arch/sh/mm/tlbflush_64.c - kernel/msm-4.9 - Gitiles

 /*
  * arch/sh/mm/tlb-flush_64.c
  *
  * Copyright (C) 2000, 2001  Paolo Alberelli
  * Copyright (C) 2003  Richard Curnow (/proc/tlb, bug fixes)
  * Copyright (C) 2003 - 2009 Paul Mundt
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  */
 #include <linux/signal.h>
 #include <linux/rwsem.h>
 #include <linux/sched.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/string.h>
 #include <linux/types.h>
 #include <linux/ptrace.h>
 #include <linux/mman.h>
 #include <linux/mm.h>
 #include <linux/smp.h>
 #include <linux/perf_counter.h>
 #include <linux/interrupt.h>
 #include <asm/system.h>
 #include <asm/io.h>
 #include <asm/tlb.h>
 #include <asm/uaccess.h>
 #include <asm/pgalloc.h>
 #include <asm/mmu_context.h>

 extern void die(const char *,struct pt_regs *,long);

 #define PFLAG(val,flag)   (( (val) & (flag) ) ? #flag : "" )
 #define PPROT(flag) PFLAG(pgprot_val(prot),flag)

 static inline void print_prots(pgprot_t prot)
 {
 	printk("prot is 0x%08lx\n",pgprot_val(prot));

 	printk("%s %s %s %s %s\n",PPROT(_PAGE_SHARED),PPROT(_PAGE_READ),
 	       PPROT(_PAGE_EXECUTE),PPROT(_PAGE_WRITE),PPROT(_PAGE_USER));
 }

 static inline void print_vma(struct vm_area_struct *vma)
 {
 	printk("vma start 0x%08lx\n", vma->vm_start);
 	printk("vma end   0x%08lx\n", vma->vm_end);

 	print_prots(vma->vm_page_prot);
 	printk("vm_flags 0x%08lx\n", vma->vm_flags);
 }

 static inline void print_task(struct task_struct *tsk)
 {
 	printk("Task pid %d\n", task_pid_nr(tsk));
 }

 static pte_t *lookup_pte(struct mm_struct *mm, unsigned long address)
 {
 	pgd_t *dir;
 	pud_t *pud;
 	pmd_t *pmd;
 	pte_t *pte;
 	pte_t entry;

 	dir = pgd_offset(mm, address);
 	if (pgd_none(*dir))
 		return NULL;

 	pud = pud_offset(dir, address);
 	if (pud_none(*pud))
 		return NULL;

 	pmd = pmd_offset(pud, address);
 	if (pmd_none(*pmd))
 		return NULL;

 	pte = pte_offset_kernel(pmd, address);
 	entry = *pte;
 	if (pte_none(entry) || !pte_present(entry))
 		return NULL;

 	return pte;
 }

 /*
  * This routine handles page faults.  It determines the address,
  * and the problem, and then passes it off to one of the appropriate
  * routines.
  */
 asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
 			      unsigned long textaccess, unsigned long address)
 {
 	struct task_struct *tsk;
 	struct mm_struct *mm;
 	struct vm_area_struct * vma;
 	const struct exception_table_entry *fixup;
 	pte_t *pte;
 	int fault;

 	/* SIM
 	 * Note this is now called with interrupts still disabled
 	 * This is to cope with being called for a missing IO port
 	 * address with interrupts disabled. This should be fixed as
 	 * soon as we have a better 'fast path' miss handler.
 	 *
 	 * Plus take care how you try and debug this stuff.
 	 * For example, writing debug data to a port which you
 	 * have just faulted on is not going to work.
 	 */

 	tsk = current;
 	mm = tsk->mm;

 	/* Not an IO address, so reenable interrupts */
 	local_irq_enable();

 	perf_swcounter_event(PERF_COUNT_SW_PAGE_FAULTS, 1, 0, regs, address);

 	/*
 	 * If we're in an interrupt or have no user
 	 * context, we must not take the fault..
 	 */
 	if (in_atomic() || !mm)
 		goto no_context;

