/*
* include/asm-s390/mmu_context.h
*
* S390 version
*
* Derived from "include/asm-i386/mmu_context.h"
*/
#ifndef __S390_MMU_CONTEXT_H
#define __S390_MMU_CONTEXT_H
#include <asm/pgalloc.h>
#include <asm/uaccess.h>
#include <asm-generic/mm_hooks.h>
static inline int init_new_context(struct task_struct *tsk,
struct mm_struct *mm)
{
mm->context.asce_bits = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS;
#ifdef CONFIG_64BIT
mm->context.asce_bits |= _ASCE_TYPE_REGION3;
#endif
if (current->mm->context.alloc_pgste) {
/*
* alloc_pgste indicates, that any NEW context will be created
* with extended page tables. The old context is unchanged. The
* page table allocation and the page table operations will
* look at has_pgste to distinguish normal and extended page
* tables. The only way to create extended page tables is to
* set alloc_pgste and then create a new context (e.g. dup_mm).
* The page table allocation is called after init_new_context
* and if has_pgste is set, it will create extended page
* tables.
*/
mm->context.noexec = 0;
mm->context.has_pgste = 1;
mm->context.alloc_pgste = 1;
} else {
mm->context.noexec = s390_noexec;
mm->context.has_pgste = 0;
mm->context.alloc_pgste = 0;
}
mm->context.asce_limit = STACK_TOP_MAX;
crst_table_init((unsigned long *) mm->pgd, pgd_entry_type(mm));
return 0;
}
#define destroy_context(mm) do { } while (0)
#ifndef __s390x__
#define LCTL_OPCODE "lctl"
#else
#define LCTL_OPCODE "lctlg"
#endif
static inline void update_mm(struct mm_struct *mm, struct task_struct *tsk)
{
pgd_t *pgd = mm->pgd;
S390_lowcore.user_asce = mm->context.asce_bits | __pa(pgd);
if (switch_amode) {
/* Load primary space page table origin. */
pgd = mm->context.noexec ? get_shadow_table(pgd) : pgd;
S390_lowcore.user_exec_asce = mm->context.asce_bits | __pa(pgd);
asm volatile(LCTL_OPCODE" 1,1,%0\n"
: : "m" (S390_lowcore.user_exec_asce) );
} else
/* Load home space page table origin. */
asm volatile(LCTL_OPCODE" 13,13,%0"
: : "m" (S390_lowcore.user_asce) );
set_fs(current->thread.mm_segment);
}
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
struct task_struct *tsk)
{
cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
update_mm(next, tsk);
}
#define enter_lazy_tlb(mm,tsk) do { } while (0)
#define deactivate_mm(tsk,mm) do { } while (0)
static inline void activate_mm(struct mm_struct *prev,
struct mm_struct *next)
{
switch_mm(prev, next, current);
}
#endif /* __S390_MMU_CONTEXT_H */
