arch/x86/kernel/cpu/cpu_debug.c

   1 /*
   2  * CPU x86 architecture debug code
   3  *
   4  * Copyright(C) 2009 Jaswinder Singh Rajput
   5  *
   6  * For licencing details see kernel-base/COPYING
   7  */
   8
   9 #include <linux/interrupt.h>
  10 #include <linux/compiler.h>
  11 #include <linux/seq_file.h>
  12 #include <linux/debugfs.h>
  13 #include <linux/kprobes.h>
  14 #include <linux/uaccess.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/percpu.h>
  18 #include <linux/signal.h>
  19 #include <linux/errno.h>
  20 #include <linux/sched.h>
  21 #include <linux/types.h>
  22 #include <linux/init.h>
  23 #include <linux/slab.h>
  24 #include <linux/smp.h>
  25
  26 #include <asm/cpu_debug.h>
  27 #include <asm/paravirt.h>
  28 #include <asm/system.h>
  29 #include <asm/traps.h>
  30 #include <asm/apic.h>
  31 #include <asm/desc.h>
  32
  33 static DEFINE_PER_CPU(struct cpu_cpuX_base [CPU_REG_ALL_BIT], cpu_arr);
  34 static DEFINE_PER_CPU(struct cpu_private * [MAX_CPU_FILES], priv_arr);
  35 static DEFINE_PER_CPU(int, cpu_priv_count);
  36
  37 static DEFINE_MUTEX(cpu_debug_lock);
  38
  39 static struct dentry *cpu_debugfs_dir;
  40
  41 static struct cpu_debug_base cpu_base[] = {
  42         { "mc",         CPU_MC,         0       },
  43         { "monitor",    CPU_MONITOR,    0       },
  44         { "time",       CPU_TIME,       0       },
  45         { "pmc",        CPU_PMC,        1       },
  46         { "platform",   CPU_PLATFORM,   0       },
  47         { "apic",       CPU_APIC,       0       },
  48         { "poweron",    CPU_POWERON,    0       },
  49         { "control",    CPU_CONTROL,    0       },
  50         { "features",   CPU_FEATURES,   0       },
  51         { "lastbranch", CPU_LBRANCH,    0       },
  52         { "bios",       CPU_BIOS,       0       },
  53         { "freq",       CPU_FREQ,       0       },
  54         { "mtrr",       CPU_MTRR,       0       },
  55         { "perf",       CPU_PERF,       0       },
  56         { "cache",      CPU_CACHE,      0       },
  57         { "sysenter",   CPU_SYSENTER,   0       },
  58         { "therm",      CPU_THERM,      0       },
  59         { "misc",       CPU_MISC,       0       },
  60         { "debug",      CPU_DEBUG,      0       },
  61         { "pat",        CPU_PAT,        0       },
  62         { "vmx",        CPU_VMX,        0       },
  63         { "call",       CPU_CALL,       0       },
  64         { "base",       CPU_BASE,       0       },
  65         { "ver",        CPU_VER,        0       },
  66         { "conf",       CPU_CONF,       0       },
  67         { "smm",        CPU_SMM,        0       },
  68         { "svm",        CPU_SVM,        0       },
  69         { "osvm",       CPU_OSVM,       0       },
  70         { "tss",        CPU_TSS,        0       },
  71         { "cr",         CPU_CR,         0       },
  72         { "dt",         CPU_DT,         0       },
  73         { "registers",  CPU_REG_ALL,    0       },
  74 };
  75
  76 static struct cpu_file_base cpu_file[] = {
  77         { "index",      CPU_REG_ALL,    0       },
  78         { "value",      CPU_REG_ALL,    1       },
  79 };
  80
  81 /* CPU Registers Range */
  82 static struct cpu_debug_range cpu_reg_range[] = {
  83         { 0x00000000, 0x00000001, CPU_MC,       },
