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
  19static 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
  28static 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
  37static 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
  46static 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
  56inline 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
  77static 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] */
 109static 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
 146static 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 */
 239static 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
 289static 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
 357static 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
 419static 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 */
 538static 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
 592static 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] */
 605static 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
 627static 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
 716static 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
 767static 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
 845static 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
 889static 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] */
 913static 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
 928static 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 */
1020static 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
1075static 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
1148static 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}
1201static 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] */
1231static 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
1271static 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
1288static 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
1322static 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 */
1366static 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 */
1393static 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 */
1479void 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 */
1494struct 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. */
1516static 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
1533static 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
1551void 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.*/
1563void 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
1590int 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
1604int 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
1620int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value);
1621static 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
1647static 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
1658static 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
1693static 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
1741static 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
1748static 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
1800static 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
1817static 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 */
1858void 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}