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_feature_com(struct ext4_sblock *s, uint32_t v)
113 return to_le32(s->features_compatible) & v;
116 /**@brief Support check of feature incompatible.
117 * @param s superblock descriptor
118 * @param v feature to check
119 * @return true if feature is supported*/
120 static inline bool ext4_sb_feature_incom(struct ext4_sblock *s, uint32_t v)
122 return to_le32(s->features_incompatible) & v;
125 /**@brief Support check of read only flag.
126 * @param s superblock descriptor
127 * @param v flag to check
128 * @return true if flag is supported*/
129 static inline bool ext4_sb_feature_ro_com(struct ext4_sblock *s, uint32_t v)
131 return to_le32(s->features_read_only) & v;
134 /**@brief Block group to flex group.
135 * @param s superblock descriptor
136 * @param block_group block group
137 * @return flex group id*/
138 static inline uint32_t ext4_sb_bg_to_flex(struct ext4_sblock *s,
139 uint32_t block_group)
141 return block_group >> to_le32(s->log_groups_per_flex);
144 /**@brief Flex block group size.
145 * @param s superblock descriptor
146 * @return flex bg size*/
147 static inline uint32_t ext4_sb_flex_bg_size(struct ext4_sblock *s)
149 return 1 << to_le32(s->log_groups_per_flex);
152 /**@brief Return first meta block group id.
153 * @param s superblock descriptor
154 * @return first meta_bg id */
155 static inline uint32_t ext4_sb_first_meta_bg(struct ext4_sblock *s)
157 return to_le32(s->first_meta_bg);
160 /**************************More complex functions****************************/
162 /**@brief Returns a block group count.
163 * @param s superblock descriptor
164 * @return count of block groups*/
165 uint32_t ext4_block_group_cnt(struct ext4_sblock *s);
167 /**@brief Returns block count in block group
168 * (last block group may have less blocks)
169 * @param s superblock descriptor
170 * @param bgid block group id
171 * @return blocks count*/
172 uint32_t ext4_blocks_in_group_cnt(struct ext4_sblock *s, uint32_t bgid);
174 /**@brief Returns inodes count in block group
175 * (last block group may have less inodes)
176 * @param s superblock descriptor
177 * @param bgid block group id
178 * @return inodes count*/
179 uint32_t ext4_inodes_in_group_cnt(struct ext4_sblock *s, uint32_t bgid);
181 /***************************Read/write/check superblock**********************/
183 /**@brief Superblock write.
184 * @param bdev block device descriptor.
185 * @param s superblock descriptor
186 * @return Standard error code */
187 int ext4_sb_write(struct ext4_blockdev *bdev, struct ext4_sblock *s);
189 /**@brief Superblock read.
190 * @param bdev block device descriptor.
191 * @param s superblock descriptor
192 * @return Standard error code */
193 int ext4_sb_read(struct ext4_blockdev *bdev, struct ext4_sblock *s);
195 /**@brief Superblock simple validation.
196 * @param s superblock descriptor
197 * @return true if OK*/
198 bool ext4_sb_check(struct ext4_sblock *s);
200 /**@brief Superblock presence in block group.
201 * @param s superblock descriptor
202 * @param block_group block group id
203 * @return true if block group has superblock*/
204 bool ext4_sb_is_super_in_bg(struct ext4_sblock *s, uint32_t block_group);
207 bool ext4_sb_sparse(uint32_t 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_ */