xref: /linux/fs/reiserfs/do_balan.c (revision a3a4a816b4b194c45d0217e8b9e08b2639802cda)
1 /*
2  * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3  */
4 
5 /*
6  * Now we have all buffers that must be used in balancing of the tree
7  * Further calculations can not cause schedule(), and thus the buffer
8  * tree will be stable until the balancing will be finished
9  * balance the tree according to the analysis made before,
10  * and using buffers obtained after all above.
11  */
12 
13 #include <linux/uaccess.h>
14 #include <linux/time.h>
15 #include "reiserfs.h"
16 #include <linux/buffer_head.h>
17 #include <linux/kernel.h>
18 
19 static inline void buffer_info_init_left(struct tree_balance *tb,
20                                          struct buffer_info *bi)
21 {
22 	bi->tb          = tb;
23 	bi->bi_bh       = tb->L[0];
24 	bi->bi_parent   = tb->FL[0];
25 	bi->bi_position = get_left_neighbor_position(tb, 0);
26 }
27 
28 static inline void buffer_info_init_right(struct tree_balance *tb,
29                                           struct buffer_info *bi)
30 {
31 	bi->tb          = tb;
32 	bi->bi_bh       = tb->R[0];
33 	bi->bi_parent   = tb->FR[0];
34 	bi->bi_position = get_right_neighbor_position(tb, 0);
35 }
36 
37 static inline void buffer_info_init_tbS0(struct tree_balance *tb,
38                                          struct buffer_info *bi)
39 {
40 	bi->tb          = tb;
41 	bi->bi_bh        = PATH_PLAST_BUFFER(tb->tb_path);
42 	bi->bi_parent   = PATH_H_PPARENT(tb->tb_path, 0);
43 	bi->bi_position = PATH_H_POSITION(tb->tb_path, 1);
44 }
45 
46 static inline void buffer_info_init_bh(struct tree_balance *tb,
47                                        struct buffer_info *bi,
48                                        struct buffer_head *bh)
49 {
50 	bi->tb          = tb;
51 	bi->bi_bh       = bh;
52 	bi->bi_parent   = NULL;
53 	bi->bi_position = 0;
54 }
55 
56 inline void do_balance_mark_leaf_dirty(struct tree_balance *tb,
57 				       struct buffer_head *bh, int flag)
58 {
59 	journal_mark_dirty(tb->transaction_handle, bh);
60 }
61 
62 #define do_balance_mark_internal_dirty do_balance_mark_leaf_dirty
63 #define do_balance_mark_sb_dirty do_balance_mark_leaf_dirty
64 
65 /*
66  * summary:
67  *  if deleting something ( tb->insert_size[0] < 0 )
68  *    return(balance_leaf_when_delete()); (flag d handled here)
69  *  else
70  *    if lnum is larger than 0 we put items into the left node
71  *    if rnum is larger than 0 we put items into the right node
72  *    if snum1 is larger than 0 we put items into the new node s1
73  *    if snum2 is larger than 0 we put items into the new node s2
74  * Note that all *num* count new items being created.
75  */
76 
77 static void balance_leaf_when_delete_del(struct tree_balance *tb)
78 {
79 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
80 	int item_pos = PATH_LAST_POSITION(tb->tb_path);
81 	struct buffer_info bi;
82 #ifdef CONFIG_REISERFS_CHECK
83 	struct item_head *ih = item_head(tbS0, item_pos);
84 #endif
85 
86 	RFALSE(ih_item_len(ih) + IH_SIZE != -tb->insert_size[0],
87 	       "vs-12013: mode Delete, insert size %d, ih to be deleted %h",
88 	       -tb->insert_size[0], ih);
89 
90 	buffer_info_init_tbS0(tb, &bi);
91 	leaf_delete_items(&bi, 0, item_pos, 1, -1);
92 
93 	if (!item_pos && tb->CFL[0]) {
94 		if (B_NR_ITEMS(tbS0)) {
95 			replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0, 0);
96 		} else {
97 			if (!PATH_H_POSITION(tb->tb_path, 1))
98 				replace_key(tb, tb->CFL[0], tb->lkey[0],
99 					    PATH_H_PPARENT(tb->tb_path, 0), 0);
100 		}
101 	}
102 
103 	RFALSE(!item_pos && !tb->CFL[0],
104 	       "PAP-12020: tb->CFL[0]==%p, tb->L[0]==%p", tb->CFL[0],
105 	       tb->L[0]);
106 }
107 
108 /* cut item in S[0] */
109 static void balance_leaf_when_delete_cut(struct tree_balance *tb)
110 {
111 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
112 	int item_pos = PATH_LAST_POSITION(tb->tb_path);
113 	struct item_head *ih = item_head(tbS0, item_pos);
114 	int pos_in_item = tb->tb_path->pos_in_item;
115 	struct buffer_info bi;
116 	buffer_info_init_tbS0(tb, &bi);
117 
118 	if (is_direntry_le_ih(ih)) {
119 		/*
120 		 * UFS unlink semantics are such that you can only
121 		 * delete one directory entry at a time.
122 		 *
123 		 * when we cut a directory tb->insert_size[0] means
124 		 * number of entries to be cut (always 1)
125 		 */
126 		tb->insert_size[0] = -1;
127 		leaf_cut_from_buffer(&bi, item_pos, pos_in_item,
128 				     -tb->insert_size[0]);
129 
130 		RFALSE(!item_pos && !pos_in_item && !tb->CFL[0],
131 		       "PAP-12030: can not change delimiting key. CFL[0]=%p",
132 		       tb->CFL[0]);
133 
134 		if (!item_pos && !pos_in_item && tb->CFL[0])
135 			replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0, 0);
136 	} else {
137 		leaf_cut_from_buffer(&bi, item_pos, pos_in_item,
138 				     -tb->insert_size[0]);
139 
140 		RFALSE(!ih_item_len(ih),
141 		       "PAP-12035: cut must leave non-zero dynamic "
142 		       "length of item");
143 	}
144 }
145 
146 static int balance_leaf_when_delete_left(struct tree_balance *tb)
147 {
148 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
149 	int n = B_NR_ITEMS(tbS0);
150 
151 	/* L[0] must be joined with S[0] */
152 	if (tb->lnum[0] == -1) {
153 		/* R[0] must be also joined with S[0] */
154 		if (tb->rnum[0] == -1) {
155 			if (tb->FR[0] == PATH_H_PPARENT(tb->tb_path, 0)) {
156 				/*
157 				 * all contents of all the
158 				 * 3 buffers will be in L[0]
159 				 */
160 				if (PATH_H_POSITION(tb->tb_path, 1) == 0 &&
161 				    1 < B_NR_ITEMS(tb->FR[0]))
162 					replace_key(tb, tb->CFL[0],
163 						    tb->lkey[0], tb->FR[0], 1);
164 
165 				leaf_move_items(LEAF_FROM_S_TO_L, tb, n, -1,
166 						NULL);
167 				leaf_move_items(LEAF_FROM_R_TO_L, tb,
168 						B_NR_ITEMS(tb->R[0]), -1,
169 						NULL);
170 
171 				reiserfs_invalidate_buffer(tb, tbS0);
172 				reiserfs_invalidate_buffer(tb, tb->R[0]);
173 
174 				return 0;
175 			}
176 
177 			/* all contents of all the 3 buffers will be in R[0] */
178 			leaf_move_items(LEAF_FROM_S_TO_R, tb, n, -1, NULL);
179 			leaf_move_items(LEAF_FROM_L_TO_R, tb,
180 					B_NR_ITEMS(tb->L[0]), -1, NULL);
181 
182 			/* right_delimiting_key is correct in R[0] */
183 			replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
184 
185 			reiserfs_invalidate_buffer(tb, tbS0);
186 			reiserfs_invalidate_buffer(tb, tb->L[0]);
187 
188 			return -1;
189 		}
190 
191 		RFALSE(tb->rnum[0] != 0,
192 		       "PAP-12045: rnum must be 0 (%d)", tb->rnum[0]);
193 		/* all contents of L[0] and S[0] will be in L[0] */
194 		leaf_shift_left(tb, n, -1);
195 
196 		reiserfs_invalidate_buffer(tb, tbS0);
197 
198 		return 0;
199 	}
200 
201 	/*
202 	 * a part of contents of S[0] will be in L[0] and
203 	 * the rest part of S[0] will be in R[0]
204 	 */
205 
206 	RFALSE((tb->lnum[0] + tb->rnum[0] < n) ||
207 	       (tb->lnum[0] + tb->rnum[0] > n + 1),
208 	       "PAP-12050: rnum(%d) and lnum(%d) and item "
209 	       "number(%d) in S[0] are not consistent",
210 	       tb->rnum[0], tb->lnum[0], n);
211 	RFALSE((tb->lnum[0] + tb->rnum[0] == n) &&
212 	       (tb->lbytes != -1 || tb->rbytes != -1),
213 	       "PAP-12055: bad rbytes (%d)/lbytes (%d) "
214 	       "parameters when items are not split",
215 	       tb->rbytes, tb->lbytes);
216 	RFALSE((tb->lnum[0] + tb->rnum[0] == n + 1) &&
217 	       (tb->lbytes < 1 || tb->rbytes != -1),
218 	       "PAP-12060: bad rbytes (%d)/lbytes (%d) "
219 	       "parameters when items are split",
220 	       tb->rbytes, tb->lbytes);
221 
222 	leaf_shift_left(tb, tb->lnum[0], tb->lbytes);
223 	leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
224 
225 	reiserfs_invalidate_buffer(tb, tbS0);
226 
227 	return 0;
228 }
229 
230 /*
231  * Balance leaf node in case of delete or cut: insert_size[0] < 0
232  *
233  * lnum, rnum can have values >= -1
234  *	-1 means that the neighbor must be joined with S
235  *	 0 means that nothing should be done with the neighbor
236  *	>0 means to shift entirely or partly the specified number of items
237  *         to the neighbor
238  */
239 static int balance_leaf_when_delete(struct tree_balance *tb, int flag)
240 {
241 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
242 	int item_pos = PATH_LAST_POSITION(tb->tb_path);
243 	struct buffer_info bi;
244 	int n;
245 	struct item_head *ih;
246 
247 	RFALSE(tb->FR[0] && B_LEVEL(tb->FR[0]) != DISK_LEAF_NODE_LEVEL + 1,
248 	       "vs- 12000: level: wrong FR %z", tb->FR[0]);
249 	RFALSE(tb->blknum[0] > 1,
250 	       "PAP-12005: tb->blknum == %d, can not be > 1", tb->blknum[0]);
251 	RFALSE(!tb->blknum[0] && !PATH_H_PPARENT(tb->tb_path, 0),
252 	       "PAP-12010: tree can not be empty");
253 
254 	ih = item_head(tbS0, item_pos);
255 	buffer_info_init_tbS0(tb, &bi);
256 
