1/*
   2 *   S/390 debug facility
   3 *
   4 *    Copyright IBM Corp. 1999, 2012
   5 *
   6 *    Author(s): Michael Holzheu (holzheu@de.ibm.com),
   7 *               Holger Smolinski (Holger.Smolinski@de.ibm.com)
   8 *
   9 *    Bugreports to: <Linux390@de.ibm.com>
  10 */
  11
  12#define KMSG_COMPONENT "s390dbf"
  13#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  14
  15#include <linux/stddef.h>
  16#include <linux/kernel.h>
  17#include <linux/errno.h>
  18#include <linux/slab.h>
  19#include <linux/ctype.h>
  20#include <linux/string.h>
  21#include <linux/sysctl.h>
  22#include <asm/uaccess.h>
  23#include <linux/module.h>
  24#include <linux/init.h>
  25#include <linux/fs.h>
  26#include <linux/debugfs.h>
  27
  28#include <asm/debug.h>
  29
  30#define DEBUG_PROLOG_ENTRY -1
  31
  32#define ALL_AREAS 0 /* copy all debug areas */
  33#define NO_AREAS  1 /* copy no debug areas */
  34
  35/* typedefs */
  36
  37typedef struct file_private_info {
  38	loff_t offset;			/* offset of last read in file */
  39	int    act_area;                /* number of last formated area */
  40	int    act_page;                /* act page in given area */
  41	int    act_entry;               /* last formated entry (offset */
  42                                        /* relative to beginning of last */
  43                                        /* formated page) */
  44	size_t act_entry_offset;        /* up to this offset we copied */
  45					/* in last read the last formated */
  46					/* entry to userland */
  47	char   temp_buf[2048];		/* buffer for output */
  48	debug_info_t *debug_info_org;   /* original debug information */
  49	debug_info_t *debug_info_snap;	/* snapshot of debug information */
  50	struct debug_view *view;	/* used view of debug info */
  51} file_private_info_t;
  52
  53typedef struct
  54{
  55	char *string;
  56	/* 
  57	 * This assumes that all args are converted into longs 
  58	 * on L/390 this is the case for all types of parameter 
  59	 * except of floats, and long long (32 bit) 
  60	 *
  61	 */
  62	long args[0];
  63} debug_sprintf_entry_t;
  64
  65
  66/* internal function prototyes */
  67
  68static int debug_init(void);
  69static ssize_t debug_output(struct file *file, char __user *user_buf,
  70			size_t user_len, loff_t * offset);
  71static ssize_t debug_input(struct file *file, const char __user *user_buf,
  72			size_t user_len, loff_t * offset);
  73static int debug_open(struct inode *inode, struct file *file);
  74static int debug_close(struct inode *inode, struct file *file);
  75static debug_info_t *debug_info_create(const char *name, int pages_per_area,
  76			int nr_areas, int buf_size, umode_t mode);
  77static void debug_info_get(debug_info_t *);
  78static void debug_info_put(debug_info_t *);
  79static int debug_prolog_level_fn(debug_info_t * id,
  80			struct debug_view *view, char *out_buf);
  81static int debug_input_level_fn(debug_info_t * id, struct debug_view *view,
  82			struct file *file, const char __user *user_buf,
  83			size_t user_buf_size, loff_t * offset);
  84static int debug_prolog_pages_fn(debug_info_t * id,
  85			struct debug_view *view, char *out_buf);
  86static int debug_input_pages_fn(debug_info_t * id, struct debug_view *view,
  87			struct file *file, const char __user *user_buf,
  88			size_t user_buf_size, loff_t * offset);
  89static int debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
  90			struct file *file, const char __user *user_buf,
  91			size_t user_buf_size, loff_t * offset);
  92static int debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
  93			char *out_buf, const char *in_buf);
  94static int debug_raw_format_fn(debug_info_t * id,
  95			struct debug_view *view, char *out_buf,
  96			const char *in_buf);
  97static int debug_raw_header_fn(debug_info_t * id, struct debug_view *view,
  98			int area, debug_entry_t * entry, char *out_buf);
  99
 100static int debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view,
 101			char *out_buf, debug_sprintf_entry_t *curr_event);
 102
 103/* globals */
 104
 105struct debug_view debug_raw_view = {
 106	"raw",
 107	NULL,
 108	&debug_raw_header_fn,
 109	&debug_raw_format_fn,
 110	NULL,
 111	NULL
 112};
 113EXPORT_SYMBOL(debug_raw_view);
 114
 115struct 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};
 123EXPORT_SYMBOL(debug_hex_ascii_view);
 124
 125static struct debug_view debug_level_view = {
 126	"level",
 127	&debug_prolog_level_fn,
 128	NULL,
 129	NULL,
 130	&debug_input_level_fn,
 131	NULL
 132};
 133
 134static struct debug_view debug_pages_view = {
 135	"pages",
 136	&debug_prolog_pages_fn,
 137	NULL,
 138	NULL,
 139	&debug_input_pages_fn,
 140	NULL
 141};
 142
 143static struct debug_view debug_flush_view = {
 144        "flush",
 145        NULL,
 146        NULL,
 147        NULL,
 148        &debug_input_flush_fn,
 149        NULL
 150};
 151
 152struct debug_view debug_sprintf_view = {
 153	"sprintf",
 154	NULL,
 155	&debug_dflt_header_fn,
 156	(debug_format_proc_t*)&debug_sprintf_format_fn,
 157	NULL,
 158	NULL
 159};
 160EXPORT_SYMBOL(debug_sprintf_view);
 161
 162/* used by dump analysis tools to determine version of debug feature */
 163static unsigned int __used debug_feature_version = __DEBUG_FEATURE_VERSION;
