LXR linux/arch/powerpc/include/asm/mmu

   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 void mmu_context_init(void);
  18extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
  19extern void destroy_context(struct mm_struct *mm);
  20
  21extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next);
  22extern void switch_stab(struct task_struct *tsk, struct mm_struct *mm);
  23extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
  24extern void set_context(unsigned long id, pgd_t *pgd);
  25
  26/*
  27 * switch_mm is the entry point called from the architecture independent
  28 * code in kernel/sched.c
  29 */
  30static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
  31                             struct task_struct *tsk)
  32{
  33        /* Mark this context has been used on the new CPU */
  34        cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
  35
  36        /* 32-bit keeps track of the current PGDIR in the thread struct */
  37#ifdef CONFIG_PPC32
  38        tsk->thread.pgdir = next->pgd;
  39#endif /* CONFIG_PPC32 */
  40
  41        /* Nothing else to do if we aren't actually switching */
  42        if (prev == next)
  43                return;
  44
  45        /* We must stop all altivec streams before changing the HW
  46         * context
  47         */
  48#ifdef CONFIG_ALTIVEC
  49        if (cpu_has_feature(CPU_FTR_ALTIVEC))
  50                asm volatile ("dssall");
  51#endif /* CONFIG_ALTIVEC */
  52
  53        /* The actual HW switching method differs between the various
  54         * sub architectures.
  55         */
  56#ifdef CONFIG_PPC_STD_MMU_64
  57        if (cpu_has_feature(CPU_FTR_SLB))
  58                switch_slb(tsk, next);
  59        else
  60                switch_stab(tsk, next);
  61#else
  62        /* Out of line for now */
  63        switch_mmu_context(prev, next);
  64#endif
  65
  66}
  67
  68#define deactivate_mm(tsk,mm)   do { } while (0)
  69
  70/*
  71 * After we have set current->mm to a new value, this activates
  72 * the context for the new mm so we see the new mappings.
  73 */
  74static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
  75{
  76        unsigned long flags;
  77
  78        local_irq_save(flags);
  79        switch_mm(prev, next, current);
  80        local_irq_restore(flags);
  81}
  82
  83/* We don't currently use enter_lazy_tlb() for anything */
  84static inline void enter_lazy_tlb(struct mm_struct *mm,
  85                                  struct task_struct *tsk)
  86{
  87}
  88
  89#endif /* __KERNEL__ */
  90#endif /* __ASM_POWERPC_MMU_CONTEXT_H */
  91