mm: export stable page flags

Rename get_uflags() to stable_page_flags() and make it a global function
for use in the hwpoison page flags filter, which need to compare user
page flags with the value provided by user space.

Also move KPF_* to kernel-page-flags.h for use by user space tools.

Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
CC: Nick Piggin <npiggin@suse.de>
CC: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
This commit is contained in:
Wu Fengguang 2009-12-16 12:19:59 +01:00 committed by Andi Kleen
parent 31d3d3484f
commit 1a9b5b7fe0
3 changed files with 51 additions and 42 deletions

View file

@ -8,6 +8,7 @@
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/hugetlb.h>
#include <linux/kernel-page-flags.h>
#include <asm/uaccess.h>
#include "internal.h"
@ -71,52 +72,12 @@ static const struct file_operations proc_kpagecount_operations = {
* physical page flags.
*/
/* These macros are used to decouple internal flags from exported ones */
#define KPF_LOCKED 0
#define KPF_ERROR 1
#define KPF_REFERENCED 2
#define KPF_UPTODATE 3
#define KPF_DIRTY 4
#define KPF_LRU 5
#define KPF_ACTIVE 6
#define KPF_SLAB 7
#define KPF_WRITEBACK 8
#define KPF_RECLAIM 9
#define KPF_BUDDY 10
/* 11-20: new additions in 2.6.31 */
#define KPF_MMAP 11
#define KPF_ANON 12
#define KPF_SWAPCACHE 13
#define KPF_SWAPBACKED 14
#define KPF_COMPOUND_HEAD 15
#define KPF_COMPOUND_TAIL 16
#define KPF_HUGE 17
#define KPF_UNEVICTABLE 18
#define KPF_HWPOISON 19
#define KPF_NOPAGE 20
#define KPF_KSM 21
/* kernel hacking assistances
* WARNING: subject to change, never rely on them!
*/
#define KPF_RESERVED 32
#define KPF_MLOCKED 33
#define KPF_MAPPEDTODISK 34
#define KPF_PRIVATE 35
#define KPF_PRIVATE_2 36
#define KPF_OWNER_PRIVATE 37
#define KPF_ARCH 38
#define KPF_UNCACHED 39
static inline u64 kpf_copy_bit(u64 kflags, int ubit, int kbit)
{
return ((kflags >> kbit) & 1) << ubit;
}
static u64 get_uflags(struct page *page)
u64 stable_page_flags(struct page *page)
{
u64 k;
u64 u;
@ -219,7 +180,7 @@ static ssize_t kpageflags_read(struct file *file, char __user *buf,
else
ppage = NULL;
if (put_user(get_uflags(ppage), out)) {
if (put_user(stable_page_flags(ppage), out)) {
ret = -EFAULT;
break;
}

View file

@ -0,0 +1,46 @@
#ifndef LINUX_KERNEL_PAGE_FLAGS_H
#define LINUX_KERNEL_PAGE_FLAGS_H
/*
* Stable page flag bits exported to user space
*/
#define KPF_LOCKED 0
#define KPF_ERROR 1
#define KPF_REFERENCED 2
#define KPF_UPTODATE 3
#define KPF_DIRTY 4
#define KPF_LRU 5
#define KPF_ACTIVE 6
#define KPF_SLAB 7
#define KPF_WRITEBACK 8
#define KPF_RECLAIM 9
#define KPF_BUDDY 10
/* 11-20: new additions in 2.6.31 */
#define KPF_MMAP 11
#define KPF_ANON 12
#define KPF_SWAPCACHE 13
#define KPF_SWAPBACKED 14
#define KPF_COMPOUND_HEAD 15
#define KPF_COMPOUND_TAIL 16
#define KPF_HUGE 17
#define KPF_UNEVICTABLE 18
#define KPF_HWPOISON 19
#define KPF_NOPAGE 20
#define KPF_KSM 21
/* kernel hacking assistances
* WARNING: subject to change, never rely on them!
*/
#define KPF_RESERVED 32
#define KPF_MLOCKED 33
#define KPF_MAPPEDTODISK 34
#define KPF_PRIVATE 35
#define KPF_PRIVATE_2 36
#define KPF_OWNER_PRIVATE 37
#define KPF_ARCH 38
#define KPF_UNCACHED 39
#endif /* LINUX_KERNEL_PAGE_FLAGS_H */

View file

@ -282,6 +282,8 @@ PAGEFLAG_FALSE(HWPoison)
#define __PG_HWPOISON 0
#endif
u64 stable_page_flags(struct page *page);
static inline int PageUptodate(struct page *page)
{
int ret = test_bit(PG_uptodate, &(page)->flags);