[PATCH] x86: fix change_page_attr() TLB and cache flushing

From: Jan Beulich
Date: Tue Jun 12 2007 - 03:35:50 EST


change_page_attr() failed to flush the caches for the affected pages
for quite a while, and on x86-64 only recently got a brute-force fix to
flush the entire TLB (which now gets reduced to just the affected pages
when possible).

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>

arch/i386/mm/ioremap.c | 4
arch/i386/mm/pageattr.c | 181 +++++++++++++++++++++++++++-----------
arch/x86_64/mm/ioremap.c | 6 -
arch/x86_64/mm/pageattr.c | 202 ++++++++++++++++++++++++++++++-------------
include/asm-i386/page.h | 10 ++
include/asm-i386/pgtable.h | 3
include/asm-x86_64/page.h | 2
include/asm-x86_64/pgtable.h | 4
include/asm-x86_64/system.h | 2
9 files changed, 292 insertions(+), 122 deletions(-)

--- linux-2.6.22-rc4/arch/i386/mm/ioremap.c 2007-04-26 05:08:32.000000000 +0200
+++ 2.6.22-rc4-x86-change_page_attr/arch/i386/mm/ioremap.c 2007-06-11 09:13:57.000000000 +0200
@@ -193,10 +193,10 @@ void iounmap(volatile void __iomem *addr
return;
}

- /* Reset the direct mapping. Can block */
+ /* Reset the direct mapping. Can block. Heed the trailing guard page. */
if ((p->flags >> 20) && p->phys_addr < virt_to_phys(high_memory) - 1) {
change_page_attr(virt_to_page(__va(p->phys_addr)),
- p->size >> PAGE_SHIFT,
+ (p->size >> PAGE_SHIFT) - 1,
PAGE_KERNEL);
global_flush_tlb();
}
--- linux-2.6.22-rc4/arch/i386/mm/pageattr.c 2007-06-11 18:09:52.000000000 +0200
+++ 2.6.22-rc4-x86-change_page_attr/arch/i386/mm/pageattr.c 2007-06-11 09:13:57.000000000 +0200
@@ -16,7 +16,29 @@

static DEFINE_SPINLOCK(cpa_lock);
static struct list_head df_list = LIST_HEAD_INIT(df_list);
+static struct df_info {
+ unsigned long address;
+ int count;
+} deferred[2];
+#define TLB 0
+#define CACHE 1

+static inline void update_deferred(struct df_info *df,
+ unsigned long address, int count)
+{
+ if (df->count == 0) {
+ df->address = address;
+ df->count = count;
+ } else if (df->count > 0) {
+ if (df->address + (df->count << PAGE_SHIFT) == address)
+ df->count += count;
+ else if (address + (count << PAGE_SHIFT) == df->address) {
+ df->address = address;
+ df->count += count;
+ } else
+ df->count = -1;
+ }
+}

pte_t *lookup_address(unsigned long address)
{
@@ -70,19 +92,29 @@ static struct page *split_large_page(uns

static void flush_kernel_map(void *arg)
{
- unsigned long adr = (unsigned long)arg;
-
- if (adr && cpu_has_clflush) {
- int i;
- for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size)
- asm volatile("clflush (%0)" :: "r" (adr + i));
- } else if (boot_cpu_data.x86_model >= 4)
- wbinvd();
+ const struct df_info *info = arg;

/* Flush all to work around Errata in early athlons regarding
* large page flushing.
*/
__flush_tlb_all();
+
+ if (info[CACHE].count != 0 && boot_cpu_data.x86_model >= 4) {
+ if (info[CACHE].count < 0)
+ wbinvd();
+ else {
+ unsigned long addr = info[CACHE].address;
+ int count = info[CACHE].count;
+
+ while (count-- > 0) {
+ int i;
+
+ for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size)
+ asm volatile("clflush (%0)" :: "r" (addr + i));
+ addr += PAGE_SIZE;
+ }
+ }
+ }
}

static void set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
@@ -107,32 +139,39 @@ static void set_pmd_pte(pte_t *kpte, uns
spin_unlock_irqrestore(&pgd_lock, flags);
}

