WSL2-Linux-Kernel/arch/arm/mm/init.c

504 строки
12 KiB
C

/*
* linux/arch/arm/mm/init.c
*
* Copyright (C) 1995-2005 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/kernel.h>
#include <linux/errno.h>
#include <linux/swap.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/mman.h>
#include <linux/nodemask.h>
#include <linux/initrd.h>
#include <asm/mach-types.h>
#include <asm/setup.h>
#include <asm/sizes.h>
#include <asm/tlb.h>
#include <asm/mach/arch.h>
#include <asm/mach/map.h>
#include "mm.h"
extern void _text, _etext, __data_start, _end, __init_begin, __init_end;
extern unsigned long phys_initrd_start;
extern unsigned long phys_initrd_size;
/*
* This is used to pass memory configuration data from paging_init
* to mem_init, and by show_mem() to skip holes in the memory map.
*/
static struct meminfo meminfo = { 0, };
#define for_each_nodebank(iter,mi,no) \
for (iter = 0; iter < mi->nr_banks; iter++) \
if (mi->bank[iter].node == no)
void show_mem(void)
{
int free = 0, total = 0, reserved = 0;
int shared = 0, cached = 0, slab = 0, node, i;
struct meminfo * mi = &meminfo;
printk("Mem-info:\n");
show_free_areas();
for_each_online_node(node) {
pg_data_t *n = NODE_DATA(node);
struct page *map = n->node_mem_map - n->node_start_pfn;
for_each_nodebank (i,mi,node) {
unsigned int pfn1, pfn2;
struct page *page, *end;
pfn1 = __phys_to_pfn(mi->bank[i].start);
pfn2 = __phys_to_pfn(mi->bank[i].size + mi->bank[i].start);
page = map + pfn1;
end = map + pfn2;
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);
}
/*
* 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 = PAGE_ALIGN(__pa(&_end)) >> PAGE_SHIFT;
bootmap_pfn = 0;
for_each_nodebank(bank, mi, node) {
unsigned int start, end;
start = mi->bank[bank].start >> PAGE_SHIFT;
end = (mi->bank[bank].size +
mi->bank[bank].start) >> PAGE_SHIFT;
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;
}
static int __init check_initrd(struct meminfo *mi)
{
int initrd_node = -2;
#ifdef CONFIG_BLK_DEV_INITRD
unsigned long end = phys_initrd_start + phys_initrd_size;
/*
* Make sure that the initrd is within a valid area of
* memory.
*/
if (phys_initrd_size) {
unsigned int i;
initrd_node = -1;
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 &&
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",
phys_initrd_start, end);
phys_initrd_start = phys_initrd_size = 0;
}
#endif
return initrd_node;
}
static inline void map_memory_bank(struct membank *bank)
{
#ifdef CONFIG_MMU
struct map_desc map;
map.pfn = __phys_to_pfn(bank->start);
map.virtual = __phys_to_virt(bank->start);
map.length = bank->size;
map.type = MT_MEMORY;
create_mapping(&map);
#endif
}
static unsigned long __init
bootmem_init_node(int node, int initrd_node, struct meminfo *mi)
{
unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
unsigned long start_pfn, end_pfn, boot_pfn;
unsigned int boot_pages;
pg_data_t *pgdat;
int i;
start_pfn = -1UL;
end_pfn = 0;
/*
* Calculate the pfn range, and map the memory banks for this node.
*/
for_each_nodebank(i, mi, node) {
struct membank *bank = &mi->bank[i];
unsigned long start, end;
start = bank->start >> PAGE_SHIFT;
end = (bank->start + bank->size) >> PAGE_SHIFT;
if (start_pfn > start)
start_pfn = start;
if (end_pfn < end)
end_pfn = end;
map_memory_bank(bank);
}
/*
* If there is no memory in this node, ignore it.
*/
if (end_pfn == 0)
return end_pfn;
/*
* Allocate the bootmem bitmap page.
*/
boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
boot_pfn = find_bootmap_pfn(node, mi, boot_pages);
/*
* Initialise the bootmem allocator for this node, handing the
* memory banks over to bootmem.
*/
node_set_online(node);
pgdat = NODE_DATA(node);
init_bootmem_node(pgdat, boot_pfn, start_pfn, end_pfn);
for_each_nodebank(i, mi, node)
free_bootmem_node(pgdat, mi->bank[i].start, mi->bank[i].size);
/*
* Reserve the bootmem bitmap for this node.
