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47cff7274856753098786e4fc224d0276bbc903c
reiserfsprogs/reiserfscore/ibalance.c
T
Jeff Mahoney 47cff72748 cleanup: run indent with the Linux Kernel style across all code 
Over the years, the reiserfs kernel code has been gradually cleaned up
to be more readable. This patch does the same to the progs code.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
2013-08-26 17:14:42 -04:00

947 lines
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/*
* Copyright 1996-2004 by Hans Reiser, licensing governed by
* reiserfsprogs/README
*/
#include "includes.h"
/* modes of internal_shift_left, internal_shift_right and internal_insert_childs */
#define INTERNAL_SHIFT_FROM_S_TO_L 0
#define INTERNAL_SHIFT_FROM_R_TO_S 1
#define INTERNAL_SHIFT_FROM_L_TO_S 2
#define INTERNAL_SHIFT_FROM_S_TO_R 3
#define INTERNAL_INSERT_TO_S 4
#define INTERNAL_INSERT_TO_L 5
#define INTERNAL_INSERT_TO_R 6
static void internal_define_dest_src_infos(int shift_mode,
struct tree_balance *tb,
int h,
struct buffer_info *dest_bi,
struct buffer_info *src_bi,
int *d_key, struct buffer_head **cf)
{
/* define dest, src, dest parent, dest position */
switch (shift_mode) {
case INTERNAL_SHIFT_FROM_S_TO_L: /* used in internal_shift_left */
src_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
src_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
dest_bi->bi_bh = tb->L[h];
dest_bi->bi_parent = tb->FL[h];
dest_bi->bi_position = get_left_neighbor_position(tb, h);
*d_key = tb->lkey[h];
*cf = tb->CFL[h];
break;
case INTERNAL_SHIFT_FROM_L_TO_S:
src_bi->bi_bh = tb->L[h];
src_bi->bi_parent = tb->FL[h];
src_bi->bi_position = get_left_neighbor_position(tb, h);
dest_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
dest_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
dest_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1); /* dest position is analog of dest->b_item_order */
*d_key = tb->lkey[h];
*cf = tb->CFL[h];
break;
case INTERNAL_SHIFT_FROM_R_TO_S: /* used in internal_shift_left */
src_bi->bi_bh = tb->R[h];
src_bi->bi_parent = tb->FR[h];
src_bi->bi_position = get_right_neighbor_position(tb, h);
dest_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
dest_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
dest_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
*d_key = tb->rkey[h];
*cf = tb->CFR[h];
break;
case INTERNAL_SHIFT_FROM_S_TO_R:
src_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
src_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
dest_bi->bi_bh = tb->R[h];
dest_bi->bi_parent = tb->FR[h];
dest_bi->bi_position = get_right_neighbor_position(tb, h);
*d_key = tb->rkey[h];
*cf = tb->CFR[h];
break;
case INTERNAL_INSERT_TO_L:
dest_bi->bi_bh = tb->L[h];
dest_bi->bi_parent = tb->FL[h];
dest_bi->bi_position = get_left_neighbor_position(tb, h);
break;
case INTERNAL_INSERT_TO_S:
dest_bi->bi_bh = PATH_H_PBUFFER(tb->tb_path, h);
dest_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, h);
dest_bi->bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
break;
case INTERNAL_INSERT_TO_R:
dest_bi->bi_bh = tb->R[h];
dest_bi->bi_parent = tb->FR[h];
dest_bi->bi_position = get_right_neighbor_position(tb, h);
break;
default:
reiserfs_panic("internal_define_dest_src_infos",
"shift type is unknown (%d)", shift_mode);
}
}
/* Insert 'count' node pointers into buffer cur before position 'to' + 1.
* Insert count items into buffer cur before position to.
* Items and node pointers are specified by inserted and bh respectively.
