intel-iommu: intel_iommu_map_range failed at very end of address space

intel_iommu_map_range() doesn't allow allocation at the very end of the
address space; that code has been simplified and corrected.

Signed-off-by: Tom Lyon <pugs@cisco.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 3 insertions, 8 deletions

diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 57be89e6f484..65741dc491d6 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -3626,7 +3626,6 @@ static int intel_iommu_map_range(struct iommu_domain *domain,
 {
         struct dmar_domain *dmar_domain = domain->priv;
         u64 max_addr;
-        int addr_width;
         int prot = 0;
         int ret;
 
@@ -3639,18 +3638,14 @@ static int intel_iommu_map_range(struct iommu_domain *domain,
 
         max_addr = iova + size;
         if (dmar_domain->max_addr < max_addr) {
-                int min_agaw;
                 u64 end;
 
                 /* check if minimum agaw is sufficient for mapped address */
-                min_agaw = vm_domain_min_agaw(dmar_domain);
-                addr_width = agaw_to_width(min_agaw);
-                end = DOMAIN_MAX_ADDR(addr_width);
-                end = end & VTD_PAGE_MASK;
+                end = __DOMAIN_MAX_ADDR(dmar_domain->gaw) + 1;
                 if (end < max_addr) {
-                        printk(KERN_ERR "%s: iommu agaw (%d) is not "
+                        printk(KERN_ERR "%s: iommu width (%d) is not "
                                "sufficient for the mapped address (%llx)\n",
-                               __func__, min_agaw, max_addr);
+                               __func__, dmar_domain->gaw, max_addr);
                         return -EFAULT;
                 }
                 dmar_domain->max_addr = max_addr;