zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/kernel/trace/trace_kprobe.c b/ap/os/linux/linux-3.4.x/kernel/trace/trace_kprobe.c
new file mode 100644
index 0000000..580a05e
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/kernel/trace/trace_kprobe.c
@@ -0,0 +1,2127 @@
+/*
+ * Kprobes-based tracing events
+ *
+ * Created by Masami Hiramatsu <mhiramat@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/module.h>
+#include <linux/uaccess.h>
+#include <linux/kprobes.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/smp.h>
+#include <linux/debugfs.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/ptrace.h>
+#include <linux/perf_event.h>
+#include <linux/stringify.h>
+#include <linux/limits.h>
+#include <asm/bitsperlong.h>
+
+#include "trace.h"
+#include "trace_output.h"
+
+#define MAX_TRACE_ARGS 128
+#define MAX_ARGSTR_LEN 63
+#define MAX_EVENT_NAME_LEN 64
+#define MAX_STRING_SIZE PATH_MAX
+#define KPROBE_EVENT_SYSTEM "kprobes"
+
+/* Reserved field names */
+#define FIELD_STRING_IP "__probe_ip"
+#define FIELD_STRING_RETIP "__probe_ret_ip"
+#define FIELD_STRING_FUNC "__probe_func"
+
+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 function type */
+typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *,
+ void *);
+#define PRINT_TYPE_FUNC_NAME(type) print_type_##type
+#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type
+
+/* Printing in basic type function template */
+#define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt, cast) \
+static __kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \
+ const char *name, \
+ void *data, void *ent)\
+{ \
+ return trace_seq_printf(s, " %s=" fmt, name, (cast)*(type *)data);\
+} \
+static const char PRINT_TYPE_FMT_NAME(type)[] = fmt;
+
+DEFINE_BASIC_PRINT_TYPE_FUNC(u8, "%x", unsigned int)
+DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "%x", unsigned int)
+DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "%lx", unsigned long)
+DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "%llx", unsigned long long)
+DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d", int)
+DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d", int)
+DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%ld", long)
+DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%lld", long long)
+
+/* data_rloc: data relative location, compatible with u32 */
+#define make_data_rloc(len, roffs) \
+ (((u32)(len) << 16) | ((u32)(roffs) & 0xffff))
+#define get_rloc_len(dl) ((u32)(dl) >> 16)
+#define get_rloc_offs(dl) ((u32)(dl) & 0xffff)
+
+static inline void *get_rloc_data(u32 *dl)
+{
+ return (u8 *)dl + get_rloc_offs(*dl);
+}
+
+/* For data_loc conversion */
+static inline void *get_loc_data(u32 *dl, void *ent)
+{
+ return (u8 *)ent + get_rloc_offs(*dl);
+}
+
+/*
+ * Convert data_rloc to data_loc:
+ * data_rloc stores the offset from data_rloc itself, but data_loc
+ * stores the offset from event entry.
+ */
+#define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs))
+
+/* For defining macros, define string/string_size types */
+typedef u32 string;
+typedef u32 string_size;
+
+/* Print type function for string type */
+static __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s,
+ const char *name,
+ void *data, void *ent)
+{
+ int len = *(u32 *)data >> 16;
+
+ if (!len)
+ return trace_seq_printf(s, " %s=(fault)", name);
+ else
+ return trace_seq_printf(s, " %s=\"%s\"", name,
+ (const char *)get_loc_data(data, ent));
+}
+static const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\"";
+
+/* Data fetch function type */
+typedef void (*fetch_func_t)(struct pt_regs *, void *, void *);
+
+struct fetch_param {
+ fetch_func_t fn;
+ void *data;
+};
+
+static __kprobes void call_fetch(struct fetch_param *fprm,
+ struct pt_regs *regs, void *dest)
+{
+ return fprm->fn(regs, fprm->data, dest);
+}
+
+#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type
+/*
+ * Define macro for basic types - we don't need to define s* types, because
+ * we have to care only about bitwidth at recording time.
+ */
+#define DEFINE_BASIC_FETCH_FUNCS(method) \
+DEFINE_FETCH_##method(u8) \
+DEFINE_FETCH_##method(u16) \
+DEFINE_FETCH_##method(u32) \
+DEFINE_FETCH_##method(u64)
+
+#define CHECK_FETCH_FUNCS(method, fn) \
+ (((FETCH_FUNC_NAME(method, u8) == fn) || \
+ (FETCH_FUNC_NAME(method, u16) == fn) || \
+ (FETCH_FUNC_NAME(method, u32) == fn) || \
+ (FETCH_FUNC_NAME(method, u64) == fn) || \
+ (FETCH_FUNC_NAME(method, string) == fn) || \
+ (FETCH_FUNC_NAME(method, string_size) == fn)) \
+ && (fn != NULL))
+
+/* Data fetch function templates */
+#define DEFINE_FETCH_reg(type) \
+static __kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, \
+ void *offset, void *dest) \
+{ \
+ *(type *)dest = (type)regs_get_register(regs, \
+ (unsigned int)((unsigned long)offset)); \
+}
+DEFINE_BASIC_FETCH_FUNCS(reg)
+/* No string on the register */
+#define fetch_reg_string NULL
+#define fetch_reg_string_size NULL
+
+#define DEFINE_FETCH_stack(type) \
+static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\
+ void *offset, void *dest) \
+{ \
+ *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \
+ (unsigned int)((unsigned long)offset)); \
+}
+DEFINE_BASIC_FETCH_FUNCS(stack)
+/* No string on the stack entry */
+#define fetch_stack_string NULL
+#define fetch_stack_string_size NULL
+
+#define DEFINE_FETCH_retval(type) \
+static __kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs,\
+ void *dummy, void *dest) \
+{ \
+ *(type *)dest = (type)regs_return_value(regs); \
+}
+DEFINE_BASIC_FETCH_FUNCS(retval)
+/* No string on the retval */
+#define fetch_retval_string NULL
+#define fetch_retval_string_size NULL
+
+#define DEFINE_FETCH_memory(type) \
+static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\
+ void *addr, void *dest) \
+{ \
+ type retval; \
+ if (probe_kernel_address(addr, retval)) \
+ *(type *)dest = 0; \
+ else \
+ *(type *)dest = retval; \
+}
+DEFINE_BASIC_FETCH_FUNCS(memory)
+/*
+ * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
+ * length and relative data location.
+ */
+static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs,
+ void *addr, void *dest)
+{
+ long ret;
+ int maxlen = get_rloc_len(*(u32 *)dest);
+ u8 *dst = get_rloc_data(dest);
+ u8 *src = addr;
+ mm_segment_t old_fs = get_fs();
+ if (!maxlen)
+ return;
+ /*
+ * Try to get string again, since the string can be changed while
+ * probing.