*/
static void internal_insert_childs(reiserfs_filsys_t *fs,
struct buffer_info *cur_bi,
int to, int count,
struct item_head *inserted,
struct buffer_head **bh)
{
struct buffer_head *cur = cur_bi->bi_bh;
struct block_head *blkh;
int nr;
struct reiserfs_key *key;
struct disk_child new_dc[2];
struct disk_child *dc;
int i;
int from;
if (count <= 0)
return;
blkh = B_BLK_HEAD(cur);
nr = get_blkh_nr_items(blkh);
/* prepare space for count disk_child */
dc = B_N_CHILD(cur, to + 1);
memmove(dc + count, dc, (nr + 1 - (to + 1)) * DC_SIZE);
/* make disk child array for insertion */
for (i = 0; i < count; i++) {
set_dc(new_dc + i, MAX_CHILD_SIZE(bh[i]->b_size) -
get_blkh_free_space(B_BLK_HEAD(bh[i])),
bh[i]->b_blocknr);
/*
set_dc_child_size (new_dc + i,
MAX_CHILD_SIZE(bh[i]->b_size) -
get_blkh_free_space (B_BLK_HEAD (bh[i])));
set_dc_child_blocknr (new_dc + i, bh[i]->b_blocknr); */
}
memcpy(dc, new_dc, DC_SIZE * count);
/* prepare space for 'count' items */
from = ((to == -1) ? 0 : to);
key = B_N_PDELIM_KEY(cur, from);
memmove(key + count, key,
(nr - from /*to */ ) * KEY_SIZE + (nr + 1 + count) * DC_SIZE);
/* copy keys */
memcpy(key, inserted, KEY_SIZE);
if (count > 1)
memcpy(key + 1, inserted + 1, KEY_SIZE);
/* sizes, item number */
set_blkh_nr_items(blkh, nr + count);
set_blkh_free_space(blkh,
get_blkh_free_space(blkh) - count * (DC_SIZE +
KEY_SIZE));
mark_buffer_dirty(cur);
if (cur_bi->bi_parent) {
dc = B_N_CHILD(cur_bi->bi_parent, cur_bi->bi_position);
set_dc_child_size(dc,
get_dc_child_size(dc) + count * (DC_SIZE +
KEY_SIZE));
mark_buffer_dirty(cur_bi->bi_parent);
}
}
/* Delete del_num items and node pointers from buffer cur starting from *
* the first_i'th item and first_p'th pointers respectively. */
static void internal_delete_pointers_items(reiserfs_filsys_t *fs,
struct buffer_info *cur_bi,
int first_p, int first_i,
int del_num)
{
struct buffer_head *cur = cur_bi->bi_bh;
int nr;
struct block_head *blkh;
struct reiserfs_key *key;
struct disk_child *dc;
if (del_num == 0)
return;
blkh = B_BLK_HEAD(cur);
nr = get_blkh_nr_items(blkh);
if (first_p == 0 && del_num == nr + 1) {
make_empty_node(cur_bi);
return;
}
/* deleting */
dc = B_N_CHILD(cur, first_p);
memmove(dc, dc + del_num, (nr + 1 - first_p - del_num) * DC_SIZE);
key = B_N_PDELIM_KEY(cur, first_i);
memmove(key, key + del_num,
(nr - first_i - del_num) * KEY_SIZE + (nr + 1 -
del_num) * DC_SIZE);
/* sizes, item number */
set_blkh_nr_items(blkh, get_blkh_nr_items(blkh) - del_num);
set_blkh_free_space(blkh, get_blkh_free_space(blkh) +
del_num * (KEY_SIZE + DC_SIZE));
mark_buffer_dirty(cur);
if (cur_bi->bi_parent) {
dc = B_N_CHILD(cur_bi->bi_parent, cur_bi->bi_position);
set_dc_child_size(dc,
get_dc_child_size(dc) - del_num * (KEY_SIZE +
DC_SIZE));
mark_buffer_dirty(cur_bi->bi_parent);
}
}
/* delete n node pointers and items starting from given position */
static void internal_delete_childs(reiserfs_filsys_t *fs,
struct buffer_info *cur_bi, int from, int n)
{
int i_from;
i_from = (from == 0) ? from : from - 1;
/* delete n pointers starting from `from' position in CUR;
delete n keys starting from 'i_from' position in CUR;
*/
internal_delete_pointers_items(fs, cur_bi, from, i_from, n);
}
/* copy cpy_num node pointers and cpy_num - 1 items from buffer src to buffer dest
* last_first == FIRST_TO_LAST means, that we copy first items from src to tail of dest
* last_first == LAST_TO_FIRST means, that we copy last items from src to head of dest
*/
static void internal_copy_pointers_items(reiserfs_filsys_t *fs,
struct buffer_info *dest_bi,
struct buffer_head *src,
int last_first, int cpy_num)
{
/* ATTENTION! Number of node pointers in DEST is equal to number of items in DEST *
* as delimiting key have already inserted to buffer dest.*/
struct buffer_head *dest = dest_bi->bi_bh;
int nr_dest, nr_src;
int dest_order, src_order;
struct block_head *blkh;
