xref: /openbmc/linux/fs/reiserfs/lbalance.c (revision 87c2ce3b)
1 /*
2  * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3  */
4 
5 #include <linux/config.h>
6 #include <asm/uaccess.h>
7 #include <linux/string.h>
8 #include <linux/time.h>
9 #include <linux/reiserfs_fs.h>
10 #include <linux/buffer_head.h>
11 
12 /* these are used in do_balance.c */
13 
14 /* leaf_move_items
15    leaf_shift_left
16    leaf_shift_right
17    leaf_delete_items
18    leaf_insert_into_buf
19    leaf_paste_in_buffer
20    leaf_cut_from_buffer
21    leaf_paste_entries
22    */
23 
24 /* copy copy_count entries from source directory item to dest buffer (creating new item if needed) */
25 static void leaf_copy_dir_entries(struct buffer_info *dest_bi,
26 				  struct buffer_head *source, int last_first,
27 				  int item_num, int from, int copy_count)
28 {
29 	struct buffer_head *dest = dest_bi->bi_bh;
30 	int item_num_in_dest;	/* either the number of target item,
31 				   or if we must create a new item,
32 				   the number of the item we will
33 				   create it next to */
34 	struct item_head *ih;
35 	struct reiserfs_de_head *deh;
36 	int copy_records_len;	/* length of all records in item to be copied */
37 	char *records;
38 
39 	ih = B_N_PITEM_HEAD(source, item_num);
40 
41 	RFALSE(!is_direntry_le_ih(ih), "vs-10000: item must be directory item");
42 
43 	/* length of all record to be copied and first byte of the last of them */
44 	deh = B_I_DEH(source, ih);
45 	if (copy_count) {
46 		copy_records_len = (from ? deh_location(&(deh[from - 1])) :
47 				    ih_item_len(ih)) -
48 		    deh_location(&(deh[from + copy_count - 1]));
49 		records =
50 		    source->b_data + ih_location(ih) +
51 		    deh_location(&(deh[from + copy_count - 1]));
52 	} else {
53 		copy_records_len = 0;
54 		records = NULL;
55 	}
56 
57 	/* when copy last to first, dest buffer can contain 0 items */
58 	item_num_in_dest =
59 	    (last_first ==
60 	     LAST_TO_FIRST) ? ((B_NR_ITEMS(dest)) ? 0 : -1) : (B_NR_ITEMS(dest)
61 							       - 1);
62 
63 	/* if there are no items in dest or the first/last item in dest is not item of the same directory */
64 	if ((item_num_in_dest == -1) ||
65 	    (last_first == FIRST_TO_LAST && le_ih_k_offset(ih) == DOT_OFFSET) ||
66 	    (last_first == LAST_TO_FIRST
67 	     && comp_short_le_keys /*COMP_SHORT_KEYS */ (&ih->ih_key,
68 							 B_N_PKEY(dest,
69 								  item_num_in_dest))))
70 	{
71 		/* create new item in dest */
72 		struct item_head new_ih;
73 
74 		/* form item header */
75 		memcpy(&new_ih.ih_key, &ih->ih_key, KEY_SIZE);
76 		put_ih_version(&new_ih, KEY_FORMAT_3_5);
77 		/* calculate item len */
78 		put_ih_item_len(&new_ih,
79 				DEH_SIZE * copy_count + copy_records_len);
80 		put_ih_entry_count(&new_ih, 0);
81 
82 		if (last_first == LAST_TO_FIRST) {
83 			/* form key by the following way */
84 			if (from < I_ENTRY_COUNT(ih)) {
85 				set_le_ih_k_offset(&new_ih,
86 						   deh_offset(&(deh[from])));
87 				/*memcpy (&new_ih.ih_key.k_offset, &deh[from].deh_offset, SHORT_KEY_SIZE); */
88 			} else {
89 				/* no entries will be copied to this item in this function */
90 				set_le_ih_k_offset(&new_ih, U32_MAX);
91 				/* this item is not yet valid, but we want I_IS_DIRECTORY_ITEM to return 1 for it, so we -1 */
92 			}
93 			set_le_key_k_type(KEY_FORMAT_3_5, &(new_ih.ih_key),
94 					  TYPE_DIRENTRY);
95 		}
96 
97 		/* insert item into dest buffer */
98 		leaf_insert_into_buf(dest_bi,
99 				     (last_first ==
100 				      LAST_TO_FIRST) ? 0 : B_NR_ITEMS(dest),
