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-rw-r--r--drivers/scsi/sg.c4
-rw-r--r--fs/bio.c22
-rw-r--r--include/linux/blkdev.h1
3 files changed, 17 insertions, 10 deletions
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 4d6f2fe..9230402 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -1656,6 +1656,10 @@ static int sg_start_req(Sg_request *srp, unsigned char *cmd)
md->nr_entries = req_schp->k_use_sg;
md->offset = 0;
md->null_mapped = hp->dxferp ? 0 : 1;
+ if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
+ md->from_user = 1;
+ else
+ md->from_user = 0;
}
if (iov_count) {
diff --git a/fs/bio.c b/fs/bio.c
index 1486b19..7673800 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -705,14 +705,13 @@ 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,
- int do_free_page)
+ struct sg_iovec *iov, int iov_count,
+ int to_user, int from_user, int do_free_page)
{
int ret = 0, i;
struct bio_vec *bvec;
int iov_idx = 0;
unsigned int iov_off = 0;
- int read = bio_data_dir(bio) == READ;
__bio_for_each_segment(bvec, bio, i, 0) {
char *bv_addr = page_address(bvec->bv_page);
@@ -727,13 +726,14 @@ static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs,
iov_addr = iov[iov_idx].iov_base + iov_off;
if (!ret) {
- if (!read && !uncopy)
- ret = copy_from_user(bv_addr, iov_addr,
- bytes);
- if (read && uncopy)
+ if (to_user)
ret = copy_to_user(iov_addr, bv_addr,
bytes);
+ if (from_user)
+ ret = copy_from_user(bv_addr, iov_addr,
+ bytes);
+
if (ret)
ret = -EFAULT;
}
@@ -770,7 +770,8 @@ int bio_uncopy_user(struct bio *bio)
if (!bio_flagged(bio, BIO_NULL_MAPPED))
ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs,
- bmd->nr_sgvecs, 1, bmd->is_our_pages);
+ bmd->nr_sgvecs, bio_data_dir(bio) == READ,
+ 0, bmd->is_our_pages);
bio_free_map_data(bmd);
bio_put(bio);
return ret;
@@ -875,8 +876,9 @@ struct bio *bio_copy_user_iov(struct request_queue *q,
/*
* success
*/
- 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 ((!write_to_vm && (!map_data || !map_data->null_mapped)) ||
+ (map_data && map_data->from_user)) {
+ ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0, 1, 0);
if (ret)
goto cleanup;
}
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index bb3d399..0146e0f 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -723,6 +723,7 @@ struct rq_map_data {
int nr_entries;
unsigned long offset;
int null_mapped;
+ int from_user;
};
struct req_iterator {
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