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-rw-r--r--drivers/iommu/intel/svm.c850
1 files changed, 850 insertions, 0 deletions
diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
new file mode 100644
index 000000000..ac12f76c1
--- /dev/null
+++ b/drivers/iommu/intel/svm.c
@@ -0,0 +1,850 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright © 2015 Intel Corporation.
+ *
+ * Authors: David Woodhouse <dwmw2@infradead.org>
+ */
+
+#include <linux/mmu_notifier.h>
+#include <linux/sched.h>
+#include <linux/sched/mm.h>
+#include <linux/slab.h>
+#include <linux/rculist.h>
+#include <linux/pci.h>
+#include <linux/pci-ats.h>
+#include <linux/dmar.h>
+#include <linux/interrupt.h>
+#include <linux/mm_types.h>
+#include <linux/xarray.h>
+#include <asm/page.h>
+#include <asm/fpu/api.h>
+
+#include "iommu.h"
+#include "pasid.h"
+#include "perf.h"
+#include "../iommu-sva.h"
+#include "trace.h"
+
+static irqreturn_t prq_event_thread(int irq, void *d);
+
+static DEFINE_XARRAY_ALLOC(pasid_private_array);
+static int pasid_private_add(ioasid_t pasid, void *priv)
+{
+ return xa_alloc(&pasid_private_array, &pasid, priv,
+ XA_LIMIT(pasid, pasid), GFP_ATOMIC);
+}
+
+static void pasid_private_remove(ioasid_t pasid)
+{
+ xa_erase(&pasid_private_array, pasid);
+}
+
+static void *pasid_private_find(ioasid_t pasid)
+{
+ return xa_load(&pasid_private_array, pasid);
+}
+
+static struct intel_svm_dev *
+svm_lookup_device_by_dev(struct intel_svm *svm, struct device *dev)
+{
+ struct intel_svm_dev *sdev = NULL, *t;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(t, &svm->devs, list) {
+ if (t->dev == dev) {
+ sdev = t;
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+ return sdev;
+}
+
+int intel_svm_enable_prq(struct intel_iommu *iommu)
+{
+ struct iopf_queue *iopfq;
+ 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(IOMMU_IRQ_ID_OFFSET_PRQ + 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;
+ goto free_prq;
+ }
+ iommu->pr_irq = irq;
+
+ snprintf(iommu->iopfq_name, sizeof(iommu->iopfq_name),
+ "dmar%d-iopfq", iommu->seq_id);
+ iopfq = iopf_queue_alloc(iommu->iopfq_name);
+ if (!iopfq) {
+ pr_err("IOMMU: %s: Failed to allocate iopf queue\n", iommu->name);
+ ret = -ENOMEM;
+ goto free_hwirq;
+ }
+ iommu->iopf_queue = iopfq;
+
+ 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);
+ goto free_iopfq;
+ }
+ 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;
+
+free_iopfq:
+ iopf_queue_free(iommu->iopf_queue);
+ iommu->iopf_queue = NULL;
+free_hwirq:
+ dmar_free_hwirq(irq);
+ iommu->pr_irq = 0;
+free_prq:
+ free_pages((unsigned long)iommu->prq, PRQ_ORDER);
+ iommu->prq = NULL;
+
+ return ret;
+}
+
+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;
+ }
+
+ if (iommu->iopf_queue) {
+ iopf_queue_free(iommu->iopf_queue);
+ iommu->iopf_queue = NULL;
+ }
+
+ free_pages((unsigned long)iommu->prq, PRQ_ORDER);
+ iommu->prq = NULL;
+
+ return 0;
+}
+
+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_fl5lp_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 = dev_iommu_priv_get(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));
+ quirk_extra_dev_tlb_flush(info, address, order_base_2(pages),
+ svm->pasid, sdev->qdep);
+ }
+}
+
+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();
+}
+
+static void intel_flush_svm_all(struct intel_svm *svm)
+{
+ struct device_domain_info *info;
+ struct intel_svm_dev *sdev;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(sdev, &svm->devs, list) {
+ info = dev_iommu_priv_get(sdev->dev);
+
+ qi_flush_piotlb(sdev->iommu, sdev->did, svm->pasid, 0, -1UL, 0);
+ if (info->ats_enabled) {
+ qi_flush_dev_iotlb_pasid(sdev->iommu, sdev->sid, info->pfsid,
+ svm->pasid, sdev->qdep,
+ 0, 64 - VTD_PAGE_SHIFT);
+ quirk_extra_dev_tlb_flush(info, 0, 64 - VTD_PAGE_SHIFT,
+ svm->pasid, sdev->qdep);
+ }
+ }
+ rcu_read_unlock();
+}
+
+/* Pages have been freed at this point */
