[deliverable/linux.git] / arch / powerpc / mm / pgtable_32.c

/*
 * This file contains the routines setting up the linux page tables.
 *  -- paulus
 *
 *  Derived from arch/ppc/mm/init.c:
 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
 *
 *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
 *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
 *    Copyright (C) 1996 Paul Mackerras
 *
 *  Derived from "arch/i386/mm/init.c"
 *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version
 *  2 of the License, or (at your option) any later version.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
#include <linux/highmem.h>
#include <linux/lmb.h>
#include <linux/slab.h>

#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/fixmap.h>
#include <asm/io.h>

#include "mmu_decl.h"

unsigned long ioremap_base;
unsigned long ioremap_bot;
EXPORT_SYMBOL(ioremap_bot);	/* aka VMALLOC_END */

#if defined(CONFIG_6xx) || defined(CONFIG_POWER3)
#define HAVE_BATS	1
#endif

#if defined(CONFIG_FSL_BOOKE)
#define HAVE_TLBCAM	1
#endif

extern char etext[], _stext[];

#ifdef HAVE_BATS
extern phys_addr_t v_mapped_by_bats(unsigned long va);
extern unsigned long p_mapped_by_bats(phys_addr_t pa);
void setbat(int index, unsigned long virt, phys_addr_t phys,
	    unsigned int size, int flags);

#else /* !HAVE_BATS */
#define v_mapped_by_bats(x)	(0UL)
#define p_mapped_by_bats(x)	(0UL)
#endif /* HAVE_BATS */

#ifdef HAVE_TLBCAM
extern unsigned int tlbcam_index;
extern phys_addr_t v_mapped_by_tlbcam(unsigned long va);
extern unsigned long p_mapped_by_tlbcam(phys_addr_t pa);
#else /* !HAVE_TLBCAM */
#define v_mapped_by_tlbcam(x)	(0UL)
#define p_mapped_by_tlbcam(x)	(0UL)
#endif /* HAVE_TLBCAM */

#define PGDIR_ORDER	(32 + PGD_T_LOG2 - PGDIR_SHIFT)

pgd_t *pgd_alloc(struct mm_struct *mm)
{
	pgd_t *ret;

	/* pgdir take page or two with 4K pages and a page fraction otherwise */
#ifndef CONFIG_PPC_4K_PAGES
	ret = (pgd_t *)kzalloc(1 << PGDIR_ORDER, GFP_KERNEL);
#else
	ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
			PGDIR_ORDER - PAGE_SHIFT);
#endif
	return ret;
}

void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
#ifndef CONFIG_PPC_4K_PAGES
	kfree((void *)pgd);
#else
	free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT);
#endif
}

__init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
{
	pte_t *pte;
	extern int mem_init_done;
	extern void *early_get_page(void);

	if (mem_init_done) {
		pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
	} else {
		pte = (pte_t *)early_get_page();
		if (pte)
			clear_page(pte);
	}
	return pte;
}

pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
{
	struct page *ptepage;

	gfp_t flags = GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO;

	ptepage = alloc_pages(flags, 0);
	if (!ptepage)
		return NULL;
	pgtable_page_ctor(ptepage);
	return ptepage;
}

void __iomem *
ioremap(phys_addr_t addr, unsigned long size)
{
	return __ioremap_caller(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED,
				__builtin_return_address(0));
}
EXPORT_SYMBOL(ioremap);

void __iomem *
ioremap_flags(phys_addr_t addr, unsigned long size, unsigned long flags)
{
	/* writeable implies dirty for kernel addresses */
	if (flags & _PAGE_RW)
		flags |= _PAGE_DIRTY | _PAGE_HWWRITE;

	/* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
	flags &= ~(_PAGE_USER | _PAGE_EXEC);

#ifdef _PAGE_BAP_SR
	/* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format
	 * which means that we just cleared supervisor access... oops ;-) This
	 * restores it
	 */
	flags |= _PAGE_BAP_SR;
#endif

	return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
}
EXPORT_SYMBOL(ioremap_flags);

void __iomem *
__ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
{
	return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
}

void __iomem *
__ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
		 void *caller)
{
	unsigned long v, i;
	phys_addr_t p;
	int err;

