// SPDX-License-Identifier: GPL-2.0-only /* * Copyright © 2015 Intel Corporation. * * Authors: David Woodhouse */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "pasid.h" static irqreturn_t prq_event_thread(int irq, void *d); static void intel_svm_drain_prq(struct device *dev, u32 pasid); #define PRQ_ORDER 0 int intel_svm_enable_prq(struct intel_iommu *iommu) { struct page *pages; int irq, ret; pages = alloc_pages(GFP_KERNEL | __GFP_ZERO, PRQ_ORDER); if (!pages) { pr_warn("IOMMU: %s: Failed to allocate page request queue\n", iommu->name); return -ENOMEM; } iommu->prq = page_address(pages); irq = dmar_alloc_hwirq(DMAR_UNITS_SUPPORTED + iommu->seq_id, iommu->node, iommu); if (irq <= 0) { pr_err("IOMMU: %s: Failed to create IRQ vector for page request queue\n", iommu->name); ret = -EINVAL; err: free_pages((unsigned long)iommu->prq, PRQ_ORDER); iommu->prq = NULL; return ret; } iommu->pr_irq = irq; snprintf(iommu->prq_name, sizeof(iommu->prq_name), "dmar%d-prq", iommu->seq_id); ret = request_threaded_irq(irq, NULL, prq_event_thread, IRQF_ONESHOT, iommu->prq_name, iommu); if (ret) { pr_err("IOMMU: %s: Failed to request IRQ for page request queue\n", iommu->name); dmar_free_hwirq(irq); iommu->pr_irq = 0; goto err; } dmar_writeq(iommu->reg + DMAR_PQH_REG, 0ULL); dmar_writeq(iommu->reg + DMAR_PQT_REG, 0ULL); dmar_writeq(iommu->reg + DMAR_PQA_REG, virt_to_phys(iommu->prq) | PRQ_ORDER); init_completion(&iommu->prq_complete); return 0; } int intel_svm_finish_prq(struct intel_iommu *iommu) { dmar_writeq(iommu->reg + DMAR_PQH_REG, 0ULL); dmar_writeq(iommu->reg + DMAR_PQT_REG, 0ULL); dmar_writeq(iommu->reg + DMAR_PQA_REG, 0ULL); if (iommu->pr_irq) { free_irq(iommu->pr_irq, iommu); dmar_free_hwirq(iommu->pr_irq); iommu->pr_irq = 0; } free_pages((unsigned long)iommu->prq, PRQ_ORDER); iommu->prq = NULL; return 0; } static inline bool intel_svm_capable(struct intel_iommu *iommu) { return iommu->flags & VTD_FLAG_SVM_CAPABLE; } void intel_svm_check(struct intel_iommu *iommu) { if (!pasid_supported(iommu)) return; if (cpu_feature_enabled(X86_FEATURE_GBPAGES) && !cap_fl1gp_support(iommu->cap)) { pr_err("%s SVM disabled, incompatible 1GB page capability\n", iommu->name); return; } if (cpu_feature_enabled(X86_FEATURE_LA57) && !cap_5lp_support(iommu->cap)) { pr_err("%s SVM disabled, incompatible paging mode\n", iommu->name); return; } iommu->flags |= VTD_FLAG_SVM_CAPABLE; } static void __flush_svm_range_dev(struct intel_svm *svm, struct intel_svm_dev *sdev, unsigned long address, unsigned long pages, int ih) { struct device_domain_info *info = get_domain_info(sdev->dev); if (WARN_ON(!pages)) return; qi_flush_piotlb(sdev->iommu, sdev->did, svm->pasid, address, pages, ih); if (info->ats_enabled) qi_flush_dev_iotlb_pasid(sdev->iommu, sdev->sid, info->pfsid, svm->pasid, sdev->qdep, address, order_base_2(pages)); } static void intel_flush_svm_range_dev(struct intel_svm *svm, struct intel_svm_dev *sdev, unsigned long address, unsigned long pages, int ih) { unsigned long shift = ilog2(__roundup_pow_of_two(pages)); unsigned long align = (1ULL << (VTD_PAGE_SHIFT + shift)); unsigned long start = ALIGN_DOWN(address, align); unsigned long end = ALIGN(address + (pages << VTD_PAGE_SHIFT), align); while (start < end) { __flush_svm_range_dev(svm, sdev, start, align >> VTD_PAGE_SHIFT, ih); start += align; } } static void intel_flush_svm_range(struct intel_svm *svm, unsigned