Merge branch 'linus' into percpu-cpumask-x86-for-linus-2

[safe/jmp/linux-2.6] / arch / x86 / kernel / cpuid.c

diff --git a/arch/x86/kernel/cpuid.c b/arch/x86/kernel/cpuid.c
index 288e7a6..2ac1f0c 100644 (file)
--- a/arch/x86/kernel/cpuid.c
+++ b/arch/x86/kernel/cpuid.c
@@ -33,16 +33,16 @@
 #include <linux/init.h>
 #include <linux/poll.h>
 #include <linux/smp.h>
+#include <linux/smp_lock.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 <asm/processor.h>
 #include <asm/msr.h>
-#include <asm/uaccess.h>
 #include <asm/system.h>
 
 static struct class *cpuid_class;
@@ -82,12 +82,14 @@ 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);
        u64 pos = *ppos;
+       ssize_t bytes = 0;
+       int err = 0;
 
        if (count % 16)
                return -EINVAL; /* Invalid chunk size */
@@ -95,27 +97,40 @@ 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;
+       int ret = 0;
 
-       if (cpu >= NR_CPUS || !cpu_online(cpu))
-               return -ENXIO;  /* No such CPU */
-       if (c->cpuid_level < 0)
-               return -EIO;    /* CPUID not supported */
+       lock_kernel();
 
-       return 0;
+       cpu = iminor(file->f_path.dentry->d_inode);
+       if (cpu >= nr_cpu_ids || !cpu_online(cpu)) {
+               ret = -ENXIO;   /* No such CPU */
+               goto out;
+       }
+       c = &cpu_data(cpu);
+       if (c->cpuid_level < 0)
+               ret = -EIO;     /* CPUID not supported */
+out:
+       unlock_kernel();
+       return ret;
 }
 
 /*
@@ -132,7 +147,7 @@ static __cpuinit 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;
 }
@@ -154,12 +169,10 @@ 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;
 }