/*
* arch/s390/mm/init.c
*
* S390 version
* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Hartmut Penner (hp@de.ibm.com)
*
* Derived from "arch/i386/mm/init.c"
* Copyright (C) 1995 Linus Torvalds
*/
#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/smp.h>
#include <linux/init.h>
#include <linux/pagemap.h>
#include <linux/bootmem.h>
#include <linux/pfn.h>
#include <linux/poison.h>
#include <linux/initrd.h>
#include <asm/processor.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/dma.h>
#include <asm/lowcore.h>
#include <asm/tlb.h>
#include <asm/tlbflush.h>
#include <asm/sections.h>
DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE)));
char empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
void show_mem(void)
{
int i, total = 0, reserved = 0;
int shared = 0, cached = 0;
struct page *page;
printk("Mem-info:\n");
show_free_areas();
i = max_mapnr;
while (i-- > 0) {
if (!pfn_valid(i))
continue;
page = pfn_to_page(i);
total++;
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 reserved pages\n", reserved);
printk("%d pages shared\n", shared);
printk("%d pages swap cached\n", cached);
printk("%lu pages dirty\n", global_page_state(NR_FILE_DIRTY));
printk("%lu pages writeback\n", global_page_state(NR_WRITEBACK));
printk("%lu pages mapped\n", global_page_state(NR_FILE_MAPPED));
printk("%lu pages slab\n",
global_page_state(NR_SLAB_RECLAIMABLE) +
global_page_state(NR_SLAB_UNRECLAIMABLE));
printk("%lu pages pagetables\n", global_page_state(NR_PAGETABLE));
}
static void __init setup_ro_region(void)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
pte_t new_pte;
unsigned long address, end;
address = ((unsigned long)&_stext) & PAGE_MASK;
end = PFN_ALIGN((unsigned long)&_eshared);
for (; address < end; address += PAGE_SIZE) {
pgd = pgd_offset_k(address);
pud = pud_offset(pgd, address);
pmd = pmd_offset(pud, address);
pte = pte_offset_kernel(pmd, address);
new_pte = mk_pte_phys(address, __pgprot(_PAGE_RO));
*pte = new_pte;
}
}
/*
* paging_init() sets up the page tables
*/
void __init paging_init(void)
{
static const int ssm_mask = 0x04000000L;
unsigned long max_zone_pfns[MAX_NR_ZONES];
unsigned long pgd_type;
init_mm.pgd = swapper_pg_dir;
S390_lowcore.kernel_asce = __pa(init_mm.pgd) & PAGE_MASK;
#ifdef CONFIG_64BIT
/* A three level page table (4TB) is enough for the kernel space. */
S390_lowcore.kernel_asce |= _ASCE_TYPE_REGION3 | _ASCE_TABLE_LENGTH;
pgd_type = _REGION3_ENTRY_EMPTY;
#else
S390_lowcore.kernel_asce |= _ASCE_TABLE_LENGTH;
pgd_type = _SEGMENT_ENTRY_EMPTY;
#endif
clear_table((unsigned long *) init_mm.pgd, pgd_type,
sizeof(unsigned long)*2048);
vmem_map_init();
setup_ro_region();
/* enable virtual mapping in kernel mode */
__ctl_load(S390_lowcore.kernel_asce, 1, 1);
__ctl_load(S390_lowcore.kernel_asce, 7, 7);
__ctl_load(S390_lowcore.kernel_asce, 13, 13);
__raw_local_irq_ssm(ssm_mask);
memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
#ifdef CONFIG_ZONE_DMA
max_zone_pfns[ZONE_DMA] = PFN_DOWN(MAX_DMA_ADDRESS);
#endif
max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
free_area_init_nodes(max_zone_pfns);
}
void __init mem_init(void)
{
unsigned long codesize, reservedpages, datasize, initsize;
max_mapnr = num_physpages = max_low_pfn;
high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
/* clear the zero-page */
memset(empty_zero_page, 0, PAGE_SIZE);
/* this will put all low memory onto the freelists */
totalram_pages += free_all_bootmem();
reservedpages = 0;
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 (%ldk kernel code, %ldk reserved, %ldk data, %ldk 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);
printk("Write protected kernel read-only data: %#lx - %#lx\n",
(unsigned long)&_stext,
PFN_ALIGN((unsigned long)&_eshared) - 1);
}
#ifdef CONFIG_DEBUG_PAGEALLOC
void kernel_map_pages(struct page *page, int numpages, int enable)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
unsigned long address;
int i;
for (i = 0; i < numpages; i++) {
address = page_to_phys(page + i);
pgd = pgd_offset_k(address);
pud = pud_offset(pgd, address);
pmd = pmd_offset(pud, address);
pte = pte_offset_kernel(pmd, address);
if (!enable) {
ptep_invalidate(&init_mm, address, pte);
continue;
}
*pte = mk_pte_phys(address, __pgprot(_PAGE_TYPE_RW));
/* Flush cpu write queue. */
mb();
}
}
#endif
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));
memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
free_page(addr);
totalram_pages++;
}
printk ("Freeing unused kernel memory: %ldk freed\n",
((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10);
}
#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));
init_page_count(virt_to_page(start));
free_page(start);
totalram_pages++;
}
}
#endif
