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
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.
34 /** @addtogroup lwext4
39 * @brief Superblock operations.
45 #include <ext4_config.h>
46 #include <ext4_types.h>
48 /**@brief Blocks count get stored in superblock.
49 * @param s superblock descriptor
50 * @return count of blocks*/
51 static inline uint64_t ext4_sb_get_blocks_cnt(struct ext4_sblock *s)
53 return ((uint64_t)to_le32(s->blocks_count_hi) << 32) |
54 to_le32(s->blocks_count_lo);
57 /**@brief Free blocks count get stored in superblock.
58 * @param s superblock descriptor
59 * @return free blocks*/
60 static inline uint64_t ext4_sb_get_free_blocks_cnt(struct ext4_sblock *s)
62 return ((uint64_t)to_le32(s->free_blocks_count_hi) << 32) |
63 to_le32(s->free_blocks_count_lo);
66 /**@brief Free blocks count set.
67 * @param s superblock descriptor
68 * @param cnt new value of free blocks*/
69 static inline void ext4_sb_set_free_blocks_cnt(struct ext4_sblock *s,
72 s->free_blocks_count_lo = to_le32((cnt << 32) >> 32);
73 s->free_blocks_count_hi = to_le32(cnt >> 32);
76 /**@brief Block size get from superblock.
77 * @param s superblock descriptor
78 * @return block size in bytes*/
79 static inline uint32_t ext4_sb_get_block_size(struct ext4_sblock *s)
81 return 1024 << to_le32(s->log_block_size);
84 /**@brief Block group descriptor size.
85 * @param s superblock descriptor
86 * @return block group descriptor size in bytes*/
87 static inline uint16_t ext4_sb_get_desc_size(struct ext4_sblock *s)
89 uint16_t size = to_le16(s->desc_size);
91 return size < EXT4_MIN_BLOCK_GROUP_DESCRIPTOR_SIZE
92 ? EXT4_MIN_BLOCK_GROUP_DESCRIPTOR_SIZE
96 /*************************Flags and features*********************************/
98 /**@brief Support check of flag.
99 * @param s superblock descriptor
100 * @param v flag to check
101 * @return true if flag is supported*/
102 static inline bool ext4_sb_check_flag(struct ext4_sblock *s, uint32_t v)
104 return to_le32(s->flags) & v;
107 /**@brief Support check of feature compatible.
108 * @param s superblock descriptor
109 * @param v feature to check
110 * @return true if feature is supported*/
111 static inline bool ext4_sb_has_feature_compatible(struct ext4_sblock *s,
114 return to_le32(s->features_compatible) & v;
117 /**@brief Support check of feature incompatible.
118 * @param s superblock descriptor
119 * @param v feature to check
120 * @return true if feature is supported*/
121 static inline bool ext4_sb_has_feature_incompatible(struct ext4_sblock *s,
124 return to_le32(s->features_incompatible) & v;
127 /**@brief Support check of read only flag.
128 * @param s superblock descriptor
129 * @param v flag to check
130 * @return true if flag is supported*/
131 static inline bool ext4_sb_has_feature_read_only(struct ext4_sblock *s,
134 return to_le32(s->features_read_only) & v;
137 /**@brief Block group to flex group.
138 * @param s superblock descriptor
139 * @param block_group block group
140 * @return flex group id*/
141 static inline uint32_t ext4_sb_bg_to_flex(struct ext4_sblock *s,
142 uint32_t block_group)
144 return block_group >> to_le32(s->log_groups_per_flex);
147 /**@brief Flex block group size.
148 * @param s superblock descriptor
149 * @return flex bg size*/
150 static inline uint32_t ext4_sb_flex_bg_size(struct ext4_sblock *s)
152 return 1 << to_le32(s->log_groups_per_flex);
155 /**@brief Return first meta block group id.
156 * @param s superblock descriptor
157 * @return first meta_bg id */
158 static inline uint32_t ext4_sb_first_meta_bg(struct ext4_sblock *s)
160 return to_le32(s->first_meta_bg);
163 /**************************More complex functions****************************/
165 /**@brief Returns a block group count.
166 * @param s superblock descriptor
167 * @return count of block groups*/
168 uint32_t ext4_block_group_cnt(struct ext4_sblock *s);
170 /**@brief Returns block count in block group
171 * (last block group may have less blocks)
172 * @param s superblock descriptor
173 * @param bgid block group id
174 * @return blocks count*/
175 uint32_t ext4_blocks_in_group_cnt(struct ext4_sblock *s, uint32_t bgid);
177 /**@brief Returns inodes count in block group
178 * (last block group may have less inodes)
179 * @param s superblock descriptor
180 * @param bgid block group id
181 * @return inodes count*/
182 uint32_t ext4_inodes_in_group_cnt(struct ext4_sblock *s, uint32_t bgid);
184 /***************************Read/write/check superblock**********************/
186 /**@brief Superblock write.
187 * @param bdev block device descriptor.
188 * @param s superblock descruptor
189 * @return Standard error code */
190 int ext4_sb_write(struct ext4_blockdev *bdev, struct ext4_sblock *s);
192 /**@brief Superblock read.
193 * @param bdev block device descriptor.
194 * @param s superblock descruptor
195 * @return Standard error code */
196 int ext4_sb_read(struct ext4_blockdev *bdev, struct ext4_sblock *s);
198 /**@brief Superblock simple validation.
199 * @param s superblock dsecriptor
200 * @return true if OK*/
201 bool ext4_sb_check(struct ext4_sblock *s);
203 /**@brief Superblock presence in block group.
204 * @param s superblock dsecriptor
205 * @param block_group block group id
206 * @return true if block group has superblock*/
207 bool ext4_sb_is_super_in_bg(struct ext4_sblock *s, uint32_t block_group);
210 uint32_t ext4_bg_num_gdb(struct ext4_sblock *s, uint32_t group);
213 uint32_t ext4_num_base_meta_clusters(struct ext4_sblock *s,
214 uint32_t block_group);
216 #endif /* EXT4_SUPER_H_ */