kernel/trace/trace_kprobe.c

   1 /*
   2  * Kprobes-based tracing events
   3  *
   4  * Created by Masami Hiramatsu <mhiramat@redhat.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/uaccess.h>
  22 #include <linux/kprobes.h>
  23 #include <linux/seq_file.h>
  24 #include <linux/slab.h>
  25 #include <linux/smp.h>
  26 #include <linux/debugfs.h>
  27 #include <linux/types.h>
  28 #include <linux/string.h>
  29 #include <linux/ctype.h>
  30 #include <linux/ptrace.h>
  31 #include <linux/perf_event.h>
  32 #include <linux/stringify.h>
  33 #include <linux/limits.h>
  34 #include <asm/bitsperlong.h>
  35
  36 #include "trace.h"
  37 #include "trace_output.h"
  38
  39 #define MAX_TRACE_ARGS 128
  40 #define MAX_ARGSTR_LEN 63
  41 #define MAX_EVENT_NAME_LEN 64
  42 #define MAX_STRING_SIZE PATH_MAX
  43 #define KPROBE_EVENT_SYSTEM "kprobes"
  44
  45 /* Reserved field names */
  46 #define FIELD_STRING_IP "__probe_ip"
  47 #define FIELD_STRING_RETIP "__probe_ret_ip"
  48 #define FIELD_STRING_FUNC "__probe_func"
  49
  50 const char *reserved_field_names[] = {
  51         "common_type",
  52         "common_flags",
  53         "common_preempt_count",
  54         "common_pid",
  55         "common_tgid",
  56         FIELD_STRING_IP,
  57         FIELD_STRING_RETIP,
  58         FIELD_STRING_FUNC,
  59 };
  60
  61 /* Printing function type */
  62 typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *,
  63                                  void *);
  64 #define PRINT_TYPE_FUNC_NAME(type)      print_type_##type
  65 #define PRINT_TYPE_FMT_NAME(type)       print_type_format_##type
  66
  67 /* Printing  in basic type function template */
  68 #define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt, cast)                   \
  69 static __kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s,    \
  70                                                 const char *name,       \
  71                                                 void *data, void *ent)\
  72 {                                                                       \
  73         return trace_seq_printf(s, " %s=" fmt, name, (cast)*(type *)data);\
  74 }                                                                       \
  75 static const char PRINT_TYPE_FMT_NAME(type)[] = fmt;
  76
  77 DEFINE_BASIC_PRINT_TYPE_FUNC(u8, "%x", unsigned int)
  78 DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "%x", unsigned int)
  79 DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "%lx", unsigned long)
  80 DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "%llx", unsigned long long)
  81 DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d", int)
  82 DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d", int)
  83 DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%ld", long)
  84 DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%lld", long long)
  85
  86 /* data_rloc: data relative location, compatible with u32 */
  87 #define make_data_rloc(len, roffs)      \
  88         (((u32)(len) << 16) | ((u32)(roffs) & 0xffff))
  89 #define get_rloc_len(dl)        ((u32)(dl) >> 16)
  90 #define get_rloc_offs(dl)       ((u32)(dl) & 0xffff)
  91
  92 static inline void *get_rloc_data(u32 *dl)
  93 {
  94         return (u8 *)dl + get_rloc_offs(*dl);
  95 }
  96
  97 /* For data_loc conversion */
  98 static inline void *get_loc_data(u32 *dl, void *ent)
  99 {
 100         return (u8 *)ent + get_rloc_offs(*dl);
 101 }
 102
 103 /*
 104  * Convert data_rloc to data_loc:
 105  *  data_rloc stores the offset from data_rloc itself, but data_loc
 106  *  stores the offset from event entry.
 107  */
 108 #define convert_rloc_to_loc(dl, offs)   ((u32)(dl) + (offs))
 109
 110 /* For defining macros, define string/string_size types */
 111 typedef u32 string;
 112 typedef u32 string_size;
 113
 114 /* Print type function for string type */
 115 static __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s,
 116                                                   const char *name,
 117                                                   void *data, void *ent)
 118 {
 119         int len = *(u32 *)data >> 16;
 120
 121         if (!len)
 122                 return trace_seq_printf(s, " %s=(fault)", name);
 123         else
 124                 return trace_seq_printf(s, " %s=\"%s\"", name,
 125                                         (const char *)get_loc_data(data, ent));
 126 }
 127 static const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\"";
 128
 129 /* Data fetch function type */
 130 typedef void (*fetch_func_t)(struct pt_regs *, void *, void *);
 131
 132 struct fetch_param {
 133         fetch_func_t    fn;
 134         void *data;
 135 };
 136
 137 static __kprobes void call_fetch(struct fetch_param *fprm,
 138                                  struct pt_regs *regs, void *dest)
 139 {
 140         return fprm->fn(regs, fprm->data, dest);
 141 }
 142
 143 #define FETCH_FUNC_NAME(method, type)   fetch_##method##_##type
 144 /*
 145  * Define macro for basic types - we don't need to define s* types, because
 146  * we have to care only about bitwidth at recording time.
 147  */
 148 #define DEFINE_BASIC_FETCH_FUNCS(method) \
 149 DEFINE_FETCH_##method(u8)               \
 150 DEFINE_FETCH_##method(u16)              \
 151 DEFINE_FETCH_##method(u32)              \
 152 DEFINE_FETCH_##method(u64)
 153
 154 #define CHECK_FETCH_FUNCS(method, fn)                   \
 155         (((FETCH_FUNC_NAME(method, u8) == fn) ||        \
 156           (FETCH_FUNC_NAME(method, u16) == fn) ||       \
 157           (FETCH_FUNC_NAME(method, u32) == fn) ||       \
 158           (FETCH_FUNC_NAME(method, u64) == fn) ||       \
 159           (FETCH_FUNC_NAME(method, string) == fn) ||    \
 160           (FETCH_FUNC_NAME(method, string_size) == fn)) \
 161          && (fn != NULL))
 162
 163 /* Data fetch function templates */
 164 #define DEFINE_FETCH_reg(type)                                          \
 165 static __kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs,  \
 166                                         void *offset, void *dest)       \
 167 {                                                                       \
 168         *(type *)dest = (type)regs_get_register(regs,                   \
 169                                 (unsigned int)((unsigned long)offset)); \
 170 }
 171 DEFINE_BASIC_FETCH_FUNCS(reg)
 172 /* No string on the register */
 173 #define fetch_reg_string NULL
 174 #define fetch_reg_string_size NULL
 175
 176 #define DEFINE_FETCH_stack(type)                                        \
 177 static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\
 178                                           void *offset, void *dest)     \
 179 {                                                                       \
 180         *(type *)dest = (type)regs_get_kernel_stack_nth(regs,           \
 181                                 (unsigned int)((unsigned long)offset)); \
 182 }
 183 DEFINE_BASIC_FETCH_FUNCS(stack)
 184 /* No string on the stack entry */
 185 #define fetch_stack_string NULL
 186 #define fetch_stack_string_size NULL
 187
 188 #define DEFINE_FETCH_retval(type)                                       \
 189 static __kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs,\
 190                                           void *dummy, void *dest)      \
 191 {                                                                       \
 192         *(type *)dest = (type)regs_return_value(regs);                  \
 193 }
 194 DEFINE_BASIC_FETCH_FUNCS(retval)
 195 /* No string on the retval */
 196 #define fetch_retval_string NULL
 197 #define fetch_retval_string_size NULL
 198
 199 #define DEFINE_FETCH_memory(type)                                       \
 200 static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\
 201                                           void *addr, void *dest)       \
 202 {                                                                       \
 203         type retval;                                                    \
 204         if (probe_kernel_address(addr, retval))                         \
 205                 *(type *)dest = 0;                                      \
 206         else                                                            \
 207                 *(type *)dest = retval;                                 \
 208 }
 209 DEFINE_BASIC_FETCH_FUNCS(memory)
 210 /*
 211  * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
 212  * length and relative data location.
 213  */
 214 static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
 215                                                       void *addr, void *dest)
 216 {
 217         long ret;
 218         int maxlen = get_rloc_len(*(u32 *)dest);
 219         u8 *dst = get_rloc_data(dest);
 220         u8 *src = addr;
 221         mm_segment_t old_fs = get_fs();
 222         if (!maxlen)
 223                 return;
 224         /*
 225          * Try to get string again, since the string can be changed while
 226          * probing.