+static pgprot_t _ref_prot[KERNEL_PGD_PTRS * PTRS_PER_PMD];
+#define ref_prot(addr) _ref_prot[__pa(addr) >> PMD_SHIFT]
+
/*
* 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)
{
- pgprot_t ref_prot;
pte_t *linear;

- ref_prot =
- ((address & LARGE_PAGE_MASK) < (unsigned long)&_etext)
- ? PAGE_KERNEL_LARGE_EXEC : PAGE_KERNEL_LARGE;
-
linear = (pte_t *)
pmd_offset(pud_offset(pgd_offset_k(address), address), address);
set_pmd_pte(linear, address,
- pfn_pte((__pa(address) & LARGE_PAGE_MASK) >> PAGE_SHIFT,
- ref_prot));
+ pte_mkhuge(pfn_pte((__pa(address) & LARGE_PAGE_MASK) >> PAGE_SHIFT,
+ ref_prot(address))));
}

-static int
-__change_page_attr(struct page *page, pgprot_t prot)
+static inline int pgprot_match(pgprot_t prot1, pgprot_t prot2)
+{
+ return !((pgprot_val(prot1) ^ pgprot_val(prot2))
+#ifdef CONFIG_X86_PAE
+ & __supported_pte_mask
+#endif
+ & ~(_PAGE_ACCESSED|_PAGE_DIRTY));
+}
+
+static int __change_page_attr(struct page *page, pgprot_t prot)
{
pte_t *kpte;
unsigned long address;
struct page *kpte_page;
+ pgprot_t old_prot, ref_prot;

BUG_ON(PageHighMem(page));
address = (unsigned long)page_address(page);
@@ -141,37 +180,55 @@ __change_page_attr(struct page *page, pg
if (!kpte)
return -EINVAL;
kpte_page = virt_to_page(kpte);
- if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL)) {
+ old_prot = pte_pgprot(pte_clrhuge(*kpte));
+ ref_prot = ref_prot(address);
+ if (!pgprot_match(prot, ref_prot)) {
if (!pte_huge(*kpte)) {
set_pte_atomic(kpte, mk_pte(page, prot));
} else {
- pgprot_t ref_prot;
- struct page *split;
-
- ref_prot =
- ((address & LARGE_PAGE_MASK) < (unsigned long)&_etext)
- ? PAGE_KERNEL_EXEC : PAGE_KERNEL;
- split = split_large_page(address, prot, ref_prot);
- if (!split)
+ BUG_ON(!pgprot_match(old_prot, ref_prot));
+ kpte_page = split_large_page(address, prot, ref_prot);
+ if (!kpte_page)
return -ENOMEM;
- set_pmd_pte(kpte,address,mk_pte(split, ref_prot));
- kpte_page = split;
+ set_pmd_pte(kpte, address,
+ mk_pte(kpte_page, PAGE_KERNEL_EXEC));
+ }
+ if (!PageReserved(kpte_page)
+ && pgprot_match(old_prot, ref_prot))
+ page_private(kpte_page)++;
+ } else if (!pgprot_match(ref_prot, old_prot)) {
+ BUG_ON(pte_huge(*kpte));
+ set_pte_atomic(kpte, mk_pte(page, ref_prot));
+ if (!PageReserved(kpte_page)) {
+ BUG_ON(page_private(kpte_page) == 0);
+ page_private(kpte_page)--;
}
- 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();
+ return 0;
+
+ if ((pgprot_val(prot) ^ pgprot_val(old_prot)) & (_PAGE_PCD|_PAGE_PWT)) {
+ if (!cpu_has_clflush || !pte_present(pfn_pte(0, prot)))
+ deferred[CACHE].count = -1;
+ else
+ update_deferred(deferred + CACHE, address, 1);
+ }

