301 lines
7.7 KiB
C
Executable File
301 lines
7.7 KiB
C
Executable File
/*
|
|
* linux/arch/alpha/mm/init.c
|
|
*
|
|
* Copyright (C) 1995 Linus Torvalds
|
|
*/
|
|
|
|
/* 2.3.x zone allocator, 1999 Andrea Arcangeli <andrea@suse.de> */
|
|
|
|
#include <linux/pagemap.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/init.h>
|
|
#include <linux/bootmem.h> /* max_low_pfn */
|
|
#include <linux/vmalloc.h>
|
|
#include <linux/gfp.h>
|
|
|
|
#include <asm/uaccess.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/hwrpb.h>
|
|
#include <asm/dma.h>
|
|
#include <asm/mmu_context.h>
|
|
#include <asm/console.h>
|
|
#include <asm/tlb.h>
|
|
#include <asm/setup.h>
|
|
#include <asm/sections.h>
|
|
|
|
extern void die_if_kernel(char *,struct pt_regs *,long);
|
|
|
|
static struct pcb_struct original_pcb;
|
|
|
|
pgd_t *
|
|
pgd_alloc(struct mm_struct *mm)
|
|
{
|
|
pgd_t *ret, *init;
|
|
|
|
ret = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
|
|
init = pgd_offset(&init_mm, 0UL);
|
|
if (ret) {
|
|
#ifdef CONFIG_ALPHA_LARGE_VMALLOC
|
|
memcpy (ret + USER_PTRS_PER_PGD, init + USER_PTRS_PER_PGD,
|
|
(PTRS_PER_PGD - USER_PTRS_PER_PGD - 1)*sizeof(pgd_t));
|
|
#else
|
|
pgd_val(ret[PTRS_PER_PGD-2]) = pgd_val(init[PTRS_PER_PGD-2]);
|
|
#endif
|
|
|
|
/* The last PGD entry is the VPTB self-map. */
|
|
pgd_val(ret[PTRS_PER_PGD-1])
|
|
= pte_val(mk_pte(virt_to_page(ret), PAGE_KERNEL));
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
|
|
/*
|
|
* BAD_PAGE is the page that is used for page faults when linux
|
|
* is out-of-memory. Older versions of linux just did a
|
|
* do_exit(), but using this instead means there is less risk
|
|
* for a process dying in kernel mode, possibly leaving an inode
|
|
* unused etc..
|
|
*
|
|
* BAD_PAGETABLE is the accompanying page-table: it is initialized
|
|
* to point to BAD_PAGE entries.
|
|
*
|
|
* ZERO_PAGE is a special page that is used for zero-initialized
|
|
* data and COW.
|
|
*/
|
|
pmd_t *
|
|
__bad_pagetable(void)
|
|
{
|
|
memset((void *) EMPTY_PGT, 0, PAGE_SIZE);
|
|
return (pmd_t *) EMPTY_PGT;
|
|
}
|
|
|
|
pte_t
|
|
__bad_page(void)
|
|
{
|
|
memset((void *) EMPTY_PGE, 0, PAGE_SIZE);
|
|
return pte_mkdirty(mk_pte(virt_to_page(EMPTY_PGE), PAGE_SHARED));
|
|
}
|
|
|
|
static inline unsigned long
|
|
load_PCB(struct pcb_struct *pcb)
|
|
{
|
|
register unsigned long sp __asm__("$30");
|
|
pcb->ksp = sp;
|
|
return __reload_thread(pcb);
|
|
}
|
|
|
|
/* Set up initial PCB, VPTB, and other such nicities. */
|
|
|
|
static inline void
|
|
switch_to_system_map(void)
|
|
{
|
|
unsigned long newptbr;
|
|
unsigned long original_pcb_ptr;
|
|
|
|
/* Initialize the kernel's page tables. Linux puts the vptb in
|
|
the last slot of the L1 page table. */
|
|
memset(swapper_pg_dir, 0, PAGE_SIZE);
|
|
newptbr = ((unsigned long) swapper_pg_dir - PAGE_OFFSET) >> PAGE_SHIFT;
|
|
pgd_val(swapper_pg_dir[1023]) =
|
|
(newptbr << 32) | pgprot_val(PAGE_KERNEL);
|
|
|
|
/* Set the vptb. This is often done by the bootloader, but
|
|
shouldn't be required. */
|
|
if (hwrpb->vptb != 0xfffffffe00000000UL) {
|
|
wrvptptr(0xfffffffe00000000UL);
|
|
hwrpb->vptb = 0xfffffffe00000000UL;
|
|
hwrpb_update_checksum(hwrpb);
|
|
}
|
|
|
|
/* Also set up the real kernel PCB while we're at it. */
|
|
init_thread_info.pcb.ptbr = newptbr;
|
|
init_thread_info.pcb.flags = 1; /* set FEN, clear everything else */
|
|
original_pcb_ptr = load_PCB(&init_thread_info.pcb);
|
|
tbia();
|
|
|
|
/* Save off the contents of the original PCB so that we can
|
|
restore the original console's page tables for a clean reboot.