 164
 165/* static globals */
 166
 167static debug_info_t *debug_area_first = NULL;
 168static debug_info_t *debug_area_last = NULL;
 169static DEFINE_MUTEX(debug_mutex);
 170
 171static int initialized;
 172static int debug_critical;
 173
 174static const struct file_operations debug_file_ops = {
 175	.owner   = THIS_MODULE,
 176	.read    = debug_output,
 177	.write   = debug_input,
 178	.open    = debug_open,
 179	.release = debug_close,
 180	.llseek  = no_llseek,
 181};
 182
 183static struct dentry *debug_debugfs_root_entry;
 184
 185/* functions */
 186
 187/*
 188 * debug_areas_alloc
 189 * - Debug areas are implemented as a threedimensonal array:
 190 *   areas[areanumber][pagenumber][pageoffset]
 191 */
 192
 193static debug_entry_t***
 194debug_areas_alloc(int pages_per_area, int nr_areas)
 195{
 196	debug_entry_t*** areas;
 197	int i,j;
 198
 199	areas = kmalloc(nr_areas *
 200					sizeof(debug_entry_t**),
 201					GFP_KERNEL);
 202	if (!areas)
 203		goto fail_malloc_areas;
 204	for (i = 0; i < nr_areas; i++) {
 205		areas[i] = kmalloc(pages_per_area *
 206				sizeof(debug_entry_t*),GFP_KERNEL);
 207		if (!areas[i]) {
 208			goto fail_malloc_areas2;
 209		}
 210		for(j = 0; j < pages_per_area; j++) {
 211			areas[i][j] = kzalloc(PAGE_SIZE, GFP_KERNEL);
 212			if(!areas[i][j]) {
 213				for(j--; j >=0 ; j--) {
 214					kfree(areas[i][j]);
 215				}
 216				kfree(areas[i]);
 217				goto fail_malloc_areas2;
 218			}
 219		}
 220	}
 221	return areas;
 222
 223fail_malloc_areas2:
 224	for(i--; i >= 0; i--){
 225		for(j=0; j < pages_per_area;j++){
 226			kfree(areas[i][j]);
 227		}
 228		kfree(areas[i]);
 229	}
 230	kfree(areas);
 231fail_malloc_areas:
 232	return NULL;
 233
 234}
 235
 236
 237/*
 238 * debug_info_alloc
 239 * - alloc new debug-info
 240 */
 241
 242static debug_info_t*
 243debug_info_alloc(const char *name, int pages_per_area, int nr_areas,
 244		 int buf_size, int level, int mode)
 245{
 246	debug_info_t* rc;
 247
 248	/* alloc everything */
 249
 250	rc = kmalloc(sizeof(debug_info_t), GFP_KERNEL);
 251	if(!rc)
 252		goto fail_malloc_rc;
 253	rc->active_entries = kcalloc(nr_areas, sizeof(int), GFP_KERNEL);
 254	if(!rc->active_entries)
 255		goto fail_malloc_active_entries;
 256	rc->active_pages = kcalloc(nr_areas, sizeof(int), GFP_KERNEL);
 257	if(!rc->active_pages)
 258		goto fail_malloc_active_pages;
 259	if((mode == ALL_AREAS) && (pages_per_area != 0)){
 260		rc->areas = debug_areas_alloc(pages_per_area, nr_areas);
 261		if(!rc->areas)
 262			goto fail_malloc_areas;
 263	} else {
 264		rc->areas = NULL;
 265	}
 266
 267	/* initialize members */
 268
 269	spin_lock_init(&rc->lock);
 270	rc->pages_per_area = pages_per_area;
 271	rc->nr_areas       = nr_areas;
 272	rc->active_area    = 0;
 273	rc->level          = level;
 274	rc->buf_size       = buf_size;
 275	rc->entry_size     = sizeof(debug_entry_t) + buf_size;
 276	strlcpy(rc->name, name, sizeof(rc->name));
 277	memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *));
 278	memset(rc->debugfs_entries, 0 ,DEBUG_MAX_VIEWS *
 279		sizeof(struct dentry*));
 280	atomic_set(&(rc->ref_count), 0);
 281
 282	return rc;
 283
 284fail_malloc_areas:
 285	kfree(rc->active_pages);
 286fail_malloc_active_pages:
 287	kfree(rc->active_entries);
 288fail_malloc_active_entries:
 289	kfree(rc);
 290fail_malloc_rc:
 291	return NULL;
 292}
 293
 294/*
 295 * debug_areas_free
 296 * - free all debug areas
 297 */
 298
 299static void
 300debug_areas_free(debug_info_t* db_info)
 301{
 302	int i,j;
 303
 304	if(!db_info->areas)
 305		return;
 306	for (i = 0; i < db_info->nr_areas; i++) {
 307		for(j = 0; j < db_info->pages_per_area; j++) {
 308			kfree(db_info->areas[i][j]);
 309		}
 310		kfree(db_info->areas[i]);
 311	}
 312	kfree(db_info->areas);
 313	db_info->areas = NULL;
 314}
 315
 316/*
 317 * debug_info_free
 318 * - free memory debug-info
 319 */
 320
 321static void
 322debug_info_free(debug_info_t* db_info){
 323	debug_areas_free(db_info);
 324	kfree(db_info->active_entries);
 325	kfree(db_info->active_pages);
 326	kfree(db_info);
 327}
 328
 329/*
 330 * debug_info_create
 331 * - create new debug-info
 332 */
 333
 334static debug_info_t*
 335debug_info_create(const char *name, int pages_per_area, int nr_areas,
 336		  int buf_size, umode_t mode)
 337{
 338	debug_info_t* rc;
 339
 340        rc = debug_info_alloc(name, pages_per_area, nr_areas, buf_size,
 341				DEBUG_DEFAULT_LEVEL, ALL_AREAS);
 342        if(!rc) 
 343		goto out;
 344
 345	rc->mode = mode & ~S_IFMT;
 346
 347	/* create root directory */
 348        rc->debugfs_root_entry = debugfs_create_dir(rc->name,
 349					debug_debugfs_root_entry);
 350
 351	/* append new element to linked list */
 352        if (!debug_area_first) {
 353                /* first element in list */
 354                debug_area_first = rc;
 355                rc->prev = NULL;
 356        } else {
 357                /* append element to end of list */
 358                debug_area_last->next = rc;
 359                rc->prev = debug_area_last;
 360        }
 361        debug_area_last = rc;
 362        rc->next = NULL;
 363
 364	debug_info_get(rc);
 365out:
 366	return rc;
 367}
 368
 369/*
 370 * debug_info_copy
 371 * - copy debug-info
 372 */
 373
 374static debug_info_t*
