xref: /openbmc/linux/fs/reiserfs/lbalance.c (revision b04b4f78)
1 /*
2  * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3  */
4 
5 #include <asm/uaccess.h>
6 #include <linux/string.h>
7 #include <linux/time.h>
8 #include <linux/reiserfs_fs.h>
9 #include <linux/buffer_head.h>
10 
11 /* these are used in do_balance.c */
12 
13 /* leaf_move_items
14    leaf_shift_left
15    leaf_shift_right
16    leaf_delete_items
17    leaf_insert_into_buf
18    leaf_paste_in_buffer
19    leaf_cut_from_buffer
20    leaf_paste_entries
21    */
22 
23 /* copy copy_count entries from source directory item to dest buffer (creating new item if needed) */
24 static void leaf_copy_dir_entries(struct buffer_info *dest_bi,
25 				  struct buffer_head *source, int last_first,
26 				  int item_num, int from, int copy_count)
27 {
28 	struct buffer_head *dest = dest_bi->bi_bh;
29 	int item_num_in_dest;	/* either the number of target item,
30 				   or if we must create a new item,
31 				   the number of the item we will
32 				   create it next to */
33 	struct item_head *ih;
34 	struct reiserfs_de_head *deh;
35 	int copy_records_len;	/* length of all records in item to be copied */
36 	char *records;
37 
38 	ih = B_N_PITEM_HEAD(source, item_num);
39 
40 	RFALSE(!is_direntry_le_ih(ih), "vs-10000: item must be directory item");
41 
42 	/* length of all record to be copied and first byte of the last of them */
43 	deh = B_I_DEH(source, ih);
44 	if (copy_count) {
45 		copy_records_len = (from ? deh_location(&(deh[from - 1])) :
46 				    ih_item_len(ih)) -
47 		    deh_location(&(deh[from + copy_count - 1]));
48 		records =
49 		    source->b_data + ih_location(ih) +
50 		    deh_location(&(deh[from + copy_count - 1]));
51 	} else {
52 		copy_records_len = 0;
53 		records = NULL;
54 	}
55 
56 	/* when copy last to first, dest buffer can contain 0 items */
57 	item_num_in_dest =
58 	    (last_first ==
59 	     LAST_TO_FIRST) ? ((B_NR_ITEMS(dest)) ? 0 : -1) : (B_NR_ITEMS(dest)
60 							       - 1);
61 
62 	/* if there are no items in dest or the first/last item in dest is not item of the same directory */
63 	if ((item_num_in_dest == -1) ||
64 	    (last_first == FIRST_TO_LAST && le_ih_k_offset(ih) == DOT_OFFSET) ||
65 	    (last_first == LAST_TO_FIRST
66 	     && comp_short_le_keys /*COMP_SHORT_KEYS */ (&ih->ih_key,
67 							 B_N_PKEY(dest,
68 								  item_num_in_dest))))
69 	{
70 		/* create new item in dest */
71 		struct item_head new_ih;
72 
73 		/* form item header */
74 		memcpy(&new_ih.ih_key, &ih->ih_key, KEY_SIZE);
75 		put_ih_version(&new_ih, KEY_FORMAT_3_5);
76 		/* calculate item len */
77 		put_ih_item_len(&new_ih,
78 				DEH_SIZE * copy_count + copy_records_len);
79 		put_ih_entry_count(&new_ih, 0);
80 
81 		if (last_first == LAST_TO_FIRST) {
82 			/* form key by the following way */
83 			if (from < I_ENTRY_COUNT(ih)) {
84 				set_le_ih_k_offset(&new_ih,
85 						   deh_offset(&(deh[from])));
86 				/*memcpy (&new_ih.ih_key.k_offset, &deh[from].deh_offset, SHORT_KEY_SIZE); */
87 			} else {
88 				/* no entries will be copied to this item in this function */
89 				set_le_ih_k_offset(&new_ih, U32_MAX);
90 				/* this item is not yet valid, but we want I_IS_DIRECTORY_ITEM to return 1 for it, so we -1 */
91 			}
92 			set_le_key_k_type(KEY_FORMAT_3_5, &(new_ih.ih_key),
93 					  TYPE_DIRENTRY);
94 		}
95 
96 		/* insert item into dest buffer */
97 		leaf_insert_into_buf(dest_bi,
98 				     (last_first ==
99 				      LAST_TO_FIRST) ? 0 : B_NR_ITEMS(dest),
100 				     &new_ih, NULL, 0);
101 	} else {
102 		/* prepare space for entries */
103 		leaf_paste_in_buffer(dest_bi,
104 				     (last_first ==
105 				      FIRST_TO_LAST) ? (B_NR_ITEMS(dest) -
106 							1) : 0, MAX_US_INT,
107 				     DEH_SIZE * copy_count + copy_records_len,
108 				     records, 0);
109 	}
110 
111 	item_num_in_dest =
112 	    (last_first == FIRST_TO_LAST) ? (B_NR_ITEMS(dest) - 1) : 0;
113 
114 	leaf_paste_entries(dest_bi, item_num_in_dest,
115 			   (last_first ==
116 			    FIRST_TO_LAST) ? I_ENTRY_COUNT(B_N_PITEM_HEAD(dest,
117 									  item_num_in_dest))
118 			   : 0, copy_count, deh + from, records,
119 			   DEH_SIZE * copy_count + copy_records_len);
120 }
121 
122 /* Copy the first (if last_first == FIRST_TO_LAST) or last (last_first == LAST_TO_FIRST) item or
123    part of it or nothing (see the return 0 below) from SOURCE to the end
124    (if last_first) or beginning (!last_first) of the DEST */
125 /* returns 1 if anything was copied, else 0 */
126 static int leaf_copy_boundary_item(struct buffer_info *dest_bi,
127 				   struct buffer_head *src, int last_first,
128 				   int bytes_or_entries)
129 {
130 	struct buffer_head *dest = dest_bi->bi_bh;
131 	int dest_nr_item, src_nr_item;	/* number of items in the source and destination buffers */
132 	struct item_head *ih;
133 	struct item_head *dih;
134 
135 	dest_nr_item = B_NR_ITEMS(dest);
136 
137 	if (last_first == FIRST_TO_LAST) {
138 		/* if ( DEST is empty or first item of SOURCE and last item of DEST are the items of different objects
139 		   or of different types ) then there is no need to treat this item differently from the other items
140 		   that we copy, so we return */
141 		ih = B_N_PITEM_HEAD(src, 0);
142 		dih = B_N_PITEM_HEAD(dest, dest_nr_item - 1);
143 		if (!dest_nr_item
144 		    || (!op_is_left_mergeable(&(ih->ih_key), src->b_size)))
145 			/* there is nothing to merge */
146 			return 0;
147 
148 		RFALSE(!ih_item_len(ih),
149 		       "vs-10010: item can not have empty length");
150 
151 		if (is_direntry_le_ih(ih)) {
152 			if (bytes_or_entries == -1)
153 				/* copy all entries to dest */
154 				bytes_or_entries = ih_entry_count(ih);
155 			leaf_copy_dir_entries(dest_bi, src, FIRST_TO_LAST, 0, 0,
156 					      bytes_or_entries);
157 			return 1;
158 		}
159 
160 		/* copy part of the body of the first item of SOURCE to the end of the body of the last item of the DEST
