ref: 76109834c47842299cadf371c4906bdabe8ccd8c
dir: /lwext4/ext4_fs.h/
/* * Copyright (c) 2013 Grzegorz Kostka ([email protected]) * * * HelenOS: * Copyright (c) 2012 Martin Sucha * Copyright (c) 2012 Frantisek Princ * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * - The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /** @addtogroup lwext4 * @{ */ /** * @file ext4_fs.c * @brief More complex filesystem functions. */ #ifndef EXT4_FS_H_ #define EXT4_FS_H_ #ifdef __cplusplus extern "C" { #endif #include "ext4_config.h" #include "ext4_types.h" #include <stdint.h> #include <stdbool.h> /**@brief Convert block address to relative index in block group. * @param sb Superblock pointer * @param baddr Block number to convert * @return Relative number of block */ static inline uint32_t ext4_fs_addr_to_idx_bg(struct ext4_sblock *s, ext4_fsblk_t baddr) { if (ext4_get32(s, first_data_block)) baddr--; return baddr % ext4_get32(s, blocks_per_group); } /**@brief Convert relative block address in group to absolute address. * @param s Superblock pointer * @param index Relative block address * @param bgid Block group * @return Absolute block address */ static inline ext4_fsblk_t ext4_fs_bg_idx_to_addr(struct ext4_sblock *s, uint32_t index, uint32_t bgid) { if (ext4_get32(s, first_data_block)) index++; return ext4_get32(s, blocks_per_group) * bgid + index; } /**@brief TODO: */ static inline ext4_fsblk_t ext4_fs_first_bg_block_no(struct ext4_sblock *s, uint32_t bgid) { return (uint64_t)bgid * ext4_get32(s, blocks_per_group) + ext4_get32(s, first_data_block); } /**@brief Initialize filesystem and read all needed data. * @param fs Filesystem instance to be initialized * @param bdev Identifier if device with the filesystem * @return Error code */ int ext4_fs_init(struct ext4_fs *fs, struct ext4_blockdev *bdev); /**@brief Destroy filesystem instance (used by unmount operation). * @param fs Filesystem to be destroyed * @return Error code */ int ext4_fs_fini(struct ext4_fs *fs); /**@brief Check filesystem's features, if supported by this driver * Function can return EOK and set read_only flag. It mean's that * there are some not-supported features, that can cause problems * during some write operations. * @param fs Filesystem to be checked * @param read_only Flag if filesystem should be mounted only for reading * @return Error code */ int ext4_fs_check_features(struct ext4_fs *fs, bool *read_only); /**@brief Get reference to block group specified by index. * @param fs Filesystem to find block group on * @param bgid Index of block group to load * @param ref Output pointer for reference * @return Error code */ int ext4_fs_get_block_group_ref(struct ext4_fs *fs, uint32_t bgid, struct ext4_block_group_ref *ref); /**@brief Put reference to block group. * @param ref Pointer for reference to be put back * @return Error code */ int ext4_fs_put_block_group_ref(struct ext4_block_group_ref *ref); /**@brief Get reference to i-node specified by index. * @param fs Filesystem to find i-node on * @param index Index of i-node to load * @param ref Output pointer for reference * @return Error code */ int ext4_fs_get_inode_ref(struct ext4_fs *fs, uint32_t index, struct ext4_inode_ref *ref); /**@brief Reset blocks field of i-node. * @param fs Filesystem to reset blocks field of i-inode on * @param inode_ref ref Pointer for inode to be operated on */ void ext4_fs_inode_blocks_init(struct ext4_fs *fs, struct ext4_inode_ref *inode_ref); /**@brief Put reference to i-node. * @param ref Pointer for reference to be put back * @return Error code */ int ext4_fs_put_inode_ref(struct ext4_inode_ref *ref); /**@brief Convert filetype to inode mode. * @param filetype * @return inode mode */ uint32_t ext4_fs_correspond_inode_mode(int filetype); /**@brief Allocate new i-node in the filesystem. * @param fs Filesystem to allocated i-node on * @param inode_ref Output pointer to return reference to allocated i-node * @param filetype File type of newly created i-node * @return Error code */ int ext4_fs_alloc_inode(struct ext4_fs *fs, struct ext4_inode_ref *inode_ref, int filetype); /**@brief Release i-node and mark it as free. * @param inode_ref I-node to be released * @return Error code */ int ext4_fs_free_inode(struct ext4_inode_ref *inode_ref); /**@brief Truncate i-node data blocks. * @param inode_ref I-node to be truncated * @param new_size New size of inode (must be < current size) * @return Error code */ int ext4_fs_truncate_inode(struct ext4_inode_ref *inode_ref, uint64_t new_size); /**@brief Compute 'goal' for inode index * @param inode_ref Reference to inode, to allocate block for * @return goal */ ext4_fsblk_t ext4_fs_inode_to_goal_block(struct ext4_inode_ref *inode_ref); /**@brief Compute 'goal' for allocation algorithm (For blockmap). * @param inode_ref Reference to inode, to allocate block for * @param goal * @return error code */ int ext4_fs_indirect_find_goal(struct ext4_inode_ref *inode_ref, ext4_fsblk_t *goal); /**@brief Get physical block address by logical index of the block. * @param inode_ref I-node to read block address from * @param iblock Logical index of block * @param fblock Output pointer for return physical * block address * @param support_unwritten Indicate whether unwritten block range * is supported under the current context * @return Error code */ int ext4_fs_get_inode_data_block_index(struct ext4_inode_ref *inode_ref, uint64_t iblock, ext4_fsblk_t *fblock, bool support_unwritten); /**@brief Initialize a part of unwritten range of the inode. * @param inode_ref I-node to proceed on. * @param iblock Logical index of block * @param fblock Output pointer for return physical block address * @return Error code */ int ext4_fs_init_inode_data_block_index(struct ext4_inode_ref *inode_ref, uint64_t iblock, ext4_fsblk_t *fblock); /**@brief Append following logical block to the i-node. * @param inode_ref I-node to append block to * @param fblock Output physical block address of newly allocated block * @param iblock Output logical number of newly allocated block * @return Error code */ int ext4_fs_append_inode_block(struct ext4_inode_ref *inode_ref, ext4_fsblk_t *fblock, uint32_t *iblock); /**@brief Increment inode link count. * @param inode none handle */ void ext4_fs_inode_links_count_inc(struct ext4_inode_ref *inode_ref); /**@brief Decrement inode link count. * @param inode none handle */ void ext4_fs_inode_links_count_dec(struct ext4_inode_ref *inode_ref); #ifdef __cplusplus } #endif #endif /* EXT4_FS_H_ */ /** * @} */