/* * This file is part of UBIFS. * * Copyright (C) 2006-2008 Nokia Corporation * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published by * the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program; if not, write to the Free Software Foundation, Inc., 51 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * * Authors: Artem Bityutskiy (Битюцкий Артём) * Adrian Hunter */ /* * This file contains miscellaneous helper functions. */ #ifndef __UBIFS_MISC_H__ #define __UBIFS_MISC_H__ /** * ubifs_zn_dirty - check if znode is dirty. * @znode: znode to check * * This helper function returns %1 if @znode is dirty and %0 otherwise. */ static inline int ubifs_zn_dirty(const struct ubifs_znode *znode) { return !!test_bit(DIRTY_ZNODE, &znode->flags); } /** * ubifs_wake_up_bgt - wake up background thread. * @c: UBIFS file-system description object */ static inline void ubifs_wake_up_bgt(struct ubifs_info *c) { if (c->bgt && !c->need_bgt) { c->need_bgt = 1; wake_up_process(c->bgt); } } /** * ubifs_tnc_find_child - find next child in znode. * @znode: znode to search at * @start: the zbranch index to start at * * This helper function looks for znode child starting at index @start. Returns * the child or %NULL if no children were found. */ static inline struct ubifs_znode * ubifs_tnc_find_child(struct ubifs_znode *znode, int start) { while (start < znode->child_cnt) { if (znode->zbranch[start].znode) return znode->zbranch[start].znode; start += 1; } return NULL; } /** * ubifs_inode - get UBIFS inode information by VFS 'struct inode' object. * @inode: the VFS 'struct inode' pointer */ static inline struct ubifs_inode *ubifs_inode(const struct inode *inode) { return container_of(inode, struct ubifs_inode, vfs_inode); } /** * ubifs_compr_present - check if compressor was compiled in. * @compr_type: compressor type to check * * This function returns %1 of compressor of type @compr_type is present, and * %0 if not. */ static inline int ubifs_compr_present(int compr_type) { ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT); return !!ubifs_compressors[compr_type]->capi_name; } /** * ubifs_compr_name - get compressor name string by its type. * @compr_type: compressor type * * This function returns compressor type string. */ static inline const char *ubifs_compr_name(int compr_type) { ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT); return ubifs_compressors[compr_type]->name; } /** * ubifs_wbuf_sync - synchronize write-buffer. * @wbuf: write-buffer to synchronize * * This is the same as as 'ubifs_wbuf_sync_nolock()' but it does not assume * that the write-buffer is already locked. */ static inline int ubifs_wbuf_sync(struct ubifs_wbuf *wbuf) { int err; mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead); err = ubifs_wbuf_sync_nolock(wbuf); mutex_unlock(&wbuf->io_mutex); return err; } /** * ubifs_leb_unmap - unmap an LEB. * @c: UBIFS file-system description object * @lnum: LEB number to unmap * * This function returns %0 on success and a negative error code on failure. */ static inline int ubifs_leb_unmap(const struct ubifs_info *c, int lnum) { int err; ubifs_assert(!c->ro_media); if (c->ro_error) return -EROFS; err = ubi_leb_unmap(c->ubi, lnum); if (err) { ubifs_err("unmap LEB %d failed, error %d", lnum, err); return err; } return 0; } /** * ubifs_leb_write - write to a LEB. * @c: UBIFS file-system description object * @lnum: LEB number to write * @buf: buffer to write from * @offs: offset within LEB to write to * @len: length to write * @dtype: data type * * This function returns %0 on success and a negative error code on failure. */ static inline int ubifs_leb_write(const struct ubifs_info *c, int lnum, const void *buf, int offs, int len, int dtype) { int err; ubifs_assert(!c->ro_media); if (c->ro_error) return -EROFS; err = ubi_leb_write(c->ubi, lnum, buf, offs, len, dtype); if (err) { ubifs_err("writing %d bytes at %d:%d, error %d", len, lnum, offs, err); return err; } return 0; } /** * ubifs_leb_change - atomic LEB change. * @c: UBIFS file-system description object * @lnum: LEB number to write * @buf: buffer to write from * @len: length to write * @dtype: data type * * This function returns %0 on success and a negative error code on failure. */ static inline int ubifs_leb_change(const