101 				     &new_ih, NULL, 0);
102 	} else {
103 		/* prepare space for entries */
104 		leaf_paste_in_buffer(dest_bi,
105 				     (last_first ==
106 				      FIRST_TO_LAST) ? (B_NR_ITEMS(dest) -
107 							1) : 0, MAX_US_INT,
108 				     DEH_SIZE * copy_count + copy_records_len,
109 				     records, 0);
110 	}
111 
112 	item_num_in_dest =
113 	    (last_first == FIRST_TO_LAST) ? (B_NR_ITEMS(dest) - 1) : 0;
114 
115 	leaf_paste_entries(dest_bi->bi_bh, item_num_in_dest,
116 			   (last_first ==
117 			    FIRST_TO_LAST) ? I_ENTRY_COUNT(B_N_PITEM_HEAD(dest,
118 									  item_num_in_dest))
119 			   : 0, copy_count, deh + from, records,
120 			   DEH_SIZE * copy_count + copy_records_len);
121 }
122 
123 /* Copy the first (if last_first == FIRST_TO_LAST) or last (last_first == LAST_TO_FIRST) item or
124    part of it or nothing (see the return 0 below) from SOURCE to the end
125    (if last_first) or beginning (!last_first) of the DEST */
126 /* returns 1 if anything was copied, else 0 */
127 static int leaf_copy_boundary_item(struct buffer_info *dest_bi,
128 				   struct buffer_head *src, int last_first,
129 				   int bytes_or_entries)
130 {
131 	struct buffer_head *dest = dest_bi->bi_bh;
132 	int dest_nr_item, src_nr_item;	/* number of items in the source and destination buffers */
133 	struct item_head *ih;
134 	struct item_head *dih;
135 
136 	dest_nr_item = B_NR_ITEMS(dest);
137 
138 	if (last_first == FIRST_TO_LAST) {
139 		/* if ( DEST is empty or first item of SOURCE and last item of DEST are the items of different objects
140 		   or of different types ) then there is no need to treat this item differently from the other items
141 		   that we copy, so we return */
142 		ih = B_N_PITEM_HEAD(src, 0);
143 		dih = B_N_PITEM_HEAD(dest, dest_nr_item - 1);
144 		if (!dest_nr_item
145 		    || (!op_is_left_mergeable(&(ih->ih_key), src->b_size)))
146 			/* there is nothing to merge */
147 			return 0;
148 
149 		RFALSE(!ih_item_len(ih),
150 		       "vs-10010: item can not have empty length");
151 
152 		if (is_direntry_le_ih(ih)) {
153 			if (bytes_or_entries == -1)
154 				/* copy all entries to dest */
155 				bytes_or_entries = ih_entry_count(ih);
156 			leaf_copy_dir_entries(dest_bi, src, FIRST_TO_LAST, 0, 0,
157 					      bytes_or_entries);
158 			return 1;
159 		}
160 
161 		/* copy part of the body of the first item of SOURCE to the end of the body of the last item of the DEST
162 		   part defined by 'bytes_or_entries'; if bytes_or_entries == -1 copy whole body; don't create new item header
163 		 */
164 		if (bytes_or_entries == -1)
165 			bytes_or_entries = ih_item_len(ih);
166 
167 #ifdef CONFIG_REISERFS_CHECK
168 		else {
169 			if (bytes_or_entries == ih_item_len(ih)
170 			    && is_indirect_le_ih(ih))
171 				if (get_ih_free_space(ih))
172 					reiserfs_panic(NULL,
173 						       "vs-10020: leaf_copy_boundary_item: "
174 						       "last unformatted node must be filled entirely (%h)",
175 						       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(NULL,
627 			       "vs-10250: leaf_define_dest_src_infos: shift type is unknown (%d)",
628 			       shift_mode);
629 	}
630 	RFALSE(src_bi->bi_bh == 0 || dest_bi->bi_bh == 0,
631 	       "vs-10260: mode==%d, source (%p) or dest (%p) buffer is initialized incorrectly",
632 	       shift_mode, src_bi->bi_bh, dest_bi->bi_bh);
633 }
634 
635 /* copy mov_num items and mov_bytes of the (mov_num-1)th item to
636    neighbor. Delete them from source */
637 int leaf_move_items(int shift_mode, struct tree_balance *tb, int mov_num,
638 		    int mov_bytes, struct buffer_head *Snew)
639 {
640 	int ret_value;
641 	struct buffer_info dest_bi, src_bi;
642 	int first_last;
643 
644 	leaf_define_dest_src_infos(shift_mode, tb, &dest_bi, &src_bi,
645 				   &first_last, Snew);
646 
647 	ret_value =
648 	    leaf_copy_items(&dest_bi, src_bi.bi_bh, first_last, mov_num,
649 			    mov_bytes);
650 
651 	leaf_delete_items(&src_bi, first_last,
652 			  (first_last ==
653 			   FIRST_TO_LAST) ? 0 : (B_NR_ITEMS(src_bi.bi_bh) -
654 						 mov_num), mov_num, mov_bytes);
655 
656 	return ret_value;
657 }
658 
659 /* Shift shift_num items (and shift_bytes of last shifted item if shift_bytes != -1)
660    from S[0] to L[0] and replace the delimiting key */
661 int leaf_shift_left(struct tree_balance *tb, int shift_num, int shift_bytes)
662 {
663 	struct buffer_head *S0 = PATH_PLAST_BUFFER(tb->tb_path);
664 	int i;
665 
666 	/* move shift_num (and shift_bytes bytes) items from S[0] to left neighbor L[0] */
667 	i = leaf_move_items(LEAF_FROM_S_TO_L, tb, shift_num, shift_bytes, NULL);
668 
669 	if (shift_num) {
670 		if (B_NR_ITEMS(S0) == 0) {	/* number of items in S[0] == 0 */
671 
672 			RFALSE(shift_bytes != -1,
673 			       "vs-10270: S0 is empty now, but shift_bytes != -1 (%d)",
674 			       shift_bytes);
675 #ifdef CONFIG_REISERFS_CHECK
676 			if (tb->tb_mode == M_PASTE || tb->tb_mode == M_INSERT) {
677 				print_cur_tb("vs-10275");
678 				reiserfs_panic(tb->tb_sb,
679 					       "vs-10275: leaf_shift_left: balance condition corrupted (%c)",
680 					       tb->tb_mode);
681 			}
682 #endif
683 
684 			if (PATH_H_POSITION(tb->tb_path, 1) == 0)
685 				replace_key(tb, tb->CFL[0], tb->lkey[0],
686 					    PATH_H_PPARENT(tb->tb_path, 0), 0);
687 
688 		} else {
689 			/* replace lkey in CFL[0] by 0-th key from S[0]; */
690 			replace_key(tb, tb->CFL[0], tb->lkey[0], S0, 0);
691 
692 			RFALSE((shift_bytes != -1 &&
693 				!(is_direntry_le_ih(B_N_PITEM_HEAD(S0, 0))
694 				  && !I_ENTRY_COUNT(B_N_PITEM_HEAD(S0, 0)))) &&
695 			       (!op_is_left_mergeable
696 				(B_N_PKEY(S0, 0), S0->b_size)),
697 			       "vs-10280: item must be mergeable");
698 		}
699 	}
700 
701 	return i;
702 }
703 
704 /* CLEANING STOPPED HERE */
705 
706 /* Shift shift_num (shift_bytes) items from S[0] to the right neighbor, and replace the delimiting key */
707 int leaf_shift_right(struct tree_balance *tb, int shift_num, int shift_bytes)
708 {
709 	//  struct buffer_head * S0 = PATH_PLAST_BUFFER (tb->tb_path);
710 	int ret_value;
711 
712 	/* move shift_num (and shift_bytes) items from S[0] to right neighbor R[0] */
713 	ret_value =
714 	    leaf_move_items(LEAF_FROM_S_TO_R, tb, shift_num, shift_bytes, NULL);
715 
716 	/* replace rkey in CFR[0] by the 0-th key from R[0] */
717 	if (shift_num) {
718 		replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
719 
720 	}
721 
722 	return ret_value;
723 }
724 
725 static void leaf_delete_items_entirely(struct buffer_info *bi,
726 				       int first, int del_num);
727 /*  If del_bytes == -1, starting from position 'first' delete del_num items in whole in buffer CUR.
728     If not.
729     If last_first == 0. Starting from position 'first' delete del_num-1 items in whole. Delete part of body of
730     the first item. Part defined by del_bytes. Don't delete first item header
731     If last_first == 1. Starting from position 'first+1' delete del_num-1 items in whole. Delete part of body of
732     the last item . Part defined by del_bytes. Don't delete last item header.
