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 <linux/module.h>
  21 #include <linux/init.h>
  22 #include <linux/fs.h>
  23 #include <linux/debugfs.h>
  24
  25 #include <asm/debug.h>
  26
  27 #define DEBUG_PROLOG_ENTRY -1
  28
  29 #define ALL_AREAS 0 /* copy all debug areas */
  30 #define NO_AREAS  1 /* copy no debug areas */
  31
  32 /* typedefs */
  33
  34 typedef struct file_private_info {
  35         loff_t offset;                  /* offset of last read in file */
  36         int    act_area;                /* number of last formated area */
  37         int    act_page;                /* act page in given area */
  38         int    act_entry;               /* last formated entry (offset */
  39                                         /* relative to beginning of last */
  40                                         /* formated page) */
  41         size_t act_entry_offset;        /* up to this offset we copied */
  42                                         /* in last read the last formated */
  43                                         /* entry to userland */
  44         char   temp_buf[2048];          /* buffer for output */
  45         debug_info_t *debug_info_org;   /* original debug information */
  46         debug_info_t *debug_info_snap;  /* snapshot of debug information */
  47         struct debug_view *view;        /* used view of debug info */
  48 } file_private_info_t;
  49
  50 typedef struct
  51 {
  52         char *string;
  53         /*
  54          * This assumes that all args are converted into longs
  55          * on L/390 this is the case for all types of parameter
  56          * except of floats, and long long (32 bit)
  57          *
  58          */
  59         long args[0];
  60 } debug_sprintf_entry_t;
  61
  62
  63 extern void tod_to_timeval(uint64_t todval, struct timespec *xtime);
  64
  65 /* internal function prototyes */
  66
  67 static int debug_init(void);
  68 static ssize_t debug_output(struct file *file, char __user *user_buf,
  69                         size_t user_len, loff_t * offset);
  70 static ssize_t debug_input(struct file *file, const char __user *user_buf,
  71                         size_t user_len, loff_t * offset);
  72 static int debug_open(struct inode *inode, struct file *file);
  73 static int debug_close(struct inode *inode, struct file *file);
  74 static debug_info_t *debug_info_create(const char *name, int pages_per_area,
  75                         int nr_areas, int buf_size, mode_t mode);
  76 static void debug_info_get(debug_info_t *);
  77 static void debug_info_put(debug_info_t *);
  78 static int debug_prolog_level_fn(debug_info_t * id,
  79                         struct debug_view *view, char *out_buf);
  80 static int debug_input_level_fn(debug_info_t * id, struct debug_view *view,
  81                         struct file *file, const char __user *user_buf,
  82                         size_t user_buf_size, loff_t * offset);
  83 static int debug_prolog_pages_fn(debug_info_t * id,
  84                         struct debug_view *view, char *out_buf);
  85 static int debug_input_pages_fn(debug_info_t * id, struct debug_view *view,
  86                         struct file *file, const char __user *user_buf,
  87                         size_t user_buf_size, loff_t * offset);
  88 static int debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
  89                         struct file *file, const char __user *user_buf,
  90                         size_t user_buf_size, loff_t * offset);
  91 static int debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
  92                         char *out_buf, const char *in_buf);
  93 static int debug_raw_format_fn(debug_info_t * id,
  94                         struct debug_view *view, char *out_buf,
  95                         const char *in_buf);
  96 static int debug_raw_header_fn(debug_info_t * id, struct debug_view *view,
  97                         int area, debug_entry_t * entry, char *out_buf);
  98
  99 static int debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view,
 100                         char *out_buf, debug_sprintf_entry_t *curr_event);
 101
 102 /* globals */
 103
 104 struct debug_view debug_raw_view = {
 105         "raw",
 106         NULL,
 107         &debug_raw_header_fn,
 108         &debug_raw_format_fn,
 109         NULL,
 110         NULL
 111 };
 112
 113 struct debug_view debug_hex_ascii_view = {
 114         "hex_ascii",
 115         NULL,
 116         &debug_dflt_header_fn,
 117         &debug_hex_ascii_format_fn,
 118         NULL,
 119         NULL
 120 };
 121
 122 static struct debug_view debug_level_view = {
 123         "level",
 124         &debug_prolog_level_fn,
 125         NULL,
 126         NULL,
 127         &debug_input_level_fn,
 128         NULL
 129 };
 130
 131 static struct debug_view debug_pages_view = {
 132         "pages",
 133         &debug_prolog_pages_fn,
 134         NULL,
 135         NULL,
 136         &debug_input_pages_fn,
 137         NULL
 138 };
 139
 140 static struct debug_view debug_flush_view = {
 141         "flush",
 142         NULL,
 143         NULL,
 144         NULL,
 145         &debug_input_flush_fn,
 146         NULL
 147 };
 148
 149 struct debug_view debug_sprintf_view = {
 150         "sprintf",
 151         NULL,
 152         &debug_dflt_header_fn,
 153         (debug_format_proc_t*)&debug_sprintf_format_fn,
 154         NULL,
 155         NULL
 156 };
 157
 158 /* used by dump analysis tools to determine version of debug feature */
 159 static unsigned int __used debug_feature_version = __DEBUG_FEATURE_VERSION;
 160
 161 /* static globals */
 162
 163 static debug_info_t *debug_area_first = NULL;
 164 static debug_info_t *debug_area_last = NULL;
 165 static DEFINE_MUTEX(debug_mutex);
 166
 167 static int initialized;
 168
 169 static const struct file_operations debug_file_ops = {
 170         .owner   = THIS_MODULE,
 171         .read    = debug_output,
 172         .write   = debug_input,
 173         .open    = debug_open,
 174         .release = debug_close,
 175 };
 176
 177 static struct dentry *debug_debugfs_root_entry;
 178
 179 /* functions */
 180
 181 /*
 182  * debug_areas_alloc
 183  * - Debug areas are implemented as a threedimensonal array:
 184  *   areas[areanumber][pagenumber][pageoffset]
 185  */
 186
 187 static debug_entry_t***
 188 debug_areas_alloc(int pages_per_area, int nr_areas)
 189 {
 190         debug_entry_t*** areas;
 191         int i,j;
 192
 193         areas = kmalloc(nr_areas *
 194                                         sizeof(debug_entry_t**),
 195                                         GFP_KERNEL);
 196         if (!areas)
 197                 goto fail_malloc_areas;
 198         for (i = 0; i < nr_areas; i++) {
