[linux-2.6-block.git] / kernel / ksysfs.c

/*
 * kernel/ksysfs.c - sysfs attributes in /sys/kernel, which
 * 		     are not related to any other subsystem
 *
 * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
 * 
 * This file is release under the GPLv2
 *
 */

#include <linux/kobject.h>
#include <linux/string.h>
#include <linux/sysfs.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kexec.h>
#include <linux/sched.h>

#define KERNEL_ATTR_RO(_name) \
static struct subsys_attribute _name##_attr = __ATTR_RO(_name)

#define KERNEL_ATTR_RW(_name) \
static struct subsys_attribute _name##_attr = \
	__ATTR(_name, 0644, _name##_show, _name##_store)

#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
/* current uevent sequence number */
static ssize_t uevent_seqnum_show(struct kset *kset, char *page)
{
	return sprintf(page, "%llu\n", (unsigned long long)uevent_seqnum);
}
KERNEL_ATTR_RO(uevent_seqnum);

/* uevent helper program, used during early boo */
static ssize_t uevent_helper_show(struct kset *kset, char *page)
{
	return sprintf(page, "%s\n", uevent_helper);
}
static ssize_t uevent_helper_store(struct kset *kset, const char *page, size_t count)
{
	if (count+1 > UEVENT_HELPER_PATH_LEN)
		return -ENOENT;
	memcpy(uevent_helper, page, count);
	uevent_helper[count] = '\0';
	if (count && uevent_helper[count-1] == '\n')
		uevent_helper[count-1] = '\0';
	return count;
}
KERNEL_ATTR_RW(uevent_helper);
#endif

#ifdef CONFIG_KEXEC
static ssize_t kexec_loaded_show(struct kset *kset, char *page)
{
	return sprintf(page, "%d\n", !!kexec_image);
}
KERNEL_ATTR_RO(kexec_loaded);

static ssize_t kexec_crash_loaded_show(struct kset *kset, char *page)
{
	return sprintf(page, "%d\n", !!kexec_crash_image);
}
KERNEL_ATTR_RO(kexec_crash_loaded);

static ssize_t vmcoreinfo_show(struct kset *kset, char *page)
{
	return sprintf(page, "%lx %x\n",
		       paddr_vmcoreinfo_note(),
		       (unsigned int)vmcoreinfo_max_size);
}
KERNEL_ATTR_RO(vmcoreinfo);

#endif /* CONFIG_KEXEC */

/*
 * Make /sys/kernel/notes give the raw contents of our kernel .notes section.
 */
extern const void __start_notes __attribute__((weak));
extern const void __stop_notes __attribute__((weak));
#define	notes_size (&__stop_notes - &__start_notes)

static ssize_t notes_read(struct kobject *kobj, struct bin_attribute *bin_attr,
			  char *buf, loff_t off, size_t count)
{
	memcpy(buf, &__start_notes + off, count);
	return count;
}

static struct bin_attribute notes_attr = {
	.attr = {
		.name = "notes",
		.mode = S_IRUGO,
	},
	.read = &notes_read,
};

decl_subsys(kernel, NULL);
EXPORT_SYMBOL_GPL(kernel_subsys);

static struct attribute * kernel_attrs[] = {
#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
	&uevent_seqnum_attr.attr,
	&uevent_helper_attr.attr,
#endif
#ifdef CONFIG_KEXEC
	&kexec_loaded_attr.attr,
	&kexec_crash_loaded_attr.attr,
	&vmcoreinfo_attr.attr,
#endif
	NULL
};

static struct attribute_group kernel_attr_group = {
	.attrs = kernel_attrs,
};

static int __init ksysfs_init(void)
{
	int error = subsystem_register(&kernel_subsys);
	if (!error)
		error = sysfs_create_group(&kernel_subsys.kobj,
					   &kernel_attr_group);

	if (!error && notes_size > 0) {
		notes_attr.size = notes_size;
		error = sysfs_create_bin_file(&kernel_subsys.kobj,
					      &notes_attr);
	}

	/*
	 * Create "/sys/kernel/uids" directory and corresponding root user's
	 * directory under it.
	 */
	if (!error)
		error = uids_kobject_init();

