1 /* SPDX-License-Identifier: GPL-2.0 */
5 * Copyright IBM Corp. 1999, 2020
7 #ifndef _ASM_S390_DEBUG_H
8 #define _ASM_S390_DEBUG_H
10 #include <linux/string.h>
11 #include <linux/spinlock.h>
12 #include <linux/kernel.h>
13 #include <linux/time.h>
14 #include <linux/refcount.h>
16 #include <linux/init.h>
18 #define DEBUG_MAX_LEVEL 6 /* debug levels range from 0 to 6 */
19 #define DEBUG_OFF_LEVEL -1 /* level where debug is switched off */
20 #define DEBUG_FLUSH_ALL -1 /* parameter to flush all areas */
21 #define DEBUG_MAX_VIEWS 10 /* max number of views in proc fs */
22 #define DEBUG_MAX_NAME_LEN 64 /* max length for a debugfs file name */
23 #define DEBUG_DEFAULT_LEVEL 3 /* initial debug level */
25 #define DEBUG_DIR_ROOT "s390dbf" /* name of debug root directory in proc fs */
27 #define DEBUG_DATA(entry) (char *)(entry + 1) /* data is stored behind */
28 /* the entry information */
30 #define __DEBUG_FEATURE_VERSION 3 /* version of debug feature */
32 struct __debug_entry {
33 unsigned long clock : 60;
34 unsigned long exception : 1;
35 unsigned long level : 3;
40 typedef struct __debug_entry debug_entry_t;
44 typedef struct debug_info {
45 struct debug_info *next;
46 struct debug_info *prev;
54 debug_entry_t ***areas;
58 struct dentry *debugfs_root_entry;
59 struct dentry *debugfs_entries[DEBUG_MAX_VIEWS];
60 struct debug_view *views[DEBUG_MAX_VIEWS];
61 char name[DEBUG_MAX_NAME_LEN];
65 typedef int (debug_header_proc_t) (debug_info_t *id,
66 struct debug_view *view,
69 char *out_buf, size_t out_buf_size);
71 typedef int (debug_format_proc_t) (debug_info_t *id,
72 struct debug_view *view, char *out_buf,
75 typedef int (debug_prolog_proc_t) (debug_info_t *id,
76 struct debug_view *view,
77 char *out_buf, size_t out_buf_size);
78 typedef int (debug_input_proc_t) (debug_info_t *id,
79 struct debug_view *view,
81 const char __user *user_buf,
82 size_t in_buf_size, loff_t *offset);
84 int debug_dflt_header_fn(debug_info_t *id, struct debug_view *view,
85 int area, debug_entry_t *entry,
86 char *out_buf, size_t out_buf_size);
89 char name[DEBUG_MAX_NAME_LEN];
90 debug_prolog_proc_t *prolog_proc;
91 debug_header_proc_t *header_proc;
92 debug_format_proc_t *format_proc;
93 debug_input_proc_t *input_proc;
97 extern struct debug_view debug_hex_ascii_view;
98 extern struct debug_view debug_sprintf_view;
100 /* do NOT use the _common functions */
102 debug_entry_t *debug_event_common(debug_info_t *id, int level,
103 const void *data, int length);
105 debug_entry_t *debug_exception_common(debug_info_t *id, int level,
106 const void *data, int length);
108 /* Debug Feature API: */
110 debug_info_t *debug_register(const char *name, int pages, int nr_areas,
113 debug_info_t *debug_register_mode(const char *name, int pages, int nr_areas,
114 int buf_size, umode_t mode, uid_t uid,
117 void debug_unregister(debug_info_t *id);
119 void debug_set_level(debug_info_t *id, int new_level);
121 void debug_set_critical(void);
123 void debug_stop_all(void);
126 * debug_level_enabled() - Returns true if debug events for the specified
127 * level would be logged. Otherwise returns false.
129 * @id: handle for debug log
130 * @level: debug level
133 * - %true if level is less or equal to the current debug level.