|
|
|
|
Note that the PCB is supposed to be a physical address, but
|
|
since KSEG values also happen to work, folks get confused.
|
|
Check this here. */
|
|
|
|
if (original_pcb_ptr < PAGE_OFFSET) {
|
|
original_pcb_ptr = (unsigned long)
|
|
phys_to_virt(original_pcb_ptr);
|
|
}
|
|
original_pcb = *(struct pcb_struct *) original_pcb_ptr;
|
|
}
|
|
|
|
int callback_init_done;
|
|
|
|
void * __init
|
|
callback_init(void * kernel_end)
|
|
{
|
|
struct crb_struct * crb;
|
|
pgd_t *pgd;
|
|
pmd_t *pmd;
|
|
void *two_pages;
|
|
|
|
/* Starting at the HWRPB, locate the CRB. */
|
|
crb = (struct crb_struct *)((char *)hwrpb + hwrpb->crb_offset);
|
|
|
|
if (alpha_using_srm) {
|
|
/* Tell the console whither it is to be remapped. */
|
|
if (srm_fixup(VMALLOC_START, (unsigned long)hwrpb))
|
|
__halt(); /* "We're boned." --Bender */
|
|
|
|
/* Edit the procedure descriptors for DISPATCH and FIXUP. */
|
|
crb->dispatch_va = (struct procdesc_struct *)
|
|
(VMALLOC_START + (unsigned long)crb->dispatch_va
|
|
- crb->map[0].va);
|
|
crb->fixup_va = (struct procdesc_struct *)
|
|
(VMALLOC_START + (unsigned long)crb->fixup_va
|
|
- crb->map[0].va);
|
|
}
|
|
|
|
switch_to_system_map();
|
|
|
|
/* Allocate one PGD and one PMD. In the case of SRM, we'll need
|
|
these to actually remap the console. There is an assumption
|
|
here that only one of each is needed, and this allows for 8MB.
|
|
On systems with larger consoles, additional pages will be
|
|
allocated as needed during the mapping process.
