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/*
* linux/arch/arm/mm/init.c
*
* Copyright (C) 1995-2000 Russell King
*
* 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/config.h>
#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/swapctl.h>
#include <linux/smp.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/blk.h>
#include <asm/segment.h>
#include <asm/mach-types.h>
#include <asm/pgalloc.h>
#include <asm/dma.h>
#include <asm/hardware.h>
#include <asm/setup.h>
#include <asm/mach/arch.h>
#include <asm/mach/map.h>
#ifndef CONFIG_DISCONTIGMEM
#define NR_NODES 1
#else
#define NR_NODES 4
#endif
#ifdef CONFIG_CPU_32
#define TABLE_OFFSET (PTRS_PER_PTE)
#else
#define TABLE_OFFSET 0
#endif
#define TABLE_SIZE ((TABLE_OFFSET + PTRS_PER_PTE) * sizeof(void *))
static unsigned long totalram_pages;
extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
extern char _stext, _text, _etext, _end, __init_begin, __init_end;
/*
* The sole use of this is to pass memory configuration
* data from paging_init to mem_init.
*/
static struct meminfo meminfo __initdata = { 0, };
/*
* empty_zero_page is a special page that is used for
* zero-initialized data and COW.
*/
struct page *empty_zero_page;
#ifndef CONFIG_NO_PGT_CACHE
struct pgtable_cache_struct quicklists;
int do_check_pgt_cache(int low, int high)
{
int freed = 0;
if(pgtable_cache_size > high) {
do {
if(pgd_quicklist) {
free_pgd_slow(get_pgd_fast());
freed++;
}
if(pmd_quicklist) {
pmd_free_slow(pmd_alloc_one_fast(NULL, 0));
freed++;
}
if(pte_quicklist) {
pte_free_slow(pte_alloc_one_fast(NULL, 0));
freed++;
}
} while(pgtable_cache_size > low);
}
return freed;
}
#else
int do_check_pgt_cache(int low, int high)
{
return 0;
}
#endif
/* This is currently broken
* PG_skip is used on sparc/sparc64 architectures to "skip" certain
* parts of the address space.
*
* #define PG_skip 10
* #define PageSkip(page) (machine_is_riscpc() && test_bit(PG_skip, &(page)->flags))
* if (PageSkip(page)) {
* page = page->next_hash;
* if (page == NULL)
* break;
* }
*/
void show_mem(void)
{
int free = 0, total = 0, reserved = 0;
int shared = 0, cached = 0, slab = 0, node;
printk("Mem-info:\n");
show_free_areas();
printk("Free swap: %6dkB\n",nr_swap_pages<<(PAGE_SHIFT-10));
for (node = 0; node < numnodes; node++) {
struct page *page, *end;
page = NODE_MEM_MAP(node);
end = page + NODE_DATA(node)->node_size;
do {
total++;
if (PageReserved(page))
reserved++;
else if (PageSwapCache(page))
cached++;
else if (PageSlab(page))
slab++;
else if (!page_count(page))
free++;
else
shared += atomic_read(&page->count) - 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);
#ifndef CONFIG_NO_PGT_CACHE
printk("%ld page tables cached\n", pgtable_cache_size);
#endif
show_buffers();
}
struct node_info {
unsigned int start;
unsigned int end;
int bootmap_pages;
};
#define O_PFN_DOWN(x) ((x) >> PAGE_SHIFT)
#define V_PFN_DOWN(x) O_PFN_DOWN(__pa(x))
#define O_PFN_UP(x) (PAGE_ALIGN(x) >> PAGE_SHIFT)
#define V_PFN_UP(x) O_PFN_UP(__pa(x))
#define PFN_SIZE(x) ((x) >> PAGE_SHIFT)
#define PFN_RANGE(s,e) PFN_SIZE(PAGE_ALIGN((unsigned long)(e)) - \
(((unsigned long)(s)) & PAGE_MASK))
/*
* FIXME: We really want to avoid allocating the bootmap bitmap
* over the top of the initrd. Hopefully, this is located towards
* the start of a bank, so if we allocate the bootmap bitmap at
* the end, we won't clash.
