arch/s390/kernel/debug.c

   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 DEFINE_MUTEX(debug_mutex);
 167
 168 static int initialized;
 169
 170 static const 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));
 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         mutex_lock(&debug_mutex);
 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         mutex_unlock(&debug_mutex);
 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         mutex_lock(&debug_mutex);
 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         mutex_unlock(&debug_mutex);
 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         mutex_lock(&debug_mutex);
 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         mutex_unlock(&debug_mutex);
 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         mutex_lock(&debug_mutex);
 720         debug_info_put(id);
 721         mutex_unlock(&debug_mutex);
 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_STOPPABLE 5678
 856 #define CTL_S390DBF_ACTIVE 5679
 857
 858 /*
 859  * proc handler for the running debug_active sysctl
 860  * always allow read, allow write only if debug_stoppable is set or
 861  * if debug_active is already off
 862  */
 863 static int
 864 s390dbf_procactive(ctl_table *table, int write, struct file *filp,
 865                      void __user *buffer, size_t *lenp, loff_t *ppos)
 866 {
 867         if (!write || debug_stoppable || !debug_active)
 868                 return proc_dointvec(table, write, filp, buffer, lenp, ppos);
 869         else
 870                 return 0;
 871 }
 872
 873
 874 static struct ctl_table s390dbf_table[] = {
 875         {
 876                 .ctl_name       = CTL_S390DBF_STOPPABLE,
 877                 .procname       = "debug_stoppable",
 878                 .data           = &debug_stoppable,
 879                 .maxlen         = sizeof(int),
 880                 .mode           = S_IRUGO | S_IWUSR,
 881                 .proc_handler   = &proc_dointvec,
 882                 .strategy       = &sysctl_intvec,
 883         },
 884          {
 885                 .ctl_name       = CTL_S390DBF_ACTIVE,
 886                 .procname       = "debug_active",
 887                 .data           = &debug_active,
 888                 .maxlen         = sizeof(int),
 889                 .mode           = S_IRUGO | S_IWUSR,
 890                 .proc_handler   = &s390dbf_procactive,
 891                 .strategy       = &sysctl_intvec,
 892         },
 893         { .ctl_name = 0 }
 894 };
 895
 896 static struct ctl_table s390dbf_dir_table[] = {
 897         {
 898                 .ctl_name       = CTL_S390DBF,
 899                 .procname       = "s390dbf",
 900                 .maxlen         = 0,
 901                 .mode           = S_IRUGO | S_IXUGO,
 902                 .child          = s390dbf_table,
 903         },
 904         { .ctl_name = 0 }
 905 };
 906
 907 static struct ctl_table_header *s390dbf_sysctl_header;
 908
 909 void
 910 debug_stop_all(void)
 911 {
 912         if (debug_stoppable)
 913                 debug_active = 0;
 914 }
 915
 916
 917 /*
 918  * debug_event_common:
 919  * - write debug entry with given size
 920  */
 921
 922 debug_entry_t*
 923 debug_event_common(debug_info_t * id, int level, const void *buf, int len)
 924 {
 925         unsigned long flags;
 926         debug_entry_t *active;
 927
 928         if (!debug_active || !id->areas)
 929                 return NULL;
 930         spin_lock_irqsave(&id->lock, flags);
 931         active = get_active_entry(id);
 932         memset(DEBUG_DATA(active), 0, id->buf_size);
 933         memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
 934         debug_finish_entry(id, active, level, 0);
 935         spin_unlock_irqrestore(&id->lock, flags);
 936
 937         return active;
 938 }
 939
 940 /*
 941  * debug_exception_common:
 942  * - write debug entry with given size and switch to next debug area
 943  */
 944
 945 debug_entry_t
 946 *debug_exception_common(debug_info_t * id, int level, const void *buf, int len)
 947 {
 948         unsigned long flags;
 949         debug_entry_t *active;
 950
 951         if (!debug_active || !id->areas)
 952                 return NULL;
 953         spin_lock_irqsave(&id->lock, flags);
 954         active = get_active_entry(id);
 955         memset(DEBUG_DATA(active), 0, id->buf_size);
 956         memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
 957         debug_finish_entry(id, active, level, 1);
 958         spin_unlock_irqrestore(&id->lock, flags);
 959
 960         return active;
 961 }
 962
 963 /*
 964  * counts arguments in format string for sprintf view
 965  */
 966
 967 static inline int
 968 debug_count_numargs(char *string)
 969 {
 970         int numargs=0;
 971
 972         while(*string) {
 973                 if(*string++=='%')
 974                         numargs++;
 975         }
 976         return(numargs);
 977 }
 978
 979 /*
 980  * debug_sprintf_event:
 981  */
 982
 983 debug_entry_t*
 984 debug_sprintf_event(debug_info_t* id, int level,char *string,...)
