[PATCH 1/4] MSR: Prep for separating msr.c into three files
From: Marty McFadden
Date: Thu Feb 25 2016 - 19:13:21 EST
DEPENDENCY: Compilation depends upon next commit. This commit only
does the rename of msr.c --> msr_entry.c.
Separated in to two commits so that "git am" would work
without complaint.
No functional change (yet). Just preparation for splitting the
MSR kernel module into three separate implementation files:
1) msr_entry.c - Original msr driver and entry (now)
2) msr_whitelist.c - MSR Whitelist implementation (patch 2)
3) msr_batch.c - MSR Batch implementation (patch 3)
Signed-off-by: Marty McFadden <mcfadden8@xxxxxxxx>
---
arch/x86/kernel/msr.c | 284 -------------------------------------------
arch/x86/kernel/msr_entry.c | 284 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 284 insertions(+), 284 deletions(-)
delete mode 100644 arch/x86/kernel/msr.c
create mode 100644 arch/x86/kernel/msr_entry.c
diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c
deleted file mode 100644
index 64f9616..0000000
--- a/arch/x86/kernel/msr.c
+++ /dev/null
@@ -1,284 +0,0 @@
-/* ----------------------------------------------------------------------- *
- *
- * 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
- * the Free Software Foundation, Inc., 675 Mass Ave, Cambridge MA 02139,
- * USA; either version 2 of the License, or (at your option) any later
- * version; incorporated herein by reference.
- *
- * ----------------------------------------------------------------------- */
-
-/*
- * x86 MSR access device
- *
- * This device is accessed by lseek() to the appropriate register number
- * and then read/write in chunks of 8 bytes. A larger size means multiple
- * reads or writes of the same register.
- *
- * This driver uses /dev/cpu/%d/msr where %d is the minor number, and on
- * an SMP box will direct the access to CPU %d.
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/module.h>
-
-#include <linux/types.h>
-#include <linux/errno.h>
-#include <linux/fcntl.h>
-#include <linux/init.h>
-#include <linux/poll.h>
-#include <linux/smp.h>
-#include <linux/major.h>
-#include <linux/fs.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>
-
-static struct class *msr_class;
-
-static ssize_t msr_read(struct file *file, char __user *buf,
- size_t count, loff_t *ppos)
-{
- u32 __user *tmp = (u32 __user *) buf;
- u32 data[2];
- u32 reg = *ppos;
- int cpu = iminor(file_inode(file));
- int err = 0;
- ssize_t bytes = 0;
-
- if (count % 8)
- return -EINVAL; /* Invalid chunk size */
-
- for (; count; count -= 8) {
- err = rdmsr_safe_on_cpu(cpu, reg, &data[0], &data[1]);
- if (err)
- break;
- if (copy_to_user(tmp, &data, 8)) {
- err = -EFAULT;
- break;
- }
- tmp += 2;
- bytes += 8;
- }
-
- return bytes ? bytes : err;
-}
-
-static ssize_t msr_write(struct file *file, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- const u32 __user *tmp = (const u32 __user *)buf;
- u32 data[2];
- u32 reg = *ppos;
- int cpu = iminor(file_inode(file));
- int err = 0;
- ssize_t bytes = 0;
-
- if (count % 8)
- return -EINVAL; /* Invalid chunk size */
-
- for (; count; count -= 8) {
- if (copy_from_user(&data, tmp, 8)) {