733 */
734 void leaf_delete_items(struct buffer_info *cur_bi, int last_first,
735 		       int first, int del_num, int del_bytes)
736 {
737 	struct buffer_head *bh;
738 	int item_amount = B_NR_ITEMS(bh = cur_bi->bi_bh);
739 
740 	RFALSE(!bh, "10155: bh is not defined");
741 	RFALSE(del_num < 0, "10160: del_num can not be < 0. del_num==%d",
742 	       del_num);
743 	RFALSE(first < 0
744 	       || first + del_num > item_amount,
745 	       "10165: invalid number of first item to be deleted (%d) or "
746 	       "no so much items (%d) to delete (only %d)", first,
747 	       first + del_num, item_amount);
748 
749 	if (del_num == 0)
750 		return;
751 
752 	if (first == 0 && del_num == item_amount && del_bytes == -1) {
753 		make_empty_node(cur_bi);
754 		do_balance_mark_leaf_dirty(cur_bi->tb, bh, 0);
755 		return;
756 	}
757 
758 	if (del_bytes == -1)
759 		/* delete del_num items beginning from item in position first */
760 		leaf_delete_items_entirely(cur_bi, first, del_num);
761 	else {
762 		if (last_first == FIRST_TO_LAST) {
763 			/* delete del_num-1 items beginning from item in position first  */
764 			leaf_delete_items_entirely(cur_bi, first, del_num - 1);
765 
766 			/* delete the part of the first item of the bh
767 			   do not delete item header
768 			 */
769 			leaf_cut_from_buffer(cur_bi, 0, 0, del_bytes);
770 		} else {
771 			struct item_head *ih;
772 			int len;
773 
774 			/* delete del_num-1 items beginning from item in position first+1  */
775 			leaf_delete_items_entirely(cur_bi, first + 1,
776 						   del_num - 1);
777 
778 			if (is_direntry_le_ih
779 			    (ih = B_N_PITEM_HEAD(bh, B_NR_ITEMS(bh) - 1)))
780 				/* the last item is directory  */
781 				/* len = numbers of directory entries in this item */
782 				len = ih_entry_count(ih);
783 			else
784 				/* len = body len of item */
785 				len = ih_item_len(ih);
786 
787 			/* delete the part of the last item of the bh
788 			   do not delete item header
789 			 */
790 			leaf_cut_from_buffer(cur_bi, B_NR_ITEMS(bh) - 1,
791 					     len - del_bytes, del_bytes);
792 		}
793 	}
794 }
795 
796 /* insert item into the leaf node in position before */
797 void leaf_insert_into_buf(struct buffer_info *bi, int before,
798 			  struct item_head *inserted_item_ih,
799 			  const char *inserted_item_body, int zeros_number)
800 {
801 	struct buffer_head *bh = bi->bi_bh;
802 	int nr, free_space;
803 	struct block_head *blkh;
804 	struct item_head *ih;
805 	int i;
806 	int last_loc, unmoved_loc;
807 	char *to;
808 
809 	blkh = B_BLK_HEAD(bh);
810 	nr = blkh_nr_item(blkh);
811 	free_space = blkh_free_space(blkh);
812 
813 	/* check free space */
814 	RFALSE(free_space < ih_item_len(inserted_item_ih) + IH_SIZE,
815 	       "vs-10170: not enough free space in block %z, new item %h",
816 	       bh, inserted_item_ih);
817 	RFALSE(zeros_number > ih_item_len(inserted_item_ih),
818 	       "vs-10172: zero number == %d, item length == %d",
819 	       zeros_number, ih_item_len(inserted_item_ih));
820 
821 	/* get item new item must be inserted before */
822 	ih = B_N_PITEM_HEAD(bh, before);
823 
824 	/* prepare space for the body of new item */
825 	last_loc = nr ? ih_location(&(ih[nr - before - 1])) : bh->b_size;
826 	unmoved_loc = before ? ih_location(ih - 1) : bh->b_size;
827 
828 	memmove(bh->b_data + last_loc - ih_item_len(inserted_item_ih),
829 		bh->b_data + last_loc, unmoved_loc - last_loc);
830 
831 	to = bh->b_data + unmoved_loc - ih_item_len(inserted_item_ih);
832 	memset(to, 0, zeros_number);
833 	to += zeros_number;
834 
835 	/* copy body to prepared space */
836 	if (inserted_item_body)
837 		memmove(to, inserted_item_body,
838 			ih_item_len(inserted_item_ih) - zeros_number);
839 	else
840 		memset(to, '\0', ih_item_len(inserted_item_ih) - zeros_number);
841 
842 	/* insert item header */
843 	memmove(ih + 1, ih, IH_SIZE * (nr - before));
844 	memmove(ih, inserted_item_ih, IH_SIZE);
845 
846 	/* change locations */
847 	for (i = before; i < nr + 1; i++) {
848 		unmoved_loc -= ih_item_len(&(ih[i - before]));
849 		put_ih_location(&(ih[i - before]), unmoved_loc);
850 	}
851 
852 	/* sizes, free space, item number */
853 	set_blkh_nr_item(blkh, blkh_nr_item(blkh) + 1);
854 	set_blkh_free_space(blkh,
855 			    free_space - (IH_SIZE +
856 					  ih_item_len(inserted_item_ih)));
857 	do_balance_mark_leaf_dirty(bi->tb, bh, 1);
858 
859 	if (bi->bi_parent) {
860 		struct disk_child *t_dc;
861 		t_dc = B_N_CHILD(bi->bi_parent, bi->bi_position);
862 		put_dc_size(t_dc,
863 			    dc_size(t_dc) + (IH_SIZE +
864 					     ih_item_len(inserted_item_ih)));
865 		do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
866 	}
867 }
868 
869 /* paste paste_size bytes to affected_item_num-th item.
