2 * This file is part of UBIFS.
4 * Copyright (C) 2006-2008 Nokia Corporation
6 * SPDX-License-Identifier: GPL-2.0+
8 * Authors: Artem Bityutskiy (Битюцкий Артём)
13 * This file contains miscellaneous helper functions.
16 #ifndef __UBIFS_MISC_H__
17 #define __UBIFS_MISC_H__
21 * ubifs_zn_dirty - check if znode is dirty.
22 * @znode: znode to check
24 * This helper function returns %1 if @znode is dirty and %0 otherwise.
26 static inline int ubifs_zn_dirty(const struct ubifs_znode *znode)
28 return !!test_bit(DIRTY_ZNODE, &znode->flags);
32 * ubifs_zn_obsolete - check if znode is obsolete.
33 * @znode: znode to check
35 * This helper function returns %1 if @znode is obsolete and %0 otherwise.
37 static inline int ubifs_zn_obsolete(const struct ubifs_znode *znode)
39 return !!test_bit(OBSOLETE_ZNODE, &znode->flags);
43 * ubifs_zn_cow - check if znode has to be copied on write.
44 * @znode: znode to check
46 * This helper function returns %1 if @znode is has COW flag set and %0
49 static inline int ubifs_zn_cow(const struct ubifs_znode *znode)
51 return !!test_bit(COW_ZNODE, &znode->flags);
55 * ubifs_wake_up_bgt - wake up background thread.
56 * @c: UBIFS file-system description object
58 static inline void ubifs_wake_up_bgt(struct ubifs_info *c)
60 if (c->bgt && !c->need_bgt) {
62 wake_up_process(c->bgt);
67 * ubifs_tnc_find_child - find next child in znode.
68 * @znode: znode to search at
69 * @start: the zbranch index to start at
71 * This helper function looks for znode child starting at index @start. Returns
72 * the child or %NULL if no children were found.
74 static inline struct ubifs_znode *
75 ubifs_tnc_find_child(struct ubifs_znode *znode, int start)
77 while (start < znode->child_cnt) {
78 if (znode->zbranch[start].znode)
79 return znode->zbranch[start].znode;
87 * ubifs_inode - get UBIFS inode information by VFS 'struct inode' object.
88 * @inode: the VFS 'struct inode' pointer
90 static inline struct ubifs_inode *ubifs_inode(const struct inode *inode)
92 return container_of(inode, struct ubifs_inode, vfs_inode);
96 * ubifs_compr_present - check if compressor was compiled in.
97 * @compr_type: compressor type to check
99 * This function returns %1 of compressor of type @compr_type is present, and
102 static inline int ubifs_compr_present(int compr_type)
104 ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT);
105 return !!ubifs_compressors[compr_type]->capi_name;
109 * ubifs_compr_name - get compressor name string by its type.
110 * @compr_type: compressor type
112 * This function returns compressor type string.
114 static inline const char *ubifs_compr_name(int compr_type)
116 ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT);
117 return ubifs_compressors[compr_type]->name;
121 * ubifs_wbuf_sync - synchronize write-buffer.
122 * @wbuf: write-buffer to synchronize
124 * This is the same as as 'ubifs_wbuf_sync_nolock()' but it does not assume
125 * that the write-buffer is already locked.
127 static inline int ubifs_wbuf_sync(struct ubifs_wbuf *wbuf)
131 mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
132 err = ubifs_wbuf_sync_nolock(wbuf);
133 mutex_unlock(&wbuf->io_mutex);
139 * ubifs_encode_dev - encode device node IDs.
140 * @dev: UBIFS device node information
141 * @rdev: device IDs to encode
143 * This is a helper function which encodes major/minor numbers of a device node
144 * into UBIFS device node description. We use standard Linux "new" and "huge"
147 static inline int ubifs_encode_dev(union ubifs_dev_desc *dev, dev_t rdev)
149 if (new_valid_dev(rdev)) {
150 dev->new = cpu_to_le32(new_encode_dev(rdev));
151 return sizeof(dev->new);
153 dev->huge = cpu_to_le64(huge_encode_dev(rdev));
154 return sizeof(dev->huge);
160 * ubifs_add_dirt - add dirty space to LEB properties.
