mm: fix pfn_t vs highmem

[deliverable/linux.git] / include / linux / pfn.h

diff --git a/include/linux/pfn.h b/include/linux/pfn.h
index 97f3e88aead4acbb7dcb5e3ac4cf2c9e03885e6a..1132953235c0708bd87e1b9eea777bb705f54cb3 100644 (file)
--- a/include/linux/pfn.h
+++ b/include/linux/pfn.h
@@ -3,6 +3,15 @@
 
 #ifndef __ASSEMBLY__
 #include <linux/types.h>
+
+/*
+ * pfn_t: encapsulates a page-frame number that is optionally backed
+ * by memmap (struct page).  Whether a pfn_t has a 'struct page'
+ * backing is indicated by flags in the high bits of the value.
+ */
+typedef struct {
+       u64 val;
+} pfn_t;
 #endif
 
 #define PFN_ALIGN(x)   (((unsigned long)(x) + (PAGE_SIZE - 1)) & PAGE_MASK)