161 		   part defined by 'bytes_or_entries'; if bytes_or_entries == -1 copy whole body; don't create new item header
162 		 */
163 		if (bytes_or_entries == -1)
164 			bytes_or_entries = ih_item_len(ih);
165 
166 #ifdef CONFIG_REISERFS_CHECK
167 		else {
168 			if (bytes_or_entries == ih_item_len(ih)
169 			    && is_indirect_le_ih(ih))
170 				if (get_ih_free_space(ih))
171 					reiserfs_panic(sb_from_bi(dest_bi),
172 						       "vs-10020",
173 						       "last unformatted node "
174 						       "must be filled "
175 						       "entirely (%h)", ih);
176 		}
177 #endif
178 
179 		/* merge first item (or its part) of src buffer with the last
180 		   item of dest buffer. Both are of the same file */
181 		leaf_paste_in_buffer(dest_bi,
182 				     dest_nr_item - 1, ih_item_len(dih),
183 				     bytes_or_entries, B_I_PITEM(src, ih), 0);
184 
185 		if (is_indirect_le_ih(dih)) {
186 			RFALSE(get_ih_free_space(dih),
187 			       "vs-10030: merge to left: last unformatted node of non-last indirect item %h must have zerto free space",
188 			       ih);
189 			if (bytes_or_entries == ih_item_len(ih))
190 				set_ih_free_space(dih, get_ih_free_space(ih));
191 		}
192 
193 		return 1;
194 	}
195 
196 	/* copy boundary item to right (last_first == LAST_TO_FIRST) */
197 
198 	/* ( DEST is empty or last item of SOURCE and first item of DEST
199 	   are the items of different object or of different types )
200 	 */
201 	src_nr_item = B_NR_ITEMS(src);
202 	ih = B_N_PITEM_HEAD(src, src_nr_item - 1);
203 	dih = B_N_PITEM_HEAD(dest, 0);
204 
205 	if (!dest_nr_item || !op_is_left_mergeable(&(dih->ih_key), src->b_size))
206 		return 0;
207 
208 	if (is_direntry_le_ih(ih)) {
209 		if (bytes_or_entries == -1)
210 			/* bytes_or_entries = entries number in last item body of SOURCE */
211 			bytes_or_entries = ih_entry_count(ih);
212 
213 		leaf_copy_dir_entries(dest_bi, src, LAST_TO_FIRST,
214 				      src_nr_item - 1,
215 				      ih_entry_count(ih) - bytes_or_entries,
216 				      bytes_or_entries);
217 		return 1;
218 	}
219 
220 	/* copy part of the body of the last item of SOURCE to the begin of the body of the first item of the DEST;
221 	   part defined by 'bytes_or_entries'; if byte_or_entriess == -1 copy whole body; change first item key of the DEST;
222 	   don't create new item header
223 	 */
224 
225 	RFALSE(is_indirect_le_ih(ih) && get_ih_free_space(ih),
226 	       "vs-10040: merge to right: last unformatted node of non-last indirect item must be filled entirely (%h)",
227 	       ih);
228 
229 	if (bytes_or_entries == -1) {
230 		/* bytes_or_entries = length of last item body of SOURCE */
231 		bytes_or_entries = ih_item_len(ih);
232 
233 		RFALSE(le_ih_k_offset(dih) !=
234 		       le_ih_k_offset(ih) + op_bytes_number(ih, src->b_size),
235 		       "vs-10050: items %h and %h do not match", ih, dih);
236 
237 		/* change first item key of the DEST */
238 		set_le_ih_k_offset(dih, le_ih_k_offset(ih));
239 
240 		/* item becomes non-mergeable */
241 		/* or mergeable if left item was */
242 		set_le_ih_k_type(dih, le_ih_k_type(ih));
243 	} else {
244 		/* merge to right only part of item */
245 		RFALSE(ih_item_len(ih) <= bytes_or_entries,
246 		       "vs-10060: no so much bytes %lu (needed %lu)",
247 		       (unsigned long)ih_item_len(ih),
248 		       (unsigned long)bytes_or_entries);
249 
250 		/* change first item key of the DEST */
251 		if (is_direct_le_ih(dih)) {
252 			RFALSE(le_ih_k_offset(dih) <=
253 			       (unsigned long)bytes_or_entries,
254 			       "vs-10070: dih %h, bytes_or_entries(%d)", dih,
255 			       bytes_or_entries);
256 			set_le_ih_k_offset(dih,
257 					   le_ih_k_offset(dih) -
258 					   bytes_or_entries);
259 		} else {
260 			RFALSE(le_ih_k_offset(dih) <=
261 			       (bytes_or_entries / UNFM_P_SIZE) * dest->b_size,
262 			       "vs-10080: dih %h, bytes_or_entries(%d)",
263 			       dih,
264 			       (bytes_or_entries / UNFM_P_SIZE) * dest->b_size);
265 			set_le_ih_k_offset(dih,
266 					   le_ih_k_offset(dih) -
267 					   ((bytes_or_entries / UNFM_P_SIZE) *
268 					    dest->b_size));
269 		}
270 	}
271 
272 	leaf_paste_in_buffer(dest_bi, 0, 0, bytes_or_entries,
273 			     B_I_PITEM(src,
274 				       ih) + ih_item_len(ih) - bytes_or_entries,
275 			     0);
276 	return 1;
277 }
278 
279 /* copy cpy_mun items from buffer src to buffer dest
280  * last_first == FIRST_TO_LAST means, that we copy cpy_num  items beginning from first-th item in src to tail of dest
281  * last_first == LAST_TO_FIRST means, that we copy cpy_num  items beginning from first-th item in src to head of dest
282  */
283 static void leaf_copy_items_entirely(struct buffer_info *dest_bi,
284 				     struct buffer_head *src, int last_first,
285 				     int first, int cpy_num)
286 {
287 	struct buffer_head *dest;
288 	int nr, free_space;
289 	int dest_before;
290 	int last_loc, last_inserted_loc, location;
291 	int i, j;
292 	struct block_head *blkh;
293 	struct item_head *ih;
294 
295 	RFALSE(last_first != LAST_TO_FIRST && last_first != FIRST_TO_LAST,
296 	       "vs-10090: bad last_first parameter %d", last_first);
297 	RFALSE(B_NR_ITEMS(src) - first < cpy_num,
298 	       "vs-10100: too few items in source %d, required %d from %d",
299 	       B_NR_ITEMS(src), cpy_num, first);
300 	RFALSE(cpy_num < 0, "vs-10110: can not copy negative amount of items");
301 	RFALSE(!dest_bi, "vs-10120: can not copy negative amount of items");
302 
303 	dest = dest_bi->bi_bh;
304 
305 	RFALSE(!dest, "vs-10130: can not copy negative amount of items");
306 
307 	if (cpy_num == 0)
308 		return;
309 
310 	blkh = B_BLK_HEAD(dest);
311 	nr = blkh_nr_item(blkh);
312 	free_space = blkh_free_space(blkh);
313 
314 	/* we will insert items before 0-th or nr-th item in dest buffer. It depends of last_first parameter */
315 	dest_before = (last_first == LAST_TO_FIRST) ? 0 : nr;
316 
