1 /* SPDX-License-Identifier: GPL-2.0+ */
3 * This file is part of UBIFS.
5 * Copyright (C) 2006-2008 Nokia Corporation
7 * Authors: Artem Bityutskiy (Битюцкий Артём)
12 * This file contains miscellaneous helper functions.
15 #ifndef __UBIFS_MISC_H__
16 #define __UBIFS_MISC_H__
19 * ubifs_zn_dirty - check if znode is dirty.
20 * @znode: znode to check
22 * This helper function returns %1 if @znode is dirty and %0 otherwise.
24 static inline int ubifs_zn_dirty(const struct ubifs_znode *znode)
26 return !!test_bit(DIRTY_ZNODE, &znode->flags);
30 * ubifs_zn_obsolete - check if znode is obsolete.
31 * @znode: znode to check
33 * This helper function returns %1 if @znode is obsolete and %0 otherwise.
35 static inline int ubifs_zn_obsolete(const struct ubifs_znode *znode)
37 return !!test_bit(OBSOLETE_ZNODE, &znode->flags);
41 * ubifs_zn_cow - check if znode has to be copied on write.
42 * @znode: znode to check
44 * This helper function returns %1 if @znode is has COW flag set and %0
47 static inline int ubifs_zn_cow(const struct ubifs_znode *znode)
49 return !!test_bit(COW_ZNODE, &znode->flags);
53 * ubifs_wake_up_bgt - wake up background thread.
54 * @c: UBIFS file-system description object
56 static inline void ubifs_wake_up_bgt(struct ubifs_info *c)
58 if (c->bgt && !c->need_bgt) {
60 wake_up_process(c->bgt);
65 * ubifs_tnc_find_child - find next child in znode.
66 * @znode: znode to search at
67 * @start: the zbranch index to start at
69 * This helper function looks for znode child starting at index @start. Returns
70 * the child or %NULL if no children were found.
72 static inline struct ubifs_znode *
73 ubifs_tnc_find_child(struct ubifs_znode *znode, int start)
75 while (start < znode->child_cnt) {
76 if (znode->zbranch[start].znode)
77 return znode->zbranch[start].znode;
85 * ubifs_inode - get UBIFS inode information by VFS 'struct inode' object.
86 * @inode: the VFS 'struct inode' pointer
88 static inline struct ubifs_inode *ubifs_inode(const struct inode *inode)
90 return container_of(inode, struct ubifs_inode, vfs_inode);
94 * ubifs_compr_present - check if compressor was compiled in.
95 * @compr_type: compressor type to check
97 * This function returns %1 of compressor of type @compr_type is present, and
100 static inline int ubifs_compr_present(int compr_type)
102 ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT);
103 return !!ubifs_compressors[compr_type]->capi_name;
107 * ubifs_compr_name - get compressor name string by its type.
108 * @compr_type: compressor type
110 * This function returns compressor type string.
112 static inline const char *ubifs_compr_name(int compr_type)
114 ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT);
115 return ubifs_compressors[compr_type]->name;
119 * ubifs_wbuf_sync - synchronize write-buffer.
120 * @wbuf: write-buffer to synchronize
122 * This is the same as as 'ubifs_wbuf_sync_nolock()' but it does not assume
123 * that the write-buffer is already locked.
125 static inline int ubifs_wbuf_sync(struct ubifs_wbuf *wbuf)
129 mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
130 err = ubifs_wbuf_sync_nolock(wbuf);
131 mutex_unlock(&wbuf->io_mutex);
137 * ubifs_encode_dev - encode device node IDs.
138 * @dev: UBIFS device node information
139 * @rdev: device IDs to encode
141 * This is a helper function which encodes major/minor numbers of a device node
142 * into UBIFS device node description. We use standard Linux "new" and "huge"
145 static inline int ubifs_encode_dev(union ubifs_dev_desc *dev, dev_t rdev)
147 if (new_valid_dev(rdev)) {
148 dev->new = cpu_to_le32(new_encode_dev(rdev));
149 return sizeof(dev->new);
151 dev->huge = cpu_to_le64(huge_encode_dev(rdev));
152 return sizeof(dev->huge);
158 * ubifs_add_dirt - add dirty space to LEB properties.
