diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2022-07-12 21:52:50 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-07-24 18:41:07 -0600 |
| commit | 3ff1a0d395c00e42ee15f561431e0c04097595b9 (patch) | |
| tree | c23b6653e92d419544aaa9f647b6a8b4f4dcc1e9 /io_uring/net.c | |
| parent | 492dddb4f6e3a5839c27d41ff1fecdbe6c3ab851 (diff) | |
| download | lwn-3ff1a0d395c00e42ee15f561431e0c04097595b9.tar.gz lwn-3ff1a0d395c00e42ee15f561431e0c04097595b9.zip | |
io_uring: enable managed frags with register buffers
io_uring's registered buffers infra has a good performant way of pinning
pages, so let's use SKBFL_MANAGED_FRAG_REFS when our requests are purely
register buffer backed.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/278731d3f20caf346cfc025fbee0b4c9ee4ed751.1657643355.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring/net.c')
| -rw-r--r-- | io_uring/net.c | 56 |
1 files changed, 55 insertions, 1 deletions
diff --git a/io_uring/net.c b/io_uring/net.c index 9ac2ce37c522..62be89837d82 100644 --- a/io_uring/net.c +++ b/io_uring/net.c @@ -886,6 +886,60 @@ int io_sendzc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return 0; } +static int io_sg_from_iter(struct sock *sk, struct sk_buff *skb, + struct iov_iter *from, size_t length) +{ + struct skb_shared_info *shinfo = skb_shinfo(skb); + int frag = shinfo->nr_frags; + int ret = 0; + struct bvec_iter bi; + ssize_t copied = 0; + unsigned long truesize = 0; + + if (!shinfo->nr_frags) + shinfo->flags |= SKBFL_MANAGED_FRAG_REFS; + + if (!skb_zcopy_managed(skb) || !iov_iter_is_bvec(from)) { + skb_zcopy_downgrade_managed(skb); + return __zerocopy_sg_from_iter(NULL, sk, skb, from, length); + } + + bi.bi_size = min(from->count, length); + bi.bi_bvec_done = from->iov_offset; + bi.bi_idx = 0; + + while (bi.bi_size && frag < MAX_SKB_FRAGS) { + struct bio_vec v = mp_bvec_iter_bvec(from->bvec, bi); + + copied += v.bv_len; + truesize += PAGE_ALIGN(v.bv_len + v.bv_offset); + __skb_fill_page_desc_noacc(shinfo, frag++, v.bv_page, + v.bv_offset, v.bv_len); + bvec_iter_advance_single(from->bvec, &bi, v.bv_len); + } + if (bi.bi_size) + ret = -EMSGSIZE; + + shinfo->nr_frags = frag; + from->bvec += bi.bi_idx; + from->nr_segs -= bi.bi_idx; + from->count = bi.bi_size; + from->iov_offset = bi.bi_bvec_done; + + skb->data_len += copied; + skb->len += copied; + skb->truesize += truesize; + + if (sk && sk->sk_type == SOCK_STREAM) { + sk_wmem_queued_add(sk, truesize); + if (!skb_zcopy_pure(skb)) + sk_mem_charge(sk, truesize); + } else { + refcount_add(truesize, &skb->sk->sk_wmem_alloc); + } + return ret; +} + int io_sendzc(struct io_kiocb *req, unsigned int issue_flags) { struct sockaddr_storage address; @@ -950,7 +1004,7 @@ int io_sendzc(struct io_kiocb *req, unsigned int issue_flags) msg.msg_flags = msg_flags; msg.msg_ubuf = ¬if->uarg; - msg.sg_from_iter = NULL; + msg.sg_from_iter = io_sg_from_iter; ret = sock_sendmsg(sock, &msg); if (unlikely(ret < min_ret)) { |