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   1 /*
   2  *  arch/s390/kernel/debug.c
   3  *   S/390 debug facility
   4  *
   5  *    Copyright (C) 1999, 2000 IBM Deutschland Entwicklung GmbH,
   6  *                             IBM Corporation
   7  *    Author(s): Michael Holzheu (holzheu@de.ibm.com),
   8  *               Holger Smolinski (Holger.Smolinski@de.ibm.com)
   9  *
  10  *    Bugreports to: <Linux390@de.ibm.com>
  11  */
  12
  13 #include <linux/config.h>
  14 #include <linux/stddef.h>
  15 #include <linux/kernel.h>
  16 #include <linux/errno.h>
  17 #include <linux/slab.h>
  18 #include <linux/ctype.h>
  19 #include <linux/sysctl.h>
  20 #include <asm/uaccess.h>
  21 #include <asm/semaphore.h>
  22 #include <linux/module.h>
  23 #include <linux/init.h>
  24 #include <linux/fs.h>
  25 #include <linux/debugfs.h>
  26
  27 #include <asm/debug.h>
  28
  29 #define DEBUG_PROLOG_ENTRY -1
  30
  31 #define ALL_AREAS 0 /* copy all debug areas */
  32 #define NO_AREAS  1 /* copy no debug areas */
  33
  34 /* typedefs */
  35
  36 typedef struct file_private_info {
  37         loff_t offset;                  /* offset of last read in file */
  38         int    act_area;                /* number of last formated area */
  39         int    act_page;                /* act page in given area */
  40         int    act_entry;               /* last formated entry (offset */
  41                                         /* relative to beginning of last */
  42                                         /* formated page) */
  43         size_t act_entry_offset;        /* up to this offset we copied */
  44                                         /* in last read the last formated */
  45                                         /* entry to userland */
  46         char   temp_buf[2048];          /* buffer for output */
  47         debug_info_t *debug_info_org;   /* original debug information */
  48         debug_info_t *debug_info_snap;  /* snapshot of debug information */
  49         struct debug_view *view;        /* used view of debug info */
  50 } file_private_info_t;
  51
  52 typedef struct
  53 {
  54         char *string;
  55         /*
  56          * This assumes that all args are converted into longs
  57          * on L/390 this is the case for all types of parameter
  58          * except of floats, and long long (32 bit)
  59          *
  60          */
  61         long args[0];
  62 } debug_sprintf_entry_t;
  63
  64
  65 extern void tod_to_timeval(uint64_t todval, struct timespec *xtime);
  66
  67 /* internal function prototyes */
  68
  69 static int debug_init(void);
  70 static ssize_t debug_output(struct file *file, char __user *user_buf,
  71                         size_t user_len, loff_t * offset);
  72 static ssize_t debug_input(struct file *file, const char __user *user_buf,
  73                         size_t user_len, loff_t * offset);
  74 static int debug_open(struct inode *inode, struct file *file);
  75 static int debug_close(struct inode *inode, struct file *file);
  76 static debug_info_t*  debug_info_create(char *name, int pages_per_area,
  77                         int nr_areas, int buf_size);
  78 static void debug_info_get(debug_info_t *);
  79 static void debug_info_put(debug_info_t *);
  80 static int debug_prolog_level_fn(debug_info_t * id,
  81                         struct debug_view *view, char *out_buf);
  82 static int debug_input_level_fn(debug_info_t * id, struct debug_view *view,
  83                         struct file *file, const char __user *user_buf,
  84                         size_t user_buf_size, loff_t * offset);
  85 static int debug_prolog_pages_fn(debug_info_t * id,
  86                         struct debug_view *view, char *out_buf);
  87 static int debug_input_pages_fn(debug_info_t * id, struct debug_view *view,
  88                         struct file *file, const char __user *user_buf,
  89                         size_t user_buf_size, loff_t * offset);
  90 static int debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
  91                         struct file *file, const char __user *user_buf,
  92                         size_t user_buf_size, loff_t * offset);
  93 static int debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
  94                         char *out_buf, const char *in_buf);
  95 static int debug_raw_format_fn(debug_info_t * id,
  96                         struct debug_view *view, char *out_buf,
  97                         const char *in_buf);
  98 static int debug_raw_header_fn(debug_info_t * id, struct debug_view *view,
  99                         int area, debug_entry_t * entry, char *out_buf);
 100
 101 static int debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view,
 102                         char *out_buf, debug_sprintf_entry_t *curr_event);
 103
 104 /* globals */
 105
 106 struct debug_view debug_raw_view = {
 107         "raw",
 108         NULL,
 109         &debug_raw_header_fn,
 110         &debug_raw_format_fn,
 111         NULL,
 112         NULL
 113 };
 114
 115 struct debug_view debug_hex_ascii_view = {
 116         "hex_ascii",
 117         NULL,
 118         &debug_dflt_header_fn,
 119         &debug_hex_ascii_format_fn,
 120         NULL,
 121         NULL
 122 };
 123
 124 struct debug_view debug_level_view = {
 125         "level",
 126         &debug_prolog_level_fn,
 127         NULL,
 128         NULL,
 129         &debug_input_level_fn,
 130         NULL
 131 };
 132
 133 struct debug_view debug_pages_view = {
 134         "pages",
 135         &debug_prolog_pages_fn,
 136         NULL,
 137         NULL,
 138         &debug_input_pages_fn,
 139         NULL
 140 };
 141
 142 struct debug_view debug_flush_view = {
 143         "flush",
 144         NULL,
 145         NULL,
 146         NULL,
 147         &debug_input_flush_fn,
 148         NULL
 149 };
 150
 151 struct debug_view debug_sprintf_view = {
 152         "sprintf",
 153         NULL,
 154         &debug_dflt_header_fn,
 155         (debug_format_proc_t*)&debug_sprintf_format_fn,
 156         NULL,
 157         NULL
 158 };
 159
 160
 161 unsigned int debug_feature_version = __DEBUG_FEATURE_VERSION;
 162
 163 /* static globals */
 164
 165 static debug_info_t *debug_area_first = NULL;
 166 static debug_info_t *debug_area_last = NULL;
 167 DECLARE_MUTEX(debug_lock);
 168
 169 static int initialized;
 170
 171 static struct file_operations debug_file_ops = {
 172         .owner   = THIS_MODULE,
 173         .read    = debug_output,
 174         .write   = debug_input,
 175         .open    = debug_open,
 176         .release = debug_close,
 177 };
 178
 179 static struct dentry *debug_debugfs_root_entry;
 180
