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/* 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>
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];
extern pgd_t init_top_pgt[];
#define swapper_pg_dir init_top_pgt
extern void paging_init(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;
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_pte_clear(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
*ptep = native_make_pte(0);
}
static inline void native_set_pte(pte_t *ptep, pte_t pte)
{
*ptep = pte;
}
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)
{
*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)
{
*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
}
#ifdef CONFIG_PAGE_TABLE_ISOLATION
/*
* All top-level PAGE_TABLE_ISOLATION page tables are order-1 pages
* (8k-aligned and 8k in size). The kernel one is at the beginning 4k and
* the user one is in the last 4k. To switch between them, you
* just need to flip the 12th bit in their addresses.
*/
#define PTI_PGTABLE_SWITCH_BIT PAGE_SHIFT
/*
* This generates better code than the inline assembly in
* __set_bit().
*/
static inline void *ptr_set_bit(void *ptr, int bit)
{
unsigned long __ptr = (unsigned long)ptr;
__ptr |= BIT(bit);
return (void *)__ptr;
}
static inline void *ptr_clear_bit(void *ptr, int bit)
{
unsigned long __ptr = (unsigned long)ptr;
__ptr &= ~BIT(bit);
return (void *)__ptr;
}
static inline pgd_t *kernel_to_user_pgdp(pgd_t *pgdp)
{
return ptr_set_bit(pgdp, PTI_PGTABLE_SWITCH_BIT);
}
static inline pgd_t *user_to_kernel_pgdp(pgd_t *pgdp)
{
return ptr_clear_bit(pgdp, PTI_PGTABLE_SWITCH_BIT);
}
static inline p4d_t *kernel_to_user_p4dp(p4d_t *p4dp)
{
return ptr_set_bit(p4dp, PTI_PGTABLE_SWITCH_BIT);
}
static inline p4d_t *user_to_kernel_p4dp(p4d_t *p4dp)
{
return ptr_clear_bit(p4dp, PTI_PGTABLE_SWITCH_BIT);
}
#endif /* CONFIG_PAGE_TABLE_ISOLATION */
/*
* Page table pages are page-aligned. The lower half of the top
* level is used for userspace and the top half for the kernel.
*
* Returns true for parts of the PGD that map userspace and
* false for the parts that map the kernel.
*/
static inline bool pgdp_maps_userspace(void *__ptr)
{
unsigned long ptr = (unsigned long)__ptr;
return (ptr & ~PAGE_MASK) < (PAGE_SIZE / 2);
}
#ifdef CONFIG_PAGE_TABLE_ISOLATION
pgd_t __pti_set_user_pgd(pgd_t *pgdp, pgd_t pgd);
/*
* Take a PGD location (pgdp) and a pgd value that needs to be set there.
* Populates the user and returns the resulting PGD that must be set in
* the kernel copy of the page tables.
*/
static inline pgd_t pti_set_user_pgd(pgd_t *pgdp, pgd_t pgd)
{
if (!static_cpu_has(X86_FEATURE_PTI))
return pgd;
return __pti_set_user_pgd(pgdp, pgd);
}
#else
static inline pgd_t pti_set_user_pgd(pgd_t *pgdp, pgd_t pgd)
{
return pgd;
}
#endif
static inline void native_set_p4d(p4d_t *p4dp, p4d_t p4d)
{
#if defined(CONFIG_PAGE_TABLE_ISOLATION) && !defined(CONFIG_X86_5LEVEL)
p4dp->pgd = pti_set_user_pgd(&p4dp->pgd, p4d.pgd);
#else
*p4dp = p4d;
#endif
}
static inline void native_p4d_clear(p4d_t *p4d)
{
#ifdef CONFIG_X86_5LEVEL
native_set_p4d(p4d, native_make_p4d(0));
#else
native_set_p4d(p4d, (p4d_t) { .pgd = native_make_pgd(0)});
#endif
}
static inline void native_set_pgd(pgd_t *pgdp, pgd_t pgd)
{
#ifdef CONFIG_PAGE_TABLE_ISOLATION
*pgdp = pti_set_user_pgd(pgdp, pgd);
#else
*pgdp = pgd;
#endif
}
static inline void native_pgd_clear(pgd_t *pgd)
{
native_set_pgd(pgd, native_make_pgd(0));
}
extern void sync_global_pgds(unsigned long start, unsigned long end);
/*
* Conversion functions: convert a page and protection to a page entry,
* and a page entry and page directory to the page they refer to.
*/
/*
* Level 4 access.
*/
static inline int pgd_large(pgd_t pgd) { return 0; }
#define mk_kernel_pgd(address) __pgd((address) | _KERNPG_TABLE)
/* PUD - Level3 access */
/* PMD - Level 2 access */
/* PTE - Level 1 access. */
/* x86-64 always has all page tables mapped. */
#define pte_offset_map(dir, address) pte_offset_kernel((dir), (address))
#define pte_unmap(pte) ((void)(pte))/* NOP */
/*
* 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
* | OFFSET (14->63) | TYPE (9-13) |0|0|X|X| X| X|X|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 (1) in swp entry is used to store soft dirty bit, which helps us
* remember soft dirty over page migration
*
* Bit 7 in swp entry should be 0 because pmd_present checks not only P,
* but also L and G.
*/
#define SWP_TYPE_FIRST_BIT (_PAGE_BIT_PROTNONE + 1)
#define SWP_TYPE_BITS 5
/* Place the offset above the type: */
#define SWP_OFFSET_FIRST_BIT (SWP_TYPE_FIRST_BIT + SWP_TYPE_BITS)
#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS)
#define __swp_type(x) (((x).val >> (SWP_TYPE_FIRST_BIT)) \
& ((1U << SWP_TYPE_BITS) - 1))
#define __swp_offset(x) ((x).val >> SWP_OFFSET_FIRST_BIT)
#define __swp_entry(type, offset) ((swp_entry_t) { \
((type) << (SWP_TYPE_FIRST_BIT)) \
| ((offset) << SWP_OFFSET_FIRST_BIT) })
#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_t) { .pte = (x).val })
#define __swp_entry_to_pmd(x) ((pmd_t) { .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 pgtable_cache_init() do { } while (0)
#define check_pgt_cache() do { } while (0)
#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, int nr_pages,
int write)
{
unsigned long len, end;
len = (unsigned long)nr_pages << PAGE_SHIFT;
end = start + len;
if (end < start)
return false;
if (end >> __VIRTUAL_MASK_SHIFT)
return false;
return true;
}
#endif /* !__ASSEMBLY__ */
#endif /* _ASM_X86_PGTABLE_64_H */