block: restore the meaning of rq->data_len to the true data length

The meaning of rq->data_len was changed to the length of an allocated
buffer from the true data length. It breaks SG_IO friends and
bsg. This patch restores the meaning of rq->data_len to the true data
length and adds rq->extra_len to store an extended length (due to
drain buffer and padding).

This patch also removes the code to update bio in blk_rq_map_user
introduced by the commit 40b01b9bbdf51ae543a04744283bf2d56c4a6afa.
The commit adjusts bio according to memory alignment
(queue_dma_alignment). However, memory alignment is NOT padding
alignment. This adjustment also breaks SG_IO friends and bsg. Padding
alignment needs to be fixed in a proper way (by a separate patch).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>

1 files changed, 2 insertions, 2 deletions

diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index e993cac4911d..a2c3a936ebf9 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -266,7 +266,7 @@ static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
         hdr->info = 0;
         if (hdr->masked_status || hdr->host_status || hdr->driver_status)
                 hdr->info |= SG_INFO_CHECK;
-        hdr->resid = rq->raw_data_len;
+        hdr->resid = rq->data_len;
         hdr->sb_len_wr = 0;
 
         if (rq->sense_len && hdr->sbp) {
@@ -528,8 +528,8 @@ static int __blk_send_generic(struct request_queue *q, struct gendisk *bd_disk,
         rq = blk_get_request(q, WRITE, __GFP_WAIT);
         rq->cmd_type = REQ_TYPE_BLOCK_PC;
         rq->data = NULL;
-        rq->raw_data_len = 0;
         rq->data_len = 0;
+        rq->extra_len = 0;
         rq->timeout = BLK_DEFAULT_SG_TIMEOUT;
         memset(rq->cmd, 0, sizeof(rq->cmd));
         rq->cmd[0] = cmd;