 181 /* functions */
 182
 183 /*
 184  * debug_areas_alloc
 185  * - Debug areas are implemented as a threedimensonal array:
 186  *   areas[areanumber][pagenumber][pageoffset]
 187  */
 188
 189 static debug_entry_t***
 190 debug_areas_alloc(int pages_per_area, int nr_areas)
 191 {
 192         debug_entry_t*** areas;
 193         int i,j;
 194
 195         areas = (debug_entry_t ***) kmalloc(nr_areas *
 196                                         sizeof(debug_entry_t**),
 197                                         GFP_KERNEL);
 198         if (!areas)
 199                 goto fail_malloc_areas;
 200         for (i = 0; i < nr_areas; i++) {
 201                 areas[i] = (debug_entry_t**) kmalloc(pages_per_area *
 202                                 sizeof(debug_entry_t*),GFP_KERNEL);
 203                 if (!areas[i]) {
 204                         goto fail_malloc_areas2;
 205                 }
 206                 for(j = 0; j < pages_per_area; j++) {
 207                         areas[i][j] = (debug_entry_t*)kmalloc(PAGE_SIZE,
 208                                                 GFP_KERNEL);
 209                         if(!areas[i][j]) {
 210                                 for(j--; j >=0 ; j--) {
 211                                         kfree(areas[i][j]);
 212                                 }
 213                                 kfree(areas[i]);
 214                                 goto fail_malloc_areas2;
 215                         } else {
 216                                 memset(areas[i][j],0,PAGE_SIZE);
 217                         }
 218                 }
 219         }
 220         return areas;
 221
 222 fail_malloc_areas2:
 223         for(i--; i >= 0; i--){
 224                 for(j=0; j < pages_per_area;j++){
 225                         kfree(areas[i][j]);
 226                 }
 227                 kfree(areas[i]);
 228         }
 229         kfree(areas);
 230 fail_malloc_areas:
 231         return NULL;
 232
 233 }
 234
 235
 236 /*
 237  * debug_info_alloc
 238  * - alloc new debug-info
 239  */
 240
 241 static debug_info_t*
 242 debug_info_alloc(char *name, int pages_per_area, int nr_areas, int buf_size,
 243                 int level, int mode)
 244 {
 245         debug_info_t* rc;
 246
 247         /* alloc everything */
 248
 249         rc = (debug_info_t*) kmalloc(sizeof(debug_info_t), GFP_KERNEL);
 250         if(!rc)
 251                 goto fail_malloc_rc;
 252         rc->active_entries = (int*)kmalloc(nr_areas * sizeof(int), GFP_KERNEL);
 253         if(!rc->active_entries)
 254                 goto fail_malloc_active_entries;
 255         memset(rc->active_entries, 0, nr_areas * sizeof(int));
 256         rc->active_pages = (int*)kmalloc(nr_areas * sizeof(int), GFP_KERNEL);
 257         if(!rc->active_pages)
 258                 goto fail_malloc_active_pages;
 259         memset(rc->active_pages, 0, nr_areas * sizeof(int));
 260         if((mode == ALL_AREAS) && (pages_per_area != 0)){
 261                 rc->areas = debug_areas_alloc(pages_per_area, nr_areas);
 262                 if(!rc->areas)
 263                         goto fail_malloc_areas;
 264         } else {
 265                 rc->areas = NULL;
 266         }
 267
 268         /* initialize members */
 269
 270         spin_lock_init(&rc->lock);
 271         rc->pages_per_area = pages_per_area;
 272         rc->nr_areas       = nr_areas;
 273         rc->active_area    = 0;
 274         rc->level          = level;
 275         rc->buf_size       = buf_size;
 276         rc->entry_size     = sizeof(debug_entry_t) + buf_size;
 277         strlcpy(rc->name, name, sizeof(rc->name)-1);
 278         memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *));
 279         memset(rc->debugfs_entries, 0 ,DEBUG_MAX_VIEWS *
 280                 sizeof(struct dentry*));
 281         atomic_set(&(rc->ref_count), 0);
 282
 283         return rc;
 284
 285 fail_malloc_areas:
 286         kfree(rc->active_pages);
 287 fail_malloc_active_pages:
 288         kfree(rc->active_entries);
 289 fail_malloc_active_entries:
 290         kfree(rc);
 291 fail_malloc_rc:
 292         return NULL;
 293 }
 294
 295 /*
 296  * debug_areas_free
 297  * - free all debug areas
 298  */
 299
 300 static void
 301 debug_areas_free(debug_info_t* db_info)
 302 {
 303         int i,j;
 304
 305         if(!db_info->areas)
 306                 return;
 307         for (i = 0; i < db_info->nr_areas; i++) {
 308                 for(j = 0; j < db_info->pages_per_area; j++) {
 309                         kfree(db_info->areas[i][j]);
 310                 }
 311                 kfree(db_info->areas[i]);
 312         }
 313         kfree(db_info->areas);
 314         db_info->areas = NULL;
 315 }
 316
 317 /*
 318  * debug_info_free
 319  * - free memory debug-info
 320  */
 321
 322 static void
 323 debug_info_free(debug_info_t* db_info){
 324         debug_areas_free(db_info);
 325         kfree(db_info->active_entries);
 326         kfree(db_info->active_pages);
 327         kfree(db_info);
 328 }
 329
 330 /*
 331  * debug_info_create
 332  * - create new debug-info
 333  */
 334
 335 static debug_info_t*
 336 debug_info_create(char *name, int pages_per_area, int nr_areas, int buf_size)
 337 {
 338         debug_info_t* rc;
 339
 340         rc = debug_info_alloc(name, pages_per_area, nr_areas, buf_size,
 341                                 DEBUG_DEFAULT_LEVEL, ALL_AREAS);
 342         if(!rc)
 343                 goto out;
 344
 345         /* create root directory */
 346         rc->debugfs_root_entry = debugfs_create_dir(rc->name,
 347                                         debug_debugfs_root_entry);
 348
 349         /* append new element to linked list */
 350         if (!debug_area_first) {
 351                 /* first element in list */
 352                 debug_area_first = rc;
 353                 rc->prev = NULL;
 354         } else {
 355                 /* append element to end of list */
 356                 debug_area_last->next = rc;
 357                 rc->prev = debug_area_last;
 358         }
 359         debug_area_last = rc;
 360         rc->next = NULL;
 361
 362         debug_info_get(rc);
 363 out:
 364         return rc;
 365 }
 366
 367 /*
 368  * debug_info_copy
 369  * - copy debug-info
 370  */
 371
 372 static debug_info_t*
 373 debug_info_copy(debug_info_t* in, int mode)
 374 {
 375         int i,j;
 376         debug_info_t* rc;
 377         unsigned long flags;
 378
 379         /* get a consistent copy of the debug areas */
 380         do {
 381                 rc = debug_info_alloc(in->name, in->pages_per_area,
 382                         in->nr_areas, in->buf_size, in->level, mode);
