xref: /openbmc/linux/arch/s390/include/asm/debug.h (revision ce746d43)
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 <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	   2  /* version of debug feature */
30 
31 struct __debug_entry {
32 	union {
33 		struct {
34 			unsigned long clock	: 52;
35 			unsigned long exception	:  1;
36 			unsigned long level	:  3;
37 			unsigned long cpuid	:  8;
38 		} fields;
39 		unsigned long stck;
40 	} id;
41 	void *caller;
42 } __packed;
43 
44 typedef struct __debug_entry debug_entry_t;
45 
46 struct debug_view;
47 
48 typedef struct debug_info {
49 	struct debug_info *next;
50 	struct debug_info *prev;
51 	refcount_t ref_count;
52 	spinlock_t lock;
53 	int level;
54 	int nr_areas;
55 	int pages_per_area;
56 	int buf_size;
57 	int entry_size;
58 	debug_entry_t ***areas;
59 	int active_area;
60 	int *active_pages;
61 	int *active_entries;
62 	struct dentry *debugfs_root_entry;
63 	struct dentry *debugfs_entries[DEBUG_MAX_VIEWS];
64 	struct debug_view *views[DEBUG_MAX_VIEWS];
65 	char name[DEBUG_MAX_NAME_LEN];
66 	umode_t mode;
67 } debug_info_t;
68 
69 typedef int (debug_header_proc_t) (debug_info_t *id,
70 				   struct debug_view *view,
71 				   int area,
72 				   debug_entry_t *entry,
73 				   char *out_buf);
74 
75 typedef int (debug_format_proc_t) (debug_info_t *id,
76 				   struct debug_view *view, char *out_buf,
77 				   const char *in_buf);
78 typedef int (debug_prolog_proc_t) (debug_info_t *id,
79 				   struct debug_view *view,
80 				   char *out_buf);
81 typedef int (debug_input_proc_t) (debug_info_t *id,
82 				  struct debug_view *view,
83 				  struct file *file,
84 				  const char __user *user_buf,
85 				  size_t in_buf_size, loff_t *offset);
86 
87 int debug_dflt_header_fn(debug_info_t *id, struct debug_view *view,
88 			 int area, debug_entry_t *entry, char *out_buf);
89 
90 struct debug_view {
91 	char name[DEBUG_MAX_NAME_LEN];
92 	debug_prolog_proc_t *prolog_proc;
93 	debug_header_proc_t *header_proc;
94 	debug_format_proc_t *format_proc;
95 	debug_input_proc_t  *input_proc;
96 	void		    *private_data;
97 };
98 
99 extern struct debug_view debug_hex_ascii_view;
100 extern struct debug_view debug_sprintf_view;
101 
102 /* do NOT use the _common functions */
103 
104 debug_entry_t *debug_event_common(debug_info_t *id, int level,
105 				  const void *data, int length);
106 
107 debug_entry_t *debug_exception_common(debug_info_t *id, int level,
108 				      const void *data, int length);
109 
110 /* Debug Feature API: */
111 
112 debug_info_t *debug_register(const char *name, int pages, int nr_areas,
113 			     int buf_size);
114 
115 debug_info_t *debug_register_mode(const char *name, int pages, int nr_areas,
116 				  int buf_size, umode_t mode, uid_t uid,
117 				  gid_t gid);
118 
119 void debug_unregister(debug_info_t *id);
120 
121 void debug_set_level(debug_info_t *id, int new_level);
122 
123 void debug_set_critical(void);
124 
125 void debug_stop_all(void);
126 
127 /**
128  * debug_level_enabled() - Returns true if debug events for the specified
129  *			   level would be logged. Otherwise returns false.
130  *
131  * @id:		handle for debug log
132  * @level:	debug level
133  *
134  * Return:
135  * - %true if level is less or equal to the current debug level.
