1 /*
2  *  arch/s390/kernel/debug.c
3  *   S/390 debug facility
4  *
5  *    Copyright (C) 1999, 2000 IBM Deutschland Entwicklung GmbH,
6  *                             IBM Corporation
7  *    Author(s): Michael Holzheu (holzheu@de.ibm.com),
8  *               Holger Smolinski (Holger.Smolinski@de.ibm.com)
9  *
10  *    Bugreports to: <Linux390@de.ibm.com>
11  */
12 
13 #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, mode_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 
171 static const struct file_operations debug_file_ops = {
172 	.owner   = THIS_MODULE,
173 	.read    = debug_output,
174 	.write   = debug_input,
175 	.open    = debug_open,
176 	.release = debug_close,
177 	.llseek  = no_llseek,
178 };
179 
180 static struct dentry *debug_debugfs_root_entry;
181 
182 /* functions */
183 
184 /*
185  * debug_areas_alloc
186  * - Debug areas are implemented as a threedimensonal array:
187  *   areas[areanumber][pagenumber][pageoffset]
188  */
189 
190 static debug_entry_t***
debug_areas_alloc(int pages_per_area,int nr_areas)191 debug_areas_alloc(int pages_per_area, int nr_areas)
192 {
193 	debug_entry_t*** areas;
194 	int i,j;
195 
196 	areas = kmalloc(nr_areas *
197 					sizeof(debug_entry_t**),
198 					GFP_KERNEL);
199 	if (!areas)
200 		goto fail_malloc_areas;
201 	for (i = 0; i < nr_areas; i++) {
202 		areas[i] = kmalloc(pages_per_area *
203 				sizeof(debug_entry_t*),GFP_KERNEL);
204 		if (!areas[i]) {
205 			goto fail_malloc_areas2;
206 		}
207 		for(j = 0; j < pages_per_area; j++) {
208 			areas[i][j] = kzalloc(PAGE_SIZE, GFP_KERNEL);
209 			if(!areas[i][j]) {
210 				for(j--; j >=0 ; j--) {
211 					kfree(areas[i][j]);
212 				}
213 				kfree(areas[i]);
214 				goto fail_malloc_areas2;
215 			}
216 		}
217 	}
218 	return areas;
219 
220 fail_malloc_areas2:
221 	for(i--; i >= 0; i--){
222 		for(j=0; j < pages_per_area;j++){
223 			kfree(areas[i][j]);
224 		}
225 		kfree(areas[i]);
226 	}
227 	kfree(areas);
228 fail_malloc_areas:
229 	return NULL;
230 
231 }
232 
233 
234 /*
235  * debug_info_alloc
236  * - alloc new debug-info
237  */
238 
239 static debug_info_t*
debug_info_alloc(const char * name,int pages_per_area,int nr_areas,int buf_size,int level,int mode)240 debug_info_alloc(const char *name, int pages_per_area, int nr_areas,
241 		 int buf_size, int level, int mode)
242 {
243 	debug_info_t* rc;
244 
245 	/* alloc everything */
246 
247 	rc = kmalloc(sizeof(debug_info_t), GFP_KERNEL);
248 	if(!rc)
249 		goto fail_malloc_rc;
250 	rc->active_entries = kcalloc(nr_areas, sizeof(int), GFP_KERNEL);
251 	if(!rc->active_entries)
252 		goto fail_malloc_active_entries;
253 	rc->active_pages = kcalloc(nr_areas, sizeof(int), GFP_KERNEL);
254 	if(!rc->active_pages)
255 		goto fail_malloc_active_pages;
256 	if((mode == ALL_AREAS) && (pages_per_area != 0)){
257 		rc->areas = debug_areas_alloc(pages_per_area, nr_areas);
258 		if(!rc->areas)
259 			goto fail_malloc_areas;
260 	} else {
261 		rc->areas = NULL;
262 	}
263 
264 	/* initialize members */
265 
266 	spin_lock_init(&rc->lock);
267 	rc->pages_per_area = pages_per_area;
268 	rc->nr_areas       = nr_areas;
269 	rc->active_area    = 0;
270 	rc->level          = level;
271 	rc->buf_size       = buf_size;
272 	rc->entry_size     = sizeof(debug_entry_t) + buf_size;
273 	strlcpy(rc->name, name, sizeof(rc->name));
274 	memset(rc->views, 0, DEBUG_MAX_VIEWS * sizeof(struct debug_view *));
275 	memset(rc->debugfs_entries, 0 ,DEBUG_MAX_VIEWS *
276 		sizeof(struct dentry*));
277 	atomic_set(&(rc->ref_count), 0);
278 
279 	return rc;
280 
281 fail_malloc_areas:
282 	kfree(rc->active_pages);
283 fail_malloc_active_pages:
284 	kfree(rc->active_entries);
285 fail_malloc_active_entries:
286 	kfree(rc);
287 fail_malloc_rc:
288 	return NULL;
289 }
290 
291 /*
292  * debug_areas_free
293  * - free all debug areas
294  */
295 
296 static void
debug_areas_free(debug_info_t * db_info)297 debug_areas_free(debug_info_t* db_info)
298 {
299 	int i,j;
300 
301 	if(!db_info->areas)
302 		return;
303 	for (i = 0; i < db_info->nr_areas; i++) {
304 		for(j = 0; j < db_info->pages_per_area; j++) {
305 			kfree(db_info->areas[i][j]);
306 		}
307 		kfree(db_info->areas[i]);
308 	}
309 	kfree(db_info->areas);
310 	db_info->areas = NULL;
311 }
312 
313 /*
314  * debug_info_free
315  * - free memory debug-info
316  */
317 
318 static void
debug_info_free(debug_info_t * db_info)319 debug_info_free(debug_info_t* db_info){
320 	debug_areas_free(db_info);
321 	kfree(db_info->active_entries);
322 	kfree(db_info->active_pages);
323 	kfree(db_info);
324 }
325 
326 /*
327  * debug_info_create
328  * - create new debug-info
329  */
330 
331 static debug_info_t*
debug_info_create(const char * name,int pages_per_area,int nr_areas,int buf_size,mode_t mode)332 debug_info_create(const char *name, int pages_per_area, int nr_areas,
333 		  int buf_size, mode_t mode)
334 {
335 	debug_info_t* rc;
336 
337         rc = debug_info_alloc(name, pages_per_area, nr_areas, buf_size,
338 				DEBUG_DEFAULT_LEVEL, ALL_AREAS);
339         if(!rc)
340 		goto out;
341 
342 	rc->mode = mode & ~S_IFMT;
343 
