diff options
Diffstat (limited to 'arch/x86/include/asm/pgtable-3level.h')
| -rw-r--r-- | arch/x86/include/asm/pgtable-3level.h | 44 |
1 files changed, 42 insertions, 2 deletions
diff --git a/arch/x86/include/asm/pgtable-3level.h b/arch/x86/include/asm/pgtable-3level.h index f24df59c40b2..a564084c6141 100644 --- a/arch/x86/include/asm/pgtable-3level.h +++ b/arch/x86/include/asm/pgtable-3level.h @@ -98,6 +98,9 @@ static inline void native_set_pmd(pmd_t *pmdp, pmd_t pmd) static inline void native_set_pud(pud_t *pudp, pud_t pud) { +#ifdef CONFIG_PAGE_TABLE_ISOLATION + pud.p4d.pgd = pti_set_user_pgtbl(&pudp->p4d.pgd, pud.p4d.pgd); +#endif set_64bit((unsigned long long *)(pudp), native_pud_val(pud)); } @@ -229,6 +232,10 @@ static inline pud_t native_pudp_get_and_clear(pud_t *pudp) { union split_pud res, *orig = (union split_pud *)pudp; +#ifdef CONFIG_PAGE_TABLE_ISOLATION + pti_set_user_pgtbl(&pudp->p4d.pgd, __pgd(0)); +#endif + /* xchg acts as a barrier before setting of the high bits */ res.pud_low = xchg(&orig->pud_low, 0); res.pud_high = orig->pud_high; @@ -241,12 +248,43 @@ static inline pud_t native_pudp_get_and_clear(pud_t *pudp) #endif /* Encode and de-code a swap entry */ +#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 > 5) #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 } }) + +/* + * Normally, __swp_entry() converts from arch-independent swp_entry_t to + * arch-dependent swp_entry_t, and __swp_entry_to_pte() just stores the result + * to pte. But here we have 32bit swp_entry_t and 64bit pte, and need to use the + * whole 64 bits. Thus, we shift the "real" arch-dependent conversion to + * __swp_entry_to_pte() through the following helper macro based on 64bit + * __swp_entry(). + */ +#define __swp_pteval_entry(type, offset) ((pteval_t) { \ + (~(pteval_t)(offset) << SWP_OFFSET_SHIFT >> SWP_TYPE_BITS) \ + | ((pteval_t)(type) << (64 - SWP_TYPE_BITS)) }) + +#define __swp_entry_to_pte(x) ((pte_t){ .pte = \ + __swp_pteval_entry(__swp_type(x), __swp_offset(x)) }) +/* + * Analogically, __pte_to_swp_entry() doesn't just extract the arch-dependent + * swp_entry_t, but also has to convert it from 64bit to the 32bit + * intermediate representation, using the following macros based on 64bit + * __swp_type() and __swp_offset(). + */ +#define __pteval_swp_type(x) ((unsigned long)((x).pte >> (64 - SWP_TYPE_BITS))) +#define __pteval_swp_offset(x) ((unsigned long)(~((x).pte) << SWP_TYPE_BITS >> SWP_OFFSET_SHIFT)) + +#define __pte_to_swp_entry(pte) (__swp_entry(__pteval_swp_type(pte), \ + __pteval_swp_offset(pte))) #define gup_get_pte gup_get_pte /* @@ -295,4 +333,6 @@ static inline pte_t gup_get_pte(pte_t *ptep) return pte; } +#include <asm/pgtable-invert.h> + #endif /* _ASM_X86_PGTABLE_3LEVEL_H */ |