arch/s390/kernel/debug.c

   1 /*
   2  *  arch/s390/kernel/debug.c
   3  *   S/390 debug facility
   4  *
   5  *    Copyright IBM Corp. 1999, 2012
   6  *
   7  *    Author(s): Michael Holzheu (holzheu@de.ibm.com),
   8  *               Holger Smolinski (Holger.Smolinski@de.ibm.com)
   9  *
  10  *    Bugreports to: <Linux390@de.ibm.com>
  11  */
  12
  13 #define KMSG_COMPONENT "s390dbf"
  14 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  15
  16 #include <linux/stddef.h>
  17 #include <linux/kernel.h>
  18 #include <linux/errno.h>
  19 #include <linux/slab.h>
  20 #include <linux/ctype.h>
  21 #include <linux/string.h>
  22 #include <linux/sysctl.h>
  23 #include <asm/uaccess.h>
  24 #include <linux/module.h>
  25 #include <linux/init.h>
  26 #include <linux/fs.h>
  27 #include <linux/debugfs.h>
  28
  29 #include <asm/debug.h>
  30
  31 #define DEBUG_PROLOG_ENTRY -1
  32
  33 #define ALL_AREAS 0 /* copy all debug areas */
  34 #define NO_AREAS  1 /* copy no debug areas */
  35
  36 /* typedefs */
  37
  38 typedef struct file_private_info {
  39         loff_t offset;                  /* offset of last read in file */
  40         int    act_area;                /* number of last formated area */
  41         int    act_page;                /* act page in given area */
  42         int    act_entry;               /* last formated entry (offset */
  43                                         /* relative to beginning of last */
  44                                         /* formated page) */
  45         size_t act_entry_offset;        /* up to this offset we copied */
  46                                         /* in last read the last formated */
  47                                         /* entry to userland */
  48         char   temp_buf[2048];          /* buffer for output */
  49         debug_info_t *debug_info_org;   /* original debug information */
  50         debug_info_t *debug_info_snap;  /* snapshot of debug information */
  51         struct debug_view *view;        /* used view of debug info */
  52 } file_private_info_t;
  53
  54 typedef struct
  55 {
  56         char *string;
  57         /*
  58          * This assumes that all args are converted into longs
  59          * on L/390 this is the case for all types of parameter
  60          * except of floats, and long long (32 bit)
  61          *
  62          */
  63         long args[0];
  64 } debug_sprintf_entry_t;
  65
  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(const char *name, int pages_per_area,
  77                         int nr_areas, int buf_size, umode_t mode);
  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 static struct debug_view debug_level_view = {
 125         "level",
 126         &debug_prolog_level_fn,
 127         NULL,
 128         NULL,
 129         &debug_input_level_fn,
 130         NULL
 131 };
 132
 133 static struct debug_view debug_pages_view = {
 134         "pages",
 135         &debug_prolog_pages_fn,
 136         NULL,
 137         NULL,
 138         &debug_input_pages_fn,
 139         NULL
 140 };
 141
 142 static struct debug_view debug_flush_view = {
 143         "flush",
 144         NULL,
 145         NULL,
 146         NULL,
 147         &debug_input_flush_fn,
 148         NULL
 149 };
 150
 151 struct debug_view debug_sprintf_view = {
 152         "sprintf",
 153         NULL,
 154         &debug_dflt_header_fn,
 155         (debug_format_proc_t*)&debug_sprintf_format_fn,
 156         NULL,
 157         NULL
 158 };
 159
 160 /* used by dump analysis tools to determine version of debug feature */
 161 static unsigned int __used 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 static DEFINE_MUTEX(debug_mutex);
 168
 169 static int initialized;
 170 static int debug_critical;
 171
 172 static const struct file_operations debug_file_ops = {
 173         .owner   = THIS_MODULE,
 174         .read    = debug_output,
 175         .write   = debug_input,
 176         .open    = debug_open,
 177         .release = debug_close,
 178         .llseek  = no_llseek,
 179 };
 180
 181 static struct dentry *debug_debugfs_root_entry;
 182
 183 /* functions */
 184
 185 /*
 186  * debug_areas_alloc
 187  * - Debug areas are implemented as a threedimensonal array:
 188  *   areas[areanumber][pagenumber][pageoffset]
 189  */
 190
 191 static debug_entry_t***
 192 debug_areas_alloc(int pages_per_area, int nr_areas)
 193 {
 194         debug_entry_t*** areas;
 195         int i,j;
 196
 197         areas = kmalloc(nr_areas *
 198                                         sizeof(debug_entry_t**),
 199                                         GFP_KERNEL);
 200         if (!areas)
 201                 goto fail_malloc_areas;
 202         for (i = 0; i < nr_areas; i++) {
 203                 areas[i] = kmalloc(pages_per_area *
 204                                 sizeof(debug_entry_t*),GFP_KERNEL);