 199                 areas[i] = kmalloc(pages_per_area *
 200                                 sizeof(debug_entry_t*),GFP_KERNEL);
 201                 if (!areas[i]) {
 202                         goto fail_malloc_areas2;
 203                 }
 204                 for(j = 0; j < pages_per_area; j++) {
 205                         areas[i][j] = kzalloc(PAGE_SIZE, GFP_KERNEL);
 206                         if(!areas[i][j]) {
 207                                 for(j--; j >=0 ; j--) {
 208                                         kfree(areas[i][j]);
 209                                 }
 210                                 kfree(areas[i]);
 211                                 goto fail_malloc_areas2;
 212                         }
 213                 }
 214         }
 215         return areas;
 216
 217 fail_malloc_areas2:
 218         for(i--; i >= 0; i--){
 219                 for(j=0; j < pages_per_area;j++){
 220                         kfree(areas[i][j]);
 221                 }
 222                 kfree(areas[i]);
 223         }
 224         kfree(areas);
 225 fail_malloc_areas:
 226         return NULL;
 227
 228 }
 229
 230
 231 /*
 232  * debug_info_alloc
 233  * - alloc new debug-info
 234  */
 235
 236 static debug_info_t*
 237 debug_info_alloc(const char *name, int pages_per_area, int nr_areas,
 238                  int buf_size, int level, int mode)
 239 {
 240         debug_info_t* rc;
 241
 242         /* alloc everything */
 243
 244         rc = kmalloc(sizeof(debug_info_t), GFP_KERNEL);
 245         if(!rc)
 246                 goto fail_malloc_rc;
 247         rc->active_entries = kcalloc(nr_areas, sizeof(int), GFP_KERNEL);
 248         if(!rc->active_entries)
 249                 goto fail_malloc_active_entries;
 250         rc->active_pages = kcalloc(nr_areas, sizeof(int), GFP_KERNEL);
 251         if(!rc->active_pages)
 252                 goto fail_malloc_active_pages;
 253         if((mode == ALL_AREAS) && (pages_per_area != 0)){
 254                 rc->areas = debug_areas_alloc(pages_per_area, nr_areas);
 255                 if(!rc->areas)
 256                         goto fail_malloc_areas;
 257         } else {
 258                 rc->areas = NULL;
 259         }
 260
 261         /* initialize members */
 262
 263         spin_lock_init(&rc->lock);
 264         rc->pages_per_area = pages_per_area;
 265         rc->nr_areas       = nr_areas;
 266         rc->active_area    = 0;
 267         rc->level          = level;
 268         rc->buf_size       = buf_size;
 269         rc->entry_size     = sizeof(debug_entry_t) + buf_size;
 270         strlcpy(rc->name, name, sizeof(rc->name));
 271         memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *));
 272         memset(rc->debugfs_entries, 0 ,DEBUG_MAX_VIEWS *
 273                 sizeof(struct dentry*));
 274         atomic_set(&(rc->ref_count), 0);
 275
 276         return rc;
 277
 278 fail_malloc_areas:
 279         kfree(rc->active_pages);
 280 fail_malloc_active_pages:
 281         kfree(rc->active_entries);
 282 fail_malloc_active_entries:
 283         kfree(rc);
 284 fail_malloc_rc:
 285         return NULL;
 286 }
 287
 288 /*
 289  * debug_areas_free
 290  * - free all debug areas
 291  */
 292
 293 static void
 294 debug_areas_free(debug_info_t* db_info)
 295 {
 296         int i,j;
 297
 298         if(!db_info->areas)
 299                 return;
 300         for (i = 0; i < db_info->nr_areas; i++) {
 301                 for(j = 0; j < db_info->pages_per_area; j++) {
 302                         kfree(db_info->areas[i][j]);
 303                 }
 304                 kfree(db_info->areas[i]);
 305         }
 306         kfree(db_info->areas);
 307         db_info->areas = NULL;
 308 }
 309
 310 /*
 311  * debug_info_free
 312  * - free memory debug-info
 313  */
 314
 315 static void
 316 debug_info_free(debug_info_t* db_info){
 317         debug_areas_free(db_info);
 318         kfree(db_info->active_entries);
 319         kfree(db_info->active_pages);
 320         kfree(db_info);
 321 }
 322
 323 /*
 324  * debug_info_create
 325  * - create new debug-info
 326  */
 327
 328 static debug_info_t*
 329 debug_info_create(const char *name, int pages_per_area, int nr_areas,
 330                   int buf_size, mode_t mode)
 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         rc->mode = mode & ~S_IFMT;
 340
 341         /* create root directory */
 342         rc->debugfs_root_entry = debugfs_create_dir(rc->name,
 343                                         debug_debugfs_root_entry);
 344
 345         /* append new element to linked list */
 346         if (!debug_area_first) {
 347                 /* first element in list */
 348                 debug_area_first = rc;
 349                 rc->prev = NULL;
 350         } else {
 351                 /* append element to end of list */
 352                 debug_area_last->next = rc;
 353                 rc->prev = debug_area_last;
 354         }
 355         debug_area_last = rc;
 356         rc->next = NULL;
 357
 358         debug_info_get(rc);
 359 out:
 360         return rc;
 361 }
 362
 363 /*
 364  * debug_info_copy
 365  * - copy debug-info
 366  */
 367
 368 static debug_info_t*
 369 debug_info_copy(debug_info_t* in, int mode)
 370 {
 371         int i,j;
 372         debug_info_t* rc;
 373         unsigned long flags;
 374
 375         /* get a consistent copy of the debug areas */
 376         do {
 377                 rc = debug_info_alloc(in->name, in->pages_per_area,
 378                         in->nr_areas, in->buf_size, in->level, mode);
 379                 spin_lock_irqsave(&in->lock, flags);
 380                 if(!rc)
 381                         goto out;
 382                 /* has something changed in the meantime ? */
 383                 if((rc->pages_per_area == in->pages_per_area) &&
 384                    (rc->nr_areas == in->nr_areas)) {
 385                         break;
 386                 }
 387                 spin_unlock_irqrestore(&in->lock, flags);
 388                 debug_info_free(rc);
 389         } while (1);
 390
 391         if(!rc || (mode == NO_AREAS))
 392                 goto out;
 393
 394         for(i = 0; i < in->nr_areas; i++){
 395                 for(j = 0; j < in->pages_per_area; j++) {
 396                         memcpy(rc->areas[i][j], in->areas[i][j],PAGE_SIZE);
 397                 }
 398         }
 399 out:
 400         spin_unlock_irqrestore(&in->lock, flags);
 401         return rc;
 402 }
 403
 404 /*
 405  * debug_info_get
 406  * - increments reference count for debug-info
 407  */
 408
 409 static void
 410 debug_info_get(debug_info_t * db_info)
 411 {
 412         if (db_info)
 413                 atomic_inc(&db_info->ref_count);
 414 }
 415
 416 /*