 375debug_info_copy(debug_info_t* in, int mode)
 376{
 377        int i,j;
 378        debug_info_t* rc;
 379        unsigned long flags;
 380
 381	/* get a consistent copy of the debug areas */
 382	do {
 383		rc = debug_info_alloc(in->name, in->pages_per_area,
 384			in->nr_areas, in->buf_size, in->level, mode);
 385		spin_lock_irqsave(&in->lock, flags);
 386		if(!rc)
 387			goto out;
 388		/* has something changed in the meantime ? */
 389		if((rc->pages_per_area == in->pages_per_area) &&
 390		   (rc->nr_areas == in->nr_areas)) {
 391			break;
 392		}
 393		spin_unlock_irqrestore(&in->lock, flags);
 394		debug_info_free(rc);
 395	} while (1);
 396
 397	if (mode == NO_AREAS)
 398                goto out;
 399
 400        for(i = 0; i < in->nr_areas; i++){
 401		for(j = 0; j < in->pages_per_area; j++) {
 402			memcpy(rc->areas[i][j], in->areas[i][j],PAGE_SIZE);
 403		}
 404        }
 405out:
 406        spin_unlock_irqrestore(&in->lock, flags);
 407        return rc;
 408}
 409
 410/*
 411 * debug_info_get
 412 * - increments reference count for debug-info
 413 */
 414
 415static void
 416debug_info_get(debug_info_t * db_info)
 417{
 418	if (db_info)
 419		atomic_inc(&db_info->ref_count);
 420}
 421
 422/*
 423 * debug_info_put:
 424 * - decreases reference count for debug-info and frees it if necessary
 425 */
 426
 427static void
 428debug_info_put(debug_info_t *db_info)
 429{
 430	int i;
 431
 432	if (!db_info)
 433		return;
 434	if (atomic_dec_and_test(&db_info->ref_count)) {
 435		for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
 436			if (!db_info->views[i])
 437				continue;
 438			debugfs_remove(db_info->debugfs_entries[i]);
 439		}
 440		debugfs_remove(db_info->debugfs_root_entry);
 441		if(db_info == debug_area_first)
 442			debug_area_first = db_info->next;
 443		if(db_info == debug_area_last)
 444			debug_area_last = db_info->prev;
 445		if(db_info->prev) db_info->prev->next = db_info->next;
 446		if(db_info->next) db_info->next->prev = db_info->prev;
 447		debug_info_free(db_info);
 448	}
 449}
 450
 451/*
 452 * debug_format_entry:
 453 * - format one debug entry and return size of formated data
 454 */
 455
 456static int
 457debug_format_entry(file_private_info_t *p_info)
 458{
 459	debug_info_t *id_snap   = p_info->debug_info_snap;
 460	struct debug_view *view = p_info->view;
 461	debug_entry_t *act_entry;
 462	size_t len = 0;
 463	if(p_info->act_entry == DEBUG_PROLOG_ENTRY){
 464		/* print prolog */
 465        	if (view->prolog_proc)
 466                	len += view->prolog_proc(id_snap,view,p_info->temp_buf);
 467		goto out;
 468	}
 469	if (!id_snap->areas) /* this is true, if we have a prolog only view */
 470		goto out;    /* or if 'pages_per_area' is 0 */
 471	act_entry = (debug_entry_t *) ((char*)id_snap->areas[p_info->act_area]
 472				[p_info->act_page] + p_info->act_entry);
 473                        
 474	if (act_entry->id.stck == 0LL)
 475			goto out;  /* empty entry */
 476	if (view->header_proc)
 477		len += view->header_proc(id_snap, view, p_info->act_area,
 478					act_entry, p_info->temp_buf + len);
 479	if (view->format_proc)
 480		len += view->format_proc(id_snap, view, p_info->temp_buf + len,
 481						DEBUG_DATA(act_entry));
 482out:
 483        return len;
 484}
 485
 486/*
 487 * debug_next_entry:
 488 * - goto next entry in p_info
 489 */
 490
 491static inline int
 492debug_next_entry(file_private_info_t *p_info)
 493{
 494	debug_info_t *id;
 495
 496	id = p_info->debug_info_snap;
 497	if(p_info->act_entry == DEBUG_PROLOG_ENTRY){
 498		p_info->act_entry = 0;
 499		p_info->act_page  = 0;
 500		goto out;
 501	}
 502	if(!id->areas)
 503		return 1;
 504	p_info->act_entry += id->entry_size;
 505	/* switch to next page, if we reached the end of the page  */
 506	if (p_info->act_entry > (PAGE_SIZE - id->entry_size)){
 507		/* next page */
 508		p_info->act_entry = 0;
 509		p_info->act_page += 1;
 510		if((p_info->act_page % id->pages_per_area) == 0) {
 511			/* next area */
 512        		p_info->act_area++;
 513			p_info->act_page=0;
 514		}
 515        	if(p_info->act_area >= id->nr_areas)
 516			return 1;
 517	}
 518out:
 519	return 0;	
 520}
 521
 522/*
 523 * debug_output:
 524 * - called for user read()
 525 * - copies formated debug entries to the user buffer
 526 */
 527
 528static ssize_t
 529debug_output(struct file *file,		/* file descriptor */
 530	    char __user *user_buf,	/* user buffer */
 531	    size_t  len,		/* length of buffer */
 532	    loff_t *offset)		/* offset in the file */
 533{
 534	size_t count = 0;
 535	size_t entry_offset;
 536	file_private_info_t *p_info;
 537
 538	p_info = ((file_private_info_t *) file->private_data);
 539	if (*offset != p_info->offset) 
 540		return -EPIPE;
 541	if(p_info->act_area >= p_info->debug_info_snap->nr_areas)
 542		return 0;
 543	entry_offset = p_info->act_entry_offset;
 544	while(count < len){
 545		int formatted_line_size;
 546		int formatted_line_residue;
 547		int user_buf_residue;
 548		size_t copy_size;
 549
 550		formatted_line_size = debug_format_entry(p_info);
 551		formatted_line_residue = formatted_line_size - entry_offset;
 552		user_buf_residue = len-count;
 553		copy_size = min(user_buf_residue, formatted_line_residue);
 554		if(copy_size){
 555			if (copy_to_user(user_buf + count, p_info->temp_buf
