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
189
190
191
192
193
|
/*
* linux/arch/m68knommu/mm/init.c
*
* Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>,
* Kenneth Albanowski <kjahds@kjahds.com>,
* Copyright (C) 2000 Lineo, Inc. (www.lineo.com)
*
* Based on:
*
* linux/arch/m68k/mm/init.c
*
* Copyright (C) 1995 Hamish Macdonald
*
* JAN/1999 -- hacked to support ColdFire (gerg@snapgear.com)
* DEC/2000 -- linux 2.4 support <davidm@snapgear.com>
*/
#include <linux/signal.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/swap.h>
#include <linux/init.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/bootmem.h>
#include <linux/slab.h>
#include <asm/setup.h>
#include <asm/segment.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/machdep.h>
#undef DEBUG
extern void die_if_kernel(char *,struct pt_regs *,long);
extern void free_initmem(void);
/*
* BAD_PAGE is the page that is used for page faults when linux
* is out-of-memory. Older versions of linux just did a
* do_exit(), but using this instead means there is less risk
* for a process dying in kernel mode, possibly leaving a inode
* unused etc..
*
* BAD_PAGETABLE is the accompanying page-table: it is initialized
* to point to BAD_PAGE entries.
*
* ZERO_PAGE is a special page that is used for zero-initialized
* data and COW.
*/
static unsigned long empty_bad_page_table;
static unsigned long empty_bad_page;
unsigned long empty_zero_page;
extern unsigned long memory_start;
extern unsigned long memory_end;
/*
* paging_init() continues the virtual memory environment setup which
* was begun by the code in arch/head.S.
* The parameters are pointers to where to stick the starting and ending
* addresses of available kernel virtual memory.
*/
void __init paging_init(void)
{
/*
* Make sure start_mem is page aligned, otherwise bootmem and
* page_alloc get different views of the world.
*/
#ifdef DEBUG
unsigned long start_mem = PAGE_ALIGN(memory_start);
#endif
unsigned long end_mem = memory_end & PAGE_MASK;
#ifdef DEBUG
printk (KERN_DEBUG "start_mem is %#lx\nvirtual_end is %#lx\n",
start_mem, end_mem);
#endif
/*
* Initialize the bad page table and bad page to point
* to a couple of allocated pages.
*/
empty_bad_page_table = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
empty_bad_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
memset((void *)empty_zero_page, 0, PAGE_SIZE);
/*
* Set up SFC/DFC registers (user data space).
*/
set_fs (USER_DS);
#ifdef DEBUG
printk (KERN_DEBUG "before free_area_init\n");
printk (KERN_DEBUG "free_area_init -> start_mem is %#lx\nvirtual_end is %#lx\n",
start_mem, end_mem);
#endif
{
unsigned long zones_size[MAX_NR_ZONES] = {0, };
zones_size[ZONE_DMA] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
free_area_init(zones_size);
}
}
void __init mem_init(void)
{
int codek = 0, datak = 0, initk = 0;
unsigned long tmp;
extern char _etext, _stext, _sdata, _ebss, __init_begin, __init_end;
extern unsigned int _ramend, _rambase;
unsigned long len = _ramend - _rambase;
unsigned long start_mem = memory_start; /* DAVIDM - these must start at end of kernel */
unsigned long end_mem = memory_end; /* DAVIDM - this must not include kernel stack at top */
pr_debug("Mem_init: start=%lx, end=%lx\n", start_mem, end_mem);
end_mem &= PAGE_MASK;
high_memory = (void *) end_mem;
start_mem = PAGE_ALIGN(start_mem);
max_mapnr = num_physpages = (((unsigned long) high_memory) - PAGE_OFFSET) >> PAGE_SHIFT;
/* this will put all memory onto the freelists */
totalram_pages = free_all_bootmem();
codek = (&_etext - &_stext) >> 10;
datak = (&_ebss - &_sdata) >> 10;
initk = (&__init_begin - &__init_end) >> 10;
tmp = nr_free_pages() << PAGE_SHIFT;
printk(KERN_INFO "Memory available: %luk/%luk RAM, (%dk kernel code, %dk data)\n",
tmp >> 10,
len >> 10,
codek,
datak
);
}
#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
int pages = 0;
for (; start < end; start += PAGE_SIZE) {
ClearPageReserved(virt_to_page(start));
init_page_count(virt_to_page(start));
free_page(start);
totalram_pages++;
pages++;
}
printk (KERN_NOTICE "Freeing initrd memory: %dk freed\n", pages);
}
#endif
void
free_initmem()
{
#ifdef CONFIG_RAMKERNEL
unsigned long addr;
extern char __init_begin, __init_end;
/*
* The following code should be cool even if these sections
* are not page aligned.
*/
addr = PAGE_ALIGN((unsigned long)(&__init_begin));
/* next to check that the page we free is not a partial page */
for (; addr + PAGE_SIZE < (unsigned long)(&__init_end); addr +=PAGE_SIZE) {
ClearPageReserved(virt_to_page(addr));
init_page_count(virt_to_page(addr));
free_page(addr);
totalram_pages++;
}
printk(KERN_NOTICE "Freeing unused kernel memory: %ldk freed (0x%x - 0x%x)\n",
(addr - PAGE_ALIGN((long) &__init_begin)) >> 10,
(int)(PAGE_ALIGN((unsigned long)(&__init_begin))),
(int)(addr - PAGE_SIZE));
#endif
}
|
