1#ifndef __ASM_POWERPC_MMU_CONTEXT_H
2#define __ASM_POWERPC_MMU_CONTEXT_H
3#ifdef __KERNEL__
4
5#include <linux/kernel.h>
6#include <linux/mm.h>
7#include <linux/sched.h>
8#include <linux/spinlock.h>
9#include <asm/mmu.h>
10#include <asm/cputable.h>
11#include <asm-generic/mm_hooks.h>
12#include <asm/cputhreads.h>
13
14/*
15 * Most if the context management is out of line
16 */
17extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
18extern void destroy_context(struct mm_struct *mm);
19
20extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next);
21extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
22extern void set_context(unsigned long id, pgd_t *pgd);
23
24#ifdef CONFIG_PPC_BOOK3S_64
25extern int __init_new_context(void);
26extern void __destroy_context(int context_id);
27static inline void mmu_context_init(void) { }
28#else
29extern unsigned long __init_new_context(void);
30extern void __destroy_context(unsigned long context_id);
31extern void mmu_context_init(void);
32#endif
33
34extern void switch_cop(struct mm_struct *next);
35extern int use_cop(unsigned long acop, struct mm_struct *mm);
36extern void drop_cop(unsigned long acop, struct mm_struct *mm);
37
38/*
39 * switch_mm is the entry point called from the architecture independent
40 * code in kernel/sched/core.c
41 */
42static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
43			     struct task_struct *tsk)
44{
45	/* Mark this context has been used on the new CPU */
46	cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
47
48	/* 32-bit keeps track of the current PGDIR in the thread struct */
49#ifdef CONFIG_PPC32
50	tsk->thread.pgdir = next->pgd;
51#endif /* CONFIG_PPC32 */
52
53	/* 64-bit Book3E keeps track of current PGD in the PACA */
54#ifdef CONFIG_PPC_BOOK3E_64
55	get_paca()->pgd = next->pgd;
56#endif
57	/* Nothing else to do if we aren't actually switching */
58	if (prev == next)
59		return;
60
61#ifdef CONFIG_PPC_ICSWX
62	/* Switch coprocessor context only if prev or next uses a coprocessor */
63	if (prev->context.acop || next->context.acop)
64		switch_cop(next);
65#endif /* CONFIG_PPC_ICSWX */
66
67	/* We must stop all altivec streams before changing the HW
68	 * context
69	 */
70#ifdef CONFIG_ALTIVEC
71	if (cpu_has_feature(CPU_FTR_ALTIVEC))
72		asm volatile ("dssall");
73#endif /* CONFIG_ALTIVEC */
74
75	/* The actual HW switching method differs between the various
76	 * sub architectures.
77	 */
78#ifdef CONFIG_PPC_STD_MMU_64
79	switch_slb(tsk, next);
80#else
81	/* Out of line for now */
82	switch_mmu_context(prev, next);
83#endif
84
85}
86
87#define deactivate_mm(tsk,mm)	do { } while (0)
88
89/*
90 * After we have set current->mm to a new value, this activates
91 * the context for the new mm so we see the new mappings.
92 */
93static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
94{
95	unsigned long flags;
96
97	local_irq_save(flags);
98	switch_mm(prev, next, current);
99	local_irq_restore(flags);
100}
101
102/* We don't currently use enter_lazy_tlb() for anything */
103static inline void enter_lazy_tlb(struct mm_struct *mm,
104				  struct task_struct *tsk)
105{
106	/* 64-bit Book3E keeps track of current PGD in the PACA */
107#ifdef CONFIG_PPC_BOOK3E_64
108	get_paca()->pgd = NULL;
109#endif
110}
111
112#endif /* __KERNEL__ */
113#endif /* __ASM_POWERPC_MMU_CONTEXT_H */
114