x86, microcode rework, v2

this is a rework of the microcode splitup in tip/x86/microcode

(1) I think this new interface is cleaner (look at the changes
    in 'struct microcode_ops' in microcode.h);

(2) it's -64 lines of code;

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 155 insertions, 174 deletions

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index d606a05545ca..6815837a7753 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -59,7 +59,7 @@ MODULE_LICENSE("GPL v2");
 /* serialize access to the physical write */
 static DEFINE_SPINLOCK(microcode_update_lock);
 
-struct equiv_cpu_entry *equiv_cpu_table;
+static struct equiv_cpu_entry *equiv_cpu_table;
 
 static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
 {
@@ -83,36 +83,37 @@ static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
         return 0;
 }
 
-static int get_matching_microcode_amd(void *mc, int cpu)
+static int get_matching_microcode(int cpu, void *mc, int rev)
 {
-        struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
         struct microcode_header_amd *mc_header = mc;
-        unsigned long total_size = get_totalsize(mc_header);
-        void *new_mc;
         struct pci_dev *nb_pci_dev, *sb_pci_dev;
         unsigned int current_cpu_id;
         unsigned int equiv_cpu_id = 0x00;
         unsigned int i = 0;
 
-        /* We should bind the task to the CPU */
-        BUG_ON(cpu != raw_smp_processor_id());
-
-        /* This is a tricky part. We might be called from a write operation */
-        /* to the device file instead of the usual process of firmware */
-        /* loading. This routine needs to be able to distinguish both */
-/* cases. This is done by checking if there alread is a equivalent */
-        /* CPU table installed. If not, we're written through */
-        /* /dev/cpu/microcode. */
-/* Since we ignore all checks. The error case in which going through */
-/* firmware loading and that table is not loaded has already been */
-        /* checked earlier. */
+        /*
+         * dimm: do we need this? Why an update via /dev/... is different
+         * from the one via firmware?
+         *
+         * This is a tricky part. We might be called from a write operation
+         * to the device file instead of the usual process of firmware
+         * loading. This routine needs to be able to distinguish both
+         * cases. This is done by checking if there alread is a equivalent
+         * CPU table installed. If not, we're written through
+         * /dev/cpu/microcode.
+         * Since we ignore all checks. The error case in which going through
+         * firmware loading and that table is not loaded has already been
+         * checked earlier.
+         */
+        BUG_ON(equiv_cpu_table == NULL);
+#if 0
         if (equiv_cpu_table == NULL) {
                 printk(KERN_INFO "microcode: CPU%d microcode update with "
                        "version 0x%x (current=0x%x)\n",
                        cpu, mc_header->patch_id, uci->cpu_sig.rev);
                 goto out;
         }
-
+#endif
         current_cpu_id = cpuid_eax(0x00000001);
 
         while (equiv_cpu_table[i].installed_cpu != 0) {
@@ -175,27 +176,9 @@ static int get_matching_microcode_amd(void *mc, int cpu)
                 pci_dev_put(sb_pci_dev);
         }
 
-        if (mc_header->patch_id <= uci->cpu_sig.rev)
+        if (mc_header->patch_id <= rev)
                 return 0;
 
-        printk(KERN_INFO "microcode: CPU%d found a matching microcode "
-               "update with version 0x%x (current=0x%x)\n",
-               cpu, mc_header->patch_id, uci->cpu_sig.rev);
-
-out:
-        new_mc = vmalloc(UCODE_MAX_SIZE);
-        if (!new_mc) {
-                printk(KERN_ERR "microcode: error, can't allocate memory\n");
-                return -ENOMEM;
-        }
-        memset(new_mc, 0, UCODE_MAX_SIZE);
-
-        /* free previous update file */
-        vfree(uci->mc.mc_amd);
-
-        memcpy(new_mc, mc, total_size);
-
-        uci->mc.mc_amd = new_mc;
         return 1;
 }
 
@@ -245,104 +228,65 @@ static void apply_microcode_amd(int cpu)
         uci->cpu_sig.rev = rev;
 }
 
