/*
* Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com)
* Licensed under the GPL
*/
#include "linux/stddef.h"
#include "linux/kernel.h"
#include "linux/mm.h"
#include "linux/bootmem.h"
#include "linux/swap.h"
#include "linux/highmem.h"
#include "linux/gfp.h"
#include "asm/page.h"
#include "asm/fixmap.h"
#include "asm/pgalloc.h"
#include "user_util.h"
#include "kern_util.h"
#include "kern.h"
#include "mem_user.h"
#include "uml_uaccess.h"
#include "os.h"
extern char __binary_start;
/* Changed during early boot */
unsigned long *empty_zero_page = NULL;
unsigned long *empty_bad_page = NULL;
pgd_t swapper_pg_dir[PTRS_PER_PGD];
unsigned long highmem;
int kmalloc_ok = 0;
static unsigned long brk_end;
void unmap_physmem(void)
{
os_unmap_memory((void *) brk_end, uml_reserved - brk_end);
}
static void map_cb(void *unused)
{
map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
}
#ifdef CONFIG_HIGHMEM
static void setup_highmem(unsigned long highmem_start,
unsigned long highmem_len)
{
struct page *page;
unsigned long highmem_pfn;
int i;
highmem_pfn = __pa(highmem_start) >> PAGE_SHIFT;
for(i = 0; i < highmem_len >> PAGE_SHIFT; i++){
page = &mem_map[highmem_pfn + i];
ClearPageReserved(page);
set_bit(PG_highmem, &page->flags);
set_page_count(page, 1);
__free_page(page);
}
}
#endif
void mem_init(void)
{
unsigned long start;
max_low_pfn = (high_physmem - uml_physmem) >> PAGE_SHIFT;
/* clear the zero-page */
memset((void *) empty_zero_page, 0, PAGE_SIZE);
/* Map in the area just after the brk now that kmalloc is about
* to be turned on.
*/
brk_end = (unsigned long) UML_ROUND_UP(sbrk(0));
map_cb(NULL);
initial_thread_cb(map_cb, NULL);
free_bootmem(__pa(brk_end), uml_reserved - brk_end);
uml_reserved = brk_end;
/* Fill in any hole at the start of the binary */
start = (unsigned long) &__binary_start & PAGE_MASK;
if(uml_physmem != start){
map_memory(uml_physmem, __pa(uml_physmem), start - uml_physmem,
1, 1, 0);
}
/* this will put all low memory onto the freelists */
totalram_pages = free_all_bootmem();
totalhigh_pages = highmem >> PAGE_SHIFT;
totalram_pages += totalhigh_pages;
num_physpages = totalram_pages;
max_pfn = totalram_pages;
printk(KERN_INFO "Memory: %luk available\n",
(unsigned long) nr_free_pages() << (PAGE_SHIFT-10));
kmalloc_ok = 1;
#ifdef CONFIG_HIGHMEM
setup_highmem(end_iomem, highmem);
#endif
}
/*
* Create a page table and place a pointer to it in a middle page
* directory entry.
*/
static void __init one_page_table_init(pmd_t *pmd)
{
if (pmd_none(*pmd)) {
pte_t *pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
set_pmd(pmd, __pmd(_KERNPG_TABLE +
(unsigned long) __pa(pte)));
if (pte != pte_offset_kernel(pmd, 0))
BUG();
}
}
static void __init one_md_table_init(pud_t *pud)
{
#ifdef CONFIG_3_LEVEL_PGTABLES
pmd_t *pmd_table = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE);
set_pud(pud, __pud(_KERNPG_TABLE + (unsigned long) __pa(pmd_table)));
if (pmd_table != pmd_offset(pud, 0))
BUG();
#endif
}
static void __init fixrange_init(unsigned long start, unsigned long end,
pgd_t *pgd_base)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
int i, j;
unsigned long vaddr;
vaddr = start;
i = pgd_index(vaddr);
j = pmd_index(vaddr);
pgd = pgd_base + i;
for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
pud = pud_offset(pgd, vaddr);
if (pud_none(*pud))
one_md_table_init(pud);
pmd = pmd_offset(pud, vaddr);
for (; (j < PTRS_PER_PMD) && (vaddr != end); pmd++, j++) {
one_page_table_init(pmd);
vaddr += PMD_SIZE;
}
j = 0;
}
}
#ifdef CONFIG_HIGHMEM
pte_t *kmap_pte;
pgprot_t kmap_prot;
#define kmap_get_fixmap_pte(vaddr) \
pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)),\
(vaddr)), (vaddr))
static void __init kmap_init(void)
{
unsigned long kmap_vstart;
/* cache the first kmap pte */
kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
kmap_prot = PAGE_KERNEL;
}
static void init_highmem(void)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
unsigned long vaddr;
/*
* Permanent kmaps:
*/
vaddr = PKMAP_BASE;
fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, swapper_pg_dir);
pgd = swapper_pg_dir + pgd_index(vaddr);
pud = pud_offset(pgd, vaddr);
pmd = pmd_offset(pud, vaddr);
