1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_file_ops.c b/drivers/infiniband/hw/ipath/ipath_file_ops.c
index bbaa70e57db1..0b6e7679eefd 100644
--- a/drivers/infiniband/hw/ipath/ipath_file_ops.c
+++ b/drivers/infiniband/hw/ipath/ipath_file_ops.c
@@ -985,6 +985,13 @@ static int mmap_piobufs(struct vm_area_struct *vma,
          * write combining behavior we want on the PIO buffers!
          */
 
+#if defined(__powerpc__)
+        /* There isn't a generic way to specify writethrough mappings */
+        pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE;
+        pgprot_val(vma->vm_page_prot) |= _PAGE_WRITETHRU;
+        pgprot_val(vma->vm_page_prot) &= ~_PAGE_GUARDED;
+#endif
+
         if (vma->vm_flags & VM_READ) {
                 dev_info(&dd->pcidev->dev,
                          "Can't map piobufs as readable (flags=%lx)\n",