Messages in this thread |  | | From | "Tian, Kevin" <> | Subject | RE: [PATCH 2/9] iommu/vt-d: add bind_pasid_table function | Date | Wed, 5 Jul 2017 07:38:07 +0000 |
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> From: Jacob Pan [mailto:jacob.jun.pan@linux.intel.com] > Sent: Wednesday, June 28, 2017 3:48 AM > > Add Intel VT-d ops to the generic iommu_bind_pasid_table API > functions. > > The primary use case is for direct assignment of SVM capable > device. Originated from emulated IOMMU in the guest, the request goes > through many layers (e.g. VFIO). Upon calling host IOMMU driver, caller > passes guest PASID table pointer (GPA) and size. > > Device context table entry is modified by Intel IOMMU specific > bind_pasid_table function. This will turn on nesting mode and matching > translation type. > > The unbind operation restores default context mapping. > > Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> > Signed-off-by: Liu, Yi L <yi.l.liu@linux.intel.com> > Signed-off-by: Ashok Raj <ashok.raj@intel.com> > --- > drivers/iommu/intel-iommu.c | 117 > ++++++++++++++++++++++++++++++++++++++++++ > include/linux/dma_remapping.h | 1 + > 2 files changed, 118 insertions(+) > > diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c > index 8274ce3..ef05b59 100644 > --- a/drivers/iommu/intel-iommu.c > +++ b/drivers/iommu/intel-iommu.c > @@ -5430,6 +5430,119 @@ struct intel_iommu > *intel_svm_device_to_iommu(struct device *dev) > > return iommu; > } > + > +static int intel_iommu_bind_pasid_table(struct iommu_domain *domain, > + struct device *dev, struct pasid_table_info *pasidt_binfo) > +{ > + struct intel_iommu *iommu; > + struct context_entry *context; > + struct dmar_domain *dmar_domain = to_dmar_domain(domain); > + struct device_domain_info *info; > + struct pci_dev *pdev; > + u8 bus, devfn; > + u16 did, *sid; > + int ret = 0; > + unsigned long flags; > + u64 ctx_lo; > + > + if (pasidt_binfo == NULL || pasidt_binfo->model != > IOMMU_MODEL_INTEL_VTD) { > + pr_warn("%s: Invalid bind request!\n", __func__); > + return -EINVAL; > + } > + > + iommu = device_to_iommu(dev, &bus, &devfn); > + if (!iommu) > + return -ENODEV; > + > + sid = (u16 *)&pasidt_binfo->opaque; > + /* > + * check SID, if it is not correct, return success to allow looping > + * through all devices within a group > + */
Can you elaborate this comment since it's related to caller behavior? Also better move to earlier as the comment for whole function...
> + if (PCI_DEVID(bus, devfn) != *sid) > + return 0; > + > + if (!dev || !dev_is_pci(dev)) > + return -ENODEV; > + > + pdev = to_pci_dev(dev); > + if (!pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI)) > + return -EINVAL; > + > + info = dev->archdata.iommu; > + if (!info || !info->pasid_supported || > + !pci_enable_pasid(pdev, info->pasid_supported & ~1)) { > + pr_err("PCI %04x:%02x:%02x.%d: has no PASID support\n", > + pci_domain_nr(pdev->bus), bus, PCI_SLOT(devfn), > + PCI_FUNC(devfn)); > + ret = -EINVAL; > + goto out; > + } > + > + if (pasidt_binfo->size > intel_iommu_get_pts(iommu)) { > + pr_err("Invalid gPASID table size %llu, host size %lu\n", > + pasidt_binfo->size, > + intel_iommu_get_pts(iommu)); > + ret = -EINVAL; > + goto out; > + } > + spin_lock_irqsave(&iommu->lock, flags); > + context = iommu_context_addr(iommu, bus, devfn, 0); > + if (!context || !context_present(context)) { > + pr_warn("%s: ctx not present for bus devfn %x:%x\n", > + __func__, bus, devfn); > + spin_unlock_irqrestore(&iommu->lock, flags); > + goto out; > + } > + > + /* Anticipate guest to use SVM and owns the first level */ > + ctx_lo = context[0].lo; > + ctx_lo |= CONTEXT_NESTE; > + ctx_lo |= CONTEXT_PRS; > + ctx_lo |= CONTEXT_PASIDE; > + ctx_lo &= ~CONTEXT_TT_MASK; > + ctx_lo |= CONTEXT_TT_DEV_IOTLB << 2; > + context[0].lo = ctx_lo; > + > + /* Assign guest PASID table pointer and size */ > + ctx_lo = (pasidt_binfo->ptr & VTD_PAGE_MASK) | pasidt_binfo->size; > + context[1].lo = ctx_lo; > + /* make sure context entry is updated before flushing */ > + wmb(); > + did = dmar_domain->iommu_did[iommu->seq_id]; > + iommu->flush.flush_context(iommu, did, > + (((u16)bus) << 8) | devfn, > + DMA_CCMD_MASK_NOBIT, > + DMA_CCMD_DEVICE_INVL); > + iommu->flush.flush_iotlb(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH); > + spin_unlock_irqrestore(&iommu->lock, flags); > + > + > +out: > + return ret; > +} > + > +static int intel_iommu_unbind_pasid_table(struct iommu_domain *domain, > + struct device *dev) > +{ > + struct intel_iommu *iommu; > + struct dmar_domain *dmar_domain = to_dmar_domain(domain); > + u8 bus, devfn; > + > + iommu = device_to_iommu(dev, &bus, &devfn); > + if (!iommu) > + return -ENODEV; > + /* > + * REVISIT: we might want to clear the PASID table pointer > + * as part of context clear operation. Currently, it leaves > + * stale data but should be ignored by hardware since PASIDE > + * is clear. > + */ > + /* ATS will be reenabled when remapping is restored */ > + pci_disable_ats(to_pci_dev(dev)); > + domain_context_clear(iommu, dev); > + return domain_context_mapping_one(dmar_domain, iommu, bus, > devfn); > +} > #endif /* CONFIG_INTEL_IOMMU_SVM */ > > const struct iommu_ops intel_iommu_ops = { > @@ -5438,6 +5551,10 @@ const struct iommu_ops intel_iommu_ops = { > .domain_free = intel_iommu_domain_free, > .attach_dev = intel_iommu_attach_device, > .detach_dev = intel_iommu_detach_device, > +#ifdef CONFIG_INTEL_IOMMU_SVM > + .bind_pasid_table = intel_iommu_bind_pasid_table, > + .unbind_pasid_table = intel_iommu_unbind_pasid_table, > +#endif > .map = intel_iommu_map, > .unmap = intel_iommu_unmap, > .map_sg = default_iommu_map_sg, > diff --git a/include/linux/dma_remapping.h > b/include/linux/dma_remapping.h > index 9088407..85367b7 100644 > --- a/include/linux/dma_remapping.h > +++ b/include/linux/dma_remapping.h > @@ -27,6 +27,7 @@ > > #define CONTEXT_DINVE (1ULL << 8) > #define CONTEXT_PRS (1ULL << 9) > +#define CONTEXT_NESTE (1ULL << 10) > #define CONTEXT_PASIDE (1ULL << 11) > > struct intel_iommu; > -- > 2.7.4
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