1/* 2 * include/asm-s390/mmu_context.h 3 * 4 * S390 version 5 * 6 * Derived from "include/asm-i386/mmu_context.h" 7 */ 8 9#ifndef __S390_MMU_CONTEXT_H 10#define __S390_MMU_CONTEXT_H 11 12#include <asm/pgalloc.h> 13#include <asm/uaccess.h> 14#include <asm/tlbflush.h> 15#include <asm-generic/mm_hooks.h> 16 17static inline int init_new_context(struct task_struct *tsk, 18 struct mm_struct *mm) 19{ 20 atomic_set(&mm->context.attach_count, 0); 21 mm->context.flush_mm = 0; 22 mm->context.asce_bits = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS; 23#ifdef CONFIG_64BIT 24 mm->context.asce_bits |= _ASCE_TYPE_REGION3; 25#endif 26 if (current->mm->context.alloc_pgste) { 27 /* 28 * alloc_pgste indicates, that any NEW context will be created 29 * with extended page tables. The old context is unchanged. The 30 * page table allocation and the page table operations will 31 * look at has_pgste to distinguish normal and extended page 32 * tables. The only way to create extended page tables is to 33 * set alloc_pgste and then create a new context (e.g. dup_mm). 34 * The page table allocation is called after init_new_context 35 * and if has_pgste is set, it will create extended page 36 * tables. 37 */ 38 mm->context.noexec = 0; 39 mm->context.has_pgste = 1; 40 mm->context.alloc_pgste = 1; 41 } else { 42 mm->context.noexec = (user_mode == SECONDARY_SPACE_MODE); 43 mm->context.has_pgste = 0; 44 mm->context.alloc_pgste = 0; 45 } 46 mm->context.asce_limit = STACK_TOP_MAX; 47 crst_table_init((unsigned long *) mm->pgd, pgd_entry_type(mm)); 48 return 0; 49} 50 51#define destroy_context(mm) do { } while (0) 52 53#ifndef __s390x__ 54#define LCTL_OPCODE "lctl" 55#else 56#define LCTL_OPCODE "lctlg" 57#endif 58 59static inline void update_mm(struct mm_struct *mm, struct task_struct *tsk) 60{ 61 pgd_t *pgd = mm->pgd; 62 63 S390_lowcore.user_asce = mm->context.asce_bits | __pa(pgd); 64 if (user_mode != HOME_SPACE_MODE) { 65 /* Load primary space page table origin. */ 66 pgd = mm->context.noexec ? get_shadow_table(pgd) : pgd; 67 S390_lowcore.user_exec_asce = mm->context.asce_bits | __pa(pgd); 68 asm volatile(LCTL_OPCODE" 1,1,%0\n" 69 : : "m" (S390_lowcore.user_exec_asce) ); 70 } else 71 /* Load home space page table origin. */ 72 asm volatile(LCTL_OPCODE" 13,13,%0" 73 : : "m" (S390_lowcore.user_asce) ); 74 set_fs(current->thread.mm_segment); 75} 76 77static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, 78 struct task_struct *tsk) 79{ 80 cpumask_set_cpu(smp_processor_id(), mm_cpumask(next)); 81 update_mm(next, tsk); 82 atomic_dec(&prev->context.attach_count); 83 WARN_ON(atomic_read(&prev->context.attach_count) < 0); 84 atomic_inc(&next->context.attach_count); 85 /* Check for TLBs not flushed yet */ 86 if (next->context.flush_mm) 87 __tlb_flush_mm(next); 88} 89 90#define enter_lazy_tlb(mm,tsk) do { } while (0) 91#define deactivate_mm(tsk,mm) do { } while (0) 92 93static inline void activate_mm(struct mm_struct *prev, 94 struct mm_struct *next) 95{ 96 switch_mm(prev, next, current); 97} 98 99#endif /* __S390_MMU_CONTEXT_H */ 100