[MTD] Allow variable block sizes in mtd_blkdevs

Currently, mtd_blkdevs enforces a block size of 512, even if the drivers
can seemingly request a different size. This patch fixes mtd_blkdevs so
block sizes other than 512 work correctly.

Signed-off-by: Richard Purdie <rpurdie@openedhand.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 9 insertions, 6 deletions

diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c
index 178b53b56be9..b5d62cb357da 100644
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -42,19 +42,20 @@ static int do_blktrans_request(struct mtd_blktrans_ops *tr,
         unsigned long block, nsect;
         char *buf;
 
-        block = req->sector;
-        nsect = req->current_nr_sectors;
+        block = req->sector << 9 >> tr->blkshift;
+        nsect = req->current_nr_sectors << 9 >> tr->blkshift;
+
         buf = req->buffer;
 
         if (!blk_fs_request(req))
                 return 0;
 
-        if (block + nsect > get_capacity(req->rq_disk))
+        if (req->sector + req->current_nr_sectors > get_capacity(req->rq_disk))
                 return 0;
 
         switch(rq_data_dir(req)) {
         case READ:
-                for (; nsect > 0; nsect--, block++, buf += 512)
+                for (; nsect > 0; nsect--, block++, buf += tr->blksize)
                         if (tr->readsect(dev, block, buf))
                                 return 0;
                 return 1;
@@ -63,7 +64,7 @@ static int do_blktrans_request(struct mtd_blktrans_ops *tr,
                 if (!tr->writesect)
                         return 0;
 
-                for (; nsect > 0; nsect--, block++, buf += 512)
+                for (; nsect > 0; nsect--, block++, buf += tr->blksize)
                         if (tr->writesect(dev, block, buf))
                                 return 0;
                 return 1;
@@ -297,7 +298,7 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 
         /* 2.5 has capacity in units of 512 bytes while still
            having BLOCK_SIZE_BITS set to 10. Just to keep us amused. */
-        set_capacity(gd, (new->size * new->blksize) >> 9);
+        set_capacity(gd, (new->size * tr->blksize) >> 9);
 
         gd->private_data = new;
         new->blkcore_priv = gd;
@@ -401,6 +402,8 @@ int register_mtd_blktrans(struct mtd_blktrans_ops *tr)
         }
 
         tr->blkcore_priv->rq->queuedata = tr;
+        blk_queue_hardsect_size(tr->blkcore_priv->rq, tr->blksize);
+        tr->blkshift = ffs(tr->blksize) - 1;
 
         ret = kernel_thread(mtd_blktrans_thread, tr, CLONE_KERNEL);
         if (ret < 0) {