2 * This file contains the routines for TLB flushing.
3 * On machines where the MMU uses a hash table to store virtual to
4 * physical translations, these routines flush entries from the
8 * Derived from arch/ppc/mm/init.c:
9 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
11 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
12 * and Cort Dougan (PReP) (cort@cs.nmt.edu)
13 * Copyright (C) 1996 Paul Mackerras
14 * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
16 * Derived from "arch/i386/mm/init.c"
17 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
19 * This program is free software; you can redistribute it and/or
20 * modify it under the terms of the GNU General Public License
21 * as published by the Free Software Foundation; either version
22 * 2 of the License, or (at your option) any later version.
26 #include <linux/kernel.h>
28 #include <linux/init.h>
29 #include <linux/highmem.h>
30 #include <asm/tlbflush.h>
36 * Called when unmapping pages to flush entries from the TLB/hash table.
38 void flush_hash_entry(struct mm_struct *mm, pte_t *ptep, unsigned long addr)
40 unsigned long ptephys;
43 ptephys = __pa(ptep) & PAGE_MASK;
44 flush_hash_pages(mm->context.id, addr, ptephys, 1);
49 * Called by ptep_set_access_flags, must flush on CPUs for which the
50 * DSI handler can't just "fixup" the TLB on a write fault
52 void flush_tlb_page_nohash(struct vm_area_struct *vma, unsigned long addr)
60 * Called at the end of a mmu_gather operation to make sure the
61 * TLB flush is completely done.
63 void tlb_flush(struct mmu_gather *tlb)
67 * 603 needs to flush the whole TLB here since
68 * it doesn't use a hash table.
77 * - flush_tlb_mm(mm) flushes the specified mm context TLB's
78 * - flush_tlb_page(vma, vmaddr) flushes one page
79 * - flush_tlb_range(vma, start, end) flushes a range of pages
80 * - flush_tlb_kernel_range(start, end) flushes kernel pages
82 * since the hardware hash table functions as an extension of the
83 * tlb as far as the linux tables are concerned, flush it too.
88 * 750 SMP is a Bad Idea because the 750 doesn't broadcast all
89 * the cache operations on the bus. Hence we need to use an IPI
90 * to get the other CPU(s) to invalidate their TLBs.
93 #define FINISH_FLUSH smp_send_tlb_invalidate(0)
95 #define FINISH_FLUSH do { } while (0)
98 static void flush_range(struct mm_struct *mm, unsigned long start,
102 unsigned long pmd_end;
104 unsigned int ctx = mm->context.id;
113 end = (end - 1) | ~PAGE_MASK;
114 pmd = pmd_offset(pgd_offset(mm, start), start);
116 pmd_end = ((start + PGDIR_SIZE) & PGDIR_MASK) - 1;
119 if (!pmd_none(*pmd)) {
120 count = ((pmd_end - start) >> PAGE_SHIFT) + 1;
121 flush_hash_pages(ctx, start, pmd_val(*pmd), count);
131 * Flush kernel TLB entries in the given range
133 void flush_tlb_kernel_range(unsigned long start, unsigned long end)
135 flush_range(&init_mm, start, end);
140 * Flush all the (user) entries for the address space described by mm.
142 void flush_tlb_mm(struct mm_struct *mm)
144 struct vm_area_struct *mp;
152 * It is safe to go down the mm's list of vmas when called
153 * from dup_mmap, holding mmap_sem. It would also be safe from
154 * unmap_region or exit_mmap, but not from vmtruncate on SMP -
155 * but it seems dup_mmap is the only SMP case which gets here.
157 for (mp = mm->mmap; mp != NULL; mp = mp->vm_next)
158 flush_range(mp->vm_mm, mp->vm_start, mp->vm_end);
162 void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr)
164 struct mm_struct *mm;
171 mm = (vmaddr < TASK_SIZE)? vma->vm_mm: &init_mm;
172 pmd = pmd_offset(pgd_offset(mm, vmaddr), vmaddr);
174 flush_hash_pages(mm->context.id, vmaddr, pmd_val(*pmd), 1);
179 * For each address in the range, find the pte for the address
180 * and check _PAGE_HASHPTE bit; if it is set, find and destroy
181 * the corresponding HPTE.
183 void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
186 flush_range(vma->vm_mm, start, end);