diff options
Diffstat (limited to 'arch/powerpc/include/asm/mmu-hash64.h')
| -rw-r--r-- | arch/powerpc/include/asm/mmu-hash64.h | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/mmu-hash64.h b/arch/powerpc/include/asm/mmu-hash64.h index 7514ec2f8540..9d9551840f4a 100644 --- a/arch/powerpc/include/asm/mmu-hash64.h +++ b/arch/powerpc/include/asm/mmu-hash64.h @@ -373,6 +373,38 @@ extern void slb_set_size(u16 size); #ifndef __ASSEMBLY__ +#ifdef CONFIG_PPC_SUBPAGE_PROT +/* + * For the sub-page protection option, we extend the PGD with one of + * these. Basically we have a 3-level tree, with the top level being + * the protptrs array. To optimize speed and memory consumption when + * only addresses < 4GB are being protected, pointers to the first + * four pages of sub-page protection words are stored in the low_prot + * array. + * Each page of sub-page protection words protects 1GB (4 bytes + * protects 64k). For the 3-level tree, each page of pointers then + * protects 8TB. + */ +struct subpage_prot_table { + unsigned long maxaddr; /* only addresses < this are protected */ + unsigned int **protptrs[2]; + unsigned int *low_prot[4]; +}; + +#define SBP_L1_BITS (PAGE_SHIFT - 2) +#define SBP_L2_BITS (PAGE_SHIFT - 3) +#define SBP_L1_COUNT (1 << SBP_L1_BITS) +#define SBP_L2_COUNT (1 << SBP_L2_BITS) +#define SBP_L2_SHIFT (PAGE_SHIFT + SBP_L1_BITS) +#define SBP_L3_SHIFT (SBP_L2_SHIFT + SBP_L2_BITS) + +extern void subpage_prot_free(struct mm_struct *mm); +extern void subpage_prot_init_new_context(struct mm_struct *mm); +#else +static inline void subpage_prot_free(pgd_t *pgd) {} +static inline void subpage_prot_init_new_context(struct mm_struct *mm) { } +#endif /* CONFIG_PPC_SUBPAGE_PROT */ + typedef unsigned long mm_context_id_t; typedef struct { @@ -386,6 +418,9 @@ typedef struct { u16 sllp; /* SLB page size encoding */ #endif unsigned long vdso_base; +#ifdef CONFIG_PPC_SUBPAGE_PROT + struct subpage_prot_table spt; +#endif /* CONFIG_PPC_SUBPAGE_PROT */ } mm_context_t; |