 227          */
 228         set_fs(KERNEL_DS);
 229         pagefault_disable();
 230         do
 231                 ret = __copy_from_user_inatomic(dst++, src++, 1);
 232         while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen);
 233         dst[-1] = '\0';
 234         pagefault_enable();
 235         set_fs(old_fs);
 236
 237         if (ret < 0) {  /* Failed to fetch string */
 238                 ((u8 *)get_rloc_data(dest))[0] = '\0';
 239                 *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest));
 240         } else
 241                 *(u32 *)dest = make_data_rloc(src - (u8 *)addr,
 242                                               get_rloc_offs(*(u32 *)dest));
 243 }
 244 /* Return the length of string -- including null terminal byte */
 245 static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
 246                                                         void *addr, void *dest)
 247 {
 248         int ret, len = 0;
 249         u8 c;
 250         mm_segment_t old_fs = get_fs();
 251
 252         set_fs(KERNEL_DS);
 253         pagefault_disable();
 254         do {
 255                 ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1);
 256                 len++;
 257         } while (c && ret == 0 && len < MAX_STRING_SIZE);
 258         pagefault_enable();
 259         set_fs(old_fs);
 260
 261         if (ret < 0)    /* Failed to check the length */
 262                 *(u32 *)dest = 0;
 263         else
 264                 *(u32 *)dest = len;
 265 }
 266
 267 /* Memory fetching by symbol */
 268 struct symbol_cache {
 269         char *symbol;
 270         long offset;
 271         unsigned long addr;
 272 };
 273
 274 static unsigned long update_symbol_cache(struct symbol_cache *sc)
 275 {
 276         sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol);
 277         if (sc->addr)
 278                 sc->addr += sc->offset;
 279         return sc->addr;
 280 }
 281
 282 static void free_symbol_cache(struct symbol_cache *sc)
 283 {
 284         kfree(sc->symbol);
 285         kfree(sc);
 286 }
 287
 288 static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset)
 289 {
 290         struct symbol_cache *sc;
 291
 292         if (!sym || strlen(sym) == 0)
 293                 return NULL;
 294         sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL);
 295         if (!sc)
 296                 return NULL;
 297
 298         sc->symbol = kstrdup(sym, GFP_KERNEL);
 299         if (!sc->symbol) {
 300                 kfree(sc);
 301                 return NULL;
 302         }
 303         sc->offset = offset;
 304
 305         update_symbol_cache(sc);
 306         return sc;
 307 }
 308
 309 #define DEFINE_FETCH_symbol(type)                                       \
 310 static __kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs,\
 311                                           void *data, void *dest)       \
 312 {                                                                       \
 313         struct symbol_cache *sc = data;                                 \
 314         if (sc->addr)                                                   \
 315                 fetch_memory_##type(regs, (void *)sc->addr, dest);      \
 316         else                                                            \
 317                 *(type *)dest = 0;                                      \
 318 }
 319 DEFINE_BASIC_FETCH_FUNCS(symbol)
 320 DEFINE_FETCH_symbol(string)
 321 DEFINE_FETCH_symbol(string_size)
 322
 323 /* Dereference memory access function */
 324 struct deref_fetch_param {
 325         struct fetch_param orig;
 326         long offset;
 327 };
 328
 329 #define DEFINE_FETCH_deref(type)                                        \
 330 static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\
 331                                             void *data, void *dest)     \
 332 {                                                                       \
 333         struct deref_fetch_param *dprm = data;                          \
 334         unsigned long addr;                                             \
 335         call_fetch(&dprm->orig, regs, &addr);                           \
 336         if (addr) {                                                     \
 337                 addr += dprm->offset;                                   \
 338                 fetch_memory_##type(regs, (void *)addr, dest);          \
 339         } else                                                          \
 340                 *(type *)dest = 0;                                      \
 341 }
 342 DEFINE_BASIC_FETCH_FUNCS(deref)
 343 DEFINE_FETCH_deref(string)
 344 DEFINE_FETCH_deref(string_size)
 345
 346 static __kprobes void free_deref_fetch_param(struct deref_fetch_param *data)
 347 {
 348         if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
 349                 free_deref_fetch_param(data->orig.data);
 350         else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
 351                 free_symbol_cache(data->orig.data);
 352         kfree(data);
 353 }
 354
 355 /* Bitfield fetch function */
 356 struct bitfield_fetch_param {
 357         struct fetch_param orig;
 358         unsigned char hi_shift;
 359         unsigned char low_shift;
 360 };
 361
 362 #define DEFINE_FETCH_bitfield(type)                                     \
 363 static __kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs,\
 364                                             void *data, void *dest)     \
 365 {                                                                       \
 366         struct bitfield_fetch_param *bprm = data;                       \
 367         type buf = 0;                                                   \
 368         call_fetch(&bprm->orig, regs, &buf);                            \
 369         if (buf) {                                                      \
 370                 buf <<= bprm->hi_shift;                                 \
 371                 buf >>= bprm->low_shift;                                \
 372         }                                                               \
 373         *(type *)dest = buf;                                            \
 374 }
 375 DEFINE_BASIC_FETCH_FUNCS(bitfield)
 376 #define fetch_bitfield_string NULL
 377 #define fetch_bitfield_string_size NULL
 378
 379 static __kprobes void
 380 free_bitfield_fetch_param(struct bitfield_fetch_param *data)
 381 {
 382         /*
 383          * Don't check the bitfield itself, because this must be the
 384          * last fetch function.
 385          */
 386         if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
 387                 free_deref_fetch_param(data->orig.data);
 388         else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
 389                 free_symbol_cache(data->orig.data);
 390         kfree(data);
 391 }
 392 /* Default (unsigned long) fetch type */
 393 #define __DEFAULT_FETCH_TYPE(t) u##t
 394 #define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
 395 #define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG)
 396 #define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE)
 397
 398 /* Fetch types */
 399 enum {
 400         FETCH_MTD_reg = 0,
 401         FETCH_MTD_stack,
 402         FETCH_MTD_retval,
 403         FETCH_MTD_memory,
 404         FETCH_MTD_symbol,
 405         FETCH_MTD_deref,
 406         FETCH_MTD_bitfield,
 407         FETCH_MTD_END,
 408 };
 409
 410 #define ASSIGN_FETCH_FUNC(method, type) \
 411         [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type)
 412
 413 #define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
 414         {.name = _name,                         \
 415          .size = _size,                                 \
 416          .is_signed = sign,                             \
 417          .print = PRINT_TYPE_FUNC_NAME(ptype),          \
 418          .fmt = PRINT_TYPE_FMT_NAME(ptype),             \
 419          .fmttype = _fmttype,                           \
 420          .fetch = {                                     \
 421 ASSIGN_FETCH_FUNC(reg, ftype),                          \
 422 ASSIGN_FETCH_FUNC(stack, ftype),                        \
 423 ASSIGN_FETCH_FUNC(retval, ftype),                       \
 424 ASSIGN_FETCH_FUNC(memory, ftype),                       \
 425 ASSIGN_FETCH_FUNC(symbol, ftype),                       \
 426 ASSIGN_FETCH_FUNC(deref, ftype),                        \
 427 ASSIGN_FETCH_FUNC(bitfield, ftype),                     \
 428           }                                             \
 429         }
 430
 431 #define ASSIGN_FETCH_TYPE(ptype, ftype, sign)                   \
 432         __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype)
 433
 434 #define FETCH_TYPE_STRING 0
 435 #define FETCH_TYPE_STRSIZE 1
 436
 437 /* Fetch type information table */
 438 static const struct fetch_type {
 439         const char      *name;          /* Name of type */
 440         size_t          size;           /* Byte size of type */
 441         int             is_signed;      /* Signed flag */
 442         print_type_func_t       print;  /* Print functions */
 443         const char      *fmt;           /* Fromat string */
 444         const char      *fmttype;       /* Name in format file */
 445         /* Fetch functions */
 446         fetch_func_t    fetch[FETCH_MTD_END];
 447 } fetch_type_table[] = {
 448         /* Special types */
 449         [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string,
 450                                         sizeof(u32), 1, "__data_loc char[]"),
 451         [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32,
 452                                         string_size, sizeof(u32), 0, "u32"),
 453         /* Basic types */
 454         ASSIGN_FETCH_TYPE(u8,  u8,  0),
 455         ASSIGN_FETCH_TYPE(u16, u16, 0),
