1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * S/390 debug facility 4 * 5 * Copyright IBM Corp. 1999, 2012 6 * 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 #define KMSG_COMPONENT "s390dbf" 14 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 15 16 #include <linux/stddef.h> 17 #include <linux/kernel.h> 18 #include <linux/errno.h> 19 #include <linux/slab.h> 20 #include <linux/ctype.h> 21 #include <linux/string.h> 22 #include <linux/sysctl.h> 23 #include <linux/uaccess.h> 24 #include <linux/export.h> 25 #include <linux/init.h> 26 #include <linux/fs.h> 27 #include <linux/debugfs.h> 28 29 #include <asm/debug.h> 30 31 #define DEBUG_PROLOG_ENTRY -1 32 33 #define ALL_AREAS 0 /* copy all debug areas */ 34 #define NO_AREAS 1 /* copy no debug areas */ 35 36 /* typedefs */ 37 38 typedef struct file_private_info { 39 loff_t offset; /* offset of last read in file */ 40 int act_area; /* number of last formated area */ 41 int act_page; /* act page in given area */ 42 int act_entry; /* last formated entry (offset */ 43 /* relative to beginning of last */ 44 /* formated page) */ 45 size_t act_entry_offset; /* up to this offset we copied */ 46 /* in last read the last formated */ 47 /* entry to userland */ 48 char temp_buf[2048]; /* buffer for output */ 49 debug_info_t *debug_info_org; /* original debug information */ 50 debug_info_t *debug_info_snap; /* snapshot of debug information */ 51 struct debug_view *view; /* used view of debug info */ 52 } file_private_info_t; 53 54 typedef struct { 55 char *string; 56 /* 57 * This assumes that all args are converted into longs 58 * on L/390 this is the case for all types of parameter 59 * except of floats, and long long (32 bit) 60 * 61 */ 62 long args[0]; 63 } debug_sprintf_entry_t; 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(const char *name, int pages_per_area, 75 int nr_areas, int buf_size, umode_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 EXPORT_SYMBOL(debug_raw_view); 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 EXPORT_SYMBOL(debug_hex_ascii_view); 123 124 static 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 static 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 static 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 EXPORT_SYMBOL(debug_sprintf_view); 160 161 /* used by dump analysis tools to determine version of debug feature */ 162 static unsigned int __used debug_feature_version = __DEBUG_FEATURE_VERSION; 163 164 /* static globals */ 165 166 static debug_info_t *debug_area_first; 167 static debug_info_t *debug_area_last; 168 static DEFINE_MUTEX(debug_mutex); 169 170 static int initialized; 171 static int debug_critical; 172 173 static const struct file_operations debug_file_ops = { 174 .owner = THIS_MODULE, 175 .read = debug_output, 176 .write = debug_input, 177 .open = debug_open, 178 .release = debug_close, 179 .llseek = no_llseek, 180 }; 181 182 static struct dentry *debug_debugfs_root_entry; 183 184 /* functions */ 185 186 /* 187 * debug_areas_alloc 188 * - Debug areas are implemented as a threedimensonal array: 189 * areas[areanumber][pagenumber][pageoffset] 190 */ 191 192 static debug_entry_t ***debug_areas_alloc(int pages_per_area, int nr_areas) 193 { 194 debug_entry_t ***areas; 195 int i, j; 196 197 areas = kmalloc_array(nr_areas, sizeof(debug_entry_t **), GFP_KERNEL); 198 if (!areas) 199 goto fail_malloc_areas; 200 for (i = 0; i < nr_areas; i++) { 201 areas[i] = kmalloc_array(pages_per_area, 202 sizeof(debug_entry_t *), 203 GFP_KERNEL); 204 if (!areas[i]) 205 goto fail_malloc_areas2; 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 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 kfree(areas[i]); 223 } 224 kfree(areas); 225 fail_malloc_areas: 226 return NULL; 227 } 228 229 /* 230 * debug_info_alloc 231 * - alloc new debug-info 232 */ 233 static debug_info_t *debug_info_alloc(const char *name, int pages_per_area, 234 int nr_areas, int buf_size, int level, 235 int mode) 236 { 237 debug_info_t *rc; 238 239 /* alloc everything */ 240 rc = kmalloc(sizeof(debug_info_t), GFP_KERNEL); 241 if (!rc) 242 goto fail_malloc_rc; 243 rc->active_entries = kcalloc(nr_areas, sizeof(int), GFP_KERNEL); 244 if (!rc->active_entries) 245 goto fail_malloc_active_entries; 246 rc->active_pages = kcalloc(nr_areas, sizeof(int), GFP_KERNEL); 247 if (!rc->active_pages) 248 goto fail_malloc_active_pages; 249 if ((mode == ALL_AREAS) && (pages_per_area != 0)) { 250 rc->areas = debug_areas_alloc(pages_per_area, nr_areas); 251 if (!rc->areas) 252 goto fail_malloc_areas; 253 } else { 254 rc->areas = NULL; 255 } 256 257 /* initialize members */ 258 spin_lock_init(&rc->lock); 259 rc->pages_per_area = pages_per_area; 260 rc->nr_areas = nr_areas; 261 rc->active_area = 0; 262 rc->level = level; 263 rc->buf_size = buf_size; 264 rc->entry_size = sizeof(debug_entry_t) + buf_size; 265 strlcpy(rc->name, name, sizeof(rc->name)); 266 memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *)); 267 memset(rc->debugfs_entries, 0, DEBUG_MAX_VIEWS * sizeof(struct dentry *)); 268 refcount_set(&(rc->ref_count), 0); 269 270 return rc; 271 272 fail_malloc_areas: 273 kfree(rc->active_pages); 274 fail_malloc_active_pages: 275 kfree(rc->active_entries); 276 fail_malloc_active_entries: 277 kfree(rc); 278 fail_malloc_rc: 279 return NULL; 280 } 281 282 /* 283 * debug_areas_free 284 * - free all debug areas 285 */ 286 static void debug_areas_free(debug_info_t *db_info) 287 { 288 int i, j; 289 290 if (!db_info->areas) 291 return; 292 for (i = 0; i < db_info->nr_areas; i++) { 293 for (j = 0; j < db_info->pages_per_area; j++) 294 kfree(db_info->areas[i][j]); 295 kfree(db_info->areas[i]); 296 } 297 kfree(db_info->areas); 298 db_info->areas = NULL; 299 } 300 301 /* 302 * debug_info_free 303 * - free memory debug-info 304 */ 305 static void debug_info_free(debug_info_t *db_info) 306 { 307 debug_areas_free(db_info); 308 kfree(db_info->active_entries); 309 kfree(db_info->active_pages); 310 kfree(db_info); 311 } 312 313 /* 314 * debug_info_create 315 * - create new debug-info 316 */ 317 318 static debug_info_t *debug_info_create(const char *name, int pages_per_area, 319 int nr_areas, int buf_size, umode_t mode) 320 { 321 debug_info_t *rc; 322 323 rc = debug_info_alloc(name, pages_per_area, nr_areas, buf_size, 324 DEBUG_DEFAULT_LEVEL, ALL_AREAS); 325 if (!rc) 326 goto out; 327 328 rc->mode = mode & ~S_IFMT; 329 330 /* create root directory */ 331 rc->debugfs_root_entry = debugfs_create_dir(rc->name, 332 debug_debugfs_root_entry); 333 334 /* append new element to linked list */ 335 if (!debug_area_first) { 336 /* first element in list */ 337 debug_area_first = rc; 338 rc->prev = NULL; 339 } else { 340 /* append element to end of list */ 341 debug_area_last->next = rc; 342 rc->prev = debug_area_last; 343 } 344 debug_area_last = rc; 345 rc->next = NULL; 346 347 refcount_set(&rc->ref_count, 1); 348 out: 349 return rc; 350 } 351 352 /* 353 * debug_info_copy 354 * - copy debug-info 355 */ 356 static debug_info_t *debug_info_copy(debug_info_t *in, int mode) 357 { 358 unsigned long flags; 359 debug_info_t *rc; 360 int i, j; 361 362 /* get a consistent copy of the debug areas */ 363 do { 364 rc = debug_info_alloc(in->name, in->pages_per_area, 365 in->nr_areas, in->buf_size, in->level, mode); 366 spin_lock_irqsave(&in->lock, flags); 367 if (!rc) 368 goto out; 369 /* has something changed in the meantime ? */ 370 if ((rc->pages_per_area == in->pages_per_area) && 371 (rc->nr_areas == in->nr_areas)) { 372 break; 373 } 374 spin_unlock_irqrestore(&in->lock, flags); 375 debug_info_free(rc); 376 } while (1); 377 378 if (mode == NO_AREAS) 379 goto out; 380 381 for (i = 0; i < in->nr_areas; i++) { 382 for (j = 0; j < in->pages_per_area; j++) 383 memcpy(rc->areas[i][j], in->areas[i][j], PAGE_SIZE); 384 } 385 out: 386 spin_unlock_irqrestore(&in->lock, flags); 387 return rc; 388 } 389 390 /* 391 * debug_info_get 392 * - increments reference count for debug-info 393 */ 394 static void debug_info_get(debug_info_t *db_info) 395 { 396 if (db_info) 397 refcount_inc(&db_info->ref_count); 398 } 399 400 /* 401 * debug_info_put: 402 * - decreases reference count for debug-info and frees it if necessary 403 */ 404 static void debug_info_put(debug_info_t *db_info) 405 { 406 int i; 407 408 if (!db_info) 409 return; 410 if (refcount_dec_and_test(&db_info->ref_count)) { 411 for (i = 0; i < DEBUG_MAX_VIEWS; i++) { 412 if (!db_info->views[i]) 413 continue; 414 debugfs_remove(db_info->debugfs_entries[i]); 415 } 416 debugfs_remove(db_info->debugfs_root_entry); 417 if (db_info == debug_area_first) 418 debug_area_first = db_info->next; 419 if (db_info == debug_area_last) 420 debug_area_last = db_info->prev; 421 if (db_info->prev) 422 db_info->prev->next = db_info->next; 423 if (db_info->next) 424 db_info->next->prev = db_info->prev; 425 debug_info_free(db_info); 426 } 427 } 428 429 /* 430 * debug_format_entry: 431 * - format one debug entry and return size of formated data 432 */ 433 static int debug_format_entry(file_private_info_t *p_info) 434 { 435 debug_info_t *id_snap = p_info->debug_info_snap; 436 struct debug_view *view = p_info->view; 437 debug_entry_t *act_entry; 438 size_t len = 0; 439 440 if (p_info->act_entry == DEBUG_PROLOG_ENTRY) { 441 /* print prolog */ 442 if (view->prolog_proc) 443 len += view->prolog_proc(id_snap, view, p_info->temp_buf); 444 goto out; 445 } 446 if (!id_snap->areas) /* this is true, if we have a prolog only view */ 447 goto out; /* or if 