x86: major refactoring

Refactored code by introducing a two-module solution.

There is one general module in which vendor specific modules can hook into.
However, that is exclusive, there is only one vendor specific module
allowed at a time. A CPU vendor check makes sure only the correct
module for the underlying system gets called.

Functinally in terms of patch loading itself there are no changes. This
refactoring provides a basis for future implementations of other vendors'
patch loaders.

Signed-off-by: Peter Oruba <peter.oruba@amd.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

3 files changed, 89 insertions, 45 deletions

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index abb32aed7f4b..f2f9f6da8c18 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -51,8 +51,8 @@ obj-$(CONFIG_X86_BIOS_REBOOT)	+= reboot.o
 obj-$(CONFIG_MCA)               += mca_32.o
 obj-$(CONFIG_X86_MSR)           += msr.o
 obj-$(CONFIG_X86_CPUID)         += cpuid.o
-obj-$(CONFIG_MICROCODE)         += ucode.o
-ucode-objs                      := microcode.o microcode_intel.o
+obj-$(CONFIG_MICROCODE)         += microcode.o
+obj-$(CONFIG_MICROCODE_INTEL)   += microcode_intel.o
 obj-$(CONFIG_PCI)               += early-quirks.o
 apm-y                           := apm_32.o
 obj-$(CONFIG_APM)               += apm.o
diff --git a/arch/x86/kernel/microcode.c b/arch/x86/kernel/microcode.c
index c1047d7f7ede..1e42e79ca694 100644
--- a/arch/x86/kernel/microcode.c
+++ b/arch/x86/kernel/microcode.c
@@ -99,25 +99,22 @@ MODULE_DESCRIPTION("Microcode Update Driver");
 MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
 MODULE_LICENSE("GPL");
 
-#define MICROCODE_VERSION       "1.14a"
+#define MICROCODE_VERSION       "2.00"
 
-/* no concurrent ->write()s are allowed on /dev/cpu/microcode */
-DEFINE_MUTEX(microcode_mutex);
+struct microcode_ops *microcode_ops;
 
-struct ucode_cpu_info ucode_cpu_info[NR_CPUS];
+/* no concurrent ->write()s are allowed on /dev/cpu/microcode */
+static DEFINE_MUTEX(microcode_mutex);
+EXPORT_SYMBOL_GPL(microcode_mutex);
 
-extern long get_next_ucode(void **mc, long offset);
-extern int microcode_sanity_check(void *mc);
-extern int get_matching_microcode(void *mc, int cpu);
-extern void collect_cpu_info(int cpu_num);
-extern int cpu_request_microcode(int cpu);
-extern void microcode_fini_cpu(int cpu);
-extern void apply_microcode(int cpu);
-extern int apply_microcode_check_cpu(int cpu);
+static struct ucode_cpu_info ucode_cpu_info[NR_CPUS];
+EXPORT_SYMBOL_GPL(ucode_cpu_info);
 
 #ifdef CONFIG_MICROCODE_OLD_INTERFACE
-void __user *user_buffer;       /* user area microcode data buffer */
-unsigned int user_buffer_size;  /* it's size */
+static void __user *user_buffer;        /* user area microcode data buffer */
+EXPORT_SYMBOL_GPL(user_buffer);
+static unsigned int user_buffer_size;   /* it's size */
+EXPORT_SYMBOL_GPL(user_buffer_size);
 
 static int do_microcode_update (void)
 {
@@ -130,8 +127,8 @@ static int do_microcode_update (void)
 
         old = current->cpus_allowed;
 
-        while ((cursor = get_next_ucode(&new_mc, cursor)) > 0) {
-                error = microcode_sanity_check(new_mc);
+        while ((cursor = microcode_ops->get_next_ucode(&new_mc, cursor)) > 0) {
+                error = microcode_ops->microcode_sanity_check(new_mc);
                 if (error)
                         goto out;
                 /*
@@ -145,11 +142,12 @@ static int do_microcode_update (void)
                                 continue;
                         cpumask_of_cpu_ptr_next(newmask, cpu);
                         set_cpus_allowed_ptr(current, newmask);
-                        error = get_maching_microcode(new_mc, cpu);
+                        error = microcode_ops->get_matching_microcode(new_mc,
+                                                                      cpu);
                         if (error < 0)
                                 goto out;
                         if (error == 1)
-                                apply_microcode(cpu);
+                                microcode_ops->apply_microcode(cpu);
                 }
                 vfree(new_mc);
         }
@@ -232,7 +230,8 @@ MODULE_ALIAS_MISCDEV(MICROCODE_MINOR);
 #endif
 
