debug.c 35.2 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6 7 8 9 10 11 12
/*
 *  arch/s390/kernel/debug.c
 *   S/390 debug facility
 *
 *    Copyright (C) 1999, 2000 IBM Deutschland Entwicklung GmbH,
 *                             IBM Corporation
 *    Author(s): Michael Holzheu (holzheu@de.ibm.com),
 *               Holger Smolinski (Holger.Smolinski@de.ibm.com)
 *
 *    Bugreports to: <Linux390@de.ibm.com>
 */

13 14 15
#define KMSG_COMPONENT "s390dbf"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

L
Linus Torvalds 已提交
16 17 18 19 20
#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/ctype.h>
21
#include <linux/string.h>
L
Linus Torvalds 已提交
22 23 24 25
#include <linux/sysctl.h>
#include <asm/uaccess.h>
#include <linux/module.h>
#include <linux/init.h>
26 27
#include <linux/fs.h>
#include <linux/debugfs.h>
L
Linus Torvalds 已提交
28 29 30 31 32

#include <asm/debug.h>

#define DEBUG_PROLOG_ENTRY -1

33 34 35
#define ALL_AREAS 0 /* copy all debug areas */
#define NO_AREAS  1 /* copy no debug areas */

L
Linus Torvalds 已提交
36 37 38 39 40
/* typedefs */

typedef struct file_private_info {
	loff_t offset;			/* offset of last read in file */
	int    act_area;                /* number of last formated area */
41
	int    act_page;                /* act page in given area */
L
Linus Torvalds 已提交
42 43
	int    act_entry;               /* last formated entry (offset */
                                        /* relative to beginning of last */
44
                                        /* formated page) */
L
Linus Torvalds 已提交
45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
	size_t act_entry_offset;        /* up to this offset we copied */
					/* in last read the last formated */
					/* entry to userland */
	char   temp_buf[2048];		/* buffer for output */
	debug_info_t *debug_info_org;   /* original debug information */
	debug_info_t *debug_info_snap;	/* snapshot of debug information */
	struct debug_view *view;	/* used view of debug info */
} file_private_info_t;

typedef struct
{
	char *string;
	/* 
	 * This assumes that all args are converted into longs 
	 * on L/390 this is the case for all types of parameter 
	 * except of floats, and long long (32 bit) 
61 62
	 *
	 */
L
Linus Torvalds 已提交
63 64 65 66 67 68 69 70
	long args[0];
} debug_sprintf_entry_t;


/* internal function prototyes */

static int debug_init(void);
static ssize_t debug_output(struct file *file, char __user *user_buf,
71
			size_t user_len, loff_t * offset);
L
Linus Torvalds 已提交
72
static ssize_t debug_input(struct file *file, const char __user *user_buf,
73
			size_t user_len, loff_t * offset);
L
Linus Torvalds 已提交
74 75
static int debug_open(struct inode *inode, struct file *file);
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, mode_t mode);
L
Linus Torvalds 已提交
78 79 80
static void debug_info_get(debug_info_t *);
static void debug_info_put(debug_info_t *);
static int debug_prolog_level_fn(debug_info_t * id,
81
			struct debug_view *view, char *out_buf);
L
Linus Torvalds 已提交
82
static int debug_input_level_fn(debug_info_t * id, struct debug_view *view,
83 84 85 86 87 88 89
			struct file *file, const char __user *user_buf,
			size_t user_buf_size, loff_t * offset);
static int debug_prolog_pages_fn(debug_info_t * id,
			struct debug_view *view, char *out_buf);
static int debug_input_pages_fn(debug_info_t * id, struct debug_view *view,
			struct file *file, const char __user *user_buf,
			size_t user_buf_size, loff_t * offset);
L
Linus Torvalds 已提交
90
static int debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
91 92
			struct file *file, const char __user *user_buf,
			size_t user_buf_size, loff_t * offset);
L
Linus Torvalds 已提交
93
static int debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
94
			char *out_buf, const char *in_buf);
L
Linus Torvalds 已提交
95
static int debug_raw_format_fn(debug_info_t * id,
96 97
			struct debug_view *view, char *out_buf,
			const char *in_buf);
L
Linus Torvalds 已提交
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);
L
Linus Torvalds 已提交
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);
L
Linus Torvalds 已提交
103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123

/* globals */

struct debug_view debug_raw_view = {
	"raw",
	NULL,
	&debug_raw_header_fn,
	&debug_raw_format_fn,
	NULL,
	NULL
};

struct debug_view debug_hex_ascii_view = {
	"hex_ascii",
	NULL,
	&debug_dflt_header_fn,
	&debug_hex_ascii_format_fn,
	NULL,
	NULL
};

124
static struct debug_view debug_level_view = {
L
Linus Torvalds 已提交
125 126 127 128 129 130 131 132
	"level",
	&debug_prolog_level_fn,
	NULL,
	NULL,
	&debug_input_level_fn,
	NULL
};

133
static struct debug_view debug_pages_view = {
134 135 136 137 138 139 140 141
	"pages",
	&debug_prolog_pages_fn,
	NULL,
	NULL,
	&debug_input_pages_fn,
	NULL
};

142
static struct debug_view debug_flush_view = {
L
Linus Torvalds 已提交
143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159
        "flush",
        NULL,
        NULL,
        NULL,
        &debug_input_flush_fn,
        NULL
};

struct debug_view debug_sprintf_view = {
	"sprintf",
	NULL,
	&debug_dflt_header_fn,
	(debug_format_proc_t*)&debug_sprintf_format_fn,
	NULL,
	NULL
};

160
/* used by dump analysis tools to determine version of debug feature */
161
static unsigned int __used debug_feature_version = __DEBUG_FEATURE_VERSION;
L
Linus Torvalds 已提交
162 163 164 165 166

/* static globals */

static debug_info_t *debug_area_first = NULL;
static debug_info_t *debug_area_last = NULL;
167
static DEFINE_MUTEX(debug_mutex);
L
Linus Torvalds 已提交
168 169 170

static int initialized;

171
static const struct file_operations debug_file_ops = {
172
	.owner   = THIS_MODULE,
L
Linus Torvalds 已提交
173
	.read    = debug_output,
174
	.write   = debug_input,
L
Linus Torvalds 已提交
175 176 177 178
	.open    = debug_open,
	.release = debug_close,
};

179
static struct dentry *debug_debugfs_root_entry;
L
Linus Torvalds 已提交
180 181 182

/* functions */

183 184 185 186 187 188 189 190 191 192 193 194
/*
 * debug_areas_alloc
 * - Debug areas are implemented as a threedimensonal array:
 *   areas[areanumber][pagenumber][pageoffset]
 */

static debug_entry_t***
debug_areas_alloc(int pages_per_area, int nr_areas)
{
	debug_entry_t*** areas;
	int i,j;