	/* Make sure we have the base flags */
	if ((flags & _PAGE_PRESENT) == 0)
		flags |= PAGE_KERNEL;

	/* Non-cacheable page cannot be coherent */
	if (flags & _PAGE_NO_CACHE)
		flags &= ~_PAGE_COHERENT;

	/*
	 * Choose an address to map it to.
	 * Once the vmalloc system is running, we use it.
	 * Before then, we use space going down from ioremap_base
	 * (ioremap_bot records where we're up to).
	 */
	p = addr & PAGE_MASK;
	size = PAGE_ALIGN(addr + size) - p;

	/*
	 * If the address lies within the first 16 MB, assume it's in ISA
	 * memory space
	 */
	if (p < 16*1024*1024)
		p += _ISA_MEM_BASE;

#ifndef CONFIG_CRASH_DUMP
	/*
	 * Don't allow anybody to remap normal RAM that we're using.
	 * mem_init() sets high_memory so only do the check after that.
	 */
	if (mem_init_done && (p < virt_to_phys(high_memory)) &&
	    !(__allow_ioremap_reserved && lmb_is_region_reserved(p, size))) {
		printk("__ioremap(): phys addr 0x%llx is RAM lr %p\n",
		       (unsigned long long)p, __builtin_return_address(0));
		return NULL;
	}
#endif

	if (size == 0)
		return NULL;

	/*
	 * Is it already mapped?  Perhaps overlapped by a previous
	 * BAT mapping.  If the whole area is mapped then we're done,
	 * otherwise remap it since we want to keep the virt addrs for
	 * each request contiguous.
	 *
	 * We make the assumption here that if the bottom and top
	 * of the range we want are mapped then it's mapped to the
	 * same virt address (and this is contiguous).
	 *  -- Cort
	 */
	if ((v = p_mapped_by_bats(p)) /*&& p_mapped_by_bats(p+size-1)*/ )
		goto out;

	if ((v = p_mapped_by_tlbcam(p)))
		goto out;

	if (mem_init_done) {
		struct vm_struct *area;
		area = get_vm_area_caller(size, VM_IOREMAP, caller);
		if (area == 0)
			return NULL;
		v = (unsigned long) area->addr;
	} else {
		v = (ioremap_bot -= size);
	}

	/*
	 * Should check if it is a candidate for a BAT mapping
	 */

	err = 0;
	for (i = 0; i < size && err == 0; i += PAGE_SIZE)
		err = map_page(v+i, p+i, flags);
	if (err) {
		if (mem_init_done)
			vunmap((void *)v);
		return NULL;
	}

out:
	return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
}
EXPORT_SYMBOL(__ioremap);

void iounmap(volatile void __iomem *addr)
{
	/*
	 * If mapped by BATs then there is nothing to do.
	 * Calling vfree() generates a benign warning.
	 */
	if (v_mapped_by_bats((unsigned long)addr)) return;

	if (addr > high_memory && (unsigned long) addr < ioremap_bot)
		vunmap((void *) (PAGE_MASK & (unsigned long)addr));
}
EXPORT_SYMBOL(iounmap);

int map_page(unsigned long va, phys_addr_t pa, int flags)
{
	pmd_t *pd;
	pte_t *pg;
	int err = -ENOMEM;

	/* Use upper 10 bits of VA to index the first level map */
	pd = pmd_offset(pud_offset(pgd_offset_k(va), va), va);
	/* Use middle 10 bits of VA to index the second-level map */
	pg = pte_alloc_kernel(pd, va);
	if (pg != 0) {
		err = 0;
		/* The PTE should never be already set nor present in the
		 * hash table
		 */
		BUG_ON((pte_val(*pg) & (_PAGE_PRESENT | _PAGE_HASHPTE)) &&
		       flags);
		set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
						     __pgprot(flags)));
	}
	return err;
}