 417  * debug_info_put:
 418  * - decreases reference count for debug-info and frees it if necessary
 419  */
 420
 421 static void
 422 debug_info_put(debug_info_t *db_info)
 423 {
 424         int i;
 425
 426         if (!db_info)
 427                 return;
 428         if (atomic_dec_and_test(&db_info->ref_count)) {
 429                 for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
 430                         if (!db_info->views[i])
 431                                 continue;
 432                         debugfs_remove(db_info->debugfs_entries[i]);
 433                 }
 434                 debugfs_remove(db_info->debugfs_root_entry);
 435                 if(db_info == debug_area_first)
 436                         debug_area_first = db_info->next;
 437                 if(db_info == debug_area_last)
 438                         debug_area_last = db_info->prev;
 439                 if(db_info->prev) db_info->prev->next = db_info->next;
 440                 if(db_info->next) db_info->next->prev = db_info->prev;
 441                 debug_info_free(db_info);
 442         }
 443 }
 444
 445 /*
 446  * debug_format_entry:
 447  * - format one debug entry and return size of formated data
 448  */
 449
 450 static int
 451 debug_format_entry(file_private_info_t *p_info)
 452 {
 453         debug_info_t *id_snap   = p_info->debug_info_snap;
 454         struct debug_view *view = p_info->view;
 455         debug_entry_t *act_entry;
 456         size_t len = 0;
 457         if(p_info->act_entry == DEBUG_PROLOG_ENTRY){
 458                 /* print prolog */
 459                 if (view->prolog_proc)
 460                         len += view->prolog_proc(id_snap,view,p_info->temp_buf);
 461                 goto out;
 462         }
 463         if (!id_snap->areas) /* this is true, if we have a prolog only view */
 464                 goto out;    /* or if 'pages_per_area' is 0 */
 465         act_entry = (debug_entry_t *) ((char*)id_snap->areas[p_info->act_area]
 466                                 [p_info->act_page] + p_info->act_entry);
 467
 468         if (act_entry->id.stck == 0LL)
 469                         goto out;  /* empty entry */
 470         if (view->header_proc)
 471                 len += view->header_proc(id_snap, view, p_info->act_area,
 472                                         act_entry, p_info->temp_buf + len);
 473         if (view->format_proc)
 474                 len += view->format_proc(id_snap, view, p_info->temp_buf + len,
 475                                                 DEBUG_DATA(act_entry));
 476 out:
 477         return len;
 478 }
 479
 480 /*
 481  * debug_next_entry:
 482  * - goto next entry in p_info
 483  */
 484
 485 static inline int
 486 debug_next_entry(file_private_info_t *p_info)
 487 {
 488         debug_info_t *id;
 489
 490         id = p_info->debug_info_snap;
 491         if(p_info->act_entry == DEBUG_PROLOG_ENTRY){
 492                 p_info->act_entry = 0;
 493                 p_info->act_page  = 0;
 494                 goto out;
 495         }
 496         if(!id->areas)
 497                 return 1;
 498         p_info->act_entry += id->entry_size;
 499         /* switch to next page, if we reached the end of the page  */
 500         if (p_info->act_entry > (PAGE_SIZE - id->entry_size)){
 501                 /* next page */
 502                 p_info->act_entry = 0;
 503                 p_info->act_page += 1;
 504                 if((p_info->act_page % id->pages_per_area) == 0) {
 505                         /* next area */
 506                         p_info->act_area++;
 507                         p_info->act_page=0;
 508                 }
 509                 if(p_info->act_area >= id->nr_areas)
 510                         return 1;
 511         }
 512 out:
 513         return 0;
 514 }
 515
 516 /*
 517  * debug_output:
 518  * - called for user read()
 519  * - copies formated debug entries to the user buffer
 520  */
 521
 522 static ssize_t
 523 debug_output(struct file *file,         /* file descriptor */
 524             char __user *user_buf,      /* user buffer */
 525             size_t  len,                /* length of buffer */
 526             loff_t *offset)             /* offset in the file */
 527 {
 528         size_t count = 0;
 529         size_t entry_offset;
 530         file_private_info_t *p_info;
 531
 532         p_info = ((file_private_info_t *) file->private_data);
 533         if (*offset != p_info->offset)
 534                 return -EPIPE;
 535         if(p_info->act_area >= p_info->debug_info_snap->nr_areas)
 536                 return 0;
 537         entry_offset = p_info->act_entry_offset;
 538         while(count < len){
 539                 int formatted_line_size;
 540                 int formatted_line_residue;
 541                 int user_buf_residue;
 542                 size_t copy_size;
 543
 544                 formatted_line_size = debug_format_entry(p_info);
 545                 formatted_line_residue = formatted_line_size - entry_offset;
 546                 user_buf_residue = len-count;
 547                 copy_size = min(user_buf_residue, formatted_line_residue);
 548                 if(copy_size){
 549                         if (copy_to_user(user_buf + count, p_info->temp_buf
 550                                         + entry_offset, copy_size))
 551                                 return -EFAULT;
 552                         count += copy_size;
 553                         entry_offset += copy_size;
 554                 }
 555                 if(copy_size == formatted_line_residue){
 556                         entry_offset = 0;
 557                         if(debug_next_entry(p_info))
 558                                 goto out;
 559                 }
 560         }
 561 out:
 562         p_info->offset           = *offset + count;
 563         p_info->act_entry_offset = entry_offset;
 564         *offset = p_info->offset;
 565         return count;
 566 }
 567
 568 /*
 569  * debug_input:
 570  * - called for user write()
 571  * - calls input function of view
 572  */
 573
 574 static ssize_t
 575 debug_input(struct file *file, const char __user *user_buf, size_t length,
 576                 loff_t *offset)
 577 {
 578         int rc = 0;
 579         file_private_info_t *p_info;
 580
 581         mutex_lock(&debug_mutex);
 582         p_info = ((file_private_info_t *) file->private_data);
 583         if (p_info->view->input_proc)
 584                 rc = p_info->view->input_proc(p_info->debug_info_org,
 585                                               p_info->view, file, user_buf,
 586                                               length, offset);
 587         else
 588                 rc = -EPERM;
 589         mutex_unlock(&debug_mutex);
