[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 <asm/pgtable.h>
#include <asm/pgalloc.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 CONFIG_SMP
extern void hash_page_sync(void);
#endif

#ifdef HAVE_BATS
extern unsigned long v_mapped_by_bats(unsigned long va);
extern unsigned long p_mapped_by_bats(unsigned long pa);
void setbat(int index, unsigned long virt, unsigned long 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 unsigned long v_mapped_by_tlbcam(unsigned long va);
extern unsigned long p_mapped_by_tlbcam(unsigned long pa);
#else /* !HAVE_TLBCAM */
#define v_mapped_by_tlbcam(x)	(0UL)
#define p_mapped_by_tlbcam(x)	(0UL)
#endif /* HAVE_TLBCAM */

#ifdef CONFIG_PTE_64BIT
/* 44x uses an 8kB pgdir because it has 8-byte Linux PTEs. */
#define PGDIR_ORDER	1
#else
#define PGDIR_ORDER	0
#endif

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

	ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, PGDIR_ORDER);
	return ret;
}

void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
	free_pages((unsigned long)pgd, PGDIR_ORDER);
}

__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;
}

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

#ifdef CONFIG_HIGHPTE
	gfp_t flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_REPEAT;
#else
	gfp_t flags = GFP_KERNEL | __GFP_REPEAT;
#endif

	ptepage = alloc_pages(flags, 0);
	if (ptepage)
		clear_highpage(ptepage);
	return ptepage;
}

void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
{
#ifdef CONFIG_SMP
	hash_page_sync();
#endif
	free_page((unsigned long)pte);
}

void pte_free(struct mm_struct *mm, struct page *ptepage)
{
#ifdef CONFIG_SMP
	hash_page_sync();
#endif
	__free_page(ptepage);
}

void __iomem *
ioremap(phys_addr_t addr, unsigned long size)
{
	return __ioremap(addr, size, _PAGE_NO_CACHE);
}
EXPORT_SYMBOL(ioremap);

void __iomem *
ioremap_flags(phys_addr_t addr, unsigned long size, unsigned long flags)
{
	return __ioremap(addr, size, flags);
}
EXPORT_SYMBOL(ioremap_flags);

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

	/*
	 * 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;

	/*
	 * 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))) {
		printk("__ioremap(): phys addr 0x%llx is RAM lr %p\n",
		       (unsigned long long)p, __builtin_return_address(0));
		return NULL;
	}

	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(size, VM_IOREMAP);
		if (area == 0)
			return NULL;
		v = (unsigned long) area->addr;
	} else {
		v = (ioremap_bot -= size);
	}

	if ((flags & _PAGE_PRESENT) == 0)
		flags |= _PAGE_KERNEL;
	if (flags & _PAGE_NO_CACHE)
		flags |= _PAGE_GUARDED;

	/*
	 * 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));
		set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
						     __pgprot(flags)));
	}
	return err;
}

/*
 * Map in all of physical memory starting at KERNELBASE.
 */
void __init mapin_ram(void)
{
	unsigned long v, p, s, f;
	int ktext;

	s = mmu_mapin_ram();
	v = KERNELBASE + s;
	p = PPC_MEMSTART + s;
	for (; s < total_lowmem; s += PAGE_SIZE) {
		ktext = ((char *) v >= _stext && (char *) v < etext);
		f = ktext ?_PAGE_RAM_TEXT : _PAGE_RAM;
		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;
	}
}