 985 {
 986         va_list   ap;
 987         int numargs,idx;
 988         unsigned long flags;
 989         debug_sprintf_entry_t *curr_event;
 990         debug_entry_t *active;
 991
 992         if((!id) || (level > id->level))
 993                 return NULL;
 994         if (!debug_active || !id->areas)
 995                 return NULL;
 996         numargs=debug_count_numargs(string);
 997
 998         spin_lock_irqsave(&id->lock, flags);
 999         active = get_active_entry(id);
1000         curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active);
1001         va_start(ap,string);
1002         curr_event->string=string;
1003         for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
1004                 curr_event->args[idx]=va_arg(ap,long);
1005         va_end(ap);
1006         debug_finish_entry(id, active, level, 0);
1007         spin_unlock_irqrestore(&id->lock, flags);
1008
1009         return active;
1010 }
1011
1012 /*
1013  * debug_sprintf_exception:
1014  */
1015
1016 debug_entry_t*
1017 debug_sprintf_exception(debug_info_t* id, int level,char *string,...)
1018 {
1019         va_list   ap;
1020         int numargs,idx;
1021         unsigned long flags;
1022         debug_sprintf_entry_t *curr_event;
1023         debug_entry_t *active;
1024
1025         if((!id) || (level > id->level))
1026                 return NULL;
1027         if (!debug_active || !id->areas)
1028                 return NULL;
1029
1030         numargs=debug_count_numargs(string);
1031
1032         spin_lock_irqsave(&id->lock, flags);
1033         active = get_active_entry(id);
1034         curr_event=(debug_sprintf_entry_t *)DEBUG_DATA(active);
1035         va_start(ap,string);
1036         curr_event->string=string;
1037         for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
1038                 curr_event->args[idx]=va_arg(ap,long);
1039         va_end(ap);
1040         debug_finish_entry(id, active, level, 1);
1041         spin_unlock_irqrestore(&id->lock, flags);
1042
1043         return active;
1044 }
1045
1046 /*
1047  * debug_init:
1048  * - is called exactly once to initialize the debug feature
1049  */
1050
1051 static int
1052 __init debug_init(void)
1053 {
1054         int rc = 0;
1055
1056         s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table);
1057         mutex_lock(&debug_mutex);
1058         debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT,NULL);
1059         printk(KERN_INFO "debug: Initialization complete\n");
1060         initialized = 1;
1061         mutex_unlock(&debug_mutex);
1062
1063         return rc;
1064 }
1065
1066 /*
1067  * debug_register_view:
1068  */
1069
1070 int
1071 debug_register_view(debug_info_t * id, struct debug_view *view)
1072 {
1073         int rc = 0;
1074         int i;
1075         unsigned long flags;
1076         mode_t mode = S_IFREG;
1077         struct dentry *pde;
1078
1079         if (!id)
1080                 goto out;
1081         if (view->prolog_proc || view->format_proc || view->header_proc)
1082                 mode |= S_IRUSR;
1083         if (view->input_proc)
1084                 mode |= S_IWUSR;
1085         pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry,
1086                                 id , &debug_file_ops);
1087         if (!pde){
1088                 printk(KERN_WARNING "debug: debugfs_create_file() failed!"\
1089                         " Cannot register view %s/%s\n", id->name,view->name);
1090                 rc = -1;
1091                 goto out;
1092         }
1093         spin_lock_irqsave(&id->lock, flags);
1094         for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1095                 if (!id->views[i])
1096                         break;
1097         }
1098         if (i == DEBUG_MAX_VIEWS) {
1099                 printk(KERN_WARNING "debug: cannot register view %s/%s\n",
1100                         id->name,view->name);
1101                 printk(KERN_WARNING
1102                         "debug: maximum number of views reached (%i)!\n", i);
1103                 debugfs_remove(pde);
1104                 rc = -1;
1105         } else {
1106                 id->views[i] = view;
1107                 id->debugfs_entries[i] = pde;
1108         }
1109         spin_unlock_irqrestore(&id->lock, flags);
1110 out:
1111         return rc;
1112 }
1113
1114 /*
1115  * debug_unregister_view:
1116  */
1117
1118 int
1119 debug_unregister_view(debug_info_t * id, struct debug_view *view)
1120 {
1121         int rc = 0;
