/*
* This file contains the routines for TLB flushing.
* On machines where the MMU uses a hash table to store virtual to
* physical translations, these routines flush entries from the
* hash table also.
* -- paulus
*
* Derived from arch/ppc/mm/init.c:
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
*
* Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
* and Cort Dougan (PReP) (cort@cs.nmt.edu)
* Copyright (C) 1996 Paul Mackerras
*
* Derived from "arch/i386/mm/init.c"
* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <asm/tlbflush.h>
#include <asm/tlb.h>
#include "mmu_decl.h"
/*
* Called when unmapping pages to flush entries from the TLB/hash table.
*/
void flush_hash_entry(struct mm_struct *mm, pte_t *ptep, unsigned long addr)
{
unsigned long ptephys;
if (Hash != 0) {
ptephys = __pa(ptep) & PAGE_MASK;
flush_hash_pages(mm->context.id, addr, ptephys, 1);
}
}
EXPORT_SYMBOL(flush_hash_entry);
/*
* Called by ptep_set_access_flags, must flush on CPUs for which the
* DSI handler can't just "fixup" the TLB on a write fault
*/
void flush_tlb_page_nohash(struct vm_area_struct *vma, unsigned long addr)
{
if (Hash != 0)
return;
_tlbie(addr);
}
/*
* Called at the end of a mmu_gather operation to make sure the
* TLB flush is completely done.
*/
void tlb_flush(struct mmu_gather *tlb)
{
if (Hash == 0) {
/*
* 603 needs to flush the whole TLB here since
* it doesn't use a hash table.
*/
_tlbia();
}
}
/*
* TLB flushing:
*
* - 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 kernel pages
*
* since the hardware hash table functions as an extension of the
* tlb as far as the linux tables are concerned, flush it too.
* -- Cort
*/
/*
* 750 SMP is a Bad Idea because the 750 doesn't broadcast all
* the cache operations on the bus. Hence we need to use an IPI
* to get the other CPU(s) to invalidate their TLBs.
*/
#ifdef CONFIG_SMP_750
#define FINISH_FLUSH smp_send_tlb_invalidate(0)
#else
#define FINISH_FLUSH do { } while (0)
#endif
static void flush_range(struct mm_struct *mm, unsigned long start,
unsigned long end)
{
pmd_t *pmd;
unsigned long pmd_end;
int count;
unsigned int ctx = mm->context.id;
if (Hash == 0) {
_tlbia();
return;
}
start &= PAGE_MASK;
if (start >= end)
return;
end = (end - 1) | ~PAGE_MASK;
pmd = pmd_offset(pud_offset(pgd_offset(mm, start), start), start);
for (;;) {
pmd_end = ((start + PGDIR_SIZE) & PGDIR_MASK) - 1;
if (pmd_end > end)
pmd_end = end;
if (!pmd_none(*pmd)) {
count = ((pmd_end - start) >> PAGE_SHIFT) + 1;
flush_hash_pages(ctx, start, pmd_val(*pmd), count);
}
if (pmd_end == end)
break;
start = pmd_end + 1;
++pmd;
}
}
/*
* Flush kernel TLB entries in the given range
*/
void flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
flush_range(&init_mm, start, end);
FINISH_FLUSH;
}
/*
* Flush all the (user) entries for the address space described by mm.
*/
void flush_tlb_mm(struct mm_struct *mm)
{
struct vm_area_struct *mp;
if (Hash == 0) {
_tlbia();
return;
}
/*
* It is safe to go down the mm's list of vmas when called
* from dup_mmap, holding mmap_sem. It would also be safe from
* unmap_region or exit_mmap, but not from vmtruncate on SMP -
* but it seems dup_mmap is the only SMP case which gets here.
*/
for (mp = mm->mmap; mp != NULL; mp = mp->vm_next)
flush_range(mp->vm_mm, mp->vm_start, mp->vm_end);
FINISH_FLUSH;
}
void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
{
struct mm_struct *mm;
pmd_t *pmd;
if (Hash == 0) {
_tlbie(vmaddr);
return;
}
mm = (vmaddr < TASK_SIZE)? vma->vm_mm: &init_mm;
pmd = pmd_offset(pud_offset(pgd_offset(mm, vmaddr), vmaddr), vmaddr);
if (!pmd_none(*pmd))
flush_hash_pages(mm->context.id, vmaddr, pmd_val(*pmd), 1);
FINISH_FLUSH;
}
/*
* For each address in the range, find the pte for the address
* and check _PAGE_HASHPTE bit; if it is set, find and destroy
* the corresponding HPTE.
*/
void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
unsigned long end)
{
flush_range(vma->vm_mm, start, end);
FINISH_FLUSH;
}