/*
 * Map in a chunk of physical memory starting at start.
 */
void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
{
	unsigned long v, s, f;
	phys_addr_t p;
	int ktext;

	s = offset;
	v = PAGE_OFFSET + s;
	p = memstart_addr + s;
	for (; s < top; s += PAGE_SIZE) {
		ktext = ((char *) v >= _stext && (char *) v < etext);
		f = ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL;
		map_page(v, p, f);
#ifdef CONFIG_PPC_STD_MMU_32
		if (ktext)
			hash_preload(&init_mm, v, 0, 0x300);
#endif
		v += PAGE_SIZE;
		p += PAGE_SIZE;
	}
}

void __init mapin_ram(void)
{
	unsigned long s, top;

#ifndef CONFIG_WII
	top = total_lowmem;
	s = mmu_mapin_ram(top);
	__mapin_ram_chunk(s, top);
#else
	if (!wii_hole_size) {
		s = mmu_mapin_ram(total_lowmem);
		__mapin_ram_chunk(s, total_lowmem);
	} else {
		top = wii_hole_start;
		s = mmu_mapin_ram(top);
		__mapin_ram_chunk(s, top);

		top = lmb_end_of_DRAM();
		s = wii_mmu_mapin_mem2(top);
		__mapin_ram_chunk(s, top);
	}
#endif
}

/* Scan the real Linux page tables and return a PTE pointer for
 * a virtual address in a context.
 * Returns true (1) if PTE was found, zero otherwise.  The pointer to
 * the PTE pointer is unmodified if PTE is not found.
 */
int
get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep, pmd_t **pmdp)
{
        pgd_t	*pgd;
	pud_t	*pud;
        pmd_t	*pmd;
        pte_t	*pte;
        int     retval = 0;

        pgd = pgd_offset(mm, addr & PAGE_MASK);
        if (pgd) {
		pud = pud_offset(pgd, addr & PAGE_MASK);
		if (pud && pud_present(*pud)) {
			pmd = pmd_offset(pud, addr & PAGE_MASK);
			if (pmd_present(*pmd)) {
				pte = pte_offset_map(pmd, addr & PAGE_MASK);
				if (pte) {
					retval = 1;
					*ptep = pte;
					if (pmdp)
						*pmdp = pmd;
					/* XXX caller needs to do pte_unmap, yuck */
				}
			}
		}
        }
        return(retval);
}

#ifdef CONFIG_DEBUG_PAGEALLOC

static int __change_page_attr(struct page *page, pgprot_t prot)
{
	pte_t *kpte;
	pmd_t *kpmd;
	unsigned long address;

	BUG_ON(PageHighMem(page));
	address = (unsigned long)page_address(page);

	if (v_mapped_by_bats(address) || v_mapped_by_tlbcam(address))
		return 0;
	if (!get_pteptr(&init_mm, address, &kpte, &kpmd))
		return -EINVAL;
	__set_pte_at(&init_mm, address, kpte, mk_pte(page, prot), 0);
	wmb();
	flush_tlb_page(NULL, address);
	pte_unmap(kpte);

	return 0;
}

/*
 * Change the page attributes of an page in the linear mapping.
 *
 * THIS CONFLICTS WITH BAT MAPPINGS, DEBUG USE ONLY
 */
static int change_page_attr(struct page *page, int numpages, pgprot_t prot)
{
	int i, err = 0;
	unsigned long flags;

	local_irq_save(flags);
	for (i = 0; i < numpages; i++, page++) {
		err = __change_page_attr(page, prot);
		if (err)
			break;
	}
	local_irq_restore(flags);
	return err;
}


void kernel_map_pages(struct page *page, int numpages, int enable)
{
	if (PageHighMem(page))
		return;

	change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
}
#endif /* CONFIG_DEBUG_PAGEALLOC */

static int fixmaps;

void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
{
	unsigned long address = __fix_to_virt(idx);

