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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /kernel/trace/trace_probe.h
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'kernel/trace/trace_probe.h')
-rw-r--r--kernel/trace/trace_probe.h417
1 files changed, 417 insertions, 0 deletions
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
new file mode 100644
index 000000000..5f52668e1
--- /dev/null
+++ b/kernel/trace/trace_probe.h
@@ -0,0 +1,417 @@
+// 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/ctype.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 <asm/bitsperlong.h>
+
+#include "trace.h"
+#include "trace_output.h"
+
+#define MAX_TRACE_ARGS 128
+#define MAX_ARGSTR_LEN 63
+#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
+#define TP_FLAG_REGISTERED 4
+
+
+/* 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)
+
+/*
+ * 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))
+
+static nokprobe_inline void *get_rloc_data(u32 *dl)
+{
+ return (u8 *)dl + get_rloc_offs(*dl);
+}
+
+/* For data_loc conversion */
+static nokprobe_inline void *get_loc_data(u32 *dl, void *ent)
+{
+ return (u8 *)ent + get_rloc_offs(*dl);
+}
+
+/* Data fetch function type */
+typedef void (*fetch_func_t)(struct pt_regs *, void *, void *);
+/* Printing function type */
+typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *, void *);
+
+/* Fetch types */
+enum {
+ FETCH_MTD_reg = 0,
+ FETCH_MTD_stack,
+ FETCH_MTD_retval,
+ FETCH_MTD_comm,
+ FETCH_MTD_memory,
+ FETCH_MTD_symbol,
+ FETCH_MTD_deref,
+ FETCH_MTD_bitfield,
+ FETCH_MTD_file_offset,
+ FETCH_MTD_END,
+};
+
+/* 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 */
+ /* Fetch functions */
+ fetch_func_t fetch[FETCH_MTD_END];
+};
+
+struct fetch_param {
+ fetch_func_t fn;
+ void *data;
+};
+
+/* 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, const char *name, \
+ 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);
+
+#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type
+
+/* Declare macro for basic types */
+#define DECLARE_FETCH_FUNC(method, type) \
+extern void FETCH_FUNC_NAME(method, type)(struct pt_regs *regs, \
+ void *data, void *dest)
+
+#define DECLARE_BASIC_FETCH_FUNCS(method) \
+DECLARE_FETCH_FUNC(method, u8); \
+DECLARE_FETCH_FUNC(method, u16); \
+DECLARE_FETCH_FUNC(method, u32); \
+DECLARE_FETCH_FUNC(method, u64)
+
+DECLARE_BASIC_FETCH_FUNCS(reg);
+#define fetch_reg_string NULL
+#define fetch_reg_string_size NULL
+
+DECLARE_BASIC_FETCH_FUNCS(retval);
+#define fetch_retval_string NULL
+#define fetch_retval_string_size NULL
+
+DECLARE_BASIC_FETCH_FUNCS(symbol);
+DECLARE_FETCH_FUNC(symbol, string);
+DECLARE_FETCH_FUNC(symbol, string_size);
+
+DECLARE_BASIC_FETCH_FUNCS(deref);
+DECLARE_FETCH_FUNC(deref, string);
+DECLARE_FETCH_FUNC(deref, string_size);
+
+DECLARE_BASIC_FETCH_FUNCS(bitfield);
+#define fetch_bitfield_string NULL
+#define fetch_bitfield_string_size NULL
+
+/* comm only makes sense as a string */
+#define fetch_comm_u8 NULL
+#define fetch_comm_u16 NULL
+#define fetch_comm_u32 NULL
+#define fetch_comm_u64 NULL
+DECLARE_FETCH_FUNC(comm, string);
+DECLARE_FETCH_FUNC(comm, string_size);
+
+/*
+ * 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)
+
+/* 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 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(comm, ftype), \
+ASSIGN_FETCH_FUNC(memory, ftype), \
+ASSIGN_FETCH_FUNC(symbol, ftype), \
+ASSIGN_FETCH_FUNC(deref, ftype), \
+ASSIGN_FETCH_FUNC(bitfield, ftype), \
+ASSIGN_FETCH_FUNC(file_offset, ftype), \
+ } \
+ }
+
+#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 FETCH_TYPE_STRING 0
+#define FETCH_TYPE_STRSIZE 1
+
+#ifdef CONFIG_KPROBE_EVENTS
+struct symbol_cache;
+unsigned long update_symbol_cache(struct symbol_cache *sc);
+void free_symbol_cache(struct symbol_cache *sc);
+struct symbol_cache *alloc_symbol_cache(const char *sym, long offset);
+bool trace_kprobe_on_func_entry(struct trace_event_call *call);
+bool trace_kprobe_error_injectable(struct trace_event_call *call);
+#else
+/* uprobes do not support symbol fetch methods */
+#define fetch_symbol_u8 NULL
+#define fetch_symbol_u16 NULL
+#define fetch_symbol_u32 NULL
+#define fetch_symbol_u64 NULL
+#define fetch_symbol_string NULL
+#define fetch_symbol_string_size NULL
+
+struct symbol_cache {
+};
+static inline unsigned long __used update_symbol_cache(struct symbol_cache *sc)
+{
+ return 0;
+}
+
+static inline void __used free_symbol_cache(struct symbol_cache *sc)
+{
+}
+
+static inline struct symbol_cache * __used
+alloc_symbol_cache(const char *sym, long offset)
+{
+ return NULL;
+}
+
+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_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 */
+};
+
+struct trace_probe {
+ unsigned int flags; /* For TP_FLAG_* */
+ struct trace_event_class class;
+ struct trace_event_call call;
+ struct list_head files;
+ 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_is_enabled(struct trace_probe *tp)
+{
+ return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE));
+}
+
+static inline bool trace_probe_is_registered(struct trace_probe *tp)
+{
+ return !!(tp->flags & TP_FLAG_REGISTERED);
+}
+
+static nokprobe_inline void call_fetch(struct fetch_param *fprm,
+ struct pt_regs *regs, void *dest)
+{
+ return fprm->fn(regs, fprm->data, dest);
+}
+
+/* Check the name is good for event/group/fields */
+static inline bool is_good_name(const char *name)
+{
+ if (!isalpha(*name) && *name != '_')
+ return false;
+ while (*++name != '\0') {
+ if (!isalpha(*name) && !isdigit(*name) && *name != '_')
+ return false;
+ }
+ return true;
+}
+
+static inline struct event_file_link *
+find_event_file_link(struct trace_probe *tp, struct trace_event_file *file)
+{
+ struct event_file_link *link;
+
+ list_for_each_entry(link, &tp->files, list)
+ if (link->file == file)
+ return link;
+
+ return NULL;
+}
+
+extern int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
+ struct probe_arg *parg, bool is_return, bool is_kprobe,
+ const struct fetch_type *ftbl);
+
+extern int traceprobe_conflict_field_name(const char *name,
+ struct probe_arg *args, int narg);
+
+extern void 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);
+
+/* Sum up total data length for dynamic arraies (strings) */
+static nokprobe_inline 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 nokprobe_inline 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);
+ }
+}
+
+extern int 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, bool is_return);
+extern void destroy_local_trace_uprobe(struct trace_event_call *event_call);
+#endif