xref: /linux/fs/reiserfs/item_ops.c (revision 3bdab16c55f57a24245c97d707241dd9b48d1a91)
1 /*
2  * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3  */
4 
5 #include <linux/time.h>
6 #include "reiserfs.h"
7 
8 /*
9  * this contains item handlers for old item types: sd, direct,
10  * indirect, directory
11  */
12 
13 /*
14  * and where are the comments? how about saying where we can find an
15  * explanation of each item handler method? -Hans
16  */
17 
18 /* stat data functions */
19 static int sd_bytes_number(struct item_head *ih, int block_size)
20 {
21 	return 0;
22 }
23 
24 static void sd_decrement_key(struct cpu_key *key)
25 {
26 	key->on_disk_key.k_objectid--;
27 	set_cpu_key_k_type(key, TYPE_ANY);
28 	set_cpu_key_k_offset(key, (loff_t)(~0ULL >> 1));
29 }
30 
31 static int sd_is_left_mergeable(struct reiserfs_key *key, unsigned long bsize)
32 {
33 	return 0;
34 }
35 
36 static void sd_print_item(struct item_head *ih, char *item)
37 {
38 	printk("\tmode | size | nlinks | first direct | mtime\n");
39 	if (stat_data_v1(ih)) {
40 		struct stat_data_v1 *sd = (struct stat_data_v1 *)item;
41 
42 		printk("\t0%-6o | %6u | %2u | %d | %u\n", sd_v1_mode(sd),
43 		       sd_v1_size(sd), sd_v1_nlink(sd),
44 		       sd_v1_first_direct_byte(sd),
45 		       sd_v1_mtime(sd));
46 	} else {
47 		struct stat_data *sd = (struct stat_data *)item;
48 
49 		printk("\t0%-6o | %6llu | %2u | %d | %u\n", sd_v2_mode(sd),
50 		       (unsigned long long)sd_v2_size(sd), sd_v2_nlink(sd),
51 		       sd_v2_rdev(sd), sd_v2_mtime(sd));
52 	}
53 }
54 
55 static void sd_check_item(struct item_head *ih, char *item)
56 {
57 	/* unused */
58 }
59 
60 static int sd_create_vi(struct virtual_node *vn,
61 			struct virtual_item *vi,
62 			int is_affected, int insert_size)
63 {
64 	vi->vi_index = TYPE_STAT_DATA;
65 	return 0;
66 }
67 
68 static int sd_check_left(struct virtual_item *vi, int free,
69 			 int start_skip, int end_skip)
70 {
71 	BUG_ON(start_skip || end_skip);
72 	return -1;
73 }
74 
75 static int sd_check_right(struct virtual_item *vi, int free)
76 {
77 	return -1;
78 }
79 
80 static int sd_part_size(struct virtual_item *vi, int first, int count)
81 {
82 	BUG_ON(count);
83 	return 0;
84 }
85 
86 static int sd_unit_num(struct virtual_item *vi)
87 {
88 	return vi->vi_item_len - IH_SIZE;
89 }
90 
91 static void sd_print_vi(struct virtual_item *vi)
92 {
93 	reiserfs_warning(NULL, "reiserfs-16100",
94 			 "STATDATA, index %d, type 0x%x, %h",
95 			 vi->vi_index, vi->vi_type, vi->vi_ih);
96 }
97 
98 static struct item_operations stat_data_ops = {
99 	.bytes_number = sd_bytes_number,
100 	.decrement_key = sd_decrement_key,
101 	.is_left_mergeable = sd_is_left_mergeable,
102 	.print_item = sd_print_item,
103 	.check_item = sd_check_item,
104 
105 	.create_vi = sd_create_vi,
106 	.check_left = sd_check_left,
107 	.check_right = sd_check_right,
108 	.part_size = sd_part_size,
109 	.unit_num = sd_unit_num,
110 	.print_vi = sd_print_vi
111 };
112 
113 /* direct item functions */
114 static int direct_bytes_number(struct item_head *ih, int block_size)
115 {
116 	return ih_item_len(ih);
117 }
118 
119 /* FIXME: this should probably switch to indirect as well */
120 static void direct_decrement_key(struct cpu_key *key)
121 {
122 	cpu_key_k_offset_dec(key);
123 	if (cpu_key_k_offset(key) == 0)
124 		set_cpu_key_k_type(key, TYPE_STAT_DATA);
125 }
126 
127 static int direct_is_left_mergeable(struct reiserfs_key *key,
128 				    unsigned long bsize)
129 {
130 	int version = le_key_version(key);
131 	return ((le_key_k_offset(version, key) & (bsize - 1)) != 1);
