1c1d7c514SDavid Sterba // SPDX-License-Identifier: GPL-2.0 26cbd5570SChris Mason /* 36cbd5570SChris Mason * Copyright (C) 2007 Oracle. All rights reserved. 46cbd5570SChris Mason */ 56cbd5570SChris Mason 69b569ea0SJosef Bacik #include "messages.h" 762e2749eSChris Mason #include "ctree.h" 862e2749eSChris Mason #include "disk-io.h" 9e089f05cSChris Mason #include "transaction.h" 1007e81dc9SJosef Bacik #include "accessors.h" 1162e2749eSChris Mason 12d352ac68SChris Mason /* 13d352ac68SChris Mason * insert a name into a directory, doing overflow properly if there is a hash 14d352ac68SChris Mason * collision. data_size indicates how big the item inserted should be. On 15d352ac68SChris Mason * success a struct btrfs_dir_item pointer is returned, otherwise it is 16d352ac68SChris Mason * an ERR_PTR. 17d352ac68SChris Mason * 18d352ac68SChris Mason * The name is not copied into the dir item, you have to do that yourself. 19d352ac68SChris Mason */ 2035b7e476SChris Mason static struct btrfs_dir_item *insert_with_overflow(struct btrfs_trans_handle 2135b7e476SChris Mason *trans, 227e38180eSChris Mason struct btrfs_root *root, 237e38180eSChris Mason struct btrfs_path *path, 247e38180eSChris Mason struct btrfs_key *cpu_key, 25e06afa83SChris Mason u32 data_size, 26e06afa83SChris Mason const char *name, 27e06afa83SChris Mason int name_len) 287fcde0e3SChris Mason { 292ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 307fcde0e3SChris Mason int ret; 317e38180eSChris Mason char *ptr; 325f39d397SChris Mason struct extent_buffer *leaf; 337fcde0e3SChris Mason 347fcde0e3SChris Mason ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size); 357e38180eSChris Mason if (ret == -EEXIST) { 36e06afa83SChris Mason struct btrfs_dir_item *di; 372ff7e61eSJeff Mahoney di = btrfs_match_dir_item_name(fs_info, path, name, name_len); 38e06afa83SChris Mason if (di) 39e06afa83SChris Mason return ERR_PTR(-EEXIST); 40c71dd880SDavid Sterba btrfs_extend_item(path, data_size); 41143bede5SJeff Mahoney } else if (ret < 0) 4254aa1f4dSChris Mason return ERR_PTR(ret); 437e38180eSChris Mason WARN_ON(ret > 0); 445f39d397SChris Mason leaf = path->nodes[0]; 457e38180eSChris Mason ptr = btrfs_item_ptr(leaf, path->slots[0], char); 463212fa14SJosef Bacik ASSERT(data_size <= btrfs_item_size(leaf, path->slots[0])); 473212fa14SJosef Bacik ptr += btrfs_item_size(leaf, path->slots[0]) - data_size; 487e38180eSChris Mason return (struct btrfs_dir_item *)ptr; 497fcde0e3SChris Mason } 507fcde0e3SChris Mason 51d352ac68SChris Mason /* 52d352ac68SChris Mason * xattrs work a lot like directories, this inserts an xattr item 53d352ac68SChris Mason * into the tree 54d352ac68SChris Mason */ 555103e947SJosef Bacik int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans, 56f34f57a3SYan, Zheng struct btrfs_root *root, 57f34f57a3SYan, Zheng struct btrfs_path *path, u64 objectid, 58f34f57a3SYan, Zheng const char *name, u16 name_len, 59f34f57a3SYan, Zheng const void *data, u16 data_len) 605103e947SJosef Bacik { 615103e947SJosef Bacik int ret = 0; 625103e947SJosef Bacik struct btrfs_dir_item *dir_item; 635103e947SJosef Bacik unsigned long name_ptr, data_ptr; 645103e947SJosef Bacik struct btrfs_key key, location; 655103e947SJosef Bacik struct btrfs_disk_key disk_key; 665103e947SJosef