870    When item is a directory, this only prepare space for new entries */
871 void leaf_paste_in_buffer(struct buffer_info *bi, int affected_item_num,
872 			  int pos_in_item, int paste_size,
873 			  const char *body, int zeros_number)
874 {
875 	struct buffer_head *bh = bi->bi_bh;
876 	int nr, free_space;
877 	struct block_head *blkh;
878 	struct item_head *ih;
879 	int i;
880 	int last_loc, unmoved_loc;
881 
882 	blkh = B_BLK_HEAD(bh);
883 	nr = blkh_nr_item(blkh);
884 	free_space = blkh_free_space(blkh);
885 
886 	/* check free space */
887 	RFALSE(free_space < paste_size,
888 	       "vs-10175: not enough free space: needed %d, available %d",
889 	       paste_size, free_space);
890 
891 #ifdef CONFIG_REISERFS_CHECK
892 	if (zeros_number > paste_size) {
893 		print_cur_tb("10177");
894 		reiserfs_panic(NULL,
895 			       "vs-10177: leaf_paste_in_buffer: ero number == %d, paste_size == %d",
896 			       zeros_number, paste_size);
897 	}
898 #endif				/* CONFIG_REISERFS_CHECK */
899 
900 	/* item to be appended */
901 	ih = B_N_PITEM_HEAD(bh, affected_item_num);
902 
903 	last_loc = ih_location(&(ih[nr - affected_item_num - 1]));
904 	unmoved_loc = affected_item_num ? ih_location(ih - 1) : bh->b_size;
905 
906 	/* prepare space */
907 	memmove(bh->b_data + last_loc - paste_size, bh->b_data + last_loc,
908 		unmoved_loc - last_loc);
909 
910 	/* change locations */
911 	for (i = affected_item_num; i < nr; i++)
912 		put_ih_location(&(ih[i - affected_item_num]),
913 				ih_location(&(ih[i - affected_item_num])) -
914 				paste_size);
915 
916 	if (body) {
917 		if (!is_direntry_le_ih(ih)) {
918 			if (!pos_in_item) {
919 				/* shift data to right */
920 				memmove(bh->b_data + ih_location(ih) +
921 					paste_size,
922 					bh->b_data + ih_location(ih),
923 					ih_item_len(ih));
924 				/* paste data in the head of item */
925 				memset(bh->b_data + ih_location(ih), 0,
926 				       zeros_number);
927 				memcpy(bh->b_data + ih_location(ih) +
928 				       zeros_number, body,
929 				       paste_size - zeros_number);
930 			} else {
931 				memset(bh->b_data + unmoved_loc - paste_size, 0,
932 				       zeros_number);
933 				memcpy(bh->b_data + unmoved_loc - paste_size +
934 				       zeros_number, body,
935 				       paste_size - zeros_number);
936 			}
937 		}
938 	} else
939 		memset(bh->b_data + unmoved_loc - paste_size, '\0', paste_size);
940 
941 	put_ih_item_len(ih, ih_item_len(ih) + paste_size);
942 
943 	/* change free space */
944 	set_blkh_free_space(blkh, free_space - paste_size);
945 
946 	do_balance_mark_leaf_dirty(bi->tb, bh, 0);
947 
948 	if (bi->bi_parent) {
949 		struct disk_child *t_dc =
950 		    B_N_CHILD(bi->bi_parent, bi->bi_position);
951 		put_dc_size(t_dc, dc_size(t_dc) + paste_size);
952 		do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
953 	}
954 }
955 
956 /* cuts DEL_COUNT entries beginning from FROM-th entry. Directory item
957    does not have free space, so it moves DEHs and remaining records as
958    necessary. Return value is size of removed part of directory item
959    in bytes. */
960 static int leaf_cut_entries(struct buffer_head *bh,
961 			    struct item_head *ih, int from, int del_count)
962 {
963 	char *item;
964 	struct reiserfs_de_head *deh;
965 	int prev_record_offset;	/* offset of record, that is (from-1)th */
966 	char *prev_record;	/* */
967 	int cut_records_len;	/* length of all removed records */
968 	int i;
969 
970 	/* make sure, that item is directory and there are enough entries to
971 	   remove */
972 	RFALSE(!is_direntry_le_ih(ih), "10180: item is not directory item");
973 	RFALSE(I_ENTRY_COUNT(ih) < from + del_count,
974 	       "10185: item contains not enough entries: entry_cout = %d, from = %d, to delete = %d",