 590         return rc;              /* number of input characters */
 591 }
 592
 593 /*
 594  * debug_open:
 595  * - called for user open()
 596  * - copies formated output to private_data area of the file
 597  *   handle
 598  */
 599
 600 static int
 601 debug_open(struct inode *inode, struct file *file)
 602 {
 603         int i = 0, rc = 0;
 604         file_private_info_t *p_info;
 605         debug_info_t *debug_info, *debug_info_snapshot;
 606
 607         mutex_lock(&debug_mutex);
 608         debug_info = file->f_path.dentry->d_inode->i_private;
 609         /* find debug view */
 610         for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
 611                 if (!debug_info->views[i])
 612                         continue;
 613                 else if (debug_info->debugfs_entries[i] ==
 614                          file->f_path.dentry) {
 615                         goto found;     /* found view ! */
 616                 }
 617         }
 618         /* no entry found */
 619         rc = -EINVAL;
 620         goto out;
 621
 622 found:
 623
 624         /* Make snapshot of current debug areas to get it consistent.     */
 625         /* To copy all the areas is only needed, if we have a view which  */
 626         /* formats the debug areas. */
 627
 628         if(!debug_info->views[i]->format_proc &&
 629                 !debug_info->views[i]->header_proc){
 630                 debug_info_snapshot = debug_info_copy(debug_info, NO_AREAS);
 631         } else {
 632                 debug_info_snapshot = debug_info_copy(debug_info, ALL_AREAS);
 633         }
 634
 635         if(!debug_info_snapshot){
 636                 rc = -ENOMEM;
 637                 goto out;
 638         }
 639         p_info = kmalloc(sizeof(file_private_info_t),
 640                                                 GFP_KERNEL);
 641         if(!p_info){
 642                 if(debug_info_snapshot)
 643                         debug_info_free(debug_info_snapshot);
 644                 rc = -ENOMEM;
 645                 goto out;
 646         }
 647         p_info->offset = 0;
 648         p_info->debug_info_snap = debug_info_snapshot;
 649         p_info->debug_info_org  = debug_info;
 650         p_info->view = debug_info->views[i];
 651         p_info->act_area = 0;
 652         p_info->act_page = 0;
 653         p_info->act_entry = DEBUG_PROLOG_ENTRY;
 654         p_info->act_entry_offset = 0;
 655         file->private_data = p_info;
 656         debug_info_get(debug_info);
 657 out:
 658         mutex_unlock(&debug_mutex);
 659         return rc;
 660 }
 661
 662 /*
 663  * debug_close:
 664  * - called for user close()
 665  * - deletes  private_data area of the file handle
 666  */
 667
 668 static int
 669 debug_close(struct inode *inode, struct file *file)
 670 {
 671         file_private_info_t *p_info;
 672         p_info = (file_private_info_t *) file->private_data;
 673         if(p_info->debug_info_snap)
 674                 debug_info_free(p_info->debug_info_snap);
 675         debug_info_put(p_info->debug_info_org);
 676         kfree(file->private_data);
 677         return 0;               /* success */
 678 }
 679
 680 /*
 681  * debug_register_mode:
 682  * - Creates and initializes debug area for the caller
 683  *   The mode parameter allows to specify access rights for the s390dbf files
 684  * - Returns handle for debug area
 685  */
 686
 687 debug_info_t *debug_register_mode(const char *name, int pages_per_area,
 688                                   int nr_areas, int buf_size, mode_t mode,
 689                                   uid_t uid, gid_t gid)
 690 {
 691         debug_info_t *rc = NULL;
 692
 693         /* Since debugfs currently does not support uid/gid other than root, */
 694         /* we do not allow gid/uid != 0 until we get support for that. */
 695         if ((uid != 0) || (gid != 0))
 696                 printk(KERN_WARNING "debug: Warning - Currently only uid/gid "
 697                        "= 0 are supported. Using root as owner now!");
 698         if (!initialized)
 699                 BUG();
 700         mutex_lock(&debug_mutex);
 701
 702         /* create new debug_info */
 703
 704         rc = debug_info_create(name, pages_per_area, nr_areas, buf_size, mode);
 705         if(!rc)
 706                 goto out;
 707         debug_register_view(rc, &debug_level_view);
 708         debug_register_view(rc, &debug_flush_view);
 709         debug_register_view(rc, &debug_pages_view);
 710 out:
 711         if (!rc){
 712                 printk(KERN_ERR "debug: debug_register failed for %s\n",name);
 713         }
 714         mutex_unlock(&debug_mutex);
 715         return rc;
 716 }
 717 EXPORT_SYMBOL(debug_register_mode);
 718
 719 /*
 720  * debug_register:
 721  * - creates and initializes debug area for the caller
 722  * - returns handle for debug area
 723  */
 724
 725 debug_info_t *debug_register(const char *name, int pages_per_area,
 726                              int nr_areas, int buf_size)
 727 {
 728         return debug_register_mode(name, pages_per_area, nr_areas, buf_size,
 729                                    S_IRUSR | S_IWUSR, 0, 0);
 730 }
 731
 732 /*
 733  * debug_unregister:
 734  * - give back debug area
 735  */
 736
 737 void
 738 debug_unregister(debug_info_t * id)
 739 {
 740         if (!id)
 741                 goto out;
 742         mutex_lock(&debug_mutex);
 743         debug_info_put(id);
 744         mutex_unlock(&debug_mutex);
 745
 746 out:
 747         return;
 748 }
 749
 750 /*
 751  * debug_set_size:
 752  * - set area size (number of pages) and number of areas
 753  */
 754 static int
 755 debug_set_size(debug_info_t* id, int nr_areas, int pages_per_area)
 756 {
 757         unsigned long flags;
 758         debug_entry_t *** new_areas;
 759         int rc=0;
 760
 761         if(!id || (nr_areas <= 0) || (pages_per_area < 0))
 762                 return -EINVAL;
 763         if(pages_per_area > 0){
 764                 new_areas = debug_areas_alloc(pages_per_area, nr_areas);
 765                 if(!new_areas) {
 766                         printk(KERN_WARNING "debug: could not allocate memory "\
 767                                          "for pagenumber: %i\n",pages_per_area);
 768                         rc = -ENOMEM;
 769                         goto out;
 770                 }
 771         } else {
 772                 new_areas = NULL;
 773         }
 774         spin_lock_irqsave(&id->lock,flags);
 775         debug_areas_free(id);
 776         id->areas = new_areas;
 777         id->nr_areas = nr_areas;
 778         id->pages_per_area = pages_per_area;
 779         id->active_area = 0;
 780         memset(id->active_entries,0,sizeof(int)*id->nr_areas);
 781         memset(id->active_pages, 0, sizeof(int)*id->nr_areas);