long address, unsigned long pages, int ih) { struct intel_svm_dev *sdev; rcu_read_lock(); list_for_each_entry_rcu(sdev, &svm->devs, list) intel_flush_svm_range_dev(svm, sdev, address, pages, ih); rcu_read_unlock(); } /* Pages have been freed at this point */ static void intel_invalidate_range(struct mmu_notifier *mn, struct mm_struct *mm, unsigned long start, unsigned long end) { struct intel_svm *svm = container_of(mn, struct intel_svm, notifier); intel_flush_svm_range(svm, start, (end - start + PAGE_SIZE - 1) >> VTD_PAGE_SHIFT, 0); } static void intel_mm_release(struct mmu_notifier *mn, struct mm_struct *mm) { struct intel_svm *svm = container_of(mn, struct intel_svm, notifier); struct intel_svm_dev *sdev; /* This might end up being called from exit_mmap(), *before* the page * tables are cleared. And __mmu_notifier_release() will delete us from * the list of notifiers so that our invalidate_range() callback doesn't * get called when the page tables are cleared. So we need to protect * against hardware accessing those page tables. * * We do it by clearing the entry in the PASID table and then flushing * the IOTLB and the PASID table caches. This might upset hardware; * perhaps we'll want to point the PASID to a dummy PGD (like the zero * page) so that we end up taking a fault that the hardware really * *has* to handle gracefully without affecting other processes. */ rcu_read_lock(); list_for_each_entry_rcu(sdev, &svm->devs, list) intel_pasid_tear_down_entry(sdev->iommu, sdev->dev, svm->pasid, true); rcu_read_unlock(); } static const struct mmu_notifier_ops intel_mmuops = { .release = intel_mm_release, .invalidate_range = intel_invalidate_range, }; static DEFINE_MUTEX(pasid_mutex); static LIST_HEAD(global_svm_list); #define for_each_svm_dev(sdev, svm, d) \ list_for_each_entry((sdev), &(svm)->devs, list) \ if ((d) != (sdev)->dev) {} else static int pasid_to_svm_sdev(struct device *dev, unsigned int pasid, struct intel_svm **rsvm, struct intel_svm_dev **rsdev) { struct intel_svm_dev *d, *sdev = NULL; struct intel_svm *svm; /* The caller should hold the pasid_mutex lock */ if (WARN_ON(!mutex_is_locked(&pasid_mutex))) return -EINVAL; if (pasid == INVALID_IOASID || pasid >= PASID_MAX) return -EINVAL; svm = ioasid_find(NULL, pasid, NULL); if (IS_ERR(svm)) return PTR_ERR(svm); if (!svm) goto out; /* * If we found svm for the PASID, there must be at least one device * bond. */ if (WARN_ON(list_empty(&svm->devs))) return -EINVAL; rcu_read_lock(); list_for_each_entry_rcu(d, &svm->devs, list) { if (d->dev == dev) { sdev = d; break; } } rcu_read_unlock(); out: *rsvm = svm; *rsdev = sdev; return 0; } int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev, struct iommu_gpasid_bind_data *data) { struct intel_iommu *iommu = device_to_iommu(dev, NULL, NULL); struct intel_svm_dev *sdev = NULL; struct dmar_domain *dmar_domain; struct device_domain_info *info; struct intel_svm *svm = NULL; unsigned long iflags; int ret = 0; if (WARN_ON(!iommu) || !data) return -EINVAL; if (data->format != IOMMU_PASID_FORMAT_INTEL_VTD) return -EINVAL; /* IOMMU core ensures argsz is more than the start of the union */ if (data->argsz < offsetofend(struct iommu_gpasid_bind_data, vendor.vtd)) return -EINVAL; /* Make sure no undefined flags are used in vendor data */ if (data->vendor.vtd.flags & ~(IOMMU_SVA_VTD_GPASID_LAST - 1)) return -EINVAL; if (!dev_is_pci(dev)) return -ENOTSUPP; /* VT-d supports devices with full 20 bit PASIDs only */ if (pci_max_pasids(to_pci_dev(dev)) != PASID_MAX) return -EINVAL; /* * We only check host PASID range, we have no knowledge to check * guest PASID range. */ if (data->hpasid <= 0 || data->hpasid >= PASID_MAX) return -EINVAL; info = get_domain_info(dev); if (!info) return -EINVAL; dmar_domain = to_dmar_domain(domain); mutex_lock(&pasid_mutex); ret = pasid_to_svm_sdev(dev, data->hpasid, &svm, &sdev); if (ret) goto out; if (sdev) { /* * Do not allow multiple bindings of the same device-PASID since * there is only one SL page tables per PASID. We may revisit * once sharing PGD across domains are supported. */ dev_warn_ratelimited(dev, "Already bound with PASID %u\n", svm->pasid); ret = -EBUSY; goto out; } if (!svm) { /* We come here when PASID has never been bond to a device. */ svm = kzalloc(sizeof(*svm), GFP_KERNEL); if (!svm) { ret = -ENOMEM; goto out; } /* REVISIT: upper layer/VFIO can track host process that bind * the PASID. ioasid_set = mm might be sufficient for vfio to * check pasid VMM ownership. We can drop the following line * once VFIO and IOASID set check is in place. */ svm->mm = get_task_mm(current); svm->pasid = data->hpasid; if (data->flags & IOMMU_SVA_GPASID_VAL) { svm->gpasid = data->gpasid; svm->flags |= SVM_FLAG_GUEST_PASID; } ioasid_set_data(data->hpasid, svm); INIT_LIST_HEAD_RCU(&svm->devs); mmput(svm->mm); } sdev = kzalloc(sizeof(*sdev), GFP_KERNEL); if (!sdev) { ret = -ENOMEM; goto out; } sdev->dev = dev; sdev->sid = PCI_DEVID(info->bus, info->devfn); sdev->iommu = iommu; /* Only count users if device has aux domains */ if (iommu_dev_feature_enabled(dev, IOMMU_DEV_FEAT_AUX)) sdev->users = 1; /* Set up device context entry for PASID if not enabled already */ ret = intel_iommu_enable_pasid(iommu, sdev->dev); if (ret) { dev_err_ratelimited(dev, "Failed to enable PASID capability\n"); kfree(sdev); goto out; } /* * PASID table is per device for better security. Therefore, for * each bind of a new device even with an existing PASID, we need to * call the nested mode setup function here. */ spin_lock_irqsave(&iommu->lock, iflags); ret = intel_pasid_setup_nested(iommu, dev, (pgd_t *)(uintptr_t)data->gpgd, data->hpasid, &data->vendor.vtd, dmar_domain, data->addr_width); spin_unlock_irqrestore(&iommu->lock, iflags); if (ret) { dev_err_ratelimited(dev, "Failed to set up PASID %llu in nested mode, Err %d\n", data->hpasid, ret); /* * PASID entry should be in cleared state if nested mode * set up failed. So we only need to clear IOASID tracking * data such that free call will succeed. */ kfree(sdev); goto out; } svm->flags |= SVM_FLAG_GUEST_MODE; init_rcu_head(&sdev->rcu); list_add_rcu(&sdev->list, &svm->devs); out: if (!IS_ERR_OR_NULL(svm) && list_empty(&svm->devs)) { ioasid_set_data(data->hpasid, NULL); kfree(svm); } mutex_unlock(&pasid_mutex); return ret; } int intel_svm_unbind_gpasid(struct device *dev, u32 pasid) { struct intel_iommu *iommu = device_to_iommu(dev, NULL, NULL); struct intel_svm_dev *sdev; struct intel_svm *svm; int ret; if (WARN_ON(!iommu)) return -EINVAL; mutex_lock(&pasid_mutex); ret = pasid_to_svm_sdev(dev, pasid, &svm, &sdev); if (ret) goto out; if (sdev) { if (iommu_dev_feature_enabled(dev, IOMMU_DEV_FEAT_AUX)) sdev->users--; if (!sdev->users) { list_del_rcu(&sdev->list); intel_pasid_tear_down_entry(iommu, dev, svm->pasid, false); intel_svm_drain_prq(dev, svm->pasid); kfree_rcu(sdev, rcu); if (list_empty(&svm->devs)) { /* * We do not free the IOASID here in that * IOMMU driver did not allocate it. * Unlike native SVM, IOASID for guest use was * allocated prior to the bind call. * In any case, if the free call comes before * the unbind, IOMMU driver will get notified * and perform cleanup. */ ioasid_set_data(pasid, NULL); kfree(svm); } } } out: mutex_unlock(&pasid_mutex); return ret; } static void _load_pasid(void *unused) { update_pasid(); } static void load_pasid(struct mm_struct *mm, u32 pasid) { mutex_lock(&mm->context.lock); /* Synchronize with READ_ONCE in update_pasid(). */ smp_store_release(&mm->pasid, pasid); /* Update PASID MSR on all CPUs running the mm's tasks. */ on_each_cpu_mask(mm_cpumask(mm), _load_pasid, NULL, true); mutex_unlock(&mm->context.lock); } /* Caller must hold pasid_mutex, mm reference */ static int intel_svm_bind_mm(struct device *dev, unsigned int flags, struct svm_dev_ops *ops, struct mm_struct *mm, struct intel_svm_dev **sd) { struct intel_iommu *iommu = device_to_iommu(dev, NULL, NULL); struct device_domain_info *info; struct intel_svm_dev *sdev; struct intel_svm *svm = NULL; unsigned long iflags; int pasid_max; int ret; if (!iommu || dmar_disabled) return -EINVAL; if (!intel_svm_capable(iommu)) return -ENOTSUPP; if (dev_is_pci(dev)) { pasid_max = pci_max_pasids(to_pci_dev(dev)); if (pasid_max < 0) return -EINVAL; } else pasid_max = 1 << 20; /* Bind supervisor PASID shuld have mm = NULL */ if (flags & SVM_FLAG_SUPERVISOR_MODE) { if (!ecap_srs(iommu->ecap) || mm) { pr_err("Supervisor PASID with user provided mm.\n"); return -EINVAL; } } if (!(flags & SVM_FLAG_PRIVATE_PASID)) { struct intel_svm *t; list_for_each_entry(t, &global_svm_list, list) { if (t->mm != mm || (t->flags & SVM_FLAG_PRIVATE_PASID)) continue; svm = t; if (svm->pasid >= pasid_max) { dev_warn(dev, "Limited PASID width. Cannot use existing PASID %d\n", svm->pasid); ret = -ENOSPC; goto out; } /* Find the matching device in svm list */ for_each_svm_dev(sdev, svm, dev) { if (sdev->ops != ops) { ret = -EBUSY; goto out; } sdev->users++; goto success; } break; } } sdev = kzalloc(sizeof(*sdev), GFP_KERNEL); if (!sdev) { ret = -ENOMEM; goto out; } sdev->dev = dev; sdev->iommu = iommu; ret = intel_iommu_enable_pasid(iommu, dev); if (ret) { kfree(sdev); goto out; } info = get_domain_info(dev); sdev->did = FLPT_DEFAULT_DID; sdev->sid = PCI_DEVID(info->bus, info->devfn); if (info->ats_enabled) { sdev->dev_iotlb = 1; sdev->qdep = info->ats_qdep; if (sdev->qdep >= QI_DEV_EIOTLB_MAX_INVS) sdev->qdep = 0; } /* Finish the setup now we know we're keeping it */ sdev->users = 1; sdev->ops = ops; init_rcu_head(&sdev->rcu); if (!svm) { svm = kzalloc(sizeof(*svm), GFP_KERNEL); if (!svm) { ret = -ENOMEM; kfree(sdev); goto out; } if (pasid_max > intel_pasid_max_id) pasid_max = intel_pasid_max_id; /* Do not use PASID 0, reserved for RID to PASID */ svm->pasid = ioasid_alloc(NULL, PASID_MIN, pasid_max - 1, svm); if (svm->pasid == INVALID_IOASID) { kfree(svm); kfree(sdev); ret = -ENOSPC; goto out; } svm->notifier.ops = &intel_mmuops; svm->mm = mm; svm->flags = flags; INIT_LIST_HEAD_RCU(&svm->devs); INIT_LIST_HEAD(&svm->list); ret = -ENOMEM; if (mm) { ret = mmu_notifier_register(&svm->notifier, mm); if (ret) { ioasid_free(svm->pasid); kfree(svm); kfree(sdev); goto out; } } spin_lock_irqsave(&iommu->lock, iflags); ret = intel_pasid_setup_first_level(iommu, dev, mm ? mm->pgd : init_mm.pgd, svm->pasid, FLPT_DEFAULT_DID, (mm ? 