- err = -EFAULT;
- break;
- }
- err = wrmsr_safe_on_cpu(cpu, reg, data[0], data[1]);
- if (err)
- break;
- tmp += 2;
- bytes += 8;
- }
-
- 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_inode(file));
- int err;
-
- switch (ioc) {
- case X86_IOC_RDMSR_REGS:
- if (!(file->f_mode & FMODE_READ)) {
- err = -EBADF;
- break;
- }
- if (copy_from_user(®s, uregs, sizeof regs)) {
- err = -EFAULT;
- break;
- }
- err = rdmsr_safe_regs_on_cpu(cpu, regs);
- if (err)
- break;
- if (copy_to_user(uregs, ®s, sizeof regs))
- err = -EFAULT;
- break;
-
- case X86_IOC_WRMSR_REGS:
- if (!(file->f_mode & FMODE_WRITE)) {
- err = -EBADF;
- break;
- }
- if (copy_from_user(®s, uregs, sizeof regs)) {
- err = -EFAULT;
- break;
- }
- err = wrmsr_safe_regs_on_cpu(cpu, regs);
- if (err)
- break;
- if (copy_to_user(uregs, ®s, 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_inode(file));
- struct cpuinfo_x86 *c;
-
- if (!capable(CAP_SYS_RAWIO))
- return -EPERM;
-
- if (cpu >= nr_cpu_ids || !cpu_online(cpu))
- return -ENXIO; /* No such CPU */
-
- c = &cpu_data(cpu);
- if (!cpu_has(c, X86_FEATURE_MSR))
- return -EIO; /* MSR not supported */
-
- return 0;
-}
-
-/*
- * File operations we support
- */
-static const struct file_operations msr_fops = {
- .owner = THIS_MODULE,
- .llseek = no_seek_end_llseek,
- .read = msr_read,
- .write = msr_write,
- .open = msr_open,
- .unlocked_ioctl = msr_ioctl,
- .compat_ioctl = msr_ioctl,
-};
-
-static int msr_device_create(int cpu)
-{
- struct device *dev;
-
- dev = device_create(msr_class, NULL, MKDEV(MSR_MAJOR, cpu), NULL,
- "msr%d", cpu);
- return PTR_ERR_OR_ZERO(dev);
-}
-
-static void msr_device_destroy(int cpu)
-{
- device_destroy(msr_class, MKDEV(MSR_MAJOR, cpu));
-}
-
-static int msr_class_cpu_callback(struct notifier_block *nfb,
- unsigned long action, void *hcpu)
-{
- unsigned int cpu = (unsigned long)hcpu;
- int err = 0;
-
- switch (action) {
- case CPU_UP_PREPARE:
- err = msr_device_create(cpu);
- break;
- case CPU_UP_CANCELED:
- case CPU_UP_CANCELED_FROZEN:
- case CPU_DEAD:
- msr_device_destroy(cpu);
- break;
- }
- return notifier_from_errno(err);
-}
-
-static struct notifier_block __refdata msr_class_cpu_notifier = {
- .notifier_call = msr_class_cpu_callback,
-};
-
-static char *msr_devnode(struct device *dev, umode_t *mode)
-{
- return kasprintf(GFP_KERNEL, "cpu/%u/msr", MINOR(dev->devt));
-}
-
-static int __init msr_init(void)
-{
- int i, err = 0;
- i = 0;
-
- if (__register_chrdev(MSR_MAJOR, 0, NR_CPUS, "cpu/msr", &msr_fops)) {
- pr_err("unable to get major %d for msr\n", MSR_MAJOR);
- err = -EBUSY;
- goto out;
- }
- msr_class = class_create(THIS_MODULE, "msr");
- if (IS_ERR(msr_class)) {
- err = PTR_ERR(msr_class);
- goto out_chrdev;
- }
- msr_class->devnode = msr_devnode;
-
- cpu_notifier_register_begin();
- for_each_online_cpu(i) {
- err = msr_device_create(i);
- if (err != 0)
- goto out_class;
- }
- __register_hotcpu_notifier(&msr_class_cpu_notifier);
- cpu_notifier_register_done();
-
- err = 0;
- goto out;
-
-out_class:
- i = 0;
- for_each_online_cpu(i)
- msr_device_destroy(i);
- cpu_notifier_register_done();
- class_destroy(msr_class);
-out_chrdev:
- __unregister_chrdev(MSR_MAJOR, 0, NR_CPUS, "cpu/msr");
-out:
- return err;
-}
-
-static void __exit msr_exit(void)
-{
- int cpu = 0;
-
- cpu_notifier_register_begin();
- for_each_online_cpu(cpu)
- msr_device_destroy(cpu);
- class_destroy(msr_class);
- __unregister_chrdev(MSR_MAJOR, 0, NR_CPUS, "cpu/msr");
- __unregister_hotcpu_notifier(&msr_class_cpu_notifier);
- cpu_notifier_register_done();
-}
-
-module_init(msr_init);
-module_exit(msr_exit)
-
-MODULE_AUTHOR("H. Peter Anvin <hpa@xxxxxxxxx>");
-MODULE_DESCRIPTION("x86 generic MSR driver");
-MODULE_LICENSE("GPL");
diff --git a/arch/x86/kernel/msr_entry.c b/arch/x86/kernel/msr_entry.c
new file mode 100644
index 0000000..64f9616
--- /dev/null
+++ b/arch/x86/kernel/msr_entry.c
@@ -0,0 +1,284 @@
+/* ----------------------------------------------------------------------- *
+ *
+ * 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
+ * the Free Software Foundation, Inc., 675 Mass Ave, Cambridge MA 02139,
+ * USA; either version 2 of the License, or (at your option) any later
+ * version; incorporated herein by reference.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * x86 MSR access device
+ *
+ * This device is accessed by lseek() to the appropriate register number
+ * and then read/write in chunks of 8 bytes. A larger size means multiple
+ * reads or writes of the same register.
+ *
+ * This driver uses /dev/cpu/%d/msr where %d is the minor number, and on
+ * an SMP box will direct the access to CPU %d.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/fcntl.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/smp.h>
+#include <linux/major.h>
+#include <linux/fs.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>
+
+static struct class *msr_class;
+
+static ssize_t msr_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ u32 __user *tmp = (u32 __user *) buf;
+ u32 data[2];
+ u32 reg = *ppos;
+ int cpu = iminor(file_inode(file));
+ int err = 0;
+ ssize_t bytes = 0;
+
+ if (count % 8)
+ return -EINVAL; /* Invalid chunk size */
+
+ for (; count; count -= 8) {
+ err = rdmsr_safe_on_cpu(cpu, reg, &data[0], &data[1]);
+ if (err)
+ break;
+ if (copy_to_user(tmp, &data, 8)) {
+ err = -EFAULT;
+ break;
+ }
+ tmp += 2;
+ bytes += 8;
+ }
+
+ return bytes ? bytes : err;
+}
+
+static ssize_t msr_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ const u32 __user *tmp = (const u32 __user *)buf;
+ u32 data[2];
+ u32 reg = *ppos;
+ int cpu = iminor(file_inode(file));
+ int err = 0;
+ ssize_t bytes = 0;
+
+ if (count % 8)
+ return -EINVAL; /* Invalid chunk size */
+
+ for (; count; count -= 8) {
+ if (copy_from_user(&data, tmp, 8)) {
+ err = -EFAULT;
+ break;
+ }
+ err = wrmsr_safe_on_cpu(cpu, reg, data[0], data[1]);
+ if (err)
+ break;
+ tmp += 2;
+ bytes += 8;
+ }
+
+ 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_inode(file));
+ int err;
+
+ switch (ioc) {
+ case X86_IOC_RDMSR_REGS:
+ if (!(file->f_mode & FMODE_READ)) {
+ err = -EBADF;
+ break;
+ }
+ if (copy_from_user(®s, uregs, sizeof regs)) {
+ err = -EFAULT;
+ break;
+ }
+ err = rdmsr_safe_regs_on_cpu(cpu, regs);
+ if (err)
+ break;
+ if (copy_to_user(uregs, ®s, sizeof regs))
+ err = -EFAULT;
+ break;
+
