1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * S/390 debug facility
4 *
5 * Copyright IBM Corp. 1999, 2020
6 */
7 #ifndef _ASM_S390_DEBUG_H
8 #define _ASM_S390_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 <linux/fs.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 #define __DEBUG_FEATURE_VERSION 3 /* version of debug feature */
30
31 struct __debug_entry {
32 unsigned long clock : 60;
33 unsigned long exception : 1;
34 unsigned long level : 3;
35 void *caller;
36 unsigned short cpu;
37 } __packed;
38
39 typedef struct __debug_entry debug_entry_t;
40
41 struct debug_view;
42
43 typedef struct debug_info {
44 struct debug_info *next;
45 struct debug_info *prev;
46 refcount_t ref_count;
47 spinlock_t lock;
48 int level;
49 int nr_areas;
50 int pages_per_area;
51 int buf_size;
52 int entry_size;
53 debug_entry_t ***areas;
54 int active_area;
55 int *active_pages;
56 int *active_entries;
57 struct dentry *debugfs_root_entry;
58 struct dentry *debugfs_entries[DEBUG_MAX_VIEWS];
59 struct debug_view *views[DEBUG_MAX_VIEWS];
60 char name[DEBUG_MAX_NAME_LEN];
61 umode_t mode;
62 } debug_info_t;
63
64 typedef int (debug_header_proc_t) (debug_info_t *id,
65 struct debug_view *view,
66 int area,
67 debug_entry_t *entry,
68 char *out_buf);
69
70 typedef int (debug_format_proc_t) (debug_info_t *id,
71 struct debug_view *view, char *out_buf,
72 const char *in_buf);
73 typedef int (debug_prolog_proc_t) (debug_info_t *id,
74 struct debug_view *view,
75 char *out_buf);
76 typedef int (debug_input_proc_t) (debug_info_t *id,
77 struct debug_view *view,
78 struct file *file,
79 const char __user *user_buf,
80 size_t in_buf_size, loff_t *offset);
81
82 int debug_dflt_header_fn(debug_info_t *id, struct debug_view *view,
83 int area, debug_entry_t *entry, char *out_buf);
84
85 struct debug_view {
86 char name[DEBUG_MAX_NAME_LEN];
87 debug_prolog_proc_t *prolog_proc;
88 debug_header_proc_t *header_proc;
89 debug_format_proc_t *format_proc;
90 debug_input_proc_t *input_proc;
91 void *private_data;
92 };
93
94 extern struct debug_view debug_hex_ascii_view;
95 extern struct debug_view debug_sprintf_view;
96
97 /* do NOT use the _common functions */
98
99 debug_entry_t *debug_event_common(debug_info_t *id, int level,
100 const void *data, int length);
101
102 debug_entry_t *debug_exception_common(debug_info_t *id, int level,
103 const void *data, int length);
104
105 /* Debug Feature API: */
106
107 debug_info_t *debug_register(const char *name, int pages, int nr_areas,
108 int buf_size);
109
110 debug_info_t *debug_register_mode(const char *name, int pages, int nr_areas,
111 int buf_size, umode_t mode, uid_t uid,
112 gid_t gid);
113
114 void debug_unregister(debug_info_t *id);
115
116 void debug_set_level(debug_info_t *id, int new_level);
117
118 void debug_set_critical(void);
119
120 void debug_stop_all(void);
121
122 /**
123 * debug_level_enabled() - Returns true if debug events for the specified
124 * level would be logged. Otherwise returns false.
125 *
126 * @id: handle for debug log
127 * @level: debug level
128 *
129 * Return:
130 * - %true if level is less or equal to the current debug level.