195
	areas = kmalloc(nr_areas *
196 197 198 199 200
					sizeof(debug_entry_t**),
					GFP_KERNEL);
	if (!areas)
		goto fail_malloc_areas;
	for (i = 0; i < nr_areas; i++) {
201
		areas[i] = kmalloc(pages_per_area *
202 203 204 205 206
				sizeof(debug_entry_t*),GFP_KERNEL);
		if (!areas[i]) {
			goto fail_malloc_areas2;
		}
		for(j = 0; j < pages_per_area; j++) {
207
			areas[i][j] = kzalloc(PAGE_SIZE, GFP_KERNEL);
208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232
			if(!areas[i][j]) {
				for(j--; j >=0 ; j--) {
					kfree(areas[i][j]);
				}
				kfree(areas[i]);
				goto fail_malloc_areas2;
			}
		}
	}
	return areas;

fail_malloc_areas2:
	for(i--; i >= 0; i--){
		for(j=0; j < pages_per_area;j++){
			kfree(areas[i][j]);
		}
		kfree(areas[i]);
	}
	kfree(areas);
fail_malloc_areas:
	return NULL;

}


L
Linus Torvalds 已提交
233 234 235 236 237
/*
 * debug_info_alloc
 * - alloc new debug-info
 */

238
static debug_info_t*
239 240
debug_info_alloc(const char *name, int pages_per_area, int nr_areas,
		 int buf_size, int level, int mode)
L
Linus Torvalds 已提交
241 242 243 244 245
{
	debug_info_t* rc;

	/* alloc everything */

246
	rc = kmalloc(sizeof(debug_info_t), GFP_KERNEL);
L
Linus Torvalds 已提交
247 248
	if(!rc)
		goto fail_malloc_rc;
249
	rc->active_entries = kcalloc(nr_areas, sizeof(int), GFP_KERNEL);
250 251
	if(!rc->active_entries)
		goto fail_malloc_active_entries;
252
	rc->active_pages = kcalloc(nr_areas, sizeof(int), GFP_KERNEL);
253 254 255 256 257 258 259 260
	if(!rc->active_pages)
		goto fail_malloc_active_pages;
	if((mode == ALL_AREAS) && (pages_per_area != 0)){
		rc->areas = debug_areas_alloc(pages_per_area, nr_areas);
		if(!rc->areas)
			goto fail_malloc_areas;
	} else {
		rc->areas = NULL;
L
Linus Torvalds 已提交
261 262 263 264 265
	}

	/* initialize members */

	spin_lock_init(&rc->lock);
266 267 268 269 270 271
	rc->pages_per_area = pages_per_area;
	rc->nr_areas       = nr_areas;
	rc->active_area    = 0;
	rc->level          = level;
	rc->buf_size       = buf_size;
	rc->entry_size     = sizeof(debug_entry_t) + buf_size;
J
Jean Delvare 已提交
272
	strlcpy(rc->name, name, sizeof(rc->name));
L
Linus Torvalds 已提交
273
	memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *));
274 275
	memset(rc->debugfs_entries, 0 ,DEBUG_MAX_VIEWS *
		sizeof(struct dentry*));
L
Linus Torvalds 已提交
276 277 278 279 280
	atomic_set(&(rc->ref_count), 0);

	return rc;

fail_malloc_areas:
281 282 283 284
	kfree(rc->active_pages);
fail_malloc_active_pages:
	kfree(rc->active_entries);
fail_malloc_active_entries:
L
Linus Torvalds 已提交
285 286 287 288 289 290
	kfree(rc);
fail_malloc_rc:
	return NULL;
}

/*
291 292
 * debug_areas_free
 * - free all debug areas
L
Linus Torvalds 已提交
293 294
 */

295 296 297 298 299 300 301
static void
debug_areas_free(debug_info_t* db_info)
{
	int i,j;

	if(!db_info->areas)
		return;
L
Linus Torvalds 已提交
302
	for (i = 0; i < db_info->nr_areas; i++) {
303 304 305 306
		for(j = 0; j < db_info->pages_per_area; j++) {
			kfree(db_info->areas[i][j]);
		}
		kfree(db_info->areas[i]);
L
Linus Torvalds 已提交
307 308
	}
	kfree(db_info->areas);
309 310 311 312 313 314 315 316 317 318 319 320 321
	db_info->areas = NULL;
}

/*
 * debug_info_free
 * - free memory debug-info
 */

static void
debug_info_free(debug_info_t* db_info){
	debug_areas_free(db_info);
	kfree(db_info->active_entries);
	kfree(db_info->active_pages);
L
Linus Torvalds 已提交
322 323 324 325 326 327 328 329
	kfree(db_info);
}

/*
 * debug_info_create
 * - create new debug-info
 */

330
static debug_info_t*
331 332
debug_info_create(const char *name, int pages_per_area, int nr_areas,
		  int buf_size, mode_t mode)
L
Linus Torvalds 已提交
333 334 335
{
	debug_info_t* rc;

336 337
        rc = debug_info_alloc(name, pages_per_area, nr_areas, buf_size,
				DEBUG_DEFAULT_LEVEL, ALL_AREAS);
L
Linus Torvalds 已提交
338 339 340
        if(!rc) 
		goto out;

341 342
	rc->mode = mode & ~S_IFMT;

343 344 345
	/* create root directory */
        rc->debugfs_root_entry = debugfs_create_dir(rc->name,
					debug_debugfs_root_entry);
L
Linus Torvalds 已提交
346 347

	/* append new element to linked list */
348
        if (!debug_area_first) {
L
Linus Torvalds 已提交
349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369
                /* first element in list */
                debug_area_first = rc;
                rc->prev = NULL;
        } else {
                /* append element to end of list */
                debug_area_last->next = rc;
                rc->prev = debug_area_last;
        }
        debug_area_last = rc;
        rc->next = NULL;

	debug_info_get(rc);
out:
	return rc;
}

/*
 * debug_info_copy
 * - copy debug-info
 */

370 371
static debug_info_t*
debug_info_copy(debug_info_t* in, int mode)
L
Linus Torvalds 已提交
372
{
373
        int i,j;
L
Linus Torvalds 已提交
374
        debug_info_t* rc;
375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391
        unsigned long flags;

	/* get a consistent copy of the debug areas */
	do {
		rc = debug_info_alloc(in->name, in->pages_per_area,
			in->nr_areas, in->buf_size, in->level, mode);
		spin_lock_irqsave(&in->lock, flags);
		if(!rc)
			goto out;
		/* has something changed in the meantime ? */
		if((rc->pages_per_area == in->pages_per_area) &&
		   (rc->nr_areas == in->nr_areas)) {
			break;
		}
		spin_unlock_irqrestore(&in->lock, flags);
		debug_info_free(rc);
	} while (1);
392

