From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 60EDFC4320A for ; Wed, 18 Aug 2021 08:22:34 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BB9B460560 for ; Wed, 18 Aug 2021 08:22:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org BB9B460560 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4GqLVc2S0Vz3dD7 for ; Wed, 18 Aug 2021 18:22:32 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.alibaba.com (client-ip=115.124.30.44; helo=out30-44.freemail.mail.aliyun.com; envelope-from=xianting.tian@linux.alibaba.com; receiver=) Received: from out30-44.freemail.mail.aliyun.com (out30-44.freemail.mail.aliyun.com [115.124.30.44]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4GqLTj2bq1z30LB for ; Wed, 18 Aug 2021 18:21:43 +1000 (AEST) X-Alimail-AntiSpam: AC=PASS; BC=-1|-1; BR=01201311R121e4; CH=green; DM=||false|; DS=||; FP=0|-1|-1|-1|0|-1|-1|-1; HT=e01e04394; MF=xianting.tian@linux.alibaba.com; NM=1; PH=DS; RN=10; SR=0; TI=SMTPD_---0Ujfv4hp_1629274884; Received: from localhost(mailfrom:xianting.tian@linux.alibaba.com fp:SMTPD_---0Ujfv4hp_1629274884) by smtp.aliyun-inc.com(127.0.0.1); Wed, 18 Aug 2021 16:21:25 +0800 From: Xianting Tian To: gregkh@linuxfoundation.org, jirislaby@kernel.org, amit@kernel.org, arnd@arndb.de, osandov@fb.com Subject: [PATCH v8 0/3] make hvc pass dma capable memory to its backend Date: Wed, 18 Aug 2021 16:21:19 +0800 Message-Id: <20210818082122.166881-1-xianting.tian@linux.alibaba.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Xianting Tian , shile.zhang@linux.alibaba.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Dear all, This patch series make hvc framework pass DMA capable memory to put_chars() of hvc backend(eg, virtio-console), and revert commit c4baad5029 ("virtio-console: avoid DMA from stack”) V1 virtio-console: avoid DMA from vmalloc area https://lkml.org/lkml/2021/7/27/494 For v1 patch, Arnd Bergmann suggests to fix the issue in the first place: Make hvc pass DMA capable memory to put_chars() The fix suggestion is included in v2. V2 [PATCH 1/2] tty: hvc: pass DMA capable memory to put_chars() https://lkml.org/lkml/2021/8/1/8 [PATCH 2/2] virtio-console: remove unnecessary kmemdup() https://lkml.org/lkml/2021/8/1/9 For v2 patch, Arnd Bergmann suggests to make new buf part of the hvc_struct structure, and fix the compile issue. The fix suggestion is included in v3. V3 [PATCH v3 1/2] tty: hvc: pass DMA capable memory to put_chars() https://lkml.org/lkml/2021/8/3/1347 [PATCH v3 2/2] virtio-console: remove unnecessary kmemdup() https://lkml.org/lkml/2021/8/3/1348 For v3 patch, Jiri Slaby suggests to make 'char c[N_OUTBUF]' part of hvc_struct, and make 'hp->outbuf' aligned and use struct_size() to calculate the size of hvc_struct. The fix suggestion is included in v4. V4 [PATCH v4 0/2] make hvc pass dma capable memory to its backend https://lkml.org/lkml/2021/8/5/1350 [PATCH v4 1/2] tty: hvc: pass DMA capable memory to put_chars() https://lkml.org/lkml/2021/8/5/1351 [PATCH v4 2/2] virtio-console: remove unnecessary kmemdup() https://lkml.org/lkml/2021/8/5/1352 For v4 patch, Arnd Bergmann suggests to introduce another array(cons_outbuf[]) for the buffer pointers next to the cons_ops[] and vtermnos[] arrays. This fix included in this v5 patch. V5 Arnd Bergmann suggests to use "L1_CACHE_BYTES" as dma alignment, use 'sizeof(long)' as dma alignment is wrong. fix it in v6. V6 It contains coding error, fix it in v7 and it worked normally according to test result. V7 Greg KH suggests to add test and code review developer, Jiri Slaby suggests to use lockless buffer and fix dma alignment in separate patch. fix above things in v8. drivers/tty/hvc/hvc_console.c | 27 ++++++++++++--------------- drivers/tty/hvc/hvc_console.h | 16 ++++++++++++++-- drivers/tty/hvc/hvc_console.h | 16 ++++++++++++-- 3 file changed