struct reiserfs_key *key;
struct disk_child *dc;
nr_src = B_NR_ITEMS(src);
if (cpy_num == 0)
return;
/* coping */
blkh = B_BLK_HEAD(dest);
nr_dest = get_blkh_nr_items(blkh);
/*dest_order = (last_first == LAST_TO_FIRST) ? 0 : nr_dest; */
/*src_order = (last_first == LAST_TO_FIRST) ? (nr_src - cpy_num + 1) : 0; */
(last_first == LAST_TO_FIRST) ? (dest_order = 0, src_order =
nr_src - cpy_num + 1) : (dest_order =
nr_dest,
src_order =
0);
/* prepare space for cpy_num pointers */
dc = B_N_CHILD(dest, dest_order);
memmove(dc + cpy_num, dc, (nr_dest - dest_order) * DC_SIZE);
/* insert pointers */
memcpy(dc, B_N_CHILD(src, src_order), DC_SIZE * cpy_num);
/* prepare space for cpy_num - 1 item headers */
key = B_N_PDELIM_KEY(dest, dest_order);
memmove(key + cpy_num - 1, key,
KEY_SIZE * (nr_dest - dest_order) + DC_SIZE * (nr_dest +
cpy_num));
/* insert headers */
memcpy(key, B_N_PDELIM_KEY(src, src_order), KEY_SIZE * (cpy_num - 1));
/* sizes, item number */
set_blkh_nr_items(blkh, get_blkh_nr_items(blkh) + cpy_num - 1);
set_blkh_free_space(blkh, get_blkh_free_space(blkh) -
(KEY_SIZE * (cpy_num - 1) + DC_SIZE * cpy_num));
mark_buffer_dirty(dest);
if (dest_bi->bi_parent) {
dc = B_N_CHILD(dest_bi->bi_parent, dest_bi->bi_position);
set_dc_child_size(dc,
get_dc_child_size(dc) + KEY_SIZE * (cpy_num -
1) +
DC_SIZE * cpy_num);
mark_buffer_dirty(dest_bi->bi_parent);
}
}
/* Copy cpy_num node pointers and cpy_num - 1 items from buffer src to buffer dest.
* Delete cpy_num - del_par items and node pointers from buffer src.
* last_first == FIRST_TO_LAST means, that we copy/delete first items from src.
* last_first == LAST_TO_FIRST means, that we copy/delete last items from src.
*/
static void internal_move_pointers_items(reiserfs_filsys_t *fs,
struct buffer_info *dest_bi,
struct buffer_info *src_bi,
int last_first, int cpy_num,
int del_par)
{
int first_pointer;
int first_item;
internal_copy_pointers_items(fs, dest_bi, src_bi->bi_bh, last_first,
cpy_num);
if (last_first == FIRST_TO_LAST) { /* shift_left occurs */
first_pointer = 0;
first_item = 0;
/* delete cpy_num - del_par pointers and keys starting for pointers with first_pointer,
for key - with first_item */
internal_delete_pointers_items(fs, src_bi, first_pointer,
first_item, cpy_num - del_par);
} else { /* shift_right occurs */
int i, j;
i = (cpy_num - del_par ==
(j =
B_NR_ITEMS(src_bi->bi_bh)) + 1) ? 0 : j - cpy_num +
del_par;
internal_delete_pointers_items(fs, src_bi,
j + 1 - cpy_num + del_par, i,
cpy_num - del_par);
}
}
/* Insert n_src'th key of buffer src before n_dest'th key of buffer dest. */
static void internal_insert_key(reiserfs_filsys_t *fs, struct buffer_info *dest_bi, int dest_position_before, /* insert key before key with n_dest number */
struct buffer_head *src, int src_position)
{
struct buffer_head *dest = dest_bi->bi_bh;
int nr;
struct block_head *blkh;
struct reiserfs_key *key;
blkh = B_BLK_HEAD(dest);
nr = get_blkh_nr_items(blkh);
/* prepare space for inserting key */
key = B_N_PDELIM_KEY(dest, dest_position_before);
memmove(key + 1, key,
(nr - dest_position_before) * KEY_SIZE + (nr + 1) * DC_SIZE);
/* insert key */
memcpy(key, B_N_PDELIM_KEY(src, src_position), KEY_SIZE);
/* Change dirt, free space, item number fields. */
set_blkh_nr_items(blkh, get_blkh_nr_items(blkh) + 1);
set_blkh_free_space(blkh, get_blkh_free_space(blkh) - KEY_SIZE);
mark_buffer_dirty(dest);
if (dest_bi->bi_parent) {
struct disk_child *dc;
dc = B_N_CHILD(dest_bi->bi_parent, dest_bi->bi_position);
set_dc_child_size(dc, get_dc_child_size(dc) + KEY_SIZE);
mark_buffer_dirty(dest_bi->bi_parent);
}
}
/* Insert d_key'th (delimiting) key from buffer cfl to tail of dest.
* Copy pointer_amount node pointers and pointer_amount - 1 items from buffer src to buffer dest.
* Replace d_key'th key in buffer cfl.
* Delete pointer_amount items and node pointers from buffer src.