 556					+ entry_offset, copy_size))
 557				return -EFAULT;
 558			count += copy_size;
 559			entry_offset += copy_size;
 560		}
 561		if(copy_size == formatted_line_residue){
 562			entry_offset = 0;
 563			if(debug_next_entry(p_info))
 564				goto out;
 565		}
 566	}
 567out:
 568	p_info->offset           = *offset + count;
 569	p_info->act_entry_offset = entry_offset;
 570	*offset = p_info->offset;
 571	return count;
 572}
 573
 574/*
 575 * debug_input:
 576 * - called for user write()
 577 * - calls input function of view
 578 */
 579
 580static ssize_t
 581debug_input(struct file *file, const char __user *user_buf, size_t length,
 582		loff_t *offset)
 583{
 584	int rc = 0;
 585	file_private_info_t *p_info;
 586
 587	mutex_lock(&debug_mutex);
 588	p_info = ((file_private_info_t *) file->private_data);
 589	if (p_info->view->input_proc)
 590		rc = p_info->view->input_proc(p_info->debug_info_org,
 591					      p_info->view, file, user_buf,
 592					      length, offset);
 593	else
 594		rc = -EPERM;
 595	mutex_unlock(&debug_mutex);
 596	return rc;		/* number of input characters */
 597}
 598
 599/*
 600 * debug_open:
 601 * - called for user open()
 602 * - copies formated output to private_data area of the file
 603 *   handle
 604 */
 605
 606static int
 607debug_open(struct inode *inode, struct file *file)
 608{
 609	int i, rc = 0;
 610	file_private_info_t *p_info;
 611	debug_info_t *debug_info, *debug_info_snapshot;
 612
 613	mutex_lock(&debug_mutex);
 614	debug_info = file_inode(file)->i_private;
 615	/* find debug view */
 616	for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
 617		if (!debug_info->views[i])
 618			continue;
 619		else if (debug_info->debugfs_entries[i] ==
 620			 file->f_path.dentry) {
 621			goto found;	/* found view ! */
 622		}
 623	}
 624	/* no entry found */
 625	rc = -EINVAL;
 626	goto out;
 627
 628found:
 629
 630	/* Make snapshot of current debug areas to get it consistent.     */
 631	/* To copy all the areas is only needed, if we have a view which  */
 632	/* formats the debug areas. */
 633
 634	if(!debug_info->views[i]->format_proc &&
 635		!debug_info->views[i]->header_proc){
 636		debug_info_snapshot = debug_info_copy(debug_info, NO_AREAS);
 637	} else {
 638		debug_info_snapshot = debug_info_copy(debug_info, ALL_AREAS);
 639	}
 640
 641	if(!debug_info_snapshot){
 642		rc = -ENOMEM;
 643		goto out;
 644	}
 645	p_info = kmalloc(sizeof(file_private_info_t),
 646						GFP_KERNEL);
 647	if(!p_info){
 648		debug_info_free(debug_info_snapshot);
 649		rc = -ENOMEM;
 650		goto out;
 651	}
 652	p_info->offset = 0;
 653	p_info->debug_info_snap = debug_info_snapshot;
 654	p_info->debug_info_org  = debug_info;
 655	p_info->view = debug_info->views[i];
 656	p_info->act_area = 0;
 657	p_info->act_page = 0;
 658	p_info->act_entry = DEBUG_PROLOG_ENTRY;
 659	p_info->act_entry_offset = 0;
 660	file->private_data = p_info;
 661	debug_info_get(debug_info);
 662	nonseekable_open(inode, file);
 663out:
 664	mutex_unlock(&debug_mutex);
 665	return rc;
 666}
 667
 668/*
 669 * debug_close:
 670 * - called for user close()
 671 * - deletes  private_data area of the file handle
 672 */
 673
 674static int
 675debug_close(struct inode *inode, struct file *file)
 676{
 677	file_private_info_t *p_info;
 678	p_info = (file_private_info_t *) file->private_data;
 679	if(p_info->debug_info_snap)
 680		debug_info_free(p_info->debug_info_snap);
 681	debug_info_put(p_info->debug_info_org);
 682	kfree(file->private_data);
 683	return 0;		/* success */
 684}
 685
 686/*
 687 * debug_register_mode:
 688 * - Creates and initializes debug area for the caller
 689 *   The mode parameter allows to specify access rights for the s390dbf files
 690 * - Returns handle for debug area
 691 */
 692
 693debug_info_t *debug_register_mode(const char *name, int pages_per_area,
 694				  int nr_areas, int buf_size, umode_t mode,
 695				  uid_t uid, gid_t gid)
 696{
 697	debug_info_t *rc = NULL;
 698
 699	/* Since debugfs currently does not support uid/gid other than root, */
 700	/* we do not allow gid/uid != 0 until we get support for that. */
 701	if ((uid != 0) || (gid != 0))
 702		pr_warning("Root becomes the owner of all s390dbf files "
 703			   "in sysfs\n");
 704	BUG_ON(!initialized);
 705	mutex_lock(&debug_mutex);
 706
 707        /* create new debug_info */
 708
 709	rc = debug_info_create(name, pages_per_area, nr_areas, buf_size, mode);
 710	if(!rc) 
 711		goto out;
 712	debug_register_view(rc, &debug_level_view);
 713        debug_register_view(rc, &debug_flush_view);
 714	debug_register_view(rc, &debug_pages_view);
 715out:
 716        if (!rc){
 717		pr_err("Registering debug feature %s failed\n", name);
 718        }
 719	mutex_unlock(&debug_mutex);
 720	return rc;
 721}
 722EXPORT_SYMBOL(debug_register_mode);
 723
 724/*
 725 * debug_register:
 726 * - creates and initializes debug area for the caller
 727 * - returns handle for debug area
 728 */
 729
 730debug_info_t *debug_register(const char *name, int pages_per_area,
 731			     int nr_areas, int buf_size)
 732{
 733	return debug_register_mode(name, pages_per_area, nr_areas, buf_size,
 734				   S_IRUSR | S_IWUSR, 0, 0);
 735}
 736EXPORT_SYMBOL(debug_register);
 737
 738/*
 739 * debug_unregister:
