diff options
Diffstat (limited to 'kernel/ksysfs.c')
| -rw-r--r-- | kernel/ksysfs.c | 30 |
1 files changed, 26 insertions, 4 deletions
diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c index 015fb69ad94..99af8b05eea 100644 --- a/kernel/ksysfs.c +++ b/kernel/ksysfs.c @@ -15,6 +15,9 @@ #include <linux/module.h> #include <linux/init.h> +u64 uevent_seqnum; +char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug"; + #define KERNEL_ATTR_RO(_name) \ static struct subsys_attribute _name##_attr = __ATTR_RO(_name) @@ -23,11 +26,29 @@ 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)uevent_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", uevent_helper); +} +static ssize_t uevent_helper_store(struct subsystem *subsys, const char *page, size_t count) { - return sprintf(page, "%llu\n", (unsigned long long)hotplug_seqnum); + 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_RO(hotplug_seqnum); +KERNEL_ATTR_RW(uevent_helper); #endif #ifdef CONFIG_KEXEC @@ -45,7 +66,8 @@ 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, |