1 /* 2 * arch/s390/kernel/debug.c 3 * S/390 debug facility 4 * 5 * Copyright (C) 1999, 2000 IBM Deutschland Entwicklung GmbH, 6 * IBM Corporation 7 * Author(s): Michael Holzheu (holzheu@de.ibm.com), 8 * Holger Smolinski (Holger.Smolinski@de.ibm.com) 9 * 10 * Bugreports to: <Linux390@de.ibm.com> 11 */ 12 13 #include <linux/stddef.h> 14 #include <linux/kernel.h> 15 #include <linux/errno.h> 16 #include <linux/slab.h> 17 #include <linux/ctype.h> 18 #include <linux/sysctl.h> 19 #include <asm/uaccess.h> 20 #include <linux/module.h> 21 #include <linux/init.h> 22 #include <linux/fs.h> 23 #include <linux/debugfs.h> 24 25 #include <asm/debug.h> 26 27 #define DEBUG_PROLOG_ENTRY -1 28 29 #define ALL_AREAS 0 /* copy all debug areas */ 30 #define NO_AREAS 1 /* copy no debug areas */ 31 32 /* typedefs */ 33 34 typedef struct file_private_info { 35 loff_t offset; /* offset of last read in file */ 36 int act_area; /* number of last formated area */ 37 int act_page; /* act page in given area */ 38 int act_entry; /* last formated entry (offset */ 39 /* relative to beginning of last */ 40 /* formated page) */ 41 size_t act_entry_offset; /* up to this offset we copied */ 42 /* in last read the last formated */ 43 /* entry to userland */ 44 char temp_buf[2048]; /* buffer for output */ 45 debug_info_t *debug_info_org; /* original debug information */ 46 debug_info_t *debug_info_snap; /* snapshot of debug information */ 47 struct debug_view *view; /* used view of debug info */ 48 } file_private_info_t; 49 50 typedef struct 51 { 52 char *string; 53 /* 54 * This assumes that all args are converted into longs 55 * on L/390 this is the case for all types of parameter 56 * except of floats, and long long (32 bit) 57 * 58 */ 59 long args[0]; 60 } debug_sprintf_entry_t; 61 62 63 extern void tod_to_timeval(uint64_t todval, struct timespec *xtime); 64 65 /* internal function prototyes */ 66 67 static int debug_init(void); 68 static ssize_t debug_output(struct file *file, char __user *user_buf, 69 size_t user_len, loff_t * offset); 70 static ssize_t debug_input(struct file *file, const char __user *user_buf, 71 size_t user_len, loff_t * offset); 72 static int debug_open(struct inode *inode, struct file *file); 73 static int debug_close(struct inode *inode, struct file *file); 74 static debug_info_t* debug_info_create(char *name, int pages_per_area, 75 int nr_areas, int buf_size, mode_t mode); 76 static void debug_info_get(debug_info_t *); 77 static void debug_info_put(debug_info_t *); 78 static int debug_prolog_level_fn(debug_info_t * id, 79 struct debug_view *view, char *out_buf); 80 static int debug_input_level_fn(debug_info_t * id, struct debug_view *view, 81 struct file *file, const char __user *user_buf, 82 size_t user_buf_size, loff_t * offset); 83 static int debug_prolog_pages_fn(debug_info_t * id, 84 struct debug_view *view, char *out_buf); 85 static int debug_input_pages_fn(debug_info_t * id, struct debug_view *view, 86 struct file *file, const char __user *user_buf, 87 size_t user_buf_size, loff_t * offset); 88 static int debug_input_flush_fn(debug_info_t * id, struct debug_view *view, 89 struct file *file, const char __user *user_buf, 90 size_t user_buf_size, loff_t * offset); 91 static int debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view, 92 char *out_buf, const char *in_buf); 93 static int debug_raw_format_fn(debug_info_t * id, 94 struct debug_view *view, char *out_buf, 95 const char *in_buf); 96 static int debug_raw_header_fn(debug_info_t * id, struct debug_view *view, 97 int area, debug_entry_t * entry, char *out_buf); 98 99 static int debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view, 100 char *out_buf, debug_sprintf_entry_t *curr_event); 101 102 /* globals */ 103 104 struct debug_view debug_raw_view = { 105 "raw", 106 NULL, 107 &debug_raw_header_fn, 108 &debug_raw_format_fn, 109 NULL, 110 NULL 111 }; 112 113 struct debug_view debug_hex_ascii_view = { 114 "hex_ascii", 115 NULL, 116 &debug_dflt_header_fn, 117 &debug_hex_ascii_format_fn, 118 NULL, 119 NULL 120 }; 121 122 static struct debug_view debug_level_view = { 123 "level", 124 &debug_prolog_level_fn, 125 NULL, 126 NULL, 127 &debug_input_level_fn, 128 NULL 129 }; 130 131 static struct debug_view debug_pages_view = { 132 "pages", 133 &debug_prolog_pages_fn, 134 NULL, 135 NULL, 136 &debug_input_pages_fn, 137 NULL 138 }; 139 140 static struct debug_view debug_flush_view = { 141 "flush", 142 NULL, 143 NULL, 144 NULL, 145 &debug_input_flush_fn, 146 NULL 147 }; 148 149 struct debug_view debug_sprintf_view = { 150 "sprintf", 151 NULL, 152 &debug_dflt_header_fn, 153 (debug_format_proc_t*)&debug_sprintf_format_fn, 154 NULL, 155 NULL 156 }; 157 158 /* used by dump analysis tools to determine version of debug feature */ 159 static unsigned int __used debug_feature_version = __DEBUG_FEATURE_VERSION; 160 161 /* static globals */ 162 163 static debug_info_t *debug_area_first = NULL; 164 static debug_info_t *debug_area_last = NULL; 165 static DEFINE_MUTEX(debug_mutex); 166 167 static int initialized; 168 169 static