	return error;
}

core_initcall(ksysfs_init);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* kernel/ksysfs.c - sysfs attributes in /sys/kernel, which
	3	* are not related to any other subsystem
	4	*
	5	* Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
	6	*
	7	* This file is release under the GPLv2
	8	*
	9	*/
	10
1da177e4 LT	11	#include <linux/kobject.h>
	12	#include <linux/string.h>
	13	#include <linux/sysfs.h>
	14	#include <linux/module.h>
	15	#include <linux/init.h>
c330dda9	16	#include <linux/kexec.h>
5cb350ba	17	#include <linux/sched.h>
1da177e4 LT	18
	19	#define KERNEL_ATTR_RO(_name) \
	20	static struct subsys_attribute _name##_attr = __ATTR_RO(_name)
	21
	22	#define KERNEL_ATTR_RW(_name) \
	23	static struct subsys_attribute _name##_attr = \
	24	__ATTR(_name, 0644, _name##_show, _name##_store)
	25
f125b561	26	#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
0f76e5ac	27	/* current uevent sequence number */
823bccfc	28	static ssize_t uevent_seqnum_show(struct kset kset, char page)
1da177e4	29	{
312c004d	30	return sprintf(page, "%llu\n", (unsigned long long)uevent_seqnum);
1da177e4	31	}
0f76e5ac KS	32	KERNEL_ATTR_RO(uevent_seqnum);
	33
	34	/* uevent helper program, used during early boo */
823bccfc	35	static ssize_t uevent_helper_show(struct kset kset, char page)
0f76e5ac	36	{
312c004d	37	return sprintf(page, "%s\n", uevent_helper);
0f76e5ac	38	}
823bccfc	39	static ssize_t uevent_helper_store(struct kset kset, const char page, size_t count)
0f76e5ac	40	{
312c004d	41	if (count+1 > UEVENT_HELPER_PATH_LEN)
0f76e5ac	42	return -ENOENT;
312c004d KS	43	memcpy(uevent_helper, page, count);
	44	uevent_helper[count] = '\0';
	45	if (count && uevent_helper[count-1] == '\n')
	46	uevent_helper[count-1] = '\0';
0f76e5ac KS	47	return count;
	48	}
	49	KERNEL_ATTR_RW(uevent_helper);
1da177e4 LT	50	#endif
1da177e4 LT	51
c330dda9	52	#ifdef CONFIG_KEXEC
823bccfc	53	static ssize_t kexec_loaded_show(struct kset kset, char page)
c330dda9 JM	54	{
	55	return sprintf(page, "%d\n", !!kexec_image);
	56	}
	57	KERNEL_ATTR_RO(kexec_loaded);
	58
823bccfc	59	static ssize_t kexec_crash_loaded_show(struct kset kset, char page)
c330dda9 JM	60	{
	61	return sprintf(page, "%d\n", !!kexec_crash_image);
	62	}
	63	KERNEL_ATTR_RO(kexec_crash_loaded);
fd59d231 KO	64
	65	static ssize_t vmcoreinfo_show(struct kset kset, char page)
	66	{
	67	return sprintf(page, "%lx %x\n",
	68	paddr_vmcoreinfo_note(),
d768281e	69	(unsigned int)vmcoreinfo_max_size);
fd59d231 KO	70	}
	71	KERNEL_ATTR_RO(vmcoreinfo);
	72
c330dda9 JM	73	#endif /* CONFIG_KEXEC */
c330dda9 JM	74
da1a679c RM	75	/*
	76	* Make /sys/kernel/notes give the raw contents of our kernel .notes section.
	77	*/
0b1937ac DH	78	extern const void __start_notes __attribute__((weak));
0b1937ac DH	79	extern const void __stop_notes __attribute__((weak));
da1a679c RM	80	#define notes_size (&__stop_notes - &__start_notes)
	81
	82	static ssize_t notes_read(struct kobject kobj, struct bin_attribute bin_attr,
	83	char *buf, loff_t off, size_t count)
	84	{
	85	memcpy(buf, &__start_notes + off, count);
	86	return count;
	87	}
	88
	89	static struct bin_attribute notes_attr = {
	90	.attr = {
	91	.name = "notes",
	92	.mode = S_IRUGO,
	93	},
	94	.read = &notes_read,
	95	};
	96
3514faca	97	decl_subsys(kernel, NULL);
1da177e4 LT	98	EXPORT_SYMBOL_GPL(kernel_subsys);
	99
	100	static struct attribute * kernel_attrs[] = {
f125b561	101	#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
0f76e5ac KS	102	&uevent_seqnum_attr.attr,
0f76e5ac KS	103	&uevent_helper_attr.attr,
c330dda9 JM	104	#endif
	105	#ifdef CONFIG_KEXEC
	106	&kexec_loaded_attr.attr,
	107	&kexec_crash_loaded_attr.attr,
fd59d231	108	&vmcoreinfo_attr.attr,
1da177e4 LT	109	#endif
	110	NULL
	111	};
	112
	113	static struct attribute_group kernel_attr_group = {
	114	.attrs = kernel_attrs,
	115	};
	116
	117	static int __init ksysfs_init(void)
	118	{
	119	int error = subsystem_register(&kernel_subsys);
	120	if (!error)
823bccfc	121	error = sysfs_create_group(&kernel_subsys.kobj,
1da177e4 LT	122	&kernel_attr_group);
1da177e4 LT	123
da1a679c RM	124	if (!error && notes_size > 0) {
	125	notes_attr.size = notes_size;
	126	error = sysfs_create_bin_file(&kernel_subsys.kobj,
	127	&notes_attr);
	128	}
	129
5cb350ba DG	130	/*
	131	* Create "/sys/kernel/uids" directory and corresponding root user's
	132	* directory under it.
	133	*/
	134	if (!error)
	135	error = uids_kobject_init();
	136
1da177e4 LT	137	return error;
	138	}
	139
	140	core_initcall(ksysfs_init);