344 	/* create root directory */
345         rc->debugfs_root_entry = debugfs_create_dir(rc->name,
346 					debug_debugfs_root_entry);
347 
348 	/* append new element to linked list */
349         if (!debug_area_first) {
350                 /* first element in list */
351                 debug_area_first = rc;
352                 rc->prev = NULL;
353         } else {
354                 /* append element to end of list */
355                 debug_area_last->next = rc;
356                 rc->prev = debug_area_last;
357         }
358         debug_area_last = rc;
359         rc->next = NULL;
360 
361 	debug_info_get(rc);
362 out:
363 	return rc;
364 }
365 
366 /*
367  * debug_info_copy
368  * - copy debug-info
369  */
370 
371 static debug_info_t*
debug_info_copy(debug_info_t * in,int mode)372 debug_info_copy(debug_info_t* in, int mode)
373 {
374         int i,j;
375         debug_info_t* rc;
376         unsigned long flags;
377 
378 	/* get a consistent copy of the debug areas */
379 	do {
380 		rc = debug_info_alloc(in->name, in->pages_per_area,
381 			in->nr_areas, in->buf_size, in->level, mode);
382 		spin_lock_irqsave(&in->lock, flags);
383 		if(!rc)
384 			goto out;
385 		/* has something changed in the meantime ? */
386 		if((rc->pages_per_area == in->pages_per_area) &&
387 		   (rc->nr_areas == in->nr_areas)) {
388 			break;
389 		}
390 		spin_unlock_irqrestore(&in->lock, flags);
391 		debug_info_free(rc);
392 	} while (1);
393 
394 	if (mode == NO_AREAS)
395                 goto out;
396 
397         for(i = 0; i < in->nr_areas; i++){
398 		for(j = 0; j < in->pages_per_area; j++) {
399 			memcpy(rc->areas[i][j], in->areas[i][j],PAGE_SIZE);
400 		}
401         }
402 out:
403         spin_unlock_irqrestore(&in->lock, flags);
404         return rc;
405 }
406 
407 /*
408  * debug_info_get
409  * - increments reference count for debug-info
410  */
411 
412 static void
debug_info_get(debug_info_t * db_info)413 debug_info_get(debug_info_t * db_info)
414 {
415 	if (db_info)
416 		atomic_inc(&db_info->ref_count);
417 }
418 
419 /*
420  * debug_info_put:
421  * - decreases reference count for debug-info and frees it if necessary
422  */
423 
424 static void
debug_info_put(debug_info_t * db_info)425 debug_info_put(debug_info_t *db_info)
426 {
427 	int i;
428 
429 	if (!db_info)
430 		return;
431 	if (atomic_dec_and_test(&db_info->ref_count)) {
432 		for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
433 			if (!db_info->views[i])
434 				continue;
435 			debugfs_remove(db_info->debugfs_entries[i]);
436 		}
437 		debugfs_remove(db_info->debugfs_root_entry);
438 		if(db_info == debug_area_first)
439 			debug_area_first = db_info->next;
440 		if(db_info == debug_area_last)
441 			debug_area_last = db_info->prev;
442 		if(db_info->prev) db_info->prev->next = db_info->next;
443 		if(db_info->next) db_info->next->prev = db_info->prev;
444 		debug_info_free(db_info);
445 	}
446 }
447 
448 /*
449  * debug_format_entry:
450  * - format one debug entry and return size of formated data
451  */
452 
453 static int
debug_format_entry(file_private_info_t * p_info)454 debug_format_entry(file_private_info_t *p_info)
455 {
456 	debug_info_t *id_snap   = p_info->debug_info_snap;
457 	struct debug_view *view = p_info->view;
458 	debug_entry_t *act_entry;
459 	size_t len = 0;
460 	if(p_info->act_entry == DEBUG_PROLOG_ENTRY){
461 		/* print prolog */
462         	if (view->prolog_proc)
463                 	len += view->prolog_proc(id_snap,view,p_info->temp_buf);
464 		goto out;
465 	}
466 	if (!id_snap->areas) /* this is true, if we have a prolog only view */
467 		goto out;    /* or if 'pages_per_area' is 0 */
468 	act_entry = (debug_entry_t *) ((char*)id_snap->areas[p_info->act_area]
469 				[p_info->act_page] + p_info->act_entry);
470 
471 	if (act_entry->id.stck == 0LL)
472 			goto out;  /* empty entry */
473 	if (view->header_proc)
474 		len += view->header_proc(id_snap, view, p_info->act_area,
475 					act_entry, p_info->temp_buf + len);
476 	if (view->format_proc)
477 		len += view->format_proc(id_snap, view, p_info->temp_buf + len,
478 						DEBUG_DATA(act_entry));
479 out:
480         return len;
481 }
482 
483 /*
484  * debug_next_entry:
485  * - goto next entry in p_info
486  */
487 
488 static inline int
debug_next_entry(file_private_info_t * p_info)489 debug_next_entry(file_private_info_t *p_info)
490 {
491 	debug_info_t *id;
492 
493 	id = p_info->debug_info_snap;
494 	if(p_info->act_entry == DEBUG_PROLOG_ENTRY){
495 		p_info->act_entry = 0;
496 		p_info->act_page  = 0;
497 		goto out;
498 	}
499 	if(!id->areas)
500 		return 1;
501 	p_info->act_entry += id->entry_size;
502 	/* switch to next page, if we reached the end of the page  */
503 	if (p_info->act_entry > (PAGE_SIZE - id->entry_size)){
504 		/* next page */
505 		p_info->act_entry = 0;
506 		p_info->act_page += 1;
507 		if((p_info->act_page % id->pages_per_area) == 0) {
508 			/* next area */
509         		p_info->act_area++;
510 			p_info->act_page=0;
511 		}
512         	if(p_info->act_area >= id->nr_areas)
513 			return 1;
514 	}
515 out:
516 	return 0;
517 }
518 
519 /*
