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

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C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1994 - 2000 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
* Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
* Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
*/
#include <linux/bug.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/pagemap.h>
#include <linux/ptrace.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/highmem.h>
#include <linux/swap.h>
#include <linux/proc_fs.h>
#include <linux/pfn.h>
#include <linux/hardirq.h>
#include <linux/gfp.h>
#include <asm/asm-offsets.h>
#include <asm/bootinfo.h>
#include <asm/cachectl.h>
#include <asm/cpu.h>
#include <asm/dma.h>
#include <asm/kmap_types.h>
#include <asm/mmu_context.h>
#include <asm/sections.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/tlb.h>
#include <asm/fixmap.h>
/* Atomicity and interruptability */
#ifdef CONFIG_MIPS_MT_SMTC
#include <asm/mipsmtregs.h>
#define ENTER_CRITICAL(flags) \
{ \
unsigned int mvpflags; \
local_irq_save(flags);\
mvpflags = dvpe()
#define EXIT_CRITICAL(flags) \
evpe(mvpflags); \
local_irq_restore(flags); \
}
#else
#define ENTER_CRITICAL(flags) local_irq_save(flags)
#define EXIT_CRITICAL(flags) local_irq_restore(flags)
#endif /* CONFIG_MIPS_MT_SMTC */
DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
/*
* We have up to 8 empty zeroed pages so we can map one of the right colour
* when needed. This is necessary only on R4000 / R4400 SC and MC versions
* where we have to avoid VCED / VECI exceptions for good performance at
* any price. Since page is never written to after the initialization we
* don't have to care about aliases on other CPUs.
*/
unsigned long empty_zero_page, zero_page_mask;
EXPORT_SYMBOL_GPL(empty_zero_page);
/*
* Not static inline because used by IP27 special magic initialization code
*/
unsigned long setup_zero_pages(void)
{
unsigned int order;
unsigned long size;
struct page *page;
if (cpu_has_vce)
order = 3;
else
order = 0;
empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
if (!empty_zero_page)
panic("Oh boy, that early out of memory?");
page = virt_to_page((void *)empty_zero_page);
split_page(page, order);
while (page < virt_to_page((void *)(empty_zero_page + (PAGE_SIZE << order)))) {
SetPageReserved(page);
page++;
}
size = PAGE_SIZE << order;
zero_page_mask = (size - 1) & PAGE_MASK;
return 1UL << order;
}
#ifdef CONFIG_MIPS_MT_SMTC
static pte_t *kmap_coherent_pte;
static void __init kmap_coherent_init(void)
{
unsigned long vaddr;
/* cache the first coherent kmap pte */
vaddr = __fix_to_virt(FIX_CMAP_BEGIN);
kmap_coherent_pte = kmap_get_fixmap_pte(vaddr);
}
#else
static inline void kmap_coherent_init(void) {}
#endif
void *kmap_coherent(struct page *page, unsigned long addr)
{
enum fixed_addresses idx;
unsigned long vaddr, flags, entrylo;
unsigned long old_ctx;
pte_t pte;
int tlbidx;
BUG_ON(Page_dcache_dirty(page));
inc_preempt_count();
idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
#ifdef CONFIG_MIPS_MT_SMTC
idx += FIX_N_COLOURS * smp_processor_id() +
(in_interrupt() ? (FIX_N_COLOURS * NR_CPUS) : 0);
#else
idx += in_interrupt() ? FIX_N_COLOURS : 0;
#endif
vaddr = __fix_to_virt(FIX_CMAP_END - idx);
pte = mk_pte(page, PAGE_KERNEL);
#if defined(CONFIG_64BIT_PHYS_ADDR) && defined(CONFIG_CPU_MIPS32)
entrylo = pte.pte_high;
#else
entrylo = pte_to_entrylo(pte_val(pte));
#endif
ENTER_CRITICAL(flags);
old_ctx = read_c0_entryhi();
write_c0_entryhi(vaddr & (PAGE_MASK << 1));
write_c0_entrylo0(entrylo);
write_c0_entrylo1(entrylo);
#ifdef CONFIG_MIPS_MT_SMTC
set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte);
/* preload TLB instead of local_flush_tlb_one() */
mtc0_tlbw_hazard();
tlb_probe();
tlb_probe_hazard();
tlbidx = read_c0_index();
mtc0_tlbw_hazard();
if (tlbidx < 0)
tlb_write_random();
else
tlb_write_indexed();
#else
tlbidx = read_c0_wired();
write_c0_wired(tlbidx + 1);
write_c0_index(tlbidx);
mtc0_tlbw_hazard();
tlb_write_indexed();
#endif