  84         { 0x00000006, 0x00000007, CPU_MONITOR,  },
  85         { 0x00000010, 0x00000010, CPU_TIME,     },
  86         { 0x00000011, 0x00000013, CPU_PMC,      },
  87         { 0x00000017, 0x00000017, CPU_PLATFORM, },
  88         { 0x0000001B, 0x0000001B, CPU_APIC,     },
  89         { 0x0000002A, 0x0000002B, CPU_POWERON,  },
  90         { 0x0000002C, 0x0000002C, CPU_FREQ,     },
  91         { 0x0000003A, 0x0000003A, CPU_CONTROL,  },
  92         { 0x00000040, 0x00000047, CPU_LBRANCH,  },
  93         { 0x00000060, 0x00000067, CPU_LBRANCH,  },
  94         { 0x00000079, 0x00000079, CPU_BIOS,     },
  95         { 0x00000088, 0x0000008A, CPU_CACHE,    },
  96         { 0x0000008B, 0x0000008B, CPU_BIOS,     },
  97         { 0x0000009B, 0x0000009B, CPU_MONITOR,  },
  98         { 0x000000C1, 0x000000C4, CPU_PMC,      },
  99         { 0x000000CD, 0x000000CD, CPU_FREQ,     },
 100         { 0x000000E7, 0x000000E8, CPU_PERF,     },
 101         { 0x000000FE, 0x000000FE, CPU_MTRR,     },
 102
 103         { 0x00000116, 0x0000011E, CPU_CACHE,    },
 104         { 0x00000174, 0x00000176, CPU_SYSENTER, },
 105         { 0x00000179, 0x0000017B, CPU_MC,       },
 106         { 0x00000186, 0x00000189, CPU_PMC,      },
 107         { 0x00000198, 0x00000199, CPU_PERF,     },
 108         { 0x0000019A, 0x0000019A, CPU_TIME,     },
 109         { 0x0000019B, 0x0000019D, CPU_THERM,    },
 110         { 0x000001A0, 0x000001A0, CPU_MISC,     },
 111         { 0x000001C9, 0x000001C9, CPU_LBRANCH,  },
 112         { 0x000001D7, 0x000001D8, CPU_LBRANCH,  },
 113         { 0x000001D9, 0x000001D9, CPU_DEBUG,    },
 114         { 0x000001DA, 0x000001E0, CPU_LBRANCH,  },
 115
 116         { 0x00000200, 0x0000020F, CPU_MTRR,     },
 117         { 0x00000250, 0x00000250, CPU_MTRR,     },
 118         { 0x00000258, 0x00000259, CPU_MTRR,     },
 119         { 0x00000268, 0x0000026F, CPU_MTRR,     },
 120         { 0x00000277, 0x00000277, CPU_PAT,      },
 121         { 0x000002FF, 0x000002FF, CPU_MTRR,     },
 122
 123         { 0x00000300, 0x00000311, CPU_PMC,      },
 124         { 0x00000345, 0x00000345, CPU_PMC,      },
 125         { 0x00000360, 0x00000371, CPU_PMC,      },
 126         { 0x0000038D, 0x00000390, CPU_PMC,      },
 127         { 0x000003A0, 0x000003BE, CPU_PMC,      },
 128         { 0x000003C0, 0x000003CD, CPU_PMC,      },
 129         { 0x000003E0, 0x000003E1, CPU_PMC,      },
 130         { 0x000003F0, 0x000003F2, CPU_PMC,      },
 131
 132         { 0x00000400, 0x00000417, CPU_MC,       },
 133         { 0x00000480, 0x0000048B, CPU_VMX,      },
 134
 135         { 0x00000600, 0x00000600, CPU_DEBUG,    },
 136         { 0x00000680, 0x0000068F, CPU_LBRANCH,  },
 137         { 0x000006C0, 0x000006CF, CPU_LBRANCH,  },
 138
 139         { 0x000107CC, 0x000107D3, CPU_PMC,      },
 140
 141         { 0xC0000080, 0xC0000080, CPU_FEATURES, },
 142         { 0xC0000081, 0xC0000084, CPU_CALL,     },
 143         { 0xC0000100, 0xC0000102, CPU_BASE,     },
 144         { 0xC0000103, 0xC0000103, CPU_TIME,     },
 145
 146         { 0xC0010000, 0xC0010007, CPU_PMC,      },
 147         { 0xC0010010, 0xC0010010, CPU_CONF,     },
 148         { 0xC0010015, 0xC0010015, CPU_CONF,     },
 149         { 0xC0010016, 0xC001001A, CPU_MTRR,     },
 150         { 0xC001001D, 0xC001001D, CPU_MTRR,     },