+ */
+ set_fs(KERNEL_DS);
+ pagefault_disable();
+ do
+ ret = __copy_from_user_inatomic(dst++, src++, 1);
+ while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen);
+ dst[-1] = '\0';
+ pagefault_enable();
+ set_fs(old_fs);
+
+ if (ret < 0) { /* Failed to fetch string */
+ ((u8 *)get_rloc_data(dest))[0] = '\0';
+ *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest));
+ } else
+ *(u32 *)dest = make_data_rloc(src - (u8 *)addr,
+ get_rloc_offs(*(u32 *)dest));
+}
+/* Return the length of string -- including null terminal byte */
+static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs,
+ void *addr, void *dest)
+{
+ int ret, len = 0;
+ u8 c;
+ mm_segment_t old_fs = get_fs();
+
+ set_fs(KERNEL_DS);
+ pagefault_disable();
+ do {
+ ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1);
+ len++;
+ } while (c && ret == 0 && len < MAX_STRING_SIZE);
+ pagefault_enable();
+ set_fs(old_fs);
+
+ if (ret < 0) /* Failed to check the length */
+ *(u32 *)dest = 0;
+ else
+ *(u32 *)dest = len;
+}
+
+/* Memory fetching by symbol */
+struct symbol_cache {
+ char *symbol;
+ long offset;
+ unsigned long addr;
+};
+
+static unsigned long update_symbol_cache(struct symbol_cache *sc)
+{
+ sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol);
+ if (sc->addr)
+ sc->addr += sc->offset;
+ return sc->addr;
+}
+
+static void free_symbol_cache(struct symbol_cache *sc)
+{
+ kfree(sc->symbol);
+ kfree(sc);
+}
+
+static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset)
+{
+ struct symbol_cache *sc;
+
+ if (!sym || strlen(sym) == 0)
+ return NULL;
+ sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL);
+ if (!sc)
+ return NULL;
+
+ sc->symbol = kstrdup(sym, GFP_KERNEL);
+ if (!sc->symbol) {
+ kfree(sc);
+ return NULL;
+ }
+ sc->offset = offset;
+
+ update_symbol_cache(sc);
+ return sc;
+}
+
+#define DEFINE_FETCH_symbol(type) \
+static __kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs,\
+ void *data, void *dest) \
+{ \
+ struct symbol_cache *sc = data; \
+ if (sc->addr) \
+ fetch_memory_##type(regs, (void *)sc->addr, dest); \
+ else \
+ *(type *)dest = 0; \
+}
+DEFINE_BASIC_FETCH_FUNCS(symbol)
+DEFINE_FETCH_symbol(string)
+DEFINE_FETCH_symbol(string_size)
+
+/* Dereference memory access function */
+struct deref_fetch_param {
+ struct fetch_param orig;
+ long offset;
+};
+
+#define DEFINE_FETCH_deref(type) \
+static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\
+ void *data, void *dest) \
+{ \
+ struct deref_fetch_param *dprm = data; \
+ unsigned long addr; \
+ call_fetch(&dprm->orig, regs, &addr); \
+ if (addr) { \
+ addr += dprm->offset; \
+ fetch_memory_##type(regs, (void *)addr, dest); \
+ } else \
+ *(type *)dest = 0; \
+}
+DEFINE_BASIC_FETCH_FUNCS(deref)
+DEFINE_FETCH_deref(string)
+DEFINE_FETCH_deref(string_size)
+
+static __kprobes void update_deref_fetch_param(struct deref_fetch_param *data)
+{
+ if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
+ update_deref_fetch_param(data->orig.data);
+ else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
+ update_symbol_cache(data->orig.data);
+}
+
+static __kprobes void free_deref_fetch_param(struct deref_fetch_param *data)
+{
+ if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
+ free_deref_fetch_param(data->orig.data);
+ else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
+ free_symbol_cache(data->orig.data);
+ kfree(data);
+}
+
+/* Bitfield fetch function */
+struct bitfield_fetch_param {
+ struct fetch_param orig;
+ unsigned char hi_shift;
+ unsigned char low_shift;
+};
+
+#define DEFINE_FETCH_bitfield(type) \
+static __kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs,\
+ void *data, void *dest) \
+{ \
+ struct bitfield_fetch_param *bprm = data; \
+ type buf = 0; \
+ call_fetch(&bprm->orig, regs, &buf); \
+ if (buf) { \
+ buf <<= bprm->hi_shift; \
+ buf >>= bprm->low_shift; \
+ } \
+ *(type *)dest = buf; \
+}
+DEFINE_BASIC_FETCH_FUNCS(bitfield)
+#define fetch_bitfield_string NULL
+#define fetch_bitfield_string_size NULL
+
+static __kprobes void
+update_bitfield_fetch_param(struct bitfield_fetch_param *data)
+{
+ /*
+ * Don't check the bitfield itself, because this must be the
+ * last fetch function.
+ */
+ if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
+ update_deref_fetch_param(data->orig.data);
+ else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
+ update_symbol_cache(data->orig.data);
+}
+
+static __kprobes void
+free_bitfield_fetch_param(struct bitfield_fetch_param *data)
+{
+ /*
+ * Don't check the bitfield itself, because this must be the
+ * last fetch function.
+ */
+ if (CHECK_FETCH_FUNCS(deref, data->orig.fn))
+ free_deref_fetch_param(data->orig.data);
+ else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn))
+ free_symbol_cache(data->orig.data);
+ kfree(data);
+}
+
+/* Default (unsigned long) fetch type */
+#define __DEFAULT_FETCH_TYPE(t) u##t
+#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
+#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG)
+#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE)
+
+/* Fetch types */
+enum {
+ FETCH_MTD_reg = 0,
+ FETCH_MTD_stack,
+ FETCH_MTD_retval,
+ FETCH_MTD_memory,
+ FETCH_MTD_symbol,
+ FETCH_MTD_deref,
+ FETCH_MTD_bitfield,
+ FETCH_MTD_END,
+};
+
+#define ASSIGN_FETCH_FUNC(method, type) \
+ [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type)
+
+#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
+ {.name = _name, \
+ .size = _size, \
+ .is_signed = sign, \
+ .print = PRINT_TYPE_FUNC_NAME(ptype), \
+ .fmt = PRINT_TYPE_FMT_NAME(ptype), \
+ .fmttype = _fmttype, \
+ .fetch = { \
+ASSIGN_FETCH_FUNC(reg, ftype), \
+ASSIGN_FETCH_FUNC(stack, ftype), \
+ASSIGN_FETCH_FUNC(retval, ftype), \
+ASSIGN_FETCH_FUNC(memory, ftype), \
+ASSIGN_FETCH_FUNC(symbol, ftype), \
+ASSIGN_FETCH_FUNC(deref, ftype), \
+ASSIGN_FETCH_FUNC(bitfield, ftype), \
+ } \
+ }
+
+#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \
+ __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype)
+
+#define FETCH_TYPE_STRING 0
+#define FETCH_TYPE_STRSIZE 1
+
+/* Fetch type information table */
+static const struct fetch_type {
+ const char *name; /* Name of type */
+ size_t size; /* Byte size of type */
+ int is_signed; /* Signed flag */
+ print_type_func_t print; /* Print functions */
+ const char *fmt; /* Fromat string */
+ const char *fmttype; /* Name in format file */
+ /* Fetch functions */
+ fetch_func_t fetch[FETCH_MTD_END];
+} fetch_type_table[] = {
+ /* Special types */
+ [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string,
+ sizeof(u32), 1, "__data_loc char[]"),