 205                 if (!areas[i]) {
 206                         goto fail_malloc_areas2;
 207                 }
 208                 for(j = 0; j < pages_per_area; j++) {
 209                         areas[i][j] = kzalloc(PAGE_SIZE, GFP_KERNEL);
 210                         if(!areas[i][j]) {
 211                                 for(j--; j >=0 ; j--) {
 212                                         kfree(areas[i][j]);
 213                                 }
 214                                 kfree(areas[i]);
 215                                 goto fail_malloc_areas2;
 216                         }
 217                 }
 218         }
 219         return areas;
 220
 221 fail_malloc_areas2:
 222         for(i--; i >= 0; i--){
 223                 for(j=0; j < pages_per_area;j++){
 224                         kfree(areas[i][j]);
 225                 }
 226                 kfree(areas[i]);
 227         }
 228         kfree(areas);
 229 fail_malloc_areas:
 230         return NULL;
 231
 232 }
 233
 234
 235 /*
 236  * debug_info_alloc
 237  * - alloc new debug-info
 238  */
 239
 240 static debug_info_t*
 241 debug_info_alloc(const char *name, int pages_per_area, int nr_areas,
 242                  int buf_size, int level, int mode)
 243 {
 244         debug_info_t* rc;
 245
 246         /* alloc everything */
 247
 248         rc = kmalloc(sizeof(debug_info_t), GFP_KERNEL);
 249         if(!rc)
 250                 goto fail_malloc_rc;
 251         rc->active_entries = kcalloc(nr_areas, sizeof(int), GFP_KERNEL);
 252         if(!rc->active_entries)
 253                 goto fail_malloc_active_entries;
 254         rc->active_pages = kcalloc(nr_areas, sizeof(int), GFP_KERNEL);
 255         if(!rc->active_pages)
 256                 goto fail_malloc_active_pages;
 257         if((mode == ALL_AREAS) && (pages_per_area != 0)){
 258                 rc->areas = debug_areas_alloc(pages_per_area, nr_areas);
 259                 if(!rc->areas)
 260                         goto fail_malloc_areas;
 261         } else {
 262                 rc->areas = NULL;
 263         }
 264
 265         /* initialize members */
 266
 267         spin_lock_init(&rc->lock);
 268         rc->pages_per_area = pages_per_area;
 269         rc->nr_areas       = nr_areas;
 270         rc->active_area    = 0;
 271         rc->level          = level;
 272         rc->buf_size       = buf_size;
 273         rc->entry_size     = sizeof(debug_entry_t) + buf_size;
 274         strlcpy(rc->name, name, sizeof(rc->name));
 275         memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *));
 276         memset(rc->debugfs_entries, 0 ,DEBUG_MAX_VIEWS *
 277                 sizeof(struct dentry*));
 278         atomic_set(&(rc->ref_count), 0);
 279
 280         return rc;
 281
 282 fail_malloc_areas:
 283         kfree(rc->active_pages);
 284 fail_malloc_active_pages:
 285         kfree(rc->active_entries);
 286 fail_malloc_active_entries:
 287         kfree(rc);
 288 fail_malloc_rc:
 289         return NULL;
 290 }
 291
 292 /*
 293  * debug_areas_free
 294  * - free all debug areas
 295  */
 296
 297 static void
 298 debug_areas_free(debug_info_t* db_info)
 299 {
 300         int i,j;
 301
 302         if(!db_info->areas)
 303                 return;
 304         for (i = 0; i < db_info->nr_areas; i++) {
 305                 for(j = 0; j < db_info->pages_per_area; j++) {
 306                         kfree(db_info->areas[i][j]);
 307                 }
 308                 kfree(db_info->areas[i]);
 309         }
 310         kfree(db_info->areas);
 311         db_info->areas = NULL;
 312 }
 313
 314 /*
 315  * debug_info_free
 316  * - free memory debug-info
 317  */
 318
 319 static void
 320 debug_info_free(debug_info_t* db_info){
 321         debug_areas_free(db_info);
 322         kfree(db_info->active_entries);
 323         kfree(db_info->active_pages);
 324         kfree(db_info);
 325 }
 326
 327 /*
 328  * debug_info_create
 329  * - create new debug-info
 330  */
 331
 332 static debug_info_t*
 333 debug_info_create(const char *name, int pages_per_area, int nr_areas,
 334                   int buf_size, umode_t mode)
 335 {
 336         debug_info_t* rc;
 337
 338         rc = debug_info_alloc(name, pages_per_area, nr_areas, buf_size,
 339                                 DEBUG_DEFAULT_LEVEL, ALL_AREAS);
 340         if(!rc)
 341                 goto out;
 342
 343         rc->mode = mode & ~S_IFMT;
 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 (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 static 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         mutex_lock(&debug_mutex);
 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         mutex_unlock(&debug_mutex);
 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, rc = 0;
 608         file_private_info_t *p_info;
 609         debug_info_t *debug_info, *debug_info_snapshot;
 610
 611         mutex_lock(&debug_mutex);