132 }
133 
134 static void direct_print_item(struct item_head *ih, char *item)
135 {
136 	int j = 0;
137 
138 /*    return; */
139 	printk("\"");
140 	while (j < ih_item_len(ih))
141 		printk("%c", item[j++]);
142 	printk("\"\n");
143 }
144 
145 static void direct_check_item(struct item_head *ih, char *item)
146 {
147 	/* unused */
148 }
149 
150 static int direct_create_vi(struct virtual_node *vn,
151 			    struct virtual_item *vi,
152 			    int is_affected, int insert_size)
153 {
154 	vi->vi_index = TYPE_DIRECT;
155 	return 0;
156 }
157 
158 static int direct_check_left(struct virtual_item *vi, int free,
159 			     int start_skip, int end_skip)
160 {
161 	int bytes;
162 
163 	bytes = free - free % 8;
164 	return bytes ? : -1;
165 }
166 
167 static int direct_check_right(struct virtual_item *vi, int free)
168 {
169 	return direct_check_left(vi, free, 0, 0);
170 }
171 
172 static int direct_part_size(struct virtual_item *vi, int first, int count)
173 {
174 	return count;
175 }
176 
177 static int direct_unit_num(struct virtual_item *vi)
178 {
179 	return vi->vi_item_len - IH_SIZE;
180 }
181 
182 static void direct_print_vi(struct virtual_item *vi)
183 {
184 	reiserfs_warning(NULL, "reiserfs-16101",
185 			 "DIRECT, index %d, type 0x%x, %h",
186 			 vi->vi_index, vi->vi_type, vi->vi_ih);
187 }
188 
189 static struct item_operations direct_ops = {
190 	.bytes_number = direct_bytes_number,
191 	.decrement_key = direct_decrement_key,
192 	.is_left_mergeable = direct_is_left_mergeable,
193 	.print_item = direct_print_item,
194 	.check_item = direct_check_item,
195 
196 	.create_vi = direct_create_vi,
197 	.check_left = direct_check_left,
198 	.check_right = direct_check_right,
199 	.part_size = direct_part_size,
200 	.unit_num = direct_unit_num,
201 	.print_vi = direct_print_vi
202 };
203 
204 /* indirect item functions */
205 static int indirect_bytes_number(struct item_head *ih, int block_size)
206 {
207 	return ih_item_len(ih) / UNFM_P_SIZE * block_size;
208 }
209 
210 /* decrease offset, if it becomes 0, change type to stat data */
211 static void indirect_decrement_key(struct cpu_key *key)
212 {
213 	cpu_key_k_offset_dec(key);
214 	if (cpu_key_k_offset(key) == 0)
215 		set_cpu_key_k_type(key, TYPE_STAT_DATA);
216 }
217 
218 /* if it is not first item of the body, then it is mergeable */
219 static int indirect_is_left_mergeable(struct reiserfs_key *key,
220 				      unsigned long bsize)
221 {
222 	int version = le_key_version(key);
223 	return (le_key_k_offset(version, key) != 1);
224 }
225 
226 /* printing of indirect item */
227 static void start_new_sequence(__u32 * start, int *len, __u32 new)
228 {
229 	*start = new;
230 	*len = 1;
231 }
232 
233 static int sequence_finished(__u32 start, int *len, __u32 new)
234 {
235 	if (start == INT_MAX)
236 		return 1;
237 
238 	if (start == 0 && new == 0) {
239 		(*len)++;
240 		return 0;
241 	}
242 	if (start != 0 && (start + *len) == new) {
243 		(*len)++;
244 		return 0;
245 	}
246 	return 1;
247 }
248 
249 static void print_sequence(__u32 start, int len)
250 {
251 	if (start == INT_MAX)
252 		return;
253 
254 	if (len == 1)
255 		printk(" %d", start);
256 	else
257 		printk(" %d(%d)", start, len);
258 }
259 
260 static void indirect_print_item(struct item_head *ih, char *item)
261 {
262 	int j;
263 	__le32 *unp;
264 	__u32 prev = INT_MAX;
265 	int num = 0;
266 
267 	unp = (__le32 *) item;
268 
269 	if (ih_item_len(ih) % UNFM_P_SIZE)
270 		reiserfs_warning(NULL, "reiserfs-16102", "invalid item len");
271 
272 	printk("%d pointers\n[ ", (int)I_UNFM_NUM(ih));
