Staging
v0.6.0
v0.6.0
https://github.com/torvalds/linux
Tip revision: 669df1b478803f49a356528d290af7bf442eb3be authored by Linus Torvalds on 01 January 2007, 00:53:20 UTC
Linux 2.6.20-rc3
Linux 2.6.20-rc3
Tip revision: 669df1b
init.c
/*
* Copyright (C) 2004-2006 Atmel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/init.h>
#include <linux/initrd.h>
#include <linux/mmzone.h>
#include <linux/bootmem.h>
#include <linux/pagemap.h>
#include <linux/pfn.h>
#include <linux/nodemask.h>
#include <asm/page.h>
#include <asm/mmu_context.h>
#include <asm/tlb.h>
#include <asm/io.h>
#include <asm/dma.h>
#include <asm/setup.h>
#include <asm/sections.h>
DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
pgd_t swapper_pg_dir[PTRS_PER_PGD];
struct page *empty_zero_page;
/*
* Cache of MMU context last used.
*/
unsigned long mmu_context_cache = NO_CONTEXT;
#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 total = 0, reserved = 0, cached = 0;
int slab = 0, free = 0, shared = 0;
pg_data_t *pgdat;
printk("Mem-info:\n");
show_free_areas();
for_each_online_pgdat(pgdat) {
struct page *page, *end;
page = pgdat->node_mem_map;
end = page + pgdat->node_spanned_pages;
do {
total++;
if (PageReserved(page))
reserved++;
else if (PageSwapCache(page))
cached++;
else if (PageSlab(page))
slab++;
else if (!page_count(page))
free++;
else
shared += page_count(page) - 1;
page++;
} while (page < end);
}
printk ("%d pages of RAM\n", total);
printk ("%d free pages\n", free);
printk ("%d reserved pages\n", reserved);
printk ("%d slab pages\n", slab);
printk ("%d pages shared\n", shared);
printk ("%d pages swap cached\n", cached);
}
static void __init print_memory_map(const char *what,
struct tag_mem_range *mem)
{
printk ("%s:\n", what);
for (; mem; mem = mem->next) {
printk (" %08lx - %08lx\n",
(unsigned long)mem->addr,
(unsigned long)(mem->addr + mem->size));
}
}
#define MAX_LOWMEM HIGHMEM_START
#define MAX_LOWMEM_PFN PFN_DOWN(MAX_LOWMEM)
/*
* Sort a list of memory regions in-place by ascending address.
*
* We're using bubble sort because we only have singly linked lists
* with few elements.
*/
static void __init sort_mem_list(struct tag_mem_range **pmem)
{
int done;
struct tag_mem_range **a, **b;
if (!*pmem)
return;
do {
done = 1;
a = pmem, b = &(*pmem)->next;
while (*b) {
if ((*a)->addr > (*b)->addr) {
struct tag_mem_range *tmp;
tmp = (*b)->next;
(*b)->next = *a;
*a = *b;
*b = tmp;
done = 0;
}
a = &(*a)->next;
b = &(*a)->next;
}
} while (!done);
}
/*
* Find a free memory region large enough for storing the
* bootmem bitmap.
*/
static unsigned long __init
find_bootmap_pfn(const struct tag_mem_range *mem)
{
unsigned long bootmap_pages, bootmap_len;
unsigned long node_pages = PFN_UP(mem->size);
unsigned long bootmap_addr = mem->addr;
struct tag_mem_range *reserved = mem_reserved;
struct tag_mem_range *ramdisk = mem_ramdisk;
unsigned long kern_start = virt_to_phys(_stext);
unsigned long kern_end = virt_to_phys(_end);
bootmap_pages = bootmem_bootmap_pages(node_pages);
bootmap_len = bootmap_pages << PAGE_SHIFT;
/*
* Find a large enough region without reserved pages for
* storing the bootmem bitmap. We can take advantage of the
* fact that all lists have been sorted.
*
* We have to check explicitly reserved regions as well as the
* kernel image and any RAMDISK images...
*
* Oh, and we have to make sure we don't overwrite the taglist
* since we're going to use it until the bootmem allocator is
* fully up and running.