 612         debug_info = file->f_path.dentry->d_inode->i_private;
 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_path.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 = kmalloc(sizeof(file_private_info_t),
 644                                                 GFP_KERNEL);
 645         if(!p_info){
 646                 debug_info_free(debug_info_snapshot);
 647                 rc = -ENOMEM;
 648                 goto out;
 649         }
 650         p_info->offset = 0;
 651         p_info->debug_info_snap = debug_info_snapshot;
 652         p_info->debug_info_org  = debug_info;
 653         p_info->view = debug_info->views[i];
 654         p_info->act_area = 0;
 655         p_info->act_page = 0;
 656         p_info->act_entry = DEBUG_PROLOG_ENTRY;
 657         p_info->act_entry_offset = 0;
 658         file->private_data = p_info;
 659         debug_info_get(debug_info);
 660         nonseekable_open(inode, file);
 661 out:
 662         mutex_unlock(&debug_mutex);
 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_mode:
 686  * - Creates and initializes debug area for the caller
 687  *   The mode parameter allows to specify access rights for the s390dbf files
 688  * - Returns handle for debug area
 689  */
 690
 691 debug_info_t *debug_register_mode(const char *name, int pages_per_area,
 692                                   int nr_areas, int buf_size, umode_t mode,
 693                                   uid_t uid, gid_t gid)
 694 {
 695         debug_info_t *rc = NULL;
 696
 697         /* Since debugfs currently does not support uid/gid other than root, */
 698         /* we do not allow gid/uid != 0 until we get support for that. */
 699         if ((uid != 0) || (gid != 0))
 700                 pr_warning("Root becomes the owner of all s390dbf files "
 701                            "in sysfs\n");
 702         BUG_ON(!initialized);
 703         mutex_lock(&debug_mutex);
 704
 705         /* create new debug_info */
 706
 707         rc = debug_info_create(name, pages_per_area, nr_areas, buf_size, mode);
 708         if(!rc)
 709                 goto out;
 710         debug_register_view(rc, &debug_level_view);
 711         debug_register_view(rc, &debug_flush_view);
 712         debug_register_view(rc, &debug_pages_view);
 713 out:
 714         if (!rc){
 715                 pr_err("Registering debug feature %s failed\n", name);
 716         }
 717         mutex_unlock(&debug_mutex);
 718         return rc;
 719 }
 720 EXPORT_SYMBOL(debug_register_mode);
 721
 722 /*
 723  * debug_register:
 724  * - creates and initializes debug area for the caller
 725  * - returns handle for debug area
 726  */
 727
 728 debug_info_t *debug_register(const char *name, int pages_per_area,
 729                              int nr_areas, int buf_size)
 730 {
 731         return debug_register_mode(name, pages_per_area, nr_areas, buf_size,
 732                                    S_IRUSR | S_IWUSR, 0, 0);
 733 }
 734
 735 /*
 736  * debug_unregister:
 737  * - give back debug area
 738  */
 739
 740 void
 741 debug_unregister(debug_info_t * id)
 742 {
 743         if (!id)
 744                 goto out;
 745         mutex_lock(&debug_mutex);
 746         debug_info_put(id);
 747         mutex_unlock(&debug_mutex);
 748
 749 out:
 750         return;
 751 }
 752
 753 /*
 754  * debug_set_size:
 755  * - set area size (number of pages) and number of areas
 756  */
 757 static int
 758 debug_set_size(debug_info_t* id, int nr_areas, int pages_per_area)
 759 {
 760         unsigned long flags;
 761         debug_entry_t *** new_areas;
 762         int rc=0;
 763
 764         if(!id || (nr_areas <= 0) || (pages_per_area < 0))
 765                 return -EINVAL;
 766         if(pages_per_area > 0){
 767                 new_areas = debug_areas_alloc(pages_per_area, nr_areas);
 768                 if(!new_areas) {
 769                         pr_info("Allocating memory for %i pages failed\n",
 770                                 pages_per_area);
 771                         rc = -ENOMEM;
 772                         goto out;
 773                 }
 774         } else {
 775                 new_areas = NULL;
 776         }
 777         spin_lock_irqsave(&id->lock,flags);
 778         debug_areas_free(id);
 779         id->areas = new_areas;
 780         id->nr_areas = nr_areas;
 781         id->pages_per_area = pages_per_area;
 782         id->active_area = 0;
 783         memset(id->active_entries,0,sizeof(int)*id->nr_areas);
 784         memset(id->active_pages, 0, sizeof(int)*id->nr_areas);
 785         spin_unlock_irqrestore(&id->lock,flags);
 786         pr_info("%s: set new size (%i pages)\n" ,id->name, pages_per_area);
 787 out:
 788         return rc;
 789 }
 790
 791 /*
 792  * debug_set_level:
 793  * - set actual debug level
 794  */
 795
 796 void
 797 debug_set_level(debug_info_t* id, int new_level)
 798 {
