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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 00:20:36 +0200 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-17 00:20:36 +0200 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/reiserfs/do_balan.c | |
download | linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz linux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/reiserfs/do_balan.c')
-rw-r--r-- | fs/reiserfs/do_balan.c | 1597 |
1 files changed, 1597 insertions, 0 deletions
diff --git a/fs/reiserfs/do_balan.c b/fs/reiserfs/do_balan.c new file mode 100644 index 000000000000..2118db2896c7 --- /dev/null +++ b/fs/reiserfs/do_balan.c @@ -0,0 +1,1597 @@ +/* + * 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. */ + + +/** + ** balance_leaf_when_delete + ** balance_leaf + ** do_balance + ** + **/ + +#include <linux/config.h> +#include <asm/uaccess.h> +#include <linux/time.h> +#include <linux/reiserfs_fs.h> +#include <linux/buffer_head.h> + +#ifdef CONFIG_REISERFS_CHECK + +struct tree_balance * cur_tb = NULL; /* detects whether more than one + copy of tb exists as a means + of checking whether schedule + is interrupting do_balance */ +#endif + +inline void do_balance_mark_leaf_dirty (struct tree_balance * tb, + struct buffer_head * bh, int flag) +{ + journal_mark_dirty(tb->transaction_handle, + tb->transaction_handle->t_super, 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. + +It would be easier to read balance_leaf() if each of these summary +lines was a separate procedure rather than being inlined. I think +that there are many passages here and in balance_leaf_when_delete() in +which two calls to one procedure can replace two passages, and it +might save cache space and improve software maintenance costs to do so. + +Vladimir made the perceptive comment that we should offload most of +the decision making in this function into fix_nodes/check_balance, and +then create some sort of structure in tb that says what actions should +be performed by do_balance. + +-Hans */ + + + +/* 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); + int pos_in_item = tb->tb_path->pos_in_item; + 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 = B_N_PITEM_HEAD (tbS0, item_pos); + + /* Delete or truncate the item */ + + switch (flag) { + case M_DELETE: /* delete item in S[0] */ + + 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); + + bi.tb = tb; + bi.bi_bh = tbS0; + bi.bi_parent = PATH_H_PPARENT (tb->tb_path, 0); + bi.bi_position = PATH_H_POSITION (tb->tb_path, 1); + 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]); + + break; + + case M_CUT: { /* cut item in S[0] */ + bi.tb = tb; + bi.bi_bh = tbS0; + bi.bi_parent = PATH_H_PPARENT (tb->tb_path, 0); + bi.bi_position = PATH_H_POSITION (tb->tb_path, 1); + 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"); + } + break; + } + + default: + print_cur_tb ("12040"); + reiserfs_panic (tb->tb_sb, "PAP-12040: balance_leaf_when_delete: unexpectable mode: %s(%d)", + (flag == M_PASTE) ? "PASTE" : ((flag == M_INSERT) ? "INSERT" : "UNKNOWN"), flag); + } + + /* the rule is that no shifting occurs unless by shifting a node can be freed */ + n = B_NR_ITEMS(tbS0); + if ( tb->lnum[0] ) /* L[0] takes part in balancing */ + { + if ( tb->lnum[0] == -1 ) /* L[0] must be joined with S[0] */ + { + if ( tb->rnum[0] == -1 ) /* R[0] must be also joined with S[0] */ + { + 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; + } + + 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 int balance_leaf (struct tree_balance * tb, + struct item_head * ih, /* item header of inserted item (this is on little endian) */ + const char * body, /* body of inserted item or bytes to paste */ + int flag, /* i - insert, d - delete, c - cut, p - paste + (see comment to do_balance) */ + struct item_head * insert_key, /* 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 buffer_head ** insert_ptr /* inserted