257 	/* Delete or truncate the item */
258 
259 	BUG_ON(flag != M_DELETE && flag != M_CUT);
260 	if (flag == M_DELETE)
261 		balance_leaf_when_delete_del(tb);
262 	else /* M_CUT */
263 		balance_leaf_when_delete_cut(tb);
264 
265 
266 	/*
267 	 * the rule is that no shifting occurs unless by shifting
268 	 * a node can be freed
269 	 */
270 	n = B_NR_ITEMS(tbS0);
271 
272 
273 	/* L[0] takes part in balancing */
274 	if (tb->lnum[0])
275 		return balance_leaf_when_delete_left(tb);
276 
277 	if (tb->rnum[0] == -1) {
278 		/* all contents of R[0] and S[0] will be in R[0] */
279 		leaf_shift_right(tb, n, -1);
280 		reiserfs_invalidate_buffer(tb, tbS0);
281 		return 0;
282 	}
283 
284 	RFALSE(tb->rnum[0],
285 	       "PAP-12065: bad rnum parameter must be 0 (%d)", tb->rnum[0]);
286 	return 0;
287 }
288 
289 static unsigned int balance_leaf_insert_left(struct tree_balance *tb,
290 					     struct item_head *const ih,
291 					     const char * const body)
292 {
293 	int ret;
294 	struct buffer_info bi;
295 	int n = B_NR_ITEMS(tb->L[0]);
296 	unsigned body_shift_bytes = 0;
297 
298 	if (tb->item_pos == tb->lnum[0] - 1 && tb->lbytes != -1) {
299 		/* part of new item falls into L[0] */
300 		int new_item_len, shift;
301 		int version;
302 
303 		ret = leaf_shift_left(tb, tb->lnum[0] - 1, -1);
304 
305 		/* Calculate item length to insert to S[0] */
306 		new_item_len = ih_item_len(ih) - tb->lbytes;
307 
308 		/* Calculate and check item length to insert to L[0] */
309 		put_ih_item_len(ih, ih_item_len(ih) - new_item_len);
310 
311 		RFALSE(ih_item_len(ih) <= 0,
312 		       "PAP-12080: there is nothing to insert into L[0]: "
313 		       "ih_item_len=%d", ih_item_len(ih));
314 
315 		/* Insert new item into L[0] */
316 		buffer_info_init_left(tb, &bi);
317 		leaf_insert_into_buf(&bi, n + tb->item_pos - ret, ih, body,
318 			     min_t(int, tb->zeroes_num, ih_item_len(ih)));
319 
320 		version = ih_version(ih);
321 
322 		/*
323 		 * Calculate key component, item length and body to
324 		 * insert into S[0]
325 		 */
326 		shift = 0;
327 		if (is_indirect_le_ih(ih))
328 			shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT;
329 
330 		add_le_ih_k_offset(ih, tb->lbytes << shift);
331 
332 		put_ih_item_len(ih, new_item_len);
333 		if (tb->lbytes > tb->zeroes_num) {
334 			body_shift_bytes = tb->lbytes - tb->zeroes_num;
335 			tb->zeroes_num = 0;
336 		} else
337 			tb->zeroes_num -= tb->lbytes;
338 
339 		RFALSE(ih_item_len(ih) <= 0,
340 		       "PAP-12085: there is nothing to insert into S[0]: "
341 		       "ih_item_len=%d", ih_item_len(ih));
342 	} else {
343 		/* new item in whole falls into L[0] */
344 		/* Shift lnum[0]-1 items to L[0] */
345 		ret = leaf_shift_left(tb, tb->lnum[0] - 1, tb->lbytes);
346 
347 		/* Insert new item into L[0] */
348 		buffer_info_init_left(tb, &bi);
349 		leaf_insert_into_buf(&bi, n + tb->item_pos - ret, ih, body,
350 				     tb->zeroes_num);
351 		tb->insert_size[0] = 0;
352 		tb->zeroes_num = 0;
353 	}
354 	return body_shift_bytes;
355 }
356 
357 static void balance_leaf_paste_left_shift_dirent(struct tree_balance *tb,
358 						 struct item_head * const ih,
359 						 const char * const body)
360 {
361 	int n = B_NR_ITEMS(tb->L[0]);
362 	struct buffer_info bi;
363 
364 	RFALSE(tb->zeroes_num,
365 	       "PAP-12090: invalid parameter in case of a directory");
366 
367 	/* directory item */
368 	if (tb->lbytes > tb->pos_in_item) {
369 		/* new directory entry falls into L[0] */
370 		struct item_head *pasted;
371 		int ret, l_pos_in_item = tb->pos_in_item;
372 
373 		/*
374 		 * Shift lnum[0] - 1 items in whole.
375 		 * Shift lbytes - 1 entries from given directory item
376 		 */
377 		ret = leaf_shift_left(tb, tb->lnum[0], tb->lbytes - 1);
378 		if (ret && !tb->item_pos) {
379 			pasted = item_head(tb->L[0], B_NR_ITEMS(tb->L[0]) - 1);
380 			l_pos_in_item += ih_entry_count(pasted) -
381 					 (tb->lbytes - 1);
382 		}
383 
384 		/* Append given directory entry to directory item */
385 		buffer_info_init_left(tb, &bi);
386 		leaf_paste_in_buffer(&bi, n + tb->item_pos - ret,
387 				     l_pos_in_item, tb->insert_size[0],
388 				     body, tb->zeroes_num);
389 
390 		/*
391 		 * previous string prepared space for pasting new entry,
392 		 * following string pastes this entry
393 		 */
394 
395 		/*
396 		 * when we have merge directory item, pos_in_item
397 		 * has been changed too
398 		 */
399 
400 		/* paste new directory entry. 1 is entry number */
401 		leaf_paste_entries(&bi, n + tb->item_pos - ret,
402 				   l_pos_in_item, 1,
403 				   (struct reiserfs_de_head *) body,
404 				   body + DEH_SIZE, tb->insert_size[0]);
405 		tb->insert_size[0] = 0;
406 	} else {
407 		/* new directory item doesn't fall into L[0] */
408 		/*
409 		 * Shift lnum[0]-1 items in whole. Shift lbytes
410 		 * directory entries from directory item number lnum[0]
411 		 */
412 		leaf_shift_left(tb, tb->lnum[0], tb->lbytes);
413 	}
414 
415 	/* Calculate new position to append in item body */
416 	tb->pos_in_item -= tb->lbytes;
417 }
418 
419 static unsigned int balance_leaf_paste_left_shift(struct tree_balance *tb,
420 						  struct item_head * const ih,
421 						  const char * const body)
422 {
423 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
424 	int n = B_NR_ITEMS(tb->L[0]);
425 	struct buffer_info bi;
426 	int body_shift_bytes = 0;
427 
428 	if (is_direntry_le_ih(item_head(tbS0, tb->item_pos))) {
429 		balance_leaf_paste_left_shift_dirent(tb, ih, body);
430 		return 0;
431 	}
432 
433 	RFALSE(tb->lbytes <= 0,
434 	       "PAP-12095: there is nothing to shift to L[0]. "
435 	       "lbytes=%d", tb->lbytes);
436 	RFALSE(tb->pos_in_item != ih_item_len(item_head(tbS0, tb->item_pos)),
437 	       "PAP-12100: incorrect position to paste: "
438 	       "item_len=%d, pos_in_item=%d",
439 	       ih_item_len(item_head(tbS0, tb->item_pos)), tb->pos_in_item);
440 
441 	/* appended item will be in L[0] in whole */
442 	if (tb->lbytes >= tb->pos_in_item) {
443 		struct item_head *tbS0_pos_ih, *tbL0_ih;
444 		struct item_head *tbS0_0_ih;
445 		struct reiserfs_key *left_delim_key;
446 		int ret, l_n, version, temp_l;
447 
448 		tbS0_pos_ih = item_head(tbS0, tb->item_pos);
449 		tbS0_0_ih = item_head(tbS0, 0);
450 
451 		/*
452 		 * this bytes number must be appended
453 		 * to the last item of L[h]
454 		 */
455 		l_n = tb->lbytes - tb->pos_in_item;
456 
457 		/* Calculate new insert_size[0] */
458 		tb->insert_size[0] -= l_n;
459 
460 		RFALSE(tb->insert_size[0] <= 0,
461 		       "PAP-12105: there is nothing to paste into "
462 		       "L[0]. insert_size=%d", tb->insert_size[0]);
463 
464 		ret = leaf_shift_left(tb, tb->lnum[0],
465 				      ih_item_len(tbS0_pos_ih));
466 
467 		tbL0_ih = item_head(tb->L[0], n + tb->item_pos - ret);
468 
469 		/* Append to body of item in L[0] */
470 		buffer_info_init_left(tb, &bi);
471 		leaf_paste_in_buffer(&bi, n + tb->item_pos - ret,
472 				     ih_item_len(tbL0_ih), l_n, body,
473 				     min_t(int, l_n, tb->zeroes_num));
474 
475 		/*
476 		 * 0-th item in S0 can be only of DIRECT type
477 		 * when l_n != 0
478 		 */
479 		temp_l = l_n;
480 
481 		RFALSE(ih_item_len(tbS0_0_ih),
482 		       "PAP-12106: item length must be 0");
483 		RFALSE(comp_short_le_keys(&tbS0_0_ih->ih_key,
484 		       leaf_key(tb->L[0], n + tb->item_pos - ret)),
485 		       "PAP-12107: items must be of the same file");
486 
487 		if (is_indirect_le_ih(tbL0_ih)) {
488 			int shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT;
489 			temp_l = l_n << shift;
490 		}
491 		/* update key of first item in S0 */
492 		version = ih_version(tbS0_0_ih);
493 		add_le_key_k_offset(version, &tbS0_0_ih->ih_key, temp_l);
494 
495 		/* update left delimiting key */
496 		left_delim_key = internal_key(tb->CFL[0], tb->lkey[0]);
497 		add_le_key_k_offset(version, left_delim_key, temp_l);
498 
499 		/*
500 		 * Calculate new body, position in item and
501 		 * insert_size[0]
502 		 */
503 		if (l_n > tb->zeroes_num) {
504 			body_shift_bytes = l_n - tb->zeroes_num;
505 			tb->zeroes_num = 0;
506 		} else
507 			tb->zeroes_num -= l_n;
508 		tb->pos_in_item = 0;
509 
510 		RFALSE(comp_short_le_keys(&tbS0_0_ih->ih_key,
511 					  leaf_key(tb->L[0],
512 						 B_NR_ITEMS(tb->L[0]) - 1)) ||
513 		       !op_is_left_mergeable(leaf_key(tbS0, 0), tbS0->b_size) ||
514 		       !op_is_left_mergeable(left_delim_key, tbS0->b_size),
515 		       "PAP-12120: item must be merge-able with left "
516 		       "neighboring item");
517 	} else {
518 		/* only part of the appended item will be in L[0] */
519 
520 		/* Calculate position in item for append in S[0] */
521 		tb->pos_in_item -= tb->lbytes;
522 
523 		RFALSE(tb->pos_in_item <= 0,
524 		       "PAP-12125: no place for paste. pos_in_item=%d",
525 		       tb->pos_in_item);
526 
527 		/*
528 		 * Shift lnum[0] - 1 items in whole.