/*
* If the pte was reserved, it means it was created at boot
* time (not via split_large_page) and in turn we must not
* replace it with a largepage.
*/
- if (!PageReserved(kpte_page)) {
- if (cpu_has_pse && (page_private(kpte_page) == 0)) {
+ if (!PageReserved(kpte_page) && cpu_has_pse) {
+ if (page_private(kpte_page) == PTRS_PER_PTE) {
+ unsigned i;
+
+ kpte = page_address(kpte_page);
+ for (i = 0; i < PTRS_PER_PTE; ++i, ++kpte)
+ if (pgprot_match(pte_pgprot(*kpte), prot))
+ page_private(kpte_page)--;
+ ref_prot(address) = prot;
+ }
+ if (page_private(kpte_page) == 0) {
ClearPagePrivate(kpte_page);
paravirt_release_pt(page_to_pfn(kpte_page));
list_add(&kpte_page->lru, &df_list);
@@ -181,13 +238,8 @@ __change_page_attr(struct page *page, pg
return 0;
}

-static inline void flush_map(void *adr)
-{
- on_each_cpu(flush_kernel_map, adr, 1, 1);
-}
-
/*
- * Change the page attributes of an page in the linear mapping.
+ * Change the page attributes of a page in the linear mapping.
*
* This should be used when a page is mapped with a different caching policy
* than write-back somewhere - some CPUs do not like it when mappings with
@@ -204,34 +256,59 @@ int change_page_attr(struct page *page,
int err = 0;
int i;
unsigned long flags;
+ struct list_head l;
+ struct page *next;
+ static char first = 1;

spin_lock_irqsave(&cpa_lock, flags);
+
+ if (unlikely(first)) {
+ unsigned long addr = PAGE_OFFSET & PMD_MASK;
+
+ /* This must match is_kernel_text(). */
+ for (; addr <= (unsigned long)__init_end; addr += PMD_SIZE)
+ ref_prot(addr) = PAGE_KERNEL_EXEC;
+ for (; addr > PAGE_OFFSET; addr += PMD_SIZE)
+ ref_prot(addr) = PAGE_KERNEL;
+ first = 0;
+ }
+
+ /* No need to call update_deferred() as long flush_kernel_map()
+ * uses __flush_tlb_all(). */
+ deferred[TLB].count = -1;
+
for (i = 0; i < numpages; i++, page++) {
err = __change_page_attr(page, prot);
if (err)
break;
}
+
+ list_replace_init(&df_list, &l);
+
spin_unlock_irqrestore(&cpa_lock, flags);
+
+ list_for_each_entry_safe(page, next, &l, lru)
+ __free_page(page);
+
return err;
}

void global_flush_tlb(void)
{
- struct list_head l;
- struct page *pg, *next;
+ unsigned i;
+ struct df_info info[ARRAY_SIZE(deferred)];

BUG_ON(irqs_disabled());

spin_lock_irq(&cpa_lock);
- list_replace_init(&df_list, &l);
- spin_unlock_irq(&cpa_lock);
- if (!cpu_has_clflush)
- flush_map(NULL);
- list_for_each_entry_safe(pg, next, &l, lru) {
- if (cpu_has_clflush)
- flush_map(page_address(pg));
- __free_page(pg);
+ for (i = 0; i < ARRAY_SIZE(info); ++i) {
+ info[i] = deferred[i];
+ deferred[i].count = 0;
}
+ spin_unlock_irq(&cpa_lock);
+
+ if (info[TLB].count)
+ on_each_cpu(flush_kernel_map, info, 1, 1);
}

#ifdef CONFIG_DEBUG_PAGEALLOC
--- linux-2.6.22-rc4/arch/x86_64/mm/ioremap.c 2007-06-11 18:10:04.000000000 +0200
+++ 2.6.22-rc4-x86-change_page_attr/arch/x86_64/mm/ioremap.c 2007-06-11 09:13:57.000000000 +0200
@@ -48,7 +48,7 @@ ioremap_change_attr(unsigned long phys_a
* Must use a address here and not struct page because the phys addr
* can be a in hole between nodes and not have an memmap entry.
*/
- err = change_page_attr_addr(vaddr,npages,__pgprot(__PAGE_KERNEL|flags));
+ err = change_page_attr_addr(vaddr,npages,MAKE_GLOBAL(__PAGE_KERNEL|flags));
if (!err)
global_flush_tlb();
}
@@ -197,9 +197,9 @@ void iounmap(volatile void __iomem *addr
return;
}