const struct file_operations debug_file_ops = { 170 .owner = THIS_MODULE, 171 .read = debug_output, 172 .write = debug_input, 173 .open = debug_open, 174 .release = debug_close, 175 }; 176 177 static struct dentry *debug_debugfs_root_entry; 178 179 /* functions */ 180 181 /* 182 * debug_areas_alloc 183 * - Debug areas are implemented as a threedimensonal array: 184 * areas[areanumber][pagenumber][pageoffset] 185 */ 186 187 static debug_entry_t*** 188 debug_areas_alloc(int pages_per_area, int nr_areas) 189 { 190 debug_entry_t*** areas; 191 int i,j; 192 193 areas = kmalloc(nr_areas * 194 sizeof(debug_entry_t**), 195 GFP_KERNEL); 196 if (!areas) 197 goto fail_malloc_areas; 198 for (i = 0; i < nr_areas; i++) { 199 areas[i] = kmalloc(pages_per_area * 200 sizeof(debug_entry_t*),GFP_KERNEL); 201 if (!areas[i]) { 202 goto fail_malloc_areas2; 203 } 204 for(j = 0; j < pages_per_area; j++) { 205 areas[i][j] = kzalloc(PAGE_SIZE, GFP_KERNEL); 206 if(!areas[i][j]) { 207 for(j--; j >=0 ; j--) { 208 kfree(areas[i][j]); 209 } 210 kfree(areas[i]); 211 goto fail_malloc_areas2; 212 } 213 } 214 } 215 return areas; 216 217 fail_malloc_areas2: 218 for(i--; i >= 0; i--){ 219 for(j=0; j < pages_per_area;j++){ 220 kfree(areas[i][j]); 221 } 222 kfree(areas[i]); 223 } 224 kfree(areas); 225 fail_malloc_areas: 226 return NULL; 227 228 } 229 230 231 /* 232 * debug_info_alloc 233 * - alloc new debug-info 234 */ 235 236 static debug_info_t* 237 debug_info_alloc(char *name, int pages_per_area, int nr_areas, int buf_size, 238 int level, int mode) 239 { 240 debug_info_t* rc; 241 242 /* alloc everything */ 243 244 rc = kmalloc(sizeof(debug_info_t), GFP_KERNEL); 245 if(!rc) 246 goto fail_malloc_rc; 247 rc->active_entries = kcalloc(nr_areas, sizeof(int), GFP_KERNEL); 248 if(!rc->active_entries) 249 goto fail_malloc_active_entries; 250 rc->active_pages = kcalloc(nr_areas, sizeof(int), GFP_KERNEL); 251 if(!rc->active_pages) 252 goto fail_malloc_active_pages; 253 if((mode == ALL_AREAS) && (pages_per_area != 0)){ 254 rc->areas = debug_areas_alloc(pages_per_area, nr_areas); 255 if(!rc->areas) 256 goto fail_malloc_areas; 257 } else { 258 rc->areas = NULL; 259 } 260 261 /* initialize members */ 262 263 spin_lock_init(&rc->lock); 264 rc->pages_per_area = pages_per_area; 265 rc->nr_areas = nr_areas; 266 rc->active_area = 0; 267 rc->level = level; 268 rc->buf_size = buf_size; 269 rc->entry_size = sizeof(debug_entry_t) + buf_size; 270 strlcpy(rc->name, name, sizeof(rc->name)); 271 memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *)); 272 memset(rc->debugfs_entries, 0 ,DEBUG_MAX_VIEWS * 273 sizeof(struct dentry*)); 274 atomic_set(&(rc->ref_count), 0); 275 276 return rc; 277 278 fail_malloc_areas: 279 kfree(rc->active_pages); 280 fail_malloc_active_pages: 281 kfree(rc->active_entries); 282 fail_malloc_active_entries: 283 kfree(rc); 284 fail_malloc_rc: 285 return NULL; 286 } 287 288 /* 289 * debug_areas_free 290 * - free all debug areas 291 */ 292 293 static void 294 debug_areas_free(debug_info_t* db_info) 295 { 296 int i,j; 297 298 if(!db_info->areas) 299 return; 300 for (i = 0; i < db_info->nr_areas; i++) { 301 for(j = 0; j < db_info->pages_per_area; j++) { 302 kfree(db_info->areas[i][j]); 303 } 304 kfree(db_info->areas[i]); 305 } 306 kfree(db_info->areas); 307 db_info->areas = NULL; 308 } 309 310 /* 311 * debug_info_free 312 * - free memory debug-info 313 */ 314 315 static void 316 debug_info_free(debug_info_t* db_info){ 317 debug_areas_free(db_info); 318 kfree(db_info->active_entries); 319 kfree(db_info->active_pages); 320 kfree(db_info); 321 } 322 323 /* 324 * debug_info_create 325 * - create new debug-info 326 */ 327 328 static debug_info_t* 329 debug_info_create(char *name, int pages_per_area, int nr_areas, int buf_size, 330 mode_t mode) 331 { 332 debug_info_t* rc; 333 334 rc = debug_info_alloc(name, pages_per_area, nr_areas, buf_size, 335 DEBUG_DEFAULT_LEVEL, ALL_AREAS); 336 if(!rc) 337 goto out; 338 339 rc->mode = mode & ~S_IFMT; 340 341 /* create root directory */ 342 rc->debugfs_root_entry = debugfs_create_dir(rc->name, 343 debug_debugfs_root_entry); 344 345 /* append new element to linked list */ 346 if (!debug_area_first) { 347 /* first element in list */ 348 debug_area_first = rc; 349 rc->prev = NULL; 350 } else { 351 /* append element to end of list */ 352 debug_area_last->next = rc; 353 rc->prev = debug_area_last; 354 } 355 debug_area_last = rc; 356 rc->next = NULL; 357 358 debug_info_get(rc); 359 out: 360 return rc; 361 } 362 363 /* 364 * debug_info_copy 365 * - copy debug-info 366 */ 367 368 static debug_info_t* 369 debug_info_copy(debug_info_t* in, int mode) 370 { 371 int i,j; 372 debug_info_t* rc; 373 unsigned long flags; 374 375 /* get a consistent copy of the debug areas */ 376 do { 377 rc = debug_info_alloc(in->name, in->pages_per_area, 378 in->nr_areas, in->buf_size, in->level, mode); 379 spin_lock_irqsave(&in->lock, flags); 380 if(!rc) 381 goto out; 382 /* has something changed in the meantime ? */ 383 if((rc->pages_per_area == in->pages_per_area) && 384 (rc->nr_areas == in->nr_areas)) { 