From patchwork Mon May 22 12:11:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13250298 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 05606C7EE2A for ; Mon, 22 May 2023 12:11:55 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 93869900008; Mon, 22 May 2023 08:11:54 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 89A18900002; Mon, 22 May 2023 08:11:54 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7152E900008; Mon, 22 May 2023 08:11:54 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 5C27E900002 for ; Mon, 22 May 2023 08:11:54 -0400 (EDT) Received: from smtpin12.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 383A3C022C for ; Mon, 22 May 2023 12:11:54 +0000 (UTC) X-FDA: 80817777348.12.6C15BB7 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf06.hostedemail.com (Postfix) with ESMTP id 61FE9180002 for ; Mon, 22 May 2023 12:11:52 +0000 (UTC) Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=BdfMOBfH; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf06.hostedemail.com: domain of dhowells@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=dhowells@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1684757512; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=79TjdqGEZWzMR9284kh0SsbKnhgq/mMmLDGgzzPhuR4=; b=SAr93o/PyWa37GoupUnfPhz9zut+DYBSCsvNopomluv3rgihrqY5mQIOdM3wUlCgt4sN/C MQPZD6S+1k9iytHGchJqd77Urfcs2ag5/F/C/E1s0G3+uLhC2AUx/hyk0K6ax8FbwOIBYl mvM8Gu8ppQYoeUm7oaENoK1MIpZxHq4= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=BdfMOBfH; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf06.hostedemail.com: domain of dhowells@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=dhowells@redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1684757512; a=rsa-sha256; cv=none; b=ke9EOezildbRwGm1IgiGY9ovJXDDPAVsTEgjRhqs3UJzqGD9/N0wXKIuM0jx8wgzVdAnBC JKhnJDLkw5RaomVFHwkyFpa8HHQY+s0H7HLPugIftr1a20sWRuUBqFh6q3CdHbw6ygDhI1 ZOusoEfCEPRq/zQNVe0fChp3X6ypl/g= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684757511; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=79TjdqGEZWzMR9284kh0SsbKnhgq/mMmLDGgzzPhuR4=; b=BdfMOBfH12UbPi9wnkVGopOGB+VUo2KZ4BBQ+kcPZc6pWRFvU2aGAMnP5sV20wNirSqowE F8o2oZmF7hlEn+u24/jPhqPu1PYhDiYW90JJyPMae+ofjQVTS4RjN6XjyNNpa272YwCaG5 j4Dv5GnLhk6EJ2uIkVtDlLlV53ZSf4Y= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-13-s8VTVl0_ND6DLvjr5Pd7CA-1; Mon, 22 May 2023 08:11:48 -0400 X-MC-Unique: s8VTVl0_ND6DLvjr5Pd7CA-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 87AEA3800E87; Mon, 22 May 2023 12:11:46 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.39.192.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id 14AA7492B0A; Mon, 22 May 2023 12:11:43 +0000 (UTC) From: David Howells To: netdev@vger.kernel.org Cc: David Howells , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Willem de Bruijn , David Ahern , Matthew Wilcox , Al Viro , Christoph Hellwig , Jens Axboe , Jeff Layton , Christian Brauner , Chuck Lever III , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH net-next v10 05/16] tcp: Convert do_tcp_sendpages() to use MSG_SPLICE_PAGES Date: Mon, 22 May 2023 13:11:14 +0100 Message-Id: <20230522121125.2595254-6-dhowells@redhat.com> In-Reply-To: <20230522121125.2595254-1-dhowells@redhat.com> References: <20230522121125.2595254-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 X-Rspamd-Queue-Id: 61FE9180002 X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: bgqpq1o1btcx7jmda4szy3a93czdh3bt X-HE-Tag: 1684757512-712837 X-HE-Meta: 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 J076IHZa 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Convert do_tcp_sendpages() to use sendmsg() with MSG_SPLICE_PAGES rather than directly splicing in the pages itself. do_tcp_sendpages() can then be inlined in subsequent patches into its callers. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. Signed-off-by: David Howells cc: Eric Dumazet cc: "David S. Miller" cc: David Ahern cc: Jakub Kicinski cc: Paolo Abeni cc: Jens Axboe cc: Matthew Wilcox cc: netdev@vger.kernel.org --- net/ipv4/tcp.c | 158 +++---------------------------------------------- 1 file changed, 7 insertions(+), 151 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 2d61150d01f1..f3a0c02678e0 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -974,163 +974,19 @@ static int tcp_wmem_schedule(struct sock *sk, int copy) return min(copy, sk->sk_forward_alloc); } -static struct sk_buff *tcp_build_frag(struct sock *sk, int size_goal, int flags, - struct page *page, int offset, size_t *size) -{ - struct sk_buff *skb = tcp_write_queue_tail(sk); - struct tcp_sock *tp = tcp_sk(sk); - bool can_coalesce; - int copy, i; - - if (!skb || (copy = size_goal - skb->len) <= 0 || - !tcp_skb_can_collapse_to(skb)) { -new_segment: - if (!sk_stream_memory_free(sk)) - return NULL; - - skb = tcp_stream_alloc_skb(sk, 0, sk->sk_allocation, - tcp_rtx_and_write_queues_empty(sk)); - if (!skb) - return NULL; - -#ifdef CONFIG_TLS_DEVICE - skb->decrypted = !!(flags & MSG_SENDPAGE_DECRYPTED); -#endif - tcp_skb_entail(sk, skb); - copy = size_goal; - } - - if (copy > *size) - copy = *size; - - i = skb_shinfo(skb)->nr_frags; - can_coalesce = skb_can_coalesce(skb, i, page, offset); - if (!can_coalesce && i >= READ_ONCE(sysctl_max_skb_frags)) { - tcp_mark_push(tp, skb); - goto new_segment; - } - if (tcp_downgrade_zcopy_pure(sk, skb)) - return NULL; - - copy = tcp_wmem_schedule(sk, copy); - if (!copy) - return NULL; - - if (can_coalesce) { - skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy); - } else { - get_page(page); - skb_fill_page_desc_noacc(skb, i, page, offset, copy); - } - - if (!(flags & MSG_NO_SHARED_FRAGS)) - skb_shinfo(skb)->flags |= SKBFL_SHARED_FRAG; - - skb->len += copy; - skb->data_len += copy; - skb->truesize += copy; - sk_wmem_queued_add(sk, copy); - sk_mem_charge(sk, copy); - WRITE_ONCE(tp->write_seq, tp->write_seq + copy); - TCP_SKB_CB(skb)->end_seq += copy; - tcp_skb_pcount_set(skb, 0); - - *size = copy; - return skb; -} - ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset, size_t size, int flags) { - struct tcp_sock *tp = tcp_sk(sk); - int mss_now, size_goal; - int err; - ssize_t copied; - long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); - - if (IS_ENABLED(CONFIG_DEBUG_VM) && - WARN_ONCE(!sendpage_ok(page), - "page must not be a Slab one and have page_count > 0")) - return -EINVAL; - - /* Wait for a connection to finish. One exception is TCP Fast Open - * (passive side) where data is allowed to be sent before a connection - * is fully established. - */ - if (((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) && - !tcp_passive_fastopen(sk)) { - err = sk_stream_wait_connect(sk, &timeo); - if (err != 0) - goto out_err; - } + struct bio_vec bvec; + struct msghdr msg = { .msg_flags = flags | MSG_SPLICE_PAGES, }; - sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); + bvec_set_page(&bvec, page, size, offset); + iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, size); - mss_now = tcp_send_mss(sk, &size_goal, flags); - copied = 0; + if (flags & MSG_SENDPAGE_NOTLAST) + msg.msg_flags |= MSG_MORE; - err = -EPIPE; - if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) - goto out_err; - - while (size > 0) { - struct sk_buff *skb; - size_t copy = size; - - skb = tcp_build_frag(sk, size_goal, flags, page, offset, ©); - if (!skb) - goto wait_for_space; - - if (!copied) - TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_PSH; - - copied += copy; - offset += copy; - size -= copy; - if (!size) - goto out; - - if (skb->len < size_goal || (flags & MSG_OOB)) - continue; - - if (forced_push(tp)) { - tcp_mark_push(tp, skb); - __tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_PUSH); - } else if (skb == tcp_send_head(sk)) - tcp_push_one(sk, mss_now); - continue; - -wait_for_space: - set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); - tcp_push(sk, flags & ~MSG_MORE, mss_now, - TCP_NAGLE_PUSH, size_goal); - - err = sk_stream_wait_memory(sk, &timeo); - if (err != 0) - goto do_error; - - mss_now = tcp_send_mss(sk, &size_goal, flags); - } - -out: - if (copied) { - tcp_tx_timestamp(sk, sk->sk_tsflags); - if (!(flags & MSG_SENDPAGE_NOTLAST)) - tcp_push(sk, flags, mss_now, tp->nonagle, size_goal); - } - return copied; - -do_error: - tcp_remove_empty_skb(sk); - if (copied) - goto out; -out_err: - /* make sure we wake any epoll edge trigger waiter */ - if (unlikely(tcp_rtx_and_write_queues_empty(sk) && err == -EAGAIN)) { - sk->sk_write_space(sk); - tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED); - } - return sk_stream_error(sk, flags, err); + return tcp_sendmsg_locked(sk, &msg, size); } EXPORT_SYMBOL_GPL(do_tcp_sendpages);