struct ubifs_info *c, int lnum, const void *buf, int len, int dtype) { int err; ubifs_assert(!c->ro_media); if (c->ro_error) return -EROFS; err = ubi_leb_change(c->ubi, lnum, buf, len, dtype); if (err) { ubifs_err("changing %d bytes in LEB %d, error %d", len, lnum, err); return err; } return 0; } /** * ubifs_encode_dev - encode device node IDs. * @dev: UBIFS device node information * @rdev: device IDs to encode * * This is a helper function which encodes major/minor numbers of a device node * into UBIFS device node description. We use standard Linux "new" and "huge" * encodings. */ static inline int ubifs_encode_dev(union ubifs_dev_desc *dev, dev_t rdev) { if (new_valid_dev(rdev)) { dev->new = cpu_to_le32(new_encode_dev(rdev)); return sizeof(dev->new); } else { dev->huge = cpu_to_le64(huge_encode_dev(rdev)); return sizeof(dev->huge); } } /** * ubifs_add_dirt - add dirty space to LEB properties. * @c: the UBIFS file-system description object * @lnum: LEB to add dirty space for * @dirty: dirty space to add * * This is a helper function which increased amount of dirty LEB space. Returns * zero in case of success and a negative error code in case of failure. */ static inline int ubifs_add_dirt(struct ubifs_info *c, int lnum, int dirty) { return ubifs_update_one_lp(c, lnum, LPROPS_NC, dirty, 0, 0); } /** * ubifs_return_leb - return LEB to lprops. * @c: the UBIFS file-system description object * @lnum: LEB to return * * This helper function cleans the "taken" flag of a logical eraseblock in the * lprops. Returns zero in case of success and a negative error code in case of * failure. */ static inline int ubifs_return_leb(struct ubifs_info *c, int lnum) { return ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0, LPROPS_TAKEN, 0); } /** * ubifs_idx_node_sz - return index node size. * @c: the UBIFS file-system description object * @child_cnt: number of children of this index node */ static inline int ubifs_idx_node_sz(const struct ubifs_info *c, int child_cnt) { return UBIFS_IDX_NODE_SZ + (UBIFS_BRANCH_SZ + c->key_len) * child_cnt; } /** * ubifs_idx_branch - return pointer to an index branch. * @c: the UBIFS file-system description object * @idx: index node * @bnum: branch number */ static inline struct ubifs_branch *ubifs_idx_branch(const struct ubifs_info *c, const struct ubifs_idx_node *idx, int bnum) { return (struct ubifs_branch *)((void *)idx->branches + (UBIFS_BRANCH_SZ + c->key_len) * bnum); } /** * ubifs_idx_key - return pointer to an index key. * @c: the UBIFS file-system description object * @idx: index node */ static inline void *ubifs_idx_key(const struct ubifs_info *c, const struct ubifs_idx_node *idx) { return (void *)((struct ubifs_branch *)idx->branches)->key; } /** * ubifs_current_time - round current time to time granularity. * @inode: inode */ static inline struct timespec ubifs_current_time(struct inode *inode) { return (inode->i_sb->s_time_gran < NSEC_PER_SEC) ? current_fs_time(inode->i_sb) : CURRENT_TIME_SEC; } /** * ubifs_tnc_lookup - look up a file-system node. * @c: UBIFS file-system description object * @key: node key to lookup * @node: the node is returned here * * This function look up and reads node with key @key. The caller has to make * sure the @node buffer is large enough to fit the node. Returns zero in case * of success, %-ENOENT if the node was not found, and a negative error code in * case of failure. */ static inline int ubifs_tnc_lookup(struct ubifs_info *c, const union ubifs_key *key, void *node) { return ubifs_tnc_locate(c, key, node, NULL, NULL); } /** * ubifs_get_lprops - get reference to LEB properties. * @c: the UBIFS file-system description object * * This function locks lprops. Lprops have to be unlocked by * 'ubifs_release_lprops()'. */ static inline void ubifs_get_lprops(struct ubifs_info *c) { mutex_lock(&c->lp_mutex); } /** * ubifs_release_lprops - release lprops lock. * @c: the UBIFS file-system description object * * This function has to be called after each 'ubifs_get_lprops()' call to * unlock lprops. */ static inline void ubifs_release_lprops(struct ubifs_info *c) { ubifs_assert(mutex_is_locked(&c->lp_mutex)); ubifs_assert(c->lst.empty_lebs >= 0 && c->lst.empty_lebs <= c->main_lebs); mutex_unlock(&c->lp_mutex); } #endif /* __UBIFS_MISC_H__ */