-#ifdef CONFIG_MICROCODE_OLD_INTERFACE
-extern void __user *user_buffer;        /* user area microcode data buffer */
-extern unsigned int user_buffer_size;   /* it's size */
-
-static long get_next_ucode_amd(void **mc, long offset)
-{
-        struct microcode_header_amd mc_header;
-        unsigned long total_size;
-
-        /* No more data */
-        if (offset >= user_buffer_size)
-                return 0;
-        if (copy_from_user(&mc_header, user_buffer + offset, MC_HEADER_SIZE)) {
-                printk(KERN_ERR "microcode: error! Can not read user data\n");
-                return -EFAULT;
-        }
-        total_size = get_totalsize(&mc_header);
-        if (offset + total_size > user_buffer_size) {
-                printk(KERN_ERR "microcode: error! Bad total size in microcode "
-                       "data file\n");
-                return -EINVAL;
-        }
-        *mc = vmalloc(UCODE_MAX_SIZE);
-        if (!*mc)
-                return -ENOMEM;
-        memset(*mc, 0, UCODE_MAX_SIZE);
-
-        if (copy_from_user(*mc, user_buffer + offset, total_size)) {
-                printk(KERN_ERR "microcode: error! Can not read user data\n");
-                vfree(*mc);
-                return -EFAULT;
-        }
-        return offset + total_size;
-}
-#else
-#define get_next_ucode_amd() NULL
-#endif
-
-static long get_next_ucode_from_buffer_amd(void **mc, void *buf,
-                                       unsigned long size, long offset)
+static void * get_next_ucode(u8 *buf, unsigned int size,
+                        int (*get_ucode_data)(void *, const void *, size_t),
+                        unsigned int *mc_size)
 {
-        struct microcode_header_amd *mc_header;
-        unsigned long total_size;
-        unsigned char *buf_pos = buf;
+        unsigned int total_size;
+#define UCODE_UNKNOWN_HDR       8
+        u8 hdr[UCODE_UNKNOWN_HDR];
+        void *mc;
 
-        /* No more data */
-        if (offset >= size)
-                return 0;
+        if (get_ucode_data(hdr, buf, UCODE_UNKNOWN_HDR))
+                return NULL;
 
-        if (buf_pos[offset] != UCODE_UCODE_TYPE) {
+        if (hdr[0] != UCODE_UCODE_TYPE) {
                 printk(KERN_ERR "microcode: error! "
                        "Wrong microcode payload type field\n");
-                return -EINVAL;
+                return NULL;
         }
 
-        mc_header = (struct microcode_header_amd *)(&buf_pos[offset+8]);
+        /* Why not by means of get_totalsize(hdr)? */
+        total_size = (unsigned long) (hdr[4] + (hdr[5] << 8));
 
-        total_size = (unsigned long) (buf_pos[offset+4] +
-                                      (buf_pos[offset+5] << 8));
+        printk(KERN_INFO "microcode: size %u, total_size %u\n",
+                size, total_size);
 
-        printk(KERN_INFO "microcode: size %lu, total_size %lu, offset %ld\n",
-                size, total_size, offset);
-
-        if (offset + total_size > size) {
+        if (total_size > size || total_size > UCODE_MAX_SIZE) {
                 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
-                return -EINVAL;
+                return NULL;
         }
 
-        *mc = vmalloc(UCODE_MAX_SIZE);
-        if (!*mc) {
-                printk(KERN_ERR "microcode: error! "
-                       "Can not allocate memory for microcode patch\n");
-                return -ENOMEM;
+        mc = vmalloc(UCODE_MAX_SIZE);
+        if (mc) {
+                memset(mc, 0, UCODE_MAX_SIZE);
+                if (get_ucode_data(mc, buf + UCODE_UNKNOWN_HDR, total_size)) {
+                        vfree(mc);
+                        mc = NULL;
+                } else
+                        *mc_size = total_size + UCODE_UNKNOWN_HDR;
         }
-
-        memset(*mc, 0, UCODE_MAX_SIZE);
-        memcpy(*mc, buf + offset + 8, total_size);
-
-        return offset + total_size + 8;
+#undef UCODE_UNKNOWN_HDR
+        return mc;
 }
 