/* 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));
	wmb();
	flush_HPTE(0, address, pmd_val(*kpmd));
	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 */
Commit	Line	Data
14cf11af PM	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
14cf11af PM	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
14cf11af PM	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
	30	#include <asm/pgtable.h>
	31	#include <asm/pgalloc.h>
	32	#include <asm/io.h>
	33
	34	#include "mmu_decl.h"
	35
	36	unsigned long ioremap_base;
	37	unsigned long ioremap_bot;
920573bd	38	EXPORT_SYMBOL(ioremap_bot); /* aka VMALLOC_END */
14cf11af PM	39
	40	#if defined(CONFIG_6xx) \|\| defined(CONFIG_POWER3)
	41	#define HAVE_BATS 1
	42	#endif
	43
	44	#if defined(CONFIG_FSL_BOOKE)
	45	#define HAVE_TLBCAM 1
	46	#endif
	47
	48	extern char etext[], _stext[];
	49
	50	#ifdef CONFIG_SMP
	51	extern void hash_page_sync(void);
	52	#endif
	53
	54	#ifdef HAVE_BATS
	55	extern unsigned long v_mapped_by_bats(unsigned long va);
	56	extern unsigned long p_mapped_by_bats(unsigned long pa);
	57	void setbat(int index, unsigned long virt, unsigned long phys,
	58	unsigned int size, int flags);
	59
	60	#else /* !HAVE_BATS */
	61	#define v_mapped_by_bats(x) (0UL)
	62	#define p_mapped_by_bats(x) (0UL)
	63	#endif /* HAVE_BATS */
	64
	65	#ifdef HAVE_TLBCAM
	66	extern unsigned int tlbcam_index;
	67	extern unsigned long v_mapped_by_tlbcam(unsigned long va);
	68	extern unsigned long p_mapped_by_tlbcam(unsigned long pa);
	69	#else /* !HAVE_TLBCAM */
	70	#define v_mapped_by_tlbcam(x) (0UL)
	71	#define p_mapped_by_tlbcam(x) (0UL)
	72	#endif /* HAVE_TLBCAM */
	73
	74	#ifdef CONFIG_PTE_64BIT
	75	/* 44x uses an 8kB pgdir because it has 8-byte Linux PTEs. */
	76	#define PGDIR_ORDER 1
	77	#else
	78	#define PGDIR_ORDER 0
	79	#endif
	80
	81	pgd_t pgd_alloc(struct mm_struct mm)
	82	{
	83	pgd_t *ret;
	84
	85	ret = (pgd_t *)__get_free_pages(GFP_KERNEL\|__GFP_ZERO, PGDIR_ORDER);
	86	return ret;
	87	}
	88
5e541973	89	void pgd_free(struct mm_struct mm, pgd_t pgd)
14cf11af PM	90	{
	91	free_pages((unsigned long)pgd, PGDIR_ORDER);
	92	}
	93
f1aed924	94	__init_refok pte_t pte_alloc_one_kernel(struct mm_struct mm, unsigned long address)
14cf11af PM	95	{
	96	pte_t *pte;
	97	extern int mem_init_done;
	98	extern void *early_get_page(void);
	99
	100	if (mem_init_done) {
	101	pte = (pte_t *)__get_free_page(GFP_KERNEL\|__GFP_REPEAT\|__GFP_ZERO);
	102	} else {
	103	pte = (pte_t *)early_get_page();
	104	if (pte)
	105	clear_page(pte);
	106	}
	107	return pte;
	108	}
	109
	110	struct page pte_alloc_one(struct mm_struct mm, unsigned long address)
	111	{
	112	struct page *ptepage;
	113
	114	#ifdef CONFIG_HIGHPTE
3ee1fcac	115	gfp_t flags = GFP_KERNEL \| __GFP_HIGHMEM \| __GFP_REPEAT;
14cf11af	116	#else
3ee1fcac	117	gfp_t flags = GFP_KERNEL \| __GFP_REPEAT;
14cf11af PM	118	#endif
	119
	120	ptepage = alloc_pages(flags, 0);
	121	if (ptepage)
	122	clear_highpage(ptepage);
	123	return ptepage;
	124	}
	125
5e541973	126	void pte_free_kernel(struct mm_struct mm, pte_t pte)
14cf11af PM	127	{
	128	#ifdef CONFIG_SMP
	129	hash_page_sync();
	130	#endif
	131	free_page((unsigned long)pte);
	132	}
	133
5e541973	134	void pte_free(struct mm_struct mm, struct page ptepage)
14cf11af PM	135	{
	136	#ifdef CONFIG_SMP
	137	hash_page_sync();
	138	#endif
	139	__free_page(ptepage);
	140	}
	141
14cf11af PM	142	void __iomem *
	143	ioremap(phys_addr_t addr, unsigned long size)
	144	{
