diff options
Diffstat (limited to 'kernel/ksysfs.c')
-rw-r--r-- | kernel/ksysfs.c | 114 |
1 files changed, 79 insertions, 35 deletions
diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c index 35859da8bd4f..eefb67d9883c 100644 --- a/kernel/ksysfs.c +++ b/kernel/ksysfs.c @@ -6,6 +6,7 @@ * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org> */ +#include <asm/byteorder.h> #include <linux/kobject.h> #include <linux/string.h> #include <linux/sysfs.h> @@ -20,27 +21,50 @@ #include <linux/rcupdate.h> /* rcu_expedited and rcu_normal */ +#if defined(__LITTLE_ENDIAN) +#define CPU_BYTEORDER_STRING "little" +#elif defined(__BIG_ENDIAN) +#define CPU_BYTEORDER_STRING "big" +#else +#error Unknown byteorder +#endif + #define KERNEL_ATTR_RO(_name) \ static struct kobj_attribute _name##_attr = __ATTR_RO(_name) #define KERNEL_ATTR_RW(_name) \ -static struct kobj_attribute _name##_attr = \ - __ATTR(_name, 0644, _name##_show, _name##_store) +static struct kobj_attribute _name##_attr = __ATTR_RW(_name) /* current uevent sequence number */ static ssize_t uevent_seqnum_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%llu\n", (unsigned long long)uevent_seqnum); + return sysfs_emit(buf, "%llu\n", (u64)atomic64_read(&uevent_seqnum)); } KERNEL_ATTR_RO(uevent_seqnum); +/* cpu byteorder */ +static ssize_t cpu_byteorder_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sysfs_emit(buf, "%s\n", CPU_BYTEORDER_STRING); +} +KERNEL_ATTR_RO(cpu_byteorder); + +/* address bits */ +static ssize_t address_bits_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sysfs_emit(buf, "%zu\n", sizeof(void *) * 8 /* CHAR_BIT */); +} +KERNEL_ATTR_RO(address_bits); + #ifdef CONFIG_UEVENT_HELPER /* uevent helper program, used during early boot */ static ssize_t uevent_helper_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%s\n", uevent_helper); + return sysfs_emit(buf, "%s\n", uevent_helper); } static ssize_t uevent_helper_store(struct kobject *kobj, struct kobj_attribute *attr, @@ -61,14 +85,21 @@ KERNEL_ATTR_RW(uevent_helper); static ssize_t profiling_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", prof_on); + return sysfs_emit(buf, "%d\n", prof_on); } static ssize_t profiling_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { int ret; + static DEFINE_MUTEX(lock); + /* + * We need serialization, for profile_setup() initializes prof_on + * value and profile_init() must not reallocate prof_buffer after + * once allocated. + */ + guard(mutex)(&lock); if (prof_on) return -EEXIST; /* @@ -92,21 +123,27 @@ KERNEL_ATTR_RW(profiling); static ssize_t kexec_loaded_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", !!kexec_image); + return sysfs_emit(buf, "%d\n", !!kexec_image); } KERNEL_ATTR_RO(kexec_loaded); +#ifdef CONFIG_CRASH_DUMP static ssize_t kexec_crash_loaded_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", kexec_crash_loaded()); + return sysfs_emit(buf, "%d\n", kexec_crash_loaded()); } KERNEL_ATTR_RO(kexec_crash_loaded); static ssize_t kexec_crash_size_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%zu\n", crash_get_memory_size()); + ssize_t size = crash_get_memory_size(); + + if (size < 0) + return size; + + return sysfs_emit(buf, "%zd\n", size); } static ssize_t kexec_crash_size_store(struct kobject *kobj, struct kobj_attribute *attr, @@ -123,26 +160,39 @@ static ssize_t