// SPDX-License-Identifier: GPL-2.0
|
/*
|
* Common code for probe-based Dynamic events.
|
*
|
* This code was copied from kernel/trace/trace_kprobe.c written by
|
* Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
|
*
|
* Updates to make this generic:
|
* Copyright (C) IBM Corporation, 2010-2011
|
* Author: Srikar Dronamraju
|
*/
|
#define pr_fmt(fmt) "trace_probe: " fmt
|
|
#include "trace_probe.h"
|
|
#undef C
|
#define C(a, b) b
|
|
static const char *trace_probe_err_text[] = { ERRORS };
|
|
static const char *reserved_field_names[] = {
|
"common_type",
|
"common_flags",
|
"common_preempt_count",
|
"common_pid",
|
"common_tgid",
|
FIELD_STRING_IP,
|
FIELD_STRING_RETIP,
|
FIELD_STRING_FUNC,
|
};
|
|
/* Printing in basic type function template */
|
#define DEFINE_BASIC_PRINT_TYPE_FUNC(tname, type, fmt) \
|
int PRINT_TYPE_FUNC_NAME(tname)(struct trace_seq *s, void *data, void *ent)\
|
{ \
|
trace_seq_printf(s, fmt, *(type *)data); \
|
return !trace_seq_has_overflowed(s); \
|
} \
|
const char PRINT_TYPE_FMT_NAME(tname)[] = fmt;
|
|
DEFINE_BASIC_PRINT_TYPE_FUNC(u8, u8, "%u")
|
DEFINE_BASIC_PRINT_TYPE_FUNC(u16, u16, "%u")
|
DEFINE_BASIC_PRINT_TYPE_FUNC(u32, u32, "%u")
|
DEFINE_BASIC_PRINT_TYPE_FUNC(u64, u64, "%Lu")
|
DEFINE_BASIC_PRINT_TYPE_FUNC(s8, s8, "%d")
|
DEFINE_BASIC_PRINT_TYPE_FUNC(s16, s16, "%d")
|
DEFINE_BASIC_PRINT_TYPE_FUNC(s32, s32, "%d")
|
DEFINE_BASIC_PRINT_TYPE_FUNC(s64, s64, "%Ld")
|
DEFINE_BASIC_PRINT_TYPE_FUNC(x8, u8, "0x%x")
|
DEFINE_BASIC_PRINT_TYPE_FUNC(x16, u16, "0x%x")
|
DEFINE_BASIC_PRINT_TYPE_FUNC(x32, u32, "0x%x")
|
DEFINE_BASIC_PRINT_TYPE_FUNC(x64, u64, "0x%Lx")
|
|
int PRINT_TYPE_FUNC_NAME(symbol)(struct trace_seq *s, void *data, void *ent)
|
{
|
trace_seq_printf(s, "%pS", (void *)*(unsigned long *)data);
|
return !trace_seq_has_overflowed(s);
|
}
|
const char PRINT_TYPE_FMT_NAME(symbol)[] = "%pS";
|
|
/* Print type function for string type */
|
int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, void *data, void *ent)
|
{
|
int len = *(u32 *)data >> 16;
|
|
if (!len)
|
trace_seq_puts(s, "(fault)");
|
else
|
trace_seq_printf(s, "\"%s\"",
|
(const char *)get_loc_data(data, ent));
|
return !trace_seq_has_overflowed(s);
|
}
|
|
const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\"";
|
|
/* Fetch type information table */
|
static const struct fetch_type probe_fetch_types[] = {
|
/* Special types */
|
__ASSIGN_FETCH_TYPE("string", string, string, sizeof(u32), 1,
|
"__data_loc char[]"),
|
__ASSIGN_FETCH_TYPE("ustring", string, string, sizeof(u32), 1,
|
"__data_loc char[]"),
|
/* Basic types */
|
ASSIGN_FETCH_TYPE(u8, u8, 0),
|
ASSIGN_FETCH_TYPE(u16, u16, 0),
|
ASSIGN_FETCH_TYPE(u32, u32, 0),
|
ASSIGN_FETCH_TYPE(u64, u64, 0),
|
ASSIGN_FETCH_TYPE(s8, u8, 1),
|
ASSIGN_FETCH_TYPE(s16, u16, 1),
|
ASSIGN_FETCH_TYPE(s32, u32, 1),
|
ASSIGN_FETCH_TYPE(s64, u64, 1),
|
ASSIGN_FETCH_TYPE_ALIAS(x8, u8, u8, 0),
|
ASSIGN_FETCH_TYPE_ALIAS(x16, u16, u16, 0),
|
ASSIGN_FETCH_TYPE_ALIAS(x32, u32, u32, 0),
|
ASSIGN_FETCH_TYPE_ALIAS(x64, u64, u64, 0),
|
ASSIGN_FETCH_TYPE_ALIAS(symbol, ADDR_FETCH_TYPE, ADDR_FETCH_TYPE, 0),
|
|
ASSIGN_FETCH_TYPE_END
|
};
|
|
static const struct fetch_type *find_fetch_type(const char *type)
|
{
|
int i;
|
|
if (!type)
|
type = DEFAULT_FETCH_TYPE_STR;
|
|
/* Special case: bitfield */
|
if (*type == 'b') {
|
unsigned long bs;
|
|
type = strchr(type, '/');
|
if (!type)
|