+ [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32,
+ string_size, sizeof(u32), 0, "u32"),
+ /* 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),
+};
+
+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 (strict_strtoul(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; i < ARRAY_SIZE(fetch_type_table); i++)
+ if (strcmp(type, fetch_type_table[i].name) == 0)
+ return &fetch_type_table[i];
+fail:
+ return NULL;
+}
+
+/* Special function : only accept unsigned long */
+static __kprobes void fetch_stack_address(struct pt_regs *regs,
+ void *dummy, void *dest)
+{
+ *(unsigned long *)dest = kernel_stack_pointer(regs);
+}
+
+static fetch_func_t get_fetch_size_function(const struct fetch_type *type,
+ fetch_func_t orig_fn)
+{
+ int i;
+
+ if (type != &fetch_type_table[FETCH_TYPE_STRING])
+ return NULL; /* Only string type needs size function */
+ for (i = 0; i < FETCH_MTD_END; i++)
+ if (type->fetch[i] == orig_fn)
+ return fetch_type_table[FETCH_TYPE_STRSIZE].fetch[i];
+
+ WARN_ON(1); /* This should not happen */
+ return NULL;
+}
+
+/**
+ * Kprobe event core functions
+ */
+
+struct probe_arg {
+ struct fetch_param fetch;
+ struct fetch_param fetch_size;
+ unsigned int offset; /* Offset from argument entry */
+ const char *name; /* Name of this argument */
+ const char *comm; /* Command of this argument */
+ const struct fetch_type *type; /* Type of this argument */
+};
+
+/* Flags for trace_probe */
+#define TP_FLAG_TRACE 1
+#define TP_FLAG_PROFILE 2
+#define TP_FLAG_REGISTERED 4
+
+struct trace_probe {
+ struct list_head list;
+ struct kretprobe rp; /* Use rp.kp for kprobe use */
+ unsigned long nhit;
+ unsigned int flags; /* For TP_FLAG_* */
+ const char *symbol; /* symbol name */
+ struct ftrace_event_class class;
+ struct ftrace_event_call call;
+ ssize_t size; /* trace entry size */
+ unsigned int nr_args;
+ struct probe_arg args[];
+};
+
+#define SIZEOF_TRACE_PROBE(n) \
+ (offsetof(struct trace_probe, args) + \
+ (sizeof(struct probe_arg) * (n)))
+
+
+static __kprobes int trace_probe_is_return(struct trace_probe *tp)
+{
+ return tp->rp.handler != NULL;
+}
+
+static __kprobes const char *trace_probe_symbol(struct trace_probe *tp)
+{
+ return tp->symbol ? tp->symbol : "unknown";
+}
+
+static __kprobes unsigned long trace_probe_offset(struct trace_probe *tp)
+{
+ return tp->rp.kp.offset;
+}
+
+static __kprobes bool trace_probe_is_enabled(struct trace_probe *tp)
+{
+ return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE));
+}
+
+static __kprobes bool trace_probe_is_registered(struct trace_probe *tp)
+{
+ return !!(tp->flags & TP_FLAG_REGISTERED);
+}
+
+static __kprobes bool trace_probe_has_gone(struct trace_probe *tp)
+{
+ return !!(kprobe_gone(&tp->rp.kp));
+}
+
+static __kprobes bool trace_probe_within_module(struct trace_probe *tp,
+ struct module *mod)
+{
+ int len = strlen(mod->name);
+ const char *name = trace_probe_symbol(tp);
+ return strncmp(mod->name, name, len) == 0 && name[len] == ':';
+}
+
+static __kprobes bool trace_probe_is_on_module(struct trace_probe *tp)
+{
+ return !!strchr(trace_probe_symbol(tp), ':');
+}
+
+static int register_probe_event(struct trace_probe *tp);
+static void unregister_probe_event(struct trace_probe *tp);
+
+static DEFINE_MUTEX(probe_lock);
+static LIST_HEAD(probe_list);
+
+static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs);
+static int kretprobe_dispatcher(struct kretprobe_instance *ri,
+ struct pt_regs *regs);
+
+/* Check the name is good for event/group/fields */
+static int is_good_name(const char *name)
+{
+ if (!isalpha(*name) && *name != '_')
+ return 0;
+ while (*++name != '\0') {
+ if (!isalpha(*name) && !isdigit(*name) && *name != '_')
+ return 0;
+ }
+ return 1;
+}
+
+/*
+ * Allocate new trace_probe and initialize it (including kprobes).
+ */
+static struct trace_probe *alloc_trace_probe(const char *group,
+ const char *event,
+ void *addr,
+ const char *symbol,
+ unsigned long offs,
+ int nargs, int is_return)
+{
+ struct trace_probe *tp;
+ int ret = -ENOMEM;
+
+ tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL);
+ if (!tp)
+ return ERR_PTR(ret);
+
+ if (symbol) {
+ tp->symbol = kstrdup(symbol, GFP_KERNEL);
+ if (!tp->symbol)
+ goto error;
+ tp->rp.kp.symbol_name = tp->symbol;
+ tp->rp.kp.offset = offs;
+ } else
+ tp->rp.kp.addr = addr;
+
+ if (is_return)
+ tp->rp.handler = kretprobe_dispatcher;
+ else
+ tp->rp.kp.pre_handler = kprobe_dispatcher;
+
+ if (!event || !is_good_name(event)) {
+ ret = -EINVAL;
+ goto error;
+ }
+
+ tp->call.class = &tp->class;
+ tp->call.name = kstrdup(event, GFP_KERNEL);
+ if (!tp->call.name)
+ goto error;
+
+ if (!group || !is_good_name(group)) {
+ ret = -EINVAL;
+ goto error;
+ }
+
+ tp->class.system = kstrdup(group, GFP_KERNEL);
+ if (!tp->class.system)
+ goto error;
+
+ INIT_LIST_HEAD(&tp->list);
+ return tp;
+error:
+ kfree(tp->call.name);
+ kfree(tp->symbol);
+ kfree(tp);
+ return ERR_PTR(ret);
+}
+
+static void update_probe_arg(struct probe_arg *arg)
+{
+ if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn))
+ update_bitfield_fetch_param(arg->fetch.data);
+ else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
+ update_deref_fetch_param(arg->fetch.data);
+ else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
+ update_symbol_cache(arg->fetch.data);
+}
+
+static void free_probe_arg(struct probe_arg *arg)
+{
+ if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn))
+ free_bitfield_fetch_param(arg->fetch.data);
+ else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn))
+ free_deref_fetch_param(arg->fetch.data);
+ else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn))
+ free_symbol_cache(arg->fetch.data);
+ kfree(arg->name);
+ kfree(arg->comm);
+}
+
+static void free_trace_probe(struct trace_probe *tp)
+{
+ int i;
+
+ for (i = 0; i < tp->nr_args; i++)
+ free_probe_arg(&tp->args[i]);
+
+ kfree(tp->call.class->system);
+ kfree(tp->call.name);
+ kfree(tp->symbol);
+ kfree(tp);
+}
+
+static struct trace_probe *find_trace_probe(const char *event,
+ const char *group)
+{
+ struct trace_probe *tp;
+
+ list_for_each_entry(tp, &probe_list, list)
+ if (strcmp(tp->call.name, event) == 0 &&
+ strcmp(tp->call.class->system, group) == 0)
+ return tp;
+ return NULL;
+}
+
+/* Enable trace_probe - @flag must be TP_FLAG_TRACE or TP_FLAG_PROFILE */
+static int enable_trace_probe(struct trace_probe *tp, int flag)
+{
+ int ret = 0;
+
+ tp->flags |= flag;
+ if (trace_probe_is_enabled(tp) && trace_probe_is_registered(tp) &&
+ !trace_probe_has_gone(tp)) {
+ if (trace_probe_is_return(tp))
+ ret = enable_kretprobe(&tp->rp);
+ else
+ ret = enable_kprobe(&tp->rp.kp);
