1 files changed, 45 insertions, 26 deletions

diff --git a/arch/x86/kernel/cpuid.c b/arch/x86/kernel/cpuid.c
index 288e7a6598a..3225ae6c518 100644
--- a/arch/x86/kernel/cpuid.c
+++ b/arch/x86/kernel/cpuid.c
@@ -35,15 +35,14 @@
 #include <linux/smp.h>
 #include <linux/major.h>
 #include <linux/fs.h>
-#include <linux/smp_lock.h>
 #include <linux/device.h>
 #include <linux/cpu.h>
 #include <linux/notifier.h>
+#include <linux/uaccess.h>
+#include <linux/gfp.h>
 
 #include <asm/processor.h>
 #include <asm/msr.h>
-#include <asm/uaccess.h>
-#include <asm/system.h>
 
 static struct class *cpuid_class;
 
@@ -82,12 +81,14 @@ static loff_t cpuid_seek(struct file *file, loff_t offset, int orig)
 }
 
 static ssize_t cpuid_read(struct file *file, char __user *buf,
-			  size_t count, loff_t * ppos)
+			  size_t count, loff_t *ppos)
 {
 	char __user *tmp = buf;
 	struct cpuid_regs cmd;
-	int cpu = iminor(file->f_path.dentry->d_inode);
+	int cpu = iminor(file_inode(file));
 	u64 pos = *ppos;
+	ssize_t bytes = 0;
+	int err = 0;
 
 	if (count % 16)
 		return -EINVAL;	/* Invalid chunk size */
@@ -95,23 +96,31 @@ static ssize_t cpuid_read(struct file *file, char __user *buf,
 	for (; count; count -= 16) {
 		cmd.eax = pos;
 		cmd.ecx = pos >> 32;
-		smp_call_function_single(cpu, cpuid_smp_cpuid, &cmd, 1, 1);
-		if (copy_to_user(tmp, &cmd, 16))
-			return -EFAULT;
+		err = smp_call_function_single(cpu, cpuid_smp_cpuid, &cmd, 1);
+		if (err)
+			break;
+		if (copy_to_user(tmp, &cmd, 16)) {
+			err = -EFAULT;
+			break;
+		}
 		tmp += 16;
+		bytes += 16;
 		*ppos = ++pos;
 	}
 
-	return tmp - buf;
+	return bytes ? bytes : err;
 }
 
 static int cpuid_open(struct inode *inode, struct file *file)
 {
-	unsigned int cpu = iminor(file->f_path.dentry->d_inode);
-	struct cpuinfo_x86 *c = &cpu_data(cpu);
+	unsigned int cpu;
+	struct cpuinfo_x86 *c;
 
-	if (cpu >= NR_CPUS || !cpu_online(cpu))
+	cpu = iminor(file_inode(file));
+	if (cpu >= nr_cpu_ids || !cpu_online(cpu))
 		return -ENXIO;	/* No such CPU */
+
+	c = &cpu_data(cpu);
 	if (c->cpuid_level < 0)
 		return -EIO;	/* CPUID not supported */
 
@@ -128,11 +137,11 @@ static const struct file_operations cpuid_fops = {
 	.open = cpuid_open,
 };
 
-static __cpuinit int cpuid_device_create(int cpu)
+static int cpuid_device_create(int cpu)
 {
 	struct device *dev;
 
-	dev = device_create(cpuid_class, NULL, MKDEV(CPUID_MAJOR, cpu),
+	dev = device_create(cpuid_class, NULL, MKDEV(CPUID_MAJOR, cpu), NULL,
 			    "cpu%d", cpu);
 	return IS_ERR(dev) ? PTR_ERR(dev) : 0;
 }
@@ -142,9 +151,8 @@ static void cpuid_device_destroy(int cpu)
 	device_destroy(cpuid_class, MKDEV(CPUID_MAJOR, cpu));
 }
 
