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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* arch/sh64/mm/init.c
*
* Copyright (C) 2000, 2001 Paolo Alberelli
* Copyright (C) 2003, 2004 Paul Mundt
*
*/
#include <linux/init.h>
#include <linux/rwsem.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/bootmem.h>
#include <asm/mmu_context.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/tlb.h>
#ifdef CONFIG_BLK_DEV_INITRD
#include <linux/blk.h>
#endif
DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
/*
* Cache of MMU context last used.
*/
unsigned long mmu_context_cache;
pgd_t * mmu_pdtp_cache;
int after_bootmem = 0;
/*
* 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 an 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.
*/
extern unsigned char empty_zero_page[PAGE_SIZE];
extern unsigned char empty_bad_page[PAGE_SIZE];
extern pte_t empty_bad_pte_table[PTRS_PER_PTE];
extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
extern char _text, _etext, _edata, __bss_start, _end;
extern char __init_begin, __init_end;
/* It'd be good if these lines were in the standard header file. */
#define START_PFN (NODE_DATA(0)->bdata->node_boot_start >> PAGE_SHIFT)
#define MAX_LOW_PFN (NODE_DATA(0)->bdata->node_low_pfn)
void show_mem(void)
{
int i, total = 0, reserved = 0;
int shared = 0, cached = 0;
printk("Mem-info:\n");
show_free_areas();
printk("Free swap: %6ldkB\n",nr_swap_pages<<(PAGE_SHIFT-10));
i = max_mapnr;
while (i-- > 0) {
total++;
if (PageReserved(mem_map+i))
reserved++;
else if (PageSwapCache(mem_map+i))
cached++;
else if (page_count(mem_map+i))
shared += page_count(mem_map+i) - 1;
}
printk("%d pages of RAM\n",total);
printk("%d reserved pages\n",reserved);
printk("%d pages shared\n",shared);
printk("%d pages swap cached\n",cached);
printk("%ld pages in page table cache\n",pgtable_cache_size);
}
/*
* paging_init() sets up the page tables.
*
* head.S already did a lot to set up address translation for the kernel.
* Here we comes with:
* . MMU enabled
* . ASID set (SR)
* . some 512MB regions being mapped of which the most relevant here is:
* . CACHED segment (ASID 0 [irrelevant], shared AND NOT user)
* . possible variable length regions being mapped as:
* . UNCACHED segment (ASID 0 [irrelevant], shared AND NOT user)
* . All of the memory regions are placed, independently from the platform
* on high addresses, above 0x80000000.
* . swapper_pg_dir is already cleared out by the .space directive
* in any case swapper does not require a real page directory since
* it's all kernel contained.
*
* Those pesky NULL-reference errors in the kernel are then
* dealt with by not mapping address 0x00000000 at all.
*
*/
void __init paging_init(void)
{
unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0};
pgd_init((unsigned long)swapper_pg_dir);
pgd_init((unsigned long)swapper_pg_dir +
sizeof(pgd_t) * USER_PTRS_PER_PGD);
mmu_context_cache = MMU_CONTEXT_FIRST_VERSION;
/*
* All memory is good as ZONE_NORMAL (fall-through) and ZONE_DMA.
*/
zones_size[ZONE_DMA] = MAX_LOW_PFN - START_PFN;
NODE_DATA(0)->node_mem_map = NULL;
free_area_init_node(0, NODE_DATA(0), zones_size, __MEMORY_START >> PAGE_SHIFT, 0);
}
void __init mem_init(void)
{
int codesize, reservedpages, datasize, initsize;
int tmp;
max_mapnr = num_physpages = MAX_LOW_PFN - START_PFN;
high_memory = (void *)__va(MAX_LOW_PFN * PAGE_SIZE);
/*
* Clear the zero-page.
* This is not required but we might want to re-use
* this very page to pass boot parameters, one day.
*/
memset(empty_zero_page, 0, PAGE_SIZE);
/* this will put all low memory onto the freelists */
totalram_pages += free_all_bootmem_node(NODE_DATA(0));
reservedpages = 0;
for (tmp = 0; tmp < num_physpages; tmp++)
/*
* Only count reserved RAM pages
*/
if (PageReserved(mem_map+tmp))
reservedpages++;
after_bootmem = 1;
codesize = (unsigned long) &_etext - (unsigned long) &_text;
datasize = (unsigned long) &_edata - (unsigned long) &_etext;
initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
printk("Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init)\n",
(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
max_mapnr << (PAGE_SHIFT-10),
codesize >> 10,
reservedpages << (PAGE_SHIFT-10),
datasize >> 10,
initsize >> 10);
}
void free_initmem(void)
{
unsigned long addr;
addr = (unsigned long)(&__init_begin);
for (; addr < (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 ("Freeing unused kernel memory: %ldk freed\n", (&__init_end - &__init_begin) >> 10);
}
#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
unsigned long p;
for (p = start; p < end; p += PAGE_SIZE) {
ClearPageReserved(virt_to_page(p));
init_page_count(virt_to_page(p));
free_page(p);
totalram_pages++;
}
printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
}
#endif
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