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-rw-r--r--arch/x86/include/asm/pgtable-2level.h131
1 files changed, 131 insertions, 0 deletions
diff --git a/arch/x86/include/asm/pgtable-2level.h b/arch/x86/include/asm/pgtable-2level.h
new file mode 100644
index 0000000000..e9482a11ac
--- /dev/null
+++ b/arch/x86/include/asm/pgtable-2level.h
@@ -0,0 +1,131 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_PGTABLE_2LEVEL_H
+#define _ASM_X86_PGTABLE_2LEVEL_H
+
+#define pte_ERROR(e) \
+ pr_err("%s:%d: bad pte %08lx\n", __FILE__, __LINE__, (e).pte_low)
+#define pgd_ERROR(e) \
+ pr_err("%s:%d: bad pgd %08lx\n", __FILE__, __LINE__, pgd_val(e))
+
+/*
+ * Certain architectures need to do special things when PTEs
+ * within a page table are directly modified. Thus, the following
+ * hook is made available.
+ */
+static inline void native_set_pte(pte_t *ptep , pte_t pte)
+{
+ *ptep = pte;
+}
+
+static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd)
+{
+ *pmdp = pmd;
+}
+
+static inline void native_set_pud(pud_t *pudp, pud_t pud)
+{
+}
+
+static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
+{
+ native_set_pte(ptep, pte);
+}
+
+static inline void native_pmd_clear(pmd_t *pmdp)
+{
+ native_set_pmd(pmdp, __pmd(0));
+}
+
+static inline void native_pud_clear(pud_t *pudp)
+{
+}
+
+static inline void native_pte_clear(struct mm_struct *mm,
+ unsigned long addr, pte_t *xp)
+{
+ *xp = native_make_pte(0);
+}
+
+#ifdef CONFIG_SMP
+static inline pte_t native_ptep_get_and_clear(pte_t *xp)
+{
+ return __pte(xchg(&xp->pte_low, 0));
+}
+#else
+#define native_ptep_get_and_clear(xp) native_local_ptep_get_and_clear(xp)
+#endif
+
+#ifdef CONFIG_SMP
+static inline pmd_t native_pmdp_get_and_clear(pmd_t *xp)
+{
+ return __pmd(xchg((pmdval_t *)xp, 0));
+}
+#else
+#define native_pmdp_get_and_clear(xp) native_local_pmdp_get_and_clear(xp)
+#endif
+
+#ifdef CONFIG_SMP
+static inline pud_t native_pudp_get_and_clear(pud_t *xp)
+{
+ return __pud(xchg((pudval_t *)xp, 0));
+}
+#else
+#define native_pudp_get_and_clear(xp) native_local_pudp_get_and_clear(xp)
+#endif
+
+/* Bit manipulation helper on pte/pgoff entry */
+static inline unsigned long pte_bitop(unsigned long value, unsigned int rightshift,
+ unsigned long mask, unsigned int leftshift)
+{
+ return ((value >> rightshift) & mask) << leftshift;
+}
+
+/*
+ * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
+ * are !pte_none() && !pte_present().
+ *
+ * Format of swap PTEs:
+ *
+ * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
+ * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
+ * <----------------- offset ------------------> 0 E <- type --> 0
+ *
+ * E is the exclusive marker that is not stored in swap entries.
+ */
+#define SWP_TYPE_BITS 5
+#define _SWP_TYPE_MASK ((1U << SWP_TYPE_BITS) - 1)
+#define _SWP_TYPE_SHIFT (_PAGE_BIT_PRESENT + 1)
+#define SWP_OFFSET_SHIFT (_PAGE_BIT_PROTNONE + 1)
+
+#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > 5)
+
+#define __swp_type(x) (((x).val >> _SWP_TYPE_SHIFT) \
+ & _SWP_TYPE_MASK)
+#define __swp_offset(x) ((x).val >> SWP_OFFSET_SHIFT)
+#define __swp_entry(type, offset) ((swp_entry_t) { \
+ (((type) & _SWP_TYPE_MASK) << _SWP_TYPE_SHIFT) \
+ | ((offset) << SWP_OFFSET_SHIFT) })
+#define __pte_to_swp_entry(pte) ((swp_entry_t) { (pte).pte_low })
+#define __swp_entry_to_pte(x) ((pte_t) { .pte = (x).val })
+
+/* We borrow bit 7 to store the exclusive marker in swap PTEs. */
+#define _PAGE_SWP_EXCLUSIVE _PAGE_PSE
+
+/* No inverted PFNs on 2 level page tables */
+
+static inline u64 protnone_mask(u64 val)
+{
+ return 0;
+}
+
+static inline u64 flip_protnone_guard(u64 oldval, u64 val, u64 mask)
+{
+ return val;
+}
+
+static inline bool __pte_needs_invert(u64 val)
+{
+ return false;
+}
+
+#endif /* _ASM_X86_PGTABLE_2LEVEL_H */