 799         unsigned long flags;
 800         if(!id)
 801                 return;
 802         spin_lock_irqsave(&id->lock,flags);
 803         if(new_level == DEBUG_OFF_LEVEL){
 804                 id->level = DEBUG_OFF_LEVEL;
 805                 pr_info("%s: switched off\n",id->name);
 806         } else if ((new_level > DEBUG_MAX_LEVEL) || (new_level < 0)) {
 807                 pr_info("%s: level %i is out of range (%i - %i)\n",
 808                         id->name, new_level, 0, DEBUG_MAX_LEVEL);
 809         } else {
 810                 id->level = new_level;
 811         }
 812         spin_unlock_irqrestore(&id->lock,flags);
 813 }
 814
 815
 816 /*
 817  * proceed_active_entry:
 818  * - set active entry to next in the ring buffer
 819  */
 820
 821 static inline void
 822 proceed_active_entry(debug_info_t * id)
 823 {
 824         if ((id->active_entries[id->active_area] += id->entry_size)
 825             > (PAGE_SIZE - id->entry_size)){
 826                 id->active_entries[id->active_area] = 0;
 827                 id->active_pages[id->active_area] =
 828                         (id->active_pages[id->active_area] + 1) %
 829                         id->pages_per_area;
 830         }
 831 }
 832
 833 /*
 834  * proceed_active_area:
 835  * - set active area to next in the ring buffer
 836  */
 837
 838 static inline void
 839 proceed_active_area(debug_info_t * id)
 840 {
 841         id->active_area++;
 842         id->active_area = id->active_area % id->nr_areas;
 843 }
 844
 845 /*
 846  * get_active_entry:
 847  */
 848
 849 static inline debug_entry_t*
 850 get_active_entry(debug_info_t * id)
 851 {
 852         return (debug_entry_t *) (((char *) id->areas[id->active_area]
 853                                         [id->active_pages[id->active_area]]) +
 854                                         id->active_entries[id->active_area]);
 855 }
 856
 857 /*
 858  * debug_finish_entry:
 859  * - set timestamp, caller address, cpu number etc.
 860  */
 861
 862 static inline void
 863 debug_finish_entry(debug_info_t * id, debug_entry_t* active, int level,
 864                         int exception)
 865 {
 866         active->id.stck = get_clock();
 867         active->id.fields.cpuid = smp_processor_id();
 868         active->caller = __builtin_return_address(0);
 869         active->id.fields.exception = exception;
 870         active->id.fields.level     = level;
 871         proceed_active_entry(id);
 872         if(exception)
 873                 proceed_active_area(id);
 874 }
 875
 876 static int debug_stoppable=1;
 877 static int debug_active=1;
 878
 879 #define CTL_S390DBF_STOPPABLE 5678
 880 #define CTL_S390DBF_ACTIVE 5679
 881
 882 /*
 883  * proc handler for the running debug_active sysctl
 884  * always allow read, allow write only if debug_stoppable is set or
 885  * if debug_active is already off
 886  */
 887 static int
 888 s390dbf_procactive(ctl_table *table, int write,
 889                      void __user *buffer, size_t *lenp, loff_t *ppos)
 890 {
 891         if (!write || debug_stoppable || !debug_active)
 892                 return proc_dointvec(table, write, buffer, lenp, ppos);
 893         else
 894                 return 0;
 895 }
 896
 897
 898 static struct ctl_table s390dbf_table[] = {
 899         {
 900                 .procname       = "debug_stoppable",
 901                 .data           = &debug_stoppable,
 902                 .maxlen         = sizeof(int),
 903                 .mode           = S_IRUGO | S_IWUSR,
 904                 .proc_handler   = proc_dointvec,
 905         },
 906          {
 907                 .procname       = "debug_active",
 908                 .data           = &debug_active,
 909                 .maxlen         = sizeof(int),
 910                 .mode           = S_IRUGO | S_IWUSR,
 911                 .proc_handler   = s390dbf_procactive,
 912         },
 913         { }
 914 };
 915
 916 static struct ctl_table s390dbf_dir_table[] = {
 917         {
 918                 .procname       = "s390dbf",
 919                 .maxlen         = 0,
 920                 .mode           = S_IRUGO | S_IXUGO,
 921                 .child          = s390dbf_table,
 922         },
 923         { }
 924 };
 925
 926 static struct ctl_table_header *s390dbf_sysctl_header;
 927
 928 void
 929 debug_stop_all(void)
 930 {
 931         if (debug_stoppable)
 932                 debug_active = 0;
 933 }
 934
 935
 936 void debug_set_critical(void)
 937 {
 938         debug_critical = 1;
 939 }
 940
 941 /*
 942  * debug_event_common:
 943  * - write debug entry with given size
 944  */
 945
 946 debug_entry_t*
 947 debug_event_common(debug_info_t * id, int level, const void *buf, int len)
 948 {
 949         unsigned long flags;
 950         debug_entry_t *active;
 951
 952         if (!debug_active || !id->areas)
 953                 return NULL;
 954         if (debug_critical) {