tlbw_use_hazard();
write_c0_entryhi(old_ctx);
EXIT_CRITICAL(flags);
return (void*) vaddr;
}
#define UNIQUE_ENTRYHI(idx) (CKSEG0 + ((idx) << (PAGE_SHIFT + 1)))
void kunmap_coherent(void)
{
#ifndef CONFIG_MIPS_MT_SMTC
unsigned int wired;
unsigned long flags, old_ctx;
ENTER_CRITICAL(flags);
old_ctx = read_c0_entryhi();
wired = read_c0_wired() - 1;
write_c0_wired(wired);
write_c0_index(wired);
write_c0_entryhi(UNIQUE_ENTRYHI(wired));
write_c0_entrylo0(0);
write_c0_entrylo1(0);
mtc0_tlbw_hazard();
tlb_write_indexed();
tlbw_use_hazard();
write_c0_entryhi(old_ctx);
EXIT_CRITICAL(flags);
#endif
dec_preempt_count();
preempt_check_resched();
}
void copy_user_highpage(struct page *to, struct page *from,
unsigned long vaddr, struct vm_area_struct *vma)
{
void *vfrom, *vto;
vto = kmap_atomic(to, KM_USER1);
if (cpu_has_dc_aliases &&
page_mapped(from) && !Page_dcache_dirty(from)) {
vfrom = kmap_coherent(from, vaddr);
copy_page(vto, vfrom);
kunmap_coherent();
} else {
vfrom = kmap_atomic(from, KM_USER0);
copy_page(vto, vfrom);
kunmap_atomic(vfrom, KM_USER0);
}
if ((!cpu_has_ic_fills_f_dc) ||
pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
flush_data_cache_page((unsigned long)vto);
kunmap_atomic(vto, KM_USER1);
/* Make sure this page is cleared on other CPU's too before using it */
smp_wmb();
}
void copy_to_user_page(struct vm_area_struct *vma,
struct page *page, unsigned long vaddr, void *dst, const void *src,
unsigned long len)
{
if (cpu_has_dc_aliases &&
page_mapped(page) && !Page_dcache_dirty(page)) {
void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
memcpy(vto, src, len);
kunmap_coherent();
} else {
memcpy(dst, src, len);
if (cpu_has_dc_aliases)
SetPageDcacheDirty(page);
}
if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc)
flush_cache_page(vma, vaddr, page_to_pfn(page));
}
void copy_from_user_page(struct vm_area_struct *vma,
struct page *page, unsigned long vaddr, void *dst, const void *src,
unsigned long len)
{
if (cpu_has_dc_aliases &&
page_mapped(page) && !Page_dcache_dirty(page)) {
void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
memcpy(dst, vfrom, len);
kunmap_coherent();
} else {
memcpy(dst, src, len);
if (cpu_has_dc_aliases)
SetPageDcacheDirty(page);
}
}
void __init fixrange_init(unsigned long start, unsigned long end,
pgd_t *pgd_base)
{
#if defined(CONFIG_HIGHMEM) || defined(CONFIG_MIPS_MT_SMTC)
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
int i, j, k;
unsigned long vaddr;
vaddr = start;
i = __pgd_offset(vaddr);
j = __pud_offset(vaddr);
k = __pmd_offset(vaddr);
pgd = pgd_base + i;
for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
pud = (pud_t *)pgd;
for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
pmd = (pmd_t *)pud;
for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
if (pmd_none(*pmd)) {
pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
set_pmd(pmd, __pmd((unsigned long)pte));
BUG_ON(pte != pte_offset_kernel(pmd, 0));
}
vaddr += PMD_SIZE;
}
k = 0;
}
j = 0;
}
#endif
}
#ifndef CONFIG_NEED_MULTIPLE_NODES
int page_is_ram(unsigned long pagenr)
{
int i;
for (i = 0; i < boot_mem_map.nr_map; i++) {
unsigned long addr, end;
if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
/* not usable memory */
continue;
addr = PFN_UP(boot_mem_map.map[i].addr);
end = PFN_DOWN(boot_mem_map.map[i].addr +
boot_mem_map.map[i].size);
if (pagenr >= addr && pagenr < end)
return 1;
}
return 0;
}
void __init paging_init(void)
{
unsigned long max_zone_pfns[MAX_NR_ZONES];
unsigned long lastpfn;
pagetable_init();
#ifdef CONFIG_HIGHMEM
kmap_init();
#endif
kmap_coherent_init();
#ifdef CONFIG_ZONE_DMA
max_zone_pfns[ZONE_DMA] = MAX_DMA_PFN;
#endif
#ifdef CONFIG_ZONE_DMA32
max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
#endif
max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
lastpfn = max_low_pfn;
#ifdef CONFIG_HIGHMEM
max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
lastpfn = highend_pfn;
if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) {
printk(KERN_WARNING "This processor doesn't support highmem."