 740 * - give back debug area
 741 */
 742
 743void
 744debug_unregister(debug_info_t * id)
 745{
 746	if (!id)
 747		goto out;
 748	mutex_lock(&debug_mutex);
 749	debug_info_put(id);
 750	mutex_unlock(&debug_mutex);
 751
 752out:
 753	return;
 754}
 755EXPORT_SYMBOL(debug_unregister);
 756
 757/*
 758 * debug_set_size:
 759 * - set area size (number of pages) and number of areas
 760 */
 761static int
 762debug_set_size(debug_info_t* id, int nr_areas, int pages_per_area)
 763{
 764	unsigned long flags;
 765	debug_entry_t *** new_areas;
 766	int rc=0;
 767
 768	if(!id || (nr_areas <= 0) || (pages_per_area < 0))
 769		return -EINVAL;
 770	if(pages_per_area > 0){
 771		new_areas = debug_areas_alloc(pages_per_area, nr_areas);
 772		if(!new_areas) {
 773			pr_info("Allocating memory for %i pages failed\n",
 774				pages_per_area);
 775			rc = -ENOMEM;
 776			goto out;
 777		}
 778	} else {
 779		new_areas = NULL;
 780	}
 781	spin_lock_irqsave(&id->lock,flags);
 782	debug_areas_free(id);
 783	id->areas = new_areas;
 784	id->nr_areas = nr_areas;
 785	id->pages_per_area = pages_per_area;
 786	id->active_area = 0;
 787	memset(id->active_entries,0,sizeof(int)*id->nr_areas);
 788	memset(id->active_pages, 0, sizeof(int)*id->nr_areas);
 789	spin_unlock_irqrestore(&id->lock,flags);
 790	pr_info("%s: set new size (%i pages)\n" ,id->name, pages_per_area);
 791out:
 792	return rc;
 793}
 794
 795/*
 796 * debug_set_level:
 797 * - set actual debug level
 798 */
 799
 800void
 801debug_set_level(debug_info_t* id, int new_level)
 802{
 803	unsigned long flags;
 804	if(!id)
 805		return;	
 806	spin_lock_irqsave(&id->lock,flags);
 807        if(new_level == DEBUG_OFF_LEVEL){
 808                id->level = DEBUG_OFF_LEVEL;
 809		pr_info("%s: switched off\n",id->name);
 810        } else if ((new_level > DEBUG_MAX_LEVEL) || (new_level < 0)) {
 811		pr_info("%s: level %i is out of range (%i - %i)\n",
 812                        id->name, new_level, 0, DEBUG_MAX_LEVEL);
 813        } else {
 814                id->level = new_level;
 815        }
 816	spin_unlock_irqrestore(&id->lock,flags);
 817}
 818EXPORT_SYMBOL(debug_set_level);
 819
 820/*
 821 * proceed_active_entry:
 822 * - set active entry to next in the ring buffer
 823 */
 824
 825static inline void
 826proceed_active_entry(debug_info_t * id)
 827{
 828	if ((id->active_entries[id->active_area] += id->entry_size)
 829	    > (PAGE_SIZE - id->entry_size)){
 830		id->active_entries[id->active_area] = 0;
 831		id->active_pages[id->active_area] =
 832			(id->active_pages[id->active_area] + 1) %
 833			id->pages_per_area;
 834	}
 835}
 836
 837/*
 838 * proceed_active_area:
 839 * - set active area to next in the ring buffer
 840 */
 841
 842static inline void
 843proceed_active_area(debug_info_t * id)
 844{
 845	id->active_area++;
 846	id->active_area = id->active_area % id->nr_areas;
 847}
 848
 849/*
 850 * get_active_entry:
 851 */
 852
 853static inline debug_entry_t*
 854get_active_entry(debug_info_t * id)
 855{
 856	return (debug_entry_t *) (((char *) id->areas[id->active_area]
 857					[id->active_pages[id->active_area]]) +
 858					id->active_entries[id->active_area]);
 859}
 860
 861/*
 862 * debug_finish_entry:
 863 * - set timestamp, caller address, cpu number etc.
 864 */
 865
 866static inline void
 867debug_finish_entry(debug_info_t * id, debug_entry_t* active, int level,
 868			int exception)
 869{
 870	active->id.stck = get_tod_clock_fast();
 871	active->id.fields.cpuid = smp_processor_id();
 872	active->caller = __builtin_return_address(0);
 873	active->id.fields.exception = exception;
 874	active->id.fields.level     = level;
 875	proceed_active_entry(id);
 876	if(exception)
 877		proceed_active_area(id);
 878}
 879
 880static int debug_stoppable=1;
 881static int debug_active=1;
 882
 883#define CTL_S390DBF_STOPPABLE 5678
 884#define CTL_S390DBF_ACTIVE 5679
 885
 886/*
 887 * proc handler for the running debug_active sysctl
 888 * always allow read, allow write only if debug_stoppable is set or
 889 * if debug_active is already off
 890 */
 891static int
 892s390dbf_procactive(struct ctl_table *table, int write,
 893                     void __user *buffer, size_t *lenp, loff_t *ppos)
 894{
 895	if (!write || debug_stoppable || !debug_active)
 896		return proc_dointvec(table, write, buffer, lenp, ppos);
 897	else
 898		return 0;
 899}
 900
 901
 902static struct ctl_table s390dbf_table[] = {
 903	{
 904		.procname       = "debug_stoppable",
 905		.data		= &debug_stoppable,
 906		.maxlen		= sizeof(int),
 907		.mode           = S_IRUGO | S_IWUSR,
 908		.proc_handler   = proc_dointvec,
 909	},
 910	 {
 911		.procname       = "debug_active",
 912		.data		= &debug_active,
 913		.maxlen		= sizeof(int),
 914		.mode           = S_IRUGO | S_IWUSR,
 915		.proc_handler   = s390dbf_procactive,
 916	},
 917	{ }
 918};
 919
 920static struct ctl_table s390dbf_dir_table[] = {
 921	{
 922		.procname       = "s390dbf",
 923		.maxlen         = 0,
 924		.mode           = S_IRUGO | S_IXUGO,
 925		.child          = s390dbf_table,
 926	},
 927	{ }
 928};
 929
 930static struct ctl_table_header *s390dbf_sysctl_header;
 931
 932void
 933debug_stop_all(void)
 934{
 935	if (debug_stoppable)
 936		debug_active = 0;
 937}
 938EXPORT_SYMBOL(debug_stop_all);
 939
 940void debug_set_critical(void)