'pages_per_area' is 0 */ 448 act_entry = (debug_entry_t *) ((char *)id_snap->areas[p_info->act_area] 449 [p_info->act_page] + p_info->act_entry); 450 451 if (act_entry->id.stck == 0LL) 452 goto out; /* empty entry */ 453 if (view->header_proc) 454 len += view->header_proc(id_snap, view, p_info->act_area, 455 act_entry, p_info->temp_buf + len); 456 if (view->format_proc) 457 len += view->format_proc(id_snap, view, p_info->temp_buf + len, 458 DEBUG_DATA(act_entry)); 459 out: 460 return len; 461 } 462 463 /* 464 * debug_next_entry: 465 * - goto next entry in p_info 466 */ 467 static inline int debug_next_entry(file_private_info_t *p_info) 468 { 469 debug_info_t *id; 470 471 id = p_info->debug_info_snap; 472 if (p_info->act_entry == DEBUG_PROLOG_ENTRY) { 473 p_info->act_entry = 0; 474 p_info->act_page = 0; 475 goto out; 476 } 477 if (!id->areas) 478 return 1; 479 p_info->act_entry += id->entry_size; 480 /* switch to next page, if we reached the end of the page */ 481 if (p_info->act_entry > (PAGE_SIZE - id->entry_size)) { 482 /* next page */ 483 p_info->act_entry = 0; 484 p_info->act_page += 1; 485 if ((p_info->act_page % id->pages_per_area) == 0) { 486 /* next area */ 487 p_info->act_area++; 488 p_info->act_page = 0; 489 } 490 if (p_info->act_area >= id->nr_areas) 491 return 1; 492 } 493 out: 494 return 0; 495 } 496 497 /* 498 * debug_output: 499 * - called for user read() 500 * - copies formated debug entries to the user buffer 501 */ 502 static ssize_t debug_output(struct file *file, /* file descriptor */ 503 char __user *user_buf, /* user buffer */ 504 size_t len, /* length of buffer */ 505 loff_t *offset) /* offset in the file */ 506 { 507 size_t count = 0; 508 size_t entry_offset; 509 file_private_info_t *p_info; 510 511 p_info = (file_private_info_t *) file->private_data; 512 if (*offset != p_info->offset) 513 return -EPIPE; 514 if (p_info->act_area >= p_info->debug_info_snap->nr_areas) 515 return 0; 516 entry_offset = p_info->act_entry_offset; 517 while (count < len) { 518 int formatted_line_residue; 519 int formatted_line_size; 520 int user_buf_residue; 521 size_t copy_size; 522 523 formatted_line_size = debug_format_entry(p_info); 524 formatted_line_residue = formatted_line_size - entry_offset; 525 user_buf_residue = len-count; 526 copy_size = min(user_buf_residue, formatted_line_residue); 527 if (copy_size) { 528 if (copy_to_user(user_buf + count, p_info->temp_buf 529 + entry_offset, copy_size)) 530 return -EFAULT; 531 count += copy_size; 532 entry_offset += copy_size; 533 } 534 if (copy_size == formatted_line_residue) { 535 entry_offset = 0; 536 if (debug_next_entry(p_info)) 537 goto out; 538 } 539 } 540 out: 541 p_info->offset = *offset + count; 542 p_info->act_entry_offset = entry_offset; 543 *offset = p_info->offset; 544 return count; 545 } 546 547 /* 548 * debug_input: 549 * - called for user write() 550 * - calls input function of view 551 */ 552 static ssize_t debug_input(struct file *file, const char __user *user_buf, 553 size_t length, loff_t *offset) 554 { 555 file_private_info_t *p_info; 556 int rc = 0; 557 558 mutex_lock(&debug_mutex); 559 p_info = ((file_private_info_t *) file->private_data); 560 if (p_info->view->input_proc) { 561 rc = p_info->view->input_proc(p_info->debug_info_org, 562 p_info->view, file, user_buf, 563 length, offset); 564 } else { 565 rc = -EPERM; 566 } 567 mutex_unlock(&debug_mutex); 568 return rc; /* number of input characters */ 569 } 570 571 /* 572 * debug_open: 573 * - called for user open() 574 * - copies formated output to private_data area of the file 575 * handle 576 */ 577 static int debug_open(struct inode *inode, struct file *file) 578 { 579 debug_info_t *debug_info, *debug_info_snapshot; 580 file_private_info_t *p_info; 581 int i, rc = 0; 582 583 mutex_lock(&debug_mutex); 584 debug_info = file_inode(file)->i_private; 585 /* find debug view */ 586 for (i = 0; i < DEBUG_MAX_VIEWS; i++) { 587 if (!debug_info->views[i]) 588 continue; 589 else if (debug_info->debugfs_entries[i] == file->f_path.dentry) 590 goto found; /* found view ! */ 591 } 592 /* no entry found */ 593 rc = -EINVAL; 594 goto out; 595 596 found: 597 598 /* Make snapshot of current debug areas to get it consistent. */ 599 /* To copy all the areas is only needed, if we have a view which */ 600 /* formats the debug areas. */ 601 602 if (!debug_info->views[i]->format_proc && !debug_info->views[i]->header_proc) 603 debug_info_snapshot = debug_info_copy(debug_info, NO_AREAS); 604 else 605 debug_info_snapshot = debug_info_copy(debug_info, ALL_AREAS); 606 607 if (!debug_info_snapshot) { 608 rc = -ENOMEM; 609 goto out; 610 } 611 p_info = kmalloc(sizeof(file_private_info_t), GFP_KERNEL); 612 if (!p_info) { 613 debug_info_free(debug_info_snapshot); 