 151         { 0xC001001F, 0xC001001F, CPU_CONF,     },
 152         { 0xC0010030, 0xC0010035, CPU_BIOS,     },
 153         { 0xC0010044, 0xC0010048, CPU_MC,       },
 154         { 0xC0010050, 0xC0010056, CPU_SMM,      },
 155         { 0xC0010058, 0xC0010058, CPU_CONF,     },
 156         { 0xC0010060, 0xC0010060, CPU_CACHE,    },
 157         { 0xC0010061, 0xC0010068, CPU_SMM,      },
 158         { 0xC0010069, 0xC001006B, CPU_SMM,      },
 159         { 0xC0010070, 0xC0010071, CPU_SMM,      },
 160         { 0xC0010111, 0xC0010113, CPU_SMM,      },
 161         { 0xC0010114, 0xC0010118, CPU_SVM,      },
 162         { 0xC0010140, 0xC0010141, CPU_OSVM,     },
 163         { 0xC0011022, 0xC0011023, CPU_CONF,     },
 164 };
 165
 166 static int is_typeflag_valid(unsigned cpu, unsigned flag)
 167 {
 168         int i;
 169
 170         /* Standard Registers should be always valid */
 171         if (flag >= CPU_TSS)
 172                 return 1;
 173
 174         for (i = 0; i < ARRAY_SIZE(cpu_reg_range); i++) {
 175                 if (cpu_reg_range[i].flag == flag)
 176                         return 1;
 177         }
 178
 179         /* Invalid */
 180         return 0;
 181 }
 182
 183 static unsigned get_cpu_range(unsigned cpu, unsigned *min, unsigned *max,
 184                               int index, unsigned flag)
 185 {
 186         if (cpu_reg_range[index].flag == flag) {
 187                 *min = cpu_reg_range[index].min;
 188                 *max = cpu_reg_range[index].max;
 189         } else
 190                 *max = 0;
 191
 192         return *max;
 193 }
 194
 195 /* This function can also be called with seq = NULL for printk */
 196 static void print_cpu_data(struct seq_file *seq, unsigned type,
 197                            u32 low, u32 high)
 198 {
 199         struct cpu_private *priv;
 200         u64 val = high;
 201
 202         if (seq) {
 203                 priv = seq->private;
 204                 if (priv->file) {
 205                         val = (val << 32) | low;
 206                         seq_printf(seq, "0x%llx\n", val);
 207                 } else
 208                         seq_printf(seq, " %08x: %08x_%08x\n",
 209                                    type, high, low);
 210         } else
 211                 printk(KERN_INFO " %08x: %08x_%08x\n", type, high, low);
 212 }
 213
 214 /* This function can also be called with seq = NULL for printk */
 215 static void print_msr(struct seq_file *seq, unsigned cpu, unsigned flag)
 216 {
 217         unsigned msr, msr_min, msr_max;
 218         struct cpu_private *priv;
 219         u32 low, high;
 220         int i;
 221
 222         if (seq) {
 223                 priv = seq->private;
 224                 if (priv->file) {
 225                         if (!rdmsr_safe_on_cpu(priv->cpu, priv->reg,
 226                                                &low, &high))
 227                                 print_cpu_data(seq, priv->reg, low, high);
 228                         return;
 229                 }
 230         }
 231
 232         for (i = 0; i < ARRAY_SIZE(cpu_reg_range); i++) {
 233                 if (!get_cpu_range(cpu, &msr_min, &msr_max, i, flag))
 234                         continue;
 235
 236                 for (msr = msr_min; msr <= msr_max; msr++) {