 	/* TLB misses upon some cache flushes get done under cli() */
 	down_read(&mm->mmap_sem);

 	vma = find_vma(mm, address);

 	if (!vma) {
 #ifdef DEBUG_FAULT
 		print_task(tsk);
 		printk("%s:%d fault, address is 0x%08x PC %016Lx textaccess %d writeaccess %d\n",
 		       __func__, __LINE__,
 		       address,regs->pc,textaccess,writeaccess);
 		show_regs(regs);
 #endif
 		goto bad_area;
 	}
 	if (vma->vm_start <= address) {
 		goto good_area;
 	}

 	if (!(vma->vm_flags & VM_GROWSDOWN)) {
 #ifdef DEBUG_FAULT
 		print_task(tsk);
 		printk("%s:%d fault, address is 0x%08x PC %016Lx textaccess %d writeaccess %d\n",
 		       __func__, __LINE__,
 		       address,regs->pc,textaccess,writeaccess);
 		show_regs(regs);

 		print_vma(vma);
 #endif
 		goto bad_area;
 	}
 	if (expand_stack(vma, address)) {
 #ifdef DEBUG_FAULT
 		print_task(tsk);
 		printk("%s:%d fault, address is 0x%08x PC %016Lx textaccess %d writeaccess %d\n",
 		       __func__, __LINE__,
 		       address,regs->pc,textaccess,writeaccess);
 		show_regs(regs);
 #endif
 		goto bad_area;
 	}
 /*
  * Ok, we have a good vm_area for this memory access, so
  * we can handle it..
  */
 good_area:
 	if (textaccess) {
 		if (!(vma->vm_flags & VM_EXEC))
 			goto bad_area;
 	} else {
 		if (writeaccess) {
 			if (!(vma->vm_flags & VM_WRITE))
 				goto bad_area;
 		} else {
 			if (!(vma->vm_flags & VM_READ))
 				goto bad_area;
 		}
 	}

 	/*
 	 * If for any reason at all we couldn't handle the fault,
 	 * make sure we exit gracefully rather than endlessly redo
 	 * the fault.
 	 */
 survive:
 	fault = handle_mm_fault(mm, vma, address, writeaccess ? FAULT_FLAG_WRITE : 0);
 	if (unlikely(fault & VM_FAULT_ERROR)) {
 		if (fault & VM_FAULT_OOM)
 			goto out_of_memory;
 		else if (fault & VM_FAULT_SIGBUS)
 			goto do_sigbus;
 		BUG();
 	}

 	if (fault & VM_FAULT_MAJOR) {
 		tsk->maj_flt++;
 		perf_swcounter_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, 0,
 				     regs, address);
 	} else {
 		tsk->min_flt++;
 		perf_swcounter_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, 0,
 				     regs, address);
 	}

 	/* If we get here, the page fault has been handled.  Do the TLB refill
 	   now from the newly-setup PTE, to avoid having to fault again right
 	   away on the same instruction. */
 	pte = lookup_pte (mm, address);
 	if (!pte) {
 		/* From empirical evidence, we can get here, due to
 		   !pte_present(pte).  (e.g. if a swap-in occurs, and the page
 		   is swapped back out again before the process that wanted it
 		   gets rescheduled?) */
 		goto no_pte;
 	}

 	__do_tlb_refill(address, textaccess, pte);

 no_pte:

 	up_read(&mm->mmap_sem);
 	return;

 /*
  * Something tried to access memory that isn't in our memory map..
  * Fix it, but check if it's kernel or user first..
  */
 bad_area:
 #ifdef DEBUG_FAULT
 	printk("fault:bad area\n");
 #endif
 	up_read(&mm->mmap_sem);

 	if (user_mode(regs)) {
 		static int count=0;
 		siginfo_t info;
 		if (count < 4) {
 			/* This is really to help debug faults when starting
 			 * usermode, so only need a few */
 			count++;
 			printk("user mode bad_area address=%08lx pid=%d (%s) pc=%08lx\n",
 				address, task_pid_nr(current), current->comm,
 				(unsigned long) regs->pc);
 #if 0
 			show_regs(regs);
 #endif
 		}
 		if (is_global_init(tsk)) {
 			panic("INIT had user mode bad_area\n");
 		}
 		tsk->thread.address = address;
 		tsk->thread.error_code = writeaccess;
 		info.si_signo = SIGSEGV;
 		info.si_errno = 0;
 		info.si_addr = (void *) address;
 		force_sig_info(SIGSEGV, &info, tsk);
 		return;
 	}

 no_context:
 #ifdef DEBUG_FAULT
 	printk("fault:No context\n");
 #endif
 	/* Are we prepared to handle this kernel fault?  */
 	fixup = search_exception_tables(regs->pc);
 	if (fixup) {
 		regs->pc = fixup->fixup;
 		return;
 	}

