1c1d7c514SDavid Sterba // SPDX-License-Identifier: GPL-2.0 26cbd5570SChris Mason /* 36cbd5570SChris Mason * Copyright (C) 2007 Oracle. All rights reserved. 46cbd5570SChris Mason */ 56cbd5570SChris Mason 662e2749eSChris Mason #include "ctree.h" 762e2749eSChris Mason #include "disk-io.h" 8e089f05cSChris Mason #include "transaction.h" 962e2749eSChris Mason 10d352ac68SChris Mason /* 11d352ac68SChris Mason * insert a name into a directory, doing overflow properly if there is a hash 12d352ac68SChris Mason * collision. data_size indicates how big the item inserted should be. On 13d352ac68SChris Mason * success a struct btrfs_dir_item pointer is returned, otherwise it is 14d352ac68SChris Mason * an ERR_PTR. 15d352ac68SChris Mason * 16d352ac68SChris Mason * The name is not copied into the dir item, you have to do that yourself. 17d352ac68SChris Mason */ 1835b7e476SChris Mason static struct btrfs_dir_item *insert_with_overflow(struct btrfs_trans_handle 1935b7e476SChris Mason *trans, 207e38180eSChris Mason struct btrfs_root *root, 217e38180eSChris Mason struct btrfs_path *path, 227e38180eSChris Mason struct btrfs_key *cpu_key, 23e06afa83SChris Mason u32 data_size, 24e06afa83SChris Mason const char *name, 25e06afa83SChris Mason int name_len) 267fcde0e3SChris Mason { 272ff7e61eSJeff Mahoney struct btrfs_fs_info *fs_info = root->fs_info; 287fcde0e3SChris Mason int ret; 297e38180eSChris Mason char *ptr; 307e38180eSChris Mason struct btrfs_item *item; 315f39d397SChris Mason struct extent_buffer *leaf; 327fcde0e3SChris Mason 337fcde0e3SChris Mason ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size); 347e38180eSChris Mason if (ret == -EEXIST) { 35e06afa83SChris Mason struct btrfs_dir_item *di; 362ff7e61eSJeff Mahoney di = btrfs_match_dir_item_name(fs_info, path, name, name_len); 37e06afa83SChris Mason if (di) 38e06afa83SChris Mason return ERR_PTR(-EEXIST); 39c71dd880SDavid Sterba btrfs_extend_item(path, data_size); 40143bede5SJeff Mahoney } else if (ret < 0) 4154aa1f4dSChris Mason return ERR_PTR(ret); 427e38180eSChris Mason WARN_ON(ret > 0); 435f39d397SChris Mason leaf = path->nodes[0]; 44dd3cc16bSRoss Kirk item = btrfs_item_nr(path->slots[0]); 457e38180eSChris Mason ptr = btrfs_item_ptr(leaf, path->slots[0], char); 465f39d397SChris Mason BUG_ON(data_size > btrfs_item_size(leaf, item)); 475f39d397SChris Mason ptr += btrfs_item_size(leaf, item) - 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); 865103e947SJosef Bacik btrfs_set_dir_type(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 */ 108684572dfSLu Fengqi int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, const char *name, 109684572dfSLu Fengqi int name_len, 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; 125df68b8a7SDavid Miller key.offset = btrfs_name_hash(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 13362e2749eSChris Mason data_size = sizeof(*dir_item) + name_len; 134e06afa83SChris Mason dir_item = insert_with_overflow(trans, root, path, &key, data_size, 135e06afa83SChris Mason 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 1435f39d397SChris Mason leaf = path->nodes[0]; 1445f39d397SChris Mason btrfs_set_dir_item_key(leaf, dir_item, &disk_key); 