1122         int i;
1123         unsigned long flags;
1124
1125         if (!id)
1126                 goto out;
1127         spin_lock_irqsave(&id->lock, flags);
1128         for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1129                 if (id->views[i] == view)
1130                         break;
1131         }
1132         if (i == DEBUG_MAX_VIEWS)
1133                 rc = -1;
1134         else {
1135                 debugfs_remove(id->debugfs_entries[i]);
1136                 id->views[i] = NULL;
1137                 rc = 0;
1138         }
1139         spin_unlock_irqrestore(&id->lock, flags);
1140 out:
1141         return rc;
1142 }
1143
1144 static inline char *
1145 debug_get_user_string(const char __user *user_buf, size_t user_len)
1146 {
1147         char* buffer;
1148
1149         buffer = kmalloc(user_len + 1, GFP_KERNEL);
1150         if (!buffer)
1151                 return ERR_PTR(-ENOMEM);
1152         if (copy_from_user(buffer, user_buf, user_len) != 0) {
1153                 kfree(buffer);
1154                 return ERR_PTR(-EFAULT);
1155         }
1156         /* got the string, now strip linefeed. */
1157         if (buffer[user_len - 1] == '\n')
1158                 buffer[user_len - 1] = 0;
1159         else
1160                 buffer[user_len] = 0;
1161         return buffer;
1162 }
1163
1164 static inline int
1165 debug_get_uint(char *buf)
1166 {
1167         int rc;
1168
1169         for(; isspace(*buf); buf++);
1170         rc = simple_strtoul(buf, &buf, 10);
1171         if(*buf){
1172                 printk("debug: no integer specified!\n");
1173                 rc = -EINVAL;
1174         }
1175         return rc;
1176 }
1177
1178 /*
1179  * functions for debug-views
1180  ***********************************
1181 */
1182
1183 /*
1184  * prints out actual debug level
1185  */
1186
1187 static int
1188 debug_prolog_pages_fn(debug_info_t * id,
1189                                  struct debug_view *view, char *out_buf)
1190 {
1191         return sprintf(out_buf, "%i\n", id->pages_per_area);
1192 }
1193
1194 /*
1195  * reads new size (number of pages per debug area)
1196  */
1197
1198 static int
1199 debug_input_pages_fn(debug_info_t * id, struct debug_view *view,
1200                         struct file *file, const char __user *user_buf,
1201                         size_t user_len, loff_t * offset)
1202 {
1203         char *str;
1204         int rc,new_pages;
1205
1206         if (user_len > 0x10000)
1207                 user_len = 0x10000;
1208         if (*offset != 0){
1209                 rc = -EPIPE;
1210                 goto out;
1211         }
1212         str = debug_get_user_string(user_buf,user_len);
1213         if(IS_ERR(str)){
1214                 rc = PTR_ERR(str);
1215                 goto out;
1216         }
1217         new_pages = debug_get_uint(str);
1218         if(new_pages < 0){
1219                 rc = -EINVAL;
1220                 goto free_str;
1221         }
1222         rc = debug_set_size(id,id->nr_areas, new_pages);
1223         if(rc != 0){
1224                 rc = -EINVAL;
1225                 goto free_str;
1226         }
1227         rc = user_len;
1228 free_str:
1229         kfree(str);
1230 out:
1231         *offset += user_len;
1232         return rc;              /* number of input characters */
1233 }
1234
1235 /*
1236  * prints out actual debug level
1237  */
1238
1239 static int
1240 debug_prolog_level_fn(debug_info_t * id, struct debug_view *view, char *out_buf)
1241 {
1242         int rc = 0;
1243
1244         if(id->level == DEBUG_OFF_LEVEL) {
1245                 rc = sprintf(out_buf,"-\n");
1246         }
1247         else {
1248                 rc = sprintf(out_buf, "%i\n", id->level);
1249         }
1250         return rc;
1251 }
1252
1253 /*
1254  * reads new debug level
1255  */
1256
1257 static int
1258 debug_input_level_fn(debug_info_t * id, struct debug_view *view,
1259                         struct file *file, const char __user *user_buf,
1260                         size_t user_len, loff_t * offset)
1261 {
1262         char *str;
1263         int rc,new_level;
1264
1265         if (user_len > 0x10000)
1266                 user_len = 0x10000;
1267         if (*offset != 0){
1268                 rc = -EPIPE;
1269                 goto out;
1270         }
1271         str = debug_get_user_string(user_buf,user_len);
1272         if(IS_ERR(str)){
1273                 rc = PTR_ERR(str);
1274                 goto out;
1275         }
1276         if(str[0] == '-'){