 456         ASSIGN_FETCH_TYPE(u32, u32, 0),
 457         ASSIGN_FETCH_TYPE(u64, u64, 0),
 458         ASSIGN_FETCH_TYPE(s8,  u8,  1),
 459         ASSIGN_FETCH_TYPE(s16, u16, 1),
 460         ASSIGN_FETCH_TYPE(s32, u32, 1),
 461         ASSIGN_FETCH_TYPE(s64, u64, 1),
 462 };
 463
 464 static const struct fetch_type *find_fetch_type(const char *type)
 465 {
 466         int i;
 467
 468         if (!type)
 469                 type = DEFAULT_FETCH_TYPE_STR;
 470
 471         /* Special case: bitfield */
 472         if (*type == 'b') {
 473                 unsigned long bs;
 474                 type = strchr(type, '/');
 475                 if (!type)
 476                         goto fail;
 477                 type++;
 478                 if (strict_strtoul(type, 0, &bs))
 479                         goto fail;
 480                 switch (bs) {
 481                 case 8:
 482                         return find_fetch_type("u8");
 483                 case 16:
 484                         return find_fetch_type("u16");
 485                 case 32:
 486                         return find_fetch_type("u32");
 487                 case 64:
 488                         return find_fetch_type("u64");
 489                 default:
 490                         goto fail;
 491                 }
 492         }
 493
 494         for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++)
 495                 if (strcmp(type, fetch_type_table[i].name) == 0)
 496                         return &fetch_type_table[i];
 497 fail:
 498         return NULL;
 499 }
 500
 501 /* Special function : only accept unsigned long */
 502 static __kprobes void fetch_stack_address(struct pt_regs *regs,
 503                                           void *dummy, void *dest)
 504 {
 505         *(unsigned long *)dest = kernel_stack_pointer(regs);
 506 }
 507
 508 static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
 509                                             fetch_func_t orig_fn)
 510 {
 511         int i;
 512
 513         if (type != &fetch_type_table[FETCH_TYPE_STRING])
 514                 return NULL;    /* Only string type needs size function */
 515         for (i = 0; i < FETCH_MTD_END; i++)
 516                 if (type->fetch[i] == orig_fn)
 517                         return fetch_type_table[FETCH_TYPE_STRSIZE].fetch[i];
 518
 519         WARN_ON(1);     /* This should not happen */
 520         return NULL;
 521 }
 522
 523 /**
 524  * Kprobe event core functions
 525  */
 526
 527 struct probe_arg {
 528         struct fetch_param      fetch;
 529         struct fetch_param      fetch_size;
 530         unsigned int            offset; /* Offset from argument entry */
 531         const char              *name;  /* Name of this argument */
 532         const char              *comm;  /* Command of this argument */
 533         const struct fetch_type *type;  /* Type of this argument */
 534 };
 535
 536 /* Flags for trace_probe */
 537 #define TP_FLAG_TRACE   1
 538 #define TP_FLAG_PROFILE 2
 539
 540 struct trace_probe {
 541         struct list_head        list;
 542         struct kretprobe        rp;     /* Use rp.kp for kprobe use */
 543         unsigned long           nhit;
 544         unsigned int            flags;  /* For TP_FLAG_* */
 545         const char              *symbol;        /* symbol name */
 546         struct ftrace_event_class       class;
 547         struct ftrace_event_call        call;
 548         ssize_t                 size;           /* trace entry size */
 549         unsigned int            nr_args;
 550         struct probe_arg        args[];
 551 };
 552
 553 #define SIZEOF_TRACE_PROBE(n)                   \
 554         (offsetof(struct trace_probe, args) +   \
 555         (sizeof(struct probe_arg) * (n)))
 556
 557
 558 static __kprobes int probe_is_return(struct trace_probe *tp)
 559 {
 560         return tp->rp.handler != NULL;
 561 }
 562
 563 static __kprobes const char *probe_symbol(struct trace_probe *tp)
 564 {
 565         return tp->symbol ? tp->symbol : "unknown";
 566 }
 567
 568 static int register_probe_event(struct trace_probe *tp);
 569 static void unregister_probe_event(struct trace_probe *tp);
 570
 571 static DEFINE_MUTEX(probe_lock);
 572 static LIST_HEAD(probe_list);
 573
 574 static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs);
 575 static int kretprobe_dispatcher(struct kretprobe_instance *ri,
 576                                 struct pt_regs *regs);
 577
 578 /* Check the name is good for event/group/fields */
 579 static int is_good_name(const char *name)
 580 {
 581         if (!isalpha(*name) && *name != '_')
 582                 return 0;
 583         while (*++name != '\0') {
 584                 if (!isalpha(*name) && !isdigit(*name) && *name != '_')
 585                         return 0;
 586         }
 587         return 1;
 588 }
 589
 590 /*
 591  * Allocate new trace_probe and initialize it (including kprobes).
 592  */
 593 static struct trace_probe *alloc_trace_probe(const char *group,
 594                                              const char *event,
 595                                              void *addr,
 596                                              const char *symbol,
 597                                              unsigned long offs,
 598                                              int nargs, int is_return)
 599 {
 600         struct trace_probe *tp;
 601         int ret = -ENOMEM;
 602
 603         tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL);
 604         if (!tp)
 605                 return ERR_PTR(ret);
 606
 607         if (symbol) {
 608                 tp->symbol = kstrdup(symbol, GFP_KERNEL);
 609                 if (!tp->symbol)
 610                         goto error;
 611                 tp->rp.kp.symbol_name = tp->symbol;
 612                 tp->rp.kp.offset = offs;
 613         } else
 614                 tp->rp.kp.addr = addr;
 615
 616         if (is_return)
 617                 tp->rp.handler = kretprobe_dispatcher;
 618         else
 619                 tp->rp.kp.pre_handler = kprobe_dispatcher;
 620
 621         if (!event || !is_good_name(event)) {
 622                 ret = -EINVAL;
 623                 goto error;
 624         }
 625
 626         tp->call.class = &tp->class;
 627         tp->call.name = kstrdup(event, GFP_KERNEL);
 628         if (!tp->call.name)
 629                 goto error;
 630
 631         if (!group || !is_good_name(group)) {
 632                 ret = -EINVAL;
 633                 goto error;
 634         }
 635
 636         tp->class.system = kstrdup(group, GFP_KERNEL);
 637         if (!tp->class.system)
 638                 goto error;
 639
 640         INIT_LIST_HEAD(&tp->list);
 641         return tp;
 642 error:
 643         kfree(tp->call.name);
 644         kfree(tp->symbol);
 645         kfree(tp);
 646         return ERR_PTR(ret);
 647 }
 648
 649 static void free_probe_arg(struct probe_arg *arg)
 650 {
 651         if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn))
 652                 free_bitfield_fetch_param(arg->fetch.data);
 653         else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
 654                 free_deref_fetch_param(arg->fetch.data);
 655         else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
 656                 free_symbol_cache(arg->fetch.data);
 657         kfree(arg->name);
 658         kfree(arg->comm);
 659 }
 660
 661 static void free_trace_probe(struct trace_probe *tp)
 662 {
 663         int i;
 664
 665         for (i = 0; i < tp->nr_args; i++)
 666                 free_probe_arg(&tp->args[i]);
 667
 668         kfree(tp->call.class->system);
 669         kfree(tp->call.name);
 670         kfree(tp->symbol);
 671         kfree(tp);
 672 }
 673
 674 static struct trace_probe *find_probe_event(const char *event,
 675                                             const char *group)
 676 {
 677         struct trace_probe *tp;
 678
 679         list_for_each_entry(tp, &probe_list, list)
 680                 if (strcmp(tp->call.name, event) == 0 &&
 681                     strcmp(tp->call.class->system, group) == 0)
 682                         return tp;
 683         return NULL;
 684 }
 685
 686 /* Unregister a trace_probe and probe_event: call with locking probe_lock */
 687 static void unregister_trace_probe(struct trace_probe *tp)
 688 {
 689         if (probe_is_return(tp))
 690                 unregister_kretprobe(&tp->rp);
 691         else
 692                 unregister_kprobe(&tp->rp.kp);
 693         list_del(&tp->list);
 694         unregister_probe_event(tp);
 695 }
 696
 697 /* Register a trace_probe and probe_event */
 698 static int register_trace_probe(struct trace_probe *tp)
 699 {
 700         struct trace_probe *old_tp;
 701         int ret;
 702
 703         mutex_lock(&probe_lock);
 704
 705         /* register as an event */
 706         old_tp = find_probe_event(tp->call.name, tp->call.class->system);
 707         if (old_tp) {
 708                 /* delete old event */
 709                 unregister_trace_probe(old_tp);
 710                 free_trace_probe(old_tp);
 711         }
 712         ret = register_probe_event(tp);
 713         if (ret) {
 714                 pr_warning("Failed to register probe event(%d)\n", ret);
 715                 goto end;
 716         }
 717
 718         tp->rp.kp.flags |= KPROBE_FLAG_DISABLED;
 719         if (probe_is_return(tp))
 720                 ret = register_kretprobe(&tp->rp);
 721         else
 722                 ret = register_kprobe(&tp->rp.kp);
 723
 724         if (ret) {
 725                 pr_warning("Could not insert probe(%d)\n", ret);
 726                 if (ret == -EILSEQ) {
 727                         pr_warning("Probing address(0x%p) is not an "
 728                                    "instruction boundary.\n",
 729                                    tp->rp.kp.addr);
 730                         ret = -EINVAL;