+ }
+
+ return ret;
+}
+
+/* Disable trace_probe - @flag must be TP_FLAG_TRACE or TP_FLAG_PROFILE */
+static void disable_trace_probe(struct trace_probe *tp, int flag)
+{
+ tp->flags &= ~flag;
+ if (!trace_probe_is_enabled(tp) && trace_probe_is_registered(tp)) {
+ if (trace_probe_is_return(tp))
+ disable_kretprobe(&tp->rp);
+ else
+ disable_kprobe(&tp->rp.kp);
+ }
+}
+
+/* Internal register function - just handle k*probes and flags */
+static int __register_trace_probe(struct trace_probe *tp)
+{
+ int i, ret;
+
+ if (trace_probe_is_registered(tp))
+ return -EINVAL;
+
+ for (i = 0; i < tp->nr_args; i++)
+ update_probe_arg(&tp->args[i]);
+
+ /* Set/clear disabled flag according to tp->flag */
+ if (trace_probe_is_enabled(tp))
+ tp->rp.kp.flags &= ~KPROBE_FLAG_DISABLED;
+ else
+ tp->rp.kp.flags |= KPROBE_FLAG_DISABLED;
+
+ if (trace_probe_is_return(tp))
+ ret = register_kretprobe(&tp->rp);
+ else
+ ret = register_kprobe(&tp->rp.kp);
+
+ if (ret == 0)
+ tp->flags |= TP_FLAG_REGISTERED;
+ else {
+ pr_warning("Could not insert probe at %s+%lu: %d\n",
+ trace_probe_symbol(tp), trace_probe_offset(tp), ret);
+ if (ret == -ENOENT && trace_probe_is_on_module(tp)) {
+ pr_warning("This probe might be able to register after"
+ "target module is loaded. Continue.\n");
+ ret = 0;
+ } else if (ret == -EILSEQ) {
+ pr_warning("Probing address(0x%p) is not an "
+ "instruction boundary.\n",
+ tp->rp.kp.addr);
+ ret = -EINVAL;
+ }
+ }
+
+ return ret;
+}
+
+/* Internal unregister function - just handle k*probes and flags */
+static void __unregister_trace_probe(struct trace_probe *tp)
+{
+ if (trace_probe_is_registered(tp)) {
+ if (trace_probe_is_return(tp))
+ unregister_kretprobe(&tp->rp);
+ else
+ unregister_kprobe(&tp->rp.kp);
+ tp->flags &= ~TP_FLAG_REGISTERED;
+ /* Cleanup kprobe for reuse */
+ if (tp->rp.kp.symbol_name)
+ tp->rp.kp.addr = NULL;
+ }
+}
+
+/* Unregister a trace_probe and probe_event: call with locking probe_lock */
+static int unregister_trace_probe(struct trace_probe *tp)
+{
+ /* Enabled event can not be unregistered */
+ if (trace_probe_is_enabled(tp))
+ return -EBUSY;
+
+ __unregister_trace_probe(tp);
+ list_del(&tp->list);
+ unregister_probe_event(tp);
+
+ return 0;
+}
+
+/* Register a trace_probe and probe_event */
+static int register_trace_probe(struct trace_probe *tp)
+{
+ struct trace_probe *old_tp;
+ int ret;
+
+ mutex_lock(&probe_lock);
+
+ /* Delete old (same name) event if exist */
+ old_tp = find_trace_probe(tp->call.name, tp->call.class->system);
+ if (old_tp) {
+ ret = unregister_trace_probe(old_tp);
+ if (ret < 0)
+ goto end;
+ free_trace_probe(old_tp);
+ }
+
+ /* Register new event */
+ ret = register_probe_event(tp);
+ if (ret) {
+ pr_warning("Failed to register probe event(%d)\n", ret);
+ goto end;
+ }
+
+ /* Register k*probe */
+ ret = __register_trace_probe(tp);
+ if (ret < 0)
+ unregister_probe_event(tp);
+ else
+ list_add_tail(&tp->list, &probe_list);
+
+end:
+ mutex_unlock(&probe_lock);
+ return ret;
+}
+
+/* Module notifier call back, checking event on the module */
+static int trace_probe_module_callback(struct notifier_block *nb,
+ unsigned long val, void *data)
+{
+ struct module *mod = data;
+ struct trace_probe *tp;
+ int ret;
+
+ if (val != MODULE_STATE_COMING)
+ return NOTIFY_DONE;
+
+ /* Update probes on coming module */
+ mutex_lock(&probe_lock);
+ list_for_each_entry(tp, &probe_list, list) {
+ if (trace_probe_within_module(tp, mod)) {
+ /* Don't need to check busy - this should have gone. */
+ __unregister_trace_probe(tp);
+ ret = __register_trace_probe(tp);
+ if (ret)
+ pr_warning("Failed to re-register probe %s on"
+ "%s: %d\n",
+ tp->call.name, mod->name, ret);
+ }
+ }
+ mutex_unlock(&probe_lock);
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block trace_probe_module_nb = {
+ .notifier_call = trace_probe_module_callback,
+ .priority = 1 /* Invoked after kprobe module callback */
+};
+
+/* Split symbol and offset. */
+static int split_symbol_offset(char *symbol, unsigned long *offset)
+{
+ char *tmp;
+ int ret;
+
+ if (!offset)
+ return -EINVAL;
+
+ tmp = strchr(symbol, '+');
+ if (tmp) {
+ /* skip sign because strict_strtol doesn't accept '+' */
+ ret = strict_strtoul(tmp + 1, 0, offset);
+ if (ret)
+ return ret;
+ *tmp = '\0';
+ } else
+ *offset = 0;
+ return 0;
+}
+
+#define PARAM_MAX_ARGS 16
+#define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long))
+
+static int parse_probe_vars(char *arg, const struct fetch_type *t,
+ struct fetch_param *f, int is_return)
+{
+ int ret = 0;
+ unsigned long param;
+
+ if (strcmp(arg, "retval") == 0) {
+ if (is_return)
+ f->fn = t->fetch[FETCH_MTD_retval];
+ else
+ ret = -EINVAL;
+ } else if (strncmp(arg, "stack", 5) == 0) {
+ if (arg[5] == '\0') {
+ if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0)
+ f->fn = fetch_stack_address;
+ else
+ ret = -EINVAL;
+ } else if (isdigit(arg[5])) {
+ ret = strict_strtoul(arg + 5, 10, ¶m);
+ if (ret || param > PARAM_MAX_STACK)
+ ret = -EINVAL;
+ else {
+ f->fn = t->fetch[FETCH_MTD_stack];
+ f->data = (void *)param;
+ }
+ } else
+ ret = -EINVAL;
+ } else
+ ret = -EINVAL;
+ return ret;
+}
+
+/* Recursive argument parser */
+static int __parse_probe_arg(char *arg, const struct fetch_type *t,
+ struct fetch_param *f, int is_return)
+{
+ int ret = 0;
+ unsigned long param;
+ long offset;
+ char *tmp;
+
+ switch (arg[0]) {
+ case '$':
+ ret = parse_probe_vars(arg + 1, t, f, is_return);
+ break;
+ case '%': /* named register */
+ ret = regs_query_register_offset(arg + 1);
+ if (ret >= 0) {
+ f->fn = t->fetch[FETCH_MTD_reg];
+ f->data = (void *)(unsigned long)ret;
+ ret = 0;
+ }
+ break;
+ case '@': /* memory or symbol */
+ if (isdigit(arg[1])) {
+ ret = strict_strtoul(arg + 1, 0, ¶m);
+ if (ret)
+ break;
+ f->fn = t->fetch[FETCH_MTD_memory];
+ f->data = (void *)param;
+ } else {
+ ret = split_symbol_offset(arg + 1, &offset);
+ if (ret)
+ break;
+ f->data = alloc_symbol_cache(arg + 1, offset);
+ if (f->data)
+ f->fn = t->fetch[FETCH_MTD_symbol];
+ }
+ break;
+ case '+': /* deref memory */
+ arg++; /* Skip '+', because strict_strtol() rejects it. */
+ case '-':
+ tmp = strchr(arg, '(');
+ if (!tmp)
+ break;
+ *tmp = '\0';
+ ret = strict_strtol(arg, 0, &offset);
+ if (ret)
+ break;
+ arg = tmp + 1;
+ tmp = strrchr(arg, ')');
+ if (tmp) {
+ struct deref_fetch_param *dprm;
+ const struct fetch_type *t2 = find_fetch_type(NULL);
+ *tmp = '\0';
+ dprm = kzalloc(sizeof(struct deref_fetch_param),
+ GFP_KERNEL);
+ if (!dprm)
+ return -ENOMEM;
+ dprm->offset = offset;
+ ret = __parse_probe_arg(arg, t2, &dprm->orig,
+ is_return);