520  * debug_output:
521  * - called for user read()
522  * - copies formated debug entries to the user buffer
523  */
524 
525 static ssize_t
debug_output(struct file * file,char __user * user_buf,size_t len,loff_t * offset)526 debug_output(struct file *file,		/* file descriptor */
527 	    char __user *user_buf,	/* user buffer */
528 	    size_t  len,		/* length of buffer */
529 	    loff_t *offset)		/* offset in the file */
530 {
531 	size_t count = 0;
532 	size_t entry_offset;
533 	file_private_info_t *p_info;
534 
535 	p_info = ((file_private_info_t *) file->private_data);
536 	if (*offset != p_info->offset)
537 		return -EPIPE;
538 	if(p_info->act_area >= p_info->debug_info_snap->nr_areas)
539 		return 0;
540 	entry_offset = p_info->act_entry_offset;
541 	while(count < len){
542 		int formatted_line_size;
543 		int formatted_line_residue;
544 		int user_buf_residue;
545 		size_t copy_size;
546 
547 		formatted_line_size = debug_format_entry(p_info);
548 		formatted_line_residue = formatted_line_size - entry_offset;
549 		user_buf_residue = len-count;
550 		copy_size = min(user_buf_residue, formatted_line_residue);
551 		if(copy_size){
552 			if (copy_to_user(user_buf + count, p_info->temp_buf
553 					+ entry_offset, copy_size))
554 				return -EFAULT;
555 			count += copy_size;
556 			entry_offset += copy_size;
557 		}
558 		if(copy_size == formatted_line_residue){
559 			entry_offset = 0;
560 			if(debug_next_entry(p_info))
561 				goto out;
562 		}
563 	}
564 out:
565 	p_info->offset           = *offset + count;
566 	p_info->act_entry_offset = entry_offset;
567 	*offset = p_info->offset;
568 	return count;
569 }
570 
571 /*
572  * debug_input:
573  * - called for user write()
574  * - calls input function of view
575  */
576 
577 static ssize_t
debug_input(struct file * file,const char __user * user_buf,size_t length,loff_t * offset)578 debug_input(struct file *file, const char __user *user_buf, size_t length,
579 		loff_t *offset)
580 {
581 	int rc = 0;
582 	file_private_info_t *p_info;
583 
584 	mutex_lock(&debug_mutex);
585 	p_info = ((file_private_info_t *) file->private_data);
586 	if (p_info->view->input_proc)
587 		rc = p_info->view->input_proc(p_info->debug_info_org,
588 					      p_info->view, file, user_buf,
589 					      length, offset);
590 	else
591 		rc = -EPERM;
592 	mutex_unlock(&debug_mutex);
593 	return rc;		/* number of input characters */
594 }
595 
596 /*
597  * debug_open:
598  * - called for user open()
599  * - copies formated output to private_data area of the file
600  *   handle
601  */
602 
603 static int
debug_open(struct inode * inode,struct file * file)604 debug_open(struct inode *inode, struct file *file)
605 {
606 	int i, rc = 0;
607 	file_private_info_t *p_info;
608 	debug_info_t *debug_info, *debug_info_snapshot;
609 
610 	mutex_lock(&debug_mutex);
611 	debug_info = file->f_path.dentry->d_inode->i_private;
612 	/* find debug view */
613 	for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
614 		if (!debug_info->views[i])
615 			continue;
616 		else if (debug_info->debugfs_entries[i] ==
617 			 file->f_path.dentry) {
618 			goto found;	/* found view ! */
619 		}
620 	}
621 	/* no entry found */
622 	rc = -EINVAL;
623 	goto out;
624 
625 found:
626 
627 	/* Make snapshot of current debug areas to get it consistent.     */
628 	/* To copy all the areas is only needed, if we have a view which  */
629 	/* formats the debug areas. */
630 
631 	if(!debug_info->views[i]->format_proc &&
632 		!debug_info->views[i]->header_proc){
633 		debug_info_snapshot = debug_info_copy(debug_info, NO_AREAS);
634 	} else {
635 		debug_info_snapshot = debug_info_copy(debug_info, ALL_AREAS);
636 	}
637 
638 	if(!debug_info_snapshot){
639 		rc = -ENOMEM;
640 		goto out;
641 	}
642 	p_info = kmalloc(sizeof(file_private_info_t),
643 						GFP_KERNEL);
644 	if(!p_info){
645 		debug_info_free(debug_info_snapshot);
646 		rc = -ENOMEM;
647 		goto out;
648 	}
649 	p_info->offset = 0;
650 	p_info->debug_info_snap = debug_info_snapshot;
651 	p_info->debug_info_org  = debug_info;
652 	p_info->view = debug_info->views[i];
653 	p_info->act_area = 0;
654 	p_info->act_page = 0;
655 	p_info->act_entry = DEBUG_PROLOG_ENTRY;
656 	p_info->act_entry_offset = 0;
657 	file->private_data = p_info;
658 	debug_info_get(debug_info);
659 	nonseekable_open(inode, file);
660 out:
661 	mutex_unlock(&debug_mutex);
662 	return rc;
663 }
664 
665 /*
666  * debug_close:
667  * - called for user close()
668  * - deletes  private_data area of the file handle
669  */
670 
671 static int
debug_close(struct inode * inode,struct file * file)672 debug_close(struct inode *inode, struct file *file)
673 {
674 	file_private_info_t *p_info;
675 	p_info = (file_private_info_t *) file->private_data;
676 	if(p_info->debug_info_snap)
677 		debug_info_free(p_info->debug_info_snap);
678 	debug_info_put(p_info->debug_info_org);
679 	kfree(file->private_data);
680 	return 0;		/* success */
681 }
682 
683 /*
684  * debug_register_mode:
685  * - Creates and initializes debug area for the caller
686  *   The mode parameter allows to specify access rights for the s390dbf files