goto fail;
|
|
type++;
|
if (kstrtoul(type, 0, &bs))
|
goto fail;
|
|
switch (bs) {
|
case 8:
|
return find_fetch_type("u8");
|
case 16:
|
return find_fetch_type("u16");
|
case 32:
|
return find_fetch_type("u32");
|
case 64:
|
return find_fetch_type("u64");
|
default:
|
goto fail;
|
}
|
}
|
|
for (i = 0; probe_fetch_types[i].name; i++) {
|
if (strcmp(type, probe_fetch_types[i].name) == 0)
|
return &probe_fetch_types[i];
|
}
|
|
fail:
|
return NULL;
|
}
|
|
static struct trace_probe_log trace_probe_log;
|
|
void trace_probe_log_init(const char *subsystem, int argc, const char **argv)
|
{
|
trace_probe_log.subsystem = subsystem;
|
trace_probe_log.argc = argc;
|
trace_probe_log.argv = argv;
|
trace_probe_log.index = 0;
|
}
|
|
void trace_probe_log_clear(void)
|
{
|
memset(&trace_probe_log, 0, sizeof(trace_probe_log));
|
}
|
|
void trace_probe_log_set_index(int index)
|
{
|
trace_probe_log.index = index;
|
}
|
|
void __trace_probe_log_err(int offset, int err_type)
|
{
|
char *command, *p;
|
int i, len = 0, pos = 0;
|
|
if (!trace_probe_log.argv)
|
return;
|
|
/* Recalcurate the length and allocate buffer */
|
for (i = 0; i < trace_probe_log.argc; i++) {
|
if (i == trace_probe_log.index)
|
pos = len;
|
len += strlen(trace_probe_log.argv[i]) + 1;
|
}
|
command = kzalloc(len, GFP_KERNEL);
|
if (!command)
|
return;
|
|
if (trace_probe_log.index >= trace_probe_log.argc) {
|
/**
|
* Set the error position is next to the last arg + space.
|
* Note that len includes the terminal null and the cursor
|
* appaers at pos + 1.
|
*/
|
pos = len;
|
offset = 0;
|
}
|
|
/* And make a command string from argv array */
|
p = command;
|
for (i = 0; i < trace_probe_log.argc; i++) {
|
len = strlen(trace_probe_log.argv[i]);
|
strcpy(p, trace_probe_log.argv[i]);
|
p[len] = ' ';
|
p += len + 1;
|
}
|
*(p - 1) = '\0';
|
|
tracing_log_err(NULL, trace_probe_log.subsystem, command,
|
trace_probe_err_text, err_type, pos + offset);
|
|
kfree(command);
|
}
|
|
/* Split symbol and offset. */
|
int traceprobe_split_symbol_offset(char *symbol, long *offset)
|
{
|
char *tmp;
|
int ret;
|
|
if (!offset)
|
return -EINVAL;
|
|
tmp = strpbrk(symbol, "+-");
|
if (tmp) {
|
ret = kstrtol(tmp, 0, offset);
|
if (ret)
|
return ret;
|
*tmp = '\0';
|
} else
|
*offset = 0;
|
|
return 0;
|
}
|
|
/* @buf must has MAX_EVENT_NAME_LEN size */
|
int traceprobe_parse_event_name(const char **pevent, const char **pgroup,
|
char *buf, int offset)
|
{
|
const char *slash, *event = *pevent;
|
int len;
|
|
slash = strchr(event, '/');
|
if (slash) {
|
if (slash == event) {
|
trace_probe_log_err(offset, NO_GROUP_NAME);
|
return -EINVAL;
|
}
|
if (slash - event + 1 > MAX_EVENT_NAME_LEN) {
|
trace_probe_log_err(offset, GROUP_TOO_LONG);
|
return -EINVAL;
|
}
|
strlcpy(buf, event, slash - event + 1);
|
if (!is_good_name(buf)) {
|
trace_probe_log_err(offset, BAD_GROUP_NAME);
|
return -EINVAL;
|
}
|
*pgroup = buf;
|
*pevent = slash + 1;
|
offset += slash - event + 1;
|
event = *pevent;
|
}
|
len = strlen(event);
|
if (len == 0) {
|
trace_probe_log_err(offset, NO_EVENT_NAME);
|
return -EINVAL;
|
} else if (len > MAX_EVENT_NAME_LEN) {
|
trace_probe_log_err(offset, EVENT_TOO_LONG);
|
return -EINVAL;
|
}
|
if (!is_good_name(event)) {
|
trace_probe_log_err(offset, BAD_EVENT_NAME);
|
return -EINVAL;
|
}
|
return 0;
|
}
|
|
#define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
|
|
