The commit 818827669d85b84241696ffef2de485db46b0b5e (block: make
blk_rq_map_user take a NULL user-space buffer) extended
blk_rq_map_user to accept a NULL user-space buffer with a READ
command. It was necessary to convert sg to use the block layer mapping
API.
This patch extends blk_rq_map_user again for a WRITE command. It is
necessary to convert st and osst drivers to use the block layer
apping API.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx>
Cc: Jens Axboe <jens.axboe@xxxxxxxxxx>
---
block/blk-map.c | 16 +++++++---------
drivers/scsi/sg.c | 1 +
fs/bio.c | 2 +-
include/linux/blkdev.h | 1 +
4 files changed, 10 insertions(+), 10 deletions(-)
diff --git a/block/blk-map.c b/block/blk-map.c
index 0f4b4b8..e1bb727 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -42,7 +42,7 @@ static int __blk_rq_unmap_user(struct bio *bio)
static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
struct rq_map_data *map_data, void __user *ubuf,
- unsigned int len, int null_mapped, gfp_t gfp_mask)
+ unsigned int len, gfp_t gfp_mask)
{
unsigned long uaddr;
struct bio *bio, *orig_bio;
@@ -63,7 +63,7 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
if (IS_ERR(bio))
return PTR_ERR(bio);
- if (null_mapped)
+ if (map_data && map_data->null_mapped)
bio->bi_flags |= (1 << BIO_NULL_MAPPED);
orig_bio = bio;
@@ -114,17 +114,15 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
{
unsigned long bytes_read = 0;
struct bio *bio = NULL;
- int ret, null_mapped = 0;
+ int ret;
if (len > (q->max_hw_sectors << 9))
return -EINVAL;
if (!len)
return -EINVAL;
- if (!ubuf) {
- if (!map_data || rq_data_dir(rq) != READ)
- return -EINVAL;
- null_mapped = 1;
- }
+
+ if (!ubuf && (!map_data || !map_data->null_mapped))
+ return -EINVAL;
while (bytes_read != len) {
unsigned long map_len, end, start;
@@ -143,7 +141,7 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
map_len -= PAGE_SIZE;
ret = __blk_rq_map_user(q, rq, map_data, ubuf, map_len,
- null_mapped, gfp_mask);
+ gfp_mask);
if (ret < 0)
goto unmap_rq;
if (!bio)
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 5103855..820a228 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -1669,6 +1669,7 @@ static int sg_start_req(Sg_request *srp, unsigned char *cmd)
md->pages = req_schp->pages;
md->page_order = req_schp->page_order;
md->nr_entries = req_schp->k_use_sg;
+ md->null_mapped = hp->dxferp ? 0 : 1;
}
if (iov_count)
diff --git a/fs/bio.c b/fs/bio.c
index 77a55bc..25f456b 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -698,7 +698,7 @@ struct bio *bio_copy_user_iov(struct request_queue *q,
/*
* success
*/
- if (!write_to_vm) {
+ if (!write_to_vm && (!map_data || !map_data->null_mapped)) {
ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0, 0);
if (ret)
goto cleanup;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index a135256..39807a9 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -680,6 +680,7 @@ struct rq_map_data {
struct page **pages;
int page_order;
int nr_entries;
+ int null_mapped;
};
struct req_iterator {
--
1.5.6.5
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
