arch/mips/mm/init.c - kernel/msm-4.9 - Gitiles

 /*
  * 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/init.h>
 #include <linux/module.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/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 <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);

 unsigned long highstart_pfn, highend_pfn;

 /*
  * 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;

 /*
  * 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;
 }

 /*
  * These are almost like kmap_atomic / kunmap_atmic except they take an
  * additional address argument as the hint.
  */

 #define kmap_get_fixmap_pte(vaddr)					\
 	pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr))

 #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

 static inline 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;

 	inc_preempt_count();
 	idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
 #ifdef CONFIG_MIPS_MT_SMTC
 	idx += FIX_N_COLOURS * smp_processor_id();
 #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_R1)
 	entrylo = pte.pte_high;
 #else
 	entrylo = pte_val(pte) >> 6;
 #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)))

 static inline void kunmap_coherent(struct page *page)
 {
 #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_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) {
 		void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
 		memcpy(vto, src, len);
 		kunmap_coherent(page);
 	} else
 		memcpy(dst, src, len);
 	if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc)
 		flush_cache_page(vma, vaddr, page_to_pfn(page));
 }

 EXPORT_SYMBOL(copy_to_user_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) {
 		void *vfrom =
 			kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
 		memcpy(dst, vfrom, len);
 		kunmap_coherent(page);
 	} else
 		memcpy(dst, src, len);
 }

 EXPORT_SYMBOL(copy_from_user_page);


 #ifdef CONFIG_HIGHMEM
 pte_t *kmap_pte;
 pgprot_t kmap_prot;

 static void __init kmap_init(void)
 {
 	unsigned long kmap_vstart;

 	/* cache the first kmap pte */
 	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
 	kmap_pte = kmap_get_fixmap_pte(kmap_vstart);

 	kmap_prot = PAGE_KERNEL;
 }
 #endif /* CONFIG_HIGHMEM */

 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));
 					if (pte != pte_offset_kernel(pmd, 0))
 						BUG();
 				}
 				vaddr += PMD_SIZE;
 			}
 			k = 0;
 		}
 		j = 0;
 	}
 #endif
 }

 #ifndef CONFIG_NEED_MULTIPLE_NODES
 extern void pagetable_init(void);

 static int __init 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 zones_size[MAX_NR_ZONES] = { 0, };
 	unsigned long max_dma, high, low;
 #ifndef CONFIG_FLATMEM
 	unsigned long zholes_size[MAX_NR_ZONES] = { 0, };
 	unsigned long i, j, pfn;
 #endif

 	pagetable_init();

 #ifdef CONFIG_HIGHMEM
 	kmap_init();
 #endif
 	kmap_coherent_init();

 	max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
 	low = max_low_pfn;
 	high = highend_pfn;

 #ifdef CONFIG_ISA
 	if (low < max_dma)
 		zones_size[ZONE_DMA] = low;
 	else {
 		zones_size[ZONE_DMA] = max_dma;
 		zones_size[ZONE_NORMAL] = low - max_dma;
 	}
 #else
 	zones_size[ZONE_DMA] = low;
 #endif
 #ifdef CONFIG_HIGHMEM
 	if (cpu_has_dc_aliases) {
 		printk(KERN_WARNING "This processor doesn't support highmem.");
 		if (high - low)
 			printk(" %ldk highmem ignored", high - low);
 		printk("\n");
 	} else
 		zones_size[ZONE_HIGHMEM] = high - low;
 #endif

 #ifdef CONFIG_FLATMEM
 	free_area_init(zones_size);
 #else
 	pfn = 0;
 	for (i = 0; i < MAX_NR_ZONES; i++)
 		for (j = 0; j < zones_size[i]; j++, pfn++)
 			if (!page_is_ram(pfn))
 				zholes_size[i]++;
 	free_area_init_node(0, NODE_DATA(0), zones_size, 0, zholes_size);
 #endif
 }

 static struct kcore_list kcore_mem, kcore_vmalloc;
 #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 = mem_map + tmp;

 		if (!page_is_ram(tmp)) {
 			SetPageReserved(page);
 			continue;
 		}
 		ClearPageReserved(page);
 #ifdef CONFIG_LIMITED_DMA
 		set_page_address(page, lowmem_page_address(page));
 #endif
 		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);
 #endif
 	kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
 	kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
 		   VMALLOC_END-VMALLOC_START);

 	printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
 	       "%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
 	       (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 	       ram << (PAGE_SHIFT-10),
 	       codesize >> 10,
 	       reservedpages << (PAGE_SHIFT-10),
 	       datasize >> 10,
 	       initsize >> 10,
 	       (unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
 }
 #endif /* !CONFIG_NEED_MULTIPLE_NODES */

 static void free_init_pages(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

 extern unsigned long prom_free_prom_memory(void);

 void free_initmem(void)
 {
 	unsigned long freed;

 	freed = prom_free_prom_memory();
 	if (freed)
 		printk(KERN_INFO "Freeing firmware memory: %ldk freed\n",freed);

 	free_init_pages("unused kernel memory",
 			__pa_symbol(&__init_begin),
 			__pa_symbol(&__init_end));
 }
	/*
	* 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/init.h>
	#include <linux/module.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/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 <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);

	unsigned long highstart_pfn, highend_pfn;