 /*
  * Oops. The kernel tried to access some bad page. We'll have to
  * terminate things with extreme prejudice.
  *
  */
 	if (address < PAGE_SIZE)
 		printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference");
 	else
 		printk(KERN_ALERT "Unable to handle kernel paging request");
 	printk(" at virtual address %08lx\n", address);
 	printk(KERN_ALERT "pc = %08Lx%08Lx\n", regs->pc >> 32, regs->pc & 0xffffffff);
 	die("Oops", regs, writeaccess);
 	do_exit(SIGKILL);

 /*
  * We ran out of memory, or some other thing happened to us that made
  * us unable to handle the page fault gracefully.
  */
 out_of_memory:
 	if (is_global_init(current)) {
 		panic("INIT out of memory\n");
 		yield();
 		goto survive;
 	}
 	printk("fault:Out of memory\n");
 	up_read(&mm->mmap_sem);
 	if (is_global_init(current)) {
 		yield();
 		down_read(&mm->mmap_sem);
 		goto survive;
 	}
 	printk("VM: killing process %s\n", tsk->comm);
 	if (user_mode(regs))
 		do_group_exit(SIGKILL);
 	goto no_context;

 do_sigbus:
 	printk("fault:Do sigbus\n");
 	up_read(&mm->mmap_sem);

 	/*
 	 * Send a sigbus, regardless of whether we were in kernel
 	 * or user mode.
 	 */
 	tsk->thread.address = address;
 	tsk->thread.error_code = writeaccess;
 	tsk->thread.trap_no = 14;
 	force_sig(SIGBUS, tsk);

 	/* Kernel mode? Handle exceptions or die */
 	if (!user_mode(regs))
 		goto no_context;
 }

 void update_mmu_cache(struct vm_area_struct * vma,
 			unsigned long address, pte_t pte)
 {
 	/*
 	 * This appears to get called once for every pte entry that gets
 	 * established => I don't think it's efficient to try refilling the
 	 * TLBs with the pages - some may not get accessed even.  Also, for
 	 * executable pages, it is impossible to determine reliably here which
 	 * TLB they should be mapped into (or both even).
 	 *
 	 * So, just do nothing here and handle faults on demand.  In the
 	 * TLBMISS handling case, the refill is now done anyway after the pte
 	 * has been fixed up, so that deals with most useful cases.
 	 */
 }

 void local_flush_tlb_one(unsigned long asid, unsigned long page)
 {
 	unsigned long long match, pteh=0, lpage;
 	unsigned long tlb;

 	/*
 	 * Sign-extend based on neff.
 	 */
 	lpage = (page & NEFF_SIGN) ? (page | NEFF_MASK) : page;
 	match = (asid << PTEH_ASID_SHIFT) | PTEH_VALID;
 	match |= lpage;

 	for_each_itlb_entry(tlb) {
 		asm volatile ("getcfg	%1, 0, %0"
 			      : "=r" (pteh)
 			      : "r" (tlb) );

 		if (pteh == match) {
 			__flush_tlb_slot(tlb);
 			break;
 		}
 	}

 	for_each_dtlb_entry(tlb) {
 		asm volatile ("getcfg	%1, 0, %0"
 			      : "=r" (pteh)
 			      : "r" (tlb) );

 		if (pteh == match) {
 			__flush_tlb_slot(tlb);
 			break;
 		}

 	}
 }

 void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
 {
 	unsigned long flags;

 	if (vma->vm_mm) {
 		page &= PAGE_MASK;
 		local_irq_save(flags);
 		local_flush_tlb_one(get_asid(), page);
 		local_irq_restore(flags);
 	}
 }

 void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
 			   unsigned long end)
 {
 	unsigned long flags;
 	unsigned long long match, pteh=0, pteh_epn, pteh_low;
 	unsigned long tlb;
 	unsigned int cpu = smp_processor_id();
 	struct mm_struct *mm;

 	mm = vma->vm_mm;
 	if (cpu_context(cpu, mm) == NO_CONTEXT)
 		return;

 	local_irq_save(flags);

 	start &= PAGE_MASK;
 	end &= PAGE_MASK;

 	match = (cpu_asid(cpu, mm) << PTEH_ASID_SHIFT) | PTEH_VALID;

