| /* |
| * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README |
| */ |
| |
| /* |
| * Now we have all buffers that must be used in balancing of the tree |
| * Further calculations can not cause schedule(), and thus the buffer |
| * tree will be stable until the balancing will be finished |
| * balance the tree according to the analysis made before, |
| * and using buffers obtained after all above. |
| */ |
| |
| #include <linux/uaccess.h> |
| #include <linux/time.h> |
| #include "reiserfs.h" |
| #include <linux/buffer_head.h> |
| #include <linux/kernel.h> |
| |
| static inline void buffer_info_init_left(struct tree_balance *tb, |
| struct buffer_info *bi) |
| { |
| bi->tb = tb; |
| bi->bi_bh = tb->L[0]; |
| bi->bi_parent = tb->FL[0]; |
| bi->bi_position = get_left_neighbor_position(tb, 0); |
| } |
| |
| static inline void buffer_info_init_right(struct tree_balance *tb, |
| struct buffer_info *bi) |
| { |
| bi->tb = tb; |
| bi->bi_bh = tb->R[0]; |
| bi->bi_parent = tb->FR[0]; |
| bi->bi_position = get_right_neighbor_position(tb, 0); |
| } |
| |
| static inline void buffer_info_init_tbS0(struct tree_balance *tb, |
| struct buffer_info *bi) |
| { |
| bi->tb = tb; |
| bi->bi_bh = PATH_PLAST_BUFFER(tb->tb_path); |
| bi->bi_parent = PATH_H_PPARENT(tb->tb_path, 0); |
| bi->bi_position = PATH_H_POSITION(tb->tb_path, 1); |
| } |
| |
| static inline void buffer_info_init_bh(struct tree_balance *tb, |
| struct buffer_info *bi, |
| struct buffer_head *bh) |
| { |
| bi->tb = tb; |
| bi->bi_bh = bh; |
| bi->bi_parent = NULL; |
| bi->bi_position = 0; |
| } |
| |
| inline void do_balance_mark_leaf_dirty(struct tree_balance *tb, |
| struct buffer_head *bh, int flag) |
| { |
| journal_mark_dirty(tb->transaction_handle, bh); |
| } |
| |
| #define do_balance_mark_internal_dirty do_balance_mark_leaf_dirty |
| #define do_balance_mark_sb_dirty do_balance_mark_leaf_dirty |
| |
| /* |
| * summary: |
| * if deleting something ( tb->insert_size[0] < 0 ) |
| * return(balance_leaf_when_delete()); (flag d handled here) |
| * else |
| * if lnum is larger than 0 we put items into the left node |
| * if rnum is larger than 0 we put items into the right node |
| * if snum1 is larger than 0 we put items into the new node s1 |
| * if snum2 is larger than 0 we put items into the new node s2 |
| * Note that all *num* count new items being created. |
| */ |
| |
| static void balance_leaf_when_delete_del(struct tree_balance *tb) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int item_pos = PATH_LAST_POSITION(tb->tb_path); |
| struct buffer_info bi; |
| #ifdef CONFIG_REISERFS_CHECK |
| struct item_head *ih = item_head(tbS0, item_pos); |
| #endif |
| |
| RFALSE(ih_item_len(ih) + IH_SIZE != -tb->insert_size[0], |
| "vs-12013: mode Delete, insert size %d, ih to be deleted %h", |
| -tb->insert_size[0], ih); |
| |
| buffer_info_init_tbS0(tb, &bi); |
| leaf_delete_items(&bi, 0, item_pos, 1, -1); |
| |
| if (!item_pos && tb->CFL[0]) { |
| if (B_NR_ITEMS(tbS0)) { |
| replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0, 0); |
| } else { |
| if (!PATH_H_POSITION(tb->tb_path, 1)) |
| replace_key(tb, tb->CFL[0], tb->lkey[0], |
| PATH_H_PPARENT(tb->tb_path, 0), 0); |
| } |
| } |
| |
| RFALSE(!item_pos && !tb->CFL[0], |
| "PAP-12020: tb->CFL[0]==%p, tb->L[0]==%p", tb->CFL[0], |
| tb->L[0]); |
| } |
| |
| /* cut item in S[0] */ |
| static void balance_leaf_when_delete_cut(struct tree_balance *tb) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int item_pos = PATH_LAST_POSITION(tb->tb_path); |
| struct item_head *ih = item_head(tbS0, item_pos); |
| int pos_in_item = tb->tb_path->pos_in_item; |
| struct buffer_info bi; |
| buffer_info_init_tbS0(tb, &bi); |
| |
| if (is_direntry_le_ih(ih)) { |
| /* |
| * UFS unlink semantics are such that you can only |
| * delete one directory entry at a time. |
| * |
| * when we cut a directory tb->insert_size[0] means |
| * number of entries to be cut (always 1) |
| */ |
| tb->insert_size[0] = -1; |
| leaf_cut_from_buffer(&bi, item_pos, pos_in_item, |
| -tb->insert_size[0]); |
| |
| RFALSE(!item_pos && !pos_in_item && !tb->CFL[0], |
| "PAP-12030: can not change delimiting key. CFL[0]=%p", |
| tb->CFL[0]); |
| |
| if (!item_pos && !pos_in_item && tb->CFL[0]) |
| replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0, 0); |
| } else { |
| leaf_cut_from_buffer(&bi, item_pos, pos_in_item, |
| -tb->insert_size[0]); |
| |
| RFALSE(!ih_item_len(ih), |
| "PAP-12035: cut must leave non-zero dynamic " |
| "length of item"); |
| } |
| } |
| |
| static int balance_leaf_when_delete_left(struct tree_balance *tb) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int n = B_NR_ITEMS(tbS0); |
| |
| /* L[0] must be joined with S[0] */ |
| if (tb->lnum[0] == -1) { |
| /* R[0] must be also joined with S[0] */ |
| if (tb->rnum[0] == -1) { |
| if (tb->FR[0] == PATH_H_PPARENT(tb->tb_path, 0)) { |
| /* |
| * all contents of all the |
| * 3 buffers will be in L[0] |
| */ |
| if (PATH_H_POSITION(tb->tb_path, 1) == 0 && |
| 1 < B_NR_ITEMS(tb->FR[0])) |
| replace_key(tb, tb->CFL[0], |
| tb->lkey[0], tb->FR[0], 1); |
| |
| leaf_move_items(LEAF_FROM_S_TO_L, tb, n, -1, |
| NULL); |
| leaf_move_items(LEAF_FROM_R_TO_L, tb, |
| B_NR_ITEMS(tb->R[0]), -1, |
| NULL); |
| |
| reiserfs_invalidate_buffer(tb, tbS0); |
| reiserfs_invalidate_buffer(tb, tb->R[0]); |
| |
| return 0; |
| } |
| |
| /* all contents of all the 3 buffers will be in R[0] */ |
| leaf_move_items(LEAF_FROM_S_TO_R, tb, n, -1, NULL); |
| leaf_move_items(LEAF_FROM_L_TO_R, tb, |
| B_NR_ITEMS(tb->L[0]), -1, NULL); |
| |
| /* right_delimiting_key is correct in R[0] */ |
| replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0); |
| |
| reiserfs_invalidate_buffer(tb, tbS0); |
| reiserfs_invalidate_buffer(tb, tb->L[0]); |
| |
| return -1; |
| } |
| |
| RFALSE(tb->rnum[0] != 0, |
| "PAP-12045: rnum must be 0 (%d)", tb->rnum[0]); |
| /* all contents of L[0] and S[0] will be in L[0] */ |
| leaf_shift_left(tb, n, -1); |
| |
| reiserfs_invalidate_buffer(tb, tbS0); |
| |
| return 0; |
| } |
| |
| /* |
| * a part of contents of S[0] will be in L[0] and |
| * the rest part of S[0] will be in R[0] |
| */ |
| |
| RFALSE((tb->lnum[0] + tb->rnum[0] < n) || |
| (tb->lnum[0] + tb->rnum[0] > n + 1), |
| "PAP-12050: rnum(%d) and lnum(%d) and item " |
| "number(%d) in S[0] are not consistent", |
| tb->rnum[0], tb->lnum[0], n); |
| RFALSE((tb->lnum[0] + tb->rnum[0] == n) && |
| (tb->lbytes != -1 || tb->rbytes != -1), |
| "PAP-12055: bad rbytes (%d)/lbytes (%d) " |
| "parameters when items are not split", |
| tb->rbytes, tb->lbytes); |
| RFALSE((tb->lnum[0] + tb->rnum[0] == n + 1) && |
| (tb->lbytes < 1 || tb->rbytes != -1), |
| "PAP-12060: bad rbytes (%d)/lbytes (%d) " |
| "parameters when items are split", |
| tb->rbytes, tb->lbytes); |
| |
| leaf_shift_left(tb, tb->lnum[0], tb->lbytes); |
| leaf_shift_right(tb, tb->rnum[0], tb->rbytes); |
| |
| reiserfs_invalidate_buffer(tb, tbS0); |
| |
| return 0; |
| } |
| |
| /* |
| * Balance leaf node in case of delete or cut: insert_size[0] < 0 |
| * |