1455f39d397SChris Mason btrfs_set_dir_type(leaf, dir_item, type); 1465103e947SJosef Bacik btrfs_set_dir_data_len(leaf, dir_item, 0); 1475f39d397SChris Mason btrfs_set_dir_name_len(leaf, dir_item, name_len); 148e02119d5SChris Mason btrfs_set_dir_transid(leaf, dir_item, trans->transid); 1495f39d397SChris Mason name_ptr = (unsigned long)(dir_item + 1); 150c5739bbaSChris Mason 1515f39d397SChris Mason write_extent_buffer(leaf, name, name_ptr, name_len); 1525f39d397SChris Mason btrfs_mark_buffer_dirty(leaf); 1537e38180eSChris Mason 154e06afa83SChris Mason second_insert: 1557e38180eSChris Mason /* FIXME, use some real flag for selecting the extra index */ 1567e38180eSChris Mason if (root == root->fs_info->tree_root) { 1577e38180eSChris Mason ret = 0; 158c2db1073STsutomu Itoh goto out_free; 1597e38180eSChris Mason } 160b3b4aa74SDavid Sterba btrfs_release_path(path); 1617e38180eSChris Mason 1624465c8b4SLu Fengqi ret2 = btrfs_insert_delayed_dir_index(trans, name, name_len, dir, 1634465c8b4SLu Fengqi &disk_key, type, index); 164c2db1073STsutomu Itoh out_free: 1655caf2a00SChris Mason btrfs_free_path(path); 166e06afa83SChris Mason if (ret) 16762e2749eSChris Mason return ret; 168e06afa83SChris Mason if (ret2) 169e06afa83SChris Mason return ret2; 170e06afa83SChris Mason return 0; 17162e2749eSChris Mason } 17262e2749eSChris Mason 173a7d1c5dcSMarcos Paulo de Souza static struct btrfs_dir_item *btrfs_lookup_match_dir( 174a7d1c5dcSMarcos Paulo de Souza struct btrfs_trans_handle *trans, 175a7d1c5dcSMarcos Paulo de Souza struct btrfs_root *root, struct btrfs_path *path, 176a7d1c5dcSMarcos Paulo de Souza struct btrfs_key *key, const char *name, 177a7d1c5dcSMarcos Paulo de Souza int name_len, int mod) 178a7d1c5dcSMarcos Paulo de Souza { 179a7d1c5dcSMarcos Paulo de Souza const int ins_len = (mod < 0 ? -1 : 0); 180a7d1c5dcSMarcos Paulo de Souza const int cow = (mod != 0); 181a7d1c5dcSMarcos Paulo de Souza int ret; 182a7d1c5dcSMarcos Paulo de Souza 183a7d1c5dcSMarcos Paulo de Souza ret = btrfs_search_slot(trans, root, key, path, ins_len, cow); 184a7d1c5dcSMarcos Paulo de Souza if (ret < 0) 185a7d1c5dcSMarcos Paulo de Souza return ERR_PTR(ret); 186a7d1c5dcSMarcos Paulo de Souza if (ret > 0) 187a7d1c5dcSMarcos Paulo de Souza return ERR_PTR(-ENOENT); 188a7d1c5dcSMarcos Paulo de Souza 189a7d1c5dcSMarcos Paulo de Souza return btrfs_match_dir_item_name(root->fs_info, path, name, name_len); 190a7d1c5dcSMarcos Paulo de Souza } 191a7d1c5dcSMarcos Paulo de Souza 192d352ac68SChris Mason /* 193*8dcbc261SFilipe Manana * Lookup for a directory item by name. 194*8dcbc261SFilipe Manana * 195*8dcbc261SFilipe Manana * @trans: The transaction handle to use. Can be NULL if @mod is 0. 196*8dcbc261SFilipe Manana * @root: The root of the target tree. 197*8dcbc261SFilipe Manana * @path: Path to use for the search. 198*8dcbc261SFilipe Manana * @dir: The inode number (objectid) of the directory. 199*8dcbc261SFilipe Manana * @name: The name associated to the directory entry we are looking for. 200*8dcbc261SFilipe Manana * @name_len: The length of the name. 201*8dcbc261SFilipe Manana * @mod: Used to indicate if the tree search is meant for a read only 202*8dcbc261SFilipe Manana * lookup, for a modification lookup or for a deletion lookup, so 203*8dcbc261SFilipe Manana * its value should be 0, 1 or -1, respectively. 