*/
/* this can be invoked both to shift from S to L and from R to S */
static void internal_shift_left(int mode, /* INTERNAL_FROM_S_TO_L | INTERNAL_FROM_R_TO_S */
struct tree_balance *tb, int h,
int pointer_amount)
{
struct buffer_info dest_bi, src_bi;
struct buffer_head *cf;
int d_key_position;
internal_define_dest_src_infos(mode, tb, h, &dest_bi, &src_bi,
&d_key_position, &cf);
/*printk("pointer_amount = %d\n",pointer_amount); */
if (pointer_amount) {
/* insert delimiting key from common father of dest and src to node dest into position B_NR_ITEM(dest) */
internal_insert_key(tb->tb_fs, &dest_bi,
B_NR_ITEMS(dest_bi.bi_bh), cf,
d_key_position);
if (B_NR_ITEMS(src_bi.bi_bh) == pointer_amount - 1) {
if (src_bi.bi_position /*src->b_item_order */ == 0)
replace_key(tb->tb_fs, cf, d_key_position,
src_bi.
bi_parent /*src->b_parent */ , 0);
} else
replace_key(tb->tb_fs, cf, d_key_position, src_bi.bi_bh,
pointer_amount - 1);
}
/* last parameter is del_parameter */
internal_move_pointers_items(tb->tb_fs, &dest_bi, &src_bi,
FIRST_TO_LAST, pointer_amount, 0);
}
/* Insert delimiting key to L[h].
* Copy n node pointers and n - 1 items from buffer S[h] to L[h].
* Delete n - 1 items and node pointers from buffer S[h].
*/
/* it always shifts from S[h] to L[h] */
static void internal_shift1_left(struct tree_balance *tb,
int h, int pointer_amount)
{
struct buffer_info dest_bi, src_bi;
struct buffer_head *cf;
int d_key_position;
internal_define_dest_src_infos(INTERNAL_SHIFT_FROM_S_TO_L, tb, h,
&dest_bi, &src_bi, &d_key_position, &cf);
if (pointer_amount > 0) /* insert lkey[h]-th key from CFL[h] to left neighbor L[h] */
internal_insert_key(tb->tb_fs, &dest_bi,
B_NR_ITEMS(dest_bi.bi_bh), cf,
d_key_position);
/* last parameter is del_parameter */
internal_move_pointers_items(tb->tb_fs, &dest_bi, &src_bi,
FIRST_TO_LAST, pointer_amount, 1);
}
/* Insert d_key'th (delimiting) key from buffer cfr to head of dest.
* Copy n node pointers and n - 1 items from buffer src to buffer dest.
* Replace d_key'th key in buffer cfr.
* Delete n items and node pointers from buffer src.
*/
static void internal_shift_right(int mode, /* INTERNAL_FROM_S_TO_R | INTERNAL_FROM_L_TO_S */
struct tree_balance *tb, int h,
int pointer_amount)
{
struct buffer_info dest_bi, src_bi;
struct buffer_head *cf;
int d_key_position;
int nr;
internal_define_dest_src_infos(mode, tb, h, &dest_bi, &src_bi,
&d_key_position, &cf);
nr = B_NR_ITEMS(src_bi.bi_bh);
if (pointer_amount > 0) {
/* insert delimiting key from common father of dest and src to dest node into position 0 */
internal_insert_key(tb->tb_fs, &dest_bi, 0, cf, d_key_position);
if (nr == pointer_amount - 1) {
/* when S[h] disappers replace left delemiting key as well */
if (tb->CFL[h])
replace_key(tb->tb_fs, cf, d_key_position,
tb->CFL[h], tb->lkey[h]);
} else
replace_key(tb->tb_fs, cf, d_key_position, src_bi.bi_bh,
nr - pointer_amount);
}
/* last parameter is del_parameter */
internal_move_pointers_items(tb->tb_fs, &dest_bi, &src_bi,
LAST_TO_FIRST, pointer_amount, 0);
}
/* Insert delimiting key to R[h].
* Copy n node pointers and n - 1 items from buffer S[h] to R[h].
* Delete n - 1 items and node pointers from buffer S[h].