 /* fake device for request_firmware */
-struct platform_device *microcode_pdev;
+static struct platform_device *microcode_pdev;
+EXPORT_SYMBOL_GPL(microcode_pdev);
 
 static void microcode_init_cpu(int cpu, int resume)
 {
@@ -244,9 +243,9 @@ static void microcode_init_cpu(int cpu, int resume)
 
         set_cpus_allowed_ptr(current, newmask);
         mutex_lock(&microcode_mutex);
-        collect_cpu_info(cpu);
+        microcode_ops->collect_cpu_info(cpu);
         if (uci->valid && system_state == SYSTEM_RUNNING && !resume)
-                cpu_request_microcode(cpu);
+                microcode_ops->cpu_request_microcode(cpu);
         mutex_unlock(&microcode_mutex);
         set_cpus_allowed_ptr(current, &old);
 }
@@ -274,7 +273,7 @@ static ssize_t reload_store(struct sys_device *dev,
 
                 mutex_lock(&microcode_mutex);
                 if (uci->valid)
-                        err = cpu_request_microcode(cpu);
+                        err = microcode_ops->cpu_request_microcode(cpu);
                 mutex_unlock(&microcode_mutex);
                 put_online_cpus();
                 set_cpus_allowed_ptr(current, &old);
@@ -349,7 +348,7 @@ static int mc_sysdev_remove(struct sys_device *sys_dev)
                 return 0;
 
         pr_debug("microcode: CPU%d removed\n", cpu);
-        microcode_fini_cpu(cpu);
+        microcode_ops->microcode_fini_cpu(cpu);
         sysfs_remove_group(&sys_dev->kobj, &mc_attr_group);
         return 0;
 }
@@ -362,7 +361,7 @@ static int mc_sysdev_resume(struct sys_device *dev)
                 return 0;
         pr_debug("microcode: CPU%d resumed\n", cpu);
         /* only CPU 0 will apply ucode here */
-        apply_microcode(0);
+        microcode_ops->apply_microcode(0);
         return 0;
 }
 
@@ -382,7 +381,7 @@ mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
         switch (action) {
         case CPU_UP_CANCELED_FROZEN:
                 /* The CPU refused to come up during a system resume */
-                microcode_fini_cpu(cpu);
+                microcode_ops->microcode_fini_cpu(cpu);
                 break;
         case CPU_ONLINE:
         case CPU_DOWN_FAILED:
@@ -390,9 +389,9 @@ mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
                 break;
         case CPU_ONLINE_FROZEN:
                 /* System-wide resume is in progress, try to apply microcode */
-                if (apply_microcode_check_cpu(cpu)) {
+                if (microcode_ops->apply_microcode_check_cpu(cpu)) {
                         /* The application of microcode failed */
-                        microcode_fini_cpu(cpu);
+                        microcode_ops->microcode_fini_cpu(cpu);
                         __mc_sysdev_add(sys_dev, 1);
                         break;
                 }
@@ -416,12 +415,17 @@ static struct notifier_block __refdata mc_cpu_notifier = {
         .notifier_call = mc_cpu_callback,
 };
 
-static int __init microcode_init (void)
+static int microcode_init(void *opaque, struct module *module)
 {
+        struct microcode_ops *ops = (struct microcode_ops *)opaque;
         int error;
 
-        printk(KERN_INFO
-                "IA-32 Microcode Update Driver: v" MICROCODE_VERSION " <tigran@aivazian.fsnet.co.uk>\n");
+        if (microcode_ops) {
+                printk(KERN_ERR "microcode: already loaded the other module\n");
+                return -EEXIST;
+        }
+
+        microcode_ops = ops;
 
         error = microcode_dev_init();
         if (error)
@@ -443,8 +447,15 @@ static int __init microcode_init (void)
         }
 
         register_hotcpu_notifier(&mc_cpu_notifier);
+
+        printk(KERN_INFO
+               "Microcode Update Driver: v" MICROCODE_VERSION
+               " <tigran@aivazian.fsnet.co.uk>"
+               " <peter.oruba@amd.com>\n");
+
         return 0;
 }
+EXPORT_SYMBOL_GPL(microcode_init);
 
 static void __exit microcode_exit (void)
 {
@@ -457,7 +468,10 @@ static void __exit microcode_exit (void)
         put_online_cpus();
 
         platform_device_unregister(microcode_pdev);
-}
 
-module_init(microcode_init)
-module_exit(microcode_exit)
+        microcode_ops = NULL;
+
+        printk(KERN_INFO
+               "Microcode Update Driver: v" MICROCODE_VERSION " removed.\n");
+}
+EXPORT_SYMBOL_GPL(microcode_exit);
diff --git a/arch/x86/kernel/microcode_intel.c b/arch/x86/kernel/microcode_intel.c
index ca9861bf067e..831db5363dba 100644
--- a/arch/x86/kernel/microcode_intel.c
+++ b/arch/x86/kernel/microcode_intel.c
@@ -127,7 +127,7 @@ extern struct mutex microcode_mutex;
 
 extern struct ucode_cpu_info ucode_cpu_info[NR_CPUS];
 
