* 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
- **
- **/
+/*
+ * 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 <asm/uaccess.h>
#include <linux/time.h>
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);
+ 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.
-
-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
+/*
+ * 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
+ * >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;
/* Delete or truncate the item */
- switch (flag) {
- case M_DELETE: /* delete item in S[0] */
+ 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);
- 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);
- leaf_delete_items(&bi, 0, item_pos, 1, -1);
+ /*
+ * the rule is that no shifting occurs unless by shifting
+ * a node can be freed
+ */
+ n = B_NR_ITEMS(tbS0);
- 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]);
+ /* L[0] takes part in balancing */
+ if (tb->lnum[0])
+ return balance_leaf_when_delete_left(tb);
- break;
+ 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;
+ }
- case M_CUT:{ /* cut item in S[0] */
- if (is_direntry_le_ih(ih)) {
+ RFALSE(tb->rnum[0],
+ "PAP-12065: bad rnum parameter must be 0 (%d)", tb->rnum[0]);
+ return 0;
+}
- /* 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]);
+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;
+}
- RFALSE(!item_pos && !pos_in_item && !tb->CFL[0],
- "PAP-12030: can not change delimiting key. CFL[0]=%p",
- tb->CFL[0]);
+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;
- 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(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);
+ }
- RFALSE(!ih_item_len(ih),
- "PAP-12035: cut must leave non-zero dynamic length of item");
- }
- break;
+ /* 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;
+}
+
- default:
- print_cur_tb("12040");
- reiserfs_panic(tb->tb_sb, "PAP-12040",
- "unexpected mode: %s(%d)",
- (flag ==
- M_PASTE) ? "PASTE" : ((flag ==
- M_INSERT) ? "INSERT" :
- "UNKNOWN"), flag);
+/* 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);
}
- /* 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);
+ /*
+ * 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);
- /* right_delimiting_key is correct in R[0] */
- replace_key(tb, tb->CFR[0], tb->rkey[0],
- tb->R[0], 0);
+ tb->insert_size[0] = 0;
+ tb->zeroes_num = 0;
+}
- reiserfs_invalidate_buffer(tb, tbS0);
- reiserfs_invalidate_buffer(tb, tb->L[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;
+}
- return -1;
- }
+/* 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;
- 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);
+ /* 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);
- reiserfs_invalidate_buffer(tb, tbS0);
+ 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;
- return 0;
+ /* 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;
}
- /* 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_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);
+ }
+}
- reiserfs_invalidate_buffer(tb, tbS0);
+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;
- return 0;
+ /* 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;
}
- 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;
+ /* 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;
}
- RFALSE(tb->rnum[0],
- "PAP-12065: bad rnum parameter must be 0 (%d)", tb->rnum[0]);
- return 0;
+ 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 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 */
- )
+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 item_pos = PATH_LAST_POSITION(tb->tb_path); /* index into the array of item headers in S[0]
- of the affected item */
+ int n = B_NR_ITEMS(tbS0);
+ struct item_head *pasted;
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]);
+ 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);
+ }
- /* Make balance in case insert_size[0] < 0 */
- if (tb->insert_size[0] < 0)
- return balance_leaf_when_delete(tb, flag);
+ /* 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]);
- zeros_num = 0;
- if (flag == M_INSERT && !body)
- zeros_num = ih_item_len(ih);
+ if (!tb->pos_in_item) {
- 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(item_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] */
- buffer_info_init_left(tb, &bi);
- 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] */
- buffer_info_init_left(tb, &bi);
- 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(item_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 = 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 + 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, 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(item_head(tbS0, item_pos)),
- "PAP-12100: incorrect position to paste: item_len=%d, pos_in_item=%d",
