/* * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README */ /* * Written by Anatoly P. Pinchuk pap@namesys.botik.ru * Programm System Institute * Pereslavl-Zalessky Russia */ #include #include #include #include #include "reiserfs.h" #include #include /* Does the buffer contain a disk block which is in the tree. */ inline int B_IS_IN_TREE(const struct buffer_head *bh) { RFALSE(B_LEVEL(bh) > MAX_HEIGHT, "PAP-1010: block (%b) has too big level (%z)", bh, bh); return (B_LEVEL(bh) != FREE_LEVEL); } /* to get item head in le form */ inline void copy_item_head(struct item_head *to, const struct item_head *from) { memcpy(to, from, IH_SIZE); } /* * k1 is pointer to on-disk structure which is stored in little-endian * form. k2 is pointer to cpu variable. For key of items of the same * object this returns 0. * Returns: -1 if key1 < key2 * 0 if key1 == key2 * 1 if key1 > key2 */ inline int comp_short_keys(const struct reiserfs_key *le_key, const struct cpu_key *cpu_key) { __u32 n; n = le32_to_cpu(le_key->k_dir_id); if (n < cpu_key->on_disk_key.k_dir_id) return -1; if (n > cpu_key->on_disk_key.k_dir_id) return 1; n = le32_to_cpu(le_key->k_objectid); if (n < cpu_key->on_disk_key.k_objectid) return -1; if (n > cpu_key->on_disk_key.k_objectid) return 1; return 0; } /* * k1 is pointer to on-disk structure which is stored in little-endian * form. k2 is pointer to cpu variable. * Compare keys using all 4 key fields. * Returns: -1 if key1 < key2 0 * if key1 = key2 1 if key1 > key2 */ static inline int comp_keys(const struct reiserfs_key *le_key, const struct cpu_key *cpu_key) { int retval; retval = comp_short_keys(le_key, cpu_key); if (retval) return retval; if (le_key_k_offset(le_key_version(le_key), le_key) < cpu_key_k_offset(cpu_key)) return -1; if (le_key_k_offset(le_key_version(le_key), le_key) > cpu_key_k_offset(cpu_key)) return 1; if (cpu_key->key_length == 3) return 0; /* this part is needed only when tail conversion is in progress */ if (le_key_k_type(le_key_version(le_key), le_key) < cpu_key_k_type(cpu_key)) return -1; if (le_key_k_type(le_key_version(le_key), le_key) > cpu_key_k_type(cpu_key)) return 1; return 0; } inline int comp_short_le_keys(const struct reiserfs_key *key1, const struct reiserfs_key *key2) { __u32 *k1_u32, *k2_u32; int key_length = REISERFS_SHORT_KEY_LEN; k1_u32 = (__u32 *) key1; k2_u32 = (__u32 *) key2; for (; key_length--; ++k1_u32, ++k2_u32) { if (le32_to_cpu(*k1_u32) < le32_to_cpu(*k2_u32)) return -1; if (le32_to_cpu(*k1_u32) > le32_to_cpu(*k2_u32)) return 1; } return 0; } inline void le_key2cpu_key(struct cpu_key *to, const struct reiserfs_key *from) { int version; to->on_disk_key.k_dir_id = le32_to_cpu(from->k_dir_id); to->on_disk_key.k_objectid = le32_to_cpu(from->k_objectid); /* find out version of the key */ version = le_key_version(from); to->version = version; to->on_disk_key.k_offset = le_key_k_offset(version, from); to->on_disk_key.k_type = le_key_k_type(version, from); } /* * this does not say which one is bigger, it only returns 1 if keys * are not equal, 0 otherwise */ inline int comp_le_keys(const struct reiserfs_key *k1, const struct reiserfs_key *k2) { return memcmp(k1, k2, sizeof(struct reiserfs_key)); } /************************************************************************** * Binary search toolkit function * * Search for an item in the array by the item key * * Returns: 1 if found, 0 if not found; * * *pos = number of the searched element if found, else the * * number of the first element that is larger than key. * **************************************************************************/ /* * For those not familiar with binary search: lbound is the leftmost item * that it could be, rbound the rightmost item that it could be. We examine * the item halfway between lbound and rbound, and that tells us either * that we can increase lbound, or decrease rbound, or that we have found it, * or if lbound <= rbound that there are no possible items, and we have not * found it. With each examination we cut the number of possible items it * could be by one more than half rounded down, or we find it. */ static inline int bin_search(const void *key, /* Key to search for. */ const void *base, /* First item in the array. */ int num, /* Number of items in the array. */ /* * Item size in the array. searched. Lest the * reader be confused, note that this is crafted * as a general function, and when it is applied * specifically to the array of item headers in a * node, width is actually the item header size * not the item size. */ int width, int *pos /* Number of the searched for element. */ ) { int rbound, lbound, j; for (j = ((rbound = num - 1) + (lbound = 0)) / 2; lbound <= rbound; j = (rbound + lbound) / 2) switch (comp_keys ((struct reiserfs_key *)((char *)base + j * width), (struct cpu_key *)key)) { case -1: lbound = j + 1; continue; case 1: rbound = j - 1; continue; case 0: *pos = j; return ITEM_FOUND; /* Key found in the array. */ } /* * bin_search did not find given key, it returns position of key, * that is minimal and greater than the given one. */ *pos = lbound; return ITEM_NOT_FOUND; } /* Minimal possible key. It is never in the tree. */ const struct reiserfs_key MIN_KEY = { 0, 0, {{0, 0},} }; /* Maximal possible key. It is never in the tree. */ static const struct reiserfs_key MAX_KEY = { cpu_to_le32(0xffffffff), cpu_to_le32(0xffffffff), {{cpu_to_le32(0xffffffff), cpu_to_le32(0xffffffff)},} }; /* * Get delimiting key of the buffer by looking for it in the buffers in the * path, starting from the bottom of the path, and going upwards. We must * check the path's validity at each step. If the key is not in the path, * there is no delimiting key in the tree (buffer is first or last buffer * in tree), and in this case we return a special key, either MIN_KEY or * MAX_KEY. */ static inline const struct reiserfs_key *get_lkey(const struct treepath *chk_path, const struct super_block *sb) { int position, path_offset = chk_path->path_length; struct buffer_head *parent; RFALSE(path_offset < FIRST_PATH_ELEMENT_OFFSET, "PAP-5010: invalid offset in the path"); /* While not higher in path than first element. */ while (path_offset-- > FIRST_PATH_ELEMENT_OFFSET) { RFALSE(!buffer_uptodate (PATH_OFFSET_PBUFFER(chk_path, path_offset)), "PAP-5020: parent is not uptodate"); /* Parent at the path is not in the tree now. */ if (!B_IS_IN_TREE (parent = PATH_OFFSET_PBUFFER(chk_path, path_offset))) return &MAX_KEY; /* Check whether position in the parent is correct. */ if ((position = PATH_OFFSET_POSITION(chk_path, path_offset)) > B_NR_ITEMS(parent)) return &MAX_KEY; /* Check whether parent at the path really points to the child. */ if (B_N_CHILD_NUM(parent, position) != PATH_OFFSET_PBUFFER(chk_path, path_offset + 1)->b_blocknr) return &MAX_KEY; /* * Return delimiting key if position in the parent * is not equal to zero. */ if (position) return internal_key(parent, position - 1); } /* Return MIN_KEY if we are in the root of the buffer tree. */ if (PATH_OFFSET_PBUFFER(chk_path, FIRST_PATH_ELEMENT_OFFSET)-> b_blocknr == SB_ROOT_BLOCK(sb)) return &MIN_KEY; return &MAX_KEY; } /* Get delimiting key of the buffer at the path and its right neighbor. */ inline const struct reiserfs_key *get_rkey(const struct treepath *chk_path, const struct super_block *sb) { int position, path_offset = chk_path->path_length; struct buffer_head *parent; RFALSE(path_offset < FIRST_PATH_ELEMENT_OFFSET, "PAP-5030: invalid offset in the