From patchwork Tue Mar 15 16:28:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Trond Myklebust X-Patchwork-Id: 12781640 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 E17ECC433EF for ; Tue, 15 Mar 2022 16:34:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350098AbiCOQfr (ORCPT ); Tue, 15 Mar 2022 12:35:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350096AbiCOQfq (ORCPT ); Tue, 15 Mar 2022 12:35:46 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 478CB57152 for ; Tue, 15 Mar 2022 09:34:34 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id F1D6EB817C9 for ; Tue, 15 Mar 2022 16:34:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 41BEFC340E8 for ; Tue, 15 Mar 2022 16:34:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1647362071; bh=rcI4//gyqZpaPNsAijYqAv9OYh2/LcrZiCHX90zE9EE=; h=From:To:Subject:Date:From; b=Dg3hJyymoegauB/98KMGwWW4m045Ti/JwpXhYaOTFp4MW3VRxcZxqj4XSPzsJfk9o yEFAGuJlxjNQ3utGIREBCAdq9zxs+zdUpqVuhlzkjnOtr6X65hi1P681rEew4Uibml Bw72BzndQI9JVlwEEPCp9uPT/OdValQTJsWLoJz+Ljnlo7VkMcWZTzKQliYtTaRWF9 FT15YUQnhrM9S3ZcF+wzKSqQ8YeveF01uZ64sET9Xsx+Ln07HLg5m0pDTiE94DCQfK BfLmtjWpudvN3CVPGA5D1pJwCQw4fTLN6OvnTHpyxk84tn9rdLa3reimq3jlG+JJ6s NLSzJ3d9IfWFg== From: trondmy@kernel.org To: linux-nfs@vger.kernel.org Subject: [PATCH 1/3] SUNRPC: Fix socket waits for write buffer space Date: Tue, 15 Mar 2022 12:28:03 -0400 Message-Id: <20220315162805.570850-1-trondmy@kernel.org> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org From: Trond Myklebust The socket layer requires that we use the socket lock to protect changes to the sock->sk_write_pending field and others. Reported-by: Chuck Lever Signed-off-by: Trond Myklebust --- net/sunrpc/xprtsock.c | 54 +++++++++++++++++++++++++++++++------------ 1 file changed, 39 insertions(+), 15 deletions(-) diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 7e39f87cde2d..786df8c0cda3 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -763,12 +763,12 @@ xs_stream_start_connect(struct sock_xprt *transport) /** * xs_nospace - handle transmit was incomplete * @req: pointer to RPC request + * @transport: pointer to struct sock_xprt * */ -static int xs_nospace(struct rpc_rqst *req) +static int xs_nospace(struct rpc_rqst *req, struct sock_xprt *transport) { - struct rpc_xprt *xprt = req->rq_xprt; - struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt); + struct rpc_xprt *xprt = &transport->xprt; struct sock *sk = transport->inet; int ret = -EAGAIN; @@ -779,25 +779,49 @@ static int xs_nospace(struct rpc_rqst *req) /* Don't race with disconnect */ if (xprt_connected(xprt)) { + struct socket_wq *wq; + + rcu_read_lock(); + wq = rcu_dereference(sk->sk_wq); + set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags); + rcu_read_unlock(); + /* wait for more buffer space */ + set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); sk->sk_write_pending++; xprt_wait_for_buffer_space(xprt); } else ret = -ENOTCONN; spin_unlock(&xprt->transport_lock); + return ret; +} - /* Race breaker in case memory is freed before above code is called */ - if (ret == -EAGAIN) { - struct socket_wq *wq; +static int xs_sock_nospace(struct rpc_rqst *req) +{ + struct sock_xprt *transport = + container_of(req->rq_xprt, struct sock_xprt, xprt); + struct sock *sk = transport->inet; + int ret = -EAGAIN; - rcu_read_lock(); - wq = rcu_dereference(sk->sk_wq); - set_bit(SOCKWQ_ASYNC_NOSPACE, &wq->flags); - rcu_read_unlock(); + lock_sock(sk); + if (!sock_writeable(sk)) + ret = xs_nospace(req, transport); + release_sock(sk); + return ret; +} - sk->sk_write_space(sk); - } +static int xs_stream_nospace(struct rpc_rqst *req) +{ + struct sock_xprt *transport = + container_of(req->rq_xprt, struct sock_xprt, xprt); + struct sock *sk = transport->inet; + int ret = -EAGAIN; + + lock_sock(sk); + if (!sk_stream_memory_free(sk)) + ret = xs_nospace(req, transport); + release_sock(sk); return ret; } @@ -887,7 +911,7 @@ static int xs_local_send_request(struct rpc_rqst *req) case -ENOBUFS: break; case -EAGAIN: - status = xs_nospace(req); + status = xs_stream_nospace(req); break; default: dprintk("RPC: sendmsg returned unrecognized error %d\n", @@ -963,7 +987,7 @@ static int xs_udp_send_request(struct rpc_rqst *req) /* Should we call xs_close() here? */ break; case -EAGAIN: - status = xs_nospace(req); + status = xs_sock_nospace(req); break; case -ENETUNREACH: case -ENOBUFS: @@ -1083,7 +1107,7 @@ static int xs_tcp_send_request(struct rpc_rqst *req) /* Should we call xs_close() here? */ break; case -EAGAIN: - status = xs_nospace(req); + status = xs_stream_nospace(req); break; case -ECONNRESET: case -ECONNREFUSED: