[PATCH 06/17] blk-map/bio: use struct iovec instead of sg_iovec

[Tejun Heo <tj@kernel.org>]

Impact: cleanup

blk-map and bio use sg_iovec for addr-len segments although there
isn't anything sg-specific about the API.  This is mostly due to
historical reasons.  sg_iovec is by definition identical to iovec.
Use iovec instead.  This removes bogus dependency on scsi sg and will
allow use of iovec helpers.

Signed-off-by: Tejun Heo <tj@kernel.org>
---
 block/blk-map.c        |    5 ++---
 block/scsi_ioctl.c     |    8 +++-----
 fs/bio.c               |   23 +++++++++++------------
 include/linux/bio.h    |    6 +++---
 include/linux/blkdev.h |    8 ++++----
 5 files changed, 23 insertions(+), 27 deletions(-)

diff --git a/block/blk-map.c b/block/blk-map.c
index 29aa60d..4f0221a 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -5,7 +5,6 @@
 #include <linux/module.h>
 #include <linux/bio.h>
 #include <linux/blkdev.h>
-#include <scsi/sg.h>		/* for struct sg_iovec */
 
 #include "blk.h"
 
@@ -64,7 +63,7 @@ static int __blk_rq_unmap_user(struct bio *bio)
  *    unmapping.
  */
 int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
-			struct rq_map_data *map_data, struct sg_iovec *iov,
+			struct rq_map_data *map_data, struct iovec *iov,
 			int iov_count, unsigned int len, gfp_t gfp_mask)
 {
 	struct bio *bio = ERR_PTR(-EINVAL);
@@ -130,7 +129,7 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
 		    struct rq_map_data *map_data, void __user *ubuf,
 		    unsigned long len, gfp_t gfp_mask)
 {
-	struct sg_iovec iov;
+	struct iovec iov;
 
 	iov.iov_base = ubuf;
 	iov.iov_len = len;
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index c8e8868..73cfd91 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -289,7 +289,7 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 	if (hdr->iovec_count) {
 		const int size = sizeof(struct sg_iovec) * hdr->iovec_count;
 		size_t iov_data_len;
-		struct sg_iovec *iov;
+		struct iovec *iov;
 
 		iov = kmalloc(size, GFP_KERNEL);
 		if (!iov) {
@@ -304,11 +304,9 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 		}
 
 		/* SG_IO howto says that the shorter of the two wins */
-		iov_data_len = iov_length((struct iovec *)iov,
-					  hdr->iovec_count);
+		iov_data_len = iov_length(iov, hdr->iovec_count);
 		if (hdr->dxfer_len < iov_data_len) {
-			hdr->iovec_count = iov_shorten((struct iovec *)iov,
-						       hdr->iovec_count,
+			hdr->iovec_count = iov_shorten(iov, hdr->iovec_count,
 						       hdr->dxfer_len);
 			iov_data_len = hdr->dxfer_len;
 		}
diff --git a/fs/bio.c b/fs/bio.c
index 70e5153..9d13f21 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -28,7 +28,6 @@
 #include <linux/blktrace_api.h>
 #include <linux/pfn.h>
 #include <trace/block.h>
-#include <scsi/sg.h>		/* for struct sg_iovec */
 
 DEFINE_TRACE(block_split);
 
@@ -656,17 +655,17 @@ int bio_add_page(struct bio *bio, struct page *page, unsigned int len,
 
 struct bio_map_data {
 	struct bio_vec *iovecs;
-	struct sg_iovec *sgvecs;
+	struct iovec *sgvecs;
 	int nr_sgvecs;
 	int is_our_pages;
 };
 
 static void bio_set_map_data(struct bio_map_data *bmd, struct bio *bio,
-			     struct sg_iovec *iov, int iov_count,
+			     struct iovec *iov, int iov_count,
 			     int is_our_pages)
 {
 	memcpy(bmd->iovecs, bio->bi_io_vec, sizeof(struct bio_vec) * bio->bi_vcnt);
-	memcpy(bmd->sgvecs, iov, sizeof(struct sg_iovec) * iov_count);
+	memcpy(bmd->sgvecs, iov, sizeof(struct iovec) * iov_count);
 	bmd->nr_sgvecs = iov_count;
 	bmd->is_our_pages = is_our_pages;
 	bio->bi_private = bmd;
@@ -693,7 +692,7 @@ static struct bio_map_data *bio_alloc_map_data(int nr_segs, int iov_count,
 		return NULL;
 	}
 
-	bmd->sgvecs = kmalloc(sizeof(struct sg_iovec) * iov_count, gfp_mask);
+	bmd->sgvecs = kmalloc(sizeof(struct iovec) * iov_count, gfp_mask);
 	if (bmd->sgvecs)
 		return bmd;
 
