1 files changed, 22 insertions, 12 deletions

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 80ec9a6d8a18..f7fb2b87ad89 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3738,6 +3738,7 @@ static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped
         int dd_idx;
         sector_t writepos, safepos, gap;
         sector_t stripe_addr;
+        int reshape_sectors;
 
         if (sector_nr == 0) {
                 /* If restarting in the middle, skip the initial sectors */
@@ -3755,6 +3756,15 @@ static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped
                 }
         }
 
+        /* We need to process a full chunk at a time.
+         * If old and new chunk sizes differ, we need to process the
+         * largest of these
+         */
+        if (mddev->new_chunk > mddev->chunk_size)
+                reshape_sectors = mddev->new_chunk / 512;
+        else
+                reshape_sectors = mddev->chunk_size / 512;
+
         /* we update the metadata when there is more than 3Meg
          * in the block range (that is rather arbitrary, should
          * probably be time based) or when the data about to be
@@ -3768,12 +3778,12 @@ static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped
         safepos = conf->reshape_safe;
         sector_div(safepos, data_disks);
         if (mddev->delta_disks < 0) {
-                writepos -= conf->chunk_size/512;
-                safepos += conf->chunk_size/512;
+                writepos -= reshape_sectors;
+                safepos += reshape_sectors;
                 gap = conf->reshape_safe - conf->reshape_progress;
         } else {
-                writepos += conf->chunk_size/512;
-                safepos -= conf->chunk_size/512;
+                writepos += reshape_sectors;
+                safepos -= reshape_sectors;
                 gap = conf->reshape_progress - conf->reshape_safe;
         }
 
@@ -3799,14 +3809,14 @@ static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped
                 BUG_ON(conf->reshape_progress == 0);
                 stripe_addr = writepos;
                 BUG_ON((mddev->dev_sectors &
-                        ~((sector_t)conf->chunk_size / 512 - 1))
-                       - (conf->chunk_size / 512) - stripe_addr
+                        ~((sector_t)reshape_sectors - 1))
+                       - reshape_sectors - stripe_addr
                        != sector_nr);
         } else {
-                BUG_ON(writepos != sector_nr + conf->chunk_size / 512);
+                BUG_ON(writepos != sector_nr + reshape_sectors);
                 stripe_addr = sector_nr;
         }
-        for (i=0; i < conf->chunk_size/512; i+= STRIPE_SECTORS) {
+        for (i = 0; i < reshape_sectors; i += STRIPE_SECTORS) {
                 int j;
                 int skipped = 0;
                 sh = get_active_stripe(conf, stripe_addr+i, 0, 0);
@@ -3839,9 +3849,9 @@ static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped
         }
         spin_lock_irq(&conf->device_lock);
         if (mddev->delta_disks < 0)
-                conf->reshape_progress -= i * new_data_disks;
+                conf->reshape_progress -= reshape_sectors * new_data_disks;
         else
-                conf->reshape_progress += i * new_data_disks;
+                conf->reshape_progress += reshape_sectors * new_data_disks;
         spin_unlock_irq(&conf->device_lock);
         /* Ok, those stripe are ready. We can start scheduling
          * reads on the source stripes.
@@ -3867,7 +3877,7 @@ static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped
         /* If this takes us to the resync_max point where we have to pause,
          * then we need to write out the superblock.
          */
-        sector_nr += conf->chunk_size>>9;
+        sector_nr += reshape_sectors;
         if (sector_nr >= mddev->resync_max) {
                 /* Cannot proceed until we've updated the superblock... */
                 wait_event(conf->wait_for_overlap,
@@ -3883,7 +3893,7 @@ static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped
                 spin_unlock_irq(&conf->device_lock);
                 wake_up(&conf->wait_for_overlap);
         }
-        return conf->chunk_size>>9;
+        return reshape_sectors;
 }
 
 /* FIXME go_faster isn't used */