From 0f76e5acf9dc788e664056dda1e461f0bec93948 Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Fri, 11 Nov 2005 04:58:04 +0100 Subject: [PATCH] add uevent_helper control in /sys/kernel/ 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 Signed-off-by: Greg Kroah-Hartman --- kernel/ksysfs.c | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) (limited to 'kernel/ksysfs.c') diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c index 015fb69ad94d..e975a76a9d5b 100644 --- a/kernel/ksysfs.c +++ b/kernel/ksysfs.c @@ -23,11 +23,29 @@ static struct subsys_attribute _name##_attr = \ __ATTR(_name, 0644, _name##_show, _name##_store) #ifdef CONFIG_HOTPLUG -static ssize_t hotplug_seqnum_show(struct subsystem *subsys, char *page) +/* current uevent sequence number */ +static ssize_t uevent_seqnum_show(struct subsystem *subsys, char *page) { return sprintf(page, "%llu\n", (unsigned long long)hotplug_seqnum); } -KERNEL_ATTR_RO(hotplug_seqnum); +KERNEL_ATTR_RO(uevent_seqnum); + +/* uevent helper program, used during early boo */ +static ssize_t uevent_helper_show(struct subsystem *subsys, char *page) +{ + return sprintf(page, "%s\n", hotplug_path); +} +static ssize_t uevent_helper_store(struct subsystem *subsys, const char *page, size_t count) +{ + if (count+1 > HOTPLUG_PATH_LEN) + return -ENOENT; + memcpy(hotplug_path, page, count); + hotplug_path[count] = '\0'; + if (count && hotplug_path[count-1] == '\n') + hotplug_path[count-1] = '\0'; + return count; +} +KERNEL_ATTR_RW(uevent_helper); #endif #ifdef CONFIG_KEXEC @@ -45,7 +63,8 @@ EXPORT_SYMBOL_GPL(kernel_subsys); static struct attribute * kernel_attrs[] = { #ifdef CONFIG_HOTPLUG - &hotplug_seqnum_attr.attr, + &uevent_seqnum_attr.attr, + &uevent_helper_attr.attr, #endif #ifdef CONFIG_KEXEC &crash_notes_attr.attr, -- cgit v1.2.2