Bacik struct extent_buffer *leaf; 675103e947SJosef Bacik u32 data_size; 685103e947SJosef Bacik 69b9d04c60SDavid Sterba if (name_len + data_len > BTRFS_MAX_XATTR_SIZE(root->fs_info)) 70b9d04c60SDavid Sterba return -ENOSPC; 71f34f57a3SYan, Zheng 72f34f57a3SYan, Zheng key.objectid = objectid; 73962a298fSDavid Sterba key.type = BTRFS_XATTR_ITEM_KEY; 74df68b8a7SDavid Miller key.offset = btrfs_name_hash(name, name_len); 755103e947SJosef Bacik 765103e947SJosef Bacik data_size = sizeof(*dir_item) + name_len + data_len; 775103e947SJosef Bacik dir_item = insert_with_overflow(trans, root, path, &key, data_size, 785103e947SJosef Bacik name, name_len); 79fa09200bSJosef Bacik if (IS_ERR(dir_item)) 80fa09200bSJosef Bacik return PTR_ERR(dir_item); 815103e947SJosef Bacik memset(&location, 0, sizeof(location)); 825103e947SJosef Bacik 835103e947SJosef Bacik leaf = path->nodes[0]; 845103e947SJosef Bacik btrfs_cpu_key_to_disk(&disk_key, &location); 855103e947SJosef Bacik btrfs_set_dir_item_key(leaf, dir_item, &disk_key); 86*94a48aefSOmar Sandoval btrfs_set_dir_flags(leaf, dir_item, BTRFS_FT_XATTR); 875103e947SJosef Bacik btrfs_set_dir_name_len(leaf, dir_item, name_len); 88e02119d5SChris Mason btrfs_set_dir_transid(leaf, dir_item, trans->transid); 895103e947SJosef Bacik btrfs_set_dir_data_len(leaf, dir_item, data_len); 905103e947SJosef Bacik name_ptr = (unsigned long)(dir_item + 1); 915103e947SJosef Bacik data_ptr = (unsigned long)((char *)name_ptr + name_len); 925103e947SJosef Bacik 935103e947SJosef Bacik write_extent_buffer(leaf, name, name_ptr, name_len); 945103e947SJosef Bacik write_extent_buffer(leaf, data, data_ptr, data_len); 955103e947SJosef Bacik btrfs_mark_buffer_dirty(path->nodes[0]); 965103e947SJosef Bacik 975103e947SJosef Bacik return ret; 985103e947SJosef Bacik } 995103e947SJosef Bacik 100d352ac68SChris Mason /* 101d352ac68SChris Mason * insert a directory item in the tree, doing all the magic for 102d352ac68SChris Mason * both indexes. 'dir' indicates which objectid to insert it into, 103d352ac68SChris Mason * 'location' is the key to stuff into the directory item, 'type' is the 104d352ac68SChris Mason * type of the inode we're pointing to, and 'index' is the sequence number 105d352ac68SChris Mason * to use for the second index (if one is created). 10679787eaaSJeff Mahoney * Will return 0 or -ENOMEM 107d352ac68SChris Mason */ 108e43eec81SSweet Tea Dorminy int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, 1096db75318SSweet Tea Dorminy const struct fscrypt_str *name, struct btrfs_inode *dir, 110684572dfSLu Fengqi struct btrfs_key *location, u8 type, u64 index) 11162e2749eSChris Mason { 11262e2749eSChris Mason int ret = 0; 113e06afa83SChris Mason int ret2 = 0; 114684572dfSLu Fengqi struct btrfs_root *root = dir->root; 1155caf2a00SChris Mason struct btrfs_path *path; 11662e2749eSChris Mason struct btrfs_dir_item *dir_item; 1175f39d397SChris Mason struct extent_buffer *leaf; 1185f39d397SChris Mason unsigned long name_ptr; 11962e2749eSChris Mason struct btrfs_key key; 1205f39d397SChris Mason struct btrfs_disk_key disk_key; 12162e2749eSChris Mason u32 data_size; 12262e2749eSChris Mason 1238e7611cfSNikolay Borisov key.objectid = btrfs_ino(dir); 124962a298fSDavid Sterba key.type = BTRFS_DIR_ITEM_KEY; 125e43eec81SSweet