static int parse_probe_vars(char *arg, const struct fetch_type *t,
|
struct fetch_insn *code, unsigned int flags, int offs)
|
{
|
unsigned long param;
|
int ret = 0;
|
int len;
|
|
if (strcmp(arg, "retval") == 0) {
|
if (flags & TPARG_FL_RETURN) {
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code->op = FETCH_OP_RETVAL;
|
} else {
|
trace_probe_log_err(offs, RETVAL_ON_PROBE);
|
ret = -EINVAL;
|
}
|
} else if ((len = str_has_prefix(arg, "stack"))) {
|
if (arg[len] == '\0') {
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code->op = FETCH_OP_STACKP;
|
} else if (isdigit(arg[len])) {
|
ret = kstrtoul(arg + len, 10, ¶m);
|
if (ret) {
|
goto inval_var;
|
} else if ((flags & TPARG_FL_KERNEL) &&
|
param > PARAM_MAX_STACK) {
|
trace_probe_log_err(offs, BAD_STACK_NUM);
|
ret = -EINVAL;
|
} else {
|
code->op = FETCH_OP_STACK;
|
code->param = (unsigned int)param;
|
}
|
} else
|
goto inval_var;
|
} else if (strcmp(arg, "comm") == 0 || strcmp(arg, "COMM") == 0) {
|
code->op = FETCH_OP_COMM;
|
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
|
} else if (((flags & TPARG_FL_MASK) ==
|
(TPARG_FL_KERNEL | TPARG_FL_FENTRY)) &&
|
(len = str_has_prefix(arg, "arg"))) {
|
ret = kstrtoul(arg + len, 10, ¶m);
|
if (ret) {
|
goto inval_var;
|
} else if (!param || param > PARAM_MAX_STACK) {
|
trace_probe_log_err(offs, BAD_ARG_NUM);
|
return -EINVAL;
|
}
|
code->op = FETCH_OP_ARG;
|
code->param = (unsigned int)param - 1;
|
#endif
|
} else
|
goto inval_var;
|
|
return ret;
|
|
inval_var:
|
trace_probe_log_err(offs, BAD_VAR);
|
return -EINVAL;
|
}
|
|
static int str_to_immediate(char *str, unsigned long *imm)
|
{
|
if (isdigit(str[0]))
|
return kstrtoul(str, 0, imm);
|
else if (str[0] == '-')
|
return kstrtol(str, 0, (long *)imm);
|
else if (str[0] == '+')
|
return kstrtol(str + 1, 0, (long *)imm);
|
return -EINVAL;
|
}
|
|
static int __parse_imm_string(char *str, char **pbuf, int offs)
|
{
|
size_t len = strlen(str);
|
|
if (str[len - 1] != '"') {
|
trace_probe_log_err(offs + len, IMMSTR_NO_CLOSE);
|
return -EINVAL;
|
}
|
*pbuf = kstrndup(str, len - 1, GFP_KERNEL);
|
return 0;
|
}
|
|
/* Recursive argument parser */
|
static int
|
parse_probe_arg(char *arg, const struct fetch_type *type,
|
struct fetch_insn **pcode, struct fetch_insn *end,
|
unsigned int flags, int offs)
|
{
|
struct fetch_insn *code = *pcode;
|
unsigned long param;
|
int deref = FETCH_OP_DEREF;
|
long offset = 0;
|
char *tmp;
|
int ret = 0;
|
|
switch (arg[0]) {
|
case '$':
|
ret = parse_probe_vars(arg + 1, type, code, flags, offs);
|
break;
|
|
case '%': /* named register */
|
ret = regs_query_register_offset(arg + 1);
|
if (ret >= 0) {
|
code->op = FETCH_OP_REG;
|
code->param = (unsigned int)ret;
|
ret = 0;
|
} else
|
trace_probe_log_err(offs, BAD_REG_NAME);
|
break;
|
|
case '@': /* memory, file-offset or symbol */
|
if (isdigit(arg[1])) {
|
ret = kstrtoul(arg + 1, 0, ¶m);
|
if (ret) {
|
trace_probe_log_err(offs, BAD_MEM_ADDR);
|
break;
|
}
|
/* load address */
|
code->op = FETCH_OP_IMM;
|
code->immediate = param;
|
} else if (arg[1] == '+') {
|
/* kprobes don't support file offsets */
|
if (flags & TPARG_FL_KERNEL) {
|
trace_probe_log_err(offs, FILE_ON_KPROBE);
|
return -EINVAL;
|
}
|
ret = kstrtol(arg + 2, 0, &offset);
|
if (ret) {
|
trace_probe_log_err(offs, BAD_FILE_OFFS);
|
break;
|
}
|
|
code->op = FETCH_OP_FOFFS;
|
code->immediate = (unsigned long)offset; // imm64?
