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-rw-r--r--arch/x86/mm/pageattr_64.c143
1 files changed, 81 insertions, 62 deletions
diff --git a/arch/x86/mm/pageattr_64.c b/arch/x86/mm/pageattr_64.c
index c40afbaaf93..14ab327cde0 100644
--- a/arch/x86/mm/pageattr_64.c
+++ b/arch/x86/mm/pageattr_64.c
@@ -1,48 +1,54 @@
-/*
- * 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/uaccess.h>
#include <asm/io.h>
pte_t *lookup_address(unsigned long address)
-{
+{
pgd_t *pgd = pgd_offset_k(address);
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
+
if (pgd_none(*pgd))
return NULL;
pud = pud_offset(pgd, address);
if (!pud_present(*pud))
- return NULL;
+ return NULL;
pmd = pmd_offset(pud, address);
if (!pmd_present(*pmd))
- return NULL;
+ return NULL;
if (pmd_large(*pmd))
return (pte_t *)pmd;
+
pte = pte_offset_kernel(pmd, address);
if (pte && !pte_present(*pte))
- pte = NULL;
+ pte = NULL;
+
return pte;
-}
+}
-static struct page *split_large_page(unsigned long address, pgprot_t prot,
- pgprot_t ref_prot)
-{
- int i;
+static struct page *
+split_large_page(unsigned long address, pgprot_t prot, pgprot_t ref_prot)
+{
unsigned long addr;
- struct page *base = alloc_pages(GFP_KERNEL, 0);
+ struct page *base;
pte_t *pbase;
- if (!base)
+ int i;
+
+ base = alloc_pages(GFP_KERNEL, 0);
+ if (!base)
return NULL;
/*
* page_private is used to track the number of entries in
@@ -52,20 +58,21 @@ 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);
for (i = 0; i < PTRS_PER_PTE; i++, addr += PAGE_SIZE) {
- pbase[i] = pfn_pte(addr >> PAGE_SHIFT,
+ pbase[i] = pfn_pte(addr >> PAGE_SHIFT,
addr == address ? prot : ref_prot);
}
return base;
-}
+}
-void clflush_cache_range(void *adr, int size)
+void clflush_cache_range(void *addr, int size)
{
int i;
+
for (i = 0; i < size; i += boot_cpu_data.x86_clflush_size)
- clflush(adr+i);
+ clflush(addr+i);
}
static void flush_kernel_map(void *arg)
@@ -76,17 +83,20 @@ static void flush_kernel_map(void *arg)
/* When clflush is available always use it because it is
much cheaper than WBINVD. */
/* clflush is still broken. Disable for now. */
- if (1 || !cpu_has_clflush)
+ if (1 || !cpu_has_clflush) {
asm volatile("wbinvd" ::: "memory");
- else list_for_each_entry(pg, l, lru) {
- void *adr = page_address(pg);
- clflush_cache_range(adr, PAGE_SIZE);
+ } else {
+ list_for_each_entry(pg, l, lru) {
+ void *addr = page_address(pg);
+
+ clflush_cache_range(addr, PAGE_SIZE);
+ }
}
__flush_tlb_all();
}
static inline void flush_map(struct list_head *l)
-{
+{
on_each_cpu(flush_kernel_map, l, 1, 1);
}
@@ -98,52 +108,56 @@ static inline void save_page(struct page *fpage)
list_add(&fpage->lru, &deferred_pages);
}
-/*
+/*
* No more special protections in this 2/4MB area - revert to a
- * large page again.
+ * large page again.
*/
static void revert_page(unsigned long address, pgprot_t ref_prot)
{
+ unsigned long pfn;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t large_pte;
- unsigned long pfn;
pgd = pgd_offset_k(address);
BUG_ON(pgd_none(*pgd));
- pud = pud_offset(pgd,address);
+ pud = pud_offset(pgd, address);
BUG_ON(pud_none(*pud));
pmd = pmd_offset(pud, address);
BUG_ON(pmd_val(*pmd) & _PAGE_PSE);
pfn = (__pa(address) & LARGE_PAGE_MASK) >> PAGE_SHIFT;
large_pte = pfn_pte(pfn, ref_prot);
large_pte = pte_mkhuge(large_pte);
+
set_pte((pte_t *)pmd, large_pte);
-}
+}
static int
__change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
- pgprot_t ref_prot)
-{
- pte_t *kpte;
+ pgprot_t ref_prot)
+{
struct page *kpte_page;
pgprot_t ref_prot2;
+ pte_t *kpte;
kpte = lookup_address(address);
- if (!kpte) return 0;
+ if (!kpte)
+ return 0;
+
kpte_page = virt_to_page(((unsigned long)kpte) & PAGE_MASK);
BUG_ON(PageLRU(kpte_page));
BUG_ON(PageCompound(kpte_page));
- if (pgprot_val(prot) != pgprot_val(ref_prot)) {
+ if (pgprot_val(prot) != pgprot_val(ref_prot)) {
if (!pte_huge(*kpte)) {
set_pte(kpte, pfn_pte(pfn, prot));
} else {
- /*
+ /*
* split_large_page will take the reference for this
* change_page_attr on the split page.