	if (idx >= __end_of_fixed_addresses) {
		BUG();
		return;
	}

	map_page(address, phys, pgprot_val(flags));
	fixmaps++;
}

void __this_fixmap_does_not_exist(void)
{
	WARN_ON(1);
}
Commit	Line	Data
	1	/*
	2	* This file contains the routines setting up the linux page tables.
	3	* -- paulus
	4	*
	5	* Derived from arch/ppc/mm/init.c:
	6	* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
	7	*
	8	* Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
	9	* and Cort Dougan (PReP) (cort@cs.nmt.edu)
	10	* Copyright (C) 1996 Paul Mackerras
	11	*
	12	* Derived from "arch/i386/mm/init.c"
	13	* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
	14	*
	15	* This program is free software; you can redistribute it and/or
	16	* modify it under the terms of the GNU General Public License
	17	* as published by the Free Software Foundation; either version
	18	* 2 of the License, or (at your option) any later version.
	19	*
	20	*/
	21
	22	#include <linux/kernel.h>
	23	#include <linux/module.h>
	24	#include <linux/types.h>
	25	#include <linux/mm.h>
	26	#include <linux/vmalloc.h>
	27	#include <linux/init.h>
	28	#include <linux/highmem.h>
	29	#include <linux/lmb.h>
	30	#include <linux/slab.h>
	31
	32	#include <asm/pgtable.h>
	33	#include <asm/pgalloc.h>
	34	#include <asm/fixmap.h>
	35	#include <asm/io.h>
	36
	37	#include "mmu_decl.h"
	38
	39	unsigned long ioremap_base;
	40	unsigned long ioremap_bot;
	41	EXPORT_SYMBOL(ioremap_bot); /* aka VMALLOC_END */
	42
	43	#if defined(CONFIG_6xx) \|\| defined(CONFIG_POWER3)
	44	#define HAVE_BATS 1
	45	#endif
	46
	47	#if defined(CONFIG_FSL_BOOKE)
	48	#define HAVE_TLBCAM 1
	49	#endif
	50
	51	extern char etext[], _stext[];
	52
	53	#ifdef HAVE_BATS
	54	extern phys_addr_t v_mapped_by_bats(unsigned long va);
	55	extern unsigned long p_mapped_by_bats(phys_addr_t pa);
	56	void setbat(int index, unsigned long virt, phys_addr_t phys,
	57	unsigned int size, int flags);
	58
	59	#else /* !HAVE_BATS */
	60	#define v_mapped_by_bats(x) (0UL)
	61	#define p_mapped_by_bats(x) (0UL)
	62	#endif /* HAVE_BATS */
	63
	64	#ifdef HAVE_TLBCAM
	65	extern unsigned int tlbcam_index;
	66	extern phys_addr_t v_mapped_by_tlbcam(unsigned long va);
	67	extern unsigned long p_mapped_by_tlbcam(phys_addr_t pa);
	68	#else /* !HAVE_TLBCAM */
	69	#define v_mapped_by_tlbcam(x) (0UL)
	70	#define p_mapped_by_tlbcam(x) (0UL)
	71	#endif /* HAVE_TLBCAM */
	72
	73	#define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT)
	74
	75	pgd_t pgd_alloc(struct mm_struct mm)
	76	{
	77	pgd_t *ret;
	78
	79	/* pgdir take page or two with 4K pages and a page fraction otherwise */
	80	#ifndef CONFIG_PPC_4K_PAGES
	81	ret = (pgd_t *)kzalloc(1 << PGDIR_ORDER, GFP_KERNEL);
	82	#else
	83	ret = (pgd_t *)__get_free_pages(GFP_KERNEL\|__GFP_ZERO,
	84	PGDIR_ORDER - PAGE_SHIFT);
	85	#endif
	86	return ret;
	87	}
	88
	89	void pgd_free(struct mm_struct mm, pgd_t pgd)
	90	{
	91	#ifndef CONFIG_PPC_4K_PAGES
	92	kfree((void *)pgd);
	93	#else
	94	free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT);
	95	#endif
	96	}
	97
	98	__init_refok pte_t pte_alloc_one_kernel(struct mm_struct mm, unsigned long address)