1277                 debug_set_level(id, DEBUG_OFF_LEVEL);
1278                 rc = user_len;
1279                 goto free_str;
1280         } else {
1281                 new_level = debug_get_uint(str);
1282         }
1283         if(new_level < 0) {
1284                 printk(KERN_INFO "debug: level `%s` is not valid\n", str);
1285                 rc = -EINVAL;
1286         } else {
1287                 debug_set_level(id, new_level);
1288                 rc = user_len;
1289         }
1290 free_str:
1291         kfree(str);
1292 out:
1293         *offset += user_len;
1294         return rc;              /* number of input characters */
1295 }
1296
1297
1298 /*
1299  * flushes debug areas
1300  */
1301
1302 static void debug_flush(debug_info_t* id, int area)
1303 {
1304         unsigned long flags;
1305         int i,j;
1306
1307         if(!id || !id->areas)
1308                 return;
1309         spin_lock_irqsave(&id->lock,flags);
1310         if(area == DEBUG_FLUSH_ALL){
1311                 id->active_area = 0;
1312                 memset(id->active_entries, 0, id->nr_areas * sizeof(int));
1313                 for (i = 0; i < id->nr_areas; i++) {
1314                         id->active_pages[i] = 0;
1315                         for(j = 0; j < id->pages_per_area; j++) {
1316                                 memset(id->areas[i][j], 0, PAGE_SIZE);
1317                         }
1318                 }
1319                 printk(KERN_INFO "debug: %s: all areas flushed\n",id->name);
1320         } else if(area >= 0 && area < id->nr_areas) {
1321                 id->active_entries[area] = 0;
1322                 id->active_pages[area] = 0;
1323                 for(i = 0; i < id->pages_per_area; i++) {
1324                         memset(id->areas[area][i],0,PAGE_SIZE);
1325                 }
1326                 printk(KERN_INFO "debug: %s: area %i has been flushed\n",
1327                         id->name, area);
1328         } else {
1329                 printk(KERN_INFO
1330                       "debug: %s: area %i cannot be flushed (range: %i - %i)\n",
1331                         id->name, area, 0, id->nr_areas-1);
1332         }
1333         spin_unlock_irqrestore(&id->lock,flags);
1334 }
1335
1336 /*
1337  * view function: flushes debug areas
1338  */
1339
1340 static int
1341 debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
1342                         struct file *file, const char __user *user_buf,
1343                         size_t user_len, loff_t * offset)
1344 {
1345         char input_buf[1];
1346         int rc = user_len;
1347
1348         if (user_len > 0x10000)
1349                 user_len = 0x10000;
1350         if (*offset != 0){
1351                 rc = -EPIPE;
1352                 goto out;
1353         }
1354         if (copy_from_user(input_buf, user_buf, 1)){
1355                 rc = -EFAULT;
1356                 goto out;
1357         }
1358         if(input_buf[0] == '-') {
1359                 debug_flush(id, DEBUG_FLUSH_ALL);
1360                 goto out;
1361         }
1362         if (isdigit(input_buf[0])) {
1363                 int area = ((int) input_buf[0] - (int) '0');
1364                 debug_flush(id, area);
1365                 goto out;
1366         }
1367
1368         printk(KERN_INFO "debug: area `%c` is not valid\n", input_buf[0]);
1369
1370 out:
1371         *offset += user_len;
1372         return rc;              /* number of input characters */
1373 }
1374
1375 /*
1376  * prints debug header in raw format
1377  */
1378
1379 static int
1380 debug_raw_header_fn(debug_info_t * id, struct debug_view *view,
1381                         int area, debug_entry_t * entry, char *out_buf)
1382 {
1383         int rc;
1384
1385         rc = sizeof(debug_entry_t);
1386         memcpy(out_buf,entry,sizeof(debug_entry_t));
1387         return rc;
1388 }
1389
1390 /*
1391  * prints debug data in raw format
1392  */
1393
1394 static int
1395 debug_raw_format_fn(debug_info_t * id, struct debug_view *view,
1396                                char *out_buf, const char *in_buf)
1397 {
1398         int rc;
1399
1400         rc = id->buf_size;
1401         memcpy(out_buf, in_buf, id->buf_size);
1402         return rc;
1403 }
1404
1405 /*
1406  * prints debug data in hex/ascii format
1407  */
1408
1409 static int
1410 debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
1411                           char *out_buf, const char *in_buf)
1412 {
1413         int i, rc = 0;
1414
