提交 97ae77a1 编写于 作者: F FUJITA Tomonori 提交者: James Bottomley

[SCSI] block: make blk_rq_map_user take a NULL user-space buffer for WRITE

The commit 81882766 (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: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NJens Axboe <jens.axboe@oracle.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>
上级 56c451f4
......@@ -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)
......
......@@ -1670,6 +1670,7 @@ static int sg_start_req(Sg_request *srp, unsigned char *cmd)
md->page_order = req_schp->page_order;
md->nr_entries = req_schp->k_use_sg;
md->offset = 0;
md->null_mapped = hp->dxferp ? 0 : 1;
}
if (iov_count)
......
......@@ -859,7 +859,7 @@ 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;
......
......@@ -691,6 +691,7 @@ struct rq_map_data {
int page_order;
int nr_entries;
unsigned long offset;
int null_mapped;
};
struct req_iterator {
......
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