From patchwork Sun Mar 10 08:27:59 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shahaf Shuler X-Patchwork-Id: 51017 X-Patchwork-Delegate: thomas@monjalon.net Return-Path: X-Original-To: patchwork@dpdk.org Delivered-To: patchwork@dpdk.org Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 62D974C9D; Sun, 10 Mar 2019 09:28:28 +0100 (CET) Received: from mellanox.co.il (mail-il-dmz.mellanox.com [193.47.165.129]) by dpdk.org (Postfix) with ESMTP id BDBD74C8D for ; Sun, 10 Mar 2019 09:28:23 +0100 (CET) Received: from Internal Mail-Server by MTLPINE1 (envelope-from shahafs@mellanox.com) with ESMTPS (AES256-SHA encrypted); 10 Mar 2019 10:28:18 +0200 Received: from unicorn01.mtl.labs.mlnx. (unicorn01.mtl.labs.mlnx [10.7.12.62]) by labmailer.mlnx (8.13.8/8.13.8) with ESMTP id x2A8SI5A029045; Sun, 10 Mar 2019 10:28:18 +0200 From: Shahaf Shuler To: anatoly.burakov@intel.com, yskoh@mellanox.com, thomas@monjalon.net, ferruh.yigit@intel.com, nhorman@tuxdriver.com, gaetan.rivet@6wind.com Cc: dev@dpdk.org Date: Sun, 10 Mar 2019 10:27:59 +0200 Message-Id: X-Mailer: git-send-email 2.12.0 In-Reply-To: References: Subject: [dpdk-dev] [PATCH v4 2/6] vfio: don't fail to DMA map if memory is already mapped X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Currently vfio DMA map function will fail in case the same memory segment is mapped twice. This is too strict, as this is not an error to map the same memory twice. Instead, use the kernel return value to detect such state and have the DMA function to return as successful. For type1 mapping the kernel driver returns EEXISTS. For spapr mapping EBUSY is returned since kernel 4.10. Signed-off-by: Shahaf Shuler Acked-by: Anatoly Burakov --- lib/librte_eal/linuxapp/eal/eal_vfio.c | 32 +++++++++++++++++++++++++---- 1 file changed, 28 insertions(+), 4 deletions(-) diff --git a/lib/librte_eal/linuxapp/eal/eal_vfio.c b/lib/librte_eal/linuxapp/eal/eal_vfio.c index 9adbda8bb7..d0a0f9c16f 100644 --- a/lib/librte_eal/linuxapp/eal/eal_vfio.c +++ b/lib/librte_eal/linuxapp/eal/eal_vfio.c @@ -1264,9 +1264,21 @@ vfio_type1_dma_mem_map(int vfio_container_fd, uint64_t vaddr, uint64_t iova, ret = ioctl(vfio_container_fd, VFIO_IOMMU_MAP_DMA, &dma_map); if (ret) { - RTE_LOG(ERR, EAL, " cannot set up DMA remapping, error %i (%s)\n", - errno, strerror(errno)); + /** + * In case the mapping was already done EEXIST will be + * returned from kernel. + */ + if (errno == EEXIST) { + RTE_LOG(DEBUG, EAL, + " Memory segment is allready mapped," + " skipping"); + } else { + RTE_LOG(ERR, EAL, + " cannot set up DMA remapping," + " error %i (%s)\n", + errno, strerror(errno)); return -1; + } } } else { memset(&dma_unmap, 0, sizeof(dma_unmap)); @@ -1325,9 +1337,21 @@ vfio_spapr_dma_do_map(int vfio_container_fd, uint64_t vaddr, uint64_t iova, ret = ioctl(vfio_container_fd, VFIO_IOMMU_MAP_DMA, &dma_map); if (ret) { - RTE_LOG(ERR, EAL, " cannot set up DMA remapping, error %i (%s)\n", - errno, strerror(errno)); + /** + * In case the mapping was already done EBUSY will be + * returned from kernel. + */ + if (errno == EBUSY) { + RTE_LOG(DEBUG, EAL, + " Memory segment is allready mapped," + " skipping"); + } else { + RTE_LOG(ERR, EAL, + " cannot set up DMA remapping," + " error %i (%s)\n", errno, + strerror(errno)); return -1; + } } } else {