159 строки
4.5 KiB
C
159 строки
4.5 KiB
C
/* init.c: memory initialisation for FRV
|
|
*
|
|
* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*
|
|
* Derived from:
|
|
* - 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)
|
|
* - linux/arch/m68k/mm/init.c
|
|
* - Copyright (C) 1995 Hamish Macdonald
|
|
*/
|
|
|
|
#include <linux/signal.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/sched/task.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/gfp.h>
|
|
#include <linux/swap.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/string.h>
|
|
#include <linux/types.h>
|
|
#include <linux/bootmem.h>
|
|
#include <linux/highmem.h>
|
|
#include <linux/module.h>
|
|
|
|
#include <asm/setup.h>
|
|
#include <asm/segment.h>
|
|
#include <asm/page.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/mmu_context.h>
|
|
#include <asm/virtconvert.h>
|
|
#include <asm/sections.h>
|
|
#include <asm/tlb.h>
|
|
|
|
#undef DEBUG
|
|
|
|
/*
|
|
* 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;
|
|
EXPORT_SYMBOL(empty_zero_page);
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* 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)
|
|
{
|
|
unsigned long zones_size[MAX_NR_ZONES] = {0, };
|
|
|
|
/* allocate some pages for kernel housekeeping tasks */
|
|
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);
|
|
|
|
#ifdef CONFIG_HIGHMEM
|
|
if (get_num_physpages() - num_mappedpages) {
|
|
pgd_t *pge;
|
|
pud_t *pue;
|
|
pmd_t *pme;
|
|
|
|
pkmap_page_table = alloc_bootmem_pages(PAGE_SIZE);
|
|
|
|
pge = swapper_pg_dir + pgd_index_k(PKMAP_BASE);
|
|
pue = pud_offset(pge, PKMAP_BASE);
|
|
pme = pmd_offset(pue, PKMAP_BASE);
|
|
__set_pmd(pme, virt_to_phys(pkmap_page_table) | _PAGE_TABLE);
|
|
}
|
|
#endif
|
|
|
|
/* distribute the allocatable pages across the various zones and pass them to the allocator
|
|
*/
|
|
zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn;
|
|
#ifdef CONFIG_HIGHMEM
|
|
zones_size[ZONE_HIGHMEM] = get_num_physpages() - num_mappedpages;
|
|
#endif
|
|
|
|
free_area_init(zones_size);
|
|
|
|
#ifdef CONFIG_MMU
|
|
/* initialise init's MMU context */
|
|
init_new_context(&init_task, &init_mm);
|
|
#endif
|
|
|
|
} /* end paging_init() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
*
|
|
*/
|
|
void __init mem_init(void)
|
|
{
|
|
unsigned long code_size = _etext - _stext;
|
|
|
|
/* this will put all low memory onto the freelists */
|
|
free_all_bootmem();
|
|
#if defined(CONFIG_MMU) && defined(CONFIG_HIGHMEM)
|
|
{
|
|
unsigned long pfn;
|
|
|
|
for (pfn = get_num_physpages() - 1;
|
|
pfn >= num_mappedpages; pfn--)
|
|
free_highmem_page(&mem_map[pfn]);
|
|
}
|
|
#endif
|
|
|
|
mem_init_print_info(NULL);
|
|
if (rom_length > 0 && rom_length >= code_size)
|
|
printk("Memory available: %luKiB/%luKiB ROM\n",
|
|
(rom_length - code_size) >> 10, rom_length >> 10);
|
|
} /* end mem_init() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* free the memory that was only required for initialisation
|
|
*/
|
|
void free_initmem(void)
|
|
{
|
|
#if defined(CONFIG_RAMKERNEL) && !defined(CONFIG_PROTECT_KERNEL)
|
|
free_initmem_default(-1);
|
|
#endif
|
|
} /* end free_initmem() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* free the initial ramdisk memory
|
|
*/
|
|
#ifdef CONFIG_BLK_DEV_INITRD
|
|
void __init free_initrd_mem(unsigned long start, unsigned long end)
|
|
{
|
|
free_reserved_area((void *)start, (void *)end, -1, "initrd");
|
|
} /* end free_initrd_mem() */
|
|
#endif
|