tlbflush.h

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#ifndef _ASM_X86_TLBFLUSH_H
#define _ASM_X86_TLBFLUSH_H

#include <linux/mm.h>
#include <linux/sched.h>

#include <asm/processor.h>
#include <asm/special_insns.h>

#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#else
#define __flush_tlb() __native_flush_tlb()
#define __flush_tlb_global() __native_flush_tlb_global()
#define __flush_tlb_single(addr) __native_flush_tlb_single(addr)
#endif

static inline void __native_flush_tlb(void)
{
    native_write_cr3(native_read_cr3());
}

static inline void __native_flush_tlb_global(void)
{
    unsigned long flags;
    unsigned long cr4;

    /*
     * Read-modify-write to CR4 - protect it from preemption and
     * from interrupts. (Use the raw variant because this code can
     * be called from deep inside debugging code.)
     */
    raw_local_irq_save(flags);

    cr4 = native_read_cr4();
    /* clear PGE */
    native_write_cr4(cr4 & ~X86_CR4_PGE);
    /* write old PGE again and flush TLBs */
    native_write_cr4(cr4);

    raw_local_irq_restore(flags);
}

static inline void __native_flush_tlb_single(unsigned long addr)
{
    asm volatile("invlpg (%0)" ::"r" (addr) : "memory");
}

static inline void __flush_tlb_all(void)
{
    if (cpu_has_pge)
        __flush_tlb_global();
    else
        __flush_tlb();
}

static inline void __flush_tlb_one(unsigned long addr)
{
    if (cpu_has_invlpg)
        __flush_tlb_single(addr);
    else
        __flush_tlb();
}

#define TLB_FLUSH_ALL   -1UL

/*
 * TLB flushing:
 *
 *  - flush_tlb() flushes the current mm struct TLBs
 *  - flush_tlb_all() flushes all processes TLBs
 *  - flush_tlb_mm(mm) flushes the specified mm context TLB's
 *  - flush_tlb_page(vma, vmaddr) flushes one page
 *  - flush_tlb_range(vma, start, end) flushes a range of pages
 *  - flush_tlb_kernel_range(start, end) flushes a range of kernel pages
 *  - flush_tlb_others(cpumask, mm, start, end) flushes TLBs on other cpus
 *
 * ..but the i386 has somewhat limited tlb flushing capabilities,
 * and page-granular flushes are available only on i486 and up.
 */

#ifndef CONFIG_SMP

#define flush_tlb() __flush_tlb()
#define flush_tlb_all() __flush_tlb_all()
#define local_flush_tlb() __flush_tlb()

static inline void flush_tlb_mm(struct mm_struct *mm)
{
    if (mm == current->active_mm)
        __flush_tlb();
}

static inline void flush_tlb_page(struct vm_area_struct *vma,
                  unsigned long addr)
{
    if (vma->vm_mm == current->active_mm)
        __flush_tlb_one(addr);
}

static inline void flush_tlb_range(struct vm_area_struct *vma,
                   unsigned long start, unsigned long end)
{
    if (vma->vm_mm == current->active_mm)
        __flush_tlb();
}

static inline void flush_tlb_mm_range(struct mm_struct *mm,
       unsigned long start, unsigned long end, unsigned long vmflag)
{
    if (mm == current->active_mm)
        __flush_tlb();
}

static inline void native_flush_tlb_others(const struct cpumask *cpumask,
                       struct mm_struct *mm,
                       unsigned long start,
                       unsigned long end)
{
}

static inline void reset_lazy_tlbstate(void)
{
}

static inline void flush_tlb_kernel_range(unsigned long start,
                      unsigned long end)
{
    flush_tlb_all();
}

#else  /* SMP */

#include <asm/smp.h>

#define local_flush_tlb() __flush_tlb()

#define flush_tlb_mm(mm)    flush_tlb_mm_range(mm, 0UL, TLB_FLUSH_ALL, 0UL)

#define flush_tlb_range(vma, start, end)    \
        flush_tlb_mm_range(vma->vm_mm, start, end, vma->vm_flags)

extern void flush_tlb_all(void);
extern void flush_tlb_current_task(void);
extern void flush_tlb_page(struct vm_area_struct *, unsigned long);
extern void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
                unsigned long end, unsigned long vmflag);
extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);

#define flush_tlb() flush_tlb_current_task()

void native_flush_tlb_others(const struct cpumask *cpumask,
                struct mm_struct *mm,
                unsigned long start, unsigned long end);

#define TLBSTATE_OK 1
#define TLBSTATE_LAZY   2

struct tlb_state {
    struct mm_struct *active_mm;
    int state;
};
DECLARE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate);

static inline void reset_lazy_tlbstate(void)
{
    this_cpu_write(cpu_tlbstate.state, 0);
    this_cpu_write(cpu_tlbstate.active_mm, &init_mm);
}

#endif  /* SMP */

#ifndef CONFIG_PARAVIRT
#define flush_tlb_others(mask, mm, start, end)  \
    native_flush_tlb_others(mask, mm, start, end)
#endif

#endif /* _ASM_X86_TLBFLUSH_H */