159 * @c: the UBIFS file-system description object
160 * @lnum: LEB to add dirty space for
161 * @dirty: dirty space to add
163 * This is a helper function which increased amount of dirty LEB space. Returns
164 * zero in case of success and a negative error code in case of failure.
166 static inline int ubifs_add_dirt(struct ubifs_info *c, int lnum, int dirty)
168 return ubifs_update_one_lp(c, lnum, LPROPS_NC, dirty, 0, 0);
172 * ubifs_return_leb - return LEB to lprops.
173 * @c: the UBIFS file-system description object
174 * @lnum: LEB to return
176 * This helper function cleans the "taken" flag of a logical eraseblock in the
177 * lprops. Returns zero in case of success and a negative error code in case of
180 static inline int ubifs_return_leb(struct ubifs_info *c, int lnum)
182 return ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
187 * ubifs_idx_node_sz - return index node size.
188 * @c: the UBIFS file-system description object
189 * @child_cnt: number of children of this index node
191 static inline int ubifs_idx_node_sz(const struct ubifs_info *c, int child_cnt)
193 return UBIFS_IDX_NODE_SZ + (UBIFS_BRANCH_SZ + c->key_len) * child_cnt;
197 * ubifs_idx_branch - return pointer to an index branch.
198 * @c: the UBIFS file-system description object
200 * @bnum: branch number
203 struct ubifs_branch *ubifs_idx_branch(const struct ubifs_info *c,
204 const struct ubifs_idx_node *idx,
207 return (struct ubifs_branch *)((void *)idx->branches +
208 (UBIFS_BRANCH_SZ + c->key_len) * bnum);
212 * ubifs_idx_key - return pointer to an index key.
213 * @c: the UBIFS file-system description object
216 static inline void *ubifs_idx_key(const struct ubifs_info *c,
217 const struct ubifs_idx_node *idx)
220 return (void *)((struct ubifs_branch *)idx->branches)->key;
222 struct ubifs_branch *tmp;
224 tmp = (struct ubifs_branch *)idx->branches;
225 return (void *)tmp->key;
230 * ubifs_current_time - round current time to time granularity.
233 static inline struct timespec ubifs_current_time(struct inode *inode)
235 return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
236 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
240 * ubifs_tnc_lookup - look up a file-system node.
241 * @c: UBIFS file-system description object
242 * @key: node key to lookup
243 * @node: the node is returned here
245 * This function look up and reads node with key @key. The caller has to make
246 * sure the @node buffer is large enough to fit the node. Returns zero in case
247 * of success, %-ENOENT if the node was not found, and a negative error code in
250 static inline int ubifs_tnc_lookup(struct ubifs_info *c,
251 const union ubifs_key *key, void *node)
253 return ubifs_tnc_locate(c, key, node, NULL, NULL);
257 * ubifs_get_lprops - get reference to LEB properties.
258 * @c: the UBIFS file-system description object
260 * This function locks lprops. Lprops have to be unlocked by
261 * 'ubifs_release_lprops()'.
263 static inline void ubifs_get_lprops(struct ubifs_info *c)
265 mutex_lock(&c->lp_mutex);
269 * ubifs_release_lprops - release lprops lock.
270 * @c: the UBIFS file-system description object
272 * This function has to be called after each 'ubifs_get_lprops()' call to
275 static inline void ubifs_release_lprops(struct ubifs_info *c)
277 ubifs_assert(mutex_is_locked(&c->lp_mutex));
278 ubifs_assert(c->lst.empty_lebs >= 0 &&
279 c->lst.empty_lebs <= c->main_lebs);
280 mutex_unlock(&c->lp_mutex);
284 * ubifs_next_log_lnum - switch to the next log LEB.
285 * @c: UBIFS file-system description object
286 * @lnum: current log LEB
288 * This helper function returns the log LEB number which goes next after LEB
291 static inline int ubifs_next_log_lnum(const struct ubifs_info *c, int lnum)
294 if (lnum > c->log_last)
295 lnum = UBIFS_LOG_LNUM;
300 #endif /* __UBIFS_MISC_H__ */