[PATCH] md: remove arbitrary limit on chunk size

The largest chunk size the code can support without substantial surgery is
2^30 bytes, so make that the limit instead of an arbitrary 4Meg.  Some day,
the 'chunksize' should change to a sector-shift instead of a byte-count.  Then
no limit would be needed.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

4 files changed, 7 insertions, 6 deletions

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 1440935414e6..affeaefd4033 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -2050,7 +2050,7 @@ static int run(mddev_t *mddev)
          * maybe...
          */
         {
-                int stripe = conf->raid_disks * mddev->chunk_size / PAGE_SIZE;
+                int stripe = conf->raid_disks * (mddev->chunk_size / PAGE_SIZE);
                 stripe /= conf->near_copies;
                 if (mddev->queue->backing_dev_info.ra_pages < 2* stripe)
                         mddev->queue->backing_dev_info.ra_pages = 2* stripe;
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 31843604049c..122e64e557b1 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -2382,8 +2382,8 @@ static int run(mddev_t *mddev)
          * 2 * (n-1) * chunksize where 'n' is the number of raid devices
          */
         {
-                int stripe = (mddev->raid_disks-1) * mddev->chunk_size
-                        / PAGE_SIZE;
+                int stripe = (mddev->raid_disks-1) *
+                        (mddev->chunk_size / PAGE_SIZE);
                 if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe)
                         mddev->queue->backing_dev_info.ra_pages = 2 * stripe;
         }
diff --git a/drivers/md/raid6main.c b/drivers/md/raid6main.c
index bc69355e0100..e53d2d96ea3a 100644
--- a/drivers/md/raid6main.c
+++ b/drivers/md/raid6main.c
@@ -2135,8 +2135,8 @@ static int run(mddev_t *mddev)
          * 2 * (n-2) * chunksize where 'n' is the number of raid devices
          */
         {
-                int stripe = (mddev->raid_disks-2) * mddev->chunk_size
-                        / PAGE_SIZE;
+                int stripe = (mddev->raid_disks-2) *
+                        (mddev->chunk_size / PAGE_SIZE);
                 if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe)
                         mddev->queue->backing_dev_info.ra_pages = 2 * stripe;
         }
diff --git a/include/linux/raid/md_k.h b/include/linux/raid/md_k.h
index e2df61f5b09a..db2ca2d9066e 100644
--- a/include/linux/raid/md_k.h
+++ b/include/linux/raid/md_k.h
@@ -40,7 +40,8 @@ typedef struct mdk_rdev_s mdk_rdev_t;
  * options passed in raidrun:
  */
 
-#define MAX_CHUNK_SIZE (4096*1024)
+/* Currently this must fix in an 'int' */
+#define MAX_CHUNK_SIZE (1<<30)
 
 /*
  * MD's 'extended' device