*
* ----------------------------------------------------------------------- */
-
/*
* cpuid.c
*
#include <linux/fs.h>
#include <linux/smp_lock.h>
#include <linux/fs.h>
+#include <linux/device.h>
+#include <linux/cpu.h>
+#include <linux/notifier.h>
#include <asm/processor.h>
#include <asm/msr.h>
#include <asm/uaccess.h>
#include <asm/system.h>
+static struct class *cpuid_class;
+
#ifdef CONFIG_SMP
struct cpuid_command {
- int cpu;
- u32 reg;
- u32 *data;
+ int cpu;
+ u32 reg;
+ u32 *data;
};
static void cpuid_smp_cpuid(void *cmd_block)
{
- struct cpuid_command *cmd = (struct cpuid_command *) cmd_block;
-
- if ( cmd->cpu == smp_processor_id() )
- cpuid(cmd->reg, &cmd->data[0], &cmd->data[1], &cmd->data[2], &cmd->data[3]);
+ struct cpuid_command *cmd = (struct cpuid_command *)cmd_block;
+
+ if (cmd->cpu == smp_processor_id())
+ cpuid(cmd->reg, &cmd->data[0], &cmd->data[1], &cmd->data[2],
+ &cmd->data[3]);
}
-static inline void do_cpuid(int cpu, u32 reg, u32 *data)
+static inline void do_cpuid(int cpu, u32 reg, u32 * data)
{
- struct cpuid_command cmd;
-
- preempt_disable();
- if ( cpu == smp_processor_id() ) {
- cpuid(reg, &data[0], &data[1], &data[2], &data[3]);
- } else {
- cmd.cpu = cpu;
- cmd.reg = reg;
- cmd.data = data;
-
- smp_call_function(cpuid_smp_cpuid, &cmd, 1, 1);
- }
- preempt_enable();
+ struct cpuid_command cmd;
+
+ preempt_disable();
+ if (cpu == smp_processor_id()) {
+ cpuid(reg, &data[0], &data[1], &data[2], &data[3]);
+ } else {
+ cmd.cpu = cpu;
+ cmd.reg = reg;
+ cmd.data = data;
+
+ smp_call_function(cpuid_smp_cpuid, &cmd, 1, 1);
+ }
+ preempt_enable();
}
-#else /* ! CONFIG_SMP */
+#else /* ! CONFIG_SMP */
-static inline void do_cpuid(int cpu, u32 reg, u32 *data)
+static inline void do_cpuid(int cpu, u32 reg, u32 * data)
{
- cpuid(reg, &data[0], &data[1], &data[2], &data[3]);
+ cpuid(reg, &data[0], &data[1], &data[2], &data[3]);
}
-#endif /* ! CONFIG_SMP */
+#endif /* ! CONFIG_SMP */
static loff_t cpuid_seek(struct file *file, loff_t offset, int orig)
{
- loff_t ret;
-
- lock_kernel();
-
- switch (orig) {
- case 0:
- file->f_pos = offset;
- ret = file->f_pos;
- break;
- case 1:
- file->f_pos += offset;
- ret = file->f_pos;
- break;
- default:
- ret = -EINVAL;
- }
-
- unlock_kernel();
- return ret;
+ loff_t ret;
+
+ lock_kernel();
+
+ switch (orig) {
+ case 0:
+ file->f_pos = offset;
+ ret = file->f_pos;
+ break;
+ case 1:
+ file->f_pos += offset;
+ ret = file->f_pos;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ unlock_kernel();
+ return ret;
}
-static ssize_t cpuid_read(struct file * file, char * buf,
- size_t count, loff_t *ppos)
+static ssize_t cpuid_read(struct file *file, char __user *buf,
+ size_t count, loff_t * ppos)
{
- u32 *tmp = (u32 *)buf;
- u32 data[4];
- size_t rv;
- u32 reg = *ppos;
- int cpu = iminor(file->f_dentry->d_inode);
-
- if ( count % 16 )
- return -EINVAL; /* Invalid chunk size */
-
- for ( rv = 0 ; count ; count -= 16 ) {
- do_cpuid(cpu, reg, data);
- if ( copy_to_user(tmp,&data,16) )
- return -EFAULT;
- tmp += 4;
- *ppos = reg++;
- }
-
- return ((char *)tmp) - buf;
+ char __user *tmp = buf;
+ u32 data[4];
+ u32 reg = *ppos;
+ int cpu = iminor(file->f_dentry->d_inode);
+
+ if (count % 16)