- */
+ */
struct page *split;
+
ref_prot2 = pte_pgprot(pte_clrhuge(*kpte));
split = split_large_page(address, prot, ref_prot2);
if (!split)
@@ -153,21 +167,23 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
kpte_page = split;
}
page_private(kpte_page)++;
- } else if (!pte_huge(*kpte)) {
- set_pte(kpte, pfn_pte(pfn, ref_prot));
- BUG_ON(page_private(kpte_page) == 0);
- page_private(kpte_page)--;
- } else
- BUG();
+ } else {
+ if (!pte_huge(*kpte)) {
+ set_pte(kpte, pfn_pte(pfn, ref_prot));
+ BUG_ON(page_private(kpte_page) == 0);
+ page_private(kpte_page)--;
+ } else
+ BUG();
+ }
/* on x86-64 the direct mapping set at boot is not using 4k pages */
- BUG_ON(PageReserved(kpte_page));
+ BUG_ON(PageReserved(kpte_page));
save_page(kpte_page);
if (page_private(kpte_page) == 0)
revert_page(address, ref_prot);
return 0;
-}
+}
/*
* Change the page attributes of an page in the linear mapping.
@@ -176,19 +192,19 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
* 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_addr(unsigned long address, int numpages, pgprot_t prot)
{
- int err = 0, kernel_map = 0;
- int i;
+ int err = 0, kernel_map = 0, i;
+
+ if (address >= __START_KERNEL_map &&
+ address < __START_KERNEL_map + KERNEL_TEXT_SIZE) {
- if (address >= __START_KERNEL_map
- && address < __START_KERNEL_map + KERNEL_TEXT_SIZE) {
address = (unsigned long)__va(__pa(address));
kernel_map = 1;
}
@@ -198,7 +214,8 @@ int change_page_attr_addr(unsigned long address, int numpages, pgprot_t prot)
unsigned long pfn = __pa(address) >> PAGE_SHIFT;
if (!kernel_map || pte_present(pfn_pte(0, prot))) {
- err = __change_page_attr(address, pfn, prot, PAGE_KERNEL);
+ err = __change_page_attr(address, pfn, prot,
+ PAGE_KERNEL);
if (err)
break;
}
@@ -207,14 +224,16 @@ int change_page_attr_addr(unsigned long address, int numpages, pgprot_t prot)
if (__pa(address) < KERNEL_TEXT_SIZE) {
unsigned long addr2;
pgprot_t prot2;
+
addr2 = __START_KERNEL_map + __pa(address);
/* Make sure the kernel mappings stay executable */
prot2 = pte_pgprot(pte_mkexec(pfn_pte(0, prot)));
err = __change_page_attr(addr2, pfn, prot2,
PAGE_KERNEL_EXEC);
- }
- }
- up_write(&init_mm.mmap_sem);
+ }
+ }
+ up_write(&init_mm.mmap_sem);
+
return err;
}
@@ -222,11 +241,13 @@ int change_page_attr_addr(unsigned long address, int numpages, pgprot_t prot)
int change_page_attr(struct page *page, int numpages, pgprot_t prot)
{
unsigned long addr = (unsigned long)page_address(page);
+
return change_page_attr_addr(addr, numpages, prot);
}
+EXPORT_SYMBOL(change_page_attr);
void global_flush_tlb(void)
-{
+{
struct page *pg, *next;
struct list_head l;
@@ -248,8 +269,6 @@ void global_flush_tlb(void)
continue;
ClearPagePrivate(pg);
__free_page(pg);
- }
-}
-
-EXPORT_SYMBOL(change_page_attr);
+ }
+}
EXPORT_SYMBOL(global_flush_tlb);