	99	{
	100	pte_t *pte;
	101	extern int mem_init_done;
	102	extern void *early_get_page(void);
	103
	104	if (mem_init_done) {
	105	pte = (pte_t *)__get_free_page(GFP_KERNEL\|__GFP_REPEAT\|__GFP_ZERO);
	106	} else {
	107	pte = (pte_t *)early_get_page();
	108	if (pte)
	109	clear_page(pte);
	110	}
	111	return pte;
	112	}
	113
	114	pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
	115	{
	116	struct page *ptepage;
	117
	118	gfp_t flags = GFP_KERNEL \| __GFP_REPEAT \| __GFP_ZERO;
	119
	120	ptepage = alloc_pages(flags, 0);
	121	if (!ptepage)
	122	return NULL;
	123	pgtable_page_ctor(ptepage);
	124	return ptepage;
	125	}
	126
	127	void __iomem *
	128	ioremap(phys_addr_t addr, unsigned long size)
	129	{
	130	return __ioremap_caller(addr, size, _PAGE_NO_CACHE \| _PAGE_GUARDED,
	131	__builtin_return_address(0));
	132	}
	133	EXPORT_SYMBOL(ioremap);
	134
	135	void __iomem *
	136	ioremap_flags(phys_addr_t addr, unsigned long size, unsigned long flags)
	137	{
	138	/* writeable implies dirty for kernel addresses */
	139	if (flags & _PAGE_RW)
	140	flags \|= _PAGE_DIRTY \| _PAGE_HWWRITE;
	141
	142	/* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
	143	flags &= ~(_PAGE_USER \| _PAGE_EXEC);
	144
	145	#ifdef _PAGE_BAP_SR
	146	/* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format
	147	* which means that we just cleared supervisor access... oops ;-) This
	148	* restores it
	149	*/
	150	flags \|= _PAGE_BAP_SR;
	151	#endif
	152
	153	return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
	154	}
	155	EXPORT_SYMBOL(ioremap_flags);
	156
	157	void __iomem *
	158	__ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
	159	{
	160	return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
	161	}
	162
	163	void __iomem *
	164	__ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
	165	void *caller)
	166	{
	167	unsigned long v, i;
	168	phys_addr_t p;
	169	int err;
	170
	171	/* Make sure we have the base flags */
	172	if ((flags & _PAGE_PRESENT) == 0)
	173	flags \|= PAGE_KERNEL;
	174
	175	/* Non-cacheable page cannot be coherent */
	176	if (flags & _PAGE_NO_CACHE)
	177	flags &= ~_PAGE_COHERENT;
	178
	179	/*
	180	* Choose an address to map it to.
	181	* Once the vmalloc system is running, we use it.
	182	* Before then, we use space going down from ioremap_base
	183	* (ioremap_bot records where we're up to).
	184	*/
	185	p = addr & PAGE_MASK;
	186	size = PAGE_ALIGN(addr + size) - p;
	187
	188	/*
	189	* If the address lies within the first 16 MB, assume it's in ISA
	190	* memory space
	191	*/
	192	if (p < 1610241024)
	193	p += _ISA_MEM_BASE;
	194
	195	#ifndef CONFIG_CRASH_DUMP
	196	/*
	197	* Don't allow anybody to remap normal RAM that we're using.
	198	* mem_init() sets high_memory so only do the check after that.
	199	*/
	200	if (mem_init_done && (p < virt_to_phys(high_memory)) &&
	201	!(__allow_ioremap_reserved && lmb_is_region_reserved(p, size))) {
	202	printk("__ioremap(): phys addr 0x%llx is RAM lr %p\n",
	203	(unsigned long long)p, __builtin_return_address(0));
	204	return NULL;
	205	}
	206	#endif
	207