273 	for (j = 0; j < I_UNFM_NUM(ih); j++) {
274 		if (sequence_finished(prev, &num, get_block_num(unp, j))) {
275 			print_sequence(prev, num);
276 			start_new_sequence(&prev, &num, get_block_num(unp, j));
277 		}
278 	}
279 	print_sequence(prev, num);
280 	printk("]\n");
281 }
282 
283 static void indirect_check_item(struct item_head *ih, char *item)
284 {
285 	/* unused */
286 }
287 
288 static int indirect_create_vi(struct virtual_node *vn,
289 			      struct virtual_item *vi,
290 			      int is_affected, int insert_size)
291 {
292 	vi->vi_index = TYPE_INDIRECT;
293 	return 0;
294 }
295 
296 static int indirect_check_left(struct virtual_item *vi, int free,
297 			       int start_skip, int end_skip)
298 {
299 	int bytes;
300 
301 	bytes = free - free % UNFM_P_SIZE;
302 	return bytes ? : -1;
303 }
304 
305 static int indirect_check_right(struct virtual_item *vi, int free)
306 {
307 	return indirect_check_left(vi, free, 0, 0);
308 }
309 
310 /*
311  * return size in bytes of 'units' units. If first == 0 - calculate
312  * from the head (left), otherwise - from tail (right)
313  */
314 static int indirect_part_size(struct virtual_item *vi, int first, int units)
315 {
316 	/* unit of indirect item is byte (yet) */
317 	return units;
318 }
319 
320 static int indirect_unit_num(struct virtual_item *vi)
321 {
322 	/* unit of indirect item is byte (yet) */
323 	return vi->vi_item_len - IH_SIZE;
324 }
325 
326 static void indirect_print_vi(struct virtual_item *vi)
327 {
328 	reiserfs_warning(NULL, "reiserfs-16103",
329 			 "INDIRECT, index %d, type 0x%x, %h",
330 			 vi->vi_index, vi->vi_type, vi->vi_ih);
331 }
332 
333 static struct item_operations indirect_ops = {
334 	.bytes_number = indirect_bytes_number,
335 	.decrement_key = indirect_decrement_key,
336 	.is_left_mergeable = indirect_is_left_mergeable,
337 	.print_item = indirect_print_item,
338 	.check_item = indirect_check_item,
339 
340 	.create_vi = indirect_create_vi,
341 	.check_left = indirect_check_left,
342 	.check_right = indirect_check_right,
343 	.part_size = indirect_part_size,
344 	.unit_num = indirect_unit_num,
345 	.print_vi = indirect_print_vi
346 };
347 
348 /* direntry functions */
349 static int direntry_bytes_number(struct item_head *ih, int block_size)
350 {
351 	reiserfs_warning(NULL, "vs-16090",
352 			 "bytes number is asked for direntry");
353 	return 0;
354 }
355 
356 static void direntry_decrement_key(struct cpu_key *key)
357 {
358 	cpu_key_k_offset_dec(key);
359 	if (cpu_key_k_offset(key) == 0)
360 		set_cpu_key_k_type(key, TYPE_STAT_DATA);
361 }
362 
363 static int direntry_is_left_mergeable(struct reiserfs_key *key,
364 				      unsigned long bsize)
365 {
366 	if (le32_to_cpu(key->u.k_offset_v1.k_offset) == DOT_OFFSET)
367 		return 0;
368 	return 1;
369 
370 }
371 
372 static void direntry_print_item(struct item_head *ih, char *item)
373 {
374 	int i;
375 	int namelen;
376 	struct reiserfs_de_head *deh;
377 	char *name;
378 	static char namebuf[80];
379 
380 	printk("\n # %-15s%-30s%-15s%-15s%-15s\n", "Name",
381 	       "Key of pointed object", "Hash", "Gen number", "Status");
382 
383 	deh = (struct reiserfs_de_head *)item;
384 
385 	for (i = 0; i < ih_entry_count(ih); i++, deh++) {
386 		namelen =
387 		    (i ? (deh_location(deh - 1)) : ih_item_len(ih)) -
388 		    deh_location(deh);
389 		name = item + deh_location(deh);
390 		if (name[namelen - 1] == 0)
391 			namelen = strlen(name);
392 		namebuf[0] = '"';
393 		if (namelen > sizeof(namebuf) - 3) {
394 			strncpy(namebuf + 1, name, sizeof(namebuf) - 3);