	145	return __ioremap(addr, size, _PAGE_NO_CACHE);
	146	}
920573bd	147	EXPORT_SYMBOL(ioremap);
14cf11af	148
68a64357 BH	149	void __iomem *
	150	ioremap_flags(phys_addr_t addr, unsigned long size, unsigned long flags)
	151	{
	152	return __ioremap(addr, size, flags);
	153	}
	154	EXPORT_SYMBOL(ioremap_flags);
	155
14cf11af PM	156	void __iomem *
	157	__ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
	158	{
	159	unsigned long v, i;
	160	phys_addr_t p;
	161	int err;
	162
	163	/*
	164	* Choose an address to map it to.
	165	* Once the vmalloc system is running, we use it.
	166	* Before then, we use space going down from ioremap_base
	167	* (ioremap_bot records where we're up to).
	168	*/
	169	p = addr & PAGE_MASK;
	170	size = PAGE_ALIGN(addr + size) - p;
	171
	172	/*
	173	* If the address lies within the first 16 MB, assume it's in ISA
	174	* memory space
	175	*/
	176	if (p < 1610241024)
	177	p += _ISA_MEM_BASE;
	178
	179	/*
	180	* Don't allow anybody to remap normal RAM that we're using.
	181	* mem_init() sets high_memory so only do the check after that.
	182	*/
7c8c6b97	183	if (mem_init_done && (p < virt_to_phys(high_memory))) {
37f01d64 DG	184	printk("__ioremap(): phys addr 0x%llx is RAM lr %p\n",
37f01d64 DG	185	(unsigned long long)p, __builtin_return_address(0));
14cf11af PM	186	return NULL;
	187	}
	188
	189	if (size == 0)
	190	return NULL;
	191
	192	/*
	193	* Is it already mapped? Perhaps overlapped by a previous
	194	* BAT mapping. If the whole area is mapped then we're done,
	195	* otherwise remap it since we want to keep the virt addrs for
	196	* each request contiguous.
	197	*
	198	* We make the assumption here that if the bottom and top
	199	* of the range we want are mapped then it's mapped to the
	200	* same virt address (and this is contiguous).
	201	* -- Cort
	202	*/
	203	if ((v = p_mapped_by_bats(p)) /&& p_mapped_by_bats(p+size-1)/ )
	204	goto out;
	205
	206	if ((v = p_mapped_by_tlbcam(p)))
	207	goto out;
	208
	209	if (mem_init_done) {
	210	struct vm_struct *area;
	211	area = get_vm_area(size, VM_IOREMAP);
	212	if (area == 0)
	213	return NULL;
	214	v = (unsigned long) area->addr;
	215	} else {
	216	v = (ioremap_bot -= size);
	217	}
	218
	219	if ((flags & _PAGE_PRESENT) == 0)
	220	flags \|= _PAGE_KERNEL;
	221	if (flags & _PAGE_NO_CACHE)
	222	flags \|= _PAGE_GUARDED;
	223
	224	/*
	225	* Should check if it is a candidate for a BAT mapping
	226	*/
	227
	228	err = 0;
	229	for (i = 0; i < size && err == 0; i += PAGE_SIZE)
	230	err = map_page(v+i, p+i, flags);
	231	if (err) {
	232	if (mem_init_done)
	233	vunmap((void *)v);
	234	return NULL;
	235	}
	236
	237	out:
	238	return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
	239	}
920573bd	240	EXPORT_SYMBOL(__ioremap);
14cf11af PM	241
	242	void iounmap(volatile void __iomem *addr)
	243	{
	244	/*
	245	* If mapped by BATs then there is nothing to do.
	246	* Calling vfree() generates a benign warning.
	247	*/
	248	if (v_mapped_by_bats((unsigned long)addr)) return;
	249
	250	if (addr > high_memory && (unsigned long) addr < ioremap_bot)
	251	vunmap((void *) (PAGE_MASK & (unsigned long)addr));
	252	}
920573bd	253	EXPORT_SYMBOL(iounmap);
14cf11af	254
68a64357	255	int map_page(unsigned long va, phys_addr_t pa, int flags)
14cf11af PM	256	{
	257	pmd_t *pd;
	258	pte_t *pg;
	259	int err = -ENOMEM;
	260
14cf11af	261	/* Use upper 10 bits of VA to index the first level map */
d1953c88	262	pd = pmd_offset(pud_offset(pgd_offset_k(va), va), va);
