[PATCH v2 2/6] mm: Introduce pXX_leaf_size()

[Peter Zijlstra]

A number of architectures have non-pagetable aligned huge/large pages.
For such architectures a leaf can actually be part of a larger entry.

Provide generic helpers to determine the size of a page-table leaf.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
 include/linux/pgtable.h |   16 ++++++++++++++++
 1 file changed, 16 insertions(+)

--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -1536,4 +1536,20 @@ typedef unsigned int pgtbl_mod_mask;
 #define pmd_leaf(x)	0
 #endif
 
+#ifndef pgd_leaf_size
+#define pgd_leaf_size(x) (1ULL << PGDIR_SHIFT)
+#endif
+#ifndef p4d_leaf_size
+#define p4d_leaf_size(x) P4D_SIZE
+#endif
+#ifndef pud_leaf_size
+#define pud_leaf_size(x) PUD_SIZE
+#endif
+#ifndef pmd_leaf_size
+#define pmd_leaf_size(x) PMD_SIZE
+#endif
+#ifndef pte_leaf_size
+#define pte_leaf_size(x) PAGE_SIZE
+#endif
+
 #endif /* _LINUX_PGTABLE_H */