529 		 * Shift lbytes - 1 byte from item number lnum[0]
530 		 */
531 		leaf_shift_left(tb, tb->lnum[0], tb->lbytes);
532 	}
533 	return body_shift_bytes;
534 }
535 
536 
537 /* appended item will be in L[0] in whole */
538 static void balance_leaf_paste_left_whole(struct tree_balance *tb,
539 					  struct item_head * const ih,
540 					  const char * const body)
541 {
542 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
543 	int n = B_NR_ITEMS(tb->L[0]);
544 	struct buffer_info bi;
545 	struct item_head *pasted;
546 	int ret;
547 
548 	/* if we paste into first item of S[0] and it is left mergable */
549 	if (!tb->item_pos &&
550 	    op_is_left_mergeable(leaf_key(tbS0, 0), tbS0->b_size)) {
551 		/*
552 		 * then increment pos_in_item by the size of the
553 		 * last item in L[0]
554 		 */
555 		pasted = item_head(tb->L[0], n - 1);
556 		if (is_direntry_le_ih(pasted))
557 			tb->pos_in_item += ih_entry_count(pasted);
558 		else
559 			tb->pos_in_item += ih_item_len(pasted);
560 	}
561 
562 	/*
563 	 * Shift lnum[0] - 1 items in whole.
564 	 * Shift lbytes - 1 byte from item number lnum[0]
565 	 */
566 	ret = leaf_shift_left(tb, tb->lnum[0], tb->lbytes);
567 
568 	/* Append to body of item in L[0] */
569 	buffer_info_init_left(tb, &bi);
570 	leaf_paste_in_buffer(&bi, n + tb->item_pos - ret, tb->pos_in_item,
571 			     tb->insert_size[0], body, tb->zeroes_num);
572 
573 	/* if appended item is directory, paste entry */
574 	pasted = item_head(tb->L[0], n + tb->item_pos - ret);
575 	if (is_direntry_le_ih(pasted))
576 		leaf_paste_entries(&bi, n + tb->item_pos - ret,
577 				   tb->pos_in_item, 1,
578 				   (struct reiserfs_de_head *)body,
579 				   body + DEH_SIZE, tb->insert_size[0]);
580 
581 	/*
582 	 * if appended item is indirect item, put unformatted node
583 	 * into un list
584 	 */
585 	if (is_indirect_le_ih(pasted))
586 		set_ih_free_space(pasted, 0);
587 
588 	tb->insert_size[0] = 0;
589 	tb->zeroes_num = 0;
590 }
591 
592 static unsigned int balance_leaf_paste_left(struct tree_balance *tb,
593 					    struct item_head * const ih,
594 					    const char * const body)
595 {
596 	/* we must shift the part of the appended item */
597 	if (tb->item_pos == tb->lnum[0] - 1 && tb->lbytes != -1)
598 		return balance_leaf_paste_left_shift(tb, ih, body);
599 	else
600 		balance_leaf_paste_left_whole(tb, ih, body);
601 	return 0;
602 }
603 
604 /* Shift lnum[0] items from S[0] to the left neighbor L[0] */
605 static unsigned int balance_leaf_left(struct tree_balance *tb,
606 				      struct item_head * const ih,
607 				      const char * const body, int flag)
608 {
609 	if (tb->lnum[0] <= 0)
610 		return 0;
611 
612 	/* new item or it part falls to L[0], shift it too */
613 	if (tb->item_pos < tb->lnum[0]) {
614 		BUG_ON(flag != M_INSERT && flag != M_PASTE);
615 
616 		if (flag == M_INSERT)
617 			return balance_leaf_insert_left(tb, ih, body);
618 		else /* M_PASTE */
619 			return balance_leaf_paste_left(tb, ih, body);
620 	} else
621 		/* new item doesn't fall into L[0] */
622 		leaf_shift_left(tb, tb->lnum[0], tb->lbytes);
623 	return 0;
624 }
625 
626 
627 static void balance_leaf_insert_right(struct tree_balance *tb,
628 				      struct item_head * const ih,
629 				      const char * const body)
630 {
631 
632 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
633 	int n = B_NR_ITEMS(tbS0);
634 	struct buffer_info bi;
635 	int ret;
636 
637 	/* new item or part of it doesn't fall into R[0] */
638 	if (n - tb->rnum[0] >= tb->item_pos) {
639 		leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
640 		return;
641 	}
642 
643 	/* new item or its part falls to R[0] */
644 
645 	/* part of new item falls into R[0] */
646 	if (tb->item_pos == n - tb->rnum[0] + 1 && tb->rbytes != -1) {
647 		loff_t old_key_comp, old_len, r_zeroes_number;
648 		const char *r_body;
649 		int version, shift;
650 		loff_t offset;
651 
652 		leaf_shift_right(tb, tb->rnum[0] - 1, -1);
653 
654 		version = ih_version(ih);
655 
656 		/* Remember key component and item length */
657 		old_key_comp = le_ih_k_offset(ih);
658 		old_len = ih_item_len(ih);
659 
660 		/*
661 		 * Calculate key component and item length to insert
662 		 * into R[0]
663 		 */
664 		shift = 0;
665 		if (is_indirect_le_ih(ih))
666 			shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT;
667 		offset = le_ih_k_offset(ih) + ((old_len - tb->rbytes) << shift);
668 		set_le_ih_k_offset(ih, offset);
669 		put_ih_item_len(ih, tb->rbytes);
670 
671 		/* Insert part of the item into R[0] */
672 		buffer_info_init_right(tb, &bi);
673 		if ((old_len - tb->rbytes) > tb->zeroes_num) {
674 			r_zeroes_number = 0;
675 			r_body = body + (old_len - tb->rbytes) - tb->zeroes_num;
676 		} else {
677 			r_body = body;
678 			r_zeroes_number = tb->zeroes_num -
679 					  (old_len - tb->rbytes);
680 			tb->zeroes_num -= r_zeroes_number;
681 		}
682 
683 		leaf_insert_into_buf(&bi, 0, ih, r_body, r_zeroes_number);
684 
685 		/* Replace right delimiting key by first key in R[0] */
686 		replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
687 
688 		/*
689 		 * Calculate key component and item length to
690 		 * insert into S[0]
691 		 */
692 		set_le_ih_k_offset(ih, old_key_comp);
693 		put_ih_item_len(ih, old_len - tb->rbytes);
694 
695 		tb->insert_size[0] -= tb->rbytes;
696 
697 	} else {
698 		/* whole new item falls into R[0] */
699 
700 		/* Shift rnum[0]-1 items to R[0] */
701 		ret = leaf_shift_right(tb, tb->rnum[0] - 1, tb->rbytes);
702 
703 		/* Insert new item into R[0] */
704 		buffer_info_init_right(tb, &bi);
705 		leaf_insert_into_buf(&bi, tb->item_pos - n + tb->rnum[0] - 1,
706 				     ih, body, tb->zeroes_num);
707 
708 		if (tb->item_pos - n + tb->rnum[0] - 1 == 0)
709 			replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
710 
711 		tb->zeroes_num = tb->insert_size[0] = 0;
712 	}
713 }
714 
715 
716 static void balance_leaf_paste_right_shift_dirent(struct tree_balance *tb,
717 				     struct item_head * const ih,
718 				     const char * const body)
719 {
720 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
721 	struct buffer_info bi;
722 	int entry_count;
723 
724 	RFALSE(tb->zeroes_num,
725 	       "PAP-12145: invalid parameter in case of a directory");
726 	entry_count = ih_entry_count(item_head(tbS0, tb->item_pos));
727 
728 	/* new directory entry falls into R[0] */
729 	if (entry_count - tb->rbytes < tb->pos_in_item) {
730 		int paste_entry_position;
731 
732 		RFALSE(tb->rbytes - 1 >= entry_count || !tb->insert_size[0],
733 		       "PAP-12150: no enough of entries to shift to R[0]: "
734 		       "rbytes=%d, entry_count=%d", tb->rbytes, entry_count);
735 
736 		/*
737 		 * Shift rnum[0]-1 items in whole.