|
} else {
|
/* uprobes don't support symbols */
|
if (!(flags & TPARG_FL_KERNEL)) {
|
trace_probe_log_err(offs, SYM_ON_UPROBE);
|
return -EINVAL;
|
}
|
/* Preserve symbol for updating */
|
code->op = FETCH_NOP_SYMBOL;
|
code->data = kstrdup(arg + 1, GFP_KERNEL);
|
if (!code->data)
|
return -ENOMEM;
|
if (++code == end) {
|
trace_probe_log_err(offs, TOO_MANY_OPS);
|
return -EINVAL;
|
}
|
code->op = FETCH_OP_IMM;
|
code->immediate = 0;
|
}
|
/* These are fetching from memory */
|
if (++code == end) {
|
trace_probe_log_err(offs, TOO_MANY_OPS);
|
return -EINVAL;
|
}
|
*pcode = code;
|
code->op = FETCH_OP_DEREF;
|
code->offset = offset;
|
break;
|
|
case '+': /* deref memory */
|
case '-':
|
if (arg[1] == 'u') {
|
deref = FETCH_OP_UDEREF;
|
arg[1] = arg[0];
|
arg++;
|
}
|
if (arg[0] == '+')
|
arg++; /* Skip '+', because kstrtol() rejects it. */
|
tmp = strchr(arg, '(');
|
if (!tmp) {
|
trace_probe_log_err(offs, DEREF_NEED_BRACE);
|
return -EINVAL;
|
}
|
*tmp = '\0';
|
ret = kstrtol(arg, 0, &offset);
|
if (ret) {
|
trace_probe_log_err(offs, BAD_DEREF_OFFS);
|
break;
|
}
|
offs += (tmp + 1 - arg) + (arg[0] != '-' ? 1 : 0);
|
arg = tmp + 1;
|
tmp = strrchr(arg, ')');
|
if (!tmp) {
|
trace_probe_log_err(offs + strlen(arg),
|
DEREF_OPEN_BRACE);
|
return -EINVAL;
|
} else {
|
const struct fetch_type *t2 = find_fetch_type(NULL);
|
|
*tmp = '\0';
|
ret = parse_probe_arg(arg, t2, &code, end, flags, offs);
|
if (ret)
|
break;
|
if (code->op == FETCH_OP_COMM ||
|
code->op == FETCH_OP_DATA) {
|
trace_probe_log_err(offs, COMM_CANT_DEREF);
|
return -EINVAL;
|
}
|
if (++code == end) {
|
trace_probe_log_err(offs, TOO_MANY_OPS);
|
return -EINVAL;
|
}
|
*pcode = code;
|
|
code->op = deref;
|
code->offset = offset;
|
}
|
break;
|
case '\\': /* Immediate value */
|
if (arg[1] == '"') { /* Immediate string */
|
ret = __parse_imm_string(arg + 2, &tmp, offs + 2);
|
if (ret)
|
break;
|
code->op = FETCH_OP_DATA;
|
code->data = tmp;
|
} else {
|
ret = str_to_immediate(arg + 1, &code->immediate);
|
if (ret)
|
trace_probe_log_err(offs + 1, BAD_IMM);
|
else
|
code->op = FETCH_OP_IMM;
|
}
|
break;
|
}
|
if (!ret && code->op == FETCH_OP_NOP) {
|
/* Parsed, but do not find fetch method */
|
trace_probe_log_err(offs, BAD_FETCH_ARG);
|
ret = -EINVAL;
|
}
|
return ret;
|
}
|
|
#define BYTES_TO_BITS(nb) ((BITS_PER_LONG * (nb)) / sizeof(long))
|
|
/* Bitfield type needs to be parsed into a fetch function */
|
static int __parse_bitfield_probe_arg(const char *bf,
|
const struct fetch_type *t,
|
struct fetch_insn **pcode)
|
{
|
struct fetch_insn *code = *pcode;
|
unsigned long bw, bo;
|
char *tail;
|
|
if (*bf != 'b')
|
return 0;
|
|
bw = simple_strtoul(bf + 1, &tail, 0); /* Use simple one */
|
|
if (bw == 0 || *tail != '@')
|
return -EINVAL;
|
|
bf = tail + 1;
|
bo = simple_strtoul(bf, &tail, 0);
|
|
if (tail == bf || *tail != '/')
|
return -EINVAL;
|
code++;
|
if (code->op != FETCH_OP_NOP)
|
return -EINVAL;
|
*pcode = code;
|
|
code->op = FETCH_OP_MOD_BF;
|
code->lshift = BYTES_TO_BITS(t->size) - (bw + bo);
|
code->rshift = BYTES_TO_BITS(t->size) - bw;
|
code->basesize = t->size;
|
|
return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0;
|
}
|
|
/* String length checking wrapper */
|
static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
|
struct probe_arg *parg, unsigned int flags, int offset)
|
{
|
struct fetch_insn *code, *scode, *tmp = NULL;
|
char *t, *t2, *t3;
|
int ret, len;
|
|
len = strlen(arg);
|
if (len > MAX_ARGSTR_LEN) {
|
trace_probe_log_err(offset, ARG_TOO_LONG);
|
return -EINVAL;
|
} else if (len == 0) {
|
trace_probe_log_err(offset, NO_ARG_BODY);
|
return -EINVAL;
|
}
|
|
parg->comm = kstrdup(arg, GFP_KERNEL);
|
if (!parg->comm)
|
return -ENOMEM;
|
|
t = strchr(arg, ':');
|
if (t) {
|
*t = '\0';
|
t2 = strchr(++t, '[');
|
if (t2) {
|
*t2++ = '\0';
|
t3 = strchr(t2, ']');
|
if (!t3) {
|
offset += t2 + strlen(t2) - arg;
|
trace_probe_log_err(offset,
|
ARRAY_NO_CLOSE);
|
return -EINVAL;
|
} else if (t3[1] != '\0') {
|
trace_probe_log_err(offset + t3 + 1 - arg,
|
BAD_ARRAY_SUFFIX);
|
return -EINVAL;
|
}
|
*t3 = '\0';
|
if (kstrtouint(t2, 0, &parg->count) || !parg->count) {
|
trace_probe_log_err(offset + t2 - arg,
|
BAD_ARRAY_NUM);
|
return -EINVAL;
|
}
|
if (parg->count > MAX_ARRAY_LEN) {
|
trace_probe_log_err(offset + t2 - arg,
|
ARRAY_TOO_BIG);
|
return -EINVAL;
|
}
|
}
|
}
|
|
/*
|
* Since $comm and immediate string can not be dereferred,
|
* we can find those by strcmp.
