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