- ih_item_len(item_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
- (item_head(tbS0, item_pos)));
- /* Append to body of item in L[0] */
- buffer_info_init_left(tb, &bi);
- leaf_paste_in_buffer
- (&bi, n + item_pos - ret_val, ih_item_len
- (item_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(item_head(tbS0, 0)),
- "PAP-12106: item length must be 0");
- RFALSE(comp_short_le_keys(leaf_key(tbS0, 0), leaf_key
- (tb->L[0], n + item_pos - ret_val)),
- "PAP-12107: items must be of the same file");
- if (is_indirect_le_ih(item_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(item_head(tbS0, 0));
- set_le_key_k_offset(version, leaf_key(tbS0, 0),
- le_key_k_offset(version,leaf_key(tbS0, 0)) + temp_l);
- /* update left delimiting key */
- set_le_key_k_offset(version, internal_key(tb->CFL[0], tb->lkey[0]),
- le_key_k_offset(version, internal_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(leaf_key(tbS0, 0), 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(internal_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(leaf_key(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 = item_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] */
- buffer_info_init_left(tb, &bi);
- 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 = item_head(tb->L[0], n + item_pos - ret_val);
- if (is_direntry_le_ih(pasted))
- leaf_paste_entries(&bi, 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",
- "lnum > 0: unexpected 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);
+ 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);
}
}
- /* 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] */
- buffer_info_init_right(tb, &bi);
- 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] */
- buffer_info_init_right(tb, &bi);
- 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;
+ if (is_indirect_le_ih(pasted))
+ set_ih_free_space(pasted, 0);
+ tb->zeroes_num = tb->insert_size[0] = 0;
+}
- 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(item_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 = ih_entry_count(item_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;
- buffer_info_init_right(tb, &bi);
- leaf_paste_in_buffer(&bi, 0, paste_entry_position, tb->insert_size[0], body, zeros_num);
- /* paste entry */
- leaf_paste_entries(&bi, 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
- (item_head(tbS0, item_pos)),
- "PAP-12155: invalid position to paste. ih_item_len=%d, pos_in_item=%d",
- pos_in_item, ih_item_len
- (item_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(item_head(tb->R[0], 0));
- if (is_indirect_le_key(version, leaf_key(tb->R[0], 0))) {
- temp_rem = n_rem << (tb->tb_sb->s_blocksize_bits - UNFM_P_SHIFT);
- }
- set_le_key_k_offset(version, leaf_key(tb->R[0], 0),
- le_key_k_offset(version, leaf_key(tb->R[0], 0)) + temp_rem);
- set_le_key_k_offset(version, internal_key(tb->CFR[0], tb->rkey[0]),
- le_key_k_offset(version, internal_key(tb->CFR[0], tb->rkey[0])) + temp_rem);
- }
-/* k_offset (leaf_key(tb->R[0],0)) += n_rem;
- k_offset (internal_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] */
- buffer_info_init_right(tb, &bi);
- 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(item_head(tb->R[0], 0))) {
-#if 0
- RFALSE(n_rem,
- "PAP-12160: paste more than one unformatted node pointer");
-#endif
- set_ih_free_space(item_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) {
- buffer_info_init_right(tb, &bi);
- 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 = item_head(tb->R[0], item_pos - n + tb->rnum[0]);
- if (is_direntry_le_ih(pasted) && pos_in_item >= 0) {
- leaf_paste_entries(&bi, 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",
- "rnum > 0: unexpected mode: %s(%d)",
- (flag == M_DELETE) ? "DELETE" : ((flag == M_CUT) ? "CUT" : "UNKNOWN"), flag);
- }
+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;
}
- /* 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]);
+ /* pasted item or part of it falls to R[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 */
+ 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);
+}
- 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);
+/* 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;
}
- reiserfs_invalidate_buffer(tb, tbS0);
- return 0;
+ 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]);
}
- /* 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;
+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(!snum[i], "PAP-12200: snum[%d] == %d. Must be > 0", i,
- snum[i]);
+ 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 */
- S_new[i] = get_FEB(tb);
+ tb->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 */
- buffer_info_init_bh(tb, &bi, S_new[i]);
-
- 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] */
- buffer_info_init_bh(tb, &bi, S_new[i]);
