diff --git a/block/blk-core.c b/block/blk-core.c
index c013ca22eb67..775c8516abf5 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -127,6 +127,7 @@ void rq_init(struct request_queue *q, struct request *rq)
 	rq->nr_hw_segments = 0;
 	rq->ioprio = 0;
 	rq->special = NULL;
+	rq->raw_data_len = 0;
 	rq->buffer = NULL;
 	rq->tag = -1;
 	rq->errors = 0;
@@ -2015,6 +2016,7 @@ void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
 	rq->hard_cur_sectors = rq->current_nr_sectors;
 	rq->hard_nr_sectors = rq->nr_sectors = bio_sectors(bio);
 	rq->buffer = bio_data(bio);
+	rq->raw_data_len = bio->bi_size;
 	rq->data_len = bio->bi_size;
 
 	rq->bio = rq->biotail = bio;
diff --git a/block/blk-map.c b/block/blk-map.c
index a7cf63ccb5cf..09f7fd0bcb73 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -19,6 +19,7 @@ int blk_rq_append_bio(struct request_queue *q, struct request *rq,
 		rq->biotail->bi_next = bio;
 		rq->biotail = bio;
 
+		rq->raw_data_len += bio->bi_size;
 		rq->data_len += bio->bi_size;
 	}
 	return 0;
@@ -154,6 +155,7 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
 
 		bio->bi_io_vec[bio->bi_vcnt - 1].bv_len += pad_len;
 		bio->bi_size += pad_len;
+		rq->data_len += pad_len;
 	}
 
 	rq->buffer = rq->data = NULL;
diff --git a/block/blk-merge.c b/block/blk-merge.c
index d3b84bbb776a..39f2e077a014 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -228,6 +228,7 @@ new_segment:
 			    ((unsigned long)q->dma_drain_buffer) &
 			    (PAGE_SIZE - 1));
 		nsegs++;
+		rq->data_len += q->dma_drain_size;
 	}
 
 	if (sg)
diff --git a/block/bsg.c b/block/bsg.c
index 8917c5174dc2..7f3c09549e4b 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -437,14 +437,14 @@ static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr,
 	}
 
 	if (rq->next_rq) {
-		hdr->dout_resid = rq->data_len;
-		hdr->din_resid = rq->next_rq->data_len;
+		hdr->dout_resid = rq->raw_data_len;
+		hdr->din_resid = rq->next_rq->raw_data_len;
 		blk_rq_unmap_user(bidi_bio);
 		blk_put_request(rq->next_rq);
 	} else if (rq_data_dir(rq) == READ)
-		hdr->din_resid = rq->data_len;
+		hdr->din_resid = rq->raw_data_len;
 	else
-		hdr->dout_resid = rq->data_len;
+		hdr->dout_resid = rq->raw_data_len;
 
 	/*
 	 * If the request generated a negative error number, return it
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index 9675b34638d4..e993cac4911d 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->data_len;
+	hdr->resid = rq->raw_data_len;
 	hdr->sb_len_wr = 0;
 
 	if (rq->sense_len && hdr->sbp) {
@@ -528,6 +528,7 @@ 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->timeout = BLK_DEFAULT_SG_TIMEOUT;
 	memset(rq->cmd, 0, sizeof(rq->cmd));
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 135c1d054701..ba21d97d1855 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1014,10 +1014,6 @@ static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb,
 	}
 
 	req->buffer = NULL;
-	if (blk_pc_request(req))
-		sdb->length = req->data_len;
-	else
-		sdb->length = req->nr_sectors << 9;
 
 	/* 
 	 * Next, walk the list, and fill in the addresses and sizes of
@@ -1026,6 +1022,10 @@ static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb,
 	count = blk_rq_map_sg(req->q, req, sdb->table.sgl);
 	BUG_ON(count > sdb->table.nents);
 	sdb->table.nents = count;
+	if (blk_pc_request(req))
+		sdb->length = req->data_len;
+	else
+		sdb->length = req->nr_sectors << 9;
 	return BLKPREP_OK;
 }
 
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index e1888cc5b8ae..f1fe9fbf1c0e 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -216,6 +216,7 @@ struct request {
 	unsigned int cmd_len;
 	unsigned char cmd[BLK_MAX_CDB];
 
+	unsigned int raw_data_len;
 	unsigned int data_len;
 	unsigned int sense_len;
 	void *data;