J
Julia Lawall 已提交
393
	if (mode == NO_AREAS)
L
Linus Torvalds 已提交
394 395 396
                goto out;

        for(i = 0; i < in->nr_areas; i++){
397 398 399
		for(j = 0; j < in->pages_per_area; j++) {
			memcpy(rc->areas[i][j], in->areas[i][j],PAGE_SIZE);
		}
L
Linus Torvalds 已提交
400 401
        }
out:
402
        spin_unlock_irqrestore(&in->lock, flags);
L
Linus Torvalds 已提交
403 404 405 406 407 408 409 410
        return rc;
}

/*
 * debug_info_get
 * - increments reference count for debug-info
 */

411 412
static void
debug_info_get(debug_info_t * db_info)
L
Linus Torvalds 已提交
413 414 415 416 417 418 419 420 421 422
{
	if (db_info)
		atomic_inc(&db_info->ref_count);
}

/*
 * debug_info_put:
 * - decreases reference count for debug-info and frees it if necessary
 */

423 424
static void
debug_info_put(debug_info_t *db_info)
L
Linus Torvalds 已提交
425 426 427 428 429 430 431
{
	int i;

	if (!db_info)
		return;
	if (atomic_dec_and_test(&db_info->ref_count)) {
		for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
432
			if (!db_info->views[i])
L
Linus Torvalds 已提交
433
				continue;
434
			debugfs_remove(db_info->debugfs_entries[i]);
L
Linus Torvalds 已提交
435
		}
436
		debugfs_remove(db_info->debugfs_root_entry);
L
Linus Torvalds 已提交
437 438 439 440 441 442 443 444 445 446 447 448 449 450 451
		if(db_info == debug_area_first)
			debug_area_first = db_info->next;
		if(db_info == debug_area_last)
			debug_area_last = db_info->prev;
		if(db_info->prev) db_info->prev->next = db_info->next;
		if(db_info->next) db_info->next->prev = db_info->prev;
		debug_info_free(db_info);
	}
}

/*
 * debug_format_entry:
 * - format one debug entry and return size of formated data
 */

452 453
static int
debug_format_entry(file_private_info_t *p_info)
L
Linus Torvalds 已提交
454 455 456 457 458 459 460 461
{
	debug_info_t *id_snap   = p_info->debug_info_snap;
	struct debug_view *view = p_info->view;
	debug_entry_t *act_entry;
	size_t len = 0;
	if(p_info->act_entry == DEBUG_PROLOG_ENTRY){
		/* print prolog */
        	if (view->prolog_proc)
462
                	len += view->prolog_proc(id_snap,view,p_info->temp_buf);
L
Linus Torvalds 已提交
463 464
		goto out;
	}
465 466 467 468
	if (!id_snap->areas) /* this is true, if we have a prolog only view */
		goto out;    /* or if 'pages_per_area' is 0 */
	act_entry = (debug_entry_t *) ((char*)id_snap->areas[p_info->act_area]
				[p_info->act_page] + p_info->act_entry);
L
Linus Torvalds 已提交
469 470 471 472
                        
	if (act_entry->id.stck == 0LL)
			goto out;  /* empty entry */
	if (view->header_proc)
473
		len += view->header_proc(id_snap, view, p_info->act_area,
L
Linus Torvalds 已提交
474 475
					act_entry, p_info->temp_buf + len);
	if (view->format_proc)
476
		len += view->format_proc(id_snap, view, p_info->temp_buf + len,
L
Linus Torvalds 已提交
477
						DEBUG_DATA(act_entry));
478
out:
L
Linus Torvalds 已提交
479 480 481 482 483 484 485 486
        return len;
}

/*
 * debug_next_entry:
 * - goto next entry in p_info
 */

487
static inline int
488
debug_next_entry(file_private_info_t *p_info)
L
Linus Torvalds 已提交
489
{
490 491 492
	debug_info_t *id;

	id = p_info->debug_info_snap;
L
Linus Torvalds 已提交
493 494
	if(p_info->act_entry == DEBUG_PROLOG_ENTRY){
		p_info->act_entry = 0;
495
		p_info->act_page  = 0;
L
Linus Torvalds 已提交
496 497
		goto out;
	}
498 499 500 501 502 503
	if(!id->areas)
		return 1;
	p_info->act_entry += id->entry_size;
	/* switch to next page, if we reached the end of the page  */
	if (p_info->act_entry > (PAGE_SIZE - id->entry_size)){
		/* next page */
L
Linus Torvalds 已提交
504
		p_info->act_entry = 0;
505 506 507 508 509 510
		p_info->act_page += 1;
		if((p_info->act_page % id->pages_per_area) == 0) {
			/* next area */
        		p_info->act_area++;
			p_info->act_page=0;
		}
L
Linus Torvalds 已提交
511 512 513 514 515 516 517 518 519 520 521 522 523
        	if(p_info->act_area >= id->nr_areas)
			return 1;
	}
out:
	return 0;	
}

/*
 * debug_output:
 * - called for user read()
 * - copies formated debug entries to the user buffer
 */

524 525 526 527 528
static ssize_t
debug_output(struct file *file,		/* file descriptor */
	    char __user *user_buf,	/* user buffer */
	    size_t  len,		/* length of buffer */
	    loff_t *offset)		/* offset in the file */
L
Linus Torvalds 已提交
529 530
{
	size_t count = 0;
531
	size_t entry_offset;
L
Linus Torvalds 已提交
532 533 534 535 536 537 538 539 540
	file_private_info_t *p_info;

	p_info = ((file_private_info_t *) file->private_data);
	if (*offset != p_info->offset) 
		return -EPIPE;
	if(p_info->act_area >= p_info->debug_info_snap->nr_areas)
		return 0;
	entry_offset = p_info->act_entry_offset;
	while(count < len){
541 542 543 544 545 546 547 548 549 550 551 552 553 554 555
		int formatted_line_size;
		int formatted_line_residue;
		int user_buf_residue;
		size_t copy_size;

		formatted_line_size = debug_format_entry(p_info);
		formatted_line_residue = formatted_line_size - entry_offset;
		user_buf_residue = len-count;
		copy_size = min(user_buf_residue, formatted_line_residue);
		if(copy_size){
			if (copy_to_user(user_buf + count, p_info->temp_buf
					+ entry_offset, copy_size))
				return -EFAULT;
			count += copy_size;
			entry_offset += copy_size;
L
Linus Torvalds 已提交
556
		}
557 558 559
		if(copy_size == formatted_line_residue){
			entry_offset = 0;
			if(debug_next_entry(p_info))
L
Linus Torvalds 已提交
560
				goto out;
561
		}
L
Linus Torvalds 已提交
562 563 564
	}
out:
	p_info->offset           = *offset + count;
565
	p_info->act_entry_offset = entry_offset;
L
Linus Torvalds 已提交
566 567 568 569 570 571 572 573 574 575
	*offset = p_info->offset;
	return count;
}