*/
static unsigned int __init
find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
{
unsigned int start_pfn, bank, bootmap_pfn;
start_pfn = V_PFN_UP(&_end);
bootmap_pfn = 0;
for (bank = 0; bank < mi->nr_banks; bank ++) {
unsigned int start, end;
if (mi->bank[bank].node != node)
continue;
start = O_PFN_UP(mi->bank[bank].start);
end = O_PFN_DOWN(mi->bank[bank].size +
mi->bank[bank].start);
if (end < start_pfn)
continue;
if (start < start_pfn)
start = start_pfn;
if (end <= start)
continue;
if (end - start >= bootmap_pages) {
bootmap_pfn = start;
break;
}
}
if (bootmap_pfn == 0)
BUG();
return bootmap_pfn;
}
/*
* Scan the memory info structure and pull out:
* - the end of memory
* - the number of nodes
* - the pfn range of each node
* - the number of bootmem bitmap pages
*/
static unsigned int __init
find_memend_and_nodes(struct meminfo *mi, struct node_info *np)
{
unsigned int i, bootmem_pages = 0, memend_pfn = 0;
for (i = 0; i < NR_NODES; i++) {
np[i].start = -1U;
np[i].end = 0;
np[i].bootmap_pages = 0;
}
for (i = 0; i < mi->nr_banks; i++) {
unsigned long start, end;
int node;
if (mi->bank[i].size == 0) {
/*
* Mark this bank with an invalid node number
*/
mi->bank[i].node = -1;
continue;
}
node = mi->bank[i].node;
if (node >= numnodes) {
numnodes = node + 1;
/*
* Make sure we haven't exceeded the maximum number
* of nodes that we have in this configuration. If
* we have, we're in trouble. (maybe we ought to
* limit, instead of bugging?)
*/
if (numnodes > NR_NODES)
BUG();
}
/*
* Get the start and end pfns for this bank
*/
start = O_PFN_UP(mi->bank[i].start);
end = O_PFN_DOWN(mi->bank[i].start + mi->bank[i].size);
if (np[node].start > start)
np[node].start = start;
if (np[node].end < end)
np[node].end = end;
if (memend_pfn < end)
memend_pfn = end;
}
/*
* Calculate the number of pages we require to
* store the bootmem bitmaps.
*/
for (i = 0; i < numnodes; i++) {
if (np[i].end == 0)
continue;
np[i].bootmap_pages = bootmem_bootmap_pages(np[i].end -
np[i].start);
bootmem_pages += np[i].bootmap_pages;
}
/*
* This doesn't seem to be used by the Linux memory
* manager any more. If we can get rid of it, we
* also get rid of some of the stuff above as well.
*/
max_low_pfn = memend_pfn - O_PFN_DOWN(PHYS_OFFSET);
mi->end = memend_pfn << PAGE_SHIFT;
return bootmem_pages;
}
static int __init check_initrd(struct meminfo *mi)
{
int initrd_node = -2;
#ifdef CONFIG_BLK_DEV_INITRD
/*
* Make sure that the initrd is within a valid area of
* memory.
*/
if (initrd_start) {
unsigned long phys_initrd_start, phys_initrd_end;
unsigned int i;
phys_initrd_start = __pa(initrd_start);
phys_initrd_end = __pa(initrd_end);
for (i = 0; i < mi->nr_banks; i++) {
unsigned long bank_end;
bank_end = mi->bank[i].start + mi->bank[i].size;
if (mi->bank[i].start <= phys_initrd_start &&
phys_initrd_end <= bank_end)
initrd_node = mi->bank[i].node;
}
}
if (initrd_node == -1) {
printk(KERN_ERR "initrd (0x%08lx - 0x%08lx) extends beyond "
"physical memory - disabling initrd\n",
initrd_start, initrd_end);
initrd_start = initrd_end = 0;
}
#endif
return initrd_node;
}
/*
* Reserve the various regions of node 0
*/
static __init void reserve_node_zero(unsigned int bootmap_pfn, unsigned int bootmap_pages)
{
pg_data_t *pgdat = NODE_DATA(0);
/*
* Register the kernel text and data with bootmem.
* Note that this can only be in node 0.
*/
reserve_bootmem_node(pgdat, __pa(&_stext), &_end - &_stext);
#ifdef CONFIG_CPU_32
/*
* Reserve the page tables. These are already in use,
* and can only be in node 0.
