[mirror_ubuntu-zesty-kernel.git] / arch / s390 / include / asm / 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/tlbflush.h>
#include <asm/ctl_reg.h>

static inline int init_new_context(struct task_struct *tsk,
				   struct mm_struct *mm)
{
	cpumask_clear(&mm->context.cpu_attach_mask);
	atomic_set(&mm->context.attach_count, 0);
	mm->context.flush_mm = 0;
	mm->context.asce_bits = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS;
#ifdef CONFIG_64BIT
	mm->context.asce_bits |= _ASCE_TYPE_REGION3;
#endif
	mm->context.has_pgste = 0;
	mm->context.use_skey = 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)

static inline void set_user_asce(struct mm_struct *mm)
{
	S390_lowcore.user_asce = mm->context.asce_bits | __pa(mm->pgd);
	if (current->thread.mm_segment.ar4)
		__ctl_load(S390_lowcore.user_asce, 7, 7);
	set_cpu_flag(CIF_ASCE);
}

static inline void clear_user_asce(void)
{
	S390_lowcore.user_asce = S390_lowcore.kernel_asce;

	__ctl_load(S390_lowcore.user_asce, 1, 1);
	__ctl_load(S390_lowcore.user_asce, 7, 7);
}

static inline void load_kernel_asce(void)
{
	unsigned long asce;

	__ctl_store(asce, 1, 1);
	if (asce != S390_lowcore.kernel_asce)
		__ctl_load(S390_lowcore.kernel_asce, 1, 1);
	set_cpu_flag(CIF_ASCE);
}

static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
			     struct task_struct *tsk)
{
	int cpu = smp_processor_id();

	if (prev == next)
		return;
	if (MACHINE_HAS_TLB_LC)
		cpumask_set_cpu(cpu, &next->context.cpu_attach_mask);
	/* Clear old ASCE by loading the kernel ASCE. */
	__ctl_load(S390_lowcore.kernel_asce, 1, 1);
	__ctl_load(S390_lowcore.kernel_asce, 7, 7);
	atomic_inc(&next->context.attach_count);
	atomic_dec(&prev->context.attach_count);
	if (MACHINE_HAS_TLB_LC)
		cpumask_clear_cpu(cpu, &prev->context.cpu_attach_mask);
	S390_lowcore.user_asce = next->context.asce_bits | __pa(next->pgd);
}

#define finish_arch_post_lock_switch finish_arch_post_lock_switch
static inline void finish_arch_post_lock_switch(void)
{
	struct task_struct *tsk = current;
	struct mm_struct *mm = tsk->mm;

	load_kernel_asce();
	if (mm) {
		preempt_disable();
		while (atomic_read(&mm->context.attach_count) >> 16)
			cpu_relax();

		cpumask_set_cpu(smp_processor_id(), mm_cpumask(mm));
		if (mm->context.flush_mm)
			__tlb_flush_mm(mm);
		preempt_enable();
	}
	set_fs(current->thread.mm_segment);
}

#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);
	cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
	set_user_asce(next);
}

static inline void arch_dup_mmap(struct mm_struct *oldmm,
				 struct mm_struct *mm)
{
#ifdef CONFIG_64BIT
	if (oldmm->context.asce_limit < mm->context.asce_limit)
		crst_table_downgrade(mm, oldmm->context.asce_limit);
#endif
}