/*
 * debug_input:
 * - called for user write()
 * - calls input function of view
 */

576 577 578
static ssize_t
debug_input(struct file *file, const char __user *user_buf, size_t length,
		loff_t *offset)
L
Linus Torvalds 已提交
579 580 581 582
{
	int rc = 0;
	file_private_info_t *p_info;

583
	mutex_lock(&debug_mutex);
L
Linus Torvalds 已提交
584 585 586 587 588 589 590
	p_info = ((file_private_info_t *) file->private_data);
	if (p_info->view->input_proc)
		rc = p_info->view->input_proc(p_info->debug_info_org,
					      p_info->view, file, user_buf,
					      length, offset);
	else
		rc = -EPERM;
591
	mutex_unlock(&debug_mutex);
L
Linus Torvalds 已提交
592 593 594 595 596 597 598 599 600 601
	return rc;		/* number of input characters */
}

/*
 * debug_open:
 * - called for user open()
 * - copies formated output to private_data area of the file
 *   handle
 */

602 603
static int
debug_open(struct inode *inode, struct file *file)
L
Linus Torvalds 已提交
604
{
605
	int i, rc = 0;
L
Linus Torvalds 已提交
606 607 608
	file_private_info_t *p_info;
	debug_info_t *debug_info, *debug_info_snapshot;

609
	mutex_lock(&debug_mutex);
J
Josef Sipek 已提交
610
	debug_info = file->f_path.dentry->d_inode->i_private;
611 612 613 614 615
	/* find debug view */
	for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
		if (!debug_info->views[i])
			continue;
		else if (debug_info->debugfs_entries[i] ==
J
Josef Sipek 已提交
616
			 file->f_path.dentry) {
617
			goto found;	/* found view ! */
L
Linus Torvalds 已提交
618 619 620 621 622 623
		}
	}
	/* no entry found */
	rc = -EINVAL;
	goto out;

624
found:
L
Linus Torvalds 已提交
625

626 627 628
	/* Make snapshot of current debug areas to get it consistent.     */
	/* To copy all the areas is only needed, if we have a view which  */
	/* formats the debug areas. */
L
Linus Torvalds 已提交
629

630 631 632 633 634 635
	if(!debug_info->views[i]->format_proc &&
		!debug_info->views[i]->header_proc){
		debug_info_snapshot = debug_info_copy(debug_info, NO_AREAS);
	} else {
		debug_info_snapshot = debug_info_copy(debug_info, ALL_AREAS);
	}
L
Linus Torvalds 已提交
636 637 638 639 640

	if(!debug_info_snapshot){
		rc = -ENOMEM;
		goto out;
	}
641
	p_info = kmalloc(sizeof(file_private_info_t),
642 643
						GFP_KERNEL);
	if(!p_info){
644
		debug_info_free(debug_info_snapshot);
L
Linus Torvalds 已提交
645 646 647 648 649 650 651 652
		rc = -ENOMEM;
		goto out;
	}
	p_info->offset = 0;
	p_info->debug_info_snap = debug_info_snapshot;
	p_info->debug_info_org  = debug_info;
	p_info->view = debug_info->views[i];
	p_info->act_area = 0;
653
	p_info->act_page = 0;
L
Linus Torvalds 已提交
654 655
	p_info->act_entry = DEBUG_PROLOG_ENTRY;
	p_info->act_entry_offset = 0;
656
	file->private_data = p_info;
L
Linus Torvalds 已提交
657
	debug_info_get(debug_info);
658
	nonseekable_open(inode, file);
659
out:
660
	mutex_unlock(&debug_mutex);
L
Linus Torvalds 已提交
661 662 663 664 665 666 667 668 669
	return rc;
}

/*
 * debug_close:
 * - called for user close()
 * - deletes  private_data area of the file handle
 */

670 671
static int
debug_close(struct inode *inode, struct file *file)
L
Linus Torvalds 已提交
672 673 674
{
	file_private_info_t *p_info;
	p_info = (file_private_info_t *) file->private_data;
675 676
	if(p_info->debug_info_snap)
		debug_info_free(p_info->debug_info_snap);
L
Linus Torvalds 已提交
677 678 679 680 681 682
	debug_info_put(p_info->debug_info_org);
	kfree(file->private_data);
	return 0;		/* success */
}

/*
683 684 685 686
 * debug_register_mode:
 * - Creates and initializes debug area for the caller
 *   The mode parameter allows to specify access rights for the s390dbf files
 * - Returns handle for debug area
L
Linus Torvalds 已提交
687 688
 */

689 690 691
debug_info_t *debug_register_mode(const char *name, int pages_per_area,
				  int nr_areas, int buf_size, mode_t mode,
				  uid_t uid, gid_t gid)
L
Linus Torvalds 已提交
692 693 694
{
	debug_info_t *rc = NULL;

695 696 697
	/* Since debugfs currently does not support uid/gid other than root, */
	/* we do not allow gid/uid != 0 until we get support for that. */
	if ((uid != 0) || (gid != 0))
698 699
		pr_warning("Root becomes the owner of all s390dbf files "
			   "in sysfs\n");
S
Stoyan Gaydarov 已提交
700
	BUG_ON(!initialized);
701
	mutex_lock(&debug_mutex);
L
Linus Torvalds 已提交
702 703 704

        /* create new debug_info */

705
	rc = debug_info_create(name, pages_per_area, nr_areas, buf_size, mode);
L
Linus Torvalds 已提交
706 707 708 709
	if(!rc) 
		goto out;
	debug_register_view(rc, &debug_level_view);
        debug_register_view(rc, &debug_flush_view);
710 711 712
	debug_register_view(rc, &debug_pages_view);
out:
        if (!rc){
713
		pr_err("Registering debug feature %s failed\n", name);
L
Linus Torvalds 已提交
714
        }
715
	mutex_unlock(&debug_mutex);
L
Linus Torvalds 已提交
716 717
	return rc;
}
718 719 720 721 722 723 724 725
EXPORT_SYMBOL(debug_register_mode);

/*
 * debug_register:
 * - creates and initializes debug area for the caller
 * - returns handle for debug area
 */

726 727
debug_info_t *debug_register(const char *name, int pages_per_area,
			     int nr_areas, int buf_size)
728 729 730 731
{
	return debug_register_mode(name, pages_per_area, nr_areas, buf_size,
				   S_IRUSR | S_IWUSR, 0, 0);
}
L
Linus Torvalds 已提交
732 733 734 735 736 737