135 static inline bool debug_level_enabled(debug_info_t *id, int level)
137 return level <= id->level;
141 * debug_event() - writes binary debug entry to active debug area
142 * (if level <= actual debug level)
144 * @id: handle for debug log
145 * @level: debug level
146 * @data: pointer to data for debug entry
147 * @length: length of data in bytes
150 * - Address of written debug entry
153 static inline debug_entry_t *debug_event(debug_info_t *id, int level,
154 void *data, int length)
156 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
158 return debug_event_common(id, level, data, length);
162 * debug_int_event() - writes unsigned integer debug entry to active debug area
163 * (if level <= actual debug level)
165 * @id: handle for debug log
166 * @level: debug level
167 * @tag: integer value for debug entry
170 * - Address of written debug entry
173 static inline debug_entry_t *debug_int_event(debug_info_t *id, int level,
176 unsigned int t = tag;
178 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
180 return debug_event_common(id, level, &t, sizeof(unsigned int));
184 * debug_long_event() - writes unsigned long debug entry to active debug area
185 * (if level <= actual debug level)
187 * @id: handle for debug log
188 * @level: debug level
189 * @tag: long integer value for debug entry
192 * - Address of written debug entry
195 static inline debug_entry_t *debug_long_event(debug_info_t *id, int level,
198 unsigned long t = tag;
200 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
202 return debug_event_common(id, level, &t, sizeof(unsigned long));
206 * debug_text_event() - writes string debug entry in ascii format to active
207 * debug area (if level <= actual debug level)
209 * @id: handle for debug log
210 * @level: debug level
211 * @txt: string for debug entry
214 * - Address of written debug entry
217 static inline debug_entry_t *debug_text_event(debug_info_t *id, int level,
220 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
222 return debug_event_common(id, level, txt, strlen(txt));
226 * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
227 * stored in the s390dbf. See Documentation/arch/s390/s390dbf.rst for more details!
229 extern debug_entry_t *
230 __debug_sprintf_event(debug_info_t *id, int level, char *string, ...)
231 __attribute__ ((format(printf, 3, 4)));
234 * debug_sprintf_event() - writes debug entry with format string
235 * and varargs (longs) to active debug area
236 * (if level $<=$ actual debug level).
238 * @_id: handle for debug log
239 * @_level: debug level
240 * @_fmt: format string for debug entry
241 * @...: varargs used as in sprintf()
244 * - Address of written debug entry
247 * floats and long long datatypes cannot be used as varargs.
249 #define debug_sprintf_event(_id, _level, _fmt, ...) \
251 debug_entry_t *__ret; \
252 debug_info_t *__id = _id; \
253 int __level = _level; \
255 if ((!__id) || (__level > __id->level)) \
258 __ret = __debug_sprintf_event(__id, __level, \
259 _fmt, ## __VA_ARGS__); \
264 * debug_exception() - writes binary debug entry to active debug area
265 * (if level <= actual debug level)
266 * and switches to next debug area
268 * @id: handle for debug log
269 * @level: debug level
270 * @data: pointer to data for debug entry
271 * @length: length of data in bytes
274 * - Address of written debug entry
277 static inline debug_entry_t *debug_exception(debug_info_t *id, int level,
278 void *data, int length)
280 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
282 return debug_exception_common(id, level, data, length);
286 * debug_int_exception() - writes unsigned int debug entry to active debug area
287 * (if level <= actual debug level)
288 * and switches to next debug area
290 * @id: handle for debug log
291 * @level: debug level
292 * @tag: integer value for debug entry
295 * - Address of written debug entry
298 static inline debug_entry_t *debug_int_exception(debug_info_t *id, int level,
301 unsigned int t = tag;
303 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
305 return debug_exception_common(id, level, &t, sizeof(unsigned int));
309 * debug_long_exception() - writes long debug entry to active debug area
310 * (if level <= actual debug level)
311 * and switches to next debug area
313 * @id: handle for debug log
314 * @level: debug level
315 * @tag: long integer value for debug entry
318 * - Address of written debug entry
321 static inline debug_entry_t *debug_long_exception (debug_info_t *id, int level,
324 unsigned long t = tag;
326 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
328 return debug_exception_common(id, level, &t, sizeof(unsigned long));
332 * debug_text_exception() - writes string debug entry in ascii format to active
333 * debug area (if level <= actual debug level)
334 * and switches to next debug area
337 * @id: handle for debug log
338 * @level: debug level
339 * @txt: string for debug entry
342 * - Address of written debug entry
345 static inline debug_entry_t *debug_text_exception(debug_info_t *id, int level,
348 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
350 return debug_exception_common(id, level, txt, strlen(txt));
354 * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
355 * stored in the s390dbf. See Documentation/arch/s390/s390dbf.rst for more details!
357 extern debug_entry_t *
358 __debug_sprintf_exception(debug_info_t *id, int level, char *string, ...)
359 __attribute__ ((format(printf, 3, 4)));
363 * debug_sprintf_exception() - writes debug entry with format string and
364 * varargs (longs) to active debug area
365 * (if level <= actual debug level)
366 * and switches to next debug area.