738 		 * Shift rbytes-1 directory entries from directory
739 		 * item number rnum[0]
740 		 */
741 		leaf_shift_right(tb, tb->rnum[0], tb->rbytes - 1);
742 
743 		/* Paste given directory entry to directory item */
744 		paste_entry_position = tb->pos_in_item - entry_count +
745 				       tb->rbytes - 1;
746 		buffer_info_init_right(tb, &bi);
747 		leaf_paste_in_buffer(&bi, 0, paste_entry_position,
748 				     tb->insert_size[0], body, tb->zeroes_num);
749 
750 		/* paste entry */
751 		leaf_paste_entries(&bi, 0, paste_entry_position, 1,
752 				   (struct reiserfs_de_head *) body,
753 				   body + DEH_SIZE, tb->insert_size[0]);
754 
755 		/* change delimiting keys */
756 		if (paste_entry_position == 0)
757 			replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
758 
759 		tb->insert_size[0] = 0;
760 		tb->pos_in_item++;
761 	} else {
762 		/* new directory entry doesn't fall into R[0] */
763 		leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
764 	}
765 }
766 
767 static void balance_leaf_paste_right_shift(struct tree_balance *tb,
768 				     struct item_head * const ih,
769 				     const char * const body)
770 {
771 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
772 	int n_shift, n_rem, r_zeroes_number, version;
773 	unsigned long temp_rem;
774 	const char *r_body;
775 	struct buffer_info bi;
776 
777 	/* we append to directory item */
778 	if (is_direntry_le_ih(item_head(tbS0, tb->item_pos))) {
779 		balance_leaf_paste_right_shift_dirent(tb, ih, body);
780 		return;
781 	}
782 
783 	/* regular object */
784 
785 	/*
786 	 * Calculate number of bytes which must be shifted
787 	 * from appended item
788 	 */
789 	n_shift = tb->rbytes - tb->insert_size[0];
790 	if (n_shift < 0)
791 		n_shift = 0;
792 
793 	RFALSE(tb->pos_in_item != ih_item_len(item_head(tbS0, tb->item_pos)),
794 	       "PAP-12155: invalid position to paste. ih_item_len=%d, "
795 	       "pos_in_item=%d", tb->pos_in_item,
796 	       ih_item_len(item_head(tbS0, tb->item_pos)));
797 
798 	leaf_shift_right(tb, tb->rnum[0], n_shift);
799 
800 	/*
801 	 * Calculate number of bytes which must remain in body
802 	 * after appending to R[0]
803 	 */
804 	n_rem = tb->insert_size[0] - tb->rbytes;
805 	if (n_rem < 0)
806 		n_rem = 0;
807 
808 	temp_rem = n_rem;
809 
810 	version = ih_version(item_head(tb->R[0], 0));
811 
812 	if (is_indirect_le_key(version, leaf_key(tb->R[0], 0))) {
813 		int shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT;
814 		temp_rem = n_rem << shift;
815 	}
816 
817 	add_le_key_k_offset(version, leaf_key(tb->R[0], 0), temp_rem);
818 	add_le_key_k_offset(version, internal_key(tb->CFR[0], tb->rkey[0]),
819 			    temp_rem);
820 
821 	do_balance_mark_internal_dirty(tb, tb->CFR[0], 0);
822 
823 	/* Append part of body into R[0] */
824 	buffer_info_init_right(tb, &bi);
825 	if (n_rem > tb->zeroes_num) {
826 		r_zeroes_number = 0;
827 		r_body = body + n_rem - tb->zeroes_num;
828 	} else {
829 		r_body = body;
830 		r_zeroes_number = tb->zeroes_num - n_rem;
831 		tb->zeroes_num -= r_zeroes_number;
832 	}
833 
834 	leaf_paste_in_buffer(&bi, 0, n_shift, tb->insert_size[0] - n_rem,
835 			     r_body, r_zeroes_number);
836 
837 	if (is_indirect_le_ih(item_head(tb->R[0], 0)))
838 		set_ih_free_space(item_head(tb->R[0], 0), 0);
839 
840 	tb->insert_size[0] = n_rem;
841 	if (!n_rem)
842 		tb->pos_in_item++;
843 }
844 
845 static void balance_leaf_paste_right_whole(struct tree_balance *tb,
846 				     struct item_head * const ih,
847 				     const char * const body)
848 {
849 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
850 	int n = B_NR_ITEMS(tbS0);
851 	struct item_head *pasted;
852 	struct buffer_info bi;
853 
854 							buffer_info_init_right(tb, &bi);
855 	leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
856 
857 	/* append item in R[0] */
858 	if (tb->pos_in_item >= 0) {
859 		buffer_info_init_right(tb, &bi);
860 		leaf_paste_in_buffer(&bi, tb->item_pos - n + tb->rnum[0],
861 				     tb->pos_in_item, tb->insert_size[0], body,
862 				     tb->zeroes_num);
863 	}
864 
865 	/* paste new entry, if item is directory item */
866 	pasted = item_head(tb->R[0], tb->item_pos - n + tb->rnum[0]);
867 	if (is_direntry_le_ih(pasted) && tb->pos_in_item >= 0) {
868 		leaf_paste_entries(&bi, tb->item_pos - n + tb->rnum[0],
869 				   tb->pos_in_item, 1,
870 				   (struct reiserfs_de_head *)body,
871 				   body + DEH_SIZE, tb->insert_size[0]);
872 
873 		if (!tb->pos_in_item) {
874 
875 			RFALSE(tb->item_pos - n + tb->rnum[0],
876 			       "PAP-12165: directory item must be first "
877 			       "item of node when pasting is in 0th position");
878 
879 			/* update delimiting keys */
880 			replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
881 		}
882 	}
883 
884 	if (is_indirect_le_ih(pasted))
885 		set_ih_free_space(pasted, 0);
886 	tb->zeroes_num = tb->insert_size[0] = 0;
887 }
888 
889 static void balance_leaf_paste_right(struct tree_balance *tb,
890 				     struct item_head * const ih,
891 				     const char * const body)
892 {
893 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
894 	int n = B_NR_ITEMS(tbS0);
895 
896 	/* new item doesn't fall into R[0] */
897 	if (n - tb->rnum[0] > tb->item_pos) {
898 		leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
899 		return;
900 	}
901 
902 	/* pasted item or part of it falls to R[0] */
903 
904 	if (tb->item_pos == n - tb->rnum[0] && tb->rbytes != -1)
905 		/* we must shift the part of the appended item */
906 		balance_leaf_paste_right_shift(tb, ih, body);
907 	else
908 		/* pasted item in whole falls into R[0] */
909 		balance_leaf_paste_right_whole(tb, ih, body);
910 }
911 
912 /* shift rnum[0] items from S[0] to the right neighbor R[0] */
913 static void balance_leaf_right(struct tree_balance *tb,
914 			       struct item_head * const ih,
915 			       const char * const body, int flag)
916 {
917 	if (tb->rnum[0] <= 0)
918 		return;
919 
920 	BUG_ON(flag != M_INSERT && flag != M_PASTE);
921 
922 	if (flag == M_INSERT)
923 		balance_leaf_insert_right(tb, ih, body);
924 	else /* M_PASTE */
925 		balance_leaf_paste_right(tb, ih, body);
926 }
927 
928 static void balance_leaf_new_nodes_insert(struct tree_balance *tb,
929 					  struct item_head * const ih,
930 					  const char * const body,
931 					  struct item_head *insert_key,
932 					  struct buffer_head **insert_ptr,
933 					  int i)
934 {
935 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
936 	int n = B_NR_ITEMS(tbS0);
937 	struct buffer_info bi;
938 	int shift;
939 
940 	/* new item or it part don't falls into S_new[i] */
941 	if (n - tb->snum[i] >= tb->item_pos) {
942 		leaf_move_items(LEAF_FROM_S_TO_SNEW, tb,
943 				tb->snum[i], tb->sbytes[i], tb->S_new[i]);
944 		return;
945 	}
946 
947 	/* new item or it's part falls to first new node S_new[i] */
948 
949 	/* part of new item falls into S_new[i] */
950 	if (tb->item_pos == n - tb->snum[i] + 1 && tb->sbytes[i] != -1) {
951 		int old_key_comp, old_len, r_zeroes_number;
952 		const char *r_body;
953 		int version;
954 
955 		/* Move snum[i]-1 items from S[0] to S_new[i] */
956 		leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i] - 1, -1,
957 				tb->S_new[i]);
958 
959 		/* Remember key component and item length */
960 		version = ih_version(ih);
961 		old_key_comp = le_ih_k_offset(ih);
962 		old_len = ih_item_len(ih);
963 
964 		/*
965 		 * Calculate key component and item length to insert
966 		 * into S_new[i]
967 		 */
968 		shift = 0;
969 		if (is_indirect_le_ih(ih))
970 			shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT;
971 		set_le_ih_k_offset(ih,
972 				   le_ih_k_offset(ih) +
973 				   ((old_len - tb->sbytes[i]) << shift));
974 
975 		put_ih_item_len(ih, tb->sbytes[i]);
976 
977 		/* Insert part of the item into S_new[i] before 0-th item */
978 		buffer_info_init_bh(tb, &bi, tb->S_new[i]);
979 
980 		if ((old_len - tb->sbytes[i]) > tb->zeroes_num) {
981 			r_zeroes_number = 0;
982 			r_body = body + (old_len - tb->sbytes[i]) -
983 					 tb->zeroes_num;
984 		} else {
985 			r_body = body;
986 			r_zeroes_number = tb->zeroes_num - (old_len -
987 					  tb->sbytes[i]);
988 			tb->zeroes_num -= r_zeroes_number;
989 		}
990 
991 		leaf_insert_into_buf(&bi, 0, ih, r_body, r_zeroes_number);
992 
993 		/*
994 		 * Calculate key component and item length to
995 		 * insert into S[i]
996 		 */
997 		set_le_ih_k_offset(ih, old_key_comp);
998 		put_ih_item_len(ih, old_len - tb->sbytes[i]);
999 		tb->insert_size[0] -= tb->sbytes[i];
1000 	} else {
1001 		/* whole new item falls into S_new[i] */
1002 
1003 		/*
1004 		 * Shift snum[0] - 1 items to S_new[i]
1005 		 * (sbytes[i] of split item)
1006 		 */
1007 		leaf_move_items(LEAF_FROM_S_TO_SNEW, tb,
1008 				tb->snum[i] - 1, tb->sbytes[i], tb->S_new[i]);
1009 
1010 		/* Insert new item into S_new[i] */
1011 		buffer_info_init_bh(tb, &bi, tb->S_new[i]);
1012 		leaf_insert_into_buf(&bi, tb->item_pos - n + tb->snum[i] - 1,
1013 				     ih, body, tb->zeroes_num);
1014 
1015 		tb->zeroes_num = tb->insert_size[0] = 0;
1016 	}
1017 }
1018 
1019 /* we append to directory item */
1020 static void balance_leaf_new_nodes_paste_dirent(struct tree_balance *tb,
1021 					 struct item_head * const ih,
1022 					 const char * const body,
1023 					 struct item_head *insert_key,
1024 					 struct buffer_head **insert_ptr,
1025 					 int i)
1026 {
1027 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1028 	struct item_head *aux_ih = item_head(tbS0, tb->item_pos);
1029 	int entry_count = ih_entry_count(aux_ih);
1030 	struct buffer_info bi;
1031 
1032 	if (entry_count - tb->sbytes[i] < tb->pos_in_item &&
1033 	    tb->pos_in_item <= entry_count) {
1034 		/* new directory entry falls into S_new[i] */
1035 
1036 		RFALSE(!tb->insert_size[0],
1037 		       "PAP-12215: insert_size is already 0");
1038 		RFALSE(tb->sbytes[i] - 1 >= entry_count,
1039 		       "PAP-12220: there are no so much entries (%d), only %d",
1040 		       tb->sbytes[i] - 1, entry_count);
1041 
1042 		/*
1043 		 * Shift snum[i]-1 items in whole.