Tea Dorminy key.offset = btrfs_name_hash(name->name, name->len); 126b9473439SChris Mason 1275caf2a00SChris Mason path = btrfs_alloc_path(); 12816cdcec7SMiao Xie if (!path) 12916cdcec7SMiao Xie return -ENOMEM; 130b9473439SChris Mason 13116cdcec7SMiao Xie btrfs_cpu_key_to_disk(&disk_key, location); 13216cdcec7SMiao Xie 133e43eec81SSweet Tea Dorminy data_size = sizeof(*dir_item) + name->len; 134e06afa83SChris Mason dir_item = insert_with_overflow(trans, root, path, &key, data_size, 135e43eec81SSweet Tea Dorminy name->name, name->len); 1367e38180eSChris Mason if (IS_ERR(dir_item)) { 1377e38180eSChris Mason ret = PTR_ERR(dir_item); 138e06afa83SChris Mason if (ret == -EEXIST) 139e06afa83SChris Mason goto second_insert; 140c2db1073STsutomu Itoh goto out_free; 1417e38180eSChris Mason } 14262e2749eSChris Mason 143*94a48aefSOmar Sandoval if (IS_ENCRYPTED(&dir->vfs_inode)) 144*94a48aefSOmar Sandoval type |= BTRFS_FT_ENCRYPTED; 145*94a48aefSOmar Sandoval 1465f39d397SChris Mason leaf = path->nodes[0]; 1475f39d397SChris Mason btrfs_set_dir_item_key(leaf, dir_item, &disk_key); 148*94a48aefSOmar Sandoval btrfs_set_dir_flags(leaf, dir_item, type); 1495103e947SJosef Bacik btrfs_set_dir_data_len(leaf, dir_item, 0); 150e43eec81SSweet Tea Dorminy btrfs_set_dir_name_len(leaf, dir_item, name->len); 151e02119d5SChris Mason btrfs_set_dir_transid(leaf, dir_item, trans->transid); 1525f39d397SChris Mason name_ptr = (unsigned long)(dir_item + 1); 153c5739bbaSChris Mason 154e43eec81SSweet Tea Dorminy write_extent_buffer(leaf, name->name, name_ptr, name->len); 1555f39d397SChris Mason btrfs_mark_buffer_dirty(leaf); 1567e38180eSChris Mason 157e06afa83SChris Mason second_insert: 1587e38180eSChris Mason /* FIXME, use some real flag for selecting the extra index */ 1597e38180eSChris Mason if (root == root->fs_info->tree_root) { 1607e38180eSChris Mason ret = 0; 161c2db1073STsutomu Itoh goto out_free; 1627e38180eSChris Mason } 163b3b4aa74SDavid Sterba btrfs_release_path(path); 1647e38180eSChris Mason 165e43eec81SSweet Tea Dorminy ret2 = btrfs_insert_delayed_dir_index(trans, name->name, name->len, dir, 1664465c8b4SLu Fengqi &disk_key, type, index); 167c2db1073STsutomu Itoh out_free: 1685caf2a00SChris Mason btrfs_free_path(path); 169e06afa83SChris Mason if (ret) 17062e2749eSChris Mason return ret; 171e06afa83SChris Mason if (ret2) 172e06afa83SChris Mason return ret2; 173e06afa83SChris Mason return 0; 17462e2749eSChris Mason } 17562e2749eSChris Mason 176a7d1c5dcSMarcos Paulo de Souza static struct btrfs_dir_item *btrfs_lookup_match_dir( 177a7d1c5dcSMarcos Paulo de Souza struct btrfs_trans_handle *trans, 178a7d1c5dcSMarcos Paulo de Souza struct btrfs_root *root, struct btrfs_path *path, 179a7d1c5dcSMarcos Paulo de Souza struct btrfs_key *key, const char *name, 180a7d1c5dcSMarcos Paulo de Souza int name_len, int mod) 181a7d1c5dcSMarcos Paulo de Souza { 182a7d1c5dcSMarcos Paulo de Souza const int ins_len = (mod < 0 ? -1 : 0); 183a7d1c5dcSMarcos Paulo de Souza const int cow = (mod != 0); 184a7d1c5dcSMarcos Paulo de Souza int ret; 185a7d1c5dcSMarcos Paulo de Souza 186a7d1c5dcSMarcos Paulo de Souza ret = btrfs_search_slot(trans, root, key, path, ins_len, cow); 187a7d1c5dcSMarcos Paulo de Souza if (ret < 0) 188a7d1c5dcSMarcos Paulo de Souza return