0f76e5acf9
This deprecates the /proc/sys/kernel/hotplug file, as all this stuff should be in /sys some day, right? :) In /sys/kernel/ we have now uevent_seqnum and uevent_helper. The seqnum is no longer used by udev, as the version for this kernel depends on netlink which events will never get out-of-order. Recent udev versions disable the /sbin/hotplug helper with an init script, cause it leads to OOM on big boxes by running hundreds of shells in parallel. It should be done now by: echo "" > /sys/kernel/uevent_helper (Note that "-n" does not work, cause neighter proc nor sysfs support truncate().) Signed-off-by: Kay Sievers <kay.sievers@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
90 lines
2.1 KiB
C
90 lines
2.1 KiB
C
/*
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* kernel/ksysfs.c - sysfs attributes in /sys/kernel, which
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* are not related to any other subsystem
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*
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* Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
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*
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* This file is release under the GPLv2
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*
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*/
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#include <linux/config.h>
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#include <linux/kobject.h>
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#include <linux/string.h>
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#include <linux/sysfs.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#define KERNEL_ATTR_RO(_name) \
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static struct subsys_attribute _name##_attr = __ATTR_RO(_name)
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#define KERNEL_ATTR_RW(_name) \
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static struct subsys_attribute _name##_attr = \
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__ATTR(_name, 0644, _name##_show, _name##_store)
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#ifdef CONFIG_HOTPLUG
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/* current uevent sequence number */
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static ssize_t uevent_seqnum_show(struct subsystem *subsys, char *page)
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{
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return sprintf(page, "%llu\n", (unsigned long long)hotplug_seqnum);
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}
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KERNEL_ATTR_RO(uevent_seqnum);
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/* uevent helper program, used during early boo */
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static ssize_t uevent_helper_show(struct subsystem *subsys, char *page)
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{
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return sprintf(page, "%s\n", hotplug_path);
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}
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static ssize_t uevent_helper_store(struct subsystem *subsys, const char *page, size_t count)
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{
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if (count+1 > HOTPLUG_PATH_LEN)
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return -ENOENT;
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memcpy(hotplug_path, page, count);
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hotplug_path[count] = '\0';
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if (count && hotplug_path[count-1] == '\n')
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hotplug_path[count-1] = '\0';
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return count;
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}
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KERNEL_ATTR_RW(uevent_helper);
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#endif
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#ifdef CONFIG_KEXEC
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#include <asm/kexec.h>
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static ssize_t crash_notes_show(struct subsystem *subsys, char *page)
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{
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return sprintf(page, "%p\n", (void *)crash_notes);
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}
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KERNEL_ATTR_RO(crash_notes);
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#endif
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decl_subsys(kernel, NULL, NULL);
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EXPORT_SYMBOL_GPL(kernel_subsys);
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static struct attribute * kernel_attrs[] = {
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#ifdef CONFIG_HOTPLUG
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&uevent_seqnum_attr.attr,
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&uevent_helper_attr.attr,
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#endif
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#ifdef CONFIG_KEXEC
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&crash_notes_attr.attr,
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#endif
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NULL
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};
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static struct attribute_group kernel_attr_group = {
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.attrs = kernel_attrs,
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};
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static int __init ksysfs_init(void)
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{
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int error = subsystem_register(&kernel_subsys);
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if (!error)
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error = sysfs_create_group(&kernel_subsys.kset.kobj,
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&kernel_attr_group);
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return error;
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}
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core_initcall(ksysfs_init);
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