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1/* SPDX-License-Identifier: GPL-2.0-only */2/*3 * This file is part of UBIFS.4 *5 * Copyright (C) 2006-2008 Nokia Corporation6 *7 * Authors: Artem Bityutskiy (Битюцкий Артём)8 * Adrian Hunter9 */10 11/*12 * This file contains miscellaneous helper functions.13 */14 15#ifndef __UBIFS_MISC_H__16#define __UBIFS_MISC_H__17 18/**19 * ubifs_zn_dirty - check if znode is dirty.20 * @znode: znode to check21 *22 * This helper function returns %1 if @znode is dirty and %0 otherwise.23 */24static inline int ubifs_zn_dirty(const struct ubifs_znode *znode)25{26 return !!test_bit(DIRTY_ZNODE, &znode->flags);27}28 29/**30 * ubifs_zn_obsolete - check if znode is obsolete.31 * @znode: znode to check32 *33 * This helper function returns %1 if @znode is obsolete and %0 otherwise.34 */35static inline int ubifs_zn_obsolete(const struct ubifs_znode *znode)36{37 return !!test_bit(OBSOLETE_ZNODE, &znode->flags);38}39 40/**41 * ubifs_zn_cow - check if znode has to be copied on write.42 * @znode: znode to check43 *44 * This helper function returns %1 if @znode is has COW flag set and %045 * otherwise.46 */47static inline int ubifs_zn_cow(const struct ubifs_znode *znode)48{49 return !!test_bit(COW_ZNODE, &znode->flags);50}51 52/**53 * ubifs_wake_up_bgt - wake up background thread.54 * @c: UBIFS file-system description object55 */56static inline void ubifs_wake_up_bgt(struct ubifs_info *c)57{58 if (c->bgt && !c->need_bgt) {59 c->need_bgt = 1;60 wake_up_process(c->bgt);61 }62}63 64/**65 * ubifs_tnc_find_child - find next child in znode.66 * @znode: znode to search at67 * @start: the zbranch index to start at68 *69 * This helper function looks for znode child starting at index @start. Returns70 * the child or %NULL if no children were found.71 */72static inline struct ubifs_znode *73ubifs_tnc_find_child(struct ubifs_znode *znode, int start)74{75 while (start < znode->child_cnt) {76 if (znode->zbranch[start].znode)77 return znode->zbranch[start].znode;78 start += 1;79 }80 81 return NULL;82}83 84/**85 * ubifs_inode - get UBIFS inode information by VFS 'struct inode' object.86 * @inode: the VFS 'struct inode' pointer87 */88static inline struct ubifs_inode *ubifs_inode(const struct inode *inode)89{90 return container_of(inode, struct ubifs_inode, vfs_inode);91}92 93/**94 * ubifs_compr_present - check if compressor was compiled in.95 * @compr_type: compressor type to check96 * @c: the UBIFS file-system description object97 *98 * This function returns %1 of compressor of type @compr_type is present, and99 * %0 if not.100 */101static inline int ubifs_compr_present(struct ubifs_info *c, int compr_type)102{103 ubifs_assert(c, compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT);104 return !!ubifs_compressors[compr_type]->capi_name;105}106 107/**108 * ubifs_compr_name - get compressor name string by its type.109 * @compr_type: compressor type110 * @c: the UBIFS file-system description object111 *112 * This function returns compressor type string.113 */114static inline const char *ubifs_compr_name(struct ubifs_info *c, int compr_type)115{116 ubifs_assert(c, compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT);117 return ubifs_compressors[compr_type]->name;118}119 120/**121 * ubifs_wbuf_sync - synchronize write-buffer.122 * @wbuf: write-buffer to synchronize123 *124 * This is the same as 'ubifs_wbuf_sync_nolock()' but it does not assume125 * that the write-buffer is already locked.126 */127static inline int ubifs_wbuf_sync(struct ubifs_wbuf *wbuf)128{129 int err;130 131 mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);132 err = ubifs_wbuf_sync_nolock(wbuf);133 mutex_unlock(&wbuf->io_mutex);134 return err;135}136 137/**138 * ubifs_encode_dev - encode device node IDs.139 * @dev: UBIFS device node information140 * @rdev: device IDs to encode141 *142 * This is a helper function which encodes major/minor numbers of a device node143 * into UBIFS device node description. We use standard Linux "new" and "huge"144 * encodings.145 */146static inline int ubifs_encode_dev(union ubifs_dev_desc *dev, dev_t rdev)147{148 dev->new = cpu_to_le32(new_encode_dev(rdev));149 return sizeof(dev->new);150}151 