687  * - Returns handle for debug area
688  */
689 
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)690 debug_info_t *debug_register_mode(const char *name, int pages_per_area,
691 				  int nr_areas, int buf_size, mode_t mode,
692 				  uid_t uid, gid_t gid)
693 {
694 	debug_info_t *rc = NULL;
695 
696 	/* Since debugfs currently does not support uid/gid other than root, */
697 	/* we do not allow gid/uid != 0 until we get support for that. */
698 	if ((uid != 0) || (gid != 0))
699 		pr_warning("Root becomes the owner of all s390dbf files "
700 			   "in sysfs\n");
701 	BUG_ON(!initialized);
702 	mutex_lock(&debug_mutex);
703 
704         /* create new debug_info */
705 
706 	rc = debug_info_create(name, pages_per_area, nr_areas, buf_size, mode);
707 	if(!rc)
708 		goto out;
709 	debug_register_view(rc, &debug_level_view);
710         debug_register_view(rc, &debug_flush_view);
711 	debug_register_view(rc, &debug_pages_view);
712 out:
713         if (!rc){
714 		pr_err("Registering debug feature %s failed\n", name);
715         }
716 	mutex_unlock(&debug_mutex);
717 	return rc;
718 }
719 EXPORT_SYMBOL(debug_register_mode);
720 
721 /*
722  * debug_register:
723  * - creates and initializes debug area for the caller
724  * - returns handle for debug area
725  */
726 
debug_register(const char * name,int pages_per_area,int nr_areas,int buf_size)727 debug_info_t *debug_register(const char *name, int pages_per_area,
728 			     int nr_areas, int buf_size)
729 {
730 	return debug_register_mode(name, pages_per_area, nr_areas, buf_size,
731 				   S_IRUSR | S_IWUSR, 0, 0);
732 }
733 
734 /*
735  * debug_unregister:
736  * - give back debug area
737  */
738 
739 void
debug_unregister(debug_info_t * id)740 debug_unregister(debug_info_t * id)
741 {
742 	if (!id)
743 		goto out;
744 	mutex_lock(&debug_mutex);
745 	debug_info_put(id);
746 	mutex_unlock(&debug_mutex);
747 
748 out:
749 	return;
750 }
751 
752 /*
753  * debug_set_size:
754  * - set area size (number of pages) and number of areas
755  */
756 static int
debug_set_size(debug_info_t * id,int nr_areas,int pages_per_area)757 debug_set_size(debug_info_t* id, int nr_areas, int pages_per_area)
758 {
759 	unsigned long flags;
760 	debug_entry_t *** new_areas;
761 	int rc=0;
762 
763 	if(!id || (nr_areas <= 0) || (pages_per_area < 0))
764 		return -EINVAL;
765 	if(pages_per_area > 0){
766 		new_areas = debug_areas_alloc(pages_per_area, nr_areas);
767 		if(!new_areas) {
768 			pr_info("Allocating memory for %i pages failed\n",
769 				pages_per_area);
770 			rc = -ENOMEM;
771 			goto out;
772 		}
773 	} else {
774 		new_areas = NULL;
775 	}
776 	spin_lock_irqsave(&id->lock,flags);
777 	debug_areas_free(id);
778 	id->areas = new_areas;
779 	id->nr_areas = nr_areas;
780 	id->pages_per_area = pages_per_area;
781 	id->active_area = 0;
782 	memset(id->active_entries,0,sizeof(int)*id->nr_areas);
783 	memset(id->active_pages, 0, sizeof(int)*id->nr_areas);
784 	spin_unlock_irqrestore(&id->lock,flags);
785 	pr_info("%s: set new size (%i pages)\n" ,id->name, pages_per_area);
786 out:
787 	return rc;
788 }
789 
790 /*
791  * debug_set_level:
792  * - set actual debug level
793  */
794 
795 void
debug_set_level(debug_info_t * id,int new_level)796 debug_set_level(debug_info_t* id, int new_level)
797 {
798 	unsigned long flags;
799 	if(!id)
800 		return;
801 	spin_lock_irqsave(&id->lock,flags);
802         if(new_level == DEBUG_OFF_LEVEL){
803                 id->level = DEBUG_OFF_LEVEL;
804 		pr_info("%s: switched off\n",id->name);
805         } else if ((new_level > DEBUG_MAX_LEVEL) || (new_level < 0)) {
806 		pr_info("%s: level %i is out of range (%i - %i)\n",
807                         id->name, new_level, 0, DEBUG_MAX_LEVEL);
808         } else {
809                 id->level = new_level;
810         }
811 	spin_unlock_irqrestore(&id->lock,flags);
812 }
813 
814 
815 /*
816  * proceed_active_entry:
817  * - set active entry to next in the ring buffer
818  */
819 
820 static inline void
proceed_active_entry(debug_info_t * id)821 proceed_active_entry(debug_info_t * id)
822 {
823 	if ((id->active_entries[id->active_area] += id->entry_size)
824 	    > (PAGE_SIZE - id->entry_size)){
825 		id->active_entries[id->active_area] = 0;
826 		id->active_pages[id->active_area] =
827 			(id->active_pages[id->active_area] + 1) %
828 			id->pages_per_area;
829 	}
830 }
831 
832 /*
833  * proceed_active_area:
834  * - set active area to next in the ring buffer
835  */
836 
837 static inline void
proceed_active_area(debug_info_t * id)838 proceed_active_area(debug_info_t * id)
839 {
840 	id->active_area++;
841 	id->active_area = id->active_area % id->nr_areas;
842 }
843 
844 /*
845  * get_active_entry:
846  */
847 
848 static inline debug_entry_t*
get_active_entry(debug_info_t * id)849 get_active_entry(debug_info_t * id)
850 {
851 	return (debug_entry_t *) (((char *) id->areas[id->active_area]
852 					[id->active_pages[id->active_area]]) +
853 					id->active_entries[id->active_area]);
854 }
855 
856 /*
857  * debug_finish_entry:
858  * - set timestamp, caller address, cpu number etc.
