From patchwork Sun Aug 16 07:08:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Coly Li X-Patchwork-Id: 11715987 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6BFEA16B1 for ; Sun, 16 Aug 2020 07:08:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 53CD7207D3 for ; Sun, 16 Aug 2020 07:08:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730156AbgHPHIe (ORCPT ); Sun, 16 Aug 2020 03:08:34 -0400 Received: from mx2.suse.de ([195.135.220.15]:58252 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730025AbgHPHIc (ORCPT ); Sun, 16 Aug 2020 03:08:32 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 46C5AB14D; Sun, 16 Aug 2020 07:08:55 +0000 (UTC) From: Coly Li To: linux-block@vger.kernel.org, linux-nvme@lists.infradead.org Cc: netdev@vger.kernel.org, stable@vger.kernel.org, linux-kernel@vger.kernel.org, Coly Li , Chaitanya Kulkarni , Christoph Hellwig , Hannes Reinecke , Jan Kara , Jens Axboe , Mikhail Skorzhinskii , Philipp Reisner , Sagi Grimberg , Vlastimil Babka Subject: [PATCH v5 2/3] nvme-tcp: check page by sendpage_ok() before calling kernel_sendpage() Date: Sun, 16 Aug 2020 15:08:13 +0800 Message-Id: <20200816070814.6806-2-colyli@suse.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200816070814.6806-1-colyli@suse.de> References: <20200816070814.6806-1-colyli@suse.de> MIME-Version: 1.0 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Currently nvme_tcp_try_send_data() doesn't use kernel_sendpage() to send slab pages. But for pages allocated by __get_free_pages() without __GFP_COMP, which also have refcount as 0, they are still sent by kernel_sendpage() to remote end, this is problematic. The new introduced helper sendpage_ok() checks both PageSlab tag and page_count counter, and returns true if the checking page is OK to be sent by kernel_sendpage(). This patch fixes the page checking issue of nvme_tcp_try_send_data() with sendpage_ok(). If sendpage_ok() returns true, send this page by kernel_sendpage(), otherwise use sock_no_sendpage to handle this page. Signed-off-by: Coly Li Cc: Chaitanya Kulkarni Cc: Christoph Hellwig Cc: Hannes Reinecke Cc: Jan Kara Cc: Jens Axboe Cc: Mikhail Skorzhinskii Cc: Philipp Reisner Cc: Sagi Grimberg Cc: Vlastimil Babka Cc: stable@vger.kernel.org --- drivers/nvme/host/tcp.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index 62fbaecdc960..902fe742762b 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -912,12 +912,11 @@ static int nvme_tcp_try_send_data(struct nvme_tcp_request *req) else flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST; - /* can't zcopy slab pages */ - if (unlikely(PageSlab(page))) { - ret = sock_no_sendpage(queue->sock, page, offset, len, + if (sendpage_ok(page)) { + ret = kernel_sendpage(queue->sock, page, offset, len, flags); } else { - ret = kernel_sendpage(queue->sock, page, offset, len, + ret = sock_no_sendpage(queue->sock, page, offset, len, flags); } if (ret <= 0)