1 files changed, 274 insertions, 0 deletions
diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h
new file mode 100644
index 000000000..07cd53eee
--- /dev/null
+++ b/arch/x86/include/asm/pgtable_64.h
@@ -0,0 +1,274 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_PGTABLE_64_H
+#define _ASM_X86_PGTABLE_64_H
+
+#include <linux/const.h>
+#include <asm/pgtable_64_types.h>
+
+#ifndef __ASSEMBLY__
+
+/*
+ * This file contains the functions and defines necessary to modify and use
+ * the x86-64 page table tree.
+ */
+#include <asm/processor.h>
+#include <linux/bitops.h>
+#include <linux/threads.h>
+#include <asm/fixmap.h>
+
+extern p4d_t level4_kernel_pgt[512];
+extern p4d_t level4_ident_pgt[512];
+extern pud_t level3_kernel_pgt[512];
+extern pud_t level3_ident_pgt[512];
+extern pmd_t level2_kernel_pgt[512];
+extern pmd_t level2_fixmap_pgt[512];
+extern pmd_t level2_ident_pgt[512];
+extern pte_t level1_fixmap_pgt[512 * FIXMAP_PMD_NUM];
+extern pgd_t init_top_pgt[];
+
+#define swapper_pg_dir init_top_pgt
+
+extern void paging_init(void);
+static inline void sync_initial_page_table(void) { }
+
+#define pte_ERROR(e)					\
+	pr_err("%s:%d: bad pte %p(%016lx)\n",		\
+	       __FILE__, __LINE__, &(e), pte_val(e))
+#define pmd_ERROR(e)					\
+	pr_err("%s:%d: bad pmd %p(%016lx)\n",		\
+	       __FILE__, __LINE__, &(e), pmd_val(e))
+#define pud_ERROR(e)					\
+	pr_err("%s:%d: bad pud %p(%016lx)\n",		\
+	       __FILE__, __LINE__, &(e), pud_val(e))
+
+#if CONFIG_PGTABLE_LEVELS >= 5
+#define p4d_ERROR(e)					\
+	pr_err("%s:%d: bad p4d %p(%016lx)\n",		\
+	       __FILE__, __LINE__, &(e), p4d_val(e))
+#endif
+
+#define pgd_ERROR(e)					\
+	pr_err("%s:%d: bad pgd %p(%016lx)\n",		\
+	       __FILE__, __LINE__, &(e), pgd_val(e))
+
+struct mm_struct;
+
+#define mm_p4d_folded mm_p4d_folded
+static inline bool mm_p4d_folded(struct mm_struct *mm)
+{
+	return !pgtable_l5_enabled();
+}
+
+void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte);
+void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte);
+
+static inline void native_set_pte(pte_t *ptep, pte_t pte)
+{
+	WRITE_ONCE(*ptep, pte);
+}
+
+static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr,
+				    pte_t *ptep)
+{
+	native_set_pte(ptep, native_make_pte(0));
+}
+
+static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
+{
+	native_set_pte(ptep, pte);
+}
+
+static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd)
+{
+	WRITE_ONCE(*pmdp, pmd);
+}
+
+static inline void native_pmd_clear(pmd_t *pmd)
+{
+	native_set_pmd(pmd, native_make_pmd(0));
+}
+
+static inline pte_t native_ptep_get_and_clear(pte_t *xp)
+{
+#ifdef CONFIG_SMP
+	return native_make_pte(xchg(&xp->pte, 0));
+#else
+	/* native_local_ptep_get_and_clear,
+	   but duplicated because of cyclic dependency */
+	pte_t ret = *xp;
+	native_pte_clear(NULL, 0, xp);
+	return ret;
+#endif
+}
+
+static inline pmd_t native_pmdp_get_and_clear(pmd_t *xp)
+{
+#ifdef CONFIG_SMP
+	return native_make_pmd(xchg(&xp->pmd, 0));
+#else
+	/* native_local_pmdp_get_and_clear,
+	   but duplicated because of cyclic dependency */
+	pmd_t ret = *xp;
+	native_pmd_clear(xp);
+	return ret;
+#endif
+}
+
+static inline void native_set_pud(pud_t *pudp, pud_t pud)
+{
+	WRITE_ONCE(*pudp, pud);
+}
+
+static inline void native_pud_clear(pud_t *pud)
+{
+	native_set_pud(pud, native_make_pud(0));
+}
+
+static inline pud_t native_pudp_get_and_clear(pud_t *xp)
+{
+#ifdef CONFIG_SMP
+	return native_make_pud(xchg(&xp->pud, 0));
+#else
+	/* native_local_pudp_get_and_clear,
+	 * but duplicated because of cyclic dependency
+	 */
+	pud_t ret = *xp;
+
+	native_pud_clear(xp);
+	return ret;
+#endif
+}
+
+static inline void native_set_p4d(p4d_t *p4dp, p4d_t p4d)
+{
+	pgd_t pgd;
+
+	if (pgtable_l5_enabled() || !IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION)) {
+		WRITE_ONCE(*p4dp, p4d);
+		return;
+	}