131 */
debug_level_enabled(debug_info_t * id,int level)132 static inline bool debug_level_enabled(debug_info_t *id, int level)
133 {
134 return level <= id->level;
135 }
136
137 /**
138 * debug_event() - writes binary debug entry to active debug area
139 * (if level <= actual debug level)
140 *
141 * @id: handle for debug log
142 * @level: debug level
143 * @data: pointer to data for debug entry
144 * @length: length of data in bytes
145 *
146 * Return:
147 * - Address of written debug entry
148 * - %NULL if error
149 */
debug_event(debug_info_t * id,int level,void * data,int length)150 static inline debug_entry_t *debug_event(debug_info_t *id, int level,
151 void *data, int length)
152 {
153 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
154 return NULL;
155 return debug_event_common(id, level, data, length);
156 }
157
158 /**
159 * debug_int_event() - writes unsigned integer debug entry to active debug area
160 * (if level <= actual debug level)
161 *
162 * @id: handle for debug log
163 * @level: debug level
164 * @tag: integer value for debug entry
165 *
166 * Return:
167 * - Address of written debug entry
168 * - %NULL if error
169 */
debug_int_event(debug_info_t * id,int level,unsigned int tag)170 static inline debug_entry_t *debug_int_event(debug_info_t *id, int level,
171 unsigned int tag)
172 {
173 unsigned int t = tag;
174
175 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
176 return NULL;
177 return debug_event_common(id, level, &t, sizeof(unsigned int));
178 }
179
180 /**
181 * debug_long_event() - writes unsigned long debug entry to active debug area
182 * (if level <= actual debug level)
183 *
184 * @id: handle for debug log
185 * @level: debug level
186 * @tag: long integer value for debug entry
187 *
188 * Return:
189 * - Address of written debug entry
190 * - %NULL if error
191 */
debug_long_event(debug_info_t * id,int level,unsigned long tag)192 static inline debug_entry_t *debug_long_event(debug_info_t *id, int level,
193 unsigned long tag)
194 {
195 unsigned long t = tag;
196
197 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
198 return NULL;
199 return debug_event_common(id, level, &t, sizeof(unsigned long));
200 }
201
202 /**
203 * debug_text_event() - writes string debug entry in ascii format to active
204 * debug area (if level <= actual debug level)
205 *
206 * @id: handle for debug log
207 * @level: debug level
208 * @txt: string for debug entry
209 *
210 * Return:
211 * - Address of written debug entry
212 * - %NULL if error
213 */
debug_text_event(debug_info_t * id,int level,const char * txt)214 static inline debug_entry_t *debug_text_event(debug_info_t *id, int level,
215 const char *txt)
216 {
217 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
218 return NULL;
219 return debug_event_common(id, level, txt, strlen(txt));
220 }
221
222 /*
223 * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
224 * stored in the s390dbf. See Documentation/s390/s390dbf.rst for more details!
225 */
226 extern debug_entry_t *
227 __debug_sprintf_event(debug_info_t *id, int level, char *string, ...)
228 __attribute__ ((format(printf, 3, 4)));
229
230 /**
231 * debug_sprintf_event() - writes debug entry with format string
232 * and varargs (longs) to active debug area
233 * (if level $<=$ actual debug level).
234 *
235 * @_id: handle for debug log
236 * @_level: debug level
237 * @_fmt: format string for debug entry
238 * @...: varargs used as in sprintf()
239 *
240 * Return:
241 * - Address of written debug entry
242 * - %NULL if error
243 *
244 * floats and long long datatypes cannot be used as varargs.
245 */
246 #define debug_sprintf_event(_id, _level, _fmt, ...) \
247 ({ \
248 debug_entry_t *__ret; \
249 debug_info_t *__id = _id; \
250 int __level = _level; \
251 \
252 if ((!__id) || (__level > __id->level)) \
253 __ret = NULL; \
254 else \
255 __ret = __debug_sprintf_event(__id, __level, \
256 _fmt, ## __VA_ARGS__); \
257 __ret; \
258 })
259
260 /**
261 * debug_exception() - writes binary debug entry to active debug area
262 * (if level <= actual debug level)
263 * and switches to next debug area
264 *
265 * @id: handle for debug log
266 * @level: debug level
267 * @data: pointer to data for debug entry
268 * @length: length of data in bytes
269 *
270 * Return:
271 * - Address of written debug entry
272 * - %NULL if error
273 */
debug_exception(debug_info_t * id,int level,void * data,int length)274 static inline debug_entry_t *debug_exception(debug_info_t *id, int level,
275 void *data, int length)
276 {
277 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
278 return NULL;
279 return debug_exception_common(id, level, data, length);
280 }
281
282 /**
283 * debug_int_exception() - writes unsigned int debug entry to active debug area
284 * (if level <= actual debug level)
285 * and switches to next debug area
286 *
287 * @id: handle for debug log
288 * @level: debug level
289 * @tag: integer value for debug entry
290 *
291 * Return:
292 * - Address of written debug entry
293 * - %NULL if error
294 */
debug_int_exception(debug_info_t * id,int level,unsigned int tag)295 static inline debug_entry_t *debug_int_exception(debug_info_t *id, int level,
296 unsigned int tag)
297 {
298 unsigned int t = tag;
299
300 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
301 return NULL;
302 return debug_exception_common(id, level, &t, sizeof(unsigned int));
303 }
304
305 /**
306 * debug_long_exception() - writes long debug entry to active debug area
307 * (if level <= actual debug level)
308 * and switches to next debug area
309 *
310 * @id: handle for debug log
311 * @level: debug level
312 * @tag: long integer value for debug entry
313 *
314 * Return:
315 * - Address of written debug entry
316 * - %NULL if error
317 */
debug_long_exception(debug_info_t * id,int level,unsigned long tag)318 static inline debug_entry_t *debug_long_exception (debug_info_t *id, int level,
319 unsigned long tag)
320 {
321 unsigned long t = tag;
322
323 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
324 return NULL;
325 return debug_exception_common(id, level, &t, sizeof(unsigned long));
326 }
327
328 /**
329 * debug_text_exception() - writes string debug entry in ascii format to active
330 * debug area (if level <= actual debug level)
331 * and switches to next debug area
332 * area
333 *
334 * @id: handle for debug log
335 * @level: debug level
336 * @txt: string for debug entry
337 *
338 * Return:
339 * - Address of written debug entry
340 * - %NULL if error
341 */
debug_text_exception(debug_info_t * id,int level,const char * txt)342 static inline debug_entry_t *debug_text_exception(debug_info_t *id, int level,
343 const char *txt)
344 {
345 if ((!id) || (level > id->level) || (id->pages_per_area == 0))
346 return NULL;
347 return debug_exception_common(id, level, txt, strlen(txt));
348 }
349
350 /*
351 * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
352 * stored in the s390dbf. See Documentation/s390/s390dbf.rst for more details!