 	/* Flush ITLB */
 	for_each_itlb_entry(tlb) {
 		asm volatile ("getcfg	%1, 0, %0"
 			      : "=r" (pteh)
 			      : "r" (tlb) );

 		pteh_epn = pteh & PAGE_MASK;
 		pteh_low = pteh & ~PAGE_MASK;

 		if (pteh_low == match && pteh_epn >= start && pteh_epn <= end)
 			__flush_tlb_slot(tlb);
 	}

 	/* Flush DTLB */
 	for_each_dtlb_entry(tlb) {
 		asm volatile ("getcfg	%1, 0, %0"
 			      : "=r" (pteh)
 			      : "r" (tlb) );

 		pteh_epn = pteh & PAGE_MASK;
 		pteh_low = pteh & ~PAGE_MASK;

 		if (pteh_low == match && pteh_epn >= start && pteh_epn <= end)
 			__flush_tlb_slot(tlb);
 	}

 	local_irq_restore(flags);
 }

 void local_flush_tlb_mm(struct mm_struct *mm)
 {
 	unsigned long flags;
 	unsigned int cpu = smp_processor_id();

 	if (cpu_context(cpu, mm) == NO_CONTEXT)
 		return;

 	local_irq_save(flags);

 	cpu_context(cpu, mm) = NO_CONTEXT;
 	if (mm == current->mm)
 		activate_context(mm, cpu);

 	local_irq_restore(flags);
 }

 void local_flush_tlb_all(void)
 {
 	/* Invalidate all, including shared pages, excluding fixed TLBs */
 	unsigned long flags, tlb;

 	local_irq_save(flags);

 	/* Flush each ITLB entry */
 	for_each_itlb_entry(tlb)
 		__flush_tlb_slot(tlb);

 	/* Flush each DTLB entry */
 	for_each_dtlb_entry(tlb)
 		__flush_tlb_slot(tlb);

 	local_irq_restore(flags);
 }

 void local_flush_tlb_kernel_range(unsigned long start, unsigned long end)
 {
         /* FIXME: Optimize this later.. */
         flush_tlb_all();
 }
	/*
	* arch/sh/mm/tlb-flush_64.c
	*
	* Copyright (C) 2000, 2001 Paolo Alberelli
	* Copyright (C) 2003 Richard Curnow (/proc/tlb, bug fixes)
	* Copyright (C) 2003 - 2009 Paul Mundt
	*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file "COPYING" in the main directory of this archive
	* for more details.
	*/
	#include <linux/signal.h>
	#include <linux/rwsem.h>
	#include <linux/sched.h>
	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/string.h>
	#include <linux/types.h>
	#include <linux/ptrace.h>
	#include <linux/mman.h>
	#include <linux/mm.h>
	#include <linux/smp.h>
	#include <linux/perf_counter.h>
	#include <linux/interrupt.h>
	#include <asm/system.h>
	#include <asm/io.h>
	#include <asm/tlb.h>
	#include <asm/uaccess.h>
	#include <asm/pgalloc.h>
	#include <asm/mmu_context.h>

	extern void die(const char ,struct pt_regs ,long);

	#define PFLAG(val,flag) (( (val) & (flag) ) ? #flag : "" )
	#define PPROT(flag) PFLAG(pgprot_val(prot),flag)

	static inline void print_prots(pgprot_t prot)
	{
	printk("prot is 0x%08lx\n",pgprot_val(prot));

	printk("%s %s %s %s %s\n",PPROT(_PAGE_SHARED),PPROT(_PAGE_READ),
	PPROT(_PAGE_EXECUTE),PPROT(_PAGE_WRITE),PPROT(_PAGE_USER));
	}