*/
reserve_bootmem_node(pgdat, __pa(swapper_pg_dir),
PTRS_PER_PGD * sizeof(void *));
#endif
/*
* And don't forget to reserve the allocator bitmap,
* which will be freed later.
*/
reserve_bootmem_node(pgdat, bootmap_pfn << PAGE_SHIFT,
bootmap_pages << PAGE_SHIFT);
/*
* Hmm... This should go elsewhere, but we really really
* need to stop things allocating the low memory; we need
* a better implementation of GFP_DMA which does not assume
* that DMA-able memory starts at zero.
*/
if (machine_is_integrator())
reserve_bootmem_node(pgdat, 0, __pa(swapper_pg_dir));
/*
* These should likewise go elsewhere. They pre-reserve
* the screen memory region at the start of main system
* memory.
*/
if (machine_is_archimedes() || machine_is_a5k())
reserve_bootmem_node(pgdat, 0x02000000, 0x00080000);
if (machine_is_edb7211())
reserve_bootmem_node(pgdat, 0xc0000000, 0x00020000);
if (machine_is_p720t())
reserve_bootmem_node(pgdat, PHYS_OFFSET, 0x00014000);
#ifdef CONFIG_SA1111
/*
* Because of the SA1111 DMA bug, we want to preserve
* our precious DMA-able memory...
*/
reserve_bootmem_node(pgdat, PHYS_OFFSET, __pa(swapper_pg_dir)-PHYS_OFFSET);
#endif
}
/*
* Register all available RAM in this node with the bootmem allocator.
*/
static inline void free_bootmem_node_bank(int node, struct meminfo *mi)
{
pg_data_t *pgdat = NODE_DATA(node);
int bank;
for (bank = 0; bank < mi->nr_banks; bank++)
if (mi->bank[bank].node == node)
free_bootmem_node(pgdat, mi->bank[bank].start,
mi->bank[bank].size);
}
/*
* Initialise the bootmem allocator for all nodes. This is called
* early during the architecture specific initialisation.
*/
void __init bootmem_init(struct meminfo *mi)
{
struct node_info node_info[NR_NODES], *np = node_info;
unsigned int bootmap_pages, bootmap_pfn, map_pg;
int node, initrd_node;
bootmap_pages = find_memend_and_nodes(mi, np);
bootmap_pfn = find_bootmap_pfn(0, mi, bootmap_pages);
initrd_node = check_initrd(mi);
map_pg = bootmap_pfn;
/*
* Initialise the bootmem nodes.
*
* What we really want to do is:
*
* unmap_all_regions_except_kernel();
* for_each_node_in_reverse_order(node) {
* map_node(node);
* allocate_bootmem_map(node);
* init_bootmem_node(node);
* free_bootmem_node(node);
* }
*
* but this is a 2.5-type change. For now, we just set
* the nodes up in reverse order.
*
* (we could also do with rolling bootmem_init and paging_init
* into one generic "memory_init" type function).
*/
np += numnodes - 1;
for (node = numnodes - 1; node >= 0; node--, np--) {
/*
* If there are no pages in this node, ignore it.
* Note that node 0 must always have some pages.
*/
if (np->end == 0) {
if (node == 0)
BUG();
continue;
}
/*
* Initialise the bootmem allocator.
*/
init_bootmem_node(NODE_DATA(node), map_pg, np->start, np->end);
free_bootmem_node_bank(node, mi);
map_pg += np->bootmap_pages;
/*
* If this is node 0, we need to reserve some areas ASAP -
* we may use bootmem on node 0 to setup the other nodes.
*/
if (node == 0)
reserve_node_zero(bootmap_pfn, bootmap_pages);
}
#ifdef CONFIG_BLK_DEV_INITRD
if (initrd_node >= 0)
reserve_bootmem_node(NODE_DATA(initrd_node), __pa(initrd_start),
initrd_end - initrd_start);
#endif
if (map_pg != bootmap_pfn + bootmap_pages)
BUG();
}
/*
* paging_init() sets up the page tables, initialises the zone memory
* maps, and sets up the zero page, bad page and bad page tables.
*/
void __init paging_init(struct meminfo *mi, struct machine_desc *mdesc)
{
void *zero_page;
int node;
memcpy(&meminfo, mi, sizeof(meminfo));
/*
* allocate the zero page. Note that we count on this going ok.