 955                 if (!spin_trylock_irqsave(&id->lock, flags))
 956                         return NULL;
 957         } else
 958                 spin_lock_irqsave(&id->lock, flags);
 959         active = get_active_entry(id);
 960         memset(DEBUG_DATA(active), 0, id->buf_size);
 961         memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
 962         debug_finish_entry(id, active, level, 0);
 963         spin_unlock_irqrestore(&id->lock, flags);
 964
 965         return active;
 966 }
 967
 968 /*
 969  * debug_exception_common:
 970  * - write debug entry with given size and switch to next debug area
 971  */
 972
 973 debug_entry_t
 974 *debug_exception_common(debug_info_t * id, int level, const void *buf, int len)
 975 {
 976         unsigned long flags;
 977         debug_entry_t *active;
 978
 979         if (!debug_active || !id->areas)
 980                 return NULL;
 981         if (debug_critical) {
 982                 if (!spin_trylock_irqsave(&id->lock, flags))
 983                         return NULL;
 984         } else
 985                 spin_lock_irqsave(&id->lock, flags);
 986         active = get_active_entry(id);
 987         memset(DEBUG_DATA(active), 0, id->buf_size);
 988         memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
 989         debug_finish_entry(id, active, level, 1);
 990         spin_unlock_irqrestore(&id->lock, flags);
 991
 992         return active;
 993 }
 994
 995 /*
 996  * counts arguments in format string for sprintf view
 997  */
 998
 999 static inline int
1000 debug_count_numargs(char *string)
1001 {
1002         int numargs=0;
1003
1004         while(*string) {
1005                 if(*string++=='%')
1006                         numargs++;
1007         }
1008         return(numargs);
1009 }
1010
1011 /*
1012  * debug_sprintf_event:
1013  */
1014
1015 debug_entry_t*
1016 debug_sprintf_event(debug_info_t* id, int level,char *string,...)
1017 {
1018         va_list   ap;
1019         int numargs,idx;
1020         unsigned long flags;
1021         debug_sprintf_entry_t *curr_event;
1022         debug_entry_t *active;
1023
1024         if((!id) || (level > id->level))
1025                 return NULL;
1026         if (!debug_active || !id->areas)
1027                 return NULL;
1028         numargs=debug_count_numargs(string);
1029
1030         if (debug_critical) {
1031                 if (!spin_trylock_irqsave(&id->lock, flags))
1032                         return NULL;
1033         } else
1034                 spin_lock_irqsave(&id->lock, flags);
1035         active = get_active_entry(id);
1036         curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active);
1037         va_start(ap,string);
1038         curr_event->string=string;
1039         for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
1040                 curr_event->args[idx]=va_arg(ap,long);
1041         va_end(ap);
1042         debug_finish_entry(id, active, level, 0);
1043         spin_unlock_irqrestore(&id->lock, flags);
1044
1045         return active;
1046 }
1047
1048 /*
1049  * debug_sprintf_exception:
1050  */
1051
1052 debug_entry_t*
1053 debug_sprintf_exception(debug_info_t* id, int level,char *string,...)
1054 {
1055         va_list   ap;
1056         int numargs,idx;
1057         unsigned long flags;
1058         debug_sprintf_entry_t *curr_event;
1059         debug_entry_t *active;
1060
1061         if((!id) || (level > id->level))
1062                 return NULL;
1063         if (!debug_active || !id->areas)
1064                 return NULL;
1065
1066         numargs=debug_count_numargs(string);
1067
1068         if (debug_critical) {
1069                 if (!spin_trylock_irqsave(&id->lock, flags))
1070                         return NULL;
1071         } else
1072                 spin_lock_irqsave(&id->lock, flags);
1073         active = get_active_entry(id);
1074         curr_event=(debug_sprintf_entry_t *)DEBUG_DATA(active);
1075         va_start(ap,string);
1076         curr_event->string=string;
1077         for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
1078                 curr_event->args[idx]=va_arg(ap,long);
1079         va_end(ap);
1080         debug_finish_entry(id, active, level, 1);
1081         spin_unlock_irqrestore(&id->lock, flags);
1082
1083         return active;
1084 }
1085
1086 /*
1087  * debug_init:
1088  * - is called exactly once to initialize the debug feature
1089  */
1090
1091 static int
1092 __init debug_init(void)
1093 {
1094         int rc = 0;
1095
1096         s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table);
1097         mutex_lock(&debug_mutex);
1098         debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT,NULL);
1099         initialized = 1;
1100         mutex_unlock(&debug_mutex);
1101
1102         return rc;
1103 }
1104
1105 /*
1106  * debug_register_view:
1107  */
1108
1109 int