1044 		 * Shift sbytes[i] directory entries
1045 		 * from directory item number snum[i]
1046 		 */
1047 		leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i],
1048 				tb->sbytes[i] - 1, tb->S_new[i]);
1049 
1050 		/*
1051 		 * Paste given directory entry to
1052 		 * directory item
1053 		 */
1054 		buffer_info_init_bh(tb, &bi, tb->S_new[i]);
1055 		leaf_paste_in_buffer(&bi, 0, tb->pos_in_item - entry_count +
1056 				     tb->sbytes[i] - 1, tb->insert_size[0],
1057 				     body, tb->zeroes_num);
1058 
1059 		/* paste new directory entry */
1060 		leaf_paste_entries(&bi, 0, tb->pos_in_item - entry_count +
1061 				   tb->sbytes[i] - 1, 1,
1062 				   (struct reiserfs_de_head *) body,
1063 				   body + DEH_SIZE, tb->insert_size[0]);
1064 
1065 		tb->insert_size[0] = 0;
1066 		tb->pos_in_item++;
1067 	} else {
1068 		/* new directory entry doesn't fall into S_new[i] */
1069 		leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i],
1070 				tb->sbytes[i], tb->S_new[i]);
1071 	}
1072 
1073 }
1074 
1075 static void balance_leaf_new_nodes_paste_shift(struct tree_balance *tb,
1076 					 struct item_head * const ih,
1077 					 const char * const body,
1078 					 struct item_head *insert_key,
1079 					 struct buffer_head **insert_ptr,
1080 					 int i)
1081 {
1082 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1083 	struct item_head *aux_ih = item_head(tbS0, tb->item_pos);
1084 	int n_shift, n_rem, r_zeroes_number, shift;
1085 	const char *r_body;
1086 	struct item_head *tmp;
1087 	struct buffer_info bi;
1088 
1089 	RFALSE(ih, "PAP-12210: ih must be 0");
1090 
1091 	if (is_direntry_le_ih(aux_ih)) {
1092 		balance_leaf_new_nodes_paste_dirent(tb, ih, body, insert_key,
1093 						    insert_ptr, i);
1094 		return;
1095 	}
1096 
1097 	/* regular object */
1098 
1099 
1100 	RFALSE(tb->pos_in_item != ih_item_len(item_head(tbS0, tb->item_pos)) ||
1101 	       tb->insert_size[0] <= 0,
1102 	       "PAP-12225: item too short or insert_size <= 0");
1103 
1104 	/*
1105 	 * Calculate number of bytes which must be shifted from appended item
1106 	 */
1107 	n_shift = tb->sbytes[i] - tb->insert_size[0];
1108 	if (n_shift < 0)
1109 		n_shift = 0;
1110 	leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i], n_shift,
1111 			tb->S_new[i]);
1112 
1113 	/*
1114 	 * Calculate number of bytes which must remain in body after
1115 	 * append to S_new[i]
1116 	 */
1117 	n_rem = tb->insert_size[0] - tb->sbytes[i];
1118 	if (n_rem < 0)
1119 		n_rem = 0;
1120 
1121 	/* Append part of body into S_new[0] */
1122 	buffer_info_init_bh(tb, &bi, tb->S_new[i]);
1123 	if (n_rem > tb->zeroes_num) {
1124 		r_zeroes_number = 0;
1125 		r_body = body + n_rem - tb->zeroes_num;
1126 	} else {
1127 		r_body = body;
1128 		r_zeroes_number = tb->zeroes_num - n_rem;
1129 		tb->zeroes_num -= r_zeroes_number;
1130 	}
1131 
1132 	leaf_paste_in_buffer(&bi, 0, n_shift, tb->insert_size[0] - n_rem,
1133 			     r_body, r_zeroes_number);
1134 
1135 	tmp = item_head(tb->S_new[i], 0);
1136 	shift = 0;
1137 	if (is_indirect_le_ih(tmp)) {
1138 		set_ih_free_space(tmp, 0);
1139 		shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT;
1140 	}
1141 	add_le_ih_k_offset(tmp, n_rem << shift);
1142 
1143 	tb->insert_size[0] = n_rem;
1144 	if (!n_rem)
1145 		tb->pos_in_item++;
1146 }
1147 
1148 static void balance_leaf_new_nodes_paste_whole(struct tree_balance *tb,
1149 					       struct item_head * const ih,
1150 					       const char * const body,
1151 					       struct item_head *insert_key,
1152 					       struct buffer_head **insert_ptr,
1153 					       int i)
1154 
1155 {
1156 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1157 	int n = B_NR_ITEMS(tbS0);
1158 	int leaf_mi;
1159 	struct item_head *pasted;
1160 	struct buffer_info bi;
1161 
1162 #ifdef CONFIG_REISERFS_CHECK
1163 	struct item_head *ih_check = item_head(tbS0, tb->item_pos);
1164 
1165 	if (!is_direntry_le_ih(ih_check) &&
1166 	    (tb->pos_in_item != ih_item_len(ih_check) ||
1167 	    tb->insert_size[0] <= 0))
1168 		reiserfs_panic(tb->tb_sb,
1169 			     "PAP-12235",
1170 			     "pos_in_item must be equal to ih_item_len");
1171 #endif
1172 
1173 	leaf_mi = leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i],
1174 				  tb->sbytes[i], tb->S_new[i]);
1175 
1176 	RFALSE(leaf_mi,
1177 	       "PAP-12240: unexpected value returned by leaf_move_items (%d)",
1178 	       leaf_mi);
1179 
1180 	/* paste into item */
1181 	buffer_info_init_bh(tb, &bi, tb->S_new[i]);
1182 	leaf_paste_in_buffer(&bi, tb->item_pos - n + tb->snum[i],
1183 			     tb->pos_in_item, tb->insert_size[0],
1184 			     body, tb->zeroes_num);
1185 
1186 	pasted = item_head(tb->S_new[i], tb->item_pos - n +
1187 			   tb->snum[i]);
1188 	if (is_direntry_le_ih(pasted))
1189 		leaf_paste_entries(&bi, tb->item_pos - n + tb->snum[i],
1190 				   tb->pos_in_item, 1,
1191 				   (struct reiserfs_de_head *)body,
1192 				   body + DEH_SIZE, tb->insert_size[0]);
1193 
1194 	/* if we paste to indirect item update ih_free_space */
1195 	if (is_indirect_le_ih(pasted))
1196 		set_ih_free_space(pasted, 0);
1197 
1198 	tb->zeroes_num = tb->insert_size[0] = 0;
1199 
1200 }
1201 static void balance_leaf_new_nodes_paste(struct tree_balance *tb,
1202 					 struct item_head * const ih,
1203 					 const char * const body,
1204 					 struct item_head *insert_key,
1205 					 struct buffer_head **insert_ptr,
1206 					 int i)
1207 {
1208 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1209 	int n = B_NR_ITEMS(tbS0);
1210 
1211 	/* pasted item doesn't fall into S_new[i] */
1212 	if (n - tb->snum[i] > tb->item_pos) {
1213 		leaf_move_items(LEAF_FROM_S_TO_SNEW, tb,
1214 				tb->snum[i], tb->sbytes[i], tb->S_new[i]);
1215 		return;
1216 	}
1217 
1218 	/* pasted item or part if it falls to S_new[i] */
1219 
1220 	if (tb->item_pos == n - tb->snum[i] && tb->sbytes[i] != -1)
1221 		/* we must shift part of the appended item */
1222 		balance_leaf_new_nodes_paste_shift(tb, ih, body, insert_key,
1223 						   insert_ptr, i);
1224 	else
1225 		/* item falls wholly into S_new[i] */
1226 		balance_leaf_new_nodes_paste_whole(tb, ih, body, insert_key,
1227 						   insert_ptr, i);
1228 }
1229 
1230 /* Fill new nodes that appear in place of S[0] */
1231 static void balance_leaf_new_nodes(struct tree_balance *tb,
1232 				   struct item_head * const ih,
1233 				   const char * const body,
1234 				   struct item_head *insert_key,
1235 				   struct buffer_head **insert_ptr,
1236 				   int flag)
1237 {
1238 	int i;
1239 	for (i = tb->blknum[0] - 2; i >= 0; i--) {
1240 		BUG_ON(flag != M_INSERT && flag != M_PASTE);
1241 
1242 		RFALSE(!tb->snum[i],
1243 		       "PAP-12200: snum[%d] == %d. Must be > 0", i,
1244 		       tb->snum[i]);
1245 
1246 		/* here we shift from S to S_new nodes */
1247 
1248 		tb->S_new[i] = get_FEB(tb);
1249 
1250 		/* initialized block type and tree level */
1251 		set_blkh_level(B_BLK_HEAD(tb->S_new[i]), DISK_LEAF_NODE_LEVEL);
1252 
1253 		if (flag == M_INSERT)
1254 			balance_leaf_new_nodes_insert(tb, ih, body, insert_key,
1255 						      insert_ptr, i);
1256 		else /* M_PASTE */
