5 files changed, 83 insertions, 5 deletions
diff --git a/arch/arm64/include/asm/page.h b/arch/arm64/include/asm/page.h
index 1cbde2773c4f..cf9afa0366b6 100644
--- a/arch/arm64/include/asm/page.h
+++ b/arch/arm64/include/asm/page.h
@@ -33,19 +33,26 @@
 
 /*
  * The idmap and swapper page tables need some space reserved in the kernel
- * image. Both require a pgd and a next level table to (section) map the
- * kernel. The the swapper also maps the FDT (see __create_page_tables for
+ * image. Both require pgd, pud (4 levels only) and pmd tables to (section)
+ * map the kernel. The swapper also maps the FDT (see __create_page_tables for
  * more information).
  */
+#ifdef CONFIG_ARM64_4_LEVELS
+#define SWAPPER_DIR_SIZE	(3 * PAGE_SIZE)
+#define IDMAP_DIR_SIZE		(3 * PAGE_SIZE)
+#else
 #define SWAPPER_DIR_SIZE	(2 * PAGE_SIZE)
 #define IDMAP_DIR_SIZE		(2 * PAGE_SIZE)
+#endif
 
 #ifndef __ASSEMBLY__
 
 #ifdef CONFIG_ARM64_2_LEVELS
 #include <asm/pgtable-2level-types.h>
-#else
+#elif defined(CONFIG_ARM64_3_LEVELS)
 #include <asm/pgtable-3level-types.h>
+#else
+#include <asm/pgtable-4level-types.h>
 #endif
 
 extern void __cpu_clear_user_page(void *p, unsigned long user);
diff --git a/arch/arm64/include/asm/pgalloc.h b/arch/arm64/include/asm/pgalloc.h
index 48298376e46a..7deb5750a945 100644
--- a/arch/arm64/include/asm/pgalloc.h
+++ b/arch/arm64/include/asm/pgalloc.h
@@ -46,6 +46,26 @@ static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 
 #endif	/* CONFIG_ARM64_2_LEVELS */
 
+#ifdef CONFIG_ARM64_4_LEVELS
+
+static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
+{
+	return (pud_t *)get_zeroed_page(GFP_KERNEL | __GFP_REPEAT);
+}
+
+static inline void pud_free(struct mm_struct *mm, pud_t *pud)
+{
+	BUG_ON((unsigned long)pud & (PAGE_SIZE-1));
+	free_page((unsigned long)pud);
+}
+
+static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
+{
+	set_pgd(pgd, __pgd(__pa(pud) | PUD_TYPE_TABLE));
+}
+
+#endif	/* CONFIG_ARM64_4_LEVELS */
+
 extern pgd_t *pgd_alloc(struct mm_struct *mm);
 extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
 
diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h
index c7c603b489b8..fddcc3efa569 100644
--- a/arch/arm64/include/asm/pgtable-hwdef.h
+++ b/arch/arm64/include/asm/pgtable-hwdef.h
@@ -18,8 +18,10 @@
 
 #ifdef CONFIG_ARM64_2_LEVELS
 #include <asm/pgtable-2level-hwdef.h>
-#else
+#elif defined(CONFIG_ARM64_3_LEVELS)
 #include <asm/pgtable-3level-hwdef.h>
+#else
+#include <asm/pgtable-4level-hwdef.h>
 #endif
 
 /*
@@ -27,7 +29,7 @@
  *
  * Level 1 descriptor (PUD).
  */
-
+#define PUD_TYPE_TABLE		(_AT(pudval_t, 3) << 0)
 #define PUD_TABLE_BIT		(_AT(pgdval_t, 1) << 1)
 #define PUD_TYPE_MASK		(_AT(pgdval_t, 3) << 0)
 #define PUD_TYPE_SECT		(_AT(pgdval_t, 1) << 0)
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 6d5854972a77..d9b23efdaded 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -35,7 +35,11 @@
  * VMALLOC and SPARSEMEM_VMEMMAP ranges.
  */
 #define VMALLOC_START		(UL(0xffffffffffffffff) << VA_BITS)
+#ifndef CONFIG_ARM64_4_LEVELS
 #define VMALLOC_END		(PAGE_OFFSET - UL(0x400000000) - SZ_64K)
+#else
+#define VMALLOC_END		(PAGE_OFFSET - UL(0x40000000000) - SZ_64K)
+#endif
 