1110 debug_register_view(debug_info_t * id, struct debug_view *view)
1111 {
1112         int rc = 0;
1113         int i;
1114         unsigned long flags;
1115         umode_t mode;
1116         struct dentry *pde;
1117
1118         if (!id)
1119                 goto out;
1120         mode = (id->mode | S_IFREG) & ~S_IXUGO;
1121         if (!(view->prolog_proc || view->format_proc || view->header_proc))
1122                 mode &= ~(S_IRUSR | S_IRGRP | S_IROTH);
1123         if (!view->input_proc)
1124                 mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);
1125         pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry,
1126                                 id , &debug_file_ops);
1127         if (!pde){
1128                 pr_err("Registering view %s/%s failed due to out of "
1129                        "memory\n", id->name,view->name);
1130                 rc = -1;
1131                 goto out;
1132         }
1133         spin_lock_irqsave(&id->lock, flags);
1134         for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1135                 if (!id->views[i])
1136                         break;
1137         }
1138         if (i == DEBUG_MAX_VIEWS) {
1139                 pr_err("Registering view %s/%s would exceed the maximum "
1140                        "number of views %i\n", id->name, view->name, i);
1141                 debugfs_remove(pde);
1142                 rc = -1;
1143         } else {
1144                 id->views[i] = view;
1145                 id->debugfs_entries[i] = pde;
1146         }
1147         spin_unlock_irqrestore(&id->lock, flags);
1148 out:
1149         return rc;
1150 }
1151
1152 /*
1153  * debug_unregister_view:
1154  */
1155
1156 int
1157 debug_unregister_view(debug_info_t * id, struct debug_view *view)
1158 {
1159         int rc = 0;
1160         int i;
1161         unsigned long flags;
1162
1163         if (!id)
1164                 goto out;
1165         spin_lock_irqsave(&id->lock, flags);
1166         for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1167                 if (id->views[i] == view)
1168                         break;
1169         }
1170         if (i == DEBUG_MAX_VIEWS)
1171                 rc = -1;
1172         else {
1173                 debugfs_remove(id->debugfs_entries[i]);
1174                 id->views[i] = NULL;
1175         }
1176         spin_unlock_irqrestore(&id->lock, flags);
1177 out:
1178         return rc;
1179 }
1180
1181 static inline char *
1182 debug_get_user_string(const char __user *user_buf, size_t user_len)
1183 {
1184         char* buffer;
1185
1186         buffer = kmalloc(user_len + 1, GFP_KERNEL);
1187         if (!buffer)
1188                 return ERR_PTR(-ENOMEM);
1189         if (copy_from_user(buffer, user_buf, user_len) != 0) {
1190                 kfree(buffer);
1191                 return ERR_PTR(-EFAULT);
1192         }
1193         /* got the string, now strip linefeed. */
1194         if (buffer[user_len - 1] == '\n')
1195                 buffer[user_len - 1] = 0;
1196         else
1197                 buffer[user_len] = 0;
1198         return buffer;
1199 }
1200
1201 static inline int
1202 debug_get_uint(char *buf)
1203 {
1204         int rc;
1205
1206         buf = skip_spaces(buf);
1207         rc = simple_strtoul(buf, &buf, 10);
1208         if(*buf){
1209                 rc = -EINVAL;
1210         }
1211         return rc;
1212 }
1213
1214 /*
1215  * functions for debug-views
1216  ***********************************
1217 */
1218
1219 /*
1220  * prints out actual debug level
1221  */
1222
1223 static int
1224 debug_prolog_pages_fn(debug_info_t * id,
1225                                  struct debug_view *view, char *out_buf)
1226 {
1227         return sprintf(out_buf, "%i\n", id->pages_per_area);
1228 }
1229
1230 /*
1231  * reads new size (number of pages per debug area)
1232  */
1233
1234 static int
1235 debug_input_pages_fn(debug_info_t * id, struct debug_view *view,
1236                         struct file *file, const char __user *user_buf,
1237                         size_t user_len, loff_t * offset)
1238 {
1239         char *str;
1240         int rc,new_pages;
1241
1242         if (user_len > 0x10000)
1243                 user_len = 0x10000;
1244         if (*offset != 0){
1245                 rc = -EPIPE;
1246                 goto out;
1247         }
1248         str = debug_get_user_string(user_buf,user_len);
1249         if(IS_ERR(str)){
1250                 rc = PTR_ERR(str);
1251                 goto out;
1252         }
1253         new_pages = debug_get_uint(str);
1254         if(new_pages < 0){
1255                 rc = -EINVAL;
1256                 goto free_str;
1257         }
1258         rc = debug_set_size(id,id->nr_areas, new_pages);
1259         if(rc != 0){
1260                 rc = -EINVAL;
1261                 goto free_str;
1262         }
1263         rc = user_len;
1264 free_str:
1265         kfree(str);
