tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * linux/arch/h8300/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/m68knommu/mm/init.c
11 * linux/arch/m68k/mm/init.c
12 *
13 * Copyright (C) 1995 Hamish Macdonald
14 *
15 * JAN/1999 -- hacked to support ColdFire (gerg@snapgear.com)
16 * DEC/2000 -- linux 2.4 support <davidm@snapgear.com>
17 */
18
19#include <linux/signal.h>
20#include <linux/sched.h>
21#include <linux/kernel.h>
22#include <linux/errno.h>
23#include <linux/string.h>
24#include <linux/types.h>
25#include <linux/ptrace.h>
26#include <linux/mman.h>
27#include <linux/mm.h>
28#include <linux/swap.h>
29#include <linux/init.h>
30#include <linux/highmem.h>
31#include <linux/pagemap.h>
32#include <linux/bootmem.h>
33#include <linux/gfp.h>
34
35#include <asm/setup.h>
36#include <asm/segment.h>
37#include <asm/page.h>
38#include <asm/pgtable.h>
39#include <asm/sections.h>
40
41/*
42 * BAD_PAGE is the page that is used for page faults when linux
43 * is out-of-memory. Older versions of linux just did a
44 * do_exit(), but using this instead means there is less risk
45 * for a process dying in kernel mode, possibly leaving a inode
46 * unused etc..
47 *
48 * BAD_PAGETABLE is the accompanying page-table: it is initialized
49 * to point to BAD_PAGE entries.
50 *
51 * ZERO_PAGE is a special page that is used for zero-initialized
52 * data and COW.
53 */
54static unsigned long empty_bad_page_table;
55static unsigned long empty_bad_page;
56unsigned long empty_zero_page;
57
58/*
59 * paging_init() continues the virtual memory environment setup which
60 * was begun by the code in arch/head.S.
61 * The parameters are pointers to where to stick the starting and ending
62 * addresses of available kernel virtual memory.
63 */
64void __init paging_init(void)
65{
66 /*
67 * Make sure start_mem is page aligned, otherwise bootmem and
68 * page_alloc get different views og the world.
69 */
70 unsigned long start_mem = PAGE_ALIGN(memory_start);
71 unsigned long end_mem = memory_end & PAGE_MASK;
72
73 pr_debug("start_mem is %#lx\nvirtual_end is %#lx\n",
74 start_mem, end_mem);
75
76 /*
77 * Initialize the bad page table and bad page to point
78 * to a couple of allocated pages.
79 */
80 empty_bad_page_table = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
81 empty_bad_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
82 empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
83 memset((void *)empty_zero_page, 0, PAGE_SIZE);
84
85 /*
86 * Set up SFC/DFC registers (user data space).
87 */
88 set_fs(USER_DS);
89
90 pr_debug("before free_area_init\n");
91
92 pr_debug("free_area_init -> start_mem is %#lx\nvirtual_end is %#lx\n",
93 start_mem, end_mem);
94
95 {
96 unsigned long zones_size[MAX_NR_ZONES] = {0, };
97
98 zones_size[ZONE_NORMAL] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
99 free_area_init(zones_size);
100 }
101}
102
103void __init mem_init(void)
104{
105 pr_devel("Mem_init: start=%lx, end=%lx\n", memory_start, memory_end);
106
107 high_memory = (void *) (memory_end & PAGE_MASK);
108 max_mapnr = MAP_NR(high_memory);
109
110 /* this will put all low memory onto the freelists */
111 free_all_bootmem();
112
113 mem_init_print_info(NULL);
114}
115
116
117#ifdef CONFIG_BLK_DEV_INITRD
118void free_initrd_mem(unsigned long start, unsigned long end)
119{
120 free_reserved_area((void *)start, (void *)end, -1, "initrd");
121}
122#endif
123
124void
125free_initmem(void)
126{
127 free_initmem_default(-1);
128}