From patchwork Tue Jan 29 08:43:37 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 10785789 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 82368922 for ; Tue, 29 Jan 2019 08:43:49 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6980B28751 for ; Tue, 29 Jan 2019 08:43:49 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5A5802AB9E; Tue, 29 Jan 2019 08:43:49 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8C2392BB82 for ; Tue, 29 Jan 2019 08:43:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727290AbfA2Inr (ORCPT ); Tue, 29 Jan 2019 03:43:47 -0500 Received: from 8bytes.org ([81.169.241.247]:35504 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725298AbfA2Inq (ORCPT ); Tue, 29 Jan 2019 03:43:46 -0500 Received: by theia.8bytes.org (Postfix, from userid 1000) id 574DD1F1; Tue, 29 Jan 2019 09:43:44 +0100 (CET) From: Joerg Roedel To: "Michael S . Tsirkin" , Jason Wang , Konrad Rzeszutek Wilk , Christoph Hellwig Cc: Jens Axboe , virtualization@lists.linux-foundation.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, jfehlig@suse.com, jon.grimm@amd.com, brijesh.singh@amd.com, joro@8bytes.org, jroedel@suse.de Subject: [PATCH 0/5 v4] Fix virtio-blk issue with SWIOTLB Date: Tue, 29 Jan 2019 09:43:37 +0100 Message-Id: <20190129084342.26030-1-joro@8bytes.org> X-Mailer: git-send-email 2.17.1 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Hi, here is the fourth version of this patch-set. Previous versions can be found here: V1: https://lore.kernel.org/lkml/20190110134433.15672-1-joro@8bytes.org/ V2: https://lore.kernel.org/lkml/20190115132257.6426-1-joro@8bytes.org/ V3: https://lore.kernel.org/lkml/20190123163049.24863-1-joro@8bytes.org/ The problem solved here is a limitation of the SWIOTLB implementation, which does not support allocations larger than 256kb. When the virtio-blk driver tries to read/write a block larger than that, the allocation of the dma-handle fails and an IO error is reported. For all changes to v3, a diff to v3 of the patch-set is at the end of this email. Please review. Thanks, Joerg Joerg Roedel (5): swiotlb: Introduce swiotlb_max_mapping_size() swiotlb: Add is_swiotlb_active() function dma: Introduce dma_max_mapping_size() virtio: Introduce virtio_max_dma_size() virtio-blk: Consider virtio_max_dma_size() for maximum segment size Documentation/DMA-API.txt | 8 ++++++++ drivers/block/virtio_blk.c | 10 ++++++---- drivers/virtio/virtio_ring.c | 10 ++++++++++ include/linux/dma-mapping.h | 16 ++++++++++++++++ include/linux/swiotlb.h | 11 +++++++++++ include/linux/virtio.h | 2 ++ kernel/dma/direct.c | 11 +++++++++++ kernel/dma/swiotlb.c | 14 ++++++++++++++ 8 files changed, 78 insertions(+), 4 deletions(-) diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt index e133ccd60228..acfe3d0f78d1 100644 --- a/Documentation/DMA-API.txt +++ b/Documentation/DMA-API.txt @@ -195,6 +195,14 @@ Requesting the required mask does not alter the current mask. If you wish to take advantage of it, you should issue a dma_set_mask() call to set the mask to the value returned. +:: + + size_t + dma_direct_max_mapping_size(struct device *dev); + +Returns the maximum size of a mapping for the device. The size parameter +of the mapping functions like dma_map_single(), dma_map_page() and +others should not be larger than the returned value. Part Id - Streaming DMA mappings -------------------------------- diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index 5c087d330b4b..e9e786b4b598 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -62,7 +62,7 @@ extern void swiotlb_tbl_sync_single(struct device *hwdev, extern int swiotlb_dma_supported(struct device *hwdev, u64 mask); -extern size_t swiotlb_max_mapping_size(struct device *dev); +size_t swiotlb_max_mapping_size(struct device *dev); bool is_swiotlb_active(void); #ifdef CONFIG_SWIOTLB diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 9fbd075081d9..c873f9cc2146 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -670,5 +670,9 @@ size_t swiotlb_max_mapping_size(struct device *dev) bool is_swiotlb_active(void) { - return !no_iotlb_memory; + /* + * When SWIOTLB is initialized, even if io_tlb_start points to physical + * address zero, io_tlb_end surely doesn't. + */ + return io_tlb_end != 0; }