| /* |
| * S390 version |
| * |
| * Derived from "include/asm-i386/mmu_context.h" |
| */ |
| |
| #ifndef __S390_MMU_CONTEXT_H |
| #define __S390_MMU_CONTEXT_H |
| |
| #include <asm/pgalloc.h> |
| #include <asm/uaccess.h> |
| #include <asm/tlbflush.h> |
| #include <asm/ctl_reg.h> |
| |
| static inline int init_new_context(struct task_struct *tsk, |
| struct mm_struct *mm) |
| { |
| atomic_set(&mm->context.attach_count, 0); |
| mm->context.flush_mm = 0; |
| mm->context.asce_bits = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS; |
| #ifdef CONFIG_64BIT |
| mm->context.asce_bits |= _ASCE_TYPE_REGION3; |
| #endif |
| if (current->mm && current->mm->context.alloc_pgste) { |
| /* |
| * alloc_pgste indicates, that any NEW context will be created |
| * with extended page tables. The old context is unchanged. The |
| * page table allocation and the page table operations will |
| * look at has_pgste to distinguish normal and extended page |
| * tables. The only way to create extended page tables is to |
| * set alloc_pgste and then create a new context (e.g. dup_mm). |
| * The page table allocation is called after init_new_context |
| * and if has_pgste is set, it will create extended page |
| * tables. |
| */ |
| mm->context.has_pgste = 1; |
| mm->context.alloc_pgste = 1; |
| } else { |
| mm->context.has_pgste = 0; |
| mm->context.alloc_pgste = 0; |
| } |
| mm->context.asce_limit = STACK_TOP_MAX; |
| crst_table_init((unsigned long *) mm->pgd, pgd_entry_type(mm)); |
| return 0; |
| } |
| |
| #define destroy_context(mm) do { } while (0) |
| |
| #ifndef CONFIG_64BIT |
| #define LCTL_OPCODE "lctl" |
| #else |
| #define LCTL_OPCODE "lctlg" |
| #endif |
| |
| static inline void update_mm(struct mm_struct *mm, struct task_struct *tsk) |
| { |
| pgd_t *pgd = mm->pgd; |
| |
| S390_lowcore.user_asce = mm->context.asce_bits | __pa(pgd); |
| if (addressing_mode != HOME_SPACE_MODE) { |
| /* Load primary space page table origin. */ |
| asm volatile(LCTL_OPCODE" 1,1,%0\n" |
| : : "m" (S390_lowcore.user_asce) ); |
| } else |
| /* Load home space page table origin. */ |
| asm volatile(LCTL_OPCODE" 13,13,%0" |
| : : "m" (S390_lowcore.user_asce) ); |
| set_fs(current->thread.mm_segment); |
| } |
| |
| static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, |
| struct task_struct *tsk) |
| { |
| cpumask_set_cpu(smp_processor_id(), mm_cpumask(next)); |
| update_mm(next, tsk); |
| atomic_dec(&prev->context.attach_count); |
| WARN_ON(atomic_read(&prev->context.attach_count) < 0); |
| atomic_inc(&next->context.attach_count); |
| /* Check for TLBs not flushed yet */ |
| if (next->context.flush_mm) |
| __tlb_flush_mm(next); |
| } |
| |
| #define enter_lazy_tlb(mm,tsk) do { } while (0) |
| #define deactivate_mm(tsk,mm) do { } while (0) |
| |
| static inline void activate_mm(struct mm_struct *prev, |
| struct mm_struct *next) |
| { |
| switch_mm(prev, next, current); |
| } |
| |
| static inline void arch_dup_mmap(struct mm_struct *oldmm, |
| struct mm_struct *mm) |
| { |
| #ifdef CONFIG_64BIT |
| if (oldmm->context.asce_limit < mm->context.asce_limit) |
| crst_table_downgrade(mm, oldmm->context.asce_limit); |
| #endif |
| } |
| |
| static inline void arch_exit_mmap(struct mm_struct *mm) |
| { |
| } |
| |
| #endif /* __S390_MMU_CONTEXT_H */ |