+static void intel_arch_invalidate_secondary_tlbs(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);
+
+ if (start == 0 && end == -1UL) {
+ intel_flush_svm_all(svm);
+ return;
+ }
+
+ 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,
+ .arch_invalidate_secondary_tlbs = intel_arch_invalidate_secondary_tlbs,
+};
+
+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 *sdev = NULL;
+ struct intel_svm *svm;
+
+ if (pasid == IOMMU_PASID_INVALID || pasid >= PASID_MAX)
+ return -EINVAL;
+
+ svm = pasid_private_find(pasid);
+ 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;
+ sdev = svm_lookup_device_by_dev(svm, dev);
+
+out:
+ *rsvm = svm;
+ *rsdev = sdev;
+
+ return 0;
+}
+
+static int intel_svm_bind_mm(struct intel_iommu *iommu, struct device *dev,
+ struct mm_struct *mm)
+{
+ struct device_domain_info *info = dev_iommu_priv_get(dev);
+ struct intel_svm_dev *sdev;
+ struct intel_svm *svm;
+ unsigned long sflags;
+ int ret = 0;
+
+ svm = pasid_private_find(mm->pasid);
+ if (!svm) {
+ svm = kzalloc(sizeof(*svm), GFP_KERNEL);
+ if (!svm)
+ return -ENOMEM;
+
+ svm->pasid = mm->pasid;
+ svm->mm = mm;
+ INIT_LIST_HEAD_RCU(&svm->devs);
+
+ svm->notifier.ops = &intel_mmuops;
+ ret = mmu_notifier_register(&svm->notifier, mm);
+ if (ret) {
+ kfree(svm);
+ return ret;
+ }
+
+ ret = pasid_private_add(svm->pasid, svm);
+ if (ret) {
+ mmu_notifier_unregister(&svm->notifier, mm);
+ kfree(svm);
+ return ret;
+ }
+ }
+
+ sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
+ if (!sdev) {
+ ret = -ENOMEM;
+ goto free_svm;
+ }
+
+ sdev->dev = dev;
+ sdev->iommu = iommu;
+ sdev->did = FLPT_DEFAULT_DID;
+ sdev->sid = PCI_DEVID(info->bus, info->devfn);
+ init_rcu_head(&sdev->rcu);
+ if (info->ats_enabled) {
+ sdev->qdep = info->ats_qdep;
+ if (sdev->qdep >= QI_DEV_EIOTLB_MAX_INVS)
+ sdev->qdep = 0;
+ }
+
+ /* Setup the pasid table: */
+ sflags = cpu_feature_enabled(X86_FEATURE_LA57) ? PASID_FLAG_FL5LP : 0;
+ ret = intel_pasid_setup_first_level(iommu, dev, mm->pgd, mm->pasid,
+ FLPT_DEFAULT_DID, sflags);
+ if (ret)
+ goto free_sdev;
+
+ list_add_rcu(&sdev->list, &svm->devs);
+
+ return 0;
+
+free_sdev:
+ kfree(sdev);
+free_svm:
+ if (list_empty(&svm->devs)) {
+ mmu_notifier_unregister(&svm->notifier, mm);
+ pasid_private_remove(mm->pasid);
+ kfree(svm);
+ }
+
+ return ret;
+}
+
+void intel_svm_remove_dev_pasid(struct device *dev, u32 pasid)
+{
+ struct intel_svm_dev *sdev;
+ struct intel_iommu *iommu;
+ struct intel_svm *svm;
+ struct mm_struct *mm;
+
+ iommu = device_to_iommu(dev, NULL, NULL);
+ if (!iommu)
+ return;
+
+ if (pasid_to_svm_sdev(dev, pasid, &svm, &sdev))
+ return;
+ mm = svm->mm;
+
+ if (sdev) {
+ list_del_rcu(&sdev->list);
+ kfree_rcu(sdev, rcu);
+
+ if (list_empty(&svm->devs)) {
+ if (svm->notifier.ops)
+ mmu_notifier_unregister(&svm->notifier, mm);
+ pasid_private_remove(svm->pasid);
+ /*
+ * 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);
+ }
+ }
+}
+
+/* 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];
+};
+
+static bool is_canonical_address(u64 addr)
+{
+ int shift = 64 - (__VIRTUAL_MASK_SHIFT + 1);
+ long saddr = (long) addr;
+
+ return (((saddr << shift) >> shift) == saddr);
+}
+
+/**
+ * intel_drain_pasid_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.
+ */
+void intel_drain_pasid_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 = dev_iommu_priv_get(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_id_iommu(domain, iommu);
+ 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;
+ }
+
+ iopf_queue_flush_dev(dev);
+
+ /*
+ * 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 intel_iommu *iommu, 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;
+ event.fault.prm.private_data[0] = desc->priv_data[0];
+ event.fault.prm.private_data[1] = desc->priv_data[1];
+ } else if (dmar_latency_enabled(iommu, DMAR_LATENCY_PRQ)) {
+ /*
+ * If the private data fields are not used by hardware, use it
+ * to monitor the prq handle latency.
