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x86: clean up arch/x86/mm/pageattr_32.c
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clean up arch/x86/mm/pageattr_32.c.

no code changed:

   text    data     bss     dec     hex filename
   1255      40       0    1295     50f pageattr_32.o.before
   1255      40       0    1295     50f pageattr_32.o.after

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Ingo Molnar committed Jan 30, 2008
1 parent 6371b49 commit 9f4c815
Showing 1 changed file with 83 additions and 68 deletions.
151 changes: 83 additions & 68 deletions arch/x86/mm/pageattr_32.c
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Original file line number Diff line number Diff line change
@@ -1,28 +1,29 @@
/*
* Copyright 2002 Andi Kleen, SuSE Labs.
/*
* Copyright 2002 Andi Kleen, SuSE Labs.
* Thanks to Ben LaHaise for precious feedback.
*/
*/

#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/highmem.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <asm/uaccess.h>
#include <linux/mm.h>

#include <asm/processor.h>
#include <asm/tlbflush.h>
#include <asm/pgalloc.h>
#include <asm/sections.h>
#include <asm/uaccess.h>
#include <asm/pgalloc.h>

static DEFINE_SPINLOCK(cpa_lock);
static struct list_head df_list = LIST_HEAD_INIT(df_list);


pte_t *lookup_address(unsigned long address)
{
pte_t *lookup_address(unsigned long address)
{
pgd_t *pgd = pgd_offset_k(address);
pud_t *pud;
pmd_t *pmd;

if (pgd_none(*pgd))
return NULL;
pud = pud_offset(pgd, address);
Expand All @@ -33,21 +34,22 @@ pte_t *lookup_address(unsigned long address)
return NULL;
if (pmd_large(*pmd))
return (pte_t *)pmd;
return pte_offset_kernel(pmd, address);
}

static struct page *split_large_page(unsigned long address, pgprot_t prot,
pgprot_t ref_prot)
{
int i;
return pte_offset_kernel(pmd, address);
}

static struct page *
split_large_page(unsigned long address, pgprot_t prot, pgprot_t ref_prot)
{
unsigned long addr;
struct page *base;
pte_t *pbase;
int i;

spin_unlock_irq(&cpa_lock);
base = alloc_pages(GFP_KERNEL, 0);
spin_lock_irq(&cpa_lock);
if (!base)
if (!base)
return NULL;

/*
Expand All @@ -58,22 +60,24 @@ static struct page *split_large_page(unsigned long address, pgprot_t prot,
page_private(base) = 0;

address = __pa(address);
addr = address & LARGE_PAGE_MASK;
addr = address & LARGE_PAGE_MASK;
pbase = (pte_t *)page_address(base);
paravirt_alloc_pt(&init_mm, page_to_pfn(base));

for (i = 0; i < PTRS_PER_PTE; i++, addr += PAGE_SIZE) {
set_pte(&pbase[i], pfn_pte(addr >> PAGE_SHIFT,
addr == address ? prot : ref_prot));
set_pte(&pbase[i], pfn_pte(addr >> PAGE_SHIFT,
addr == address ? prot : ref_prot));
}
return base;
}
}

static void cache_flush_page(struct page *p)
{
void *adr = page_address(p);
{
void *addr = page_address(p);
int i;

for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size)
clflush(adr+i);
clflush(addr + i);
}

static void flush_kernel_map(void *arg)
Expand All @@ -83,23 +87,27 @@ static void flush_kernel_map(void *arg)

/* High level code is not ready for clflush yet */
if (0 && cpu_has_clflush) {
list_for_each_entry (p, lh, lru)
list_for_each_entry(p, lh, lru)
cache_flush_page(p);
} else if (boot_cpu_data.x86_model >= 4)
wbinvd();
} else {
if (boot_cpu_data.x86_model >= 4)
wbinvd();
}

/* Flush all to work around Errata in early athlons regarding
* large page flushing.
/*
* Flush all to work around Errata in early athlons regarding
* large page flushing.
*/
__flush_tlb_all();
__flush_tlb_all();
}

static void set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
{
struct page *page;
static void set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
{
unsigned long flags;
struct page *page;

set_pte_atomic(kpte, pte); /* change init_mm */
/* change init_mm */
set_pte_atomic(kpte, pte);
if (SHARED_KERNEL_PMD)
return;