1415         for (i = 0; i < id->buf_size; i++) {
1416                 rc += sprintf(out_buf + rc, "%02x ",
1417                               ((unsigned char *) in_buf)[i]);
1418         }
1419         rc += sprintf(out_buf + rc, "| ");
1420         for (i = 0; i < id->buf_size; i++) {
1421                 unsigned char c = in_buf[i];
1422                 if (!isprint(c))
1423                         rc += sprintf(out_buf + rc, ".");
1424                 else
1425                         rc += sprintf(out_buf + rc, "%c", c);
1426         }
1427         rc += sprintf(out_buf + rc, "\n");
1428         return rc;
1429 }
1430
1431 /*
1432  * prints header for debug entry
1433  */
1434
1435 int
1436 debug_dflt_header_fn(debug_info_t * id, struct debug_view *view,
1437                          int area, debug_entry_t * entry, char *out_buf)
1438 {
1439         struct timespec time_spec;
1440         unsigned long long time;
1441         char *except_str;
1442         unsigned long caller;
1443         int rc = 0;
1444         unsigned int level;
1445
1446         level = entry->id.fields.level;
1447         time = entry->id.stck;
1448         /* adjust todclock to 1970 */
1449         time -= 0x8126d60e46000000LL - (0x3c26700LL * 1000000 * 4096);
1450         tod_to_timeval(time, &time_spec);
1451
1452         if (entry->id.fields.exception)
1453                 except_str = "*";
1454         else
1455                 except_str = "-";
1456         caller = ((unsigned long) entry->caller) & PSW_ADDR_INSN;
1457         rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %p  ",
1458                       area, time_spec.tv_sec, time_spec.tv_nsec / 1000, level,
1459                       except_str, entry->id.fields.cpuid, (void *) caller);
1460         return rc;
1461 }
1462
1463 /*
1464  * prints debug data sprintf-formated:
1465  * debug_sprinf_event/exception calls must be used together with this view
1466  */
1467
1468 #define DEBUG_SPRINTF_MAX_ARGS 10
1469
1470 static int
1471 debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view,
1472                         char *out_buf, debug_sprintf_entry_t *curr_event)
1473 {
1474         int num_longs, num_used_args = 0,i, rc = 0;
1475         int index[DEBUG_SPRINTF_MAX_ARGS];
1476
1477         /* count of longs fit into one entry */
1478         num_longs = id->buf_size /  sizeof(long);
1479
1480         if(num_longs < 1)
1481                 goto out; /* bufsize of entry too small */
1482         if(num_longs == 1) {
1483                 /* no args, we use only the string */
1484                 strcpy(out_buf, curr_event->string);
1485                 rc = strlen(curr_event->string);
1486                 goto out;
1487         }
1488
1489         /* number of arguments used for sprintf (without the format string) */
1490         num_used_args   = min(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1));
1491
1492         memset(index,0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int));
1493
1494         for(i = 0; i < num_used_args; i++)
1495                 index[i] = i;
1496
1497         rc =  sprintf(out_buf, curr_event->string, curr_event->args[index[0]],
1498                 curr_event->args[index[1]], curr_event->args[index[2]],
1499                 curr_event->args[index[3]], curr_event->args[index[4]],
1500                 curr_event->args[index[5]], curr_event->args[index[6]],
1501                 curr_event->args[index[7]], curr_event->args[index[8]],
1502                 curr_event->args[index[9]]);
1503
1504 out:
1505
1506         return rc;
1507 }
1508
1509 /*
1510  * clean up module
1511  */
1512 static void __exit debug_exit(void)
1513 {
1514         debugfs_remove(debug_debugfs_root_entry);
1515         unregister_sysctl_table(s390dbf_sysctl_header);
1516         return;
1517 }
1518
1519 /*
1520  * module definitions
1521  */
1522 postcore_initcall(debug_init);
1523 module_exit(debug_exit);
1524 MODULE_LICENSE("GPL");
1525
1526 EXPORT_SYMBOL(debug_register);
1527 EXPORT_SYMBOL(debug_unregister);
1528 EXPORT_SYMBOL(debug_set_level);
1529 EXPORT_SYMBOL(debug_stop_all);
1530 EXPORT_SYMBOL(debug_register_view);
1531 EXPORT_SYMBOL(debug_unregister_view);
1532 EXPORT_SYMBOL(debug_event_common);
1533 EXPORT_SYMBOL(debug_exception_common);
1534 EXPORT_SYMBOL(debug_hex_ascii_view);
1535 EXPORT_SYMBOL(debug_raw_view);
1536 EXPORT_SYMBOL(debug_dflt_header_fn);
1537 EXPORT_SYMBOL(debug_sprintf_view);
1538 EXPORT_SYMBOL(debug_sprintf_exception);
1539 EXPORT_SYMBOL(debug_sprintf_event);