*/
while (1) {
if ((bootmap_addr < kern_end) &&
((bootmap_addr + bootmap_len) > kern_start))
bootmap_addr = kern_end;
while (reserved &&
(bootmap_addr >= (reserved->addr + reserved->size)))
reserved = reserved->next;
if (reserved &&
((bootmap_addr + bootmap_len) >= reserved->addr)) {
bootmap_addr = reserved->addr + reserved->size;
continue;
}
while (ramdisk &&
(bootmap_addr >= (ramdisk->addr + ramdisk->size)))
ramdisk = ramdisk->next;
if (!ramdisk ||
((bootmap_addr + bootmap_len) < ramdisk->addr))
break;
bootmap_addr = ramdisk->addr + ramdisk->size;
}
if ((PFN_UP(bootmap_addr) + bootmap_len) >= (mem->addr + mem->size))
return ~0UL;
return PFN_UP(bootmap_addr);
}
void __init setup_bootmem(void)
{
unsigned bootmap_size;
unsigned long first_pfn, bootmap_pfn, pages;
unsigned long max_pfn, max_low_pfn;
unsigned long kern_start = virt_to_phys(_stext);
unsigned long kern_end = virt_to_phys(_end);
unsigned node = 0;
struct tag_mem_range *bank, *res;
sort_mem_list(&mem_phys);
sort_mem_list(&mem_reserved);
print_memory_map("Physical memory", mem_phys);
print_memory_map("Reserved memory", mem_reserved);
nodes_clear(node_online_map);
if (mem_ramdisk) {
#ifdef CONFIG_BLK_DEV_INITRD
initrd_start = (unsigned long)__va(mem_ramdisk->addr);
initrd_end = initrd_start + mem_ramdisk->size;
print_memory_map("RAMDISK images", mem_ramdisk);
if (mem_ramdisk->next)
printk(KERN_WARNING
"Warning: Only the first RAMDISK image "
"will be used\n");
sort_mem_list(&mem_ramdisk);
#else
printk(KERN_WARNING "RAM disk image present, but "
"no initrd support in kernel!\n");
#endif
}
if (mem_phys->next)
printk(KERN_WARNING "Only using first memory bank\n");
for (bank = mem_phys; bank; bank = NULL) {
first_pfn = PFN_UP(bank->addr);
max_low_pfn = max_pfn = PFN_DOWN(bank->addr + bank->size);
bootmap_pfn = find_bootmap_pfn(bank);
if (bootmap_pfn > max_pfn)
panic("No space for bootmem bitmap!\n");
if (max_low_pfn > MAX_LOWMEM_PFN) {
max_low_pfn = MAX_LOWMEM_PFN;
#ifndef CONFIG_HIGHMEM
/*
* Lowmem is memory that can be addressed
* directly through P1/P2
*/
printk(KERN_WARNING
"Node %u: Only %ld MiB of memory will be used.\n",
node, MAX_LOWMEM >> 20);
printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n");
#else
#error HIGHMEM is not supported by AVR32 yet
#endif
}
/* Initialize the boot-time allocator with low memory only. */
bootmap_size = init_bootmem_node(NODE_DATA(node), bootmap_pfn,
first_pfn, max_low_pfn);
printk("Node %u: bdata = %p, bdata->node_bootmem_map = %p\n",
node, NODE_DATA(node)->bdata,
NODE_DATA(node)->bdata->node_bootmem_map);
/*
* Register fully available RAM pages with the bootmem
* allocator.
*/
pages = max_low_pfn - first_pfn;
free_bootmem_node (NODE_DATA(node), PFN_PHYS(first_pfn),
PFN_PHYS(pages));
/*
* Reserve space for the kernel image (if present in
* this node)...
*/
if ((kern_start >= PFN_PHYS(first_pfn)) &&
(kern_start < PFN_PHYS(max_pfn))) {
printk("Node %u: Kernel image %08lx - %08lx\n",
node, kern_start, kern_end);
reserve_bootmem_node(NODE_DATA(node), kern_start,
kern_end - kern_start);
}
/* ...the bootmem bitmap... */
reserve_bootmem_node(NODE_DATA(node),
PFN_PHYS(bootmap_pfn),
bootmap_size);
/* ...any RAMDISK images... */
for (res = mem_ramdisk; res; res = res->next) {
if (res->addr > PFN_PHYS(max_pfn))
break;
if (res->addr >= PFN_PHYS(first_pfn)) {
printk("Node %u: RAMDISK %08lx - %08lx\n",
node,
(unsigned long)res->addr,
(unsigned long)(res->addr + res->size));
reserve_bootmem_node(NODE_DATA(node),
res->addr, res->size);
}
}
/* ...and any other reserved regions. */
for (res = mem_reserved; res; res = res->next) {
if (res->addr > PFN_PHYS(max_pfn))
break;
if (res->addr >= PFN_PHYS(first_pfn)) {
printk("Node %u: Reserved %08lx - %08lx\n",
node,
(unsigned long)res->addr,
(unsigned long)(res->addr + res->size));
reserve_bootmem_node(NODE_DATA(node),
res->addr, res->size);
}
}
node_set_online(node);
}
}
/*
* paging_init() sets up the page tables
*
* This routine also unmaps the page at virtual kernel address 0, so
* that we can trap those pesky NULL-reference errors in the kernel.