1257 			balance_leaf_new_nodes_paste(tb, ih, body, insert_key,
1258 						     insert_ptr, i);
1259 
1260 		memcpy(insert_key + i, leaf_key(tb->S_new[i], 0), KEY_SIZE);
1261 		insert_ptr[i] = tb->S_new[i];
1262 
1263 		RFALSE(!buffer_journaled(tb->S_new[i])
1264 		       || buffer_journal_dirty(tb->S_new[i])
1265 		       || buffer_dirty(tb->S_new[i]),
1266 		       "PAP-12247: S_new[%d] : (%b)",
1267 		       i, tb->S_new[i]);
1268 	}
1269 }
1270 
1271 static void balance_leaf_finish_node_insert(struct tree_balance *tb,
1272 					    struct item_head * const ih,
1273 					    const char * const body)
1274 {
1275 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1276 	struct buffer_info bi;
1277 	buffer_info_init_tbS0(tb, &bi);
1278 	leaf_insert_into_buf(&bi, tb->item_pos, ih, body, tb->zeroes_num);
1279 
1280 	/* If we insert the first key change the delimiting key */
1281 	if (tb->item_pos == 0) {
1282 		if (tb->CFL[0])	/* can be 0 in reiserfsck */
1283 			replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0, 0);
1284 
1285 	}
1286 }
1287 
1288 static void balance_leaf_finish_node_paste_dirent(struct tree_balance *tb,
1289 						  struct item_head * const ih,
1290 						  const char * const body)
1291 {
1292 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1293 	struct item_head *pasted = item_head(tbS0, tb->item_pos);
1294 	struct buffer_info bi;
1295 
1296 	if (tb->pos_in_item >= 0 && tb->pos_in_item <= ih_entry_count(pasted)) {
1297 		RFALSE(!tb->insert_size[0],
1298 		       "PAP-12260: insert_size is 0 already");
1299 
1300 		/* prepare space */
1301 		buffer_info_init_tbS0(tb, &bi);
1302 		leaf_paste_in_buffer(&bi, tb->item_pos, tb->pos_in_item,
1303 				     tb->insert_size[0], body, tb->zeroes_num);
1304 
1305 		/* paste entry */
1306 		leaf_paste_entries(&bi, tb->item_pos, tb->pos_in_item, 1,
1307 				   (struct reiserfs_de_head *)body,
1308 				   body + DEH_SIZE, tb->insert_size[0]);
1309 
1310 		if (!tb->item_pos && !tb->pos_in_item) {
1311 			RFALSE(!tb->CFL[0] || !tb->L[0],
1312 			       "PAP-12270: CFL[0]/L[0] must  be specified");
1313 			if (tb->CFL[0])
1314 				replace_key(tb, tb->CFL[0], tb->lkey[0],
1315 					    tbS0, 0);
1316 		}
1317 
1318 		tb->insert_size[0] = 0;
1319 	}
1320 }
1321 
1322 static void balance_leaf_finish_node_paste(struct tree_balance *tb,
1323 					   struct item_head * const ih,
1324 					   const char * const body)
1325 {
1326 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1327 	struct buffer_info bi;
1328 	struct item_head *pasted = item_head(tbS0, tb->item_pos);
1329 
1330 	/* when directory, may be new entry already pasted */
1331 	if (is_direntry_le_ih(pasted)) {
1332 		balance_leaf_finish_node_paste_dirent(tb, ih, body);
1333 		return;
1334 	}
1335 
1336 	/* regular object */
1337 
1338 	if (tb->pos_in_item == ih_item_len(pasted)) {
1339 		RFALSE(tb->insert_size[0] <= 0,
1340 		       "PAP-12275: insert size must not be %d",
1341 		       tb->insert_size[0]);
1342 		buffer_info_init_tbS0(tb, &bi);
1343 		leaf_paste_in_buffer(&bi, tb->item_pos,
1344 				     tb->pos_in_item, tb->insert_size[0], body,
1345 				     tb->zeroes_num);
1346 
1347 		if (is_indirect_le_ih(pasted))
1348 			set_ih_free_space(pasted, 0);
1349 
1350 		tb->insert_size[0] = 0;
1351 	}
1352 #ifdef CONFIG_REISERFS_CHECK
1353 	else if (tb->insert_size[0]) {
1354 		print_cur_tb("12285");
1355 		reiserfs_panic(tb->tb_sb, "PAP-12285",
1356 		    "insert_size must be 0 (%d)", tb->insert_size[0]);
1357 	}
1358 #endif
1359 }
1360 
1361 /*
1362  * if the affected item was not wholly shifted then we
1363  * perform all necessary operations on that part or whole
1364  * of the affected item which remains in S
1365  */
1366 static void balance_leaf_finish_node(struct tree_balance *tb,
1367 				      struct item_head * const ih,
1368 				      const char * const body, int flag)
1369 {
1370 	/* if we must insert or append into buffer S[0] */
1371 	if (0 <= tb->item_pos && tb->item_pos < tb->s0num) {
1372 		if (flag == M_INSERT)
1373 			balance_leaf_finish_node_insert(tb, ih, body);
1374 		else /* M_PASTE */
1375 			balance_leaf_finish_node_paste(tb, ih, body);
1376 	}
1377 }
1378 
1379 /**
1380  * balance_leaf - reiserfs tree balancing algorithm
1381  * @tb: tree balance state
1382  * @ih: item header of inserted item (little endian)
1383  * @body: body of inserted item or bytes to paste
1384  * @flag: i - insert, d - delete, c - cut, p - paste (see do_balance)
1385  * passed back:
1386  * @insert_key: key to insert new nodes
1387  * @insert_ptr: array of nodes to insert at the next level
1388  *
1389  * In our processing of one level we sometimes determine what must be
1390  * inserted into the next higher level.  This insertion consists of a
1391  * key or two keys and their corresponding pointers.
1392  */
1393 static int balance_leaf(struct tree_balance *tb, struct item_head *ih,
1394 			const char *body, int flag,
1395 			struct item_head *insert_key,
1396 			struct buffer_head **insert_ptr)
1397 {
1398 	struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
1399 
1400 	PROC_INFO_INC(tb->tb_sb, balance_at[0]);
1401 
1402 	/* Make balance in case insert_size[0] < 0 */
1403 	if (tb->insert_size[0] < 0)
1404 		return balance_leaf_when_delete(tb, flag);
1405 
1406 	tb->item_pos = PATH_LAST_POSITION(tb->tb_path),
1407 	tb->pos_in_item = tb->tb_path->pos_in_item,
1408 	tb->zeroes_num = 0;
1409 	if (flag == M_INSERT && !body)
1410 		tb->zeroes_num = ih_item_len(ih);
1411 
1412 	/*
1413 	 * for indirect item pos_in_item is measured in unformatted node
1414 	 * pointers. Recalculate to bytes
1415 	 */
1416 	if (flag != M_INSERT
1417 	    && is_indirect_le_ih(item_head(tbS0, tb->item_pos)))
1418 		tb->pos_in_item *= UNFM_P_SIZE;
1419 
1420 	body += balance_leaf_left(tb, ih, body, flag);
1421 
1422 	/* tb->lnum[0] > 0 */
1423 	/* Calculate new item position */
1424 	tb->item_pos -= (tb->lnum[0] - ((tb->lbytes != -1) ? 1 : 0));
1425 
1426 	balance_leaf_right(tb, ih, body, flag);
1427 
1428 	/* tb->rnum[0] > 0 */
1429 	RFALSE(tb->blknum[0] > 3,
1430 	       "PAP-12180: blknum can not be %d. It must be <= 3", tb->blknum[0]);
1431 	RFALSE(tb->blknum[0] < 0,
1432 	       "PAP-12185: blknum can not be %d. It must be >= 0", tb->blknum[0]);
1433 
1434 	/*
1435 	 * if while adding to a node we discover that it is possible to split
1436 	 * it in two, and merge the left part into the left neighbor and the
1437 	 * right part into the right neighbor, eliminating the node
1438 	 */
1439 	if (tb->blknum[0] == 0) {	/* node S[0] is empty now */
1440 
1441 		RFALSE(!tb->lnum[0] || !tb->rnum[0],
1442 		       "PAP-12190: lnum and rnum must not be zero");
1443 		/*
1444 		 * if insertion was done before 0-th position in R[0], right
1445 		 * delimiting key of the tb->L[0]'s and left delimiting key are
1446 		 * not set correctly
1447 		 */
1448 		if (tb->CFL[0]) {
1449 			if (!tb->CFR[0])
1450 				reiserfs_panic(tb->tb_sb, "vs-12195",
1451 					       "CFR not initialized");
1452 			copy_key(internal_key(tb->CFL[0], tb->lkey[0]),