385 break; 386 } 387 spin_unlock_irqrestore(&in->lock, flags); 388 debug_info_free(rc); 389 } while (1); 390 391 if(!rc || (mode == NO_AREAS)) 392 goto out; 393 394 for(i = 0; i < in->nr_areas; i++){ 395 for(j = 0; j < in->pages_per_area; j++) { 396 memcpy(rc->areas[i][j], in->areas[i][j],PAGE_SIZE); 397 } 398 } 399 out: 400 spin_unlock_irqrestore(&in->lock, flags); 401 return rc; 402 } 403 404 /* 405 * debug_info_get 406 * - increments reference count for debug-info 407 */ 408 409 static void 410 debug_info_get(debug_info_t * db_info) 411 { 412 if (db_info) 413 atomic_inc(&db_info->ref_count); 414 } 415 416 /* 417 * debug_info_put: 418 * - decreases reference count for debug-info and frees it if necessary 419 */ 420 421 static void 422 debug_info_put(debug_info_t *db_info) 423 { 424 int i; 425 426 if (!db_info) 427 return; 428 if (atomic_dec_and_test(&db_info->ref_count)) { 429 for (i = 0; i < DEBUG_MAX_VIEWS; i++) { 430 if (!db_info->views[i]) 431 continue; 432 debugfs_remove(db_info->debugfs_entries[i]); 433 } 434 debugfs_remove(db_info->debugfs_root_entry); 435 if(db_info == debug_area_first) 436 debug_area_first = db_info->next; 437 if(db_info == debug_area_last) 438 debug_area_last = db_info->prev; 439 if(db_info->prev) db_info->prev->next = db_info->next; 440 if(db_info->next) db_info->next->prev = db_info->prev; 441 debug_info_free(db_info); 442 } 443 } 444 445 /* 446 * debug_format_entry: 447 * - format one debug entry and return size of formated data 448 */ 449 450 static int 451 debug_format_entry(file_private_info_t *p_info) 452 { 453 debug_info_t *id_snap = p_info->debug_info_snap; 454 struct debug_view *view = p_info->view; 455 debug_entry_t *act_entry; 456 size_t len = 0; 457 if(p_info->act_entry == DEBUG_PROLOG_ENTRY){ 458 /* print prolog */ 459 if (view->prolog_proc) 460 len += view->prolog_proc(id_snap,view,p_info->temp_buf); 461 goto out; 462 } 463 if (!id_snap->areas) /* this is true, if we have a prolog only view */ 464 goto out; /* or if 'pages_per_area' is 0 */ 465 act_entry = (debug_entry_t *) ((char*)id_snap->areas[p_info->act_area] 466 [p_info->act_page] + p_info->act_entry); 467 468 if (act_entry->id.stck == 0LL) 469 goto out; /* empty entry */ 470 if (view->header_proc) 471 len += view->header_proc(id_snap, view, p_info->act_area, 472 act_entry, p_info->temp_buf + len); 473 if (view->format_proc) 474 len += view->format_proc(id_snap, view, p_info->temp_buf + len, 475 DEBUG_DATA(act_entry)); 476 out: 477 return len; 478 } 479 480 /* 481 * debug_next_entry: 482 * - goto next entry in p_info 483 */ 484 485 static inline int 486 debug_next_entry(file_private_info_t *p_info) 487 { 488 debug_info_t *id; 489 490 id = p_info->debug_info_snap; 491 if(p_info->act_entry == DEBUG_PROLOG_ENTRY){ 492 p_info->act_entry = 0; 493 p_info->act_page = 0; 494 goto out; 495 } 496 if(!id->areas) 497 return 1; 498 p_info->act_entry += id->entry_size; 499 /* switch to next page, if we reached the end of the page */ 500 if (p_info->act_entry > (PAGE_SIZE - id->entry_size)){ 501 /* next page */ 502 p_info->act_entry = 0; 503 p_info->act_page += 1; 504 if((p_info->act_page % id->pages_per_area) == 0) { 505 /* next area */ 506 p_info->act_area++; 507 p_info->act_page=0; 508 } 509 if(p_info->act_area >= id->nr_areas) 510 return 1; 511 } 512 out: 513 return 0; 514 } 515 516 /* 517 * debug_output: 518 * - called for user read() 519 * - copies formated debug entries to the user buffer 520 */ 521 522 static ssize_t 523 debug_output(struct file *file, /* file descriptor */ 524 char __user *user_buf, /* user buffer */ 525 size_t len, /* length of buffer */ 526 loff_t *offset) /* offset in the file */ 527 { 528 size_t count = 0; 529 size_t entry_offset; 530 file_private_info_t *p_info; 531 532 p_info = ((file_private_info_t *) file->private_data); 533 if (*offset != p_info->offset) 534 return -EPIPE; 535 if(p_info->act_area >= p_info->debug_info_snap->nr_areas) 536 return 0; 537 entry_offset = p_info->act_entry_offset; 538 while(count < len){ 539 int formatted_line_size; 540 int formatted_line_residue; 541 int user_buf_residue; 542 size_t copy_size; 543 544 formatted_line_size = debug_format_entry(p_info); 545 formatted_line_residue = formatted_line_size - entry_offset; 546 user_buf_residue = len-count; 547 copy_size = min(user_buf_residue, formatted_line_residue); 548 if(copy_size){ 549 if (copy_to_user(user_buf + count, p_info->temp_buf 550 + entry_offset, copy_size)) 551 return -EFAULT; 552 count += copy_size; 553 entry_offset += copy_size; 554 } 555 if(copy_size == formatted_line_residue){ 556 entry_offset = 0; 557 if(debug_next_entry(p_info)) 558 goto out; 559 } 560 } 561 out: 562 p_info->offset = *offset + count; 563 p_info->act_entry_offset = entry_offset; 564 *offset = p_info->offset; 565 return count; 566 } 567 568 /* 569 * debug_input: 570 * - called for user write() 571 * - calls input function of view 572 */ 573 574 static ssize_t 575 debug_input(struct file *file, const char __user *user_buf, size_t length, 576 loff_t *offset) 577 { 578 int rc = 0; 579 