1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * S/390 debug facility
4 *
5 * Copyright IBM Corp. 1999, 2000
6 */
7 #ifndef DEBUG_H
8 #define DEBUG_H
9
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>
15 #include <uapi/asm/debug.h>
16
17 #define DEBUG_MAX_LEVEL 6 /* debug levels range from 0 to 6 */
18 #define DEBUG_OFF_LEVEL -1 /* level where debug is switched off */
19 #define DEBUG_FLUSH_ALL -1 /* parameter to flush all areas */
20 #define DEBUG_MAX_VIEWS 10 /* max number of views in proc fs */
21 #define DEBUG_MAX_NAME_LEN 64 /* max length for a debugfs file name */
22 #define DEBUG_DEFAULT_LEVEL 3 /* initial debug level */
23
24 #define DEBUG_DIR_ROOT "s390dbf" /* name of debug root directory in proc fs */
25
26 #define DEBUG_DATA(entry) (char *)(entry + 1) /* data is stored behind */
27 /* the entry information */
28
29 typedef struct __debug_entry debug_entry_t;
30
31 struct debug_view;
32
33 typedef struct debug_info {
34 struct debug_info *next;
35 struct debug_info *prev;
36 refcount_t ref_count;
37 spinlock_t lock;
38 int level;
39 int nr_areas;
40 int pages_per_area;
41 int buf_size;
42 int entry_size;
43 debug_entry_t ***areas;
44 int active_area;
45 int *active_pages;
46 int *active_entries;
47 struct dentry *debugfs_root_entry;
48 struct dentry *debugfs_entries[DEBUG_MAX_VIEWS];
49 struct debug_view *views[DEBUG_MAX_VIEWS];
50 char name[DEBUG_MAX_NAME_LEN];
51 umode_t mode;
52 } debug_info_t;
53
54 typedef int (debug_header_proc_t) (debug_info_t *id,
55 struct debug_view *view,
56 int area,
57 debug_entry_t *entry,
58 char *out_buf);
59
60 typedef int (debug_format_proc_t) (debug_info_t *id,
61 struct debug_view *view, char *out_buf,
62 const char *in_buf);
63 typedef int (debug_prolog_proc_t) (debug_info_t *id,
64 struct debug_view *view,
65 char *out_buf);
66 typedef int (debug_input_proc_t) (debug_info_t *id,
67 struct debug_view *view,
68 struct file *file,
69 const char __user *user_buf,
70 size_t in_buf_size, loff_t *offset);
71
72 int debug_dflt_header_fn(debug_info_t *id, struct debug_view *view,
73 int area, debug_entry_t *entry, char *out_buf);
74
75 struct debug_view {
76 char name[DEBUG_MAX_NAME_LEN];
77 debug_prolog_proc_t *prolog_proc;
78 debug_header_proc_t *header_proc;
79 debug_format_proc_t *format_proc;
80 debug_input_proc_t *input_proc;
81 void *private_data;
82 };
83
84 extern struct debug_view debug_hex_ascii_view;
85 extern struct debug_view debug_raw_view;
86 extern struct debug_view debug_sprintf_view;
87
88 /* do NOT use the _common functions */
89
90 debug_entry_t *debug_event_common(debug_info_t *id, int level,
91 const void *data, int length);
92
93 debug_entry_t *debug_exception_common(debug_info_t *id, int level,
94 const void *data, int length);
95
96 /* Debug Feature API: */
97
98 debug_info_t *debug_register(const char *name, int pages, int nr_areas,
99 int buf_size);
100
101 debug_info_t *debug_register_mode(const char *name, int pages, int nr_areas,
102 int buf_size, umode_t mode, uid_t uid,
103 gid_t gid);
104
105 void debug_unregister(debug_info_t *id);
106
107 void debug_set_level(debug_info_t *id, int new_level);
108
109 void debug_set_critical(void);
110
111 void debug_stop_all(void);
112
113 /**
114 * debug_level_enabled() - Returns true if debug events for the specified
115 * level would be logged. Otherwise returns false.
116 *
117 * @id: handle for debug log
118 * @level: debug level
119 *
120 * Return:
121 * - %true if level is less or equal to the current debug level.