1266 out:
1267         *offset += user_len;
1268         return rc;              /* number of input characters */
1269 }
1270
1271 /*
1272  * prints out actual debug level
1273  */
1274
1275 static int
1276 debug_prolog_level_fn(debug_info_t * id, struct debug_view *view, char *out_buf)
1277 {
1278         int rc = 0;
1279
1280         if(id->level == DEBUG_OFF_LEVEL) {
1281                 rc = sprintf(out_buf,"-\n");
1282         }
1283         else {
1284                 rc = sprintf(out_buf, "%i\n", id->level);
1285         }
1286         return rc;
1287 }
1288
1289 /*
1290  * reads new debug level
1291  */
1292
1293 static int
1294 debug_input_level_fn(debug_info_t * id, struct debug_view *view,
1295                         struct file *file, const char __user *user_buf,
1296                         size_t user_len, loff_t * offset)
1297 {
1298         char *str;
1299         int rc,new_level;
1300
1301         if (user_len > 0x10000)
1302                 user_len = 0x10000;
1303         if (*offset != 0){
1304                 rc = -EPIPE;
1305                 goto out;
1306         }
1307         str = debug_get_user_string(user_buf,user_len);
1308         if(IS_ERR(str)){
1309                 rc = PTR_ERR(str);
1310                 goto out;
1311         }
1312         if(str[0] == '-'){
1313                 debug_set_level(id, DEBUG_OFF_LEVEL);
1314                 rc = user_len;
1315                 goto free_str;
1316         } else {
1317                 new_level = debug_get_uint(str);
1318         }
1319         if(new_level < 0) {
1320                 pr_warning("%s is not a valid level for a debug "
1321                            "feature\n", str);
1322                 rc = -EINVAL;
1323         } else {
1324                 debug_set_level(id, new_level);
1325                 rc = user_len;
1326         }
1327 free_str:
1328         kfree(str);
1329 out:
1330         *offset += user_len;
1331         return rc;              /* number of input characters */
1332 }
1333
1334
1335 /*
1336  * flushes debug areas
1337  */
1338
1339 static void debug_flush(debug_info_t* id, int area)
1340 {
1341         unsigned long flags;
1342         int i,j;
1343
1344         if(!id || !id->areas)
1345                 return;
1346         spin_lock_irqsave(&id->lock,flags);
1347         if(area == DEBUG_FLUSH_ALL){
1348                 id->active_area = 0;
1349                 memset(id->active_entries, 0, id->nr_areas * sizeof(int));
1350                 for (i = 0; i < id->nr_areas; i++) {
1351                         id->active_pages[i] = 0;
1352                         for(j = 0; j < id->pages_per_area; j++) {
1353                                 memset(id->areas[i][j], 0, PAGE_SIZE);
1354                         }
1355                 }
1356         } else if(area >= 0 && area < id->nr_areas) {
1357                 id->active_entries[area] = 0;
1358                 id->active_pages[area] = 0;
1359                 for(i = 0; i < id->pages_per_area; i++) {
1360                         memset(id->areas[area][i],0,PAGE_SIZE);
1361                 }
1362         }
1363         spin_unlock_irqrestore(&id->lock,flags);
1364 }
1365
1366 /*
1367  * view function: flushes debug areas
1368  */
1369
1370 static int
1371 debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
1372                         struct file *file, const char __user *user_buf,
1373                         size_t user_len, loff_t * offset)
1374 {
1375         char input_buf[1];
1376         int rc = user_len;
1377
1378         if (user_len > 0x10000)
1379                 user_len = 0x10000;
1380         if (*offset != 0){
1381                 rc = -EPIPE;
1382                 goto out;
1383         }
1384         if (copy_from_user(input_buf, user_buf, 1)){
1385                 rc = -EFAULT;
1386                 goto out;
1387         }
1388         if(input_buf[0] == '-') {
1389                 debug_flush(id, DEBUG_FLUSH_ALL);
1390                 goto out;
1391         }
1392         if (isdigit(input_buf[0])) {
1393                 int area = ((int) input_buf[0] - (int) '0');
1394                 debug_flush(id, area);
1395                 goto out;
1396         }
1397
1398         pr_info("Flushing debug data failed because %c is not a valid "
1399                  "area\n", input_buf[0]);
1400
1401 out:
1402         *offset += user_len;
1403         return rc;              /* number of input characters */
1404 }
1405
1406 /*
1407  * prints debug header in raw format
1408  */
1409
1410 static int
1411 debug_raw_header_fn(debug_info_t * id, struct debug_view *view,
1412                         int area, debug_entry_t * entry, char *out_buf)
1413 {
1414         int rc;
1415
1416         rc = sizeof(debug_entry_t);
1417         memcpy(out_buf,entry,sizeof(debug_entry_t));
1418         return rc;
1419 }
1420
1421 /*
1422  * prints debug data in raw format
1423  */
1424