368 * @_id: handle for debug log
369 * @_level: debug level
370 * @_fmt: format string for debug entry
371 * @...: varargs used as in sprintf()
374 * - Address of written debug entry
377 * floats and long long datatypes cannot be used as varargs.
379 #define debug_sprintf_exception(_id, _level, _fmt, ...) \
381 debug_entry_t *__ret; \
382 debug_info_t *__id = _id; \
383 int __level = _level; \
385 if ((!__id) || (__level > __id->level)) \
388 __ret = __debug_sprintf_exception(__id, __level, \
389 _fmt, ## __VA_ARGS__);\
393 int debug_register_view(debug_info_t *id, struct debug_view *view);
395 int debug_unregister_view(debug_info_t *id, struct debug_view *view);
400 * Note: Initial page and area numbers must be fixed to allow static
401 * initialization. This enables very early tracing. Changes to these values
402 * must be reflected in __DEFINE_STATIC_AREA.
404 #define EARLY_PAGES 8
405 #define EARLY_AREAS 1
407 #define VNAME(var, suffix) __##var##_##suffix
410 * Define static areas for early trace data. During boot debug_register_static()
411 * will replace these with dynamically allocated areas to allow custom page and
412 * area sizes, and dynamic resizing.
414 #define __DEFINE_STATIC_AREA(var) \
415 static char VNAME(var, data)[EARLY_PAGES][PAGE_SIZE] __initdata; \
416 static debug_entry_t *VNAME(var, pages)[EARLY_PAGES] __initdata = { \
417 (debug_entry_t *)VNAME(var, data)[0], \
418 (debug_entry_t *)VNAME(var, data)[1], \
419 (debug_entry_t *)VNAME(var, data)[2], \
420 (debug_entry_t *)VNAME(var, data)[3], \
421 (debug_entry_t *)VNAME(var, data)[4], \
422 (debug_entry_t *)VNAME(var, data)[5], \
423 (debug_entry_t *)VNAME(var, data)[6], \
424 (debug_entry_t *)VNAME(var, data)[7], \
426 static debug_entry_t **VNAME(var, areas)[EARLY_AREAS] __initdata = { \
427 (debug_entry_t **)VNAME(var, pages), \
429 static int VNAME(var, active_pages)[EARLY_AREAS] __initdata; \
430 static int VNAME(var, active_entries)[EARLY_AREAS] __initdata
432 #define __DEBUG_INFO_INIT(var, _name, _buf_size) { \
435 .ref_count = REFCOUNT_INIT(1), \
436 .lock = __SPIN_LOCK_UNLOCKED(var.lock), \
437 .level = DEBUG_DEFAULT_LEVEL, \
438 .nr_areas = EARLY_AREAS, \
439 .pages_per_area = EARLY_PAGES, \
440 .buf_size = (_buf_size), \
441 .entry_size = sizeof(debug_entry_t) + (_buf_size), \
442 .areas = VNAME(var, areas), \
444 .active_pages = VNAME(var, active_pages), \
445 .active_entries = VNAME(var, active_entries), \
446 .debugfs_root_entry = NULL, \
447 .debugfs_entries = { NULL }, \
453 #define __REGISTER_STATIC_DEBUG_INFO(var, name, pages, areas, view) \
454 static int __init VNAME(var, reg)(void) \
456 debug_register_static(&var, (pages), (areas)); \
457 debug_register_view(&var, (view)); \
460 arch_initcall(VNAME(var, reg))
463 * DEFINE_STATIC_DEBUG_INFO - Define static debug_info_t
465 * @var: Name of debug_info_t variable
466 * @name: Name of debug log (e.g. used for debugfs entry)
467 * @pages: Number of pages per area
468 * @nr_areas: Number of debug areas
469 * @buf_size: Size of data area in each debug entry
470 * @view: Pointer to debug view struct
472 * Define a static debug_info_t for early tracing. The associated debugfs log
473 * is automatically registered with the specified debug view.
475 * Important: Users of this macro must not call any of the
476 * debug_register/_unregister() functions for this debug_info_t!
478 * Note: Tracing will start with a fixed number of initial pages and areas.
479 * The debug area will be changed to use the specified numbers during
482 #define DEFINE_STATIC_DEBUG_INFO(var, name, pages, nr_areas, buf_size, view) \
483 __DEFINE_STATIC_AREA(var); \
484 static debug_info_t __refdata var = \
485 __DEBUG_INFO_INIT(var, (name), (buf_size)); \
486 __REGISTER_STATIC_DEBUG_INFO(var, name, pages, nr_areas, view)
488 void debug_register_static(debug_info_t *id, int pages_per_area, int nr_areas);
492 #endif /* _ASM_S390_DEBUG_H */