|
*/
|
if (strcmp(arg, "$comm") == 0 || strcmp(arg, "$COMM") == 0 ||
|
strncmp(arg, "\\\"", 2) == 0) {
|
/* The type of $comm must be "string", and not an array. */
|
if (parg->count || (t && strcmp(t, "string")))
|
return -EINVAL;
|
parg->type = find_fetch_type("string");
|
} else
|
parg->type = find_fetch_type(t);
|
if (!parg->type) {
|
trace_probe_log_err(offset + (t ? (t - arg) : 0), BAD_TYPE);
|
return -EINVAL;
|
}
|
parg->offset = *size;
|
*size += parg->type->size * (parg->count ?: 1);
|
|
if (parg->count) {
|
len = strlen(parg->type->fmttype) + 6;
|
parg->fmt = kmalloc(len, GFP_KERNEL);
|
if (!parg->fmt)
|
return -ENOMEM;
|
snprintf(parg->fmt, len, "%s[%d]", parg->type->fmttype,
|
parg->count);
|
}
|
|
code = tmp = kcalloc(FETCH_INSN_MAX, sizeof(*code), GFP_KERNEL);
|
if (!code)
|
return -ENOMEM;
|
code[FETCH_INSN_MAX - 1].op = FETCH_OP_END;
|
|
ret = parse_probe_arg(arg, parg->type, &code, &code[FETCH_INSN_MAX - 1],
|
flags, offset);
|
if (ret)
|
goto fail;
|
|
/* Store operation */
|
if (!strcmp(parg->type->name, "string") ||
|
!strcmp(parg->type->name, "ustring")) {
|
if (code->op != FETCH_OP_DEREF && code->op != FETCH_OP_UDEREF &&
|
code->op != FETCH_OP_IMM && code->op != FETCH_OP_COMM &&
|
code->op != FETCH_OP_DATA) {
|
trace_probe_log_err(offset + (t ? (t - arg) : 0),
|
BAD_STRING);
|
ret = -EINVAL;
|
goto fail;
|
}
|
if ((code->op == FETCH_OP_IMM || code->op == FETCH_OP_COMM ||
|
code->op == FETCH_OP_DATA) || parg->count) {
|
/*
|
* IMM, DATA and COMM is pointing actual address, those
|
* must be kept, and if parg->count != 0, this is an
|
* array of string pointers instead of string address
|
* itself.