317 	/* location of head of first new item */
318 	ih = B_N_PITEM_HEAD(dest, dest_before);
319 
320 	RFALSE(blkh_free_space(blkh) < cpy_num * IH_SIZE,
321 	       "vs-10140: not enough free space for headers %d (needed %d)",
322 	       B_FREE_SPACE(dest), cpy_num * IH_SIZE);
323 
324 	/* prepare space for headers */
325 	memmove(ih + cpy_num, ih, (nr - dest_before) * IH_SIZE);
326 
327 	/* copy item headers */
328 	memcpy(ih, B_N_PITEM_HEAD(src, first), cpy_num * IH_SIZE);
329 
330 	free_space -= (IH_SIZE * cpy_num);
331 	set_blkh_free_space(blkh, free_space);
332 
333 	/* location of unmovable item */
334 	j = location = (dest_before == 0) ? dest->b_size : ih_location(ih - 1);
335 	for (i = dest_before; i < nr + cpy_num; i++) {
336 		location -= ih_item_len(ih + i - dest_before);
337 		put_ih_location(ih + i - dest_before, location);
338 	}
339 
340 	/* prepare space for items */
341 	last_loc = ih_location(&(ih[nr + cpy_num - 1 - dest_before]));
342 	last_inserted_loc = ih_location(&(ih[cpy_num - 1]));
343 
344 	/* check free space */
345 	RFALSE(free_space < j - last_inserted_loc,
346 	       "vs-10150: not enough free space for items %d (needed %d)",
347 	       free_space, j - last_inserted_loc);
348 
349 	memmove(dest->b_data + last_loc,
350 		dest->b_data + last_loc + j - last_inserted_loc,
351 		last_inserted_loc - last_loc);
352 
353 	/* copy items */
354 	memcpy(dest->b_data + last_inserted_loc,
355 	       B_N_PITEM(src, (first + cpy_num - 1)), j - last_inserted_loc);
356 
357 	/* sizes, item number */
358 	set_blkh_nr_item(blkh, nr + cpy_num);
359 	set_blkh_free_space(blkh, free_space - (j - last_inserted_loc));
360 
361 	do_balance_mark_leaf_dirty(dest_bi->tb, dest, 0);
362 
363 	if (dest_bi->bi_parent) {
364 		struct disk_child *t_dc;
365 		t_dc = B_N_CHILD(dest_bi->bi_parent, dest_bi->bi_position);
366 		RFALSE(dc_block_number(t_dc) != dest->b_blocknr,
367 		       "vs-10160: block number in bh does not match to field in disk_child structure %lu and %lu",
368 		       (long unsigned)dest->b_blocknr,
369 		       (long unsigned)dc_block_number(t_dc));
370 		put_dc_size(t_dc,
371 			    dc_size(t_dc) + (j - last_inserted_loc +
372 					     IH_SIZE * cpy_num));
373 
374 		do_balance_mark_internal_dirty(dest_bi->tb, dest_bi->bi_parent,
375 					       0);
376 	}
377 }
378 
379 /* This function splits the (liquid) item into two items (useful when
380    shifting part of an item into another node.) */
381 static void leaf_item_bottle(struct buffer_info *dest_bi,
382 			     struct buffer_head *src, int last_first,
383 			     int item_num, int cpy_bytes)
384 {
385 	struct buffer_head *dest = dest_bi->bi_bh;
386 	struct item_head *ih;
387 
388 	RFALSE(cpy_bytes == -1,
389 	       "vs-10170: bytes == - 1 means: do not split item");
390 
391 	if (last_first == FIRST_TO_LAST) {
392 		/* if ( if item in position item_num in buffer SOURCE is directory item ) */
393 		if (is_direntry_le_ih(ih = B_N_PITEM_HEAD(src, item_num)))
394 			leaf_copy_dir_entries(dest_bi, src, FIRST_TO_LAST,
395 					      item_num, 0, cpy_bytes);
396 		else {
397 			struct item_head n_ih;
398 
399 			/* copy part of the body of the item number 'item_num' of SOURCE to the end of the DEST
400 			   part defined by 'cpy_bytes'; create new item header; change old item_header (????);
401 			   n_ih = new item_header;
402 			 */
403 			memcpy(&n_ih, ih, IH_SIZE);
404 			put_ih_item_len(&n_ih, cpy_bytes);
405 			if (is_indirect_le_ih(ih)) {
406 				RFALSE(cpy_bytes == ih_item_len(ih)
407 				       && get_ih_free_space(ih),
408 				       "vs-10180: when whole indirect item is bottle to left neighbor, it must have free_space==0 (not %lu)",
409 				       (long unsigned)get_ih_free_space(ih));
410 				set_ih_free_space(&n_ih, 0);
411 			}
412 
413 			RFALSE(op_is_left_mergeable(&(ih->ih_key), src->b_size),
414 			       "vs-10190: bad mergeability of item %h", ih);
415 			n_ih.ih_version = ih->ih_version;	/* JDM Endian safe, both le */
416 			leaf_insert_into_buf(dest_bi, B_NR_ITEMS(dest), &n_ih,
417 					     B_N_PITEM(src, item_num), 0);
418 		}
419 	} else {
420 		/*  if ( if item in position item_num in buffer SOURCE is directory item ) */
421 		if (is_direntry_le_ih(ih = B_N_PITEM_HEAD(src, item_num)))
422 			leaf_copy_dir_entries(dest_bi, src, LAST_TO_FIRST,
423 					      item_num,
424 					      I_ENTRY_COUNT(ih) - cpy_bytes,
425 					      cpy_bytes);
426 		else {
427 			struct item_head n_ih;
428 
429 			/* copy part of the body of the item number 'item_num' of SOURCE to the begin of the DEST
430 			   part defined by 'cpy_bytes'; create new item header;
431 			   n_ih = new item_header;
432 			 */
433 			memcpy(&n_ih, ih, SHORT_KEY_SIZE);
434 
435 			n_ih.ih_version = ih->ih_version;	/* JDM Endian safe, both le */
436 
437 			if (is_direct_le_ih(ih)) {
438 				set_le_ih_k_offset(&n_ih,
439 						   le_ih_k_offset(ih) +
440 						   ih_item_len(ih) - cpy_bytes);
441 				set_le_ih_k_type(&n_ih, TYPE_DIRECT);
442 				set_ih_free_space(&n_ih, MAX_US_INT);
443 			} else {
444 				/* indirect item */
445 				RFALSE(!cpy_bytes && get_ih_free_space(ih),
446 				       "vs-10200: ih->ih_free_space must be 0 when indirect item will be appended");
447 				set_le_ih_k_offset(&n_ih,
448 						   le_ih_k_offset(ih) +
449 						   (ih_item_len(ih) -
450 						    cpy_bytes) / UNFM_P_SIZE *
451 						   dest->b_size);
452 				set_le_ih_k_type(&n_ih, TYPE_INDIRECT);
453 				set_ih_free_space(&n_ih, get_ih_free_space(ih));
454 			}
455 
456 			/* set item length */
457 			put_ih_item_len(&n_ih, cpy_bytes);
458 
459 			n_ih.ih_version = ih->ih_version;	/* JDM Endian safe, both le */
460 
461 			leaf_insert_into_buf(dest_bi, 0, &n_ih,
462 					     B_N_PITEM(src,
463 						       item_num) +
464 					     ih_item_len(ih) - cpy_bytes, 0);
465 		}
466 	}
467 }
468 
469 /* If cpy_bytes equals minus one than copy cpy_num whole items from SOURCE to DEST.