1453 				 internal_key(tb->CFR[0], tb->rkey[0]));
1454 			do_balance_mark_internal_dirty(tb, tb->CFL[0], 0);
1455 		}
1456 
1457 		reiserfs_invalidate_buffer(tb, tbS0);
1458 		return 0;
1459 	}
1460 
1461 	balance_leaf_new_nodes(tb, ih, body, insert_key, insert_ptr, flag);
1462 
1463 	balance_leaf_finish_node(tb, ih, body, flag);
1464 
1465 #ifdef CONFIG_REISERFS_CHECK
1466 	if (flag == M_PASTE && tb->insert_size[0]) {
1467 		print_cur_tb("12290");
1468 		reiserfs_panic(tb->tb_sb,
1469 			       "PAP-12290", "insert_size is still not 0 (%d)",
1470 			       tb->insert_size[0]);
1471 	}
1472 #endif
1473 
1474 	/* Leaf level of the tree is balanced (end of balance_leaf) */
1475 	return 0;
1476 }
1477 
1478 /* Make empty node */
1479 void make_empty_node(struct buffer_info *bi)
1480 {
1481 	struct block_head *blkh;
1482 
1483 	RFALSE(bi->bi_bh == NULL, "PAP-12295: pointer to the buffer is NULL");
1484 
1485 	blkh = B_BLK_HEAD(bi->bi_bh);
1486 	set_blkh_nr_item(blkh, 0);
1487 	set_blkh_free_space(blkh, MAX_CHILD_SIZE(bi->bi_bh));
1488 
1489 	if (bi->bi_parent)
1490 		B_N_CHILD(bi->bi_parent, bi->bi_position)->dc_size = 0;	/* Endian safe if 0 */
1491 }
1492 
1493 /* Get first empty buffer */
1494 struct buffer_head *get_FEB(struct tree_balance *tb)
1495 {
1496 	int i;
1497 	struct buffer_info bi;
1498 
1499 	for (i = 0; i < MAX_FEB_SIZE; i++)
1500 		if (tb->FEB[i] != NULL)
1501 			break;
1502 
1503 	if (i == MAX_FEB_SIZE)
1504 		reiserfs_panic(tb->tb_sb, "vs-12300", "FEB list is empty");
1505 
1506 	buffer_info_init_bh(tb, &bi, tb->FEB[i]);
1507 	make_empty_node(&bi);
1508 	set_buffer_uptodate(tb->FEB[i]);
1509 	tb->used[i] = tb->FEB[i];
1510 	tb->FEB[i] = NULL;
1511 
1512 	return tb->used[i];
1513 }
1514 
1515 /* This is now used because reiserfs_free_block has to be able to schedule. */
1516 static void store_thrown(struct tree_balance *tb, struct buffer_head *bh)
1517 {
1518 	int i;
1519 
1520 	if (buffer_dirty(bh))
1521 		reiserfs_warning(tb->tb_sb, "reiserfs-12320",
1522 				 "called with dirty buffer");
1523 	for (i = 0; i < ARRAY_SIZE(tb->thrown); i++)
1524 		if (!tb->thrown[i]) {
1525 			tb->thrown[i] = bh;
1526 			get_bh(bh);	/* free_thrown puts this */
1527 			return;
1528 		}
1529 	reiserfs_warning(tb->tb_sb, "reiserfs-12321",
1530 			 "too many thrown buffers");
1531 }
1532 
1533 static void free_thrown(struct tree_balance *tb)
1534 {
1535 	int i;
1536 	b_blocknr_t blocknr;
1537 	for (i = 0; i < ARRAY_SIZE(tb->thrown); i++) {
1538 		if (tb->thrown[i]) {
1539 			blocknr = tb->thrown[i]->b_blocknr;
1540 			if (buffer_dirty(tb->thrown[i]))
1541 				reiserfs_warning(tb->tb_sb, "reiserfs-12322",
1542 						 "called with dirty buffer %d",
1543 						 blocknr);
1544 			brelse(tb->thrown[i]);	/* incremented in store_thrown */
1545 			reiserfs_free_block(tb->transaction_handle, NULL,
1546 					    blocknr, 0);
1547 		}
1548 	}
1549 }
1550 
1551 void reiserfs_invalidate_buffer(struct tree_balance *tb, struct buffer_head *bh)
1552 {
1553 	struct block_head *blkh;
1554 	blkh = B_BLK_HEAD(bh);
1555 	set_blkh_level(blkh, FREE_LEVEL);
1556 	set_blkh_nr_item(blkh, 0);
1557 
1558 	clear_buffer_dirty(bh);
1559 	store_thrown(tb, bh);
1560 }
1561 
1562 /* Replace n_dest'th key in buffer dest by n_src'th key of buffer src.*/
1563 void replace_key(struct tree_balance *tb, struct buffer_head *dest, int n_dest,
1564 		 struct buffer_head *src, int n_src)
1565 {
1566 
1567 	RFALSE(dest == NULL || src == NULL,
1568 	       "vs-12305: source or destination buffer is 0 (src=%p, dest=%p)",
1569 	       src, dest);
1570 	RFALSE(!B_IS_KEYS_LEVEL(dest),
1571 	       "vs-12310: invalid level (%z) for destination buffer. dest must be leaf",
1572 	       dest);
1573 	RFALSE(n_dest < 0 || n_src < 0,
1574 	       "vs-12315: src(%d) or dest(%d) key number < 0", n_src, n_dest);
1575 	RFALSE(n_dest >= B_NR_ITEMS(dest) || n_src >= B_NR_ITEMS(src),
1576 	       "vs-12320: src(%d(%d)) or dest(%d(%d)) key number is too big",
1577 	       n_src, B_NR_ITEMS(src), n_dest, B_NR_ITEMS(dest));
1578 
1579 	if (B_IS_ITEMS_LEVEL(src))
1580 		/* source buffer contains leaf node */
1581 		memcpy(internal_key(dest, n_dest), item_head(src, n_src),
1582 		       KEY_SIZE);
1583 	else
1584 		memcpy(internal_key(dest, n_dest), internal_key(src, n_src),
1585 		       KEY_SIZE);
1586 
1587 	do_balance_mark_internal_dirty(tb, dest, 0);
1588 }
1589 
1590 int get_left_neighbor_position(struct tree_balance *tb, int h)
1591 {
1592 	int Sh_position = PATH_H_POSITION(tb->tb_path, h + 1);
1593 
1594 	RFALSE(PATH_H_PPARENT(tb->tb_path, h) == NULL || tb->FL[h] == NULL,
1595 	       "vs-12325: FL[%d](%p) or F[%d](%p) does not exist",
1596 	       h, tb->FL[h], h, PATH_H_PPARENT(tb->tb_path, h));
1597 
1598 	if (Sh_position == 0)
1599 		return B_NR_ITEMS(tb->FL[h]);
1600 	else
1601 		return Sh_position - 1;
1602 }
1603 
1604 int get_right_neighbor_position(struct tree_balance *tb, int h)
1605 {
1606 	int Sh_position = PATH_H_POSITION(tb->tb_path, h + 1);
1607 
1608 	RFALSE(PATH_H_PPARENT(tb->tb_path, h) == NULL || tb->FR[h] == NULL,
1609 	       "vs-12330: F[%d](%p) or FR[%d](%p) does not exist",
1610 	       h, PATH_H_PPARENT(tb->tb_path, h), h, tb->FR[h]);
1611 
1612 	if (Sh_position == B_NR_ITEMS(PATH_H_PPARENT(tb->tb_path, h)))
1613 		return 0;
1614 	else
1615 		return Sh_position + 1;
1616 }
1617 
1618 #ifdef CONFIG_REISERFS_CHECK
1619 
1620 int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value);
1621 static void check_internal_node(struct super_block *s, struct buffer_head *bh,
1622 				char *mes)
1623 {
1624 	struct disk_child *dc;
1625 	int i;
1626 
1627 	RFALSE(!bh, "PAP-12336: bh == 0");
1628 
1629 	if (!bh || !B_IS_IN_TREE(bh))
1630 		return;
1631 
1632 	RFALSE(!buffer_dirty(bh) &&
1633 	       !(buffer_journaled(bh) || buffer_journal_dirty(bh)),
1634 	       "PAP-12337: buffer (%b) must be dirty", bh);
1635 	dc = B_N_CHILD(bh, 0);
1636 
1637 	for (i = 0; i <= B_NR_ITEMS(bh); i++, dc++) {
1638 		if (!is_reusable(s, dc_block_number(dc), 1)) {
1639 			print_cur_tb(mes);
1640 			reiserfs_panic(s, "PAP-12338",
1641 				       "invalid child pointer %y in %b",
1642 				       dc, bh);
1643 		}
1644 	}
1645 }
1646 
1647 static int locked_or_not_in_tree(struct tree_balance *tb,
1648 				  struct buffer_head *bh, char *which)
1649 {
1650 	if ((!buffer_journal_prepared(bh) && buffer_locked(bh)) ||
1651 	    !B_IS_IN_TREE(bh)) {
1652 		reiserfs_warning(tb->tb_sb, "vs-12339", "%s (%b)", which, bh);
1653 		return 1;
1654 	}
1655 	return 0;
1656 }
1657 
1658 static int check_before_balancing(struct tree_balance *tb)
1659 {
1660 	int retval = 0;
1661 
1662 	if (REISERFS_SB(tb->tb_sb)->cur_tb) {
1663 		reiserfs_panic(tb->tb_sb, "vs-12335", "suspect that schedule "
1664 			       "occurred based on cur_tb not being null at "
1665 			       "this point in code. do_balance cannot properly "
1666 			       "handle concurrent tree accesses on a same "
1667 			       "mount point.");
1668 	}
1669 
1670 	/*
1671 	 * double check that buffers that we will modify are unlocked.
1672 	 * (fix_nodes should already have prepped all of these for us).