14cf11af	263	/* Use middle 10 bits of VA to index the second-level map */
e2f2e58e	264	pg = pte_alloc_kernel(pd, va);
14cf11af PM	265	if (pg != 0) {
14cf11af PM	266	err = 0;
3be4e699 BH	267	/* The PTE should never be already set nor present in the
	268	* hash table
	269	*/
	270	BUG_ON(pte_val(*pg) & (_PAGE_PRESENT \| _PAGE_HASHPTE));
	271	set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
	272	__pgprot(flags)));
14cf11af	273	}
14cf11af PM	274	return err;
	275	}
	276
	277	/*
	278	* Map in all of physical memory starting at KERNELBASE.
	279	*/
	280	void __init mapin_ram(void)
	281	{
	282	unsigned long v, p, s, f;
ee4f2ea4	283	int ktext;
14cf11af PM	284
	285	s = mmu_mapin_ram();
	286	v = KERNELBASE + s;
	287	p = PPC_MEMSTART + s;
	288	for (; s < total_lowmem; s += PAGE_SIZE) {
ee4f2ea4 BH	289	ktext = ((char ) v >= _stext && (char ) v < etext);
ee4f2ea4 BH	290	f = ktext ?_PAGE_RAM_TEXT : _PAGE_RAM;
14cf11af	291	map_page(v, p, f);
ee4f2ea4 BH	292	#ifdef CONFIG_PPC_STD_MMU_32
	293	if (ktext)
	294	hash_preload(&init_mm, v, 0, 0x300);
	295	#endif
14cf11af PM	296	v += PAGE_SIZE;
	297	p += PAGE_SIZE;
	298	}
	299	}
	300
14cf11af PM	301	/* Scan the real Linux page tables and return a PTE pointer for
	302	* a virtual address in a context.
	303	* Returns true (1) if PTE was found, zero otherwise. The pointer to
	304	* the PTE pointer is unmodified if PTE is not found.
	305	*/
	306	int
bab70a4a	307	get_pteptr(struct mm_struct mm, unsigned long addr, pte_t ptep, pmd_t *pmdp)
14cf11af PM	308	{
14cf11af PM	309	pgd_t *pgd;
d1953c88	310	pud_t *pud;
14cf11af PM	311	pmd_t *pmd;
	312	pte_t *pte;
	313	int retval = 0;
	314
	315	pgd = pgd_offset(mm, addr & PAGE_MASK);
	316	if (pgd) {
d1953c88 DG	317	pud = pud_offset(pgd, addr & PAGE_MASK);
	318	if (pud && pud_present(*pud)) {
	319	pmd = pmd_offset(pud, addr & PAGE_MASK);
	320	if (pmd_present(*pmd)) {
	321	pte = pte_offset_map(pmd, addr & PAGE_MASK);
	322	if (pte) {
	323	retval = 1;
	324	*ptep = pte;
	325	if (pmdp)
	326	*pmdp = pmd;
	327	/* XXX caller needs to do pte_unmap, yuck */
	328	}
	329	}
	330	}
14cf11af PM	331	}
	332	return(retval);
	333	}
	334
88df6e90 BH	335	#ifdef CONFIG_DEBUG_PAGEALLOC
	336
	337	static int __change_page_attr(struct page *page, pgprot_t prot)
	338	{
	339	pte_t *kpte;
	340	pmd_t *kpmd;
	341	unsigned long address;
	342
	343	BUG_ON(PageHighMem(page));
	344	address = (unsigned long)page_address(page);
	345
	346	if (v_mapped_by_bats(address) \|\| v_mapped_by_tlbcam(address))
	347	return 0;
	348	if (!get_pteptr(&init_mm, address, &kpte, &kpmd))
	349	return -EINVAL;
	350	set_pte_at(&init_mm, address, kpte, mk_pte(page, prot));
	351	wmb();
	352	flush_HPTE(0, address, pmd_val(*kpmd));
	353	pte_unmap(kpte);
	354
	355	return 0;
	356	}
	357
	358	/*
	359	* Change the page attributes of an page in the linear mapping.
	360	*
	361	* THIS CONFLICTS WITH BAT MAPPINGS, DEBUG USE ONLY
	362	*/
	363	static int change_page_attr(struct page *page, int numpages, pgprot_t prot)
	364	{
	365	int i, err = 0;
	366	unsigned long flags;
	367
	368	local_irq_save(flags);
	369	for (i = 0; i < numpages; i++, page++) {
	370	err = __change_page_attr(page, prot);
	371	if (err)
	372	break;
	373	}
	374	local_irq_restore(flags);
	375	return err;
	376	}
	377
	378
	379	void kernel_map_pages(struct page *page, int numpages, int enable)
	380	{
	381	if (PageHighMem(page))
	382	return;
	383
	384	change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
	385	}
	386	#endif /* CONFIG_DEBUG_PAGEALLOC */