| * lnum, rnum can have values >= -1 |
| * -1 means that the neighbor must be joined with S |
| * 0 means that nothing should be done with the neighbor |
| * >0 means to shift entirely or partly the specified number of items |
| * to the neighbor |
| */ |
| static int balance_leaf_when_delete(struct tree_balance *tb, int flag) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int item_pos = PATH_LAST_POSITION(tb->tb_path); |
| struct buffer_info bi; |
| int n; |
| struct item_head *ih; |
| |
| RFALSE(tb->FR[0] && B_LEVEL(tb->FR[0]) != DISK_LEAF_NODE_LEVEL + 1, |
| "vs- 12000: level: wrong FR %z", tb->FR[0]); |
| RFALSE(tb->blknum[0] > 1, |
| "PAP-12005: tb->blknum == %d, can not be > 1", tb->blknum[0]); |
| RFALSE(!tb->blknum[0] && !PATH_H_PPARENT(tb->tb_path, 0), |
| "PAP-12010: tree can not be empty"); |
| |
| ih = item_head(tbS0, item_pos); |
| buffer_info_init_tbS0(tb, &bi); |
| |
| /* Delete or truncate the item */ |
| |
| BUG_ON(flag != M_DELETE && flag != M_CUT); |
| if (flag == M_DELETE) |
| balance_leaf_when_delete_del(tb); |
| else /* M_CUT */ |
| balance_leaf_when_delete_cut(tb); |
| |
| |
| /* |
| * the rule is that no shifting occurs unless by shifting |
| * a node can be freed |
| */ |
| n = B_NR_ITEMS(tbS0); |
| |
| |
| /* L[0] takes part in balancing */ |
| if (tb->lnum[0]) |
| return balance_leaf_when_delete_left(tb); |
| |
| if (tb->rnum[0] == -1) { |
| /* all contents of R[0] and S[0] will be in R[0] */ |
| leaf_shift_right(tb, n, -1); |
| reiserfs_invalidate_buffer(tb, tbS0); |
| return 0; |
| } |
| |
| RFALSE(tb->rnum[0], |
| "PAP-12065: bad rnum parameter must be 0 (%d)", tb->rnum[0]); |
| return 0; |
| } |
| |
| static unsigned int balance_leaf_insert_left(struct tree_balance *tb, |
| struct item_head *const ih, |
| const char * const body) |
| { |
| int ret; |
| struct buffer_info bi; |
| int n = B_NR_ITEMS(tb->L[0]); |
| unsigned body_shift_bytes = 0; |
| |
| if (tb->item_pos == tb->lnum[0] - 1 && tb->lbytes != -1) { |
| /* part of new item falls into L[0] */ |
| int new_item_len, shift; |
| int version; |
| |
| ret = leaf_shift_left(tb, tb->lnum[0] - 1, -1); |
| |
| /* Calculate item length to insert to S[0] */ |
| new_item_len = ih_item_len(ih) - tb->lbytes; |
| |
| /* Calculate and check item length to insert to L[0] */ |
| put_ih_item_len(ih, ih_item_len(ih) - new_item_len); |
| |
| RFALSE(ih_item_len(ih) <= 0, |
| "PAP-12080: there is nothing to insert into L[0]: " |
| "ih_item_len=%d", ih_item_len(ih)); |
| |
| /* Insert new item into L[0] */ |
| buffer_info_init_left(tb, &bi); |
| leaf_insert_into_buf(&bi, n + tb->item_pos - ret, ih, body, |
| min_t(int, tb->zeroes_num, ih_item_len(ih))); |
| |
| version = ih_version(ih); |
| |
| /* |
| * Calculate key component, item length and body to |
| * insert into S[0] |
| */ |
| shift = 0; |
| if (is_indirect_le_ih(ih)) |
| shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT; |
| |
| add_le_ih_k_offset(ih, tb->lbytes << shift); |
| |
| put_ih_item_len(ih, new_item_len); |
| if (tb->lbytes > tb->zeroes_num) { |
| body_shift_bytes = tb->lbytes - tb->zeroes_num; |
| tb->zeroes_num = 0; |
| } else |
| tb->zeroes_num -= tb->lbytes; |
| |
| RFALSE(ih_item_len(ih) <= 0, |
| "PAP-12085: there is nothing to insert into S[0]: " |
| "ih_item_len=%d", ih_item_len(ih)); |
| } else { |
| /* new item in whole falls into L[0] */ |
| /* Shift lnum[0]-1 items to L[0] */ |
| ret = leaf_shift_left(tb, tb->lnum[0] - 1, tb->lbytes); |
| |
| /* Insert new item into L[0] */ |
| buffer_info_init_left(tb, &bi); |
| leaf_insert_into_buf(&bi, n + tb->item_pos - ret, ih, body, |
| tb->zeroes_num); |
| tb->insert_size[0] = 0; |
| tb->zeroes_num = 0; |
| } |
| return body_shift_bytes; |
| } |
| |
| static void balance_leaf_paste_left_shift_dirent(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body) |
| { |
| int n = B_NR_ITEMS(tb->L[0]); |
| struct buffer_info bi; |
| |
| RFALSE(tb->zeroes_num, |
| "PAP-12090: invalid parameter in case of a directory"); |
| |
| /* directory item */ |
| if (tb->lbytes > tb->pos_in_item) { |
| /* new directory entry falls into L[0] */ |
| struct item_head *pasted; |
| int ret, l_pos_in_item = tb->pos_in_item; |
| |
| /* |
| * Shift lnum[0] - 1 items in whole. |
| * Shift lbytes - 1 entries from given directory item |
| */ |
| ret = leaf_shift_left(tb, tb->lnum[0], tb->lbytes - 1); |
| if (ret && !tb->item_pos) { |
| pasted = item_head(tb->L[0], B_NR_ITEMS(tb->L[0]) - 1); |
| l_pos_in_item += ih_entry_count(pasted) - |
| (tb->lbytes - 1); |
| } |
| |
| /* Append given directory entry to directory item */ |
| buffer_info_init_left(tb, &bi); |
| leaf_paste_in_buffer(&bi, n + tb->item_pos - ret, |
| l_pos_in_item, tb->insert_size[0], |
| body, tb->zeroes_num); |
| |
| /* |
| * previous string prepared space for pasting new entry, |
| * following string pastes this entry |
| */ |
| |
| /* |
| * when we have merge directory item, pos_in_item |
| * has been changed too |
| */ |
| |
| /* paste new directory entry. 1 is entry number */ |
| leaf_paste_entries(&bi, n + tb->item_pos - ret, |
| l_pos_in_item, 1, |
| (struct reiserfs_de_head *) body, |
| body + DEH_SIZE, tb->insert_size[0]); |
| tb->insert_size[0] = 0; |
| } else { |
| /* new directory item doesn't fall into L[0] */ |
| /* |
| * Shift lnum[0]-1 items in whole. Shift lbytes |
| * directory entries from directory item number lnum[0] |
| */ |
| leaf_shift_left(tb, tb->lnum[0], tb->lbytes); |
| } |
| |
| /* Calculate new position to append in item body */ |
| tb->pos_in_item -= tb->lbytes; |
| } |
| |
| static unsigned int balance_leaf_paste_left_shift(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int n = B_NR_ITEMS(tb->L[0]); |
| struct buffer_info bi; |
| int body_shift_bytes = 0; |
| |
| if (is_direntry_le_ih(item_head(tbS0, tb->item_pos))) { |
| balance_leaf_paste_left_shift_dirent(tb, ih, body); |
| return 0; |
| } |
| |
| RFALSE(tb->lbytes <= 0, |
| "PAP-12095: there is nothing to shift to L[0]. " |
| "lbytes=%d", tb->lbytes); |
| RFALSE(tb->pos_in_item != ih_item_len(item_head(tbS0, tb->item_pos)), |
| "PAP-12100: incorrect position to paste: " |
| "item_len=%d, pos_in_item=%d", |
| ih_item_len(item_head(tbS0, tb->item_pos)), tb->pos_in_item); |
| |
| /* appended item will be in L[0] in whole */ |
| if (tb->lbytes >= tb->pos_in_item) { |
| struct item_head *tbS0_pos_ih, *tbL0_ih; |
| struct item_head *tbS0_0_ih; |
| struct reiserfs_key *left_delim_key; |
| int ret, l_n, version, temp_l; |
| |
| tbS0_pos_ih = item_head(tbS0, tb->item_pos); |
| tbS0_0_ih = item_head(tbS0, 0); |
| |
| /* |
| * this bytes number must be appended |
| * to the last item of L[h] |
| */ |
| l_n = tb->lbytes - tb->pos_in_item; |
| |
| /* Calculate new insert_size[0] */ |
| tb->insert_size[0] -= l_n; |
| |
| RFALSE(tb->insert_size[0] <= 0, |
| "PAP-12105: there is nothing to paste into " |
| "L[0]. insert_size=%d", tb->insert_size[0]); |
| |
| ret = leaf_shift_left(tb, tb->lnum[0], |
| ih_item_len(tbS0_pos_ih)); |
| |
| tbL0_ih = item_head(tb->L[0], n + tb->item_pos - ret); |
| |
