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