ERR_PTR(ret); 189a7d1c5dcSMarcos Paulo de Souza if (ret > 0) 190a7d1c5dcSMarcos Paulo de Souza return ERR_PTR(-ENOENT); 191a7d1c5dcSMarcos Paulo de Souza 192a7d1c5dcSMarcos Paulo de Souza return btrfs_match_dir_item_name(root->fs_info, path, name, name_len); 193a7d1c5dcSMarcos Paulo de Souza } 194a7d1c5dcSMarcos Paulo de Souza 195d352ac68SChris Mason /* 1968dcbc261SFilipe Manana * Lookup for a directory item by name. 1978dcbc261SFilipe Manana * 1988dcbc261SFilipe Manana * @trans: The transaction handle to use. Can be NULL if @mod is 0. 1998dcbc261SFilipe Manana * @root: The root of the target tree. 2008dcbc261SFilipe Manana * @path: Path to use for the search. 2018dcbc261SFilipe Manana * @dir: The inode number (objectid) of the directory. 2028dcbc261SFilipe Manana * @name: The name associated to the directory entry we are looking for. 2038dcbc261SFilipe Manana * @name_len: The length of the name. 2048dcbc261SFilipe Manana * @mod: Used to indicate if the tree search is meant for a read only 2058dcbc261SFilipe Manana * lookup, for a modification lookup or for a deletion lookup, so 2068dcbc261SFilipe Manana * its value should be 0, 1 or -1, respectively. 2078dcbc261SFilipe Manana * 2088dcbc261SFilipe Manana * Returns: NULL if the dir item does not exists, an error pointer if an error 2098dcbc261SFilipe Manana * happened, or a pointer to a dir item if a dir item exists for the given name. 210d352ac68SChris Mason */ 2117e38180eSChris Mason struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, 2127e38180eSChris Mason struct btrfs_root *root, 2137e38180eSChris Mason struct btrfs_path *path, u64 dir, 2146db75318SSweet Tea Dorminy const struct fscrypt_str *name, 2157e38180eSChris Mason int mod) 21662e2749eSChris Mason { 21762e2749eSChris Mason struct btrfs_key key; 218a7d1c5dcSMarcos Paulo de Souza struct btrfs_dir_item *di; 21962e2749eSChris Mason 22062e2749eSChris Mason key.objectid = dir; 221962a298fSDavid Sterba key.type = BTRFS_DIR_ITEM_KEY; 222e43eec81SSweet Tea Dorminy key.offset = btrfs_name_hash(name->name, name->len); 2235f39d397SChris Mason 224e43eec81SSweet Tea Dorminy di = btrfs_lookup_match_dir(trans, root, path, &key, name->name, 225e43eec81SSweet Tea Dorminy name->len, mod); 226a7d1c5dcSMarcos Paulo de Souza if (IS_ERR(di) && PTR_ERR(di) == -ENOENT) 2277e38180eSChris Mason return NULL; 2287fcde0e3SChris Mason 229a7d1c5dcSMarcos Paulo de Souza return di; 23062e2749eSChris Mason } 23162e2749eSChris Mason 2329c52057cSChris Mason int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir, 2336db75318SSweet Tea Dorminy const struct fscrypt_str *name) 2349c52057cSChris Mason { 2359c52057cSChris Mason int ret; 2369c52057cSChris Mason struct btrfs_key key; 2379c52057cSChris Mason struct btrfs_dir_item *di; 2389c52057cSChris Mason int data_size; 2399c52057cSChris Mason struct extent_buffer *leaf; 2409c52057cSChris Mason int slot; 2419c52057cSChris Mason struct btrfs_path *path; 2429c52057cSChris Mason 2439c52057cSChris Mason path = btrfs_alloc_path(); 2449c52057cSChris Mason if (!path) 2459c52057cSChris Mason return -ENOMEM; 2469c52057cSChris Mason 2479c52057cSChris Mason key.objectid = dir; 248962a298fSDavid Sterba key.type = BTRFS_DIR_ITEM_KEY; 249e43eec81SSweet Tea Dorminy key.offset = btrfs_name_hash(name->name, name->len); 2509c52057cSChris Mason 251e43eec81SSweet Tea Dorminy di = btrfs_lookup_match_dir(NULL, root, path, &key, name->name, 252e43eec81SSweet Tea Dorminy name->len, 0); 253a7d1c5dcSMarcos Paulo de Souza if (IS_ERR(di)) { 254a7d1c5dcSMarcos Paulo de Souza ret = PTR_ERR(di); 255a7d1c5dcSMarcos Paulo de Souza /* Nothing found, we're safe */ 256a7d1c5dcSMarcos Paulo de Souza if (ret == -ENOENT) { 2579c52057cSChris Mason ret = 0; 2589c52057cSChris Mason goto out; 2599c52057cSChris Mason } 2609c52057cSChris Mason 261a7d1c5dcSMarcos Paulo de Souza if (ret < 0) 262a7d1c5dcSMarcos Paulo de Souza goto out; 263a7d1c5dcSMarcos Paulo de Souza } 264a7d1c5dcSMarcos Paulo de Souza 2659c52057cSChris Mason /* we found an item, look for our name in the item */ 2669c52057cSChris Mason if (di) { 2679c52057cSChris Mason /* our exact name was found */ 2689c52057cSChris Mason ret = -EEXIST; 2699c52057cSChris Mason goto out; 2709c52057cSChris Mason } 2719c52057cSChris Mason 272e43eec81SSweet Tea Dorminy /* See if there is room in the item to insert this name. */ 273e43eec81SSweet Tea Dorminy data_size = sizeof(*di) + name->len; 2749c52057cSChris Mason leaf = path->nodes[0]; 2759c52057cSChris Mason slot = path->slots[0]; 2763212fa14SJosef Bacik if (data_size + btrfs_item_size(leaf, slot) + 277da17066cSJeff Mahoney sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(root->fs_info)) { 2789c52057cSChris Mason ret = -EOVERFLOW; 2799c52057cSChris Mason } else { 2809c52057cSChris Mason /* plenty of insertion room */ 2819c52057cSChris Mason ret = 0; 2829c52057cSChris Mason } 2839c52057cSChris Mason out: 2849c52057cSChris Mason btrfs_free_path(path); 2859c52057cSChris Mason return ret; 2869c52057cSChris Mason } 2879c52057cSChris Mason 288d352ac68SChris Mason /* 2898dcbc261SFilipe Manana * Lookup for a directory index item by name and index number. 290d352ac68SChris Mason * 2918dcbc261SFilipe Manana * @trans: The transaction handle to use. Can be NULL if @mod is 0. 2928dcbc261SFilipe Manana * @root: The root of the target tree. 2938dcbc261SFilipe Manana * @path: Path to use for the search. 2948dcbc261SFilipe Manana * @dir: The inode number (objectid) of the directory. 2958dcbc261SFilipe Manana * @index: The index number. 2968dcbc261SFilipe Manana * @name: The name associated to the directory entry we are looking for. 2978dcbc261SFilipe Manana * @name_len: The length of the name. 2988dcbc261SFilipe Manana * @mod: Used to indicate if the tree search is meant for a read only 2998dcbc261SFilipe Manana * lookup, for a modification lookup or for a deletion lookup, so 3008dcbc261SFilipe Manana * its value should be 0, 1 or -1, respectively. 3018dcbc261SFilipe Manana * 3028dcbc261SFilipe Manana * Returns: NULL if the dir index item does not exists, an error pointer if an 3038dcbc261SFilipe Manana * error happened, or a pointer to a dir item if the dir index item exists and 3048dcbc261SFilipe Manana * matches the criteria (name and index number). 