614 rc = -ENOMEM; 615 goto out; 616 } 617 p_info->offset = 0; 618 p_info->debug_info_snap = debug_info_snapshot; 619 p_info->debug_info_org = debug_info; 620 p_info->view = debug_info->views[i]; 621 p_info->act_area = 0; 622 p_info->act_page = 0; 623 p_info->act_entry = DEBUG_PROLOG_ENTRY; 624 p_info->act_entry_offset = 0; 625 file->private_data = p_info; 626 debug_info_get(debug_info); 627 nonseekable_open(inode, file); 628 out: 629 mutex_unlock(&debug_mutex); 630 return rc; 631 } 632 633 /* 634 * debug_close: 635 * - called for user close() 636 * - deletes private_data area of the file handle 637 */ 638 static int debug_close(struct inode *inode, struct file *file) 639 { 640 file_private_info_t *p_info; 641 642 p_info = (file_private_info_t *) file->private_data; 643 if (p_info->debug_info_snap) 644 debug_info_free(p_info->debug_info_snap); 645 debug_info_put(p_info->debug_info_org); 646 kfree(file->private_data); 647 return 0; /* success */ 648 } 649 650 /** 651 * debug_register_mode() - creates and initializes debug area. 652 * 653 * @name: Name of debug log (e.g. used for debugfs entry) 654 * @pages_per_area: Number of pages, which will be allocated per area 655 * @nr_areas: Number of debug areas 656 * @buf_size: Size of data area in each debug entry 657 * @mode: File mode for debugfs files. E.g. S_IRWXUGO 658 * @uid: User ID for debugfs files. Currently only 0 is supported. 659 * @gid: Group ID for debugfs files. Currently only 0 is supported. 660 * 661 * Return: 662 * - Handle for generated debug area 663 * - %NULL if register failed 664 * 665 * Allocates memory for a debug log. 666 * Must not be called within an interrupt handler. 667 */ 668 debug_info_t *debug_register_mode(const char *name, int pages_per_area, 669 int nr_areas, int buf_size, umode_t mode, 670 uid_t uid, gid_t gid) 671 { 672 debug_info_t *rc = NULL; 673 674 /* Since debugfs currently does not support uid/gid other than root, */ 675 /* we do not allow gid/uid != 0 until we get support for that. */ 676 if ((uid != 0) || (gid != 0)) 677 pr_warn("Root becomes the owner of all s390dbf files in sysfs\n"); 678 BUG_ON(!initialized); 679 mutex_lock(&debug_mutex); 680 681 /* create new debug_info */ 682 rc = debug_info_create(name, pages_per_area, nr_areas, buf_size, mode); 683 if (!rc) 684 goto out; 685 debug_register_view(rc, &debug_level_view); 686 debug_register_view(rc, &debug_flush_view); 687 debug_register_view(rc, &debug_pages_view); 688 out: 689 if (!rc) 690 pr_err("Registering debug feature %s failed\n", name); 691 mutex_unlock(&debug_mutex); 692 return rc; 693 } 694 EXPORT_SYMBOL(debug_register_mode); 695 696 /** 697 * debug_register() - creates and initializes debug area with default file mode. 698 * 699 * @name: Name of debug log (e.g. used for debugfs entry) 700 * @pages_per_area: Number of pages, which will be allocated per area 701 * @nr_areas: Number of debug areas 702 * @buf_size: Size of data area in each debug entry 703 * 704 * Return: 705 * - Handle for generated debug area 706 * - %NULL if register failed 707 * 708 * Allocates memory for a debug log. 709 * The debugfs file mode access permissions are read and write for user. 710 * Must not be called within an interrupt handler. 711 */ 712 debug_info_t *debug_register(const char *name, int pages_per_area, 713 int nr_areas, int buf_size) 714 { 715 return debug_register_mode(name, pages_per_area, nr_areas, buf_size, 716 S_IRUSR | S_IWUSR, 0, 0); 717 } 718 EXPORT_SYMBOL(debug_register); 719 720 /** 721 * debug_unregister() - give back debug area. 722 * 723 * @id: handle for debug log 724 * 725 * Return: 726 * none 727 */ 728 void debug_unregister(debug_info_t *id) 729 { 730 if (!id) 731 return; 732 mutex_lock(&debug_mutex); 733 debug_info_put(id); 734 mutex_unlock(&debug_mutex); 735 } 736 EXPORT_SYMBOL(debug_unregister); 737 738 /* 739 * debug_set_size: 740 * - set area size (number of pages) and number of areas 741 */ 742 static int debug_set_size(debug_info_t *id, int nr_areas, int pages_per_area) 743 { 744 debug_entry_t ***new_areas; 745 unsigned long flags; 746 int rc = 0; 747 748 if (!id || (nr_areas <= 0) || (pages_per_area < 0)) 749 return -EINVAL; 750 if (pages_per_area > 0) { 751 new_areas = debug_areas_alloc(pages_per_area, nr_areas); 752 if (!new_areas) { 753 pr_info("Allocating memory for %i pages failed\n", 754 pages_per_area); 755 rc = -ENOMEM; 756 goto out; 757 } 758 } else { 759 new_areas = NULL; 760 } 761 spin_lock_irqsave(&id->lock, flags); 762 debug_areas_free(id); 763 id->areas = new_areas; 764 id->nr_areas = nr_areas; 765 id->pages_per_area = pages_per_area; 766 id->active_area = 0; 767 memset(id->active_entries, 0, sizeof(int)*id->nr_areas); 768 memset(id->active_pages, 0, sizeof(int)*id->nr_areas); 769 spin_unlock_irqrestore(&id->lock, flags); 770 pr_info("%s: set new size (%i pages)\n", id->name, pages_per_area); 771 out: 772 return rc; 773 } 774 775 /** 776 * debug_set_level() - Sets new actual debug level if new_level is valid. 