 237                         if (rdmsr_safe_on_cpu(cpu, msr, &low, &high))
 238                                 continue;
 239                         print_cpu_data(seq, msr, low, high);
 240                 }
 241         }
 242 }
 243
 244 static void print_tss(void *arg)
 245 {
 246         struct pt_regs *regs = task_pt_regs(current);
 247         struct seq_file *seq = arg;
 248         unsigned int seg;
 249
 250         seq_printf(seq, " RAX\t: %016lx\n", regs->ax);
 251         seq_printf(seq, " RBX\t: %016lx\n", regs->bx);
 252         seq_printf(seq, " RCX\t: %016lx\n", regs->cx);
 253         seq_printf(seq, " RDX\t: %016lx\n", regs->dx);
 254
 255         seq_printf(seq, " RSI\t: %016lx\n", regs->si);
 256         seq_printf(seq, " RDI\t: %016lx\n", regs->di);
 257         seq_printf(seq, " RBP\t: %016lx\n", regs->bp);
 258         seq_printf(seq, " ESP\t: %016lx\n", regs->sp);
 259
 260 #ifdef CONFIG_X86_64
 261         seq_printf(seq, " R08\t: %016lx\n", regs->r8);
 262         seq_printf(seq, " R09\t: %016lx\n", regs->r9);
 263         seq_printf(seq, " R10\t: %016lx\n", regs->r10);
 264         seq_printf(seq, " R11\t: %016lx\n", regs->r11);
 265         seq_printf(seq, " R12\t: %016lx\n", regs->r12);
 266         seq_printf(seq, " R13\t: %016lx\n", regs->r13);
 267         seq_printf(seq, " R14\t: %016lx\n", regs->r14);
 268         seq_printf(seq, " R15\t: %016lx\n", regs->r15);
 269 #endif
 270
 271         asm("movl %%cs,%0" : "=r" (seg));
 272         seq_printf(seq, " CS\t:             %04x\n", seg);
 273         asm("movl %%ds,%0" : "=r" (seg));
 274         seq_printf(seq, " DS\t:             %04x\n", seg);
 275         seq_printf(seq, " SS\t:             %04lx\n", regs->ss & 0xffff);
 276         asm("movl %%es,%0" : "=r" (seg));
 277         seq_printf(seq, " ES\t:             %04x\n", seg);
 278         asm("movl %%fs,%0" : "=r" (seg));
 279         seq_printf(seq, " FS\t:             %04x\n", seg);
 280         asm("movl %%gs,%0" : "=r" (seg));
 281         seq_printf(seq, " GS\t:             %04x\n", seg);
 282
 283         seq_printf(seq, " EFLAGS\t: %016lx\n", regs->flags);
 284
 285         seq_printf(seq, " EIP\t: %016lx\n", regs->ip);
 286 }
 287
 288 static void print_cr(void *arg)
 289 {
 290         struct seq_file *seq = arg;
 291
 292         seq_printf(seq, " cr0\t: %016lx\n", read_cr0());
 293         seq_printf(seq, " cr2\t: %016lx\n", read_cr2());
 294         seq_printf(seq, " cr3\t: %016lx\n", read_cr3());
 295         seq_printf(seq, " cr4\t: %016lx\n", read_cr4_safe());
 296 #ifdef CONFIG_X86_64
 297         seq_printf(seq, " cr8\t: %016lx\n", read_cr8());
 298 #endif
 299 }
 300
 301 static void print_desc_ptr(char *str, struct seq_file *seq, struct desc_ptr dt)
 302 {
 303         seq_printf(seq, " %s\t: %016llx\n", str, (u64)(dt.address | dt.size));
 304 }
 305
 306 static void print_dt(void *seq)
 307 {
 308         struct desc_ptr dt;
 309         unsigned long ldt;
 310
 311         /* IDT */
 312         store_idt((struct desc_ptr *)&dt);
 313         print_desc_ptr("IDT", seq, dt);
 314
 315         /* GDT */
 316         store_gdt((struct desc_ptr *)&dt);
 317         print_desc_ptr("GDT", seq, dt);
 318
 319         /* LDT */
 320         store_ldt(ldt);
 321         seq_printf(seq, " LDT\t: %016lx\n", ldt);
 322
 323         /* TR */