 383                 spin_lock_irqsave(&in->lock, flags);
 384                 if(!rc)
 385                         goto out;
 386                 /* has something changed in the meantime ? */
 387                 if((rc->pages_per_area == in->pages_per_area) &&
 388                    (rc->nr_areas == in->nr_areas)) {
 389                         break;
 390                 }
 391                 spin_unlock_irqrestore(&in->lock, flags);
 392                 debug_info_free(rc);
 393         } while (1);
 394
 395         if(!rc || (mode == NO_AREAS))
 396                 goto out;
 397
 398         for(i = 0; i < in->nr_areas; i++){
 399                 for(j = 0; j < in->pages_per_area; j++) {
 400                         memcpy(rc->areas[i][j], in->areas[i][j],PAGE_SIZE);
 401                 }
 402         }
 403 out:
 404         spin_unlock_irqrestore(&in->lock, flags);
 405         return rc;
 406 }
 407
 408 /*
 409  * debug_info_get
 410  * - increments reference count for debug-info
 411  */
 412
 413 static void
 414 debug_info_get(debug_info_t * db_info)
 415 {
 416         if (db_info)
 417                 atomic_inc(&db_info->ref_count);
 418 }
 419
 420 /*
 421  * debug_info_put:
 422  * - decreases reference count for debug-info and frees it if necessary
 423  */
 424
 425 static void
 426 debug_info_put(debug_info_t *db_info)
 427 {
 428         int i;
 429
 430         if (!db_info)
 431                 return;
 432         if (atomic_dec_and_test(&db_info->ref_count)) {
 433                 for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
 434                         if (!db_info->views[i])
 435                                 continue;
 436                         debugfs_remove(db_info->debugfs_entries[i]);
 437                 }
 438                 debugfs_remove(db_info->debugfs_root_entry);
 439                 if(db_info == debug_area_first)
 440                         debug_area_first = db_info->next;
 441                 if(db_info == debug_area_last)
 442                         debug_area_last = db_info->prev;
 443                 if(db_info->prev) db_info->prev->next = db_info->next;
 444                 if(db_info->next) db_info->next->prev = db_info->prev;
 445                 debug_info_free(db_info);
 446         }
 447 }
 448
 449 /*
 450  * debug_format_entry:
 451  * - format one debug entry and return size of formated data
 452  */
 453
 454 static int
 455 debug_format_entry(file_private_info_t *p_info)
 456 {
 457         debug_info_t *id_snap   = p_info->debug_info_snap;
 458         struct debug_view *view = p_info->view;
 459         debug_entry_t *act_entry;
 460         size_t len = 0;
 461         if(p_info->act_entry == DEBUG_PROLOG_ENTRY){
 462                 /* print prolog */
 463                 if (view->prolog_proc)
 464                         len += view->prolog_proc(id_snap,view,p_info->temp_buf);
 465                 goto out;
 466         }
 467         if (!id_snap->areas) /* this is true, if we have a prolog only view */
 468                 goto out;    /* or if 'pages_per_area' is 0 */
 469         act_entry = (debug_entry_t *) ((char*)id_snap->areas[p_info->act_area]
 470                                 [p_info->act_page] + p_info->act_entry);
 471
 472         if (act_entry->id.stck == 0LL)
 473                         goto out;  /* empty entry */
 474         if (view->header_proc)
 475                 len += view->header_proc(id_snap, view, p_info->act_area,
 476                                         act_entry, p_info->temp_buf + len);
 477         if (view->format_proc)
 478                 len += view->format_proc(id_snap, view, p_info->temp_buf + len,
 479                                                 DEBUG_DATA(act_entry));
 480 out:
 481         return len;
 482 }
 483
 484 /*
 485  * debug_next_entry:
 486  * - goto next entry in p_info
 487  */
 488
 489 extern inline int
 490 debug_next_entry(file_private_info_t *p_info)
 491 {
 492         debug_info_t *id;
 493
 494         id = p_info->debug_info_snap;
 495         if(p_info->act_entry == DEBUG_PROLOG_ENTRY){
 496                 p_info->act_entry = 0;
 497                 p_info->act_page  = 0;
 498                 goto out;
 499         }
 500         if(!id->areas)
 501                 return 1;
 502         p_info->act_entry += id->entry_size;
 503         /* switch to next page, if we reached the end of the page  */
 504         if (p_info->act_entry > (PAGE_SIZE - id->entry_size)){
 505                 /* next page */
 506                 p_info->act_entry = 0;
 507                 p_info->act_page += 1;
 508                 if((p_info->act_page % id->pages_per_area) == 0) {
 509                         /* next area */
 510                         p_info->act_area++;
 511                         p_info->act_page=0;
 512                 }
 513                 if(p_info->act_area >= id->nr_areas)
 514                         return 1;
 515         }
 516 out:
 517         return 0;
 518 }
 519
 520 /*
 521  * debug_output:
 522  * - called for user read()
 523  * - copies formated debug entries to the user buffer
 524  */
 525
 526 static ssize_t
 527 debug_output(struct file *file,         /* file descriptor */
 528             char __user *user_buf,      /* user buffer */
 529             size_t  len,                /* length of buffer */
 530             loff_t *offset)             /* offset in the file */
 531 {
 532         size_t count = 0;
 533         size_t entry_offset;
 534         file_private_info_t *p_info;
 535
 536         p_info = ((file_private_info_t *) file->private_data);
 537         if (*offset != p_info->offset)
 538                 return -EPIPE;
 539         if(p_info->act_area >= p_info->debug_info_snap->nr_areas)
 540                 return 0;
 541         entry_offset = p_info->act_entry_offset;
 542         while(count < len){
 543                 int formatted_line_size;
 544                 int formatted_line_residue;
 545                 int user_buf_residue;
 546                 size_t copy_size;
 547
 548                 formatted_line_size = debug_format_entry(p_info);
 549                 formatted_line_residue = formatted_line_size - entry_offset;
 550                 user_buf_residue = len-count;
 551                 copy_size = min(user_buf_residue, formatted_line_residue);
 552                 if(copy_size){
 553                         if (copy_to_user(user_buf + count, p_info->temp_buf
 554                                         + entry_offset, copy_size))
 555                                 return -EFAULT;
 556                         count += copy_size;
 557                         entry_offset += copy_size;
 558                 }
