ARM: Add page table and page defines needed by KVM

KVM uses the stage-2 page tables and the Hyp page table format,
so we define the fields and page protection flags needed by KVM.

The nomenclature is this:
 - page_hyp:        PL2 code/data mappings
 - page_hyp_device: PL2 device mappings (vgic access)
 - page_s2:         Stage-2 code/data page mappings
 - page_s2_device:  Stage-2 device mappings (vgic access)

Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Christoffer Dall <c.dall@virtualopensystems.com>
diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
index a3f3792..6ef8afd 100644
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h
@@ -104,11 +104,29 @@
  */
 #define L_PGD_SWAPPER		(_AT(pgdval_t, 1) << 55)	/* swapper_pg_dir entry */
 
+/*
+ * 2nd stage PTE definitions for LPAE.
+ */
+#define L_PTE_S2_MT_UNCACHED	 (_AT(pteval_t, 0x5) << 2) /* MemAttr[3:0] */
+#define L_PTE_S2_MT_WRITETHROUGH (_AT(pteval_t, 0xa) << 2) /* MemAttr[3:0] */
+#define L_PTE_S2_MT_WRITEBACK	 (_AT(pteval_t, 0xf) << 2) /* MemAttr[3:0] */
+#define L_PTE_S2_RDONLY		 (_AT(pteval_t, 1) << 6)   /* HAP[1]   */
+#define L_PTE_S2_RDWR		 (_AT(pteval_t, 2) << 6)   /* HAP[2:1] */
+
+/*
+ * Hyp-mode PL2 PTE definitions for LPAE.
+ */
+#define L_PTE_HYP		L_PTE_USER
+
 #ifndef __ASSEMBLY__
 
 #define pud_none(pud)		(!pud_val(pud))
 #define pud_bad(pud)		(!(pud_val(pud) & 2))
 #define pud_present(pud)	(pud_val(pud))
+#define pmd_table(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
+						 PMD_TYPE_TABLE)
+#define pmd_sect(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
+						 PMD_TYPE_SECT)
 
 #define pud_clear(pudp)			\
 	do {				\