| /* Append to body of item in L[0] */ |
| buffer_info_init_left(tb, &bi); |
| leaf_paste_in_buffer(&bi, n + tb->item_pos - ret, |
| ih_item_len(tbL0_ih), l_n, body, |
| min_t(int, l_n, tb->zeroes_num)); |
| |
| /* |
| * 0-th item in S0 can be only of DIRECT type |
| * when l_n != 0 |
| */ |
| temp_l = l_n; |
| |
| RFALSE(ih_item_len(tbS0_0_ih), |
| "PAP-12106: item length must be 0"); |
| RFALSE(comp_short_le_keys(&tbS0_0_ih->ih_key, |
| leaf_key(tb->L[0], n + tb->item_pos - ret)), |
| "PAP-12107: items must be of the same file"); |
| |
| if (is_indirect_le_ih(tbL0_ih)) { |
| int shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT; |
| temp_l = l_n << shift; |
| } |
| /* update key of first item in S0 */ |
| version = ih_version(tbS0_0_ih); |
| add_le_key_k_offset(version, &tbS0_0_ih->ih_key, temp_l); |
| |
| /* update left delimiting key */ |
| left_delim_key = internal_key(tb->CFL[0], tb->lkey[0]); |
| add_le_key_k_offset(version, left_delim_key, temp_l); |
| |
| /* |
| * Calculate new body, position in item and |
| * insert_size[0] |
| */ |
| if (l_n > tb->zeroes_num) { |
| body_shift_bytes = l_n - tb->zeroes_num; |
| tb->zeroes_num = 0; |
| } else |
| tb->zeroes_num -= l_n; |
| tb->pos_in_item = 0; |
| |
| RFALSE(comp_short_le_keys(&tbS0_0_ih->ih_key, |
| leaf_key(tb->L[0], |
| B_NR_ITEMS(tb->L[0]) - 1)) || |
| !op_is_left_mergeable(leaf_key(tbS0, 0), tbS0->b_size) || |
| !op_is_left_mergeable(left_delim_key, tbS0->b_size), |
| "PAP-12120: item must be merge-able with left " |
| "neighboring item"); |
| } else { |
| /* only part of the appended item will be in L[0] */ |
| |
| /* Calculate position in item for append in S[0] */ |
| tb->pos_in_item -= tb->lbytes; |
| |
| RFALSE(tb->pos_in_item <= 0, |
| "PAP-12125: no place for paste. pos_in_item=%d", |
| tb->pos_in_item); |
| |
| /* |
| * Shift lnum[0] - 1 items in whole. |
| * Shift lbytes - 1 byte from item number lnum[0] |
| */ |
| leaf_shift_left(tb, tb->lnum[0], tb->lbytes); |
| } |
| return body_shift_bytes; |
| } |
| |
| |
| /* appended item will be in L[0] in whole */ |
| static void balance_leaf_paste_left_whole(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int n = B_NR_ITEMS(tb->L[0]); |
| struct buffer_info bi; |
| struct item_head *pasted; |
| int ret; |
| |
| /* if we paste into first item of S[0] and it is left mergable */ |
| if (!tb->item_pos && |
| op_is_left_mergeable(leaf_key(tbS0, 0), tbS0->b_size)) { |
| /* |
| * then increment pos_in_item by the size of the |
| * last item in L[0] |
| */ |
| pasted = item_head(tb->L[0], n - 1); |
| if (is_direntry_le_ih(pasted)) |
| tb->pos_in_item += ih_entry_count(pasted); |
| else |
| tb->pos_in_item += ih_item_len(pasted); |
| } |
| |
| /* |
| * Shift lnum[0] - 1 items in whole. |
| * Shift lbytes - 1 byte from item number lnum[0] |
| */ |
| ret = leaf_shift_left(tb, tb->lnum[0], tb->lbytes); |
| |
| /* Append to body of item in L[0] */ |
| buffer_info_init_left(tb, &bi); |
| leaf_paste_in_buffer(&bi, n + tb->item_pos - ret, tb->pos_in_item, |
| tb->insert_size[0], body, tb->zeroes_num); |
| |
| /* if appended item is directory, paste entry */ |
| pasted = item_head(tb->L[0], n + tb->item_pos - ret); |
| if (is_direntry_le_ih(pasted)) |
| leaf_paste_entries(&bi, n + tb->item_pos - ret, |
| tb->pos_in_item, 1, |
| (struct reiserfs_de_head *)body, |
| body + DEH_SIZE, tb->insert_size[0]); |
| |
| /* |
| * if appended item is indirect item, put unformatted node |
| * into un list |
| */ |
| if (is_indirect_le_ih(pasted)) |
| set_ih_free_space(pasted, 0); |
| |
| tb->insert_size[0] = 0; |
| tb->zeroes_num = 0; |
| } |
| |
| static unsigned int balance_leaf_paste_left(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body) |
| { |
| /* we must shift the part of the appended item */ |
| if (tb->item_pos == tb->lnum[0] - 1 && tb->lbytes != -1) |
| return balance_leaf_paste_left_shift(tb, ih, body); |
| else |
| balance_leaf_paste_left_whole(tb, ih, body); |
| return 0; |
| } |
| |
| /* Shift lnum[0] items from S[0] to the left neighbor L[0] */ |
| static unsigned int balance_leaf_left(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body, int flag) |
| { |
| if (tb->lnum[0] <= 0) |
| return 0; |
| |
| /* new item or it part falls to L[0], shift it too */ |
| if (tb->item_pos < tb->lnum[0]) { |
| BUG_ON(flag != M_INSERT && flag != M_PASTE); |
| |
| if (flag == M_INSERT) |
| return balance_leaf_insert_left(tb, ih, body); |
| else /* M_PASTE */ |
| return balance_leaf_paste_left(tb, ih, body); |
| } else |
| /* new item doesn't fall into L[0] */ |
| leaf_shift_left(tb, tb->lnum[0], tb->lbytes); |
| return 0; |
| } |
| |
| |
| static void balance_leaf_insert_right(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body) |
| { |
| |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int n = B_NR_ITEMS(tbS0); |
| struct buffer_info bi; |
| int ret; |
| |
| /* new item or part of it doesn't fall into R[0] */ |
| if (n - tb->rnum[0] >= tb->item_pos) { |
| leaf_shift_right(tb, tb->rnum[0], tb->rbytes); |
| return; |
| } |
| |
| /* new item or its part falls to R[0] */ |
| |
| /* part of new item falls into R[0] */ |
| if (tb->item_pos == n - tb->rnum[0] + 1 && tb->rbytes != -1) { |
| loff_t old_key_comp, old_len, r_zeroes_number; |
| const char *r_body; |
| int version, shift; |
| loff_t offset; |
| |
| leaf_shift_right(tb, tb->rnum[0] - 1, -1); |
| |
| version = ih_version(ih); |
| |
| /* Remember key component and item length */ |
| old_key_comp = le_ih_k_offset(ih); |
| old_len = ih_item_len(ih); |
| |
| /* |
| * Calculate key component and item length to insert |
| * into R[0] |
| */ |
| shift = 0; |
| if (is_indirect_le_ih(ih)) |
| shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT; |
| offset = le_ih_k_offset(ih) + ((old_len - tb->rbytes) << shift); |
| set_le_ih_k_offset(ih, offset); |
| put_ih_item_len(ih, tb->rbytes); |
| |
| /* Insert part of the item into R[0] */ |
| buffer_info_init_right(tb, &bi); |
| if ((old_len - tb->rbytes) > tb->zeroes_num) { |
| r_zeroes_number = 0; |
| r_body = body + (old_len - tb->rbytes) - tb->zeroes_num; |
| } else { |
| r_body = body; |
| r_zeroes_number = tb->zeroes_num - |
| (old_len - tb->rbytes); |
| tb->zeroes_num -= r_zeroes_number; |
| } |
| |
| leaf_insert_into_buf(&bi, 0, ih, r_body, r_zeroes_number); |
| |
| /* Replace right delimiting key by first key in R[0] */ |
| replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0); |
| |
| /* |
| * Calculate key component and item length to |
| * insert into S[0] |
| */ |
| set_le_ih_k_offset(ih, old_key_comp); |
| put_ih_item_len(ih, old_len - tb->rbytes); |
| |
| tb->insert_size[0] -= tb->rbytes; |
| |
| } else { |
| /* whole new item falls into R[0] */ |
| |
| /* Shift rnum[0]-1 items to R[0] */ |
| ret = leaf_shift_right(tb, tb->rnum[0] - 1, tb->rbytes); |
| |
| /* Insert new item into R[0] */ |
| buffer_info_init_right(tb, &bi); |
| leaf_insert_into_buf(&bi, tb->item_pos - n + tb->rnum[0] - 1, |
| ih, body, tb->zeroes_num); |
| |
| if (tb->item_pos - n + tb->rnum[0] - 1 == 0) |
| replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0); |
| |
| tb->zeroes_num = tb->insert_size[0] = 0; |
| } |
| } |
| |
| |
| static void balance_leaf_paste_right_shift_dirent(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| struct buffer_info bi; |
| int entry_count; |
| |
| RFALSE(tb->zeroes_num, |
| "PAP-12145: invalid parameter in case of a directory"); |
| entry_count = ih_entry_count(item_head(tbS0, tb->item_pos)); |
| |
| /* new directory entry falls into R[0] */ |
| if (entry_count - tb->rbytes < tb->pos_in_item) { |
| int paste_entry_position; |
| |
| RFALSE(tb->rbytes - 1 >= entry_count || !tb->insert_size[0], |
| "PAP-12150: no enough of entries to shift to R[0]: " |
| "rbytes=%d, entry_count=%d", tb->rbytes, entry_count); |
| |
| /* |
| * Shift rnum[0]-1 items in whole. |
| * Shift rbytes-1 directory entries from directory |
| * item number rnum[0] |
| */ |
| leaf_shift_right(tb, tb->rnum[0], tb->rbytes - 1); |
| |
| /* Paste given directory entry to directory item */ |
| paste_entry_position = tb->pos_in_item - entry_count + |
| tb->rbytes - 1; |
| buffer_info_init_right(tb, &bi); |
| leaf_paste_in_buffer(&bi, 0, paste_entry_position, |
| tb->insert_size[0], body, tb->zeroes_num); |
| |
| /* paste entry */ |
| leaf_paste_entries(&bi, 0, paste_entry_position, 1, |
| (struct reiserfs_de_head *) body, |
| body + DEH_SIZE, tb->insert_size[0]); |
| |
| /* change delimiting keys */ |
| if (paste_entry_position == 0) |
| replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0); |
| |
| tb->insert_size[0] = 0; |
| tb->pos_in_item++; |
| } else { |
| /* new directory entry doesn't fall into R[0] */ |
| leaf_shift_right(tb, tb->rnum[0], tb->rbytes); |
| } |
| } |
| |
| static void balance_leaf_paste_right_shift(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int n_shift, n_rem, r_zeroes_number, version; |
| unsigned long temp_rem; |
| const char *r_body; |
| struct buffer_info bi; |
| |
| /* we append to directory item */ |
| if (is_direntry_le_ih(item_head(tbS0, tb->item_pos))) { |
| balance_leaf_paste_right_shift_dirent(tb, ih, body); |
| return; |
| } |
| |
| /* regular object */ |
| |
| /* |
| * Calculate number of bytes which must be shifted |
| * from appended item |
| */ |
| n_shift = tb->rbytes - tb->insert_size[0]; |
| if (n_shift < 0) |
| n_shift = 0; |
| |
| RFALSE(tb->pos_in_item != ih_item_len(item_head(tbS0, tb->item_pos)), |
| "PAP-12155: invalid position to paste. ih_item_len=%d, " |
| "pos_in_item=%d", tb->pos_in_item, |
| ih_item_len(item_head(tbS0, tb->item_pos))); |
| |
| leaf_shift_right(tb, tb->rnum[0], n_shift); |
| |
| /* |
| * Calculate number of bytes which must remain in body |
| * after appending to R[0] |
| */ |
| n_rem = tb->insert_size[0] - tb->rbytes; |
| if (n_rem < 0) |
| n_rem = 0; |
| |
| temp_rem = n_rem; |
| |
| version = ih_version(item_head(tb->R[0], 0)); |
| |
| if (is_indirect_le_key(version, leaf_key(tb->R[0], 0))) { |
| int shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT; |
| temp_rem = n_rem << shift; |
| } |
| |
| add_le_key_k_offset(version, leaf_key(tb->R[0], 0), temp_rem); |
| add_le_key_k_offset(version, internal_key(tb->CFR[0], tb->rkey[0]), |
| temp_rem); |
| |
| do_balance_mark_internal_dirty(tb, tb->CFR[0], 0); |
| |
| /* Append part of body into R[0] */ |
| buffer_info_init_right(tb, &bi); |
| if (n_rem > tb->zeroes_num) { |
| r_zeroes_number = 0; |
| r_body = body + n_rem - tb->zeroes_num; |
| } else { |
| r_body = body; |
| r_zeroes_number = tb->zeroes_num - n_rem; |
| tb->zeroes_num -= r_zeroes_number; |
| } |
| |
| leaf_paste_in_buffer(&bi, 0, n_shift, tb->insert_size[0] - n_rem, |
| r_body, r_zeroes_number); |
| |
| if (is_indirect_le_ih(item_head(tb->R[0], 0))) |
| set_ih_free_space(item_head(tb->R[0], 0), 0); |
| |
| tb->insert_size[0] = n_rem; |
| if (!n_rem) |
| tb->pos_in_item++; |
| } |
| |
| static void balance_leaf_paste_right_whole(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int n = B_NR_ITEMS(tbS0); |
| struct item_head *pasted; |
| struct buffer_info bi; |
| |
| buffer_info_init_right(tb, &bi); |
| leaf_shift_right(tb, tb->rnum[0], tb->rbytes); |
| |
| /* append item in R[0] */ |
| if (tb->pos_in_item >= 0) { |
| buffer_info_init_right(tb, &bi); |
| leaf_paste_in_buffer(&bi, tb->item_pos - n + tb->rnum[0], |
| tb->pos_in_item, tb->insert_size[0], body, |
| tb->zeroes_num); |
| } |
| |
| /* paste new entry, if item is directory item */ |
| pasted = item_head(tb->R[0], tb->item_pos - n + tb->rnum[0]); |
| if (is_direntry_le_ih(pasted) && tb->pos_in_item >= 0) { |
| leaf_paste_entries(&bi, tb->item_pos - n + tb->rnum[0], |
| tb->pos_in_item, 1, |
| (struct reiserfs_de_head *)body, |
| body + DEH_SIZE, tb->insert_size[0]); |
| |
| if (!tb->pos_in_item) { |
| |
| RFALSE(tb->item_pos - n + tb->rnum[0], |
| "PAP-12165: directory item must be first " |
| "item of node when pasting is in 0th position"); |
| |
| /* update delimiting keys */ |
| replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0); |
| } |
| } |
| |
| if (is_indirect_le_ih(pasted)) |
| set_ih_free_space(pasted, 0); |
| tb->zeroes_num = tb->insert_size[0] = 0; |
| } |
| |
| static void balance_leaf_paste_right(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int n = B_NR_ITEMS(tbS0); |
| |
| /* new item doesn't fall into R[0] */ |
| if (n - tb->rnum[0] > tb->item_pos) { |
| leaf_shift_right(tb, tb->rnum[0], tb->rbytes); |
| return; |
| } |
| |
| /* pasted item or part of it falls to R[0] */ |
| |
| if (tb->item_pos == n - tb->rnum[0] && tb->rbytes != -1) |
| /* we must shift the part of the appended item */ |
| balance_leaf_paste_right_shift(tb, ih, body); |
| else |
| /* pasted item in whole falls into R[0] */ |
| balance_leaf_paste_right_whole(tb, ih, body); |
| } |
| |
| /* shift rnum[0] items from S[0] to the right neighbor R[0] */ |
| static void balance_leaf_right(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body, int flag) |
| { |
| if (tb->rnum[0] <= 0) |
| return; |
| |
| BUG_ON(flag != M_INSERT && flag != M_PASTE); |
| |
| if (flag == M_INSERT) |
| balance_leaf_insert_right(tb, ih, body); |
| else /* M_PASTE */ |
| balance_leaf_paste_right(tb, ih, body); |
| } |
| |
| static void 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) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int n = B_NR_ITEMS(tbS0); |
| struct buffer_info bi; |
| int shift; |
| |
| /* new item or it part don't falls into S_new[i] */ |
| if (n - tb->snum[i] >= tb->item_pos) { |
| leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, |
| tb->snum[i], tb->sbytes[i], tb->S_new[i]); |
| return; |
| } |
| |
| /* new item or it's part falls to first new node S_new[i] */ |
| |
| /* part of new item falls into S_new[i] */ |
| if (tb->item_pos == n - tb->snum[i] + 1 && tb->sbytes[i] != -1) { |
| int old_key_comp, old_len, r_zeroes_number; |
| const char *r_body; |
| int version; |
| |
| /* Move snum[i]-1 items from S[0] to S_new[i] */ |
| leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i] - 1, -1, |
| tb->S_new[i]); |
| |
| /* Remember key component and item length */ |
