arch/s390/include/asm/debug.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  *   S/390 debug facility
   4  *
   5  *    Copyright IBM Corp. 1999, 2020
   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    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  */
 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  */
 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  */
 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  */
 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  */
 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  */
 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  */
 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  */
 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  */
 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 /* DEBUG_H */