md: support bitmaps on RAID10 arrays larger then 2 terabytes

.. and other arrays with components larger than 2 terabytes.

We use a "long" rather than a "sector_t" in part of the bitmap
size calculations, which is sad.

Reported-by: "Mario 'BitKoenig' Holbe" <Mario.Holbe@TU-Ilmenau.DE>
Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index e4510c976b348cc4d1445ed09ed73b4c3f9113a4..1fb91edc7de26ac27f5804e9a99f45a9be6aab31 100644 (file)
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -1590,7 +1590,7 @@ void bitmap_destroy(mddev_t *mddev)
 int bitmap_create(mddev_t *mddev)
 {
        struct bitmap *bitmap;
-       unsigned long blocks = mddev->resync_max_sectors;
+       sector_t blocks = mddev->resync_max_sectors;
        unsigned long chunks;
        unsigned long pages;
        struct file *file = mddev->bitmap_file;
@@ -1632,8 +1632,8 @@ int bitmap_create(mddev_t *mddev)
        bitmap->chunkshift = ffz(~bitmap->chunksize);
 
        /* now that chunksize and chunkshift are set, we can use these macros */
-       chunks = (blocks + CHUNK_BLOCK_RATIO(bitmap) - 1) /
-                       CHUNK_BLOCK_RATIO(bitmap);
+       chunks = (blocks + CHUNK_BLOCK_RATIO(bitmap) - 1) >>
+                       CHUNK_BLOCK_SHIFT(bitmap);
        pages = (chunks + PAGE_COUNTER_RATIO - 1) / PAGE_COUNTER_RATIO;
 
        BUG_ON(!pages);