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-rw-r--r--kernel/trace/trace_probe.h459
1 files changed, 459 insertions, 0 deletions
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
new file mode 100644
index 000000000..d4a69b839
--- /dev/null
+++ b/kernel/trace/trace_probe.h
@@ -0,0 +1,459 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Common header file for probe-based Dynamic events.
+ *
+ * This code was copied from kernel/trace/trace_kprobe.h written by
+ * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
+ *
+ * Updates to make this generic:
+ * Copyright (C) IBM Corporation, 2010-2011
+ * Author: Srikar Dronamraju
+ */
+
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/smp.h>
+#include <linux/tracefs.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/ptrace.h>
+#include <linux/perf_event.h>
+#include <linux/kprobes.h>
+#include <linux/stringify.h>
+#include <linux/limits.h>
+#include <linux/uaccess.h>
+#include <linux/bitops.h>
+#include <asm/bitsperlong.h>
+
+#include "trace.h"
+#include "trace_output.h"
+
+#define MAX_TRACE_ARGS 128
+#define MAX_ARGSTR_LEN 63
+#define MAX_ARRAY_LEN 64
+#define MAX_ARG_NAME_LEN 32
+#define MAX_STRING_SIZE PATH_MAX
+
+/* Reserved field names */
+#define FIELD_STRING_IP "__probe_ip"
+#define FIELD_STRING_RETIP "__probe_ret_ip"
+#define FIELD_STRING_FUNC "__probe_func"
+
+#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)
+
+
+/* Flags for trace_probe */
+#define TP_FLAG_TRACE 1
+#define TP_FLAG_PROFILE 2
+
+/* data_loc: data location, compatible with u32 */
+#define make_data_loc(len, offs) \
+ (((u32)(len) << 16) | ((u32)(offs) & 0xffff))
+#define get_loc_len(dl) ((u32)(dl) >> 16)
+#define get_loc_offs(dl) ((u32)(dl) & 0xffff)
+
+static nokprobe_inline void *get_loc_data(u32 *dl, void *ent)
+{
+ return (u8 *)ent + get_loc_offs(*dl);
+}
+
+static nokprobe_inline u32 update_data_loc(u32 loc, int consumed)
+{
+ u32 maxlen = get_loc_len(loc);
+ u32 offset = get_loc_offs(loc);
+
+ return make_data_loc(maxlen - consumed, offset + consumed);
+}
+
+/* Printing function type */
+typedef int (*print_type_func_t)(struct trace_seq *, void *, void *);
+
+enum fetch_op {
+ FETCH_OP_NOP = 0,
+ // Stage 1 (load) ops
+ FETCH_OP_REG, /* Register : .param = offset */
+ FETCH_OP_STACK, /* Stack : .param = index */
+ FETCH_OP_STACKP, /* Stack pointer */
+ FETCH_OP_RETVAL, /* Return value */
+ FETCH_OP_IMM, /* Immediate : .immediate */
+ FETCH_OP_COMM, /* Current comm */
+ FETCH_OP_ARG, /* Function argument : .param */
+ FETCH_OP_FOFFS, /* File offset: .immediate */
+ FETCH_OP_DATA, /* Allocated data: .data */
+ // Stage 2 (dereference) op
+ FETCH_OP_DEREF, /* Dereference: .offset */
+ FETCH_OP_UDEREF, /* User-space Dereference: .offset */
+ // Stage 3 (store) ops
+ FETCH_OP_ST_RAW, /* Raw: .size */
+ FETCH_OP_ST_MEM, /* Mem: .offset, .size */
+ FETCH_OP_ST_UMEM, /* Mem: .offset, .size */
+ FETCH_OP_ST_STRING, /* String: .offset, .size */
+ FETCH_OP_ST_USTRING, /* User String: .offset, .size */
+ // Stage 4 (modify) op
+ FETCH_OP_MOD_BF, /* Bitfield: .basesize, .lshift, .rshift */
+ // Stage 5 (loop) op
+ FETCH_OP_LP_ARRAY, /* Array: .param = loop count */
+ FETCH_OP_END,
+ FETCH_NOP_SYMBOL, /* Unresolved Symbol holder */
+};
+
+struct fetch_insn {
+ enum fetch_op op;
+ union {
+ unsigned int param;
+ struct {
+ unsigned int size;
+ int offset;
+ };
+ struct {
+ unsigned char basesize;
+ unsigned char lshift;
+ unsigned char rshift;
+ };
+ unsigned long immediate;
+ void *data;
+ };
+};
+
+/* fetch + deref*N + store + mod + end <= 16, this allows N=12, enough */
+#define FETCH_INSN_MAX 16
+#define FETCH_TOKEN_COMM (-ECOMM)
+
+/* Fetch type information table */