+ return -EINVAL; /* Invalid chunk size */
+
+ for (; count; count -= 16) {
+ do_cpuid(cpu, reg, data);
+ if (copy_to_user(tmp, &data, 16))
+ return -EFAULT;
+ tmp += 16;
+ *ppos = reg++;
+ }
+
+ return tmp - buf;
}
static int cpuid_open(struct inode *inode, struct file *file)
{
- int cpu = iminor(file->f_dentry->d_inode);
- struct cpuinfo_x86 *c = &(cpu_data)[cpu];
-
- if (!cpu_online(cpu))
- return -ENXIO; /* No such CPU */
- if ( c->cpuid_level < 0 )
- return -EIO; /* CPUID not supported */
-
- return 0;
+ unsigned int cpu = iminor(file->f_dentry->d_inode);
+ struct cpuinfo_x86 *c = &(cpu_data)[cpu];
+
+ if (cpu >= NR_CPUS || !cpu_online(cpu))
+ return -ENXIO; /* No such CPU */
+ if (c->cpuid_level < 0)
+ return -EIO; /* CPUID not supported */
+
+ return 0;
}
/*
* File operations we support
*/
static struct file_operations cpuid_fops = {
- .owner = THIS_MODULE,
- .llseek = cpuid_seek,
- .read = cpuid_read,
- .open = cpuid_open,
+ .owner = THIS_MODULE,
+ .llseek = cpuid_seek,
+ .read = cpuid_read,
+ .open = cpuid_open,
};
-int __init cpuid_init(void)
+static int cpuid_class_device_create(int i)
{
- if (register_chrdev(CPUID_MAJOR, "cpu/cpuid", &cpuid_fops)) {
- printk(KERN_ERR "cpuid: unable to get major %d for cpuid\n",
- CPUID_MAJOR);
- return -EBUSY;
- }
+ int err = 0;
+ struct class_device *class_err;
+
+ class_err = class_device_create(cpuid_class, NULL, MKDEV(CPUID_MAJOR, i), NULL, "cpu%d",i);
+ if (IS_ERR(class_err))
+ err = PTR_ERR(class_err);
+ return err;
+}
- return 0;
+static int __devinit cpuid_class_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned long)hcpu;
+
+ switch (action) {
+ case CPU_ONLINE:
+ cpuid_class_device_create(cpu);
+ break;
+ case CPU_DEAD:
+ class_device_destroy(cpuid_class, MKDEV(CPUID_MAJOR, cpu));
+ break;
+ }
+ return NOTIFY_OK;
}
-void __exit cpuid_exit(void)
+static struct notifier_block cpuid_class_cpu_notifier =
{
- unregister_chrdev(CPUID_MAJOR, "cpu/cpuid");
+ .notifier_call = cpuid_class_cpu_callback,
+};
+
+static int __init cpuid_init(void)
+{
+ int i, err = 0;
+ i = 0;
+
+ if (register_chrdev(CPUID_MAJOR, "cpu/cpuid", &cpuid_fops)) {
+ printk(KERN_ERR "cpuid: unable to get major %d for cpuid\n",
+ CPUID_MAJOR);
+ err = -EBUSY;
+ goto out;
+ }
+ cpuid_class = class_create(THIS_MODULE, "cpuid");
+ if (IS_ERR(cpuid_class)) {
+ err = PTR_ERR(cpuid_class);
+ goto out_chrdev;
+ }
+ for_each_online_cpu(i) {
+ err = cpuid_class_device_create(i);
+ if (err != 0)
+ goto out_class;
+ }
+ register_cpu_notifier(&cpuid_class_cpu_notifier);
+
+ err = 0;
+ goto out;
+
+out_class:
+ i = 0;
+ for_each_online_cpu(i) {
+ class_device_destroy(cpuid_class, MKDEV(CPUID_MAJOR, i));
+ }
+ class_destroy(cpuid_class);
+out_chrdev:
+ unregister_chrdev(CPUID_MAJOR, "cpu/cpuid");
+out:
+ return err;
+}
+
+static void __exit cpuid_exit(void)
+{
+ int cpu = 0;
+
+ for_each_online_cpu(cpu)
+ class_device_destroy(cpuid_class, MKDEV(CPUID_MAJOR, cpu));
+ class_destroy(cpuid_class);
+ unregister_chrdev(CPUID_MAJOR, "cpu/cpuid");
+ unregister_cpu_notifier(&cpuid_class_cpu_notifier);
}
module_init(cpuid_init);
-module_exit(cpuid_exit)
+module_exit(cpuid_exit);
MODULE_AUTHOR("H. Peter Anvin <hpa@zytor.com>");
MODULE_DESCRIPTION("x86 generic CPUID driver");