diff options
Diffstat (limited to 'arch/powerpc/mm/book3s32')
| -rw-r--r-- | arch/powerpc/mm/book3s32/mmu_context.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/arch/powerpc/mm/book3s32/mmu_context.c b/arch/powerpc/mm/book3s32/mmu_context.c index c949363f315f..e2708e387dc3 100644 --- a/arch/powerpc/mm/book3s32/mmu_context.c +++ b/arch/powerpc/mm/book3s32/mmu_context.c @@ -24,6 +24,12 @@ #include <asm/mmu_context.h> /* + * Room for two PTE pointers, usually the kernel and current user pointers + * to their respective root page table. + */ +void *abatron_pteptrs[2]; + +/* * On 32-bit PowerPC 6xx/7xx/7xxx CPUs, we use a set of 16 VSIDs * (virtual segment identifiers) for each context. Although the * hardware supports 24-bit VSIDs, and thus >1 million contexts, @@ -98,3 +104,32 @@ void __init mmu_context_init(void) context_map[0] = (1 << FIRST_CONTEXT) - 1; next_mmu_context = FIRST_CONTEXT; } + +void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk) +{ + long id = next->context.id; + unsigned long val; + + if (id < 0) + panic("mm_struct %p has no context ID", next); + + isync(); + + val = CTX_TO_VSID(id, 0); + if (!kuep_is_disabled()) + val |= SR_NX; + if (!kuap_is_disabled()) + val |= SR_KS; + + update_user_segments(val); + + if (IS_ENABLED(CONFIG_BDI_SWITCH)) + abatron_pteptrs[1] = next->pgd; + + if (!mmu_has_feature(MMU_FTR_HPTE_TABLE)) + mtspr(SPRN_SDR1, rol32(__pa(next->pgd), 4) & 0xffff01ff); + + mb(); /* sync */ + isync(); +} +EXPORT_SYMBOL(switch_mmu_context); |