path"); while (path_offset-- > FIRST_PATH_ELEMENT_OFFSET) { RFALSE(!buffer_uptodate (PATH_OFFSET_PBUFFER(chk_path, path_offset)), "PAP-5040: parent is not uptodate"); /* Parent at the path is not in the tree now. */ if (!B_IS_IN_TREE (parent = PATH_OFFSET_PBUFFER(chk_path, path_offset))) return &MIN_KEY; /* Check whether position in the parent is correct. */ if ((position = PATH_OFFSET_POSITION(chk_path, path_offset)) > B_NR_ITEMS(parent)) return &MIN_KEY; /* * Check whether parent at the path really points * to the child. */ if (B_N_CHILD_NUM(parent, position) != PATH_OFFSET_PBUFFER(chk_path, path_offset + 1)->b_blocknr) return &MIN_KEY; /* * Return delimiting key if position in the parent * is not the last one. */ if (position != B_NR_ITEMS(parent)) return internal_key(parent, position); } /* Return MAX_KEY if we are in the root of the buffer tree. */ if (PATH_OFFSET_PBUFFER(chk_path, FIRST_PATH_ELEMENT_OFFSET)-> b_blocknr == SB_ROOT_BLOCK(sb)) return &MAX_KEY; return &MIN_KEY; } /* * Check whether a key is contained in the tree rooted from a buffer at a path. * This works by looking at the left and right delimiting keys for the buffer * in the last path_element in the path. These delimiting keys are stored * at least one level above that buffer in the tree. If the buffer is the * first or last node in the tree order then one of the delimiting keys may * be absent, and in this case get_lkey and get_rkey return a special key * which is MIN_KEY or MAX_KEY. */ static inline int key_in_buffer( /* Path which should be checked. */ struct treepath *chk_path, /* Key which should be checked. */ const struct cpu_key *key, struct super_block *sb ) { RFALSE(!key || chk_path->path_length < FIRST_PATH_ELEMENT_OFFSET || chk_path->path_length > MAX_HEIGHT, "PAP-5050: pointer to the key(%p) is NULL or invalid path length(%d)", key, chk_path->path_length); RFALSE(!PATH_PLAST_BUFFER(chk_path)->b_bdev, "PAP-5060: device must not be NODEV"); if (comp_keys(get_lkey(chk_path, sb), key) == 1) /* left delimiting key is bigger, that the key we look for */ return 0; /* if ( comp_keys(key, get_rkey(chk_path, sb)) != -1 ) */ if (comp_keys(get_rkey(chk_path, sb), key) != 1) /* key must be less than right delimitiing key */ return 0; return 1; } int reiserfs_check_path(struct treepath *p) { RFALSE(p->path_length != ILLEGAL_PATH_ELEMENT_OFFSET, "path not properly relsed"); return 0; } /* * Drop the reference to each buffer in a path and restore * dirty bits clean when preparing the buffer for the log. * This version should only be called from fix_nodes() */ void pathrelse_and_restore(struct super_block *sb, struct treepath *search_path) { int path_offset = search_path->path_length; RFALSE(path_offset < ILLEGAL_PATH_ELEMENT_OFFSET, "clm-4000: invalid path offset"); while (path_offset > ILLEGAL_PATH_ELEMENT_OFFSET) { struct buffer_head *bh; bh = PATH_OFFSET_PBUFFER(search_path, path_offset--); reiserfs_restore_prepared_buffer(sb, bh); brelse(bh); } search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET; } /* Drop the reference to each buffer in a path */ void pathrelse(struct treepath *search_path) { int path_offset = search_path->path_length; RFALSE(path_offset < ILLEGAL_PATH_ELEMENT_OFFSET, "PAP-5090: invalid path offset"); while (path_offset > ILLEGAL_PATH_ELEMENT_OFFSET) brelse(PATH_OFFSET_PBUFFER(search_path, path_offset--)); search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET; } static int is_leaf(char *buf, int blocksize, struct buffer_head *bh) { struct block_head *blkh; struct item_head *ih; int used_space; int prev_location; int i; int nr; blkh = (struct block_head *)buf; if (blkh_level(blkh) != DISK_LEAF_NODE_LEVEL) { reiserfs_warning(NULL, "reiserfs-5080", "this should be caught earlier"); return 0; } nr = blkh_nr_item(blkh); if (nr < 1 || nr > ((blocksize - BLKH_SIZE) / (IH_SIZE + MIN_ITEM_LEN))) { /* item number is too big or too small */ reiserfs_warning(NULL, "reiserfs-5081", "nr_item seems wrong: %z", bh); return 0; } ih = (struct item_head *)(buf + BLKH_SIZE) + nr - 1; used_space = BLKH_SIZE + IH_SIZE * nr + (blocksize - ih_location(ih)); /* free space does not match to calculated amount of use space */ if (used_space != blocksize - blkh_free_space(blkh)) { reiserfs_warning(NULL, "reiserfs-5082", "free space seems wrong: %z", bh); return 0; } /* * FIXME: it is_leaf will hit performance too much - we may have * return 1 here */ /* check tables of item heads */ ih = (struct item_head *)(buf + BLKH_SIZE); prev_location = blocksize; for (i = 0; i < nr; i++, ih++) { if (le_ih_k_type(ih) == TYPE_ANY) { reiserfs_warning(NULL, "reiserfs-5083", "wrong item type for item %h", ih); return 0; } if (ih_location(ih) >= blocksize || ih_location(ih) < IH_SIZE * nr) { reiserfs_warning(NULL, "reiserfs-5084", "item location seems wrong: %h", ih); return 0; } if (ih_item_len(ih) < 1 || ih_item_len(ih) > MAX_ITEM_LEN(blocksize)) { reiserfs_warning(NULL, "reiserfs-5085", "item length seems wrong: %h", ih); return 0; } if (prev_location - ih_location(ih) != ih_item_len(ih)) { reiserfs_warning(NULL, "reiserfs-5086", "item location seems wrong " "(second one): %h", ih); return 0; } prev_location = ih_location(ih); } /* one may imagine many more checks */ return 1; } /* returns 1 if buf looks like an internal node, 0 otherwise */ static int is_internal(char *buf, int blocksize, struct buffer_head *bh) { struct block_head *blkh; int nr; int used_space; blkh = (struct block_head *)buf; nr = blkh_level(blkh); if (nr <= DISK_LEAF_NODE_LEVEL || nr > MAX_HEIGHT) { /* this level is not possible for internal nodes */ reiserfs_warning(NULL, "reiserfs-5087", "this should be caught earlier"); return 0; } nr = blkh_nr_item(blkh); /* for internal which is not root we might check min number of keys */ if (nr > (blocksize - BLKH_SIZE - DC_SIZE) / (KEY_SIZE + DC_SIZE)) { reiserfs_warning(NULL, "reiserfs-5088", "number of key seems wrong: %z", bh); return 0; } used_space = BLKH_SIZE + KEY_SIZE * nr + DC_SIZE * (nr + 1); if (used_space != blocksize - blkh_free_space(blkh)) { reiserfs_warning(NULL, "reiserfs-5089", "free space seems wrong: %z", bh); return 0; } /* one may imagine many more checks */ return 1; } /* * make sure that bh contains formatted node of reiserfs tree of * 'level'-th level */ static int is_tree_node(struct buffer_head *bh, int level) { if (B_LEVEL(bh) != level) { reiserfs_warning(NULL, "reiserfs-5090", "node level %d does " "not match to the expected one %d", B_LEVEL(bh), level); return 0; } if (level == DISK_LEAF_NODE_LEVEL) return is_leaf(bh->b_data, bh->b_size, bh); return is_internal(bh->b_data, bh->b_size, bh); } #define SEARCH_BY_KEY_READA 16 /* * The function is NOT SCHEDULE-SAFE! * It might unlock the write lock if we needed to wait for a block * to be read. Note that in this case it won't recover the lock to avoid * high contention resulting from too much lock requests, especially * the caller (search_by_key) will perform other schedule-unsafe * operations just after calling this function. * * @return depth of lock to be restored after read completes */ static int search_by_key_reada(struct super_block *s, struct buffer_head **bh, b_blocknr_t *b, int num) { int i, j; int depth = -1; for (i = 0; i < num; i++) { bh[i] = sb_getblk(s, b[i]); } /* * We are going to read some blocks on which we * have a reference. It's safe, though we might be * reading blocks concurrently changed if we release * the lock. But it's still fine because we