122 */
123 static inline bool debug_level_enabled(debug_info_t *id, int level)
124 {
125 return level <= id->level;
126 }
127
128 /**
129 * debug_event() - writes binary debug entry to active debug area
130 * (if level <= actual debug level)
131 *
132 * @id: handle for debug log
133 * @level: debug level
134 * @data: pointer to data for debug entry
135 * @length: length of data in bytes
136 *
137 * Return:
138 * - Address of written debug entry
139 * - %NULL if error
140 */
141 static inline debug_entry_t *debug_event(debug_info_t *id, int level,
142 void *data, int length)
143 {
144 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
145 return NULL;
146 return debug_event_common(id, level, data, length);
147 }
148
149 /**
150 * debug_int_event() - writes unsigned integer debug entry to active debug area
151 * (if level <= actual debug level)
152 *
153 * @id: handle for debug log
154 * @level: debug level
155 * @tag: integer value for debug entry
156 *
157 * Return:
158 * - Address of written debug entry
159 * - %NULL if error
160 */
161 static inline debug_entry_t *debug_int_event(debug_info_t *id, int level,
162 unsigned int tag)
163 {
164 unsigned int t = tag;
165
166 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
167 return NULL;
168 return debug_event_common(id, level, &t, sizeof(unsigned int));
169 }
170
171 /**
172 * debug_long_event() - writes unsigned long debug entry to active debug area
173 * (if level <= actual debug level)
174 *
175 * @id: handle for debug log
176 * @level: debug level
177 * @tag: long integer value for debug entry
178 *
179 * Return:
180 * - Address of written debug entry
181 * - %NULL if error
182 */
183 static inline debug_entry_t *debug_long_event(debug_info_t *id, int level,
184 unsigned long tag)
185 {
186 unsigned long t = tag;
187
188 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
189 return NULL;
190 return debug_event_common(id, level, &t, sizeof(unsigned long));
191 }
192
193 /**
194 * debug_text_event() - writes string debug entry in ascii format to active
195 * debug area (if level <= actual debug level)
196 *
197 * @id: handle for debug log
198 * @level: debug level
199 * @txt: string for debug entry
200 *
201 * Return:
202 * - Address of written debug entry
203 * - %NULL if error
204 */
205 static inline debug_entry_t *debug_text_event(debug_info_t *id, int level,
206 const char *txt)
207 {
208 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
209 return NULL;
210 return debug_event_common(id, level, txt, strlen(txt));
211 }
212
213 /*
214 * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
215 * stored in the s390dbf. See Documentation/s390/s390dbf.rst for more details!
216 */
217 extern debug_entry_t *
218 __debug_sprintf_event(debug_info_t *id, int level, char *string, ...)
219 __attribute__ ((format(printf, 3, 4)));
220
221 /**
222 * debug_sprintf_event() - writes debug entry with format string
223 * and varargs (longs) to active debug area
224 * (if level $<=$ actual debug level).
225 *
226 * @_id: handle for debug log
227 * @_level: debug level
228 * @_fmt: format string for debug entry
229 * @...: varargs used as in sprintf()
230 *
231 * Return:
232 * - Address of written debug entry
233 * - %NULL if error
234 *
235 * floats and long long datatypes cannot be used as varargs.
236 */
237 #define debug_sprintf_event(_id, _level, _fmt, ...) \
238 ({ \
239 debug_entry_t *__ret; \
240 debug_info_t *__id = _id; \
241 int __level = _level; \
242 \
243 if ((!__id) || (__level > __id->level)) \
244 __ret = NULL; \
245 else \
246 __ret = __debug_sprintf_event(__id, __level, \
247 _fmt, ## __VA_ARGS__); \
248 __ret; \
249 })
250
251 /**
252 * debug_exception() - writes binary debug entry to active debug area
253 * (if level <= actual debug level)
254 * and switches to next debug area
255 *
256 * @id: handle for debug log
257 * @level: debug level
258 * @data: pointer to data for debug entry
259 * @length: length of data in bytes
260 *
261 * Return:
262 * - Address of written debug entry
263 * - %NULL if error
264 */
265 static inline debug_entry_t *debug_exception(debug_info_t *id, int level,
266 void *data, int length)
267 {
268 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
269 return NULL;
270 return debug_exception_common(id, level, data, length);
271 }
272
273 /**
274 * debug_int_exception() - writes unsigned int debug entry to active debug area
275 * (if level <= actual debug level)
276 * and switches to next debug area
277 *
278 * @id: handle for debug log
279 * @level: debug level
280 * @tag: integer value for debug entry
281 *
282 * Return:
283 * - Address of written debug entry
284 * - %NULL if error
285 */
286 static inline debug_entry_t *debug_int_exception(debug_info_t *id, int level,
287 unsigned int tag)
288 {
289 unsigned int t = tag;
290
291 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
292 return NULL;
293 return debug_exception_common(id, level, &t, sizeof(unsigned int));
294 }
295
296 /**
297 * debug_long_exception() - writes long debug entry to active debug area
298 * (if level <= actual debug level)
299 * and switches to next debug area
300 *
301 * @id: handle for debug log
302 * @level: debug level
303 * @tag: long integer value for debug entry
304 *
305 * Return:
306 * - Address of written debug entry
307 * - %NULL if error
308 */
309 static inline debug_entry_t *debug_long_exception (debug_info_t *id, int level,
310 unsigned long tag)
311 {
312 unsigned long t = tag;
313
314 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
315 return NULL;
316 return debug_exception_common(id, level, &t, sizeof(unsigned long));
317 }
318
319 /**
320 * debug_text_exception() - writes string debug entry in ascii format to active
321 * debug area (if level <= actual debug level)
322 * and switches to next debug area
323 * area
324 *
325 * @id: handle for debug log
326 * @level: debug level
327 * @txt: string for debug entry
328 *
329 * Return:
330 * - Address of written debug entry
331 * - %NULL if error
332 */
333 static inline debug_entry_t *debug_text_exception(debug_info_t *id, int level,
334 const char *txt)
335 {
336 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
337 return NULL;
338 return debug_exception_common(id, level, txt, strlen(txt));
339 }
340
341 /*
342 * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
343 * stored in the s390dbf. See Documentation/s390/s390dbf.rst for more details!