 559                 if(copy_size == formatted_line_residue){
 560                         entry_offset = 0;
 561                         if(debug_next_entry(p_info))
 562                                 goto out;
 563                 }
 564         }
 565 out:
 566         p_info->offset           = *offset + count;
 567         p_info->act_entry_offset = entry_offset;
 568         *offset = p_info->offset;
 569         return count;
 570 }
 571
 572 /*
 573  * debug_input:
 574  * - called for user write()
 575  * - calls input function of view
 576  */
 577
 578 static ssize_t
 579 debug_input(struct file *file, const char __user *user_buf, size_t length,
 580                 loff_t *offset)
 581 {
 582         int rc = 0;
 583         file_private_info_t *p_info;
 584
 585         down(&debug_lock);
 586         p_info = ((file_private_info_t *) file->private_data);
 587         if (p_info->view->input_proc)
 588                 rc = p_info->view->input_proc(p_info->debug_info_org,
 589                                               p_info->view, file, user_buf,
 590                                               length, offset);
 591         else
 592                 rc = -EPERM;
 593         up(&debug_lock);
 594         return rc;              /* number of input characters */
 595 }
 596
 597 /*
 598  * debug_open:
 599  * - called for user open()
 600  * - copies formated output to private_data area of the file
 601  *   handle
 602  */
 603
 604 static int
 605 debug_open(struct inode *inode, struct file *file)
 606 {
 607         int i = 0, rc = 0;
 608         file_private_info_t *p_info;
 609         debug_info_t *debug_info, *debug_info_snapshot;
 610
 611         down(&debug_lock);
 612         debug_info = (struct debug_info*)file->f_dentry->d_inode->u.generic_ip;
 613         /* find debug view */
 614         for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
 615                 if (!debug_info->views[i])
 616                         continue;
 617                 else if (debug_info->debugfs_entries[i] ==
 618                          file->f_dentry) {
 619                         goto found;     /* found view ! */
 620                 }
 621         }
 622         /* no entry found */
 623         rc = -EINVAL;
 624         goto out;
 625
 626 found:
 627
 628         /* Make snapshot of current debug areas to get it consistent.     */
 629         /* To copy all the areas is only needed, if we have a view which  */
 630         /* formats the debug areas. */
 631
 632         if(!debug_info->views[i]->format_proc &&
 633                 !debug_info->views[i]->header_proc){
 634                 debug_info_snapshot = debug_info_copy(debug_info, NO_AREAS);
 635         } else {
 636                 debug_info_snapshot = debug_info_copy(debug_info, ALL_AREAS);
 637         }
 638
 639         if(!debug_info_snapshot){
 640                 rc = -ENOMEM;
 641                 goto out;
 642         }
 643         p_info = (file_private_info_t *) kmalloc(sizeof(file_private_info_t),
 644                                                 GFP_KERNEL);
 645         if(!p_info){
 646                 if(debug_info_snapshot)
 647                         debug_info_free(debug_info_snapshot);
 648                 rc = -ENOMEM;
 649                 goto out;
 650         }
 651         p_info->offset = 0;
 652         p_info->debug_info_snap = debug_info_snapshot;
 653         p_info->debug_info_org  = debug_info;
 654         p_info->view = debug_info->views[i];
 655         p_info->act_area = 0;
 656         p_info->act_page = 0;
 657         p_info->act_entry = DEBUG_PROLOG_ENTRY;
 658         p_info->act_entry_offset = 0;
 659         file->private_data = p_info;
 660         debug_info_get(debug_info);
 661 out:
 662         up(&debug_lock);
 663         return rc;
 664 }
 665
 666 /*
 667  * debug_close:
 668  * - called for user close()
 669  * - deletes  private_data area of the file handle
 670  */
 671
 672 static int
 673 debug_close(struct inode *inode, struct file *file)
 674 {
 675         file_private_info_t *p_info;
 676         p_info = (file_private_info_t *) file->private_data;
 677         if(p_info->debug_info_snap)
 678                 debug_info_free(p_info->debug_info_snap);
 679         debug_info_put(p_info->debug_info_org);
 680         kfree(file->private_data);
 681         return 0;               /* success */
 682 }
 683
 684 /*
 685  * debug_register:
 686  * - creates and initializes debug area for the caller
 687  * - returns handle for debug area
 688  */
 689
 690 debug_info_t*
 691 debug_register (char *name, int pages_per_area, int nr_areas, int buf_size)
 692 {
 693         debug_info_t *rc = NULL;
 694
 695         if (!initialized)
 696                 BUG();
 697         down(&debug_lock);
 698
 699         /* create new debug_info */
 700
 701         rc = debug_info_create(name, pages_per_area, nr_areas, buf_size);
 702         if(!rc)
 703                 goto out;
 704         debug_register_view(rc, &debug_level_view);
 705         debug_register_view(rc, &debug_flush_view);
 706         debug_register_view(rc, &debug_pages_view);
 707 out:
 708         if (!rc){
 709                 printk(KERN_ERR "debug: debug_register failed for %s\n",name);
 710         }
 711         up(&debug_lock);
 712         return rc;
 713 }
 714
 715 /*
 716  * debug_unregister:
 717  * - give back debug area
 718  */
 719
 720 void
 721 debug_unregister(debug_info_t * id)
 722 {
 723         if (!id)
 724                 goto out;
 725         down(&debug_lock);
 726         debug_info_put(id);
 727         up(&debug_lock);
 728
 729 out:
 730         return;
 731 }
 732
 733 /*
 734  * debug_set_size:
 735  * - set area size (number of pages) and number of areas
 736  */
 737 static int
 738 debug_set_size(debug_info_t* id, int nr_areas, int pages_per_area)
 739 {
 740         unsigned long flags;
 741         debug_entry_t *** new_areas;
 742         int rc=0;
 743
 744         if(!id || (nr_areas <= 0) || (pages_per_area < 0))
 745                 return -EINVAL;
 746         if(pages_per_area > 0){
 747                 new_areas = debug_areas_alloc(pages_per_area, nr_areas);
 748                 if(!new_areas) {
 749                         printk(KERN_WARNING "debug: could not allocate memory "\
 750                                          "for pagenumber: %i\n",pages_per_area);
 751                         rc = -ENOMEM;
 752                         goto out;
 753                 }
 754         } else {
 755                 new_areas = NULL;
 756         }
 757         spin_lock_irqsave(&id->lock,flags);
 758         debug_areas_free(id);
 759         id->areas = new_areas;
 760         id->nr_areas = nr_areas;