	static inline void print_vma(struct vm_area_struct *vma)
	{
	printk("vma start 0x%08lx\n", vma->vm_start);
	printk("vma end 0x%08lx\n", vma->vm_end);

	print_prots(vma->vm_page_prot);
	printk("vm_flags 0x%08lx\n", vma->vm_flags);
	}

	static inline void print_task(struct task_struct *tsk)
	{
	printk("Task pid %d\n", task_pid_nr(tsk));
	}

	static pte_t lookup_pte(struct mm_struct mm, unsigned long address)
	{
	pgd_t *dir;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;
	pte_t entry;

	dir = pgd_offset(mm, address);
	if (pgd_none(*dir))
	return NULL;

	pud = pud_offset(dir, address);
	if (pud_none(*pud))
	return NULL;

	pmd = pmd_offset(pud, address);
	if (pmd_none(*pmd))
	return NULL;

	pte = pte_offset_kernel(pmd, address);
	entry = *pte;
	if (pte_none(entry) \|\| !pte_present(entry))
	return NULL;

	return pte;
	}

	/*
	* This routine handles page faults. It determines the address,
	* and the problem, and then passes it off to one of the appropriate
	* routines.
	*/
	asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
	unsigned long textaccess, unsigned long address)
	{
	struct task_struct *tsk;
	struct mm_struct *mm;
	struct vm_area_struct * vma;
	const struct exception_table_entry *fixup;
	pte_t *pte;
	int fault;

	/* SIM
	* Note this is now called with interrupts still disabled
	* This is to cope with being called for a missing IO port
	* address with interrupts disabled. This should be fixed as
	* soon as we have a better 'fast path' miss handler.
	*
	* Plus take care how you try and debug this stuff.
	* For example, writing debug data to a port which you
	* have just faulted on is not going to work.
	*/

	tsk = current;
	mm = tsk->mm;

	/* Not an IO address, so reenable interrupts */
	local_irq_enable();

	perf_swcounter_event(PERF_COUNT_SW_PAGE_FAULTS, 1, 0, regs, address);

	/*
	* If we're in an interrupt or have no user
	* context, we must not take the fault..
	*/
	if (in_atomic() \|\| !mm)
	goto no_context;

	/* TLB misses upon some cache flushes get done under cli() */
	down_read(&mm->mmap_sem);

	vma = find_vma(mm, address);

	if (!vma) {
	#ifdef DEBUG_FAULT
	print_task(tsk);
	printk("%s:%d fault, address is 0x%08x PC %016Lx textaccess %d writeaccess %d\n",
	__func__, __LINE__,
	address,regs->pc,textaccess,writeaccess);
	show_regs(regs);
	#endif
	goto bad_area;
	}
	if (vma->vm_start <= address) {
	goto good_area;
	}

	if (!(vma->vm_flags & VM_GROWSDOWN)) {
	#ifdef DEBUG_FAULT
	print_task(tsk);
	printk("%s:%d fault, address is 0x%08x PC %016Lx textaccess %d writeaccess %d\n",
	__func__, __LINE__,
	address,regs->pc,textaccess,writeaccess);
	show_regs(regs);

	print_vma(vma);
	#endif
	goto bad_area;
	}
	if (expand_stack(vma, address)) {
	#ifdef DEBUG_FAULT
	print_task(tsk);
	printk("%s:%d fault, address is 0x%08x PC %016Lx textaccess %d writeaccess %d\n",
	__func__, __LINE__,
	address,regs->pc,textaccess,writeaccess);
	show_regs(regs);
	#endif
	goto bad_area;
	}
	/*
	* Ok, we have a good vm_area for this memory access, so
	* we can handle it..
	*/
	good_area:
	if (textaccess) {
	if (!(vma->vm_flags & VM_EXEC))
	goto bad_area;
	} else {
	if (writeaccess) {
	if (!(vma->vm_flags & VM_WRITE))
	goto bad_area;
	} else {
	if (!(vma->vm_flags & VM_READ))
	goto bad_area;
	}
	}

