kernel-ark/arch/x86/include/asm/tlbflush.h

#ifndef _ASM_X86_TLBFLUSH_H
#define _ASM_X86_TLBFLUSH_H

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

#include <asm/processor.h>
#include <asm/system.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)
{
	write_cr3(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 = read_cr4();
	/* clear PGE */
	write_cr4(cr4 & ~X86_CR4_PGE);
	/* write old PGE again and flush TLBs */
	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();
}

#ifdef CONFIG_X86_32
# define TLB_FLUSH_ALL	0xffffffff
#else
# define TLB_FLUSH_ALL	-1ULL
#endif

/*
 * 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, va) 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.
 *
 * x86-64 can only flush individual pages or full VMs. For a range flush
 * we always do the full VM. Might be worth trying if for a small
 * range a few INVLPGs in a row are a win.
 */

#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 native_flush_tlb_others(const struct cpumask *cpumask,
					   struct mm_struct *mm,
					   unsigned long va)
{
}

static inline void reset_lazy_tlbstate(void)
{
}

#else  /* SMP */

#include <asm/smp.h>

#define local_flush_tlb() __flush_tlb()

extern void flush_tlb_all(void);
extern void flush_tlb_current_task(void);
extern void flush_tlb_mm(struct mm_struct *);
extern void flush_tlb_page(struct vm_area_struct *, unsigned long);

#define flush_tlb()	flush_tlb_current_task()

static inline void flush_tlb_range(struct vm_area_struct *vma,
				   unsigned long start, unsigned long end)
{
	flush_tlb_mm(vma->vm_mm);
}

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

#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)
{
	percpu_write(cpu_tlbstate.state, 0);
	percpu_write(cpu_tlbstate.active_mm, &init_mm);
}

#endif	/* SMP */

#ifndef CONFIG_PARAVIRT
#define flush_tlb_others(mask, mm, va)	native_flush_tlb_others(mask, mm, va)
#endif

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

extern void zap_low_mappings(void);

#endif /* _ASM_X86_TLBFLUSH_H */