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Diffstat (limited to 'arch/x86/include/asm/pgtable-3level.h')
| -rw-r--r-- | arch/x86/include/asm/pgtable-3level.h | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/arch/x86/include/asm/pgtable-3level.h b/arch/x86/include/asm/pgtable-3level.h new file mode 100644 index 0000000..fb16cec --- /dev/null +++ b/arch/x86/include/asm/pgtable-3level.h @@ -0,0 +1,175 @@ +#ifndef _ASM_X86_PGTABLE_3LEVEL_H +#define _ASM_X86_PGTABLE_3LEVEL_H + +/* + * Intel Physical Address Extension (PAE) Mode - three-level page + * tables on PPro+ CPUs. + * + * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com> + */ + +#define pte_ERROR(e) \ + printk("%s:%d: bad pte %p(%08lx%08lx).\n", \ + __FILE__, __LINE__, &(e), (e).pte_high, (e).pte_low) +#define pmd_ERROR(e) \ + printk("%s:%d: bad pmd %p(%016Lx).\n", \ + __FILE__, __LINE__, &(e), pmd_val(e)) +#define pgd_ERROR(e) \ + printk("%s:%d: bad pgd %p(%016Lx).\n", \ + __FILE__, __LINE__, &(e), pgd_val(e)) + +static inline int pud_none(pud_t pud) +{ + return pud_val(pud) == 0; +} + +static inline int pud_bad(pud_t pud) +{ + return (pud_val(pud) & ~(PTE_PFN_MASK | _KERNPG_TABLE | _PAGE_USER)) != 0; +} + +static inline int pud_present(pud_t pud) +{ + return pud_val(pud) & _PAGE_PRESENT; +} + +/* Rules for using set_pte: the pte being assigned *must* be + * either not present or in a state where the hardware will + * not attempt to update the pte. In places where this is + * not possible, use pte_get_and_clear to obtain the old pte + * value and then use set_pte to update it. -ben + */ +static inline void native_set_pte(pte_t *ptep, pte_t pte) +{ + ptep->pte_high = pte.pte_high; + smp_wmb(); + ptep->pte_low = pte.pte_low; +} + +/* + * Since this is only called on user PTEs, and the page fault handler + * must handle the already racy situation of simultaneous page faults, + * we are justified in merely clearing the PTE present bit, followed + * by a set. The ordering here is important. + */ +static inline void native_set_pte_present(struct mm_struct *mm, + unsigned long addr, + pte_t *ptep, pte_t pte) +{ + ptep->pte_low = 0; + smp_wmb(); + ptep->pte_high = pte.pte_high; + smp_wmb(); + ptep->pte_low = pte.pte_low; +} + +static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte) +{ + set_64bit((unsigned long long *)(ptep), native_pte_val(pte)); +} + +static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd) +{ + set_64bit((unsigned long long *)(pmdp), native_pmd_val(pmd)); +} + +static inline void native_set_pud(pud_t *pudp, pud_t pud) +{ + set_64bit((unsigned long long *)(pudp), native_pud_val(pud)); +} + +/* + * For PTEs and PDEs, we must clear the P-bit first when clearing a page table + * entry, so clear the bottom half first and enforce ordering with a compiler + * barrier. + */ +static inline void native_pte_clear(struct mm_struct *mm, unsigned long addr, + pte_t *ptep) +{ + ptep->pte_low = 0; + smp_wmb(); + ptep->pte_high = 0; +} + +static inline void native_pmd_clear(pmd_t *pmd) +{ + u32 *tmp = (u32 *)pmd; + *tmp = 0; + smp_wmb(); + *(tmp + 1) = 0; +} + +static inline void pud_clear(pud_t *pudp) +{ + unsigned long pgd; + + set_pud(pudp, __pud(0)); + + /* + * According to Intel App note "TLBs, Paging-Structure Caches, + * and Their Invalidation", April 2007, document 317080-001, + * section 8.1: in PAE mode we explicitly have to flush the + * TLB via cr3 if the top-level pgd is changed... + * + * Make sure the pud entry we're updating is within the + * current pgd to avoid unnecessary TLB flushes. + */ + pgd = read_cr3(); + if (__pa(pudp) >= pgd && __pa(pudp) < + (pgd + sizeof(pgd_t)*PTRS_PER_PGD)) + write_cr3(pgd); +} + +#define pud_page(pud) ((struct page *) __va(pud_val(pud) & PTE_PFN_MASK)) + +#define pud_page_vaddr(pud) ((unsigned long) __va(pud_val(pud) & PTE_PFN_MASK)) + + +/* Find an entry in the second-level page table.. */ +#define pmd_offset(pud, address) ((pmd_t *)pud_page(*(pud)) + \ + pmd_index(address)) + +#ifdef CONFIG_SMP +static inline pte_t native_ptep_get_and_clear(pte_t *ptep) +{ + pte_t res; + + /* xchg acts as a barrier before the setting of the high bits */ + res.pte_low = xchg(&ptep->pte_low, 0); + res.pte_high = ptep->pte_high; + ptep->pte_high = 0; + + return res; +} +#else +#define native_ptep_get_and_clear(xp) native_local_ptep_get_and_clear(xp) +#endif + +#define __HAVE_ARCH_PTE_SAME +static inline int pte_same(pte_t a, pte_t b) +{ + return a.pte_low == b.pte_low && a.pte_high == b.pte_high; +} + +static inline int pte_none(pte_t pte) +{ + return !pte.pte_low && !pte.pte_high; +} + +/* + * Bits 0, 6 and 7 are taken in the low part of the pte, + * put the 32 bits of offset into the high part. + */ +#define pte_to_pgoff(pte) ((pte).pte_high) +#define pgoff_to_pte(off) \ + ((pte_t) { { .pte_low = _PAGE_FILE, .pte_high = (off) } }) +#define PTE_FILE_MAX_BITS 32 + +/* Encode and de-code a swap entry */ +#define __swp_type(x) (((x).val) & 0x1f) +#define __swp_offset(x) ((x).val >> 5) +#define __swp_entry(type, offset) ((swp_entry_t){(type) | (offset) << 5}) +#define __pte_to_swp_entry(pte) ((swp_entry_t){ (pte).pte_high }) +#define __swp_entry_to_pte(x) ((pte_t){ { .pte_high = (x).val } }) + +#endif /* _ASM_X86_PGTABLE_3LEVEL_H */ |