| version = ih_version(ih); |
| old_key_comp = le_ih_k_offset(ih); |
| old_len = ih_item_len(ih); |
| |
| /* |
| * Calculate key component and item length to insert |
| * into S_new[i] |
| */ |
| shift = 0; |
| if (is_indirect_le_ih(ih)) |
| shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT; |
| set_le_ih_k_offset(ih, |
| le_ih_k_offset(ih) + |
| ((old_len - tb->sbytes[i]) << shift)); |
| |
| put_ih_item_len(ih, tb->sbytes[i]); |
| |
| /* Insert part of the item into S_new[i] before 0-th item */ |
| buffer_info_init_bh(tb, &bi, tb->S_new[i]); |
| |
| if ((old_len - tb->sbytes[i]) > tb->zeroes_num) { |
| r_zeroes_number = 0; |
| r_body = body + (old_len - tb->sbytes[i]) - |
| tb->zeroes_num; |
| } else { |
| r_body = body; |
| r_zeroes_number = tb->zeroes_num - (old_len - |
| tb->sbytes[i]); |
| tb->zeroes_num -= r_zeroes_number; |
| } |
| |
| leaf_insert_into_buf(&bi, 0, ih, r_body, r_zeroes_number); |
| |
| /* |
| * Calculate key component and item length to |
| * insert into S[i] |
| */ |
| set_le_ih_k_offset(ih, old_key_comp); |
| put_ih_item_len(ih, old_len - tb->sbytes[i]); |
| tb->insert_size[0] -= tb->sbytes[i]; |
| } else { |
| /* whole new item falls into S_new[i] */ |
| |
| /* |
| * Shift snum[0] - 1 items to S_new[i] |
| * (sbytes[i] of split item) |
| */ |
| leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, |
| tb->snum[i] - 1, tb->sbytes[i], tb->S_new[i]); |
| |
| /* Insert new item into S_new[i] */ |
| buffer_info_init_bh(tb, &bi, tb->S_new[i]); |
| leaf_insert_into_buf(&bi, tb->item_pos - n + tb->snum[i] - 1, |
| ih, body, tb->zeroes_num); |
| |
| tb->zeroes_num = tb->insert_size[0] = 0; |
| } |
| } |
| |
| /* we append to directory item */ |
| static void 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) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| struct item_head *aux_ih = item_head(tbS0, tb->item_pos); |
| int entry_count = ih_entry_count(aux_ih); |
| struct buffer_info bi; |
| |
| if (entry_count - tb->sbytes[i] < tb->pos_in_item && |
| tb->pos_in_item <= entry_count) { |
| /* new directory entry falls into S_new[i] */ |
| |
| RFALSE(!tb->insert_size[0], |
| "PAP-12215: insert_size is already 0"); |
| RFALSE(tb->sbytes[i] - 1 >= entry_count, |
| "PAP-12220: there are no so much entries (%d), only %d", |
| tb->sbytes[i] - 1, entry_count); |
| |
| /* |
| * Shift snum[i]-1 items in whole. |
| * Shift sbytes[i] directory entries |
| * from directory item number snum[i] |
| */ |
| leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i], |
| tb->sbytes[i] - 1, tb->S_new[i]); |
| |
| /* |
| * Paste given directory entry to |
| * directory item |
| */ |
| buffer_info_init_bh(tb, &bi, tb->S_new[i]); |
| leaf_paste_in_buffer(&bi, 0, tb->pos_in_item - entry_count + |
| tb->sbytes[i] - 1, tb->insert_size[0], |
| body, tb->zeroes_num); |
| |
| /* paste new directory entry */ |
| leaf_paste_entries(&bi, 0, tb->pos_in_item - entry_count + |
| tb->sbytes[i] - 1, 1, |
| (struct reiserfs_de_head *) body, |
| body + DEH_SIZE, tb->insert_size[0]); |
| |
| tb->insert_size[0] = 0; |
| tb->pos_in_item++; |
| } else { |
| /* new directory entry doesn't fall into S_new[i] */ |
| leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i], |
| tb->sbytes[i], tb->S_new[i]); |
| } |
| |
| } |
| |
| static void 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) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| struct item_head *aux_ih = item_head(tbS0, tb->item_pos); |
| int n_shift, n_rem, r_zeroes_number, shift; |
| const char *r_body; |
| struct item_head *tmp; |
| struct buffer_info bi; |
| |
| RFALSE(ih, "PAP-12210: ih must be 0"); |
| |
| if (is_direntry_le_ih(aux_ih)) { |
| balance_leaf_new_nodes_paste_dirent(tb, ih, body, insert_key, |
| insert_ptr, i); |
| return; |
| } |
| |
| /* regular object */ |
| |
| |
| RFALSE(tb->pos_in_item != ih_item_len(item_head(tbS0, tb->item_pos)) || |
| tb->insert_size[0] <= 0, |
| "PAP-12225: item too short or insert_size <= 0"); |
| |
| /* |
| * Calculate number of bytes which must be shifted from appended item |
| */ |
| n_shift = tb->sbytes[i] - tb->insert_size[0]; |
| if (n_shift < 0) |
| n_shift = 0; |
| leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i], n_shift, |
| tb->S_new[i]); |
| |
| /* |
| * Calculate number of bytes which must remain in body after |
| * append to S_new[i] |
| */ |
| n_rem = tb->insert_size[0] - tb->sbytes[i]; |
| if (n_rem < 0) |
| n_rem = 0; |
| |
| /* Append part of body into S_new[0] */ |
| buffer_info_init_bh(tb, &bi, tb->S_new[i]); |
| if (n_rem > tb->zeroes_num) { |
| r_zeroes_number = 0; |
| r_body = body + n_rem - tb->zeroes_num; |
| } else { |
| r_body = body; |
| r_zeroes_number = tb->zeroes_num - n_rem; |
| tb->zeroes_num -= r_zeroes_number; |
| } |
| |
| leaf_paste_in_buffer(&bi, 0, n_shift, tb->insert_size[0] - n_rem, |
| r_body, r_zeroes_number); |
| |
| tmp = item_head(tb->S_new[i], 0); |
| shift = 0; |
| if (is_indirect_le_ih(tmp)) { |
| set_ih_free_space(tmp, 0); |
| shift = tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT; |
| } |
| add_le_ih_k_offset(tmp, n_rem << shift); |
| |
| tb->insert_size[0] = n_rem; |
| if (!n_rem) |
| tb->pos_in_item++; |
| } |
| |
| static void 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) |
| |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int n = B_NR_ITEMS(tbS0); |
| int leaf_mi; |
| struct item_head *pasted; |
| struct buffer_info bi; |
| |
| #ifdef CONFIG_REISERFS_CHECK |
| struct item_head *ih_check = item_head(tbS0, tb->item_pos); |
| |
| if (!is_direntry_le_ih(ih_check) && |
| (tb->pos_in_item != ih_item_len(ih_check) || |
| tb->insert_size[0] <= 0)) |
| reiserfs_panic(tb->tb_sb, |
| "PAP-12235", |
| "pos_in_item must be equal to ih_item_len"); |
| #endif |
| |
| leaf_mi = leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, tb->snum[i], |
| tb->sbytes[i], tb->S_new[i]); |
| |
| RFALSE(leaf_mi, |
| "PAP-12240: unexpected value returned by leaf_move_items (%d)", |
| leaf_mi); |
| |
| /* paste into item */ |
| buffer_info_init_bh(tb, &bi, tb->S_new[i]); |
| leaf_paste_in_buffer(&bi, tb->item_pos - n + tb->snum[i], |
| tb->pos_in_item, tb->insert_size[0], |
| body, tb->zeroes_num); |
| |
| pasted = item_head(tb->S_new[i], tb->item_pos - n + |
| tb->snum[i]); |
| if (is_direntry_le_ih(pasted)) |
| leaf_paste_entries(&bi, tb->item_pos - n + tb->snum[i], |
| tb->pos_in_item, 1, |
| (struct reiserfs_de_head *)body, |
| body + DEH_SIZE, tb->insert_size[0]); |
| |
| /* if we paste to indirect item update ih_free_space */ |
| if (is_indirect_le_ih(pasted)) |
| set_ih_free_space(pasted, 0); |
| |
| tb->zeroes_num = tb->insert_size[0] = 0; |
| |
| } |
| static void 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) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| int n = B_NR_ITEMS(tbS0); |
| |
| /* pasted item doesn't fall into S_new[i] */ |
| if (n - tb->snum[i] > tb->item_pos) { |
| leaf_move_items(LEAF_FROM_S_TO_SNEW, tb, |
| tb->snum[i], tb->sbytes[i], tb->S_new[i]); |
| return; |
| } |
| |
| /* pasted item or part if it falls to S_new[i] */ |
