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-generic/mm_hooks.h>
16 static inline int init_new_context(struct task_struct *tsk,
19 mm->context.asce_bits = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS;
21 mm->context.asce_bits |= _ASCE_TYPE_REGION3;
23 if (current->mm->context.alloc_pgste) {
25 * alloc_pgste indicates, that any NEW context will be created
26 * with extended page tables. The old context is unchanged. The
27 * page table allocation and the page table operations will
28 * look at has_pgste to distinguish normal and extended page
29 * tables. The only way to create extended page tables is to
30 * set alloc_pgste and then create a new context (e.g. dup_mm).
31 * The page table allocation is called after init_new_context
32 * and if has_pgste is set, it will create extended page
35 mm->context.noexec = 0;
36 mm->context.has_pgste = 1;
37 mm->context.alloc_pgste = 1;
39 mm->context.noexec = s390_noexec;
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);
62 /* Load primary space page table origin. */
63 pgd = mm->context.noexec ? get_shadow_table(pgd) : pgd;
64 S390_lowcore.user_exec_asce = mm->context.asce_bits | __pa(pgd);
65 asm volatile(LCTL_OPCODE" 1,1,%0\n"
66 : : "m" (S390_lowcore.user_exec_asce) );
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);
74 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
75 struct task_struct *tsk)
77 cpu_set(smp_processor_id(), next->cpu_vm_mask);
81 #define enter_lazy_tlb(mm,tsk) do { } while (0)
82 #define deactivate_mm(tsk,mm) do { } while (0)
84 static inline void activate_mm(struct mm_struct *prev,
85 struct mm_struct *next)
87 switch_mm(prev, next, current);
90 #endif /* __S390_MMU_CONTEXT_H */