395 			namebuf[sizeof(namebuf) - 2] = '"';
396 			namebuf[sizeof(namebuf) - 1] = 0;
397 		} else {
398 			memcpy(namebuf + 1, name, namelen);
399 			namebuf[namelen + 1] = '"';
400 			namebuf[namelen + 2] = 0;
401 		}
402 
403 		printk("%d:  %-15s%-15d%-15d%-15lld%-15lld(%s)\n",
404 		       i, namebuf,
405 		       deh_dir_id(deh), deh_objectid(deh),
406 		       GET_HASH_VALUE(deh_offset(deh)),
407 		       GET_GENERATION_NUMBER((deh_offset(deh))),
408 		       (de_hidden(deh)) ? "HIDDEN" : "VISIBLE");
409 	}
410 }
411 
412 static void direntry_check_item(struct item_head *ih, char *item)
413 {
414 	int i;
415 	struct reiserfs_de_head *deh;
416 
417 	/* unused */
418 	deh = (struct reiserfs_de_head *)item;
419 	for (i = 0; i < ih_entry_count(ih); i++, deh++) {
420 		;
421 	}
422 }
423 
424 #define DIRENTRY_VI_FIRST_DIRENTRY_ITEM 1
425 
426 /*
427  * function returns old entry number in directory item in real node
428  * using new entry number in virtual item in virtual node
429  */
430 static inline int old_entry_num(int is_affected, int virtual_entry_num,
431 				int pos_in_item, int mode)
432 {
433 	if (mode == M_INSERT || mode == M_DELETE)
434 		return virtual_entry_num;
435 
436 	if (!is_affected)
437 		/* cut or paste is applied to another item */
438 		return virtual_entry_num;
439 
440 	if (virtual_entry_num < pos_in_item)
441 		return virtual_entry_num;
442 
443 	if (mode == M_CUT)
444 		return virtual_entry_num + 1;
445 
446 	RFALSE(mode != M_PASTE || virtual_entry_num == 0,
447 	       "vs-8015: old_entry_num: mode must be M_PASTE (mode = \'%c\'",
448 	       mode);
449 
450 	return virtual_entry_num - 1;
451 }
452 
453 /*
454  * Create an array of sizes of directory entries for virtual
455  * item. Return space used by an item. FIXME: no control over
456  * consuming of space used by this item handler
457  */
458 static int direntry_create_vi(struct virtual_node *vn,
459 			      struct virtual_item *vi,
460 			      int is_affected, int insert_size)
461 {
462 	struct direntry_uarea *dir_u = vi->vi_uarea;
463 	int i, j;
464 	int size = sizeof(struct direntry_uarea);
465 	struct reiserfs_de_head *deh;
466 
467 	vi->vi_index = TYPE_DIRENTRY;
468 
469 	BUG_ON(!(vi->vi_ih) || !vi->vi_item);
470 
471 	dir_u->flags = 0;
472 	if (le_ih_k_offset(vi->vi_ih) == DOT_OFFSET)
473 		dir_u->flags |= DIRENTRY_VI_FIRST_DIRENTRY_ITEM;
474 
475 	deh = (struct reiserfs_de_head *)(vi->vi_item);
476 
477 	/* virtual directory item have this amount of entry after */
478 	dir_u->entry_count = ih_entry_count(vi->vi_ih) +
479 	    ((is_affected) ? ((vn->vn_mode == M_CUT) ? -1 :
480 			      (vn->vn_mode == M_PASTE ? 1 : 0)) : 0);
481 
482 	for (i = 0; i < dir_u->entry_count; i++) {
483 		j = old_entry_num(is_affected, i, vn->vn_pos_in_item,
484 				  vn->vn_mode);
485 		dir_u->entry_sizes[i] =
486 		    (j ? deh_location(&deh[j - 1]) : ih_item_len(vi->vi_ih)) -
487 		    deh_location(&deh[j]) + DEH_SIZE;
488 	}
489 
490 	size += (dir_u->entry_count * sizeof(short));
491 
492 	/* set size of pasted entry */
493 	if (is_affected && vn->vn_mode == M_PASTE)
494 		dir_u->entry_sizes[vn->vn_pos_in_item] = insert_size;
495 
496 #ifdef CONFIG_REISERFS_CHECK
497 	/* compare total size of entries with item length */
498 	{
499 		int k, l;
500 
501 		l = 0;
502 		for (k = 0; k < dir_u->entry_count; k++)
503 			l += dir_u->entry_sizes[k];
504 
505 		if (l + IH_SIZE != vi->vi_item_len +
506 		    ((is_affected
507 		      && (vn->vn_mode == M_PASTE
508 			  || vn->vn_mode == M_CUT)) ? insert_size : 0)) {