777 * 778 * @id: handle for debug log 779 * @new_level: new debug level 780 * 781 * Return: 782 * none 783 */ 784 void debug_set_level(debug_info_t *id, int new_level) 785 { 786 unsigned long flags; 787 788 if (!id) 789 return; 790 spin_lock_irqsave(&id->lock, flags); 791 if (new_level == DEBUG_OFF_LEVEL) { 792 id->level = DEBUG_OFF_LEVEL; 793 pr_info("%s: switched off\n", id->name); 794 } else if ((new_level > DEBUG_MAX_LEVEL) || (new_level < 0)) { 795 pr_info("%s: level %i is out of range (%i - %i)\n", 796 id->name, new_level, 0, DEBUG_MAX_LEVEL); 797 } else { 798 id->level = new_level; 799 } 800 spin_unlock_irqrestore(&id->lock, flags); 801 } 802 EXPORT_SYMBOL(debug_set_level); 803 804 /* 805 * proceed_active_entry: 806 * - set active entry to next in the ring buffer 807 */ 808 static inline void proceed_active_entry(debug_info_t *id) 809 { 810 if ((id->active_entries[id->active_area] += id->entry_size) 811 > (PAGE_SIZE - id->entry_size)) { 812 id->active_entries[id->active_area] = 0; 813 id->active_pages[id->active_area] = 814 (id->active_pages[id->active_area] + 1) % 815 id->pages_per_area; 816 } 817 } 818 819 /* 820 * proceed_active_area: 821 * - set active area to next in the ring buffer 822 */ 823 static inline void proceed_active_area(debug_info_t *id) 824 { 825 id->active_area++; 826 id->active_area = id->active_area % id->nr_areas; 827 } 828 829 /* 830 * get_active_entry: 831 */ 832 static inline debug_entry_t *get_active_entry(debug_info_t *id) 833 { 834 return (debug_entry_t *) (((char *) id->areas[id->active_area] 835 [id->active_pages[id->active_area]]) + 836 id->active_entries[id->active_area]); 837 } 838 839 /* 840 * debug_finish_entry: 841 * - set timestamp, caller address, cpu number etc. 842 */ 843 844 static inline void debug_finish_entry(debug_info_t *id, debug_entry_t *active, 845 int level, int exception) 846 { 847 active->id.stck = get_tod_clock_fast() - 848 *(unsigned long long *) &tod_clock_base[1]; 849 active->id.fields.cpuid = smp_processor_id(); 850 active->caller = __builtin_return_address(0); 851 active->id.fields.exception = exception; 852 active->id.fields.level = level; 853 proceed_active_entry(id); 854 if (exception) 855 proceed_active_area(id); 856 } 857 858 static int debug_stoppable = 1; 859 static int debug_active = 1; 860 861 #define CTL_S390DBF_STOPPABLE 5678 862 #define CTL_S390DBF_ACTIVE 5679 863 864 /* 865 * proc handler for the running debug_active sysctl 866 * always allow read, allow write only if debug_stoppable is set or 867 * if debug_active is already off 868 */ 869 static int s390dbf_procactive(struct ctl_table *table, int write, 870 void __user *buffer, size_t *lenp, loff_t *ppos) 871 { 872 if (!write || debug_stoppable || !debug_active) 873 return proc_dointvec(table, write, buffer, lenp, ppos); 874 else 875 return 0; 876 } 877 878 static struct ctl_table s390dbf_table[] = { 879 { 880 .procname = "debug_stoppable", 881 .data = &debug_stoppable, 882 .maxlen = sizeof(int), 883 .mode = S_IRUGO | S_IWUSR, 884 .proc_handler = proc_dointvec, 885 }, 886 { 887 .procname = "debug_active", 888 .data = &debug_active, 889 .maxlen = sizeof(int), 890 .mode = S_IRUGO | S_IWUSR, 891 .proc_handler = s390dbf_procactive, 892 }, 893 { } 894 }; 895 896 static struct ctl_table s390dbf_dir_table[] = { 897 { 898 .procname = "s390dbf", 899 .maxlen = 0, 900 .mode = S_IRUGO | S_IXUGO, 901 .child = s390dbf_table, 902 }, 903 { } 904 }; 905 906 static struct ctl_table_header *s390dbf_sysctl_header; 907 908 /** 909 * debug_stop_all() - stops the debug feature if stopping is allowed. 910 * 911 * Return: 912 * - none 913 * 914 * Currently used in case of a kernel oops. 915 */ 916 void debug_stop_all(void) 917 { 918 if (debug_stoppable) 919 debug_active = 0; 920 } 921 EXPORT_SYMBOL(debug_stop_all); 922 923 /** 924 * debug_set_critical() - event/exception functions try lock instead of spin. 925 * 926 * Return: 927 * - none 928 * 929 * Currently used in case of stopping all CPUs but the current one. 930 * Once in this state, functions to write a debug entry for an 931 * event or exception no longer spin on the debug area lock, 932 * but only try to get it and fail if they do not get the lock. 933 */ 934 void debug_set_critical(void) 935 { 936 debug_critical = 1; 937 } 938 939 /* 940 * debug_event_common: 941 * - write debug entry with given size 942 */ 943 debug_entry_t *debug_event_common(debug_info_t *id, int level, const void *buf, 944 int len) 945 { 946 debug_entry_t *active; 947 unsigned long flags; 948 949 if (!debug_active || !id->areas) 950 return NULL; 951 if (debug_critical) { 952 if (!spin_trylock_irqsave(&id->lock, flags)) 953 return NULL; 954 } else { 955 spin_lock_irqsave(&id->lock, flags); 956 } 957 do { 958 active = get_active_entry(id); 959 memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size)); 960 if (len < id->buf_size) 961 memset((DEBUG_DATA(active)) + len, 0, id->buf_size - len); 962 debug_finish_entry(id, active, level, 0); 963 len -= id->buf_size; 964 buf += id->buf_size; 965 } while (len > 0); 966 967 spin_unlock_irqrestore(&id->lock, flags); 968 return active; 969 } 970 EXPORT_SYMBOL(debug_event_common); 971 972 /* 973 * debug_exception_common: 974 * - write debug entry with given size and switch to next debug area 975 */ 976 debug_entry_t *debug_exception_common(debug_info_t *id, int level, 977 const void *buf, int len) 978 { 979 debug_entry_t *active; 980 unsigned long flags; 981 982 if (!debug_active || !id->areas) 983 return NULL; 984 if (debug_critical) { 985 if (!spin_trylock_irqsave(&id->lock, flags)) 986 return NULL; 987 } else { 988 spin_lock_irqsave(&id->lock, flags); 989 } 990 do { 991 active = get_active_entry(id); 992 memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size)); 993 if (len < id->buf_size) 994 memset((DEBUG_DATA(active)) + len, 0, id->buf_size - len); 995 debug_finish_entry(id, active, level, len <= id->buf_size); 996 len -= id->buf_size; 997 buf += id->buf_size; 998 } while (len > 0); 999 1000 spin_unlock_irqrestore(&id->lock, flags); 1001 return active; 1002 } 1003 EXPORT_SYMBOL(debug_exception_common); 1004 1005 /* 1006 * counts arguments in format string for sprintf view 1007 */ 1008 static inline int debug_count_numargs(char *string) 1009 { 1010 int numargs = 0; 1011 1012 while (*string) { 1013 if (*string++ == '%') 1014 numargs++; 1015 } 1016 return numargs; 1017 } 1018 1019 /* 1020 * debug_sprintf_event: 1021 */ 1022 debug_entry_t *__debug_sprintf_event(debug_info_t *id, int level, char *string, ...) 1023 { 1024 debug_sprintf_entry_t *curr_event; 1025 debug_entry_t *active; 1026 unsigned long flags; 1027 int numargs, idx; 1028 va_list ap; 1029 1030 if (!debug_active || !id->areas) 1031 return NULL; 1032 numargs = debug_count_numargs(string); 1033 1034 if (debug_critical) { 1035 if (!spin_trylock_irqsave(&id->lock, flags)) 1036 return NULL; 1037 } else { 1038 spin_lock_irqsave(&id->lock, flags); 1039 } 1040 active = get_active_entry(id); 1041 curr_event = (debug_sprintf_entry_t *) DEBUG_DATA(active); 1042 va_start(ap, string); 1043 curr_event->string = string; 1044 for (idx = 0; idx < min(numargs, (int)(id->buf_size / sizeof(long)) - 1); idx++) 1045 curr_event->args[idx] = va_arg(ap, long); 1046 va_end(ap); 1047 debug_finish_entry(id, active, level, 0); 1048 spin_unlock_irqrestore(&id->lock, flags); 1049 1050 return active; 1051 } 1052 EXPORT_SYMBOL(__debug_sprintf_event); 1053 1054 /* 1055 * debug_sprintf_exception: 1056 */ 1057 debug_entry_t *__debug_sprintf_exception(debug_info_t *id, int level, char *string, ...) 1058 { 1059 debug_sprintf_entry_t *curr_event; 1060 debug_entry_t *active; 1061 unsigned long flags; 1062 int numargs, idx; 1063 va_list ap; 1064 1065 if (!debug_active || !id->areas) 1066 return NULL; 1067 1068 numargs = debug_count_numargs(string); 1069 1070 if (debug_critical) { 1071 if (!spin_trylock_irqsave(&id->lock, flags)) 1072 return NULL; 1073 } else { 1074 spin_lock_irqsave(&id->lock, flags); 1075 } 1076 active = get_active_entry(id); 1077 curr_event = (debug_sprintf_entry_t *)DEBUG_DATA(active); 1078 va_start(ap, string); 1079 curr_event->string = string; 1080 for (idx = 0; idx < min(numargs, (int)(id->buf_size / sizeof(long)) - 1); idx++) 1081 curr_event->args[idx] = va_arg(ap, long); 1082 va_end(ap); 1083 debug_finish_entry(id, active, level, 1); 1084 spin_unlock_irqrestore(&id->lock, flags); 1085 1086 return active; 1087 } 1088 EXPORT_SYMBOL(__debug_sprintf_exception); 1089 1090 /** 1091 * debug_register_view() - registers new debug view and creates debugfs 1092 * dir entry 1093 * 1094 * @id: handle for debug log 1095 * @view: pointer to debug view struct 1096 * 1097 * Return: 1098 * - 0 : ok 1099 * - < 0: Error 1100 */ 1101 int debug_register_view(debug_info_t *id, struct debug_view *view) 1102 { 1103 unsigned long flags; 1104 struct dentry *pde; 1105 umode_t mode; 1106 int rc = 0; 1107 int i; 1108 1109 if (!id) 1110 goto out; 1111 mode = (id->mode | S_IFREG) & ~S_IXUGO; 1112 if (!