161 * @c: the UBIFS file-system description object
162 * @lnum: LEB to add dirty space for
163 * @dirty: dirty space to add
165 * This is a helper function which increased amount of dirty LEB space. Returns
166 * zero in case of success and a negative error code in case of failure.
168 static inline int ubifs_add_dirt(struct ubifs_info *c, int lnum, int dirty)
170 return ubifs_update_one_lp(c, lnum, LPROPS_NC, dirty, 0, 0);
174 * ubifs_return_leb - return LEB to lprops.
175 * @c: the UBIFS file-system description object
176 * @lnum: LEB to return
178 * This helper function cleans the "taken" flag of a logical eraseblock in the
179 * lprops. Returns zero in case of success and a negative error code in case of
182 static inline int ubifs_return_leb(struct ubifs_info *c, int lnum)
184 return ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
189 * ubifs_idx_node_sz - return index node size.
190 * @c: the UBIFS file-system description object
191 * @child_cnt: number of children of this index node
193 static inline int ubifs_idx_node_sz(const struct ubifs_info *c, int child_cnt)
195 return UBIFS_IDX_NODE_SZ + (UBIFS_BRANCH_SZ + c->key_len) * child_cnt;
199 * ubifs_idx_branch - return pointer to an index branch.
200 * @c: the UBIFS file-system description object
202 * @bnum: branch number
205 struct ubifs_branch *ubifs_idx_branch(const struct ubifs_info *c,
206 const struct ubifs_idx_node *idx,
209 return (struct ubifs_branch *)((void *)idx->branches +
210 (UBIFS_BRANCH_SZ + c->key_len) * bnum);
214 * ubifs_idx_key - return pointer to an index key.
215 * @c: the UBIFS file-system description object
218 static inline void *ubifs_idx_key(const struct ubifs_info *c,
219 const struct ubifs_idx_node *idx)
222 return (void *)((struct ubifs_branch *)idx->branches)->key;
224 struct ubifs_branch *tmp;
226 tmp = (struct ubifs_branch *)idx->branches;
227 return (void *)tmp->key;
232 * ubifs_current_time - round current time to time granularity.
235 static inline struct timespec ubifs_current_time(struct inode *inode)
237 return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ?
238 current_fs_time(inode->i_sb) : CURRENT_TIME_SEC;
242 * ubifs_tnc_lookup - look up a file-system node.
243 * @c: UBIFS file-system description object
244 * @key: node key to lookup
245 * @node: the node is returned here
247 * This function look up and reads node with key @key. The caller has to make
248 * sure the @node buffer is large enough to fit the node. Returns zero in case
249 * of success, %-ENOENT if the node was not found, and a negative error code in
252 static inline int ubifs_tnc_lookup(struct ubifs_info *c,
253 const union ubifs_key *key, void *node)
255 return ubifs_tnc_locate(c, key, node, NULL, NULL);
259 * ubifs_get_lprops - get reference to LEB properties.
260 * @c: the UBIFS file-system description object
262 * This function locks lprops. Lprops have to be unlocked by
263 * 'ubifs_release_lprops()'.
265 static inline void ubifs_get_lprops(struct ubifs_info *c)
267 mutex_lock(&c->lp_mutex);
271 * ubifs_release_lprops - release lprops lock.
272 * @c: the UBIFS file-system description object
274 * This function has to be called after each 'ubifs_get_lprops()' call to
277 static inline void ubifs_release_lprops(struct ubifs_info *c)
279 ubifs_assert(mutex_is_locked(&c->lp_mutex));
280 ubifs_assert(c->lst.empty_lebs >= 0 &&
281 c->lst.empty_lebs <= c->main_lebs);
282 mutex_unlock(&c->lp_mutex);
286 * ubifs_next_log_lnum - switch to the next log LEB.
287 * @c: UBIFS file-system description object
288 * @lnum: current log LEB
290 * This helper function returns the log LEB number which goes next after LEB
293 static inline int ubifs_next_log_lnum(const struct ubifs_info *c, int lnum)
296 if (lnum > c->log_last)
297 lnum = UBIFS_LOG_LNUM;
302 #endif /* __UBIFS_MISC_H__ */