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Diffstat (limited to 'arch/x86/kernel/msr.c')
-rw-r--r--arch/x86/kernel/msr.c61
1 files changed, 53 insertions, 8 deletions
diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c
index 98fd6cd4e3a..7dd95009417 100644
--- a/arch/x86/kernel/msr.c
+++ b/arch/x86/kernel/msr.c
@@ -1,6 +1,7 @@
/* ----------------------------------------------------------------------- *
*
* Copyright 2000-2008 H. Peter Anvin - All Rights Reserved
+ * Copyright 2009 Intel Corporation; author: H. Peter Anvin
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -80,11 +81,8 @@ static ssize_t msr_read(struct file *file, char __user *buf,
for (; count; count -= 8) {
err = rdmsr_safe_on_cpu(cpu, reg, &data[0], &data[1]);
- if (err) {
- if (err == -EFAULT) /* Fix idiotic error code */
- err = -EIO;
+ if (err)
break;
- }
if (copy_to_user(tmp, &data, 8)) {
err = -EFAULT;
break;
@@ -115,11 +113,8 @@ static ssize_t msr_write(struct file *file, const char __user *buf,
break;
}
err = wrmsr_safe_on_cpu(cpu, reg, data[0], data[1]);
- if (err) {
- if (err == -EFAULT) /* Fix idiotic error code */
- err = -EIO;
+ if (err)
break;
- }
tmp += 2;
bytes += 8;
}
@@ -127,6 +122,54 @@ static ssize_t msr_write(struct file *file, const char __user *buf,
return bytes ? bytes : err;
}
+static long msr_ioctl(struct file *file, unsigned int ioc, unsigned long arg)
+{
+ u32 __user *uregs = (u32 __user *)arg;
+ u32 regs[8];
+ int cpu = iminor(file->f_path.dentry->d_inode);
+ int err;
+
+ switch (ioc) {
+ case X86_IOC_RDMSR_REGS:
+ if (!(file->f_mode & FMODE_READ)) {
+ err = -EBADF;
+ break;
+ }
+ if (copy_from_user(&regs, uregs, sizeof regs)) {
+ err = -EFAULT;
+ break;
+ }
+ err = rdmsr_safe_regs_on_cpu(cpu, regs);
+ if (err)
+ break;
+ if (copy_to_user(uregs, &regs, sizeof regs))
+ err = -EFAULT;
+ break;
+
+ case X86_IOC_WRMSR_REGS:
+ if (!(file->f_mode & FMODE_WRITE)) {
+ err = -EBADF;
+ break;
+ }
+ if (copy_from_user(&regs, uregs, sizeof regs)) {
+ err = -EFAULT;
+ break;
+ }
+ err = wrmsr_safe_regs_on_cpu(cpu, regs);
+ if (err)
+ break;
+ if (copy_to_user(uregs, &regs, sizeof regs))
+ err = -EFAULT;
+ break;
+
+ default:
+ err = -ENOTTY;
+ break;
+ }
+
+ return err;
+}
+
static int msr_open(struct inode *inode, struct file *file)
{
unsigned int cpu = iminor(file->f_path.dentry->d_inode);
@@ -157,6 +200,8 @@ static const struct file_operations msr_fops = {
.read = msr_read,
.write = msr_write,
.open = msr_open,
+ .unlocked_ioctl = msr_ioctl,
+ .compat_ioctl = msr_ioctl,
};
static int __cpuinit msr_device_create(int cpu)