|
*/
|
code++;
|
if (code->op != FETCH_OP_NOP) {
|
trace_probe_log_err(offset, TOO_MANY_OPS);
|
ret = -EINVAL;
|
goto fail;
|
}
|
}
|
/* If op == DEREF, replace it with STRING */
|
if (!strcmp(parg->type->name, "ustring") ||
|
code->op == FETCH_OP_UDEREF)
|
code->op = FETCH_OP_ST_USTRING;
|
else
|
code->op = FETCH_OP_ST_STRING;
|
code->size = parg->type->size;
|
parg->dynamic = true;
|
} else if (code->op == FETCH_OP_DEREF) {
|
code->op = FETCH_OP_ST_MEM;
|
code->size = parg->type->size;
|
} else if (code->op == FETCH_OP_UDEREF) {
|
code->op = FETCH_OP_ST_UMEM;
|
code->size = parg->type->size;
|
} else {
|
code++;
|
if (code->op != FETCH_OP_NOP) {
|
trace_probe_log_err(offset, TOO_MANY_OPS);
|
ret = -EINVAL;
|
goto fail;
|
}
|
code->op = FETCH_OP_ST_RAW;
|
code->size = parg->type->size;
|
}
|
scode = code;
|
/* Modify operation */
|
if (t != NULL) {
|
ret = __parse_bitfield_probe_arg(t, parg->type, &code);
|
if (ret) {
|
trace_probe_log_err(offset + t - arg, BAD_BITFIELD);
|
goto fail;
|
}
|
}
|
/* Loop(Array) operation */
|
if (parg->count) {
|
if (scode->op != FETCH_OP_ST_MEM &&
|
scode->op != FETCH_OP_ST_STRING &&
|
scode->op != FETCH_OP_ST_USTRING) {
|
trace_probe_log_err(offset + (t ? (t - arg) : 0),
|
BAD_STRING);
|
ret = -EINVAL;
|
goto fail;
|
}
|
code++;
|
if (code->op != FETCH_OP_NOP) {
|
trace_probe_log_err(offset, TOO_MANY_OPS);
|
ret = -EINVAL;
|
goto fail;
|
}
|
code->op = FETCH_OP_LP_ARRAY;
|
code->param = parg->count;
|
}
|
code++;
|
code->op = FETCH_OP_END;
|
|
/* Shrink down the code buffer */
|
parg->code = kcalloc(code - tmp + 1, sizeof(*code), GFP_KERNEL);
|
if (!parg->code)
|
ret = -ENOMEM;
|
else
|
memcpy(parg->code, tmp, sizeof(*code) * (code - tmp + 1));
|
|
fail:
|
if (ret) {
|
for (code = tmp; code < tmp + FETCH_INSN_MAX; code++)
|
if (code->op == FETCH_NOP_SYMBOL ||
|
code->op == FETCH_OP_DATA)
|
kfree(code->data);
|
}
|
kfree(tmp);
|
|
return ret;
|
}
|
|
/* Return 1 if name is reserved or already used by another argument */
|
static int traceprobe_conflict_field_name(const char *name,
|
struct probe_arg *args, int narg)
|
{
|
int i;
|
|
for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++)
|
if (strcmp(reserved_field_names[i], name) == 0)
|
return 1;
|
|
for (i = 0; i < narg; i++)
|
if (strcmp(args[i].name, name) == 0)
|
return 1;
|
|
return 0;
|
}
|
|
int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, char *arg,
|
unsigned int flags)
|
{
|
struct probe_arg *parg = &tp->args[i];
|
char *body;
|
|
/* Increment count for freeing args in error case */
|
tp->nr_args++;
|
|
body = strchr(arg, '=');
|
if (body) {
|
if (body - arg > MAX_ARG_NAME_LEN) {
|
trace_probe_log_err(0, ARG_NAME_TOO_LONG);
|
return -EINVAL;
|
} else if (body == arg) {
|
trace_probe_log_err(0, NO_ARG_NAME);
|
return -EINVAL;
|
}
|
parg->name = kmemdup_nul(arg, body - arg, GFP_KERNEL);
|
body++;
|
} else {
|
/* If argument name is omitted, set "argN" */
|
parg->name = kasprintf(GFP_KERNEL, "arg%d", i + 1);
|
body = arg;
|
}
|
if (!parg->name)
|
return -ENOMEM;
|
|
if (!is_good_name(parg->name)) {
|
trace_probe_log_err(0, BAD_ARG_NAME);
|
return -EINVAL;
|
}
|
if (traceprobe_conflict_field_name(parg->name, tp->args, i)) {
|
trace_probe_log_err(0, USED_ARG_NAME);
|
return -EINVAL;
|
}
|
/* Parse fetch argument */
|
return traceprobe_parse_probe_arg_body(body, &tp->size, parg, flags,
|
body - arg);
|
}
|
|
void traceprobe_free_probe_arg(struct probe_arg *arg)
|
{
|
struct fetch_insn *code = arg->code;
|
|
while (code && code->op != FETCH_OP_END) {
|
if (code->op == FETCH_NOP_SYMBOL ||
|
code->op == FETCH_OP_DATA)
|
kfree(code->data);
|
code++;
|
}
|
kfree(arg->code);
|
kfree(arg->name);
|
kfree(arg->comm);
|
kfree(arg->fmt);
|
}
|
|
int traceprobe_update_arg(struct probe_arg *arg)
|
{
|
struct fetch_insn *code = arg->code;
|
long offset;
|
char *tmp;
|
char c;
|
int ret = 0;
|
|
while (code && code->op != FETCH_OP_END) {
|
if (code->op == FETCH_NOP_SYMBOL) {
|
if (code[1].op != FETCH_OP_IMM)