- /* Reset the direct mapping. Can block */
+ /* Reset the direct mapping. Can block. Heed the trailing guard page. */
if (p->flags >> 20)
- ioremap_change_attr(p->phys_addr, p->size, 0);
+ ioremap_change_attr(p->phys_addr, p->size - PAGE_SIZE, 0);

/* Finally remove it */
o = remove_vm_area((void *)addr);
--- linux-2.6.22-rc4/arch/x86_64/mm/pageattr.c 2007-06-11 18:10:04.000000000 +0200
+++ 2.6.22-rc4-x86-change_page_attr/arch/x86_64/mm/pageattr.c 2007-06-11 09:13:57.000000000 +0200
@@ -61,7 +61,31 @@ static struct page *split_large_page(uns
return base;
}

-static void cache_flush_page(void *adr)
+struct deferred_info {
+ unsigned long address;
+ int count;
+};
+#define TLB 0
+#define CACHE 1
+
+static inline void update_deferred(struct deferred_info *df,
+ unsigned long address, int count)
+{
+ if (df->count == 0) {
+ df->address = address;
+ df->count = count;
+ } else if (df->count > 0) {
+ if (df->address + (df->count << PAGE_SHIFT) == address)
+ df->count += count;
+ else if (address + (count << PAGE_SHIFT) == df->address) {
+ df->address = address;
+ df->count += count;
+ } else
+ df->count = -1;
+ }
+}
+
+static inline void cache_flush_page(unsigned long adr)
{
int i;
for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size)
@@ -70,38 +94,60 @@ static void cache_flush_page(void *adr)

static void flush_kernel_map(void *arg)
{
- struct list_head *l = (struct list_head *)arg;
- struct page *pg;
+ const struct deferred_info *info = arg;
+
+ if (info[TLB].count < 0)
+ __flush_tlb_all();
+ else {
+ unsigned long addr = info[TLB].address;
+ int count = info[TLB].count;
+
+ while (count-- > 0) {
+ __flush_tlb_one(addr);
+ if (__pa(addr) < KERNEL_TEXT_SIZE)
+ __flush_tlb_one(__START_KERNEL_map + __pa(addr));
+ addr += PAGE_SIZE;
+ }
+ }

+ if (info[CACHE].count == 0)
+ ;
/* When clflush is available always use it because it is
much cheaper than WBINVD */
- if (!cpu_has_clflush)
- asm volatile("wbinvd" ::: "memory");
- list_for_each_entry(pg, l, lru) {
- void *adr = page_address(pg);
- if (cpu_has_clflush)
- cache_flush_page(adr);
+ else if (info[CACHE].count < 0)
+ wbinvd();
+ else {
+ unsigned long addr = info[CACHE].address;
+ int count = info[CACHE].count;
+
+ BUG_ON(!cpu_has_clflush);
+ while (count-- > 0) {
+ cache_flush_page(addr);
+ if (__pa(addr) < KERNEL_TEXT_SIZE) {
+ unsigned long kaddr = __START_KERNEL_map + __pa(addr);
+
+ if (lookup_address(kaddr))
+ cache_flush_page(kaddr);
+ }
+ addr += PAGE_SIZE;
+ }
}
- __flush_tlb_all();
}

-static inline void flush_map(struct list_head *l)
-{
- on_each_cpu(flush_kernel_map, l, 1, 1);
-}
-
-static LIST_HEAD(deferred_pages); /* protected by init_mm.mmap_sem */
-
-static inline void save_page(struct page *fpage)
-{
- list_add(&fpage->lru, &deferred_pages);
-}
+/* protected by init_mm.mmap_sem */
+static LIST_HEAD(deferred_pages);
+static struct deferred_info deferred[2];
+static pgprot_t kref_prot[] = {
+ [0 ... (KERNEL_TEXT_SIZE - 1) >> PMD_SHIFT] = PAGE_KERNEL_EXEC
+};
+#define kref_prot(kaddr) kref_prot[((kaddr) - __START_KERNEL_map) >> PMD_SHIFT]