check later * if the tree changed */ for (j = 0; j < i; j++) { /* * note, this needs attention if we are getting rid of the BKL * you have to make sure the prepared bit isn't set on this * buffer */ if (!buffer_uptodate(bh[j])) { if (depth == -1) depth = reiserfs_write_unlock_nested(s); ll_rw_block(REQ_OP_READ, REQ_RAHEAD, 1, bh + j); } brelse(bh[j]); } return depth; } /* * This function fills up the path from the root to the leaf as it * descends the tree looking for the key. It uses reiserfs_bread to * try to find buffers in the cache given their block number. If it * does not find them in the cache it reads them from disk. For each * node search_by_key finds using reiserfs_bread it then uses * bin_search to look through that node. bin_search will find the * position of the block_number of the next node if it is looking * through an internal node. If it is looking through a leaf node * bin_search will find the position of the item which has key either * equal to given key, or which is the maximal key less than the given * key. search_by_key returns a path that must be checked for the * correctness of the top of the path but need not be checked for the * correctness of the bottom of the path */ /* * search_by_key - search for key (and item) in stree * @sb: superblock * @key: pointer to key to search for * @search_path: Allocated and initialized struct treepath; Returned filled * on success. * @stop_level: How far down the tree to search, Use DISK_LEAF_NODE_LEVEL to * stop at leaf level. * * The function is NOT SCHEDULE-SAFE! */ int search_by_key(struct super_block *sb, const struct cpu_key *key, struct treepath *search_path, int stop_level) { b_blocknr_t block_number; int expected_level; struct buffer_head *bh; struct path_element *last_element; int node_level, retval; int right_neighbor_of_leaf_node; int fs_gen; struct buffer_head *reada_bh[SEARCH_BY_KEY_READA]; b_blocknr_t reada_blocks[SEARCH_BY_KEY_READA]; int reada_count = 0; #ifdef CONFIG_REISERFS_CHECK int repeat_counter = 0; #endif PROC_INFO_INC(sb, search_by_key); /* * As we add each node to a path we increase its count. This means * that we must be careful to release all nodes in a path before we * either discard the path struct or re-use the path struct, as we * do here. */ pathrelse(search_path); right_neighbor_of_leaf_node = 0; /* * With each iteration of this loop we search through the items in the * current node, and calculate the next current node(next path element) * for the next iteration of this loop.. */ block_number = SB_ROOT_BLOCK(sb); expected_level = -1; while (1) { #ifdef CONFIG_REISERFS_CHECK if (!(++repeat_counter % 50000)) reiserfs_warning(sb, "PAP-5100", "%s: there were %d iterations of " "while loop looking for key %K", current->comm, repeat_counter, key); #endif /* prep path to have another element added to it. */ last_element = PATH_OFFSET_PELEMENT(search_path, ++search_path->path_length); fs_gen = get_generation(sb); /* * Read the next tree node, and set the last element * in the path to have a pointer to it. */ if ((bh = last_element->pe_buffer = sb_getblk(sb, block_number))) { /* * We'll need to drop the lock if we encounter any * buffers that need to be read. If all of them are * already up to date, we don't need to drop the lock. */ int depth = -1; if (!buffer_uptodate(bh) && reada_count > 1) depth = search_by_key_reada(sb, reada_bh, reada_blocks, reada_count); if (!buffer_uptodate(bh) && depth == -1) depth = reiserfs_write_unlock_nested(sb); ll_rw_block(REQ_OP_READ, 0, 1, &bh); wait_on_buffer(bh); if (depth != -1) reiserfs_write_lock_nested(sb, depth); if (!buffer_uptodate(bh)) goto io_error; } else { io_error: search_path->path_length--; pathrelse(search_path); return IO_ERROR; } reada_count = 0; if (expected_level == -1) expected_level = SB_TREE_HEIGHT(sb); expected_level--; /* * It is possible that schedule occurred. We must check * whether the key to search is still in the tree rooted * from the current buffer. If not then repeat search * from the root. */ if (fs_changed(fs_gen, sb) && (!B_IS_IN_TREE(bh) || B_LEVEL(bh) != expected_level || !key_in_buffer(search_path, key, sb))) { PROC_INFO_INC(sb, search_by_key_fs_changed); PROC_INFO_INC(sb, search_by_key_restarted); PROC_INFO_INC(sb, sbk_restarted[expected_level - 1]); pathrelse(search_path); /* * Get the root block number so that we can * repeat the search starting from the root. */ block_number = SB_ROOT_BLOCK(sb); expected_level = -1; right_neighbor_of_leaf_node = 0; /* repeat search from the root */ continue; } /* * only check that the key is in the buffer if key is not * equal to the MAX_KEY. Latter case is only possible in * "finish_unfinished()" processing during mount. */ RFALSE(comp_keys(&MAX_KEY, key) && !key_in_buffer(search_path, key, sb), "PAP-5130: key is not in the buffer"); #ifdef CONFIG_REISERFS_CHECK if (REISERFS_SB(sb)->cur_tb) { print_cur_tb("5140"); reiserfs_panic(sb, "PAP-5140", "schedule occurred in do_balance!"); } #endif /* * make sure, that the node contents look like a node of * certain level */ if (!is_tree_node(bh, expected_level)) { reiserfs_error(sb, "vs-5150", "invalid format found in block %ld. " "Fsck?", bh->b_blocknr); pathrelse(search_path); return IO_ERROR; } /* ok, we have acquired next formatted node in the tree */ node_level = B_LEVEL(bh); PROC_INFO_BH_STAT(sb, bh, node_level - 1); RFALSE(node_level < stop_level, "vs-5152: tree level (%d) is less than stop level (%d)", node_level, stop_level); retval = bin_search(key, item_head(bh, 0), B_NR_ITEMS(bh), (node_level == DISK_LEAF_NODE_LEVEL) ? IH_SIZE : KEY_SIZE, &last_element->pe_position); if (node_level == stop_level) { return retval; } /* we are not in the stop level */ /* * item has been found, so we choose the pointer which * is to the right of the found one */ if (retval == ITEM_FOUND) last_element->pe_position++; /* * if item was not found we choose the position which is to * the left of the found item. This requires no code, * bin_search did it already. */ /* * So we have chosen a position in the current node which is * an internal node. Now we calculate child block number by * position in the node. */ block_number = B_N_CHILD_NUM(bh, last_element->pe_position); /* * if we are going to read leaf nodes, try for read * ahead as well */ if ((search_path->reada & PATH_READA) && node_level == DISK_LEAF_NODE_LEVEL + 1) { int pos = last_element->pe_position; int limit = B_NR_ITEMS(bh); struct reiserfs_key *le_key; if (search_path->reada & PATH_READA_BACK) limit = 0; while (reada_count < SEARCH_BY_KEY_READA) { if (pos == limit) break; reada_blocks[reada_count++] = B_N_CHILD_NUM(bh, pos); if (search_path->reada & PATH_READA_BACK) pos--; else pos++; /* * check to make sure we're in the same object */ le_key = internal_key(bh, pos); if (le32_to_cpu(le_key->k_objectid) != key->on_disk_key.k_objectid) { break; } } } } } /* * Form the path to an item and position in this item which contains * file byte defined by key. If there is no such item * corresponding to the key, we point the path to the item with * maximal key less than key, and *pos_in_item is set to one * past the last entry/byte in the item. If searching for entry in a * directory item, and it is not found, *pos_in_item is set to one * entry more than the entry with maximal key which is less than the * sought key. * * Note that if there is no entry in this same node which is one more, * then we point to an imaginary entry. for direct