|
return -EINVAL;
|
|
tmp = strpbrk(code->data, "+-");
|
if (tmp)
|
c = *tmp;
|
ret = traceprobe_split_symbol_offset(code->data,
|
&offset);
|
if (ret)
|
return ret;
|
|
code[1].immediate =
|
(unsigned long)kallsyms_lookup_name(code->data);
|
if (tmp)
|
*tmp = c;
|
if (!code[1].immediate)
|
return -ENOENT;
|
code[1].immediate += offset;
|
}
|
code++;
|
}
|
return 0;
|
}
|
|
/* When len=0, we just calculate the needed length */
|
#define LEN_OR_ZERO (len ? len - pos : 0)
|
static int __set_print_fmt(struct trace_probe *tp, char *buf, int len,
|
bool is_return)
|
{
|
struct probe_arg *parg;
|
int i, j;
|
int pos = 0;
|
const char *fmt, *arg;
|
|
if (!is_return) {
|
fmt = "(%lx)";
|
arg = "REC->" FIELD_STRING_IP;
|
} else {
|
fmt = "(%lx <- %lx)";
|
arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP;
|
}
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt);
|
|
for (i = 0; i < tp->nr_args; i++) {
|
parg = tp->args + i;
|
pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=", parg->name);
|
if (parg->count) {
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "{%s",
|
parg->type->fmt);
|
for (j = 1; j < parg->count; j++)
|
pos += snprintf(buf + pos, LEN_OR_ZERO, ",%s",
|
parg->type->fmt);
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "}");
|
} else
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "%s",
|
parg->type->fmt);
|
}
|
|
pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg);
|
|
for (i = 0; i < tp->nr_args; i++) {
|
parg = tp->args + i;
|
if (parg->count) {
|
if ((strcmp(parg->type->name, "string") == 0) ||
|
(strcmp(parg->type->name, "ustring") == 0))
|
fmt = ", __get_str(%s[%d])";
|
else
|
fmt = ", REC->%s[%d]";
|
for (j = 0; j < parg->count; j++)
|
pos += snprintf(buf + pos, LEN_OR_ZERO,
|
fmt, parg->name, j);
|
} else {
|
if ((strcmp(parg->type->name, "string") == 0) ||
|
(strcmp(parg->type->name, "ustring") == 0))
|
fmt = ", __get_str(%s)";
|
else
|
fmt = ", REC->%s";
|
pos += snprintf(buf + pos, LEN_OR_ZERO,
|
fmt, parg->name);
|
}
|
}
|
|
/* return the length of print_fmt */
|
return pos;
|
}
|
#undef LEN_OR_ZERO
|
|
int traceprobe_set_print_fmt(struct trace_probe *tp, bool is_return)
|
{
|
struct trace_event_call *call = trace_probe_event_call(tp);
|
int len;
|
char *print_fmt;
|
|
/* First: called with 0 length to calculate the needed length */
|
len = __set_print_fmt(tp, NULL, 0, is_return);
|
print_fmt = kmalloc(len + 1, GFP_KERNEL);
|
if (!print_fmt)
|
return -ENOMEM;
|
|
/* Second: actually write the @print_fmt */
|
__set_print_fmt(tp, print_fmt, len + 1, is_return);
|
call->print_fmt = print_fmt;
|
|
return 0;
|
}
|
|
int traceprobe_define_arg_fields(struct trace_event_call *event_call,
|
size_t offset, struct trace_probe *tp)
|
{
|
int ret, i;
|
|
/* Set argument names as fields */
|
for (i = 0; i < tp->nr_args; i++) {
|
struct probe_arg *parg = &tp->args[i];
|
const char *fmt = parg->type->fmttype;
|
int size = parg->type->size;
|
|
if (parg->fmt)
|
fmt = parg->fmt;
|
if (parg->count)
|
size *= parg->count;
|
ret = trace_define_field(event_call, fmt, parg->name,
|
offset + parg->offset, size,
|
parg->type->is_signed,
|
FILTER_OTHER);
|
if (ret)
|
return ret;
|
}
|
return 0;
|
}
|
|
static void trace_probe_event_free(struct trace_probe_event *tpe)
|
{
|
kfree(tpe->class.system);
|
kfree(tpe->call.name);
|
kfree(tpe->call.print_fmt);
|
kfree(tpe);
|
}
|
|
int trace_probe_append(struct trace_probe *tp, struct trace_probe *to)
|
{
|
if (trace_probe_has_sibling(tp))
|
return -EBUSY;
|
|
list_del_init(&tp->list);
|
trace_probe_event_free(tp->event);
|
|
tp->event = to->event;
|
list_add_tail(&tp->list, trace_probe_probe_list(to));
|
|
return 0;
|
}
|
|
void trace_probe_unlink(struct trace_probe *tp)
|
{
|
list_del_init(&tp->list);
|
if (list_empty(trace_probe_probe_list(tp)))
|
trace_probe_event_free(tp->event);
|
tp->event = NULL;
|
}
|
|
void trace_probe_cleanup(struct trace_probe *tp)
|
{
|
int i;
|
|
for (i = 0; i < tp->nr_args; i++)