-void collect_cpu_info(int cpu_num)
+static void collect_cpu_info(int cpu_num)
 {
         struct cpuinfo_x86 *c = &cpu_data(cpu_num);
         struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
@@ -175,7 +175,7 @@ static inline int microcode_update_match(int cpu_num,
         return 1;
 }
 
-int microcode_sanity_check(void *mc)
+static int microcode_sanity_check(void *mc)
 {
         struct microcode_header_intel *mc_header = mc;
         struct extended_sigtable *ext_header = NULL;
@@ -259,7 +259,7 @@ int microcode_sanity_check(void *mc)
  * return 1 - found update
  * return < 0 - error
  */
-int get_matching_microcode(void *mc, int cpu)
+static int get_matching_microcode(void *mc, int cpu)
 {
         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
         struct microcode_header_intel *mc_header = mc;
@@ -288,7 +288,8 @@ int get_matching_microcode(void *mc, int cpu)
         return 0;
 find:
         pr_debug("microcode: CPU%d found a matching microcode update with"
-                 " version 0x%x (current=0x%x)\n", cpu, mc_header->rev, uci->rev);
+                 " version 0x%x (current=0x%x)\n",
+                 cpu, mc_header->rev, uci->rev);
         new_mc = vmalloc(total_size);
         if (!new_mc) {
                 printk(KERN_ERR "microcode: error! Can not allocate memory\n");
@@ -303,7 +304,7 @@ find:
         return 1;
 }
 
-void apply_microcode(int cpu)
+static void apply_microcode(int cpu)
 {
         unsigned long flags;
         unsigned int val[2];
@@ -347,7 +348,7 @@ void apply_microcode(int cpu)
 extern void __user *user_buffer;        /* user area microcode data buffer */
 extern unsigned int user_buffer_size;   /* it's size */
 
-long get_next_ucode(void **mc, long offset)
+static long get_next_ucode(void **mc, long offset)
 {
         struct microcode_header_intel mc_header;
         unsigned long total_size;
@@ -406,7 +407,7 @@ static long get_next_ucode_from_buffer(void **mc, const u8 *buf,
 /* fake device for request_firmware */
 extern struct platform_device *microcode_pdev;
 
-int cpu_request_microcode(int cpu)
+static int cpu_request_microcode(int cpu)
 {
         char name[30];
         struct cpuinfo_x86 *c = &cpu_data(cpu);
@@ -455,7 +456,7 @@ int cpu_request_microcode(int cpu)
         return error;
 }
 
-int apply_microcode_check_cpu(int cpu)
+static int apply_microcode_check_cpu(int cpu)
 {
         struct cpuinfo_x86 *c = &cpu_data(cpu);
         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
@@ -504,13 +505,42 @@ int apply_microcode_check_cpu(int cpu)
         return err;
 }
 
-void microcode_fini_cpu(int cpu)
+static void microcode_fini_cpu(int cpu)
 {
         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
 
         mutex_lock(&microcode_mutex);
         uci->valid = 0;
-        kfree(uci->mc.mc_intel);
+        vfree(uci->mc.mc_intel);
         uci->mc.mc_intel = NULL;
         mutex_unlock(&microcode_mutex);
 }
+
+static struct microcode_ops microcode_intel_ops = {
+        .get_next_ucode                   = get_next_ucode,
+        .get_matching_microcode           = get_matching_microcode,
+        .microcode_sanity_check           = microcode_sanity_check,
+        .apply_microcode_check_cpu        = apply_microcode_check_cpu,
+        .cpu_request_microcode            = cpu_request_microcode,
+        .collect_cpu_info                 = collect_cpu_info,
+        .apply_microcode                  = apply_microcode,
+        .microcode_fini_cpu               = microcode_fini_cpu,
+};
+
+static int __init microcode_intel_module_init(void)
+{
+        struct cpuinfo_x86 *c = &cpu_data(get_cpu());
+
+        if (c->x86_vendor == X86_VENDOR_INTEL)
+                return microcode_init(&microcode_intel_ops, THIS_MODULE);
+        else
+                return -ENODEV;
+}
+
+static void __exit microcode_intel_module_exit(void)
+{
+        microcode_exit();
+}
+
+module_init(microcode_intel_module_init)
+module_exit(microcode_intel_module_exit)