/*
 * debug_unregister:
 * - give back debug area
 */

738 739
void
debug_unregister(debug_info_t * id)
L
Linus Torvalds 已提交
740 741 742
{
	if (!id)
		goto out;
743
	mutex_lock(&debug_mutex);
L
Linus Torvalds 已提交
744
	debug_info_put(id);
745
	mutex_unlock(&debug_mutex);
L
Linus Torvalds 已提交
746

747
out:
L
Linus Torvalds 已提交
748 749 750
	return;
}

751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766
/*
 * debug_set_size:
 * - set area size (number of pages) and number of areas
 */
static int
debug_set_size(debug_info_t* id, int nr_areas, int pages_per_area)
{
	unsigned long flags;
	debug_entry_t *** new_areas;
	int rc=0;

	if(!id || (nr_areas <= 0) || (pages_per_area < 0))
		return -EINVAL;
	if(pages_per_area > 0){
		new_areas = debug_areas_alloc(pages_per_area, nr_areas);
		if(!new_areas) {
767 768
			pr_info("Allocating memory for %i pages failed\n",
				pages_per_area);
769 770 771 772 773 774 775 776 777 778 779 780 781 782 783
			rc = -ENOMEM;
			goto out;
		}
	} else {
		new_areas = NULL;
	}
	spin_lock_irqsave(&id->lock,flags);
	debug_areas_free(id);
	id->areas = new_areas;
	id->nr_areas = nr_areas;
	id->pages_per_area = pages_per_area;
	id->active_area = 0;
	memset(id->active_entries,0,sizeof(int)*id->nr_areas);
	memset(id->active_pages, 0, sizeof(int)*id->nr_areas);
	spin_unlock_irqrestore(&id->lock,flags);
784
	pr_info("%s: set new size (%i pages)\n" ,id->name, pages_per_area);
785 786 787 788
out:
	return rc;
}

L
Linus Torvalds 已提交
789 790 791 792 793
/*
 * debug_set_level:
 * - set actual debug level
 */

794 795
void
debug_set_level(debug_info_t* id, int new_level)
L
Linus Torvalds 已提交
796 797 798 799 800 801 802
{
	unsigned long flags;
	if(!id)
		return;	
	spin_lock_irqsave(&id->lock,flags);
        if(new_level == DEBUG_OFF_LEVEL){
                id->level = DEBUG_OFF_LEVEL;
803
		pr_info("%s: switched off\n",id->name);
L
Linus Torvalds 已提交
804
        } else if ((new_level > DEBUG_MAX_LEVEL) || (new_level < 0)) {
805
		pr_info("%s: level %i is out of range (%i - %i)\n",
L
Linus Torvalds 已提交
806 807 808 809 810 811 812 813 814 815 816 817 818
                        id->name, new_level, 0, DEBUG_MAX_LEVEL);
        } else {
                id->level = new_level;
        }
	spin_unlock_irqrestore(&id->lock,flags);
}


/*
 * proceed_active_entry:
 * - set active entry to next in the ring buffer
 */

819
static inline void
820
proceed_active_entry(debug_info_t * id)
L
Linus Torvalds 已提交
821
{
822 823 824 825 826 827 828
	if ((id->active_entries[id->active_area] += id->entry_size)
	    > (PAGE_SIZE - id->entry_size)){
		id->active_entries[id->active_area] = 0;
		id->active_pages[id->active_area] =
			(id->active_pages[id->active_area] + 1) %
			id->pages_per_area;
	}
L
Linus Torvalds 已提交
829 830 831 832 833 834 835
}

/*
 * proceed_active_area:
 * - set active area to next in the ring buffer
 */

836
static inline void
837
proceed_active_area(debug_info_t * id)
L
Linus Torvalds 已提交
838 839 840 841 842 843 844 845 846
{
	id->active_area++;
	id->active_area = id->active_area % id->nr_areas;
}

/*
 * get_active_entry:
 */

847
static inline debug_entry_t*
848
get_active_entry(debug_info_t * id)
L
Linus Torvalds 已提交
849
{
850 851 852
	return (debug_entry_t *) (((char *) id->areas[id->active_area]
					[id->active_pages[id->active_area]]) +
					id->active_entries[id->active_area]);
L
Linus Torvalds 已提交
853 854 855 856 857 858 859
}

/*
 * debug_finish_entry:
 * - set timestamp, caller address, cpu number etc.
 */

860
static inline void
861 862
debug_finish_entry(debug_info_t * id, debug_entry_t* active, int level,
			int exception)
L
Linus Torvalds 已提交
863
{
864
	active->id.stck = get_clock();
L
Linus Torvalds 已提交
865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884
	active->id.fields.cpuid = smp_processor_id();
	active->caller = __builtin_return_address(0);
	active->id.fields.exception = exception;
	active->id.fields.level     = level;
	proceed_active_entry(id);
	if(exception)
		proceed_active_area(id);
}

static int debug_stoppable=1;
static int debug_active=1;

#define CTL_S390DBF_STOPPABLE 5678
#define CTL_S390DBF_ACTIVE 5679

/*
 * proc handler for the running debug_active sysctl
 * always allow read, allow write only if debug_stoppable is set or
 * if debug_active is already off
 */
885
static int
886
s390dbf_procactive(ctl_table *table, int write,
L
Linus Torvalds 已提交
887 888 889
                     void __user *buffer, size_t *lenp, loff_t *ppos)
{
	if (!write || debug_stoppable || !debug_active)
890
		return proc_dointvec(table, write, buffer, lenp, ppos);
L
Linus Torvalds 已提交
891 892 893 894 895 896 897 898 899 900 901
	else
		return 0;
}


static struct ctl_table s390dbf_table[] = {
	{
		.procname       = "debug_stoppable",
		.data		= &debug_stoppable,
		.maxlen		= sizeof(int),
		.mode           = S_IRUGO | S_IWUSR,
902
		.proc_handler   = proc_dointvec,
L
Linus Torvalds 已提交
903 904 905 906 907 908
	},
	 {
		.procname       = "debug_active",
		.data		= &debug_active,
		.maxlen		= sizeof(int),
		.mode           = S_IRUGO | S_IWUSR,
909
		.proc_handler   = s390dbf_procactive,
L
Linus Torvalds 已提交
910
	},
911
	{ }
L
Linus Torvalds 已提交
912 913 914 915 916 917 918 919 920
};

static struct ctl_table s390dbf_dir_table[] = {
	{
		.procname       = "s390dbf",
		.maxlen         = 0,
		.mode           = S_IRUGO | S_IXUGO,
		.child          = s390dbf_table,
	},
921
	{ }
L
Linus Torvalds 已提交
922 923
};