 #define vmemmap			((struct page *)(VMALLOC_END + SZ_64K))
 
@@ -44,12 +48,16 @@
 #ifndef __ASSEMBLY__
 extern void __pte_error(const char *file, int line, unsigned long val);
 extern void __pmd_error(const char *file, int line, unsigned long val);
+extern void __pud_error(const char *file, int line, unsigned long val);
 extern void __pgd_error(const char *file, int line, unsigned long val);
 
 #define pte_ERROR(pte)		__pte_error(__FILE__, __LINE__, pte_val(pte))
 #ifndef CONFIG_ARM64_2_LEVELS
 #define pmd_ERROR(pmd)		__pmd_error(__FILE__, __LINE__, pmd_val(pmd))
 #endif
+#ifdef CONFIG_ARM64_4_LEVELS
+#define pud_ERROR(pud)		__pud_error(__FILE__, __LINE__, pud_val(pud))
+#endif
 #define pgd_ERROR(pgd)		__pgd_error(__FILE__, __LINE__, pgd_val(pgd))
 
 #ifdef CONFIG_SMP
@@ -347,6 +355,30 @@ static inline pmd_t *pud_page_vaddr(pud_t pud)
 
 #endif	/* CONFIG_ARM64_2_LEVELS */
 
+#ifdef CONFIG_ARM64_4_LEVELS
+
+#define pgd_none(pgd)		(!pgd_val(pgd))
+#define pgd_bad(pgd)		(!(pgd_val(pgd) & 2))
+#define pgd_present(pgd)	(pgd_val(pgd))
+
+static inline void set_pgd(pgd_t *pgdp, pgd_t pgd)
+{
+	*pgdp = pgd;
+	dsb(ishst);
+}
+
+static inline void pgd_clear(pgd_t *pgdp)
+{
+	set_pgd(pgdp, __pgd(0));
+}
+
+static inline pud_t *pgd_page_vaddr(pgd_t pgd)
+{
+	return __va(pgd_val(pgd) & PHYS_MASK & (s32)PAGE_MASK);
+}
+
+#endif  /* CONFIG_ARM64_4_LEVELS */
+
 /* to find an entry in a page-table-directory */
 #define pgd_index(addr)		(((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
 
@@ -355,6 +387,14 @@ static inline pmd_t *pud_page_vaddr(pud_t pud)
 /* to find an entry in a kernel page-table-directory */
 #define pgd_offset_k(addr)	pgd_offset(&init_mm, addr)
 
+#ifdef CONFIG_ARM64_4_LEVELS
+#define pud_index(addr)		(((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
+static inline pud_t *pud_offset(pgd_t *pgd, unsigned long addr)
+{
+	return (pud_t *)pgd_page_vaddr(*pgd) + pud_index(addr);
+}
+#endif
+
 /* Find an entry in the second-level page table.. */
 #ifndef CONFIG_ARM64_2_LEVELS
 #define pmd_index(addr)		(((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
diff --git a/arch/arm64/include/asm/tlb.h b/arch/arm64/include/asm/tlb.h
index bc19101edaeb..49dc8f03362f 100644
--- a/arch/arm64/include/asm/tlb.h
+++ b/arch/arm64/include/asm/tlb.h
@@ -100,6 +100,15 @@ static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp,
 }
 #endif
 
+#ifdef CONFIG_ARM64_4_LEVELS
+static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pudp,
+				  unsigned long addr)
+{
+	tlb_add_flush(tlb, addr);
+	tlb_remove_page(tlb, virt_to_page(pudp));
+}
+#endif
+
 static inline void __tlb_remove_pmd_tlb_entry(struct mmu_gather *tlb, pmd_t *pmdp,
 						unsigned long address)
 {