	208	if (size == 0)
	209	return NULL;
	210
	211	/*
	212	* Is it already mapped? Perhaps overlapped by a previous
	213	* BAT mapping. If the whole area is mapped then we're done,
	214	* otherwise remap it since we want to keep the virt addrs for
	215	* each request contiguous.
	216	*
	217	* We make the assumption here that if the bottom and top
	218	* of the range we want are mapped then it's mapped to the
	219	* same virt address (and this is contiguous).
	220	* -- Cort
	221	*/
	222	if ((v = p_mapped_by_bats(p)) /&& p_mapped_by_bats(p+size-1)/ )
	223	goto out;
	224
	225	if ((v = p_mapped_by_tlbcam(p)))
	226	goto out;
	227
	228	if (mem_init_done) {
	229	struct vm_struct *area;
	230	area = get_vm_area_caller(size, VM_IOREMAP, caller);
	231	if (area == 0)
	232	return NULL;
	233	v = (unsigned long) area->addr;
	234	} else {
	235	v = (ioremap_bot -= size);
	236	}
	237
	238	/*
	239	* Should check if it is a candidate for a BAT mapping
	240	*/
	241
	242	err = 0;
	243	for (i = 0; i < size && err == 0; i += PAGE_SIZE)
	244	err = map_page(v+i, p+i, flags);
	245	if (err) {
	246	if (mem_init_done)
	247	vunmap((void *)v);
	248	return NULL;
	249	}
	250
	251	out:
	252	return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
	253	}
	254	EXPORT_SYMBOL(__ioremap);
	255
	256	void iounmap(volatile void __iomem *addr)
	257	{
	258	/*
	259	* If mapped by BATs then there is nothing to do.
	260	* Calling vfree() generates a benign warning.
	261	*/
	262	if (v_mapped_by_bats((unsigned long)addr)) return;
	263
	264	if (addr > high_memory && (unsigned long) addr < ioremap_bot)
	265	vunmap((void *) (PAGE_MASK & (unsigned long)addr));
	266	}
	267	EXPORT_SYMBOL(iounmap);
	268
	269	int map_page(unsigned long va, phys_addr_t pa, int flags)
	270	{
	271	pmd_t *pd;
	272	pte_t *pg;
	273	int err = -ENOMEM;
	274
	275	/* Use upper 10 bits of VA to index the first level map */
	276	pd = pmd_offset(pud_offset(pgd_offset_k(va), va), va);
	277	/* Use middle 10 bits of VA to index the second-level map */
	278	pg = pte_alloc_kernel(pd, va);
	279	if (pg != 0) {
	280	err = 0;
	281	/* The PTE should never be already set nor present in the
	282	* hash table
	283	*/
	284	BUG_ON((pte_val(*pg) & (_PAGE_PRESENT \| _PAGE_HASHPTE)) &&
	285	flags);
	286	set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
	287	__pgprot(flags)));
	288	}
	289	return err;
	290	}
	291
	292	/*
	293	* Map in a chunk of physical memory starting at start.
	294	*/
	295	void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
	296	{
	297	unsigned long v, s, f;
	298	phys_addr_t p;
	299	int ktext;
	300
	301	s = offset;
	302	v = PAGE_OFFSET + s;
	303	p = memstart_addr + s;
	304	for (; s < top; s += PAGE_SIZE) {
	305	ktext = ((char ) v >= _stext && (char ) v < etext);
	306	f = ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL;
	307	map_page(v, p, f);
	308	#ifdef CONFIG_PPC_STD_MMU_32
	309	if (ktext)
	310	hash_preload(&init_mm, v, 0, 0x300);
	311	#endif
	312	v += PAGE_SIZE;
	313	p += PAGE_SIZE;
	314	}
	315	}
	316
	317	void __init mapin_ram(void)
	318	{
	319	unsigned long s, top;
	320
	321	#ifndef CONFIG_WII