*/
/* it always shift from S[h] to R[h] */
static void internal_shift1_right(struct tree_balance *tb,
int h, int pointer_amount)
{
struct buffer_info dest_bi, src_bi;
struct buffer_head *cf;
int d_key_position;
internal_define_dest_src_infos(INTERNAL_SHIFT_FROM_S_TO_R, tb, h,
&dest_bi, &src_bi, &d_key_position, &cf);
if (pointer_amount > 0) /* insert rkey from CFR[h] to right neighbor R[h] */
internal_insert_key(tb->tb_fs, &dest_bi, 0, cf, d_key_position);
/* last parameter is del_parameter */
internal_move_pointers_items(tb->tb_fs, &dest_bi, &src_bi,
LAST_TO_FIRST, pointer_amount, 1);
}
/* Delete insert_num node pointers together with their left items
* and balance current node.*/
static void balance_internal_when_delete(struct tree_balance *tb,
int h, int child_pos)
{
int insert_num;
int n;
struct buffer_head *tbSh = PATH_H_PBUFFER(tb->tb_path, h);
struct buffer_info bi;
insert_num = tb->insert_size[h] / ((int)(DC_SIZE + KEY_SIZE));
/* delete child-node-pointer(s) together with their left item(s) */
bi.bi_bh = tbSh;
bi.bi_parent = PATH_H_PPARENT(tb->tb_path, h);
bi.bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
internal_delete_childs(tb->tb_fs, &bi, child_pos, -insert_num);
n = B_NR_ITEMS(tbSh);
if (tb->lnum[h] == 0 && tb->rnum[h] == 0) {
if (tb->blknum[h] == 0) {
/* node S[h] (root of the tree) is empty now */
struct buffer_head *new_root;
struct reiserfs_super_block *sb;
/* choose a new root */
if (!tb->L[h - 1] || !B_NR_ITEMS(tb->L[h - 1]))
new_root = tb->R[h - 1];
else
new_root = tb->L[h - 1];
/* update super block's tree height and pointer to a root block */
sb = tb->tb_fs->fs_ondisk_sb;
set_sb_root_block(sb, new_root->b_blocknr);
set_sb_tree_height(sb, get_sb_tree_height(sb) - 1);
mark_buffer_dirty(tb->tb_fs->fs_super_bh);
tb->tb_fs->fs_dirt = 1;
/* mark buffer S[h] not uptodate and put it in free list */
reiserfs_invalidate_buffer(tb, tbSh, 1);
return;
}
return;
}
if (tb->L[h] && tb->lnum[h] == -B_NR_ITEMS(tb->L[h]) - 1) { /* join S[h] with L[h] */
internal_shift_left(INTERNAL_SHIFT_FROM_S_TO_L, tb, h, n + 1); /*tb->L[h], tb->CFL[h], tb->lkey[h], tb->S[h], n+1); */
reiserfs_invalidate_buffer(tb, tbSh, 1); /* preserve not needed, internal, 1 mean free block */
return;
}
if (tb->R[h] && tb->rnum[h] == -B_NR_ITEMS(tb->R[h]) - 1) { /* join S[h] with R[h] */
internal_shift_right(INTERNAL_SHIFT_FROM_S_TO_R, tb, h, n + 1);
reiserfs_invalidate_buffer(tb, tbSh, 1);
return;
}
if (tb->lnum[h] < 0) { /* borrow from left neighbor L[h] */
internal_shift_right(INTERNAL_SHIFT_FROM_L_TO_S, tb, h,
-tb->lnum[h]);
return;
}
if (tb->rnum[h] < 0) { /* borrow from right neighbor R[h] */
internal_shift_left(INTERNAL_SHIFT_FROM_R_TO_S, tb, h, -tb->rnum[h]); /*tb->S[h], tb->CFR[h], tb->rkey[h], tb->R[h], -tb->rnum[h]); */
return;
}
if (tb->lnum[h] > 0) { /* split S[h] into two parts and put them into neighbors */
internal_shift_left(INTERNAL_SHIFT_FROM_S_TO_L, tb, h, tb->lnum[h]); /*tb->L[h], tb->CFL[h], tb->lkey[h], tb->S[h], tb->lnum[h]); */
internal_shift_right(INTERNAL_SHIFT_FROM_S_TO_R, tb, h,
tb->rnum[h]);
reiserfs_invalidate_buffer(tb, tbSh, 1);
return;
}
reiserfs_panic("balance_internal_when_delete",
"unexpected tb->lnum[%d]==%d or tb->rnum[%d]==%d", h,
tb->lnum[h], h, tb->rnum[h]);
}
/* Replace delimiting key of buffers L[h] and S[h] by the given key.*/
void replace_lkey(struct tree_balance *tb, int h, struct item_head *key)
{
if (B_NR_ITEMS(PATH_H_PBUFFER(tb->tb_path, h)) == 0)
return;
memcpy(B_N_PDELIM_KEY(tb->CFL[h], tb->lkey[h]), key, KEY_SIZE);
mark_buffer_dirty(tb->CFL[h]);
}
/* Replace delimiting key of buffers S[h] and R[h] by the given key.*/
void replace_rkey(struct tree_balance *tb, int h, struct item_head *key)
{
memcpy(B_N_PDELIM_KEY(tb->CFR[h], tb->rkey[h]), key, KEY_SIZE);
mark_buffer_dirty(tb->CFR[h]);
}
int balance_internal(struct tree_balance *tb, /* tree_balance structure */
int h, /* level of the tree */
int child_pos, struct item_head *insert_key, /* key for insertion on higher level */
struct buffer_head **insert_ptr)
{ /* node for insertion on higher level */
/* if inserting/pasting
{
child_pos is the position of the node-pointer in S[h] that *
pointed to S[h-1] before balancing of the h-1 level; *
this means that new pointers and items must be inserted AFTER *
child_pos
}
else
{
it is the position of the leftmost pointer that must be deleted (together with
its corresponding key to the left of the pointer)
as a result of the previous level's balancing.