 761         id->pages_per_area = pages_per_area;
 762         id->active_area = 0;
 763         memset(id->active_entries,0,sizeof(int)*id->nr_areas);
 764         memset(id->active_pages, 0, sizeof(int)*id->nr_areas);
 765         spin_unlock_irqrestore(&id->lock,flags);
 766         printk(KERN_INFO "debug: %s: set new size (%i pages)\n"\
 767                          ,id->name, pages_per_area);
 768 out:
 769         return rc;
 770 }
 771
 772 /*
 773  * debug_set_level:
 774  * - set actual debug level
 775  */
 776
 777 void
 778 debug_set_level(debug_info_t* id, int new_level)
 779 {
 780         unsigned long flags;
 781         if(!id)
 782                 return;
 783         spin_lock_irqsave(&id->lock,flags);
 784         if(new_level == DEBUG_OFF_LEVEL){
 785                 id->level = DEBUG_OFF_LEVEL;
 786                 printk(KERN_INFO "debug: %s: switched off\n",id->name);
 787         } else if ((new_level > DEBUG_MAX_LEVEL) || (new_level < 0)) {
 788                 printk(KERN_INFO
 789                         "debug: %s: level %i is out of range (%i - %i)\n",
 790                         id->name, new_level, 0, DEBUG_MAX_LEVEL);
 791         } else {
 792                 id->level = new_level;
 793         }
 794         spin_unlock_irqrestore(&id->lock,flags);
 795 }
 796
 797
 798 /*
 799  * proceed_active_entry:
 800  * - set active entry to next in the ring buffer
 801  */
 802
 803 extern inline void
 804 proceed_active_entry(debug_info_t * id)
 805 {
 806         if ((id->active_entries[id->active_area] += id->entry_size)
 807             > (PAGE_SIZE - id->entry_size)){
 808                 id->active_entries[id->active_area] = 0;
 809                 id->active_pages[id->active_area] =
 810                         (id->active_pages[id->active_area] + 1) %
 811                         id->pages_per_area;
 812         }
 813 }
 814
 815 /*
 816  * proceed_active_area:
 817  * - set active area to next in the ring buffer
 818  */
 819
 820 extern inline void
 821 proceed_active_area(debug_info_t * id)
 822 {
 823         id->active_area++;
 824         id->active_area = id->active_area % id->nr_areas;
 825 }
 826
 827 /*
 828  * get_active_entry:
 829  */
 830
 831 extern inline debug_entry_t*
 832 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 extern inline void
 845 debug_finish_entry(debug_info_t * id, debug_entry_t* active, int level,
 846                         int exception)
 847 {
 848         active->id.stck = get_clock();
 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 5677
 862 #define CTL_S390DBF_STOPPABLE 5678
 863 #define CTL_S390DBF_ACTIVE 5679
 864
 865 /*
 866  * proc handler for the running debug_active sysctl
 867  * always allow read, allow write only if debug_stoppable is set or
 868  * if debug_active is already off
 869  */
 870 static int
 871 s390dbf_procactive(ctl_table *table, int write, struct file *filp,
 872                      void __user *buffer, size_t *lenp, loff_t *ppos)
 873 {
 874         if (!write || debug_stoppable || !debug_active)
 875                 return proc_dointvec(table, write, filp, buffer, lenp, ppos);
 876         else
 877                 return 0;
 878 }
 879
 880
 881 static struct ctl_table s390dbf_table[] = {
 882         {
 883                 .ctl_name       = CTL_S390DBF_STOPPABLE,
 884                 .procname       = "debug_stoppable",
 885                 .data           = &debug_stoppable,
 886                 .maxlen         = sizeof(int),
 887                 .mode           = S_IRUGO | S_IWUSR,
 888                 .proc_handler   = &proc_dointvec,
 889                 .strategy       = &sysctl_intvec,
 890         },
 891          {
 892                 .ctl_name       = CTL_S390DBF_ACTIVE,
 893                 .procname       = "debug_active",
 894                 .data           = &debug_active,
 895                 .maxlen         = sizeof(int),
 896                 .mode           = S_IRUGO | S_IWUSR,
 897                 .proc_handler   = &s390dbf_procactive,
 898                 .strategy       = &sysctl_intvec,
 899         },
 900         { .ctl_name = 0 }
 901 };
 902
 903 static struct ctl_table s390dbf_dir_table[] = {
 904         {
 905                 .ctl_name       = CTL_S390DBF,
 906                 .procname       = "s390dbf",
 907                 .maxlen         = 0,
 908                 .mode           = S_IRUGO | S_IXUGO,
 909                 .child          = s390dbf_table,
 910         },
 911         { .ctl_name = 0 }
 912 };
 913
 914 struct ctl_table_header *s390dbf_sysctl_header;
 915
 916 void
 917 debug_stop_all(void)
 918 {
 919         if (debug_stoppable)
 920                 debug_active = 0;
 921 }
 922
 923
 924 /*
 925  * debug_event_common:
 926  * - write debug entry with given size
 927  */
 928
 929 debug_entry_t*
 930 debug_event_common(debug_info_t * id, int level, const void *buf, int len)
 931 {
 932         unsigned long flags;
 933         debug_entry_t *active;
 934
 935         if (!debug_active || !id->areas)
 936                 return NULL;
 937         spin_lock_irqsave(&id->lock, flags);
 938         active = get_active_entry(id);
 939         memset(DEBUG_DATA(active), 0, id->buf_size);
 940         memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
 941         debug_finish_entry(id, active, level, 0);
 942         spin_unlock_irqrestore(&id->lock, flags);
 943
 944         return active;
 945 }
 946
 947 /*
 948  * debug_exception_common:
 949  * - write debug entry with given size and switch to next debug area
 950  */
 951
 952 debug_entry_t
 953 *debug_exception_common(debug_info_t * id, int level, const void *buf, int len)
 954 {
 955         unsigned long flags;
 956         debug_entry_t *active;
 957
 958         if (!debug_active || !id->areas)
 959                 return NULL;
 960         spin_lock_irqsave(&id->lock, flags);
 961         active = get_active_entry(id);
 962         memset(DEBUG_DATA(active), 0, id->buf_size);
 963         memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
 964         debug_finish_entry(id, active, level, 1);
 965         spin_unlock_irqrestore(&id->lock, flags);
 966
 967         return active;
 968 }
 969
 970 /*
 971  * counts arguments in format string for sprintf view
 972  */
 973
 974 extern inline int
 975 debug_count_numargs(char *string)
 976 {
 977         int numargs=0;
 978
 979         while(*string) {
 980                 if(*string++=='%')
 981                         numargs++;
 982         }
 983         return(numargs);
 984 }
 985
 986 /*
 987  * debug_sprintf_event:
 988  */
 989
 990 debug_entry_t*
 991 debug_sprintf_event(debug_info_t* id, int level,char *string,...)