Expand All @@ -108,6 +116,7 @@ static void set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;

pgd = (pgd_t *)page_address(page) + pgd_index(address);
pud = pud_offset(pgd, address);
pmd = pmd_offset(pud, address);
Expand All @@ -116,9 +125,9 @@ static void set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
spin_unlock_irqrestore(&pgd_lock, flags);
}

/*
* No more special protections in this 2/4MB area - revert to a
* large page again.
/*
* No more special protections in this 2/4MB area - revert to a large
* page again.
*/
static inline void revert_page(struct page *kpte_page, unsigned long address)
{
Expand All @@ -142,46 +151,49 @@ static inline void save_page(struct page *kpte_page)
list_add(&kpte_page->lru, &df_list);
}

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

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

kpte = lookup_address(address);
if (!kpte)
return -EINVAL;

kpte_page = virt_to_page(kpte);
BUG_ON(PageLRU(kpte_page));
BUG_ON(PageCompound(kpte_page));

if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL)) {
if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL)) {
if (!pte_huge(*kpte)) {
set_pte_atomic(kpte, mk_pte(page, prot));
set_pte_atomic(kpte, mk_pte(page, prot));
} else {
pgprot_t ref_prot;
struct page *split;
pgprot_t ref_prot;

ref_prot =
((address & LARGE_PAGE_MASK) < (unsigned long)&_etext)
? PAGE_KERNEL_EXEC : PAGE_KERNEL;
split = split_large_page(address, prot, ref_prot);
if (!split)
return -ENOMEM;
set_pmd_pte(kpte,address,mk_pte(split, ref_prot));

set_pmd_pte(kpte, address, mk_pte(split, ref_prot));
kpte_page = split;
}
page_private(kpte_page)++;
} else if (!pte_huge(*kpte)) {
set_pte_atomic(kpte, mk_pte(page, PAGE_KERNEL));
BUG_ON(page_private(kpte_page) == 0);
page_private(kpte_page)--;
} else
BUG();
} else {
if (!pte_huge(*kpte)) {
set_pte_atomic(kpte, mk_pte(page, PAGE_KERNEL));
BUG_ON(page_private(kpte_page) == 0);
page_private(kpte_page)--;
} else
BUG();
}

/*
* If the pte was reserved, it means it was created at boot
Expand All @@ -197,7 +209,7 @@ __change_page_attr(struct page *page, pgprot_t prot)
}
}
return 0;
}
}

static inline void flush_map(struct list_head *l)
{
Expand All @@ -211,32 +223,33 @@ static inline void flush_map(struct list_head *l)
* than write-back somewhere - some CPUs do not like it when mappings with
* different caching policies exist. This changes the page attributes of the
* in kernel linear mapping too.
*
*
* The caller needs to ensure that there are no conflicting mappings elsewhere.
* This function only deals with the kernel linear map.
*
*
* Caller must call global_flush_tlb() after this.
*/
int change_page_attr(struct page *page, int numpages, pgprot_t prot)
{
int err = 0;
int i;
unsigned long flags;
int err = 0, i;

spin_lock_irqsave(&cpa_lock, flags);
for (i = 0; i < numpages; i++, page++) {
for (i = 0; i < numpages; i++, page++) {
err = __change_page_attr(page, prot);
if (err)
break;
}
if (err)
break;
}
spin_unlock_irqrestore(&cpa_lock, flags);

return err;
}
EXPORT_SYMBOL(change_page_attr);

void global_flush_tlb(void)
{
struct list_head l;
struct page *pg, *next;
struct list_head l;

BUG_ON(irqs_disabled());

Expand All @@ -253,26 +266,28 @@ void global_flush_tlb(void)
__free_page(pg);
}
}
EXPORT_SYMBOL(global_flush_tlb);

#ifdef CONFIG_DEBUG_PAGEALLOC
void kernel_map_pages(struct page *page, int numpages, int enable)
{
if (PageHighMem(page))
return;
if (!enable)
if (!enable) {
debug_check_no_locks_freed(page_address(page),
numpages * PAGE_SIZE);
}

/* the return value is ignored - the calls cannot fail,
/*
* the return value is ignored - the calls cannot fail,
* large pages are disabled at boot time.
*/
change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
/* we should perform an IPI and flush all tlbs,

/*
* we should perform an IPI and flush all tlbs,
* but that can deadlock->flush only current cpu.
*/
__flush_tlb_all();
}
#endif

EXPORT_SYMBOL(change_page_attr);
EXPORT_SYMBOL(global_flush_tlb);

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