 324         store_tr(ldt);
 325         seq_printf(seq, " TR\t: %016lx\n", ldt);
 326 }
 327
 328 static void print_dr(void *arg)
 329 {
 330         struct seq_file *seq = arg;
 331         unsigned long dr;
 332         int i;
 333
 334         for (i = 0; i < 8; i++) {
 335                 /* Ignore db4, db5 */
 336                 if ((i == 4) || (i == 5))
 337                         continue;
 338                 get_debugreg(dr, i);
 339                 seq_printf(seq, " dr%d\t: %016lx\n", i, dr);
 340         }
 341
 342         seq_printf(seq, "\n MSR\t:\n");
 343 }
 344
 345 static void print_apic(void *arg)
 346 {
 347         struct seq_file *seq = arg;
 348
 349 #ifdef CONFIG_X86_LOCAL_APIC
 350         seq_printf(seq, " LAPIC\t:\n");
 351         seq_printf(seq, " ID\t\t: %08x\n",  apic_read(APIC_ID) >> 24);
 352         seq_printf(seq, " LVR\t\t: %08x\n",  apic_read(APIC_LVR));
 353         seq_printf(seq, " TASKPRI\t: %08x\n",  apic_read(APIC_TASKPRI));
 354         seq_printf(seq, " ARBPRI\t\t: %08x\n",  apic_read(APIC_ARBPRI));
 355         seq_printf(seq, " PROCPRI\t: %08x\n",  apic_read(APIC_PROCPRI));
 356         seq_printf(seq, " LDR\t\t: %08x\n",  apic_read(APIC_LDR));
 357         seq_printf(seq, " DFR\t\t: %08x\n",  apic_read(APIC_DFR));
 358         seq_printf(seq, " SPIV\t\t: %08x\n",  apic_read(APIC_SPIV));
 359         seq_printf(seq, " ISR\t\t: %08x\n",  apic_read(APIC_ISR));
 360         seq_printf(seq, " ESR\t\t: %08x\n",  apic_read(APIC_ESR));
 361         seq_printf(seq, " ICR\t\t: %08x\n",  apic_read(APIC_ICR));
 362         seq_printf(seq, " ICR2\t\t: %08x\n",  apic_read(APIC_ICR2));
 363         seq_printf(seq, " LVTT\t\t: %08x\n",  apic_read(APIC_LVTT));
 364         seq_printf(seq, " LVTTHMR\t: %08x\n",  apic_read(APIC_LVTTHMR));
 365         seq_printf(seq, " LVTPC\t\t: %08x\n",  apic_read(APIC_LVTPC));
 366         seq_printf(seq, " LVT0\t\t: %08x\n",  apic_read(APIC_LVT0));
 367         seq_printf(seq, " LVT1\t\t: %08x\n",  apic_read(APIC_LVT1));
 368         seq_printf(seq, " LVTERR\t\t: %08x\n",  apic_read(APIC_LVTERR));
 369         seq_printf(seq, " TMICT\t\t: %08x\n",  apic_read(APIC_TMICT));
 370         seq_printf(seq, " TMCCT\t\t: %08x\n",  apic_read(APIC_TMCCT));
 371         seq_printf(seq, " TDCR\t\t: %08x\n",  apic_read(APIC_TDCR));
 372         if (boot_cpu_has(X86_FEATURE_EXTAPIC)) {
 373                 unsigned int i, v, maxeilvt;
 374
 375                 v = apic_read(APIC_EFEAT);
 376                 maxeilvt = (v >> 16) & 0xff;
 377                 seq_printf(seq, " EFEAT\t\t: %08x\n", v);
 378                 seq_printf(seq, " ECTRL\t\t: %08x\n", apic_read(APIC_ECTRL));
 379
 380                 for (i = 0; i < maxeilvt; i++) {
 381                         v = apic_read(APIC_EILVTn(i));
 382                         seq_printf(seq, " EILVT%d\t\t: %08x\n", i, v);
 383                 }
 384         }
 385 #endif /* CONFIG_X86_LOCAL_APIC */
 386         seq_printf(seq, "\n MSR\t:\n");
 387 }
 388
 389 static int cpu_seq_show(struct seq_file *seq, void *v)
 390 {
 391         struct cpu_private *priv = seq->private;
 392
 393         if (priv == NULL)
 394                 return -EINVAL;
 395
 396         switch (cpu_base[priv->type].flag) {
 397         case CPU_TSS:
 398                 smp_call_function_single(priv->cpu, print_tss, seq, 1);