	/*
	* If for any reason at all we couldn't handle the fault,
	* make sure we exit gracefully rather than endlessly redo
	* the fault.
	*/
	survive:
	fault = handle_mm_fault(mm, vma, address, writeaccess ? FAULT_FLAG_WRITE : 0);
	if (unlikely(fault & VM_FAULT_ERROR)) {
	if (fault & VM_FAULT_OOM)
	goto out_of_memory;
	else if (fault & VM_FAULT_SIGBUS)
	goto do_sigbus;
	BUG();
	}

	if (fault & VM_FAULT_MAJOR) {
	tsk->maj_flt++;
	perf_swcounter_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, 0,
	regs, address);
	} else {
	tsk->min_flt++;
	perf_swcounter_event(PERF_COUNT_SW_PAGE_FAULTS_MIN, 1, 0,
	regs, address);
	}

	/* If we get here, the page fault has been handled. Do the TLB refill
	now from the newly-setup PTE, to avoid having to fault again right
	away on the same instruction. */
	pte = lookup_pte (mm, address);
	if (!pte) {
	/* From empirical evidence, we can get here, due to
	!pte_present(pte). (e.g. if a swap-in occurs, and the page
	is swapped back out again before the process that wanted it
	gets rescheduled?) */
	goto no_pte;
	}

	__do_tlb_refill(address, textaccess, pte);

	no_pte:

	up_read(&mm->mmap_sem);
	return;

	/*
	* Something tried to access memory that isn't in our memory map..
	* Fix it, but check if it's kernel or user first..
	*/
	bad_area:
	#ifdef DEBUG_FAULT
	printk("fault:bad area\n");
	#endif
	up_read(&mm->mmap_sem);

	if (user_mode(regs)) {
	static int count=0;
	siginfo_t info;
	if (count < 4) {
	/* This is really to help debug faults when starting
	* usermode, so only need a few */
	count++;
	printk("user mode bad_area address=%08lx pid=%d (%s) pc=%08lx\n",
	address, task_pid_nr(current), current->comm,
	(unsigned long) regs->pc);
	#if 0
	show_regs(regs);
	#endif
	}
	if (is_global_init(tsk)) {
	panic("INIT had user mode bad_area\n");
	}
	tsk->thread.address = address;
	tsk->thread.error_code = writeaccess;
	info.si_signo = SIGSEGV;
	info.si_errno = 0;
	info.si_addr = (void *) address;
	force_sig_info(SIGSEGV, &info, tsk);
	return;
	}

	no_context:
	#ifdef DEBUG_FAULT
	printk("fault:No context\n");
	#endif
	/* Are we prepared to handle this kernel fault? */
	fixup = search_exception_tables(regs->pc);
	if (fixup) {
	regs->pc = fixup->fixup;
	return;
	}

	/*
	* Oops. The kernel tried to access some bad page. We'll have to
	* terminate things with extreme prejudice.
	*
	*/
	if (address < PAGE_SIZE)
	printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference");
	else
	printk(KERN_ALERT "Unable to handle kernel paging request");
	printk(" at virtual address %08lx\n", address);
	printk(KERN_ALERT "pc = %08Lx%08Lx\n", regs->pc >> 32, regs->pc & 0xffffffff);
	die("Oops", regs, writeaccess);
	do_exit(SIGKILL);

	/*
	* We ran out of memory, or some other thing happened to us that made
	* us unable to handle the page fault gracefully.
	*/
	out_of_memory:
	if (is_global_init(current)) {
	panic("INIT out of memory\n");
	yield();
	goto survive;
	}
	printk("fault:Out of memory\n");
	up_read(&mm->mmap_sem);
	if (is_global_init(current)) {
	yield();
	down_read(&mm->mmap_sem);
	goto survive;
	}
	printk("VM: killing process %s\n", tsk->comm);
	if (user_mode(regs))
	do_group_exit(SIGKILL);
	goto no_context;

	do_sigbus:
	printk("fault:Do sigbus\n");
	up_read(&mm->mmap_sem);

	/*
	* Send a sigbus, regardless of whether we were in kernel
	* or user mode.
	*/
	tsk->thread.address = address;
	tsk->thread.error_code = writeaccess;
	tsk->thread.trap_no = 14;
	force_sig(SIGBUS, tsk);