470    If cpy_bytes not equal to minus one than copy cpy_num-1 whole items from SOURCE to DEST.
471    From last item copy cpy_num bytes for regular item and cpy_num directory entries for
472    directory item. */
473 static int leaf_copy_items(struct buffer_info *dest_bi, struct buffer_head *src,
474 			   int last_first, int cpy_num, int cpy_bytes)
475 {
476 	struct buffer_head *dest;
477 	int pos, i, src_nr_item, bytes;
478 
479 	dest = dest_bi->bi_bh;
480 	RFALSE(!dest || !src, "vs-10210: !dest || !src");
481 	RFALSE(last_first != FIRST_TO_LAST && last_first != LAST_TO_FIRST,
482 	       "vs-10220:last_first != FIRST_TO_LAST && last_first != LAST_TO_FIRST");
483 	RFALSE(B_NR_ITEMS(src) < cpy_num,
484 	       "vs-10230: No enough items: %d, req. %d", B_NR_ITEMS(src),
485 	       cpy_num);
486 	RFALSE(cpy_num < 0, "vs-10240: cpy_num < 0 (%d)", cpy_num);
487 
488 	if (cpy_num == 0)
489 		return 0;
490 
491 	if (last_first == FIRST_TO_LAST) {
492 		/* copy items to left */
493 		pos = 0;
494 		if (cpy_num == 1)
495 			bytes = cpy_bytes;
496 		else
497 			bytes = -1;
498 
499 		/* copy the first item or it part or nothing to the end of the DEST (i = leaf_copy_boundary_item(DEST,SOURCE,0,bytes)) */
500 		i = leaf_copy_boundary_item(dest_bi, src, FIRST_TO_LAST, bytes);
501 		cpy_num -= i;
502 		if (cpy_num == 0)
503 			return i;
504 		pos += i;
505 		if (cpy_bytes == -1)
506 			/* copy first cpy_num items starting from position 'pos' of SOURCE to end of DEST */
507 			leaf_copy_items_entirely(dest_bi, src, FIRST_TO_LAST,
508 						 pos, cpy_num);
509 		else {
510 			/* copy first cpy_num-1 items starting from position 'pos-1' of the SOURCE to the end of the DEST */
511 			leaf_copy_items_entirely(dest_bi, src, FIRST_TO_LAST,
512 						 pos, cpy_num - 1);
513 
514 			/* copy part of the item which number is cpy_num+pos-1 to the end of the DEST */
515 			leaf_item_bottle(dest_bi, src, FIRST_TO_LAST,
516 					 cpy_num + pos - 1, cpy_bytes);
517 		}
518 	} else {
519 		/* copy items to right */
520 		src_nr_item = B_NR_ITEMS(src);
521 		if (cpy_num == 1)
522 			bytes = cpy_bytes;
523 		else
524 			bytes = -1;
525 
526 		/* copy the last item or it part or nothing to the begin of the DEST (i = leaf_copy_boundary_item(DEST,SOURCE,1,bytes)); */
527 		i = leaf_copy_boundary_item(dest_bi, src, LAST_TO_FIRST, bytes);
528 
529 		cpy_num -= i;
530 		if (cpy_num == 0)
531 			return i;
532 
533 		pos = src_nr_item - cpy_num - i;
534 		if (cpy_bytes == -1) {
535 			/* starting from position 'pos' copy last cpy_num items of SOURCE to begin of DEST */
536 			leaf_copy_items_entirely(dest_bi, src, LAST_TO_FIRST,
537 						 pos, cpy_num);
538 		} else {
539 			/* copy last cpy_num-1 items starting from position 'pos+1' of the SOURCE to the begin of the DEST; */
540 			leaf_copy_items_entirely(dest_bi, src, LAST_TO_FIRST,
541 						 pos + 1, cpy_num - 1);
542 
543 			/* copy part of the item which number is pos to the begin of the DEST */
544 			leaf_item_bottle(dest_bi, src, LAST_TO_FIRST, pos,
545 					 cpy_bytes);
546 		}
547 	}
548 	return i;
549 }
550 
551 /* there are types of coping: from S[0] to L[0], from S[0] to R[0],
552    from R[0] to L[0]. for each of these we have to define parent and
553    positions of destination and source buffers */
554 static void leaf_define_dest_src_infos(int shift_mode, struct tree_balance *tb,
555 				       struct buffer_info *dest_bi,
556 				       struct buffer_info *src_bi,
557 				       int *first_last,
558 				       struct buffer_head *Snew)
559 {
560 	memset(dest_bi, 0, sizeof(struct buffer_info));
561 	memset(src_bi, 0, sizeof(struct buffer_info));
562 
563 	/* define dest, src, dest parent, dest position */
564 	switch (shift_mode) {
565 	case LEAF_FROM_S_TO_L:	/* it is used in leaf_shift_left */
566 		src_bi->tb = tb;
567 		src_bi->bi_bh = PATH_PLAST_BUFFER(tb->tb_path);
568 		src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, 0);
569 		src_bi->bi_position = PATH_H_B_ITEM_ORDER(tb->tb_path, 0);	/* src->b_item_order */
570 		dest_bi->tb = tb;
571 		dest_bi->bi_bh = tb->L[0];
572 		dest_bi->bi_parent = tb->FL[0];
573 		dest_bi->bi_position = get_left_neighbor_position(tb, 0);
574 		*first_last = FIRST_TO_LAST;
575 		break;
576 
577 	case LEAF_FROM_S_TO_R:	/* it is used in leaf_shift_right */
578 		src_bi->tb = tb;
579 		src_bi->bi_bh = PATH_PLAST_BUFFER(tb->tb_path);
580 		src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, 0);
581 		src_bi->bi_position = PATH_H_B_ITEM_ORDER(tb->tb_path, 0);
582 		dest_bi->tb = tb;
583 		dest_bi->bi_bh = tb->R[0];
584 		dest_bi->bi_parent = tb->FR[0];
585 		dest_bi->bi_position = get_right_neighbor_position(tb, 0);
586 		*first_last = LAST_TO_FIRST;
587 		break;
588 
589 	case LEAF_FROM_R_TO_L:	/* it is used in balance_leaf_when_delete */
590 		src_bi->tb = tb;
591 		src_bi->bi_bh = tb->R[0];
592 		src_bi->bi_parent = tb->FR[0];
593 		src_bi->bi_position = get_right_neighbor_position(tb, 0);
594 		dest_bi->tb = tb;
595 		dest_bi->bi_bh = tb->L[0];
596 		dest_bi->bi_parent = tb->FL[0];
597 		dest_bi->bi_position = get_left_neighbor_position(tb, 0);
598 		*first_last = FIRST_TO_LAST;
599 		break;
600 
601 	case LEAF_FROM_L_TO_R:	/* it is used in balance_leaf_when_delete */
602 		src_bi->tb = tb;
603 		src_bi->bi_bh = tb->L[0];
604 		src_bi->bi_parent = tb->FL[0];
605 		src_bi->bi_position = get_left_neighbor_position(tb, 0);
606 		dest_bi->tb = tb;
607 		dest_bi->bi_bh = tb->R[0];
608 		dest_bi->bi_parent = tb->FR[0];
609 		dest_bi->bi_position = get_right_neighbor_position(tb, 0);
610 		*first_last = LAST_TO_FIRST;
611 		break;
612 
613 	case LEAF_FROM_S_TO_SNEW:
614 		src_bi->tb = tb;
615 		src_bi->bi_bh = PATH_PLAST_BUFFER(tb->tb_path);
616 		src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, 0);
617 		src_bi->bi_position = PATH_H_B_ITEM_ORDER(tb->tb_path, 0);
618 		dest_bi->tb = tb;
619 		dest_bi->bi_bh = Snew;
620 		dest_bi->bi_parent = NULL;
621 		dest_bi->bi_position = 0;
622 		*first_last = LAST_TO_FIRST;
623 		break;
624 