/*
- * No more special protections in this 2/4MB area - revert to a
+ * No more special protections in this 2MB area - revert to a
* large page again.
*/
-static void revert_page(unsigned long address, pgprot_t ref_prot)
+static void revert_page(struct page *kpte_page, unsigned long address,
+ pgprot_t ref_prot)
{
pgd_t *pgd;
pud_t *pud;
@@ -109,6 +155,8 @@ static void revert_page(unsigned long ad
pte_t large_pte;
unsigned long pfn;

+ list_add(&kpte_page->lru, &deferred_pages);
+
pgd = pgd_offset_k(address);
BUG_ON(pgd_none(*pgd));
pud = pud_offset(pgd,address);
@@ -121,52 +169,71 @@ static void revert_page(unsigned long ad
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)
+static inline int pgprot_match(pgprot_t prot1, pgprot_t prot2)
+{
+ return !((pgprot_val(prot1) ^ pgprot_val(prot2))
+ & __supported_pte_mask & ~(_PAGE_ACCESSED|_PAGE_DIRTY));
+}
+
+static int __change_page_attr(unsigned long address, unsigned long pfn,
+ pgprot_t prot, pgprot_t ref_prot)
{
- pte_t *kpte;
+ pte_t *kpte = lookup_address(address);
struct page *kpte_page;
- pgprot_t ref_prot2;
- kpte = lookup_address(address);
+ pgprot_t old_prot;
+
if (!kpte) return 0;
- kpte_page = virt_to_page(((unsigned long)kpte) & PAGE_MASK);
- if (pgprot_val(prot) != pgprot_val(ref_prot)) {
+ kpte_page = virt_to_page(kpte);
+ old_prot = pte_pgprot(pte_clrhuge(*kpte));
+ if (!pgprot_match(prot, 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)
+ BUG_ON(!pgprot_match(old_prot, ref_prot));
+ kpte_page = split_large_page(address, prot, ref_prot);
+ if (!kpte_page)
return -ENOMEM;
- set_pte(kpte, mk_pte(split, ref_prot2));
- kpte_page = split;
+ set_pte(kpte, mk_pte(kpte_page, PAGE_KERNEL_EXEC));
}
- page_private(kpte_page)++;
- } else if (!pte_huge(*kpte)) {
+ if (pgprot_match(old_prot, ref_prot))
+ page_private(kpte_page)++;
+ } else if (!pgprot_match(ref_prot, old_prot)) {
+ BUG_ON(pte_huge(*kpte));
set_pte(kpte, pfn_pte(pfn, ref_prot));
BUG_ON(page_private(kpte_page) == 0);
page_private(kpte_page)--;
} else
- BUG();
+ return 0;
+
+ if ((pgprot_val(prot) ^ pgprot_val(old_prot)) & (_PAGE_PCD|_PAGE_PWT)) {
+ if (!cpu_has_clflush || !pte_present(pfn_pte(0, prot)))
+ deferred[CACHE].count = -1;
+ else
+ update_deferred(deferred + CACHE, address, 1);
+ }

/* on x86-64 the direct mapping set at boot is not using 4k pages */
BUG_ON(PageReserved(kpte_page));

- if (page_private(kpte_page) == 0) {
- save_page(kpte_page);
- revert_page(address, ref_prot);
- }
+ if (page_private(kpte_page) == PTRS_PER_PTE
+ && address >= __START_KERNEL_map
+ && address < __START_KERNEL_map + KERNEL_TEXT_SIZE) {
+ unsigned i;
+
+ kpte = page_address(kpte_page);
+ for (i = 0; i < PTRS_PER_PTE; ++i, ++kpte)
+ if (pgprot_match(pte_pgprot(*kpte), prot))
+ page_private(kpte_page)--;
+ kref_prot(address) = ref_prot = prot;
+ }
+ if (page_private(kpte_page) == 0)
+ revert_page(kpte_page, address, ref_prot);
+
return 0;
}