 992 {
 993         va_list   ap;
 994         int numargs,idx;
 995         unsigned long flags;
 996         debug_sprintf_entry_t *curr_event;
 997         debug_entry_t *active;
 998
 999         if((!id) || (level > id->level))
1000                 return NULL;
1001         if (!debug_active || !id->areas)
1002                 return NULL;
1003         numargs=debug_count_numargs(string);
1004
1005         spin_lock_irqsave(&id->lock, flags);
1006         active = get_active_entry(id);
1007         curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active);
1008         va_start(ap,string);
1009         curr_event->string=string;
1010         for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
1011                 curr_event->args[idx]=va_arg(ap,long);
1012         va_end(ap);
1013         debug_finish_entry(id, active, level, 0);
1014         spin_unlock_irqrestore(&id->lock, flags);
1015
1016         return active;
1017 }
1018
1019 /*
1020  * debug_sprintf_exception:
1021  */
1022
1023 debug_entry_t*
1024 debug_sprintf_exception(debug_info_t* id, int level,char *string,...)
1025 {
1026         va_list   ap;
1027         int numargs,idx;
1028         unsigned long flags;
1029         debug_sprintf_entry_t *curr_event;
1030         debug_entry_t *active;
1031
1032         if((!id) || (level > id->level))
1033                 return NULL;
1034         if (!debug_active || !id->areas)
1035                 return NULL;
1036
1037         numargs=debug_count_numargs(string);
1038
1039         spin_lock_irqsave(&id->lock, flags);
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, 1);
1048         spin_unlock_irqrestore(&id->lock, flags);
1049
1050         return active;
1051 }
1052
1053 /*
1054  * debug_init:
1055  * - is called exactly once to initialize the debug feature
1056  */
1057
1058 static int
1059 __init debug_init(void)
1060 {
1061         int rc = 0;
1062
1063         s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table, 1);
1064         down(&debug_lock);
1065         debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT,NULL);
1066         printk(KERN_INFO "debug: Initialization complete\n");
1067         initialized = 1;
1068         up(&debug_lock);
1069
1070         return rc;
1071 }
1072
1073 /*
1074  * debug_register_view:
1075  */
1076
1077 int
1078 debug_register_view(debug_info_t * id, struct debug_view *view)
1079 {
1080         int rc = 0;
1081         int i;
1082         unsigned long flags;
1083         mode_t mode = S_IFREG;
1084         struct dentry *pde;
1085
1086         if (!id)
1087                 goto out;
1088         if (view->prolog_proc || view->format_proc || view->header_proc)
1089                 mode |= S_IRUSR;
1090         if (view->input_proc)
1091                 mode |= S_IWUSR;
1092         pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry,
1093                                 id , &debug_file_ops);
1094         if (!pde){
1095                 printk(KERN_WARNING "debug: debugfs_create_file() failed!"\
1096                         " Cannot register view %s/%s\n", id->name,view->name);
1097                 rc = -1;
1098                 goto out;
1099         }
1100         spin_lock_irqsave(&id->lock, flags);
1101         for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1102                 if (!id->views[i])
1103                         break;
1104         }
1105         if (i == DEBUG_MAX_VIEWS) {
1106                 printk(KERN_WARNING "debug: cannot register view %s/%s\n",
1107                         id->name,view->name);
1108                 printk(KERN_WARNING
1109                         "debug: maximum number of views reached (%i)!\n", i);
1110                 debugfs_remove(pde);
1111                 rc = -1;
1112         } else {
1113                 id->views[i] = view;
1114                 id->debugfs_entries[i] = pde;
1115         }
1116         spin_unlock_irqrestore(&id->lock, flags);
1117 out:
1118         return rc;
1119 }
1120
1121 /*
1122  * debug_unregister_view:
1123  */
1124
1125 int
1126 debug_unregister_view(debug_info_t * id, struct debug_view *view)
1127 {
1128         int rc = 0;
1129         int i;
1130         unsigned long flags;
1131
1132         if (!id)
1133                 goto out;
1134         spin_lock_irqsave(&id->lock, flags);
1135         for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1136                 if (id->views[i] == view)
1137                         break;
1138         }
1139         if (i == DEBUG_MAX_VIEWS)
1140                 rc = -1;
1141         else {
1142                 debugfs_remove(id->debugfs_entries[i]);
1143                 id->views[i] = NULL;
1144                 rc = 0;
1145         }
1146         spin_unlock_irqrestore(&id->lock, flags);
1147 out:
1148         return rc;
1149 }
1150
1151 static inline char *
1152 debug_get_user_string(const char __user *user_buf, size_t user_len)
1153 {
1154         char* buffer;
1155
1156         buffer = kmalloc(user_len + 1, GFP_KERNEL);
1157         if (!buffer)
1158                 return ERR_PTR(-ENOMEM);
1159         if (copy_from_user(buffer, user_buf, user_len) != 0) {
1160                 kfree(buffer);
1161                 return ERR_PTR(-EFAULT);
1162         }
1163         /* got the string, now strip linefeed. */
1164         if (buffer[user_len - 1] == '\n')
1165                 buffer[user_len - 1] = 0;
1166         else
1167                 buffer[user_len] = 0;
1168         return buffer;
1169 }
1170
1171 static inline int
1172 debug_get_uint(char *buf)
1173 {
1174         int rc;
1175
1176         for(; isspace(*buf); buf++);
1177         rc = simple_strtoul(buf, &buf, 10);
1178         if(*buf){
1179                 printk("debug: no integer specified!\n");
1180                 rc = -EINVAL;
