linuxdebug/arch/m68k/mm/sun3mmu.c

118 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/arch/m68k/mm/sun3mmu.c
*
* Implementations of mm routines specific to the sun3 MMU.
*
* Moved here 8/20/1999 Sam Creasey
*
*/
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/memblock.h>
#include <asm/setup.h>
#include <linux/uaccess.h>
#include <asm/page.h>
#include <asm/machdep.h>
#include <asm/io.h>
extern void mmu_emu_init (unsigned long bootmem_end);
const char bad_pmd_string[] = "Bad pmd in pte_alloc: %08lx\n";
extern unsigned long num_pages;
/* For the sun3 we try to follow the i386 paging_init() more closely */
/* start_mem and end_mem have PAGE_OFFSET added already */
/* now sets up tables using sun3 PTEs rather than i386 as before. --m */
void __init paging_init(void)
{
pgd_t * pg_dir;
pte_t * pg_table;
int i;
unsigned long address;
unsigned long next_pgtable;
unsigned long bootmem_end;
unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, };
unsigned long size;
empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
if (!empty_zero_page)
panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
__func__, PAGE_SIZE, PAGE_SIZE);
address = PAGE_OFFSET;
pg_dir = swapper_pg_dir;
memset (swapper_pg_dir, 0, sizeof (swapper_pg_dir));
memset (kernel_pg_dir, 0, sizeof (kernel_pg_dir));
size = num_pages * sizeof(pte_t);
size = (size + PAGE_SIZE) & ~(PAGE_SIZE-1);
next_pgtable = (unsigned long)memblock_alloc(size, PAGE_SIZE);
if (!next_pgtable)
panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
__func__, size, PAGE_SIZE);
bootmem_end = (next_pgtable + size + PAGE_SIZE) & PAGE_MASK;
/* Map whole memory from PAGE_OFFSET (0x0E000000) */
pg_dir += PAGE_OFFSET >> PGDIR_SHIFT;
while (address < (unsigned long)high_memory) {
pg_table = (pte_t *) __pa (next_pgtable);
next_pgtable += PTRS_PER_PTE * sizeof (pte_t);
pgd_val(*pg_dir) = (unsigned long) pg_table;
pg_dir++;
/* now change pg_table to kernel virtual addresses */
pg_table = (pte_t *) __va ((unsigned long) pg_table);
for (i=0; i<PTRS_PER_PTE; ++i, ++pg_table) {
pte_t pte = pfn_pte(virt_to_pfn(address), PAGE_INIT);
if (address >= (unsigned long)high_memory)
pte_val (pte) = 0;
set_pte (pg_table, pte);
address += PAGE_SIZE;
}
}
mmu_emu_init(bootmem_end);
current->mm = NULL;
/* memory sizing is a hack stolen from motorola.c.. hope it works for us */
max_zone_pfn[ZONE_DMA] = ((unsigned long)high_memory) >> PAGE_SHIFT;
/* I really wish I knew why the following change made things better... -- Sam */
free_area_init(max_zone_pfn);
}
static const pgprot_t protection_map[16] = {
[VM_NONE] = PAGE_NONE,
[VM_READ] = PAGE_READONLY,
[VM_WRITE] = PAGE_COPY,
[VM_WRITE | VM_READ] = PAGE_COPY,
[VM_EXEC] = PAGE_READONLY,
[VM_EXEC | VM_READ] = PAGE_READONLY,
[VM_EXEC | VM_WRITE] = PAGE_COPY,
[VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY,
[VM_SHARED] = PAGE_NONE,
[VM_SHARED | VM_READ] = PAGE_READONLY,
[VM_SHARED | VM_WRITE] = PAGE_SHARED,
[VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
[VM_SHARED | VM_EXEC] = PAGE_READONLY,
[VM_SHARED | VM_EXEC | VM_READ] = PAGE_READONLY,
[VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED,
[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED
};
DECLARE_VM_GET_PAGE_PROT