file_private_info_t *p_info; 580 581 mutex_lock(&debug_mutex); 582 p_info = ((file_private_info_t *) file->private_data); 583 if (p_info->view->input_proc) 584 rc = p_info->view->input_proc(p_info->debug_info_org, 585 p_info->view, file, user_buf, 586 length, offset); 587 else 588 rc = -EPERM; 589 mutex_unlock(&debug_mutex); 590 return rc; /* number of input characters */ 591 } 592 593 /* 594 * debug_open: 595 * - called for user open() 596 * - copies formated output to private_data area of the file 597 * handle 598 */ 599 600 static int 601 debug_open(struct inode *inode, struct file *file) 602 { 603 int i = 0, rc = 0; 604 file_private_info_t *p_info; 605 debug_info_t *debug_info, *debug_info_snapshot; 606 607 mutex_lock(&debug_mutex); 608 debug_info = file->f_path.dentry->d_inode->i_private; 609 /* find debug view */ 610 for (i = 0; i < DEBUG_MAX_VIEWS; i++) { 611 if (!debug_info->views[i]) 612 continue; 613 else if (debug_info->debugfs_entries[i] == 614 file->f_path.dentry) { 615 goto found; /* found view ! */ 616 } 617 } 618 /* no entry found */ 619 rc = -EINVAL; 620 goto out; 621 622 found: 623 624 /* Make snapshot of current debug areas to get it consistent. */ 625 /* To copy all the areas is only needed, if we have a view which */ 626 /* formats the debug areas. */ 627 628 if(!debug_info->views[i]->format_proc && 629 !debug_info->views[i]->header_proc){ 630 debug_info_snapshot = debug_info_copy(debug_info, NO_AREAS); 631 } else { 632 debug_info_snapshot = debug_info_copy(debug_info, ALL_AREAS); 633 } 634 635 if(!debug_info_snapshot){ 636 rc = -ENOMEM; 637 goto out; 638 } 639 p_info = kmalloc(sizeof(file_private_info_t), 640 GFP_KERNEL); 641 if(!p_info){ 642 if(debug_info_snapshot) 643 debug_info_free(debug_info_snapshot); 644 rc = -ENOMEM; 645 goto out; 646 } 647 p_info->offset = 0; 648 p_info->debug_info_snap = debug_info_snapshot; 649 p_info->debug_info_org = debug_info; 650 p_info->view = debug_info->views[i]; 651 p_info->act_area = 0; 652 p_info->act_page = 0; 653 p_info->act_entry = DEBUG_PROLOG_ENTRY; 654 p_info->act_entry_offset = 0; 655 file->private_data = p_info; 656 debug_info_get(debug_info); 657 out: 658 mutex_unlock(&debug_mutex); 659 return rc; 660 } 661 662 /* 663 * debug_close: 664 * - called for user close() 665 * - deletes private_data area of the file handle 666 */ 667 668 static int 669 debug_close(struct inode *inode, struct file *file) 670 { 671 file_private_info_t *p_info; 672 p_info = (file_private_info_t *) file->private_data; 673 if(p_info->debug_info_snap) 674 debug_info_free(p_info->debug_info_snap); 675 debug_info_put(p_info->debug_info_org); 676 kfree(file->private_data); 677 return 0; /* success */ 678 } 679 680 /* 681 * debug_register_mode: 682 * - Creates and initializes debug area for the caller 683 * The mode parameter allows to specify access rights for the s390dbf files 684 * - Returns handle for debug area 685 */ 686 687 debug_info_t *debug_register_mode(char *name, int pages_per_area, int nr_areas, 688 int buf_size, mode_t mode, uid_t uid, 689 gid_t gid) 690 { 691 debug_info_t *rc = NULL; 692 693 /* Since debugfs currently does not support uid/gid other than root, */ 694 /* we do not allow gid/uid != 0 until we get support for that. */ 695 if ((uid != 0) || (gid != 0)) 696 printk(KERN_WARNING "debug: Warning - Currently only uid/gid " 697 "= 0 are supported. Using root as owner now!"); 698 if (!initialized) 699 BUG(); 700 mutex_lock(&debug_mutex); 701 702 /* create new debug_info */ 703 704 rc = debug_info_create(name, pages_per_area, nr_areas, buf_size, mode); 705 if(!rc) 706 goto out; 707 debug_register_view(rc, &debug_level_view); 708 debug_register_view(rc, &debug_flush_view); 709 debug_register_view(rc, &debug_pages_view); 710 out: 711 if (!rc){ 712 printk(KERN_ERR "debug: debug_register failed for %s\n",name); 713 } 714 mutex_unlock(&debug_mutex); 715 return rc; 716 } 717 EXPORT_SYMBOL(debug_register_mode); 718 719 /* 720 * debug_register: 721 * - creates and initializes debug area for the caller 722 * - returns handle for debug area 723 */ 724 725 debug_info_t *debug_register(char *name, int pages_per_area, int nr_areas, 726 int buf_size) 727 { 728 return debug_register_mode(name, pages_per_area, nr_areas, buf_size, 729 S_IRUSR | S_IWUSR, 0, 0); 730 } 731 732 /* 733 * debug_unregister: 734 * - give back debug area 735 */ 736 737 void 738 debug_unregister(debug_info_t * id) 739 { 740 if (!id) 741 goto out; 742 mutex_lock(&debug_mutex); 743 debug_info_put(id); 744 mutex_unlock(&debug_mutex); 745 746 out: 747 return; 748 } 749 750 /* 751 * debug_set_size: 752 * - set area size (number of pages) and number of areas 753 */ 754 static int 755 debug_set_size(debug_info_t* id, int nr_areas, int pages_per_area) 756 { 757 unsigned long flags; 758 debug_entry_t *** new_areas; 759 int rc=0; 760 761 if(!id || (nr_areas <= 0) || (pages_per_area < 0)) 762 return -EINVAL; 763 if(pages_per_area > 0){ 764 new_areas = debug_areas_alloc(pages_per_area, nr_areas); 765 if(!new_areas) { 766 printk(KERN_WARNING "debug: could not