-static long install_equiv_cpu_table(void *buf, unsigned long size, long offset)
+
+static int install_equiv_cpu_table(u8 *buf,
+                int (*get_ucode_data)(void *, const void *, size_t))
 {
-        unsigned int *buf_pos = buf;
+#define UCODE_HEADER_SIZE       12
+        u8 *hdr[UCODE_HEADER_SIZE];
+        unsigned int *buf_pos = (unsigned int *)hdr;
+        unsigned long size;
 
-        /* No more data */
-        if (offset >= size)
+        if (get_ucode_data(&hdr, buf, UCODE_HEADER_SIZE))
                 return 0;
 
-        if (buf_pos[1] != UCODE_EQUIV_CPU_TABLE_TYPE) {
-                printk(KERN_ERR "microcode: error! "
-                       "Wrong microcode equivalnet cpu table type field\n");
-                return 0;
-        }
+        size = buf_pos[2];
 
-        if (size == 0) {
+        if (buf_pos[1] != UCODE_EQUIV_CPU_TABLE_TYPE || !size) {
                 printk(KERN_ERR "microcode: error! "
-                       "Wrong microcode equivalnet cpu table length\n");
+                       "Wrong microcode equivalnet cpu table\n");
                 return 0;
         }
 
@@ -352,79 +296,118 @@ static long install_equiv_cpu_table(void *buf, unsigned long size, long offset)
                 return 0;
         }
 
-        memset(equiv_cpu_table, 0, size);
-        memcpy(equiv_cpu_table, &buf_pos[3], size);
+        buf += UCODE_HEADER_SIZE;
+        if (get_ucode_data(equiv_cpu_table, buf, size)) {
+                vfree(equiv_cpu_table);
+                return 0;
+        }
 
-        return size + 12; /* add header length */
+        return size + UCODE_HEADER_SIZE; /* add header length */
+#undef UCODE_HEADER_SIZE
 }
 
-/* fake device for request_firmware */
-extern struct platform_device *microcode_pdev;
-
-static int cpu_request_microcode_amd(int cpu)
+static void free_equiv_cpu_table(void)
 {
-        char name[30];
-        const struct firmware *firmware;
-        void *buf;
-        unsigned int *buf_pos;
-        unsigned long size;
-        long offset = 0;
-        int error;
-        void *mc;
-
-        /* We should bind the task to the CPU */
-        BUG_ON(cpu != raw_smp_processor_id());
-
-        sprintf(name, "amd-ucode/microcode_amd.bin");
-        error = request_firmware(&firmware, "amd-ucode/microcode_amd.bin",
-                                 &microcode_pdev->dev);
-        if (error) {
-                printk(KERN_ERR "microcode: ucode data file %s load failed\n",
-                       name);
-                return error;
-        }
-
-        buf_pos = (unsigned int *)firmware->data;
-        buf = (void *)firmware->data;
-        size = firmware->size;
-
-        if (buf_pos[0] != UCODE_MAGIC) {
-                printk(KERN_ERR "microcode: error! Wrong microcode patch file magic\n");
-                return -EINVAL;
+        if (equiv_cpu_table) {
+                vfree(equiv_cpu_table);
+                equiv_cpu_table = NULL;
         }
+}
 
-        offset = install_equiv_cpu_table(buf, buf_pos[2], offset);
+static int generic_load_microcode(int cpu, void *data, size_t size,
+                int (*get_ucode_data)(void *, const void *, size_t))
+{
+        struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+        u8 *ucode_ptr = data, *new_mc = NULL, *mc;
+        int new_rev = uci->cpu_sig.rev;
+        unsigned int leftover;
+        unsigned long offset;
 
+        offset = install_equiv_cpu_table(ucode_ptr, get_ucode_data);
         if (!offset) {
                 printk(KERN_ERR "microcode: installing equivalent cpu table failed\n");
                 return -EINVAL;
         }
 