305d352ac68SChris Mason */ 3067e38180eSChris Mason struct btrfs_dir_item * 3077e38180eSChris Mason btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans, 3087e38180eSChris Mason struct btrfs_root *root, 3097e38180eSChris Mason struct btrfs_path *path, u64 dir, 3106db75318SSweet Tea Dorminy u64 index, const struct fscrypt_str *name, int mod) 3117e38180eSChris Mason { 3128dcbc261SFilipe Manana struct btrfs_dir_item *di; 3137e38180eSChris Mason struct btrfs_key key; 3147e38180eSChris Mason 3157e38180eSChris Mason key.objectid = dir; 316962a298fSDavid Sterba key.type = BTRFS_DIR_INDEX_KEY; 3178dcbc261SFilipe Manana key.offset = index; 3187e38180eSChris Mason 319e43eec81SSweet Tea Dorminy di = btrfs_lookup_match_dir(trans, root, path, &key, name->name, 320e43eec81SSweet Tea Dorminy name->len, mod); 3218dcbc261SFilipe Manana if (di == ERR_PTR(-ENOENT)) 3228dcbc261SFilipe Manana return NULL; 3238dcbc261SFilipe Manana 3248dcbc261SFilipe Manana return di; 3257e38180eSChris Mason } 3267e38180eSChris Mason 3274df27c4dSYan, Zheng struct btrfs_dir_item * 328e43eec81SSweet Tea Dorminy btrfs_search_dir_index_item(struct btrfs_root *root, struct btrfs_path *path, 3296db75318SSweet Tea Dorminy u64 dirid, const struct fscrypt_str *name) 3304df27c4dSYan, Zheng { 3314df27c4dSYan, Zheng struct btrfs_dir_item *di; 3324df27c4dSYan, Zheng struct btrfs_key key; 3334df27c4dSYan, Zheng int ret; 3344df27c4dSYan, Zheng 3354df27c4dSYan, Zheng key.objectid = dirid; 3364df27c4dSYan, Zheng key.type = BTRFS_DIR_INDEX_KEY; 3374df27c4dSYan, Zheng key.offset = 0; 3384df27c4dSYan, Zheng 3399dcbe16fSGabriel Niebler btrfs_for_each_slot(root, &key, &key, path, ret) { 3404df27c4dSYan, Zheng if (key.objectid != dirid || key.type != BTRFS_DIR_INDEX_KEY) 3414df27c4dSYan, Zheng break; 3424df27c4dSYan, Zheng 3432ff7e61eSJeff Mahoney di = btrfs_match_dir_item_name(root->fs_info, path, 344e43eec81SSweet Tea Dorminy name->name, name->len); 3454df27c4dSYan, Zheng if (di) 3464df27c4dSYan, Zheng return di; 3474df27c4dSYan, Zheng } 3489dcbe16fSGabriel Niebler /* Adjust return code if the key was not found in the next leaf. */ 3499dcbe16fSGabriel Niebler if (ret > 0) 3509dcbe16fSGabriel Niebler ret = 0; 3519dcbe16fSGabriel Niebler 3529dcbe16fSGabriel Niebler return ERR_PTR(ret); 3534df27c4dSYan, Zheng } 3544df27c4dSYan, Zheng 3555103e947SJosef Bacik struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans, 3565103e947SJosef Bacik struct btrfs_root *root, 3575103e947SJosef Bacik struct btrfs_path *path, u64 dir, 3585103e947SJosef Bacik const char *name, u16 name_len, 3595103e947SJosef Bacik int mod) 3605103e947SJosef Bacik { 3615103e947SJosef Bacik struct btrfs_key key; 362a7d1c5dcSMarcos Paulo de Souza struct btrfs_dir_item *di; 3635103e947SJosef Bacik 3645103e947SJosef Bacik key.objectid = dir; 365962a298fSDavid Sterba key.type = BTRFS_XATTR_ITEM_KEY; 366df68b8a7SDavid Miller key.offset = btrfs_name_hash(name, name_len); 367a7d1c5dcSMarcos Paulo de Souza 368a7d1c5dcSMarcos Paulo de Souza di = btrfs_lookup_match_dir(trans, root, path, &key, name, name_len, mod); 369a7d1c5dcSMarcos Paulo de Souza if (IS_ERR(di) && PTR_ERR(di) == -ENOENT) 3705103e947SJosef Bacik return NULL; 3715103e947SJosef Bacik 372a7d1c5dcSMarcos Paulo de Souza return di; 3735103e947SJosef Bacik } 3745103e947SJosef Bacik 375d352ac68SChris Mason /* 376d352ac68SChris Mason * helper function to look at the directory item pointed to by 'path' 377d352ac68SChris Mason * this walks through all the entries in a dir item and finds one 378d352ac68SChris Mason * for a specific