+
+	pgd = native_make_pgd(native_p4d_val(p4d));
+	pgd = pti_set_user_pgtbl((pgd_t *)p4dp, pgd);
+	WRITE_ONCE(*p4dp, native_make_p4d(native_pgd_val(pgd)));
+}
+
+static inline void native_p4d_clear(p4d_t *p4d)
+{
+	native_set_p4d(p4d, native_make_p4d(0));
+}
+
+static inline void native_set_pgd(pgd_t *pgdp, pgd_t pgd)
+{
+	WRITE_ONCE(*pgdp, pti_set_user_pgtbl(pgdp, pgd));
+}
+
+static inline void native_pgd_clear(pgd_t *pgd)
+{
+	native_set_pgd(pgd, native_make_pgd(0));
+}
+
+/*
+ * Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ */
+
+/* PGD - Level 4 access */
+
+/* PUD - Level 3 access */
+
+/* PMD - Level 2 access */
+
+/* PTE - Level 1 access */
+
+/*
+ * Encode and de-code a swap entry
+ *
+ * |     ...            | 11| 10|  9|8|7|6|5| 4| 3|2| 1|0| <- bit number
+ * |     ...            |SW3|SW2|SW1|G|L|D|A|CD|WT|U| W|P| <- bit names
+ * | TYPE (59-63) | ~OFFSET (9-58)  |0|0|X|X| X| E|F|SD|0| <- swp entry
+ *
+ * G (8) is aliased and used as a PROT_NONE indicator for
+ * !present ptes.  We need to start storing swap entries above
+ * there.  We also need to avoid using A and D because of an
+ * erratum where they can be incorrectly set by hardware on
+ * non-present PTEs.
+ *
+ * SD Bits 1-4 are not used in non-present format and available for
+ * special use described below:
+ *
+ * SD (1) in swp entry is used to store soft dirty bit, which helps us
+ * remember soft dirty over page migration
+ *
+ * F (2) in swp entry is used to record when a pagetable is
+ * writeprotected by userfaultfd WP support.
+ *
+ * E (3) in swp entry is used to rememeber PG_anon_exclusive.
+ *
+ * Bit 7 in swp entry should be 0 because pmd_present checks not only P,
+ * but also L and G.
+ *
+ * The offset is inverted by a binary not operation to make the high
+ * physical bits set.
+ */
+#define SWP_TYPE_BITS		5
+
+#define SWP_OFFSET_FIRST_BIT	(_PAGE_BIT_PROTNONE + 1)
+
+/* We always extract/encode the offset by shifting it all the way up, and then down again */
+#define SWP_OFFSET_SHIFT	(SWP_OFFSET_FIRST_BIT+SWP_TYPE_BITS)
+
+#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS)
+
+/* Extract the high bits for type */
+#define __swp_type(x) ((x).val >> (64 - SWP_TYPE_BITS))
+
+/* Shift up (to get rid of type), then down to get value */
+#define __swp_offset(x) (~(x).val << SWP_TYPE_BITS >> SWP_OFFSET_SHIFT)
+
+/*
+ * Shift the offset up "too far" by TYPE bits, then down again
+ * The offset is inverted by a binary not operation to make the high
+ * physical bits set.
+ */
+#define __swp_entry(type, offset) ((swp_entry_t) { \
+	(~(unsigned long)(offset) << SWP_OFFSET_SHIFT >> SWP_TYPE_BITS) \
+	| ((unsigned long)(type) << (64-SWP_TYPE_BITS)) })
+
+#define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val((pte)) })
+#define __pmd_to_swp_entry(pmd)		((swp_entry_t) { pmd_val((pmd)) })
+#define __swp_entry_to_pte(x)		(__pte((x).val))
+#define __swp_entry_to_pmd(x)		(__pmd((x).val))
+
+extern int kern_addr_valid(unsigned long addr);
+extern void cleanup_highmap(void);
+
+#define HAVE_ARCH_UNMAPPED_AREA
+#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
+
+#define PAGE_AGP    PAGE_KERNEL_NOCACHE
+#define HAVE_PAGE_AGP 1
+
+/* fs/proc/kcore.c */
+#define	kc_vaddr_to_offset(v) ((v) & __VIRTUAL_MASK)
+#define	kc_offset_to_vaddr(o) ((o) | ~__VIRTUAL_MASK)
+
+#define __HAVE_ARCH_PTE_SAME
+
+#define vmemmap ((struct page *)VMEMMAP_START)
+
+extern void init_extra_mapping_uc(unsigned long phys, unsigned long size);
+extern void init_extra_mapping_wb(unsigned long phys, unsigned long size);
+
+#define gup_fast_permitted gup_fast_permitted
+static inline bool gup_fast_permitted(unsigned long start, unsigned long end)
+{
+	if (end >> __VIRTUAL_MASK_SHIFT)
+		return false;
+	return true;
+}
+
+#include <asm/pgtable-invert.h>
+
+#endif /* !__ASSEMBLY__ */
+#endif /* _ASM_X86_PGTABLE_64_H */