Commit 7491a2bf authored by Al Viro's avatar Al Viro
Browse files

iterate_bvec(): expand bvec.h macro forest, massage a bit 



... incidentally, using pointer instead of index in an array
(the only change here) trims half-kilobyte of .text...

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 5c67aa90

lib/iov_iter.c

+20 −13
Original line number Diff line number Diff line
@@ -37,14 +37,23 @@ 
	n = wanted - n;						\

}



#define iterate_bvec(i, n, __v, __bi, skip, STEP) {	\

	struct bvec_iter __start;			\

	__start.bi_size = n;				\

	__start.bi_bvec_done = skip;			\

	__start.bi_idx = 0;				\

	for_each_bvec(__v, i->bvec, __bi, __start) {	\

#define iterate_bvec(i, n, __v, p, skip, STEP) {		\

	size_t wanted = n;					\

	while (n) {						\

		unsigned offset = p->bv_offset + skip;		\

		__v.bv_offset = offset % PAGE_SIZE;		\

		__v.bv_page = p->bv_page + offset / PAGE_SIZE;	\

		__v.bv_len = min(min(n, p->bv_len - skip),	\

		     (size_t)(PAGE_SIZE - offset % PAGE_SIZE));	\

		(void)(STEP);					\

		skip += __v.bv_len;				\

		if (skip == p->bv_len) {			\

			skip = 0;				\

			p++;					\

		}						\

		n -= __v.bv_len;				\

	}							\

	n = wanted - n;						\

}



#define iterate_xarray(i, n, __v, skip, STEP) {		\
@@ -98,11 +107,9 @@ 
		} else if (iov_iter_is_bvec(i)) {		\

			const struct bio_vec *bvec = i->bvec;	\

			struct bio_vec v;			\

			struct bvec_iter __bi;			\

			iterate_bvec(i, n, v, __bi, skip, (B))	\

			i->bvec = __bvec_iter_bvec(i->bvec, __bi);	\

			i->nr_segs -= i->bvec - bvec;		\

			skip = __bi.bi_bvec_done;		\

			iterate_bvec(i, n, v, bvec, skip, (B))	\

			i->nr_segs -= bvec - i->bvec;		\

			i->bvec = bvec;				\

		} else if (iov_iter_is_kvec(i)) {		\

			const struct kvec *kvec = i->kvec;	\

			struct kvec v;				\