diff options
Diffstat (limited to 'arch/s390/include/asm/pgtable.h')
| -rw-r--r-- | arch/s390/include/asm/pgtable.h | 75 |
1 files changed, 11 insertions, 64 deletions
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 02ace3491c5..763620ec792 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -256,8 +256,6 @@ extern unsigned long VMALLOC_START; #define _PAGE_TYPE_FILE 0x601 /* bit 0x002 is used for offset !! */ #define _PAGE_TYPE_RO 0x200 #define _PAGE_TYPE_RW 0x000 -#define _PAGE_TYPE_EX_RO 0x202 -#define _PAGE_TYPE_EX_RW 0x002 /* * Only four types for huge pages, using the invalid bit and protection bit @@ -287,8 +285,6 @@ extern unsigned long VMALLOC_START; * _PAGE_TYPE_FILE 11?1 -> 11?1 * _PAGE_TYPE_RO 0100 -> 1100 * _PAGE_TYPE_RW 0000 -> 1000 - * _PAGE_TYPE_EX_RO 0110 -> 1110 - * _PAGE_TYPE_EX_RW 0010 -> 1010 * * pte_none is true for bits combinations 1000, 1010, 1100, 1110 * pte_present is true for bits combinations 0000, 0010, 0100, 0110, 1001 @@ -387,55 +383,33 @@ extern unsigned long VMALLOC_START; #define PAGE_NONE __pgprot(_PAGE_TYPE_NONE) #define PAGE_RO __pgprot(_PAGE_TYPE_RO) #define PAGE_RW __pgprot(_PAGE_TYPE_RW) -#define PAGE_EX_RO __pgprot(_PAGE_TYPE_EX_RO) -#define PAGE_EX_RW __pgprot(_PAGE_TYPE_EX_RW) #define PAGE_KERNEL PAGE_RW #define PAGE_COPY PAGE_RO /* - * Dependent on the EXEC_PROTECT option s390 can do execute protection. - * Write permission always implies read permission. In theory with a - * primary/secondary page table execute only can be implemented but - * it would cost an additional bit in the pte to distinguish all the - * different pte types. To avoid that execute permission currently - * implies read permission as well. + * On s390 the page table entry has an invalid bit and a read-only bit. + * Read permission implies execute permission and write permission + * implies read permission. */ /*xwr*/ #define __P000 PAGE_NONE #define __P001 PAGE_RO #define __P010 PAGE_RO #define __P011 PAGE_RO -#define __P100 PAGE_EX_RO -#define __P101 PAGE_EX_RO -#define __P110 PAGE_EX_RO -#define __P111 PAGE_EX_RO +#define __P100 PAGE_RO +#define __P101 PAGE_RO +#define __P110 PAGE_RO +#define __P111 PAGE_RO #define __S000 PAGE_NONE #define __S001 PAGE_RO #define __S010 PAGE_RW #define __S011 PAGE_RW -#define __S100 PAGE_EX_RO -#define __S101 PAGE_EX_RO -#define __S110 PAGE_EX_RW -#define __S111 PAGE_EX_RW - -#ifndef __s390x__ -# define PxD_SHADOW_SHIFT 1 -#else /* __s390x__ */ -# define PxD_SHADOW_SHIFT 2 -#endif /* __s390x__ */ - -static inline void *get_shadow_table(void *table) -{ - unsigned long addr, offset; - struct page *page; - - addr = (unsigned long) table; - offset = addr & ((PAGE_SIZE << PxD_SHADOW_SHIFT) - 1); - page = virt_to_page((void *)(addr ^ offset)); - return (void *)(addr_t)(page->index ? (page->index | offset) : 0UL); -} +#define __S100 PAGE_RO +#define __S101 PAGE_RO +#define __S110 PAGE_RW +#define __S111 PAGE_RW /* * Certain architectures need to do special things when PTEs @@ -446,14 +420,6 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t entry) { *ptep = entry; - if (mm->context.noexec) { - if (!(pte_val(entry) & _PAGE_INVALID) && - (pte_val(entry) & _PAGE_SWX)) - pte_val(entry) |= _PAGE_RO; - else - pte_val(entry) = _PAGE_TYPE_EMPTY; - ptep[PTRS_PER_PTE] = entry; - } } /* @@ -662,11 +628,7 @@ static inline void pgd_clear_kernel(pgd_t * pgd) static inline void pgd_clear(pgd_t * pgd) { - pgd_t *shadow = get_shadow_table(pgd); - pgd_clear_kernel(pgd); - if (shadow) - pgd_clear_kernel(shadow); } static inline void pud_clear_kernel(pud_t *pud) @@ -677,13 +639,8 @@ static inline void pud_clear_kernel(pud_t *pud) static inline void pud_clear(pud_t *pud) { - pud_t *shadow = get_shadow_table(pud); - pud_clear_kernel(pud); - if (shadow) - pud_clear_kernel(shadow); } - #endif /* __s390x__ */ static inline void pmd_clear_kernel(pmd_t * pmdp) @@ -693,18 +650,12 @@ static inline void pmd_clear_kernel(pmd_t * pmdp) static inline void pmd_clear(pmd_t *pmd) { - pmd_t *shadow = get_shadow_table(pmd); - pmd_clear_kernel(pmd); - if (shadow) - pmd_clear_kernel(shadow); } static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { pte_val(*ptep) = _PAGE_TYPE_EMPTY; - if (mm->context.noexec) - pte_val(ptep[PTRS_PER_PTE]) = _PAGE_TYPE_EMPTY; } /* @@ -903,10 +854,6 @@ static inline void ptep_invalidate(struct mm_struct *mm, } __ptep_ipte(address, ptep); pte_val(*ptep) = _PAGE_TYPE_EMPTY; - if (mm->context.noexec) { - __ptep_ipte(address, ptep + PTRS_PER_PTE); - pte_val(*(ptep + PTRS_PER_PTE)) = _PAGE_TYPE_EMPTY; - } } /* |