859  */
860 
861 static inline void
debug_finish_entry(debug_info_t * id,debug_entry_t * active,int level,int exception)862 debug_finish_entry(debug_info_t * id, debug_entry_t* active, int level,
863 			int exception)
864 {
865 	active->id.stck = get_clock();
866 	active->id.fields.cpuid = smp_processor_id();
867 	active->caller = __builtin_return_address(0);
868 	active->id.fields.exception = exception;
869 	active->id.fields.level     = level;
870 	proceed_active_entry(id);
871 	if(exception)
872 		proceed_active_area(id);
873 }
874 
875 static int debug_stoppable=1;
876 static int debug_active=1;
877 
878 #define CTL_S390DBF_STOPPABLE 5678
879 #define CTL_S390DBF_ACTIVE 5679
880 
881 /*
882  * proc handler for the running debug_active sysctl
883  * always allow read, allow write only if debug_stoppable is set or
884  * if debug_active is already off
885  */
886 static int
s390dbf_procactive(ctl_table * table,int write,void __user * buffer,size_t * lenp,loff_t * ppos)887 s390dbf_procactive(ctl_table *table, int write,
888                      void __user *buffer, size_t *lenp, loff_t *ppos)
889 {
890 	if (!write || debug_stoppable || !debug_active)
891 		return proc_dointvec(table, write, buffer, lenp, ppos);
892 	else
893 		return 0;
894 }
895 
896 
897 static struct ctl_table s390dbf_table[] = {
898 	{
899 		.procname       = "debug_stoppable",
900 		.data		= &debug_stoppable,
901 		.maxlen		= sizeof(int),
902 		.mode           = S_IRUGO | S_IWUSR,
903 		.proc_handler   = proc_dointvec,
904 	},
905 	 {
906 		.procname       = "debug_active",
907 		.data		= &debug_active,
908 		.maxlen		= sizeof(int),
909 		.mode           = S_IRUGO | S_IWUSR,
910 		.proc_handler   = s390dbf_procactive,
911 	},
912 	{ }
913 };
914 
915 static struct ctl_table s390dbf_dir_table[] = {
916 	{
917 		.procname       = "s390dbf",
918 		.maxlen         = 0,
919 		.mode           = S_IRUGO | S_IXUGO,
920 		.child          = s390dbf_table,
921 	},
922 	{ }
923 };
924 
925 static struct ctl_table_header *s390dbf_sysctl_header;
926 
927 void
debug_stop_all(void)928 debug_stop_all(void)
929 {
930 	if (debug_stoppable)
931 		debug_active = 0;
932 }
933 
934 
935 /*
936  * debug_event_common:
937  * - write debug entry with given size
938  */
939 
940 debug_entry_t*
debug_event_common(debug_info_t * id,int level,const void * buf,int len)941 debug_event_common(debug_info_t * id, int level, const void *buf, int len)
942 {
943 	unsigned long flags;
944 	debug_entry_t *active;
945 
946 	if (!debug_active || !id->areas)
947 		return NULL;
948 	spin_lock_irqsave(&id->lock, flags);
949 	active = get_active_entry(id);
950 	memset(DEBUG_DATA(active), 0, id->buf_size);
951 	memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
952 	debug_finish_entry(id, active, level, 0);
953 	spin_unlock_irqrestore(&id->lock, flags);
954 
955 	return active;
956 }
957 
958 /*
959  * debug_exception_common:
960  * - write debug entry with given size and switch to next debug area
961  */
962 
963 debug_entry_t
debug_exception_common(debug_info_t * id,int level,const void * buf,int len)964 *debug_exception_common(debug_info_t * id, int level, const void *buf, int len)
965 {
966 	unsigned long flags;
967 	debug_entry_t *active;
968 
969 	if (!debug_active || !id->areas)
970 		return NULL;
971 	spin_lock_irqsave(&id->lock, flags);
972 	active = get_active_entry(id);
973 	memset(DEBUG_DATA(active), 0, id->buf_size);
974 	memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
975 	debug_finish_entry(id, active, level, 1);
976 	spin_unlock_irqrestore(&id->lock, flags);
977 
978 	return active;
979 }
980 
981 /*
982  * counts arguments in format string for sprintf view
983  */
984 
985 static inline int
debug_count_numargs(char * string)986 debug_count_numargs(char *string)
987 {
988 	int numargs=0;
989 
990 	while(*string) {
991 		if(*string++=='%')
992 			numargs++;
993 	}
994 	return(numargs);
995 }
996 
997 /*
998  * debug_sprintf_event:
999  */
1000 
1001 debug_entry_t*
debug_sprintf_event(debug_info_t * id,int level,char * string,...)1002 debug_sprintf_event(debug_info_t* id, int level,char *string,...)
1003 {
1004 	va_list   ap;
1005 	int numargs,idx;
1006 	unsigned long flags;
1007 	debug_sprintf_entry_t *curr_event;
1008 	debug_entry_t *active;
1009 
1010 	if((!id) || (level > id->level))
1011 		return NULL;
1012 	if (!debug_active || !id->areas)
1013 		return NULL;
1014 	numargs=debug_count_numargs(string);
1015 
1016 	spin_lock_irqsave(&id->lock, flags);
1017 	active = get_active_entry(id);
1018 	curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active);
1019 	va_start(ap,string);
1020 	curr_event->string=string;
1021 	for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
1022 		curr_event->args[idx]=va_arg(ap,long);
1023 	va_end(ap);
1024 	debug_finish_entry(id, active, level, 0);
1025 	spin_unlock_irqrestore(&id->lock, flags);
1026 
1027 	return active;
1028 }
1029 
1030 /*
1031  * debug_sprintf_exception:
1032  */
1033 
1034 debug_entry_t*
debug_sprintf_exception(debug_info_t * id,int level,char * string,...)1035 debug_sprintf_exception(debug_info_t* id, int level,char *string,...)
