1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
2 | /* |
3 | * This file is part of UBIFS. |
4 | * |
5 | * Copyright (C) 2006-2008 Nokia Corporation |
6 | * |
7 | * Authors: Artem Bityutskiy (Битюцкий Артём) |
8 | * Adrian Hunter |
9 | */ |
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 check |
21 | * |
22 | * This helper function returns %1 if @znode is dirty and %0 otherwise. |
23 | */ |
24 | static 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30 | * ubifs_zn_obsolete - check if znode is obsolete.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 check |
32 | * |
33 | * This helper function returns %1 if @znode is obsolete and %0 otherwise. |
34 | */ |
35 | static 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 check |
43 | * |
44 | * This helper function returns %1 if @znode is has COW flag set and %0 |
45 | * otherwise. |
46 | */ |
47 | static 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 object |
55 | */ |
56 | static 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(tsk: c->bgt); |
61 | } |
62 | } |
63 | |
64 | /** |
65 | * ubifs_tnc_find_child - find next child in znode. |
66 | * @znode: znode to search at |
67 | * @start: the zbranch index to start at |
68 | * |
69 | * This helper function looks for znode child starting at index @start. Returns |
70 | * the child or %NULL if no children were found. |
71 | */ |
72 | static inline struct ubifs_znode * |
73 | ubifs_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' pointer |
87 | */ |
88 | static 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 check |
96 | * @c: the UBIFS file-system description object |
97 | * |
98 | * This function returns %1 of compressor of type @compr_type is present, and |
99 | * %0 if not. |
100 | */ |
101 | static 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 type |
110 | * @c: the UBIFS file-system description object |
111 | * |
112 | * This function returns compressor type string. |
113 | */ |
114 | static 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 synchronize |
123 | * |
124 | * This is the same as 'ubifs_wbuf_sync_nolock()' but it does not assume |
125 | * that the write-buffer is already locked. |
126 | */ |
127 | static inline int ubifs_wbuf_sync(struct ubifs_wbuf *wbuf) |
128 | { |
129 | int err; |
130 | |
131 | mutex_lock_nested(lock: &wbuf->io_mutex, subclass: wbuf->jhead); |
132 | err = ubifs_wbuf_sync_nolock(wbuf); |
133 | mutex_unlock(lock: &wbuf->io_mutex); |
134 | return err; |
135 | } |
136 | |
137 | /** |
138 | * ubifs_encode_dev - encode device node IDs. |
139 | * @dev: UBIFS device node information |
140 | * @rdev: device IDs to encode |
141 | * |
142 | * This is a helper function which encodes major/minor numbers of a device node |
143 | * into UBIFS device node description. We use standard Linux "new" and "huge" |
144 | * encodings. |
145 | */ |
146 | static 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 object |
155 | * @lnum: LEB to add dirty space for |
156 | * @dirty: dirty space to add |
157 | * |
158 | * This is a helper function which increased amount of dirty LEB space. Returns |
159 | * zero in case of success and a negative error code in case of failure. |
160 | */ |
161 | static 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, flags_set: 0, flags_clean: 0); |
164 | } |
165 | |
166 | /** |
167 | * ubifs_return_leb - return LEB to lprops. |
168 | * @c: the UBIFS file-system description object |
169 | * @lnum: LEB to return |
170 | * |
171 | * This helper function cleans the "taken" flag of a logical eraseblock in the |
172 | * lprops. Returns zero in case of success and a negative error code in case of |
173 | * failure. |
174 | */ |
175 | static inline int ubifs_return_leb(struct ubifs_info *c, int lnum) |
176 | { |
177 | return ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, flags_set: 0, |
178 | flags_clean: LPROPS_TAKEN, idx_gc_cnt: 0); |
179 | } |
180 | |
181 | /** |
182 | * ubifs_idx_node_sz - return index node size. |
183 | * @c: the UBIFS file-system description object |
184 | * @child_cnt: number of children of this index node |
185 | */ |
186 | static 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 object |
195 | * @idx: index node |
196 | * @bnum: branch number |
197 | */ |
198 | static inline |
199 | struct 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 object |
210 | * @idx: index node |
211 | */ |
212 | static 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 object |
221 | * @key: node key to lookup |
222 | * @node: the node is returned here |
223 | * |
224 | * This function look up and reads node with key @key. The caller has to make |
225 | * sure the @node buffer is large enough to fit the node. Returns zero in case |
226 | * of success, %-ENOENT if the node was not found, and a negative error code in |
227 | * case of failure. |
228 | */ |
229 | static 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 object |
238 | * |
239 | * This function locks lprops. Lprops have to be unlocked by |
240 | * 'ubifs_release_lprops()'. |
241 | */ |
242 | static 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 object |
250 | * |
251 | * This function has to be called after each 'ubifs_get_lprops()' call to |
252 | * unlock lprops. |
253 | */ |
254 | static 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(lock: &c->lp_mutex); |
260 | } |
261 | |
262 | /** |
263 | * ubifs_next_log_lnum - switch to the next log LEB. |
264 | * @c: UBIFS file-system description object |
265 | * @lnum: current log LEB |
266 | * |
267 | * This helper function returns the log LEB number which goes next after LEB |
268 | * 'lnum'. |
269 | */ |
270 | static 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 | |
279 | static 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 | |
287 | const char *ubifs_assert_action_name(struct ubifs_info *c); |
288 | |
289 | #endif /* __UBIFS_MISC_H__ */ |
290 | |