2 * Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
6 * Copyright (c) 2012 Martin Sucha
7 * Copyright (c) 2012 Frantisek Princ
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
14 * - Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * - Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * - The name of the author may not be used to endorse or promote products
20 * derived from this software without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 /** @addtogroup lwext4
39 * @brief More complex filesystem functions.
49 #include "ext4_config.h"
50 #include "ext4_types.h"
51 #include "ext4_misc.h"
59 struct ext4_blockdev *bdev;
60 struct ext4_sblock sb;
62 uint64_t inode_block_limits[4];
63 uint64_t inode_blocks_per_level[4];
65 uint32_t last_inode_bg_id;
67 struct jbd_fs *jbd_fs;
68 struct jbd_journal *jbd_journal;
69 struct jbd_trans *curr_trans;
72 struct ext4_block_group_ref {
73 struct ext4_block block;
74 struct ext4_bgroup *block_group;
80 struct ext4_inode_ref {
81 struct ext4_block block;
82 struct ext4_inode *inode;
89 /**@brief Convert block address to relative index in block group.
90 * @param sb Superblock pointer
91 * @param baddr Block number to convert
92 * @return Relative number of block
94 static inline uint32_t ext4_fs_addr_to_idx_bg(struct ext4_sblock *s,
97 if (ext4_get32(s, first_data_block) && baddr)
100 return baddr % ext4_get32(s, blocks_per_group);
103 /**@brief Convert relative block address in group to absolute address.
104 * @param s Superblock pointer
105 * @param index Relative block address
106 * @param bgid Block group
107 * @return Absolute block address
109 static inline ext4_fsblk_t ext4_fs_bg_idx_to_addr(struct ext4_sblock *s,
113 if (ext4_get32(s, first_data_block))
116 return ext4_get32(s, blocks_per_group) * bgid + index;
120 static inline ext4_fsblk_t ext4_fs_first_bg_block_no(struct ext4_sblock *s,
123 return (uint64_t)bgid * ext4_get32(s, blocks_per_group) +
124 ext4_get32(s, first_data_block);
127 /**@brief Initialize filesystem and read all needed data.
128 * @param fs Filesystem instance to be initialized
129 * @param bdev Identifier if device with the filesystem
130 * @param read_only Mark the filesystem as read-only.
133 int ext4_fs_init(struct ext4_fs *fs, struct ext4_blockdev *bdev,
136 /**@brief Destroy filesystem instance (used by unmount operation).
137 * @param fs Filesystem to be destroyed
140 int ext4_fs_fini(struct ext4_fs *fs);
142 /**@brief Check filesystem's features, if supported by this driver
143 * Function can return EOK and set read_only flag. It mean's that
144 * there are some not-supported features, that can cause problems
145 * during some write operations.
146 * @param fs Filesystem to be checked
147 * @param read_only Flag if filesystem should be mounted only for reading
150 int ext4_fs_check_features(struct ext4_fs *fs, bool *read_only);
152 /**@brief Get reference to block group specified by index.
153 * @param fs Filesystem to find block group on
154 * @param bgid Index of block group to load
155 * @param ref Output pointer for reference
158 int ext4_fs_get_block_group_ref(struct ext4_fs *fs, uint32_t bgid,
159 struct ext4_block_group_ref *ref);
161 /**@brief Put reference to block group.
162 * @param ref Pointer for reference to be put back
165 int ext4_fs_put_block_group_ref(struct ext4_block_group_ref *ref);
167 /**@brief Get reference to i-node specified by index.
168 * @param fs Filesystem to find i-node on
169 * @param index Index of i-node to load
170 * @param ref Output pointer for reference
173 int ext4_fs_get_inode_ref(struct ext4_fs *fs, uint32_t index,
174 struct ext4_inode_ref *ref);
176 /**@brief Reset blocks field of i-node.
177 * @param fs Filesystem to reset blocks field of i-inode on
178 * @param inode_ref ref Pointer for inode to be operated on
180 void ext4_fs_inode_blocks_init(struct ext4_fs *fs,
181 struct ext4_inode_ref *inode_ref);
183 /**@brief Put reference to i-node.
184 * @param ref Pointer for reference to be put back
187 int ext4_fs_put_inode_ref(struct ext4_inode_ref *ref);
189 /**@brief Convert filetype to inode mode.
193 uint32_t ext4_fs_correspond_inode_mode(int filetype);
195 /**@brief Allocate new i-node in the filesystem.
196 * @param fs Filesystem to allocated i-node on
197 * @param inode_ref Output pointer to return reference to allocated i-node
198 * @param filetype File type of newly created i-node
201 int ext4_fs_alloc_inode(struct ext4_fs *fs, struct ext4_inode_ref *inode_ref,
204 /**@brief Release i-node and mark it as free.
205 * @param inode_ref I-node to be released
208 int ext4_fs_free_inode(struct ext4_inode_ref *inode_ref);
210 /**@brief Truncate i-node data blocks.
211 * @param inode_ref I-node to be truncated
212 * @param new_size New size of inode (must be < current size)
215 int ext4_fs_truncate_inode(struct ext4_inode_ref *inode_ref, uint64_t new_size);
217 /**@brief Compute 'goal' for inode index
218 * @param inode_ref Reference to inode, to allocate block for
221 ext4_fsblk_t ext4_fs_inode_to_goal_block(struct ext4_inode_ref *inode_ref);
223 /**@brief Compute 'goal' for allocation algorithm (For blockmap).
224 * @param inode_ref Reference to inode, to allocate block for
228 int ext4_fs_indirect_find_goal(struct ext4_inode_ref *inode_ref,
231 /**@brief Get physical block address by logical index of the block.
232 * @param inode_ref I-node to read block address from
233 * @param iblock Logical index of block
234 * @param fblock Output pointer for return physical
236 * @param support_unwritten Indicate whether unwritten block range
237 * is supported under the current context
240 int ext4_fs_get_inode_dblk_idx(struct ext4_inode_ref *inode_ref,
241 ext4_lblk_t iblock, ext4_fsblk_t *fblock,
242 bool support_unwritten);
244 /**@brief Initialize a part of unwritten range of the inode.
245 * @param inode_ref I-node to proceed on.
246 * @param iblock Logical index of block
247 * @param fblock Output pointer for return physical block address
250 int ext4_fs_init_inode_dblk_idx(struct ext4_inode_ref *inode_ref,
251 ext4_lblk_t iblock, ext4_fsblk_t *fblock);
253 /**@brief Append following logical block to the i-node.
254 * @param inode_ref I-node to append block to
255 * @param fblock Output physical block address of newly allocated block
256 * @param iblock Output logical number of newly allocated block
259 int ext4_fs_append_inode_dblk(struct ext4_inode_ref *inode_ref,
260 ext4_fsblk_t *fblock, ext4_lblk_t *iblock);
262 /**@brief Increment inode link count.
263 * @param inode none handle
265 void ext4_fs_inode_links_count_inc(struct ext4_inode_ref *inode_ref);
267 /**@brief Decrement inode link count.
268 * @param inode none handle
270 void ext4_fs_inode_links_count_dec(struct ext4_inode_ref *inode_ref);
276 #endif /* EXT4_FS_H_ */