+ */
+ event.fault.prm.private_data[0] = ktime_to_ns(ktime_get());
+ }
+
+ return iommu_report_device_fault(dev, &event);
+}
+
+static void handle_bad_prq_event(struct intel_iommu *iommu,
+ struct page_req_dsc *req, int result)
+{
+ struct qi_desc desc;
+
+ pr_err("%s: Invalid page request: %08llx %08llx\n",
+ iommu->name, ((unsigned long long *)req)[0],
+ ((unsigned long long *)req)[1]);
+
+ /*
+ * 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.
+ */
+ if (!req->lpig && !req->priv_data_present)
+ return;
+
+ desc.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;
+ desc.qw1 = QI_PGRP_IDX(req->prg_index) |
+ QI_PGRP_LPIG(req->lpig);
+
+ if (req->priv_data_present) {
+ desc.qw2 = req->priv_data[0];
+ desc.qw3 = req->priv_data[1];
+ } else {
+ desc.qw2 = 0;
+ desc.qw3 = 0;
+ }
+
+ qi_submit_sync(iommu, &desc, 1, 0);
+}
+
+static irqreturn_t prq_event_thread(int irq, void *d)
+{
+ struct intel_iommu *iommu = d;
+ struct page_req_dsc *req;
+ int head, tail, handled;
+ struct pci_dev *pdev;
+ u64 address;
+
+ /*
+ * 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;
+ handled = (head != tail);
+ while (head != tail) {
+ req = &iommu->prq[head / sizeof(*req)];
+ address = (u64)req->addr << VTD_PAGE_SHIFT;
+
+ if (unlikely(!req->pasid_present)) {
+ pr_err("IOMMU: %s: Page request without PASID\n",
+ iommu->name);
+bad_req:
+ handle_bad_prq_event(iommu, req, QI_RESP_INVALID);
+ goto prq_advance;
+ }
+
+ if (unlikely(!is_canonical_address(address))) {
+ pr_err("IOMMU: %s: Address is not canonical\n",
+ iommu->name);
+ goto bad_req;
+ }
+
+ if (unlikely(req->pm_req && (req->rd_req | req->wr_req))) {
+ pr_err("IOMMU: %s: Page request in Privilege Mode\n",
+ iommu->name);
+ goto bad_req;
+ }
+
+ if (unlikely(req->exe_req && req->rd_req)) {
+ pr_err("IOMMU: %s: Execution request not supported\n",
+ iommu->name);
+ goto bad_req;
+ }
+
+ /* Drop Stop Marker message. No need for a response. */
+ if (unlikely(req->lpig && !req->rd_req && !req->wr_req))
+ goto prq_advance;
+
+ pdev = pci_get_domain_bus_and_slot(iommu->segment,
+ PCI_BUS_NUM(req->rid),
+ req->rid & 0xff);
+ /*
+ * If prq is to be handled outside iommu driver via receiver of
+ * the fault notifiers, we skip the page response here.
+ */
+ if (!pdev)
+ goto bad_req;
+
+ if (intel_svm_prq_report(iommu, &pdev->dev, req))
+ handle_bad_prq_event(iommu, req, QI_RESP_INVALID);
+ else
+ trace_prq_report(iommu, &pdev->dev, req->qw_0, req->qw_1,
+ req->priv_data[0], req->priv_data[1],
+ iommu->prq_seq_number++);
+ pci_dev_put(pdev);
+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) {
+ iopf_queue_discard_partial(iommu->iopf_queue);
+ 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);
+}
+
+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_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;
+
+ 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;
+ }
+
+ /*
+ * 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) {
+ desc.qw2 = prm->private_data[0];
+ desc.qw3 = prm->private_data[1];
+ } else if (prm->private_data[0]) {
+ dmar_latency_update(iommu, DMAR_LATENCY_PRQ,
+ ktime_to_ns(ktime_get()) - prm->private_data[0]);
+ }
+
+ qi_submit_sync(iommu, &desc, 1, 0);
+ }
+out:
+ return ret;
+}
+
+static int intel_svm_set_dev_pasid(struct iommu_domain *domain,
+ struct device *dev, ioasid_t pasid)
+{
+ struct device_domain_info *info = dev_iommu_priv_get(dev);
+ struct intel_iommu *iommu = info->iommu;
+ struct mm_struct *mm = domain->mm;
+
+ return intel_svm_bind_mm(iommu, dev, mm);
+}
+
+static void intel_svm_domain_free(struct iommu_domain *domain)
+{
+ kfree(to_dmar_domain(domain));
+}
+
+static const struct iommu_domain_ops intel_svm_domain_ops = {
+ .set_dev_pasid = intel_svm_set_dev_pasid,
+ .free = intel_svm_domain_free
+};
+
+struct iommu_domain *intel_svm_domain_alloc(void)
+{
+ struct dmar_domain *domain;
+
+ domain = kzalloc(sizeof(*domain), GFP_KERNEL);
+ if (!domain)
+ return NULL;
+ domain->domain.ops = &intel_svm_domain_ops;
+
+ return &domain->domain;
+}