+ if (ret)
+ kfree(dprm);
+ else {
+ f->fn = t->fetch[FETCH_MTD_deref];
+ f->data = (void *)dprm;
+ }
+ }
+ break;
+ }
+ if (!ret && !f->fn) { /* Parsed, but do not find fetch method */
+ pr_info("%s type has no corresponding fetch method.\n",
+ t->name);
+ 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_param *f)
+{
+ struct bitfield_fetch_param *bprm;
+ unsigned long bw, bo;
+ char *tail;
+
+ if (*bf != 'b')
+ return 0;
+
+ bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
+ if (!bprm)
+ return -ENOMEM;
+ bprm->orig = *f;
+ f->fn = t->fetch[FETCH_MTD_bitfield];
+ f->data = (void *)bprm;
+
+ 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;
+
+ bprm->hi_shift = BYTES_TO_BITS(t->size) - (bw + bo);
+ bprm->low_shift = bprm->hi_shift + bo;
+ return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0;
+}
+
+/* String length checking wrapper */
+static int parse_probe_arg(char *arg, struct trace_probe *tp,
+ struct probe_arg *parg, int is_return)
+{
+ const char *t;
+ int ret;
+
+ if (strlen(arg) > MAX_ARGSTR_LEN) {
+ pr_info("Argument is too long.: %s\n", arg);
+ return -ENOSPC;
+ }
+ parg->comm = kstrdup(arg, GFP_KERNEL);
+ if (!parg->comm) {
+ pr_info("Failed to allocate memory for command '%s'.\n", arg);
+ return -ENOMEM;
+ }
+ t = strchr(parg->comm, ':');
+ if (t) {
+ arg[t - parg->comm] = '\0';
+ t++;
+ }
+ parg->type = find_fetch_type(t);
+ if (!parg->type) {
+ pr_info("Unsupported type: %s\n", t);
+ return -EINVAL;
+ }
+ parg->offset = tp->size;
+ tp->size += parg->type->size;
+ ret = __parse_probe_arg(arg, parg->type, &parg->fetch, is_return);
+ if (ret >= 0 && t != NULL)
+ ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch);
+ if (ret >= 0) {
+ parg->fetch_size.fn = get_fetch_size_function(parg->type,
+ parg->fetch.fn);
+ parg->fetch_size.data = parg->fetch.data;
+ }
+ return ret;
+}
+
+/* Return 1 if name is reserved or already used by another argument */
+static int 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;
+}
+
+static int create_trace_probe(int argc, char **argv)
+{
+ /*
+ * Argument syntax:
+ * - Add kprobe: p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS]
+ * - Add kretprobe: r[:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS]
+ * Fetch args:
+ * $retval : fetch return value
+ * $stack : fetch stack address
+ * $stackN : fetch Nth of stack (N:0-)
+ * @ADDR : fetch memory at ADDR (ADDR should be in kernel)
+ * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol)
+ * %REG : fetch register REG
+ * Dereferencing memory fetch:
+ * +|-offs(ARG) : fetch memory at ARG +|- offs address.
+ * Alias name of args:
+ * NAME=FETCHARG : set NAME as alias of FETCHARG.
+ * Type of args:
+ * FETCHARG:TYPE : use TYPE instead of unsigned long.
+ */
+ struct trace_probe *tp;
+ int i, ret = 0;
+ int is_return = 0, is_delete = 0;
+ char *symbol = NULL, *event = NULL, *group = NULL;
+ char *arg;
+ unsigned long offset = 0;
+ void *addr = NULL;
+ char buf[MAX_EVENT_NAME_LEN];
+
+ /* argc must be >= 1 */
+ if (argv[0][0] == 'p')
+ is_return = 0;
+ else if (argv[0][0] == 'r')
+ is_return = 1;
+ else if (argv[0][0] == '-')
+ is_delete = 1;
+ else {
+ pr_info("Probe definition must be started with 'p', 'r' or"
+ " '-'.\n");
+ return -EINVAL;
+ }
+
+ if (argv[0][1] == ':') {
+ event = &argv[0][2];
+ if (strchr(event, '/')) {
+ group = event;
+ event = strchr(group, '/') + 1;
+ event[-1] = '\0';
+ if (strlen(group) == 0) {
+ pr_info("Group name is not specified\n");
+ return -EINVAL;
+ }
+ }
+ if (strlen(event) == 0) {
+ pr_info("Event name is not specified\n");
+ return -EINVAL;
+ }
+ }
+ if (!group)
+ group = KPROBE_EVENT_SYSTEM;
+
+ if (is_delete) {
+ if (!event) {
+ pr_info("Delete command needs an event name.\n");
+ return -EINVAL;
+ }
+ mutex_lock(&probe_lock);
+ tp = find_trace_probe(event, group);
+ if (!tp) {
+ mutex_unlock(&probe_lock);
+ pr_info("Event %s/%s doesn't exist.\n", group, event);
+ return -ENOENT;
+ }
+ /* delete an event */
+ ret = unregister_trace_probe(tp);
+ if (ret == 0)
+ free_trace_probe(tp);
+ mutex_unlock(&probe_lock);
+ return ret;
+ }
+
+ if (argc < 2) {
+ pr_info("Probe point is not specified.\n");
+ return -EINVAL;
+ }
+ if (isdigit(argv[1][0])) {
+ if (is_return) {
+ pr_info("Return probe point must be a symbol.\n");
+ return -EINVAL;
+ }
+ /* an address specified */
+ ret = strict_strtoul(&argv[1][0], 0, (unsigned long *)&addr);
+ if (ret) {
+ pr_info("Failed to parse address.\n");
+ return ret;
+ }
+ } else {
+ /* a symbol specified */
+ symbol = argv[1];
+ /* TODO: support .init module functions */
+ ret = split_symbol_offset(symbol, &offset);
+ if (ret) {
+ pr_info("Failed to parse symbol.\n");
+ return ret;
+ }
+ if (offset && is_return) {
+ pr_info("Return probe must be used without offset.\n");
+ return -EINVAL;
+ }
+ }
+ argc -= 2; argv += 2;
+
+ /* setup a probe */
+ if (!event) {
+ /* Make a new event name */
+ if (symbol)
+ snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld",
+ is_return ? 'r' : 'p', symbol, offset);
+ else
+ snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p",
+ is_return ? 'r' : 'p', addr);
+ event = buf;
+ }
+ tp = alloc_trace_probe(group, event, addr, symbol, offset, argc,
+ is_return);
+ if (IS_ERR(tp)) {
+ pr_info("Failed to allocate trace_probe.(%d)\n",
+ (int)PTR_ERR(tp));
+ return PTR_ERR(tp);
+ }
+
+ /* parse arguments */
+ ret = 0;
+ for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
+ /* Increment count for freeing args in error case */
+ tp->nr_args++;
+
+ /* Parse argument name */
+ arg = strchr(argv[i], '=');
+ if (arg) {
+ *arg++ = '\0';
+ tp->args[i].name = kstrdup(argv[i], GFP_KERNEL);
+ } else {
+ arg = argv[i];
+ /* If argument name is omitted, set "argN" */
+ snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1);
+ tp->args[i].name = kstrdup(buf, GFP_KERNEL);
+ }
+
+ if (!tp->args[i].name) {
+ pr_info("Failed to allocate argument[%d] name.\n", i);
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ if (!is_good_name(tp->args[i].name)) {
+ pr_info("Invalid argument[%d] name: %s\n",
+ i, tp->args[i].name);
+ ret = -EINVAL;
+ goto error;
+ }
+
+ if (conflict_field_name(tp->args[i].name, tp->args, i)) {
+ pr_info("Argument[%d] name '%s' conflicts with "
+ "another field.\n", i, argv[i]);
+ ret = -EINVAL;
+ goto error;
+ }
+
+ /* Parse fetch argument */
+ ret = parse_probe_arg(arg, tp, &tp->args[i], is_return);
+ if (ret) {
+ pr_info("Parse error at argument[%d]. (%d)\n", i, ret);
+ goto error;
+ }
+ }
+
+ ret = register_trace_probe(tp);
+ if (ret)
+ goto error;
+ return 0;
+
+error:
+ free_trace_probe(tp);
+ return ret;