 782         spin_unlock_irqrestore(&id->lock,flags);
 783         printk(KERN_INFO "debug: %s: set new size (%i pages)\n"\
 784                          ,id->name, pages_per_area);
 785 out:
 786         return rc;
 787 }
 788
 789 /*
 790  * debug_set_level:
 791  * - set actual debug level
 792  */
 793
 794 void
 795 debug_set_level(debug_info_t* id, int new_level)
 796 {
 797         unsigned long flags;
 798         if(!id)
 799                 return;
 800         spin_lock_irqsave(&id->lock,flags);
 801         if(new_level == DEBUG_OFF_LEVEL){
 802                 id->level = DEBUG_OFF_LEVEL;
 803                 printk(KERN_INFO "debug: %s: switched off\n",id->name);
 804         } else if ((new_level > DEBUG_MAX_LEVEL) || (new_level < 0)) {
 805                 printk(KERN_INFO
 806                         "debug: %s: level %i is out of range (%i - %i)\n",
 807                         id->name, new_level, 0, DEBUG_MAX_LEVEL);
 808         } else {
 809                 id->level = new_level;
 810         }
 811         spin_unlock_irqrestore(&id->lock,flags);
 812 }
 813
 814
 815 /*
 816  * proceed_active_entry:
 817  * - set active entry to next in the ring buffer
 818  */
 819
 820 static inline void
 821 proceed_active_entry(debug_info_t * id)
 822 {
 823         if ((id->active_entries[id->active_area] += id->entry_size)
 824             > (PAGE_SIZE - id->entry_size)){
 825                 id->active_entries[id->active_area] = 0;
 826                 id->active_pages[id->active_area] =
 827                         (id->active_pages[id->active_area] + 1) %
 828                         id->pages_per_area;
 829         }
 830 }
 831
 832 /*
 833  * proceed_active_area:
 834  * - set active area to next in the ring buffer
 835  */
 836
 837 static inline void
 838 proceed_active_area(debug_info_t * id)
 839 {
 840         id->active_area++;
 841         id->active_area = id->active_area % id->nr_areas;
 842 }
 843
 844 /*
 845  * get_active_entry:
 846  */
 847
 848 static inline debug_entry_t*
 849 get_active_entry(debug_info_t * id)
 850 {
 851         return (debug_entry_t *) (((char *) id->areas[id->active_area]
 852                                         [id->active_pages[id->active_area]]) +
 853                                         id->active_entries[id->active_area]);
 854 }
 855
 856 /*
 857  * debug_finish_entry:
 858  * - set timestamp, caller address, cpu number etc.
 859  */
 860
 861 static inline void
 862 debug_finish_entry(debug_info_t * id, debug_entry_t* active, int level,
 863                         int exception)
 864 {
 865         active->id.stck = get_clock();
 866         active->id.fields.cpuid = smp_processor_id();
 867         active->caller = __builtin_return_address(0);
 868         active->id.fields.exception = exception;
 869         active->id.fields.level     = level;
 870         proceed_active_entry(id);
 871         if(exception)
 872                 proceed_active_area(id);
 873 }
 874
 875 static int debug_stoppable=1;
 876 static int debug_active=1;
 877
 878 #define CTL_S390DBF_STOPPABLE 5678
 879 #define CTL_S390DBF_ACTIVE 5679
 880
 881 /*
 882  * proc handler for the running debug_active sysctl
 883  * always allow read, allow write only if debug_stoppable is set or
 884  * if debug_active is already off
 885  */
 886 static int
 887 s390dbf_procactive(ctl_table *table, int write, struct file *filp,
 888                      void __user *buffer, size_t *lenp, loff_t *ppos)
 889 {
 890         if (!write || debug_stoppable || !debug_active)
 891                 return proc_dointvec(table, write, filp, buffer, lenp, ppos);
 892         else
 893                 return 0;
 894 }
 895
 896
 897 static struct ctl_table s390dbf_table[] = {
 898         {
 899                 .ctl_name       = CTL_S390DBF_STOPPABLE,
 900                 .procname       = "debug_stoppable",
 901                 .data           = &debug_stoppable,
 902                 .maxlen         = sizeof(int),
 903                 .mode           = S_IRUGO | S_IWUSR,
 904                 .proc_handler   = &proc_dointvec,
 905                 .strategy       = &sysctl_intvec,
 906         },
 907          {
 908                 .ctl_name       = CTL_S390DBF_ACTIVE,
 909                 .procname       = "debug_active",
 910                 .data           = &debug_active,
 911                 .maxlen         = sizeof(int),
 912                 .mode           = S_IRUGO | S_IWUSR,
 913                 .proc_handler   = &s390dbf_procactive,
 914                 .strategy       = &sysctl_intvec,
 915         },
 916         { .ctl_name = 0 }
 917 };
 918
 919 static struct ctl_table s390dbf_dir_table[] = {
 920         {
 921                 .ctl_name       = CTL_S390DBF,
 922                 .procname       = "s390dbf",
 923                 .maxlen         = 0,
 924                 .mode           = S_IRUGO | S_IXUGO,
 925                 .child          = s390dbf_table,
 926         },
 927         { .ctl_name = 0 }
 928 };
 929
 930 static struct ctl_table_header *s390dbf_sysctl_header;
 931
 932 void
 933 debug_stop_all(void)
 934 {
 935         if (debug_stoppable)
 936                 debug_active = 0;
 937 }
 938
 939
 940 /*
 941  * debug_event_common:
 942  * - write debug entry with given size
 943  */
 944
 945 debug_entry_t*
 946 debug_event_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, 0);
 958         spin_unlock_irqrestore(&id->lock, flags);
 959
 960         return active;
 961 }
 962
 963 /*
 964  * debug_exception_common:
 965  * - write debug entry with given size and switch to next debug area
 966  */
 967
 968 debug_entry_t
 969 *debug_exception_common(debug_info_t * id, int level, const void *buf, int len)
 970 {
 971         unsigned long flags;
 972         debug_entry_t *active;
 973
 974         if (!debug_active || !id->areas)
 975                 return NULL;
 976         spin_lock_irqsave(&id->lock, flags);
 977         active = get_active_entry(id);
 978         memset(DEBUG_DATA(active), 0, id->buf_size);
 979         memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
 980         debug_finish_entry(id, active, level, 1);
 981         spin_unlock_irqrestore(&id->lock, flags);
 982
 983         return active;
 984 }
 985
 986 /*
 987  * counts arguments in format string for sprintf view
 988  */
 989
 990 static inline int
 991 debug_count_numargs(char *string)
 992 {
 993         int numargs=0;
 994
 995         while(*string) {
 996                 if(*string++=='%')
 997                         numargs++;
 998         }
 999         return(numargs);
1000 }
1001
1002 /*
1003  * debug_sprintf_event:
1004  */
1005
1006 debug_entry_t*
1007 debug_sprintf_event(debug_info_t* id, int level,char *string,...)