-        while ((offset =
-                get_next_ucode_from_buffer_amd(&mc, buf, size, offset)) > 0) {
-                error = get_matching_microcode_amd(mc, cpu);
-                if (error < 0)
+        ucode_ptr += offset;
+        leftover = size - offset;
+
+        while (leftover) {
+                unsigned int mc_size;
+                struct microcode_header_amd *mc_header;
+
+                mc = get_next_ucode(ucode_ptr, leftover, get_ucode_data, &mc_size);
+                if (!mc)
                         break;
-                /*
-                 * It's possible the data file has multiple matching ucode,
-                 * lets keep searching till the latest version
-                 */
-                if (error == 1) {
-                        apply_microcode_amd(cpu);
-                        error = 0;
-                }
-                vfree(mc);
+
+                mc_header = (struct microcode_header_amd *)mc;
+                if (get_matching_microcode(cpu, mc, new_rev)) {
+                        new_rev = mc_header->patch_id;
+                        new_mc  = mc;
+                } else 
+                        vfree(mc);
+
+                ucode_ptr += mc_size;
+                leftover  -= mc_size;
         }
-        if (offset > 0) {
-                vfree(mc);
-                vfree(equiv_cpu_table);
-                equiv_cpu_table = NULL;
+
+        if (new_mc) {
+                if (!leftover) {
+                        if (uci->mc.mc_amd)
+                                vfree(uci->mc.mc_amd);
+                        uci->mc.mc_amd = (struct microcode_amd *)new_mc;
+                        pr_debug("microcode: CPU%d found a matching microcode update with"
+                                " version 0x%x (current=0x%x)\n",
+                                cpu, uci->mc.mc_amd->hdr.patch_id, uci->cpu_sig.rev);
+                } else
+                        vfree(new_mc);
         }
-        if (offset < 0)
-                error = offset;
+
+        free_equiv_cpu_table();
+
+        return (int)leftover;
+}
+
+static int get_ucode_fw(void *to, const void *from, size_t n)
+{
+        memcpy(to, from, n);
+        return 0;
+}
+
+static int request_microcode_fw(int cpu, struct device *device)
+{
+        const char *fw_name = "amd-ucode/microcode_amd.bin";
+        const struct firmware *firmware;
+        int ret;
+
+        /* We should bind the task to the CPU */
+        BUG_ON(cpu != raw_smp_processor_id());
+
+        ret = request_firmware(&firmware, fw_name, device);
+        if (ret) {
+                printk(KERN_ERR "microcode: ucode data file %s load failed\n", fw_name);
+                return ret;
+        }
+
+        ret = generic_load_microcode(cpu, (void*)firmware->data, firmware->size,
+                        &get_ucode_fw);
+
         release_firmware(firmware);
 
-        return error;
+        return ret;
+}
+
+static int get_ucode_user(void *to, const void *from, size_t n)
+{
+        return copy_from_user(to, from, n);
+}
+
+static int request_microcode_user(int cpu, const void __user *buf, size_t size)
+{
+        /* We should bind the task to the CPU */
+        BUG_ON(cpu != raw_smp_processor_id());
+
+        return generic_load_microcode(cpu, (void*)buf, size, &get_ucode_user);
 }
 
 static void microcode_fini_cpu_amd(int cpu)
@@ -436,10 +419,8 @@ static void microcode_fini_cpu_amd(int cpu)
 }
 
 static struct microcode_ops microcode_amd_ops = {
-        .get_next_ucode                   = get_next_ucode_amd,
-        .get_matching_microcode           = get_matching_microcode_amd,
-        .microcode_sanity_check           = NULL,
-        .cpu_request_microcode            = cpu_request_microcode_amd,
+        .request_microcode_user           = request_microcode_user,
+        .request_microcode_fw             = request_microcode_fw,
         .collect_cpu_info                 = collect_cpu_info_amd,
         .apply_microcode                  = apply_microcode_amd,
         .microcode_fini_cpu               = microcode_fini_cpu_amd,