1181         }
1182         return rc;
1183 }
1184
1185 /*
1186  * functions for debug-views
1187  ***********************************
1188 */
1189
1190 /*
1191  * prints out actual debug level
1192  */
1193
1194 static int
1195 debug_prolog_pages_fn(debug_info_t * id,
1196                                  struct debug_view *view, char *out_buf)
1197 {
1198         return sprintf(out_buf, "%i\n", id->pages_per_area);
1199 }
1200
1201 /*
1202  * reads new size (number of pages per debug area)
1203  */
1204
1205 static int
1206 debug_input_pages_fn(debug_info_t * id, struct debug_view *view,
1207                         struct file *file, const char __user *user_buf,
1208                         size_t user_len, loff_t * offset)
1209 {
1210         char *str;
1211         int rc,new_pages;
1212
1213         if (user_len > 0x10000)
1214                 user_len = 0x10000;
1215         if (*offset != 0){
1216                 rc = -EPIPE;
1217                 goto out;
1218         }
1219         str = debug_get_user_string(user_buf,user_len);
1220         if(IS_ERR(str)){
1221                 rc = PTR_ERR(str);
1222                 goto out;
1223         }
1224         new_pages = debug_get_uint(str);
1225         if(new_pages < 0){
1226                 rc = -EINVAL;
1227                 goto free_str;
1228         }
1229         rc = debug_set_size(id,id->nr_areas, new_pages);
1230         if(rc != 0){
1231                 rc = -EINVAL;
1232                 goto free_str;
1233         }
1234         rc = user_len;
1235 free_str:
1236         kfree(str);
1237 out:
1238         *offset += user_len;
1239         return rc;              /* number of input characters */
1240 }
1241
1242 /*
1243  * prints out actual debug level
1244  */
1245
1246 static int
1247 debug_prolog_level_fn(debug_info_t * id, struct debug_view *view, char *out_buf)
1248 {
1249         int rc = 0;
1250
1251         if(id->level == DEBUG_OFF_LEVEL) {
1252                 rc = sprintf(out_buf,"-\n");
1253         }
1254         else {
1255                 rc = sprintf(out_buf, "%i\n", id->level);
1256         }
1257         return rc;
1258 }
1259
1260 /*
1261  * reads new debug level
1262  */
1263
1264 static int
1265 debug_input_level_fn(debug_info_t * id, struct debug_view *view,
1266                         struct file *file, const char __user *user_buf,
1267                         size_t user_len, loff_t * offset)
1268 {
1269         char *str;
1270         int rc,new_level;
1271
1272         if (user_len > 0x10000)
1273                 user_len = 0x10000;
1274         if (*offset != 0){
1275                 rc = -EPIPE;
1276                 goto out;
1277         }
1278         str = debug_get_user_string(user_buf,user_len);
1279         if(IS_ERR(str)){
1280                 rc = PTR_ERR(str);
1281                 goto out;
1282         }
1283         if(str[0] == '-'){
1284                 debug_set_level(id, DEBUG_OFF_LEVEL);
1285                 rc = user_len;
1286                 goto free_str;
1287         } else {
1288                 new_level = debug_get_uint(str);
1289         }
1290         if(new_level < 0) {
1291                 printk(KERN_INFO "debug: level `%s` is not valid\n", str);
1292                 rc = -EINVAL;
1293         } else {
1294                 debug_set_level(id, new_level);
1295                 rc = user_len;
1296         }
1297 free_str:
1298         kfree(str);
1299 out:
1300         *offset += user_len;
1301         return rc;              /* number of input characters */
1302 }
1303
1304
1305 /*
1306  * flushes debug areas
1307  */
1308
1309 void
1310 debug_flush(debug_info_t* id, int area)
1311 {
1312         unsigned long flags;
1313         int i,j;
1314
1315         if(!id || !id->areas)
1316                 return;
1317         spin_lock_irqsave(&id->lock,flags);
1318         if(area == DEBUG_FLUSH_ALL){
1319                 id->active_area = 0;
1320                 memset(id->active_entries, 0, id->nr_areas * sizeof(int));
1321                 for (i = 0; i < id->nr_areas; i++) {
1322                         id->active_pages[i] = 0;
1323                         for(j = 0; j < id->pages_per_area; j++) {
1324                                 memset(id->areas[i][j], 0, PAGE_SIZE);
1325                         }
1326                 }
1327                 printk(KERN_INFO "debug: %s: all areas flushed\n",id->name);
1328         } else if(area >= 0 && area < id->nr_areas) {
1329                 id->active_entries[area] = 0;
1330                 id->active_pages[area] = 0;
1331                 for(i = 0; i < id->pages_per_area; i++) {
1332                         memset(id->areas[area][i],0,PAGE_SIZE);
1333                 }
1334                 printk(KERN_INFO "debug: %s: area %i has been flushed\n",
1335                         id->name, area);
1336         } else {
1337                 printk(KERN_INFO
1338                       "debug: %s: area %i cannot be flushed (range: %i - %i)\n",
1339                         id->name, area, 0, id->nr_areas-1);
1340         }
1341         spin_unlock_irqrestore(&id->lock,flags);
1342 }
1343
1344 /*
1345  * view function: flushes debug areas
1346  */
1347
1348 static int
1349 debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
1350                         struct file *file, const char __user *user_buf,
1351                         size_t user_len, loff_t * offset)
1352 {
1353         char input_buf[1];
1354         int rc = user_len;
1355
1356         if (user_len > 0x10000)
1357                 user_len = 0x10000;
1358         if (*offset != 0){
1359                 rc = -EPIPE;
1360                 goto out;
1361         }
1362         if (copy_from_user(input_buf, user_buf, 1)){
1363                 rc = -EFAULT;
1364                 goto out;