0 : PASID_FLAG_SUPERVISOR_MODE) | (cpu_feature_enabled(X86_FEATURE_LA57) ? PASID_FLAG_FL5LP : 0)); spin_unlock_irqrestore(&iommu->lock, iflags); if (ret) { if (mm) mmu_notifier_unregister(&svm->notifier, mm); ioasid_free(svm->pasid); kfree(svm); kfree(sdev); goto out; } list_add_tail(&svm->list, &global_svm_list); if (mm) { /* The newly allocated pasid is loaded to the mm. */ load_pasid(mm, svm->pasid); } } else { /* * Binding a new device with existing PASID, need to setup * the PASID entry. */ spin_lock_irqsave(&iommu->lock, iflags); ret = intel_pasid_setup_first_level(iommu, dev, mm ? mm->pgd : init_mm.pgd, svm->pasid, FLPT_DEFAULT_DID, (mm ? 0 : PASID_FLAG_SUPERVISOR_MODE) | (cpu_feature_enabled(X86_FEATURE_LA57) ? PASID_FLAG_FL5LP : 0)); spin_unlock_irqrestore(&iommu->lock, iflags); if (ret) { kfree(sdev); goto out; } } list_add_rcu(&sdev->list, &svm->devs); success: sdev->pasid = svm->pasid; sdev->sva.dev = dev; if (sd) *sd = sdev; ret = 0; out: return ret; } /* Caller must hold pasid_mutex */ static int intel_svm_unbind_mm(struct device *dev, u32 pasid) { struct intel_svm_dev *sdev; struct intel_iommu *iommu; struct intel_svm *svm; int ret = -EINVAL; iommu = device_to_iommu(dev, NULL, NULL); if (!iommu) goto out; ret = pasid_to_svm_sdev(dev, pasid, &svm, &sdev); if (ret) goto out; if (sdev) { sdev->users--; if (!sdev->users) { list_del_rcu(&sdev->list); /* Flush the PASID cache and IOTLB for this device. * Note that we do depend on the hardware *not* using * the PASID any more. Just as we depend on other * devices never using PASIDs that they have no right * to use. We have a *shared* PASID table, because it's * large and has to be physically contiguous. So it's * hard to be as defensive as we might like. */ intel_pasid_tear_down_entry(iommu, dev, svm->pasid, false); intel_svm_drain_prq(dev, svm->pasid); kfree_rcu(sdev, rcu); if (list_empty(&svm->devs)) { ioasid_free(svm->pasid); if (svm->mm) { mmu_notifier_unregister(&svm->notifier, svm->mm); /* Clear mm's pasid. */ load_pasid(svm->mm, PASID_DISABLED); } list_del(&svm->list); /* We mandate that no page faults may be outstanding * for the PASID when intel_svm_unbind_mm() is called. * If that is not obeyed, subtle errors will happen. * Let's make them less subtle... */ memset(svm, 0x6b, sizeof(*svm)); kfree(svm); } } } out: return ret; } /* Page request queue descriptor */ struct page_req_dsc { union { struct { u64 type:8; u64 pasid_present:1; u64 priv_data_present:1; u64 rsvd:6; u64 rid:16; u64 pasid:20; u64 exe_req:1; u64 pm_req:1; u64 rsvd2:10; }; u64 qw_0; }; union { struct { u64 rd_req:1; u64 wr_req:1; u64 lpig:1; u64 prg_index:9; u64 addr:52; }; u64 qw_1; }; u64 priv_data[2]; }; #define PRQ_RING_MASK ((0x1000 << PRQ_ORDER) - 0x20) static bool access_error(struct vm_area_struct *vma, struct page_req_dsc *req) { unsigned long requested = 0; if (req->exe_req) requested |= VM_EXEC; if (req->rd_req) requested |= VM_READ; if (req->wr_req) requested |= VM_WRITE; return (requested & ~vma->vm_flags) != 0; } static bool is_canonical_address(u64 addr) { int shift = 64 - (__VIRTUAL_MASK_SHIFT + 1); long saddr = (long) addr; return (((saddr << shift) >> shift) == saddr); } /** * intel_svm_drain_prq - Drain page requests and responses for a