 731                 }
 732                 unregister_probe_event(tp);
 733         } else
 734                 list_add_tail(&tp->list, &probe_list);
 735 end:
 736         mutex_unlock(&probe_lock);
 737         return ret;
 738 }
 739
 740 /* Split symbol and offset. */
 741 static int split_symbol_offset(char *symbol, unsigned long *offset)
 742 {
 743         char *tmp;
 744         int ret;
 745
 746         if (!offset)
 747                 return -EINVAL;
 748
 749         tmp = strchr(symbol, '+');
 750         if (tmp) {
 751                 /* skip sign because strict_strtol doesn't accept '+' */
 752                 ret = strict_strtoul(tmp + 1, 0, offset);
 753                 if (ret)
 754                         return ret;
 755                 *tmp = '\0';
 756         } else
 757                 *offset = 0;
 758         return 0;
 759 }
 760
 761 #define PARAM_MAX_ARGS 16
 762 #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
 763
 764 static int parse_probe_vars(char *arg, const struct fetch_type *t,
 765                             struct fetch_param *f, int is_return)
 766 {
 767         int ret = 0;
 768         unsigned long param;
 769
 770         if (strcmp(arg, "retval") == 0) {
 771                 if (is_return)
 772                         f->fn = t->fetch[FETCH_MTD_retval];
 773                 else
 774                         ret = -EINVAL;
 775         } else if (strncmp(arg, "stack", 5) == 0) {
 776                 if (arg[5] == '\0') {
 777                         if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0)
 778                                 f->fn = fetch_stack_address;
 779                         else
 780                                 ret = -EINVAL;
 781                 } else if (isdigit(arg[5])) {
 782                         ret = strict_strtoul(arg + 5, 10, &param);
 783                         if (ret || param > PARAM_MAX_STACK)
 784                                 ret = -EINVAL;
 785                         else {
 786                                 f->fn = t->fetch[FETCH_MTD_stack];
 787                                 f->data = (void *)param;
 788                         }
 789                 } else
 790                         ret = -EINVAL;
 791         } else
 792                 ret = -EINVAL;
 793         return ret;
 794 }
 795
 796 /* Recursive argument parser */
 797 static int __parse_probe_arg(char *arg, const struct fetch_type *t,
 798                              struct fetch_param *f, int is_return)
 799 {
 800         int ret = 0;
 801         unsigned long param;
 802         long offset;
 803         char *tmp;
 804
 805         switch (arg[0]) {
 806         case '$':
 807                 ret = parse_probe_vars(arg + 1, t, f, is_return);
 808                 break;
 809         case '%':       /* named register */
 810                 ret = regs_query_register_offset(arg + 1);
 811                 if (ret >= 0) {
 812                         f->fn = t->fetch[FETCH_MTD_reg];
 813                         f->data = (void *)(unsigned long)ret;
 814                         ret = 0;
 815                 }
 816                 break;
 817         case '@':       /* memory or symbol */
 818                 if (isdigit(arg[1])) {
 819                         ret = strict_strtoul(arg + 1, 0, &param);
 820                         if (ret)
 821                                 break;
 822                         f->fn = t->fetch[FETCH_MTD_memory];
 823                         f->data = (void *)param;
 824                 } else {
 825                         ret = split_symbol_offset(arg + 1, &offset);
 826                         if (ret)
 827                                 break;
 828                         f->data = alloc_symbol_cache(arg + 1, offset);
 829                         if (f->data)
 830                                 f->fn = t->fetch[FETCH_MTD_symbol];
 831                 }
 832                 break;
 833         case '+':       /* deref memory */
 834                 arg++;  /* Skip '+', because strict_strtol() rejects it. */
 835         case '-':
 836                 tmp = strchr(arg, '(');
 837                 if (!tmp)
 838                         break;
 839                 *tmp = '\0';
 840                 ret = strict_strtol(arg, 0, &offset);
 841                 if (ret)
 842                         break;
 843                 arg = tmp + 1;
 844                 tmp = strrchr(arg, ')');
 845                 if (tmp) {
 846                         struct deref_fetch_param *dprm;
 847                         const struct fetch_type *t2 = find_fetch_type(NULL);
 848                         *tmp = '\0';
 849                         dprm = kzalloc(sizeof(struct deref_fetch_param),
 850                                        GFP_KERNEL);
 851                         if (!dprm)
 852                                 return -ENOMEM;
 853                         dprm->offset = offset;
 854                         ret = __parse_probe_arg(arg, t2, &dprm->orig,
 855                                                 is_return);
 856                         if (ret)
 857                                 kfree(dprm);
 858                         else {
 859                                 f->fn = t->fetch[FETCH_MTD_deref];
 860                                 f->data = (void *)dprm;
 861                         }
 862                 }
 863                 break;
 864         }
 865         if (!ret && !f->fn) {   /* Parsed, but do not find fetch method */
 866                 pr_info("%s type has no corresponding fetch method.\n",
 867                         t->name);
 868                 ret = -EINVAL;
 869         }
 870         return ret;
 871 }
 872
 873 #define BYTES_TO_BITS(nb)       ((BITS_PER_LONG * (nb)) / sizeof(long))
 874
 875 /* Bitfield type needs to be parsed into a fetch function */
 876 static int __parse_bitfield_probe_arg(const char *bf,
 877                                       const struct fetch_type *t,
 878                                       struct fetch_param *f)
 879 {
 880         struct bitfield_fetch_param *bprm;
 881         unsigned long bw, bo;
 882         char *tail;
 883
 884         if (*bf != 'b')
 885                 return 0;
 886
 887         bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
 888         if (!bprm)
 889                 return -ENOMEM;
 890         bprm->orig = *f;
 891         f->fn = t->fetch[FETCH_MTD_bitfield];
 892         f->data = (void *)bprm;
 893
 894         bw = simple_strtoul(bf + 1, &tail, 0);  /* Use simple one */
 895         if (bw == 0 || *tail != '@')
 896                 return -EINVAL;
 897
 898         bf = tail + 1;
 899         bo = simple_strtoul(bf, &tail, 0);
 900         if (tail == bf || *tail != '/')
 901                 return -EINVAL;
 902
 903         bprm->hi_shift = BYTES_TO_BITS(t->size) - (bw + bo);
 904         bprm->low_shift = bprm->hi_shift + bo;
 905         return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0;
 906 }
 907
 908 /* String length checking wrapper */
 909 static int parse_probe_arg(char *arg, struct trace_probe *tp,
 910                            struct probe_arg *parg, int is_return)
 911 {
 912         const char *t;
 913         int ret;
 914
 915         if (strlen(arg) > MAX_ARGSTR_LEN) {
 916                 pr_info("Argument is too long.: %s\n",  arg);
 917                 return -ENOSPC;
 918         }
 919         parg->comm = kstrdup(arg, GFP_KERNEL);
 920         if (!parg->comm) {
 921                 pr_info("Failed to allocate memory for command '%s'.\n", arg);
 922                 return -ENOMEM;
 923         }
 924         t = strchr(parg->comm, ':');
 925         if (t) {
 926                 arg[t - parg->comm] = '\0';
 927                 t++;
 928         }
 929         parg->type = find_fetch_type(t);
 930         if (!parg->type) {
 931                 pr_info("Unsupported type: %s\n", t);
 932                 return -EINVAL;
 933         }
 934         parg->offset = tp->size;
 935         tp->size += parg->type->size;
 936         ret = __parse_probe_arg(arg, parg->type, &parg->fetch, is_return);
 937         if (ret >= 0 && t != NULL)
 938                 ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch);
 939         if (ret >= 0) {
 940                 parg->fetch_size.fn = get_fetch_size_function(parg->type,
 941                                                               parg->fetch.fn);
 942                 parg->fetch_size.data = parg->fetch.data;
 943         }
 944         return ret;
 945 }
 946
 947 /* Return 1 if name is reserved or already used by another argument */
 948 static int conflict_field_name(const char *name,
 949                                struct probe_arg *args, int narg)
 950 {
 951         int i;
 952         for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++)
 953                 if (strcmp(reserved_field_names[i], name) == 0)
 954                         return 1;
 955         for (i = 0; i < narg; i++)
 956                 if (strcmp(args[i].name, name) == 0)
 957                         return 1;
 958         return 0;
 959 }
 960
 961 static int create_trace_probe(int argc, char **argv)
 962 {
 963         /*
 964          * Argument syntax:
 965          *  - Add kprobe: p[:[GRP/]EVENT] KSYM[+OFFS]|KADDR [FETCHARGS]
 966          *  - Add kretprobe: r[:[GRP/]EVENT] KSYM[+0] [FETCHARGS]
 967          * Fetch args:
 968          *  $retval     : fetch return value
 969          *  $stack      : fetch stack address
 970          *  $stackN     : fetch Nth of stack (N:0-)
 971          *  @ADDR       : fetch memory at ADDR (ADDR should be in kernel)
 972          *  @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol)
 973          *  %REG        : fetch register REG
 974          * Dereferencing memory fetch:
 975          *  +|-offs(ARG) : fetch memory at ARG +|- offs address.
