reiserfs: balance_leaf refactor, pull out balance_leaf_insert_right

This patch factors out a new balance_leaf_insert_right from the code in
balance_leaf responsible for inserting new items into the node to
the right of S[0] in the tree.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Jeff Mahoney 2014-04-23 10:00:49 -04:00 committed by Jan Kara
parent cf22df182b
commit e80ef3d148

View File

@ -508,6 +508,80 @@ static void balance_leaf_paste_left(struct tree_balance *tb,
}
static void balance_leaf_insert_right(struct tree_balance *tb,
struct item_head *ih, const char *body)
{
struct buffer_head *tbS0 = PATH_PLAST_BUFFER(tb->tb_path);
int n = B_NR_ITEMS(tbS0);
struct buffer_info bi;
int ret_val;
if (n - tb->rnum[0] < tb->item_pos) { /* new item or its part falls to R[0] */
if (tb->item_pos == n - tb->rnum[0] + 1 && tb->rbytes != -1) { /* part of new item falls into R[0] */
loff_t old_key_comp, old_len, r_zeroes_number;
const char *r_body;
int version;
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] */
offset = le_ih_k_offset(ih) + ((old_len - tb->rbytes) << (is_indirect_le_ih(ih) ? tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT : 0));
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_val = 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;
}
} else { /* new item or part of it doesn't fall into R[0] */
leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
}
}
/**
* balance_leaf - reiserfs tree balancing algorithm
* @tb: tree balance state
@ -588,69 +662,7 @@ static int balance_leaf(struct tree_balance *tb, struct item_head *ih,
switch (flag) {
case M_INSERT: /* insert item */
if (n - tb->rnum[0] < tb->item_pos) { /* new item or its part falls to R[0] */
if (tb->item_pos == n - tb->rnum[0] + 1 && tb->rbytes != -1) { /* part of new item falls into R[0] */
loff_t old_key_comp, old_len, r_zeroes_number;
const char *r_body;
int version;
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] */
offset = le_ih_k_offset(ih) + ((old_len - tb->rbytes) << (is_indirect_le_ih(ih) ? tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT : 0));
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_val = 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;
}
} else { /* new item or part of it doesn't fall into R[0] */
leaf_shift_right(tb, tb->rnum[0], tb->rbytes);
}
balance_leaf_insert_right(tb, ih, body);
break;
case M_PASTE: /* append item */