4 files changed, 18 insertions, 15 deletions

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 74697408576f..22d7d050905d 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -29,9 +29,6 @@
 
 #define CMD_SET_TYPE(cmd, t) ((cmd)->data[1] |= ((t) << 28))
 
-#define to_pages(addr, size) \
-         (round_up(((addr) & ~PAGE_MASK) + (size), PAGE_SIZE) >> PAGE_SHIFT)
-
 #define EXIT_LOOP_COUNT 10000000
 
 static DEFINE_RWLOCK(amd_iommu_devtable_lock);
@@ -185,7 +182,7 @@ static int iommu_flush_pages(struct amd_iommu *iommu, u16 domid,
                 u64 address, size_t size)
 {
         int s = 0;
-        unsigned pages = to_pages(address, size);
+        unsigned pages = iommu_num_pages(address, size);
 
         address &= PAGE_MASK;
 
@@ -557,8 +554,8 @@ static struct dma_ops_domain *dma_ops_domain_alloc(struct amd_iommu *iommu,
         if (iommu->exclusion_start &&
             iommu->exclusion_start < dma_dom->aperture_size) {
                 unsigned long startpage = iommu->exclusion_start >> PAGE_SHIFT;
-                int pages = to_pages(iommu->exclusion_start,
-                                iommu->exclusion_length);
+                int pages = iommu_num_pages(iommu->exclusion_start,
+                                            iommu->exclusion_length);
                 dma_ops_reserve_addresses(dma_dom, startpage, pages);
         }
 
@@ -767,7 +764,7 @@ static dma_addr_t __map_single(struct device *dev,
         unsigned int pages;
         int i;
 
-        pages = to_pages(paddr, size);
+        pages = iommu_num_pages(paddr, size);
         paddr &= PAGE_MASK;
 
         address = dma_ops_alloc_addresses(dev, dma_dom, pages);
@@ -802,7 +799,7 @@ static void __unmap_single(struct amd_iommu *iommu,
         if ((dma_addr == 0) || (dma_addr + size > dma_dom->aperture_size))
                 return;
 
-        pages = to_pages(dma_addr, size);
+        pages = iommu_num_pages(dma_addr, size);
         dma_addr &= PAGE_MASK;
         start = dma_addr;
 
diff --git a/arch/x86/kernel/pci-gart_64.c b/arch/x86/kernel/pci-gart_64.c
index 744126e64950..49285f8fd4d5 100644
--- a/arch/x86/kernel/pci-gart_64.c
+++ b/arch/x86/kernel/pci-gart_64.c
@@ -67,9 +67,6 @@ static u32 gart_unmapped_entry;
         (((x) & 0xfffff000) | (((x) >> 32) << 4) | GPTE_VALID | GPTE_COHERENT)
 #define GPTE_DECODE(x) (((x) & 0xfffff000) | (((u64)(x) & 0xff0) << 28))
 
-#define to_pages(addr, size) \
-        (round_up(((addr) & ~PAGE_MASK) + (size), PAGE_SIZE) >> PAGE_SHIFT)
-
 #define EMERGENCY_PAGES 32 /* = 128KB */
 
 #ifdef CONFIG_AGP
@@ -241,7 +238,7 @@ nonforced_iommu(struct device *dev, unsigned long addr, size_t size)
 static dma_addr_t dma_map_area(struct device *dev, dma_addr_t phys_mem,
                                 size_t size, int dir)
 {
-        unsigned long npages = to_pages(phys_mem, size);
+        unsigned long npages = iommu_num_pages(phys_mem, size);
         unsigned long iommu_page = alloc_iommu(dev, npages);
         int i;
 
@@ -304,7 +301,7 @@ static void gart_unmap_single(struct device *dev, dma_addr_t dma_addr,
                 return;
 
         iommu_page = (dma_addr - iommu_bus_base)>>PAGE_SHIFT;
-        npages = to_pages(dma_addr, size);
+        npages = iommu_num_pages(dma_addr, size);
         for (i = 0; i < npages; i++) {
                 iommu_gatt_base[iommu_page + i] = gart_unmapped_entry;
                 CLEAR_LEAK(iommu_page + i);
@@ -387,7 +384,7 @@ static int __dma_map_cont(struct device *dev, struct scatterlist *start,
                 }
 
                 addr = phys_addr;
-                pages = to_pages(s->offset, s->length);
+                pages = iommu_num_pages(s->offset, s->length);
                 while (pages--) {
                         iommu_gatt_base[iommu_page] = GPTE_ENCODE(addr);
                         SET_LEAK(iommu_page);
@@ -470,7 +467,7 @@ gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
 
                 seg_size += s->length;
                 need = nextneed;
-                pages += to_pages(s->offset, s->length);
+                pages += iommu_num_pages(s->offset, s->length);
                 ps = s;
         }
         if (dma_map_cont(dev, start_sg, i - start, sgmap, pages, need) < 0)
diff --git a/include/linux/iommu-helper.h b/include/linux/iommu-helper.h
index c975caf75385..f8598f583944 100644
--- a/include/linux/iommu-helper.h
+++ b/include/linux/iommu-helper.h
@@ -8,3 +8,4 @@ extern unsigned long iommu_area_alloc(unsigned long *map, unsigned long size,
                                       unsigned long align_mask);
 extern void iommu_area_free(unsigned long *map, unsigned long start,
                             unsigned int nr);
+extern unsigned long iommu_num_pages(unsigned long addr, unsigned long len);
diff --git a/lib/iommu-helper.c b/lib/iommu-helper.c
index a3b8d4c3f77a..889ddce2021e 100644
--- a/lib/iommu-helper.c
+++ b/lib/iommu-helper.c
@@ -80,3 +80,11 @@ void iommu_area_free(unsigned long *map, unsigned long start, unsigned int nr)
         }
 }
 EXPORT_SYMBOL(iommu_area_free);
+
+unsigned long iommu_num_pages(unsigned long addr, unsigned long len)
+{
+        unsigned long size = roundup((addr & ~PAGE_MASK) + len, PAGE_SIZE);
+
+        return size >> PAGE_SHIFT;
+}
+EXPORT_SYMBOL(iommu_num_pages);