924
static struct ctl_table_header *s390dbf_sysctl_header;
L
Linus Torvalds 已提交
925

926 927
void
debug_stop_all(void)
L
Linus Torvalds 已提交
928 929 930 931 932 933 934 935 936 937 938
{
	if (debug_stoppable)
		debug_active = 0;
}


/*
 * debug_event_common:
 * - write debug entry with given size
 */

939 940
debug_entry_t*
debug_event_common(debug_info_t * id, int level, const void *buf, int len)
L
Linus Torvalds 已提交
941 942 943 944
{
	unsigned long flags;
	debug_entry_t *active;

945
	if (!debug_active || !id->areas)
L
Linus Torvalds 已提交
946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961
		return NULL;
	spin_lock_irqsave(&id->lock, flags);
	active = get_active_entry(id);
	memset(DEBUG_DATA(active), 0, id->buf_size);
	memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
	debug_finish_entry(id, active, level, 0);
	spin_unlock_irqrestore(&id->lock, flags);

	return active;
}

/*
 * debug_exception_common:
 * - write debug entry with given size and switch to next debug area
 */

962 963
debug_entry_t
*debug_exception_common(debug_info_t * id, int level, const void *buf, int len)
L
Linus Torvalds 已提交
964 965 966 967
{
	unsigned long flags;
	debug_entry_t *active;

968
	if (!debug_active || !id->areas)
L
Linus Torvalds 已提交
969 970 971 972 973 974 975 976 977 978 979 980 981 982 983
		return NULL;
	spin_lock_irqsave(&id->lock, flags);
	active = get_active_entry(id);
	memset(DEBUG_DATA(active), 0, id->buf_size);
	memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
	debug_finish_entry(id, active, level, 1);
	spin_unlock_irqrestore(&id->lock, flags);

	return active;
}

/*
 * counts arguments in format string for sprintf view
 */

984
static inline int
985
debug_count_numargs(char *string)
L
Linus Torvalds 已提交
986 987 988 989 990 991 992 993 994 995 996 997 998 999
{
	int numargs=0;

	while(*string) {
		if(*string++=='%')
			numargs++;
	}
	return(numargs);
}

/*
 * debug_sprintf_event:
 */

1000 1001
debug_entry_t*
debug_sprintf_event(debug_info_t* id, int level,char *string,...)
L
Linus Torvalds 已提交
1002 1003 1004 1005 1006 1007 1008 1009 1010
{
	va_list   ap;
	int numargs,idx;
	unsigned long flags;
	debug_sprintf_entry_t *curr_event;
	debug_entry_t *active;

	if((!id) || (level > id->level))
		return NULL;
1011
	if (!debug_active || !id->areas)
L
Linus Torvalds 已提交
1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032
		return NULL;
	numargs=debug_count_numargs(string);

	spin_lock_irqsave(&id->lock, flags);
	active = get_active_entry(id);
	curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active);
	va_start(ap,string);
	curr_event->string=string;
	for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
		curr_event->args[idx]=va_arg(ap,long);
	va_end(ap);
	debug_finish_entry(id, active, level, 0);
	spin_unlock_irqrestore(&id->lock, flags);

	return active;
}

/*
 * debug_sprintf_exception:
 */

1033 1034
debug_entry_t*
debug_sprintf_exception(debug_info_t* id, int level,char *string,...)
L
Linus Torvalds 已提交
1035 1036 1037 1038 1039 1040 1041 1042 1043
{
	va_list   ap;
	int numargs,idx;
	unsigned long flags;
	debug_sprintf_entry_t *curr_event;
	debug_entry_t *active;

	if((!id) || (level > id->level))
		return NULL;
1044
	if (!debug_active || !id->areas)
L
Linus Torvalds 已提交
1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067
		return NULL;

	numargs=debug_count_numargs(string);

	spin_lock_irqsave(&id->lock, flags);
	active = get_active_entry(id);
	curr_event=(debug_sprintf_entry_t *)DEBUG_DATA(active);
	va_start(ap,string);
	curr_event->string=string;
	for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
		curr_event->args[idx]=va_arg(ap,long);
	va_end(ap);
	debug_finish_entry(id, active, level, 1);
	spin_unlock_irqrestore(&id->lock, flags);

	return active;
}

/*
 * debug_init:
 * - is called exactly once to initialize the debug feature
 */

1068 1069
static int
__init debug_init(void)
L
Linus Torvalds 已提交
1070 1071 1072
{
	int rc = 0;

1073
	s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table);
1074
	mutex_lock(&debug_mutex);
1075
	debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT,NULL);
L
Linus Torvalds 已提交
1076
	initialized = 1;
1077
	mutex_unlock(&debug_mutex);
L
Linus Torvalds 已提交
1078 1079 1080 1081 1082 1083 1084 1085

	return rc;
}

/*
 * debug_register_view:
 */

1086 1087
int
debug_register_view(debug_info_t * id, struct debug_view *view)
L
Linus Torvalds 已提交
1088 1089 1090 1091
{
	int rc = 0;
	int i;
	unsigned long flags;
1092
	mode_t mode;
1093
	struct dentry *pde;
L
Linus Torvalds 已提交
1094 1095 1096

	if (!id)
		goto out;
1097 1098 1099 1100 1101
	mode = (id->mode | S_IFREG) & ~S_IXUGO;
	if (!(view->prolog_proc || view->format_proc || view->header_proc))
		mode &= ~(S_IRUSR | S_IRGRP | S_IROTH);
	if (!view->input_proc)
		mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);
1102
	pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry,
1103
				id , &debug_file_ops);
L
Linus Torvalds 已提交
1104
	if (!pde){
1105 1106
		pr_err("Registering view %s/%s failed due to out of "
		       "memory\n", id->name,view->name);
L
Linus Torvalds 已提交
1107 1108 1109 1110 1111
		rc = -1;
		goto out;
	}
	spin_lock_irqsave(&id->lock, flags);
	for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1112
		if (!id->views[i])
L
Linus Torvalds 已提交
1113 1114 1115
			break;
	}
	if (i == DEBUG_MAX_VIEWS) {
1116 1117
		pr_err("Registering view %s/%s would exceed the maximum "
		       "number of views %i\n", id->name, view->name, i);
1118
		debugfs_remove(pde);
L
Linus Torvalds 已提交
1119
		rc = -1;
1120
	} else {
L
Linus Torvalds 已提交
1121
		id->views[i] = view;
1122
		id->debugfs_entries[i] = pde;
L
Linus Torvalds 已提交
1123 1124
	}
	spin_unlock_irqrestore(&id->lock, flags);
1125
out:
L
Linus Torvalds 已提交
1126 1127 1128 1129 1130 1131 1132
	return rc;
}