+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 */
+};
+
+/* For defining macros, define string/string_size types */
+typedef u32 string;
+typedef u32 string_size;
+
+#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 DECLARE_BASIC_PRINT_TYPE_FUNC(type) \
+int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, void *data, void *ent);\
+extern const char PRINT_TYPE_FMT_NAME(type)[]
+
+DECLARE_BASIC_PRINT_TYPE_FUNC(u8);
+DECLARE_BASIC_PRINT_TYPE_FUNC(u16);
+DECLARE_BASIC_PRINT_TYPE_FUNC(u32);
+DECLARE_BASIC_PRINT_TYPE_FUNC(u64);
+DECLARE_BASIC_PRINT_TYPE_FUNC(s8);
+DECLARE_BASIC_PRINT_TYPE_FUNC(s16);
+DECLARE_BASIC_PRINT_TYPE_FUNC(s32);
+DECLARE_BASIC_PRINT_TYPE_FUNC(s64);
+DECLARE_BASIC_PRINT_TYPE_FUNC(x8);
+DECLARE_BASIC_PRINT_TYPE_FUNC(x16);
+DECLARE_BASIC_PRINT_TYPE_FUNC(x32);
+DECLARE_BASIC_PRINT_TYPE_FUNC(x64);
+
+DECLARE_BASIC_PRINT_TYPE_FUNC(string);
+DECLARE_BASIC_PRINT_TYPE_FUNC(symbol);
+
+/* Default (unsigned long) fetch type */
+#define __DEFAULT_FETCH_TYPE(t) x##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)
+
+#define __ADDR_FETCH_TYPE(t) u##t
+#define _ADDR_FETCH_TYPE(t) __ADDR_FETCH_TYPE(t)
+#define ADDR_FETCH_TYPE _ADDR_FETCH_TYPE(BITS_PER_LONG)
+
+#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, \
+ }
+#define _ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
+ __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, #_fmttype)
+#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \
+ _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, ptype)
+
+/* If ptype is an alias of atype, use this macro (show atype in format) */
+#define ASSIGN_FETCH_TYPE_ALIAS(ptype, atype, ftype, sign) \
+ _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, atype)
+
+#define ASSIGN_FETCH_TYPE_END {}
+#define MAX_ARRAY_LEN 64
+
+#ifdef CONFIG_KPROBE_EVENTS
+bool trace_kprobe_on_func_entry(struct trace_event_call *call);
+bool trace_kprobe_error_injectable(struct trace_event_call *call);
+#else
+static inline bool trace_kprobe_on_func_entry(struct trace_event_call *call)
+{
+ return false;
+}
+
+static inline bool trace_kprobe_error_injectable(struct trace_event_call *call)
+{
+ return false;
+}
+#endif /* CONFIG_KPROBE_EVENTS */
+
+struct probe_arg {
+ struct fetch_insn *code;
+ bool dynamic;/* Dynamic array (string) is used */
+ unsigned int offset; /* Offset from argument entry */
+ unsigned int count; /* Array count */
+ const char *name; /* Name of this argument */
+ const char *comm; /* Command of this argument */
+ char *fmt; /* Format string if needed */
+ const struct fetch_type *type; /* Type of this argument */
+};
+
+struct trace_uprobe_filter {
+ rwlock_t rwlock;
+ int nr_systemwide;
+ struct list_head perf_events;
+};
+
+/* Event call and class holder */
+struct trace_probe_event {
+ unsigned int flags; /* For TP_FLAG_* */
+ struct trace_event_class class;
+ struct trace_event_call call;
+ struct list_head files;
+ struct list_head probes;
+ struct trace_uprobe_filter filter[];
+};
+
+struct trace_probe {
+ struct list_head list;
+ struct trace_probe_event *event;
+ ssize_t size; /* trace entry size */
+ unsigned int nr_args;
+ struct probe_arg args[];
+};
+
+struct event_file_link {
+ struct trace_event_file *file;
+ struct list_head list;
+};
+
+static inline bool trace_probe_test_flag(struct trace_probe *tp,
+ unsigned int flag)
+{
+ return !!(tp->event->flags & flag);
+}
+
+static inline void trace_probe_set_flag(struct trace_probe *tp,
+ unsigned int flag)
+{
+ tp->event->flags |= flag;
+}
+
+static inline void trace_probe_clear_flag(struct trace_probe *tp,
+ unsigned int flag)
+{
+ tp->event->flags &= ~flag;
+}
+