 941{
 942	debug_critical = 1;
 943}
 944
 945/*
 946 * debug_event_common:
 947 * - write debug entry with given size
 948 */
 949
 950debug_entry_t*
 951debug_event_common(debug_info_t * id, int level, const void *buf, int len)
 952{
 953	unsigned long flags;
 954	debug_entry_t *active;
 955
 956	if (!debug_active || !id->areas)
 957		return NULL;
 958	if (debug_critical) {
 959		if (!spin_trylock_irqsave(&id->lock, flags))
 960			return NULL;
 961	} else
 962		spin_lock_irqsave(&id->lock, flags);
 963	active = get_active_entry(id);
 964	memset(DEBUG_DATA(active), 0, id->buf_size);
 965	memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
 966	debug_finish_entry(id, active, level, 0);
 967	spin_unlock_irqrestore(&id->lock, flags);
 968
 969	return active;
 970}
 971EXPORT_SYMBOL(debug_event_common);
 972
 973/*
 974 * debug_exception_common:
 975 * - write debug entry with given size and switch to next debug area
 976 */
 977
 978debug_entry_t
 979*debug_exception_common(debug_info_t * id, int level, const void *buf, int len)
 980{
 981	unsigned long flags;
 982	debug_entry_t *active;
 983
 984	if (!debug_active || !id->areas)
 985		return NULL;
 986	if (debug_critical) {
 987		if (!spin_trylock_irqsave(&id->lock, flags))
 988			return NULL;
 989	} else
 990		spin_lock_irqsave(&id->lock, flags);
 991	active = get_active_entry(id);
 992	memset(DEBUG_DATA(active), 0, id->buf_size);
 993	memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
 994	debug_finish_entry(id, active, level, 1);
 995	spin_unlock_irqrestore(&id->lock, flags);
 996
 997	return active;
 998}
 999EXPORT_SYMBOL(debug_exception_common);
1000
1001/*
1002 * counts arguments in format string for sprintf view
1003 */
1004
1005static inline int
1006debug_count_numargs(char *string)
1007{
1008	int numargs=0;
1009
1010	while(*string) {
1011		if(*string++=='%')
1012			numargs++;
1013	}
1014	return(numargs);
1015}
1016
1017/*
1018 * debug_sprintf_event:
1019 */
1020
1021debug_entry_t*
1022debug_sprintf_event(debug_info_t* id, int level,char *string,...)
1023{
1024	va_list   ap;
1025	int numargs,idx;
1026	unsigned long flags;
1027	debug_sprintf_entry_t *curr_event;
1028	debug_entry_t *active;
1029
1030	if((!id) || (level > id->level))
1031		return NULL;
1032	if (!debug_active || !id->areas)
1033		return NULL;
1034	numargs=debug_count_numargs(string);
1035
1036	if (debug_critical) {
1037		if (!spin_trylock_irqsave(&id->lock, flags))
1038			return NULL;
1039	} else
1040		spin_lock_irqsave(&id->lock, flags);
1041	active = get_active_entry(id);
1042	curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active);
1043	va_start(ap,string);
1044	curr_event->string=string;
1045	for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
1046		curr_event->args[idx]=va_arg(ap,long);
1047	va_end(ap);
1048	debug_finish_entry(id, active, level, 0);
1049	spin_unlock_irqrestore(&id->lock, flags);
1050
1051	return active;
1052}
1053EXPORT_SYMBOL(debug_sprintf_event);
1054
1055/*
1056 * debug_sprintf_exception:
1057 */
1058
1059debug_entry_t*
1060debug_sprintf_exception(debug_info_t* id, int level,char *string,...)
1061{
1062	va_list   ap;
1063	int numargs,idx;
1064	unsigned long flags;
1065	debug_sprintf_entry_t *curr_event;
1066	debug_entry_t *active;
1067
1068	if((!id) || (level > id->level))
1069		return NULL;
1070	if (!debug_active || !id->areas)
1071		return NULL;
1072
1073	numargs=debug_count_numargs(string);
1074
1075	if (debug_critical) {
1076		if (!spin_trylock_irqsave(&id->lock, flags))
1077			return NULL;
1078	} else
1079		spin_lock_irqsave(&id->lock, flags);
1080	active = get_active_entry(id);
1081	curr_event=(debug_sprintf_entry_t *)DEBUG_DATA(active);
1082	va_start(ap,string);
1083	curr_event->string=string;
1084	for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
1085		curr_event->args[idx]=va_arg(ap,long);
1086	va_end(ap);
1087	debug_finish_entry(id, active, level, 1);
1088	spin_unlock_irqrestore(&id->lock, flags);
1089
1090	return active;
1091}
1092EXPORT_SYMBOL(debug_sprintf_exception);
1093
1094/*
1095 * debug_register_view:
1096 */
1097
1098int
1099debug_register_view(debug_info_t * id, struct debug_view *view)
1100{
1101	int rc = 0;
1102	int i;
1103	unsigned long flags;
1104	umode_t mode;
1105	struct dentry *pde;
1106
1107	if (!id)
1108		goto out;
1109	mode = (id->mode | S_IFREG) & ~S_IXUGO;
1110	if (!(view->prolog_proc || view->format_proc || view->header_proc))
1111		mode &= ~(S_IRUSR | S_IRGRP | S_IROTH);
1112	if (!view->input_proc)
1113		mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);
1114	pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry,
1115				id , &debug_file_ops);
1116	if (!pde){
1117		pr_err("Registering view %s/%s failed due to out of "
1118		       "memory\n", id->name,view->name);
1119		rc = -1;
1120		goto out;
1121	}
1122	spin_lock_irqsave(&id->lock, flags);
1123	for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1124		if (!id->views[i])
1125			break;
1126	}
1127	if (i == DEBUG_MAX_VIEWS) {
1128		pr_err("Registering view %s/%s would exceed the maximum "
1129		       "number of views %i\n", id->name, view->name, i);
1130		rc = -1;
1131	} else {
1132		id->views[i] = view;
1133		id->debugfs_entries[i] = pde;
1134	}
1135	spin_unlock_irqrestore(&id->lock, flags);
1136	if (rc)