(view->prolog_proc || view->format_proc || view->header_proc)) 1113 mode &= ~(S_IRUSR | S_IRGRP | S_IROTH); 1114 if (!view->input_proc) 1115 mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH); 1116 pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry, 1117 id, &debug_file_ops); 1118 spin_lock_irqsave(&id->lock, flags); 1119 for (i = 0; i < DEBUG_MAX_VIEWS; i++) { 1120 if (!id->views[i]) 1121 break; 1122 } 1123 if (i == DEBUG_MAX_VIEWS) { 1124 pr_err("Registering view %s/%s would exceed the maximum " 1125 "number of views %i\n", id->name, view->name, i); 1126 rc = -1; 1127 } else { 1128 id->views[i] = view; 1129 id->debugfs_entries[i] = pde; 1130 } 1131 spin_unlock_irqrestore(&id->lock, flags); 1132 if (rc) 1133 debugfs_remove(pde); 1134 out: 1135 return rc; 1136 } 1137 EXPORT_SYMBOL(debug_register_view); 1138 1139 /** 1140 * debug_unregister_view() - unregisters debug view and removes debugfs 1141 * dir entry 1142 * 1143 * @id: handle for debug log 1144 * @view: pointer to debug view struct 1145 * 1146 * Return: 1147 * - 0 : ok 1148 * - < 0: Error 1149 */ 1150 int debug_unregister_view(debug_info_t *id, struct debug_view *view) 1151 { 1152 struct dentry *dentry = NULL; 1153 unsigned long flags; 1154 int i, rc = 0; 1155 1156 if (!id) 1157 goto out; 1158 spin_lock_irqsave(&id->lock, flags); 1159 for (i = 0; i < DEBUG_MAX_VIEWS; i++) { 1160 if (id->views[i] == view) 1161 break; 1162 } 1163 if (i == DEBUG_MAX_VIEWS) { 1164 rc = -1; 1165 } else { 1166 dentry = id->debugfs_entries[i]; 1167 id->views[i] = NULL; 1168 id->debugfs_entries[i] = NULL; 1169 } 1170 spin_unlock_irqrestore(&id->lock, flags); 1171 debugfs_remove(dentry); 1172 out: 1173 return rc; 1174 } 1175 EXPORT_SYMBOL(debug_unregister_view); 1176 1177 static inline char *debug_get_user_string(const char __user *user_buf, 1178 size_t user_len) 1179 { 1180 char *buffer; 1181 1182 buffer = kmalloc(user_len + 1, GFP_KERNEL); 1183 if (!buffer) 1184 return ERR_PTR(-ENOMEM); 1185 if (copy_from_user(buffer, user_buf, user_len) != 0) { 1186 kfree(buffer); 1187 return ERR_PTR(-EFAULT); 1188 } 1189 /* got the string, now strip linefeed. */ 1190 if (buffer[user_len - 1] == '\n') 1191 buffer[user_len - 1] = 0; 1192 else 1193 buffer[user_len] = 0; 1194 return buffer; 1195 } 1196 1197 static inline int debug_get_uint(char *buf) 1198 { 1199 int rc; 1200 1201 buf = skip_spaces(buf); 1202 rc = simple_strtoul(buf, &buf, 10); 1203 if (*buf) 1204 rc = -EINVAL; 1205 return rc; 1206 } 1207 1208 /* 1209 * functions for debug-views 1210 *********************************** 1211 */ 1212 1213 /* 1214 * prints out actual debug level 1215 */ 1216 1217 static int debug_prolog_pages_fn(debug_info_t *id, struct debug_view *view, 1218 char *out_buf) 1219 { 1220 return sprintf(out_buf, "%i\n", id->pages_per_area); 1221 } 1222 1223 /* 1224 * reads new size (number of pages per debug area) 1225 */ 1226 1227 static int debug_input_pages_fn(debug_info_t *id, struct debug_view *view, 1228 struct file *file, const char __user *user_buf, 1229 size_t user_len, loff_t *offset) 1230 { 1231 int rc, new_pages; 1232 char *str; 1233 1234 if (user_len > 0x10000) 1235 user_len = 0x10000; 1236 if (*offset != 0) { 1237 rc = -EPIPE; 1238 goto out; 1239 } 1240 str = debug_get_user_string(user_buf, user_len); 1241 if (IS_ERR(str)) { 1242 rc = PTR_ERR(str); 1243 goto out; 1244 } 1245 new_pages = debug_get_uint(str); 1246 if (new_pages < 0) { 1247 rc = -EINVAL; 1248 goto free_str; 1249 } 1250 rc = debug_set_size(id, id->nr_areas, new_pages); 1251 if (rc != 0) { 1252 rc = -EINVAL; 1253 goto free_str; 1254 } 1255 rc = user_len; 1256 free_str: 1257 kfree(str); 1258 out: 1259 *offset += user_len; 1260 return rc; /* number of input characters */ 1261 } 1262 1263 /* 1264 * prints out actual debug level 1265 */ 1266 static int debug_prolog_level_fn(debug_info_t *id, struct debug_view *view, 1267 char *out_buf) 1268 { 1269 int rc = 0; 1270 1271 if (id->level == DEBUG_OFF_LEVEL) 1272 rc = sprintf(out_buf, "-\n"); 1273 else 1274 rc = sprintf(out_buf, "%i\n", id->level); 1275 return rc; 1276 } 1277 1278 /* 1279 * reads new debug level 1280 */ 1281 static int debug_input_level_fn(debug_info_t *id, struct debug_view *view, 1282 struct file *file, const char __user *user_buf, 1283 size_t user_len, loff_t *offset) 1284 { 1285 int rc, new_level; 1286 char *str; 1287 1288 if (user_len > 0x10000) 1289 user_len = 0x10000; 1290 if (*offset != 0) { 1291 rc = -EPIPE; 1292 goto out; 1293 } 1294 str = debug_get_user_string(user_buf, user_len); 1295 if (IS_ERR(str)) { 1296 rc = PTR_ERR(str); 1297 goto out; 1298 } 1299 if (str[0] == '-') { 1300 debug_set_level(id, DEBUG_OFF_LEVEL); 1301 rc = user_len; 1302 goto free_str; 1303 } else { 1304 new_level = debug_get_uint(str); 1305 } 1306 if (new_level < 0) { 1307 pr_warn("%s is not a valid level for a debug feature\n", str); 1308 rc = -EINVAL; 1309 } else { 1310 debug_set_level(id, new_level); 1311 rc = user_len; 1312 } 1313 free_str: 1314 kfree(str); 