625 	default:
626 		reiserfs_panic(sb_from_bi(src_bi), "vs-10250",
627 			       "shift type is unknown (%d)", shift_mode);
628 	}
629 	RFALSE(!src_bi->bi_bh || !dest_bi->bi_bh,
630 	       "vs-10260: mode==%d, source (%p) or dest (%p) buffer is initialized incorrectly",
631 	       shift_mode, src_bi->bi_bh, dest_bi->bi_bh);
632 }
633 
634 /* copy mov_num items and mov_bytes of the (mov_num-1)th item to
635    neighbor. Delete them from source */
636 int leaf_move_items(int shift_mode, struct tree_balance *tb, int mov_num,
637 		    int mov_bytes, struct buffer_head *Snew)
638 {
639 	int ret_value;
640 	struct buffer_info dest_bi, src_bi;
641 	int first_last;
642 
643 	leaf_define_dest_src_infos(shift_mode, tb, &dest_bi, &src_bi,
644 				   &first_last, Snew);
645 
646 	ret_value =
647 	    leaf_copy_items(&dest_bi, src_bi.bi_bh, first_last, mov_num,
648 			    mov_bytes);
649 
650 	leaf_delete_items(&src_bi, first_last,
651 			  (first_last ==
652 			   FIRST_TO_LAST) ? 0 : (B_NR_ITEMS(src_bi.bi_bh) -
653 						 mov_num), mov_num, mov_bytes);
654 
655 	return ret_value;
656 }
657 
658 /* Shift shift_num items (and shift_bytes of last shifted item if shift_bytes != -1)
659    from S[0] to L[0] and replace the delimiting key */
660 int leaf_shift_left(struct tree_balance *tb, int shift_num, int shift_bytes)
661 {
662 	struct buffer_head *S0 = PATH_PLAST_BUFFER(tb->tb_path);
663 	int i;
664 
665 	/* move shift_num (and shift_bytes bytes) items from S[0] to left neighbor L[0] */
666 	i = leaf_move_items(LEAF_FROM_S_TO_L, tb, shift_num, shift_bytes, NULL);
667 
668 	if (shift_num) {
669 		if (B_NR_ITEMS(S0) == 0) {	/* number of items in S[0] == 0 */
670 
671 			RFALSE(shift_bytes != -1,
672 			       "vs-10270: S0 is empty now, but shift_bytes != -1 (%d)",
673 			       shift_bytes);
674 #ifdef CONFIG_REISERFS_CHECK
675 			if (tb->tb_mode == M_PASTE || tb->tb_mode == M_INSERT) {
676 				print_cur_tb("vs-10275");
677 				reiserfs_panic(tb->tb_sb, "vs-10275",
678 					       "balance condition corrupted "
679 					       "(%c)", tb->tb_mode);
680 			}
681 #endif
682 
683 			if (PATH_H_POSITION(tb->tb_path, 1) == 0)
684 				replace_key(tb, tb->CFL[0], tb->lkey[0],
685 					    PATH_H_PPARENT(tb->tb_path, 0), 0);
686 
687 		} else {
688 			/* replace lkey in CFL[0] by 0-th key from S[0]; */
689 			replace_key(tb, tb->CFL[0], tb->lkey[0], S0, 0);
690 
691 			RFALSE((shift_bytes != -1 &&
692 				!(is_direntry_le_ih(B_N_PITEM_HEAD(S0, 0))
693 				  && !I_ENTRY_COUNT(B_N_PITEM_HEAD(S0, 0)))) &&
694 			       (!op_is_left_mergeable
695 				(B_N_PKEY(S0, 0), S0->b_size)),
696 			       "vs-10280: item must be mergeable");
697 		}
698 	}
699 
700 	return i;
701 }
702 
703 /* CLEANING STOPPED HERE */
704 
705 /* Shift shift_num (shift_bytes) items from S[0] to the right neighbor, and replace the delimiting key */
706 int leaf_shift_right(struct tree_balance *tb, int shift_num, int shift_bytes)
707 {
708 	//  struct buffer_head * S0 = PATH_PLAST_BUFFER (tb->tb_path);
709 	int ret_value;
710 
711 	/* move shift_num (and shift_bytes) items from S[0] to right neighbor R[0] */
712 	ret_value =
713 	    leaf_move_items(LEAF_FROM_S_TO_R, tb, shift_num, shift_bytes, NULL);
714 
715 	/* replace rkey in CFR[0] by the 0-th key from R[0] */
716 	if (shift_num) {
717 		replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
718 
719 	}
720 
721 	return ret_value;
722 }
723 
724 static void leaf_delete_items_entirely(struct buffer_info *bi,
725 				       int first, int del_num);
726 /*  If del_bytes == -1, starting from position 'first' delete del_num items in whole in buffer CUR.
727     If not.
728     If last_first == 0. Starting from position 'first' delete del_num-1 items in whole. Delete part of body of
729     the first item. Part defined by del_bytes. Don't delete first item header
730     If last_first == 1. Starting from position 'first+1' delete del_num-1 items in whole. Delete part of body of
731     the last item . Part defined by del_bytes. Don't delete last item header.
732 */
733 void leaf_delete_items(struct buffer_info *cur_bi, int last_first,
734 		       int first, int del_num, int del_bytes)
735 {
736 	struct buffer_head *bh;
737 	int item_amount = B_NR_ITEMS(bh = cur_bi->bi_bh);
738 
739 	RFALSE(!bh, "10155: bh is not defined");
740 	RFALSE(del_num < 0, "10160: del_num can not be < 0. del_num==%d",
741 	       del_num);
742 	RFALSE(first < 0
743 	       || first + del_num > item_amount,
744 	       "10165: invalid number of first item to be deleted (%d) or "
745 	       "no so much items (%d) to delete (only %d)", first,
746 	       first + del_num, item_amount);
747 
748 	if (del_num == 0)
749 		return;
750 
751 	if (first == 0 && del_num == item_amount && del_bytes == -1) {
752 		make_empty_node(cur_bi);
753 		do_balance_mark_leaf_dirty(cur_bi->tb, bh, 0);
754 		return;
755 	}
756 
757 	if (del_bytes == -1)
758 		/* delete del_num items beginning from item in position first */
759 		leaf_delete_items_entirely(cur_bi, first, del_num);
760 	else {
761 		if (last_first == FIRST_TO_LAST) {
762 			/* delete del_num-1 items beginning from item in position first  */
763 			leaf_delete_items_entirely(cur_bi, first, del_num - 1);
764 
765 			/* delete the part of the first item of the bh
766 			   do not delete item header
767 			 */
768 			leaf_cut_from_buffer(cur_bi, 0, 0, del_bytes);
769 		} else {
770 			struct item_head *ih;
771 			int len;
772 
773 			/* delete del_num-1 items beginning from item in position first+1  */
774 			leaf_delete_items_entirely(cur_bi, first + 1,
775 						   del_num - 1);
776 
777 			if (is_direntry_le_ih
778 			    (ih = B_N_PITEM_HEAD(bh, B_NR_ITEMS(bh) - 1)))
779 				/* the last item is directory  */
780 				/* len = numbers of directory entries in this item */
781 				len = ih_entry_count(ih);
782 			else
783 				/* len = body len of item */
784 				len = ih_item_len(ih);
785 
786 			/* delete the part of the last item of the bh
787 			   do not delete item header
788 			 */
