1/*
2 * Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
3 *
4 *
5 * HelenOS:
6 * Copyright (c) 2012 Martin Sucha
7 * Copyright (c) 2012 Frantisek Princ
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 *
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.
21 *
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
29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34/** @addtogroup lwext4
35 * @{
36 */
37/**
38 * @file ext4_fs.c
39 * @brief More complex filesystem functions.
40 */
41
42#ifndef EXT4_FS_H_
43#define EXT4_FS_H_
44
45#ifdef __cplusplus
46extern "C" {
47#endif
48
49#include <ext4_config.h>
50#include <ext4_types.h>
51#include <ext4_misc.h>
52
53#include <stdint.h>
54#include <stdbool.h>
55
56struct ext4_fs {
57 bool read_only;
58
59 struct ext4_blockdev *bdev;
60 struct ext4_sblock sb;
61
62 uint64_t inode_block_limits[4];
63 uint64_t inode_blocks_per_level[4];
64
65 uint32_t last_inode_bg_id;
66
67 struct jbd_fs *jbd_fs;
68 struct jbd_journal *jbd_journal;
69 struct jbd_trans *curr_trans;
70};
71
72struct ext4_block_group_ref {
73 struct ext4_block block;
74 struct ext4_bgroup *block_group;
75 struct ext4_fs *fs;
76 uint32_t index;
77 bool dirty;
78};
79
80struct ext4_inode_ref {
81 struct ext4_block block;
82 struct ext4_inode *inode;
83 struct ext4_fs *fs;
84 uint32_t index;
85 bool dirty;
86};
87
88
89/**@brief Convert block address to relative index in block group.
90 * @param s Superblock pointer
91 * @param baddr Block number to convert
92 * @return Relative number of block
93 */
94static inline uint32_t ext4_fs_addr_to_idx_bg(struct ext4_sblock *s,
95 ext4_fsblk_t baddr)
96{
97 if (ext4_get32(s, first_data_block) && baddr)
98 baddr--;
99
100 return baddr % ext4_get32(s, blocks_per_group);
101}
102
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
108 */
109static inline ext4_fsblk_t ext4_fs_bg_idx_to_addr(struct ext4_sblock *s,
110 uint32_t index,
111 uint32_t bgid)
112{
113 if (ext4_get32(s, first_data_block))
114 index++;
115
116 return ext4_get32(s, blocks_per_group) * bgid + index;
117}
118
119/**@brief TODO: */
120static inline ext4_fsblk_t ext4_fs_first_bg_block_no(struct ext4_sblock *s,
121 uint32_t bgid)
122{
123 return (uint64_t)bgid * ext4_get32(s, blocks_per_group) +
124 ext4_get32(s, first_data_block);
125}
126
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.
131 * @return Error code
132 */
133int ext4_fs_init(struct ext4_fs *fs, struct ext4_blockdev *bdev,
134 bool read_only);
135
136/**@brief Destroy filesystem instance (used by unmount operation).
137 * @param fs Filesystem to be destroyed
138 * @return Error code
139 */
140int ext4_fs_fini(struct ext4_fs *fs);
141
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
148 * @return Error code
149 */
150int ext4_fs_check_features(struct ext4_fs *fs, bool *read_only);
151
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
156 * @return Error code
157 */
158int ext4_fs_get_block_group_ref(struct ext4_fs *fs, uint32_t bgid,
159 struct ext4_block_group_ref *ref);
160
161/**@brief Put reference to block group.
162 * @param ref Pointer for reference to be put back
163 * @return Error code
164 */
165int ext4_fs_put_block_group_ref(struct ext4_block_group_ref *ref);
166
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
171 * @return Error code
172 */
173int ext4_fs_get_inode_ref(struct ext4_fs *fs, uint32_t index,
174 struct ext4_inode_ref *ref);
175
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
179 */
180void ext4_fs_inode_blocks_init(struct ext4_fs *fs,
181 struct ext4_inode_ref *inode_ref);
182
183/**@brief Put reference to i-node.
184 * @param ref Pointer for reference to be put back
185 * @return Error code
186 */
187int ext4_fs_put_inode_ref(struct ext4_inode_ref *ref);
188
189/**@brief Convert filetype to inode mode.
190 * @param filetype File type
191 * @return inode mode
192 */
193uint32_t ext4_fs_correspond_inode_mode(int filetype);
194
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
199 * @return Error code
200 */
201int ext4_fs_alloc_inode(struct ext4_fs *fs, struct ext4_inode_ref *inode_ref,
202 int filetype);
203
204/**@brief Release i-node and mark it as free.
205 * @param inode_ref I-node to be released
206 * @return Error code
207 */
208int ext4_fs_free_inode(struct ext4_inode_ref *inode_ref);
209
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)
213 * @return Error code
214 */
215int ext4_fs_truncate_inode(struct ext4_inode_ref *inode_ref, uint64_t new_size);
216
217/**@brief Compute 'goal' for inode index
218 * @param inode_ref Reference to inode, to allocate block for
219 * @return goal
220 */
221ext4_fsblk_t ext4_fs_inode_to_goal_block(struct ext4_inode_ref *inode_ref);
222
223/**@brief Compute 'goal' for allocation algorithm (For blockmap).
224 * @param inode_ref Reference to inode, to allocate block for
225 * @return error code
226 */
227int ext4_fs_indirect_find_goal(struct ext4_inode_ref *inode_ref,
228 ext4_fsblk_t *goal);
229
230/**@brief Get physical block address by logical index of the block.
231 * @param inode_ref I-node to read block address from
232 * @param iblock Logical index of block
233 * @param fblock Output pointer for return physical
234 * block address
235 * @param support_unwritten Indicate whether unwritten block range
236 * is supported under the current context
237 * @return Error code
238 */
239int ext4_fs_get_inode_dblk_idx(struct ext4_inode_ref *inode_ref,
240 ext4_lblk_t iblock, ext4_fsblk_t *fblock,
241 bool support_unwritten);
242
243/**@brief Initialize a part of unwritten range of the inode.
244 * @param inode_ref I-node to proceed on.
245 * @param iblock Logical index of block
246 * @param fblock Output pointer for return physical block address
247 * @return Error code
248 */
249int ext4_fs_init_inode_dblk_idx(struct ext4_inode_ref *inode_ref,
250 ext4_lblk_t iblock, ext4_fsblk_t *fblock);
251
252/**@brief Append following logical block to the i-node.
253 * @param inode_ref I-node to append block to
254 * @param fblock Output physical block address of newly allocated block
255 * @param iblock Output logical number of newly allocated block
256 * @return Error code
257 */
258int ext4_fs_append_inode_dblk(struct ext4_inode_ref *inode_ref,
259 ext4_fsblk_t *fblock, ext4_lblk_t *iblock);
260
261/**@brief Increment inode link count.
262 * @param inode_ref none handle
263 */
264void ext4_fs_inode_links_count_inc(struct ext4_inode_ref *inode_ref);
265
266/**@brief Decrement inode link count.
267 * @param inode_ref none handle
268 */
269void ext4_fs_inode_links_count_dec(struct ext4_inode_ref *inode_ref);
270
271#ifdef __cplusplus
272}
273#endif
274
275#endif /* EXT4_FS_H_ */
276
277/**
278 * @}
279 */
280