}
*/
struct buffer_head *tbSh = PATH_H_PBUFFER(tb->tb_path, h);
struct buffer_info bi;
int order; /* we return this: it is 0 if there is no S[h], else it is tb->S[h]->b_item_order */
int insert_num, n, k;
struct buffer_head *S_new;
struct item_head new_insert_key;
struct buffer_head *new_insert_ptr = NULL;
struct item_head *new_insert_key_addr = insert_key;
order =
(tbSh) ? PATH_H_POSITION(tb->tb_path,
h + 1) /*tb->S[h]->b_item_order */ : 0;
/* Using insert_size[h] calculate the number insert_num of items
that must be inserted to or deleted from S[h]. */
insert_num = tb->insert_size[h] / ((int)(KEY_SIZE + DC_SIZE));
/* Check whether insert_num is proper * */
/* Make balance in case insert_num < 0 */
if (insert_num < 0) {
balance_internal_when_delete(tb, h, child_pos);
return order;
}
k = 0;
if (tb->lnum[h] > 0) {
/* shift lnum[h] items from S[h] to the left neighbor L[h].
check how many of new items fall into L[h] or CFL[h] after shifting */
n = get_blkh_nr_items(B_BLK_HEAD(tb->L[h])); /* number of items in L[h] */
if (tb->lnum[h] <= child_pos) {
/* new items don't fall into L[h] or CFL[h] */
internal_shift_left(INTERNAL_SHIFT_FROM_S_TO_L, tb, h,
tb->lnum[h]);
child_pos -= tb->lnum[h];
} else if (tb->lnum[h] > child_pos + insert_num) {
/* all new items fall into L[h] */
internal_shift_left(INTERNAL_SHIFT_FROM_S_TO_L, tb, h,
tb->lnum[h] - insert_num);
/* insert insert_num keys and node-pointers into L[h] */
bi.bi_bh = tb->L[h];
bi.bi_parent = tb->FL[h];
bi.bi_position = get_left_neighbor_position(tb, h);
internal_insert_childs(tb->tb_fs, &bi,
/*tb->L[h], tb->S[h-1]->b_next */
n + child_pos + 1,
insert_num, insert_key,
insert_ptr);
insert_num = 0;
} else {
struct disk_child *dc;
/* some items fall into L[h] or CFL[h], but some don't fall */
internal_shift1_left(tb, h, child_pos + 1);
/* calculate number of new items that fall into L[h] */
k = tb->lnum[h] - child_pos - 1;
bi.bi_bh = tb->L[h];
bi.bi_parent = tb->FL[h];
bi.bi_position = get_left_neighbor_position(tb, h);
internal_insert_childs(tb->tb_fs, &bi,
/*tb->L[h], tb->S[h-1]->b_next, */
n + child_pos + 1, k,
insert_key, insert_ptr);
replace_lkey(tb, h, insert_key + k);
/* replace the first node-ptr in S[h] by node-ptr to insert_ptr[k] */
dc = B_N_CHILD(tbSh, 0);
set_dc(dc, MAX_CHILD_SIZE(insert_ptr[k]->b_size) -
get_blkh_free_space(B_BLK_HEAD(insert_ptr[k])),
insert_ptr[k]->b_blocknr);
/*
set_dc_child_size (dc, MAX_CHILD_SIZE(insert_ptr[k]->b_size) -
get_blkh_free_space (B_BLK_HEAD(insert_ptr[k])));
set_dc_child_blocknr (dc, insert_ptr[k]->b_blocknr);
*/
mark_buffer_dirty(tbSh);
k++;
insert_key += k;
insert_ptr += k;
insert_num -= k;
child_pos = 0;
}
}
/* tb->lnum[h] > 0 */
if (tb->rnum[h] > 0) {
/*shift rnum[h] items from S[h] to the right neighbor R[h] */
/* check how many of new items fall into R or CFR after shifting */
n = get_blkh_nr_items(B_BLK_HEAD(tbSh)); /* number of items in S[h] */
if (n - tb->rnum[h] >= child_pos)
/* new items fall into S[h] */
/*internal_shift_right(tb,h,tbSh,tb->CFR[h],tb->rkey[h],tb->R[h],tb->rnum[h]); */
internal_shift_right(INTERNAL_SHIFT_FROM_S_TO_R, tb, h,
tb->rnum[h]);
else if (n + insert_num - tb->rnum[h] < child_pos) {
/* all new items fall into R[h] */
internal_shift_right(INTERNAL_SHIFT_FROM_S_TO_R, tb, h,
tb->rnum[h] - insert_num);
