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/config.h> 14 #include <linux/stddef.h> 15 #include <linux/kernel.h> 16 #include <linux/errno.h> 17 #include <linux/slab.h> 18 #include <linux/ctype.h> 19 #include <linux/sysctl.h> 20 #include <asm/uaccess.h> 21 #include <asm/semaphore.h> 22 #include <linux/module.h> 23 #include <linux/init.h> 24 #include <linux/fs.h> 25 #include <linux/debugfs.h> 26 27 #include <asm/debug.h> 28 29 #define DEBUG_PROLOG_ENTRY -1 30 31 #define ALL_AREAS 0 /* copy all debug areas */ 32 #define NO_AREAS 1 /* copy no debug areas */ 33 34 /* typedefs */ 35 36 typedef struct file_private_info { 37 loff_t offset; /* offset of last read in file */ 38 int act_area; /* number of last formated area */ 39 int act_page; /* act page in given area */ 40 int act_entry; /* last formated entry (offset */ 41 /* relative to beginning of last */ 42 /* formated page) */ 43 size_t act_entry_offset; /* up to this offset we copied */ 44 /* in last read the last formated */ 45 /* entry to userland */ 46 char temp_buf[2048]; /* buffer for output */ 47 debug_info_t *debug_info_org; /* original debug information */ 48 debug_info_t *debug_info_snap; /* snapshot of debug information */ 49 struct debug_view *view; /* used view of debug info */ 50 } file_private_info_t; 51 52 typedef struct 53 { 54 char *string; 55 /* 56 * This assumes that all args are converted into longs 57 * on L/390 this is the case for all types of parameter 58 * except of floats, and long long (32 bit) 59 * 60 */ 61 long args[0]; 62 } debug_sprintf_entry_t; 63 64 65 extern void tod_to_timeval(uint64_t todval, struct timespec *xtime); 66 67 /* internal function prototyes */ 68 69 static int debug_init(void); 70 static ssize_t debug_output(struct file *file, char __user *user_buf, 71 size_t user_len, loff_t * offset); 72 static ssize_t debug_input(struct file *file, const char __user *user_buf, 73 size_t user_len, loff_t * offset); 74 static int debug_open(struct inode *inode, struct file *file); 75 static int debug_close(struct inode *inode, struct file *file); 76 static debug_info_t* debug_info_create(char *name, int pages_per_area, 77 int nr_areas, int buf_size); 78 static void debug_info_get(debug_info_t *); 79 static void debug_info_put(debug_info_t *); 80 static int debug_prolog_level_fn(debug_info_t * id, 81 struct debug_view *view, char *out_buf); 82 static int debug_input_level_fn(debug_info_t * id, struct debug_view *view, 83 struct file *file, const char __user *user_buf, 84 size_t user_buf_size, loff_t * offset); 85 static int debug_prolog_pages_fn(debug_info_t * id, 86 struct debug_view *view, char *out_buf); 87 static int debug_input_pages_fn(debug_info_t * id, struct debug_view *view, 88 struct file *file, const char __user *user_buf, 89 size_t user_buf_size, loff_t * offset); 90 static int debug_input_flush_fn(debug_info_t * id, struct debug_view *view, 91 struct file *file, const char __user *user_buf, 92 size_t user_buf_size, loff_t * offset); 93 static int debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view, 94 char *out_buf, const char *in_buf); 95 static int debug_raw_format_fn(debug_info_t * id, 96 struct debug_view *view, char *out_buf, 97 const char *in_buf); 98 static int debug_raw_header_fn(debug_info_t * id, struct debug_view *view, 99 int area, debug_entry_t * entry, char *out_buf); 100 101 static int debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view, 102 char *out_buf, debug_sprintf_entry_t *curr_event); 103 104 /* globals */ 105 106 struct debug_view debug_raw_view = { 107 "raw", 108 NULL, 109 &debug_raw_header_fn, 110 &debug_raw_format_fn, 111 NULL, 112 NULL 113 }; 114 115 struct debug_view debug_hex_ascii_view = { 116 "hex_ascii", 117 NULL, 118 &debug_dflt_header_fn, 119 &debug_hex_ascii_format_fn, 120 NULL, 121 NULL 122 }; 123 124 struct debug_view debug_level_view = { 125 "level", 126 &debug_prolog_level_fn, 127 NULL, 128 NULL, 129 &debug_input_level_fn, 130 NULL 131 }; 132 133 struct debug_view debug_pages_view = { 134 "pages", 135 &debug_prolog_pages_fn, 136 NULL, 137 NULL, 138 &debug_input_pages_fn, 139 NULL 140 }; 141 142 struct debug_view debug_flush_view = { 143 "flush", 144 NULL, 145 NULL, 146 NULL, 147 &debug_input_flush_fn, 148 NULL 149 }; 150 151 struct debug_view debug_sprintf_view = { 152 "sprintf", 153 NULL, 154 &debug_dflt_header_fn, 155 (debug_format_proc_t*)&debug_sprintf_format_fn, 156 NULL, 157 NULL 158 }; 159 160 161 unsigned int debug_feature_version = __DEBUG_FEATURE_VERSION; 162 163 /* static globals */ 164 165 static debug_info_t *debug_area_first = NULL; 166 static debug_info_t *debug_area_last = NULL; 167 DECLARE_MUTEX(debug_lock); 168 169 static int initialized; 170 171 static struct file_operations debug_file_ops = { 172 .owner = THIS_MODULE, 173 .read = debug_output, 174 .write = debug_input, 175 .open = debug_open, 176 .release = debug_close, 177 }; 178 179 static struct dentry *debug_debugfs_root_entry; 180 181 /* functions */ 182 183 /* 184 * debug_areas_alloc 185 * - Debug areas are implemented as a threedimensonal array: 186 * areas[areanumber][pagenumber][pageoffset] 187 */ 188 189 static debug_entry_t*** 190 debug_areas_alloc(int pages_per_area, int nr_areas) 191 { 192 debug_entry_t*** areas; 193 int i,j; 194 195 areas = (debug_entry_t ***) kmalloc(nr_areas * 196 sizeof(debug_entry_t**), 197 GFP_KERNEL); 198 if (!areas) 199 goto fail_malloc_areas; 200 for (i = 0; i < nr_areas; i++) { 201 areas[i] = (debug_entry_t**) kmalloc(pages_per_area * 202 sizeof(debug_entry_t*),GFP_KERNEL); 203 if (!areas[i]) { 204 goto fail_malloc_areas2; 205 } 206 for(j = 0; j < pages_per_area; j++) { 207 areas[i][j] = kzalloc(PAGE_SIZE, GFP_KERNEL); 208 if(!areas[i][j]) { 209 for(j--; j >=0 ; j--) { 210 kfree(areas[i][j]); 211 } 212 kfree(areas[i]); 213 goto fail_malloc_areas2; 214 } 215 } 216 } 217 return areas; 218 219 fail_malloc_areas2: 220 for(i--; i >= 0; i--){ 221 for(j=0; j < pages_per_area;j++){ 222 kfree(areas[i][j]); 223 } 224 kfree(areas[i]); 225 } 226 kfree(areas); 227 fail_malloc_areas: 228 return NULL; 229 230 } 231 232 233 /* 234 * debug_info_alloc 235 * - alloc new debug-info 236 */ 237 238 static debug_info_t* 239 debug_info_alloc(char *name, int pages_per_area, int nr_areas, int buf_size, 240 int level, int mode) 241 { 242 debug_info_t* rc; 243 244 /* alloc everything */ 245 246 rc = (debug_info_t*) kmalloc(sizeof(debug_info_t), GFP_KERNEL); 247 if(!rc) 248 goto fail_malloc_rc; 249 rc->active_entries = kcalloc(nr_areas, sizeof(int), GFP_KERNEL); 250 if(!rc->active_entries) 251 goto fail_malloc_active_entries; 252 rc->active_pages = kcalloc(nr_areas, sizeof(int), GFP_KERNEL); 253 if(!rc->active_pages) 254 goto fail_malloc_active_pages; 255 if((mode == ALL_AREAS) && (pages_per_area != 0)){ 256 rc->areas = debug_areas_alloc(pages_per_area, nr_areas); 257 if(!rc->areas) 258 goto fail_malloc_areas; 259 } else { 260 rc->areas = NULL; 261 } 262 263 /* initialize members */ 264 265 spin_lock_init(&rc->lock); 266 rc->pages_per_area = pages_per_area; 267 rc->nr_areas = nr_areas; 268 rc->active_area = 0; 269 rc->level = level; 270 rc->buf_size = buf_size; 271 rc->entry_size = sizeof(debug_entry_t) + buf_size; 272 strlcpy(rc->name, name, sizeof(rc->name)-1); 273 memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *)); 274 memset(rc->debugfs_entries, 0 ,DEBUG_MAX_VIEWS * 275 sizeof(struct dentry*)); 276 atomic_set(&(rc->ref_count), 0); 277 278 return rc; 279 280 fail_malloc_areas: 281 kfree(rc->active_pages); 282 fail_malloc_active_pages: 283 kfree(rc->active_entries); 284 fail_malloc_active_entries: 285 kfree(rc); 286 fail_malloc_rc: 287 return NULL; 288 } 289 290 /* 291 * debug_areas_free 292 * - free all debug areas 293 */ 294 295 static void 296 debug_areas_free(debug_info_t* db_info) 297 { 298 int i,j; 299 300 if(!db_info->areas) 301 return; 302 for (i = 0; i < db_info->nr_areas; i++) { 303 for(j = 0; j < db_info->pages_per_area; j++) { 304 kfree(db_info->areas[i][j]); 305 } 306 kfree(db_info->areas[i]); 307 } 308 kfree(db_info->areas); 309 db_info->areas = NULL; 310 } 311 312 /* 313 * debug_info_free 314 * - free memory debug-info 315 */ 316 317 static void 318 debug_info_free(debug_info_t* db_info){ 319 debug_areas_free(db_info); 320 kfree(db_info->active_entries); 321 kfree(db_info->active_pages); 322 kfree(db_info); 323 } 324 325 /* 326 * debug_info_create 327 * - create new debug-info 328 */ 329 330 static debug_info_t* 331 debug_info_create(char *name, int pages_per_area, int nr_areas, int buf_size) 332 { 333 debug_info_t* rc; 334 335 rc = debug_info_alloc(name, pages_per_area, nr_areas, buf_size, 336 DEBUG_DEFAULT_LEVEL, ALL_AREAS); 337 if(!rc) 338 goto out; 339 340 /* create root directory */ 341 rc->debugfs_root_entry = debugfs_create_dir(rc->name, 342 debug_debugfs_root_entry); 343 344 /* append new element to linked list */ 345 if (!debug_area_first) { 346 /* first element in list */ 347 debug_area_first = rc; 348 rc->prev = NULL; 349 } else { 350 /* append element to end of list */ 351 debug_area_last->next = rc; 352 rc->prev = debug_area_last; 353 } 354 debug_area_last = rc; 355 rc->next = NULL; 356 357 debug_info_get(rc); 358 out: 359 return rc; 360 } 361 362 /* 363 * debug_info_copy 364 * - copy debug-info 365 */ 366 367 static debug_info_t* 368 debug_info_copy(debug_info_t* in, int mode) 369 { 370 int i,j; 371 debug_info_t* rc; 372 unsigned long flags; 373 374 /* get a consistent copy of the debug areas */ 375 do { 376 rc = debug_info_alloc(in->name, in->pages_per_area, 377 in->nr_areas, in->buf_size, in->level, mode); 378 spin_lock_irqsave(&in->lock, flags); 379 if(!rc) 380 goto out; 381 /* has something changed in the meantime ? */ 382 if((rc->pages_per_area == in->pages_per_area) && 383 (rc->nr_areas == in->nr_areas)) { 384 