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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>
#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_MITIGATION_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 remember 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 void cleanup_highmap(void);
#define HAVE_ARCH_UNMAPPED_AREA
#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
#define HAVE_ARCH_UNMAPPED_AREA_VMFLAGS
#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 */
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