1673 	 */
1674 	if (tb->lnum[0]) {
1675 		retval |= locked_or_not_in_tree(tb, tb->L[0], "L[0]");
1676 		retval |= locked_or_not_in_tree(tb, tb->FL[0], "FL[0]");
1677 		retval |= locked_or_not_in_tree(tb, tb->CFL[0], "CFL[0]");
1678 		check_leaf(tb->L[0]);
1679 	}
1680 	if (tb->rnum[0]) {
1681 		retval |= locked_or_not_in_tree(tb, tb->R[0], "R[0]");
1682 		retval |= locked_or_not_in_tree(tb, tb->FR[0], "FR[0]");
1683 		retval |= locked_or_not_in_tree(tb, tb->CFR[0], "CFR[0]");
1684 		check_leaf(tb->R[0]);
1685 	}
1686 	retval |= locked_or_not_in_tree(tb, PATH_PLAST_BUFFER(tb->tb_path),
1687 					"S[0]");
1688 	check_leaf(PATH_PLAST_BUFFER(tb->tb_path));
1689 
1690 	return retval;
1691 }
1692 
1693 static void check_after_balance_leaf(struct tree_balance *tb)
1694 {
1695 	if (tb->lnum[0]) {
1696 		if (B_FREE_SPACE(tb->L[0]) !=
1697 		    MAX_CHILD_SIZE(tb->L[0]) -
1698 		    dc_size(B_N_CHILD
1699 			    (tb->FL[0], get_left_neighbor_position(tb, 0)))) {
1700 			print_cur_tb("12221");
1701 			reiserfs_panic(tb->tb_sb, "PAP-12355",
1702 				       "shift to left was incorrect");
1703 		}
1704 	}
1705 	if (tb->rnum[0]) {
1706 		if (B_FREE_SPACE(tb->R[0]) !=
1707 		    MAX_CHILD_SIZE(tb->R[0]) -
1708 		    dc_size(B_N_CHILD
1709 			    (tb->FR[0], get_right_neighbor_position(tb, 0)))) {
1710 			print_cur_tb("12222");
1711 			reiserfs_panic(tb->tb_sb, "PAP-12360",
1712 				       "shift to right was incorrect");
1713 		}
1714 	}
1715 	if (PATH_H_PBUFFER(tb->tb_path, 1) &&
1716 	    (B_FREE_SPACE(PATH_H_PBUFFER(tb->tb_path, 0)) !=
1717 	     (MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)) -
1718 	      dc_size(B_N_CHILD(PATH_H_PBUFFER(tb->tb_path, 1),
1719 				PATH_H_POSITION(tb->tb_path, 1)))))) {
1720 		int left = B_FREE_SPACE(PATH_H_PBUFFER(tb->tb_path, 0));
1721 		int right = (MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)) -
1722 			     dc_size(B_N_CHILD(PATH_H_PBUFFER(tb->tb_path, 1),
1723 					       PATH_H_POSITION(tb->tb_path,
1724 							       1))));
1725 		print_cur_tb("12223");
1726 		reiserfs_warning(tb->tb_sb, "reiserfs-12363",
1727 				 "B_FREE_SPACE (PATH_H_PBUFFER(tb->tb_path,0)) = %d; "
1728 				 "MAX_CHILD_SIZE (%d) - dc_size( %y, %d ) [%d] = %d",
1729 				 left,
1730 				 MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)),
1731 				 PATH_H_PBUFFER(tb->tb_path, 1),
1732 				 PATH_H_POSITION(tb->tb_path, 1),
1733 				 dc_size(B_N_CHILD
1734 					 (PATH_H_PBUFFER(tb->tb_path, 1),
1735 					  PATH_H_POSITION(tb->tb_path, 1))),
1736 				 right);
1737 		reiserfs_panic(tb->tb_sb, "PAP-12365", "S is incorrect");
1738 	}
1739 }
1740 
1741 static void check_leaf_level(struct tree_balance *tb)
1742 {
1743 	check_leaf(tb->L[0]);
1744 	check_leaf(tb->R[0]);
1745 	check_leaf(PATH_PLAST_BUFFER(tb->tb_path));
1746 }
1747 
1748 static void check_internal_levels(struct tree_balance *tb)
1749 {
1750 	int h;
1751 
1752 	/* check all internal nodes */
1753 	for (h = 1; tb->insert_size[h]; h++) {
1754 		check_internal_node(tb->tb_sb, PATH_H_PBUFFER(tb->tb_path, h),
1755 				    "BAD BUFFER ON PATH");
1756 		if (tb->lnum[h])
1757 			check_internal_node(tb->tb_sb, tb->L[h], "BAD L");
1758 		if (tb->rnum[h])
1759 			check_internal_node(tb->tb_sb, tb->R[h], "BAD R");
1760 	}
1761 
1762 }
1763 
1764 #endif
1765 
1766 /*
1767  * Now we have all of the buffers that must be used in balancing of
1768  * the tree.  We rely on the assumption that schedule() will not occur
1769  * while do_balance works. ( Only interrupt handlers are acceptable.)
1770  * We balance the tree according to the analysis made before this,
1771  * using buffers already obtained.  For SMP support it will someday be
1772  * necessary to add ordered locking of tb.
1773  */
1774 
1775 /*
1776  * Some interesting rules of balancing:
1777  * we delete a maximum of two nodes per level per balancing: we never
1778  * delete R, when we delete two of three nodes L, S, R then we move
1779  * them into R.
1780  *
1781  * we only delete L if we are deleting two nodes, if we delete only
1782  * one node we delete S
1783  *
1784  * if we shift leaves then we shift as much as we can: this is a
1785  * deliberate policy of extremism in node packing which results in
1786  * higher average utilization after repeated random balance operations
1787  * at the cost of more memory copies and more balancing as a result of
1788  * small insertions to full nodes.
1789  *
1790  * if we shift internal nodes we try to evenly balance the node
1791  * utilization, with consequent less balancing at the cost of lower
1792  * utilization.
1793  *
1794  * one could argue that the policy for directories in leaves should be
1795  * that of internal nodes, but we will wait until another day to
1796  * evaluate this....  It would be nice to someday measure and prove
1797  * these assumptions as to what is optimal....
1798  */
1799 
1800 static inline void do_balance_starts(struct tree_balance *tb)
1801 {
1802 	/* use print_cur_tb() to see initial state of struct tree_balance */
1803 
1804 	/* store_print_tb (tb); */
1805 
1806 	/* do not delete, just comment it out */
1807 	/*
1808 	print_tb(flag, PATH_LAST_POSITION(tb->tb_path),
1809 		 tb->tb_path->pos_in_item, tb, "check");
1810 	*/
1811 	RFALSE(check_before_balancing(tb), "PAP-12340: locked buffers in TB");
1812 #ifdef CONFIG_REISERFS_CHECK
1813 	REISERFS_SB(tb->tb_sb)->cur_tb = tb;
1814 #endif
1815 }
1816 
1817 static inline void do_balance_completed(struct tree_balance *tb)
1818 {
1819 
1820 #ifdef CONFIG_REISERFS_CHECK
1821 	check_leaf_level(tb);
1822 	check_internal_levels(tb);
1823 	REISERFS_SB(tb->tb_sb)->cur_tb = NULL;
1824 #endif
1825 
1826 	/*
1827 	 * reiserfs_free_block is no longer schedule safe.  So, we need to
1828 	 * put the buffers we want freed on the thrown list during do_balance,
1829 	 * and then free them now
1830 	 */
1831 
1832 	REISERFS_SB(tb->tb_sb)->s_do_balance++;
1833 
1834 	/* release all nodes hold to perform the balancing */
1835 	unfix_nodes(tb);
1836 
1837 	free_thrown(tb);
1838 }
1839 
1840 /*
1841  * do_balance - balance the tree
1842  *
1843  * @tb: tree_balance structure
1844  * @ih: item header of inserted item
1845  * @body: body of inserted item or bytes to paste
1846  * @flag: 'i' - insert, 'd' - delete, 'c' - cut, 'p' paste
1847  *
1848  * Cut means delete part of an item (includes removing an entry from a
1849  * directory).
1850  *
1851  * Delete means delete whole item.
1852  *
1853  * Insert means add a new item into the tree.
1854  *
1855  * Paste means to append to the end of an existing file or to
1856  * insert a directory entry.
1857  */
1858 void do_balance(struct tree_balance *tb, struct item_head *ih,
1859 		const char *body, int flag)
1860 {
1861 	int child_pos;		/* position of a child node in its parent */
1862 	int h;			/* level of the tree being processed */
1863 
1864 	/*
1865 	 * in our processing of one level we sometimes determine what
1866 	 * must be inserted into the next higher level.  This insertion
1867 	 * consists of a key or two keys and their corresponding
1868 	 * pointers
1869 	 */
1870 	struct item_head insert_key[2];
1871 
1872 	/* inserted node-ptrs for the next level */
1873 	struct buffer_head *insert_ptr[2];
1874 
1875 	tb->tb_mode = flag;
1876 	tb->need_balance_dirty = 0;
1877 
1878 	if (FILESYSTEM_CHANGED_TB(tb)) {
1879 		reiserfs_panic(tb->tb_sb, "clm-6000", "fs generation has "
1880 			       "changed");
1881 	}
1882 	/* if we have no real work to do  */
1883 	if (!tb->insert_size[0]) {
1884 		reiserfs_warning(tb->tb_sb, "PAP-12350",
1885 				 "insert_size == 0, mode == %c", flag);
1886 		unfix_nodes(tb);
1887 		return;
1888 	}
1889 
1890 	atomic_inc(&fs_generation(tb->tb_sb));
1891 	do_balance_starts(tb);
1892 
1893 	/*
1894 	 * balance_leaf returns 0 except if combining L R and S into
1895 	 * one node.  see balance_internal() for explanation of this
1896 	 * line of code.
1897 	 */
1898 	child_pos = PATH_H_B_ITEM_ORDER(tb->tb_path, 0) +
1899 	    balance_leaf(tb, ih, body, flag, insert_key, insert_ptr);
1900 
1901 #ifdef CONFIG_REISERFS_CHECK
1902 	check_after_balance_leaf(tb);
1903 #endif
1904 
1905 	/* Balance internal level of the tree. */
1906 	for (h = 1; h < MAX_HEIGHT && tb->insert_size[h]; h++)
1907 		child_pos = balance_internal(tb, h, child_pos, insert_key,
1908 					     insert_ptr);
1909 
1910 	do_balance_completed(tb);
1911 }
1912