From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 2795BA04B1; Thu, 5 Nov 2020 10:04:34 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id F1F757CAE; Thu, 5 Nov 2020 10:04:32 +0100 (CET) Received: from mx0b-0016f401.pphosted.com (mx0a-0016f401.pphosted.com [67.231.148.174]) by dpdk.org (Postfix) with ESMTP id 068CC6CAC for ; Thu, 5 Nov 2020 10:04:31 +0100 (CET) Received: from pps.filterd (m0045849.ppops.net [127.0.0.1]) by mx0a-0016f401.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 0A5900PS028629; Thu, 5 Nov 2020 01:04:30 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=marvell.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=pfpt0220; bh=mtJkplKQGMekQ4A0g0HtsqBm+Dnu2TMJXB3kqwJ0xj8=; b=a/2VwUxW92Cme2jB5xSXtYOIh87pE/9wIFxB+tbC2SrM8Vh4BAxEPb2Q3aHH+7xEv6np 1lSNI23oadWPD4BuxZ9WPP0andU9fvkv1zlOnTDXsGSX48RY8WUTw9lx5ouImnTRbMRm mrAC3U6JAtYuvJ2fOcF2wQJWl1HWnBKs/4Xgzm0S2tIE40/zqyZNG2OdXi46AIRrKxXo ipwgSura4/gKjbZ3J7LnXmkx9KpIH+OVcoc7CpctkWNXWK8Hl2lkBxFuzu5008VdEh5H omRI+lAUdCUa61P4gNqSNI+2ZxQXD7UqnPsx4uVq//YycOnCY14q/1TWXpjf/O8TEy2A Qg== Received: from sc-exch01.marvell.com ([199.233.58.181]) by mx0a-0016f401.pphosted.com with ESMTP id 34mbfcrndg-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT); Thu, 05 Nov 2020 01:04:30 -0800 Received: from DC5-EXCH02.marvell.com (10.69.176.39) by SC-EXCH01.marvell.com (10.93.176.81) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 5 Nov 2020 01:04:27 -0800 Received: from maili.marvell.com (10.69.176.80) by DC5-EXCH02.marvell.com (10.69.176.39) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Thu, 5 Nov 2020 01:04:27 -0800 Received: from hyd1588t430.marvell.com (unknown [10.29.52.204]) by maili.marvell.com (Postfix) with ESMTP id 1E6363F703F; Thu, 5 Nov 2020 01:04:25 -0800 (PST) From: Nithin Dabilpuram To: CC: , , Nithin Dabilpuram Date: Thu, 5 Nov 2020 14:34:20 +0530 Message-ID: <20201105090423.11954-1-ndabilpuram@marvell.com> X-Mailer: git-send-email 2.8.4 In-Reply-To: <20201012081106.10610-1-ndabilpuram@marvell.com> References: <20201012081106.10610-1-ndabilpuram@marvell.com> MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.312, 18.0.737 definitions=2020-11-05_05:2020-11-05, 2020-11-05 signatures=0 Subject: [dpdk-dev] [PATCH v2 0/3] fix issue with partial DMA unmap 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" Partial DMA unmap is not supported by VFIO type1 IOMMU in Linux. Though the return value is zero, the returned DMA unmap size is not same as expected size. So add test case and fix to both heap triggered DMA mapping and user triggered DMA mapping/unmapping. Refer vfio_dma_do_unmap() in drivers/vfio/vfio_iommu_type1.c Snippet of comment is below. /* * vfio-iommu-type1 (v1) - User mappings were coalesced together to * avoid tracking individual mappings. This means that the granularity * of the original mapping was lost and the user was allowed to attempt * to unmap any range. Depending on the contiguousness of physical * memory and page sizes supported by the IOMMU, arbitrary unmaps may * or may not have worked. We only guaranteed unmap granularity * matching the original mapping; even though it was untracked here, * the original mappings are reflected in IOMMU mappings. This * resulted in a couple unusual behaviors. First, if a range is not * able to be unmapped, ex. a set of 4k pages that was mapped as a * 2M hugepage into the IOMMU, the unmap ioctl returns success but with * a zero sized unmap. Also, if an unmap request overlaps the first * address of a hugepage, the IOMMU will unmap the entire hugepage. * This also returns success and the returned unmap size reflects the * actual size unmapped. * We attempt to maintain compatibility with this "v1" interface, but * we take control out of the hands of the IOMMU. Therefore, an unmap * request offset from the beginning of the original mapping will * return success with zero sized unmap. And an unmap request covering * the first iova of mapping will unmap the entire range. This behavior can be verified by using first patch and add return check for dma_unmap.size != len in vfio_type1_dma_mem_map() v2: - Reverted earlier commit that enables mergin contiguous mapping for IOVA as PA. (see 1/3) - Updated documentation about kernel dma mapping limits and vfio module parameter. - Moved vfio test to test_vfio.c and handled comments from Anatoly. Nithin Dabilpuram (3): vfio: revert changes for map contiguous areas in one go vfio: fix DMA mapping granularity for type1 iova as va test: add test case to validate VFIO DMA map/unmap app/test/meson.build | 1 + app/test/test_vfio.c | 103 +++++++++++++++++++++++++++++++++ doc/guides/linux_gsg/linux_drivers.rst | 10 ++++ lib/librte_eal/linux/eal_vfio.c | 93 ++++++++++++----------------- lib/librte_eal/linux/eal_vfio.h | 1 + 5 files changed, 151 insertions(+), 57 deletions(-) create mode 100644 app/test/test_vfio.c -- 2.8.4