*/
reserve_bootmem_node(pgdat, boot_pfn << PAGE_SHIFT,
boot_pages << PAGE_SHIFT, BOOTMEM_DEFAULT);
#ifdef CONFIG_BLK_DEV_INITRD
/*
* If the initrd is in this node, reserve its memory.
*/
if (node == initrd_node) {
reserve_bootmem_node(pgdat, phys_initrd_start,
phys_initrd_size, BOOTMEM_DEFAULT);
initrd_start = __phys_to_virt(phys_initrd_start);
initrd_end = initrd_start + phys_initrd_size;
}
#endif
/*
* Finally, reserve any node zero regions.
*/
if (node == 0)
reserve_node_zero(pgdat);
/*
* initialise the zones within this node.
*/
memset(zone_size, 0, sizeof(zone_size));
memset(zhole_size, 0, sizeof(zhole_size));
/*
* 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] = end_pfn - start_pfn;
/*
* 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_each_nodebank(i, mi, node)
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, zone_size, start_pfn, zhole_size);
return end_pfn;
}
void __init bootmem_init(struct meminfo *mi)
{
unsigned long memend_pfn = 0;
int node, initrd_node, i;
/*
* Invalidate the node number for empty or invalid memory banks
*/
for (i = 0; i < mi->nr_banks; i++)
if (mi->bank[i].size == 0 || mi->bank[i].node >= MAX_NUMNODES)
mi->bank[i].node = -1;
memcpy(&meminfo, mi, sizeof(meminfo));
/*
* Locate which node contains the ramdisk image, if any.
*/
initrd_node = check_initrd(mi);
/*
* Run through each node initialising the bootmem allocator.
*/
for_each_node(node) {
unsigned long end_pfn;
end_pfn = bootmem_init_node(node, initrd_node, mi);
/*
* Remember the highest memory PFN.
*/
if (end_pfn > memend_pfn)
memend_pfn = end_pfn;
}
high_memory = __va(memend_pfn << PAGE_SHIFT);
/*
* This doesn't seem to be used by the Linux memory manager any
* more, but is used by ll_rw_block. If we can get rid of it, we
* also get rid of some of the stuff above as well.
*
* Note: max_low_pfn and max_pfn reflect the number of _pages_ in
* the system, not the maximum PFN.
*/
max_pfn = max_low_pfn = memend_pfn - PHYS_PFN_OFFSET;
}
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\n", s, size);
}
static inline void
free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
{
struct page *start_pg, *end_pg;
unsigned long pg, pgend;
/*
* Convert start_pfn/end_pfn to a struct page pointer.
*/
start_pg = pfn_to_page(start_pfn);
end_pg = pfn_to_page(end_pfn);
/*
* Convert to physical addresses, and
* round start upwards and end downwards.
*/
pg = PAGE_ALIGN(__pa(start_pg));
pgend = __pa(end_pg) & PAGE_MASK;
/*
* If there are free pages between these,
* free the section of the memmap array.
*/
if (pg < pgend)
free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
}
/*
* The mem_map array can get very big. Free the unused area of the memory map.
*/
static void __init free_unused_memmap_node(int node, struct meminfo *mi)
{
unsigned long bank_start, prev_bank_end = 0;
unsigned int i;
/*
* [FIXME] This relies on each bank being in address order. This
* may not be the case, especially if the user has provided the
* information on the command line.
*/
for_each_nodebank(i, mi, node) {
bank_start = mi->bank[i].start >> PAGE_SHIFT;
if (bank_start < prev_bank_end) {
printk(KERN_ERR "MEM: unordered memory banks. "
"Not freeing memmap.\n");
break;
}
/*
* If we had a previous bank, and there is a space
* between the current bank and the previous, free it.
*/
if (prev_bank_end && prev_bank_end != bank_start)
free_memmap(node, prev_bank_end, bank_start);
prev_bank_end = (mi->bank[i].start +
mi->bank[i].size) >> PAGE_SHIFT;
}
}
/*
* 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 - &__data_start;
initpages = &__init_end - &__init_begin;
#ifndef CONFIG_DISCONTIGMEM
max_mapnr = virt_to_page(high_memory) - mem_map;
#endif
/* this will put all unused low memory onto the freelists */
for_each_online_node(node) {
pg_data_t *pgdat = NODE_DATA(node);
free_unused_memmap_node(node, &meminfo);
if (pgdat->node_spanned_pages != 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 = OVERCOMMIT_ALWAYS;
}
}
void free_initmem(void)
{
if (!machine_is_integrator() && !machine_is_cintegrator()) {
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