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