509 			reiserfs_panic(NULL, "vs-8025", "(mode==%c, "
510 				       "insert_size==%d), invalid length of "
511 				       "directory item",
512 				       vn->vn_mode, insert_size);
513 		}
514 	}
515 #endif
516 
517 	return size;
518 
519 }
520 
521 /*
522  * return number of entries which may fit into specified amount of
523  * free space, or -1 if free space is not enough even for 1 entry
524  */
525 static int direntry_check_left(struct virtual_item *vi, int free,
526 			       int start_skip, int end_skip)
527 {
528 	int i;
529 	int entries = 0;
530 	struct direntry_uarea *dir_u = vi->vi_uarea;
531 
532 	for (i = start_skip; i < dir_u->entry_count - end_skip; i++) {
533 		/* i-th entry doesn't fit into the remaining free space */
534 		if (dir_u->entry_sizes[i] > free)
535 			break;
536 
537 		free -= dir_u->entry_sizes[i];
538 		entries++;
539 	}
540 
541 	if (entries == dir_u->entry_count) {
542 		reiserfs_panic(NULL, "item_ops-1",
543 			       "free space %d, entry_count %d", free,
544 			       dir_u->entry_count);
545 	}
546 
547 	/* "." and ".." can not be separated from each other */
548 	if (start_skip == 0 && (dir_u->flags & DIRENTRY_VI_FIRST_DIRENTRY_ITEM)
549 	    && entries < 2)
550 		entries = 0;
551 
552 	return entries ? : -1;
553 }
554 
555 static int direntry_check_right(struct virtual_item *vi, int free)
556 {
557 	int i;
558 	int entries = 0;
559 	struct direntry_uarea *dir_u = vi->vi_uarea;
560 
561 	for (i = dir_u->entry_count - 1; i >= 0; i--) {
562 		/* i-th entry doesn't fit into the remaining free space */
563 		if (dir_u->entry_sizes[i] > free)
564 			break;
565 
566 		free -= dir_u->entry_sizes[i];
567 		entries++;
568 	}
569 	BUG_ON(entries == dir_u->entry_count);
570 
571 	/* "." and ".." can not be separated from each other */
572 	if ((dir_u->flags & DIRENTRY_VI_FIRST_DIRENTRY_ITEM)
573 	    && entries > dir_u->entry_count - 2)
574 		entries = dir_u->entry_count - 2;
575 
576 	return entries ? : -1;
577 }
578 
579 /* sum of entry sizes between from-th and to-th entries including both edges */
580 static int direntry_part_size(struct virtual_item *vi, int first, int count)
581 {
582 	int i, retval;
583 	int from, to;
584 	struct direntry_uarea *dir_u = vi->vi_uarea;
585 
586 	retval = 0;
587 	if (first == 0)
588 		from = 0;
589 	else
590 		from = dir_u->entry_count - count;
591 	to = from + count - 1;
592 
593 	for (i = from; i <= to; i++)
594 		retval += dir_u->entry_sizes[i];
595 
596 	return retval;
597 }
598 
599 static int direntry_unit_num(struct virtual_item *vi)
600 {
601 	struct direntry_uarea *dir_u = vi->vi_uarea;
602 
603 	return dir_u->entry_count;
604 }
605 
606 static void direntry_print_vi(struct virtual_item *vi)
607 {
608 	int i;
609 	struct direntry_uarea *dir_u = vi->vi_uarea;
610 
611 	reiserfs_warning(NULL, "reiserfs-16104",
612 			 "DIRENTRY, index %d, type 0x%x, %h, flags 0x%x",
613 			 vi->vi_index, vi->vi_type, vi->vi_ih, dir_u->flags);
614 	printk("%d entries: ", dir_u->entry_count);
615 	for (i = 0; i < dir_u->entry_count; i++)
616 		printk("%d ", dir_u->entry_sizes[i]);
617 	printk("\n");
618 }
619 
620 static struct item_operations direntry_ops = {
621 	.bytes_number = direntry_bytes_number,
622 	.decrement_key = direntry_decrement_key,
623 	.is_left_mergeable = direntry_is_left_mergeable,
624 	.print_item = direntry_print_item,
625 	.check_item = direntry_check_item,
626 
627 	.create_vi = direntry_create_vi,
628 	.check_left = direntry_check_left,
629 	.check_right = direntry_check_right,
630 	.part_size = direntry_part_size,
631 	.unit_num = direntry_unit_num,