-static int __cpuinit cpuid_class_cpu_callback(struct notifier_block *nfb,
-					      unsigned long action,
-					      void *hcpu)
+static int cpuid_class_cpu_callback(struct notifier_block *nfb,
+				    unsigned long action, void *hcpu)
 {
 	unsigned int cpu = (unsigned long)hcpu;
 	int err = 0;
@@ -154,14 +162,12 @@ static int __cpuinit cpuid_class_cpu_callback(struct notifier_block *nfb,
 		err = cpuid_device_create(cpu);
 		break;
 	case CPU_UP_CANCELED:
+	case CPU_UP_CANCELED_FROZEN:
 	case CPU_DEAD:
 		cpuid_device_destroy(cpu);
 		break;
-	case CPU_UP_CANCELED_FROZEN:
-		destroy_suspended_device(cpuid_class, MKDEV(CPUID_MAJOR, cpu));
-		break;
 	}
-	return err ? NOTIFY_BAD : NOTIFY_OK;
+	return notifier_from_errno(err);
 }
 
 static struct notifier_block __refdata cpuid_class_cpu_notifier =
@@ -169,12 +175,18 @@ static struct notifier_block __refdata cpuid_class_cpu_notifier =
 	.notifier_call = cpuid_class_cpu_callback,
 };
 
+static char *cpuid_devnode(struct device *dev, umode_t *mode)
+{
+	return kasprintf(GFP_KERNEL, "cpu/%u/cpuid", MINOR(dev->devt));
+}
+
 static int __init cpuid_init(void)
 {
 	int i, err = 0;
 	i = 0;
 
-	if (register_chrdev(CPUID_MAJOR, "cpu/cpuid", &cpuid_fops)) {
+	if (__register_chrdev(CPUID_MAJOR, 0, NR_CPUS,
+			      "cpu/cpuid", &cpuid_fops)) {
 		printk(KERN_ERR "cpuid: unable to get major %d for cpuid\n",
 		       CPUID_MAJOR);
 		err = -EBUSY;
@@ -185,12 +197,16 @@ static int __init cpuid_init(void)
 		err = PTR_ERR(cpuid_class);
 		goto out_chrdev;
 	}
+	cpuid_class->devnode = cpuid_devnode;
+
+	cpu_notifier_register_begin();
 	for_each_online_cpu(i) {
 		err = cpuid_device_create(i);
 		if (err != 0)
 			goto out_class;
 	}
-	register_hotcpu_notifier(&cpuid_class_cpu_notifier);
+	__register_hotcpu_notifier(&cpuid_class_cpu_notifier);
+	cpu_notifier_register_done();
 
 	err = 0;
 	goto out;
@@ -200,9 +216,10 @@ out_class:
 	for_each_online_cpu(i) {
 		cpuid_device_destroy(i);
 	}
+	cpu_notifier_register_done();
 	class_destroy(cpuid_class);
 out_chrdev:
-	unregister_chrdev(CPUID_MAJOR, "cpu/cpuid");
+	__unregister_chrdev(CPUID_MAJOR, 0, NR_CPUS, "cpu/cpuid");
 out:
 	return err;
 }
@@ -211,11 +228,13 @@ static void __exit cpuid_exit(void)
 {
 	int cpu = 0;
 
+	cpu_notifier_register_begin();
 	for_each_online_cpu(cpu)
 		cpuid_device_destroy(cpu);
 	class_destroy(cpuid_class);
-	unregister_chrdev(CPUID_MAJOR, "cpu/cpuid");
-	unregister_hotcpu_notifier(&cpuid_class_cpu_notifier);
+	__unregister_chrdev(CPUID_MAJOR, 0, NR_CPUS, "cpu/cpuid");
+	__unregister_hotcpu_notifier(&cpuid_class_cpu_notifier);
+	cpu_notifier_register_done();
 }
 
 module_init(cpuid_init);