intel-iommu: Make dma_pte_free_pagetable() use pfns

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 22 insertions, 18 deletions

diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index ff8b7ce4a013..1526864a9d6f 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -669,27 +669,27 @@ static inline int width_to_agaw(int width)
 
 static inline unsigned int level_to_offset_bits(int level)
 {
-        return (12 + (level - 1) * LEVEL_STRIDE);
+        return (level - 1) * LEVEL_STRIDE;
 }
 
 static inline int pfn_level_offset(unsigned long pfn, int level)
 {
-        return (pfn >> (level_to_offset_bits(level) - 12)) & LEVEL_MASK;
+        return (pfn >> level_to_offset_bits(level)) & LEVEL_MASK;
 }
 
-static inline u64 level_mask(int level)
+static inline unsigned long level_mask(int level)
 {
-        return ((u64)-1 << level_to_offset_bits(level));
+        return -1UL << level_to_offset_bits(level);
 }
 
-static inline u64 level_size(int level)
+static inline unsigned long level_size(int level)
 {
-        return ((u64)1 << level_to_offset_bits(level));
+        return 1UL << level_to_offset_bits(level);
 }
 
-static inline u64 align_to_level(u64 addr, int level)
+static inline unsigned long align_to_level(unsigned long pfn, int level)
 {
-        return ((addr + level_size(level) - 1) & level_mask(level));
+        return (pfn + level_size(level) - 1) & level_mask(level);
 }
 
 static struct dma_pte * addr_to_dma_pte(struct dmar_domain *domain, u64 addr)
@@ -798,25 +798,29 @@ static void dma_pte_clear_range(struct dmar_domain *domain,
 static void dma_pte_free_pagetable(struct dmar_domain *domain,
         u64 start, u64 end)
 {
-        int addr_width = agaw_to_width(domain->agaw);
+        int addr_width = agaw_to_width(domain->agaw) - VTD_PAGE_SHIFT;
+        unsigned long start_pfn = start >> VTD_PAGE_SHIFT;
+        unsigned long last_pfn = (end-1) >> VTD_PAGE_SHIFT;
         struct dma_pte *pte;
         int total = agaw_to_level(domain->agaw);
         int level;
-        u64 tmp;
+        unsigned long tmp;
 
-        BUG_ON(start >> addr_width);
-        BUG_ON(end >> addr_width);
+        BUG_ON(addr_width < BITS_PER_LONG && start_pfn >> addr_width);
+        BUG_ON(addr_width < BITS_PER_LONG && last_pfn >> addr_width);
 
         /* we don't need lock here, nobody else touches the iova range */
         level = 2;
         while (level <= total) {
-                tmp = align_to_level(start, level);
-                if (tmp >= end || (tmp + level_size(level) > end))
+                tmp = align_to_level(start_pfn, level);
+
+                /* Only clear this pte/pmd if we're asked to clear its
+                   _whole_ range */
+                if (tmp + level_size(level) - 1 > last_pfn)
                         return;
 
-                while (tmp < end) {
-                        pte = dma_pfn_level_pte(domain, tmp >> VTD_PAGE_SHIFT,
-                                                level);
+                while (tmp <= last_pfn) {
+                        pte = dma_pfn_level_pte(domain, tmp, level);
                         if (pte) {
                                 free_pgtable_page(
                                         phys_to_virt(dma_pte_addr(pte)));
@@ -828,7 +832,7 @@ static void dma_pte_free_pagetable(struct dmar_domain *domain,
                 level++;
         }
         /* free pgd */
-        if (start == 0 && end >= ((((u64)1) << addr_width) - 1)) {
+        if (start == 0 && last_pfn == DOMAIN_MAX_PFN(domain->gaw)) {
                 free_pgtable_page(domain->pgd);
                 domain->pgd = NULL;
         }