- 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] */
+ 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]);
+ }
+}
- leaf_move_items(LEAF_FROM_S_TO_SNEW, tb,
- snum[i], sbytes[i], S_new[i]);
- }
- break;
+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);
- 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");
-
- aux_ih = item_head(tbS0, item_pos);
- if (is_direntry_le_ih(aux_ih)) {
- /* 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 */
- buffer_info_init_bh(tb, &bi, S_new[i]);
- 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, 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(item_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] */
- buffer_info_init_bh(tb, &bi, S_new[i]);
- 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 = item_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 leaf_mi;
- struct item_head *pasted;
+ /* 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);
-#ifdef CONFIG_REISERFS_CHECK
- struct item_head *ih_check = item_head(tbS0, item_pos);
-
- if (!is_direntry_le_ih(ih_check)
- && (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 /* CONFIG_REISERFS_CHECK */
-
- leaf_mi = leaf_move_items(LEAF_FROM_S_TO_SNEW,
- tb, snum[i],
- sbytes[i],
- 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, S_new[i]);
- leaf_paste_in_buffer(&bi,
- item_pos - n + snum[i],
- pos_in_item,
- tb->insert_size[0],
- body, zeros_num);
-
- pasted = item_head(S_new[i], item_pos - n + snum[i]);
- if (is_direntry_le_ih(pasted)) {
- leaf_paste_entries(&bi,
- 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] */
+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;
- 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",
- "blknum > 2: unexpected mode: %s(%d)",
- (flag == M_DELETE) ? "DELETE" : ((flag == M_CUT) ? "CUT" : "UNKNOWN"), flag);
+ 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);
}
- memcpy(insert_key + i, leaf_key(S_new[i], 0), KEY_SIZE);
- insert_ptr[i] = S_new[i];
+ tb->insert_size[0] = 0;
+ }
+}
- 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]);
+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;
}
- /* 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] */
+ /* regular object */
- switch (flag) {
- case M_INSERT: /* insert item into S[0] */
- buffer_info_init_tbS0(tb, &bi);
- leaf_insert_into_buf(&bi, item_pos, ih, body,
- zeros_num);
+ 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 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;
+ if (is_indirect_le_ih(pasted))
+ set_ih_free_space(pasted, 0);
- case M_PASTE:{ /* append item in S[0] */
- struct item_head *pasted;
-
- pasted = item_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 */
- buffer_info_init_tbS0(tb, &bi);
- leaf_paste_in_buffer(&bi, item_pos, pos_in_item,
- tb->insert_size[0], body,
- zeros_num);
-
- /* paste entry */
- leaf_paste_entries(&bi, 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]);
- buffer_info_init_tbS0(tb, &bi);
- 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;
- }
+ 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 /* CONFIG_REISERFS_CHECK */
-
- }
- } /* case M_PASTE: */
+ 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");
"PAP-12290", "insert_size is still not 0 (%d)",
tb->insert_size[0]);
}
-#endif /* CONFIG_REISERFS_CHECK */
+#endif
+
+ /* Leaf level of the tree is balanced (end of balance_leaf) */
return 0;
-} /* Leaf level of the tree is balanced (end of balance_leaf) */
+}
/* Make empty node */
void make_empty_node(struct buffer_info *bi)
return tb->used[i];
}
-/* This is now used because reiserfs_free_block has to be able to
-** schedule.
-*/
+/* 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;
"mount point.");
}
- /* double check that buffers that we will modify are unlocked. (fix_nodes should already have
- prepped all of these for us). */
+ /*
+ * 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]");
#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....
+/*
+ * 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 */
+ /* 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");*/
+ /*
+ 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;
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_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++;
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 */
+/*
+ * 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;
return;
}
- atomic_inc(&(fs_generation(tb->tb_sb)));
+ 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. */
+ /*
+ * 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);
/* 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);
+ child_pos = balance_internal(tb, h, child_pos, insert_key,
+ insert_ptr);
do_balance_completed(tb);
-
}
projects / cascardo / linux.git / blobdiff