975 	       I_ENTRY_COUNT(ih), from, del_count);
976 
977 	if (del_count == 0)
978 		return 0;
979 
980 	/* first byte of item */
981 	item = bh->b_data + ih_location(ih);
982 
983 	/* entry head array */
984 	deh = B_I_DEH(bh, ih);
985 
986 	/* first byte of remaining entries, those are BEFORE cut entries
987 	   (prev_record) and length of all removed records (cut_records_len) */
988 	prev_record_offset =
989 	    (from ? deh_location(&(deh[from - 1])) : ih_item_len(ih));
990 	cut_records_len = prev_record_offset /*from_record */  -
991 	    deh_location(&(deh[from + del_count - 1]));
992 	prev_record = item + prev_record_offset;
993 
994 	/* adjust locations of remaining entries */
995 	for (i = I_ENTRY_COUNT(ih) - 1; i > from + del_count - 1; i--)
996 		put_deh_location(&(deh[i]),
997 				 deh_location(&deh[i]) -
998 				 (DEH_SIZE * del_count));
999 
1000 	for (i = 0; i < from; i++)
1001 		put_deh_location(&(deh[i]),
1002 				 deh_location(&deh[i]) - (DEH_SIZE * del_count +
1003 							  cut_records_len));
1004 
1005 	put_ih_entry_count(ih, ih_entry_count(ih) - del_count);
1006 
1007 	/* shift entry head array and entries those are AFTER removed entries */
1008 	memmove((char *)(deh + from),
1009 		deh + from + del_count,
1010 		prev_record - cut_records_len - (char *)(deh + from +
1011 							 del_count));
1012 
1013 	/* shift records, those are BEFORE removed entries */
1014 	memmove(prev_record - cut_records_len - DEH_SIZE * del_count,
1015 		prev_record, item + ih_item_len(ih) - prev_record);
1016 
1017 	return DEH_SIZE * del_count + cut_records_len;
1018 }
1019 
1020 /*  when cut item is part of regular file
1021         pos_in_item - first byte that must be cut
1022         cut_size - number of bytes to be cut beginning from pos_in_item
1023 
1024    when cut item is part of directory
1025         pos_in_item - number of first deleted entry
1026         cut_size - count of deleted entries
1027     */
1028 void leaf_cut_from_buffer(struct buffer_info *bi, int cut_item_num,
1029 			  int pos_in_item, int cut_size)
1030 {
1031 	int nr;
1032 	struct buffer_head *bh = bi->bi_bh;
1033 	struct block_head *blkh;
1034 	struct item_head *ih;
1035 	int last_loc, unmoved_loc;
1036 	int i;
1037 
1038 	blkh = B_BLK_HEAD(bh);
1039 	nr = blkh_nr_item(blkh);
1040 
1041 	/* item head of truncated item */
1042 	ih = B_N_PITEM_HEAD(bh, cut_item_num);
1043 
1044 	if (is_direntry_le_ih(ih)) {
1045 		/* first cut entry () */
1046 		cut_size = leaf_cut_entries(bh, ih, pos_in_item, cut_size);
1047 		if (pos_in_item == 0) {
1048 			/* change key */
1049 			RFALSE(cut_item_num,
1050 			       "when 0-th enrty of item is cut, that item must be first in the node, not %d-th",
1051 			       cut_item_num);
1052 			/* change item key by key of first entry in the item */
1053 			set_le_ih_k_offset(ih, deh_offset(B_I_DEH(bh, ih)));
1054 			/*memcpy (&ih->ih_key.k_offset, &(B_I_DEH (bh, ih)->deh_offset), SHORT_KEY_SIZE); */
1055 		}
1056 	} else {
1057 		/* item is direct or indirect */
1058 		RFALSE(is_statdata_le_ih(ih), "10195: item is stat data");
1059 		RFALSE(pos_in_item && pos_in_item + cut_size != ih_item_len(ih),
1060 		       "10200: invalid offset (%lu) or trunc_size (%lu) or ih_item_len (%lu)",
1061 		       (long unsigned)pos_in_item, (long unsigned)cut_size,
1062 		       (long unsigned)ih_item_len(ih));
1063 
1064 		/* shift item body to left if cut is from the head of item */
1065 		if (pos_in_item == 0) {
1066 			memmove(bh->b_data + ih_location(ih),
1067 				bh->b_data + ih_location(ih) + cut_size,
1068 				ih_item_len(ih) - cut_size);
1069 
1070 			/* change key of item */
1071 			if (is_direct_le_ih(ih))
1072 				set_le_ih_k_offset(ih,
1073 						   le_ih_k_offset(ih) +
1074 						   cut_size);
1075 			else {
1076 				set_le_ih_k_offset(ih,