node-ptrs for the next level */ + ) +{ + struct buffer_head * tbS0 = PATH_PLAST_BUFFER (tb->tb_path); + int item_pos = PATH_LAST_POSITION (tb->tb_path); /* index into the array of item headers in S[0] + of the affected item */ + struct buffer_info bi; + struct buffer_head *S_new[2]; /* new nodes allocated to hold what could not fit into S */ + int snum[2]; /* number of items that will be placed + into S_new (includes partially shifted + items) */ + int sbytes[2]; /* if an item is partially shifted into S_new then + if it is a directory item + it is the number of entries from the item that are shifted into S_new + else + it is the number of bytes from the item that are shifted into S_new + */ + int n, i; + int ret_val; + int pos_in_item; + int zeros_num; + + 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); + + zeros_num = 0; + if (flag == M_INSERT && body == 0) + zeros_num = ih_item_len( ih ); + + pos_in_item = tb->tb_path->pos_in_item; + /* for indirect item pos_in_item is measured in unformatted node + pointers. Recalculate to bytes */ + if (flag != M_INSERT && is_indirect_le_ih (B_N_PITEM_HEAD (tbS0, item_pos))) + pos_in_item *= UNFM_P_SIZE; + + if ( tb->lnum[0] > 0 ) { + /* Shift lnum[0] items from S[0] to the left neighbor L[0] */ + if ( item_pos < tb->lnum[0] ) { + /* new item or it part falls to L[0], shift it too */ + n = B_NR_ITEMS(tb->L[0]); + + switch (flag) { + case M_INSERT: /* insert item into L[0] */ + + if ( item_pos == tb->lnum[0] - 1 && tb->lbytes != -1 ) { + /* part of new item falls into L[0] */ + int new_item_len; + int version; + + ret_val = 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] */ + bi.tb = tb; + bi.bi_bh = tb->L[0]; + bi.bi_parent = tb->FL[0]; + bi.bi_position = get_left_neighbor_position (tb, 0); + leaf_insert_into_buf (&bi, n + item_pos - ret_val, ih, body, + zeros_num > ih_item_len(ih) ? ih_item_len(ih) : zeros_num); + + version = ih_version (ih); + + /* Calculate key component, item length and body to insert into S[0] */ + set_le_ih_k_offset( ih, le_ih_k_offset( ih ) + (tb->lbytes << (is_indirect_le_ih(ih)?tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT:0)) ); + + put_ih_item_len( ih, new_item_len ); + if ( tb->lbytes > zeros_num ) { + body += (tb->lbytes - zeros_num); + zeros_num = 0; + } + else + zeros_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_val = leaf_shift_left(tb, tb->lnum[0]-1, tb->lbytes); + /* Insert new item into L[0] */ + bi.tb = tb; + bi.bi_bh = tb->L[0]; + bi.bi_parent = tb->FL[0]; + bi.bi_position = get_left_neighbor_position (tb, 0); + leaf_insert_into_buf (&bi, n + item_pos - ret_val, ih, body, zeros_num); + tb->insert_size[0] = 0; + zeros_num = 0; + } + break; + + case M_PASTE: /* append item in L[0] */ + + if ( item_pos == tb->lnum[0] - 1 && tb->lbytes != -1 ) { + /* we must shift the part of the appended item */ + if ( is_direntry_le_ih (B_N_PITEM_HEAD (tbS0, item_pos))) { + + RFALSE( zeros_num, + "PAP-12090: invalid parameter in case of a directory"); + /* directory item */ + if ( tb->lbytes > pos_in_item ) { + /* new directory entry falls into L[0] */ + struct item_head * pasted; + int l_pos_in_item = pos_in_item; + + /* Shift lnum[0] - 1 items in whole. Shift lbytes - 1 entries from given directory item */ + ret_val = leaf_shift_left(tb, tb->lnum[0], tb->lbytes - 1); + if ( ret_val && ! item_pos ) { + pasted = B_N_PITEM_HEAD(tb->L[0],B_NR_ITEMS(tb->L[0])-1); + l_pos_in_item += I_ENTRY_COUNT(pasted) - (tb->lbytes-1); + } + + /* Append given directory entry to directory item */ + bi.tb = tb; + bi.bi_bh = tb->L[0]; + bi.bi_parent = tb->FL[0]; + bi.bi_position = get_left_neighbor_position (tb, 0); + leaf_paste_in_buffer (&bi, n + item_pos - ret_val, l_pos_in_item, + tb->insert_size[0], body, zeros_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.bi_bh, n + item_pos - ret_val, 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 */ + pos_in_item -= tb->lbytes; + } + else { + /* regular object */ + RFALSE( tb->lbytes <= 0, + "PAP-12095: there is nothing to shift to L[0]. lbytes=%d", + tb->lbytes); + RFALSE( pos_in_item != ih_item_len(B_N_PITEM_HEAD(tbS0, item_pos)), + "PAP-12100: incorrect position to paste: item_len=%d, pos_in_item=%d", + ih_item_len(B_N_PITEM_HEAD(tbS0,item_pos)), pos_in_item); + + if ( tb->lbytes >= pos_in_item ) { + /* appended item will be in L[0] in whole */ + int l_n; + + /* this bytes number must be appended to the last item of L[h] */ + l_n = tb->lbytes - 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_val = leaf_shift_left(tb,tb->lnum[0], + ih_item_len(B_N_PITEM_HEAD(tbS0,item_pos))); + /* Append to body of item in L[0] */ + bi.tb = tb; + bi.bi_bh = tb->L[0]; + bi.bi_parent = tb->FL[0]; + bi.bi_position = get_left_neighbor_position (tb, 0); + leaf_paste_in_buffer( + &bi,n + item_pos - ret_val, + ih_item_len( B_N_PITEM_HEAD(tb->L[0],n+item_pos-ret_val)), + l_n,body, zeros_num > l_n ? l_n : zeros_num + ); + /* 0-th item in S0 can be only of DIRECT type when l_n != 0*/ + { + int version; + int temp_l = l_n; + + RFALSE (ih_item_len (B_N_PITEM_HEAD (tbS0, 0)), + "PAP-12106: item length must be 0"); + RFALSE (comp_short_le_keys (B_N_PKEY (tbS0, 0), + B_N_PKEY (tb->L[0], + n + item_pos - ret_val)), + "PAP-12107: items must be of the same file"); + if (is_indirect_le_ih(B_N_PITEM_HEAD (tb->L[0], + n + item_pos - ret_val))) { + temp_l = l_n << (tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT); + } + /* update key of first item in S0 */ + version = ih_version (B_N_PITEM_HEAD (tbS0, 0)); + set_le_key_k_offset (version, B_N_PKEY (tbS0, 0), + le_key_k_offset (version, B_N_PKEY (tbS0, 0)) + temp_l); + /* update left delimiting key */ + set_le_key_k_offset (version, B_N_PDELIM_KEY(tb->CFL[0],tb->lkey[0]), + le_key_k_offset (version, B_N_PDELIM_KEY(tb->CFL[0],tb->lkey[0])) + temp_l); + } + + /* Calculate new body, position in item and insert_size[0] */ + if ( l_n > zeros_num ) { + body += (l_n - zeros_num); + zeros_num = 0; + } + else + zeros_num -= l_n; + pos_in_item = 0; + + RFALSE( comp_short_le_keys + (B_N_PKEY(tbS0,0), + B_N_PKEY(tb->L[0],B_NR_ITEMS(tb->L[0])-1)) || + + !op_is_left_mergeable + (B_N_PKEY (tbS0, 0), tbS0->b_size) || + !op_is_left_mergeable + (B_N_PDELIM_KEY(tb->CFL[0],tb->lkey[0]), + 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] */ + pos_in_item -= tb->lbytes; + + RFALSE( pos_in_item <= 0, + "PAP-12125: no place for paste. pos_in_item=%d", 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); + } + } + } + else /* appended item will be in L[0] in whole */ + { + struct item_head * pasted; + + if ( ! item_pos && op_is_left_mergeable (B_N_PKEY (tbS0, 0), tbS0->b_size) ) + { /* if we paste into first item of S[0] and it is left mergable */ + /* then increment pos_in_item by the size of the last item in L[0] */ + pasted = B_N_PITEM_HEAD(tb->L[0],n-1); + if ( is_direntry_le_ih (pasted) ) + pos_in_item += ih_entry_count(pasted); + else + pos_in_item += ih_item_len(pasted); + } + + /* Shift lnum[0] - 1 items in whole. Shift lbytes - 1 byte from item number lnum[0] */ + ret_val = leaf_shift_left(tb,tb->lnum[0],tb->lbytes); + /* Append to body of item in L[0] */ + bi.tb = tb; + bi.bi_bh = tb->L[0]; + bi.bi_parent = tb->FL[0]; + bi.bi_position = get_left_neighbor_position (tb, 0); + leaf_paste_in_buffer (&bi, n + item_pos - ret_val, pos_in_item, tb->insert_size[0], + body, zeros_num); + + /* if appended item is directory, paste entry */ + pasted = B_N_PITEM_HEAD (tb->L[0], n + item_pos - ret_val); + if (is_direntry_le_ih (pasted)) + leaf_paste_entries ( + bi.bi_bh, n + item_pos - ret_val, 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; + zeros_num = 0; + } + break; + default: /* cases d and t */ + reiserfs_panic (tb->tb_sb, "PAP-12130: balance_leaf: lnum > 0: unexpectable mode: %s(%d)", + (flag == M_DELETE) ? "DELETE" : ((flag == M_CUT) ? "CUT" : "UNKNOWN"), flag); + } + } else { + /* new item doesn't fall into L[0] */ + leaf_shift_left(tb,tb->lnum[0],tb->lbytes); + } + } /* tb->lnum[0] > 0 */ + + /* Calculate new item position */ + item_pos -= ( tb->lnum[0] - (( tb->lbytes != -1 ) ? 