From patchwork Mon Oct 5 17:36:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Diana Madalina Craciun X-Patchwork-Id: 11817099 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 3B06B112E for ; Mon, 5 Oct 2020 17:37:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2CEF720853 for ; Mon, 5 Oct 2020 17:37:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728991AbgJERhW (ORCPT ); Mon, 5 Oct 2020 13:37:22 -0400 Received: from inva021.nxp.com ([92.121.34.21]:44692 "EHLO inva021.nxp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727344AbgJERhB (ORCPT ); Mon, 5 Oct 2020 13:37:01 -0400 Received: from inva021.nxp.com (localhost [127.0.0.1]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id B416A20159F; Mon, 5 Oct 2020 19:36:59 +0200 (CEST) Received: from inva024.eu-rdc02.nxp.com (inva024.eu-rdc02.nxp.com [134.27.226.22]) by inva021.eu-rdc02.nxp.com (Postfix) with ESMTP id A76C62015AB; Mon, 5 Oct 2020 19:36:59 +0200 (CEST) Received: from fsr-ub1864-111.ea.freescale.net (fsr-ub1864-111.ea.freescale.net [10.171.82.141]) by inva024.eu-rdc02.nxp.com (Postfix) with ESMTP id 58A942032B; Mon, 5 Oct 2020 19:36:59 +0200 (CEST) From: Diana Craciun To: Alex Williamson , kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org, bharatb.linux@gmail.com, laurentiu.tudor@nxp.com, Diana Craciun , Bharat Bhushan Subject: [PATCH v6 05/10] vfio/fsl-mc: Allow userspace to MMAP fsl-mc device MMIO regions Date: Mon, 5 Oct 2020 20:36:49 +0300 Message-Id: <20201005173654.31773-6-diana.craciun@oss.nxp.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20201005173654.31773-1-diana.craciun@oss.nxp.com> References: <20201005173654.31773-1-diana.craciun@oss.nxp.com> X-Virus-Scanned: ClamAV using ClamSMTP Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Allow userspace to mmap device regions for direct access of fsl-mc devices. Signed-off-by: Bharat Bhushan Signed-off-by: Diana Craciun Reviewed-by: Eric Auger --- drivers/vfio/fsl-mc/vfio_fsl_mc.c | 68 ++++++++++++++++++++++++++++++- 1 file changed, 66 insertions(+), 2 deletions(-) diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c index 05dace5ddc2c..55190a2730fb 100644 --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c @@ -30,11 +30,20 @@ static int vfio_fsl_mc_regions_init(struct vfio_fsl_mc_device *vdev) for (i = 0; i < count; i++) { struct resource *res = &mc_dev->regions[i]; + int no_mmap = is_fsl_mc_bus_dprc(mc_dev); vdev->regions[i].addr = res->start; vdev->regions[i].size = resource_size(res); - vdev->regions[i].flags = 0; vdev->regions[i].type = mc_dev->regions[i].flags & IORESOURCE_BITS; + /* + * Only regions addressed with PAGE granularity may be + * MMAPed securely. + */ + if (!no_mmap && !(vdev->regions[i].addr & ~PAGE_MASK) && + !(vdev->regions[i].size & ~PAGE_MASK)) + vdev->regions[i].flags |= + VFIO_REGION_INFO_FLAG_MMAP; + } return 0; @@ -163,9 +172,64 @@ static ssize_t vfio_fsl_mc_write(void *device_data, const char __user *buf, return -EINVAL; } +static int vfio_fsl_mc_mmap_mmio(struct vfio_fsl_mc_region region, + struct vm_area_struct *vma) +{ + u64 size = vma->vm_end - vma->vm_start; + u64 pgoff, base; + u8 region_cacheable; + + pgoff = vma->vm_pgoff & + ((1U << (VFIO_FSL_MC_OFFSET_SHIFT - PAGE_SHIFT)) - 1); + base = pgoff << PAGE_SHIFT; + + if (region.size < PAGE_SIZE || base + size > region.size) + return -EINVAL; + + region_cacheable = (region.type & FSL_MC_REGION_CACHEABLE) && + (region.type & FSL_MC_REGION_SHAREABLE); + if (!region_cacheable) + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + + vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff; + + return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, + size, vma->vm_page_prot); +} + static int vfio_fsl_mc_mmap(void *device_data, struct vm_area_struct *vma) { - return -EINVAL; + struct vfio_fsl_mc_device *vdev = device_data; + struct fsl_mc_device *mc_dev = vdev->mc_dev; + int index; + + index = vma->vm_pgoff >> (VFIO_FSL_MC_OFFSET_SHIFT - PAGE_SHIFT); + + if (vma->vm_end < vma->vm_start) + return -EINVAL; + if (vma->vm_start & ~PAGE_MASK) + return -EINVAL; + if (vma->vm_end & ~PAGE_MASK) + return -EINVAL; + if (!(vma->vm_flags & VM_SHARED)) + return -EINVAL; + if (index >= mc_dev->obj_desc.region_count) + return -EINVAL; + + if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP)) + return -EINVAL; + + if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ) + && (vma->vm_flags & VM_READ)) + return -EINVAL; + + if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE) + && (vma->vm_flags & VM_WRITE)) + return -EINVAL; + + vma->vm_private_data = mc_dev; + + return vfio_fsl_mc_mmap_mmio(vdev->regions[index], vma); } static const struct vfio_device_ops vfio_fsl_mc_ops = {