@@ -703,7 +702,7 @@ static struct bio_map_data *bio_alloc_map_data(int nr_segs, int iov_count,
 }
 
 static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs,
-			  struct sg_iovec *iov, int iov_count, int uncopy,
+			  struct iovec *iov, int iov_count, int uncopy,
 			  int do_free_page)
 {
 	int ret = 0, i;
@@ -789,7 +788,7 @@ int bio_uncopy_user(struct bio *bio)
  */
 struct bio *bio_copy_user_iov(struct request_queue *q,
 			      struct rq_map_data *map_data,
-			      struct sg_iovec *iov, int iov_count, int rw,
+			      struct iovec *iov, int iov_count, int rw,
 			      gfp_t gfp_mask)
 {
 	struct bio_map_data *bmd;
@@ -909,7 +908,7 @@ struct bio *bio_copy_user(struct request_queue *q, struct rq_map_data *map_data,
 			  unsigned long uaddr, unsigned int len, int rw,
 			  gfp_t gfp_mask)
 {
-	struct sg_iovec iov;
+	struct iovec iov;
 
 	iov.iov_base = (void __user *)uaddr;
 	iov.iov_len = len;
@@ -919,7 +918,7 @@ struct bio *bio_copy_user(struct request_queue *q, struct rq_map_data *map_data,
 
 static struct bio *__bio_map_user_iov(struct request_queue *q,
 				      struct block_device *bdev,
-				      struct sg_iovec *iov, int iov_count,
+				      struct iovec *iov, int iov_count,
 				      int rw, gfp_t gfp_mask)
 {
 	int i, j;
@@ -1044,7 +1043,7 @@ struct bio *bio_map_user(struct request_queue *q, struct block_device *bdev,
 			 unsigned long uaddr, unsigned int len, int rw,
 			 gfp_t gfp_mask)
 {
-	struct sg_iovec iov;
+	struct iovec iov;
 
 	iov.iov_base = (void __user *)uaddr;
 	iov.iov_len = len;
@@ -1053,7 +1052,7 @@ struct bio *bio_map_user(struct request_queue *q, struct block_device *bdev,
 }
 
 /**
- *	bio_map_user_iov - map user sg_iovec table into bio
+ *	bio_map_user_iov - map user iovec table into bio
  *	@q: the struct request_queue for the bio
  *	@bdev: destination block device
  *	@iov:	the iovec.
@@ -1065,7 +1064,7 @@ struct bio *bio_map_user(struct request_queue *q, struct block_device *bdev,
  *	device. Returns an error pointer in case of error.
  */
 struct bio *bio_map_user_iov(struct request_queue *q, struct block_device *bdev,
-			     struct sg_iovec *iov, int iov_count, int rw,
+			     struct iovec *iov, int iov_count, int rw,
 			     gfp_t gfp_mask)
 {
 	struct bio *bio;
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 45f56d2..8215ded 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -23,6 +23,7 @@
 #include <linux/highmem.h>
 #include <linux/mempool.h>
 #include <linux/ioprio.h>
+#include <linux/uio.h>
 
 #ifdef CONFIG_BLOCK
 
@@ -356,7 +357,6 @@ struct bio_pair {
 };
 
 struct request_queue;
-struct sg_iovec;
 struct rq_map_data;
 
 struct bio_pair *bio_split(struct bio *bi, int first_sectors);
@@ -390,7 +390,7 @@ struct bio *bio_map_user(struct request_queue *q, struct block_device *bdev,
 			 unsigned long uaddr, unsigned int len, int rw,
 			 gfp_t gfp_mask);
 struct bio *bio_map_user_iov(struct request_queue *q, struct block_device *bdev,
-			     struct sg_iovec *iov, int iov_count, int rw,
+			     struct iovec *iov, int iov_count, int rw,
 			     gfp_t gfp_mask);
 void bio_unmap_user(struct bio *bio);
 struct bio *bio_copy_user(struct request_queue *q, struct rq_map_data *map_data,
@@ -398,7 +398,7 @@ struct bio *bio_copy_user(struct request_queue *q, struct rq_map_data *map_data,
 			  gfp_t gfp_mask);
 struct bio *bio_copy_user_iov(struct request_queue *q,
 			      struct rq_map_data *map_data,
-			      struct sg_iovec *iov, int iov_count, int rw,
+			      struct iovec *iov, int iov_count, int rw,
 			      gfp_t gfp_mask);
 int bio_uncopy_user(struct bio *bio);
 struct bio *bio_map_kern(struct request_queue *q, void *data, unsigned int len,
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 465d6ba..d7bb20c 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -19,6 +19,7 @@
 #include <linux/gfp.h>
 #include <linux/bsg.h>
 #include <linux/smp.h>
+#include <linux/uio.h>
 
 #include <asm/scatterlist.h>
 
@@ -29,7 +30,6 @@ struct elevator_queue;
 struct request_pm_state;
 struct blk_trace;
 struct request;
-struct sg_io_hdr;
 
 #define BLKDEV_MIN_RQ	4
 #define BLKDEV_MAX_RQ	128	/* Default maximum */
@@ -781,9 +781,9 @@ extern int blk_rq_map_user(struct request_queue *, struct request *,
 			   gfp_t);
 extern int blk_rq_unmap_user(struct bio *);
 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
-extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
-			       struct rq_map_data *, struct sg_iovec *, int,
-			       unsigned int, gfp_t);
+extern int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
+			       struct rq_map_data *map_data, struct iovec *iov,
+			       int iov_count, unsigned int len, gfp_t gfp_mask);
 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
 			  struct request *, int);
 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
-- 
1.6.0.2