+}
+
+static int release_all_trace_probes(void)
+{
+ struct trace_probe *tp;
+ int ret = 0;
+
+ mutex_lock(&probe_lock);
+ /* Ensure no probe is in use. */
+ list_for_each_entry(tp, &probe_list, list)
+ if (trace_probe_is_enabled(tp)) {
+ ret = -EBUSY;
+ goto end;
+ }
+ /* TODO: Use batch unregistration */
+ while (!list_empty(&probe_list)) {
+ tp = list_entry(probe_list.next, struct trace_probe, list);
+ unregister_trace_probe(tp);
+ free_trace_probe(tp);
+ }
+
+end:
+ mutex_unlock(&probe_lock);
+
+ return ret;
+}
+
+/* Probes listing interfaces */
+static void *probes_seq_start(struct seq_file *m, loff_t *pos)
+{
+ mutex_lock(&probe_lock);
+ return seq_list_start(&probe_list, *pos);
+}
+
+static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ return seq_list_next(v, &probe_list, pos);
+}
+
+static void probes_seq_stop(struct seq_file *m, void *v)
+{
+ mutex_unlock(&probe_lock);
+}
+
+static int probes_seq_show(struct seq_file *m, void *v)
+{
+ struct trace_probe *tp = v;
+ int i;
+
+ seq_printf(m, "%c", trace_probe_is_return(tp) ? 'r' : 'p');
+ seq_printf(m, ":%s/%s", tp->call.class->system, tp->call.name);
+
+ if (!tp->symbol)
+ seq_printf(m, " 0x%p", tp->rp.kp.addr);
+ else if (tp->rp.kp.offset)
+ seq_printf(m, " %s+%u", trace_probe_symbol(tp),
+ tp->rp.kp.offset);
+ else
+ seq_printf(m, " %s", trace_probe_symbol(tp));
+
+ for (i = 0; i < tp->nr_args; i++)
+ seq_printf(m, " %s=%s", tp->args[i].name, tp->args[i].comm);
+ seq_printf(m, "\n");
+
+ return 0;
+}
+
+static const struct seq_operations probes_seq_op = {
+ .start = probes_seq_start,
+ .next = probes_seq_next,
+ .stop = probes_seq_stop,
+ .show = probes_seq_show
+};
+
+static int probes_open(struct inode *inode, struct file *file)
+{
+ int ret;
+
+ if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
+ ret = release_all_trace_probes();
+ if (ret < 0)
+ return ret;
+ }
+
+ return seq_open(file, &probes_seq_op);
+}
+
+static int command_trace_probe(const char *buf)
+{
+ char **argv;
+ int argc = 0, ret = 0;
+
+ argv = argv_split(GFP_KERNEL, buf, &argc);
+ if (!argv)
+ return -ENOMEM;
+
+ if (argc)
+ ret = create_trace_probe(argc, argv);
+
+ argv_free(argv);
+ return ret;
+}
+
+#define WRITE_BUFSIZE 4096
+
+static ssize_t probes_write(struct file *file, const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ char *kbuf, *tmp;
+ int ret;
+ size_t done;
+ size_t size;
+
+ kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL);
+ if (!kbuf)
+ return -ENOMEM;
+
+ ret = done = 0;
+ while (done < count) {
+ size = count - done;
+ if (size >= WRITE_BUFSIZE)
+ size = WRITE_BUFSIZE - 1;
+ if (copy_from_user(kbuf, buffer + done, size)) {
+ ret = -EFAULT;
+ goto out;
+ }
+ kbuf[size] = '\0';
+ tmp = strchr(kbuf, '\n');
+ if (tmp) {
+ *tmp = '\0';
+ size = tmp - kbuf + 1;
+ } else if (done + size < count) {
+ pr_warning("Line length is too long: "
+ "Should be less than %d.", WRITE_BUFSIZE);
+ ret = -EINVAL;
+ goto out;
+ }
+ done += size;
+ /* Remove comments */
+ tmp = strchr(kbuf, '#');
+ if (tmp)
+ *tmp = '\0';
+
+ ret = command_trace_probe(kbuf);
+ if (ret)
+ goto out;
+ }
+ ret = done;
+out:
+ kfree(kbuf);
+ return ret;
+}
+
+static const struct file_operations kprobe_events_ops = {
+ .owner = THIS_MODULE,
+ .open = probes_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+ .write = probes_write,
+};
+
+/* Probes profiling interfaces */
+static int probes_profile_seq_show(struct seq_file *m, void *v)
+{
+ struct trace_probe *tp = v;
+
+ seq_printf(m, " %-44s %15lu %15lu\n", tp->call.name, tp->nhit,
+ tp->rp.kp.nmissed);
+
+ return 0;
+}
+
+static const struct seq_operations profile_seq_op = {
+ .start = probes_seq_start,
+ .next = probes_seq_next,
+ .stop = probes_seq_stop,
+ .show = probes_profile_seq_show
+};
+
+static int profile_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &profile_seq_op);
+}
+
+static const struct file_operations kprobe_profile_ops = {
+ .owner = THIS_MODULE,
+ .open = profile_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+/* Sum up total data length for dynamic arraies (strings) */
+static __kprobes int __get_data_size(struct trace_probe *tp,
+ struct pt_regs *regs)
+{
+ int i, ret = 0;
+ u32 len;
+
+ for (i = 0; i < tp->nr_args; i++)
+ if (unlikely(tp->args[i].fetch_size.fn)) {
+ call_fetch(&tp->args[i].fetch_size, regs, &len);
+ ret += len;
+ }
+
+ return ret;
+}
+
+/* Store the value of each argument */
+static __kprobes void store_trace_args(int ent_size, struct trace_probe *tp,
+ struct pt_regs *regs,
+ u8 *data, int maxlen)
+{
+ int i;
+ u32 end = tp->size;
+ u32 *dl; /* Data (relative) location */
+
+ for (i = 0; i < tp->nr_args; i++) {
+ if (unlikely(tp->args[i].fetch_size.fn)) {
+ /*
+ * First, we set the relative location and
+ * maximum data length to *dl
+ */
+ dl = (u32 *)(data + tp->args[i].offset);
+ *dl = make_data_rloc(maxlen, end - tp->args[i].offset);
+ /* Then try to fetch string or dynamic array data */
+ call_fetch(&tp->args[i].fetch, regs, dl);
+ /* Reduce maximum length */
+ end += get_rloc_len(*dl);
+ maxlen -= get_rloc_len(*dl);
+ /* Trick here, convert data_rloc to data_loc */
+ *dl = convert_rloc_to_loc(*dl,
+ ent_size + tp->args[i].offset);
+ } else
+ /* Just fetching data normally */
+ call_fetch(&tp->args[i].fetch, regs,
+ data + tp->args[i].offset);
+ }
+}
+
+/* Kprobe handler */
+static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs)
+{
+ struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
+ struct kprobe_trace_entry_head *entry;
+ struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
+ int size, dsize, pc;
+ unsigned long irq_flags;
+ struct ftrace_event_call *call = &tp->call;
+
+ tp->nhit++;
+
+ local_save_flags(irq_flags);
+ pc = preempt_count();
+
+ dsize = __get_data_size(tp, regs);
+ size = sizeof(*entry) + tp->size + dsize;
+
+ event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
+ size, irq_flags, pc);
+ if (!event)
+ return;
+
+ entry = ring_buffer_event_data(event);
+ entry->ip = (unsigned long)kp->addr;
+ store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
+
+ if (!filter_current_check_discard(buffer, call, entry, event))
+ trace_nowake_buffer_unlock_commit_regs(buffer, event,
+ irq_flags, pc, regs);
+}
+
+/* Kretprobe handler */
+static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri,
+ struct pt_regs *regs)
+{
+ struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
+ struct kretprobe_trace_entry_head *entry;
+ struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
+ int size, pc, dsize;
+ unsigned long irq_flags;
+ struct ftrace_event_call *call = &tp->call;
