@@ -870,17 +870,22 @@ static void pipe_advance(struct iov_iter *i, size_t size)
static void iov_iter_bvec_advance(struct iov_iter *i, size_t size)
{
- struct bvec_iter bi;
+ const struct bio_vec *bvec, *end;
- bi.bi_size = i->count;
- bi.bi_bvec_done = i->iov_offset;
- bi.bi_idx = 0;
- bvec_iter_advance(i->bvec, &bi, size);
+ if (!i->count)
+ return;
+ i->count -= size;
+
+ size += i->iov_offset;
- i->bvec += bi.bi_idx;
- i->nr_segs -= bi.bi_idx;
- i->count = bi.bi_size;
- i->iov_offset = bi.bi_bvec_done;
+ for (bvec = i->bvec, end = bvec + i->nr_segs; bvec < end; bvec++) {
+ if (likely(size < bvec->bv_len))
+ break;
+ size -= bvec->bv_len;
+ }
+ i->iov_offset = size;
+ i->nr_segs -= bvec - i->bvec;
+ i->bvec = bvec;
}
static void iov_iter_iovec_advance(struct iov_iter *i, size_t size)
do what we do for iovec/kvec; that ends up generating better code, AFAICS. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> --- lib/iov_iter.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-)