| |
| if (tb->item_pos == n - tb->snum[i] && tb->sbytes[i] != -1) |
| /* we must shift part of the appended item */ |
| balance_leaf_new_nodes_paste_shift(tb, ih, body, insert_key, |
| insert_ptr, i); |
| else |
| /* item falls wholly into S_new[i] */ |
| balance_leaf_new_nodes_paste_whole(tb, ih, body, insert_key, |
| insert_ptr, i); |
| } |
| |
| /* Fill new nodes that appear in place of S[0] */ |
| static void 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) |
| { |
| int i; |
| for (i = tb->blknum[0] - 2; i >= 0; i--) { |
| BUG_ON(flag != M_INSERT && flag != M_PASTE); |
| |
| RFALSE(!tb->snum[i], |
| "PAP-12200: snum[%d] == %d. Must be > 0", i, |
| tb->snum[i]); |
| |
| /* here we shift from S to S_new nodes */ |
| |
| tb->S_new[i] = get_FEB(tb); |
| |
| /* initialized block type and tree level */ |
| set_blkh_level(B_BLK_HEAD(tb->S_new[i]), DISK_LEAF_NODE_LEVEL); |
| |
| if (flag == M_INSERT) |
| balance_leaf_new_nodes_insert(tb, ih, body, insert_key, |
| insert_ptr, i); |
| else /* M_PASTE */ |
| balance_leaf_new_nodes_paste(tb, ih, body, insert_key, |
| insert_ptr, i); |
| |
| memcpy(insert_key + i, leaf_key(tb->S_new[i], 0), KEY_SIZE); |
| insert_ptr[i] = tb->S_new[i]; |
| |
| RFALSE(!buffer_journaled(tb->S_new[i]) |
| || buffer_journal_dirty(tb->S_new[i]) |
| || buffer_dirty(tb->S_new[i]), |
| "PAP-12247: S_new[%d] : (%b)", |
| i, tb->S_new[i]); |
| } |
| } |
| |
| static void balance_leaf_finish_node_insert(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| struct buffer_info bi; |
| buffer_info_init_tbS0(tb, &bi); |
| leaf_insert_into_buf(&bi, tb->item_pos, ih, body, tb->zeroes_num); |
| |
| /* If we insert the first key change the delimiting key */ |
| if (tb->item_pos == 0) { |
| if (tb->CFL[0]) /* can be 0 in reiserfsck */ |
| replace_key(tb, tb->CFL[0], tb->lkey[0], tbS0, 0); |
| |
| } |
| } |
| |
| static void balance_leaf_finish_node_paste_dirent(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| struct item_head *pasted = item_head(tbS0, tb->item_pos); |
| struct buffer_info bi; |
| |
| if (tb->pos_in_item >= 0 && tb->pos_in_item <= ih_entry_count(pasted)) { |
| RFALSE(!tb->insert_size[0], |
| "PAP-12260: insert_size is 0 already"); |
| |
| /* prepare space */ |
| buffer_info_init_tbS0(tb, &bi); |
| leaf_paste_in_buffer(&bi, tb->item_pos, tb->pos_in_item, |
| tb->insert_size[0], body, tb->zeroes_num); |
| |
| /* paste entry */ |
| leaf_paste_entries(&bi, tb->item_pos, tb->pos_in_item, 1, |
| (struct reiserfs_de_head *)body, |
| body + DEH_SIZE, tb->insert_size[0]); |
| |
| if (!tb->item_pos && !tb->pos_in_item) { |
| RFALSE(!tb->CFL[0] || !tb->L[0], |
| "PAP-12270: CFL[0]/L[0] must be specified"); |
| if (tb->CFL[0]) |
| replace_key(tb, tb->CFL[0], tb->lkey[0], |
| tbS0, 0); |
| } |
| |
| tb->insert_size[0] = 0; |
| } |
| } |
| |
| static void balance_leaf_finish_node_paste(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| struct buffer_info bi; |
| struct item_head *pasted = item_head(tbS0, tb->item_pos); |
| |
| /* when directory, may be new entry already pasted */ |
| if (is_direntry_le_ih(pasted)) { |
| balance_leaf_finish_node_paste_dirent(tb, ih, body); |
| return; |
| } |
| |
| /* regular object */ |
| |
| if (tb->pos_in_item == ih_item_len(pasted)) { |
| RFALSE(tb->insert_size[0] <= 0, |
| "PAP-12275: insert size must not be %d", |
| tb->insert_size[0]); |
| buffer_info_init_tbS0(tb, &bi); |
| leaf_paste_in_buffer(&bi, tb->item_pos, |
| tb->pos_in_item, tb->insert_size[0], body, |
| tb->zeroes_num); |
| |
| if (is_indirect_le_ih(pasted)) |
| set_ih_free_space(pasted, 0); |
| |
| tb->insert_size[0] = 0; |
| } |
| #ifdef CONFIG_REISERFS_CHECK |
| else if (tb->insert_size[0]) { |
| print_cur_tb("12285"); |
| reiserfs_panic(tb->tb_sb, "PAP-12285", |
| "insert_size must be 0 (%d)", tb->insert_size[0]); |
| } |
| #endif |
| } |
| |
| /* |
| * if the affected item was not wholly shifted then we |
| * perform all necessary operations on that part or whole |
| * of the affected item which remains in S |
| */ |
| static void balance_leaf_finish_node(struct tree_balance *tb, |
| struct item_head * const ih, |
| const char * const body, int flag) |
| { |
| /* if we must insert or append into buffer S[0] */ |
| if (0 <= tb->item_pos && tb->item_pos < tb->s0num) { |
| if (flag == M_INSERT) |
| balance_leaf_finish_node_insert(tb, ih, body); |
| else /* M_PASTE */ |
| balance_leaf_finish_node_paste(tb, ih, body); |
| } |
| } |
| |
| /** |
| * balance_leaf - reiserfs tree balancing algorithm |
| * @tb: tree balance state |
| * @ih: item header of inserted item (little endian) |
| * @body: body of inserted item or bytes to paste |
| * @flag: i - insert, d - delete, c - cut, p - paste (see do_balance) |
| * passed back: |
| * @insert_key: key to insert new nodes |
| * @insert_ptr: array of nodes to insert at the next level |
| * |
| * In our processing of one level we sometimes determine what must be |
| * inserted into the next higher level. This insertion consists of a |
| * key or two keys and their corresponding pointers. |
| */ |
| static int 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) |
| { |
| struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path); |
| |
| PROC_INFO_INC(tb->tb_sb, balance_at[0]); |
| |
| /* Make balance in case insert_size[0] < 0 */ |
| if (tb->insert_size[0] < 0) |
| return balance_leaf_when_delete(tb, flag); |
| |
| tb->item_pos = PATH_LAST_POSITION(tb->tb_path), |
| tb->pos_in_item = tb->tb_path->pos_in_item, |
| tb->zeroes_num = 0; |
| if (flag == M_INSERT && !body) |
| tb->zeroes_num = ih_item_len(ih); |
| |
| /* |
| * for indirect item pos_in_item is measured in unformatted node |
| * pointers. Recalculate to bytes |
| */ |
| if (flag != M_INSERT |
| && is_indirect_le_ih(item_head(tbS0, tb->item_pos))) |
| tb->pos_in_item *= UNFM_P_SIZE; |
| |
| body += balance_leaf_left(tb, ih, body, flag); |
| |
| /* tb->lnum[0] > 0 */ |
| /* Calculate new item position */ |
| tb->item_pos -= (tb->lnum[0] - ((tb->lbytes != -1) ? 1 : 0)); |
| |
| balance_leaf_right(tb, ih, body, flag); |
| |
| /* tb->rnum[0] > 0 */ |
| RFALSE(tb->blknum[0] > 3, |
| "PAP-12180: blknum can not be %d. It must be <= 3", tb->blknum[0]); |
| RFALSE(tb->blknum[0] < 0, |
| "PAP-12185: blknum can not be %d. It must be >= 0", tb->blknum[0]); |
| |
| /* |
| * if while adding to a node we discover that it is possible to split |
| * it in two, and merge the left part into the left neighbor and the |
| * right part into the right neighbor, eliminating the node |
| */ |
| if (tb->blknum[0] == 0) { /* node S[0] is empty now */ |
| |
| RFALSE(!tb->lnum[0] || !tb->rnum[0], |
| "PAP-12190: lnum and rnum must not be zero"); |
| /* |
| * if insertion was done before 0-th position in R[0], right |
| * delimiting key of the tb->L[0]'s and left delimiting key are |
| * not set correctly |
| */ |
| if (tb->CFL[0]) { |
| if (!tb->CFR[0]) |
| reiserfs_panic(tb->tb_sb, "vs-12195", |
| "CFR not initialized"); |
| copy_key(internal_key(tb->CFL[0], tb->lkey[0]), |