632 	.print_vi = direntry_print_vi
633 };
634 
635 /* Error catching functions to catch errors caused by incorrect item types. */
636 static int errcatch_bytes_number(struct item_head *ih, int block_size)
637 {
638 	reiserfs_warning(NULL, "green-16001",
639 			 "Invalid item type observed, run fsck ASAP");
640 	return 0;
641 }
642 
643 static void errcatch_decrement_key(struct cpu_key *key)
644 {
645 	reiserfs_warning(NULL, "green-16002",
646 			 "Invalid item type observed, run fsck ASAP");
647 }
648 
649 static int errcatch_is_left_mergeable(struct reiserfs_key *key,
650 				      unsigned long bsize)
651 {
652 	reiserfs_warning(NULL, "green-16003",
653 			 "Invalid item type observed, run fsck ASAP");
654 	return 0;
655 }
656 
657 static void errcatch_print_item(struct item_head *ih, char *item)
658 {
659 	reiserfs_warning(NULL, "green-16004",
660 			 "Invalid item type observed, run fsck ASAP");
661 }
662 
663 static void errcatch_check_item(struct item_head *ih, char *item)
664 {
665 	reiserfs_warning(NULL, "green-16005",
666 			 "Invalid item type observed, run fsck ASAP");
667 }
668 
669 static int errcatch_create_vi(struct virtual_node *vn,
670 			      struct virtual_item *vi,
671 			      int is_affected, int insert_size)
672 {
673 	reiserfs_warning(NULL, "green-16006",
674 			 "Invalid item type observed, run fsck ASAP");
675 	/*
676 	 * We might return -1 here as well, but it won't help as
677 	 * create_virtual_node() from where this operation is called
678 	 * from is of return type void.
679 	 */
680 	return 0;
681 }
682 
683 static int errcatch_check_left(struct virtual_item *vi, int free,
684 			       int start_skip, int end_skip)
685 {
686 	reiserfs_warning(NULL, "green-16007",
687 			 "Invalid item type observed, run fsck ASAP");
688 	return -1;
689 }
690 
691 static int errcatch_check_right(struct virtual_item *vi, int free)
692 {
693 	reiserfs_warning(NULL, "green-16008",
694 			 "Invalid item type observed, run fsck ASAP");
695 	return -1;
696 }
697 
698 static int errcatch_part_size(struct virtual_item *vi, int first, int count)
699 {
700 	reiserfs_warning(NULL, "green-16009",
701 			 "Invalid item type observed, run fsck ASAP");
702 	return 0;
703 }
704 
705 static int errcatch_unit_num(struct virtual_item *vi)
706 {
707 	reiserfs_warning(NULL, "green-16010",
708 			 "Invalid item type observed, run fsck ASAP");
709 	return 0;
710 }
711 
712 static void errcatch_print_vi(struct virtual_item *vi)
713 {
714 	reiserfs_warning(NULL, "green-16011",
715 			 "Invalid item type observed, run fsck ASAP");
716 }
717 
718 static struct item_operations errcatch_ops = {
719 	.bytes_number = errcatch_bytes_number,
720 	.decrement_key = errcatch_decrement_key,
721 	.is_left_mergeable = errcatch_is_left_mergeable,
722 	.print_item = errcatch_print_item,
723 	.check_item = errcatch_check_item,
724 
725 	.create_vi = errcatch_create_vi,
726 	.check_left = errcatch_check_left,
727 	.check_right = errcatch_check_right,
728 	.part_size = errcatch_part_size,
729 	.unit_num = errcatch_unit_num,
730 	.print_vi = errcatch_print_vi
731 };
732 
733 #if ! (TYPE_STAT_DATA == 0 && TYPE_INDIRECT == 1 && TYPE_DIRECT == 2 && TYPE_DIRENTRY == 3)
734 #error Item types must use disk-format assigned values.
735 #endif
736 
737 struct item_operations *item_ops[TYPE_ANY + 1] = {
738 	&stat_data_ops,
739 	&indirect_ops,
740 	&direct_ops,
741 	&direntry_ops,
742 	NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
743 	&errcatch_ops		/* This is to catch errors with invalid type (15th entry for TYPE_ANY) */
744 };
745