break; 385 } 386 spin_unlock_irqrestore(&in->lock, flags); 387 debug_info_free(rc); 388 } while (1); 389 390 if(!rc || (mode == NO_AREAS)) 391 goto out; 392 393 for(i = 0; i < in->nr_areas; i++){ 394 for(j = 0; j < in->pages_per_area; j++) { 395 memcpy(rc->areas[i][j], in->areas[i][j],PAGE_SIZE); 396 } 397 } 398 out: 399 spin_unlock_irqrestore(&in->lock, flags); 400 return rc; 401 } 402 403 /* 404 * debug_info_get 405 * - increments reference count for debug-info 406 */ 407 408 static void 409 debug_info_get(debug_info_t * db_info) 410 { 411 if (db_info) 412 atomic_inc(&db_info->ref_count); 413 } 414 415 /* 416 * debug_info_put: 417 * - decreases reference count for debug-info and frees it if necessary 418 */ 419 420 static void 421 debug_info_put(debug_info_t *db_info) 422 { 423 int i; 424 425 if (!db_info) 426 return; 427 if (atomic_dec_and_test(&db_info->ref_count)) { 428 for (i = 0; i < DEBUG_MAX_VIEWS; i++) { 429 if (!db_info->views[i]) 430 continue; 431 debugfs_remove(db_info->debugfs_entries[i]); 432 } 433 debugfs_remove(db_info->debugfs_root_entry); 434 if(db_info == debug_area_first) 435 debug_area_first = db_info->next; 436 if(db_info == debug_area_last) 437 debug_area_last = db_info->prev; 438 if(db_info->prev) db_info->prev->next = db_info->next; 439 if(db_info->next) db_info->next->prev = db_info->prev; 440 debug_info_free(db_info); 441 } 442 } 443 444 /* 445 * debug_format_entry: 446 * - format one debug entry and return size of formated data 447 */ 448 449 static int 450 debug_format_entry(file_private_info_t *p_info) 451 { 452 debug_info_t *id_snap = p_info->debug_info_snap; 453 struct debug_view *view = p_info->view; 454 debug_entry_t *act_entry; 455 size_t len = 0; 456 if(p_info->act_entry == DEBUG_PROLOG_ENTRY){ 457 /* print prolog */ 458 if (view->prolog_proc) 459 len += view->prolog_proc(id_snap,view,p_info->temp_buf); 460 goto out; 461 } 462 if (!id_snap->areas) /* this is true, if we have a prolog only view */ 463 goto out; /* or if 'pages_per_area' is 0 */ 464 act_entry = (debug_entry_t *) ((char*)id_snap->areas[p_info->act_area] 465 [p_info->act_page] + p_info->act_entry); 466 467 if (act_entry->id.stck == 0LL) 468 goto out; /* empty entry */ 469 if (view->header_proc) 470 len += view->header_proc(id_snap, view, p_info->act_area, 471 act_entry, p_info->temp_buf + len); 472 if (view->format_proc) 473 len += view->format_proc(id_snap, view, p_info->temp_buf + len, 474 DEBUG_DATA(act_entry)); 475 out: 476 return len; 477 } 478 479 /* 480 * debug_next_entry: 481 * - goto next entry in p_info 482 */ 483 484 static inline int 485 debug_next_entry(file_private_info_t *p_info) 486 { 487 debug_info_t *id; 488 489 id = p_info->debug_info_snap; 490 if(p_info->act_entry == DEBUG_PROLOG_ENTRY){ 491 p_info->act_entry = 0; 492 p_info->act_page = 0; 493 goto out; 494 } 495 if(!id->areas) 496 return 1; 497 p_info->act_entry += id->entry_size; 498 /* switch to next page, if we reached the end of the page */ 499 if (p_info->act_entry > (PAGE_SIZE - id->entry_size)){ 500 /* next page */ 501 p_info->act_entry = 0; 502 p_info->act_page += 1; 503 if((p_info->act_page % id->pages_per_area) == 0) { 504 /* next area */ 505 p_info->act_area++; 506 p_info->act_page=0; 507 } 508 if(p_info->act_area >= id->nr_areas) 509 return 1; 510 } 511 out: 512 return 0; 513 } 514 515 /* 516 * debug_output: 517 * - called for user read() 518 * - copies formated debug entries to the user buffer 519 */ 520 521 static ssize_t 522 debug_output(struct file *file, /* file descriptor */ 523 char __user *user_buf, /* user buffer */ 524 size_t len, /* length of buffer */ 525 loff_t *offset) /* offset in the file */ 526 { 527 size_t count = 0; 528 size_t entry_offset; 529 file_private_info_t *p_info; 530 531 p_info = ((file_private_info_t *) file->private_data); 532 if (*offset != p_info->offset) 533 return -EPIPE; 534 if(p_info->act_area >= p_info->debug_info_snap->nr_areas) 535 return 0; 536 entry_offset = p_info->act_entry_offset; 537 while(count < len){ 538 int formatted_line_size; 539 int formatted_line_residue; 540 int user_buf_residue; 541 size_t copy_size; 542 543 formatted_line_size = debug_format_entry(p_info); 544 formatted_line_residue = formatted_line_size - entry_offset; 545 user_buf_residue = len-count; 546 copy_size = min(user_buf_residue, formatted_line_residue); 547 if(copy_size){ 548 if (copy_to_user(user_buf + count, p_info->temp_buf 549 + entry_offset, copy_size)) 550 return -EFAULT; 551 count += copy_size; 552 entry_offset += copy_size; 553 } 554 if(copy_size == formatted_line_residue){ 555 entry_offset = 0; 556 if(debug_next_entry(p_info)) 557 goto out; 558 } 559 } 560 out: 561 p_info->offset = *offset + count; 562 p_info->act_entry_offset = entry_offset; 563 *offset = p_info->offset; 564 return count; 565 } 566 567 /* 568 * debug_input: 569 * - called for user write() 570 * - calls input function of view 