2 * include/asm-s390/mmu_context.h
6 * Derived from "include/asm-i386/mmu_context.h"
9 #ifndef __S390_MMU_CONTEXT_H
10 #define __S390_MMU_CONTEXT_H
12 #include <asm/pgalloc.h>
13 #include <asm/uaccess.h>
14 #include <asm/tlbflush.h>
16 static inline int init_new_context(struct task_struct *tsk,
19 spin_lock_init(&mm->context.list_lock);
20 INIT_LIST_HEAD(&mm->context.pgtable_list);
21 INIT_LIST_HEAD(&mm->context.gmap_list);
22 atomic_set(&mm->context.attach_count, 0);
23 mm->context.flush_mm = 0;
24 if (current->mm && current->mm->context.alloc_pgste) {
26 * alloc_pgste indicates, that any NEW context will be created
27 * with extended page tables. The old context is unchanged. The
28 * page table allocation and the page table operations will
29 * look at has_pgste to distinguish normal and extended page
30 * tables. The only way to create extended page tables is to
31 * set alloc_pgste and then create a new context (e.g. dup_mm).
32 * The page table allocation is called after init_new_context
33 * and if has_pgste is set, it will create extended page
36 mm->context.has_pgste = 1;
37 mm->context.alloc_pgste = 1;
39 mm->context.has_pgste = 0;
40 mm->context.alloc_pgste = 0;
42 if (mm->context.asce_limit == 0) {
43 /* context created by exec, set asce limit to 4TB */
44 mm->context.asce_bits = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS;
46 mm->context.asce_bits |= _ASCE_TYPE_REGION3;
48 mm->context.asce_limit = STACK_TOP_MAX;
50 crst_table_init((unsigned long *) mm->pgd, pgd_entry_type(mm));
54 #define destroy_context(mm) do { } while (0)
57 #define LCTL_OPCODE "lctl"
59 #define LCTL_OPCODE "lctlg"
62 static inline void update_mm(struct mm_struct *mm, struct task_struct *tsk)
66 S390_lowcore.user_asce = mm->context.asce_bits | __pa(pgd);
67 if (user_mode != HOME_SPACE_MODE) {
68 /* Load primary space page table origin. */
69 asm volatile(LCTL_OPCODE" 1,1,%0\n"
70 : : "m" (S390_lowcore.user_asce) );
72 /* Load home space page table origin. */
73 asm volatile(LCTL_OPCODE" 13,13,%0"
74 : : "m" (S390_lowcore.user_asce) );
75 set_fs(current->thread.mm_segment);
78 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
79 struct task_struct *tsk)
81 cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
83 atomic_dec(&prev->context.attach_count);
84 WARN_ON(atomic_read(&prev->context.attach_count) < 0);
85 atomic_inc(&next->context.attach_count);
86 /* Check for TLBs not flushed yet */
87 if (next->context.flush_mm)
91 #define enter_lazy_tlb(mm,tsk) do { } while (0)
92 #define deactivate_mm(tsk,mm) do { } while (0)
94 static inline void activate_mm(struct mm_struct *prev,
95 struct mm_struct *next)
97 switch_mm(prev, next, current);
100 static inline void arch_dup_mmap(struct mm_struct *oldmm,
101 struct mm_struct *mm)
105 static inline void arch_exit_mmap(struct mm_struct *mm)
109 #endif /* __S390_MMU_CONTEXT_H */