|
traceprobe_free_probe_arg(&tp->args[i]);
|
|
if (tp->event)
|
trace_probe_unlink(tp);
|
}
|
|
int trace_probe_init(struct trace_probe *tp, const char *event,
|
const char *group, bool alloc_filter)
|
{
|
struct trace_event_call *call;
|
size_t size = sizeof(struct trace_probe_event);
|
int ret = 0;
|
|
if (!event || !group)
|
return -EINVAL;
|
|
if (alloc_filter)
|
size += sizeof(struct trace_uprobe_filter);
|
|
tp->event = kzalloc(size, GFP_KERNEL);
|
if (!tp->event)
|
return -ENOMEM;
|
|
INIT_LIST_HEAD(&tp->event->files);
|
INIT_LIST_HEAD(&tp->event->class.fields);
|
INIT_LIST_HEAD(&tp->event->probes);
|
INIT_LIST_HEAD(&tp->list);
|
list_add(&tp->list, &tp->event->probes);
|
|
call = trace_probe_event_call(tp);
|
call->class = &tp->event->class;
|
call->name = kstrdup(event, GFP_KERNEL);
|
if (!call->name) {
|
ret = -ENOMEM;
|
goto error;
|
}
|
|
tp->event->class.system = kstrdup(group, GFP_KERNEL);
|
if (!tp->event->class.system) {
|
ret = -ENOMEM;
|
goto error;
|
}
|
|
return 0;
|
|
error:
|
trace_probe_cleanup(tp);
|
return ret;
|
}
|
|
static struct trace_event_call *
|
find_trace_event_call(const char *system, const char *event_name)
|
{
|
struct trace_event_call *tp_event;
|
const char *name;
|
|
list_for_each_entry(tp_event, &ftrace_events, list) {
|
if (!tp_event->class->system ||
|
strcmp(system, tp_event->class->system))
|
continue;
|
name = trace_event_name(tp_event);
|
if (!name || strcmp(event_name, name))
|
continue;
|
return tp_event;
|
}
|
|
return NULL;
|
}
|
|
int trace_probe_register_event_call(struct trace_probe *tp)
|
{
|
struct trace_event_call *call = trace_probe_event_call(tp);
|
int ret;
|
|
lockdep_assert_held(&event_mutex);
|
|
if (find_trace_event_call(trace_probe_group_name(tp),
|
trace_probe_name(tp)))
|
return -EEXIST;
|
|
ret = register_trace_event(&call->event);
|
if (!ret)
|
return -ENODEV;
|
|
ret = trace_add_event_call(call);
|
if (ret)
|
unregister_trace_event(&call->event);
|
|
return ret;
|
}
|
|
int trace_probe_add_file(struct trace_probe *tp, struct trace_event_file *file)
|
{
|
struct event_file_link *link;
|
|
link = kmalloc(sizeof(*link), GFP_KERNEL);
|
if (!link)
|
return -ENOMEM;
|
|
link->file = file;
|
INIT_LIST_HEAD(&link->list);
|
list_add_tail_rcu(&link->list, &tp->event->files);
|
trace_probe_set_flag(tp, TP_FLAG_TRACE);
|
return 0;
|
}
|
|
struct event_file_link *trace_probe_get_file_link(struct trace_probe *tp,
|
struct trace_event_file *file)
|
{
|
struct event_file_link *link;
|
|
trace_probe_for_each_link(link, tp) {
|
if (link->file == file)
|
return link;
|
}
|
|
return NULL;
|
}
|
|
int trace_probe_remove_file(struct trace_probe *tp,
|
struct trace_event_file *file)
|
{
|
struct event_file_link *link;
|
|
link = trace_probe_get_file_link(tp, file);
|
if (!link)
|
return -ENOENT;
|
|
list_del_rcu(&link->list);
|
synchronize_rcu();
|
kfree(link);
|
|
if (list_empty(&tp->event->files))
|
trace_probe_clear_flag(tp, TP_FLAG_TRACE);
|
|
return 0;
|
}
|
|
/*
|
* Return the smallest index of different type argument (start from 1).
|
* If all argument types and name are same, return 0.
|
*/
|
int trace_probe_compare_arg_type(struct trace_probe *a, struct trace_probe *b)
|
{
|
int i;
|
|
/* In case of more arguments */
|
if (a->nr_args < b->nr_args)
|
return a->nr_args + 1;
|
if (a->nr_args > b->nr_args)
|
return b->nr_args + 1;
|
|
for (i = 0; i < a->nr_args; i++) {
|
if ((b->nr_args <= i) ||
|
((a->args[i].type != b->args[i].type) ||
|
(a->args[i].count != b->args[i].count) ||
|
strcmp(a->args[i].name, b->args[i].name)))
|
return i + 1;
|
}
|
|
return 0;
|
}
|
|
bool trace_probe_match_command_args(struct trace_probe *tp,
|
int argc, const char **argv)
|
{
|
char buf[MAX_ARGSTR_LEN + 1];
|
int i;
|
|
if (tp->nr_args < argc)
|
return false;
|
|
for (i = 0; i < argc; i++) {
|
snprintf(buf, sizeof(buf), "%s=%s",
|
tp->args[i].name, tp->args[i].comm);
|
if (strcmp(buf, argv[i]))
|
return false;
|
}
|
return true;
|
}
|
