From patchwork Tue Apr 11 16:09:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Howells X-Patchwork-Id: 13207845 X-Patchwork-Delegate: kuba@kernel.org 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4F1F4C76196 for ; Tue, 11 Apr 2023 16:13:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230505AbjDKQNF (ORCPT ); Tue, 11 Apr 2023 12:13:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39722 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230087AbjDKQMB (ORCPT ); Tue, 11 Apr 2023 12:12:01 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C4B8A5FD5 for ; Tue, 11 Apr 2023 09:10:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1681229411; 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=NUYtJHWQHrlxATmFk6Zj0PzfCOzptdZvrIQb9VoBGYI=; b=HnT+DotneCt7DR7al3+YPTg0/+0XYiczODYFIzdw7vSZ9OGn0dR6Z4gZX/Z+0ik17mevvk 6o1sbsBHMTA4tcFw1NzMl1b00OBWsCE1VM11HePvDkbA8sgi3XAKXd2vVR8HpHwp4IYQpM 0QV0007t7UuJ7n5/TL+vtDFNgLynf2k= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-344-v6vTLpRuNC-A8BVR-fqWyA-1; Tue, 11 Apr 2023 12:10:05 -0400 X-MC-Unique: v6vTLpRuNC-A8BVR-fqWyA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 3EF7F101A551; Tue, 11 Apr 2023 16:10:04 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.33.36.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0B5F52166B31; Tue, 11 Apr 2023 16:10:01 +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, Kuniyuki Iwashima Subject: [PATCH net-next v6 18/18] af_unix: Support MSG_SPLICE_PAGES Date: Tue, 11 Apr 2023 17:09:02 +0100 Message-Id: <20230411160902.4134381-19-dhowells@redhat.com> In-Reply-To: <20230411160902.4134381-1-dhowells@redhat.com> References: <20230411160902.4134381-1-dhowells@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Make AF_UNIX sendmsg() support MSG_SPLICE_PAGES, splicing in pages from the source iterator if possible and copying the data in otherwise. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. Signed-off-by: David Howells cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: Kuniyuki Iwashima cc: Jens Axboe cc: Matthew Wilcox cc: netdev@vger.kernel.org --- Notes: ver #6) - Use common helper. net/unix/af_unix.c | 49 +++++++++++++++++++++++++++++++--------------- 1 file changed, 33 insertions(+), 16 deletions(-) diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index ea45dcc80232..e1f962180e55 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -2200,19 +2200,25 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg, while (sent < len) { size = len - sent; - /* Keep two messages in the pipe so it schedules better */ - size = min_t(int, size, (sk->sk_sndbuf >> 1) - 64); + if (unlikely(msg->msg_flags & MSG_SPLICE_PAGES)) { + skb = sock_alloc_send_pskb(sk, 0, 0, + msg->msg_flags & MSG_DONTWAIT, + &err, 0); + } else { + /* Keep two messages in the pipe so it schedules better */ + size = min_t(int, size, (sk->sk_sndbuf >> 1) - 64); - /* allow fallback to order-0 allocations */ - size = min_t(int, size, SKB_MAX_HEAD(0) + UNIX_SKB_FRAGS_SZ); + /* allow fallback to order-0 allocations */ + size = min_t(int, size, SKB_MAX_HEAD(0) + UNIX_SKB_FRAGS_SZ); - data_len = max_t(int, 0, size - SKB_MAX_HEAD(0)); + data_len = max_t(int, 0, size - SKB_MAX_HEAD(0)); - data_len = min_t(size_t, size, PAGE_ALIGN(data_len)); + data_len = min_t(size_t, size, PAGE_ALIGN(data_len)); - skb = sock_alloc_send_pskb(sk, size - data_len, data_len, - msg->msg_flags & MSG_DONTWAIT, &err, - get_order(UNIX_SKB_FRAGS_SZ)); + skb = sock_alloc_send_pskb(sk, size - data_len, data_len, + msg->msg_flags & MSG_DONTWAIT, &err, + get_order(UNIX_SKB_FRAGS_SZ)); + } if (!skb) goto out_err; @@ -2224,13 +2230,24 @@ static int unix_stream_sendmsg(struct socket *sock, struct msghdr *msg, } fds_sent = true; - skb_put(skb, size - data_len); - skb->data_len = data_len; - skb->len = size; - err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, size); - if (err) { - kfree_skb(skb); - goto out_err; + if (unlikely(msg->msg_flags & MSG_SPLICE_PAGES)) { + err = skb_splice_from_iter(skb, &msg->msg_iter, size, + sk->sk_allocation); + if (err < 0) { + kfree_skb(skb); + goto out_err; + } + size = err; + refcount_add(size, &sk->sk_wmem_alloc); + } else { + skb_put(skb, size - data_len); + skb->data_len = data_len; + skb->len = size; + err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, size); + if (err) { + kfree_skb(skb); + goto out_err; + } } unix_state_lock(other);