From f0646e43acb18f0e00b00085dc88bc3f403e7930 Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Wed, 30 Jan 2008 13:33:43 +0100
Subject: [PATCH] x86: return the page table level in lookup_address()
based on this patch from Andi Kleen:
| Subject: CPA: Return the page table level in lookup_address()
| From: Andi Kleen <ak@suse.de>
|
| Needed for the next change.
|
| And change all the callers.
and ported it to x86.git.
Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/mm/fault_32.c | 3 ++-
arch/x86/mm/init_32.c | 3 ++-
arch/x86/mm/pageattr_32.c | 7 +++++--
arch/x86/mm/pageattr_64.c | 7 +++++--
arch/x86/xen/mmu.c | 9 ++++++---
include/asm-x86/pgtable_32.h | 2 +-
include/asm-x86/pgtable_64.h | 2 +-
7 files changed, 22 insertions(+), 11 deletions(-)
diff --git a/arch/x86/mm/fault_32.c b/arch/x86/mm/fault_32.c
index f7972ae7da07..f4f8c324715f 100644
--- a/arch/x86/mm/fault_32.c
+++ b/arch/x86/mm/fault_32.c
@@ -613,7 +613,8 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
#ifdef CONFIG_X86_PAE
if (error_code & PF_INSTR) {
- pte_t *pte = lookup_address(address);
+ int level;
+ pte_t *pte = lookup_address(address, &level);
if (pte && pte_present(*pte) && !pte_exec(*pte))
printk(KERN_CRIT "kernel tried to execute "
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 5080646da771..206e3f6800b9 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -535,11 +535,12 @@ int __init set_kernel_exec(unsigned long vaddr, int enable)
{
pte_t *pte;
int ret = 1;
+ int level;
if (!nx_enabled)
goto out;
- pte = lookup_address(vaddr);
+ pte = lookup_address(vaddr, &level);
BUG_ON(!pte);
if (!pte_exec(*pte))
diff --git a/arch/x86/mm/pageattr_32.c b/arch/x86/mm/pageattr_32.c
index be4656403d77..523fd5b37df9 100644
--- a/arch/x86/mm/pageattr_32.c
+++ b/arch/x86/mm/pageattr_32.c
@@ -18,7 +18,7 @@
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, int *level)
{
pgd_t *pgd = pgd_offset_k(address);
pud_t *pud;
@@ -32,8 +32,10 @@ pte_t *lookup_address(unsigned long address)
pmd = pmd_offset(pud, address);
if (pmd_none(*pmd))
return NULL;
+ *level = 2;
if (pmd_large(*pmd))
return (pte_t *)pmd;
+ *level = 3;
return pte_offset_kernel(pmd, address);
}
@@ -156,11 +158,12 @@ static int __change_page_attr(struct page *page, pgprot_t prot)
struct page *kpte_page;
unsigned long address;
pte_t *kpte;
+ int level;
BUG_ON(PageHighMem(page));
address = (unsigned long)page_address(page);
- kpte = lookup_address(address);
+ kpte = lookup_address(address, &level);
if (!kpte)
return -EINVAL;
diff --git a/arch/x86/mm/pageattr_64.c b/arch/x86/mm/pageattr_64.c
index 14ab327cde0c..59cd066f6741 100644
--- a/arch/x86/mm/pageattr_64.c
+++ b/arch/x86/mm/pageattr_64.c
@@ -14,7 +14,7 @@
#include <asm/uaccess.h>
#include <asm/io.h>
-pte_t *lookup_address(unsigned long address)
+pte_t *lookup_address(unsigned long address, int *level)
{
pgd_t *pgd = pgd_offset_k(address);
pud_t *pud;
@@ -29,8 +29,10 @@ pte_t *lookup_address(unsigned long address)
pmd = pmd_offset(pud, address);
if (!pmd_present(*pmd))
return NULL;
+ *level = 3;
if (pmd_large(*pmd))
return (pte_t *)pmd;
+ *level = 4;
pte = pte_offset_kernel(pmd, address);
if (pte && !pte_present(*pte))
@@ -140,8 +142,9 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
struct page *kpte_page;
pgprot_t ref_prot2;
pte_t *kpte;
+ int level;
- kpte = lookup_address(address);
+ kpte = lookup_address(address, &level);
if (!kpte)
return 0;
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index e6184735545f..45aa771e73a9 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -58,7 +58,8 @@
xmaddr_t arbitrary_virt_to_machine(unsigned long address)
{
- pte_t *pte = lookup_address(address);
+ int level;
+ pte_t *pte = lookup_address(address, &level);
unsigned offset = address & PAGE_MASK;
BUG_ON(pte == NULL);
@@ -70,8 +71,9 @@ void make_lowmem_page_readonly(void *vaddr)
{
pte_t *pte, ptev;
unsigned long address = (unsigned long)vaddr;
+ int level;
- pte = lookup_address(address);
+ pte = lookup_address(address, &level);
BUG_ON(pte == NULL);
ptev = pte_wrprotect(*pte);
@@ -84,8 +86,9 @@ void make_lowmem_page_readwrite(void *vaddr)
{
pte_t *pte, ptev;
unsigned long address = (unsigned long)vaddr;
+ int level;
- pte = lookup_address(address);
+ pte = lookup_address(address, &level);
BUG_ON(pte == NULL);
ptev = pte_mkwrite(*pte);
diff --git a/include/asm-x86/pgtable_32.h b/include/asm-x86/pgtable_32.h
index eb8cccfa6a49..9381bd37b9b1 100644
--- a/include/asm-x86/pgtable_32.h
+++ b/include/asm-x86/pgtable_32.h
@@ -182,7 +182,7 @@ static inline void clone_pgd_range(pgd_t *dst, pgd_t *src, int count)
* NOTE: the return type is pte_t but if the pmd is PSE then we return it
* as a pte too.
*/
-extern pte_t *lookup_address(unsigned long address);
+extern pte_t *lookup_address(unsigned long address, int *level);
/*
* Make a given kernel text page executable/non-executable.
diff --git a/include/asm-x86/pgtable_64.h b/include/asm-x86/pgtable_64.h
index 29fdeb8111bb..139da50cd510 100644
--- a/include/asm-x86/pgtable_64.h
+++ b/include/asm-x86/pgtable_64.h
@@ -240,7 +240,7 @@ extern struct list_head pgd_list;
extern int kern_addr_valid(unsigned long addr);
-pte_t *lookup_address(unsigned long addr);
+pte_t *lookup_address(unsigned long addr, int *level);
#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
remap_pfn_range(vma, vaddr, pfn, size, prot)
--
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