new helper: iov_iter_kvec()

initialization of kvec-backed iov_iter

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2014-11-24 14:46:11 -05:00
parent a604ec7e9f
commit abb78f875f
2 changed files with 15 additions and 0 deletions

View File

@ -87,6 +87,8 @@ size_t iov_iter_zero(size_t bytes, struct iov_iter *);
unsigned long iov_iter_alignment(const struct iov_iter *i);
void iov_iter_init(struct iov_iter *i, int direction, const struct iovec *iov,
unsigned long nr_segs, size_t count);
void iov_iter_kvec(struct iov_iter *i, int direction, const struct kvec *iov,
unsigned long nr_segs, size_t count);
ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages,
size_t maxsize, unsigned maxpages, size_t *start);
ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, struct page ***pages,

View File

@ -479,6 +479,19 @@ size_t iov_iter_single_seg_count(const struct iov_iter *i)
}
EXPORT_SYMBOL(iov_iter_single_seg_count);
void iov_iter_kvec(struct iov_iter *i, int direction,
const struct kvec *iov, unsigned long nr_segs,
size_t count)
{
BUG_ON(!(direction & ITER_KVEC));
i->type = direction;
i->kvec = (struct kvec *)iov;
i->nr_segs = nr_segs;
i->iov_offset = 0;
i->count = count;
}
EXPORT_SYMBOL(iov_iter_kvec);
unsigned long iov_iter_alignment(const struct iov_iter *i)
{
unsigned long res = 0;