1077 						   le_ih_k_offset(ih) +
1078 						   (cut_size / UNFM_P_SIZE) *
1079 						   bh->b_size);
1080 				RFALSE(ih_item_len(ih) == cut_size
1081 				       && get_ih_free_space(ih),
1082 				       "10205: invalid ih_free_space (%h)", ih);
1083 			}
1084 		}
1085 	}
1086 
1087 	/* location of the last item */
1088 	last_loc = ih_location(&(ih[nr - cut_item_num - 1]));
1089 
1090 	/* location of the item, which is remaining at the same place */
1091 	unmoved_loc = cut_item_num ? ih_location(ih - 1) : bh->b_size;
1092 
1093 	/* shift */
1094 	memmove(bh->b_data + last_loc + cut_size, bh->b_data + last_loc,
1095 		unmoved_loc - last_loc - cut_size);
1096 
1097 	/* change item length */
1098 	put_ih_item_len(ih, ih_item_len(ih) - cut_size);
1099 
1100 	if (is_indirect_le_ih(ih)) {
1101 		if (pos_in_item)
1102 			set_ih_free_space(ih, 0);
1103 	}
1104 
1105 	/* change locations */
1106 	for (i = cut_item_num; i < nr; i++)
1107 		put_ih_location(&(ih[i - cut_item_num]),
1108 				ih_location(&ih[i - cut_item_num]) + cut_size);
1109 
1110 	/* size, free space */
1111 	set_blkh_free_space(blkh, blkh_free_space(blkh) + cut_size);
1112 
1113 	do_balance_mark_leaf_dirty(bi->tb, bh, 0);
1114 
1115 	if (bi->bi_parent) {
1116 		struct disk_child *t_dc;
1117 		t_dc = B_N_CHILD(bi->bi_parent, bi->bi_position);
1118 		put_dc_size(t_dc, dc_size(t_dc) - cut_size);
1119 		do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
1120 	}
1121 }
1122 
1123 /* delete del_num items from buffer starting from the first'th item */
1124 static void leaf_delete_items_entirely(struct buffer_info *bi,
1125 				       int first, int del_num)
1126 {
1127 	struct buffer_head *bh = bi->bi_bh;
1128 	int nr;
1129 	int i, j;
1130 	int last_loc, last_removed_loc;
1131 	struct block_head *blkh;
1132 	struct item_head *ih;
1133 
1134 	RFALSE(bh == NULL, "10210: buffer is 0");
1135 	RFALSE(del_num < 0, "10215: del_num less than 0 (%d)", del_num);
1136 
1137 	if (del_num == 0)
1138 		return;
1139 
1140 	blkh = B_BLK_HEAD(bh);
1141 	nr = blkh_nr_item(blkh);
1142 
1143 	RFALSE(first < 0 || first + del_num > nr,
1144 	       "10220: first=%d, number=%d, there is %d items", first, del_num,
1145 	       nr);
1146 
1147 	if (first == 0 && del_num == nr) {
1148 		/* this does not work */
1149 		make_empty_node(bi);
1150 
1151 		do_balance_mark_leaf_dirty(bi->tb, bh, 0);
1152 		return;
1153 	}
1154 
1155 	ih = B_N_PITEM_HEAD(bh, first);
1156 
1157 	/* location of unmovable item */
1158 	j = (first == 0) ? bh->b_size : ih_location(ih - 1);
1159 
1160 	/* delete items */
1161 	last_loc = ih_location(&(ih[nr - 1 - first]));
1162 	last_removed_loc = ih_location(&(ih[del_num - 1]));
1163 
1164 	memmove(bh->b_data + last_loc + j - last_removed_loc,
1165 		bh->b_data + last_loc, last_removed_loc - last_loc);
1166 
1167 	/* delete item headers */
1168 	memmove(ih, ih + del_num, (nr - first - del_num) * IH_SIZE);
1169 
1170 	/* change item location */
1171 	for (i = first; i < nr - del_num; i++)
1172 		put_ih_location(&(ih[i - first]),
1173 				ih_location(&(ih[i - first])) + (j -
1174 								 last_removed_loc));
1175 
1176 	/* sizes, item number */
1177 	set_blkh_nr_item(blkh, blkh_nr_item(blkh) - del_num);
1178 	set_blkh_free_space(blkh,
1179 			    blkh_free_space(blkh) + (j - last_removed_loc +
1180 						     IH_SIZE * del_num));
1181 
1182 	do_balance_mark_leaf_dirty(bi->tb, bh, 0);
1183 
1184 	if (bi->bi_parent) {
1185 		struct disk_child *t_dc =
1186 		    B_N_CHILD(bi->bi_parent, bi->bi_position);
1187 		put_dc_size(t_dc,
1188 			    dc_size(t_dc) - (j - last_removed_loc +
1189 					     IH_SIZE * del_num));
1190 		do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
1191 	}
1192 }
1193 
1194 /* paste new_entry_count entries (new_dehs, records) into position before to item_num-th item */