1137		debugfs_remove(pde);
1138out:
1139	return rc;
1140}
1141EXPORT_SYMBOL(debug_register_view);
1142
1143/*
1144 * debug_unregister_view:
1145 */
1146
1147int
1148debug_unregister_view(debug_info_t * id, struct debug_view *view)
1149{
1150	struct dentry *dentry = NULL;
1151	unsigned long flags;
1152	int i, rc = 0;
1153
1154	if (!id)
1155		goto out;
1156	spin_lock_irqsave(&id->lock, flags);
1157	for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1158		if (id->views[i] == view)
1159			break;
1160	}
1161	if (i == DEBUG_MAX_VIEWS)
1162		rc = -1;
1163	else {
1164		dentry = id->debugfs_entries[i];
1165		id->views[i] = NULL;
1166		id->debugfs_entries[i] = NULL;
1167	}
1168	spin_unlock_irqrestore(&id->lock, flags);
1169	debugfs_remove(dentry);
1170out:
1171	return rc;
1172}
1173EXPORT_SYMBOL(debug_unregister_view);
1174
1175static inline char *
1176debug_get_user_string(const char __user *user_buf, size_t user_len)
1177{
1178	char* buffer;
1179
1180	buffer = kmalloc(user_len + 1, GFP_KERNEL);
1181	if (!buffer)
1182		return ERR_PTR(-ENOMEM);
1183	if (copy_from_user(buffer, user_buf, user_len) != 0) {
1184		kfree(buffer);
1185		return ERR_PTR(-EFAULT);
1186	}
1187	/* got the string, now strip linefeed. */
1188	if (buffer[user_len - 1] == '\n')
1189		buffer[user_len - 1] = 0;
1190	else
1191		buffer[user_len] = 0;
1192        return buffer;
1193}
1194
1195static inline int
1196debug_get_uint(char *buf)
1197{
1198	int rc;
1199
1200	buf = skip_spaces(buf);
1201	rc = simple_strtoul(buf, &buf, 10);
1202	if(*buf){
1203		rc = -EINVAL;
1204	}
1205	return rc;
1206}
1207
1208/*
1209 * functions for debug-views
1210 ***********************************
1211*/
1212
1213/*
1214 * prints out actual debug level
1215 */
1216
1217static int
1218debug_prolog_pages_fn(debug_info_t * id,
1219				 struct debug_view *view, char *out_buf)
1220{
1221	return sprintf(out_buf, "%i\n", id->pages_per_area);
1222}
1223
1224/*
1225 * reads new size (number of pages per debug area)
1226 */
1227
1228static int
1229debug_input_pages_fn(debug_info_t * id, struct debug_view *view,
1230			struct file *file, const char __user *user_buf,
1231			size_t user_len, loff_t * offset)
1232{
1233	char *str;
1234	int rc,new_pages;
1235
1236	if (user_len > 0x10000)
1237                user_len = 0x10000;
1238	if (*offset != 0){
1239		rc = -EPIPE;
1240		goto out;
1241	}
1242	str = debug_get_user_string(user_buf,user_len);
1243	if(IS_ERR(str)){
1244		rc = PTR_ERR(str);
1245		goto out;
1246	}
1247	new_pages = debug_get_uint(str);
1248	if(new_pages < 0){
1249		rc = -EINVAL;
1250		goto free_str;
1251	}
1252	rc = debug_set_size(id,id->nr_areas, new_pages);
1253	if(rc != 0){
1254		rc = -EINVAL;
1255		goto free_str;
1256	}
1257	rc = user_len;
1258free_str:
1259	kfree(str);
1260out:
1261	*offset += user_len;
1262	return rc;		/* number of input characters */
1263}
1264
1265/*
1266 * prints out actual debug level
1267 */
1268
1269static int
1270debug_prolog_level_fn(debug_info_t * id, struct debug_view *view, char *out_buf)
1271{
1272	int rc = 0;
1273
1274	if(id->level == DEBUG_OFF_LEVEL) {
1275		rc = sprintf(out_buf,"-\n");
1276	}
1277	else {
1278		rc = sprintf(out_buf, "%i\n", id->level);
1279	}
1280	return rc;
1281}
1282
1283/*
1284 * reads new debug level
1285 */
1286
1287static int
1288debug_input_level_fn(debug_info_t * id, struct debug_view *view,
1289			struct file *file, const char __user *user_buf,
1290			size_t user_len, loff_t * offset)
1291{
1292	char *str;
1293	int rc,new_level;
1294
1295	if (user_len > 0x10000)
1296                user_len = 0x10000;
1297	if (*offset != 0){
1298		rc = -EPIPE;
1299		goto out;
1300	}
1301	str = debug_get_user_string(user_buf,user_len);
1302	if(IS_ERR(str)){
1303		rc = PTR_ERR(str);
1304		goto out;
1305	}
1306	if(str[0] == '-'){
1307		debug_set_level(id, DEBUG_OFF_LEVEL);
1308		rc = user_len;
1309		goto free_str;
1310	} else {
1311		new_level = debug_get_uint(str);
1312	}
1313	if(new_level < 0) {
1314		pr_warning("%s is not a valid level for a debug "
1315			   "feature\n", str);
1316		rc = -EINVAL;
1317	} else {
1318		debug_set_level(id, new_level);
1319		rc = user_len;
1320	}
1321free_str:
1322	kfree(str);
1323out:
1324	*offset += user_len;
1325	return rc;		/* number of input characters */
1326}
1327
1328
1329/*
1330 * flushes debug areas
1331 */
1332 
1333static void debug_flush(debug_info_t* id, int area)
1334{
1335        unsigned long flags;
1336        int i,j;
1337
1338        if(!id || !id->areas)
1339                return;
1340        spin_lock_irqsave(&id->lock,flags);
1341        if(area == DEBUG_FLUSH_ALL){
1342                id->active_area = 0;
1343                memset(id->active_entries, 0, id->nr_areas * sizeof(int));
1344                for (i = 0; i < id->nr_areas; i++) {
1345			id->active_pages[i] = 0;
1346			for(j = 0; j < id->pages_per_area; j++) {
1347                        	memset(id->areas[i][j], 0, PAGE_SIZE);
1348			}
1349		}
1350        } else if(area >= 0 && area < id->nr_areas) {
1351                id->active_entries[area] = 0;
1352		id->active_pages[area] = 0;
1353		for(i = 0; i < id->pages_per_area; i++) {
1354                	memset(id->areas[area][i],0,PAGE_SIZE);
1355		}
1356        }
1357        spin_unlock_irqrestore(&id->lock,flags);
1358}
1359
1360/*
1361 * view function: flushes debug areas 