 399                 break;
 400         case CPU_CR:
 401                 smp_call_function_single(priv->cpu, print_cr, seq, 1);
 402                 break;
 403         case CPU_DT:
 404                 smp_call_function_single(priv->cpu, print_dt, seq, 1);
 405                 break;
 406         case CPU_DEBUG:
 407                 if (priv->file == CPU_INDEX_BIT)
 408                         smp_call_function_single(priv->cpu, print_dr, seq, 1);
 409                 print_msr(seq, priv->cpu, cpu_base[priv->type].flag);
 410                 break;
 411         case CPU_APIC:
 412                 if (priv->file == CPU_INDEX_BIT)
 413                         smp_call_function_single(priv->cpu, print_apic, seq, 1);
 414                 print_msr(seq, priv->cpu, cpu_base[priv->type].flag);
 415                 break;
 416
 417         default:
 418                 print_msr(seq, priv->cpu, cpu_base[priv->type].flag);
 419                 break;
 420         }
 421         seq_printf(seq, "\n");
 422
 423         return 0;
 424 }
 425
 426 static void *cpu_seq_start(struct seq_file *seq, loff_t *pos)
 427 {
 428         if (*pos == 0) /* One time is enough ;-) */
 429                 return seq;
 430
 431         return NULL;
 432 }
 433
 434 static void *cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 435 {
 436         (*pos)++;
 437
 438         return cpu_seq_start(seq, pos);
 439 }
 440
 441 static void cpu_seq_stop(struct seq_file *seq, void *v)
 442 {
 443 }
 444
 445 static const struct seq_operations cpu_seq_ops = {
 446         .start          = cpu_seq_start,
 447         .next           = cpu_seq_next,
 448         .stop           = cpu_seq_stop,
 449         .show           = cpu_seq_show,
 450 };
 451
 452 static int cpu_seq_open(struct inode *inode, struct file *file)
 453 {
 454         struct cpu_private *priv = inode->i_private;
 455         struct seq_file *seq;
 456         int err;
 457
 458         err = seq_open(file, &cpu_seq_ops);
 459         if (!err) {
 460                 seq = file->private_data;
 461                 seq->private = priv;
 462         }
 463
 464         return err;
 465 }
 466
 467 static int write_msr(struct cpu_private *priv, u64 val)
 468 {
 469         u32 low, high;
 470
 471         high = (val >> 32) & 0xffffffff;
 472         low = val & 0xffffffff;
 473
 474         if (!wrmsr_safe_on_cpu(priv->cpu, priv->reg, low, high))
 475                 return 0;
 476
 477         return -EPERM;
 478 }
 479
 480 static int write_cpu_register(struct cpu_private *priv, const char *buf)
 481 {
 482         int ret = -EPERM;
 483         u64 val;
 484
 485         ret = strict_strtoull(buf, 0, &val);
 486         if (ret < 0)
 487                 return ret;
 488
 489         /* Supporting only MSRs */
 490         if (priv->type < CPU_TSS_BIT)
 491                 return write_msr(priv, val);
 492
 493         return ret;
 494 }
 495
 496 static ssize_t cpu_write(struct file *file, const char __user *ubuf,
 497                              size_t count, loff_t *off)
 498 {
 499         struct seq_file *seq = file->private_data;
 500         struct cpu_private *priv = seq->private;
 501         char buf[19];
 502
 503         if ((priv == NULL) || (count >= sizeof(buf)))
 504                 return -EINVAL;