1315 out: 1316 *offset += user_len; 1317 return rc; /* number of input characters */ 1318 } 1319 1320 /* 1321 * flushes debug areas 1322 */ 1323 static void debug_flush(debug_info_t *id, int area) 1324 { 1325 unsigned long flags; 1326 int i, j; 1327 1328 if (!id || !id->areas) 1329 return; 1330 spin_lock_irqsave(&id->lock, flags); 1331 if (area == DEBUG_FLUSH_ALL) { 1332 id->active_area = 0; 1333 memset(id->active_entries, 0, id->nr_areas * sizeof(int)); 1334 for (i = 0; i < id->nr_areas; i++) { 1335 id->active_pages[i] = 0; 1336 for (j = 0; j < id->pages_per_area; j++) 1337 memset(id->areas[i][j], 0, PAGE_SIZE); 1338 } 1339 } else if (area >= 0 && area < id->nr_areas) { 1340 id->active_entries[area] = 0; 1341 id->active_pages[area] = 0; 1342 for (i = 0; i < id->pages_per_area; i++) 1343 memset(id->areas[area][i], 0, PAGE_SIZE); 1344 } 1345 spin_unlock_irqrestore(&id->lock, flags); 1346 } 1347 1348 /* 1349 * view function: flushes debug areas 1350 */ 1351 static int debug_input_flush_fn(debug_info_t *id, struct debug_view *view, 1352 struct file *file, const char __user *user_buf, 1353 size_t user_len, loff_t *offset) 1354 { 1355 char input_buf[1]; 1356 int rc = user_len; 1357 1358 if (user_len > 0x10000) 1359 user_len = 0x10000; 1360 if (*offset != 0) { 1361 rc = -EPIPE; 1362 goto out; 1363 } 1364 if (copy_from_user(input_buf, user_buf, 1)) { 1365 rc = -EFAULT; 1366 goto out; 1367 } 1368 if (input_buf[0] == '-') { 1369 debug_flush(id, DEBUG_FLUSH_ALL); 1370 goto out; 1371 } 1372 if (isdigit(input_buf[0])) { 1373 int area = ((int) input_buf[0] - (int) '0'); 1374 1375 debug_flush(id, area); 1376 goto out; 1377 } 1378 1379 pr_info("Flushing debug data failed because %c is not a valid " 1380 "area\n", input_buf[0]); 1381 1382 out: 1383 *offset += user_len; 1384 return rc; /* number of input characters */ 1385 } 1386 1387 /* 1388 * prints debug header in raw format 1389 */ 1390 static int debug_raw_header_fn(debug_info_t *id, struct debug_view *view, 1391 int area, debug_entry_t *entry, char *out_buf) 1392 { 1393 int rc; 1394 1395 rc = sizeof(debug_entry_t); 1396 memcpy(out_buf, entry, sizeof(debug_entry_t)); 1397 return rc; 1398 } 1399 1400 /* 1401 * prints debug data in raw format 1402 */ 1403 static int debug_raw_format_fn(debug_info_t *id, struct debug_view *view, 1404 char *out_buf, const char *in_buf) 1405 { 1406 int rc; 1407 1408 rc = id->buf_size; 1409 memcpy(out_buf, in_buf, id->buf_size); 1410 return rc; 1411 } 1412 1413 /* 1414 * prints debug data in hex/ascii format 1415 */ 1416 static int debug_hex_ascii_format_fn(debug_info_t *id, struct debug_view *view, 1417 char *out_buf, const char *in_buf) 1418 { 1419 int i, rc = 0; 1420 1421 for (i = 0; i < id->buf_size; i++) 1422 rc += sprintf(out_buf + rc, "%02x ", ((unsigned char *) in_buf)[i]); 1423 rc += sprintf(out_buf + rc, "| "); 1424 for (i = 0; i < id->buf_size; i++) { 1425 unsigned char c = in_buf[i]; 1426 1427 if (isascii(c) && isprint(c)) 1428 rc += sprintf(out_buf + rc, "%c", c); 1429 else 1430 rc += sprintf(out_buf + rc, "."); 1431 } 1432 rc += sprintf(out_buf + rc, "\n"); 1433 return rc; 1434 } 1435 1436 /* 1437 * prints header for debug entry 1438 */ 1439 int debug_dflt_header_fn(debug_info_t *id, struct debug_view *view, 1440 int area, debug_entry_t *entry, char *out_buf) 1441 { 1442 unsigned long base, sec, usec; 1443 unsigned long caller; 1444 unsigned int level; 1445 char *except_str; 1446 int rc = 0; 1447 1448 level = entry->id.fields.level; 1449 base = (*(unsigned long *) &tod_clock_base[0]) >> 4; 1450 sec = (entry->id.stck >> 12) + base - (TOD_UNIX_EPOCH >> 12); 1451 usec = do_div(sec, USEC_PER_SEC); 1452 1453 if (entry->id.fields.exception) 1454 except_str = "*"; 1455 else 1456 except_str = "-"; 1457 caller = (unsigned long) entry->caller; 1458 rc += sprintf(out_buf, "%02i %011ld:%06lu %1u %1s %02i %pK ", 1459 area, sec, usec, level, except_str, 1460 entry->id.fields.cpuid, (void *)caller); 1461 return rc; 1462 } 1463 EXPORT_SYMBOL(debug_dflt_header_fn); 1464 1465 /* 1466 * prints debug data sprintf-formated: 1467 * debug_sprinf_event/exception calls must be used together with this view 1468 */ 1469 1470 #define DEBUG_SPRINTF_MAX_ARGS 10 1471 1472 static int 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 out: 1505 return rc; 1506 } 1507 1508 /* 1509 * debug_init: 1510 * - is called exactly once to initialize the debug feature 1511 */ 1512 static int __init debug_init(void) 1513 { 1514 s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table); 1515 mutex_lock(&debug_mutex); 1516 debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT, NULL); 1517 initialized = 1; 1518 mutex_unlock(&debug_mutex); 1519 return 0; 1520 } 1521 postcore_initcall(debug_init); 1522