items, the * position is in units of bytes, for indirect items the position is * in units of blocknr entries, for directory items the position is in * units of directory entries. */ /* The function is NOT SCHEDULE-SAFE! */ int search_for_position_by_key(struct super_block *sb, /* Key to search (cpu variable) */ const struct cpu_key *p_cpu_key, /* Filled up by this function. */ struct treepath *search_path) { struct item_head *p_le_ih; /* pointer to on-disk structure */ int blk_size; loff_t item_offset, offset; struct reiserfs_dir_entry de; int retval; /* If searching for directory entry. */ if (is_direntry_cpu_key(p_cpu_key)) return search_by_entry_key(sb, p_cpu_key, search_path, &de); /* If not searching for directory entry. */ /* If item is found. */ retval = search_item(sb, p_cpu_key, search_path); if (retval == IO_ERROR) return retval; if (retval == ITEM_FOUND) { RFALSE(!ih_item_len (item_head (PATH_PLAST_BUFFER(search_path), PATH_LAST_POSITION(search_path))), "PAP-5165: item length equals zero"); pos_in_item(search_path) = 0; return POSITION_FOUND; } RFALSE(!PATH_LAST_POSITION(search_path), "PAP-5170: position equals zero"); /* Item is not found. Set path to the previous item. */ p_le_ih = item_head(PATH_PLAST_BUFFER(search_path), --PATH_LAST_POSITION(search_path)); blk_size = sb->s_blocksize; if (comp_short_keys(&p_le_ih->ih_key, p_cpu_key)) return FILE_NOT_FOUND; /* FIXME: quite ugly this far */ item_offset = le_ih_k_offset(p_le_ih); offset = cpu_key_k_offset(p_cpu_key); /* Needed byte is contained in the item pointed to by the path. */ if (item_offset <= offset && item_offset + op_bytes_number(p_le_ih, blk_size) > offset) { pos_in_item(search_path) = offset - item_offset; if (is_indirect_le_ih(p_le_ih)) { pos_in_item(search_path) /= blk_size; } return POSITION_FOUND; } /* * Needed byte is not contained in the item pointed to by the * path. Set pos_in_item out of the item. */ if (is_indirect_le_ih(p_le_ih)) pos_in_item(search_path) = ih_item_len(p_le_ih) / UNFM_P_SIZE; else pos_in_item(search_path) = ih_item_len(p_le_ih); return POSITION_NOT_FOUND; } /* Compare given item and item pointed to by the path. */ int comp_items(const struct item_head *stored_ih, const struct treepath *path) { struct buffer_head *bh = PATH_PLAST_BUFFER(path); struct item_head *ih; /* Last buffer at the path is not in the tree. */ if (!B_IS_IN_TREE(bh)) return 1; /* Last path position is invalid. */ if (PATH_LAST_POSITION(path) >= B_NR_ITEMS(bh)) return 1; /* we need only to know, whether it is the same item */ ih = tp_item_head(path); return memcmp(stored_ih, ih, IH_SIZE); } /* unformatted nodes are not logged anymore, ever. This is safe now */ #define held_by_others(bh) (atomic_read(&(bh)->b_count) > 1) /* block can not be forgotten as it is in I/O or held by someone */ #define block_in_use(bh) (buffer_locked(bh) || (held_by_others(bh))) /* prepare for delete or cut of direct item */ static inline int prepare_for_direct_item(struct treepath *path, struct item_head *le_ih, struct inode *inode, loff_t new_file_length, int *cut_size) { loff_t round_len; if (new_file_length == max_reiserfs_offset(inode)) { /* item has to be deleted */ *cut_size = -(IH_SIZE + ih_item_len(le_ih)); return M_DELETE; } /* new file gets truncated */ if (get_inode_item_key_version(inode) == KEY_FORMAT_3_6) { round_len = ROUND_UP(new_file_length); /* this was new_file_length < le_ih ... */ if (round_len < le_ih_k_offset(le_ih)) { *cut_size = -(IH_SIZE + ih_item_len(le_ih)); return M_DELETE; /* Delete this item. */ } /* Calculate first position and size for cutting from item. */ pos_in_item(path) = round_len - (le_ih_k_offset(le_ih) - 1); *cut_size = -(ih_item_len(le_ih) - pos_in_item(path)); return M_CUT; /* Cut from this item. */ } /* old file: items may have any length */ if (new_file_length < le_ih_k_offset(le_ih)) { *cut_size = -(IH_SIZE + ih_item_len(le_ih)); return M_DELETE; /* Delete this item. */ } /* Calculate first position and size for cutting from item. */ *cut_size = -(ih_item_len(le_ih) - (pos_in_item(path) = new_file_length + 1 - le_ih_k_offset(le_ih))); return M_CUT; /* Cut from this item. */ } static inline int prepare_for_direntry_item(struct treepath *path, struct item_head *le_ih, struct inode *inode, loff_t new_file_length, int *cut_size) { if (le_ih_k_offset(le_ih) == DOT_OFFSET && new_file_length == max_reiserfs_offset(inode)) { RFALSE(ih_entry_count(le_ih) != 2, "PAP-5220: incorrect empty directory item (%h)", le_ih); *cut_size = -(IH_SIZE + ih_item_len(le_ih)); /* Delete the directory item containing "." and ".." entry. */ return M_DELETE; } if (ih_entry_count(le_ih) == 1) { /* * Delete the directory item such as there is one record only * in this item */ *cut_size = -(IH_SIZE + ih_item_len(le_ih)); return M_DELETE; } /* Cut one record from the directory item. */ *cut_size = -(DEH_SIZE + entry_length(get_last_bh(path), le_ih, pos_in_item(path))); return M_CUT; } #define JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD (2 * JOURNAL_PER_BALANCE_CNT + 1) /* * If the path points to a directory or direct item, calculate mode * and the size cut, for balance. * If the path points to an indirect item, remove some number of its * unformatted nodes. * In case of file truncate calculate whether this item must be * deleted/truncated or last unformatted node of this item will be * converted to a direct item. * This function returns a determination of what balance mode the * calling function should employ. */ static char prepare_for_delete_or_cut(struct reiserfs_transaction_handle *th, struct inode *inode, struct treepath *path, const struct cpu_key *item_key, /* * Number of unformatted nodes * which were removed from end * of the file. */ int *removed, int *cut_size, /* MAX_KEY_OFFSET in case of delete. */ unsigned long long new_file_length ) { struct super_block *sb = inode->i_sb; struct item_head *p_le_ih = tp_item_head(path); struct buffer_head *bh = PATH_PLAST_BUFFER(path); BUG_ON(!th->t_trans_id); /* Stat_data item. */ if (is_statdata_le_ih(p_le_ih)) { RFALSE(new_file_length != max_reiserfs_offset(inode), "PAP-5210: mode must be M_DELETE"); *cut_size = -(IH_SIZE + ih_item_len(p_le_ih)); return M_DELETE; } /* Directory item. */ if (is_direntry_le_ih(p_le_ih)) return prepare_for_direntry_item(path, p_le_ih, inode, new_file_length, cut_size); /* Direct item. */ if (is_direct_le_ih(p_le_ih)) return prepare_for_direct_item(path, p_le_ih, inode, new_file_length, cut_size); /* Case of an indirect item. */ { int blk_size = sb->s_blocksize; struct item_head s_ih; int need_re_search; int delete = 0; int result = M_CUT; int pos = 0; if ( new_file_length == max_reiserfs_offset (inode) ) { /* * prepare_for_delete_or_cut() is called by * reiserfs_delete_item() */ new_file_length = 0; delete = 1; } do { need_re_search = 0; *cut_size = 0; bh = PATH_PLAST_BUFFER(path); copy_item_head(&s_ih, tp_item_head(path)); pos = I_UNFM_NUM(&s_ih); while (le_ih_k_offset (&s_ih) + (pos - 1) * blk_size > new_file_length) { __le32 *unfm; __u32 block; /* * Each unformatted block deletion may involve * one additional bitmap block into the transaction, * thereby the initial journal space reservation * might not be enough. */ if (!delete && (*cut_size) != 0 && reiserfs_transaction_free_space(th) < JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD) break; unfm = (__le32 *)ih_item_body(bh, &s_ih) + pos - 1; block = get_block_num(unfm, 0); if (block != 0) { reiserfs_prepare_for_journal(sb, bh, 