/*
- * Change the page attributes of an page in the linear mapping.
+ * Change the page attributes of a page in the linear mapping.
*
* This should be used when a page is mapped with a different caching policy
* than write-back somewhere - some CPUs do not like it when mappings with
@@ -182,6 +249,8 @@ int change_page_attr_addr(unsigned long
{
int err = 0, kernel_map = 0;
int i;
+ struct page *pg, *next;
+ struct list_head l;

if (address >= __START_KERNEL_map
&& address < __START_KERNEL_map + KERNEL_TEXT_SIZE) {
@@ -190,6 +259,9 @@ int change_page_attr_addr(unsigned long
}

down_write(&init_mm.mmap_sem);
+
+ update_deferred(deferred + TLB, address, numpages);
+
for (i = 0; i < numpages; i++, address += PAGE_SIZE) {
unsigned long pfn = __pa(address) >> PAGE_SHIFT;

@@ -207,10 +279,19 @@ int change_page_attr_addr(unsigned long
/* 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);
+ kref_prot(addr2));
}
}
+
+ list_replace_init(&deferred_pages, &l);
+
up_write(&init_mm.mmap_sem);
+
+ list_for_each_entry_safe(pg, next, &l, lru) {
+ ClearPagePrivate(pg);
+ __free_page(pg);
+ }
+
return err;
}

@@ -223,19 +304,18 @@ int change_page_attr(struct page *page,

void global_flush_tlb(void)
{
- struct page *pg, *next;
- struct list_head l;
-
- down_read(&init_mm.mmap_sem);
- list_replace_init(&deferred_pages, &l);
- up_read(&init_mm.mmap_sem);
+ unsigned i;
+ struct deferred_info info[ARRAY_SIZE(deferred)];

- flush_map(&l);
+ down_write(&init_mm.mmap_sem);
+ for (i = 0; i < ARRAY_SIZE(info); ++i) {
+ info[i] = deferred[i];
+ deferred[i].count = 0;
+ }
+ up_write(&init_mm.mmap_sem);

- list_for_each_entry_safe(pg, next, &l, lru) {
- ClearPagePrivate(pg);
- __free_page(pg);
- }
+ if (info[TLB].count)
+ on_each_cpu(flush_kernel_map, info, 1, 1);
}

EXPORT_SYMBOL(change_page_attr);
--- linux-2.6.22-rc4/include/asm-i386/page.h 2007-06-11 18:10:43.000000000 +0200
+++ 2.6.22-rc4-x86-change_page_attr/include/asm-i386/page.h 2007-06-11 09:13:57.000000000 +0200
@@ -6,6 +6,16 @@
#define PAGE_SIZE (1UL << PAGE_SHIFT)
#define PAGE_MASK (~(PAGE_SIZE-1))

+#ifdef CONFIG_X86_PAE
+#define __PHYSICAL_MASK_SHIFT 52
+#define __PHYSICAL_MASK ((1ULL << __PHYSICAL_MASK_SHIFT) - 1)
+#define PHYSICAL_PAGE_MASK (~(PAGE_SIZE - 1ULL) & __PHYSICAL_MASK)
+#else
+#define __PHYSICAL_MASK_SHIFT 32
+#define __PHYSICAL_MASK (~0UL)
+#define PHYSICAL_PAGE_MASK (PAGE_MASK & __PHYSICAL_MASK)
+#endif
+
#define LARGE_PAGE_MASK (~(LARGE_PAGE_SIZE-1))
#define LARGE_PAGE_SIZE (1UL << PMD_SHIFT)

