From e2726daea583d81e447b71e09b79e67f618d6152 Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Thu, 2 Jan 2020 08:18:22 +0800 Subject: iommu/vt-d: debugfs: Add support to show page table internals Export page table internals of the domain attached to each device. Example of such dump on a Skylake machine: $ sudo cat /sys/kernel/debug/iommu/intel/domain_translation_struct [ ... ] Device 0000:00:14.0 with pasid 0 @0x15f3d9000 IOVA_PFN PML5E PML4E 0x000000008ced0 | 0x0000000000000000 0x000000015f3da003 0x000000008ced1 | 0x0000000000000000 0x000000015f3da003 0x000000008ced2 | 0x0000000000000000 0x000000015f3da003 0x000000008ced3 | 0x0000000000000000 0x000000015f3da003 0x000000008ced4 | 0x0000000000000000 0x000000015f3da003 0x000000008ced5 | 0x0000000000000000 0x000000015f3da003 0x000000008ced6 | 0x0000000000000000 0x000000015f3da003 0x000000008ced7 | 0x0000000000000000 0x000000015f3da003 0x000000008ced8 | 0x0000000000000000 0x000000015f3da003 0x000000008ced9 | 0x0000000000000000 0x000000015f3da003 PDPE PDE PTE 0x000000015f3db003 0x000000015f3dc003 0x000000008ced0003 0x000000015f3db003 0x000000015f3dc003 0x000000008ced1003 0x000000015f3db003 0x000000015f3dc003 0x000000008ced2003 0x000000015f3db003 0x000000015f3dc003 0x000000008ced3003 0x000000015f3db003 0x000000015f3dc003 0x000000008ced4003 0x000000015f3db003 0x000000015f3dc003 0x000000008ced5003 0x000000015f3db003 0x000000015f3dc003 0x000000008ced6003 0x000000015f3db003 0x000000015f3dc003 0x000000008ced7003 0x000000015f3db003 0x000000015f3dc003 0x000000008ced8003 0x000000015f3db003 0x000000015f3dc003 0x000000008ced9003 [ ... ] Signed-off-by: Lu Baolu Signed-off-by: Joerg Roedel --- drivers/iommu/intel-iommu-debugfs.c | 75 +++++++++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) (limited to 'drivers/iommu/intel-iommu-debugfs.c') diff --git a/drivers/iommu/intel-iommu-debugfs.c b/drivers/iommu/intel-iommu-debugfs.c index 471f05d452e0..c1257bef553c 100644 --- a/drivers/iommu/intel-iommu-debugfs.c +++ b/drivers/iommu/intel-iommu-debugfs.c @@ -5,6 +5,7 @@ * Authors: Gayatri Kammela * Sohil Mehta * Jacob Pan + * Lu Baolu */ #include @@ -283,6 +284,77 @@ static int dmar_translation_struct_show(struct seq_file *m, void *unused) } DEFINE_SHOW_ATTRIBUTE(dmar_translation_struct); +static inline unsigned long level_to_directory_size(int level) +{ + return BIT_ULL(VTD_PAGE_SHIFT + VTD_STRIDE_SHIFT * (level - 1)); +} + +static inline void +dump_page_info(struct seq_file *m, unsigned long iova, u64 *path) +{ + seq_printf(m, "0x%013lx |\t0x%016llx\t0x%016llx\t0x%016llx\t0x%016llx\t0x%016llx\n", + iova >> VTD_PAGE_SHIFT, path[5], path[4], + path[3], path[2], path[1]); +} + +static void pgtable_walk_level(struct seq_file *m, struct dma_pte *pde, + int level, unsigned long start, + u64 *path) +{ + int i; + + if (level > 5 || level < 1) + return; + + for (i = 0; i < BIT_ULL(VTD_STRIDE_SHIFT); + i++, pde++, start += level_to_directory_size(level)) { + if (!dma_pte_present(pde)) + continue; + + path[level] = pde->val; + if (dma_pte_superpage(pde) || level == 1) + dump_page_info(m, start, path); + else + pgtable_walk_level(m, phys_to_virt(dma_pte_addr(pde)), + level - 1, start, path); + path[level] = 0; + } +} + +static int show_device_domain_translation(struct device *dev, void *data) +{ + struct dmar_domain *domain = find_domain(dev); + struct seq_file *m = data; + u64 path[6] = { 0 }; + + if (!domain) + return 0; + + seq_printf(m, "Device %s with pasid %d @0x%llx\n", + dev_name(dev), domain->default_pasid, + (u64)virt_to_phys(domain->pgd)); + seq_puts(m, "IOVA_PFN\t\tPML5E\t\t\tPML4E\t\t\tPDPE\t\t\tPDE\t\t\tPTE\n"); + + pgtable_walk_level(m, domain->pgd, domain->agaw + 2, 0, path); + seq_putc(m, '\n'); + + return 0; +} + +static int domain_translation_struct_show(struct seq_file *m, void *unused) +{ + unsigned long flags; + int ret; + + spin_lock_irqsave(&device_domain_lock, flags); + ret = bus_for_each_dev(&pci_bus_type, NULL, m, + show_device_domain_translation); + spin_unlock_irqrestore(&device_domain_lock, flags); + + return ret; +} +DEFINE_SHOW_ATTRIBUTE(domain_translation_struct); + #ifdef CONFIG_IRQ_REMAP static void ir_tbl_remap_entry_show(struct seq_file *m, struct intel_iommu *iommu) @@ -396,6 +468,9 @@ void __init intel_iommu_debugfs_init(void) &iommu_regset_fops); debugfs_create_file("dmar_translation_struct", 0444, intel_iommu_debug, NULL, &dmar_translation_struct_fops); + debugfs_create_file("domain_translation_struct", 0444, + intel_iommu_debug, NULL, + &domain_translation_struct_fops); #ifdef CONFIG_IRQ_REMAP debugfs_create_file("ir_translation_struct", 0444, intel_iommu_debug, NULL, &ir_translation_struct_fops); -- cgit v1.2.3-59-g8ed1b