pasid * @dev: target device * @pasid: pasid for draining * * Drain all pending page requests and responses related to @pasid in both * software and hardware. This is supposed to be called after the device * driver has stopped DMA, the pasid entry has been cleared, and both IOTLB * and DevTLB have been invalidated. * * It waits until all pending page requests for @pasid in the page fault * queue are completed by the prq handling thread. Then follow the steps * described in VT-d spec CH7.10 to drain all page requests and page * responses pending in the hardware. */ static void intel_svm_drain_prq(struct device *dev, u32 pasid) { struct device_domain_info *info; struct dmar_domain *domain; struct intel_iommu *iommu; struct qi_desc desc[3]; struct pci_dev *pdev; int head, tail; u16 sid, did; int qdep; info = get_domain_info(dev); if (WARN_ON(!info || !dev_is_pci(dev))) return; if (!info->pri_enabled) return; iommu = info->iommu; domain = info->domain; pdev = to_pci_dev(dev); sid = PCI_DEVID(info->bus, info->devfn); did = domain->iommu_did[iommu->seq_id]; qdep = pci_ats_queue_depth(pdev); /* * Check and wait until all pending page requests in the queue are * handled by the prq handling thread. */ prq_retry: reinit_completion(&iommu->prq_complete); 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 page_req_dsc *req; req = &iommu->prq[head / sizeof(*req)]; if (!req->pasid_present || req->pasid != pasid) { head = (head + sizeof(*req)) & PRQ_RING_MASK; continue; } wait_for_completion(&iommu->prq_complete); goto prq_retry; } /* * Perform steps described in VT-d spec CH7.10 to drain page * requests and responses in hardware. */ memset(desc, 0, sizeof(desc)); desc[0].qw0 = QI_IWD_STATUS_DATA(QI_DONE) | QI_IWD_FENCE | QI_IWD_TYPE; desc[1].qw0 = QI_EIOTLB_PASID(pasid) | QI_EIOTLB_DID(did) | QI_EIOTLB_GRAN(QI_GRAN_NONG_PASID) | QI_EIOTLB_TYPE; desc[2].qw0 = QI_DEV_EIOTLB_PASID(pasid) | QI_DEV_EIOTLB_SID(sid) | QI_DEV_EIOTLB_QDEP(qdep) | QI_DEIOTLB_TYPE | QI_DEV_IOTLB_PFSID(info->pfsid); qi_retry: reinit_completion(&iommu->prq_complete); qi_submit_sync(iommu, desc, 3, QI_OPT_WAIT_DRAIN); if (readl(iommu->reg + DMAR_PRS_REG) & DMA_PRS_PRO) { wait_for_completion(&iommu->prq_complete); goto qi_retry; } } 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; if (!dev || !dev_is_pci(dev)) return -ENODEV; /* Fill in event data for device specific processing */ memset(&event, 0, sizeof(struct iommu_fault_event)); event.fault.type = IOMMU_FAULT_PAGE_REQ; event.fault.prm.addr = (u64)desc->addr << VTD_PAGE_SHIFT; event.fault.prm.pasid = desc->pasid; event.fault.prm.grpid = desc->prg_index; event.fault.prm.perm = prq_to_iommu_prot(desc); 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; event.fault.prm.flags |= IOMMU_FAULT_PAGE_RESPONSE_NEEDS_PASID; } if (desc->priv_data_present) { /* * Set last page in group bit if private data is present, * page response is required as it does for LPIG. * iommu_report_device_fault() doesn't understand this vendor * specific requirement thus we set last_page as a workaround. */ 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_svm_dev *sdev = NULL; struct intel_iommu *iommu = d; struct intel_svm *svm = NULL; int head, tail, handled = 0; /* Clear PPR bit before reading head/tail registers, to * ensure that we get a new interrupt if needed. */ writel(DMA_PRS_PPR, iommu->reg + DMAR_PRS_REG); 