344 */
345 extern debug_entry_t *
346 __debug_sprintf_exception(debug_info_t *id, int level, char *string, ...)
347 __attribute__ ((format(printf, 3, 4)));
348
349
350 /**
351 * debug_sprintf_exception() - writes debug entry with format string and
352 * varargs (longs) to active debug area
353 * (if level <= actual debug level)
354 * and switches to next debug area.
355 *
356 * @_id: handle for debug log
357 * @_level: debug level
358 * @_fmt: format string for debug entry
359 * @...: varargs used as in sprintf()
360 *
361 * Return:
362 * - Address of written debug entry
363 * - %NULL if error
364 *
365 * floats and long long datatypes cannot be used as varargs.
366 */
367 #define debug_sprintf_exception(_id, _level, _fmt, ...) \
368 ({ \
369 debug_entry_t *__ret; \
370 debug_info_t *__id = _id; \
371 int __level = _level; \
372 \
373 if ((!__id) || (__level > __id->level)) \
374 __ret = NULL; \
375 else \
376 __ret = __debug_sprintf_exception(__id, __level, \
377 _fmt, ## __VA_ARGS__);\
378 __ret; \
379 })
380
381 int debug_register_view(debug_info_t *id, struct debug_view *view);
382
383 int debug_unregister_view(debug_info_t *id, struct debug_view *view);
384
385 /*
386 define the debug levels:
387 - 0 No debugging output to console or syslog
388 - 1 Log internal errors to syslog, ignore check conditions
389 - 2 Log internal errors and check conditions to syslog
390 - 3 Log internal errors to console, log check conditions to syslog
391 - 4 Log internal errors and check conditions to console
392 - 5 panic on internal errors, log check conditions to console
393 - 6 panic on both, internal errors and check conditions
394 */
395
396 #ifndef DEBUG_LEVEL
397 #define DEBUG_LEVEL 4
398 #endif
399
400 #define INTERNAL_ERRMSG(x,y...) "E" __FILE__ "%d: " x, __LINE__, y
401 #define INTERNAL_WRNMSG(x,y...) "W" __FILE__ "%d: " x, __LINE__, y
402 #define INTERNAL_INFMSG(x,y...) "I" __FILE__ "%d: " x, __LINE__, y
403 #define INTERNAL_DEBMSG(x,y...) "D" __FILE__ "%d: " x, __LINE__, y
404
405 #if DEBUG_LEVEL > 0
406 #define PRINT_DEBUG(x...) printk(KERN_DEBUG PRINTK_HEADER x)
407 #define PRINT_INFO(x...) printk(KERN_INFO PRINTK_HEADER x)
408 #define PRINT_WARN(x...) printk(KERN_WARNING PRINTK_HEADER x)
409 #define PRINT_ERR(x...) printk(KERN_ERR PRINTK_HEADER x)
410 #define PRINT_FATAL(x...) panic(PRINTK_HEADER x)
411 #else
412 #define PRINT_DEBUG(x...) printk(KERN_DEBUG PRINTK_HEADER x)
413 #define PRINT_INFO(x...) printk(KERN_DEBUG PRINTK_HEADER x)
414 #define PRINT_WARN(x...) printk(KERN_DEBUG PRINTK_HEADER x)
415 #define PRINT_ERR(x...) printk(KERN_DEBUG PRINTK_HEADER x)
416 #define PRINT_FATAL(x...) printk(KERN_DEBUG PRINTK_HEADER x)
417 #endif /* DASD_DEBUG */
418
419 #endif /* DEBUG_H */