 976          * Alias name of args:
 977          *  NAME=FETCHARG : set NAME as alias of FETCHARG.
 978          * Type of args:
 979          *  FETCHARG:TYPE : use TYPE instead of unsigned long.
 980          */
 981         struct trace_probe *tp;
 982         int i, ret = 0;
 983         int is_return = 0, is_delete = 0;
 984         char *symbol = NULL, *event = NULL, *group = NULL;
 985         char *arg;
 986         unsigned long offset = 0;
 987         void *addr = NULL;
 988         char buf[MAX_EVENT_NAME_LEN];
 989
 990         /* argc must be >= 1 */
 991         if (argv[0][0] == 'p')
 992                 is_return = 0;
 993         else if (argv[0][0] == 'r')
 994                 is_return = 1;
 995         else if (argv[0][0] == '-')
 996                 is_delete = 1;
 997         else {
 998                 pr_info("Probe definition must be started with 'p', 'r' or"
 999                         " '-'.\n");
1000                 return -EINVAL;
1001         }
1002
1003         if (argv[0][1] == ':') {
1004                 event = &argv[0][2];
1005                 if (strchr(event, '/')) {
1006                         group = event;
1007                         event = strchr(group, '/') + 1;
1008                         event[-1] = '\0';
1009                         if (strlen(group) == 0) {
1010                                 pr_info("Group name is not specified\n");
1011                                 return -EINVAL;
1012                         }
1013                 }
1014                 if (strlen(event) == 0) {
1015                         pr_info("Event name is not specified\n");
1016                         return -EINVAL;
1017                 }
1018         }
1019         if (!group)
1020                 group = KPROBE_EVENT_SYSTEM;
1021
1022         if (is_delete) {
1023                 if (!event) {
1024                         pr_info("Delete command needs an event name.\n");
1025                         return -EINVAL;
1026                 }
1027                 mutex_lock(&probe_lock);
1028                 tp = find_probe_event(event, group);
1029                 if (!tp) {
1030                         mutex_unlock(&probe_lock);
1031                         pr_info("Event %s/%s doesn't exist.\n", group, event);
1032                         return -ENOENT;
1033                 }
1034                 /* delete an event */
1035                 unregister_trace_probe(tp);
1036                 free_trace_probe(tp);
1037                 mutex_unlock(&probe_lock);
1038                 return 0;
1039         }
1040
1041         if (argc < 2) {
1042                 pr_info("Probe point is not specified.\n");
1043                 return -EINVAL;
1044         }
1045         if (isdigit(argv[1][0])) {
1046                 if (is_return) {
1047                         pr_info("Return probe point must be a symbol.\n");
1048                         return -EINVAL;
1049                 }
1050                 /* an address specified */
1051                 ret = strict_strtoul(&argv[1][0], 0, (unsigned long *)&addr);
1052                 if (ret) {
1053                         pr_info("Failed to parse address.\n");
1054                         return ret;
1055                 }
1056         } else {
1057                 /* a symbol specified */
1058                 symbol = argv[1];
1059                 /* TODO: support .init module functions */
1060                 ret = split_symbol_offset(symbol, &offset);
1061                 if (ret) {
1062                         pr_info("Failed to parse symbol.\n");
1063                         return ret;
1064                 }
1065                 if (offset && is_return) {
1066                         pr_info("Return probe must be used without offset.\n");
1067                         return -EINVAL;
1068                 }
1069         }
1070         argc -= 2; argv += 2;
1071
1072         /* setup a probe */
1073         if (!event) {
1074                 /* Make a new event name */
1075                 if (symbol)
1076                         snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld",
1077                                  is_return ? 'r' : 'p', symbol, offset);
1078                 else
1079                         snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p",
1080                                  is_return ? 'r' : 'p', addr);
1081                 event = buf;
1082         }
1083         tp = alloc_trace_probe(group, event, addr, symbol, offset, argc,
1084                                is_return);
1085         if (IS_ERR(tp)) {
1086                 pr_info("Failed to allocate trace_probe.(%d)\n",
1087                         (int)PTR_ERR(tp));
1088                 return PTR_ERR(tp);
1089         }
1090
1091         /* parse arguments */
1092         ret = 0;
1093         for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
1094                 /* Increment count for freeing args in error case */
1095                 tp->nr_args++;
1096
1097                 /* Parse argument name */
1098                 arg = strchr(argv[i], '=');
1099                 if (arg) {
1100                         *arg++ = '\0';
1101                         tp->args[i].name = kstrdup(argv[i], GFP_KERNEL);
1102                 } else {
1103                         arg = argv[i];
1104                         /* If argument name is omitted, set "argN" */
1105                         snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1);
1106                         tp->args[i].name = kstrdup(buf, GFP_KERNEL);
1107                 }
1108
1109                 if (!tp->args[i].name) {
1110                         pr_info("Failed to allocate argument[%d] name.\n", i);
1111                         ret = -ENOMEM;
1112                         goto error;
1113                 }
1114
1115                 if (!is_good_name(tp->args[i].name)) {
1116                         pr_info("Invalid argument[%d] name: %s\n",
1117                                 i, tp->args[i].name);
1118                         ret = -EINVAL;
1119                         goto error;
1120                 }
1121
1122                 if (conflict_field_name(tp->args[i].name, tp->args, i)) {
1123                         pr_info("Argument[%d] name '%s' conflicts with "
1124                                 "another field.\n", i, argv[i]);
1125                         ret = -EINVAL;
1126                         goto error;
1127                 }
1128
1129                 /* Parse fetch argument */
1130                 ret = parse_probe_arg(arg, tp, &tp->args[i], is_return);
1131                 if (ret) {
1132                         pr_info("Parse error at argument[%d]. (%d)\n", i, ret);
1133                         goto error;
1134                 }
1135         }
1136
1137         ret = register_trace_probe(tp);
1138         if (ret)
1139                 goto error;
1140         return 0;
1141
1142 error:
1143         free_trace_probe(tp);
1144         return ret;
1145 }
1146
1147 static void cleanup_all_probes(void)
1148 {
1149         struct trace_probe *tp;
1150
1151         mutex_lock(&probe_lock);
1152         /* TODO: Use batch unregistration */
1153         while (!list_empty(&probe_list)) {
1154                 tp = list_entry(probe_list.next, struct trace_probe, list);
1155                 unregister_trace_probe(tp);
1156                 free_trace_probe(tp);
1157         }
1158         mutex_unlock(&probe_lock);
1159 }
1160
1161
1162 /* Probes listing interfaces */
1163 static void *probes_seq_start(struct seq_file *m, loff_t *pos)
1164 {
1165         mutex_lock(&probe_lock);
1166         return seq_list_start(&probe_list, *pos);
1167 }
1168
1169 static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos)
1170 {
1171         return seq_list_next(v, &probe_list, pos);
1172 }
1173
1174 static void probes_seq_stop(struct seq_file *m, void *v)
1175 {
1176         mutex_unlock(&probe_lock);
1177 }
1178
1179 static int probes_seq_show(struct seq_file *m, void *v)
1180 {
1181         struct trace_probe *tp = v;
1182         int i;
1183
1184         seq_printf(m, "%c", probe_is_return(tp) ? 'r' : 'p');
1185         seq_printf(m, ":%s/%s", tp->call.class->system, tp->call.name);
1186
1187         if (!tp->symbol)
1188                 seq_printf(m, " 0x%p", tp->rp.kp.addr);
1189         else if (tp->rp.kp.offset)
1190                 seq_printf(m, " %s+%u", probe_symbol(tp), tp->rp.kp.offset);
1191         else
1192                 seq_printf(m, " %s", probe_symbol(tp));
1193
1194         for (i = 0; i < tp->nr_args; i++)
1195                 seq_printf(m, " %s=%s", tp->args[i].name, tp->args[i].comm);
1196         seq_printf(m, "\n");
1197
1198         return 0;
1199 }
1200
1201 static const struct seq_operations probes_seq_op = {
1202         .start  = probes_seq_start,
1203         .next   = probes_seq_next,
1204         .stop   = probes_seq_stop,
1205         .show   = probes_seq_show
1206 };
1207
1208 static int probes_open(struct inode *inode, struct file *file)
1209 {
1210         if ((file->f_mode & FMODE_WRITE) &&
1211             (file->f_flags & O_TRUNC))
1212                 cleanup_all_probes();