| internal_key(tb->CFR[0], tb->rkey[0])); |
| do_balance_mark_internal_dirty(tb, tb->CFL[0], 0); |
| } |
| |
| reiserfs_invalidate_buffer(tb, tbS0); |
| return 0; |
| } |
| |
| balance_leaf_new_nodes(tb, ih, body, insert_key, insert_ptr, flag); |
| |
| balance_leaf_finish_node(tb, ih, body, flag); |
| |
| #ifdef CONFIG_REISERFS_CHECK |
| if (flag == M_PASTE && tb->insert_size[0]) { |
| print_cur_tb("12290"); |
| reiserfs_panic(tb->tb_sb, |
| "PAP-12290", "insert_size is still not 0 (%d)", |
| tb->insert_size[0]); |
| } |
| #endif |
| |
| /* Leaf level of the tree is balanced (end of balance_leaf) */ |
| return 0; |
| } |
| |
| /* Make empty node */ |
| void make_empty_node(struct buffer_info *bi) |
| { |
| struct block_head *blkh; |
| |
| RFALSE(bi->bi_bh == NULL, "PAP-12295: pointer to the buffer is NULL"); |
| |
| blkh = B_BLK_HEAD(bi->bi_bh); |
| set_blkh_nr_item(blkh, 0); |
| set_blkh_free_space(blkh, MAX_CHILD_SIZE(bi->bi_bh)); |
| |
| if (bi->bi_parent) |
| B_N_CHILD(bi->bi_parent, bi->bi_position)->dc_size = 0; /* Endian safe if 0 */ |
| } |
| |
| /* Get first empty buffer */ |
| struct buffer_head *get_FEB(struct tree_balance *tb) |
| { |
| int i; |
| struct buffer_info bi; |
| |
| for (i = 0; i < MAX_FEB_SIZE; i++) |
| if (tb->FEB[i] != NULL) |
| break; |
| |
| if (i == MAX_FEB_SIZE) |
| reiserfs_panic(tb->tb_sb, "vs-12300", "FEB list is empty"); |
| |
| buffer_info_init_bh(tb, &bi, tb->FEB[i]); |
| make_empty_node(&bi); |
| set_buffer_uptodate(tb->FEB[i]); |
| tb->used[i] = tb->FEB[i]; |
| tb->FEB[i] = NULL; |
| |
| return tb->used[i]; |
| } |
| |
| /* This is now used because reiserfs_free_block has to be able to schedule. */ |
| static void store_thrown(struct tree_balance *tb, struct buffer_head *bh) |
| { |
| int i; |
| |
| if (buffer_dirty(bh)) |
| reiserfs_warning(tb->tb_sb, "reiserfs-12320", |
| "called with dirty buffer"); |
| for (i = 0; i < ARRAY_SIZE(tb->thrown); i++) |
| if (!tb->thrown[i]) { |
| tb->thrown[i] = bh; |
| get_bh(bh); /* free_thrown puts this */ |
| return; |
| } |
| reiserfs_warning(tb->tb_sb, "reiserfs-12321", |
| "too many thrown buffers"); |
| } |
| |
| static void free_thrown(struct tree_balance *tb) |
| { |
| int i; |
| b_blocknr_t blocknr; |
| for (i = 0; i < ARRAY_SIZE(tb->thrown); i++) { |
| if (tb->thrown[i]) { |
| blocknr = tb->thrown[i]->b_blocknr; |
| if (buffer_dirty(tb->thrown[i])) |
| reiserfs_warning(tb->tb_sb, "reiserfs-12322", |
| "called with dirty buffer %d", |
| blocknr); |
| brelse(tb->thrown[i]); /* incremented in store_thrown */ |
| reiserfs_free_block(tb->transaction_handle, NULL, |
| blocknr, 0); |
| } |
| } |
| } |
| |
| void reiserfs_invalidate_buffer(struct tree_balance *tb, struct buffer_head *bh) |
| { |
| struct block_head *blkh; |
| blkh = B_BLK_HEAD(bh); |
| set_blkh_level(blkh, FREE_LEVEL); |
| set_blkh_nr_item(blkh, 0); |
| |
| clear_buffer_dirty(bh); |
| store_thrown(tb, bh); |
| } |
| |
| /* Replace n_dest'th key in buffer dest by n_src'th key of buffer src.*/ |
| void replace_key(struct tree_balance *tb, struct buffer_head *dest, int n_dest, |
| struct buffer_head *src, int n_src) |
| { |
| |
| RFALSE(dest == NULL || src == NULL, |
| "vs-12305: source or destination buffer is 0 (src=%p, dest=%p)", |
| src, dest); |
| RFALSE(!B_IS_KEYS_LEVEL(dest), |
| "vs-12310: invalid level (%z) for destination buffer. dest must be leaf", |
| dest); |
| RFALSE(n_dest < 0 || n_src < 0, |
| "vs-12315: src(%d) or dest(%d) key number < 0", n_src, n_dest); |
| RFALSE(n_dest >= B_NR_ITEMS(dest) || n_src >= B_NR_ITEMS(src), |
| "vs-12320: src(%d(%d)) or dest(%d(%d)) key number is too big", |
| n_src, B_NR_ITEMS(src), n_dest, B_NR_ITEMS(dest)); |
| |
| if (B_IS_ITEMS_LEVEL(src)) |
| /* source buffer contains leaf node */ |
| memcpy(internal_key(dest, n_dest), item_head(src, n_src), |
| KEY_SIZE); |
| else |
| memcpy(internal_key(dest, n_dest), internal_key(src, n_src), |
| KEY_SIZE); |
| |
| do_balance_mark_internal_dirty(tb, dest, 0); |
| } |
| |
| int get_left_neighbor_position(struct tree_balance *tb, int h) |
| { |
| int Sh_position = PATH_H_POSITION(tb->tb_path, h + 1); |
| |
| RFALSE(PATH_H_PPARENT(tb->tb_path, h) == NULL || tb->FL[h] == NULL, |
| "vs-12325: FL[%d](%p) or F[%d](%p) does not exist", |
| h, tb->FL[h], h, PATH_H_PPARENT(tb->tb_path, h)); |
| |
| if (Sh_position == 0) |
| return B_NR_ITEMS(tb->FL[h]); |
| else |
| return Sh_position - 1; |
| } |
| |
| int get_right_neighbor_position(struct tree_balance *tb, int h) |
| { |
| int Sh_position = PATH_H_POSITION(tb->tb_path, h + 1); |
| |
| RFALSE(PATH_H_PPARENT(tb->tb_path, h) == NULL || tb->FR[h] == NULL, |
| "vs-12330: F[%d](%p) or FR[%d](%p) does not exist", |
| h, PATH_H_PPARENT(tb->tb_path, h), h, tb->FR[h]); |
| |
| if (Sh_position == B_NR_ITEMS(PATH_H_PPARENT(tb->tb_path, h))) |
| return 0; |
| else |
| return Sh_position + 1; |
| } |
| |
| #ifdef CONFIG_REISERFS_CHECK |
| |
| int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value); |
| static void check_internal_node(struct super_block *s, struct buffer_head *bh, |
| char *mes) |
| { |
| struct disk_child *dc; |
| int i; |
| |
| RFALSE(!bh, "PAP-12336: bh == 0"); |
| |
| if (!bh || !B_IS_IN_TREE(bh)) |
| return; |
| |
| RFALSE(!buffer_dirty(bh) && |
| !(buffer_journaled(bh) || buffer_journal_dirty(bh)), |
| "PAP-12337: buffer (%b) must be dirty", bh); |
| dc = B_N_CHILD(bh, 0); |
| |
| for (i = 0; i <= B_NR_ITEMS(bh); i++, dc++) { |
| if (!is_reusable(s, dc_block_number(dc), 1)) { |
| print_cur_tb(mes); |
| reiserfs_panic(s, "PAP-12338", |
| "invalid child pointer %y in %b", |
| dc, bh); |
| } |
| } |
| } |
| |
| static int locked_or_not_in_tree(struct tree_balance *tb, |
| struct buffer_head *bh, char *which) |
| { |
| if ((!buffer_journal_prepared(bh) && buffer_locked(bh)) || |
| !B_IS_IN_TREE(bh)) { |
| reiserfs_warning(tb->tb_sb, "vs-12339", "%s (%b)", which, bh); |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int check_before_balancing(struct tree_balance *tb) |
| { |
| int retval = 0; |
| |
| if (REISERFS_SB(tb->tb_sb)->cur_tb) { |
| reiserfs_panic(tb->tb_sb, "vs-12335", "suspect that schedule " |
| "occurred based on cur_tb not being null at " |
| "this point in code. do_balance cannot properly " |
| "handle concurrent tree accesses on a same " |
| "mount point."); |
| } |
| |
| /* |
| * double check that buffers that we will modify are unlocked. |
| * (fix_nodes should already have prepped all of these for us). |
| */ |
| if (tb->lnum[0]) { |
| retval |= locked_or_not_in_tree(tb, tb->L[0], "L[0]"); |
| retval |= locked_or_not_in_tree(tb, tb->FL[0], "FL[0]"); |
| retval |= locked_or_not_in_tree(tb, tb->CFL[0], "CFL[0]"); |
| check_leaf(tb->L[0]); |
| } |
| if (tb->rnum[0]) { |
| retval |= locked_or_not_in_tree(tb, tb->R[0], "R[0]"); |
| retval |= locked_or_not_in_tree(tb, tb->FR[0], "FR[0]"); |
| retval |= locked_or_not_in_tree(tb, tb->CFR[0], "CFR[0]"); |
| check_leaf(tb->R[0]); |
| } |
| retval |= locked_or_not_in_tree(tb, PATH_PLAST_BUFFER(tb->tb_path), |
| "S[0]"); |
| check_leaf(PATH_PLAST_BUFFER(tb->tb_path)); |
| |
| return retval; |
