[PATCH v2 3/8] iommu/vt-d: Implement second level page table ops

Lu Baolu
2019-11-28T02:30:07Z

This adds the implementation of page table callbacks for
the second level page table.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Liu Yi L <yi.l.liu@intel.com>
Cc: Yi Sun <yi.y.sun@linux.intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
drivers/iommu/intel-iommu.c | 81 +++++++++++++++++++++++++++++++++++++
1 file changed, 81 insertions(+)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 7752ff299cb5..96ead4e3395a 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -413,6 +413,7 @@ int for_each_device_domain(int (*fn)(struct device_domain_info *info,
}

const struct iommu_ops intel_iommu_ops;
+static const struct pgtable_ops second_lvl_pgtable_ops;

static bool translation_pre_enabled(struct intel_iommu *iommu)
{
@@ -1720,6 +1721,7 @@ static struct dmar_domain *alloc_domain(int flags)
domain->nid = NUMA_NO_NODE;
domain->flags = flags;
domain->has_iotlb_device = false;
+ domain->ops = &second_lvl_pgtable_ops;
INIT_LIST_HEAD(&domain->devices);

return domain;
@@ -2334,6 +2336,85 @@ static int __domain_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
return 0;
}

+static int second_lvl_domain_map_range(struct dmar_domain *domain,
+ unsigned long iova, phys_addr_t paddr,
+ size_t size, int prot)
+{
+ return __domain_mapping(domain, iova >> VTD_PAGE_SHIFT, NULL,
+ paddr >> VTD_PAGE_SHIFT,
+ aligned_nrpages(paddr, size), prot);
+}
+
+static struct page *
+second_lvl_domain_unmap_range(struct dmar_domain *domain,
+ unsigned long iova, size_t size)
+{
+ unsigned long start_pfn, end_pfn, nrpages;
+
+ start_pfn = mm_to_dma_pfn(IOVA_PFN(iova));
+ nrpages = aligned_nrpages(iova, size);
+ end_pfn = start_pfn + nrpages - 1;
+
+ return dma_pte_clear_level(domain, agaw_to_level(domain->agaw),
+ domain->pgd, 0, start_pfn, end_pfn, NULL);
+}
+
+static phys_addr_t
+second_lvl_domain_iova_to_phys(struct dmar_domain *domain,
+ unsigned long iova)
+{
+ struct dma_pte *pte;
+ int level = 0;
+ u64 phys = 0;
+
+ pte = pfn_to_dma_pte(domain, iova >> VTD_PAGE_SHIFT, &level);
+ if (pte)
+ phys = dma_pte_addr(pte);
+
+ return phys;
+}
+
+static void
+second_lvl_domain_flush_tlb_range(struct dmar_domain *domain,
+ struct intel_iommu *iommu,
+ unsigned long addr, size_t size,
+ bool ih)
+{
+ unsigned long pages = aligned_nrpages(addr, size);
+ u16 did = domain->iommu_did[iommu->seq_id];
+ unsigned int mask;
+
+ if (pages) {
+ mask = ilog2(__roundup_pow_of_two(pages));
+ addr &= (u64)-1 << (VTD_PAGE_SHIFT + mask);
+ } else {
+ mask = MAX_AGAW_PFN_WIDTH;
+ addr = 0;
+ }
+
+ /*
+ * Fallback to domain selective flush if no PSI support or the size is
+ * too big.
+ * PSI requires page size to be 2 ^ x, and the base address is naturally
+ * aligned to the size
+ */
+ if (!pages || !cap_pgsel_inv(iommu->cap) ||
+ mask > cap_max_amask_val(iommu->cap))
+ iommu->flush.iotlb_inv(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH);
+ else
+ iommu->flush.iotlb_inv(iommu, did, addr | ((int)ih << 6),
+ mask, DMA_TLB_PSI_FLUSH);
+
+ iommu_flush_dev_iotlb(domain, addr, mask);
+}
+
+static const struct pgtable_ops second_lvl_pgtable_ops = {
+ .map_range = second_lvl_domain_map_range,
+ .unmap_range = second_lvl_domain_unmap_range,
+ .iova_to_phys = second_lvl_domain_iova_to_phys,
+ .flush_tlb_range = second_lvl_domain_flush_tlb_range,
+};
+
static int domain_mapping(struct dmar_domain *domain, unsigned long iov_pfn,
struct scatterlist *sg, unsigned long phys_pfn,
unsigned long nr_pages, int prot)
--
2.17.1