204*8dcbc261SFilipe Manana * 205*8dcbc261SFilipe Manana * Returns: NULL if the dir item does not exists, an error pointer if an error 206*8dcbc261SFilipe Manana * happened, or a pointer to a dir item if a dir item exists for the given name. 207d352ac68SChris Mason */ 2087e38180eSChris Mason struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, 2097e38180eSChris Mason struct btrfs_root *root, 2107e38180eSChris Mason struct btrfs_path *path, u64 dir, 2117e38180eSChris Mason const char *name, int name_len, 2127e38180eSChris Mason int mod) 21362e2749eSChris Mason { 21462e2749eSChris Mason struct btrfs_key key; 215a7d1c5dcSMarcos Paulo de Souza struct btrfs_dir_item *di; 21662e2749eSChris Mason 21762e2749eSChris Mason key.objectid = dir; 218962a298fSDavid Sterba key.type = BTRFS_DIR_ITEM_KEY; 219df68b8a7SDavid Miller key.offset = btrfs_name_hash(name, name_len); 2205f39d397SChris Mason 221a7d1c5dcSMarcos Paulo de Souza di = btrfs_lookup_match_dir(trans, root, path, &key, name, name_len, mod); 222a7d1c5dcSMarcos Paulo de Souza if (IS_ERR(di) && PTR_ERR(di) == -ENOENT) 2237e38180eSChris Mason return NULL; 2247fcde0e3SChris Mason 225a7d1c5dcSMarcos Paulo de Souza return di; 22662e2749eSChris Mason } 22762e2749eSChris Mason 2289c52057cSChris Mason int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir, 2299c52057cSChris Mason const char *name, int name_len) 2309c52057cSChris Mason { 2319c52057cSChris Mason int ret; 2329c52057cSChris Mason struct btrfs_key key; 2339c52057cSChris Mason struct btrfs_dir_item *di; 2349c52057cSChris Mason int data_size; 2359c52057cSChris Mason struct extent_buffer *leaf; 2369c52057cSChris Mason int slot; 2379c52057cSChris Mason struct btrfs_path *path; 2389c52057cSChris Mason 2399c52057cSChris Mason path = btrfs_alloc_path(); 2409c52057cSChris Mason if (!path) 2419c52057cSChris Mason return -ENOMEM; 2429c52057cSChris Mason 2439c52057cSChris Mason key.objectid = dir; 244962a298fSDavid Sterba key.type = BTRFS_DIR_ITEM_KEY; 2459c52057cSChris Mason key.offset = btrfs_name_hash(name, name_len); 2469c52057cSChris Mason 247a7d1c5dcSMarcos Paulo de Souza di = btrfs_lookup_match_dir(NULL, root, path, &key, name, name_len, 0); 248a7d1c5dcSMarcos Paulo de Souza if (IS_ERR(di)) { 249a7d1c5dcSMarcos Paulo de Souza ret = PTR_ERR(di); 250a7d1c5dcSMarcos Paulo de Souza /* Nothing found, we're safe */ 251a7d1c5dcSMarcos Paulo de Souza if (ret == -ENOENT) { 2529c52057cSChris Mason ret = 0; 2539c52057cSChris Mason goto out; 2549c52057cSChris Mason } 2559c52057cSChris Mason 256a7d1c5dcSMarcos Paulo de Souza if (ret < 0) 257a7d1c5dcSMarcos Paulo de Souza goto out; 258a7d1c5dcSMarcos Paulo de Souza } 259a7d1c5dcSMarcos Paulo de Souza 2609c52057cSChris Mason /* we found an item, look for our name in the item */ 2619c52057cSChris Mason if (di) { 2629c52057cSChris Mason /* our exact name was found */ 2639c52057cSChris Mason ret = -EEXIST; 2649c52057cSChris Mason goto out; 2659c52057cSChris Mason } 2669c52057cSChris Mason 2679c52057cSChris Mason /* 2689c52057cSChris Mason * see if there is