	/* Kernel mode? Handle exceptions or die */
	if (!user_mode(regs))
	goto no_context;
	}

	void update_mmu_cache(struct vm_area_struct * vma,
	unsigned long address, pte_t pte)
	{
	/*
	* This appears to get called once for every pte entry that gets
	* established => I don't think it's efficient to try refilling the
	* TLBs with the pages - some may not get accessed even. Also, for
	* executable pages, it is impossible to determine reliably here which
	* TLB they should be mapped into (or both even).
	*
	* So, just do nothing here and handle faults on demand. In the
	* TLBMISS handling case, the refill is now done anyway after the pte
	* has been fixed up, so that deals with most useful cases.
	*/
	}

	void local_flush_tlb_one(unsigned long asid, unsigned long page)
	{
	unsigned long long match, pteh=0, lpage;
	unsigned long tlb;

	/*
	* Sign-extend based on neff.
	*/
	lpage = (page & NEFF_SIGN) ? (page \| NEFF_MASK) : page;
	match = (asid << PTEH_ASID_SHIFT) \| PTEH_VALID;
	match \|= lpage;

	for_each_itlb_entry(tlb) {
	asm volatile ("getcfg %1, 0, %0"
	: "=r" (pteh)
	: "r" (tlb) );

	if (pteh == match) {
	__flush_tlb_slot(tlb);
	break;
	}
	}

	for_each_dtlb_entry(tlb) {
	asm volatile ("getcfg %1, 0, %0"
	: "=r" (pteh)
	: "r" (tlb) );

	if (pteh == match) {
	__flush_tlb_slot(tlb);
	break;
	}

	}
	}

	void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
	{
	unsigned long flags;

	if (vma->vm_mm) {
	page &= PAGE_MASK;
	local_irq_save(flags);
	local_flush_tlb_one(get_asid(), page);
	local_irq_restore(flags);
	}
	}

	void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
	unsigned long end)
	{
	unsigned long flags;
	unsigned long long match, pteh=0, pteh_epn, pteh_low;
	unsigned long tlb;
	unsigned int cpu = smp_processor_id();
	struct mm_struct *mm;

	mm = vma->vm_mm;
	if (cpu_context(cpu, mm) == NO_CONTEXT)
	return;

	local_irq_save(flags);

	start &= PAGE_MASK;
	end &= PAGE_MASK;

	match = (cpu_asid(cpu, mm) << PTEH_ASID_SHIFT) \| PTEH_VALID;

	/* Flush ITLB */
	for_each_itlb_entry(tlb) {
	asm volatile ("getcfg %1, 0, %0"
	: "=r" (pteh)
	: "r" (tlb) );

	pteh_epn = pteh & PAGE_MASK;
	pteh_low = pteh & ~PAGE_MASK;

	if (pteh_low == match && pteh_epn >= start && pteh_epn <= end)
	__flush_tlb_slot(tlb);
	}

	/* Flush DTLB */
	for_each_dtlb_entry(tlb) {
	asm volatile ("getcfg %1, 0, %0"
	: "=r" (pteh)
	: "r" (tlb) );

	pteh_epn = pteh & PAGE_MASK;
	pteh_low = pteh & ~PAGE_MASK;

	if (pteh_low == match && pteh_epn >= start && pteh_epn <= end)
	__flush_tlb_slot(tlb);
	}

	local_irq_restore(flags);
	}

	void local_flush_tlb_mm(struct mm_struct *mm)
	{
	unsigned long flags;
	unsigned int cpu = smp_processor_id();

	if (cpu_context(cpu, mm) == NO_CONTEXT)
	return;

	local_irq_save(flags);

	cpu_context(cpu, mm) = NO_CONTEXT;
	if (mm == current->mm)
	activate_context(mm, cpu);

	local_irq_restore(flags);
	}

	void local_flush_tlb_all(void)
	{
	/* Invalidate all, including shared pages, excluding fixed TLBs */
	unsigned long flags, tlb;

	local_irq_save(flags);

	/* Flush each ITLB entry */
	for_each_itlb_entry(tlb)
	__flush_tlb_slot(tlb);

	/* Flush each DTLB entry */
	for_each_dtlb_entry(tlb)
	__flush_tlb_slot(tlb);

	local_irq_restore(flags);
	}

	void local_flush_tlb_kernel_range(unsigned long start, unsigned long end)
	{
	/* FIXME: Optimize this later.. */
	flush_tlb_all();
	}