1425 static int
1426 debug_raw_format_fn(debug_info_t * id, struct debug_view *view,
1427                                char *out_buf, const char *in_buf)
1428 {
1429         int rc;
1430
1431         rc = id->buf_size;
1432         memcpy(out_buf, in_buf, id->buf_size);
1433         return rc;
1434 }
1435
1436 /*
1437  * prints debug data in hex/ascii format
1438  */
1439
1440 static int
1441 debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
1442                           char *out_buf, const char *in_buf)
1443 {
1444         int i, rc = 0;
1445
1446         for (i = 0; i < id->buf_size; i++) {
1447                 rc += sprintf(out_buf + rc, "%02x ",
1448                               ((unsigned char *) in_buf)[i]);
1449         }
1450         rc += sprintf(out_buf + rc, "| ");
1451         for (i = 0; i < id->buf_size; i++) {
1452                 unsigned char c = in_buf[i];
1453                 if (isascii(c) && isprint(c))
1454                         rc += sprintf(out_buf + rc, "%c", c);
1455                 else
1456                         rc += sprintf(out_buf + rc, ".");
1457         }
1458         rc += sprintf(out_buf + rc, "\n");
1459         return rc;
1460 }
1461
1462 /*
1463  * prints header for debug entry
1464  */
1465
1466 int
1467 debug_dflt_header_fn(debug_info_t * id, struct debug_view *view,
1468                          int area, debug_entry_t * entry, char *out_buf)
1469 {
1470         struct timespec time_spec;
1471         char *except_str;
1472         unsigned long caller;
1473         int rc = 0;
1474         unsigned int level;
1475
1476         level = entry->id.fields.level;
1477         stck_to_timespec(entry->id.stck, &time_spec);
1478
1479         if (entry->id.fields.exception)
1480                 except_str = "*";
1481         else
1482                 except_str = "-";
1483         caller = ((unsigned long) entry->caller) & PSW_ADDR_INSN;
1484         rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %p  ",
1485                       area, time_spec.tv_sec, time_spec.tv_nsec / 1000, level,
1486                       except_str, entry->id.fields.cpuid, (void *) caller);
1487         return rc;
1488 }
1489
1490 /*
1491  * prints debug data sprintf-formated:
1492  * debug_sprinf_event/exception calls must be used together with this view
1493  */
1494
1495 #define DEBUG_SPRINTF_MAX_ARGS 10
1496
1497 static int
1498 debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view,
1499                         char *out_buf, debug_sprintf_entry_t *curr_event)
1500 {
1501         int num_longs, num_used_args = 0,i, rc = 0;
1502         int index[DEBUG_SPRINTF_MAX_ARGS];
1503
1504         /* count of longs fit into one entry */
1505         num_longs = id->buf_size /  sizeof(long);
1506
1507         if(num_longs < 1)
1508                 goto out; /* bufsize of entry too small */
1509         if(num_longs == 1) {
1510                 /* no args, we use only the string */
1511                 strcpy(out_buf, curr_event->string);
1512                 rc = strlen(curr_event->string);
1513                 goto out;
1514         }
1515
1516         /* number of arguments used for sprintf (without the format string) */
1517         num_used_args   = min(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1));
1518
1519         memset(index,0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int));
1520
1521         for(i = 0; i < num_used_args; i++)
1522                 index[i] = i;
1523
1524         rc =  sprintf(out_buf, curr_event->string, curr_event->args[index[0]],
1525                 curr_event->args[index[1]], curr_event->args[index[2]],
1526                 curr_event->args[index[3]], curr_event->args[index[4]],
1527                 curr_event->args[index[5]], curr_event->args[index[6]],
1528                 curr_event->args[index[7]], curr_event->args[index[8]],
1529                 curr_event->args[index[9]]);
1530
1531 out:
1532
1533         return rc;
1534 }
1535
1536 /*
1537  * clean up module
1538  */
1539 static void __exit debug_exit(void)
1540 {
1541         debugfs_remove(debug_debugfs_root_entry);
1542         unregister_sysctl_table(s390dbf_sysctl_header);
1543         return;
1544 }
1545
1546 /*
1547  * module definitions
1548  */
1549 postcore_initcall(debug_init);
1550 module_exit(debug_exit);
1551 MODULE_LICENSE("GPL");
1552
1553 EXPORT_SYMBOL(debug_register);
1554 EXPORT_SYMBOL(debug_unregister);
1555 EXPORT_SYMBOL(debug_set_level);
1556 EXPORT_SYMBOL(debug_stop_all);
1557 EXPORT_SYMBOL(debug_register_view);
1558 EXPORT_SYMBOL(debug_unregister_view);
1559 EXPORT_SYMBOL(debug_event_common);
1560 EXPORT_SYMBOL(debug_exception_common);
1561 EXPORT_SYMBOL(debug_hex_ascii_view);
1562 EXPORT_SYMBOL(debug_raw_view);
1563 EXPORT_SYMBOL(debug_dflt_header_fn);
1564 EXPORT_SYMBOL(debug_sprintf_view);
1565 EXPORT_SYMBOL(debug_sprintf_exception);
1566 EXPORT_SYMBOL(debug_sprintf_event);