blob: 22e2a0d02b81958ab078a874baa9d07c680142b2 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/arch/m68knommu/mm/init.c
3 *
4 * Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>,
5 * Kenneth Albanowski <kjahds@kjahds.com>,
6 * Copyright (C) 2000 Lineo, Inc. (www.lineo.com)
7 *
8 * Based on:
9 *
10 * linux/arch/m68k/mm/init.c
11 *
12 * Copyright (C) 1995 Hamish Macdonald
13 *
14 * JAN/1999 -- hacked to support ColdFire (gerg@snapgear.com)
15 * DEC/2000 -- linux 2.4 support <davidm@snapgear.com>
16 */
17
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include <linux/signal.h>
19#include <linux/sched.h>
20#include <linux/kernel.h>
21#include <linux/errno.h>
22#include <linux/string.h>
23#include <linux/types.h>
24#include <linux/ptrace.h>
25#include <linux/mman.h>
26#include <linux/mm.h>
27#include <linux/swap.h>
28#include <linux/init.h>
29#include <linux/highmem.h>
30#include <linux/pagemap.h>
31#include <linux/bootmem.h>
32#include <linux/slab.h>
33
34#include <asm/setup.h>
35#include <asm/segment.h>
36#include <asm/page.h>
37#include <asm/pgtable.h>
38#include <asm/system.h>
39#include <asm/machdep.h>
40
41#undef DEBUG
42
43extern void die_if_kernel(char *,struct pt_regs *,long);
44extern void free_initmem(void);
45
46/*
47 * BAD_PAGE is the page that is used for page faults when linux
48 * is out-of-memory. Older versions of linux just did a
49 * do_exit(), but using this instead means there is less risk
50 * for a process dying in kernel mode, possibly leaving a inode
51 * unused etc..
52 *
53 * BAD_PAGETABLE is the accompanying page-table: it is initialized
54 * to point to BAD_PAGE entries.
55 *
56 * ZERO_PAGE is a special page that is used for zero-initialized
57 * data and COW.
58 */
59static unsigned long empty_bad_page_table;
60
61static unsigned long empty_bad_page;
62
63unsigned long empty_zero_page;
64
Linus Torvalds1da177e2005-04-16 15:20:36 -070065void show_mem(void)
66{
67 unsigned long i;
68 int free = 0, total = 0, reserved = 0, shared = 0;
69 int cached = 0;
70
71 printk(KERN_INFO "\nMem-info:\n");
72 show_free_areas();
73 i = max_mapnr;
74 while (i-- > 0) {
75 total++;
76 if (PageReserved(mem_map+i))
77 reserved++;
78 else if (PageSwapCache(mem_map+i))
79 cached++;
80 else if (!page_count(mem_map+i))
81 free++;
82 else
83 shared += page_count(mem_map+i) - 1;
84 }
85 printk(KERN_INFO "%d pages of RAM\n",total);
86 printk(KERN_INFO "%d free pages\n",free);
87 printk(KERN_INFO "%d reserved pages\n",reserved);
88 printk(KERN_INFO "%d pages shared\n",shared);
89 printk(KERN_INFO "%d pages swap cached\n",cached);
90}
91
92extern unsigned long memory_start;
93extern unsigned long memory_end;
94
95/*
96 * paging_init() continues the virtual memory environment setup which
97 * was begun by the code in arch/head.S.
98 * The parameters are pointers to where to stick the starting and ending
99 * addresses of available kernel virtual memory.
100 */
Greg Ungererf386c3c2007-10-24 12:03:46 +1000101void __init paging_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102{
103 /*
104 * Make sure start_mem is page aligned, otherwise bootmem and
105 * page_alloc get different views of the world.
106 */
107#ifdef DEBUG
108 unsigned long start_mem = PAGE_ALIGN(memory_start);
109#endif
110 unsigned long end_mem = memory_end & PAGE_MASK;
111
112#ifdef DEBUG
113 printk (KERN_DEBUG "start_mem is %#lx\nvirtual_end is %#lx\n",
114 start_mem, end_mem);
115#endif
116
117 /*
118 * Initialize the bad page table and bad page to point
119 * to a couple of allocated pages.