*/
zero_page = alloc_bootmem_low_pages(PAGE_SIZE);
/*
* initialise the page tables.
*/
memtable_init(mi);
if (mdesc->map_io)
mdesc->map_io();
flush_tlb_all();
/*
* initialise the zones within each node
*/
for (node = 0; node < numnodes; node++) {
unsigned long zone_size[MAX_NR_ZONES];
unsigned long zhole_size[MAX_NR_ZONES];
struct bootmem_data *bdata;
pg_data_t *pgdat;
int i;
/*
* Initialise the zone size information.
*/
for (i = 0; i < MAX_NR_ZONES; i++) {
zone_size[i] = 0;
zhole_size[i] = 0;
}
pgdat = NODE_DATA(node);
bdata = pgdat->bdata;
/*
* The size of this node has already been determined.
* If we need to do anything fancy with the allocation
* of this memory to the zones, now is the time to do
* it.
*/
zone_size[0] = bdata->node_low_pfn -
(bdata->node_boot_start >> PAGE_SHIFT);
/*
* If this zone has zero size, skip it.
*/
if (!zone_size[0])
continue;
/*
* For each bank in this node, calculate the size of the
* holes. holes = node_size - sum(bank_sizes_in_node)
*/
zhole_size[0] = zone_size[0];
for (i = 0; i < mi->nr_banks; i++) {
if (mi->bank[i].node != node)
continue;
zhole_size[0] -= mi->bank[i].size >> PAGE_SHIFT;
}
/*
* Adjust the sizes according to any special
* requirements for this machine type.
*/
arch_adjust_zones(node, zone_size, zhole_size);
free_area_init_node(node, pgdat, 0, zone_size,
bdata->node_boot_start, zhole_size);
}
/*
* finish off the bad pages once
* the mem_map is initialised
*/
memzero(zero_page, PAGE_SIZE);
empty_zero_page = virt_to_page(zero_page);
flush_dcache_page(empty_zero_page);
}
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);
set_page_count(page, 1);
free_page(addr);
totalram_pages++;
}
if (size && s)
printk("Freeing %s memory: %dK\n", s, size);
}
/*
* mem_init() marks the free areas in the mem_map and tells us how much
* memory is free. This is done after various parts of the system have
* claimed their memory after the kernel image.
*/
void __init mem_init(void)
{
unsigned int codepages, datapages, initpages;
int i, node;
codepages = &_etext - &_text;
datapages = &_end - &_etext;
initpages = &__init_end - &__init_begin;
high_memory = (void *)__va(meminfo.end);
max_mapnr = virt_to_page(high_memory) - mem_map;
/*
* We may have non-contiguous memory.
*/
if (meminfo.nr_banks != 1)
create_memmap_holes(&meminfo);
/* this will put all unused low memory onto the freelists */
for (node = 0; node < numnodes; node++) {
pg_data_t *pgdat = NODE_DATA(node);
if (pgdat->node_size != 0)
totalram_pages += free_all_bootmem_node(pgdat);
}
#ifdef CONFIG_SA1111
/* now that our DMA memory is actually so designated, we can free it */
free_area(PAGE_OFFSET, (unsigned long)swapper_pg_dir, NULL);
#endif
/*
* Since our memory may not be contiguous, calculate the
* real number of pages we have in this system
*/
printk(KERN_INFO "Memory:");
num_physpages = 0;
for (i = 0; i < meminfo.nr_banks; i++) {
num_physpages += meminfo.bank[i].size >> PAGE_SHIFT;
printk(" %ldMB", meminfo.bank[i].size >> 20);
}
printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
"%dK data, %dK init)\n",
(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
codepages >> 10, datapages >> 10, initpages >> 10);
if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
extern int sysctl_overcommit_memory;
/*
* On a machine this small we won't get
* anywhere without overcommit, so turn
* it on by default.
*/
sysctl_overcommit_memory = 1;
}
}
void free_initmem(void)
{
if (!machine_is_integrator()) {
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
void si_meminfo(struct sysinfo *val)
{
val->totalram = totalram_pages;
val->sharedram = 0;
val->freeram = nr_free_pages();
val->bufferram = atomic_read(&buffermem_pages);
val->totalhigh = 0;
val->freehigh = 0;
val->mem_unit = PAGE_SIZE;
}
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