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>

diff --git a/arch/x86/mm/fault_32.c b/arch/x86/mm/fault_32.c
index f7972ae..f4f8c32 100644 (file)
--- a/arch/x86/mm/fault_32.c
+++ b/arch/x86/mm/fault_32.c
@@ -613,7 +613,8 @@ no_context:
 
 #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 5080646..206e3f6 100644 (file)
--- 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 be46564..523fd5b 100644 (file)
--- 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 14ab327..59cd066 100644 (file)
--- 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 e618473..45aa771 100644 (file)
--- 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 eb8cccf..9381bd3 100644 (file)
--- 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 29fdeb8..139da50 100644 (file)
--- 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)