571 */ 572 573 static ssize_t 574 debug_input(struct file *file, const char __user *user_buf, size_t length, 575 loff_t *offset) 576 { 577 int rc = 0; 578 file_private_info_t *p_info; 579 580 down(&debug_lock); 581 p_info = ((file_private_info_t *) file->private_data); 582 if (p_info->view->input_proc) 583 rc = p_info->view->input_proc(p_info->debug_info_org, 584 p_info->view, file, user_buf, 585 length, offset); 586 else 587 rc = -EPERM; 588 up(&debug_lock); 589 return rc; /* number of input characters */ 590 } 591 592 /* 593 * debug_open: 594 * - called for user open() 595 * - copies formated output to private_data area of the file 596 * handle 597 */ 598 599 static int 600 debug_open(struct inode *inode, struct file *file) 601 { 602 int i = 0, rc = 0; 603 file_private_info_t *p_info; 604 debug_info_t *debug_info, *debug_info_snapshot; 605 606 down(&debug_lock); 607 debug_info = (struct debug_info*)file->f_dentry->d_inode->u.generic_ip; 608 /* find debug view */ 609 for (i = 0; i < DEBUG_MAX_VIEWS; i++) { 610 if (!debug_info->views[i]) 611 continue; 612 else if (debug_info->debugfs_entries[i] == 613 file->f_dentry) { 614 goto found; /* found view ! */ 615 } 616 } 617 /* no entry found */ 618 rc = -EINVAL; 619 goto out; 620 621 found: 622 623 /* Make snapshot of current debug areas to get it consistent. */ 624 /* To copy all the areas is only needed, if we have a view which */ 625 /* formats the debug areas. */ 626 627 if(!debug_info->views[i]->format_proc && 628 !debug_info->views[i]->header_proc){ 629 debug_info_snapshot = debug_info_copy(debug_info, NO_AREAS); 630 } else { 631 debug_info_snapshot = debug_info_copy(debug_info, ALL_AREAS); 632 } 633 634 if(!debug_info_snapshot){ 635 rc = -ENOMEM; 636 goto out; 637 } 638 p_info = (file_private_info_t *) kmalloc(sizeof(file_private_info_t), 639 GFP_KERNEL); 640 if(!p_info){ 641 if(debug_info_snapshot) 642 debug_info_free(debug_info_snapshot); 643 rc = -ENOMEM; 644 goto out; 645 } 646 p_info->offset = 0; 647 p_info->debug_info_snap = debug_info_snapshot; 648 p_info->debug_info_org = debug_info; 649 p_info->view = debug_info->views[i]; 650 p_info->act_area = 0; 651 p_info->act_page = 0; 652 p_info->act_entry = DEBUG_PROLOG_ENTRY; 653 p_info->act_entry_offset = 0; 654 file->private_data = p_info; 655 debug_info_get(debug_info); 656 out: 657 up(&debug_lock); 658 return rc; 659 } 660 661 /* 662 * debug_close: 663 * - called for user close() 664 * - deletes private_data area of the file handle 665 */ 666 667 static int 668 debug_close(struct inode *inode, struct file *file) 669 { 670 file_private_info_t *p_info; 671 p_info = (file_private_info_t *) file->private_data; 672 if(p_info->debug_info_snap) 673 debug_info_free(p_info->debug_info_snap); 674 debug_info_put(p_info->debug_info_org); 675 kfree(file->private_data); 676 return 0; /* success */ 677 } 678 679 /* 680 * debug_register: 681 * - creates and initializes debug area for the caller 682 * - returns handle for debug area 683 */ 684 685 debug_info_t* 686 debug_register (char *name, int pages_per_area, int nr_areas, int buf_size) 687 { 688 debug_info_t *rc = NULL; 689 690 if (!initialized) 691 BUG(); 692 down(&debug_lock); 693 694 /* create new debug_info */ 695 696 rc = debug_info_create(name, pages_per_area, nr_areas, buf_size); 697 if(!rc) 698 goto out; 699 debug_register_view(rc, &debug_level_view); 700 debug_register_view(rc, &debug_flush_view); 701 debug_register_view(rc, &debug_pages_view); 702 out: 703 if (!rc){ 704 printk(KERN_ERR "debug: debug_register failed for %s\n",name); 705 } 706 up(&debug_lock); 707 return rc; 708 } 709 710 /* 711 * debug_unregister: 712 * - give back debug area 713 */ 714 715 void 716 debug_unregister(debug_info_t * id) 717 { 718 if (!id) 719 goto out; 720 down(&debug_lock); 721 debug_info_put(id); 722 up(&debug_lock); 723 724 out: 725 return; 726 } 727 728 /* 729 * debug_set_size: 730 * - set area size (number of pages) and number of areas 731 */ 732 static int 733 debug_set_size(debug_info_t* id, int nr_areas, int pages_per_area) 734 { 735 unsigned long flags; 736 debug_entry_t *** new_areas; 737 int rc=0; 738 739 if(!id || (nr_areas <= 0) || (pages_per_area < 0)) 740 return -EINVAL; 741 if(pages_per_area > 0){ 742 new_areas = debug_areas_alloc(pages_per_area, nr_areas); 743 if(!new_areas) { 744 printk(KERN_WARNING "debug: could not allocate memory "\ 745 "for pagenumber: %i\n",pages_per_area); 746 rc = -ENOMEM; 747 goto out; 748 } 749 } else { 750 new_areas = NULL; 751 } 752 spin_lock_irqsave(&id->lock,flags); 753 debug_areas_free(id); 754 id->areas = new_areas; 755 id->nr_areas = nr_areas; 756 id->pages_per_area = pages_per_area; 757 id->active_area = 0; 758 memset(id->active_entries,0,sizeof(int)*id->nr_areas); 759 memset(id->active_pages, 0, sizeof(int)*id->nr_areas); 760 spin_unlock_irqrestore(&id->lock,flags); 761 printk(KERN_INFO "debug: %s: set new size (%i