789 			leaf_cut_from_buffer(cur_bi, B_NR_ITEMS(bh) - 1,
790 					     len - del_bytes, del_bytes);
791 		}
792 	}
793 }
794 
795 /* insert item into the leaf node in position before */
796 void leaf_insert_into_buf(struct buffer_info *bi, int before,
797 			  struct item_head *inserted_item_ih,
798 			  const char *inserted_item_body, int zeros_number)
799 {
800 	struct buffer_head *bh = bi->bi_bh;
801 	int nr, free_space;
802 	struct block_head *blkh;
803 	struct item_head *ih;
804 	int i;
805 	int last_loc, unmoved_loc;
806 	char *to;
807 
808 	blkh = B_BLK_HEAD(bh);
809 	nr = blkh_nr_item(blkh);
810 	free_space = blkh_free_space(blkh);
811 
812 	/* check free space */
813 	RFALSE(free_space < ih_item_len(inserted_item_ih) + IH_SIZE,
814 	       "vs-10170: not enough free space in block %z, new item %h",
815 	       bh, inserted_item_ih);
816 	RFALSE(zeros_number > ih_item_len(inserted_item_ih),
817 	       "vs-10172: zero number == %d, item length == %d",
818 	       zeros_number, ih_item_len(inserted_item_ih));
819 
820 	/* get item new item must be inserted before */
821 	ih = B_N_PITEM_HEAD(bh, before);
822 
823 	/* prepare space for the body of new item */
824 	last_loc = nr ? ih_location(&(ih[nr - before - 1])) : bh->b_size;
825 	unmoved_loc = before ? ih_location(ih - 1) : bh->b_size;
826 
827 	memmove(bh->b_data + last_loc - ih_item_len(inserted_item_ih),
828 		bh->b_data + last_loc, unmoved_loc - last_loc);
829 
830 	to = bh->b_data + unmoved_loc - ih_item_len(inserted_item_ih);
831 	memset(to, 0, zeros_number);
832 	to += zeros_number;
833 
834 	/* copy body to prepared space */
835 	if (inserted_item_body)
836 		memmove(to, inserted_item_body,
837 			ih_item_len(inserted_item_ih) - zeros_number);
838 	else
839 		memset(to, '\0', ih_item_len(inserted_item_ih) - zeros_number);
840 
841 	/* insert item header */
842 	memmove(ih + 1, ih, IH_SIZE * (nr - before));
843 	memmove(ih, inserted_item_ih, IH_SIZE);
844 
845 	/* change locations */
846 	for (i = before; i < nr + 1; i++) {
847 		unmoved_loc -= ih_item_len(&(ih[i - before]));
848 		put_ih_location(&(ih[i - before]), unmoved_loc);
849 	}
850 
851 	/* sizes, free space, item number */
852 	set_blkh_nr_item(blkh, blkh_nr_item(blkh) + 1);
853 	set_blkh_free_space(blkh,
854 			    free_space - (IH_SIZE +
855 					  ih_item_len(inserted_item_ih)));
856 	do_balance_mark_leaf_dirty(bi->tb, bh, 1);
857 
858 	if (bi->bi_parent) {
859 		struct disk_child *t_dc;
860 		t_dc = B_N_CHILD(bi->bi_parent, bi->bi_position);
861 		put_dc_size(t_dc,
862 			    dc_size(t_dc) + (IH_SIZE +
863 					     ih_item_len(inserted_item_ih)));
864 		do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
865 	}
866 }
867 
868 /* paste paste_size bytes to affected_item_num-th item.
869    When item is a directory, this only prepare space for new entries */
870 void leaf_paste_in_buffer(struct buffer_info *bi, int affected_item_num,
871 			  int pos_in_item, int paste_size,
872 			  const char *body, int zeros_number)
873 {
874 	struct buffer_head *bh = bi->bi_bh;
875 	int nr, free_space;
876 	struct block_head *blkh;
877 	struct item_head *ih;
878 	int i;
879 	int last_loc, unmoved_loc;
880 
881 	blkh = B_BLK_HEAD(bh);
882 	nr = blkh_nr_item(blkh);
883 	free_space = blkh_free_space(blkh);
884 
885 	/* check free space */
886 	RFALSE(free_space < paste_size,
887 	       "vs-10175: not enough free space: needed %d, available %d",
888 	       paste_size, free_space);
889 
890 #ifdef CONFIG_REISERFS_CHECK
891 	if (zeros_number > paste_size) {
892 		struct super_block *sb = NULL;
893 		if (bi && bi->tb)
894 			sb = bi->tb->tb_sb;
895 		print_cur_tb("10177");
896 		reiserfs_panic(sb, "vs-10177",
897 			       "zeros_number == %d, paste_size == %d",
898 			       zeros_number, paste_size);
899 	}
900 #endif				/* CONFIG_REISERFS_CHECK */
901 
902 	/* item to be appended */
903 	ih = B_N_PITEM_HEAD(bh, affected_item_num);
904 
905 	last_loc = ih_location(&(ih[nr - affected_item_num - 1]));
906 	unmoved_loc = affected_item_num ? ih_location(ih - 1) : bh->b_size;
907 
908 	/* prepare space */
909 	memmove(bh->b_data + last_loc - paste_size, bh->b_data + last_loc,
910 		unmoved_loc - last_loc);
911 
912 	/* change locations */
913 	for (i = affected_item_num; i < nr; i++)
914 		put_ih_location(&(ih[i - affected_item_num]),
915 				ih_location(&(ih[i - affected_item_num])) -
916 				paste_size);
917 
918 	if (body) {
919 		if (!is_direntry_le_ih(ih)) {
920 			if (!pos_in_item) {
921 				/* shift data to right */
922 				memmove(bh->b_data + ih_location(ih) +
923 					paste_size,
924 					bh->b_data + ih_location(ih),
925 					ih_item_len(ih));
926 				/* paste data in the head of item */
927 				memset(bh->b_data + ih_location(ih), 0,
928 				       zeros_number);
929 				memcpy(bh->b_data + ih_location(ih) +
930 				       zeros_number, body,
931 				       paste_size - zeros_number);
932 			} else {
933 				memset(bh->b_data + unmoved_loc - paste_size, 0,
934 				       zeros_number);
935 				memcpy(bh->b_data + unmoved_loc - paste_size +
936 				       zeros_number, body,
937 				       paste_size - zeros_number);
938 			}
939 		}
940 	} else
941 		memset(bh->b_data + unmoved_loc - paste_size, '\0', paste_size);
942 
943 	put_ih_item_len(ih, ih_item_len(ih) + paste_size);
944 
945 	/* change free space */
946 	set_blkh_free_space(blkh, free_space - paste_size);
947 
948 	do_balance_mark_leaf_dirty(bi->tb, bh, 0);
949 
950 	if (bi->bi_parent) {
951 		struct disk_child *t_dc =
952 		    B_N_CHILD(bi->bi_parent, bi->bi_position);
953 		put_dc_size(t_dc, dc_size(t_dc) + paste_size);
954 		do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
955 	}
956 }
957 
958 /* cuts DEL_COUNT entries beginning from FROM-th entry. Directory item
959    does not have free space, so it moves DEHs and remaining records as
960    necessary. Return value is size of removed part of directory item
961    in bytes. */
962 static int leaf_cut_entries(struct buffer_head *bh,
963 			    struct item_head *ih, int from, int del_count)
964 {