	322	top = total_lowmem;
	323	s = mmu_mapin_ram(top);
	324	__mapin_ram_chunk(s, top);
	325	#else
	326	if (!wii_hole_size) {
	327	s = mmu_mapin_ram(total_lowmem);
	328	__mapin_ram_chunk(s, total_lowmem);
	329	} else {
	330	top = wii_hole_start;
	331	s = mmu_mapin_ram(top);
	332	__mapin_ram_chunk(s, top);
	333
	334	top = lmb_end_of_DRAM();
	335	s = wii_mmu_mapin_mem2(top);
	336	__mapin_ram_chunk(s, top);
	337	}
	338	#endif
	339	}
	340
	341	/* Scan the real Linux page tables and return a PTE pointer for
	342	* a virtual address in a context.
	343	* Returns true (1) if PTE was found, zero otherwise. The pointer to
	344	* the PTE pointer is unmodified if PTE is not found.
	345	*/
	346	int
	347	get_pteptr(struct mm_struct mm, unsigned long addr, pte_t ptep, pmd_t *pmdp)
	348	{
	349	pgd_t *pgd;
	350	pud_t *pud;
	351	pmd_t *pmd;
	352	pte_t *pte;
	353	int retval = 0;
	354
	355	pgd = pgd_offset(mm, addr & PAGE_MASK);
	356	if (pgd) {
	357	pud = pud_offset(pgd, addr & PAGE_MASK);
	358	if (pud && pud_present(*pud)) {
	359	pmd = pmd_offset(pud, addr & PAGE_MASK);
	360	if (pmd_present(*pmd)) {
	361	pte = pte_offset_map(pmd, addr & PAGE_MASK);
	362	if (pte) {
	363	retval = 1;
	364	*ptep = pte;
	365	if (pmdp)
	366	*pmdp = pmd;
	367	/* XXX caller needs to do pte_unmap, yuck */
	368	}
	369	}
	370	}
	371	}
	372	return(retval);
	373	}
	374
	375	#ifdef CONFIG_DEBUG_PAGEALLOC
	376
	377	static int __change_page_attr(struct page *page, pgprot_t prot)
	378	{
	379	pte_t *kpte;
	380	pmd_t *kpmd;
	381	unsigned long address;
	382
	383	BUG_ON(PageHighMem(page));
	384	address = (unsigned long)page_address(page);
	385
	386	if (v_mapped_by_bats(address) \|\| v_mapped_by_tlbcam(address))
	387	return 0;
	388	if (!get_pteptr(&init_mm, address, &kpte, &kpmd))
	389	return -EINVAL;
	390	__set_pte_at(&init_mm, address, kpte, mk_pte(page, prot), 0);
	391	wmb();
	392	flush_tlb_page(NULL, address);
	393	pte_unmap(kpte);
	394
	395	return 0;
	396	}
	397
	398	/*
	399	* Change the page attributes of an page in the linear mapping.
	400	*
	401	* THIS CONFLICTS WITH BAT MAPPINGS, DEBUG USE ONLY
	402	*/
	403	static int change_page_attr(struct page *page, int numpages, pgprot_t prot)
	404	{
	405	int i, err = 0;
	406	unsigned long flags;
	407
	408	local_irq_save(flags);
	409	for (i = 0; i < numpages; i++, page++) {
	410	err = __change_page_attr(page, prot);
	411	if (err)
	412	break;
	413	}
	414	local_irq_restore(flags);
	415	return err;
	416	}
	417
	418
	419	void kernel_map_pages(struct page *page, int numpages, int enable)
	420	{
	421	if (PageHighMem(page))
	422	return;
	423
	424	change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
	425	}
	426	#endif /* CONFIG_DEBUG_PAGEALLOC */
	427
	428	static int fixmaps;
	429
	430	void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
	431	{
	432	unsigned long address = __fix_to_virt(idx);
	433
	434	if (idx >= __end_of_fixed_addresses) {
	435	BUG();
	436	return;
	437	}
	438
	439	map_page(address, phys, pgprot_val(flags));
	440	fixmaps++;
	441	}
	442
	443	void __this_fixmap_does_not_exist(void)
	444	{
	445	WARN_ON(1);
	446	}