1213
1214         return seq_open(file, &probes_seq_op);
1215 }
1216
1217 static int command_trace_probe(const char *buf)
1218 {
1219         char **argv;
1220         int argc = 0, ret = 0;
1221
1222         argv = argv_split(GFP_KERNEL, buf, &argc);
1223         if (!argv)
1224                 return -ENOMEM;
1225
1226         if (argc)
1227                 ret = create_trace_probe(argc, argv);
1228
1229         argv_free(argv);
1230         return ret;
1231 }
1232
1233 #define WRITE_BUFSIZE 4096
1234
1235 static ssize_t probes_write(struct file *file, const char __user *buffer,
1236                             size_t count, loff_t *ppos)
1237 {
1238         char *kbuf, *tmp;
1239         int ret;
1240         size_t done;
1241         size_t size;
1242
1243         kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL);
1244         if (!kbuf)
1245                 return -ENOMEM;
1246
1247         ret = done = 0;
1248         while (done < count) {
1249                 size = count - done;
1250                 if (size >= WRITE_BUFSIZE)
1251                         size = WRITE_BUFSIZE - 1;
1252                 if (copy_from_user(kbuf, buffer + done, size)) {
1253                         ret = -EFAULT;
1254                         goto out;
1255                 }
1256                 kbuf[size] = '\0';
1257                 tmp = strchr(kbuf, '\n');
1258                 if (tmp) {
1259                         *tmp = '\0';
1260                         size = tmp - kbuf + 1;
1261                 } else if (done + size < count) {
1262                         pr_warning("Line length is too long: "
1263                                    "Should be less than %d.", WRITE_BUFSIZE);
1264                         ret = -EINVAL;
1265                         goto out;
1266                 }
1267                 done += size;
1268                 /* Remove comments */
1269                 tmp = strchr(kbuf, '#');
1270                 if (tmp)
1271                         *tmp = '\0';
1272
1273                 ret = command_trace_probe(kbuf);
1274                 if (ret)
1275                         goto out;
1276         }
1277         ret = done;
1278 out:
1279         kfree(kbuf);
1280         return ret;
1281 }
1282
1283 static const struct file_operations kprobe_events_ops = {
1284         .owner          = THIS_MODULE,
1285         .open           = probes_open,
1286         .read           = seq_read,
1287         .llseek         = seq_lseek,
1288         .release        = seq_release,
1289         .write          = probes_write,
1290 };
1291
1292 /* Probes profiling interfaces */
1293 static int probes_profile_seq_show(struct seq_file *m, void *v)
1294 {
1295         struct trace_probe *tp = v;
1296
1297         seq_printf(m, "  %-44s %15lu %15lu\n", tp->call.name, tp->nhit,
1298                    tp->rp.kp.nmissed);
1299
1300         return 0;
1301 }
1302
1303 static const struct seq_operations profile_seq_op = {
1304         .start  = probes_seq_start,
1305         .next   = probes_seq_next,
1306         .stop   = probes_seq_stop,
1307         .show   = probes_profile_seq_show
1308 };
1309
1310 static int profile_open(struct inode *inode, struct file *file)
1311 {
1312         return seq_open(file, &profile_seq_op);
1313 }
1314
1315 static const struct file_operations kprobe_profile_ops = {
1316         .owner          = THIS_MODULE,
1317         .open           = profile_open,
1318         .read           = seq_read,
1319         .llseek         = seq_lseek,
1320         .release        = seq_release,
1321 };
1322
1323 /* Sum up total data length for dynamic arraies (strings) */
1324 static __kprobes int __get_data_size(struct trace_probe *tp,
1325                                      struct pt_regs *regs)
1326 {
1327         int i, ret = 0;
1328         u32 len;
1329
1330         for (i = 0; i < tp->nr_args; i++)
1331                 if (unlikely(tp->args[i].fetch_size.fn)) {
1332                         call_fetch(&tp->args[i].fetch_size, regs, &len);
1333                         ret += len;
1334                 }
1335
1336         return ret;
1337 }
1338
1339 /* Store the value of each argument */
1340 static __kprobes void store_trace_args(int ent_size, struct trace_probe *tp,
1341                                        struct pt_regs *regs,
1342                                        u8 *data, int maxlen)
1343 {
1344         int i;
1345         u32 end = tp->size;
1346         u32 *dl;        /* Data (relative) location */
1347
1348         for (i = 0; i < tp->nr_args; i++) {
1349                 if (unlikely(tp->args[i].fetch_size.fn)) {
1350                         /*
1351                          * First, we set the relative location and
1352                          * maximum data length to *dl
1353                          */
1354                         dl = (u32 *)(data + tp->args[i].offset);
1355                         *dl = make_data_rloc(maxlen, end - tp->args[i].offset);
1356                         /* Then try to fetch string or dynamic array data */
1357                         call_fetch(&tp->args[i].fetch, regs, dl);
1358                         /* Reduce maximum length */
1359                         end += get_rloc_len(*dl);
1360                         maxlen -= get_rloc_len(*dl);
1361                         /* Trick here, convert data_rloc to data_loc */
1362                         *dl = convert_rloc_to_loc(*dl,
1363                                  ent_size + tp->args[i].offset);
1364                 } else
1365                         /* Just fetching data normally */
1366                         call_fetch(&tp->args[i].fetch, regs,
1367                                    data + tp->args[i].offset);
1368         }
1369 }
1370
1371 /* Kprobe handler */
1372 static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
1373 {
1374         struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
1375         struct kprobe_trace_entry_head *entry;
1376         struct ring_buffer_event *event;
1377         struct ring_buffer *buffer;
1378         int size, dsize, pc;
1379         unsigned long irq_flags;
1380         struct ftrace_event_call *call = &tp->call;
1381
1382         tp->nhit++;
1383
1384         local_save_flags(irq_flags);
1385         pc = preempt_count();
1386
1387         dsize = __get_data_size(tp, regs);
1388         size = sizeof(*entry) + tp->size + dsize;
1389
1390         event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
1391                                                   size, irq_flags, pc);
1392         if (!event)
1393                 return;
1394
1395         entry = ring_buffer_event_data(event);
1396         entry->ip = (unsigned long)kp->addr;
1397         store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
1398
1399         if (!filter_current_check_discard(buffer, call, entry, event))
1400                 trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc);
1401 }
1402
1403 /* Kretprobe handler */
1404 static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
1405                                           struct pt_regs *regs)
1406 {
1407         struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
1408         struct kretprobe_trace_entry_head *entry;
1409         struct ring_buffer_event *event;
1410         struct ring_buffer *buffer;
1411         int size, pc, dsize;
1412         unsigned long irq_flags;
1413         struct ftrace_event_call *call = &tp->call;
1414
1415         local_save_flags(irq_flags);
1416         pc = preempt_count();
1417
1418         dsize = __get_data_size(tp, regs);
1419         size = sizeof(*entry) + tp->size + dsize;
1420
1421         event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
1422                                                   size, irq_flags, pc);
1423         if (!event)
1424                 return;
1425
1426         entry = ring_buffer_event_data(event);
1427         entry->func = (unsigned long)tp->rp.kp.addr;
1428         entry->ret_ip = (unsigned long)ri->ret_addr;
1429         store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
1430
1431         if (!filter_current_check_discard(buffer, call, entry, event))
1432                 trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc);
1433 }
1434
1435 /* Event entry printers */
1436 enum print_line_t
1437 print_kprobe_event(struct trace_iterator *iter, int flags,
1438                    struct trace_event *event)
1439 {
1440         struct kprobe_trace_entry_head *field;
1441         struct trace_seq *s = &iter->seq;
1442         struct trace_probe *tp;
1443         u8 *data;
1444         int i;
1445
1446         field = (struct kprobe_trace_entry_head *)iter->ent;
1447         tp = container_of(event, struct trace_probe, call.event);
1448
1449         if (!trace_seq_printf(s, "%s: (", tp->call.name))
1450                 goto partial;
1451
1452         if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
1453                 goto partial;
1454
1455         if (!trace_seq_puts(s, ")"))
1456                 goto partial;
1457
1458         data = (u8 *)&field[1];
1459         for (i = 0; i < tp->nr_args; i++)