152/**153 * ubifs_add_dirt - add dirty space to LEB properties.154 * @c: the UBIFS file-system description object155 * @lnum: LEB to add dirty space for156 * @dirty: dirty space to add157 *158 * This is a helper function which increased amount of dirty LEB space. Returns159 * zero in case of success and a negative error code in case of failure.160 */161static inline int ubifs_add_dirt(struct ubifs_info *c, int lnum, int dirty)162{163 return ubifs_update_one_lp(c, lnum, LPROPS_NC, dirty, 0, 0);164}165 166/**167 * ubifs_return_leb - return LEB to lprops.168 * @c: the UBIFS file-system description object169 * @lnum: LEB to return170 *171 * This helper function cleans the "taken" flag of a logical eraseblock in the172 * lprops. Returns zero in case of success and a negative error code in case of173 * failure.174 */175static inline int ubifs_return_leb(struct ubifs_info *c, int lnum)176{177 return ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,178 LPROPS_TAKEN, 0);179}180 181/**182 * ubifs_idx_node_sz - return index node size.183 * @c: the UBIFS file-system description object184 * @child_cnt: number of children of this index node185 */186static inline int ubifs_idx_node_sz(const struct ubifs_info *c, int child_cnt)187{188 return UBIFS_IDX_NODE_SZ + (UBIFS_BRANCH_SZ + c->key_len + c->hash_len)189 * child_cnt;190}191 192/**193 * ubifs_idx_branch - return pointer to an index branch.194 * @c: the UBIFS file-system description object195 * @idx: index node196 * @bnum: branch number197 */198static inline199struct ubifs_branch *ubifs_idx_branch(const struct ubifs_info *c,200 const struct ubifs_idx_node *idx,201 int bnum)202{203 return (struct ubifs_branch *)((void *)idx->branches +204 (UBIFS_BRANCH_SZ + c->key_len + c->hash_len) * bnum);205}206 207/**208 * ubifs_idx_key - return pointer to an index key.209 * @c: the UBIFS file-system description object210 * @idx: index node211 */212static inline void *ubifs_idx_key(const struct ubifs_info *c,213 const struct ubifs_idx_node *idx)214{215 return (void *)((struct ubifs_branch *)idx->branches)->key;216}217 218/**219 * ubifs_tnc_lookup - look up a file-system node.220 * @c: UBIFS file-system description object221 * @key: node key to lookup222 * @node: the node is returned here223 *224 * This function look up and reads node with key @key. The caller has to make225 * sure the @node buffer is large enough to fit the node. Returns zero in case226 * of success, %-ENOENT if the node was not found, and a negative error code in227 * case of failure.228 */229static inline int ubifs_tnc_lookup(struct ubifs_info *c,230 const union ubifs_key *key, void *node)231{232 return ubifs_tnc_locate(c, key, node, NULL, NULL);233}234 235/**236 * ubifs_get_lprops - get reference to LEB properties.237 * @c: the UBIFS file-system description object238 *239 * This function locks lprops. Lprops have to be unlocked by240 * 'ubifs_release_lprops()'.241 */242static inline void ubifs_get_lprops(struct ubifs_info *c)243{244 mutex_lock(&c->lp_mutex);245}246 247/**248 * ubifs_release_lprops - release lprops lock.249 * @c: the UBIFS file-system description object250 *251 * This function has to be called after each 'ubifs_get_lprops()' call to252 * unlock lprops.253 */254static inline void ubifs_release_lprops(struct ubifs_info *c)255{256 ubifs_assert(c, mutex_is_locked(&c->lp_mutex));257 ubifs_assert(c, c->lst.empty_lebs >= 0 &&258 c->lst.empty_lebs <= c->main_lebs);259 mutex_unlock(&c->lp_mutex);260}261 262/**263 * ubifs_next_log_lnum - switch to the next log LEB.264 * @c: UBIFS file-system description object265 * @lnum: current log LEB266 *267 * This helper function returns the log LEB number which goes next after LEB268 * 'lnum'.269 */270static inline int ubifs_next_log_lnum(const struct ubifs_info *c, int lnum)271{272 lnum += 1;273 if (lnum > c->log_last)274 lnum = UBIFS_LOG_LNUM;275 276 return lnum;277}278 279static inline int ubifs_xattr_max_cnt(struct ubifs_info *c)280{281 int max_xattrs = (c->leb_size / 2) / UBIFS_INO_NODE_SZ;282 283 ubifs_assert(c, max_xattrs < c->max_orphans);284 return max_xattrs;285}286 287const char *ubifs_assert_action_name(struct ubifs_info *c);288 289#endif /* __UBIFS_MISC_H__ */290