From 18fa9af7263164ec9a8d7b28a848324825f14672 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 6 Jun 2022 23:44:33 -0400 Subject: iov_iter_bvec_advance(): don't bother with bvec_iter do what we do for iovec/kvec; that ends up generating better code, AFAICS. Reviewed-by: Jeff Layton Reviewed-by: Christian Brauner (Microsoft) Signed-off-by: Al Viro --- lib/iov_iter.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) (limited to 'lib') diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 4c658a25e29c..c51314639615 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -846,17 +846,22 @@ 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) -- cgit v1.2.3-59-g8ed1b