block: introduce struct rq_map_data to use reserved pages
This patch introduces struct rq_map_data to enable bio_copy_use_iov()
use reserved pages.
Currently, bio_copy_user_iov allocates bounce pages but
drivers/scsi/sg.c wants to allocate pages by itself and use
them. struct rq_map_data can be used to pass allocated pages to
bio_copy_user_iov.
The current users of bio_copy_user_iov simply passes NULL (they don't
want to use pre-allocated pages).
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index f49d6a1..c34272a 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -314,11 +314,11 @@
goto out;
}
- ret = blk_rq_map_user_iov(q, rq, iov, hdr->iovec_count,
+ ret = blk_rq_map_user_iov(q, rq, NULL, iov, hdr->iovec_count,
hdr->dxfer_len, GFP_KERNEL);
kfree(iov);
} else if (hdr->dxfer_len)
- ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len,
+ ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
GFP_KERNEL);
if (ret)