136  */
137 static inline bool debug_level_enabled(debug_info_t *id, int level)
138 {
139 	return level <= id->level;
140 }
141 
142 /**
143  * debug_event() - writes binary debug entry to active debug area
144  *		   (if level <= actual debug level)
145  *
146  * @id:		handle for debug log
147  * @level:	debug level
148  * @data:	pointer to data for debug entry
149  * @length:	length of data in bytes
150  *
151  * Return:
152  * - Address of written debug entry
153  * - %NULL if error
154  */
155 static inline debug_entry_t *debug_event(debug_info_t *id, int level,
156 					 void *data, int length)
157 {
158 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
159 		return NULL;
160 	return debug_event_common(id, level, data, length);
161 }
162 
163 /**
164  * debug_int_event() - writes unsigned integer debug entry to active debug area
165  *		       (if level <= actual debug level)
166  *
167  * @id:		handle for debug log
168  * @level:	debug level
169  * @tag:	integer value for debug entry
170  *
171  * Return:
172  * - Address of written debug entry
173  * - %NULL if error
174  */
175 static inline debug_entry_t *debug_int_event(debug_info_t *id, int level,
176 					     unsigned int tag)
177 {
178 	unsigned int t = tag;
179 
180 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
181 		return NULL;
182 	return debug_event_common(id, level, &t, sizeof(unsigned int));
183 }
184 
185 /**
186  * debug_long_event() - writes unsigned long debug entry to active debug area
187  *		       (if level <= actual debug level)
188  *
189  * @id:		handle for debug log
190  * @level:	debug level
191  * @tag:	long integer value for debug entry
192  *
193  * Return:
194  * - Address of written debug entry
195  * - %NULL if error
196  */
197 static inline debug_entry_t *debug_long_event(debug_info_t *id, int level,
198 					      unsigned long tag)
199 {
200 	unsigned long t = tag;
201 
202 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
203 		return NULL;
204 	return debug_event_common(id, level, &t, sizeof(unsigned long));
205 }
206 
207 /**
208  * debug_text_event() - writes string debug entry in ascii format to active
209  *			debug area (if level <= actual debug level)
210  *
211  * @id:		handle for debug log
212  * @level:	debug level
213  * @txt:	string for debug entry
214  *
215  * Return:
216  * - Address of written debug entry
217  * - %NULL if error
218  */
219 static inline debug_entry_t *debug_text_event(debug_info_t *id, int level,
220 					      const char *txt)
221 {
222 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
223 		return NULL;
224 	return debug_event_common(id, level, txt, strlen(txt));
225 }
226 
227 /*
228  * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
229  * stored in the s390dbf. See Documentation/s390/s390dbf.rst for more details!
230  */
231 extern debug_entry_t *
232 __debug_sprintf_event(debug_info_t *id, int level, char *string, ...)
233 	__attribute__ ((format(printf, 3, 4)));
234 
235 /**
236  * debug_sprintf_event() - writes debug entry with format string
237  *			   and varargs (longs) to active debug area
238  *			   (if level $<=$ actual debug level).
239  *
240  * @_id:	handle for debug log
241  * @_level:	debug level
242  * @_fmt:	format string for debug entry
243  * @...:	varargs used as in sprintf()
244  *
245  * Return:
246  * - Address of written debug entry
247  * - %NULL if error
248  *
249  * floats and long long datatypes cannot be used as varargs.
250  */
251 #define debug_sprintf_event(_id, _level, _fmt, ...)			\
252 ({									\
253 	debug_entry_t *__ret;						\
254 	debug_info_t *__id = _id;					\
255 	int __level = _level;						\
256 									\
257 	if ((!__id) || (__level > __id->level))				\
258 		__ret = NULL;						\
259 	else								\
260 		__ret = __debug_sprintf_event(__id, __level,		\
261 					      _fmt, ## __VA_ARGS__);	\
262 	__ret;								\
263 })
264 
265 /**
266  * debug_exception() - writes binary debug entry to active debug area
267  *		       (if level <= actual debug level)
268  *		       and switches to next debug area
269  *
270  * @id:		handle for debug log
271  * @level:	debug level
272  * @data:	pointer to data for debug entry
273  * @length:	length of data in bytes
274  *
275  * Return:
276  * - Address of written debug entry
277  * - %NULL if error
278  */
279 static inline debug_entry_t *debug_exception(debug_info_t *id, int level,
280 					     void *data, int length)
281 {
282 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
283 		return NULL;
284 	return debug_exception_common(id, level, data, length);
285 }
286 
287 /**
288  * debug_int_exception() - writes unsigned int debug entry to active debug area
289  *			   (if level <= actual debug level)
290  *			   and switches to next debug area
291  *
292  * @id:		handle for debug log
293  * @level:	debug level
294  * @tag:	integer value for debug entry
295  *
296  * Return:
297  * - Address of written debug entry
298  * - %NULL if error
299  */
300 static inline debug_entry_t *debug_int_exception(debug_info_t *id, int level,
301 						 unsigned int tag)
302 {
303 	unsigned int t = tag;
304 
305 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
306 		return NULL;
307 	return debug_exception_common(id, level, &t, sizeof(unsigned int));
308 }
309 
310 /**
311  * debug_long_exception() - writes long debug entry to active debug area
312  *			   (if level <= actual debug level)
313  *			   and switches to next debug area
314  *
315  * @id:		handle for debug log
316  * @level:	debug level
317  * @tag:	long integer value for debug entry
318  *
319  * Return:
320  * - Address of written debug entry
321  * - %NULL if error
322  */
323 static inline debug_entry_t *debug_long_exception (debug_info_t *id, int level,
324 						   unsigned long tag)
325 {
326 	unsigned long t = tag;
327 
328 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
329 		return NULL;
330 	return debug_exception_common(id, level, &t, sizeof(unsigned long));
331 }
332 
333 /**
334  * debug_text_exception() - writes string debug entry in ascii format to active
335  *			    debug area (if level <= actual debug level)
336  *			    and switches to next debug area
337  * area
338  *
339  * @id:	handle for debug log
340  * @level:	debug level
341  * @txt:	string for debug entry
342  *
343  * Return:
344  * - Address of written debug entry
345  * - %NULL if error
346  */
347 static inline debug_entry_t *debug_text_exception(debug_info_t *id, int level,
348 						  const char *txt)
349 {
350 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
351 		return NULL;
352 	return debug_exception_common(id, level, txt, strlen(txt));
353 }
354 
355 /*
356  * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
357  * stored in the s390dbf. See Documentation/s390/s390dbf.rst for more details!