 505
 506         if (copy_from_user(&buf, ubuf, count))
 507                 return -EFAULT;
 508
 509         buf[count] = 0;
 510
 511         if ((cpu_base[priv->type].write) && (cpu_file[priv->file].write))
 512                 if (!write_cpu_register(priv, buf))
 513                         return count;
 514
 515         return -EACCES;
 516 }
 517
 518 static const struct file_operations cpu_fops = {
 519         .owner          = THIS_MODULE,
 520         .open           = cpu_seq_open,
 521         .read           = seq_read,
 522         .write          = cpu_write,
 523         .llseek         = seq_lseek,
 524         .release        = seq_release,
 525 };
 526
 527 static int cpu_create_file(unsigned cpu, unsigned type, unsigned reg,
 528                            unsigned file, struct dentry *dentry)
 529 {
 530         struct cpu_private *priv = NULL;
 531
 532         /* Already intialized */
 533         if (file == CPU_INDEX_BIT)
 534                 if (per_cpu(cpu_arr[type].init, cpu))
 535                         return 0;
 536
 537         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 538         if (priv == NULL)
 539                 return -ENOMEM;
 540
 541         priv->cpu = cpu;
 542         priv->type = type;
 543         priv->reg = reg;
 544         priv->file = file;
 545         mutex_lock(&cpu_debug_lock);
 546         per_cpu(priv_arr[type], cpu) = priv;
 547         per_cpu(cpu_priv_count, cpu)++;
 548         mutex_unlock(&cpu_debug_lock);
 549
 550         if (file)
 551                 debugfs_create_file(cpu_file[file].name, S_IRUGO,
 552                                     dentry, (void *)priv, &cpu_fops);
 553         else {
 554                 debugfs_create_file(cpu_base[type].name, S_IRUGO,
 555                                     per_cpu(cpu_arr[type].dentry, cpu),
 556                                     (void *)priv, &cpu_fops);
 557                 mutex_lock(&cpu_debug_lock);
 558                 per_cpu(cpu_arr[type].init, cpu) = 1;
 559                 mutex_unlock(&cpu_debug_lock);
 560         }
 561
 562         return 0;
 563 }
 564
 565 static int cpu_init_regfiles(unsigned cpu, unsigned int type, unsigned reg,
 566                              struct dentry *dentry)
 567 {
 568         unsigned file;
 569         int err = 0;
 570
 571         for (file = 0; file <  ARRAY_SIZE(cpu_file); file++) {
 572                 err = cpu_create_file(cpu, type, reg, file, dentry);
 573                 if (err)
 574                         return err;
 575         }
 576
 577         return err;
 578 }
 579
 580 static int cpu_init_msr(unsigned cpu, unsigned type, struct dentry *dentry)
 581 {
 582         struct dentry *cpu_dentry = NULL;
 583         unsigned reg, reg_min, reg_max;
 584         int i, err = 0;
 585         char reg_dir[12];
 586         u32 low, high;
 587
 588         for (i = 0; i < ARRAY_SIZE(cpu_reg_range); i++) {
 589                 if (!get_cpu_range(cpu, &reg_min, &reg_max, i,
 590                                    cpu_base[type].flag))
 591                         continue;
 592
 593                 for (reg = reg_min; reg <= reg_max; reg++) {
 594                         if (rdmsr_safe_on_cpu(cpu, reg, &low, &high))
 595                                 continue;
 596