965 	char *item;
966 	struct reiserfs_de_head *deh;
967 	int prev_record_offset;	/* offset of record, that is (from-1)th */
968 	char *prev_record;	/* */
969 	int cut_records_len;	/* length of all removed records */
970 	int i;
971 
972 	/* make sure, that item is directory and there are enough entries to
973 	   remove */
974 	RFALSE(!is_direntry_le_ih(ih), "10180: item is not directory item");
975 	RFALSE(I_ENTRY_COUNT(ih) < from + del_count,
976 	       "10185: item contains not enough entries: entry_cout = %d, from = %d, to delete = %d",
977 	       I_ENTRY_COUNT(ih), from, del_count);
978 
979 	if (del_count == 0)
980 		return 0;
981 
982 	/* first byte of item */
983 	item = bh->b_data + ih_location(ih);
984 
985 	/* entry head array */
986 	deh = B_I_DEH(bh, ih);
987 
988 	/* first byte of remaining entries, those are BEFORE cut entries
989 	   (prev_record) and length of all removed records (cut_records_len) */
990 	prev_record_offset =
991 	    (from ? deh_location(&(deh[from - 1])) : ih_item_len(ih));
992 	cut_records_len = prev_record_offset /*from_record */  -
993 	    deh_location(&(deh[from + del_count - 1]));
994 	prev_record = item + prev_record_offset;
995 
996 	/* adjust locations of remaining entries */
997 	for (i = I_ENTRY_COUNT(ih) - 1; i > from + del_count - 1; i--)
998 		put_deh_location(&(deh[i]),
999 				 deh_location(&deh[i]) -
1000 				 (DEH_SIZE * del_count));
1001 
1002 	for (i = 0; i < from; i++)
1003 		put_deh_location(&(deh[i]),
1004 				 deh_location(&deh[i]) - (DEH_SIZE * del_count +
1005 							  cut_records_len));
1006 
1007 	put_ih_entry_count(ih, ih_entry_count(ih) - del_count);
1008 
1009 	/* shift entry head array and entries those are AFTER removed entries */
1010 	memmove((char *)(deh + from),
1011 		deh + from + del_count,
1012 		prev_record - cut_records_len - (char *)(deh + from +
1013 							 del_count));
1014 
1015 	/* shift records, those are BEFORE removed entries */
1016 	memmove(prev_record - cut_records_len - DEH_SIZE * del_count,
1017 		prev_record, item + ih_item_len(ih) - prev_record);
1018 
1019 	return DEH_SIZE * del_count + cut_records_len;
1020 }
1021 
1022 /*  when cut item is part of regular file
1023         pos_in_item - first byte that must be cut
1024         cut_size - number of bytes to be cut beginning from pos_in_item
1025 
1026    when cut item is part of directory
1027         pos_in_item - number of first deleted entry
1028         cut_size - count of deleted entries
1029     */
1030 void leaf_cut_from_buffer(struct buffer_info *bi, int cut_item_num,
1031 			  int pos_in_item, int cut_size)
1032 {
1033 	int nr;
1034 	struct buffer_head *bh = bi->bi_bh;
1035 	struct block_head *blkh;
1036 	struct item_head *ih;
1037 	int last_loc, unmoved_loc;
1038 	int i;
1039 
1040 	blkh = B_BLK_HEAD(bh);
1041 	nr = blkh_nr_item(blkh);
1042 
1043 	/* item head of truncated item */
1044 	ih = B_N_PITEM_HEAD(bh, cut_item_num);
1045 
1046 	if (is_direntry_le_ih(ih)) {
1047 		/* first cut entry () */
1048 		cut_size = leaf_cut_entries(bh, ih, pos_in_item, cut_size);
1049 		if (pos_in_item == 0) {
1050 			/* change key */
1051 			RFALSE(cut_item_num,
1052 			       "when 0-th enrty of item is cut, that item must be first in the node, not %d-th",
1053 			       cut_item_num);
1054 			/* change item key by key of first entry in the item */
1055 			set_le_ih_k_offset(ih, deh_offset(B_I_DEH(bh, ih)));
1056 			/*memcpy (&ih->ih_key.k_offset, &(B_I_DEH (bh, ih)->deh_offset), SHORT_KEY_SIZE); */
1057 		}
1058 	} else {
1059 		/* item is direct or indirect */
1060 		RFALSE(is_statdata_le_ih(ih), "10195: item is stat data");
1061 		RFALSE(pos_in_item && pos_in_item + cut_size != ih_item_len(ih),
1062 		       "10200: invalid offset (%lu) or trunc_size (%lu) or ih_item_len (%lu)",
1063 		       (long unsigned)pos_in_item, (long unsigned)cut_size,
1064 		       (long unsigned)ih_item_len(ih));
1065 
1066 		/* shift item body to left if cut is from the head of item */
1067 		if (pos_in_item == 0) {
1068 			memmove(bh->b_data + ih_location(ih),
1069 				bh->b_data + ih_location(ih) + cut_size,
1070 				ih_item_len(ih) - cut_size);
1071 
1072 			/* change key of item */
1073 			if (is_direct_le_ih(ih))
1074 				set_le_ih_k_offset(ih,
1075 						   le_ih_k_offset(ih) +
1076 						   cut_size);
1077 			else {
1078 				set_le_ih_k_offset(ih,
1079 						   le_ih_k_offset(ih) +
1080 						   (cut_size / UNFM_P_SIZE) *
1081 						   bh->b_size);
1082 				RFALSE(ih_item_len(ih) == cut_size
1083 				       && get_ih_free_space(ih),
1084 				       "10205: invalid ih_free_space (%h)", ih);
1085 			}
1086 		}
1087 	}
1088 
1089 	/* location of the last item */
1090 	last_loc = ih_location(&(ih[nr - cut_item_num - 1]));
1091 
1092 	/* location of the item, which is remaining at the same place */
1093 	unmoved_loc = cut_item_num ? ih_location(ih - 1) : bh->b_size;
1094 
1095 	/* shift */
1096 	memmove(bh->b_data + last_loc + cut_size, bh->b_data + last_loc,
1097 		unmoved_loc - last_loc - cut_size);
1098 
1099 	/* change item length */
1100 	put_ih_item_len(ih, ih_item_len(ih) - cut_size);
1101 
1102 	if (is_indirect_le_ih(ih)) {
1103 		if (pos_in_item)
1104 			set_ih_free_space(ih, 0);
1105 	}
1106 
1107 	/* change locations */
1108 	for (i = cut_item_num; i < nr; i++)
1109 		put_ih_location(&(ih[i - cut_item_num]),
1110 				ih_location(&ih[i - cut_item_num]) + cut_size);
1111 
1112 	/* size, free space */
1113 	set_blkh_free_space(blkh, blkh_free_space(blkh) + cut_size);
1114 
1115 	do_balance_mark_leaf_dirty(bi->tb, bh, 0);
1116 
1117 	if (bi->bi_parent) {
1118 		struct disk_child *t_dc;
1119 		t_dc = B_N_CHILD(bi->bi_parent, bi->bi_position);
1120 		put_dc_size(t_dc, dc_size(t_dc) - cut_size);
1121 		do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
1122 	}
1123 }
1124 
1125 /* delete del_num items from buffer starting from the first'th item */
1126 static void leaf_delete_items_entirely(struct buffer_info *bi,
1127 				       int first, int del_num)
1128 {
1129 	struct buffer_head *bh = bi->bi_bh;