pages)\n"\ 762 ,id->name, pages_per_area); 763 out: 764 return rc; 765 } 766 767 /* 768 * debug_set_level: 769 * - set actual debug level 770 */ 771 772 void 773 debug_set_level(debug_info_t* id, int new_level) 774 { 775 unsigned long flags; 776 if(!id) 777 return; 778 spin_lock_irqsave(&id->lock,flags); 779 if(new_level == DEBUG_OFF_LEVEL){ 780 id->level = DEBUG_OFF_LEVEL; 781 printk(KERN_INFO "debug: %s: switched off\n",id->name); 782 } else if ((new_level > DEBUG_MAX_LEVEL) || (new_level < 0)) { 783 printk(KERN_INFO 784 "debug: %s: level %i is out of range (%i - %i)\n", 785 id->name, new_level, 0, DEBUG_MAX_LEVEL); 786 } else { 787 id->level = new_level; 788 } 789 spin_unlock_irqrestore(&id->lock,flags); 790 } 791 792 793 /* 794 * proceed_active_entry: 795 * - set active entry to next in the ring buffer 796 */ 797 798 static inline void 799 proceed_active_entry(debug_info_t * id) 800 { 801 if ((id->active_entries[id->active_area] += id->entry_size) 802 > (PAGE_SIZE - id->entry_size)){ 803 id->active_entries[id->active_area] = 0; 804 id->active_pages[id->active_area] = 805 (id->active_pages[id->active_area] + 1) % 806 id->pages_per_area; 807 } 808 } 809 810 /* 811 * proceed_active_area: 812 * - set active area to next in the ring buffer 813 */ 814 815 static inline void 816 proceed_active_area(debug_info_t * id) 817 { 818 id->active_area++; 819 id->active_area = id->active_area % id->nr_areas; 820 } 821 822 /* 823 * get_active_entry: 824 */ 825 826 static inline debug_entry_t* 827 get_active_entry(debug_info_t * id) 828 { 829 return (debug_entry_t *) (((char *) id->areas[id->active_area] 830 [id->active_pages[id->active_area]]) + 831 id->active_entries[id->active_area]); 832 } 833 834 /* 835 * debug_finish_entry: 836 * - set timestamp, caller address, cpu number etc. 837 */ 838 839 static inline void 840 debug_finish_entry(debug_info_t * id, debug_entry_t* active, int level, 841 int exception) 842 { 843 active->id.stck = get_clock(); 844 active->id.fields.cpuid = smp_processor_id(); 845 active->caller = __builtin_return_address(0); 846 active->id.fields.exception = exception; 847 active->id.fields.level = level; 848 proceed_active_entry(id); 849 if(exception) 850 proceed_active_area(id); 851 } 852 853 static int debug_stoppable=1; 854 static int debug_active=1; 855 856 #define CTL_S390DBF 5677 857 #define CTL_S390DBF_STOPPABLE 5678 858 #define CTL_S390DBF_ACTIVE 5679 859 860 /* 861 * proc handler for the running debug_active sysctl 862 * always allow read, allow write only if debug_stoppable is set or 863 * if debug_active is already off 864 */ 865 static int 866 s390dbf_procactive(ctl_table *table, int write, struct file *filp, 867 void __user *buffer, size_t *lenp, loff_t *ppos) 868 { 869 if (!write || debug_stoppable || !debug_active) 870 return proc_dointvec(table, write, filp, buffer, lenp, ppos); 871 else 872 return 0; 873 } 874 875 876 static struct ctl_table s390dbf_table[] = { 877 { 878 .ctl_name = CTL_S390DBF_STOPPABLE, 879 .procname = "debug_stoppable", 880 .data = &debug_stoppable, 881 .maxlen = sizeof(int), 882 .mode = S_IRUGO | S_IWUSR, 883 .proc_handler = &proc_dointvec, 884 .strategy = &sysctl_intvec, 885 }, 886 { 887 .ctl_name = CTL_S390DBF_ACTIVE, 888 .procname = "debug_active", 889 .data = &debug_active, 890 .maxlen = sizeof(int), 891 .mode = S_IRUGO | S_IWUSR, 892 .proc_handler = &s390dbf_procactive, 893 .strategy = &sysctl_intvec, 894 }, 895 { .ctl_name = 0 } 896 }; 897 898 static struct ctl_table s390dbf_dir_table[] = { 899 { 900 .ctl_name = CTL_S390DBF, 901 .procname = "s390dbf", 902 .maxlen = 0, 903 .mode = S_IRUGO | S_IXUGO, 904 .child = s390dbf_table, 905 }, 906 { .ctl_name = 0 } 907 }; 908 909 struct ctl_table_header *s390dbf_sysctl_header; 910 911 void 912 debug_stop_all(void) 913 { 914 if (debug_stoppable) 915 debug_active = 0; 916 } 917 918 919 /* 920 * debug_event_common: 921 * - write debug entry with given size 922 */ 923 924 debug_entry_t* 925 debug_event_common(debug_info_t * id, int level, const void *buf, int len) 926 { 927 unsigned long flags; 928 debug_entry_t *active; 929 930 if (!debug_active || !id->areas) 931 return NULL; 932 spin_lock_irqsave(&id->lock, flags); 933 active = get_active_entry(id); 934 memset(DEBUG_DATA(active), 0, id->buf_size); 935 memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size)); 936 debug_finish_entry(id, active, level, 0); 937 spin_unlock_irqrestore(&id->lock, flags); 938 939 return active; 940 } 941 942 /* 943 * debug_exception_common: 944 * - write debug entry with given size and switch to next debug area 945 */ 946 947 debug_entry_t 948 *debug_exception_common(debug_info_t * id, int level, const void *buf, int len) 949 { 950 unsigned long flags; 951 debug_entry_t *active; 952 953 if (!debug_active || !id->areas) 954 return NULL; 955 spin_lock_irqsave(&id->lock, flags); 956 active = get_active_entry(id); 957 memset(DEBUG_DATA(active), 0, id->buf_size); 958 memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size)); 959 debug_finish_entry(id, active, level, 1); 960 spin_unlock_irqrestore(&id->lock, flags); 961 962 return active; 963 } 964 965 /* 966 * counts arguments in format string for sprintf view 967 */ 968 969 static inline int 970 debug_count_numargs(char *string) 971 { 972 int numargs=0; 973 974 while(*string) { 975 if(*string++=='%') 976 numargs++; 977 } 978 return(numargs); 979 } 980 981 /* 982 * debug_sprintf_event: 983 */ 984 985 debug_entry_t* 986 debug_sprintf_event(debug_info_t* id, int level,char *string,...) 