/* insert insert_num keys and node-pointers into R[h] */
bi.bi_bh = tb->R[h];
bi.bi_parent = tb->FR[h];
bi.bi_position = get_right_neighbor_position(tb, h);
internal_insert_childs(tb->tb_fs, &bi,
/*tb->R[h],tb->S[h-1]->b_next */
child_pos - n - insert_num +
tb->rnum[h] - 1,
insert_num, insert_key,
insert_ptr);
insert_num = 0;
} else {
struct disk_child *dc;
/* one of the items falls into CFR[h] */
internal_shift1_right(tb, h, n - child_pos + 1);
/* calculate number of new items that fall into R[h] */
k = tb->rnum[h] - n + child_pos - 1;
bi.bi_bh = tb->R[h];
bi.bi_parent = tb->FR[h];
bi.bi_position = get_right_neighbor_position(tb, h);
internal_insert_childs(tb->tb_fs, &bi,
/*tb->R[h], tb->R[h]->b_child, */
0, k, insert_key + 1,
insert_ptr + 1);
replace_rkey(tb, h, insert_key + insert_num - k - 1);
/* replace the first node-ptr in R[h] by node-ptr insert_ptr[insert_num-k-1] */
dc = B_N_CHILD(tb->R[h], 0);
set_dc(dc,
MAX_CHILD_SIZE(insert_ptr[insert_num - k - 1]->
b_size) -
get_blkh_free_space(B_BLK_HEAD
(insert_ptr
[insert_num - k - 1])),
insert_ptr[insert_num - k - 1]->b_blocknr);
/*
set_dc_child_size (dc, MAX_CHILD_SIZE(insert_ptr[insert_num-k-1]->b_size) -
get_blkh_free_space (B_BLK_HEAD(insert_ptr[insert_num-k-1])));
set_dc_child_blocknr (dc, insert_ptr[insert_num-k-1]->b_blocknr);
*/
mark_buffer_dirty(tb->R[h]);
insert_num -= (k + 1);
}
}
/** Fill new node that appears instead of S[h] **/
if (!tb->blknum[h]) { /* node S[h] is empty now */
/* Mark buffer as invalid and put it to head of free list. */
reiserfs_invalidate_buffer(tb, tbSh, 1); /* do not preserve, internal node */
return order;
}
if (!tbSh) {
/* create new root */
struct disk_child *dc;
struct buffer_head *tbSh_1 = PATH_H_PBUFFER(tb->tb_path, h - 1);
struct reiserfs_super_block *sb;
if (tb->blknum[h] != 1)
reiserfs_panic(0, "balance_internal",
"One new node required for creating the new root");
/* S[h] = empty buffer from the list FEB. */
tbSh = get_FEB(tb);
set_blkh_level(B_BLK_HEAD(tbSh), h + 1);
/* Put the unique node-pointer to S[h] that points to S[h-1]. */
dc = B_N_CHILD(tbSh, 0);
set_dc(dc, MAX_CHILD_SIZE(tbSh_1->b_size) -
get_blkh_free_space(B_BLK_HEAD(tbSh_1)),
tbSh_1->b_blocknr);
/*
set_dc_child_size (dc, MAX_CHILD_SIZE (tbSh_1->b_size) - get_blkh_free_space (B_BLK_HEAD(tbSh_1)));
set_dc_child_blocknr (dc, tbSh_1->b_blocknr);
*/
tb->insert_size[h] -= DC_SIZE;
set_blkh_free_space(B_BLK_HEAD(tbSh),
get_blkh_free_space(B_BLK_HEAD(tbSh)) -
DC_SIZE);
mark_buffer_dirty(tbSh);
/* put new root into path structure */
PATH_OFFSET_PBUFFER(tb->tb_path, ILLEGAL_PATH_ELEMENT_OFFSET) =
tbSh;
/* Change root in structure super block. */
sb = tb->tb_fs->fs_ondisk_sb;
set_sb_root_block(sb, tbSh->b_blocknr);
set_sb_tree_height(sb, get_sb_tree_height(sb) + 1);
mark_buffer_dirty(tb->tb_fs->fs_super_bh);
tb->tb_fs->fs_dirt = 1;
}
if (tb->blknum[h] == 2) {
int snum;
struct buffer_info dest_bi, src_bi;
/* S_new = free buffer from list FEB */
S_new = get_FEB(tb);
set_blkh_level(B_BLK_HEAD(S_new), h + 1);
dest_bi.bi_bh = S_new;
dest_bi.bi_parent = 0;
dest_bi.bi_position = 0;
src_bi.bi_bh = tbSh;
src_bi.bi_parent = PATH_H_PPARENT(tb->tb_path, h);
src_bi.bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
n = get_blkh_nr_items(B_BLK_HEAD(tbSh)); /* number of items in S[h] */
snum = (insert_num + n + 1) / 2;