+
+ local_save_flags(irq_flags);
+ pc = preempt_count();
+
+ dsize = __get_data_size(tp, regs);
+ size = sizeof(*entry) + tp->size + dsize;
+
+ event = trace_current_buffer_lock_reserve(&buffer, call->event.type,
+ size, irq_flags, pc);
+ if (!event)
+ return;
+
+ entry = ring_buffer_event_data(event);
+ entry->func = (unsigned long)tp->rp.kp.addr;
+ entry->ret_ip = (unsigned long)ri->ret_addr;
+ store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
+
+ if (!filter_current_check_discard(buffer, call, entry, event))
+ trace_nowake_buffer_unlock_commit_regs(buffer, event,
+ irq_flags, pc, regs);
+}
+
+/* Event entry printers */
+enum print_line_t
+print_kprobe_event(struct trace_iterator *iter, int flags,
+ struct trace_event *event)
+{
+ struct kprobe_trace_entry_head *field;
+ struct trace_seq *s = &iter->seq;
+ struct trace_probe *tp;
+ u8 *data;
+ int i;
+
+ field = (struct kprobe_trace_entry_head *)iter->ent;
+ tp = container_of(event, struct trace_probe, call.event);
+
+ if (!trace_seq_printf(s, "%s: (", tp->call.name))
+ goto partial;
+
+ if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET))
+ goto partial;
+
+ if (!trace_seq_puts(s, ")"))
+ goto partial;
+
+ data = (u8 *)&field[1];
+ for (i = 0; i < tp->nr_args; i++)
+ if (!tp->args[i].type->print(s, tp->args[i].name,
+ data + tp->args[i].offset, field))
+ goto partial;
+
+ if (!trace_seq_puts(s, "\n"))
+ goto partial;
+
+ return TRACE_TYPE_HANDLED;
+partial:
+ return TRACE_TYPE_PARTIAL_LINE;
+}
+
+enum print_line_t
+print_kretprobe_event(struct trace_iterator *iter, int flags,
+ struct trace_event *event)
+{
+ struct kretprobe_trace_entry_head *field;
+ struct trace_seq *s = &iter->seq;
+ struct trace_probe *tp;
+ u8 *data;
+ int i;
+
+ field = (struct kretprobe_trace_entry_head *)iter->ent;
+ tp = container_of(event, struct trace_probe, call.event);
+
+ if (!trace_seq_printf(s, "%s: (", tp->call.name))
+ goto partial;
+
+ if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET))
+ goto partial;
+
+ if (!trace_seq_puts(s, " <- "))
+ goto partial;
+
+ if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET))
+ goto partial;
+
+ if (!trace_seq_puts(s, ")"))
+ goto partial;
+
+ data = (u8 *)&field[1];
+ for (i = 0; i < tp->nr_args; i++)
+ if (!tp->args[i].type->print(s, tp->args[i].name,
+ data + tp->args[i].offset, field))
+ goto partial;
+
+ if (!trace_seq_puts(s, "\n"))
+ goto partial;
+
+ return TRACE_TYPE_HANDLED;
+partial:
+ return TRACE_TYPE_PARTIAL_LINE;
+}
+
+#undef DEFINE_FIELD
+#define DEFINE_FIELD(type, item, name, is_signed) \
+ do { \
+ ret = trace_define_field(event_call, #type, name, \
+ offsetof(typeof(field), item), \
+ sizeof(field.item), is_signed, \
+ FILTER_OTHER); \
+ if (ret) \
+ return ret; \
+ } while (0)
+
+static int kprobe_event_define_fields(struct ftrace_event_call *event_call)
+{
+ int ret, i;
+ struct kprobe_trace_entry_head field;
+ struct trace_probe *tp = (struct trace_probe *)event_call->data;
+
+ DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0);
+ /* Set argument names as fields */
+ for (i = 0; i < tp->nr_args; i++) {
+ ret = trace_define_field(event_call, tp->args[i].type->fmttype,
+ tp->args[i].name,
+ sizeof(field) + tp->args[i].offset,
+ tp->args[i].type->size,
+ tp->args[i].type->is_signed,
+ FILTER_OTHER);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+static int kretprobe_event_define_fields(struct ftrace_event_call *event_call)
+{
+ int ret, i;
+ struct kretprobe_trace_entry_head field;
+ struct trace_probe *tp = (struct trace_probe *)event_call->data;
+
+ DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0);
+ DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0);
+ /* Set argument names as fields */
+ for (i = 0; i < tp->nr_args; i++) {
+ ret = trace_define_field(event_call, tp->args[i].type->fmttype,
+ tp->args[i].name,
+ sizeof(field) + tp->args[i].offset,
+ tp->args[i].type->size,
+ tp->args[i].type->is_signed,
+ FILTER_OTHER);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+static int __set_print_fmt(struct trace_probe *tp, char *buf, int len)
+{
+ int i;
+ int pos = 0;
+
+ const char *fmt, *arg;
+
+ if (!trace_probe_is_return(tp)) {
+ fmt = "(%lx)";
+ arg = "REC->" FIELD_STRING_IP;
+ } else {
+ fmt = "(%lx <- %lx)";
+ arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP;
+ }
+
+ /* When len=0, we just calculate the needed length */
+#define LEN_OR_ZERO (len ? len - pos : 0)
+
+ pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt);
+
+ for (i = 0; i < tp->nr_args; i++) {
+ pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s",
+ tp->args[i].name, tp->args[i].type->fmt);
+ }
+
+ pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg);
+
+ for (i = 0; i < tp->nr_args; i++) {
+ if (strcmp(tp->args[i].type->name, "string") == 0)
+ pos += snprintf(buf + pos, LEN_OR_ZERO,
+ ", __get_str(%s)",
+ tp->args[i].name);
+ else
+ pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s",
+ tp->args[i].name);
+ }
+
+#undef LEN_OR_ZERO
+
+ /* return the length of print_fmt */
+ return pos;
+}
+
+static int set_print_fmt(struct trace_probe *tp)
+{
+ int len;
+ char *print_fmt;
+
+ /* First: called with 0 length to calculate the needed length */
+ len = __set_print_fmt(tp, NULL, 0);
+ 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);
+ tp->call.print_fmt = print_fmt;
+
+ return 0;
+}
+
+#ifdef CONFIG_PERF_EVENTS
+
+/* Kprobe profile handler */
+static __kprobes void kprobe_perf_func(struct kprobe *kp,
+ struct pt_regs *regs)
+{
+ struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
+ struct ftrace_event_call *call = &tp->call;
+ struct kprobe_trace_entry_head *entry;
+ struct hlist_head *head;
+ int size, __size, dsize;
+ int rctx;
+
+ dsize = __get_data_size(tp, regs);
+ __size = sizeof(*entry) + tp->size + dsize;
+ size = ALIGN(__size + sizeof(u32), sizeof(u64));
+ size -= sizeof(u32);
+ if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
+ "profile buffer not large enough"))
+ return;
+
+ entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
+ if (!entry)
+ return;
+
+ entry->ip = (unsigned long)kp->addr;
+ memset(&entry[1], 0, dsize);
+ store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
+
+ head = this_cpu_ptr(call->perf_events);
+ perf_trace_buf_submit(entry, size, rctx, entry->ip, 1, regs, head);
+}
+
+/* Kretprobe profile handler */
+static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri,
+ struct pt_regs *regs)
+{
+ struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
+ struct ftrace_event_call *call = &tp->call;
+ struct kretprobe_trace_entry_head *entry;
+ struct hlist_head *head;
