sysdev: fix prototype for memory_sysdev_class show/store functions

The function prototype mismatches in call stack:

                [<ffffffff81494268>] print_block_size+0x58/0x60
                [<ffffffff81487e3f>] sysdev_class_show+0x1f/0x30
                [<ffffffff811d629b>] sysfs_read_file+0xcb/0x1f0
                [<ffffffff81176328>] vfs_read+0xc8/0x180

Due to prototype mismatch, print_block_size() will sprintf() into
*attribute instead of *buf, hence user space will read the initial
zeros from *buf:
	$ hexdump /sys/devices/system/memory/block_size_bytes
	0000000 0000 0000 0000 0000
	0000008

After patch:
	cat /sys/devices/system/memory/block_size_bytes
	0x8000000

This complements commits c29af9636 and 4a0b2b4dbe.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: "Zheng, Shaohui" <shaohui.zheng@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Wu Fengguang 2010-01-15 17:01:32 -08:00 committed by Linus Torvalds
parent ba168fc37d
commit 8ff410daa0

View File

@ -309,17 +309,19 @@ static SYSDEV_ATTR(removable, 0444, show_mem_removable, NULL);
* Block size attribute stuff
*/
static ssize_t
print_block_size(struct class *class, char *buf)
print_block_size(struct sysdev_class *class,
struct sysdev_class_attribute *class_attr,
char *buf)
{
return sprintf(buf, "%#lx\n", (unsigned long)PAGES_PER_SECTION * PAGE_SIZE);
}
static CLASS_ATTR(block_size_bytes, 0444, print_block_size, NULL);
static SYSDEV_CLASS_ATTR(block_size_bytes, 0444, print_block_size, NULL);
static int block_size_init(void)
{
return sysfs_create_file(&memory_sysdev_class.kset.kobj,
&class_attr_block_size_bytes.attr);
&attr_block_size_bytes.attr);
}
/*
@ -330,7 +332,9 @@ static int block_size_init(void)
*/
#ifdef CONFIG_ARCH_MEMORY_PROBE
static ssize_t
memory_probe_store(struct class *class, const char *buf, size_t count)
memory_probe_store(struct sysdev_class *class,
struct sysdev_class_attribute *class_attr,
const char *buf, size_t count)
{
u64 phys_addr;
int nid;
@ -346,12 +350,12 @@ memory_probe_store(struct class *class, const char *buf, size_t count)
return count;
}
static CLASS_ATTR(probe, S_IWUSR, NULL, memory_probe_store);
static SYSDEV_CLASS_ATTR(probe, S_IWUSR, NULL, memory_probe_store);
static int memory_probe_init(void)
{
return sysfs_create_file(&memory_sysdev_class.kset.kobj,
&class_attr_probe.attr);
&attr_probe.attr);
}
#else
static inline int memory_probe_init(void)
@ -367,7 +371,9 @@ static inline int memory_probe_init(void)
/* Soft offline a page */
static ssize_t
store_soft_offline_page(struct class *class, const char *buf, size_t count)
store_soft_offline_page(struct sysdev_class *class,
struct sysdev_class_attribute *class_attr,
const char *buf, size_t count)
{
int ret;
u64 pfn;
@ -384,7 +390,9 @@ store_soft_offline_page(struct class *class, const char *buf, size_t count)
/* Forcibly offline a page, including killing processes. */
static ssize_t
store_hard_offline_page(struct class *class, const char *buf, size_t count)
store_hard_offline_page(struct sysdev_class *class,
struct sysdev_class_attribute *class_attr,
const char *buf, size_t count)
{
int ret;
u64 pfn;
@ -397,18 +405,18 @@ store_hard_offline_page(struct class *class, const char *buf, size_t count)
return ret ? ret : count;
}
static CLASS_ATTR(soft_offline_page, 0644, NULL, store_soft_offline_page);
static CLASS_ATTR(hard_offline_page, 0644, NULL, store_hard_offline_page);
static SYSDEV_CLASS_ATTR(soft_offline_page, 0644, NULL, store_soft_offline_page);
static SYSDEV_CLASS_ATTR(hard_offline_page, 0644, NULL, store_hard_offline_page);
static __init int memory_fail_init(void)
{
int err;
err = sysfs_create_file(&memory_sysdev_class.kset.kobj,
&class_attr_soft_offline_page.attr);
&attr_soft_offline_page.attr);
if (!err)
err = sysfs_create_file(&memory_sysdev_class.kset.kobj,
&class_attr_hard_offline_page.attr);
&attr_hard_offline_page.attr);
return err;
}
#else