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 atomic_set(&mm->context.attach_count, 0);
20 mm->context.flush_mm = 0;
21 mm->context.asce_bits = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS;
23 mm->context.asce_bits |= _ASCE_TYPE_REGION3;
25 if (current->mm && current->mm->context.alloc_pgste) {
27 * alloc_pgste indicates, that any NEW context will be created
28 * with extended page tables. The old context is unchanged. The
29 * page table allocation and the page table operations will
30 * look at has_pgste to distinguish normal and extended page
31 * tables. The only way to create extended page tables is to
32 * set alloc_pgste and then create a new context (e.g. dup_mm).
33 * The page table allocation is called after init_new_context
34 * and if has_pgste is set, it will create extended page
37 mm->context.has_pgste = 1;
38 mm->context.alloc_pgste = 1;
40 mm->context.has_pgste = 0;
41 mm->context.alloc_pgste = 0;
43 mm->context.asce_limit = STACK_TOP_MAX;
44 crst_table_init((unsigned long *) mm->pgd, pgd_entry_type(mm));
48 #define destroy_context(mm) do { } while (0)
51 #define LCTL_OPCODE "lctl"
53 #define LCTL_OPCODE "lctlg"
56 static inline void update_mm(struct mm_struct *mm, struct task_struct *tsk)
60 S390_lowcore.user_asce = mm->context.asce_bits | __pa(pgd);
61 if (user_mode != HOME_SPACE_MODE) {
62 /* Load primary space page table origin. */
63 asm volatile(LCTL_OPCODE" 1,1,%0\n"
64 : : "m" (S390_lowcore.user_asce) );
66 /* Load home space page table origin. */
67 asm volatile(LCTL_OPCODE" 13,13,%0"
68 : : "m" (S390_lowcore.user_asce) );
69 set_fs(current->thread.mm_segment);
72 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
73 struct task_struct *tsk)
75 cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
77 atomic_dec(&prev->context.attach_count);
78 WARN_ON(atomic_read(&prev->context.attach_count) < 0);
79 atomic_inc(&next->context.attach_count);
80 /* Check for TLBs not flushed yet */
81 if (next->context.flush_mm)
85 #define enter_lazy_tlb(mm,tsk) do { } while (0)
86 #define deactivate_mm(tsk,mm) do { } while (0)
88 static inline void activate_mm(struct mm_struct *prev,
89 struct mm_struct *next)
91 switch_mm(prev, next, current);
94 static inline void arch_dup_mmap(struct mm_struct *oldmm,
98 if (oldmm->context.asce_limit < mm->context.asce_limit)
99 crst_table_downgrade(mm, oldmm->context.asce_limit);
103 static inline void arch_exit_mmap(struct mm_struct *mm)
107 #endif /* __S390_MMU_CONTEXT_H */