1460                 if (!tp->args[i].type->print(s, tp->args[i].name,
1461                                              data + tp->args[i].offset, field))
1462                         goto partial;
1463
1464         if (!trace_seq_puts(s, "\n"))
1465                 goto partial;
1466
1467         return TRACE_TYPE_HANDLED;
1468 partial:
1469         return TRACE_TYPE_PARTIAL_LINE;
1470 }
1471
1472 enum print_line_t
1473 print_kretprobe_event(struct trace_iterator *iter, int flags,
1474                       struct trace_event *event)
1475 {
1476         struct kretprobe_trace_entry_head *field;
1477         struct trace_seq *s = &iter->seq;
1478         struct trace_probe *tp;
1479         u8 *data;
1480         int i;
1481
1482         field = (struct kretprobe_trace_entry_head *)iter->ent;
1483         tp = container_of(event, struct trace_probe, call.event);
1484
1485         if (!trace_seq_printf(s, "%s: (", tp->call.name))
1486                 goto partial;
1487
1488         if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
1489                 goto partial;
1490
1491         if (!trace_seq_puts(s, " <- "))
1492                 goto partial;
1493
1494         if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET))
1495                 goto partial;
1496
1497         if (!trace_seq_puts(s, ")"))
1498                 goto partial;
1499
1500         data = (u8 *)&field[1];
1501         for (i = 0; i < tp->nr_args; i++)
1502                 if (!tp->args[i].type->print(s, tp->args[i].name,
1503                                              data + tp->args[i].offset, field))
1504                         goto partial;
1505
1506         if (!trace_seq_puts(s, "\n"))
1507                 goto partial;
1508
1509         return TRACE_TYPE_HANDLED;
1510 partial:
1511         return TRACE_TYPE_PARTIAL_LINE;
1512 }
1513
1514 static int probe_event_enable(struct ftrace_event_call *call)
1515 {
1516         struct trace_probe *tp = (struct trace_probe *)call->data;
1517
1518         tp->flags |= TP_FLAG_TRACE;
1519         if (probe_is_return(tp))
1520                 return enable_kretprobe(&tp->rp);
1521         else
1522                 return enable_kprobe(&tp->rp.kp);
1523 }
1524
1525 static void probe_event_disable(struct ftrace_event_call *call)
1526 {
1527         struct trace_probe *tp = (struct trace_probe *)call->data;
1528
1529         tp->flags &= ~TP_FLAG_TRACE;
1530         if (!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE))) {
1531                 if (probe_is_return(tp))
1532                         disable_kretprobe(&tp->rp);
1533                 else
1534                         disable_kprobe(&tp->rp.kp);
1535         }
1536 }
1537
1538 #undef DEFINE_FIELD
1539 #define DEFINE_FIELD(type, item, name, is_signed)                       \
1540         do {                                                            \
1541                 ret = trace_define_field(event_call, #type, name,       \
1542                                          offsetof(typeof(field), item), \
1543                                          sizeof(field.item), is_signed, \
1544                                          FILTER_OTHER);                 \
1545                 if (ret)                                                \
1546                         return ret;                                     \
1547         } while (0)
1548
1549 static int kprobe_event_define_fields(struct ftrace_event_call *event_call)
1550 {
1551         int ret, i;
1552         struct kprobe_trace_entry_head field;
1553         struct trace_probe *tp = (struct trace_probe *)event_call->data;
1554
1555         DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
1556         /* Set argument names as fields */
1557         for (i = 0; i < tp->nr_args; i++) {
1558                 ret = trace_define_field(event_call, tp->args[i].type->fmttype,
1559                                          tp->args[i].name,
1560                                          sizeof(field) + tp->args[i].offset,
1561                                          tp->args[i].type->size,
1562                                          tp->args[i].type->is_signed,
1563                                          FILTER_OTHER);
1564                 if (ret)
1565                         return ret;
1566         }
1567         return 0;
1568 }
1569
1570 static int kretprobe_event_define_fields(struct ftrace_event_call *event_call)
1571 {
1572         int ret, i;
1573         struct kretprobe_trace_entry_head field;
1574         struct trace_probe *tp = (struct trace_probe *)event_call->data;
1575
1576         DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
1577         DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
1578         /* Set argument names as fields */
1579         for (i = 0; i < tp->nr_args; i++) {
1580                 ret = trace_define_field(event_call, tp->args[i].type->fmttype,
1581                                          tp->args[i].name,
1582                                          sizeof(field) + tp->args[i].offset,
1583                                          tp->args[i].type->size,
1584                                          tp->args[i].type->is_signed,
1585                                          FILTER_OTHER);
1586                 if (ret)
1587                         return ret;
1588         }
1589         return 0;
1590 }
1591
1592 static int __set_print_fmt(struct trace_probe *tp, char *buf, int len)
1593 {
1594         int i;
1595         int pos = 0;
1596
1597         const char *fmt, *arg;
1598
1599         if (!probe_is_return(tp)) {
1600                 fmt = "(%lx)";
1601                 arg = "REC->" FIELD_STRING_IP;
1602         } else {
1603                 fmt = "(%lx <- %lx)";
1604                 arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP;
1605         }
1606
1607         /* When len=0, we just calculate the needed length */
1608 #define LEN_OR_ZERO (len ? len - pos : 0)
1609
1610         pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt);
1611
1612         for (i = 0; i < tp->nr_args; i++) {
1613                 pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s",
1614                                 tp->args[i].name, tp->args[i].type->fmt);
1615         }
1616
1617         pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg);
1618
1619         for (i = 0; i < tp->nr_args; i++) {
1620                 if (strcmp(tp->args[i].type->name, "string") == 0)
1621                         pos += snprintf(buf + pos, LEN_OR_ZERO,
1622                                         ", __get_str(%s)",
1623                                         tp->args[i].name);
1624                 else
1625                         pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s",
1626                                         tp->args[i].name);
1627         }
1628
1629 #undef LEN_OR_ZERO
1630
1631         /* return the length of print_fmt */
1632         return pos;
1633 }
1634
1635 static int set_print_fmt(struct trace_probe *tp)
1636 {
1637         int len;
1638         char *print_fmt;
1639
1640         /* First: called with 0 length to calculate the needed length */
1641         len = __set_print_fmt(tp, NULL, 0);
1642         print_fmt = kmalloc(len + 1, GFP_KERNEL);
1643         if (!print_fmt)
1644                 return -ENOMEM;
1645
1646         /* Second: actually write the @print_fmt */
1647         __set_print_fmt(tp, print_fmt, len + 1);
1648         tp->call.print_fmt = print_fmt;
1649
1650         return 0;
1651 }
1652
1653 #ifdef CONFIG_PERF_EVENTS
1654
1655 /* Kprobe profile handler */
1656 static __kprobes void kprobe_perf_func(struct kprobe *kp,
1657                                          struct pt_regs *regs)
1658 {
1659         struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
1660         struct ftrace_event_call *call = &tp->call;
1661         struct kprobe_trace_entry_head *entry;
1662         struct hlist_head *head;
1663         int size, __size, dsize;
1664         int rctx;
1665
1666         dsize = __get_data_size(tp, regs);
1667         __size = sizeof(*entry) + tp->size + dsize;
1668         size = ALIGN(__size + sizeof(u32), sizeof(u64));
1669         size -= sizeof(u32);
1670         if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
1671                      "profile buffer not large enough"))
1672                 return;
1673
1674         entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
1675         if (!entry)
1676                 return;
1677
1678         entry->ip = (unsigned long)kp->addr;
1679         memset(&entry[1], 0, dsize);
1680         store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
1681
1682         head = this_cpu_ptr(call->perf_events);
1683         perf_trace_buf_submit(entry, size, rctx, entry->ip, 1, regs, head);
1684 }
1685
1686 /* Kretprobe profile handler */
1687 static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri,
1688                                             struct pt_regs *regs)
1689 {
1690         struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
1691         struct ftrace_event_call *call = &tp->call;
1692         struct kretprobe_trace_entry_head *entry;