name. 379d352ac68SChris Mason */ 3802ff7e61eSJeff Mahoney struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_fs_info *fs_info, 3817f5c1516SChris Mason struct btrfs_path *path, 3827f5c1516SChris Mason const char *name, int name_len) 38362e2749eSChris Mason { 38462e2749eSChris Mason struct btrfs_dir_item *dir_item; 3855f39d397SChris Mason unsigned long name_ptr; 3867e38180eSChris Mason u32 total_len; 3877e38180eSChris Mason u32 cur = 0; 3887e38180eSChris Mason u32 this_len; 3895f39d397SChris Mason struct extent_buffer *leaf; 390a8a2ee0cSChris Mason 3915f39d397SChris Mason leaf = path->nodes[0]; 3927e38180eSChris Mason dir_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item); 39322a94d44SJosef Bacik 3943212fa14SJosef Bacik total_len = btrfs_item_size(leaf, path->slots[0]); 3957e38180eSChris Mason while (cur < total_len) { 3965f39d397SChris Mason this_len = sizeof(*dir_item) + 3975103e947SJosef Bacik btrfs_dir_name_len(leaf, dir_item) + 3985103e947SJosef Bacik btrfs_dir_data_len(leaf, dir_item); 3995f39d397SChris Mason name_ptr = (unsigned long)(dir_item + 1); 4007e38180eSChris Mason 4015f39d397SChris Mason if (btrfs_dir_name_len(leaf, dir_item) == name_len && 4025f39d397SChris Mason memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0) 4037e38180eSChris Mason return dir_item; 4047e38180eSChris Mason 4057e38180eSChris Mason cur += this_len; 4067e38180eSChris Mason dir_item = (struct btrfs_dir_item *)((char *)dir_item + 4077e38180eSChris Mason this_len); 40862e2749eSChris Mason } 4097e38180eSChris Mason return NULL; 4107e38180eSChris Mason } 4117e38180eSChris Mason 412d352ac68SChris Mason /* 413d352ac68SChris Mason * given a pointer into a directory item, delete it. This 414d352ac68SChris Mason * handles items that have more than one entry in them. 415d352ac68SChris Mason */ 4167e38180eSChris Mason int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans, 4177e38180eSChris Mason struct btrfs_root *root, 4187e38180eSChris Mason struct btrfs_path *path, 4197e38180eSChris Mason struct btrfs_dir_item *di) 4207e38180eSChris Mason { 4217e38180eSChris Mason 4225f39d397SChris Mason struct extent_buffer *leaf; 4237e38180eSChris Mason u32 sub_item_len; 4247e38180eSChris Mason u32 item_len; 42554aa1f4dSChris Mason int ret = 0; 4267e38180eSChris Mason 4275f39d397SChris Mason leaf = path->nodes[0]; 4285103e947SJosef Bacik sub_item_len = sizeof(*di) + btrfs_dir_name_len(leaf, di) + 4295103e947SJosef Bacik btrfs_dir_data_len(leaf, di); 4303212fa14SJosef Bacik item_len = btrfs_item_size(leaf, path->slots[0]); 4315f39d397SChris Mason if (sub_item_len == item_len) { 4327e38180eSChris Mason ret = btrfs_del_item(trans, root, path); 4337e38180eSChris Mason } else { 4345f39d397SChris Mason /* MARKER */ 4355f39d397SChris Mason unsigned long ptr = (unsigned long)di; 4365f39d397SChris Mason unsigned long start; 4375f39d397SChris Mason 4385f39d397SChris Mason start = btrfs_item_ptr_offset(leaf, path->slots[0]); 4395f39d397SChris Mason memmove_extent_buffer(leaf, ptr, ptr + sub_item_len, 4407e38180eSChris Mason item_len - (ptr + sub_item_len - start)); 44178ac4f9eSDavid Sterba btrfs_truncate_item(path, item_len - sub_item_len, 1); 4427e38180eSChris Mason } 443411fc6bcSAndi Kleen return ret; 4447e38180eSChris Mason } 445