summaryrefslogtreecommitdiffstats
path: root/arch/um/kernel/tt/tlb.c
blob: 16fc6a28882d8b11dede6ecdec95fa73f7bee736 (plain)
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
/* 
 * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
 * Copyright 2003 PathScale, Inc.
 * Licensed under the GPL
 */

#include "linux/stddef.h"
#include "linux/kernel.h"
#include "linux/sched.h"
#include "linux/mm.h"
#include "asm/page.h"
#include "asm/pgtable.h"
#include "asm/uaccess.h"
#include "asm/tlbflush.h"
#include "user_util.h"
#include "mem_user.h"
#include "os.h"
#include "tlb.h"

static void *do_ops(union mm_context *mmu, struct host_vm_op *ops, int last,
		    int finished, void *flush)
{
	struct host_vm_op *op;
	int i;

	for(i = 0; i <= last; i++){
		op = &ops[i];
		switch(op->type){
		case MMAP:
                        os_map_memory((void *) op->u.mmap.addr, op->u.mmap.fd,
				      op->u.mmap.offset, op->u.mmap.len,
				      op->u.mmap.r, op->u.mmap.w,
				      op->u.mmap.x);
			break;
		case MUNMAP:
			os_unmap_memory((void *) op->u.munmap.addr,
					op->u.munmap.len);
			break;
		case MPROTECT:
			protect_memory(op->u.mprotect.addr, op->u.munmap.len,
				       op->u.mprotect.r, op->u.mprotect.w,
				       op->u.mprotect.x, 1);
			break;
		default:
			printk("Unknown op type %d in do_ops\n", op->type);
			break;
		}
	}

	return NULL;
}

static void fix_range(struct mm_struct *mm, unsigned long start_addr, 
		      unsigned long end_addr, int force)
{
        if((current->thread.mode.tt.extern_pid != -1) &&
           (current->thread.mode.tt.extern_pid != os_getpid()))
                panic("fix_range fixing wrong address space, current = 0x%p",
                      current);

        fix_range_common(mm, start_addr, end_addr, force, do_ops);
}

atomic_t vmchange_seq = ATOMIC_INIT(1);

void flush_tlb_kernel_range_tt(unsigned long start, unsigned long end)
{
        if(flush_tlb_kernel_range_common(start, end))
                atomic_inc(&vmchange_seq);
}

static void protect_vm_page(unsigned long addr, int w, int must_succeed)
{
	int err;

	err = protect_memory(addr, PAGE_SIZE, 1, w, 1, must_succeed);
	if(err == 0) return;
	else if((err == -EFAULT) || (err == -ENOMEM)){
		flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
		protect_vm_page(addr, w, 1);
	}
	else panic("protect_vm_page : protect failed, errno = %d\n", err);
}

void mprotect_kernel_vm(int w)
{
	struct mm_struct *mm;
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;
	unsigned long addr;
	
	mm = &init_mm;
	for(addr = start_vm; addr < end_vm;){
		pgd = pgd_offset(mm, addr);
		pud = pud_offset(pgd, addr);
		pmd = pmd_offset(pud, addr);
		if(pmd_present(*pmd)){
			pte = pte_offset_kernel(pmd, addr);
			if(pte_present(*pte)) protect_vm_page(addr, w, 0);
			addr += PAGE_SIZE;
		}
		else addr += PMD_SIZE;
	}
}

void flush_tlb_kernel_vm_tt(void)
{
        flush_tlb_kernel_range(start_vm, end_vm);
}

void __flush_tlb_one_tt(unsigned long addr)
{
        flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
}
  
void flush_tlb_range_tt(struct vm_area_struct *vma, unsigned long start, 
		     unsigned long end)
{
	if(vma->vm_mm != current->mm) return;

	/* Assumes that the range start ... end is entirely within
	 * either process memory or kernel vm
	 */
	if((start >= start_vm) && (start < end_vm)){
		if(flush_tlb_kernel_range_common(start, end))
			atomic_inc(&vmchange_seq);
	}
	else fix_range(vma->vm_mm, start, end, 0);
}

void flush_tlb_mm_tt(struct mm_struct *mm)
{
	unsigned long seq;

	if(mm != current->mm) return;

	fix_range(mm, 0, STACK_TOP, 0);

	seq = atomic_read(&vmchange_seq);
	if(current->thread.mode.tt.vm_seq == seq)
		return;
	current->thread.mode.tt.vm_seq = seq;
	flush_tlb_kernel_range_common(start_vm, end_vm);
}

void force_flush_all_tt(void)
{
	fix_range(current->mm, 0, STACK_TOP, 1);
	flush_tlb_kernel_range_common(start_vm, end_vm);
}