|
|
|
|
In the case of not SRM, but not CONFIG_ALPHA_LARGE_VMALLOC,
|
|
we need to allocate the PGD we use for vmalloc before we start
|
|
forking other tasks. */
|
|
|
|
two_pages = (void *)
|
|
(((unsigned long)kernel_end + ~PAGE_MASK) & PAGE_MASK);
|
|
kernel_end = two_pages + 2*PAGE_SIZE;
|
|
memset(two_pages, 0, 2*PAGE_SIZE);
|
|
|
|
pgd = pgd_offset_k(VMALLOC_START);
|
|
pgd_set(pgd, (pmd_t *)two_pages);
|
|
pmd = pmd_offset(pgd, VMALLOC_START);
|
|
pmd_set(pmd, (pte_t *)(two_pages + PAGE_SIZE));
|
|
|
|
if (alpha_using_srm) {
|
|
static struct vm_struct console_remap_vm;
|
|
unsigned long nr_pages = 0;
|
|
unsigned long vaddr;
|
|
unsigned long i, j;
|
|
|
|
/* calculate needed size */
|
|
for (i = 0; i < crb->map_entries; ++i)
|
|
nr_pages += crb->map[i].count;
|
|
|
|
/* register the vm area */
|
|
console_remap_vm.flags = VM_ALLOC;
|
|
console_remap_vm.size = nr_pages << PAGE_SHIFT;
|
|
vm_area_register_early(&console_remap_vm, PAGE_SIZE);
|
|
|
|
vaddr = (unsigned long)console_remap_vm.addr;
|
|
|
|
/* Set up the third level PTEs and update the virtual
|
|
addresses of the CRB entries. */
|
|
for (i = 0; i < crb->map_entries; ++i) {
|
|
unsigned long pfn = crb->map[i].pa >> PAGE_SHIFT;
|
|
crb->map[i].va = vaddr;
|
|
for (j = 0; j < crb->map[i].count; ++j) {
|
|
/* Newer consoles (especially on larger
|
|
systems) may require more pages of
|
|
PTEs. Grab additional pages as needed. */
|
|
if (pmd != pmd_offset(pgd, vaddr)) {
|
|
memset(kernel_end, 0, PAGE_SIZE);
|
|
pmd = pmd_offset(pgd, vaddr);
|
|
pmd_set(pmd, (pte_t *)kernel_end);
|
|
kernel_end += PAGE_SIZE;
|
|
}
|
|
set_pte(pte_offset_kernel(pmd, vaddr),
|
|
pfn_pte(pfn, PAGE_KERNEL));
|
|
pfn++;
|
|
vaddr += PAGE_SIZE;
|
|
}
|
|
}
|
|
}
|
|
|
|
callback_init_done = 1;
|
|
return kernel_end;
|
|
}
|
|
|
|
|
|
#ifndef CONFIG_DISCONTIGMEM
|
|
/*
|
|
* paging_init() sets up the memory map.
|
|
*/
|
|
void __init paging_init(void)
|
|
{
|
|
unsigned long zones_size[MAX_NR_ZONES] = {0, };
|
|
unsigned long dma_pfn, high_pfn;
|
|
|
|
dma_pfn = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
|
|
high_pfn = max_pfn = max_low_pfn;
|
|
|
|
if (dma_pfn >= high_pfn)
|
|
zones_size[ZONE_DMA] = high_pfn;
|
|
else {
|
|
zones_size[ZONE_DMA] = dma_pfn;
|
|
zones_size[ZONE_NORMAL] = high_pfn - dma_pfn;
|
|
}
|
|
|
|
/* Initialize mem_map[]. */
|
|
free_area_init(zones_size);
|
|
|
|
/* Initialize the kernel's ZERO_PGE. */
|
|
memset((void *)ZERO_PGE, 0, PAGE_SIZE);
|
|
}
|
|
#endif /* CONFIG_DISCONTIGMEM */
|
|
|
|
#if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_SRM)
|
|
void
|
|
srm_paging_stop (void)
|
|
{
|
|
/* Move the vptb back to where the SRM console expects it. */
|
|
swapper_pg_dir[1] = swapper_pg_dir[1023];
|
|
tbia();
|
|
wrvptptr(0x200000000UL);
|
|
hwrpb->vptb = 0x200000000UL;
|
|
hwrpb_update_checksum(hwrpb);
|
|
|
|
/* Reload the page tables that the console had in use. */
|
|
load_PCB(&original_pcb);
|
|
tbia();
|
|
}
|
|
#endif
|
|
|
|
void __init
|
|
mem_init(void)
|
|
{
|
|
set_max_mapnr(max_low_pfn);
|
|
high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
|
|
free_all_bootmem();
|
|
mem_init_print_info(NULL);
|
|
}
|
|
|
|
void
|
|
free_initmem(void)
|
|
{
|
|
free_initmem_default(-1);
|
|
}
|
|
|
|
#ifdef CONFIG_BLK_DEV_INITRD
|
|
void
|
|
free_initrd_mem(unsigned long start, unsigned long end)
|
|
{
|
|
free_reserved_area((void *)start, (void *)end, -1, "initrd");
|
|
}
|
|
#endif
|