1693         struct hlist_head *head;
1694         int size, __size, dsize;
1695         int rctx;
1696
1697         dsize = __get_data_size(tp, regs);
1698         __size = sizeof(*entry) + tp->size + dsize;
1699         size = ALIGN(__size + sizeof(u32), sizeof(u64));
1700         size -= sizeof(u32);
1701         if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
1702                      "profile buffer not large enough"))
1703                 return;
1704
1705         entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
1706         if (!entry)
1707                 return;
1708
1709         entry->func = (unsigned long)tp->rp.kp.addr;
1710         entry->ret_ip = (unsigned long)ri->ret_addr;
1711         store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
1712
1713         head = this_cpu_ptr(call->perf_events);
1714         perf_trace_buf_submit(entry, size, rctx, entry->ret_ip, 1, regs, head);
1715 }
1716
1717 static int probe_perf_enable(struct ftrace_event_call *call)
1718 {
1719         struct trace_probe *tp = (struct trace_probe *)call->data;
1720
1721         tp->flags |= TP_FLAG_PROFILE;
1722
1723         if (probe_is_return(tp))
1724                 return enable_kretprobe(&tp->rp);
1725         else
1726                 return enable_kprobe(&tp->rp.kp);
1727 }
1728
1729 static void probe_perf_disable(struct ftrace_event_call *call)
1730 {
1731         struct trace_probe *tp = (struct trace_probe *)call->data;
1732
1733         tp->flags &= ~TP_FLAG_PROFILE;
1734
1735         if (!(tp->flags & TP_FLAG_TRACE)) {
1736                 if (probe_is_return(tp))
1737                         disable_kretprobe(&tp->rp);
1738                 else
1739                         disable_kprobe(&tp->rp.kp);
1740         }
1741 }
1742 #endif  /* CONFIG_PERF_EVENTS */
1743
1744 static __kprobes
1745 int kprobe_register(struct ftrace_event_call *event, enum trace_reg type)
1746 {
1747         switch (type) {
1748         case TRACE_REG_REGISTER:
1749                 return probe_event_enable(event);
1750         case TRACE_REG_UNREGISTER:
1751                 probe_event_disable(event);
1752                 return 0;
1753
1754 #ifdef CONFIG_PERF_EVENTS
1755         case TRACE_REG_PERF_REGISTER:
1756                 return probe_perf_enable(event);
1757         case TRACE_REG_PERF_UNREGISTER:
1758                 probe_perf_disable(event);
1759                 return 0;
1760 #endif
1761         }
1762         return 0;
1763 }
1764
1765 static __kprobes
1766 int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
1767 {
1768         struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
1769
1770         if (tp->flags & TP_FLAG_TRACE)
1771                 kprobe_trace_func(kp, regs);
1772 #ifdef CONFIG_PERF_EVENTS
1773         if (tp->flags & TP_FLAG_PROFILE)
1774                 kprobe_perf_func(kp, regs);
1775 #endif
1776         return 0;       /* We don't tweek kernel, so just return 0 */
1777 }
1778
1779 static __kprobes
1780 int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
1781 {
1782         struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
1783
1784         if (tp->flags & TP_FLAG_TRACE)
1785                 kretprobe_trace_func(ri, regs);
1786 #ifdef CONFIG_PERF_EVENTS
1787         if (tp->flags & TP_FLAG_PROFILE)
1788                 kretprobe_perf_func(ri, regs);
1789 #endif
1790         return 0;       /* We don't tweek kernel, so just return 0 */
1791 }
1792
1793 static struct trace_event_functions kretprobe_funcs = {
1794         .trace          = print_kretprobe_event
1795 };
1796
1797 static struct trace_event_functions kprobe_funcs = {
1798         .trace          = print_kprobe_event
1799 };
1800
1801 static int register_probe_event(struct trace_probe *tp)
1802 {
1803         struct ftrace_event_call *call = &tp->call;
1804         int ret;
1805
1806         /* Initialize ftrace_event_call */
1807         INIT_LIST_HEAD(&call->class->fields);
1808         if (probe_is_return(tp)) {
1809                 call->event.funcs = &kretprobe_funcs;
1810                 call->class->define_fields = kretprobe_event_define_fields;
1811         } else {
1812                 call->event.funcs = &kprobe_funcs;
1813                 call->class->define_fields = kprobe_event_define_fields;
1814         }
1815         if (set_print_fmt(tp) < 0)
1816                 return -ENOMEM;
1817         ret = register_ftrace_event(&call->event);
1818         if (!ret) {
1819                 kfree(call->print_fmt);
1820                 return -ENODEV;
1821         }
1822         call->flags = 0;
1823         call->class->reg = kprobe_register;
1824         call->data = tp;
1825         ret = trace_add_event_call(call);
1826         if (ret) {
1827                 pr_info("Failed to register kprobe event: %s\n", call->name);
1828                 kfree(call->print_fmt);
1829                 unregister_ftrace_event(&call->event);
1830         }
1831         return ret;
1832 }
1833
1834 static void unregister_probe_event(struct trace_probe *tp)
1835 {
1836         /* tp->event is unregistered in trace_remove_event_call() */
1837         trace_remove_event_call(&tp->call);
1838         kfree(tp->call.print_fmt);
1839 }
1840
1841 /* Make a debugfs interface for controlling probe points */
1842 static __init int init_kprobe_trace(void)
1843 {
1844         struct dentry *d_tracer;
1845         struct dentry *entry;
1846
1847         d_tracer = tracing_init_dentry();
1848         if (!d_tracer)
1849                 return 0;
1850
1851         entry = debugfs_create_file("kprobe_events", 0644, d_tracer,
1852                                     NULL, &kprobe_events_ops);
1853
1854         /* Event list interface */
1855         if (!entry)
1856                 pr_warning("Could not create debugfs "
1857                            "'kprobe_events' entry\n");
1858
1859         /* Profile interface */
1860         entry = debugfs_create_file("kprobe_profile", 0444, d_tracer,
1861                                     NULL, &kprobe_profile_ops);
1862
1863         if (!entry)
1864                 pr_warning("Could not create debugfs "
1865                            "'kprobe_profile' entry\n");
1866         return 0;
1867 }
1868 fs_initcall(init_kprobe_trace);
1869
1870
1871 #ifdef CONFIG_FTRACE_STARTUP_TEST
1872
1873 /*
1874  * The "__used" keeps gcc from removing the function symbol
1875  * from the kallsyms table.
1876  */
1877 static __used int kprobe_trace_selftest_target(int a1, int a2, int a3,
1878                                                int a4, int a5, int a6)
1879 {
1880         return a1 + a2 + a3 + a4 + a5 + a6;
1881 }
1882
1883 static __init int kprobe_trace_self_tests_init(void)
1884 {
1885         int ret, warn = 0;
1886         int (*target)(int, int, int, int, int, int);
1887         struct trace_probe *tp;
1888
1889         target = kprobe_trace_selftest_target;
1890
1891         pr_info("Testing kprobe tracing: ");
1892
1893         ret = command_trace_probe("p:testprobe kprobe_trace_selftest_target "
1894                                   "$stack $stack0 +0($stack)");
1895         if (WARN_ON_ONCE(ret)) {
1896                 pr_warning("error on probing function entry.\n");
1897                 warn++;
1898         } else {
1899                 /* Enable trace point */
1900                 tp = find_probe_event("testprobe", KPROBE_EVENT_SYSTEM);
1901                 if (WARN_ON_ONCE(tp == NULL)) {
1902                         pr_warning("error on getting new probe.\n");
1903                         warn++;
1904                 } else
1905                         probe_event_enable(&tp->call);
1906         }
1907
1908         ret = command_trace_probe("r:testprobe2 kprobe_trace_selftest_target "
1909                                   "$retval");
1910         if (WARN_ON_ONCE(ret)) {
1911                 pr_warning("error on probing function return.\n");
1912                 warn++;
1913         } else {
1914                 /* Enable trace point */
1915                 tp = find_probe_event("testprobe2", KPROBE_EVENT_SYSTEM);
1916                 if (WARN_ON_ONCE(tp == NULL)) {
1917                         pr_warning("error on getting new probe.\n");
1918                         warn++;
1919                 } else
1920                         probe_event_enable(&tp->call);
1921         }
1922
1923         if (warn)
1924                 goto end;
1925
1926         ret = target(1, 2, 3, 4, 5, 6);
1927
1928         ret = command_trace_probe("-:testprobe");
1929         if (WARN_ON_ONCE(ret)) {
1930                 pr_warning("error on deleting a probe.\n");
1931                 warn++;
1932         }
1933
1934         ret = command_trace_probe("-:testprobe2");
1935         if (WARN_ON_ONCE(ret)) {
1936                 pr_warning("error on deleting a probe.\n");
1937                 warn++;
1938         }
1939
1940 end:
1941         cleanup_all_probes();
1942         if (warn)
1943                 pr_cont("NG: Some tests are failed. Please check them.\n");
1944         else
1945                 pr_cont("OK\n");
1946         return 0;
1947 }
1948
1949 late_initcall(kprobe_trace_self_tests_init);
1950
1951 #endif