/*
 * debug_unregister_view:
 */

1133 1134
int
debug_unregister_view(debug_info_t * id, struct debug_view *view)
L
Linus Torvalds 已提交
1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149
{
	int rc = 0;
	int i;
	unsigned long flags;

	if (!id)
		goto out;
	spin_lock_irqsave(&id->lock, flags);
	for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
		if (id->views[i] == view)
			break;
	}
	if (i == DEBUG_MAX_VIEWS)
		rc = -1;
	else {
1150
		debugfs_remove(id->debugfs_entries[i]);
L
Linus Torvalds 已提交
1151 1152 1153
		id->views[i] = NULL;
	}
	spin_unlock_irqrestore(&id->lock, flags);
1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182
out:
	return rc;
}

static inline char *
debug_get_user_string(const char __user *user_buf, size_t user_len)
{
	char* buffer;

	buffer = kmalloc(user_len + 1, GFP_KERNEL);
	if (!buffer)
		return ERR_PTR(-ENOMEM);
	if (copy_from_user(buffer, user_buf, user_len) != 0) {
		kfree(buffer);
		return ERR_PTR(-EFAULT);
	}
	/* got the string, now strip linefeed. */
	if (buffer[user_len - 1] == '\n')
		buffer[user_len - 1] = 0;
	else
		buffer[user_len] = 0;
        return buffer;
}

static inline int
debug_get_uint(char *buf)
{
	int rc;

1183
	buf = skip_spaces(buf);
1184 1185 1186 1187
	rc = simple_strtoul(buf, &buf, 10);
	if(*buf){
		rc = -EINVAL;
	}
L
Linus Torvalds 已提交
1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199
	return rc;
}

/*
 * functions for debug-views
 ***********************************
*/

/*
 * prints out actual debug level
 */

1200 1201
static int
debug_prolog_pages_fn(debug_info_t * id,
L
Linus Torvalds 已提交
1202
				 struct debug_view *view, char *out_buf)
1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253
{
	return sprintf(out_buf, "%i\n", id->pages_per_area);
}

/*
 * reads new size (number of pages per debug area)
 */

static int
debug_input_pages_fn(debug_info_t * id, struct debug_view *view,
			struct file *file, const char __user *user_buf,
			size_t user_len, loff_t * offset)
{
	char *str;
	int rc,new_pages;

	if (user_len > 0x10000)
                user_len = 0x10000;
	if (*offset != 0){
		rc = -EPIPE;
		goto out;
	}
	str = debug_get_user_string(user_buf,user_len);
	if(IS_ERR(str)){
		rc = PTR_ERR(str);
		goto out;
	}
	new_pages = debug_get_uint(str);
	if(new_pages < 0){
		rc = -EINVAL;
		goto free_str;
	}
	rc = debug_set_size(id,id->nr_areas, new_pages);
	if(rc != 0){
		rc = -EINVAL;
		goto free_str;
	}
	rc = user_len;
free_str:
	kfree(str);
out:
	*offset += user_len;
	return rc;		/* number of input characters */
}

/*
 * prints out actual debug level
 */

static int
debug_prolog_level_fn(debug_info_t * id, struct debug_view *view, char *out_buf)
L
Linus Torvalds 已提交
1254 1255 1256
{
	int rc = 0;

1257 1258 1259 1260 1261 1262
	if(id->level == DEBUG_OFF_LEVEL) {
		rc = sprintf(out_buf,"-\n");
	}
	else {
		rc = sprintf(out_buf, "%i\n", id->level);
	}
L
Linus Torvalds 已提交
1263 1264 1265 1266 1267 1268 1269
	return rc;
}

/*
 * reads new debug level
 */

1270 1271 1272 1273
static int
debug_input_level_fn(debug_info_t * id, struct debug_view *view,
			struct file *file, const char __user *user_buf,
			size_t user_len, loff_t * offset)
L
Linus Torvalds 已提交
1274
{
1275 1276
	char *str;
	int rc,new_level;
L
Linus Torvalds 已提交
1277

1278 1279 1280 1281
	if (user_len > 0x10000)
                user_len = 0x10000;
	if (*offset != 0){
		rc = -EPIPE;
L
Linus Torvalds 已提交
1282
		goto out;
1283 1284 1285 1286
	}
	str = debug_get_user_string(user_buf,user_len);
	if(IS_ERR(str)){
		rc = PTR_ERR(str);
L
Linus Torvalds 已提交
1287 1288
		goto out;
	}
1289
	if(str[0] == '-'){
L
Linus Torvalds 已提交
1290
		debug_set_level(id, DEBUG_OFF_LEVEL);
1291 1292
		rc = user_len;
		goto free_str;
L
Linus Torvalds 已提交
1293
	} else {
1294
		new_level = debug_get_uint(str);
L
Linus Torvalds 已提交
1295
	}
1296
	if(new_level < 0) {
1297 1298
		pr_warning("%s is not a valid level for a debug "
			   "feature\n", str);
1299 1300 1301 1302 1303 1304 1305 1306 1307
		rc = -EINVAL;
	} else {
		debug_set_level(id, new_level);
		rc = user_len;
	}
free_str:
	kfree(str);
out:
	*offset += user_len;
L
Linus Torvalds 已提交
1308 1309 1310 1311 1312 1313 1314 1315
	return rc;		/* number of input characters */
}


/*
 * flushes debug areas
 */
 
1316
static void debug_flush(debug_info_t* id, int area)
L
Linus Torvalds 已提交
1317 1318
{
        unsigned long flags;
1319
        int i,j;
L
Linus Torvalds 已提交
1320

1321
        if(!id || !id->areas)
L
Linus Torvalds 已提交
1322 1323 1324 1325
                return;
        spin_lock_irqsave(&id->lock,flags);
        if(area == DEBUG_FLUSH_ALL){
                id->active_area = 0;
1326 1327 1328 1329 1330 1331 1332
                memset(id->active_entries, 0, id->nr_areas * sizeof(int));
                for (i = 0; i < id->nr_areas; i++) {
			id->active_pages[i] = 0;
			for(j = 0; j < id->pages_per_area; j++) {
                        	memset(id->areas[i][j], 0, PAGE_SIZE);
			}
		}
L
Linus Torvalds 已提交
1333
        } else if(area >= 0 && area < id->nr_areas) {
1334 1335 1336 1337 1338
                id->active_entries[area] = 0;
		id->active_pages[area] = 0;
		for(i = 0; i < id->pages_per_area; i++) {
                	memset(id->areas[area][i],0,PAGE_SIZE);
		}
L
Linus Torvalds 已提交
1339 1340 1341 1342 1343 1344 1345 1346
        }
        spin_unlock_irqrestore(&id->lock,flags);
}

