diff options
| -rw-r--r-- | arch/x86/kernel/cpuid.c | 45 |
1 files changed, 20 insertions, 25 deletions
diff --git a/arch/x86/kernel/cpuid.c b/arch/x86/kernel/cpuid.c index a63432d800f..c10ebc4b8e4 100644 --- a/arch/x86/kernel/cpuid.c +++ b/arch/x86/kernel/cpuid.c @@ -1,6 +1,6 @@ /* ----------------------------------------------------------------------- * - * - * Copyright 2000 H. Peter Anvin - All Rights Reserved + * + * Copyright 2000-2008 H. Peter Anvin - All Rights Reserved * * 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 @@ -17,6 +17,10 @@ * and then read in chunks of 16 bytes. A larger size means multiple * reads of consecutive levels. * + * The lower 32 bits of the file position is used as the incoming %eax, + * and the upper 32 bits of the file position as the incoming %ecx, + * the latter intended for "counting" eax levels like eax=4. + * * This driver uses /dev/cpu/%d/cpuid where %d is the minor number, and on * an SMP box will direct the access to CPU %d. */ @@ -43,27 +47,16 @@ static struct class *cpuid_class; -struct cpuid_command { - u32 reg; - u32 *data; +struct cpuid_regs { + u32 eax, ebx, ecx, edx; }; static void cpuid_smp_cpuid(void *cmd_block) { - struct cpuid_command *cmd = cmd_block; - - cpuid(cmd->reg, &cmd->data[0], &cmd->data[1], &cmd->data[2], - &cmd->data[3]); -} - -static inline void do_cpuid(int cpu, u32 reg, u32 * data) -{ - struct cpuid_command cmd; + struct cpuid_regs *cmd = (struct cpuid_regs *)cmd_block; - cmd.reg = reg; - cmd.data = data; - - smp_call_function_single(cpu, cpuid_smp_cpuid, &cmd, 1, 1); + cpuid_count(cmd->eax, cmd->ecx, + &cmd->eax, &cmd->ebx, &cmd->ecx, &cmd->edx); } static loff_t cpuid_seek(struct file *file, loff_t offset, int orig) @@ -93,19 +86,21 @@ static ssize_t cpuid_read(struct file *file, char __user *buf, size_t count, loff_t * ppos) { char __user *tmp = buf; - u32 data[4]; - u32 reg = *ppos; + struct cpuid_regs cmd; int cpu = iminor(file->f_path.dentry->d_inode); + u64 pos = *ppos; if (count % 16) return -EINVAL; /* Invalid chunk size */ for (; count; count -= 16) { - do_cpuid(cpu, reg, data); - if (copy_to_user(tmp, &data, 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; tmp += 16; - *ppos = reg++; + *ppos = ++pos; } return tmp - buf; @@ -193,7 +188,7 @@ static int __init cpuid_init(void) } for_each_online_cpu(i) { err = cpuid_device_create(i); - if (err != 0) + if (err != 0) goto out_class; } register_hotcpu_notifier(&cpuid_class_cpu_notifier); @@ -208,7 +203,7 @@ out_class: } class_destroy(cpuid_class); out_chrdev: - unregister_chrdev(CPUID_MAJOR, "cpu/cpuid"); + unregister_chrdev(CPUID_MAJOR, "cpu/cpuid"); out: return err; } |