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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham 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 75257C433E4 for ; Mon, 6 Jul 2020 00:30:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4E68120786 for ; Mon, 6 Jul 2020 00:30:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728400AbgGFAaT (ORCPT ); Sun, 5 Jul 2020 20:30:19 -0400 Received: from mga07.intel.com ([134.134.136.100]:32284 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728334AbgGFAaR (ORCPT ); Sun, 5 Jul 2020 20:30:17 -0400 IronPort-SDR: NPdvHupZdy6LTlXOpfTj3g+QDHt5PHC81guSnt/w655XuFNSV9cuiqNShoXQNbMuK5GzFOtQrv NXX+uBgIYX9w== X-IronPort-AV: E=McAfee;i="6000,8403,9673"; a="212331321" X-IronPort-AV: E=Sophos;i="5.75,318,1589266800"; d="scan'208";a="212331321" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jul 2020 17:30:16 -0700 IronPort-SDR: pHhb659F8hdUQyygF4paG1fQFF39d+fLmMVXuK8ZYni1jiD/59cLm5gbf+fJ+gW9zB75chJyum dbaNhrFpuWpw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,318,1589266800"; d="scan'208";a="266404962" Received: from allen-box.sh.intel.com ([10.239.159.139]) by fmsmga007.fm.intel.com with ESMTP; 05 Jul 2020 17:30:14 -0700 From: Lu Baolu To: iommu@lists.linux-foundation.org Cc: Joerg Roedel , Jacob Pan , Kevin Tian , Ashok Raj , Liu Yi L , linux-kernel@vger.kernel.org, Lu Baolu Subject: [PATCH v2 3/4] iommu/vt-d: Report page request faults for guest SVA Date: Mon, 6 Jul 2020 08:25:34 +0800 Message-Id: <20200706002535.9381-4-baolu.lu@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200706002535.9381-1-baolu.lu@linux.intel.com> References: <20200706002535.9381-1-baolu.lu@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org A pasid might be bound to a page table from a VM guest via the iommu ops.sva_bind_gpasid. In this case, when a DMA page fault is detected on the physical IOMMU, we need to inject the page fault request into the guest. After the guest completes handling the page fault, a page response need to be sent back via the iommu ops.page_response(). This adds support to report a page request fault. Any external module which is interested in handling this fault should regiester a notifier callback. Co-developed-by: Jacob Pan Signed-off-by: Jacob Pan Co-developed-by: Liu Yi L Signed-off-by: Liu Yi L Signed-off-by: Lu Baolu --- drivers/iommu/intel/svm.c | 99 ++++++++++++++++++++++++++++++++------- 1 file changed, 81 insertions(+), 18 deletions(-) diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c index c23167877b2b..08c58c2b1a06 100644 --- a/drivers/iommu/intel/svm.c +++ b/drivers/iommu/intel/svm.c @@ -815,6 +815,57 @@ static void intel_svm_drain_prq(struct device *dev, int pasid) } } +static int prq_to_iommu_prot(struct page_req_dsc *req) +{ + int prot = 0; + + if (req->rd_req) + prot |= IOMMU_FAULT_PERM_READ; + if (req->wr_req) + prot |= IOMMU_FAULT_PERM_WRITE; + if (req->exe_req) + prot |= IOMMU_FAULT_PERM_EXEC; + if (req->pm_req) + prot |= IOMMU_FAULT_PERM_PRIV; + + return prot; +} + +static int +intel_svm_prq_report(struct device *dev, struct page_req_dsc *desc) +{ + struct iommu_fault_event event; + u8 bus, devfn; + + memset(&event, 0, sizeof(struct iommu_fault_event)); + bus = PCI_BUS_NUM(desc->rid); + devfn = desc->rid & 0xff; + + /* Fill in event data for device specific processing */ + event.fault.type = IOMMU_FAULT_PAGE_REQ; + event.fault.prm.addr = desc->addr; + event.fault.prm.pasid = desc->pasid; + event.fault.prm.grpid = desc->prg_index; + event.fault.prm.perm = prq_to_iommu_prot(desc); + + /* + * Set last page in group bit if private data is present, + * page response is required as it does for LPIG. + */ + if (desc->lpig) + event.fault.prm.flags |= IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE; + if (desc->pasid_present) + event.fault.prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PASID_VALID; + if (desc->priv_data_present) { + event.fault.prm.flags |= IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE; + event.fault.prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PRIV_DATA; + memcpy(event.fault.prm.private_data, desc->priv_data, + sizeof(desc->priv_data)); + } + + return iommu_report_device_fault(dev, &event); +} + static irqreturn_t prq_event_thread(int irq, void *d) { struct intel_iommu *iommu = d; @@ -828,7 +879,7 @@ static irqreturn_t prq_event_thread(int irq, void *d) tail = dmar_readq(iommu->reg + DMAR_PQT_REG) & PRQ_RING_MASK; head = dmar_readq(iommu->reg + DMAR_PQH_REG) & PRQ_RING_MASK; while (head != tail) { - struct intel_svm_dev *sdev; + struct intel_svm_dev *sdev = NULL; struct vm_area_struct *vma; struct page_req_dsc *req; struct qi_desc resp; @@ -864,6 +915,20 @@ static irqreturn_t prq_event_thread(int irq, void *d) } } + if (!sdev || sdev->sid != req->rid) { + struct intel_svm_dev *t; + + sdev = NULL; + rcu_read_lock(); + list_for_each_entry_rcu(t, &svm->devs, list) { + if (t->sid == req->rid) { + sdev = t; + break; + } + } + rcu_read_unlock(); + } + result = QI_RESP_INVALID; /* Since we're using init_mm.pgd directly, we should never take * any faults on kernel addresses. */ @@ -874,6 +939,17 @@ static irqreturn_t prq_event_thread(int irq, void *d) if (!is_canonical_address(address)) goto bad_req; + /* + * If prq is to be handled outside iommu driver via receiver of + * the fault notifiers, we skip the page response here. + */ + if (svm->flags & SVM_FLAG_GUEST_MODE) { + if (sdev && !intel_svm_prq_report(sdev->dev, req)) + goto prq_advance; + else + goto bad_req; + } + /* If the mm is already defunct, don't handle faults. */ if (!mmget_not_zero(svm->mm)) goto bad_req; @@ -892,24 +968,10 @@ static irqreturn_t prq_event_thread(int irq, void *d) goto invalid; result = QI_RESP_SUCCESS; - invalid: +invalid: mmap_read_unlock(svm->mm); mmput(svm->mm); - bad_req: - /* Accounting for major/minor faults? */ - rcu_read_lock(); - list_for_each_entry_rcu(sdev, &svm->devs, list) { - if (sdev->sid == req->rid) - break; - } - /* Other devices can go away, but the drivers are not permitted - * to unbind while any page faults might be in flight. So it's - * OK to drop the 'lock' here now we have it. */ - rcu_read_unlock(); - - if (WARN_ON(&sdev->list == &svm->devs)) - sdev = NULL; - +bad_req: if (sdev && sdev->ops && sdev->ops->fault_cb) { int rwxp = (req->rd_req << 3) | (req->wr_req << 2) | (req->exe_req << 1) | (req->pm_req); @@ -920,7 +982,7 @@ static irqreturn_t prq_event_thread(int irq, void *d) and these can be NULL. Do not use them below this point! */ sdev = NULL; svm = NULL; - no_pasid: +no_pasid: if (req->lpig || req->priv_data_present) { /* * Per VT-d spec. v3.0 ch7.7, system software must @@ -945,6 +1007,7 @@ static irqreturn_t prq_event_thread(int irq, void *d) resp.qw3 = 0; qi_submit_sync(iommu, &resp, 1, 0); } +prq_advance: head = (head + sizeof(*req)) & PRQ_RING_MASK; } -- 2.17.1