1036 {
1037 	va_list   ap;
1038 	int numargs,idx;
1039 	unsigned long flags;
1040 	debug_sprintf_entry_t *curr_event;
1041 	debug_entry_t *active;
1042 
1043 	if((!id) || (level > id->level))
1044 		return NULL;
1045 	if (!debug_active || !id->areas)
1046 		return NULL;
1047 
1048 	numargs=debug_count_numargs(string);
1049 
1050 	spin_lock_irqsave(&id->lock, flags);
1051 	active = get_active_entry(id);
1052 	curr_event=(debug_sprintf_entry_t *)DEBUG_DATA(active);
1053 	va_start(ap,string);
1054 	curr_event->string=string;
1055 	for(idx=0;idx<min(numargs,(int)(id->buf_size / sizeof(long))-1);idx++)
1056 		curr_event->args[idx]=va_arg(ap,long);
1057 	va_end(ap);
1058 	debug_finish_entry(id, active, level, 1);
1059 	spin_unlock_irqrestore(&id->lock, flags);
1060 
1061 	return active;
1062 }
1063 
1064 /*
1065  * debug_init:
1066  * - is called exactly once to initialize the debug feature
1067  */
1068 
1069 static int
debug_init(void)1070 __init debug_init(void)
1071 {
1072 	int rc = 0;
1073 
1074 	s390dbf_sysctl_header = register_sysctl_table(s390dbf_dir_table);
1075 	mutex_lock(&debug_mutex);
1076 	debug_debugfs_root_entry = debugfs_create_dir(DEBUG_DIR_ROOT,NULL);
1077 	initialized = 1;
1078 	mutex_unlock(&debug_mutex);
1079 
1080 	return rc;
1081 }
1082 
1083 /*
1084  * debug_register_view:
1085  */
1086 
1087 int
debug_register_view(debug_info_t * id,struct debug_view * view)1088 debug_register_view(debug_info_t * id, struct debug_view *view)
1089 {
1090 	int rc = 0;
1091 	int i;
1092 	unsigned long flags;
1093 	mode_t mode;
1094 	struct dentry *pde;
1095 
1096 	if (!id)
1097 		goto out;
1098 	mode = (id->mode | S_IFREG) & ~S_IXUGO;
1099 	if (!(view->prolog_proc || view->format_proc || view->header_proc))
1100 		mode &= ~(S_IRUSR | S_IRGRP | S_IROTH);
1101 	if (!view->input_proc)
1102 		mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);
1103 	pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry,
1104 				id , &debug_file_ops);
1105 	if (!pde){
1106 		pr_err("Registering view %s/%s failed due to out of "
1107 		       "memory\n", id->name,view->name);
1108 		rc = -1;
1109 		goto out;
1110 	}
1111 	spin_lock_irqsave(&id->lock, flags);
1112 	for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1113 		if (!id->views[i])
1114 			break;
1115 	}
1116 	if (i == DEBUG_MAX_VIEWS) {
1117 		pr_err("Registering view %s/%s would exceed the maximum "
1118 		       "number of views %i\n", id->name, view->name, i);
1119 		debugfs_remove(pde);
1120 		rc = -1;
1121 	} else {
1122 		id->views[i] = view;
1123 		id->debugfs_entries[i] = pde;
1124 	}
1125 	spin_unlock_irqrestore(&id->lock, flags);
1126 out:
1127 	return rc;
1128 }
1129 
1130 /*
1131  * debug_unregister_view:
1132  */
1133 
1134 int
debug_unregister_view(debug_info_t * id,struct debug_view * view)1135 debug_unregister_view(debug_info_t * id, struct debug_view *view)
1136 {
1137 	int rc = 0;
1138 	int i;
1139 	unsigned long flags;
1140 
1141 	if (!id)
1142 		goto out;
1143 	spin_lock_irqsave(&id->lock, flags);
1144 	for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
1145 		if (id->views[i] == view)
1146 			break;
1147 	}
1148 	if (i == DEBUG_MAX_VIEWS)
1149 		rc = -1;
1150 	else {
1151 		debugfs_remove(id->debugfs_entries[i]);
1152 		id->views[i] = NULL;
1153 	}
1154 	spin_unlock_irqrestore(&id->lock, flags);
1155 out:
1156 	return rc;
1157 }
1158 
1159 static inline char *
debug_get_user_string(const char __user * user_buf,size_t user_len)1160 debug_get_user_string(const char __user *user_buf, size_t user_len)
1161 {
1162 	char* buffer;
1163 
1164 	buffer = kmalloc(user_len + 1, GFP_KERNEL);
1165 	if (!buffer)
1166 		return ERR_PTR(-ENOMEM);
1167 	if (copy_from_user(buffer, user_buf, user_len) != 0) {
1168 		kfree(buffer);
1169 		return ERR_PTR(-EFAULT);
1170 	}
1171 	/* got the string, now strip linefeed. */
1172 	if (buffer[user_len - 1] == '\n')
1173 		buffer[user_len - 1] = 0;
1174 	else
1175 		buffer[user_len] = 0;
1176         return buffer;
1177 }
1178 
1179 static inline int
debug_get_uint(char * buf)1180 debug_get_uint(char *buf)
1181 {
1182 	int rc;
1183 
1184 	buf = skip_spaces(buf);
1185 	rc = simple_strtoul(buf, &buf, 10);
1186 	if(*buf){
1187 		rc = -EINVAL;
1188 	}
1189 	return rc;
1190 }
1191 
1192 /*
1193  * functions for debug-views
1194  ***********************************
1195 */
1196 
1197 /*
1198  * prints out actual debug level
1199  */
1200 
1201 static int
debug_prolog_pages_fn(debug_info_t * id,struct debug_view * view,char * out_buf)1202 debug_prolog_pages_fn(debug_info_t * id,
1203 				 struct debug_view *view, char *out_buf)
1204 {
1205 	return sprintf(out_buf, "%i\n", id->pages_per_area);
1206 }
1207 
1208 /*
1209  * reads new size (number of pages per debug area)
1210  */
1211 
1212 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)1213 debug_input_pages_fn(debug_info_t * id, struct debug_view *view,
1214 			struct file *file, const char __user *user_buf,