kexec_crash_size_store(struct kobject *kobj, } KERNEL_ATTR_RW(kexec_crash_size); +#endif /* CONFIG_CRASH_DUMP*/ #endif /* CONFIG_KEXEC_CORE */ -#ifdef CONFIG_CRASH_CORE +#ifdef CONFIG_VMCORE_INFO static ssize_t vmcoreinfo_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { phys_addr_t vmcore_base = paddr_vmcoreinfo_note(); - return sprintf(buf, "%pa %x\n", &vmcore_base, - (unsigned int)VMCOREINFO_NOTE_SIZE); + return sysfs_emit(buf, "%pa %x\n", &vmcore_base, + (unsigned int)VMCOREINFO_NOTE_SIZE); } KERNEL_ATTR_RO(vmcoreinfo); -#endif /* CONFIG_CRASH_CORE */ +#ifdef CONFIG_CRASH_HOTPLUG +static ssize_t crash_elfcorehdr_size_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + unsigned int sz = crash_get_elfcorehdr_size(); + + return sysfs_emit(buf, "%u\n", sz); +} +KERNEL_ATTR_RO(crash_elfcorehdr_size); + +#endif + +#endif /* CONFIG_VMCORE_INFO */ /* whether file capabilities are enabled */ static ssize_t fscaps_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", file_caps_enabled); + return sysfs_emit(buf, "%d\n", file_caps_enabled); } KERNEL_ATTR_RO(fscaps); @@ -151,7 +201,7 @@ int rcu_expedited; static ssize_t rcu_expedited_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", READ_ONCE(rcu_expedited)); + return sysfs_emit(buf, "%d\n", READ_ONCE(rcu_expedited)); } static ssize_t rcu_expedited_store(struct kobject *kobj, struct kobj_attribute *attr, @@ -168,7 +218,7 @@ int rcu_normal; static ssize_t rcu_normal_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", READ_ONCE(rcu_normal)); + return sysfs_emit(buf, "%d\n", READ_ONCE(rcu_normal)); } static ssize_t rcu_normal_store(struct kobject *kobj, struct kobj_attribute *attr, @@ -185,25 +235,11 @@ KERNEL_ATTR_RW(rcu_normal); /* * Make /sys/kernel/notes give the raw contents of our kernel .notes section. */ -extern const void __start_notes __weak; -extern const void __stop_notes __weak; +extern const void __start_notes; +extern const void __stop_notes; #define notes_size (&__stop_notes - &__start_notes) -static ssize_t notes_read(struct file *filp, 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 __ro_after_init = { - .attr = { - .name = "notes", - .mode = S_IRUGO, - }, - .read = ¬es_read, -}; +static __ro_after_init BIN_ATTR_SIMPLE_RO(notes); struct kobject *kernel_kobj; EXPORT_SYMBOL_GPL(kernel_kobj); @@ -211,6 +247,8 @@ EXPORT_SYMBOL_GPL(kernel_kobj); static struct attribute * kernel_attrs[] = { &fscaps_attr.attr, &uevent_seqnum_attr.attr, + &cpu_byteorder_attr.attr, + &address_bits_attr.attr, #ifdef CONFIG_UEVENT_HELPER &uevent_helper_attr.attr, #endif @@ -219,11 +257,16 @@ static struct attribute * kernel_attrs[] = { #endif #ifdef CONFIG_KEXEC_CORE &kexec_loaded_attr.attr, +#ifdef CONFIG_CRASH_DUMP &kexec_crash_loaded_attr.attr, &kexec_crash_size_attr.attr, #endif -#ifdef CONFIG_CRASH_CORE +#endif +#ifdef CONFIG_VMCORE_INFO &vmcoreinfo_attr.attr, +#ifdef CONFIG_CRASH_HOTPLUG + &crash_elfcorehdr_size_attr.attr, +#endif #endif #ifndef CONFIG_TINY_RCU &rcu_expedited_attr.attr, @@ -250,8 +293,9 @@ static int __init ksysfs_init(void) goto kset_exit; if (notes_size > 0) { - notes_attr.size = notes_size; - error = sysfs_create_bin_file(kernel_kobj, ¬es_attr); + bin_attr_notes.private = (void *)&__start_notes; + bin_attr_notes.size = notes_size; + error = sysfs_create_bin_file(kernel_kobj, &bin_attr_notes); if (error) goto group_exit; } |