allocate memory "\ 767 "for pagenumber: %i\n",pages_per_area); 768 rc = -ENOMEM; 769 goto out; 770 } 771 } else { 772 new_areas = NULL; 773 } 774 spin_lock_irqsave(&id->lock,flags); 775 debug_areas_free(id); 776 id->areas = new_areas; 777 id->nr_areas = nr_areas; 778 id->pages_per_area = pages_per_area; 779 id->active_area = 0; 780 memset(id->active_entries,0,sizeof(int)*id->nr_areas); 781 memset(id->active_pages, 0, sizeof(int)*id->nr_areas); 782 spin_unlock_irqrestore(&id->lock,flags); 783 printk(KERN_INFO "debug: %s: set new size (%i pages)\n"\ 784 ,id->name, pages_per_area); 785 out: 786 return rc; 787 } 788 789 /* 790 * debug_set_level: 791 * - set actual debug level 792 */ 793 794 void 795 debug_set_level(debug_info_t* id, int new_level) 796 { 797 unsigned long flags; 798 if(!id) 799 return; 800 spin_lock_irqsave(&id->lock,flags); 801 if(new_level == DEBUG_OFF_LEVEL){ 802 id->level = DEBUG_OFF_LEVEL; 803 printk(KERN_INFO "debug: %s: switched off\n",id->name); 804 } else if ((new_level > DEBUG_MAX_LEVEL) || (new_level < 0)) { 805 printk(KERN_INFO 806 "debug: %s: level %i is out of range (%i - %i)\n", 807 id->name, new_level, 0, DEBUG_MAX_LEVEL); 808 } else { 809 id->level = new_level; 810 } 811 spin_unlock_irqrestore(&id->lock,flags); 812 } 813 814 815 /* 816 * proceed_active_entry: 817 * - set active entry to next in the ring buffer 818 */ 819 820 static inline void 821 proceed_active_entry(debug_info_t * id) 822 { 823 if ((id->active_entries[id->active_area] += id->entry_size) 824 > (PAGE_SIZE - id->entry_size)){ 825 id->active_entries[id->active_area] = 0; 826 id->active_pages[id->active_area] = 827 (id->active_pages[id->active_area] + 1) % 828 id->pages_per_area; 829 } 830 } 831 832 /* 833 * proceed_active_area: 834 * - set active area to next in the ring buffer 835 */ 836 837 static inline void 838 proceed_active_area(debug_info_t * id) 839 { 840 id->active_area++; 841 id->active_area = id->active_area % id->nr_areas; 842 } 843 844 /* 845 * get_active_entry: 846 */ 847 848 static inline debug_entry_t* 849 get_active_entry(debug_info_t * id) 850 { 851 return (debug_entry_t *) (((char *) id->areas[id->active_area] 852 [id->active_pages[id->active_area]]) + 853 id->active_entries[id->active_area]); 854 } 855 856 /* 857 * debug_finish_entry: 858 * - set timestamp, caller address, cpu number etc. 859 */ 860 861 static inline void 862 debug_finish_entry(debug_info_t * id, debug_entry_t* active, int level, 863 int exception) 864 { 865 active->id.stck = get_clock(); 866 active->id.fields.cpuid = smp_processor_id(); 867 active->caller = __builtin_return_address(0); 868 active->id.fields.exception = exception; 869 active->id.fields.level = level; 870 proceed_active_entry(id); 871 if(exception) 872 proceed_active_area(id); 873 } 874 875 static int debug_stoppable=1; 876 static int debug_active=1; 877 878 #define CTL_S390DBF_STOPPABLE 5678 879 #define CTL_S390DBF_ACTIVE 5679 880 881 /* 882 * proc handler for the running debug_active sysctl 883 * always allow read, allow write only if debug_stoppable is set or 884 * if debug_active is already off 885 */ 886 static int 887 s390dbf_procactive(ctl_table *table, int write, struct file *filp, 888 void __user *buffer, size_t *lenp, loff_t *ppos) 889 { 890 if (!write || debug_stoppable || !debug_active) 891 return proc_dointvec(table, write, filp, buffer, lenp, ppos); 892 else 893 return 0; 894 } 895 896 897 static struct ctl_table s390dbf_table[] = { 898 { 899 .ctl_name = CTL_S390DBF_STOPPABLE, 900 .procname = "debug_stoppable", 901 .data = &debug_stoppable, 902 .maxlen = sizeof(int), 903 .mode = S_IRUGO | S_IWUSR, 904 .proc_handler = &proc_dointvec, 905 .strategy = &sysctl_intvec, 906 }, 907 { 908 .ctl_name = CTL_S390DBF_ACTIVE, 909 .procname = "debug_active", 910 .data = &debug_active, 911 .maxlen = sizeof(int), 912 .mode = S_IRUGO | S_IWUSR, 913 .proc_handler = &s390dbf_procactive, 914 .strategy = &sysctl_intvec, 915 }, 916 { .ctl_name = 0 } 917 }; 918 919 static struct ctl_table s390dbf_dir_table[] = { 920 { 921 .ctl_name = CTL_S390DBF, 922 .procname = "s390dbf", 923 .maxlen = 0, 924 .mode = S_IRUGO | S_IXUGO, 925 .child = s390dbf_table, 926 }, 927 { .ctl_name = 0 } 928 }; 929 930 static struct ctl_table_header *s390dbf_sysctl_header; 931 932 void 933 debug_stop_all(void) 934 { 935 if (debug_stoppable) 936 debug_active = 0; 937 } 938 939 940 /* 941 * debug_event_common: 942 * - write debug entry with given size 943 */ 944 945 debug_entry_t* 946 debug_event_common(debug_info_t * id, int level, const void *buf, int len) 947 { 948 unsigned long flags; 949 debug_entry_t *active; 950 951 if (!debug_active || !id->areas) 952 return NULL; 953 spin_lock_irqsave(&id->lock, flags); 954 active = get_active_entry(id); 955 memset(DEBUG_DATA(active), 0, id->buf_size); 956 memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size)); 957 debug_finish_entry(id, active, level, 0); 958 spin_unlock_irqrestore(&id->lock, flags); 959 960 return active; 961 } 962 963 /* 964 * debug_exception_common: 965 * - write debug entry with given size