+static inline bool trace_probe_is_enabled(struct trace_probe *tp)
+{
+ return trace_probe_test_flag(tp, TP_FLAG_TRACE | TP_FLAG_PROFILE);
+}
+
+static inline const char *trace_probe_name(struct trace_probe *tp)
+{
+ return trace_event_name(&tp->event->call);
+}
+
+static inline const char *trace_probe_group_name(struct trace_probe *tp)
+{
+ return tp->event->call.class->system;
+}
+
+static inline struct trace_event_call *
+ trace_probe_event_call(struct trace_probe *tp)
+{
+ return &tp->event->call;
+}
+
+static inline struct trace_probe_event *
+trace_probe_event_from_call(struct trace_event_call *event_call)
+{
+ return container_of(event_call, struct trace_probe_event, call);
+}
+
+static inline struct trace_probe *
+trace_probe_primary_from_call(struct trace_event_call *call)
+{
+ struct trace_probe_event *tpe = trace_probe_event_from_call(call);
+
+ return list_first_entry_or_null(&tpe->probes, struct trace_probe, list);
+}
+
+static inline struct list_head *trace_probe_probe_list(struct trace_probe *tp)
+{
+ return &tp->event->probes;
+}
+
+static inline bool trace_probe_has_sibling(struct trace_probe *tp)
+{
+ struct list_head *list = trace_probe_probe_list(tp);
+
+ return !list_empty(list) && !list_is_singular(list);
+}
+
+static inline int trace_probe_unregister_event_call(struct trace_probe *tp)
+{
+ /* tp->event is unregistered in trace_remove_event_call() */
+ return trace_remove_event_call(&tp->event->call);
+}
+
+static inline bool trace_probe_has_single_file(struct trace_probe *tp)
+{
+ return !!list_is_singular(&tp->event->files);
+}
+
+int trace_probe_init(struct trace_probe *tp, const char *event,
+ const char *group, bool alloc_filter);
+void trace_probe_cleanup(struct trace_probe *tp);
+int trace_probe_append(struct trace_probe *tp, struct trace_probe *to);
+void trace_probe_unlink(struct trace_probe *tp);
+int trace_probe_register_event_call(struct trace_probe *tp);
+int trace_probe_add_file(struct trace_probe *tp, struct trace_event_file *file);
+int trace_probe_remove_file(struct trace_probe *tp,
+ struct trace_event_file *file);
+struct event_file_link *trace_probe_get_file_link(struct trace_probe *tp,
+ struct trace_event_file *file);
+int trace_probe_compare_arg_type(struct trace_probe *a, struct trace_probe *b);
+bool trace_probe_match_command_args(struct trace_probe *tp,
+ int argc, const char **argv);
+
+#define trace_probe_for_each_link(pos, tp) \
+ list_for_each_entry(pos, &(tp)->event->files, list)
+#define trace_probe_for_each_link_rcu(pos, tp) \
+ list_for_each_entry_rcu(pos, &(tp)->event->files, list)
+
+#define TPARG_FL_RETURN BIT(0)
+#define TPARG_FL_KERNEL BIT(1)
+#define TPARG_FL_FENTRY BIT(2)
+#define TPARG_FL_MASK GENMASK(2, 0)
+
+extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i,
+ char *arg, unsigned int flags);
+
+extern int traceprobe_update_arg(struct probe_arg *arg);
+extern void traceprobe_free_probe_arg(struct probe_arg *arg);
+
+extern int traceprobe_split_symbol_offset(char *symbol, long *offset);
+int traceprobe_parse_event_name(const char **pevent, const char **pgroup,
+ char *buf, int offset);
+
+extern int traceprobe_set_print_fmt(struct trace_probe *tp, bool is_return);
+
+#ifdef CONFIG_PERF_EVENTS
+extern struct trace_event_call *
+create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
+ bool is_return);
+extern void destroy_local_trace_kprobe(struct trace_event_call *event_call);
+
+extern struct trace_event_call *
+create_local_trace_uprobe(char *name, unsigned long offs,
+ unsigned long ref_ctr_offset, bool is_return);
+extern void destroy_local_trace_uprobe(struct trace_event_call *event_call);
+#endif
+extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