1); put_block_num(unfm, 0, 0); journal_mark_dirty(th, bh); reiserfs_free_block(th, inode, block, 1); } reiserfs_cond_resched(sb); if (item_moved (&s_ih, path)) { need_re_search = 1; break; } pos --; (*removed)++; (*cut_size) -= UNFM_P_SIZE; if (pos == 0) { (*cut_size) -= IH_SIZE; result = M_DELETE; break; } } /* * a trick. If the buffer has been logged, this will * do nothing. If we've broken the loop without logging * it, it will restore the buffer */ reiserfs_restore_prepared_buffer(sb, bh); } while (need_re_search && search_for_position_by_key(sb, item_key, path) == POSITION_FOUND); pos_in_item(path) = pos * UNFM_P_SIZE; if (*cut_size == 0) { /* * Nothing was cut. maybe convert last unformatted node to the * direct item? */ result = M_CONVERT; } return result; } } /* Calculate number of bytes which will be deleted or cut during balance */ static int calc_deleted_bytes_number(struct tree_balance *tb, char mode) { int del_size; struct item_head *p_le_ih = tp_item_head(tb->tb_path); if (is_statdata_le_ih(p_le_ih)) return 0; del_size = (mode == M_DELETE) ? ih_item_len(p_le_ih) : -tb->insert_size[0]; if (is_direntry_le_ih(p_le_ih)) { /* * return EMPTY_DIR_SIZE; We delete emty directories only. * we can't use EMPTY_DIR_SIZE, as old format dirs have a * different empty size. ick. FIXME, is this right? */ return del_size; } if (is_indirect_le_ih(p_le_ih)) del_size = (del_size / UNFM_P_SIZE) * (PATH_PLAST_BUFFER(tb->tb_path)->b_size); return del_size; } static void init_tb_struct(struct reiserfs_transaction_handle *th, struct tree_balance *tb, struct super_block *sb, struct treepath *path, int size) { BUG_ON(!th->t_trans_id); memset(tb, '\0', sizeof(struct tree_balance)); tb->transaction_handle = th; tb->tb_sb = sb; tb->tb_path = path; PATH_OFFSET_PBUFFER(path, ILLEGAL_PATH_ELEMENT_OFFSET) = NULL; PATH_OFFSET_POSITION(path, ILLEGAL_PATH_ELEMENT_OFFSET) = 0; tb->insert_size[0] = size; } void padd_item(char *item, int total_length, int length) { int i; for (i = total_length; i > length;) item[--i] = 0; } #ifdef REISERQUOTA_DEBUG char key2type(struct reiserfs_key *ih) { if (is_direntry_le_key(2, ih)) return 'd'; if (is_direct_le_key(2, ih)) return 'D'; if (is_indirect_le_key(2, ih)) return 'i'; if (is_statdata_le_key(2, ih)) return 's'; return 'u'; } char head2type(struct item_head *ih) { if (is_direntry_le_ih(ih)) return 'd'; if (is_direct_le_ih(ih)) return 'D'; if (is_indirect_le_ih(ih)) return 'i'; if (is_statdata_le_ih(ih)) return 's'; return 'u'; } #endif /* * Delete object item. * th - active transaction handle * path - path to the deleted item * item_key - key to search for the deleted item * indode - used for updating i_blocks and quotas * un_bh - NULL or unformatted node pointer */ int reiserfs_delete_item(struct reiserfs_transaction_handle *th, struct treepath *path, const struct cpu_key *item_key, struct inode *inode, struct buffer_head *un_bh) { struct super_block *sb = inode->i_sb; struct tree_balance s_del_balance; struct item_head s_ih; struct item_head *q_ih; int quota_cut_bytes; int ret_value, del_size, removed; int depth; #ifdef CONFIG_REISERFS_CHECK char mode; int iter = 0; #endif BUG_ON(!th->t_trans_id); init_tb_struct(th, &s_del_balance, sb, path, 0 /*size is unknown */ ); while (1) { removed = 0; #ifdef CONFIG_REISERFS_CHECK iter++; mode = #endif prepare_for_delete_or_cut(th, inode, path, item_key, &removed, &del_size, max_reiserfs_offset(inode)); RFALSE(mode != M_DELETE, "PAP-5320: mode must be M_DELETE"); copy_item_head(&s_ih, tp_item_head(path)); s_del_balance.insert_size[0] = del_size; ret_value = fix_nodes(M_DELETE, &s_del_balance, NULL, NULL); if (ret_value != REPEAT_SEARCH) break; PROC_INFO_INC(sb, delete_item_restarted); /* file system changed, repeat search */ ret_value = search_for_position_by_key(sb, item_key, path); if (ret_value == IO_ERROR) break; if (ret_value == FILE_NOT_FOUND) { reiserfs_warning(sb, "vs-5340", "no items of the file %K found", item_key); break; } } /* while (1) */ if (ret_value != CARRY_ON) { unfix_nodes(&s_del_balance); return 0; } /* reiserfs_delete_item returns item length when success */ ret_value = calc_deleted_bytes_number(&s_del_balance, M_DELETE); q_ih = tp_item_head(path); quota_cut_bytes = ih_item_len(q_ih); /* * hack so the quota code doesn't have to guess if the file has a * tail. On tail insert, we allocate quota for 1 unformatted node. * We test the offset because the tail might have been * split into multiple items, and we only want to decrement for * the unfm node once */ if (!S_ISLNK(inode->i_mode) && is_direct_le_ih(q_ih)) { if ((le_ih_k_offset(q_ih) & (sb->s_blocksize - 1)) == 1) { quota_cut_bytes = sb->s_blocksize + UNFM_P_SIZE; } else { quota_cut_bytes = 0; } } if (un_bh) { int off; char *data; /* * We are in direct2indirect conversion, so move tail contents * to the unformatted node */ /* * note, we do the copy before preparing the buffer because we * don't care about the contents of the unformatted node yet. * the only thing we really care about is the direct item's * data is in the unformatted node. * * Otherwise, we would have to call * reiserfs_prepare_for_journal on the unformatted node, * which might schedule, meaning we'd have to loop all the * way back up to the start of the while loop. * * The unformatted node must be dirtied later on. We can't be * sure here if the entire tail has been deleted yet. * * un_bh is from the page cache (all unformatted nodes are * from the page cache) and might be a highmem page. So, we * can't use un_bh->b_data. * -clm */ data = kmap_atomic(un_bh->b_page); off = ((le_ih_k_offset(&s_ih) - 1) & (PAGE_SIZE - 1)); memcpy(data + off, ih_item_body(PATH_PLAST_BUFFER(path), &s_ih), ret_value); kunmap_atomic(data); } /* Perform balancing after all resources have been collected at once. */ do_balance(&s_del_balance, NULL, NULL, M_DELETE); #ifdef REISERQUOTA_DEBUG reiserfs_debug(sb, REISERFS_DEBUG_CODE, "reiserquota delete_item(): freeing %u, id=%u type=%c", quota_cut_bytes, inode->i_uid, head2type(&s_ih)); #endif depth = reiserfs_write_unlock_nested(inode->i_sb); dquot_free_space_nodirty(inode, quota_cut_bytes); reiserfs_write_lock_nested(inode->i_sb, depth); /* Return deleted body length */ return ret_value; } /* * Summary Of Mechanisms For Handling Collisions Between Processes: * * deletion of the body of the object is performed by iput(), with the * result that if multiple processes are operating on a file, the * deletion of the body of the file is deferred until the last process * that has an open inode performs its iput(). * * writes and truncates are protected from collisions by use of * semaphores. * * creates, linking, and mknod are protected from collisions with other * processes by making the reiserfs_add_entry() the last step in the * creation, and then rolling back all changes if there was a collision. * - Hans */ /* this deletes item which never gets split */ void reiserfs_delete_solid_item(struct reiserfs_transaction_handle *th, struct inode *inode, struct reiserfs_key *key) { struct super_block *sb = th->t_super; struct tree_balance tb; INITIALIZE_PATH(path); int item_len = 0; int tb_init = 0; struct cpu_key cpu_key; int retval; int quota_cut_bytes = 0; BUG_ON(!th->t_trans_id); le_key2cpu_key(&cpu_key, key); while (1) { retval = search_item(th->t_super, &cpu_key, &path); if (retval == IO_ERROR) { reiserfs_error(th->t_super, "vs-5350", "i/o failure occurred trying " "to delete %K", &cpu_key); break; } if (retval != ITEM_FOUND) { pathrelse(&path); /* * No need for a warning, if there is just no free * space to insert '..' item into the * newly-created subdir */ if (! ((unsigned long long) GET_HASH_VALUE(le_key_k_offset (le_key_version(key), key)) == 0 && (unsigned long long) GET_GENERATION_NUMBER(le_key_k_offset (le_key_version(key), key)) == 1)) reiserfs_warning(th->t_super, "vs-5355", "%k not found", key); break; } if (!tb_init) { tb_init = 1; item_len = ih_item_len(tp_item_head(&path)); init_tb_struct(th, &tb, th->t_super, &path, -(IH_SIZE + item_len)); } quota_cut_bytes = ih_item_len(tp_item_head(&path)); retval = fix_nodes(M_DELETE, &tb, NULL, NULL); if (retval == REPEAT_SEARCH) { PROC_INFO_INC(th->t_super, delete_solid_item_restarted); continue; } if (retval == CARRY_ON) { do_balance(&tb, NULL, NULL, M_DELETE); /* * Should we count quota for item? (we don't * count quotas for save-links) */ if (inode) { int depth; #ifdef REISERQUOTA_DEBUG reiserfs_debug(th->t_super, REISERFS_DEBUG_CODE, "reiserquota delete_solid_item(): freeing %u id=%u type=%c", quota_cut_bytes, inode->i_uid, key2type(key)); #endif depth = reiserfs_write_unlock_nested(sb); dquot_free_space_nodirty(inode, quota_cut_bytes); reiserfs_write_lock_nested(sb, depth); } break; } /* IO_ERROR, NO_DISK_SPACE, etc */ reiserfs_warning(th->t_super, "vs-5360", "could not delete %K due to fix_nodes failure", &cpu_key); unfix_nodes(&tb); break; } reiserfs_check_path(&path); } int reiserfs_delete_object(struct reiserfs_transaction_handle *th, struct inode *inode) { int err; inode->i_size = 0; BUG_ON(!th->t_trans_id); /* for directory this deletes item containing "." and ".." */ err = reiserfs_do_truncate(th, inode, NULL, 0 /*no timestamp updates */ ); if (err) return err; #if defined( USE_INODE_GENERATION_COUNTER ) if (!old_format_only(th->t_super)) { __le32 *inode_generation; inode_generation = &REISERFS_SB(th->t_super)->s_rs->s_inode_generation; le32_add_cpu(inode_generation, 1); } /* USE_INODE_GENERATION_COUNTER */ #endif reiserfs_delete_solid_item(th, inode, INODE_PKEY(inode)); return err; } static void unmap_buffers(struct page *page, loff_t pos) { struct buffer_head *bh; struct buffer_head *head; struct buffer_head *next; unsigned long tail_index; unsigned long cur_index; if (page) { if (page_has_buffers(page)) { tail_index = pos & (PAGE_SIZE - 1); cur_index = 0; head = page_buffers(page); bh = head; do { next = bh->b_this_page; /* * we want to unmap the buffers that contain * the tail, and all the buffers after it * (since the tail must be at the end of the * file). We don't want to unmap file data * before the tail, since it might be dirty * and waiting to reach disk */ cur_index += bh->b_size; if (cur_index > tail_index) { reiserfs_unmap_buffer(bh); } bh = next; } while (bh != head); } } } static int maybe_indirect_to_direct(struct reiserfs_transaction_handle *th, struct inode *inode, struct page *page, struct treepath *path, const struct cpu_key *item_key, loff_t new_file_size, char *mode) { struct super_block *sb = inode->i_sb; int block_size = sb->s_blocksize; int cut_bytes; BUG_ON(!th->t_trans_id); BUG_ON(new_file_size != inode->i_size); /* * the page being sent in could be NULL if there was an i/o error * reading in the last block. The user will hit problems trying to * read the file, but for now we just skip the indirect2direct */ if (atomic_read(&inode->i_count) > 1 || !tail_has_to_be_packed(inode) || !page || (REISERFS_I(inode)->i_flags & i_nopack_mask)) { /* leave tail in an unformatted node */ *mode = M_SKIP_BALANCING; cut_bytes = block_size - (new_file_size & (block_size - 1)); pathrelse(path); return cut_bytes; } /* Perform the conversion to a direct_item. */ return indirect2direct(th, inode, page, path, item_key, new_file_size, mode); } /* * we did indirect_to_direct conversion. And we have inserted direct * item successesfully, but there were no disk space to cut unfm * pointer being converted. Therefore we have to delete inserted * direct item(s) */ static void indirect_to_direct_roll_back(struct reiserfs_transaction_handle *th, struct inode *inode, struct treepath *path) { struct cpu_key tail_key; int tail_len; int removed; BUG_ON(!th->t_trans_id); make_cpu_key(&tail_key, inode, inode->i_size + 1, TYPE_DIRECT, 4); tail_key.key_length = 4; tail_len = (cpu_key_k_offset(&tail_key) & (inode->i_sb->s_blocksize - 1)) - 1; while (tail_len) { /* look for the last byte of the tail */ if (search_for_position_by_key(inode->i_sb, &tail_key, path) == POSITION_NOT_FOUND) reiserfs_panic(inode->i_sb, "vs-5615", "found invalid item"); RFALSE(path->pos_in_item != ih_item_len(tp_item_head(path)) - 1, "vs-5616: appended bytes found"); PATH_LAST_POSITION(path)--; removed = reiserfs_delete_item(th, path, &tail_key, inode, NULL /*unbh not needed */ ); RFALSE(removed <= 0 || removed > tail_len, "vs-5617: there was tail %d bytes, removed item length %d bytes", tail_len, removed); tail_len -= removed; set_cpu_key_k_offset(&tail_key, cpu_key_k_offset(&tail_key) - removed); } reiserfs_warning(inode->i_sb, "reiserfs-5091", "indirect_to_direct " "conversion has been rolled back due to " "lack of disk space"); mark_inode_dirty(inode); } /* (Truncate or cut entry) or delete object item. Returns < 0 on failure */ int reiserfs_cut_from_item(struct reiserfs_transaction_handle *th, struct treepath *path, struct cpu_key *item_key, struct inode *inode, struct page *page, loff_t new_file_size) { struct super_block *sb = inode->i_sb; /* * Every function which is going to call do_balance must first * create a tree_balance structure. Then it must fill up this * structure by using the init_tb_struct and fix_nodes functions. * After that we can make tree balancing. */ struct tree_balance s_cut_balance; struct item_head *p_le_ih; int cut_size = 0; /* Amount to be cut. */ int ret_value = CARRY_ON; int removed = 0; /* Number of the removed unformatted nodes. */ int is_inode_locked = 0; char mode; /* Mode of the balance. */ int retval2 = -1; int quota_cut_bytes; loff_t tail_pos = 0; int depth; BUG_ON(!th->t_trans_id); init_tb_struct(th, &s_cut_balance, inode->i_sb, path, cut_size); /* * Repeat this loop until we either cut the item without needing * to balance, or we fix_nodes without schedule occurring */ while (1) { /* * Determine the balance mode, position of the first byte to * be cut, and size to be cut. In case of the indirect item * free unformatted nodes which are pointed to by the cut * pointers. */ mode = prepare_for_delete_or_cut(th, inode, path, item_key, &removed, &cut_size, new_file_size); if (mode == M_CONVERT) { /* * convert last unformatted node to direct item or * leave tail in the unformatted node */ RFALSE(ret_value != CARRY_ON, "PAP-5570: can not convert twice"); ret_value = maybe_indirect_to_direct(th, inode, page, path, item_key, new_file_size, &mode); if (mode == M_SKIP_BALANCING) /* tail has been left in the unformatted node */ return ret_value; is_inode_locked = 1; /* * removing of last unformatted node will * change value we have to return to truncate. * Save it */ retval2 = ret_value; /* * So, we have performed the first part of the * conversion: * inserting the new direct item. Now we are * removing the last unformatted node pointer. * Set key to search for it. */ set_cpu_key_k_type(item_key, TYPE_INDIRECT); item_key->key_length = 4; new_file_size -= (new_file_size & (sb->s_blocksize - 1)); tail_pos = new_file_size; set_cpu_key_k_offset(item_key, new_file_size + 1); if (search_for_position_by_key (sb, item_key, path) == POSITION_NOT_FOUND) { print_block(PATH_PLAST_BUFFER(path), 3, PATH_LAST_POSITION(path) - 1, PATH_LAST_POSITION(path) + 1); reiserfs_panic(sb, "PAP-5580", "item to " "convert does not exist (%K)", item_key); } continue; } if (cut_size == 0) { pathrelse(path); return 0; } s_cut_balance.insert_size[0] = cut_size; ret_value = fix_nodes(mode, &s_cut_balance, NULL, NULL); if (ret_value != REPEAT_SEARCH) break; PROC_INFO_INC(sb, cut_from_item_restarted); ret_value = search_for_position_by_key(sb, item_key, path); if (ret_value == POSITION_FOUND) continue; reiserfs_warning(sb, "PAP-5610", "item %K not found", item_key); unfix_nodes(&s_cut_balance); return (ret_value == IO_ERROR) ? -EIO : -ENOENT; } /* while */ /* check fix_nodes results (IO_ERROR or NO_DISK_SPACE) */ if (ret_value != CARRY_ON) { if (is_inode_locked) { /* * FIXME: this seems to be not needed: we are always * able to cut item */ indirect_to_direct_roll_back(th, inode, path); } if (ret_value == NO_DISK_SPACE) reiserfs_warning(sb, "reiserfs-5092", "NO_DISK_SPACE"); unfix_nodes(&s_cut_balance); return -EIO; } /* go ahead and perform balancing */ RFALSE(mode == M_PASTE || mode == M_INSERT, "invalid mode"); /* Calculate number of bytes that need to be cut from the item. */ quota_cut_bytes = (mode == M_DELETE) ? ih_item_len(tp_item_head(path)) : -s_cut_balance. insert_size[0]; if (retval2 == -1) ret_value = calc_deleted_bytes_number(&s_cut_balance, mode); else ret_value = retval2; /* * For direct items, we only change the quota when deleting the last * item. */ p_le_ih = tp_item_head(s_cut_balance.tb_path); if (!S_ISLNK(inode->i_mode) && is_direct_le_ih(p_le_ih)) { if (mode == M_DELETE && (le_ih_k_offset(p_le_ih) & (sb->s_blocksize - 1)) == 1) { /* FIXME: this is to keep 3.5 happy */ REISERFS_I(inode)->i_first_direct_byte = U32_MAX; quota_cut_bytes = sb->s_blocksize + UNFM_P_SIZE; } else { quota_cut_bytes = 0; } } #ifdef CONFIG_REISERFS_CHECK if (is_inode_locked) { struct item_head *le_ih = tp_item_head(s_cut_balance.tb_path); /* * we are going to complete indirect2direct conversion. Make * sure, that we exactly remove last unformatted node pointer * of the item */ if (!is_indirect_le_ih(le_ih)) reiserfs_panic(sb, "vs-5652", "item must be indirect %h", le_ih); if (mode == M_DELETE && ih_item_len(le_ih) != UNFM_P_SIZE) reiserfs_panic(sb, "vs-5653", "completing " "indirect2direct conversion indirect " "item %h being deleted must be of " "4 byte long", le_ih); if (mode == M_CUT && s_cut_balance.insert_size[0] != -UNFM_P_SIZE) { reiserfs_panic(sb, "vs-5654", "can not complete " "indirect2direct conversion of %h " "(CUT, insert_size==%d)", le_ih, s_cut_balance.insert_size[0]); } /* * it would be useful to make sure, that right neighboring * item is direct item of this file */ } #endif do_balance(&s_cut_balance, NULL, NULL, mode); if (is_inode_locked) { /* * we've done an indirect->direct conversion. when the * data block was freed, it was removed from the list of * blocks that must be flushed before the transaction * commits, make sure to unmap and invalidate it */ unmap_buffers(page, tail_pos); REISERFS_I(inode)->i_flags &= ~i_pack_on_close_mask; } #ifdef REISERQUOTA_DEBUG reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE, "reiserquota cut_from_item(): freeing %u id=%u type=%c", quota_cut_bytes, inode->i_uid, '?'); #endif depth = reiserfs_write_unlock_nested(sb); dquot_free_space_nodirty(inode, quota_cut_bytes); reiserfs_write_lock_nested(sb, depth); return ret_value; } static void truncate_directory(struct reiserfs_transaction_handle *th, struct inode *inode) { BUG_ON(!th->t_trans_id); if (inode->i_nlink) reiserfs_error(inode->i_sb, "vs-5655", "link count != 0"); set_le_key_k_offset(KEY_FORMAT_3_5, INODE_PKEY(inode), DOT_OFFSET); set_le_key_k_type(KEY_FORMAT_3_5, INODE_PKEY(inode), TYPE_DIRENTRY); reiserfs_delete_solid_item(th, inode, INODE_PKEY(inode)); reiserfs_update_sd(th, inode); set_le_key_k_offset(KEY_FORMAT_3_5, INODE_PKEY(inode), SD_OFFSET); set_le_key_k_type(KEY_FORMAT_3_5, INODE_PKEY(inode), TYPE_STAT_DATA); } /* * Truncate file to the new size. Note, this must be called with a * transaction already started */ int reiserfs_do_truncate(struct reiserfs_transaction_handle *th, struct inode *inode, /* ->i_size contains new size */ struct page *page, /* up to date for last block */ /* * when it is called by file_release to convert * the tail - no timestamps should be updated */ int update_timestamps ) { INITIALIZE_PATH(s_search_path); /* Path to the current object item. */ struct item_head *p_le_ih; /* Pointer to an item header. */ /* Key to search for a previous file item. */ struct cpu_key s_item_key; loff_t file_size, /* Old file size. */ new_file_size; /* New file size. */ int deleted; /* Number of deleted or truncated bytes. */ int retval; int err = 0; BUG_ON(!th->t_trans_id); if (! (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode))) return 0; /* deletion of directory - no need to update timestamps */ if (S_ISDIR(inode->i_mode)) { truncate_directory(th, inode); return 0; } /* Get new file size. */ new_file_size = inode->i_size; /* FIXME: note, that key type is unimportant here */ make_cpu_key(&s_item_key, inode, max_reiserfs_offset(inode), TYPE_DIRECT, 3); retval = search_for_position_by_key(inode->i_sb, &s_item_key, &s_search_path); if (retval == IO_ERROR) { reiserfs_error(inode->i_sb, "vs-5657", "i/o failure occurred trying to truncate %K", &s_item_key); err = -EIO; goto out; } if (retval == POSITION_FOUND || retval == FILE_NOT_FOUND) { reiserfs_error(inode->i_sb, "PAP-5660", "wrong result %d of search for %K", retval, &s_item_key); err = -EIO; goto out; } s_search_path.pos_in_item--; /* Get real file size (total length of all file items) */ p_le_ih = tp_item_head(&s_search_path); if (is_statdata_le_ih(p_le_ih)) file_size = 0; else { loff_t offset = le_ih_k_offset(p_le_ih); int bytes = op_bytes_number(p_le_ih, inode->i_sb->s_blocksize); /* * this may mismatch with real file size: if last direct item * had no padding zeros and last unformatted node had no free * space, this file would have this file size */ file_size = offset + bytes - 1; } /* * are we doing a full truncate or delete, if so * kick in the reada code */ if (new_file_size == 0) s_search_path.reada = PATH_READA | PATH_READA_BACK; if (file_size == 0 || file_size < new_file_size) { goto update_and_out; } /* Update key to search for the last file item. */ set_cpu_key_k_offset(&s_item_key, file_size); do { /* Cut or delete file item. */ deleted = reiserfs_cut_from_item(th, &s_search_path, &s_item_key, inode, page, new_file_size); if (deleted < 0) { reiserfs_warning(inode->i_sb, "vs-5665", "reiserfs_cut_from_item failed"); reiserfs_check_path(&s_search_path); return 0; } RFALSE(deleted > file_size, "PAP-5670: reiserfs_cut_from_item: too many bytes deleted: deleted %d, file_size %lu, item_key %K", deleted, file_size, &s_item_key); /* Change key to search the last file item. */ file_size -= deleted; set_cpu_key_k_offset(&s_item_key, file_size); /* * While there are bytes to truncate and previous * file item is presented in the tree. */ /* * This loop could take a really long time, and could log * many more blocks than a transaction can hold. So, we do * a polite journal end here, and if the transaction needs * ending, we make sure the file is consistent before ending * the current trans and starting a new one */ if (journal_transaction_should_end(th, 0) || reiserfs_transaction_free_space(th) <= JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD) { pathrelse(&s_search_path); if (update_timestamps) { inode->i_mtime = current_time(inode); inode->i_ctime = current_time(inode); } reiserfs_update_sd(th, inode); err = journal_end(th); if (err) goto out; err = journal_begin(th, inode->i_sb, JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD + JOURNAL_PER_BALANCE_CNT * 4) ; if (err) goto out; reiserfs_update_inode_transaction(inode); } } while (file_size > ROUND_UP(new_file_size) && search_for_position_by_key(inode->i_sb, &s_item_key, &s_search_path) == POSITION_FOUND); RFALSE(file_size > ROUND_UP(new_file_size), "PAP-5680: truncate did not finish: new_file_size %lld, current %lld, oid %d", new_file_size, file_size, s_item_key.on_disk_key.k_objectid); update_and_out: if (update_timestamps) { /* this is truncate, not file closing */ inode->i_mtime = current_time(inode); inode->i_ctime = current_time(inode); } reiserfs_update_sd(th, inode); out: pathrelse(&s_search_path); return err; } #ifdef CONFIG_REISERFS_CHECK /* this makes sure, that we __append__, not overwrite or add holes */ static void check_research_for_paste(struct treepath *path, const struct cpu_key *key) { struct item_head *found_ih = tp_item_head(path); if (is_direct_le_ih(found_ih)) { if (le_ih_k_offset(found_ih) + op_bytes_number(found_ih, get_last_bh(path)->b_size) != cpu_key_k_offset(key) || op_bytes_number(found_ih, get_last_bh(path)->b_size) != pos_in_item(path)) reiserfs_panic(NULL, "PAP-5720", "found direct item " "%h or position (%d) does not match " "to key %K", found_ih, pos_in_item(path), key); } if (is_indirect_le_ih(found_ih)) { if (le_ih_k_offset(found_ih) + op_bytes_number(found_ih, get_last_bh(path)->b_size) != cpu_key_k_offset(key) || I_UNFM_NUM(found_ih) != pos_in_item(path) || get_ih_free_space(found_ih) != 0) reiserfs_panic(NULL, "PAP-5730", "found indirect " "item (%h) or position (%d) does not " "match to key (%K)", found_ih, pos_in_item(path), key); } } #endif /* config reiserfs check */ /* * Paste bytes to the existing item. * Returns bytes number pasted into the item. */ int reiserfs_paste_into_item(struct reiserfs_transaction_handle *th, /* Path to the pasted item. */ struct treepath *search_path, /* Key to search for the needed item. */ const struct cpu_key *key, /* Inode item belongs to */ struct inode *inode, /* Pointer to the bytes to paste. */ const char *body, /* Size of pasted bytes. */ int pasted_size) { struct super_block *sb = inode->i_sb; struct tree_balance s_paste_balance; int retval; int fs_gen; int depth; BUG_ON(!th->t_trans_id); fs_gen = get_generation(inode->i_sb); #ifdef REISERQUOTA_DEBUG reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE, "reiserquota paste_into_item(): allocating %u id=%u type=%c", pasted_size, inode->i_uid, key2type(&key->on_disk_key)); #endif depth = reiserfs_write_unlock_nested(sb); retval = dquot_alloc_space_nodirty(inode, pasted_size); reiserfs_write_lock_nested(sb, depth); if (retval) { pathrelse(search_path); return retval; } init_tb_struct(th, &s_paste_balance, th->t_super, search_path, pasted_size); #ifdef DISPLACE_NEW_PACKING_LOCALITIES s_paste_balance.key = key->on_disk_key; #endif /* DQUOT_* can schedule, must check before the fix_nodes */ if (fs_changed(fs_gen, inode->i_sb)) { goto search_again; } while ((retval = fix_nodes(M_PASTE, &s_paste_balance, NULL, body)) == REPEAT_SEARCH) { search_again: /* file system changed while we were in the fix_nodes */ PROC_INFO_INC(th->t_super, paste_into_item_restarted); retval = search_for_position_by_key(th->t_super, key, search_path); if (retval == IO_ERROR) { retval = -EIO; goto error_out; } if (retval == POSITION_FOUND) { reiserfs_warning(inode->i_sb, "PAP-5710", "entry or pasted byte (%K) exists", key); retval = -EEXIST; goto error_out; } #ifdef CONFIG_REISERFS_CHECK check_research_for_paste(search_path, key); #endif } /* * Perform balancing after all resources are collected by fix_nodes, * and accessing them will not risk triggering schedule. */ if (retval == CARRY_ON) { do_balance(&s_paste_balance, NULL /*ih */ , body, M_PASTE); return 0; } retval = (retval == NO_DISK_SPACE) ? -ENOSPC : -EIO; error_out: /* this also releases the path */ unfix_nodes(&s_paste_balance); #ifdef REISERQUOTA_DEBUG reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE, "reiserquota paste_into_item(): freeing %u id=%u type=%c", pasted_size, inode->i_uid, key2type(&key->on_disk_key)); #endif depth = reiserfs_write_unlock_nested(sb); dquot_free_space_nodirty(inode, pasted_size); reiserfs_write_lock_nested(sb, depth); return retval; } /* * Insert new item into the buffer at the path. * th - active transaction handle * path - path to the inserted item * ih - pointer to the item header to insert * body - pointer to the bytes to insert */ int reiserfs_insert_item(struct reiserfs_transaction_handle *th, struct treepath *path, const struct cpu_key *key, struct item_head *ih, struct inode *inode, const char *body) { struct tree_balance s_ins_balance; int retval; int fs_gen = 0; int quota_bytes = 0; BUG_ON(!th->t_trans_id); if (inode) { /* Do we count quotas for item? */ int depth; fs_gen = get_generation(inode->i_sb); quota_bytes = ih_item_len(ih); /* * hack so the quota code doesn't have to guess * if the file has a tail, links are always tails, * so there's no guessing needed */ if (!S_ISLNK(inode->i_mode) && is_direct_le_ih(ih)) quota_bytes = inode->i_sb->s_blocksize + UNFM_P_SIZE; #ifdef REISERQUOTA_DEBUG reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE, "reiserquota insert_item(): allocating %u id=%u type=%c", quota_bytes, inode->i_uid, head2type(ih)); #endif /* * We can't dirty inode here. It would be immediately * written but appropriate stat item isn't inserted yet... */ depth = reiserfs_write_unlock_nested(inode->i_sb); retval = dquot_alloc_space_nodirty(inode, quota_bytes); reiserfs_write_lock_nested(inode->i_sb, depth); if (retval) { pathrelse(path); return retval; } } init_tb_struct(th, &s_ins_balance, th->t_super, path, IH_SIZE + ih_item_len(ih)); #ifdef DISPLACE_NEW_PACKING_LOCALITIES s_ins_balance.key = key->on_disk_key; #endif /* * DQUOT_* can schedule, must check to be sure calling * fix_nodes is safe */ if (inode && fs_changed(fs_gen, inode->i_sb)) { goto search_again; } while ((retval = fix_nodes(M_INSERT, &s_ins_balance, ih, body)) == REPEAT_SEARCH) { search_again: /* file system changed while we were in the fix_nodes */ PROC_INFO_INC(th->t_super, insert_item_restarted); retval = search_item(th->t_super, key, path); if (retval == IO_ERROR) { retval = -EIO; goto error_out; } if (retval == ITEM_FOUND) { reiserfs_warning(th->t_super, "PAP-5760", "key %K already exists in the tree", key); retval = -EEXIST; goto error_out; } } /* make balancing after all resources will be collected at a time */ if (retval == CARRY_ON) { do_balance(&s_ins_balance, ih, body, M_INSERT); return 0; } retval = (retval == NO_DISK_SPACE) ? -ENOSPC : -EIO; error_out: /* also releases the path */ unfix_nodes(&s_ins_balance); #ifdef REISERQUOTA_DEBUG reiserfs_debug(th->t_super, REISERFS_DEBUG_CODE, "reiserquota insert_item(): freeing %u id=%u type=%c", quota_bytes, inode->i_uid, head2type(ih)); #endif if (inode) { int depth = reiserfs_write_unlock_nested(inode->i_sb); dquot_free_space_nodirty(inode, quota_bytes); reiserfs_write_lock_nested(inode->i_sb, depth); } return retval; }