/*
 * view function: flushes debug areas 
 */

1347 1348 1349 1350
static int
debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
			struct file *file, const char __user *user_buf,
			size_t user_len, loff_t * offset)
L
Linus Torvalds 已提交
1351 1352
{
        char input_buf[1];
1353 1354 1355 1356 1357 1358
        int rc = user_len;

	if (user_len > 0x10000)
                user_len = 0x10000;
        if (*offset != 0){
		rc = -EPIPE;
L
Linus Torvalds 已提交
1359
                goto out;
1360
	}
L
Linus Torvalds 已提交
1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374
        if (copy_from_user(input_buf, user_buf, 1)){
                rc = -EFAULT;
                goto out;
        }
        if(input_buf[0] == '-') { 
                debug_flush(id, DEBUG_FLUSH_ALL);
                goto out;
        }
        if (isdigit(input_buf[0])) {
                int area = ((int) input_buf[0] - (int) '0');
                debug_flush(id, area);
                goto out;
        }

1375 1376
	pr_info("Flushing debug data failed because %c is not a valid "
		 "area\n", input_buf[0]);
L
Linus Torvalds 已提交
1377

1378 1379
out:
        *offset += user_len;
L
Linus Torvalds 已提交
1380 1381 1382 1383 1384 1385 1386
        return rc;              /* number of input characters */
}

/*
 * prints debug header in raw format
 */

1387 1388 1389
static int
debug_raw_header_fn(debug_info_t * id, struct debug_view *view,
			int area, debug_entry_t * entry, char *out_buf)
L
Linus Torvalds 已提交
1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401
{
        int rc;

	rc = sizeof(debug_entry_t);
	memcpy(out_buf,entry,sizeof(debug_entry_t));
        return rc;
}

/*
 * prints debug data in raw format
 */

1402 1403
static int
debug_raw_format_fn(debug_info_t * id, struct debug_view *view,
L
Linus Torvalds 已提交
1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416
			       char *out_buf, const char *in_buf)
{
	int rc;

	rc = id->buf_size;
	memcpy(out_buf, in_buf, id->buf_size);
	return rc;
}

/*
 * prints debug data in hex/ascii format
 */

1417 1418 1419
static int
debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
	    		  char *out_buf, const char *in_buf)
L
Linus Torvalds 已提交
1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442
{
	int i, rc = 0;

	for (i = 0; i < id->buf_size; i++) {
                rc += sprintf(out_buf + rc, "%02x ",
                              ((unsigned char *) in_buf)[i]);
        }
	rc += sprintf(out_buf + rc, "| ");
	for (i = 0; i < id->buf_size; i++) {
		unsigned char c = in_buf[i];
		if (!isprint(c))
			rc += sprintf(out_buf + rc, ".");
		else
			rc += sprintf(out_buf + rc, "%c", c);
	}
	rc += sprintf(out_buf + rc, "\n");
	return rc;
}

/*
 * prints header for debug entry
 */

1443 1444
int
debug_dflt_header_fn(debug_info_t * id, struct debug_view *view,
L
Linus Torvalds 已提交
1445 1446
			 int area, debug_entry_t * entry, char *out_buf)
{
1447
	struct timespec time_spec;
L
Linus Torvalds 已提交
1448 1449 1450 1451 1452 1453
	char *except_str;
	unsigned long caller;
	int rc = 0;
	unsigned int level;

	level = entry->id.fields.level;
1454
	stck_to_timespec(entry->id.stck, &time_spec);
L
Linus Torvalds 已提交
1455 1456 1457 1458 1459 1460 1461

	if (entry->id.fields.exception)
		except_str = "*";
	else
		except_str = "-";
	caller = ((unsigned long) entry->caller) & PSW_ADDR_INSN;
	rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %p  ",
1462
		      area, time_spec.tv_sec, time_spec.tv_nsec / 1000, level,
L
Linus Torvalds 已提交
1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473
		      except_str, entry->id.fields.cpuid, (void *) caller);
	return rc;
}

/*
 * prints debug data sprintf-formated:
 * debug_sprinf_event/exception calls must be used together with this view
 */

#define DEBUG_SPRINTF_MAX_ARGS 10

1474 1475 1476
static int
debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view,
                        char *out_buf, debug_sprintf_entry_t *curr_event)
L
Linus Torvalds 已提交
1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515
{
	int num_longs, num_used_args = 0,i, rc = 0;
	int index[DEBUG_SPRINTF_MAX_ARGS];

	/* count of longs fit into one entry */
	num_longs = id->buf_size /  sizeof(long); 

	if(num_longs < 1)
		goto out; /* bufsize of entry too small */
	if(num_longs == 1) {
		/* no args, we use only the string */
		strcpy(out_buf, curr_event->string);
		rc = strlen(curr_event->string);
		goto out;
	}

	/* number of arguments used for sprintf (without the format string) */
	num_used_args   = min(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1));

	memset(index,0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int));

	for(i = 0; i < num_used_args; i++)
		index[i] = i;

	rc =  sprintf(out_buf, curr_event->string, curr_event->args[index[0]],
		curr_event->args[index[1]], curr_event->args[index[2]],
		curr_event->args[index[3]], curr_event->args[index[4]],
		curr_event->args[index[5]], curr_event->args[index[6]],
		curr_event->args[index[7]], curr_event->args[index[8]],
		curr_event->args[index[9]]);

out:

	return rc;
}

/*
 * clean up module
 */
1516
static void __exit debug_exit(void)
L
Linus Torvalds 已提交
1517
{
1518
	debugfs_remove(debug_debugfs_root_entry);
L
Linus Torvalds 已提交
1519 1520 1521 1522 1523 1524 1525
	unregister_sysctl_table(s390dbf_sysctl_header);
	return;
}

/*
 * module definitions
 */
1526
postcore_initcall(debug_init);
L
Linus Torvalds 已提交
1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543
module_exit(debug_exit);
MODULE_LICENSE("GPL");

EXPORT_SYMBOL(debug_register);
EXPORT_SYMBOL(debug_unregister); 
EXPORT_SYMBOL(debug_set_level);
EXPORT_SYMBOL(debug_stop_all);
EXPORT_SYMBOL(debug_register_view);
EXPORT_SYMBOL(debug_unregister_view);
EXPORT_SYMBOL(debug_event_common);
EXPORT_SYMBOL(debug_exception_common);
EXPORT_SYMBOL(debug_hex_ascii_view);
EXPORT_SYMBOL(debug_raw_view);
EXPORT_SYMBOL(debug_dflt_header_fn);
EXPORT_SYMBOL(debug_sprintf_view);
EXPORT_SYMBOL(debug_sprintf_exception);
EXPORT_SYMBOL(debug_sprintf_event);