static inline void arch_exit_mmap(struct mm_struct *mm)
{
}

#endif /* __S390_MMU_CONTEXT_H */
Commit	Line	Data
1da177e4	1	/*
1da177e4 LT	2	* S390 version
	3	*
	4	* Derived from "include/asm-i386/mmu_context.h"
	5	*/
	6
	7	#ifndef __S390_MMU_CONTEXT_H
	8	#define __S390_MMU_CONTEXT_H
	9
c1821c2e	10	#include <asm/pgalloc.h>
146e4b3c	11	#include <asm/uaccess.h>
050eef36	12	#include <asm/tlbflush.h>
a0616cde	13	#include <asm/ctl_reg.h>
d6dd61c8	14
6f457e1a MS	15	static inline int init_new_context(struct task_struct *tsk,
	16	struct mm_struct *mm)
	17	{
1b948d6c	18	cpumask_clear(&mm->context.cpu_attach_mask);
050eef36 MS	19	atomic_set(&mm->context.attach_count, 0);
050eef36 MS	20	mm->context.flush_mm = 0;
146e4b3c	21	mm->context.asce_bits = _ASCE_TABLE_LENGTH \| _ASCE_USER_BITS;
6f457e1a	22	#ifdef CONFIG_64BIT
6252d702	23	mm->context.asce_bits \|= _ASCE_TYPE_REGION3;
6f457e1a	24	#endif
3eabaee9	25	mm->context.has_pgste = 0;
693ffc08	26	mm->context.use_skey = 0;
6252d702 MS	27	mm->context.asce_limit = STACK_TOP_MAX;
6252d702 MS	28	crst_table_init((unsigned long *) mm->pgd, pgd_entry_type(mm));
6f457e1a MS	29	return 0;
6f457e1a MS	30	}
1da177e4 LT	31
	32	#define destroy_context(mm) do { } while (0)
	33
beef560b	34	static inline void set_user_asce(struct mm_struct *mm)
1da177e4	35	{
f8b13505 MS	36	S390_lowcore.user_asce = mm->context.asce_bits \| __pa(mm->pgd);
	37	if (current->thread.mm_segment.ar4)
	38	__ctl_load(S390_lowcore.user_asce, 7, 7);
d3a73acb	39	set_cpu_flag(CIF_ASCE);
1da177e4 LT	40	}
1da177e4 LT	41
beef560b	42	static inline void clear_user_asce(void)
02a8f3ab MS	43	{
02a8f3ab MS	44	S390_lowcore.user_asce = S390_lowcore.kernel_asce;
457f2180	45
beef560b	46	__ctl_load(S390_lowcore.user_asce, 1, 1);
457f2180 HC	47	__ctl_load(S390_lowcore.user_asce, 7, 7);
	48	}
	49
beef560b	50	static inline void load_kernel_asce(void)
457f2180 HC	51	{
	52	unsigned long asce;
	53
	54	__ctl_store(asce, 1, 1);
	55	if (asce != S390_lowcore.kernel_asce)
	56	__ctl_load(S390_lowcore.kernel_asce, 1, 1);
d3a73acb	57	set_cpu_flag(CIF_ASCE);
02a8f3ab MS	58	}
02a8f3ab MS	59
1da177e4	60	static inline void switch_mm(struct mm_struct prev, struct mm_struct next,
c1821c2e	61	struct task_struct *tsk)
1da177e4	62	{
53e857f3 MS	63	int cpu = smp_processor_id();
	64
	65	if (prev == next)
	66	return;
1b948d6c MS	67	if (MACHINE_HAS_TLB_LC)
1b948d6c MS	68	cpumask_set_cpu(cpu, &next->context.cpu_attach_mask);
beef560b MS	69	/* Clear old ASCE by loading the kernel ASCE. */
	70	__ctl_load(S390_lowcore.kernel_asce, 1, 1);
	71	__ctl_load(S390_lowcore.kernel_asce, 7, 7);
beef560b	72	atomic_inc(&next->context.attach_count);
050eef36	73	atomic_dec(&prev->context.attach_count);
1b948d6c MS	74	if (MACHINE_HAS_TLB_LC)
1b948d6c MS	75	cpumask_clear_cpu(cpu, &prev->context.cpu_attach_mask);
f8b13505	76	S390_lowcore.user_asce = next->context.asce_bits \| __pa(next->pgd);
53e857f3 MS	77	}
	78
	79	#define finish_arch_post_lock_switch finish_arch_post_lock_switch
	80	static inline void finish_arch_post_lock_switch(void)
	81	{
	82	struct task_struct *tsk = current;
	83	struct mm_struct *mm = tsk->mm;
	84
f8b13505 MS	85	load_kernel_asce();
	86	if (mm) {
	87	preempt_disable();
	88	while (atomic_read(&mm->context.attach_count) >> 16)
	89	cpu_relax();
	90
	91	cpumask_set_cpu(smp_processor_id(), mm_cpumask(mm));
	92	if (mm->context.flush_mm)
	93	__tlb_flush_mm(mm);
	94	preempt_enable();
	95	}
	96	set_fs(current->thread.mm_segment);
1da177e4 LT	97	}
1da177e4 LT	98
3610cce8	99	#define enter_lazy_tlb(mm,tsk) do { } while (0)
1da177e4 LT	100	#define deactivate_mm(tsk,mm) do { } while (0)
1da177e4 LT	101
4448aaf0	102	static inline void activate_mm(struct mm_struct *prev,
1da177e4 LT	103	struct mm_struct *next)
1da177e4 LT	104	{
beef560b MS	105	switch_mm(prev, next, current);
	106	cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
	107	set_user_asce(next);
1da177e4 LT	108	}
1da177e4 LT	109
0f6f281b MS	110	static inline void arch_dup_mmap(struct mm_struct *oldmm,
	111	struct mm_struct *mm)
	112	{
	113	#ifdef CONFIG_64BIT
	114	if (oldmm->context.asce_limit < mm->context.asce_limit)
	115	crst_table_downgrade(mm, oldmm->context.asce_limit);
	116	#endif
	117	}
	118
	119	static inline void arch_exit_mmap(struct mm_struct *mm)
	120	{
	121	}
	122
c1821c2e	123	#endif /* __S390_MMU_CONTEXT_H */