1130 	int nr;
1131 	int i, j;
1132 	int last_loc, last_removed_loc;
1133 	struct block_head *blkh;
1134 	struct item_head *ih;
1135 
1136 	RFALSE(bh == NULL, "10210: buffer is 0");
1137 	RFALSE(del_num < 0, "10215: del_num less than 0 (%d)", del_num);
1138 
1139 	if (del_num == 0)
1140 		return;
1141 
1142 	blkh = B_BLK_HEAD(bh);
1143 	nr = blkh_nr_item(blkh);
1144 
1145 	RFALSE(first < 0 || first + del_num > nr,
1146 	       "10220: first=%d, number=%d, there is %d items", first, del_num,
1147 	       nr);
1148 
1149 	if (first == 0 && del_num == nr) {
1150 		/* this does not work */
1151 		make_empty_node(bi);
1152 
1153 		do_balance_mark_leaf_dirty(bi->tb, bh, 0);
1154 		return;
1155 	}
1156 
1157 	ih = B_N_PITEM_HEAD(bh, first);
1158 
1159 	/* location of unmovable item */
1160 	j = (first == 0) ? bh->b_size : ih_location(ih - 1);
1161 
1162 	/* delete items */
1163 	last_loc = ih_location(&(ih[nr - 1 - first]));
1164 	last_removed_loc = ih_location(&(ih[del_num - 1]));
1165 
1166 	memmove(bh->b_data + last_loc + j - last_removed_loc,
1167 		bh->b_data + last_loc, last_removed_loc - last_loc);
1168 
1169 	/* delete item headers */
1170 	memmove(ih, ih + del_num, (nr - first - del_num) * IH_SIZE);
1171 
1172 	/* change item location */
1173 	for (i = first; i < nr - del_num; i++)
1174 		put_ih_location(&(ih[i - first]),
1175 				ih_location(&(ih[i - first])) + (j -
1176 								 last_removed_loc));
1177 
1178 	/* sizes, item number */
1179 	set_blkh_nr_item(blkh, blkh_nr_item(blkh) - del_num);
1180 	set_blkh_free_space(blkh,
1181 			    blkh_free_space(blkh) + (j - last_removed_loc +
1182 						     IH_SIZE * del_num));
1183 
1184 	do_balance_mark_leaf_dirty(bi->tb, bh, 0);
1185 
1186 	if (bi->bi_parent) {
1187 		struct disk_child *t_dc =
1188 		    B_N_CHILD(bi->bi_parent, bi->bi_position);
1189 		put_dc_size(t_dc,
1190 			    dc_size(t_dc) - (j - last_removed_loc +
1191 					     IH_SIZE * del_num));
1192 		do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
1193 	}
1194 }
1195 
1196 /* paste new_entry_count entries (new_dehs, records) into position before to item_num-th item */
1197 void leaf_paste_entries(struct buffer_info *bi,
1198 			int item_num,
1199 			int before,
1200 			int new_entry_count,
1201 			struct reiserfs_de_head *new_dehs,
1202 			const char *records, int paste_size)
1203 {
1204 	struct item_head *ih;
1205 	char *item;
1206 	struct reiserfs_de_head *deh;
1207 	char *insert_point;
1208 	int i, old_entry_num;
1209 	struct buffer_head *bh = bi->bi_bh;
1210 
1211 	if (new_entry_count == 0)
1212 		return;
1213 
1214 	ih = B_N_PITEM_HEAD(bh, item_num);
1215 
1216 	/* make sure, that item is directory, and there are enough records in it */
1217 	RFALSE(!is_direntry_le_ih(ih), "10225: item is not directory item");
1218 	RFALSE(I_ENTRY_COUNT(ih) < before,
1219 	       "10230: there are no entry we paste entries before. entry_count = %d, before = %d",
1220 	       I_ENTRY_COUNT(ih), before);
1221 
1222 	/* first byte of dest item */
1223 	item = bh->b_data + ih_location(ih);
1224 
1225 	/* entry head array */
1226 	deh = B_I_DEH(bh, ih);
1227 
1228 	/* new records will be pasted at this point */
1229 	insert_point =
1230 	    item +
1231 	    (before ? deh_location(&(deh[before - 1]))
1232 	     : (ih_item_len(ih) - paste_size));
1233 
1234 	/* adjust locations of records that will be AFTER new records */
1235 	for (i = I_ENTRY_COUNT(ih) - 1; i >= before; i--)
1236 		put_deh_location(&(deh[i]),
1237 				 deh_location(&(deh[i])) +
1238 				 (DEH_SIZE * new_entry_count));
1239 
1240 	/* adjust locations of records that will be BEFORE new records */
1241 	for (i = 0; i < before; i++)
1242 		put_deh_location(&(deh[i]),
1243 				 deh_location(&(deh[i])) + paste_size);
1244 
1245 	old_entry_num = I_ENTRY_COUNT(ih);
1246 	put_ih_entry_count(ih, ih_entry_count(ih) + new_entry_count);
1247 
1248 	/* prepare space for pasted records */
1249 	memmove(insert_point + paste_size, insert_point,
1250 		item + (ih_item_len(ih) - paste_size) - insert_point);
1251 
1252 	/* copy new records */
1253 	memcpy(insert_point + DEH_SIZE * new_entry_count, records,
1254 	       paste_size - DEH_SIZE * new_entry_count);
1255 
1256 	/* prepare space for new entry heads */
1257 	deh += before;
1258 	memmove((char *)(deh + new_entry_count), deh,
1259 		insert_point - (char *)deh);
1260 
1261 	/* copy new entry heads */
1262 	deh = (struct reiserfs_de_head *)((char *)deh);
1263 	memcpy(deh, new_dehs, DEH_SIZE * new_entry_count);
1264 
1265 	/* set locations of new records */
1266 	for (i = 0; i < new_entry_count; i++) {
1267 		put_deh_location(&(deh[i]),
1268 				 deh_location(&(deh[i])) +
1269 				 (-deh_location
1270 				  (&(new_dehs[new_entry_count - 1])) +
1271 				  insert_point + DEH_SIZE * new_entry_count -
1272 				  item));
1273 	}
1274 
1275 	/* change item key if necessary (when we paste before 0-th entry */
1276 	if (!before) {
1277 		set_le_ih_k_offset(ih, deh_offset(new_dehs));
1278 /*      memcpy (&ih->ih_key.k_offset,
1279 		       &new_dehs->deh_offset, SHORT_KEY_SIZE);*/
1280 	}
1281 #ifdef CONFIG_REISERFS_CHECK
1282 	{
1283 		int prev, next;
1284 		/* check record locations */
1285 		deh = B_I_DEH(bh, ih);
1286 		for (i = 0; i < I_ENTRY_COUNT(ih); i++) {
1287 			next =
1288 			    (i <
1289 			     I_ENTRY_COUNT(ih) -
1290 			     1) ? deh_location(&(deh[i + 1])) : 0;
1291 			prev = (i != 0) ? deh_location(&(deh[i - 1])) : 0;
1292 
1293 			if (prev && prev <= deh_location(&(deh[i])))
1294 				reiserfs_error(sb_from_bi(bi), "vs-10240",
1295 					       "directory item (%h) "
1296 					       "corrupted (prev %a, "
1297 					       "cur(%d) %a)",
1298 					       ih, deh + i - 1, i, deh + i);
1299 			if (next && next >= deh_location(&(deh[i])))
1300 				reiserfs_error(sb_from_bi(bi), "vs-10250",
1301 					       "directory item (%h) "
1302 					       "corrupted (cur(%d) %a, "
1303 					       "next %a)",
1304 					       ih, i, deh + i, deh + i + 1);
1305 		}
1306 	}
1307 #endif
1308 
1309 }
1310