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.
46 #include <ext4_config.h>
47 #include <ext4_types.h>
50 /****************************Unstandard access to superblock*****************/
52 /**@brief Blocks count get stored in superblock.
53 * @param s superblock descriptor
54 * @return count of blocks*/
55 static inline uint64_t ext4_sb_get_blocks_cnt(struct ext4_sblock *s)
57 return ((uint64_t) to_le32(s->blocks_count_hi) << 32) |
58 to_le32(s->blocks_count_lo);
61 /**@brief Free blocks count get stored in superblock.
62 * @param s superblock descriptor
63 * @return free blocks*/
64 static inline uint64_t ext4_sb_get_free_blocks_cnt(struct ext4_sblock *s)
66 return ((uint64_t) to_le32(s->free_blocks_count_hi) << 32) |
67 to_le32(s->free_blocks_count_lo);
70 /**@brief Free blocks count set.
71 * @param s superblock descriptor
72 * @param cnt new value of free blocks*/
73 static inline void ext4_sb_set_free_blocks_cnt(struct ext4_sblock *s,
76 s->free_blocks_count_lo = to_le32((cnt << 32) >> 32);
77 s->free_blocks_count_hi = to_le32(cnt >> 32);
80 /**@brief Block size get from superblock.
81 * @param s superblock descriptor
82 * @return block size in bytes*/
83 static inline uint32_t ext4_sb_get_block_size(struct ext4_sblock *s)
85 return 1024 << to_le32(s->log_block_size);
88 /**@brief Block group descriptor size.
89 * @param s superblock descriptor
90 * @return block group descriptor size in bytes*/
91 static inline uint16_t ext4_sb_get_desc_size(struct ext4_sblock *s)
93 uint16_t size = to_le16(s->desc_size);
95 return size < EXT4_MIN_BLOCK_GROUP_DESCRIPTOR_SIZE ?
96 EXT4_MIN_BLOCK_GROUP_DESCRIPTOR_SIZE : size;
99 /*************************Flags and features*********************************/
101 /**@brief Support check of flag.
102 * @param s superblock descriptor
103 * @param v flag to check
104 * @return true if flag is supported*/
105 static inline bool ext4_sb_check_flag(struct ext4_sblock *s, uint32_t v)
107 return to_le32(s->flags) & v;
110 /**@brief Support check of feature compatible.
111 * @param s superblock descriptor
112 * @param v feature to check
113 * @return true if feature is supported*/
114 static inline bool ext4_sb_check_feature_compatible(struct ext4_sblock *s,
117 return to_le32(s->features_compatible) & v;
121 /**@brief Support check of feature incompatible.
122 * @param s superblock descriptor
123 * @param v feature to check
124 * @return true if feature is supported*/
125 static inline bool ext4_sb_check_feature_incompatible(struct ext4_sblock *s,
128 return to_le32(s->features_incompatible) & v;
132 /**@brief Support check of read only flag.
133 * @param s superblock descriptor
134 * @param v flag to check
135 * @return true if flag is supported*/
136 static inline bool ext4_sb_check_read_only(struct ext4_sblock *s, uint32_t v)
138 return to_le32(s->features_read_only) & v;
141 /**************************More complex functions****************************/
143 /**@brief Returns a block group count.
144 * @param s superblock descriptor
145 * @return count of block groups*/
146 uint32_t ext4_block_group_cnt(struct ext4_sblock *s);
148 /**@brief Returns block count in block group
149 * (last block group may have less blocks)
150 * @param s superblock descriptor
151 * @param bgid block group id
152 * @return blocks count*/
153 uint32_t ext4_blocks_in_group_cnt(struct ext4_sblock *s, uint32_t bgid);
155 /**@brief Returns inodes count in block group
156 * (last block group may have less inodes)
157 * @param s superblock descriptor
158 * @param bgid block group id
159 * @return inodes count*/
160 uint32_t ext4_inodes_in_group_cnt(struct ext4_sblock *s, uint32_t bgid);
162 /***************************Read/write/check superblock**********************/
164 /**@brief Superblock write.
165 * @param bdev block device descriptor.
166 * @param s superblock descruptor
167 * @return Standard error code */
168 int ext4_sb_write(struct ext4_blockdev *bdev, struct ext4_sblock *s);
170 /**@brief Superblock read.
171 * @param bdev block device descriptor.
172 * @param s superblock descruptor
173 * @return Standard error code */
174 int ext4_sb_read(struct ext4_blockdev *bdev, struct ext4_sblock *s);
176 /**@brief Superblock simple validation.
177 * @param s superblock dsecriptor
178 * @return true if OK*/
179 bool ext4_sb_check(struct ext4_sblock *s);
182 #endif /* EXT4_SUPER_H_ */