*/
void __init paging_init(void)
{
extern unsigned long _evba;
void *zero_page;
int nid;
/*
* Make sure we can handle exceptions before enabling
* paging. Not that we should ever _get_ any exceptions this
* early, but you never know...
*/
printk("Exception vectors start at %p\n", &_evba);
sysreg_write(EVBA, (unsigned long)&_evba);
/*
* Since we are ready to handle exceptions now, we should let
* the CPU generate them...
*/
__asm__ __volatile__ ("csrf %0" : : "i"(SR_EM_BIT));
/*
* Allocate the zero page. The allocator will panic if it
* can't satisfy the request, so no need to check.
*/
zero_page = alloc_bootmem_low_pages_node(NODE_DATA(0),
PAGE_SIZE);
{
pgd_t *pg_dir;
int i;
pg_dir = swapper_pg_dir;
sysreg_write(PTBR, (unsigned long)pg_dir);
for (i = 0; i < PTRS_PER_PGD; i++)
pgd_val(pg_dir[i]) = 0;
enable_mmu();
printk ("CPU: Paging enabled\n");
}
for_each_online_node(nid) {
pg_data_t *pgdat = NODE_DATA(nid);
unsigned long zones_size[MAX_NR_ZONES];
unsigned long low, start_pfn;
start_pfn = pgdat->bdata->node_boot_start;
start_pfn >>= PAGE_SHIFT;
low = pgdat->bdata->node_low_pfn;
memset(zones_size, 0, sizeof(zones_size));
zones_size[ZONE_NORMAL] = low - start_pfn;
printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
nid, start_pfn, low);
free_area_init_node(nid, pgdat, zones_size, start_pfn, NULL);
printk("Node %u: mem_map starts at %p\n",
pgdat->node_id, pgdat->node_mem_map);
}
mem_map = NODE_DATA(0)->node_mem_map;
memset(zero_page, 0, PAGE_SIZE);
empty_zero_page = virt_to_page(zero_page);
flush_dcache_page(empty_zero_page);
}
void __init mem_init(void)
{
int codesize, reservedpages, datasize, initsize;
int nid, i;
reservedpages = 0;
high_memory = NULL;
/* this will put all low memory onto the freelists */
for_each_online_node(nid) {
pg_data_t *pgdat = NODE_DATA(nid);
unsigned long node_pages = 0;
void *node_high_memory;
num_physpages += pgdat->node_present_pages;
if (pgdat->node_spanned_pages != 0)
node_pages = free_all_bootmem_node(pgdat);
totalram_pages += node_pages;
for (i = 0; i < node_pages; i++)
if (PageReserved(pgdat->node_mem_map + i))
reservedpages++;
node_high_memory = (void *)((pgdat->node_start_pfn
+ pgdat->node_spanned_pages)
<< PAGE_SHIFT);
if (node_high_memory > high_memory)
high_memory = node_high_memory;
}
max_mapnr = MAP_NR(high_memory);
codesize = (unsigned long)_etext - (unsigned long)_text;
datasize = (unsigned long)_edata - (unsigned long)_data;
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),
totalram_pages << (PAGE_SHIFT - 10),
codesize >> 10,
reservedpages << (PAGE_SHIFT - 10),
datasize >> 10,
initsize >> 10);
}
static inline void free_area(unsigned long addr, unsigned long end, char *s)
{
unsigned int size = (end - addr) >> 10;
for (; addr < end; addr += PAGE_SIZE) {
struct page *page = virt_to_page(addr);
ClearPageReserved(page);
init_page_count(page);
free_page(addr);
totalram_pages++;
}
if (size && s)
printk(KERN_INFO "Freeing %s memory: %dK (%lx - %lx)\n",
s, size, end - (size << 10), end);
}
void free_initmem(void)
{
free_area((unsigned long)__init_begin, (unsigned long)__init_end,
"init");
}
#ifdef CONFIG_BLK_DEV_INITRD
static int keep_initrd;
void free_initrd_mem(unsigned long start, unsigned long end)
{
if (!keep_initrd)
free_area(start, end, "initrd");
}
static int __init keepinitrd_setup(char *__unused)
{
keep_initrd = 1;
return 1;
}
__setup("keepinitrd", keepinitrd_setup);
#endif