987 { 988 va_list ap; 989 int numargs,idx; 990 unsigned long flags; 991 debug_sprintf_entry_t *curr_event; 992 debug_entry_t *active; 993 994 if((!id) || (level > id->level)) 995 return NULL; 996 if (!debug_active || !id->areas) 997 return NULL; 998 numargs=debug_count_numargs(string); 999 1000 spin_lock_irqsave(&id->lock, flags); 1001 active = get_active_entry(id); 1002 curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active); 1003 va_start(ap,string); 1004 curr_event->string=string; 1005 for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++) 1006 curr_event->args[idx]=va_arg(ap,long); 1007 va_end(ap); 1008 debug_finish_entry(id, active, level, 0); 1009 spin_unlock_irqrestore(&id->lock, flags); 1010 1011 return active; 1012 } 1013 1014 /* 1015 * debug_sprintf_exception: 1016 */ 1017 1018 debug_entry_t* 1019 debug_sprintf_exception(debug_info_t* id, int level,char *string,...) 1020 { 1021 va_list ap; 1022 int numargs,idx; 1023 unsigned long flags; 1024 debug_sprintf_entry_t *curr_event; 1025 debug_entry_t *active; 1026 1027 if((!id) || (level > id->level)) 1028 return NULL; 1029 if (!debug_active || !id->areas) 1030 return NULL; 1031 1032 numargs=debug_count_numargs(string); 1033 1034 spin_lock_irqsave(&id->lock, flags); 1035 active = get_active_entry(id); 1036 curr_event=(debug_sprintf_entry_t *)DEBUG_DATA(active); 1037 va_start(ap,string); 1038 curr_event->string=string; 1039 for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++) 1040 curr_event->args[idx]=va_arg(ap,long); 1041 va_end(ap); 1042 debug_finish_entry(id, active, level, 1); 1043 spin_unlock_irqrestore(&id->lock, flags); 1044 1045 return active; 1046 } 1047 1048 /* 1049 * debug_init: 1050 * - is called exactly once to initialize the debug feature 1051 */ 1052 1053 static int 1054 __init debug_init(void) 1055 { 1056 int rc = 0; 1057 1058 s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table, 1); 1059 down(&debug_lock); 1060 debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT,NULL); 1061 printk(KERN_INFO "debug: Initialization complete\n"); 1062 initialized = 1; 1063 up(&debug_lock); 1064 1065 return rc; 1066 } 1067 1068 /* 1069 * debug_register_view: 1070 */ 1071 1072 int 1073 debug_register_view(debug_info_t * id, struct debug_view *view) 1074 { 1075 int rc = 0; 1076 int i; 1077 unsigned long flags; 1078 mode_t mode = S_IFREG; 1079 struct dentry *pde; 1080 1081 if (!id) 1082 goto out; 1083 if (view->prolog_proc || view->format_proc || view->header_proc) 1084 mode |= S_IRUSR; 1085 if (view->input_proc) 1086 mode |= S_IWUSR; 1087 pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry, 1088 id , &debug_file_ops); 1089 if (!pde){ 1090 printk(KERN_WARNING "debug: debugfs_create_file() failed!"\ 1091 " Cannot register view %s/%s\n", id->name,view->name); 1092 rc = -1; 1093 goto out; 1094 } 1095 spin_lock_irqsave(&id->lock, flags); 1096 for (i = 0; i < DEBUG_MAX_VIEWS; i++) { 1097 if (!id->views[i]) 1098 break; 1099 } 1100 if (i == DEBUG_MAX_VIEWS) { 1101 printk(KERN_WARNING "debug: cannot register view %s/%s\n", 1102 id->name,view->name); 1103 printk(KERN_WARNING 1104 "debug: maximum number of views reached (%i)!\n", i); 1105 debugfs_remove(pde); 1106 rc = -1; 1107 } else { 1108 id->views[i] = view; 1109 id->debugfs_entries[i] = pde; 1110 } 1111 spin_unlock_irqrestore(&id->lock, flags); 1112 out: 1113 return rc; 1114 } 1115 1116 /* 1117 * debug_unregister_view: 1118 */ 1119 1120 int 1121 debug_unregister_view(debug_info_t * id, struct debug_view *view) 1122 { 1123 int rc = 0; 1124 int i; 1125 unsigned long flags; 1126 1127 if (!id) 1128 goto out; 1129 spin_lock_irqsave(&id->lock, flags); 1130 for (i = 0; i < DEBUG_MAX_VIEWS; i++) { 1131 if (id->views[i] == view) 1132 break; 1133 } 1134 if (i == DEBUG_MAX_VIEWS) 1135 rc = -1; 1136 else { 1137 debugfs_remove(id->debugfs_entries[i]); 1138 id->views[i] = NULL; 1139 rc = 0; 1140 } 1141 spin_unlock_irqrestore(&id->lock, flags); 1142 out: 1143 return rc; 1144 } 1145 1146 static inline char * 1147 debug_get_user_string(const char __user *user_buf, size_t user_len) 1148 { 1149 char* buffer; 1150 1151 buffer = kmalloc(user_len + 1, GFP_KERNEL); 1152 if (!buffer) 1153 return ERR_PTR(-ENOMEM); 1154 if (copy_from_user(buffer, user_buf, user_len) != 0) { 1155 kfree(buffer); 1156 return ERR_PTR(-EFAULT); 1157 } 1158 /* got the string, now strip linefeed. */ 1159 if (buffer[user_len - 1] == '\n') 1160 buffer[user_len - 1] = 0; 1161 else 1162 buffer[user_len] = 0; 1163 return buffer; 1164 } 1165 1166 static inline int 1167 debug_get_uint(char *buf) 1168 { 1169 int rc; 1170 1171 for(; isspace(*buf); buf++); 1172 rc = simple_strtoul(buf, &buf, 10); 1173 if(*buf){ 1174 printk("debug: no integer specified!