200 lines
5.3 KiB
C
200 lines
5.3 KiB
C
/*
|
|
* 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] = 0 >> PAGE_SHIFT;
|
|
zones_size[ZONE_NORMAL] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
|
|
#ifdef CONFIG_HIGHMEM
|
|
zones_size[ZONE_HIGHMEM] = 0;
|
|
#endif
|
|
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 */
|
|
|
|
#ifdef DEBUG
|
|
printk(KERN_DEBUG "Mem_init: start=%lx, end=%lx\n", start_mem, end_mem);
|
|
#endif
|
|
|
|
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
|
|
}
|
|
|