9e2336fbbd31..86adf4ac46cf 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -6153,11 +6153,7 @@ static int update_size(struct mddev *mddev, sector_t num_sectors)
          */
         if (mddev->sync_thread)
                 return -EBUSY;
-        if (mddev->bitmap)
-                /* Sorry, cannot grow a bitmap yet, just remove it,
-                 * grow, and re-add.
-                 */
-                return -EBUSY;
+
         rdev_for_each(rdev, mddev) {
                 sector_t avail = rdev->sectors;
 
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 22cfc6660b18..8e717bd518e7 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -2752,9 +2752,16 @@ static int raid1_resize(struct mddev *mddev, sector_t sectors)
          * any io in the removed space completes, but it hardly seems
          * worth it.
          */
-        md_set_array_sectors(mddev, raid1_size(mddev, sectors, 0));
-        if (mddev->array_sectors > raid1_size(mddev, sectors, 0))
+        sector_t newsize = raid1_size(mddev, sectors, 0);
+        if (mddev->external_size &&
+            mddev->array_sectors > newsize)
                 return -EINVAL;
+        if (mddev->bitmap) {
+                int ret = bitmap_resize(mddev->bitmap, newsize, 0, 0);
+                if (ret)
+                        return ret;
+        }
+        md_set_array_sectors(mddev, newsize);
         set_capacity(mddev->gendisk, mddev->array_sectors);
         revalidate_disk(mddev->gendisk);
         if (sectors > mddev->dev_sectors &&
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index fb9062b5022c..8fe3aa469987 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -3678,9 +3678,15 @@ static int raid10_resize(struct mddev *mddev, sector_t sectors)
 
         oldsize = raid10_size(mddev, 0, 0);
         size = raid10_size(mddev, sectors, 0);
-        md_set_array_sectors(mddev, size);
-        if (mddev->array_sectors > size)
+        if (mddev->external_size &&
+            mddev->array_sectors > size)
                 return -EINVAL;
+        if (mddev->bitmap) {
+                int ret = bitmap_resize(mddev->bitmap, size, 0, 0);
+                if (ret)
+                        return ret;
+        }
+        md_set_array_sectors(mddev, size);
         set_capacity(mddev->gendisk, mddev->array_sectors);
         revalidate_disk(mddev->gendisk);
         if (sectors > mddev->dev_sectors &&
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 7bfd59b313d7..eab6168bb7f4 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -5503,12 +5503,18 @@ static int raid5_resize(struct mddev *mddev, sector_t sectors)
          * any io in the removed space completes, but it hardly seems
          * worth it.
          */
+        sector_t newsize;
         sectors &= ~((sector_t)mddev->chunk_sectors - 1);
-        md_set_array_sectors(mddev, raid5_size(mddev, sectors,
-                                               mddev->raid_disks));
-        if (mddev->array_sectors >
-            raid5_size(mddev, sectors, mddev->raid_disks))
+        newsize = raid5_size(mddev, sectors, mddev->raid_disks);
+        if (mddev->external_size &&
+            mddev->array_sectors > newsize)
                 return -EINVAL;
+        if (mddev->bitmap) {
+                int ret = bitmap_resize(mddev->bitmap, sectors, 0, 0);
+                if (ret)
+                        return ret;
+        }
+        md_set_array_sectors(mddev, newsize);
         set_capacity(mddev->gendisk, mddev->array_sectors);
         revalidate_disk(mddev->gendisk);
         if (sectors > mddev->dev_sectors &&