room in the item to insert this 2699c52057cSChris Mason * name 2709c52057cSChris Mason */ 271878f2d2cSFilipe David Borba Manana data_size = sizeof(*di) + name_len; 2729c52057cSChris Mason leaf = path->nodes[0]; 2739c52057cSChris Mason slot = path->slots[0]; 2749c52057cSChris Mason if (data_size + btrfs_item_size_nr(leaf, slot) + 275da17066cSJeff Mahoney sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(root->fs_info)) { 2769c52057cSChris Mason ret = -EOVERFLOW; 2779c52057cSChris Mason } else { 2789c52057cSChris Mason /* plenty of insertion room */ 2799c52057cSChris Mason ret = 0; 2809c52057cSChris Mason } 2819c52057cSChris Mason out: 2829c52057cSChris Mason btrfs_free_path(path); 2839c52057cSChris Mason return ret; 2849c52057cSChris Mason } 2859c52057cSChris Mason 286d352ac68SChris Mason /* 287*8dcbc261SFilipe Manana * Lookup for a directory index item by name and index number. 288d352ac68SChris Mason * 289*8dcbc261SFilipe Manana * @trans: The transaction handle to use. Can be NULL if @mod is 0. 290*8dcbc261SFilipe Manana * @root: The root of the target tree. 291*8dcbc261SFilipe Manana * @path: Path to use for the search. 292*8dcbc261SFilipe Manana * @dir: The inode number (objectid) of the directory. 293*8dcbc261SFilipe Manana * @index: The index number. 294*8dcbc261SFilipe Manana * @name: The name associated to the directory entry we are looking for. 295*8dcbc261SFilipe Manana * @name_len: The length of the name. 296*8dcbc261SFilipe Manana * @mod: Used to indicate if the tree search is meant for a read only 297*8dcbc261SFilipe Manana * lookup, for a modification lookup or for a deletion lookup, so 298*8dcbc261SFilipe Manana * its value should be 0, 1 or -1, respectively. 299*8dcbc261SFilipe Manana * 300*8dcbc261SFilipe Manana * Returns: NULL if the dir index item does not exists, an error pointer if an 301*8dcbc261SFilipe Manana * error happened, or a pointer to a dir item if the dir index item exists and 302*8dcbc261SFilipe Manana * matches the criteria (name and index number). 303d352ac68SChris Mason */ 3047e38180eSChris Mason struct btrfs_dir_item * 3057e38180eSChris Mason btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans, 3067e38180eSChris Mason struct btrfs_root *root, 3077e38180eSChris Mason struct btrfs_path *path, u64 dir, 308*8dcbc261SFilipe Manana u64 index, const char *name, int name_len, 3097e38180eSChris Mason int mod) 3107e38180eSChris Mason { 311*8dcbc261SFilipe Manana struct btrfs_dir_item *di; 3127e38180eSChris Mason struct btrfs_key key; 3137e38180eSChris Mason 3147e38180eSChris Mason key.objectid = dir; 315962a298fSDavid Sterba key.type = BTRFS_DIR_INDEX_KEY; 316*8dcbc261SFilipe Manana key.offset = index; 3177e38180eSChris Mason 318*8dcbc261SFilipe Manana di = btrfs_lookup_match_dir(trans, root, path, &key, name, name_len, mod); 319*8dcbc261SFilipe Manana if (di == ERR_PTR(-ENOENT)) 320*8dcbc261SFilipe Manana return NULL; 321*8dcbc261SFilipe Manana 322*8dcbc261SFilipe Manana return di; 3237e38180eSChris Mason } 3247e38180eSChris Mason 3254df27c4dSYan, Zheng struct btrfs_dir_item * 3264df27c4dSYan, Zheng btrfs_search_dir_index_item(struct btrfs_root *root, 3274df27c4dSYan, Zheng struct btrfs_path *path, u64 dirid, 3284df27c4dSYan, Zheng const char *name, int name_len) 3294df27c4dSYan, Zheng { 3304df27c4dSYan, Zheng struct extent_buffer *leaf; 3314df27c4dSYan, Zheng struct btrfs_dir_item *di; 3324df27c4dSYan, Zheng struct btrfs_key key; 3334df27c4dSYan, Zheng u32 nritems; 3344df27c4dSYan, Zheng int ret; 3354df27c4dSYan, Zheng 3364df27c4dSYan, Zheng key.objectid = dirid; 3374df27c4dSYan, Zheng key.type = BTRFS_DIR_INDEX_KEY; 3384df27c4dSYan, Zheng key.offset = 0; 3394df27c4dSYan, Zheng 3404df27c4dSYan, Zheng ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3414df27c4dSYan, Zheng if (ret < 0) 3424df27c4dSYan, Zheng return ERR_PTR(ret); 3434df27c4dSYan, Zheng 3444df27c4dSYan, Zheng leaf = path->nodes[0]; 3454df27c4dSYan, Zheng nritems = btrfs_header_nritems(leaf); 3464df27c4dSYan, Zheng 3474df27c4dSYan, Zheng while (1) { 3484df27c4dSYan, Zheng if (path->slots[0] >= nritems) { 3494df27c4dSYan, Zheng ret = btrfs_next_leaf(root, path); 3504df27c4dSYan, Zheng if (ret < 0) 3514df27c4dSYan, Zheng return ERR_PTR(ret); 3524df27c4dSYan, Zheng if (ret > 0) 3534df27c4dSYan, Zheng break; 3544df27c4dSYan, Zheng leaf = path->nodes[0]; 3554df27c4dSYan, Zheng nritems = btrfs_header_nritems(leaf); 3564df27c4dSYan, Zheng continue; 3574df27c4dSYan, Zheng } 3584df27c4dSYan, Zheng 3594df27c4dSYan, Zheng btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 3604df27c4dSYan, Zheng if (key.objectid != dirid || key.type != BTRFS_DIR_INDEX_KEY) 3614df27c4dSYan, Zheng break; 3624df27c4dSYan, Zheng 3632ff7e61eSJeff Mahoney di = btrfs_match_dir_item_name(root->fs_info, path, 3642ff7e61eSJeff Mahoney name, name_len); 3654df27c4dSYan, Zheng if (di) 3664df27c4dSYan, Zheng return di; 3674df27c4dSYan, Zheng 3684df27c4dSYan, Zheng path->slots[0]++; 3694df27c4dSYan, Zheng } 3704df27c4dSYan, Zheng return NULL; 3714df27c4dSYan, Zheng } 3724df27c4dSYan, Zheng 3735103e947SJosef Bacik struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans, 3745103e947SJosef Bacik struct btrfs_root *root, 3755103e947SJosef Bacik struct btrfs_path *path, u64 dir, 3765103e947SJosef Bacik const char *name, u16 name_len, 3775103e947SJosef Bacik int mod) 3785103e947SJosef Bacik { 3795103e947SJosef Bacik struct btrfs_key key; 380a7d1c5dcSMarcos Paulo de Souza struct btrfs_dir_item *di; 3815103e947SJosef Bacik 3825103e947SJosef Bacik key.objectid = dir; 383962a298fSDavid Sterba key.type = BTRFS_XATTR_ITEM_KEY; 384df68b8a7SDavid Miller key.offset = btrfs_name_hash(name, name_len); 385a7d1c5dcSMarcos Paulo de Souza 386a7d1c5dcSMarcos Paulo de Souza di = btrfs_lookup_match_dir(trans, root, path, &key, name, name_len, mod); 387a7d1c5dcSMarcos Paulo de Souza if (IS_ERR(di) && PTR_ERR(di) == -ENOENT) 3885103e947SJosef Bacik return NULL; 3895103e947SJosef Bacik 390a7d1c5dcSMarcos Paulo de Souza return di; 3915103e947SJosef Bacik } 3925103e947SJosef Bacik 393d352ac68SChris Mason /* 394d352ac68SChris Mason * helper function to look at the directory item pointed to by 'path' 395d352ac68SChris Mason * this walks through all the entries in a dir item and finds one 396d352ac68SChris Mason * for a specific name. 397d352ac68SChris Mason */ 3982ff7e61eSJeff Mahoney struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_fs_info *fs_info, 3997f5c1516SChris Mason struct btrfs_path *path, 4007f5c1516SChris Mason const char *name, int name_len) 40162e2749eSChris Mason { 40262e2749eSChris Mason struct btrfs_dir_item *dir_item; 4035f39d397SChris Mason unsigned long name_ptr; 4047e38180eSChris Mason u32 total_len; 4057e38180eSChris Mason u32 cur = 0; 4067e38180eSChris Mason u32 this_len; 4075f39d397SChris Mason struct extent_buffer *leaf; 408a8a2ee0cSChris Mason 4095f39d397SChris Mason leaf = path->nodes[0]; 4107e38180eSChris Mason dir_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item); 41122a94d44SJosef Bacik 4125f39d397SChris Mason total_len = btrfs_item_size_nr(leaf, path->slots[0]); 4137e38180eSChris Mason while (cur < total_len) { 4145f39d397SChris Mason this_len = sizeof(*dir_item) + 4155103e947SJosef Bacik btrfs_dir_name_len(leaf, dir_item) + 4165103e947SJosef Bacik btrfs_dir_data_len(leaf, dir_item); 4175f39d397SChris Mason name_ptr = (unsigned long)(dir_item + 1); 4187e38180eSChris Mason 4195f39d397SChris Mason if (btrfs_dir_name_len(leaf, dir_item) == name_len && 4205f39d397SChris Mason memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0) 4217e38180eSChris Mason return dir_item; 4227e38180eSChris Mason 4237e38180eSChris Mason cur += this_len; 4247e38180eSChris Mason dir_item = (struct btrfs_dir_item *)((char *)dir_item + 4257e38180eSChris Mason this_len); 42662e2749eSChris Mason } 4277e38180eSChris Mason return NULL; 4287e38180eSChris Mason } 4297e38180eSChris Mason 430d352ac68SChris Mason /* 431d352ac68SChris Mason * given a pointer into a directory item, delete it. This 432d352ac68SChris Mason * handles items that have more than one entry in them. 433d352ac68SChris Mason */ 4347e38180eSChris Mason int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans, 4357e38180eSChris Mason struct btrfs_root *root, 4367e38180eSChris Mason struct btrfs_path *path, 4377e38180eSChris Mason struct btrfs_dir_item *di) 4387e38180eSChris Mason { 4397e38180eSChris Mason 4405f39d397SChris Mason struct extent_buffer *leaf; 4417e38180eSChris Mason u32 sub_item_len; 4427e38180eSChris Mason u32 item_len; 44354aa1f4dSChris Mason int ret = 0; 4447e38180eSChris Mason 4455f39d397SChris Mason leaf = path->nodes[0]; 4465103e947SJosef Bacik sub_item_len = sizeof(*di) + btrfs_dir_name_len(leaf, di) + 4475103e947SJosef Bacik btrfs_dir_data_len(leaf, di); 4485f39d397SChris Mason item_len = btrfs_item_size_nr(leaf, path->slots[0]); 4495f39d397SChris Mason if (sub_item_len == item_len) { 4507e38180eSChris Mason ret = btrfs_del_item(trans, root, path); 4517e38180eSChris Mason } else { 4525f39d397SChris Mason /* MARKER */ 4535f39d397SChris Mason unsigned long ptr = (unsigned long)di; 4545f39d397SChris Mason unsigned long start; 4555f39d397SChris Mason 4565f39d397SChris Mason start = btrfs_item_ptr_offset(leaf, path->slots[0]); 4575f39d397SChris Mason memmove_extent_buffer(leaf, ptr, ptr + sub_item_len, 4587e38180eSChris Mason item_len - (ptr + sub_item_len - start)); 45978ac4f9eSDavid Sterba btrfs_truncate_item(path, item_len - sub_item_len, 1); 4607e38180eSChris Mason } 461411fc6bcSAndi Kleen return ret; 4627e38180eSChris Mason } 463