 597                         sprintf(reg_dir, "0x%x", reg);
 598                         cpu_dentry = debugfs_create_dir(reg_dir, dentry);
 599                         err = cpu_init_regfiles(cpu, type, reg, cpu_dentry);
 600                         if (err)
 601                                 return err;
 602                 }
 603         }
 604
 605         return err;
 606 }
 607
 608 static int cpu_init_allreg(unsigned cpu, struct dentry *dentry)
 609 {
 610         struct dentry *cpu_dentry = NULL;
 611         unsigned type;
 612         int err = 0;
 613
 614         for (type = 0; type <  ARRAY_SIZE(cpu_base) - 1; type++) {
 615                 if (!is_typeflag_valid(cpu, cpu_base[type].flag))
 616                         continue;
 617                 cpu_dentry = debugfs_create_dir(cpu_base[type].name, dentry);
 618                 per_cpu(cpu_arr[type].dentry, cpu) = cpu_dentry;
 619
 620                 if (type < CPU_TSS_BIT)
 621                         err = cpu_init_msr(cpu, type, cpu_dentry);
 622                 else
 623                         err = cpu_create_file(cpu, type, 0, CPU_INDEX_BIT,
 624                                               cpu_dentry);
 625                 if (err)
 626                         return err;
 627         }
 628
 629         return err;
 630 }
 631
 632 static int cpu_init_cpu(void)
 633 {
 634         struct dentry *cpu_dentry = NULL;
 635         struct cpuinfo_x86 *cpui;
 636         char cpu_dir[12];
 637         unsigned cpu;
 638         int err = 0;
 639
 640         for (cpu = 0; cpu < nr_cpu_ids; cpu++) {
 641                 cpui = &cpu_data(cpu);
 642                 if (!cpu_has(cpui, X86_FEATURE_MSR))
 643                         continue;
 644
 645                 sprintf(cpu_dir, "cpu%d", cpu);
 646                 cpu_dentry = debugfs_create_dir(cpu_dir, cpu_debugfs_dir);
 647                 err = cpu_init_allreg(cpu, cpu_dentry);
 648
 649                 pr_info("cpu%d(%d) debug files %d\n",
 650                         cpu, nr_cpu_ids, per_cpu(cpu_priv_count, cpu));
 651                 if (per_cpu(cpu_priv_count, cpu) > MAX_CPU_FILES) {
 652                         pr_err("Register files count %d exceeds limit %d\n",
 653                                 per_cpu(cpu_priv_count, cpu), MAX_CPU_FILES);
 654                         per_cpu(cpu_priv_count, cpu) = MAX_CPU_FILES;
 655                         err = -ENFILE;
 656                 }
 657                 if (err)
 658                         return err;
 659         }
 660
 661         return err;
 662 }
 663
 664 static int __init cpu_debug_init(void)
 665 {
 666         cpu_debugfs_dir = debugfs_create_dir("cpu", arch_debugfs_dir);
 667
 668         return cpu_init_cpu();
 669 }
 670
 671 static void __exit cpu_debug_exit(void)
 672 {
 673         int i, cpu;
 674
 675         if (cpu_debugfs_dir)
 676                 debugfs_remove_recursive(cpu_debugfs_dir);
 677
 678         for (cpu = 0; cpu <  nr_cpu_ids; cpu++)
 679                 for (i = 0; i < per_cpu(cpu_priv_count, cpu); i++)
 680                         kfree(per_cpu(priv_arr[i], cpu));
 681 }
 682
 683 module_init(cpu_debug_init);
 684 module_exit(cpu_debug_exit);
 685
 686 MODULE_AUTHOR("Jaswinder Singh Rajput");
 687 MODULE_DESCRIPTION("CPU Debug module");
 688 MODULE_LICENSE("GPL");