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 vm_area_struct *vma; struct page_req_dsc *req; struct qi_desc resp; int result; vm_fault_t ret; u64 address; handled = 1; req = &iommu->prq[head / sizeof(*req)]; result = QI_RESP_FAILURE; address = (u64)req->addr << VTD_PAGE_SHIFT; if (!req->pasid_present) { pr_err("%s: Page request without PASID: %08llx %08llx\n", iommu->name, ((unsigned long long *)req)[0], ((unsigned long long *)req)[1]); goto no_pasid; } /* We shall not receive page request for supervisor SVM */ if (req->pm_req && (req->rd_req | req->wr_req)) { pr_err("Unexpected page request in Privilege Mode"); /* No need to find the matching sdev as for bad_req */ goto no_pasid; } /* DMA read with exec requeset is not supported. */ if (req->exe_req && req->rd_req) { pr_err("Execution request not supported\n"); goto no_pasid; } if (!svm || svm->pasid != req->pasid) { rcu_read_lock(); svm = ioasid_find(NULL, req->pasid, NULL); /* It *can't* go away, because the driver is not permitted * to unbind the mm while any page faults are outstanding. * So we only need RCU to protect the internal idr code. */ rcu_read_unlock(); if (IS_ERR_OR_NULL(svm)) { pr_err("%s: Page request for invalid PASID %d: %08llx %08llx\n", iommu->name, req->pasid, ((unsigned long long *)req)[0], ((unsigned long long *)req)[1]); goto no_pasid; } } 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. */ if (!svm->mm) goto bad_req; /* If address is not canonical, return invalid response */ 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; mmap_read_lock(svm->mm); vma = find_extend_vma(svm->mm, address); if (!vma || address < vma->vm_start) goto invalid; if (access_error(vma, req)) goto invalid; ret = handle_mm_fault(vma, address, req->wr_req ? FAULT_FLAG_WRITE : 0, NULL); if (ret & VM_FAULT_ERROR) goto invalid; result = QI_RESP_SUCCESS; invalid: mmap_read_unlock(svm->mm); mmput(svm->mm); bad_req: WARN_ON(!sdev); 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); sdev->ops->fault_cb(sdev->dev, req->pasid, req->addr, req->priv_data, rwxp, result); } /* We get here in the error case where the PASID lookup failed, and these can be NULL. Do not use them below this point! */ sdev = NULL; svm = NULL; no_pasid: if (req->lpig || req->priv_data_present) { /* * Per VT-d spec. v3.0 ch7.7, system software must * respond with page group response if private data * is present (PDP) or last page in group (LPIG) bit * is set. This is an additional VT-d feature beyond * PCI ATS spec. */ resp.qw0 = QI_PGRP_PASID(req->pasid) | QI_PGRP_DID(req->rid) | QI_PGRP_PASID_P(req->pasid_present) | QI_PGRP_PDP(req->priv_data_present) | QI_PGRP_RESP_CODE(result) | QI_PGRP_RESP_TYPE; resp.qw1 = QI_PGRP_IDX(req->prg_index) | QI_PGRP_LPIG(req->lpig); resp.qw2 = 0; resp.qw3 = 0; if (req->priv_data_present) memcpy(&resp.qw2, req->priv_data, sizeof(req->priv_data)); qi_submit_sync(iommu, &resp, 1, 0); } prq_advance: head = (head + sizeof(*req)) & PRQ_RING_MASK; } dmar_writeq(iommu->reg + DMAR_PQH_REG, tail); /* * Clear the page request overflow bit and wake up all threads that * are waiting for the completion of this handling. */ if (readl(iommu->reg + DMAR_PRS_REG) & DMA_PRS_PRO) { pr_info_ratelimited("IOMMU: %s: PRQ overflow detected\n", iommu->name); head = dmar_readq(iommu->reg + DMAR_PQH_REG) & PRQ_RING_MASK; tail = dmar_readq(iommu->reg + DMAR_PQT_REG) & PRQ_RING_MASK; if (head == tail) { writel(DMA_PRS_PRO, iommu->reg + DMAR_PRS_REG); pr_info_ratelimited("IOMMU: %s: PRQ overflow cleared", iommu->name); } } if (!completion_done(&iommu->prq_complete)) complete(&iommu->prq_complete); return IRQ_RETVAL(handled); } #define to_intel_svm_dev(handle) container_of(handle, struct intel_svm_dev, sva) struct iommu_sva * intel_svm_bind(struct device *dev, struct mm_struct *mm, void *drvdata) { struct iommu_sva *sva = ERR_PTR(-EINVAL); struct intel_svm_dev *sdev = NULL; unsigned int flags = 0; int ret; /* * TODO: Consolidate with generic iommu-sva bind after it is merged. * It will require shared SVM data structures, i.e. combine io_mm * and intel_svm etc. */ if (drvdata) flags = *(unsigned int *)drvdata; mutex_lock(&pasid_mutex); ret = intel_svm_bind_mm(dev, flags, NULL, mm, &sdev); if (ret) sva = ERR_PTR(ret); else if (sdev) sva = &sdev->sva; else WARN(!sdev, "SVM bind succeeded with no sdev!\n"); mutex_unlock(&pasid_mutex); return sva; } void intel_svm_unbind(struct iommu_sva *sva) { struct intel_svm_dev *sdev; mutex_lock(&pasid_mutex); sdev = to_intel_svm_dev(sva); intel_svm_unbind_mm(sdev->dev, sdev->pasid); mutex_unlock(&pasid_mutex); } u32 intel_svm_get_pasid(struct iommu_sva *sva) { struct intel_svm_dev *sdev; u32 pasid; mutex_lock(&pasid_mutex); sdev = to_intel_svm_dev(sva); pasid = sdev->pasid; mutex_unlock(&pasid_mutex); return pasid; } int intel_svm_page_response(struct device *dev, struct iommu_fault_event *evt, struct iommu_page_response *msg) { struct iommu_fault_page_request *prm; struct intel_svm_dev *sdev = NULL; struct intel_svm *svm = NULL; struct intel_iommu *iommu; bool private_present; bool pasid_present; bool last_page; u8 bus, devfn; int ret = 0; u16 sid; if (!dev || !dev_is_pci(dev)) return -ENODEV; iommu = device_to_iommu(dev, &bus, &devfn); if (!iommu) return -ENODEV; if (!msg || !evt) return -EINVAL; mutex_lock(&pasid_mutex); prm = &evt->fault.prm; sid = PCI_DEVID(bus, devfn); pasid_present = prm->flags & IOMMU_FAULT_PAGE_REQUEST_PASID_VALID; private_present = prm->flags & IOMMU_FAULT_PAGE_REQUEST_PRIV_DATA; last_page = prm->flags & IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE; if (!pasid_present) { ret = -EINVAL; goto out; } if (prm->pasid == 0 || prm->pasid >= PASID_MAX) { ret = -EINVAL; goto out; } ret = pasid_to_svm_sdev(dev, prm->pasid, &svm, &sdev); if (ret || !sdev) { ret = -ENODEV; goto out; } /* * For responses from userspace, need to make sure that the * pasid has been bound to its mm. */ if (svm->flags & SVM_FLAG_GUEST_MODE) { struct mm_struct *mm; mm = get_task_mm(current); if (!mm) { ret = -EINVAL; goto out; } if (mm != svm->mm) { ret = -ENODEV; mmput(mm); goto out; } mmput(mm); } /* * Per VT-d spec. v3.0 ch7.7, system software must respond * with page group response if private data is present (PDP) * or last page in group (LPIG) bit is set. This is an * additional VT-d requirement beyond PCI ATS spec. */ if (last_page || private_present) { struct qi_desc desc; desc.qw0 = QI_PGRP_PASID(prm->pasid) | QI_PGRP_DID(sid) | QI_PGRP_PASID_P(pasid_present) | QI_PGRP_PDP(private_present) | QI_PGRP_RESP_CODE(msg->code) | QI_PGRP_RESP_TYPE; desc.qw1 = QI_PGRP_IDX(prm->grpid) | QI_PGRP_LPIG(last_page); desc.qw2 = 0; desc.qw3 = 0; if (private_present) memcpy(&desc.qw2, prm->private_data, sizeof(prm->private_data)); qi_submit_sync(iommu, &desc, 1, 0); } out: mutex_unlock(&pasid_mutex); return ret; }