[PATCH 09/13] change domain_context_mapping_one for virtual machine domain

[Han, Weidong]

vm_domid won't be set in context, find available domain id for a device from 
its iommu.

For a virtual machine domain, a default agaw will be set, and skip top levels 
of page tables for iommu which has less agaw than default.

Signed-off-by: Weidong Han <[EMAIL PROTECTED]>
---
 drivers/pci/intel-iommu.c |   57 ++++++++++++++++++++++++++++++++++++++++++--
 1 files changed, 54 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index e96b3bc..3f987d7 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -1168,6 +1168,11 @@ static int domain_context_mapping_one(struct dmar_domain 
*domain,
        struct context_entry *context;
        struct intel_iommu *iommu;
        unsigned long flags;
+       struct dma_pte *pgd;
+       unsigned long num;
+       unsigned long ndomains;
+       int id;
+       int agaw;
 
        pr_debug("Set context mapping for %02x:%02x.%d\n",
                bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
@@ -1185,9 +1190,55 @@ static int domain_context_mapping_one(struct dmar_domain 
*domain,
                return 0;
        }
 
-       context_set_domain_id(*context, domain->id);
-       context_set_address_width(*context, domain->agaw);
-       context_set_address_root(*context, virt_to_phys(domain->pgd));
+       id = domain->id;
+       pgd = domain->pgd;
+
+       if (domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) {
+               int found = 0;
+
+               /* find an available domain id for this device in iommu */
+               ndomains = cap_ndoms(iommu->cap);
+               num = find_first_bit(iommu->domain_ids, ndomains);
+               for (; num < ndomains; ) {
+                       if (iommu->domains[num] == domain) {
+                               id = num;
+                               found = 1;
+                               break;
+                       }
+                       num = find_next_bit(iommu->domain_ids,
+                                           cap_ndoms(iommu->cap), num+1);
+               }
+
+               if (found == 0) {
+                       num = find_first_zero_bit(iommu->domain_ids, ndomains);
+                       if (num >= ndomains) {
+                               spin_unlock_irqrestore(&iommu->lock, flags);
+                               printk(KERN_ERR "IOMMU: no free domain ids\n");
+                               return -EFAULT;
+                       }
+
+                       set_bit(num, iommu->domain_ids);
+                       iommu->domains[num] = domain;
+                       id = num;
+               }
+
+               /* Skip top levels of page tables for
+                * iommu which has less agaw than default.
+                */
+               for (agaw = domain->agaw; agaw != iommu->agaw; agaw--) {
+                       pgd = phys_to_virt(dma_pte_addr(*pgd));
+                       if (!dma_pte_present(*pgd)) {
+                               spin_unlock_irqrestore(&iommu->lock, flags);
+                               return -ENOMEM;
+                       }
+               }
+
+               set_bit(iommu->seq_id, &domain->iommu_bmp);
+       }
+
+       context_set_domain_id(*context, id);
+       context_set_address_width(*context, iommu->agaw);
+       context_set_address_root(*context, virt_to_phys(pgd));
        context_set_translation_type(*context, CONTEXT_TT_MULTI_LEVEL);
        context_set_fault_enable(*context);
        context_set_present(*context);
-- 
1.5.1

0009-change-domain_context_mapping_one-for-virtual-machin.patch
Description: 0009-change-domain_context_mapping_one-for-virtual-machin.patch