1195 void leaf_paste_entries(struct buffer_head *bh,
1196 			int item_num,
1197 			int before,
1198 			int new_entry_count,
1199 			struct reiserfs_de_head *new_dehs,
1200 			const char *records, int paste_size)
1201 {
1202 	struct item_head *ih;
1203 	char *item;
1204 	struct reiserfs_de_head *deh;
1205 	char *insert_point;
1206 	int i, old_entry_num;
1207 
1208 	if (new_entry_count == 0)
1209 		return;
1210 
1211 	ih = B_N_PITEM_HEAD(bh, item_num);
1212 
1213 	/* make sure, that item is directory, and there are enough records in it */
1214 	RFALSE(!is_direntry_le_ih(ih), "10225: item is not directory item");
1215 	RFALSE(I_ENTRY_COUNT(ih) < before,
1216 	       "10230: there are no entry we paste entries before. entry_count = %d, before = %d",
1217 	       I_ENTRY_COUNT(ih), before);
1218 
1219 	/* first byte of dest item */
1220 	item = bh->b_data + ih_location(ih);
1221 
1222 	/* entry head array */
1223 	deh = B_I_DEH(bh, ih);
1224 
1225 	/* new records will be pasted at this point */
1226 	insert_point =
1227 	    item +
1228 	    (before ? deh_location(&(deh[before - 1]))
1229 	     : (ih_item_len(ih) - paste_size));
1230 
1231 	/* adjust locations of records that will be AFTER new records */
1232 	for (i = I_ENTRY_COUNT(ih) - 1; i >= before; i--)
1233 		put_deh_location(&(deh[i]),
1234 				 deh_location(&(deh[i])) +
1235 				 (DEH_SIZE * new_entry_count));
1236 
1237 	/* adjust locations of records that will be BEFORE new records */
1238 	for (i = 0; i < before; i++)
1239 		put_deh_location(&(deh[i]),
1240 				 deh_location(&(deh[i])) + paste_size);
1241 
1242 	old_entry_num = I_ENTRY_COUNT(ih);
1243 	put_ih_entry_count(ih, ih_entry_count(ih) + new_entry_count);
1244 
1245 	/* prepare space for pasted records */
1246 	memmove(insert_point + paste_size, insert_point,
1247 		item + (ih_item_len(ih) - paste_size) - insert_point);
1248 
1249 	/* copy new records */
1250 	memcpy(insert_point + DEH_SIZE * new_entry_count, records,
1251 	       paste_size - DEH_SIZE * new_entry_count);
1252 
1253 	/* prepare space for new entry heads */
1254 	deh += before;
1255 	memmove((char *)(deh + new_entry_count), deh,
1256 		insert_point - (char *)deh);
1257 
1258 	/* copy new entry heads */
1259 	deh = (struct reiserfs_de_head *)((char *)deh);
1260 	memcpy(deh, new_dehs, DEH_SIZE * new_entry_count);
1261 
1262 	/* set locations of new records */
1263 	for (i = 0; i < new_entry_count; i++) {
1264 		put_deh_location(&(deh[i]),
1265 				 deh_location(&(deh[i])) +
1266 				 (-deh_location
1267 				  (&(new_dehs[new_entry_count - 1])) +
1268 				  insert_point + DEH_SIZE * new_entry_count -
1269 				  item));
1270 	}
1271 
1272 	/* change item key if necessary (when we paste before 0-th entry */
1273 	if (!before) {
1274 		set_le_ih_k_offset(ih, deh_offset(new_dehs));
1275 /*      memcpy (&ih->ih_key.k_offset,
1276 		       &new_dehs->deh_offset, SHORT_KEY_SIZE);*/
1277 	}
1278 #ifdef CONFIG_REISERFS_CHECK
1279 	{
1280 		int prev, next;
1281 		/* check record locations */
1282 		deh = B_I_DEH(bh, ih);
1283 		for (i = 0; i < I_ENTRY_COUNT(ih); i++) {
1284 			next =
1285 			    (i <
1286 			     I_ENTRY_COUNT(ih) -
1287 			     1) ? deh_location(&(deh[i + 1])) : 0;
1288 			prev = (i != 0) ? deh_location(&(deh[i - 1])) : 0;
1289 
1290 			if (prev && prev <= deh_location(&(deh[i])))
1291 				reiserfs_warning(NULL,
1292 						 "vs-10240: leaf_paste_entries: directory item (%h) corrupted (prev %a, cur(%d) %a)",
1293 						 ih, deh + i - 1, i, deh + i);
1294 			if (next && next >= deh_location(&(deh[i])))
1295 				reiserfs_warning(NULL,
1296 						 "vs-10250: leaf_paste_entries: directory item (%h) corrupted (cur(%d) %a, next %a)",
1297 						 ih, i, deh + i, deh + i + 1);
1298 		}
1299 	}
1300 #endif
1301 
1302 }
1303