1215 			size_t user_len, loff_t * offset)
1216 {
1217 	char *str;
1218 	int rc,new_pages;
1219 
1220 	if (user_len > 0x10000)
1221                 user_len = 0x10000;
1222 	if (*offset != 0){
1223 		rc = -EPIPE;
1224 		goto out;
1225 	}
1226 	str = debug_get_user_string(user_buf,user_len);
1227 	if(IS_ERR(str)){
1228 		rc = PTR_ERR(str);
1229 		goto out;
1230 	}
1231 	new_pages = debug_get_uint(str);
1232 	if(new_pages < 0){
1233 		rc = -EINVAL;
1234 		goto free_str;
1235 	}
1236 	rc = debug_set_size(id,id->nr_areas, new_pages);
1237 	if(rc != 0){
1238 		rc = -EINVAL;
1239 		goto free_str;
1240 	}
1241 	rc = user_len;
1242 free_str:
1243 	kfree(str);
1244 out:
1245 	*offset += user_len;
1246 	return rc;		/* number of input characters */
1247 }
1248 
1249 /*
1250  * prints out actual debug level
1251  */
1252 
1253 static int
debug_prolog_level_fn(debug_info_t * id,struct debug_view * view,char * out_buf)1254 debug_prolog_level_fn(debug_info_t * id, struct debug_view *view, char *out_buf)
1255 {
1256 	int rc = 0;
1257 
1258 	if(id->level == DEBUG_OFF_LEVEL) {
1259 		rc = sprintf(out_buf,"-\n");
1260 	}
1261 	else {
1262 		rc = sprintf(out_buf, "%i\n", id->level);
1263 	}
1264 	return rc;
1265 }
1266 
1267 /*
1268  * reads new debug level
1269  */
1270 
1271 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)1272 debug_input_level_fn(debug_info_t * id, struct debug_view *view,
1273 			struct file *file, const char __user *user_buf,
1274 			size_t user_len, loff_t * offset)
1275 {
1276 	char *str;
1277 	int rc,new_level;
1278 
1279 	if (user_len > 0x10000)
1280                 user_len = 0x10000;
1281 	if (*offset != 0){
1282 		rc = -EPIPE;
1283 		goto out;
1284 	}
1285 	str = debug_get_user_string(user_buf,user_len);
1286 	if(IS_ERR(str)){
1287 		rc = PTR_ERR(str);
1288 		goto out;
1289 	}
1290 	if(str[0] == '-'){
1291 		debug_set_level(id, DEBUG_OFF_LEVEL);
1292 		rc = user_len;
1293 		goto free_str;
1294 	} else {
1295 		new_level = debug_get_uint(str);
1296 	}
1297 	if(new_level < 0) {
1298 		pr_warning("%s is not a valid level for a debug "
1299 			   "feature\n", str);
1300 		rc = -EINVAL;
1301 	} else {
1302 		debug_set_level(id, new_level);
1303 		rc = user_len;
1304 	}
1305 free_str:
1306 	kfree(str);
1307 out:
1308 	*offset += user_len;
1309 	return rc;		/* number of input characters */
1310 }
1311 
1312 
1313 /*
1314  * flushes debug areas
1315  */
1316 
debug_flush(debug_info_t * id,int area)1317 static void debug_flush(debug_info_t* id, int area)
1318 {
1319         unsigned long flags;
1320         int i,j;
1321 
1322         if(!id || !id->areas)
1323                 return;
1324         spin_lock_irqsave(&id->lock,flags);
1325         if(area == DEBUG_FLUSH_ALL){
1326                 id->active_area = 0;
1327                 memset(id->active_entries, 0, id->nr_areas * sizeof(int));
1328                 for (i = 0; i < id->nr_areas; i++) {
1329 			id->active_pages[i] = 0;
1330 			for(j = 0; j < id->pages_per_area; j++) {
1331                         	memset(id->areas[i][j], 0, PAGE_SIZE);
1332 			}
1333 		}
1334         } else if(area >= 0 && area < id->nr_areas) {
1335                 id->active_entries[area] = 0;
1336 		id->active_pages[area] = 0;
1337 		for(i = 0; i < id->pages_per_area; i++) {
1338                 	memset(id->areas[area][i],0,PAGE_SIZE);
1339 		}
1340         }
1341         spin_unlock_irqrestore(&id->lock,flags);
1342 }
1343 
1344 /*
1345  * view function: flushes debug areas
1346  */
1347 
1348 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)1349 debug_input_flush_fn(debug_info_t * id, struct debug_view *view,
1350 			struct file *file, const char __user *user_buf,
1351 			size_t user_len, loff_t * offset)
1352 {
1353         char input_buf[1];
1354         int rc = user_len;
1355 
1356 	if (user_len > 0x10000)
1357                 user_len = 0x10000;
1358         if (*offset != 0){
1359 		rc = -EPIPE;
1360                 goto out;
1361 	}
1362         if (copy_from_user(input_buf, user_buf, 1)){
1363                 rc = -EFAULT;
1364                 goto out;
1365         }
1366         if(input_buf[0] == '-') {
1367                 debug_flush(id, DEBUG_FLUSH_ALL);
1368                 goto out;
1369         }
1370         if (isdigit(input_buf[0])) {
1371                 int area = ((int) input_buf[0] - (int) '0');
1372                 debug_flush(id, area);
1373                 goto out;
1374         }
1375 
1376 	pr_info("Flushing debug data failed because %c is not a valid "
1377 		 "area\n", input_buf[0]);
1378 
1379 out:
1380         *offset += user_len;
1381         return rc;              /* number of input characters */
1382 }
1383 
1384 /*
1385  * prints debug header in raw format
1386  */
1387 
1388 static int
debug_raw_header_fn(debug_info_t * id,struct debug_view * view,int area,debug_entry_t * entry,char * out_buf)1389 debug_raw_header_fn(debug_info_t * id, struct debug_view *view,
1390 			int area, debug_entry_t * entry, char *out_buf)
