Manual merge from Andrew Morton: don't assume read-ahead for md

diff --git a/drivers/md/md.c b/drivers/md/md.c
index c2322e471116fa3aa5f1d0b6a0b687da3b123ad4..b6a021b38d256663d1b7f45a9551c7e859fa2676 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1520,7 +1520,6 @@ static int device_size_calculation(mddev_t * mddev)
        mdp_super_t *sb = mddev->sb;
        struct list_head *tmp;
        mdk_rdev_t *rdev;
-       unsigned long *ra_pages;
 
        /*
         * Do device size calculation. Bail out if too small.
@@ -1578,9 +1577,6 @@ static int device_size_calculation(mddev_t * mddev)
                md_size[mdidx(mddev)] = sb->size * data_disks;
 
        readahead = (VM_MAX_READAHEAD * 1024) / PAGE_SIZE;
-       ra_pages = blk_get_ra_pages(rdev->bdev);
-       if (ra_pages)
-               readahead = (*ra_pages * PAGE_CACHE_SIZE) / PAGE_SIZE;
        if (!sb->level || (sb->level == 4) || (sb->level == 5)) {
                readahead = (mddev->sb->chunk_size>>PAGE_SHIFT) * 4 * data_disks;
                if (readahead < data_disks * (MAX_SECTORS>>(PAGE_SHIFT-9))*2)