xref: /linux/arch/s390/include/asm/debug.h (revision be709d48329a500621d2a05835283150ae137b45)
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 void debug_stop_all(void);
111 
112 static inline bool debug_level_enabled(debug_info_t *id, int level)
113 {
114 	return level <= id->level;
115 }
116 
117 static inline debug_entry_t *debug_event(debug_info_t *id, int level,
118 					 void *data, int length)
119 {
120 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
121 		return NULL;
122 	return debug_event_common(id, level, data, length);
123 }
124 
125 static inline debug_entry_t *debug_int_event(debug_info_t *id, int level,
126 					     unsigned int tag)
127 {
128 	unsigned int t = tag;
129 
130 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
131 		return NULL;
132 	return debug_event_common(id, level, &t, sizeof(unsigned int));
133 }
134 
135 static inline debug_entry_t *debug_long_event(debug_info_t *id, int level,
136 					      unsigned long tag)
137 {
138 	unsigned long t = tag;
139 
140 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
141 		return NULL;
142 	return debug_event_common(id, level, &t, sizeof(unsigned long));
143 }
144 
145 static inline debug_entry_t *debug_text_event(debug_info_t *id, int level,
146 					      const char *txt)
147 {
148 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
149 		return NULL;
150 	return debug_event_common(id, level, txt, strlen(txt));
151 }
152 
153 /*
154  * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
155  * stored in the s390dbf. See Documentation/s390/s390dbf.txt for more details!
156  */
157 extern debug_entry_t *
158 __debug_sprintf_event(debug_info_t *id, int level, char *string, ...)
159 	__attribute__ ((format(printf, 3, 4)));
160 
161 #define debug_sprintf_event(_id, _level, _fmt, ...)			\
162 ({									\
163 	debug_entry_t *__ret;						\
164 	debug_info_t *__id = _id;					\
165 	int __level = _level;						\
166 									\
167 	if ((!__id) || (__level > __id->level))				\
168 		__ret = NULL;						\
169 	else								\
170 		__ret = __debug_sprintf_event(__id, __level,		\
171 					      _fmt, ## __VA_ARGS__);	\
172 	__ret;								\
173 })
174 
175 static inline debug_entry_t *debug_exception(debug_info_t *id, int level,
176 					     void *data, int length)
177 {
178 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
179 		return NULL;
180 	return debug_exception_common(id, level, data, length);
181 }
182 
183 static inline debug_entry_t *debug_int_exception(debug_info_t *id, int level,
184 						 unsigned int tag)
185 {
186 	unsigned int t = tag;
187 
188 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
189 		return NULL;
190 	return debug_exception_common(id, level, &t, sizeof(unsigned int));
191 }
192 
193 static inline debug_entry_t *debug_long_exception (debug_info_t *id, int level,
194 						   unsigned long tag)
195 {
196 	unsigned long t = tag;
197 
198 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
199 		return NULL;
200 	return debug_exception_common(id, level, &t, sizeof(unsigned long));
201 }
202 
203 static inline debug_entry_t *debug_text_exception(debug_info_t *id, int level,
204 						  const char *txt)
205 {
206 	if ((!id) || (level > id->level) || (id->pages_per_area == 0))
207 		return NULL;
208 	return debug_exception_common(id, level, txt, strlen(txt));
209 }
210 
211 /*
212  * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
213  * stored in the s390dbf. See Documentation/s390/s390dbf.txt for more details!
214  */
215 extern debug_entry_t *
216 __debug_sprintf_exception(debug_info_t *id, int level, char *string, ...)
217 	__attribute__ ((format(printf, 3, 4)));
218 
219 #define debug_sprintf_exception(_id, _level, _fmt, ...)			\
220 ({									\
221 	debug_entry_t *__ret;						\
222 	debug_info_t *__id = _id;					\
223 	int __level = _level;						\
224 									\
225 	if ((!__id) || (__level > __id->level))				\
226 		__ret = NULL;						\
227 	else								\
228 		__ret = __debug_sprintf_exception(__id, __level,	\
229 						  _fmt, ## __VA_ARGS__);\
230 	__ret;								\
231 })
232 
233 int debug_register_view(debug_info_t *id, struct debug_view *view);
234 int debug_unregister_view(debug_info_t *id, struct debug_view *view);
235 
236 /*
237    define the debug levels:
238    - 0 No debugging output to console or syslog
239    - 1 Log internal errors to syslog, ignore check conditions
240    - 2 Log internal errors and check conditions to syslog
241    - 3 Log internal errors to console, log check conditions to syslog
242    - 4 Log internal errors and check conditions to console
243    - 5 panic on internal errors, log check conditions to console
244    - 6 panic on both, internal errors and check conditions
245  */
246 
247 #ifndef DEBUG_LEVEL
248 #define DEBUG_LEVEL 4
249 #endif
250 
251 #define INTERNAL_ERRMSG(x,y...) "E" __FILE__ "%d: " x, __LINE__, y
252 #define INTERNAL_WRNMSG(x,y...) "W" __FILE__ "%d: " x, __LINE__, y
253 #define INTERNAL_INFMSG(x,y...) "I" __FILE__ "%d: " x, __LINE__, y
254 #define INTERNAL_DEBMSG(x,y...) "D" __FILE__ "%d: " x, __LINE__, y
255 
256 #if DEBUG_LEVEL > 0
257 #define PRINT_DEBUG(x...)	printk(KERN_DEBUG PRINTK_HEADER x)
258 #define PRINT_INFO(x...)	printk(KERN_INFO PRINTK_HEADER x)
259 #define PRINT_WARN(x...)	printk(KERN_WARNING PRINTK_HEADER x)
260 #define PRINT_ERR(x...)		printk(KERN_ERR PRINTK_HEADER x)
261 #define PRINT_FATAL(x...)	panic(PRINTK_HEADER x)
262 #else
263 #define PRINT_DEBUG(x...)	printk(KERN_DEBUG PRINTK_HEADER x)
264 #define PRINT_INFO(x...)	printk(KERN_DEBUG PRINTK_HEADER x)
265 #define PRINT_WARN(x...)	printk(KERN_DEBUG PRINTK_HEADER x)
266 #define PRINT_ERR(x...)		printk(KERN_DEBUG PRINTK_HEADER x)
267 #define PRINT_FATAL(x...)	printk(KERN_DEBUG PRINTK_HEADER x)
268 #endif /* DASD_DEBUG */
269 
270 #endif /* DEBUG_H */
271