1391 {
1392         int rc;
1393 
1394 	rc = sizeof(debug_entry_t);
1395 	memcpy(out_buf,entry,sizeof(debug_entry_t));
1396         return rc;
1397 }
1398 
1399 /*
1400  * prints debug data in raw format
1401  */
1402 
1403 static int
debug_raw_format_fn(debug_info_t * id,struct debug_view * view,char * out_buf,const char * in_buf)1404 debug_raw_format_fn(debug_info_t * id, struct debug_view *view,
1405 			       char *out_buf, const char *in_buf)
1406 {
1407 	int rc;
1408 
1409 	rc = id->buf_size;
1410 	memcpy(out_buf, in_buf, id->buf_size);
1411 	return rc;
1412 }
1413 
1414 /*
1415  * prints debug data in hex/ascii format
1416  */
1417 
1418 static int
debug_hex_ascii_format_fn(debug_info_t * id,struct debug_view * view,char * out_buf,const char * in_buf)1419 debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
1420 	    		  char *out_buf, const char *in_buf)
1421 {
1422 	int i, rc = 0;
1423 
1424 	for (i = 0; i < id->buf_size; i++) {
1425                 rc += sprintf(out_buf + rc, "%02x ",
1426                               ((unsigned char *) in_buf)[i]);
1427         }
1428 	rc += sprintf(out_buf + rc, "| ");
1429 	for (i = 0; i < id->buf_size; i++) {
1430 		unsigned char c = in_buf[i];
1431 		if (!isprint(c))
1432 			rc += sprintf(out_buf + rc, ".");
1433 		else
1434 			rc += sprintf(out_buf + rc, "%c", c);
1435 	}
1436 	rc += sprintf(out_buf + rc, "\n");
1437 	return rc;
1438 }
1439 
1440 /*
1441  * prints header for debug entry
1442  */
1443 
1444 int
debug_dflt_header_fn(debug_info_t * id,struct debug_view * view,int area,debug_entry_t * entry,char * out_buf)1445 debug_dflt_header_fn(debug_info_t * id, struct debug_view *view,
1446 			 int area, debug_entry_t * entry, char *out_buf)
1447 {
1448 	struct timespec time_spec;
1449 	char *except_str;
1450 	unsigned long caller;
1451 	int rc = 0;
1452 	unsigned int level;
1453 
1454 	level = entry->id.fields.level;
1455 	stck_to_timespec(entry->id.stck, &time_spec);
1456 
1457 	if (entry->id.fields.exception)
1458 		except_str = "*";
1459 	else
1460 		except_str = "-";
1461 	caller = ((unsigned long) entry->caller) & PSW_ADDR_INSN;
1462 	rc += sprintf(out_buf, "%02i %011lu:%06lu %1u %1s %02i %p  ",
1463 		      area, time_spec.tv_sec, time_spec.tv_nsec / 1000, level,
1464 		      except_str, entry->id.fields.cpuid, (void *) caller);
1465 	return rc;
1466 }
1467 
1468 /*
1469  * prints debug data sprintf-formated:
1470  * debug_sprinf_event/exception calls must be used together with this view
1471  */
1472 
1473 #define DEBUG_SPRINTF_MAX_ARGS 10
1474 
1475 static int
debug_sprintf_format_fn(debug_info_t * id,struct debug_view * view,char * out_buf,debug_sprintf_entry_t * curr_event)1476 debug_sprintf_format_fn(debug_info_t * id, struct debug_view *view,
1477                         char *out_buf, debug_sprintf_entry_t *curr_event)
1478 {
1479 	int num_longs, num_used_args = 0,i, rc = 0;
1480 	int index[DEBUG_SPRINTF_MAX_ARGS];
1481 
1482 	/* count of longs fit into one entry */
1483 	num_longs = id->buf_size /  sizeof(long);
1484 
1485 	if(num_longs < 1)
1486 		goto out; /* bufsize of entry too small */
1487 	if(num_longs == 1) {
1488 		/* no args, we use only the string */
1489 		strcpy(out_buf, curr_event->string);
1490 		rc = strlen(curr_event->string);
1491 		goto out;
1492 	}
1493 
1494 	/* number of arguments used for sprintf (without the format string) */
1495 	num_used_args   = min(DEBUG_SPRINTF_MAX_ARGS, (num_longs - 1));
1496 
1497 	memset(index,0, DEBUG_SPRINTF_MAX_ARGS * sizeof(int));
1498 
1499 	for(i = 0; i < num_used_args; i++)
1500 		index[i] = i;
1501 
1502 	rc =  sprintf(out_buf, curr_event->string, curr_event->args[index[0]],
1503 		curr_event->args[index[1]], curr_event->args[index[2]],
1504 		curr_event->args[index[3]], curr_event->args[index[4]],
1505 		curr_event->args[index[5]], curr_event->args[index[6]],
1506 		curr_event->args[index[7]], curr_event->args[index[8]],
1507 		curr_event->args[index[9]]);
1508 
1509 out:
1510 
1511 	return rc;
1512 }
1513 
1514 /*
1515  * clean up module
1516  */
debug_exit(void)1517 static void __exit debug_exit(void)
1518 {
1519 	debugfs_remove(debug_debugfs_root_entry);
1520 	unregister_sysctl_table(s390dbf_sysctl_header);
1521 	return;
1522 }
1523 
1524 /*
1525  * module definitions
1526  */
1527 postcore_initcall(debug_init);
1528 module_exit(debug_exit);
1529 MODULE_LICENSE("GPL");
1530 
1531 EXPORT_SYMBOL(debug_register);
1532 EXPORT_SYMBOL(debug_unregister);
1533 EXPORT_SYMBOL(debug_set_level);
1534 EXPORT_SYMBOL(debug_stop_all);
1535 EXPORT_SYMBOL(debug_register_view);
1536 EXPORT_SYMBOL(debug_unregister_view);
1537 EXPORT_SYMBOL(debug_event_common);
1538 EXPORT_SYMBOL(debug_exception_common);
1539 EXPORT_SYMBOL(debug_hex_ascii_view);
1540 EXPORT_SYMBOL(debug_raw_view);
1541 EXPORT_SYMBOL(debug_dflt_header_fn);
1542 EXPORT_SYMBOL(debug_sprintf_view);
1543 EXPORT_SYMBOL(debug_sprintf_exception);
1544 EXPORT_SYMBOL(debug_sprintf_event);
1545