120 */
121 empty_bad_page_table = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
122 empty_bad_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
123 empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
124 memset((void *)empty_zero_page, 0, PAGE_SIZE);
125
126 /*
127 * Set up SFC/DFC registers (user data space).
128 */
129 set_fs (USER_DS);
130
131#ifdef DEBUG
132 printk (KERN_DEBUG "before free_area_init\n");
133
134 printk (KERN_DEBUG "free_area_init -> start_mem is %#lx\nvirtual_end is %#lx\n",
135 start_mem, end_mem);
136#endif
137
138 {
Christoph Lameterf06a9682006-09-25 23:31:10 -0700139 unsigned long zones_size[MAX_NR_ZONES] = {0, };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140
141 zones_size[ZONE_DMA] = 0 >> PAGE_SHIFT;
142 zones_size[ZONE_NORMAL] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
143#ifdef CONFIG_HIGHMEM
144 zones_size[ZONE_HIGHMEM] = 0;
145#endif
146 free_area_init(zones_size);
147 }
148}
149
Greg Ungererf386c3c2007-10-24 12:03:46 +1000150void __init mem_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151{
152 int codek = 0, datak = 0, initk = 0;
153 unsigned long tmp;
154 extern char _etext, _stext, _sdata, _ebss, __init_begin, __init_end;
155 extern unsigned int _ramend, _rambase;
156 unsigned long len = _ramend - _rambase;
157 unsigned long start_mem = memory_start; /* DAVIDM - these must start at end of kernel */
158 unsigned long end_mem = memory_end; /* DAVIDM - this must not include kernel stack at top */
159
160#ifdef DEBUG
161 printk(KERN_DEBUG "Mem_init: start=%lx, end=%lx\n", start_mem, end_mem);
162#endif
163
164 end_mem &= PAGE_MASK;
165 high_memory = (void *) end_mem;
166
167 start_mem = PAGE_ALIGN(start_mem);
168 max_mapnr = num_physpages = (((unsigned long) high_memory) - PAGE_OFFSET) >> PAGE_SHIFT;
169
170 /* this will put all memory onto the freelists */
171 totalram_pages = free_all_bootmem();
172
173 codek = (&_etext - &_stext) >> 10;
174 datak = (&_ebss - &_sdata) >> 10;
175 initk = (&__init_begin - &__init_end) >> 10;
176
177 tmp = nr_free_pages() << PAGE_SHIFT;
Greg Ungerer2082b472006-06-26 10:33:10 +1000178 printk(KERN_INFO "Memory available: %luk/%luk RAM, (%dk kernel code, %dk data)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 tmp >> 10,
180 len >> 10,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 codek,
182 datak
183 );
184}
185
186
187#ifdef CONFIG_BLK_DEV_INITRD
188void free_initrd_mem(unsigned long start, unsigned long end)
189{
190 int pages = 0;
191 for (; start < end; start += PAGE_SIZE) {
192 ClearPageReserved(virt_to_page(start));
Nick Piggin7835e982006-03-22 00:08:40 -0800193 init_page_count(virt_to_page(start));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 free_page(start);
195 totalram_pages++;
196 pages++;
197 }
198 printk (KERN_NOTICE "Freeing initrd memory: %dk freed\n", pages);
199}
200#endif
201
202void
203free_initmem()
204{
205#ifdef CONFIG_RAMKERNEL
206 unsigned long addr;
207 extern char __init_begin, __init_end;
208 /*
209 * The following code should be cool even if these sections
210 * are not page aligned.
211 */
212 addr = PAGE_ALIGN((unsigned long)(&__init_begin));
213 /* next to check that the page we free is not a partial page */
214 for (; addr + PAGE_SIZE < (unsigned long)(&__init_end); addr +=PAGE_SIZE) {
215 ClearPageReserved(virt_to_page(addr));
Nick Piggin7835e982006-03-22 00:08:40 -0800216 init_page_count(virt_to_page(addr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 free_page(addr);
218 totalram_pages++;
219 }
220 printk(KERN_NOTICE "Freeing unused kernel memory: %ldk freed (0x%x - 0x%x)\n",
221 (addr - PAGE_ALIGN((long) &__init_begin)) >> 10,
222 (int)(PAGE_ALIGN((unsigned long)(&__init_begin))),
223 (int)(addr - PAGE_SIZE));
224#endif
225}
226