--- linux-2.6.22-rc4/include/asm-i386/pgtable.h 2007-06-11 18:10:43.000000000 +0200
+++ 2.6.22-rc4-x86-change_page_attr/include/asm-i386/pgtable.h 2007-06-11 09:13:57.000000000 +0200
@@ -235,6 +235,7 @@ static inline pte_t pte_exprotect(pte_t
static inline pte_t pte_mkclean(pte_t pte) { (pte).pte_low &= ~_PAGE_DIRTY; return pte; }
static inline pte_t pte_mkold(pte_t pte) { (pte).pte_low &= ~_PAGE_ACCESSED; return pte; }
static inline pte_t pte_wrprotect(pte_t pte) { (pte).pte_low &= ~_PAGE_RW; return pte; }
+static inline pte_t pte_clrhuge(pte_t pte) { (pte).pte_low &= ~_PAGE_PSE; return pte; }
static inline pte_t pte_mkread(pte_t pte) { (pte).pte_low |= _PAGE_USER; return pte; }
static inline pte_t pte_mkexec(pte_t pte) { (pte).pte_low |= _PAGE_USER; return pte; }
static inline pte_t pte_mkdirty(pte_t pte) { (pte).pte_low |= _PAGE_DIRTY; return pte; }
@@ -242,6 +243,8 @@ static inline pte_t pte_mkyoung(pte_t pt
static inline pte_t pte_mkwrite(pte_t pte) { (pte).pte_low |= _PAGE_RW; return pte; }
static inline pte_t pte_mkhuge(pte_t pte) { (pte).pte_low |= _PAGE_PSE; return pte; }

+#define pte_pgprot(pte) (__pgprot(pte_val(pte) & ~PHYSICAL_PAGE_MASK))
+
#ifdef CONFIG_X86_PAE
# include <asm/pgtable-3level.h>
#else
--- linux-2.6.22-rc4/include/asm-x86_64/page.h 2007-06-11 18:10:48.000000000 +0200
+++ 2.6.22-rc4-x86-change_page_attr/include/asm-x86_64/page.h 2007-06-11 09:13:57.000000000 +0200
@@ -97,7 +97,7 @@ extern unsigned long phys_base;
#define PAGE_ALIGN(addr) (((addr)+PAGE_SIZE-1)&PAGE_MASK)

/* See Documentation/x86_64/mm.txt for a description of the memory map. */
-#define __PHYSICAL_MASK_SHIFT 46
+#define __PHYSICAL_MASK_SHIFT 52
#define __PHYSICAL_MASK ((_AC(1,UL) << __PHYSICAL_MASK_SHIFT) - 1)
#define __VIRTUAL_MASK_SHIFT 48
#define __VIRTUAL_MASK ((_AC(1,UL) << __VIRTUAL_MASK_SHIFT) - 1)
--- linux-2.6.22-rc4/include/asm-x86_64/pgtable.h 2007-06-11 18:10:48.000000000 +0200
+++ 2.6.22-rc4-x86-change_page_attr/include/asm-x86_64/pgtable.h 2007-06-11 09:13:57.000000000 +0200
@@ -356,9 +356,9 @@ static inline int pmd_large(pmd_t pte) {
#define pfn_pmd(nr,prot) (__pmd(((nr) << PAGE_SHIFT) | pgprot_val(prot)))
#define pmd_pfn(x) ((pmd_val(x) & __PHYSICAL_MASK) >> PAGE_SHIFT)

-#define pte_to_pgoff(pte) ((pte_val(pte) & PHYSICAL_PAGE_MASK) >> PAGE_SHIFT)
+#define pte_to_pgoff(pte) (pte_val(pte) >> PAGE_SHIFT)
#define pgoff_to_pte(off) ((pte_t) { ((off) << PAGE_SHIFT) | _PAGE_FILE })
-#define PTE_FILE_MAX_BITS __PHYSICAL_MASK_SHIFT
+#define PTE_FILE_MAX_BITS (64 - PAGE_SHIFT)

/* PTE - Level 1 access. */

--- linux-2.6.22-rc4/include/asm-x86_64/system.h 2007-06-11 18:10:48.000000000 +0200
+++ 2.6.22-rc4-x86-change_page_attr/include/asm-x86_64/system.h 2007-06-11 09:13:57.000000000 +0200
@@ -109,7 +109,7 @@ static inline void write_cr4(unsigned lo
#define stts() write_cr0(8 | read_cr0())

#define wbinvd() \
- __asm__ __volatile__ ("wbinvd": : :"memory");
+ __asm__ __volatile__ ("wbinvd": : :"memory")

/*
* On SMP systems, when the scheduler does migration-cost autodetection,


-
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