1 : 0)); + + if ( tb->rnum[0] > 0 ) { + /* shift rnum[0] items from S[0] to the right neighbor R[0] */ + n = B_NR_ITEMS(tbS0); + switch ( flag ) { + + case M_INSERT: /* insert item */ + if ( n - tb->rnum[0] < item_pos ) + { /* new item or its part falls to R[0] */ + if ( 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_zeros_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] */ + bi.tb = tb; + bi.bi_bh = tb->R[0]; + bi.bi_parent = tb->FR[0]; + bi.bi_position = get_right_neighbor_position (tb, 0); + if ( (old_len - tb->rbytes) > zeros_num ) { + r_zeros_number = 0; + r_body = body + (old_len - tb->rbytes) - zeros_num; + } + else { + r_body = body; + r_zeros_number = zeros_num - (old_len - tb->rbytes); + zeros_num -= r_zeros_number; + } + + leaf_insert_into_buf (&bi, 0, ih, r_body, r_zeros_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] */ + bi.tb = tb; + bi.bi_bh = tb->R[0]; + bi.bi_parent = tb->FR[0]; + bi.bi_position = get_right_neighbor_position (tb, 0); + leaf_insert_into_buf (&bi, item_pos - n + tb->rnum[0] - 1, ih, body, zeros_num); + + if ( item_pos - n + tb->rnum[0] - 1 == 0 ) { + replace_key(tb, tb->CFR[0],tb->rkey[0],tb->R[0],0); + + } + zeros_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); + } + break; + + case M_PASTE: /* append item */ + + if ( n - tb->rnum[0] <= item_pos ) /* pasted item or part of it falls to R[0] */ + { + if ( item_pos == n - tb->rnum[0] && tb->rbytes != -1 ) + { /* we must shift the part of the appended item */ + if ( is_direntry_le_ih (B_N_PITEM_HEAD(tbS0, item_pos))) + { /* we append to directory item */ + int entry_count; + + RFALSE( zeros_num, + "PAP-12145: invalid parameter in case of a directory"); + entry_count = I_ENTRY_COUNT(B_N_PITEM_HEAD(tbS0, item_pos)); + if ( entry_count - tb->rbytes < pos_in_item ) + /* new directory entry falls into R[0] */ + { + 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 = pos_in_item - entry_count + tb->rbytes - 1; + bi.tb = tb; + bi.bi_bh = tb->R[0]; + bi.bi_parent = tb->FR[0]; + bi.bi_position = get_right_neighbor_position (tb, 0); + leaf_paste_in_buffer (&bi, 0, paste_entry_position, + tb->insert_size[0],body,zeros_num); + /* paste entry */ + leaf_paste_entries ( + bi.bi_bh, 0, paste_entry_position, 1, (struct reiserfs_de_head *)body, + body + DEH_SIZE, tb->insert_size[0] + ); + + if ( paste_entry_position == 0 ) { + /* change delimiting keys */ + replace_key(tb, tb->CFR[0],tb->rkey[0],tb->R[0],0); + } + + tb->insert_size[0] = 0; + pos_in_item++; + } + else /* new directory entry doesn't fall into R[0] */ + { + leaf_shift_right(tb,tb->rnum[0],tb->rbytes); + } + } + else /* regular object */ + { + int n_shift, n_rem, r_zeros_number; + const char * r_body; + + /* Calculate number of bytes which must be shifted from appended item */ + if ( (n_shift = tb->rbytes - tb->insert_size[0]) < 0 ) + n_shift = 0; + + RFALSE(pos_in_item != ih_item_len(B_N_PITEM_HEAD (tbS0, item_pos)), + "PAP-12155: invalid position to paste. ih_item_len=%d, pos_in_item=%d", + pos_in_item, ih_item_len( B_N_PITEM_HEAD(tbS0,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] */ + if ( (n_rem = tb->insert_size[0] - tb->rbytes) < 0 ) + n_rem = 0; + + { + int version; + unsigned long temp_rem = n_rem; + + version = ih_version (B_N_PITEM_HEAD (tb->R[0],0)); + if (is_indirect_le_key(version,B_N_PKEY(tb->R[0],0))){ + temp_rem = n_rem << (tb->tb_sb->s_blocksize_bits - + UNFM_P_SHIFT); + } + set_le_key_k_offset (version, B_N_PKEY(tb->R[0],0), + le_key_k_offset (version, B_N_PKEY(tb->R[0],0)) + temp_rem); + set_le_key_k_offset (version, B_N_PDELIM_KEY(tb->CFR[0],tb->rkey[0]), + le_key_k_offset (version, B_N_PDELIM_KEY(tb->CFR[0],tb->rkey[0])) + temp_rem); + } +/* k_offset (B_N_PKEY(tb->R[0],0)) += n_rem; + k_offset (B_N_PDELIM_KEY(tb->CFR[0],tb->rkey[0])) += n_rem;*/ + do_balance_mark_internal_dirty (tb, tb->CFR[0], 0); + + /* Append part of body into R[0] */ + bi.tb = tb; + bi.bi_bh = tb->R[0]; + bi.bi_parent = tb->FR[0]; + bi.bi_position = get_right_neighbor_position (tb, 0); + if ( n_rem > zeros_num ) { + r_zeros_number = 0; + r_body = body + n_rem - zeros_num; + } + else { + r_body = body; + r_zeros_number = zeros_num - n_rem; + zeros_num -= r_zeros_number; + } + + leaf_paste_in_buffer(&bi, 0, n_shift, tb->insert_size[0] - n_rem, r_body, r_zeros_number); + + if (is_indirect_le_ih (B_N_PITEM_HEAD(tb->R[0],0))) { +#if 0 + RFALSE( n_rem, + "PAP-12160: paste more than one unformatted node pointer"); +#endif + set_ih_free_space (B_N_PITEM_HEAD(tb->R[0],0), 0); + } + tb->insert_size[0] = n_rem; + if ( ! n_rem ) + pos_in_item ++; + } + } + else /* pasted item in whole falls into R[0] */ + { + struct item_head * pasted; + + ret_val = leaf_shift_right(tb,tb->rnum[0],tb->rbytes); + /* append item in R[0] */ + if ( pos_in_item >= 0 ) { + bi.tb = tb; + bi.bi_bh = tb->R[0]; + bi.bi_parent = tb->FR[0]; + bi.bi_position = get_right_neighbor_position (tb, 0); + leaf_paste_in_buffer(&bi,item_pos - n + tb->rnum[0], pos_in_item, + tb->insert_size[0],body, zeros_num); + } + + /* paste new entry, if item is directory item */ + pasted = B_N_PITEM_HEAD(tb->R[0], item_pos - n + tb->rnum[0]); + if (is_direntry_le_ih (pasted) && pos_in_item >= 0 ) { + leaf_paste_entries ( + bi.bi_bh, item_pos - n + tb->rnum[0], pos_in_item, 1, + (struct reiserfs_de_head *)body, body + DEH_SIZE, tb->insert_size[0] + ); + if ( ! pos_in_item ) { + + RFALSE( 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); + zeros_num = tb->insert_size[0] = 0; + } + } + else /* new item doesn't fall into R[0] */ + { + leaf_shift_right(tb,tb->rnum[0],tb->rbytes); + } + break; + default: /* cases d and t */ + reiserfs_panic (tb->tb_sb, "PAP-12175: balance_leaf: rnum > 0: unexpectable mode: %s(%d)", + (flag == M_DELETE) ? "DELETE" : ((flag == M_CUT) ? "CUT" : "UNKNOWN"), 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: balance_leaf: CFR not initialized"); + copy_key (B_N_PDELIM_KEY (tb->CFL[0], tb->lkey[0]), B_N_PDELIM_KEY (tb->CFR[0], tb->rkey[0])); + do_balance_mark_internal_dirty (tb, tb->CFL[0], 0); + } + + reiserfs_invalidate_buffer(tb,tbS0); + return 0; + } + + + /* Fill new nodes that appear in place of S[0] */ + + /* I am told that this copying is because we need an array to enable + the looping code. -Hans */ + snum[0] = tb->s1num, + snum[1] = tb->s2num; + sbytes[0] = tb->s1bytes; + sbytes[1] = tb->s2bytes; + for( i = tb->blknum[0] - 2; i >= 0; i-- ) { + + RFALSE( !snum[i], "PAP-12200: snum[%d] == %d. Must be > 0", i, snum[i]); + + /* here we shift from S to S_new nodes */ + + S_new[i] = get_FEB(tb); + + /* initialized block type and tree level */ + set_blkh_level( B_BLK_HEAD(S_new[i]), DISK_LEAF_NODE_LEVEL ); + + + n = B_NR_ITEMS(tbS0); + + switch (flag) { + case M_INSERT: /* insert item */ + + if ( n - snum[i] < item_pos ) + { /* new item or it's part falls to first new node S_new[i]*/ + if ( item_pos == n - snum[i] + 1 && sbytes[i] != -1 ) + { /* part of new item falls into S_new[i] */ + int old_key_comp, old_len, r_zeros_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, snum[i] - 1, -1, 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] */ + set_le_ih_k_offset( ih, + le_ih_k_offset(ih) + ((old_len - sbytes[i] )<<(is_indirect_le_ih(ih)?tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT:0)) ); + + put_ih_item_len( ih, sbytes[i] ); + + /* Insert part of the item into S_new[i] before 0-th item */ + bi.tb = tb; + bi.bi_bh = S_new[i]; + bi.bi_parent = NULL; + bi.bi_position = 0; + + if ( (old_len - sbytes[i]) > zeros_num ) { + r_zeros_number = 0; + r_body = body + (old_len - sbytes[i]) - zeros_num; + } + else { + r_body = body; + r_zeros_number = zeros_num - (old_len - sbytes[i]); + zeros_num -= r_zeros_number; + } + + leaf_insert_into_buf (&bi, 0, ih, r_body, r_zeros_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 - sbytes[i] ); + tb->insert_size[0] -= 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, snum[i] - 1, sbytes[i], S_new[i]); + + /* Insert new item into S_new[i] */ + bi.tb = tb; + bi.bi_bh = S_new[i]; + bi.bi_parent = NULL; + bi.bi_position = 0; + leaf_insert_into_buf (&bi, item_pos - n + snum[i] - 1, ih, body, zeros_num); + + zeros_num = tb->insert_size[0] = 0; + } + } + + else /* new item or it part don't falls into S_new[i] */ + { + leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i], sbytes[i], S_new[i]); + } + break; + + case M_PASTE: /* append item */ + + if ( n - snum[i] <= item_pos ) /* pasted item or part if it falls to S_new[i] */ + { + if ( item_pos == n - snum[i] && sbytes[i] != -1 ) + { /* we must shift part of the appended item */ + struct item_head * aux_ih; + + RFALSE( ih, "PAP-12210: ih must be 0"); + + if ( is_direntry_le_ih (aux_ih = B_N_PITEM_HEAD(tbS0,item_pos))) { + /* we append to directory item */ + + int entry_count; + + entry_count = ih_entry_count(aux_ih); + + if ( entry_count - sbytes[i] < pos_in_item && 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( sbytes[i] - 1 >= entry_count, + "PAP-12220: there are no so much entries (%d), only %d", + 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, snum[i], sbytes[i]-1, S_new[i]); + /* Paste given directory entry to directory item */ + bi.tb = tb; + bi.bi_bh = S_new[i]; + bi.bi_parent = NULL; + bi.bi_position = 0; + leaf_paste_in_buffer (&bi, 0, pos_in_item - entry_count + sbytes[i] - 1, + tb->insert_size[0], body,zeros_num); + /* paste new directory entry */ + leaf_paste_entries ( + bi.bi_bh, 0, pos_in_item - entry_count + sbytes[i] - 1, + 1, (struct reiserfs_de_head *)body, body + DEH_SIZE, + tb->insert_size[0] + ); + tb->insert_size[0] = 0; + pos_in_item++; + } else { /* new directory entry doesn't fall into S_new[i] */ + leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i], sbytes[i], S_new[i]); + } + } + else /* regular object */ + { + int n_shift, n_rem, r_zeros_number; + const char * r_body; + + RFALSE( pos_in_item != ih_item_len(B_N_PITEM_HEAD(tbS0,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 = sbytes[i] - tb->insert_size[0]; + if ( n_shift < 0 ) + n_shift = 0; + leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i], n_shift, S_new[i]); + + /* Calculate number of bytes which must remain in body after append to S_new[i] */ + n_rem = tb->insert_size[0] - sbytes[i]; + if ( n_rem < 0 ) + n_rem = 0; + /* Append part of body into S_new[0] */ + bi.tb = tb; + bi.bi_bh = S_new[i]; + bi.bi_parent = NULL; + bi.bi_position = 0; + + if ( n_rem > zeros_num ) { + r_zeros_number = 0; + r_body = body + n_rem - zeros_num; + } + else { + r_body = body; + r_zeros_number = zeros_num - n_rem; + zeros_num -= r_zeros_number; + } + + leaf_paste_in_buffer(&bi, 0, n_shift, tb->insert_size[0]-n_rem, r_body,r_zeros_number); + { + struct item_head * tmp; + + tmp = B_N_PITEM_HEAD(S_new[i],0); + if (is_indirect_le_ih (tmp)) { + set_ih_free_space (tmp, 0); + set_le_ih_k_offset( tmp, le_ih_k_offset(tmp) + + (n_rem << (tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT))); + } else { + set_le_ih_k_offset( tmp, le_ih_k_offset(tmp) + + n_rem ); + } + } + + tb->insert_size[0] = n_rem; + if ( ! n_rem ) + pos_in_item++; + } + } + else + /* item falls wholly into S_new[i] */ + { + int ret_val; + struct item_head * pasted; + +#ifdef CONFIG_REISERFS_CHECK + struct item_head * ih = B_N_PITEM_HEAD(tbS0,item_pos); + + if ( ! is_direntry_le_ih(ih) && (pos_in_item != ih_item_len(ih) || + tb->insert_size[0] <= 0) ) + reiserfs_panic (tb->tb_sb, "PAP-12235: balance_leaf: pos_in_item must be equal to ih_item_len"); +#endif /* CONFIG_REISERFS_CHECK */ + + ret_val = leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i], sbytes[i], S_new[i]); + + RFALSE( ret_val, + "PAP-12240: unexpected value returned by leaf_move_items (%d)", + ret_val); + + /* paste into item */ + bi.tb = tb; + bi.bi_bh = S_new[i]; + bi.bi_parent = NULL; + bi.bi_position = 0; + leaf_paste_in_buffer(&bi, item_pos - n + snum[i], pos_in_item, tb->insert_size[0], body, zeros_num); + + pasted = B_N_PITEM_HEAD(S_new[i], item_pos - n + snum[i]); + if (is_direntry_le_ih (pasted)) + { + leaf_paste_entries ( + bi.bi_bh, item_pos - n + snum[i], 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); + zeros_num = tb->insert_size[0] = 0; + } + } + + else /* pasted item doesn't fall into S_new[i] */ + { + leaf_move_items (LEAF_FROM_S_TO_SNEW, tb, snum[i], sbytes[i], S_new[i]); + } + break; + default: /* cases d and t */ + reiserfs_panic (tb->tb_sb, "PAP-12245: balance_leaf: blknum > 2: unexpectable mode: %s(%d)", + (flag == M_DELETE) ? "DELETE" : ((flag == M_CUT) ? "CUT" : "UNKNOWN"), flag); + } + + memcpy (insert_key + i,B_N_PKEY(S_new[i],0),KEY_SIZE); + insert_ptr[i] = S_new[i]; + + RFALSE (!buffer_journaled (S_new [i]) || buffer_journal_dirty (S_new [i]) || + buffer_dirty (S_new [i]), + "PAP-12247: S_new[%d] : (%b)", i, S_new[i]); + } + + /* 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 */ + if ( 0 <= item_pos && item_pos < tb->s0num ) + { /* if we must insert or append into buffer S[0] */ + + switch (flag) + { + case M_INSERT: /* insert item into S[0] */ + bi.tb = tb; + bi.bi_bh = tbS0; + bi.bi_parent = PATH_H_PPARENT (tb->tb_path, 0); + bi.bi_position = PATH_H_POSITION (tb->tb_path, 1); + leaf_insert_into_buf (&bi, item_pos, ih, body, zeros_num); + + /* If we insert the first key change the delimiting key */ + if( item_pos == 0 ) { + if (tb->CFL[0]) /* can be 0 in reiserfsck */ + replace_key(tb, tb->CFL[0], tb->lkey[0],tbS0,0); + + } + break; + + case M_PASTE: { /* append item in S[0] */ + struct item_head * pasted; + + pasted = B_N_PITEM_HEAD (tbS0, item_pos); + /* when directory, may be new entry already pasted */ + if (is_direntry_le_ih (pasted)) { + if ( pos_in_item >= 0 && + pos_in_item <= ih_entry_count(pasted) ) { + + RFALSE( ! tb->insert_size[0], + "PAP-12260: insert_size is 0 already"); + + /* prepare space */ + bi.tb = tb; + bi.bi_bh = tbS0; + bi.bi_parent = PATH_H_PPARENT (tb->tb_path, 0); + bi.bi_position = PATH_H_POSITION (tb->tb_path, 1); + leaf_paste_in_buffer(&bi, item_pos, pos_in_item, tb->insert_size[0], body, zeros_num); + + /* paste entry */ + leaf_paste_entries ( + bi.bi_bh, item_pos, pos_in_item, 1, (struct reiserfs_de_head *)body, + body + DEH_SIZE, tb->insert_size[0] + ); + if ( ! item_pos && ! 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; + } + } else { /* regular object */ + if ( 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]); + bi.tb = tb; + bi.bi_bh = tbS0; + bi.bi_parent = PATH_H_PPARENT (tb->tb_path, 0); + bi.bi_position = PATH_H_POSITION (tb->tb_path, 1); + leaf_paste_in_buffer (&bi, item_pos, pos_in_item, tb->insert_size[0], body, zeros_num); + + if (is_indirect_le_ih (pasted)) { +#if 0 + RFALSE( tb->insert_size[0] != UNFM_P_SIZE, + "PAP-12280: insert_size for indirect item must be %d, not %d", + UNFM_P_SIZE, tb->insert_size[0]); +#endif + 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: balance_leaf: insert_size must be 0 (%d)", tb->insert_size[0]); + } + } +#endif /* CONFIG_REISERFS_CHECK */ + + } + } /* case M_PASTE: */ + } + } + +#ifdef CONFIG_REISERFS_CHECK + if ( flag == M_PASTE && tb->insert_size[0] ) { + print_cur_tb ("12290"); + reiserfs_panic (tb->tb_sb, "PAP-12290: balance_leaf: insert_size is still not 0 (%d)", tb->insert_size[0]); + } +#endif /* CONFIG_REISERFS_CHECK */ + + return 0; +} /* Leaf level of the tree is balanced (end of balance_leaf) */ + + + +/* 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_head * first_b; + struct buffer_info bi; + + for (i = 0; i < MAX_FEB_SIZE; i ++) + if (tb->FEB[i] != 0) + break; + + if (i == MAX_FEB_SIZE) + reiserfs_panic(tb->tb_sb, "vs-12300: get_FEB: FEB list is empty"); + + bi.tb = tb; + bi.bi_bh = first_b = tb->FEB[i]; + bi.bi_parent = NULL; + bi.bi_position = 0; + make_empty_node (&bi); + set_buffer_uptodate(first_b); + tb->FEB[i] = NULL; + tb->used[i] = first_b; + + return(first_b); +} + + +/* 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, "store_thrown deals with dirty buffer"); + for (i = 0; i < sizeof (tb->thrown)/sizeof (tb->thrown[0]); i ++) + if (!tb->thrown[i]) { + tb->thrown[i] = bh; + get_bh(bh) ; /* free_thrown puts this */ + return; + } + reiserfs_warning (tb->tb_sb, "store_thrown: too many thrown buffers"); +} + +static void free_thrown(struct tree_balance *tb) { + int i ; + b_blocknr_t blocknr ; + for (i = 0; i < sizeof (tb->thrown)/sizeof (tb->thrown[0]); i++) { + if (tb->thrown[i]) { + blocknr = tb->thrown[i]->b_blocknr ; + if (buffer_dirty (tb->thrown[i])) + reiserfs_warning (tb->tb_sb, + "free_thrown deals 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 (B_N_PDELIM_KEY(dest,n_dest), B_N_PITEM_HEAD(src,n_src), KEY_SIZE); + else + memcpy (B_N_PDELIM_KEY(dest,n_dest), B_N_PDELIM_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) == 0 || tb->FL[h] == 0, + "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) == 0 || tb->FR[h] == 0, + "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: check_internal_node: invalid child pointer %y in %b", dc, bh); + } + } +} + + +static int locked_or_not_in_tree (struct buffer_head * bh, char * which) +{ + if ( (!buffer_journal_prepared (bh) && buffer_locked (bh)) || + !B_IS_IN_TREE (bh) ) { + reiserfs_warning (NULL, "vs-12339: locked_or_not_in_tree: %s (%b)", + which, bh); + return 1; + } + return 0; +} + + +static int check_before_balancing (struct tree_balance * tb) +{ + int retval = 0; + + if ( cur_tb ) { + reiserfs_panic (tb->tb_sb, "vs-12335: check_before_balancing: " + "suspect that schedule occurred based on cur_tb not being null at this point in code. " + "do_balance cannot properly handle schedule occurring while it runs."); + } + + /* 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->L[0], "L[0]"); + retval |= locked_or_not_in_tree (tb->FL[0], "FL[0]"); + retval |= locked_or_not_in_tree (tb->CFL[0], "CFL[0]"); + check_leaf (tb->L[0]); + } + if ( tb->rnum[0] ) { + retval |= locked_or_not_in_tree (tb->R[0], "R[0]"); + retval |= locked_or_not_in_tree (tb->FR[0], "FR[0]"); + retval |= locked_or_not_in_tree (tb->CFR[0], "CFR[0]"); + check_leaf (tb->R[0]); + } + retval |= locked_or_not_in_tree (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: check_after_balance_leaf: 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: check_after_balance_leaf: 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, + "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: check_after_balance_leaf: 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 + 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); + 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) ; +} + + + + + +void do_balance (struct tree_balance * tb, /* tree_balance structure */ + struct item_head * ih, /* item header of inserted item */ + const char * body, /* body of inserted item or bytes to paste */ + int 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. */ +{ + int child_pos, /* position of a child node in its parent */ + h; /* level of the tree being processed */ + struct item_head insert_key[2]; /* 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 buffer_head *insert_ptr[2]; /* inserted node-ptrs for the next + level */ + + tb->tb_mode = flag; + tb->need_balance_dirty = 0; + + if (FILESYSTEM_CHANGED_TB(tb)) { + reiserfs_panic(tb->tb_sb, "clm-6000: do_balance, fs generation has changed\n") ; + } + /* if we have no real work to do */ + if ( ! tb->insert_size[0] ) { + reiserfs_warning (tb->tb_sb, + "PAP-12350: do_balance: 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); + +} |