and switch to next debug area 966 */ 967 968 debug_entry_t 969 *debug_exception_common(debug_info_t * id, int level, const void *buf, int len) 970 { 971 unsigned long flags; 972 debug_entry_t *active; 973 974 if (!debug_active || !id->areas) 975 return NULL; 976 spin_lock_irqsave(&id->lock, flags); 977 active = get_active_entry(id); 978 memset(DEBUG_DATA(active), 0, id->buf_size); 979 memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size)); 980 debug_finish_entry(id, active, level, 1); 981 spin_unlock_irqrestore(&id->lock, flags); 982 983 return active; 984 } 985 986 /* 987 * counts arguments in format string for sprintf view 988 */ 989 990 static inline int 991 debug_count_numargs(char *string) 992 { 993 int numargs=0; 994 995 while(*string) { 996 if(*string++=='%') 997 numargs++; 998 } 999 return(numargs); 1000 } 1001 1002 /* 1003 * debug_sprintf_event: 1004 */ 1005 1006 debug_entry_t* 1007 debug_sprintf_event(debug_info_t* id, int level,char *string,...) 1008 { 1009 va_list ap; 1010 int numargs,idx; 1011 unsigned long flags; 1012 debug_sprintf_entry_t *curr_event; 1013 debug_entry_t *active; 1014 1015 if((!id) || (level > id->level)) 1016 return NULL; 1017 if (!debug_active || !id->areas) 1018 return NULL; 1019 numargs=debug_count_numargs(string); 1020 1021 spin_lock_irqsave(&id->lock, flags); 1022 active = get_active_entry(id); 1023 curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active); 1024 va_start(ap,string); 1025 curr_event->string=string; 1026 for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++) 1027 curr_event->args[idx]=va_arg(ap,long); 1028 va_end(ap); 1029 debug_finish_entry(id, active, level, 0); 1030 spin_unlock_irqrestore(&id->lock, flags); 1031 1032 return active; 1033 } 1034 1035 /* 1036 * debug_sprintf_exception: 1037 */ 1038 1039 debug_entry_t* 1040 debug_sprintf_exception(debug_info_t* id, int level,char *string,...) 1041 { 1042 va_list ap; 1043 int numargs,idx; 1044 unsigned long flags; 1045 debug_sprintf_entry_t *curr_event; 1046 debug_entry_t *active; 1047 1048 if((!id) || (level > id->level)) 1049 return NULL; 1050 if (!debug_active || !id->areas) 1051 return NULL; 1052 1053 numargs=debug_count_numargs(string); 1054 1055 spin_lock_irqsave(&id->lock, flags); 1056 active = get_active_entry(id); 1057 curr_event=(debug_sprintf_entry_t *)DEBUG_DATA(active); 1058 va_start(ap,string); 1059 curr_event->string=string; 1060 for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++) 1061 curr_event->args[idx]=va_arg(ap,long); 1062 va_end(ap); 1063 debug_finish_entry(id, active, level, 1); 1064 spin_unlock_irqrestore(&id->lock, flags); 1065 1066 return active; 1067 } 1068 1069 /* 1070 * debug_init: 1071 * - is called exactly once to initialize the debug feature 1072 */ 1073 1074 static int 1075 __init debug_init(void) 1076 { 1077 int rc = 0; 1078 1079 s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table); 1080 mutex_lock(&debug_mutex); 1081 debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT,NULL); 1082 printk(KERN_INFO "debug: Initialization complete\n"); 1083 initialized = 1; 1084 mutex_unlock(&debug_mutex); 1085 1086 return rc; 1087 } 1088 1089 /* 1090 * debug_register_view: 1091 */ 1092 1093 int 1094 debug_register_view(debug_info_t * id, struct debug_view *view) 1095 { 1096 int rc = 0; 1097 int i; 1098 unsigned long flags; 1099 mode_t mode; 1100 struct dentry *pde; 1101 1102 if (!id) 1103 goto out; 1104 mode = (id->mode | S_IFREG) & ~S_IXUGO; 1105 if (!(view->prolog_proc || view->format_proc || view->header_proc)) 1106 mode &= ~(S_IRUSR | S_IRGRP | S_IROTH); 1107 if (!view->input_proc) 1108 mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH); 1109 pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry, 1110 id , &debug_file_ops); 1111 if (!pde){ 1112 printk(KERN_WARNING "debug: debugfs_create_file() failed!"\ 1113 " Cannot register view %s/%s\n", id->name,view->name); 1114 rc = -1; 1115 goto out; 1116 } 1117 spin_lock_irqsave(&id->lock, flags); 1118 for (i = 0; i < DEBUG_MAX_VIEWS; i++) { 1119 if (!id->views[i]) 1120 break; 1121 } 1122 if (i == DEBUG_MAX_VIEWS) { 1123 printk(KERN_WARNING "debug: cannot register view %s/%s\n", 1124 id->name,view->name); 1125 printk(KERN_WARNING 1126 "debug: maximum number of views reached (%i)!\n", i); 1127 debugfs_remove(pde); 1128 rc = -1; 1129 } else { 1130 id->views[i] = view; 1131 id->debugfs_entries[i] = pde; 1132 } 1133 spin_unlock_irqrestore(&id->lock, flags); 1134 out: 1135 return rc; 1136 } 1137 1138 /* 1139 * debug_unregister_view: 1140 */ 1141 1142 int 1143 debug_unregister_view(debug_info_t * id, struct debug_view *view) 1144 { 1145 int rc = 0; 1146 int i; 1147 unsigned long flags; 1148 1149 if (!id) 1150 goto out; 1151 spin_lock_irqsave(&id->lock, flags); 1152 for (i = 0; i < DEBUG_MAX_VIEWS; i++) { 1153 if (id->views[i] == view) 1154 break; 1155 } 1156 if (i == DEBUG_MAX_VIEWS) 1157 rc = -1; 1158 else { 1159 debugfs_remove(id->debugfs_entries[i]); 1160 id->views[i] = NULL; 1161 rc = 0; 1162 } 1163 spin_unlock_irqrestore(&id->lock, flags); 1164 out: 1165 