0b1937ac0e
Make it possible to use __start_notes and __stop_notes without getting a GPREL overflow error from the FRV linker. Small variables that would otherwise be in .data or .bss may, depending on the arch, be placed in special sections (.sdata or .sbss) that permit single instruction references on fixed instruction width machines. __start_notes and __stop_notes aren't really char variables, and certainly don't refer to data in .data or .bss. Making them type "void" fools the compiler into not assuming anything about them. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
123 lines
3 KiB
C
123 lines
3 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/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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#include <linux/kexec.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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#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
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/* current uevent sequence number */
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static ssize_t uevent_seqnum_show(struct kset *kset, char *page)
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{
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return sprintf(page, "%llu\n", (unsigned long long)uevent_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 kset *kset, char *page)
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{
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return sprintf(page, "%s\n", uevent_helper);
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}
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static ssize_t uevent_helper_store(struct kset *kset, const char *page, size_t count)
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{
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if (count+1 > UEVENT_HELPER_PATH_LEN)
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return -ENOENT;
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memcpy(uevent_helper, page, count);
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uevent_helper[count] = '\0';
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if (count && uevent_helper[count-1] == '\n')
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uevent_helper[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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static ssize_t kexec_loaded_show(struct kset *kset, char *page)
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{
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return sprintf(page, "%d\n", !!kexec_image);
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}
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KERNEL_ATTR_RO(kexec_loaded);
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static ssize_t kexec_crash_loaded_show(struct kset *kset, char *page)
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{
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return sprintf(page, "%d\n", !!kexec_crash_image);
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}
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KERNEL_ATTR_RO(kexec_crash_loaded);
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#endif /* CONFIG_KEXEC */
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/*
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* Make /sys/kernel/notes give the raw contents of our kernel .notes section.
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*/
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extern const void __start_notes __attribute__((weak));
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extern const void __stop_notes __attribute__((weak));
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#define notes_size (&__stop_notes - &__start_notes)
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static ssize_t notes_read(struct kobject *kobj, struct bin_attribute *bin_attr,
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char *buf, loff_t off, size_t count)
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{
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memcpy(buf, &__start_notes + off, count);
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return count;
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}
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static struct bin_attribute notes_attr = {
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.attr = {
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.name = "notes",
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.mode = S_IRUGO,
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},
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.read = ¬es_read,
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};
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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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#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
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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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&kexec_loaded_attr.attr,
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&kexec_crash_loaded_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.kobj,
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&kernel_attr_group);
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if (!error && notes_size > 0) {
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notes_attr.size = notes_size;
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error = sysfs_create_bin_file(&kernel_subsys.kobj,
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¬es_attr);
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}
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return error;
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}
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core_initcall(ksysfs_init);
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