| /* |
| * 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 <linux/uaccess.h> |
| #include <linux/mm_types.h> |
| #include <asm/tlbflush.h> |
| #include <asm/ctl_reg.h> |
| |
| static inline int init_new_context(struct task_struct *tsk, |
| struct mm_struct *mm) |
| { |
| spin_lock_init(&mm->context.pgtable_lock); |
| INIT_LIST_HEAD(&mm->context.pgtable_list); |
| spin_lock_init(&mm->context.gmap_lock); |
| INIT_LIST_HEAD(&mm->context.gmap_list); |
| cpumask_clear(&mm->context.cpu_attach_mask); |
| atomic_set(&mm->context.flush_count, 0); |
| mm->context.gmap_asce = 0; |
| mm->context.flush_mm = 0; |
| #ifdef CONFIG_PGSTE |
| mm->context.alloc_pgste = page_table_allocate_pgste; |
| mm->context.has_pgste = 0; |
| mm->context.use_skey = 0; |
| mm->context.use_cmma = 0; |
| #endif |
| switch (mm->context.asce_limit) { |
| case 1UL << 42: |
| /* |
| * forked 3-level task, fall through to set new asce with new |
| * mm->pgd |
| */ |
| case 0: |
| /* context created by exec, set asce limit to 4TB */ |
| mm->context.asce_limit = STACK_TOP_MAX; |
| mm->context.asce = __pa(mm->pgd) | _ASCE_TABLE_LENGTH | |
| _ASCE_USER_BITS | _ASCE_TYPE_REGION3; |
| break; |
| case 1UL << 53: |
| /* forked 4-level task, set new asce with new mm->pgd */ |
| mm->context.asce = __pa(mm->pgd) | _ASCE_TABLE_LENGTH | |
| _ASCE_USER_BITS | _ASCE_TYPE_REGION2; |
| break; |
| case 1UL << 31: |
| /* forked 2-level compat task, set new asce with new mm->pgd */ |
| mm->context.asce = __pa(mm->pgd) | _ASCE_TABLE_LENGTH | |
| _ASCE_USER_BITS | _ASCE_TYPE_SEGMENT; |
| /* pgd_alloc() did not increase mm->nr_pmds */ |
| mm_inc_nr_pmds(mm); |
| } |
| crst_table_init((unsigned long *) mm->pgd, pgd_entry_type(mm)); |
| return 0; |
| } |
| |
| #define destroy_context(mm) do { } while (0) |
| |
| static inline void set_user_asce(struct mm_struct *mm) |
| { |
| S390_lowcore.user_asce = mm->context.asce; |
| if (current->thread.mm_segment.ar4) |
| __ctl_load(S390_lowcore.user_asce, 7, 7); |
| set_cpu_flag(CIF_ASCE_PRIMARY); |
| } |
| |
| static inline void clear_user_asce(void) |
| { |
| S390_lowcore.user_asce = S390_lowcore.kernel_asce; |
| |
| __ctl_load(S390_lowcore.user_asce, 1, 1); |
| __ctl_load(S390_lowcore.user_asce, 7, 7); |
| } |
| |
| static inline void load_kernel_asce(void) |
| { |
| unsigned long asce; |
| |
| __ctl_store(asce, 1, 1); |
| if (asce != S390_lowcore.kernel_asce) |
| __ctl_load(S390_lowcore.kernel_asce, 1, 1); |
| set_cpu_flag(CIF_ASCE_PRIMARY); |
| } |
| |
| static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, |
| struct task_struct *tsk) |
| { |
| int cpu = smp_processor_id(); |
| |
| S390_lowcore.user_asce = next->context.asce; |
| if (prev == next) |
| return; |
| cpumask_set_cpu(cpu, &next->context.cpu_attach_mask); |
| cpumask_set_cpu(cpu, mm_cpumask(next)); |
| /* Clear old ASCE by loading the kernel ASCE. */ |
| __ctl_load(S390_lowcore.kernel_asce, 1, 1); |
| __ctl_load(S390_lowcore.kernel_asce, 7, 7); |
| cpumask_clear_cpu(cpu, &prev->context.cpu_attach_mask); |
| } |
| |
| #define finish_arch_post_lock_switch finish_arch_post_lock_switch |
| static inline void finish_arch_post_lock_switch(void) |
| { |
| struct task_struct *tsk = current; |
| struct mm_struct *mm = tsk->mm; |
| |
| load_kernel_asce(); |
| if (mm) { |
| preempt_disable(); |
| while (atomic_read(&mm->context.flush_count)) |
| cpu_relax(); |
| |
| if (mm->context.flush_mm) |
| __tlb_flush_mm(mm); |
| preempt_enable(); |
| } |
| set_fs(current->thread.mm_segment); |
| } |
| |
| #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); |
| set_user_asce(next); |
| } |
| |
| static inline void arch_dup_mmap(struct mm_struct *oldmm, |
| struct mm_struct *mm) |
| { |
| } |
| |
| static inline void arch_exit_mmap(struct mm_struct *mm) |
| { |
| } |
| |
| static inline void arch_unmap(struct mm_struct *mm, |
| struct vm_area_struct *vma, |
| unsigned long start, unsigned long end) |
| { |
| } |
| |
| static inline void arch_bprm_mm_init(struct mm_struct *mm, |
| struct vm_area_struct *vma) |
| { |
| } |
| |
| static inline bool arch_vma_access_permitted(struct vm_area_struct *vma, |
| bool write, bool execute, bool foreign) |
| { |
| /* by default, allow everything */ |
| return true; |
| } |
| #endif /* __S390_MMU_CONTEXT_H */ |