353 */
354 extern debug_entry_t *
355 __debug_sprintf_exception(debug_info_t *id, int level, char *string, ...)
356 __attribute__ ((format(printf, 3, 4)));
357
358
359 /**
360 * debug_sprintf_exception() - writes debug entry with format string and
361 * varargs (longs) to active debug area
362 * (if level <= actual debug level)
363 * and switches to next debug area.
364 *
365 * @_id: handle for debug log
366 * @_level: debug level
367 * @_fmt: format string for debug entry
368 * @...: varargs used as in sprintf()
369 *
370 * Return:
371 * - Address of written debug entry
372 * - %NULL if error
373 *
374 * floats and long long datatypes cannot be used as varargs.
375 */
376 #define debug_sprintf_exception(_id, _level, _fmt, ...) \
377 ({ \
378 debug_entry_t *__ret; \
379 debug_info_t *__id = _id; \
380 int __level = _level; \
381 \
382 if ((!__id) || (__level > __id->level)) \
383 __ret = NULL; \
384 else \
385 __ret = __debug_sprintf_exception(__id, __level, \
386 _fmt, ## __VA_ARGS__);\
387 __ret; \
388 })
389
390 int debug_register_view(debug_info_t *id, struct debug_view *view);
391
392 int debug_unregister_view(debug_info_t *id, struct debug_view *view);
393
394 /*
395 define the debug levels:
396 - 0 No debugging output to console or syslog
397 - 1 Log internal errors to syslog, ignore check conditions
398 - 2 Log internal errors and check conditions to syslog
399 - 3 Log internal errors to console, log check conditions to syslog
400 - 4 Log internal errors and check conditions to console
401 - 5 panic on internal errors, log check conditions to console
402 - 6 panic on both, internal errors and check conditions
403 */
404
405 #ifndef DEBUG_LEVEL
406 #define DEBUG_LEVEL 4
407 #endif
408
409 #define INTERNAL_ERRMSG(x,y...) "E" __FILE__ "%d: " x, __LINE__, y
410 #define INTERNAL_WRNMSG(x,y...) "W" __FILE__ "%d: " x, __LINE__, y
411 #define INTERNAL_INFMSG(x,y...) "I" __FILE__ "%d: " x, __LINE__, y
412 #define INTERNAL_DEBMSG(x,y...) "D" __FILE__ "%d: " x, __LINE__, y
413
414 #if DEBUG_LEVEL > 0
415 #define PRINT_DEBUG(x...) printk(KERN_DEBUG PRINTK_HEADER x)
416 #define PRINT_INFO(x...) printk(KERN_INFO PRINTK_HEADER x)
417 #define PRINT_WARN(x...) printk(KERN_WARNING PRINTK_HEADER x)
418 #define PRINT_ERR(x...) printk(KERN_ERR PRINTK_HEADER x)
419 #define PRINT_FATAL(x...) panic(PRINTK_HEADER x)
420 #else
421 #define PRINT_DEBUG(x...) printk(KERN_DEBUG PRINTK_HEADER x)
422 #define PRINT_INFO(x...) printk(KERN_DEBUG PRINTK_HEADER x)
423 #define PRINT_WARN(x...) printk(KERN_DEBUG PRINTK_HEADER x)
424 #define PRINT_ERR(x...) printk(KERN_DEBUG PRINTK_HEADER x)
425 #define PRINT_FATAL(x...) printk(KERN_DEBUG PRINTK_HEADER x)
426 #endif /* DASD_DEBUG */
427
428 #endif /* _ASM_S390_DEBUG_H */
429