if (n - snum >= child_pos) {
/* new items don't fall into S_new */
/* store the delimiting key for the next level */
/* new_insert_key = (n - snum)'th key in S[h] */
memcpy(&new_insert_key, B_N_PDELIM_KEY(tbSh, n - snum),
KEY_SIZE);
/* last parameter is del_par */
internal_move_pointers_items(tb->tb_fs, &dest_bi,
&src_bi, LAST_TO_FIRST,
snum, 0);
} else if (n + insert_num - snum < child_pos) {
/* all new items fall into S_new */
/* store the delimiting key for the next level */
/* new_insert_key = (n + insert_item - snum)'th key in S[h] */
memcpy(&new_insert_key,
B_N_PDELIM_KEY(tbSh, n + insert_num - snum),
KEY_SIZE);
/* last parameter is del_par */
internal_move_pointers_items(tb->tb_fs, &dest_bi,
&src_bi, LAST_TO_FIRST,
snum - insert_num, 0);
/* internal_move_pointers_items(S_new,tbSh,1,snum - insert_num,0); */
/* insert insert_num keys and node-pointers into S_new */
internal_insert_childs(tb->tb_fs, &dest_bi,
/*S_new,tb->S[h-1]->b_next, */
child_pos - n - insert_num +
snum - 1,
insert_num, insert_key,
insert_ptr);
insert_num = 0;
} else {
struct disk_child *dc;
/* some items fall into S_new, but some don't fall */
/* last parameter is del_par */
internal_move_pointers_items(tb->tb_fs, &dest_bi,
&src_bi, LAST_TO_FIRST,
n - child_pos + 1, 1);
/* internal_move_pointers_items(S_new,tbSh,1,n - child_pos + 1,1); */
/* calculate number of new items that fall into S_new */
k = snum - n + child_pos - 1;
internal_insert_childs(tb->tb_fs, &dest_bi, /*S_new, */
0, k, insert_key + 1,
insert_ptr + 1);
/* new_insert_key = insert_key[insert_num - k - 1] */
memcpy(&new_insert_key, insert_key + insert_num - k - 1,
KEY_SIZE);
/* replace first node-ptr in S_new by node-ptr to insert_ptr[insert_num-k-1] */
dc = B_N_CHILD(S_new, 0);
set_dc(dc,
MAX_CHILD_SIZE(insert_ptr[insert_num - k - 1]->
b_size) -
get_blkh_free_space(B_BLK_HEAD
(insert_ptr
[insert_num - k - 1])),
insert_ptr[insert_num - k - 1]->b_blocknr);
/*
set_dc_child_size (dc, MAX_CHILD_SIZE(insert_ptr[insert_num-k-1]->b_size) -
get_blkh_free_space (B_BLK_HEAD(insert_ptr[insert_num-k-1])));
set_dc_child_blocknr (dc, insert_ptr[insert_num-k-1]->b_blocknr);
*/
mark_buffer_dirty(S_new);
insert_num -= (k + 1);
}
/* new_insert_ptr = node_pointer to S_new */
new_insert_ptr = S_new;
/*
S_new->b_count --;
*/
/*brelse(S_new); */
}
n = get_blkh_nr_items(B_BLK_HEAD(tbSh)); /*number of items in S[h] */
if (-1 <= child_pos && child_pos <= n && insert_num > 0) {
bi.bi_bh = tbSh;
bi.bi_parent = PATH_H_PPARENT(tb->tb_path, h);
bi.bi_position = PATH_H_POSITION(tb->tb_path, h + 1);
if (child_pos == -1) {
/* this is a little different from original do_balance:
here we insert the minimal keys in the tree, that has never happened when file system works */
if (tb->CFL[h - 1] || insert_num != 1 || h != 1)
die("balance_internal: invalid child_pos");
/* insert_child (tb->S[h], tb->S[h-1], child_pos, insert_num, B_N_ITEM_HEAD(tb->S[0],0), insert_ptr); */
internal_insert_childs(tb->tb_fs, &bi, child_pos,
insert_num,
B_N_PITEM_HEAD(PATH_PLAST_BUFFER
(tb->tb_path), 0),
insert_ptr);
} else
internal_insert_childs(tb->tb_fs, &bi, child_pos,
insert_num, insert_key,
insert_ptr);
}
memcpy(new_insert_key_addr, &new_insert_key, KEY_SIZE);
insert_ptr[0] = new_insert_ptr;
return order;
}
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