1 files changed, 21 insertions, 19 deletions

diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index da40f0789739..57be89e6f484 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -3433,19 +3433,6 @@ static void vm_domain_remove_all_dev_info(struct dmar_domain *domain)
 /* domain id for virtual machine, it won't be set in context */
 static unsigned long vm_domid;
 
-static int vm_domain_min_agaw(struct dmar_domain *domain)
-{
-        int i;
-        int min_agaw = domain->agaw;
-
-        for_each_set_bit(i, &domain->iommu_bmp, g_num_of_iommus) {
-                if (min_agaw > g_iommus[i]->agaw)
-                        min_agaw = g_iommus[i]->agaw;
-        }
-
-        return min_agaw;
-}
-
 static struct dmar_domain *iommu_alloc_vm_domain(void)
 {
         struct dmar_domain *domain;
@@ -3574,7 +3561,6 @@ static int intel_iommu_attach_device(struct iommu_domain *domain,
         struct pci_dev *pdev = to_pci_dev(dev);
         struct intel_iommu *iommu;
         int addr_width;
-        u64 end;
 
         /* normally pdev is not mapped */
         if (unlikely(domain_context_mapped(pdev))) {
@@ -3597,14 +3583,30 @@ static int intel_iommu_attach_device(struct iommu_domain *domain,
 
         /* check if this iommu agaw is sufficient for max mapped address */
         addr_width = agaw_to_width(iommu->agaw);
-        end = DOMAIN_MAX_ADDR(addr_width);
-        end = end & VTD_PAGE_MASK;
-        if (end < dmar_domain->max_addr) {
-                printk(KERN_ERR "%s: iommu agaw (%d) is not "
+        if (addr_width > cap_mgaw(iommu->cap))
+                addr_width = cap_mgaw(iommu->cap);
+
+        if (dmar_domain->max_addr > (1LL << addr_width)) {
+                printk(KERN_ERR "%s: iommu width (%d) is not "
                        "sufficient for the mapped address (%llx)\n",
-                       __func__, iommu->agaw, dmar_domain->max_addr);
+                       __func__, addr_width, dmar_domain->max_addr);
                 return -EFAULT;
         }
+        dmar_domain->gaw = addr_width;
+
+        /*
+         * Knock out extra levels of page tables if necessary
+         */
+        while (iommu->agaw < dmar_domain->agaw) {
+                struct dma_pte *pte;
+
+                pte = dmar_domain->pgd;
+                if (dma_pte_present(pte)) {
+                        free_pgtable_page(dmar_domain->pgd);
+                        dmar_domain->pgd = (struct dma_pte *)dma_pte_addr(pte);
+                }
+                dmar_domain->agaw--;
+        }
 
         return domain_add_dev_info(dmar_domain, pdev, CONTEXT_TT_MULTI_LEVEL);
 }