1008 {
1009         va_list   ap;
1010         int numargs,idx;
1011         unsigned long flags;
1012         debug_sprintf_entry_t *curr_event;
1013         debug_entry_t *active;
1014
1015         if((!id) || (level > id->level))
1016                 return NULL;
1017         if (!debug_active || !id->areas)
1018                 return NULL;
1019         numargs=debug_count_numargs(string);
1020
1021         spin_lock_irqsave(&id->lock, flags);
1022         active = get_active_entry(id);
1023         curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active);
1024         va_start(ap,string);
1025         curr_event->string=string;
1026         for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
1027                 curr_event->args[idx]=va_arg(ap,long);
1028         va_end(ap);
1029         debug_finish_entry(id, active, level, 0);
1030         spin_unlock_irqrestore(&id->lock, flags);
1031
1032         return active;
1033 }
1034
1035 /*
1036  * debug_sprintf_exception:
1037  */
1038
1039 debug_entry_t*
1040 debug_sprintf_exception(debug_info_t* id, int level,char *string,...)
1041 {
1042         va_list   ap;
1043         int numargs,idx;
1044         unsigned long flags;
1045         debug_sprintf_entry_t *curr_event;
1046         debug_entry_t *active;
1047
1048         if((!id) || (level > id->level))
1049                 return NULL;
1050         if (!debug_active || !id->areas)
1051                 return NULL;
1052
1053         numargs=debug_count_numargs(string);
1054
1055         spin_lock_irqsave(&id->lock, flags);
1056         active = get_active_entry(id);
1057         curr_event=(debug_sprintf_entry_t *)DEBUG_DATA(active);
1058         va_start(ap,string);
1059         curr_event->string=string;
1060         for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
1061                 curr_event->args[idx]=va_arg(ap,long);
1062         va_end(ap);
1063         debug_finish_entry(id, active, level, 1);
1064         spin_unlock_irqrestore(&id->lock, flags);
1065
1066         return active;
1067 }
1068
1069 /*
1070  * debug_init:
1071  * - is called exactly once to initialize the debug feature
1072  */
1073
1074 static int
1075 __init debug_init(void)
1076 {
1077         int rc = 0;
1078
1079         s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table);
1080         mutex_lock(&debug_mutex);
1081         debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT,NULL);
1082         initialized = 1;
1083         mutex_unlock(&debug_mutex);
1084
1085         return rc;
1086 }
1087
1088 /*
1089  * debug_register_view:
1090  */
1091
1092 int
1093 debug_register_view(debug_info_t * id, struct debug_view *view)
1094 {
1095         int rc = 0;
1096         int i;
1097         unsigned long flags;
1098         mode_t mode;
1099         struct dentry *pde;
1100
1101         if (!id)
1102                 goto out;
1103         mode = (id->mode | S_IFREG) & ~S_IXUGO;
1104         if (!(view->prolog_proc || view->format_proc || view->header_proc))
1105                 mode &= ~(S_IRUSR | S_IRGRP | S_IROTH);
1106         if (!view->input_proc)
1107                 mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);
1108         pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry,
1109                                 id , &debug_file_ops);
1110         if (!pde){
1111                 printk(KERN_WARNING "debug: debugfs_create_file() failed!"\
1112                         " Cannot register view %s/%s\n", id->name,view->name);
1113                 rc = -1;
1114                 goto out;
1115         }
1116         spin_lock_irqsave(&id->lock, flags);
1117         for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1118                 if (!id->views[i])
1119                         break;
1120         }
1121         if (i == DEBUG_MAX_VIEWS) {
1122                 printk(KERN_WARNING "debug: cannot register view %s/%s\n",
1123                         id->name,view->name);
1124                 printk(KERN_WARNING
1125                         "debug: maximum number of views reached (%i)!\n", i);
1126                 debugfs_remove(pde);
1127                 rc = -1;
1128         } else {
1129                 id->views[i] = view;
1130                 id->debugfs_entries[i] = pde;
1131         }
1132         spin_unlock_irqrestore(&id->lock, flags);
1133 out:
1134         return rc;
1135 }
1136
1137 /*
1138  * debug_unregister_view:
1139  */
1140
1141 int
1142 debug_unregister_view(debug_info_t * id, struct debug_view *view)
1143 {
1144         int rc = 0;
1145         int i;
1146         unsigned long flags;
1147
1148         if (!id)
1149                 goto out;
1150         spin_lock_irqsave(&id->lock, flags);
1151         for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1152                 if (id->views[i] == view)
1153                         break;
1154         }
1155         if (i == DEBUG_MAX_VIEWS)
1156                 rc = -1;
1157         else {
1158                 debugfs_remove(id->debugfs_entries[i]);
1159                 id->views[i] = NULL;
1160                 rc = 0;
1161         }
1162         spin_unlock_irqrestore(&id->lock, flags);
1163 out:
1164         return rc;
1165 }
1166
1167 static inline char *
1168 debug_get_user_string(const char __user *user_buf, size_t user_len)
1169 {
1170         char* buffer;
1171
1172         buffer = kmalloc(user_len + 1, GFP_KERNEL);
1173         if (!buffer)
1174                 return ERR_PTR(-ENOMEM);
1175         if (copy_from_user(buffer, user_buf, user_len) != 0) {
1176                 kfree(buffer);
1177                 return ERR_PTR(-EFAULT);
1178         }
1179         /* got the string, now strip linefeed. */
1180         if (buffer[user_len - 1] == '\n')
1181                 buffer[user_len - 1] = 0;
1182         else
1183                 buffer[user_len] = 0;