358  */
359 extern debug_entry_t *
360 __debug_sprintf_exception(debug_info_t *id, int level, char *string, ...)
361 	__attribute__ ((format(printf, 3, 4)));
362 
363 
364 /**
365  * debug_sprintf_exception() - writes debug entry with format string and
366  *			       varargs (longs) to active debug area
367  *			       (if level <= actual debug level)
368  *			       and switches to next debug area.
369  *
370  * @_id:	handle for debug log
371  * @_level:	debug level
372  * @_fmt:	format string for debug entry
373  * @...:	varargs used as in sprintf()
374  *
375  * Return:
376  * - Address of written debug entry
377  * - %NULL if error
378  *
379  * floats and long long datatypes cannot be used as varargs.
380  */
381 #define debug_sprintf_exception(_id, _level, _fmt, ...)			\
382 ({									\
383 	debug_entry_t *__ret;						\
384 	debug_info_t *__id = _id;					\
385 	int __level = _level;						\
386 									\
387 	if ((!__id) || (__level > __id->level))				\
388 		__ret = NULL;						\
389 	else								\
390 		__ret = __debug_sprintf_exception(__id, __level,	\
391 						  _fmt, ## __VA_ARGS__);\
392 	__ret;								\
393 })
394 
395 int debug_register_view(debug_info_t *id, struct debug_view *view);
396 
397 int debug_unregister_view(debug_info_t *id, struct debug_view *view);
398 
399 /*
400    define the debug levels:
401    - 0 No debugging output to console or syslog
402    - 1 Log internal errors to syslog, ignore check conditions
403    - 2 Log internal errors and check conditions to syslog
404    - 3 Log internal errors to console, log check conditions to syslog
405    - 4 Log internal errors and check conditions to console
406    - 5 panic on internal errors, log check conditions to console
407    - 6 panic on both, internal errors and check conditions
408  */
409 
410 #ifndef DEBUG_LEVEL
411 #define DEBUG_LEVEL 4
412 #endif
413 
414 #define INTERNAL_ERRMSG(x,y...) "E" __FILE__ "%d: " x, __LINE__, y
415 #define INTERNAL_WRNMSG(x,y...) "W" __FILE__ "%d: " x, __LINE__, y
416 #define INTERNAL_INFMSG(x,y...) "I" __FILE__ "%d: " x, __LINE__, y
417 #define INTERNAL_DEBMSG(x,y...) "D" __FILE__ "%d: " x, __LINE__, y
418 
419 #if DEBUG_LEVEL > 0
420 #define PRINT_DEBUG(x...)	printk(KERN_DEBUG PRINTK_HEADER x)
421 #define PRINT_INFO(x...)	printk(KERN_INFO PRINTK_HEADER x)
422 #define PRINT_WARN(x...)	printk(KERN_WARNING PRINTK_HEADER x)
423 #define PRINT_ERR(x...)		printk(KERN_ERR PRINTK_HEADER x)
424 #define PRINT_FATAL(x...)	panic(PRINTK_HEADER x)
425 #else
426 #define PRINT_DEBUG(x...)	printk(KERN_DEBUG PRINTK_HEADER x)
427 #define PRINT_INFO(x...)	printk(KERN_DEBUG PRINTK_HEADER x)
428 #define PRINT_WARN(x...)	printk(KERN_DEBUG PRINTK_HEADER x)
429 #define PRINT_ERR(x...)		printk(KERN_DEBUG PRINTK_HEADER x)
430 #define PRINT_FATAL(x...)	printk(KERN_DEBUG PRINTK_HEADER x)
431 #endif /* DASD_DEBUG */
432 
433 #endif /* DEBUG_H */
434