1365         }
1366         if(input_buf[0] == '-') {
1367                 debug_flush(id, DEBUG_FLUSH_ALL);
1368                 goto out;
1369         }
1370         if (isdigit(input_buf[0])) {
1371                 int area = ((int) input_buf[0] - (int) '0');
1372                 debug_flush(id, area);
1373                 goto out;
1374         }
1375
1376         printk(KERN_INFO "debug: area `%c` is not valid\n", input_buf[0]);
1377
1378 out:
1379         *offset += user_len;
1380         return rc;              /* number of input characters */
1381 }
1382
1383 /*
1384  * prints debug header in raw format
1385  */
1386
1387 static int
1388 debug_raw_header_fn(debug_info_t * id, struct debug_view *view,
1389                         int area, debug_entry_t * entry, char *out_buf)
1390 {
1391         int rc;
1392
1393         rc = sizeof(debug_entry_t);
1394         memcpy(out_buf,entry,sizeof(debug_entry_t));
1395         return rc;
1396 }
1397
1398 /*
1399  * prints debug data in raw format
1400  */
1401
1402 static int
1403 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
1417 static int
1418 debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
1419                           char *out_buf, const char *in_buf)
1420 {
1421         int i, rc = 0;
1422
1423         for (i = 0; i < id->buf_size; i++) {
1424                 rc += sprintf(out_buf + rc, "%02x ",
1425                               ((unsigned char *) in_buf)[i]);
1426         }
1427         rc += sprintf(out_buf + rc, "| ");
1428         for (i = 0; i < id->buf_size; i++) {
1429                 unsigned char c = in_buf[i];
1430                 if (!isprint(c))
1431                         rc += sprintf(out_buf + rc, ".");
1432                 else
1433                         rc += sprintf(out_buf + rc, "%c", c);
1434         }
1435         rc += sprintf(out_buf + rc, "\n");
1436         return rc;
1437 }
1438
1439 /*
1440  * prints header for debug entry
1441  */
1442
1443 int
1444 debug_dflt_header_fn(debug_info_t * id, struct debug_view *view,
1445                          int area, debug_entry_t * entry, char *out_buf)
1446 {
1447         struct timespec time_spec;
1448         unsigned long long time;
1449         char *except_str;
1450         unsigned long caller;
1451         int rc = 0;
1452         unsigned int level;
1453
1454         level = entry->id.fields.level;
1455         time = entry->id.stck;
1456         /* adjust todclock to 1970 */
1457         time -= 0x8126d60e46000000LL - (0x3c26700LL * 1000000 * 4096);
1458         tod_to_timeval(time, &time_spec);
1459
1460         if (entry->id.fields.exception)
1461                 except_str = "*";
1462         else
1463                 except_str = "-";
1464         caller = ((unsigned long) entry->caller) & PSW_ADDR_INSN;
1465         rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %p  ",
1466                       area, time_spec.tv_sec, time_spec.tv_nsec / 1000, level,
1467                       except_str, entry->id.fields.cpuid, (void *) caller);
1468         return rc;
1469 }
1470
1471 /*
1472  * prints debug data sprintf-formated:
1473  * debug_sprinf_event/exception calls must be used together with this view
1474  */
1475
1476 #define DEBUG_SPRINTF_MAX_ARGS 10
1477
1478 static int
1479 debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view,
1480                         char *out_buf, debug_sprintf_entry_t *curr_event)
1481 {
1482         int num_longs, num_used_args = 0,i, rc = 0;
1483         int index[DEBUG_SPRINTF_MAX_ARGS];
1484
1485         /* count of longs fit into one entry */
1486         num_longs = id->buf_size /  sizeof(long);
1487
1488         if(num_longs < 1)
1489                 goto out; /* bufsize of entry too small */
1490         if(num_longs == 1) {
1491                 /* no args, we use only the string */
1492                 strcpy(out_buf, curr_event->string);
1493                 rc = strlen(curr_event->string);
1494                 goto out;
1495         }
1496
1497         /* number of arguments used for sprintf (without the format string) */
1498         num_used_args   = min(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1));
1499
1500         memset(index,0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int));
1501
1502         for(i = 0; i < num_used_args; i++)
1503                 index[i] = i;
1504
1505         rc =  sprintf(out_buf, curr_event->string, curr_event->args[index[0]],
1506                 curr_event->args[index[1]], curr_event->args[index[2]],
1507                 curr_event->args[index[3]], curr_event->args[index[4]],
1508                 curr_event->args[index[5]], curr_event->args[index[6]],
1509                 curr_event->args[index[7]], curr_event->args[index[8]],
1510                 curr_event->args[index[9]]);
1511
1512 out:
1513
1514         return rc;
1515 }
1516
1517 /*
1518  * clean up module
1519  */
1520 void
1521 __exit debug_exit(void)
1522 {
1523         debugfs_remove(debug_debugfs_root_entry);
1524         unregister_sysctl_table(s390dbf_sysctl_header);
1525         return;
1526 }
1527
1528 /*
1529  * module definitions
1530  */
1531 postcore_initcall(debug_init);
1532 module_exit(debug_exit);
1533 MODULE_LICENSE("GPL");
1534
1535 EXPORT_SYMBOL(debug_register);
1536 EXPORT_SYMBOL(debug_unregister);
1537 EXPORT_SYMBOL(debug_set_level);
1538 EXPORT_SYMBOL(debug_stop_all);
1539 EXPORT_SYMBOL(debug_register_view);
1540 EXPORT_SYMBOL(debug_unregister_view);
1541 EXPORT_SYMBOL(debug_event_common);
1542 EXPORT_SYMBOL(debug_exception_common);
1543 EXPORT_SYMBOL(debug_hex_ascii_view);
1544 EXPORT_SYMBOL(debug_raw_view);
1545 EXPORT_SYMBOL(debug_dflt_header_fn);
1546 EXPORT_SYMBOL(debug_sprintf_view);
1547 EXPORT_SYMBOL(debug_sprintf_exception);
1548 EXPORT_SYMBOL(debug_sprintf_event);