1184         return buffer;
1185 }
1186
1187 static inline int
1188 debug_get_uint(char *buf)
1189 {
1190         int rc;
1191
1192         for(; isspace(*buf); buf++);
1193         rc = simple_strtoul(buf, &buf, 10);
1194         if(*buf){
1195                 rc = -EINVAL;
1196         }
1197         return rc;
1198 }
1199
1200 /*
1201  * functions for debug-views
1202  ***********************************
1203 */
1204
1205 /*
1206  * prints out actual debug level
1207  */
1208
1209 static int
1210 debug_prolog_pages_fn(debug_info_t * id,
1211                                  struct debug_view *view, char *out_buf)
1212 {
1213         return sprintf(out_buf, "%i\n", id->pages_per_area);
1214 }
1215
1216 /*
1217  * reads new size (number of pages per debug area)
1218  */
1219
1220 static int
1221 debug_input_pages_fn(debug_info_t * id, struct debug_view *view,
1222                         struct file *file, const char __user *user_buf,
1223                         size_t user_len, loff_t * offset)
1224 {
1225         char *str;
1226         int rc,new_pages;
1227
1228         if (user_len > 0x10000)
1229                 user_len = 0x10000;
1230         if (*offset != 0){
1231                 rc = -EPIPE;
1232                 goto out;
1233         }
1234         str = debug_get_user_string(user_buf,user_len);
1235         if(IS_ERR(str)){
1236                 rc = PTR_ERR(str);
1237                 goto out;
1238         }
1239         new_pages = debug_get_uint(str);
1240         if(new_pages < 0){
1241                 rc = -EINVAL;
1242                 goto free_str;
1243         }
1244         rc = debug_set_size(id,id->nr_areas, new_pages);
1245         if(rc != 0){
1246                 rc = -EINVAL;
1247                 goto free_str;
1248         }
1249         rc = user_len;
1250 free_str:
1251         kfree(str);
1252 out:
1253         *offset += user_len;
1254         return rc;              /* number of input characters */
1255 }
1256
1257 /*
1258  * prints out actual debug level
1259  */
1260
1261 static int
1262 debug_prolog_level_fn(debug_info_t * id, struct debug_view *view, char *out_buf)
1263 {
1264         int rc = 0;
1265
1266         if(id->level == DEBUG_OFF_LEVEL) {
1267                 rc = sprintf(out_buf,"-\n");
1268         }
1269         else {
1270                 rc = sprintf(out_buf, "%i\n", id->level);
1271         }
1272         return rc;
1273 }
1274
1275 /*
1276  * reads new debug level
1277  */
1278
1279 static int
1280 debug_input_level_fn(debug_info_t * id, struct debug_view *view,
1281                         struct file *file, const char __user *user_buf,
1282                         size_t user_len, loff_t * offset)
1283 {
1284         char *str;
1285         int rc,new_level;
1286
1287         if (user_len > 0x10000)
1288                 user_len = 0x10000;
1289         if (*offset != 0){
1290                 rc = -EPIPE;
1291                 goto out;
1292         }
1293         str = debug_get_user_string(user_buf,user_len);
1294         if(IS_ERR(str)){
1295                 rc = PTR_ERR(str);
1296                 goto out;
1297         }
1298         if(str[0] == '-'){
1299                 debug_set_level(id, DEBUG_OFF_LEVEL);
1300                 rc = user_len;
1301                 goto free_str;
1302         } else {
1303                 new_level = debug_get_uint(str);
1304         }
1305         if(new_level < 0) {
1306                 printk(KERN_INFO "debug: level `%s` is not valid\n", str);
1307                 rc = -EINVAL;
1308         } else {
1309                 debug_set_level(id, new_level);
1310                 rc = user_len;
1311         }
1312 free_str:
1313         kfree(str);
1314 out:
1315         *offset += user_len;
1316         return rc;              /* number of input characters */
1317 }
1318
1319
1320 /*
1321  * flushes debug areas
1322  */
1323
1324 static void debug_flush(debug_info_t* id, int area)
1325 {
1326         unsigned long flags;
1327         int i,j;
1328
1329         if(!id || !id->areas)
1330                 return;
1331         spin_lock_irqsave(&id->lock,flags);
1332         if(area == DEBUG_FLUSH_ALL){
1333                 id->active_area = 0;
1334                 memset(id->active_entries, 0, id->nr_areas * sizeof(int));
1335                 for (i = 0; i < id->nr_areas; i++) {
1336                         id->active_pages[i] = 0;
1337                         for(j = 0; j < id->pages_per_area; j++) {
1338                                 memset(id->areas[i][j], 0, PAGE_SIZE);
1339                         }
1340                 }
1341         } else if(area >= 0 && area < id->nr_areas) {
1342                 id->active_entries[area] = 0;
1343                 id->active_pages[area] = 0;
1344                 for(i = 0; i < id->pages_per_area; i++) {
1345                         memset(id->areas[area][i],0,PAGE_SIZE);
1346                 }
1347         }
1348         spin_unlock_irqrestore(&id->lock,flags);
1349 }
1350
1351 /*
1352  * view function: flushes debug areas
1353  */
1354
1355 static int
1356 debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
1357                         struct file *file, const char __user *user_buf,
1358                         size_t user_len, loff_t * offset)
1359 {
1360         char input_buf[1];
1361         int rc = user_len;
1362
1363         if (user_len > 0x10000)
1364                 user_len = 0x10000;
1365         if (*offset != 0){
1366                 rc = -EPIPE;
1367                 goto out;
1368         }
1369         if (copy_from_user(input_buf, user_buf, 1)){
1370                 rc = -EFAULT;
1371                 goto out;
1372         }
1373         if(input_buf[0] == '-') {
1374                 debug_flush(id, DEBUG_FLUSH_ALL);
1375                 goto out;
1376         }
1377         if (isdigit(input_buf[0])) {
1378                 int area = ((int) input_buf[0] - (int) '0');