+ int size, __size, dsize;
+ int rctx;
+
+ dsize = __get_data_size(tp, regs);
+ __size = sizeof(*entry) + tp->size + dsize;
+ size = ALIGN(__size + sizeof(u32), sizeof(u64));
+ size -= sizeof(u32);
+ if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE,
+ "profile buffer not large enough"))
+ return;
+
+ entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx);
+ if (!entry)
+ return;
+
+ entry->func = (unsigned long)tp->rp.kp.addr;
+ entry->ret_ip = (unsigned long)ri->ret_addr;
+ store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize);
+
+ head = this_cpu_ptr(call->perf_events);
+ perf_trace_buf_submit(entry, size, rctx, entry->ret_ip, 1, regs, head);
+}
+#endif /* CONFIG_PERF_EVENTS */
+
+static __kprobes
+int kprobe_register(struct ftrace_event_call *event,
+ enum trace_reg type, void *data)
+{
+ struct trace_probe *tp = (struct trace_probe *)event->data;
+
+ switch (type) {
+ case TRACE_REG_REGISTER:
+ return enable_trace_probe(tp, TP_FLAG_TRACE);
+ case TRACE_REG_UNREGISTER:
+ disable_trace_probe(tp, TP_FLAG_TRACE);
+ return 0;
+
+#ifdef CONFIG_PERF_EVENTS
+ case TRACE_REG_PERF_REGISTER:
+ return enable_trace_probe(tp, TP_FLAG_PROFILE);
+ case TRACE_REG_PERF_UNREGISTER:
+ disable_trace_probe(tp, TP_FLAG_PROFILE);
+ return 0;
+ case TRACE_REG_PERF_OPEN:
+ case TRACE_REG_PERF_CLOSE:
+ case TRACE_REG_PERF_ADD:
+ case TRACE_REG_PERF_DEL:
+ return 0;
+#endif
+ }
+ return 0;
+}
+
+static __kprobes
+int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs)
+{
+ struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp);
+
+ if (tp->flags & TP_FLAG_TRACE)
+ kprobe_trace_func(kp, regs);
+#ifdef CONFIG_PERF_EVENTS
+ if (tp->flags & TP_FLAG_PROFILE)
+ kprobe_perf_func(kp, regs);
+#endif
+ return 0; /* We don't tweek kernel, so just return 0 */
+}
+
+static __kprobes
+int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs)
+{
+ struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp);
+
+ if (tp->flags & TP_FLAG_TRACE)
+ kretprobe_trace_func(ri, regs);
+#ifdef CONFIG_PERF_EVENTS
+ if (tp->flags & TP_FLAG_PROFILE)
+ kretprobe_perf_func(ri, regs);
+#endif
+ return 0; /* We don't tweek kernel, so just return 0 */
+}
+
+static struct trace_event_functions kretprobe_funcs = {
+ .trace = print_kretprobe_event
+};
+
+static struct trace_event_functions kprobe_funcs = {
+ .trace = print_kprobe_event
+};
+
+static int register_probe_event(struct trace_probe *tp)
+{
+ struct ftrace_event_call *call = &tp->call;
+ int ret;
+
+ /* Initialize ftrace_event_call */
+ INIT_LIST_HEAD(&call->class->fields);
+ if (trace_probe_is_return(tp)) {
+ call->event.funcs = &kretprobe_funcs;
+ call->class->define_fields = kretprobe_event_define_fields;
+ } else {
+ call->event.funcs = &kprobe_funcs;
+ call->class->define_fields = kprobe_event_define_fields;
+ }
+ if (set_print_fmt(tp) < 0)
+ return -ENOMEM;
+ ret = register_ftrace_event(&call->event);
+ if (!ret) {
+ kfree(call->print_fmt);
+ return -ENODEV;
+ }
+ call->flags = 0;
+ call->class->reg = kprobe_register;
+ call->data = tp;
+ ret = trace_add_event_call(call);
+ if (ret) {
+ pr_info("Failed to register kprobe event: %s\n", call->name);
+ kfree(call->print_fmt);
+ unregister_ftrace_event(&call->event);
+ }
+ return ret;
+}
+
+static void unregister_probe_event(struct trace_probe *tp)
+{
+ /* tp->event is unregistered in trace_remove_event_call() */
+ trace_remove_event_call(&tp->call);
+ kfree(tp->call.print_fmt);
+}
+
+/* Make a debugfs interface for controlling probe points */
+static __init int init_kprobe_trace(void)
+{
+ struct dentry *d_tracer;
+ struct dentry *entry;
+
+ if (register_module_notifier(&trace_probe_module_nb))
+ return -EINVAL;
+
+ d_tracer = tracing_init_dentry();
+ if (!d_tracer)
+ return 0;
+
+ entry = debugfs_create_file("kprobe_events", 0644, d_tracer,
+ NULL, &kprobe_events_ops);
+
+ /* Event list interface */
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'kprobe_events' entry\n");
+
+ /* Profile interface */
+ entry = debugfs_create_file("kprobe_profile", 0444, d_tracer,
+ NULL, &kprobe_profile_ops);
+
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'kprobe_profile' entry\n");
+ return 0;
+}
+fs_initcall(init_kprobe_trace);
+
+
+#ifdef CONFIG_FTRACE_STARTUP_TEST
+
+/*
+ * The "__used" keeps gcc from removing the function symbol
+ * from the kallsyms table.
+ */
+static __used int kprobe_trace_selftest_target(int a1, int a2, int a3,
+ int a4, int a5, int a6)
+{
+ return a1 + a2 + a3 + a4 + a5 + a6;
+}
+
+static __init int kprobe_trace_self_tests_init(void)
+{
+ int ret, warn = 0;
+ int (*target)(int, int, int, int, int, int);
+ struct trace_probe *tp;
+
+ target = kprobe_trace_selftest_target;
+
+ pr_info("Testing kprobe tracing: ");
+
+ ret = command_trace_probe("p:testprobe kprobe_trace_selftest_target "
+ "$stack $stack0 +0($stack)");
+ if (WARN_ON_ONCE(ret)) {
+ pr_warning("error on probing function entry.\n");
+ warn++;
+ } else {
+ /* Enable trace point */
+ tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM);
+ if (WARN_ON_ONCE(tp == NULL)) {
+ pr_warning("error on getting new probe.\n");
+ warn++;
+ } else
+ enable_trace_probe(tp, TP_FLAG_TRACE);
+ }
+
+ ret = command_trace_probe("r:testprobe2 kprobe_trace_selftest_target "
+ "$retval");
+ if (WARN_ON_ONCE(ret)) {
+ pr_warning("error on probing function return.\n");
+ warn++;
+ } else {
+ /* Enable trace point */
+ tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM);
+ if (WARN_ON_ONCE(tp == NULL)) {
+ pr_warning("error on getting new probe.\n");
+ warn++;
+ } else
+ enable_trace_probe(tp, TP_FLAG_TRACE);
+ }
+
+ if (warn)
+ goto end;
+
+ ret = target(1, 2, 3, 4, 5, 6);
+
+ /* Disable trace points before removing it */
+ tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM);
+ if (WARN_ON_ONCE(tp == NULL)) {
+ pr_warning("error on getting test probe.\n");
+ warn++;
+ } else
+ disable_trace_probe(tp, TP_FLAG_TRACE);
+
+ tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM);
+ if (WARN_ON_ONCE(tp == NULL)) {
+ pr_warning("error on getting 2nd test probe.\n");
+ warn++;
+ } else
+ disable_trace_probe(tp, TP_FLAG_TRACE);
+
+ ret = command_trace_probe("-:testprobe");
+ if (WARN_ON_ONCE(ret)) {
+ pr_warning("error on deleting a probe.\n");
+ warn++;
+ }
+
+ ret = command_trace_probe("-:testprobe2");
+ if (WARN_ON_ONCE(ret)) {
+ pr_warning("error on deleting a probe.\n");
+ warn++;
+ }
+
+end:
+ release_all_trace_probes();
+ if (warn)
+ pr_cont("NG: Some tests are failed. Please check them.\n");
+ else
+ pr_cont("OK\n");
+ return 0;
+}
+
+late_initcall(kprobe_trace_self_tests_init);
+
+#endif