1362 */
1363
1364static int
1365debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
1366			struct file *file, const char __user *user_buf,
1367			size_t user_len, loff_t * offset)
1368{
1369        char input_buf[1];
1370        int rc = user_len;
1371
1372	if (user_len > 0x10000)
1373                user_len = 0x10000;
1374        if (*offset != 0){
1375		rc = -EPIPE;
1376                goto out;
1377	}
1378        if (copy_from_user(input_buf, user_buf, 1)){
1379                rc = -EFAULT;
1380                goto out;
1381        }
1382        if(input_buf[0] == '-') { 
1383                debug_flush(id, DEBUG_FLUSH_ALL);
1384                goto out;
1385        }
1386        if (isdigit(input_buf[0])) {
1387                int area = ((int) input_buf[0] - (int) '0');
1388                debug_flush(id, area);
1389                goto out;
1390        }
1391
1392	pr_info("Flushing debug data failed because %c is not a valid "
1393		 "area\n", input_buf[0]);
1394
1395out:
1396        *offset += user_len;
1397        return rc;              /* number of input characters */
1398}
1399
1400/*
1401 * prints debug header in raw format
1402 */
1403
1404static int
1405debug_raw_header_fn(debug_info_t * id, struct debug_view *view,
1406			int area, debug_entry_t * entry, char *out_buf)
1407{
1408        int rc;
1409
1410	rc = sizeof(debug_entry_t);
1411	memcpy(out_buf,entry,sizeof(debug_entry_t));
1412        return rc;
1413}
1414
1415/*
1416 * prints debug data in raw format
1417 */
1418
1419static int
1420debug_raw_format_fn(debug_info_t * id, struct debug_view *view,
1421			       char *out_buf, const char *in_buf)
1422{
1423	int rc;
1424
1425	rc = id->buf_size;
1426	memcpy(out_buf, in_buf, id->buf_size);
1427	return rc;
1428}
1429
1430/*
1431 * prints debug data in hex/ascii format
1432 */
1433
1434static int
1435debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
1436	    		  char *out_buf, const char *in_buf)
1437{
1438	int i, rc = 0;
1439
1440	for (i = 0; i < id->buf_size; i++) {
1441                rc += sprintf(out_buf + rc, "%02x ",
1442                              ((unsigned char *) in_buf)[i]);
1443        }
1444	rc += sprintf(out_buf + rc, "| ");
1445	for (i = 0; i < id->buf_size; i++) {
1446		unsigned char c = in_buf[i];
1447		if (isascii(c) && isprint(c))
1448			rc += sprintf(out_buf + rc, "%c", c);
1449		else
1450			rc += sprintf(out_buf + rc, ".");
1451	}
1452	rc += sprintf(out_buf + rc, "\n");
1453	return rc;
1454}
1455
1456/*
1457 * prints header for debug entry
1458 */
1459
1460int
1461debug_dflt_header_fn(debug_info_t * id, struct debug_view *view,
1462			 int area, debug_entry_t * entry, char *out_buf)
1463{
1464	struct timespec time_spec;
1465	char *except_str;
1466	unsigned long caller;
1467	int rc = 0;
1468	unsigned int level;
1469
1470	level = entry->id.fields.level;
1471	stck_to_timespec(entry->id.stck, &time_spec);
1472
1473	if (entry->id.fields.exception)
1474		except_str = "*";
1475	else
1476		except_str = "-";
1477	caller = ((unsigned long) entry->caller) & PSW_ADDR_INSN;
1478	rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %p  ",
1479		      area, time_spec.tv_sec, time_spec.tv_nsec / 1000, level,
1480		      except_str, entry->id.fields.cpuid, (void *) caller);
 
1481	return rc;
1482}
1483EXPORT_SYMBOL(debug_dflt_header_fn);
1484
1485/*
1486 * prints debug data sprintf-formated:
1487 * debug_sprinf_event/exception calls must be used together with this view
1488 */
1489
1490#define DEBUG_SPRINTF_MAX_ARGS 10
1491
1492static int
1493debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view,
1494                        char *out_buf, debug_sprintf_entry_t *curr_event)
1495{
1496	int num_longs, num_used_args = 0,i, rc = 0;
1497	int index[DEBUG_SPRINTF_MAX_ARGS];
1498
1499	/* count of longs fit into one entry */
1500	num_longs = id->buf_size /  sizeof(long); 
1501
1502	if(num_longs < 1)
1503		goto out; /* bufsize of entry too small */
1504	if(num_longs == 1) {
1505		/* no args, we use only the string */
1506		strcpy(out_buf, curr_event->string);
1507		rc = strlen(curr_event->string);
1508		goto out;
1509	}
1510
1511	/* number of arguments used for sprintf (without the format string) */
1512	num_used_args   = min(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1));
1513
1514	memset(index,0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int));
1515
1516	for(i = 0; i < num_used_args; i++)
1517		index[i] = i;
1518
1519	rc =  sprintf(out_buf, curr_event->string, curr_event->args[index[0]],
1520		curr_event->args[index[1]], curr_event->args[index[2]],
1521		curr_event->args[index[3]], curr_event->args[index[4]],
1522		curr_event->args[index[5]], curr_event->args[index[6]],
1523		curr_event->args[index[7]], curr_event->args[index[8]],
1524		curr_event->args[index[9]]);
1525
1526out:
1527
1528	return rc;
1529}
1530
1531/*
1532 * debug_init:
1533 * - is called exactly once to initialize the debug feature
1534 */
1535static int __init debug_init(void)
1536{
1537	s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table);
1538	mutex_lock(&debug_mutex);
1539	debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT, NULL);
1540	initialized = 1;
1541	mutex_unlock(&debug_mutex);
1542	return 0;
1543}
1544postcore_initcall(debug_init);