\n"); 1175 rc = -EINVAL; 1176 } 1177 return rc; 1178 } 1179 1180 /* 1181 * functions for debug-views 1182 *********************************** 1183 */ 1184 1185 /* 1186 * prints out actual debug level 1187 */ 1188 1189 static int 1190 debug_prolog_pages_fn(debug_info_t * id, 1191 struct debug_view *view, char *out_buf) 1192 { 1193 return sprintf(out_buf, "%i\n", id->pages_per_area); 1194 } 1195 1196 /* 1197 * reads new size (number of pages per debug area) 1198 */ 1199 1200 static int 1201 debug_input_pages_fn(debug_info_t * id, struct debug_view *view, 1202 struct file *file, const char __user *user_buf, 1203 size_t user_len, loff_t * offset) 1204 { 1205 char *str; 1206 int rc,new_pages; 1207 1208 if (user_len > 0x10000) 1209 user_len = 0x10000; 1210 if (*offset != 0){ 1211 rc = -EPIPE; 1212 goto out; 1213 } 1214 str = debug_get_user_string(user_buf,user_len); 1215 if(IS_ERR(str)){ 1216 rc = PTR_ERR(str); 1217 goto out; 1218 } 1219 new_pages = debug_get_uint(str); 1220 if(new_pages < 0){ 1221 rc = -EINVAL; 1222 goto free_str; 1223 } 1224 rc = debug_set_size(id,id->nr_areas, new_pages); 1225 if(rc != 0){ 1226 rc = -EINVAL; 1227 goto free_str; 1228 } 1229 rc = user_len; 1230 free_str: 1231 kfree(str); 1232 out: 1233 *offset += user_len; 1234 return rc; /* number of input characters */ 1235 } 1236 1237 /* 1238 * prints out actual debug level 1239 */ 1240 1241 static int 1242 debug_prolog_level_fn(debug_info_t * id, struct debug_view *view, char *out_buf) 1243 { 1244 int rc = 0; 1245 1246 if(id->level == DEBUG_OFF_LEVEL) { 1247 rc = sprintf(out_buf,"-\n"); 1248 } 1249 else { 1250 rc = sprintf(out_buf, "%i\n", id->level); 1251 } 1252 return rc; 1253 } 1254 1255 /* 1256 * reads new debug level 1257 */ 1258 1259 static int 1260 debug_input_level_fn(debug_info_t * id, struct debug_view *view, 1261 struct file *file, const char __user *user_buf, 1262 size_t user_len, loff_t * offset) 1263 { 1264 char *str; 1265 int rc,new_level; 1266 1267 if (user_len > 0x10000) 1268 user_len = 0x10000; 1269 if (*offset != 0){ 1270 rc = -EPIPE; 1271 goto out; 1272 } 1273 str = debug_get_user_string(user_buf,user_len); 1274 if(IS_ERR(str)){ 1275 rc = PTR_ERR(str); 1276 goto out; 1277 } 1278 if(str[0] == '-'){ 1279 debug_set_level(id, DEBUG_OFF_LEVEL); 1280 rc = user_len; 1281 goto free_str; 1282 } else { 1283 new_level = debug_get_uint(str); 1284 } 1285 if(new_level < 0) { 1286 printk(KERN_INFO "debug: level `%s` is not valid\n", str); 1287 rc = -EINVAL; 1288 } else { 1289 debug_set_level(id, new_level); 1290 rc = user_len; 1291 } 1292 free_str: 1293 kfree(str); 1294 out: 1295 *offset += user_len; 1296 return rc; /* number of input characters */ 1297 } 1298 1299 1300 /* 1301 * flushes debug areas 1302 */ 1303 1304 void 1305 debug_flush(debug_info_t* id, int area) 1306 { 1307 unsigned long flags; 1308 int i,j; 1309 1310 if(!id || !id->areas) 1311 return; 1312 spin_lock_irqsave(&id->lock,flags); 1313 if(area == DEBUG_FLUSH_ALL){ 1314 id->active_area = 0; 1315 memset(id->active_entries, 0, id->nr_areas * sizeof(int)); 1316 for (i = 0; i < id->nr_areas; i++) { 1317 id->active_pages[i] = 0; 1318 for(j = 0; j < id->pages_per_area; j++) { 1319 memset(id->areas[i][j], 0, PAGE_SIZE); 1320 } 1321 } 1322 printk(KERN_INFO "debug: %s: all areas flushed\n",id->name); 1323 } else if(area >= 0 && area < id->nr_areas) { 1324 id->active_entries[area] = 0; 1325 id->active_pages[area] = 0; 1326 for(i = 0; i < id->pages_per_area; i++) { 1327 memset(id->areas[area][i],0,PAGE_SIZE); 1328 } 1329 printk(KERN_INFO "debug: %s: area %i has been flushed\n", 1330 id->name, area); 1331 } else { 1332 printk(KERN_INFO 1333 "debug: %s: area %i cannot be flushed (range: %i - %i)\n", 1334 id->name, area, 0, id->nr_areas-1); 1335 } 1336 spin_unlock_irqrestore(&id->lock,flags); 1337 } 1338 1339 /* 1340 * view function: flushes debug areas 1341 */ 1342 1343 static int 1344 debug_input_flush_fn(debug_info_t * id, struct debug_view *view, 1345 struct file *file, const char __user *user_buf, 1346 size_t user_len, loff_t * offset) 1347 { 1348 char input_buf[1]; 1349 int rc = user_len; 1350 1351 if (user_len > 0x10000) 1352 user_len = 0x10000; 1353 if (*offset != 0){ 1354 rc = -EPIPE; 1355 goto out; 1356 } 1357 if (copy_from_user(input_buf, user_buf, 1)){ 1358 rc = -EFAULT; 1359 goto out; 1360 } 1361 if(input_buf[0] == '-') { 1362 debug_flush(id, DEBUG_FLUSH_ALL); 1363 goto out; 1364 } 1365 if (isdigit(input_buf[0])) { 1366 int area = ((int) input_buf[0] - (int) '0'); 1367 debug_flush(id, area); 1368 goto out; 1369 } 1370 1371 printk(KERN_INFO "debug: area `%c` is not valid\n", input_buf[0]); 1372 1373 out: 1374 *offset += user_len; 1375 return rc; /* number of input characters */ 1376 } 1377 1378 /* 1379 * prints debug header in raw format 1380 */ 1381 1382 static int 1383 debug_raw_header_fn(debug_info_t * id, struct debug_view *view, 1384 int area, debug_entry_t * entry, char *out_buf) 1385 { 1386 int rc; 1387 1388 rc = sizeof(debug_entry_t); 1389 memcpy(out_buf,entry,sizeof(debug_entry_t)); 1390 return rc; 1391 } 1392 1393 /* 1394 * prints debug data in raw format 1395 */ 1396 1397 static int 1398 debug_raw_format_fn(debug_info_t * id, struct debug_view *view, 1399 char *out_buf, const char *in_buf) 1400 { 1401 int rc; 1402 1403 rc = id->buf_size; 1404 memcpy(out_buf, in_buf, id->buf_size); 1405 return rc; 1406 } 1407 1408 /* 1409 * prints debug data in hex/ascii format 1410 */ 1411 1412 static int 1413 debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view, 1414 char *out_buf, const char *in_buf) 1415 { 1416 int i, rc = 0; 1417 1418 for (i = 0; i < id->buf_size; i++) { 1419 rc += sprintf(out_buf + rc, "%02x ", 1420 ((unsigned char *) in_buf)[i]); 1421 } 1422 rc += sprintf(out_buf + rc, "| "); 1423 for (i = 0; i < id->buf_size; i++) { 1424 unsigned char c = in_buf[i]; 1425 if (!isprint(c)) 1426 rc += sprintf(out_buf + rc, "."); 1427 else 1428 rc += sprintf(out_buf + rc, "%c", c); 1429 } 1430 rc += sprintf(out_buf + rc, "\n"); 1431 return rc; 1432 } 1433 1434 /* 1435 * prints header for debug entry 1436 */ 1437 1438 int 1439 debug_dflt_header_fn(debug_info_t * id, struct debug_view *view, 1440 int area, debug_entry_t * entry, char *out_buf) 1441 { 1442 struct timespec time_spec; 1443 unsigned long long time; 1444 char *except_str; 1445 unsigned long caller; 1446 int rc = 0; 1447 unsigned int level; 1448 1449 level = entry->id.fields.level; 1450 time = entry->id.stck; 1451 /* adjust todclock to 1970 */ 1452 time -= 0x8126d60e46000000LL - (0x3c26700LL * 1000000 * 4096); 1453 tod_to_timeval(time, &time_spec); 1454 1455 if (entry->id.fields.exception) 1456 except_str = "*"; 1457 else 1458 except_str = "-"; 1459 caller = ((unsigned long) entry->caller) & PSW_ADDR_INSN; 1460 rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %p ", 1461 area, time_spec.tv_sec, time_spec.tv_nsec / 1000, level, 1462 except_str, entry->id.fields.cpuid, (void *) caller); 1463 return rc; 1464 } 1465 1466 /* 1467 * prints debug data sprintf-formated: 1468 * debug_sprinf_event/exception calls must be used together with this view 1469 */ 1470 1471 #define DEBUG_SPRINTF_MAX_ARGS 10 1472 1473 static int 1474 debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view, 1475 char *out_buf, debug_sprintf_entry_t *curr_event) 1476 { 1477 int num_longs, num_used_args = 0,i, rc = 0; 1478 int index[DEBUG_SPRINTF_MAX_ARGS]; 1479 1480 /* count of longs fit into one entry */ 1481 num_longs = id->buf_size / sizeof(long); 1482 1483 if(num_longs < 1) 1484 goto out; /* bufsize of entry too small */ 1485 if(num_longs == 1) { 1486 /* no args, we use only the string */ 1487 strcpy(out_buf, curr_event->string); 1488 rc = strlen(curr_event->string); 1489 goto out; 1490 } 1491 1492 /* number of arguments used for sprintf (without the format string) */ 1493 num_used_args = min(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1)); 1494 1495 memset(index,0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int)); 1496 1497 for(i = 0; i < num_used_args; i++) 1498 index[i] = i; 1499 1500 rc = sprintf(out_buf, curr_event->string, curr_event->args[index[0]], 1501 curr_event->args[index[1]], curr_event->args[index[2]], 1502 curr_event->args[index[3]], curr_event->args[index[4]], 1503 curr_event->args[index[5]], curr_event->args[index[6]], 1504 curr_event->args[index[7]], curr_event->args[index[8]], 1505 curr_event->args[index[9]]); 1506 1507 out: 1508 1509 return rc; 1510 } 1511 1512 /* 1513 * clean up module 1514 */ 1515 void 1516 __exit debug_exit(void) 1517 { 1518 debugfs_remove(debug_debugfs_root_entry); 1519 unregister_sysctl_table(s390dbf_sysctl_header); 1520 return; 1521 } 1522 1523 /* 1524 * module definitions 1525 */ 1526 postcore_initcall(debug_init); 1527 module_exit(debug_exit); 1528 MODULE_LICENSE("GPL"); 1529 1530 EXPORT_SYMBOL(debug_register); 1531 EXPORT_SYMBOL(debug_unregister); 1532 EXPORT_SYMBOL(debug_set_level); 1533 EXPORT_SYMBOL(debug_stop_all); 1534 EXPORT_SYMBOL(debug_register_view); 1535 EXPORT_SYMBOL(debug_unregister_view); 1536 EXPORT_SYMBOL(debug_event_common); 1537 EXPORT_SYMBOL(debug_exception_common); 1538 EXPORT_SYMBOL(debug_hex_ascii_view); 1539 EXPORT_SYMBOL(debug_raw_view); 1540 EXPORT_SYMBOL(debug_dflt_header_fn); 1541 EXPORT_SYMBOL(debug_sprintf_view); 1542 EXPORT_SYMBOL(debug_sprintf_exception); 1543 EXPORT_SYMBOL(debug_sprintf_event); 1544