return rc; 1166 } 1167 1168 static inline char * 1169 debug_get_user_string(const char __user *user_buf, size_t user_len) 1170 { 1171 char* buffer; 1172 1173 buffer = kmalloc(user_len + 1, GFP_KERNEL); 1174 if (!buffer) 1175 return ERR_PTR(-ENOMEM); 1176 if (copy_from_user(buffer, user_buf, user_len) != 0) { 1177 kfree(buffer); 1178 return ERR_PTR(-EFAULT); 1179 } 1180 /* got the string, now strip linefeed. */ 1181 if (buffer[user_len - 1] == '\n') 1182 buffer[user_len - 1] = 0; 1183 else 1184 buffer[user_len] = 0; 1185 return buffer; 1186 } 1187 1188 static inline int 1189 debug_get_uint(char *buf) 1190 { 1191 int rc; 1192 1193 for(; isspace(*buf); buf++); 1194 rc = simple_strtoul(buf, &buf, 10); 1195 if(*buf){ 1196 printk("debug: no integer specified!\n"); 1197 rc = -EINVAL; 1198 } 1199 return rc; 1200 } 1201 1202 /* 1203 * functions for debug-views 1204 *********************************** 1205 */ 1206 1207 /* 1208 * prints out actual debug level 1209 */ 1210 1211 static int 1212 debug_prolog_pages_fn(debug_info_t * id, 1213 struct debug_view *view, char *out_buf) 1214 { 1215 return sprintf(out_buf, "%i\n", id->pages_per_area); 1216 } 1217 1218 /* 1219 * reads new size (number of pages per debug area) 1220 */ 1221 1222 static int 1223 debug_input_pages_fn(debug_info_t * id, struct debug_view *view, 1224 struct file *file, const char __user *user_buf, 1225 size_t user_len, loff_t * offset) 1226 { 1227 char *str; 1228 int rc,new_pages; 1229 1230 if (user_len > 0x10000) 1231 user_len = 0x10000; 1232 if (*offset != 0){ 1233 rc = -EPIPE; 1234 goto out; 1235 } 1236 str = debug_get_user_string(user_buf,user_len); 1237 if(IS_ERR(str)){ 1238 rc = PTR_ERR(str); 1239 goto out; 1240 } 1241 new_pages = debug_get_uint(str); 1242 if(new_pages < 0){ 1243 rc = -EINVAL; 1244 goto free_str; 1245 } 1246 rc = debug_set_size(id,id->nr_areas, new_pages); 1247 if(rc != 0){ 1248 rc = -EINVAL; 1249 goto free_str; 1250 } 1251 rc = user_len; 1252 free_str: 1253 kfree(str); 1254 out: 1255 *offset += user_len; 1256 return rc; /* number of input characters */ 1257 } 1258 1259 /* 1260 * prints out actual debug level 1261 */ 1262 1263 static int 1264 debug_prolog_level_fn(debug_info_t * id, struct debug_view *view, char *out_buf) 1265 { 1266 int rc = 0; 1267 1268 if(id->level == DEBUG_OFF_LEVEL) { 1269 rc = sprintf(out_buf,"-\n"); 1270 } 1271 else { 1272 rc = sprintf(out_buf, "%i\n", id->level); 1273 } 1274 return rc; 1275 } 1276 1277 /* 1278 * reads new debug level 1279 */ 1280 1281 static int 1282 debug_input_level_fn(debug_info_t * id, struct debug_view *view, 1283 struct file *file, const char __user *user_buf, 1284 size_t user_len, loff_t * offset) 1285 { 1286 char *str; 1287 int rc,new_level; 1288 1289 if (user_len > 0x10000) 1290 user_len = 0x10000; 1291 if (*offset != 0){ 1292 rc = -EPIPE; 1293 goto out; 1294 } 1295 str = debug_get_user_string(user_buf,user_len); 1296 if(IS_ERR(str)){ 1297 rc = PTR_ERR(str); 1298 goto out; 1299 } 1300 if(str[0] == '-'){ 1301 debug_set_level(id, DEBUG_OFF_LEVEL); 1302 rc = user_len; 1303 goto free_str; 1304 } else { 1305 new_level = debug_get_uint(str); 1306 } 1307 if(new_level < 0) { 1308 printk(KERN_INFO "debug: level `%s` is not valid\n", str); 1309 rc = -EINVAL; 1310 } else { 1311 debug_set_level(id, new_level); 1312 rc = user_len; 1313 } 1314 free_str: 1315 kfree(str); 1316 out: 1317 *offset += user_len; 1318 return rc; /* number of input characters */ 1319 } 1320 1321 1322 /* 1323 * flushes debug areas 1324 */ 1325 1326 static void debug_flush(debug_info_t* id, int area) 1327 { 1328 unsigned long flags; 1329 int i,j; 1330 1331 if(!id || !id->areas) 1332 return; 1333 spin_lock_irqsave(&id->lock,flags); 1334 if(area == DEBUG_FLUSH_ALL){ 1335 id->active_area = 0; 1336 memset(id->active_entries, 0, id->nr_areas * sizeof(int)); 1337 for (i = 0; i < id->nr_areas; i++) { 1338 id->active_pages[i] = 0; 1339 for(j = 0; j < id->pages_per_area; j++) { 1340 memset(id->areas[i][j], 0, PAGE_SIZE); 1341 } 1342 } 1343 printk(KERN_INFO "debug: %s: all areas flushed\n",id->name); 1344 } else if(area >= 0 && area < id->nr_areas) { 1345 id->active_entries[area] = 0; 1346 id->active_pages[area] = 0; 1347 for(i = 0; i < id->pages_per_area; i++) { 1348 memset(id->areas[area][i],0,PAGE_SIZE); 1349 } 1350 printk(KERN_INFO "debug: %s: area %i has been flushed\n", 1351 id->name, area); 1352 } else { 1353 printk(KERN_INFO 1354 "debug: %s: area %i cannot be flushed (range: %i - %i)\n", 1355 id->name, area, 0, id->nr_areas-1); 1356 } 1357 spin_unlock_irqrestore(&id->lock,flags); 1358 } 1359 1360 /* 1361 * view function: flushes debug areas 1362 */ 1363 1364 static int 1365 debug_input_flush_fn(debug_info_t * id, struct debug_view *view, 1366 struct file *file, const char __user *user_buf, 1367 size_t user_len, loff_t * offset) 1368 { 1369 char input_buf[1]; 1370 int rc = user_len; 1371 1372 if (user_len > 0x10000) 1373 user_len = 0x10000; 1374 if (*offset != 0){ 1375 rc = -EPIPE; 1376 goto out; 1377 } 1378 if (copy_from_user(input_buf, user_buf, 1)){ 1379 rc = -EFAULT; 1380 