summaryrefslogtreecommitdiff
path: root/arch/powerpc/mm/tlb_32.c
blob: 6a69417cbc0ef3cf0eaba041081b2f3a53ae5f96 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
/*
 * 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
 *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
 *
 *  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 <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);
	}
}

/*
 * 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;
}