	/*
	* 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;

	/*
	* 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;
	}

	/*
	* These are almost like kmap_atomic / kunmap_atmic except they take an
	* additional address argument as the hint.
	*/

	#define kmap_get_fixmap_pte(vaddr) \
	pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr))

	#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

	static inline 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;

	inc_preempt_count();
	idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1);
	#ifdef CONFIG_MIPS_MT_SMTC
	idx += FIX_N_COLOURS * smp_processor_id();
	#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_R1)
	entrylo = pte.pte_high;
	#else
	entrylo = pte_val(pte) >> 6;
	#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)))

	static inline void kunmap_coherent(struct page *page)
	{
	#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_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) {
	void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
	memcpy(vto, src, len);
	kunmap_coherent(page);
	} else
	memcpy(dst, src, len);
	if ((vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc)
	flush_cache_page(vma, vaddr, page_to_pfn(page));
	}

	EXPORT_SYMBOL(copy_to_user_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) {
	void *vfrom =
	kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK);
	memcpy(dst, vfrom, len);
	kunmap_coherent(page);
	} else
	memcpy(dst, src, len);
	}

	EXPORT_SYMBOL(copy_from_user_page);


	#ifdef CONFIG_HIGHMEM
	pte_t *kmap_pte;
	pgprot_t kmap_prot;

	static void __init kmap_init(void)
	{
	unsigned long kmap_vstart;

	/* cache the first kmap pte */
	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
	kmap_pte = kmap_get_fixmap_pte(kmap_vstart);

	kmap_prot = PAGE_KERNEL;
	}
	#endif /* CONFIG_HIGHMEM */

	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));
	if (pte != pte_offset_kernel(pmd, 0))
	BUG();
	}
	vaddr += PMD_SIZE;
	}
	k = 0;
	}
	j = 0;
	}
	#endif
	}

	#ifndef CONFIG_NEED_MULTIPLE_NODES
	extern void pagetable_init(void);

	static int __init 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 zones_size[MAX_NR_ZONES] = { 0, };
	unsigned long max_dma, high, low;
	#ifndef CONFIG_FLATMEM
	unsigned long zholes_size[MAX_NR_ZONES] = { 0, };
	unsigned long i, j, pfn;
	#endif

	pagetable_init();

	#ifdef CONFIG_HIGHMEM
	kmap_init();
	#endif
	kmap_coherent_init();

	max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
	low = max_low_pfn;
	high = highend_pfn;

	#ifdef CONFIG_ISA
	if (low < max_dma)
	zones_size[ZONE_DMA] = low;
	else {
	zones_size[ZONE_DMA] = max_dma;
	zones_size[ZONE_NORMAL] = low - max_dma;
	}
	#else
	zones_size[ZONE_DMA] = low;
	#endif
	#ifdef CONFIG_HIGHMEM
	if (cpu_has_dc_aliases) {
	printk(KERN_WARNING "This processor doesn't support highmem.");
	if (high - low)
	printk(" %ldk highmem ignored", high - low);
	printk("\n");
	} else
	zones_size[ZONE_HIGHMEM] = high - low;
	#endif

	#ifdef CONFIG_FLATMEM
	free_area_init(zones_size);
	#else
	pfn = 0;
	for (i = 0; i < MAX_NR_ZONES; i++)
	for (j = 0; j < zones_size[i]; j++, pfn++)
	if (!page_is_ram(pfn))
	zholes_size[i]++;
	free_area_init_node(0, NODE_DATA(0), zones_size, 0, zholes_size);
	#endif
	}

	static struct kcore_list kcore_mem, kcore_vmalloc;
	#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 = mem_map + tmp;

	if (!page_is_ram(tmp)) {
	SetPageReserved(page);
	continue;
	}
	ClearPageReserved(page);
	#ifdef CONFIG_LIMITED_DMA
	set_page_address(page, lowmem_page_address(page));
	#endif
	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);
	#endif
	kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
	kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
	VMALLOC_END-VMALLOC_START);

	printk(KERN_INFO "Memory: %luk/%luk available (%ldk kernel code, "
	"%ldk reserved, %ldk data, %ldk init, %ldk highmem)\n",
	(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
	ram << (PAGE_SHIFT-10),
	codesize >> 10,
	reservedpages << (PAGE_SHIFT-10),
	datasize >> 10,
	initsize >> 10,
	(unsigned long) (totalhigh_pages << (PAGE_SHIFT-10)));
	}
	#endif /* !CONFIG_NEED_MULTIPLE_NODES */

	static void free_init_pages(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

	extern unsigned long prom_free_prom_memory(void);

	void free_initmem(void)
	{
	unsigned long freed;

	freed = prom_free_prom_memory();
	if (freed)
	printk(KERN_INFO "Freeing firmware memory: %ldk freed\n",freed);

	free_init_pages("unused kernel memory",
	__pa_symbol(&__init_begin),
	__pa_symbol(&__init_end));
	}