goto out; 1381 } 1382 if(input_buf[0] == '-') { 1383 debug_flush(id, DEBUG_FLUSH_ALL); 1384 goto out; 1385 } 1386 if (isdigit(input_buf[0])) { 1387 int area = ((int) input_buf[0] - (int) '0'); 1388 debug_flush(id, area); 1389 goto out; 1390 } 1391 1392 printk(KERN_INFO "debug: area `%c` is not valid\n", input_buf[0]); 1393 1394 out: 1395 *offset += user_len; 1396 return rc; /* number of input characters */ 1397 } 1398 1399 /* 1400 * prints debug header in raw format 1401 */ 1402 1403 static int 1404 debug_raw_header_fn(debug_info_t * id, struct debug_view *view, 1405 int area, debug_entry_t * entry, char *out_buf) 1406 { 1407 int rc; 1408 1409 rc = sizeof(debug_entry_t); 1410 memcpy(out_buf,entry,sizeof(debug_entry_t)); 1411 return rc; 1412 } 1413 1414 /* 1415 * prints debug data in raw format 1416 */ 1417 1418 static int 1419 debug_raw_format_fn(debug_info_t * id, struct debug_view *view, 1420 char *out_buf, const char *in_buf) 1421 { 1422 int rc; 1423 1424 rc = id->buf_size; 1425 memcpy(out_buf, in_buf, id->buf_size); 1426 return rc; 1427 } 1428 1429 /* 1430 * prints debug data in hex/ascii format 1431 */ 1432 1433 static int 1434 debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view, 1435 char *out_buf, const char *in_buf) 1436 { 1437 int i, rc = 0; 1438 1439 for (i = 0; i < id->buf_size; i++) { 1440 rc += sprintf(out_buf + rc, "%02x ", 1441 ((unsigned char *) in_buf)[i]); 1442 } 1443 rc += sprintf(out_buf + rc, "| "); 1444 for (i = 0; i < id->buf_size; i++) { 1445 unsigned char c = in_buf[i]; 1446 if (!isprint(c)) 1447 rc += sprintf(out_buf + rc, "."); 1448 else 1449 rc += sprintf(out_buf + rc, "%c", c); 1450 } 1451 rc += sprintf(out_buf + rc, "\n"); 1452 return rc; 1453 } 1454 1455 /* 1456 * prints header for debug entry 1457 */ 1458 1459 int 1460 debug_dflt_header_fn(debug_info_t * id, struct debug_view *view, 1461 int area, debug_entry_t * entry, char *out_buf) 1462 { 1463 struct timespec time_spec; 1464 unsigned long long time; 1465 char *except_str; 1466 unsigned long caller; 1467 int rc = 0; 1468 unsigned int level; 1469 1470 level = entry->id.fields.level; 1471 time = entry->id.stck; 1472 /* adjust todclock to 1970 */ 1473 time -= 0x8126d60e46000000LL - (0x3c26700LL * 1000000 * 4096); 1474 tod_to_timeval(time, &time_spec); 1475 1476 if (entry->id.fields.exception) 1477 except_str = "*"; 1478 else 1479 except_str = "-"; 1480 caller = ((unsigned long) entry->caller) & PSW_ADDR_INSN; 1481 rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %p ", 1482 area, time_spec.tv_sec, time_spec.tv_nsec / 1000, level, 1483 except_str, entry->id.fields.cpuid, (void *) caller); 1484 return rc; 1485 } 1486 1487 /* 1488 * prints debug data sprintf-formated: 1489 * debug_sprinf_event/exception calls must be used together with this view 1490 */ 1491 1492 #define DEBUG_SPRINTF_MAX_ARGS 10 1493 1494 static int 1495 debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view, 1496 char *out_buf, debug_sprintf_entry_t *curr_event) 1497 { 1498 int num_longs, num_used_args = 0,i, rc = 0; 1499 int index[DEBUG_SPRINTF_MAX_ARGS]; 1500 1501 /* count of longs fit into one entry */ 1502 num_longs = id->buf_size / sizeof(long); 1503 1504 if(num_longs < 1) 1505 goto out; /* bufsize of entry too small */ 1506 if(num_longs == 1) { 1507 /* no args, we use only the string */ 1508 strcpy(out_buf, curr_event->string); 1509 rc = strlen(curr_event->string); 1510 goto out; 1511 } 1512 1513 /* number of arguments used for sprintf (without the format string) */ 1514 num_used_args = min(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1)); 1515 1516 memset(index,0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int)); 1517 1518 for(i = 0; i < num_used_args; i++) 1519 index[i] = i; 1520 1521 rc = sprintf(out_buf, curr_event->string, curr_event->args[index[0]], 1522 curr_event->args[index[1]], curr_event->args[index[2]], 1523 curr_event->args[index[3]], curr_event->args[index[4]], 1524 curr_event->args[index[5]], curr_event->args[index[6]], 1525 curr_event->args[index[7]], curr_event->args[index[8]], 1526 curr_event->args[index[9]]); 1527 1528 out: 1529 1530 return rc; 1531 } 1532 1533 /* 1534 * clean up module 1535 */ 1536 static void __exit debug_exit(void) 1537 { 1538 debugfs_remove(debug_debugfs_root_entry); 1539 unregister_sysctl_table(s390dbf_sysctl_header); 1540 return; 1541 } 1542 1543 /* 1544 * module definitions 1545 */ 1546 postcore_initcall(debug_init); 1547 module_exit(debug_exit); 1548 MODULE_LICENSE("GPL"); 1549 1550 EXPORT_SYMBOL(debug_register); 1551 EXPORT_SYMBOL(debug_unregister); 1552 EXPORT_SYMBOL(debug_set_level); 1553 EXPORT_SYMBOL(debug_stop_all); 1554 EXPORT_SYMBOL(debug_register_view); 1555 EXPORT_SYMBOL(debug_unregister_view); 1556 EXPORT_SYMBOL(debug_event_common); 1557 EXPORT_SYMBOL(debug_exception_common); 1558 EXPORT_SYMBOL(debug_hex_ascii_view); 1559 EXPORT_SYMBOL(debug_raw_view); 1560 EXPORT_SYMBOL(debug_dflt_header_fn); 1561 EXPORT_SYMBOL(debug_sprintf_view); 1562 EXPORT_SYMBOL(debug_sprintf_exception); 1563 EXPORT_SYMBOL(debug_sprintf_event); 1564