1379                 debug_flush(id, area);
1380                 goto out;
1381         }
1382
1383         printk(KERN_INFO "debug: area `%c` is not valid\n", input_buf[0]);
1384
1385 out:
1386         *offset += user_len;
1387         return rc;              /* number of input characters */
1388 }
1389
1390 /*
1391  * prints debug header in raw format
1392  */
1393
1394 static int
1395 debug_raw_header_fn(debug_info_t * id, struct debug_view *view,
1396                         int area, debug_entry_t * entry, char *out_buf)
1397 {
1398         int rc;
1399
1400         rc = sizeof(debug_entry_t);
1401         memcpy(out_buf,entry,sizeof(debug_entry_t));
1402         return rc;
1403 }
1404
1405 /*
1406  * prints debug data in raw format
1407  */
1408
1409 static int
1410 debug_raw_format_fn(debug_info_t * id, struct debug_view *view,
1411                                char *out_buf, const char *in_buf)
1412 {
1413         int rc;
1414
1415         rc = id->buf_size;
1416         memcpy(out_buf, in_buf, id->buf_size);
1417         return rc;
1418 }
1419
1420 /*
1421  * prints debug data in hex/ascii format
1422  */
1423
1424 static int
1425 debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
1426                           char *out_buf, const char *in_buf)
1427 {
1428         int i, rc = 0;
1429
1430         for (i = 0; i < id->buf_size; i++) {
1431                 rc += sprintf(out_buf + rc, "%02x ",
1432                               ((unsigned char *) in_buf)[i]);
1433         }
1434         rc += sprintf(out_buf + rc, "| ");
1435         for (i = 0; i < id->buf_size; i++) {
1436                 unsigned char c = in_buf[i];
1437                 if (!isprint(c))
1438                         rc += sprintf(out_buf + rc, ".");
1439                 else
1440                         rc += sprintf(out_buf + rc, "%c", c);
1441         }
1442         rc += sprintf(out_buf + rc, "\n");
1443         return rc;
1444 }
1445
1446 /*
1447  * prints header for debug entry
1448  */
1449
1450 int
1451 debug_dflt_header_fn(debug_info_t * id, struct debug_view *view,
1452                          int area, debug_entry_t * entry, char *out_buf)
1453 {
1454         struct timespec time_spec;
1455         unsigned long long time;
1456         char *except_str;
1457         unsigned long caller;
1458         int rc = 0;
1459         unsigned int level;
1460
1461         level = entry->id.fields.level;
1462         time = entry->id.stck;
1463         /* adjust todclock to 1970 */
1464         time -= 0x8126d60e46000000LL - (0x3c26700LL * 1000000 * 4096);
1465         tod_to_timeval(time, &time_spec);
1466
1467         if (entry->id.fields.exception)
1468                 except_str = "*";
1469         else
1470                 except_str = "-";
1471         caller = ((unsigned long) entry->caller) & PSW_ADDR_INSN;
1472         rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %p  ",
1473                       area, time_spec.tv_sec, time_spec.tv_nsec / 1000, level,
1474                       except_str, entry->id.fields.cpuid, (void *) caller);
1475         return rc;
1476 }
1477
1478 /*
1479  * prints debug data sprintf-formated:
1480  * debug_sprinf_event/exception calls must be used together with this view
1481  */
1482
1483 #define DEBUG_SPRINTF_MAX_ARGS 10
1484
1485 static int
1486 debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view,
1487                         char *out_buf, debug_sprintf_entry_t *curr_event)
1488 {
1489         int num_longs, num_used_args = 0,i, rc = 0;
1490         int index[DEBUG_SPRINTF_MAX_ARGS];
1491
1492         /* count of longs fit into one entry */
1493         num_longs = id->buf_size /  sizeof(long);
1494
1495         if(num_longs < 1)
1496                 goto out; /* bufsize of entry too small */
1497         if(num_longs == 1) {
1498                 /* no args, we use only the string */
1499                 strcpy(out_buf, curr_event->string);
1500                 rc = strlen(curr_event->string);
1501                 goto out;
1502         }
1503
1504         /* number of arguments used for sprintf (without the format string) */
1505         num_used_args   = min(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1));
1506
1507         memset(index,0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int));
1508
1509         for(i = 0; i < num_used_args; i++)
1510                 index[i] = i;
1511
1512         rc =  sprintf(out_buf, curr_event->string, curr_event->args[index[0]],
1513                 curr_event->args[index[1]], curr_event->args[index[2]],
1514                 curr_event->args[index[3]], curr_event->args[index[4]],
1515                 curr_event->args[index[5]], curr_event->args[index[6]],
1516                 curr_event->args[index[7]], curr_event->args[index[8]],
1517                 curr_event->args[index[9]]);
1518
1519 out:
1520
1521         return rc;
1522 }
1523
1524 /*
1525  * clean up module
1526  */
1527 static void __exit debug_exit(void)
1528 {
1529         debugfs_remove(debug_debugfs_root_entry);
1530         unregister_sysctl_table(s390dbf_sysctl_header);
1531         return;
1532 }
1533
1534 /*
1535  * module definitions
1536  */
1537 postcore_initcall(debug_init);
1538 module_exit(debug_exit);
1539 MODULE_LICENSE("GPL");
1540
1541 EXPORT_SYMBOL(debug_register);
1542 EXPORT_SYMBOL(debug_unregister);
1543 EXPORT_SYMBOL(debug_set_level);
1544 EXPORT_SYMBOL(debug_stop_all);
1545 EXPORT_SYMBOL(debug_register_view);
1546 EXPORT_SYMBOL(debug_unregister_view);
1547 EXPORT_SYMBOL(debug_event_common);
1548 EXPORT_SYMBOL(debug_exception_common);
1549 EXPORT_SYMBOL(debug_hex_ascii_view);
1550 EXPORT_SYMBOL(debug_raw_view);
1551 EXPORT_SYMBOL(debug_dflt_header_fn);
1552 EXPORT_SYMBOL(debug_sprintf_view);
1553 EXPORT_SYMBOL(debug_sprintf_exception);
1554 EXPORT_SYMBOL(debug_sprintf_event);