+ case X86_IOC_WRMSR_REGS:
+ if (!(file->f_mode & FMODE_WRITE)) {
+ err = -EBADF;
+ break;
+ }
+ if (copy_from_user(®s, uregs, sizeof regs)) {
+ err = -EFAULT;
+ break;
+ }
+ err = wrmsr_safe_regs_on_cpu(cpu, regs);
+ if (err)
+ break;
+ if (copy_to_user(uregs, ®s, 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_inode(file));
+ struct cpuinfo_x86 *c;
+
+ if (!capable(CAP_SYS_RAWIO))
+ return -EPERM;
+
+ if (cpu >= nr_cpu_ids || !cpu_online(cpu))
+ return -ENXIO; /* No such CPU */
+
+ c = &cpu_data(cpu);
+ if (!cpu_has(c, X86_FEATURE_MSR))
+ return -EIO; /* MSR not supported */
+
+ return 0;
+}
+
+/*
+ * File operations we support
+ */
+static const struct file_operations msr_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_seek_end_llseek,
+ .read = msr_read,
+ .write = msr_write,
+ .open = msr_open,
+ .unlocked_ioctl = msr_ioctl,
+ .compat_ioctl = msr_ioctl,
+};
+
+static int msr_device_create(int cpu)
+{
+ struct device *dev;
+
+ dev = device_create(msr_class, NULL, MKDEV(MSR_MAJOR, cpu), NULL,
+ "msr%d", cpu);
+ return PTR_ERR_OR_ZERO(dev);
+}
+
+static void msr_device_destroy(int cpu)
+{
+ device_destroy(msr_class, MKDEV(MSR_MAJOR, cpu));
+}
+
+static int msr_class_cpu_callback(struct notifier_block *nfb,
+ unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned long)hcpu;
+ int err = 0;
+
+ switch (action) {
+ case CPU_UP_PREPARE:
+ err = msr_device_create(cpu);
+ break;
+ case CPU_UP_CANCELED:
+ case CPU_UP_CANCELED_FROZEN:
+ case CPU_DEAD:
+ msr_device_destroy(cpu);
+ break;
+ }
+ return notifier_from_errno(err);
+}
+
+static struct notifier_block __refdata msr_class_cpu_notifier = {
+ .notifier_call = msr_class_cpu_callback,
+};
+
+static char *msr_devnode(struct device *dev, umode_t *mode)
+{
+ return kasprintf(GFP_KERNEL, "cpu/%u/msr", MINOR(dev->devt));
+}
+
+static int __init msr_init(void)
+{
+ int i, err = 0;
+ i = 0;
+
+ if (__register_chrdev(MSR_MAJOR, 0, NR_CPUS, "cpu/msr", &msr_fops)) {
+ pr_err("unable to get major %d for msr\n", MSR_MAJOR);
+ err = -EBUSY;
+ goto out;
+ }
+ msr_class = class_create(THIS_MODULE, "msr");
+ if (IS_ERR(msr_class)) {
+ err = PTR_ERR(msr_class);
+ goto out_chrdev;
+ }
+ msr_class->devnode = msr_devnode;
+
+ cpu_notifier_register_begin();
+ for_each_online_cpu(i) {
+ err = msr_device_create(i);
+ if (err != 0)
+ goto out_class;
+ }
+ __register_hotcpu_notifier(&msr_class_cpu_notifier);
+ cpu_notifier_register_done();
+
+ err = 0;
+ goto out;
+
+out_class:
+ i = 0;
+ for_each_online_cpu(i)
+ msr_device_destroy(i);
+ cpu_notifier_register_done();
+ class_destroy(msr_class);
+out_chrdev:
+ __unregister_chrdev(MSR_MAJOR, 0, NR_CPUS, "cpu/msr");
+out:
+ return err;
+}
+
+static void __exit msr_exit(void)
+{
+ int cpu = 0;
+
+ cpu_notifier_register_begin();
+ for_each_online_cpu(cpu)
+ msr_device_destroy(cpu);
+ class_destroy(msr_class);
+ __unregister_chrdev(MSR_MAJOR, 0, NR_CPUS, "cpu/msr");
+ __unregister_hotcpu_notifier(&msr_class_cpu_notifier);
+ cpu_notifier_register_done();
+}
+
+module_init(msr_init);
+module_exit(msr_exit)
+
+MODULE_AUTHOR("H. Peter Anvin <hpa@xxxxxxxxx>");
+MODULE_DESCRIPTION("x86 generic MSR driver");
+MODULE_LICENSE("GPL");
--
1.7.1