1 files changed, 107 insertions, 1 deletions

diff --git a/arch/riscv/include/asm/pgtable-64.h b/arch/riscv/include/asm/pgtable-64.h
index 228261aa9628..bbbdd66e5e2f 100644
--- a/arch/riscv/include/asm/pgtable-64.h
+++ b/arch/riscv/include/asm/pgtable-64.h
@@ -8,16 +8,36 @@
 
 #include <linux/const.h>
 
-#define PGDIR_SHIFT     30
+extern bool pgtable_l4_enabled;
+
+#define PGDIR_SHIFT_L3  30
+#define PGDIR_SHIFT_L4  39
+#define PGDIR_SIZE_L3   (_AC(1, UL) << PGDIR_SHIFT_L3)
+
+#define PGDIR_SHIFT     (pgtable_l4_enabled ? PGDIR_SHIFT_L4 : PGDIR_SHIFT_L3)
 /* Size of region mapped by a page global directory */
 #define PGDIR_SIZE      (_AC(1, UL) << PGDIR_SHIFT)
 #define PGDIR_MASK      (~(PGDIR_SIZE - 1))
 
+/* pud is folded into pgd in case of 3-level page table */
+#define PUD_SHIFT      30
+#define PUD_SIZE       (_AC(1, UL) << PUD_SHIFT)
+#define PUD_MASK       (~(PUD_SIZE - 1))
+
 #define PMD_SHIFT       21
 /* Size of region mapped by a page middle directory */
 #define PMD_SIZE        (_AC(1, UL) << PMD_SHIFT)
 #define PMD_MASK        (~(PMD_SIZE - 1))
 
+/* Page Upper Directory entry */
+typedef struct {
+	unsigned long pud;
+} pud_t;
+
+#define pud_val(x)      ((x).pud)
+#define __pud(x)        ((pud_t) { (x) })
+#define PTRS_PER_PUD    (PAGE_SIZE / sizeof(pud_t))
+
 /* Page Middle Directory entry */
 typedef struct {
 	unsigned long pmd;
@@ -59,6 +79,16 @@ static inline void pud_clear(pud_t *pudp)
 	set_pud(pudp, __pud(0));
 }
 
+static inline pud_t pfn_pud(unsigned long pfn, pgprot_t prot)
+{
+	return __pud((pfn << _PAGE_PFN_SHIFT) | pgprot_val(prot));
+}
+
+static inline unsigned long _pud_pfn(pud_t pud)
+{
+	return pud_val(pud) >> _PAGE_PFN_SHIFT;
+}
+
 static inline pmd_t *pud_pgtable(pud_t pud)
 {
 	return (pmd_t *)pfn_to_virt(pud_val(pud) >> _PAGE_PFN_SHIFT);
@@ -69,6 +99,17 @@ static inline struct page *pud_page(pud_t pud)
 	return pfn_to_page(pud_val(pud) >> _PAGE_PFN_SHIFT);
 }
 
+#define mm_pud_folded  mm_pud_folded
+static inline bool mm_pud_folded(struct mm_struct *mm)
+{
+	if (pgtable_l4_enabled)
+		return false;
+
+	return true;
+}
+
+#define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
+
 static inline pmd_t pfn_pmd(unsigned long pfn, pgprot_t prot)
 {
 	return __pmd((pfn << _PAGE_PFN_SHIFT) | pgprot_val(prot));
@@ -84,4 +125,69 @@ static inline unsigned long _pmd_pfn(pmd_t pmd)
 #define pmd_ERROR(e) \
 	pr_err("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
 
+#define pud_ERROR(e)   \
+	pr_err("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
+
+static inline void set_p4d(p4d_t *p4dp, p4d_t p4d)
+{
+	if (pgtable_l4_enabled)
+		*p4dp = p4d;
+	else
+		set_pud((pud_t *)p4dp, (pud_t){ p4d_val(p4d) });
+}
+
+static inline int p4d_none(p4d_t p4d)
+{
+	if (pgtable_l4_enabled)
+		return (p4d_val(p4d) == 0);
+
+	return 0;
+}
+
+static inline int p4d_present(p4d_t p4d)
+{
+	if (pgtable_l4_enabled)
+		return (p4d_val(p4d) & _PAGE_PRESENT);
+
+	return 1;
+}
+
+static inline int p4d_bad(p4d_t p4d)
+{
+	if (pgtable_l4_enabled)
+		return !p4d_present(p4d);
+
+	return 0;
+}
+
+static inline void p4d_clear(p4d_t *p4d)
+{
+	if (pgtable_l4_enabled)
+		set_p4d(p4d, __p4d(0));
+}
+
+static inline pud_t *p4d_pgtable(p4d_t p4d)
+{
+	if (pgtable_l4_enabled)
+		return (pud_t *)pfn_to_virt(p4d_val(p4d) >> _PAGE_PFN_SHIFT);
+
+	return (pud_t *)pud_pgtable((pud_t) { p4d_val(p4d) });
+}
+
+static inline struct page *p4d_page(p4d_t p4d)
+{
+	return pfn_to_page(p4d_val(p4d) >> _PAGE_PFN_SHIFT);
+}
+
+#define pud_index(addr) (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
+
+#define pud_offset pud_offset
+static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
+{
+	if (pgtable_l4_enabled)
+		return p4d_pgtable(*p4d) + pud_index(address);
+
+	return (pud_t *)p4d;
+}
+
 #endif /* _ASM_RISCV_PGTABLE_64_H */