| } |
| |
| static void check_after_balance_leaf(struct tree_balance *tb) |
| { |
| if (tb->lnum[0]) { |
| if (B_FREE_SPACE(tb->L[0]) != |
| MAX_CHILD_SIZE(tb->L[0]) - |
| dc_size(B_N_CHILD |
| (tb->FL[0], get_left_neighbor_position(tb, 0)))) { |
| print_cur_tb("12221"); |
| reiserfs_panic(tb->tb_sb, "PAP-12355", |
| "shift to left was incorrect"); |
| } |
| } |
| if (tb->rnum[0]) { |
| if (B_FREE_SPACE(tb->R[0]) != |
| MAX_CHILD_SIZE(tb->R[0]) - |
| dc_size(B_N_CHILD |
| (tb->FR[0], get_right_neighbor_position(tb, 0)))) { |
| print_cur_tb("12222"); |
| reiserfs_panic(tb->tb_sb, "PAP-12360", |
| "shift to right was incorrect"); |
| } |
| } |
| if (PATH_H_PBUFFER(tb->tb_path, 1) && |
| (B_FREE_SPACE(PATH_H_PBUFFER(tb->tb_path, 0)) != |
| (MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)) - |
| dc_size(B_N_CHILD(PATH_H_PBUFFER(tb->tb_path, 1), |
| PATH_H_POSITION(tb->tb_path, 1)))))) { |
| int left = B_FREE_SPACE(PATH_H_PBUFFER(tb->tb_path, 0)); |
| int right = (MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)) - |
| dc_size(B_N_CHILD(PATH_H_PBUFFER(tb->tb_path, 1), |
| PATH_H_POSITION(tb->tb_path, |
| 1)))); |
| print_cur_tb("12223"); |
| reiserfs_warning(tb->tb_sb, "reiserfs-12363", |
| "B_FREE_SPACE (PATH_H_PBUFFER(tb->tb_path,0)) = %d; " |
| "MAX_CHILD_SIZE (%d) - dc_size( %y, %d ) [%d] = %d", |
| left, |
| MAX_CHILD_SIZE(PATH_H_PBUFFER(tb->tb_path, 0)), |
| PATH_H_PBUFFER(tb->tb_path, 1), |
| PATH_H_POSITION(tb->tb_path, 1), |
| dc_size(B_N_CHILD |
| (PATH_H_PBUFFER(tb->tb_path, 1), |
| PATH_H_POSITION(tb->tb_path, 1))), |
| right); |
| reiserfs_panic(tb->tb_sb, "PAP-12365", "S is incorrect"); |
| } |
| } |
| |
| static void check_leaf_level(struct tree_balance *tb) |
| { |
| check_leaf(tb->L[0]); |
| check_leaf(tb->R[0]); |
| check_leaf(PATH_PLAST_BUFFER(tb->tb_path)); |
| } |
| |
| static void check_internal_levels(struct tree_balance *tb) |
| { |
| int h; |
| |
| /* check all internal nodes */ |
| for (h = 1; tb->insert_size[h]; h++) { |
| check_internal_node(tb->tb_sb, PATH_H_PBUFFER(tb->tb_path, h), |
| "BAD BUFFER ON PATH"); |
| if (tb->lnum[h]) |
| check_internal_node(tb->tb_sb, tb->L[h], "BAD L"); |
| if (tb->rnum[h]) |
| check_internal_node(tb->tb_sb, tb->R[h], "BAD R"); |
| } |
| |
| } |
| |
| #endif |
| |
| /* |
| * Now we have all of the buffers that must be used in balancing of |
| * the tree. We rely on the assumption that schedule() will not occur |
| * while do_balance works. ( Only interrupt handlers are acceptable.) |
| * We balance the tree according to the analysis made before this, |
| * using buffers already obtained. For SMP support it will someday be |
| * necessary to add ordered locking of tb. |
| */ |
| |
| /* |
| * Some interesting rules of balancing: |
| * we delete a maximum of two nodes per level per balancing: we never |
| * delete R, when we delete two of three nodes L, S, R then we move |
| * them into R. |
| * |
| * we only delete L if we are deleting two nodes, if we delete only |
| * one node we delete S |
| * |
| * if we shift leaves then we shift as much as we can: this is a |
| * deliberate policy of extremism in node packing which results in |
| * higher average utilization after repeated random balance operations |
| * at the cost of more memory copies and more balancing as a result of |
| * small insertions to full nodes. |
| * |
| * if we shift internal nodes we try to evenly balance the node |
| * utilization, with consequent less balancing at the cost of lower |
| * utilization. |
| * |
| * one could argue that the policy for directories in leaves should be |
| * that of internal nodes, but we will wait until another day to |
| * evaluate this.... It would be nice to someday measure and prove |
| * these assumptions as to what is optimal.... |
| */ |
| |
| static inline void do_balance_starts(struct tree_balance *tb) |
| { |
| /* use print_cur_tb() to see initial state of struct tree_balance */ |
| |
| /* store_print_tb (tb); */ |
| |
| /* do not delete, just comment it out */ |
| /* |
| print_tb(flag, PATH_LAST_POSITION(tb->tb_path), |
| tb->tb_path->pos_in_item, tb, "check"); |
| */ |
| RFALSE(check_before_balancing(tb), "PAP-12340: locked buffers in TB"); |
| #ifdef CONFIG_REISERFS_CHECK |
| REISERFS_SB(tb->tb_sb)->cur_tb = tb; |
| #endif |
| } |
| |
| static inline void do_balance_completed(struct tree_balance *tb) |
| { |
| |
| #ifdef CONFIG_REISERFS_CHECK |
| check_leaf_level(tb); |
| check_internal_levels(tb); |
| REISERFS_SB(tb->tb_sb)->cur_tb = NULL; |
| #endif |
| |
| /* |
| * reiserfs_free_block is no longer schedule safe. So, we need to |
| * put the buffers we want freed on the thrown list during do_balance, |
| * and then free them now |
| */ |
| |
| REISERFS_SB(tb->tb_sb)->s_do_balance++; |
| |
| /* release all nodes hold to perform the balancing */ |
| unfix_nodes(tb); |
| |
| free_thrown(tb); |
| } |
| |
| /* |
| * do_balance - balance the tree |
| * |
| * @tb: tree_balance structure |
| * @ih: item header of inserted item |
| * @body: body of inserted item or bytes to paste |
| * @flag: 'i' - insert, 'd' - delete, 'c' - cut, 'p' paste |
| * |
| * Cut means delete part of an item (includes removing an entry from a |
| * directory). |
| * |
| * Delete means delete whole item. |
| * |
| * Insert means add a new item into the tree. |
| * |
| * Paste means to append to the end of an existing file or to |
| * insert a directory entry. |
| */ |
| void do_balance(struct tree_balance *tb, struct item_head *ih, |
| const char *body, int flag) |
| { |
| int child_pos; /* position of a child node in its parent */ |
| int h; /* level of the tree being processed */ |
| |
| /* |
| * in our processing of one level we sometimes determine what |
| * must be inserted into the next higher level. This insertion |
| * consists of a key or two keys and their corresponding |
| * pointers |
| */ |
| struct item_head insert_key[2]; |
| |
| /* inserted node-ptrs for the next level */ |
| struct buffer_head *insert_ptr[2]; |
| |
| tb->tb_mode = flag; |
| tb->need_balance_dirty = 0; |
| |
| if (FILESYSTEM_CHANGED_TB(tb)) { |
| reiserfs_panic(tb->tb_sb, "clm-6000", "fs generation has " |
| "changed"); |
| } |
| /* if we have no real work to do */ |
| if (!tb->insert_size[0]) { |
| reiserfs_warning(tb->tb_sb, "PAP-12350", |
| "insert_size == 0, mode == %c", flag); |
| unfix_nodes(tb); |
| return; |
| } |
| |
| atomic_inc(&fs_generation(tb->tb_sb)); |
| do_balance_starts(tb); |
| |
| /* |
| * balance_leaf returns 0 except if combining L R and S into |
| * one node. see balance_internal() for explanation of this |
| * line of code. |
| */ |
| child_pos = PATH_H_B_ITEM_ORDER(tb->tb_path, 0) + |
| balance_leaf(tb, ih, body, flag, insert_key, insert_ptr); |
| |
| #ifdef CONFIG_REISERFS_CHECK |
| check_after_balance_leaf(tb); |
| #endif |
| |
| /* Balance internal level of the tree. */ |
| for (h = 1; h < MAX_HEIGHT && tb->insert_size[h]; h++) |
| child_pos = balance_internal(tb, h, child_pos, insert_key, |
| insert_ptr); |
| |
| do_balance_completed(tb); |
| } |