pte = pte_offset_kernel(pmd, vaddr);
pkmap_page_table = pte;
kmap_init();
}
#endif /* CONFIG_HIGHMEM */
static void __init fixaddr_user_init( void)
{
#if CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
long size = FIXADDR_USER_END - FIXADDR_USER_START;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
unsigned long paddr, vaddr = FIXADDR_USER_START;
if ( ! size )
return;
fixrange_init( FIXADDR_USER_START, FIXADDR_USER_END, swapper_pg_dir);
paddr = (unsigned long)alloc_bootmem_low_pages( size);
memcpy( (void *)paddr, (void *)FIXADDR_USER_START, size);
paddr = __pa(paddr);
for ( ; size > 0; size-=PAGE_SIZE, vaddr+=PAGE_SIZE, paddr+=PAGE_SIZE){
pgd = swapper_pg_dir + pgd_index(vaddr);
pud = pud_offset(pgd, vaddr);
pmd = pmd_offset(pud, vaddr);
pte = pte_offset_kernel(pmd, vaddr);
pte_set_val( (*pte), paddr, PAGE_READONLY);
}
#endif
}
void paging_init(void)
{
unsigned long zones_size[MAX_NR_ZONES], vaddr;
int i;
empty_zero_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
empty_bad_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
for(i=0;i<sizeof(zones_size)/sizeof(zones_size[0]);i++)
zones_size[i] = 0;
zones_size[0] = (end_iomem >> PAGE_SHIFT) - (uml_physmem >> PAGE_SHIFT);
zones_size[2] = highmem >> PAGE_SHIFT;
free_area_init(zones_size);
/*
* Fixed mappings, only the page table structure has to be
* created - mappings will be set by set_fixmap():
*/
vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
fixaddr_user_init();
#ifdef CONFIG_HIGHMEM
init_highmem();
#endif
}
struct page *arch_validate(struct page *page, int mask, int order)
{
unsigned long addr, zero = 0;
int i;
again:
if(page == NULL) return(page);
if(PageHighMem(page)) return(page);
addr = (unsigned long) page_address(page);
for(i = 0; i < (1 << order); i++){
current->thread.fault_addr = (void *) addr;
if(__do_copy_to_user((void __user *) addr, &zero,
sizeof(zero),
¤t->thread.fault_addr,
¤t->thread.fault_catcher)){
if(!(mask & __GFP_WAIT)) return(NULL);
else break;
}
addr += PAGE_SIZE;
}
if(i == (1 << order)) return(page);
page = alloc_pages(mask, order);
goto again;
}
/* This can't do anything because nothing in the kernel image can be freed
* since it's not in kernel physical memory.
*/
void free_initmem(void)
{
}
#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
if (start < end)
printk ("Freeing initrd memory: %ldk freed\n",
(end - start) >> 10);
for (; start < end; start += PAGE_SIZE) {
ClearPageReserved(virt_to_page(start));
set_page_count(virt_to_page(start), 1);
free_page(start);
totalram_pages++;
}
}
#endif
void show_mem(void)
{
int pfn, total = 0, reserved = 0;
int shared = 0, cached = 0;
int highmem = 0;
struct page *page;
printk("Mem-info:\n");
show_free_areas();
printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
pfn = max_mapnr;
while(pfn-- > 0) {
page = pfn_to_page(pfn);
total++;
if(PageHighMem(page))
highmem++;
if(PageReserved(page))
reserved++;
else if(PageSwapCache(page))
cached++;
else if(page_count(page))
shared += page_count(page) - 1;
}
printk("%d pages of RAM\n", total);
printk("%d pages of HIGHMEM\n", highmem);
printk("%d reserved pages\n", reserved);
printk("%d pages shared\n", shared);
printk("%d pages swap cached\n", cached);
}
/*
* Allocate and free page tables.
*/
pgd_t *pgd_alloc(struct mm_struct *mm)
{
pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
if (pgd) {
memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
memcpy(pgd + USER_PTRS_PER_PGD,
swapper_pg_dir + USER_PTRS_PER_PGD,
(PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
}
return pgd;
}
void pgd_free(pgd_t *pgd)
{
free_page((unsigned long) pgd);
}
pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
{
pte_t *pte;
pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
return pte;
}
struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
{
struct page *pte;
pte = alloc_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
return pte;
}
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
* adjust the settings for this buffer only. This must remain at the end
* of the file.
* ---------------------------------------------------------------------------
* Local variables:
* c-file-style: "linux"
* End:
*/
