kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

bio_alloc_map_data(): do bmd->iter setup right there

Browse source 
just need to copy it iter instead of iter->nr_segs

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2017-09-24 13:14:35 -04:00
parent d16d44ebb0
commit 0e5b935d43
1 changed files with 12 additions and 8 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

20
block/bio.c
View file

@ -1070,14 +1070,21 @@ struct bio_map_data {
struct iovec iov[];
};
static struct bio_map_data *bio_alloc_map_data(unsigned int iov_count,
static struct bio_map_data *bio_alloc_map_data(struct iov_iter *data,
gfp_t gfp_mask)
{
if (iov_count > UIO_MAXIOV)
struct bio_map_data *bmd;
if (data->nr_segs > UIO_MAXIOV)
return NULL;
return kmalloc(sizeof(struct bio_map_data) +
sizeof(struct iovec) * iov_count, gfp_mask);
bmd = kmalloc(sizeof(struct bio_map_data) +
sizeof(struct iovec) * data->nr_segs, gfp_mask);
if (!bmd)
return NULL;
memcpy(bmd->iov, data->iov, sizeof(struct iovec) * data->nr_segs);
bmd->iter = *data;
bmd->iter.iov = bmd->iov;
return bmd;
}
/**
@ -1206,7 +1213,7 @@ struct bio *bio_copy_user_iov(struct request_queue *q,
unsigned int len = iter->count;
unsigned int offset = map_data ? offset_in_page(map_data->offset) : 0;
bmd = bio_alloc_map_data(iter->nr_segs, gfp_mask);
bmd = bio_alloc_map_data(iter, gfp_mask);
if (!bmd)
return ERR_PTR(-ENOMEM);
@ -1216,9 +1223,6 @@ struct bio *bio_copy_user_iov(struct request_queue *q,
* shortlived one.
*/
bmd->is_our_pages = map_data ? 0 : 1;
memcpy(bmd->iov, iter->iov, sizeof(struct iovec) * iter->nr_segs);
bmd->iter = *iter;
bmd->iter.iov = bmd->iov;
nr_pages = DIV_ROUND_UP(offset + len, PAGE_SIZE);
if (nr_pages > BIO_MAX_PAGES)