+ size_t offset, struct trace_probe *tp);
+
+#undef ERRORS
+#define ERRORS \
+ C(FILE_NOT_FOUND, "Failed to find the given file"), \
+ C(NO_REGULAR_FILE, "Not a regular file"), \
+ C(BAD_REFCNT, "Invalid reference counter offset"), \
+ C(REFCNT_OPEN_BRACE, "Reference counter brace is not closed"), \
+ C(BAD_REFCNT_SUFFIX, "Reference counter has wrong suffix"), \
+ C(BAD_UPROBE_OFFS, "Invalid uprobe offset"), \
+ C(MAXACT_NO_KPROBE, "Maxactive is not for kprobe"), \
+ C(BAD_MAXACT, "Invalid maxactive number"), \
+ C(MAXACT_TOO_BIG, "Maxactive is too big"), \
+ C(BAD_PROBE_ADDR, "Invalid probed address or symbol"), \
+ C(BAD_RETPROBE, "Retprobe address must be an function entry"), \
+ C(BAD_ADDR_SUFFIX, "Invalid probed address suffix"), \
+ C(NO_GROUP_NAME, "Group name is not specified"), \
+ C(GROUP_TOO_LONG, "Group name is too long"), \
+ C(BAD_GROUP_NAME, "Group name must follow the same rules as C identifiers"), \
+ C(NO_EVENT_NAME, "Event name is not specified"), \
+ C(EVENT_TOO_LONG, "Event name is too long"), \
+ C(BAD_EVENT_NAME, "Event name must follow the same rules as C identifiers"), \
+ C(EVENT_EXIST, "Given group/event name is already used by another event"), \
+ C(RETVAL_ON_PROBE, "$retval is not available on probe"), \
+ C(BAD_STACK_NUM, "Invalid stack number"), \
+ C(BAD_ARG_NUM, "Invalid argument number"), \
+ C(BAD_VAR, "Invalid $-valiable specified"), \
+ C(BAD_REG_NAME, "Invalid register name"), \
+ C(BAD_MEM_ADDR, "Invalid memory address"), \
+ C(BAD_IMM, "Invalid immediate value"), \
+ C(IMMSTR_NO_CLOSE, "String is not closed with '\"'"), \
+ C(FILE_ON_KPROBE, "File offset is not available with kprobe"), \
+ C(BAD_FILE_OFFS, "Invalid file offset value"), \
+ C(SYM_ON_UPROBE, "Symbol is not available with uprobe"), \
+ C(TOO_MANY_OPS, "Dereference is too much nested"), \
+ C(DEREF_NEED_BRACE, "Dereference needs a brace"), \
+ C(BAD_DEREF_OFFS, "Invalid dereference offset"), \
+ C(DEREF_OPEN_BRACE, "Dereference brace is not closed"), \
+ C(COMM_CANT_DEREF, "$comm can not be dereferenced"), \
+ C(BAD_FETCH_ARG, "Invalid fetch argument"), \
+ C(ARRAY_NO_CLOSE, "Array is not closed"), \
+ C(BAD_ARRAY_SUFFIX, "Array has wrong suffix"), \
+ C(BAD_ARRAY_NUM, "Invalid array size"), \
+ C(ARRAY_TOO_BIG, "Array number is too big"), \
+ C(BAD_TYPE, "Unknown type is specified"), \
+ C(BAD_STRING, "String accepts only memory argument"), \
+ C(BAD_BITFIELD, "Invalid bitfield"), \
+ C(ARG_NAME_TOO_LONG, "Argument name is too long"), \
+ C(NO_ARG_NAME, "Argument name is not specified"), \
+ C(BAD_ARG_NAME, "Argument name must follow the same rules as C identifiers"), \
+ C(USED_ARG_NAME, "This argument name is already used"), \
+ C(ARG_TOO_LONG, "Argument expression is too long"), \
+ C(NO_ARG_BODY, "No argument expression"), \
+ C(BAD_INSN_BNDRY, "Probe point is not an instruction boundary"),\
+ C(FAIL_REG_PROBE, "Failed to register probe event"),\
+ C(DIFF_PROBE_TYPE, "Probe type is different from existing probe"),\
+ C(DIFF_ARG_TYPE, "Argument type or name is different from existing probe"),\
+ C(SAME_PROBE, "There is already the exact same probe event"),
+
+#undef C
+#define C(a, b) TP_ERR_##a
+
+/* Define TP_ERR_ */
+enum { ERRORS };
+
+/* Error text is defined in trace_probe.c */
+
+struct trace_probe_log {
+ const char *subsystem;
+ const char **argv;
+ int argc;
+ int index;
+};
+
+void trace_probe_log_init(const char *subsystem, int argc, const char **argv);
+void trace_probe_log_set_index(int index);
+void trace_probe_log_clear(void);
+void __trace_probe_log_err(int offset, int err);
+
+#define trace_probe_log_err(offs, err) \
+ __trace_probe_log_err(offs, TP_ERR_##err)