" %ldk highmem ignored\n",
(highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10));
max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn;
lastpfn = max_low_pfn;
}
#endif
free_area_init_nodes(max_zone_pfns);
}
#ifdef CONFIG_64BIT
static struct kcore_list kcore_kseg0;
#endif
void __init mem_init(void)
{
unsigned long codesize, reservedpages, datasize, initsize;
unsigned long tmp, ram;
#ifdef CONFIG_HIGHMEM
#ifdef CONFIG_DISCONTIGMEM
#error "CONFIG_HIGHMEM and CONFIG_DISCONTIGMEM dont work together yet"
#endif
max_mapnr = highend_pfn;
#else
max_mapnr = max_low_pfn;
#endif
high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
totalram_pages += free_all_bootmem();
totalram_pages -= setup_zero_pages(); /* Setup zeroed pages. */
reservedpages = ram = 0;
for (tmp = 0; tmp < max_low_pfn; tmp++)
if (page_is_ram(tmp)) {
ram++;
if (PageReserved(pfn_to_page(tmp)))
reservedpages++;
}
num_physpages = ram;
#ifdef CONFIG_HIGHMEM
for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
struct page *page = pfn_to_page(tmp);
if (!page_is_ram(tmp)) {
SetPageReserved(page);
continue;
}
ClearPageReserved(page);
init_page_count(page);
__free_page(page);
totalhigh_pages++;
}
totalram_pages += totalhigh_pages;
num_physpages += totalhigh_pages;
#endif
codesize = (unsigned long) &_etext - (unsigned long) &_text;
datasize = (unsigned long) &_edata - (unsigned long) &_etext;
initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
#ifdef CONFIG_64BIT
if ((unsigned long) &_text > (unsigned long) CKSEG0)
/* The -4 is a hack so that user tools don't have to handle
the overflow. */
kclist_add(&kcore_kseg0, (void *) CKSEG0,
0x80000000 - 4, KCORE_TEXT);
#endif
printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
"%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
nr_free_pages() << (PAGE_SHIFT-10),
ram << (PAGE_SHIFT-10),
codesize >> 10,
reservedpages << (PAGE_SHIFT-10),
datasize >> 10,
initsize >> 10,
totalhigh_pages << (PAGE_SHIFT-10));
}
#endif /* !CONFIG_NEED_MULTIPLE_NODES */
void free_init_pages(const char *what, unsigned long begin, unsigned long end)
{
unsigned long pfn;
for (pfn = PFN_UP(begin); pfn < PFN_DOWN(end); pfn++) {
struct page *page = pfn_to_page(pfn);
void *addr = phys_to_virt(PFN_PHYS(pfn));
ClearPageReserved(page);
init_page_count(page);
memset(addr, POISON_FREE_INITMEM, PAGE_SIZE);
__free_page(page);
totalram_pages++;
}
printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
}
#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
free_init_pages("initrd memory",
virt_to_phys((void *)start),
virt_to_phys((void *)end));
}
#endif
void __init_refok free_initmem(void)
{
prom_free_prom_memory();
free_init_pages("unused kernel memory",
__pa_symbol(&__init_begin),
__pa_symbol(&__init_end));
}
#ifndef CONFIG_MIPS_PGD_C0_CONTEXT
unsigned long pgd_current[NR_CPUS];
#endif
/*
* On 64-bit we've got three-level pagetables with a slightly
* different layout ...
*/
#define __page_aligned(order) __attribute__((__aligned__(PAGE_SIZE<<order)))
/*
* gcc 3.3 and older have trouble determining that PTRS_PER_PGD and PGD_ORDER
* are constants. So we use the variants from asm-offset.h until that gcc
* will officially be retired.
*/
pgd_t swapper_pg_dir[_PTRS_PER_PGD] __page_aligned(_PGD_ORDER);
#ifndef __PAGETABLE_PMD_FOLDED
pmd_t invalid_pmd_table[PTRS_PER_PMD] __page_aligned(PMD_ORDER);
#endif
pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER);