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 More complex filesystem functions.
41 #ifndef EXT4_EXTENT_H_
42 #define EXT4_EXTENT_H_
48 #include "ext4_config.h"
49 #include "ext4_types.h"
50 #include "ext4_inode.h"
54 * Array of ext4_ext_path contains path to some extent.
55 * Creation/lookup routines use it for traversal/splitting/etc.
56 * Truncate uses it to simulate recursive walking.
58 struct ext4_extent_path {
60 struct ext4_block block;
63 struct ext4_extent_header *header;
64 struct ext4_extent_index *index;
65 struct ext4_extent *extent;
70 /**@brief Get logical number of the block covered by extent.
71 * @param extent Extent to load number from
72 * @return Logical number of the first block covered by extent */
73 static inline uint32_t ext4_extent_get_first_block(struct ext4_extent *extent)
75 return to_le32(extent->first_block);
78 /**@brief Set logical number of the first block covered by extent.
79 * @param extent Extent to set number to
80 * @param iblock Logical number of the first block covered by extent */
81 static inline void ext4_extent_set_first_block(struct ext4_extent *extent,
84 extent->first_block = to_le32(iblock);
87 /**@brief Get number of blocks covered by extent.
88 * @param extent Extent to load count from
89 * @return Number of blocks covered by extent */
90 static inline uint16_t ext4_extent_get_block_count(struct ext4_extent *extent)
92 if (EXT4_EXT_IS_UNWRITTEN(extent))
93 return EXT4_EXT_GET_LEN_UNWRITTEN(extent);
95 return EXT4_EXT_GET_LEN(extent);
97 /**@brief Set number of blocks covered by extent.
98 * @param extent Extent to load count from
99 * @param count Number of blocks covered by extent
100 * @param unwritten Whether the extent is unwritten or not */
101 static inline void ext4_extent_set_block_count(struct ext4_extent *extent,
102 uint16_t count, bool unwritten)
104 EXT4_EXT_SET_LEN(extent, count);
106 EXT4_EXT_SET_UNWRITTEN(extent);
109 /**@brief Get physical number of the first block covered by extent.
110 * @param extent Extent to load number
111 * @return Physical number of the first block covered by extent */
112 static inline uint64_t ext4_extent_get_start(struct ext4_extent *extent)
114 return ((uint64_t)to_le16(extent->start_hi)) << 32 |
115 ((uint64_t)to_le32(extent->start_lo));
119 /**@brief Set physical number of the first block covered by extent.
120 * @param extent Extent to load number
121 * @param fblock Physical number of the first block covered by extent */
122 static inline void ext4_extent_set_start(struct ext4_extent *extent, uint64_t fblock)
124 extent->start_lo = to_le32((fblock << 32) >> 32);
125 extent->start_hi = to_le16((uint16_t)(fblock >> 32));
129 /**@brief Get logical number of the block covered by extent index.
130 * @param index Extent index to load number from
131 * @return Logical number of the first block covered by extent index */
132 static inline uint32_t
133 ext4_extent_index_get_first_block(struct ext4_extent_index *index)
135 return to_le32(index->first_block);
138 /**@brief Set logical number of the block covered by extent index.
139 * @param index Extent index to set number to
140 * @param iblock Logical number of the first block covered by extent index */
142 ext4_extent_index_set_first_block(struct ext4_extent_index *index,
145 index->first_block = to_le32(iblock);
148 /**@brief Get physical number of block where the child node is located.
149 * @param index Extent index to load number from
150 * @return Physical number of the block with child node */
151 static inline uint64_t
152 ext4_extent_index_get_leaf(struct ext4_extent_index *index)
154 return ((uint64_t)to_le16(index->leaf_hi)) << 32 |
155 ((uint64_t)to_le32(index->leaf_lo));
158 /**@brief Set physical number of block where the child node is located.
159 * @param index Extent index to set number to
160 * @param fblock Ohysical number of the block with child node */
161 static inline void ext4_extent_index_set_leaf(struct ext4_extent_index *index,
164 index->leaf_lo = to_le32((fblock << 32) >> 32);
165 index->leaf_hi = to_le16((uint16_t)(fblock >> 32));
168 /**@brief Get magic value from extent header.
169 * @param header Extent header to load value from
170 * @return Magic value of extent header */
171 static inline uint16_t
172 ext4_extent_header_get_magic(struct ext4_extent_header *header)
174 return to_le16(header->magic);
177 /**@brief Set magic value to extent header.
178 * @param header Extent header to set value to
179 * @param magic Magic value of extent header */
180 static inline void ext4_extent_header_set_magic(struct ext4_extent_header *header,
183 header->magic = to_le16(magic);
186 /**@brief Get number of entries from extent header
187 * @param header Extent header to get value from
188 * @return Number of entries covered by extent header */
189 static inline uint16_t
190 ext4_extent_header_get_entries_count(struct ext4_extent_header *header)
192 return to_le16(header->entries_count);
195 /**@brief Set number of entries to extent header
196 * @param header Extent header to set value to
197 * @param count Number of entries covered by extent header */
199 ext4_extent_header_set_entries_count(struct ext4_extent_header *header,
202 header->entries_count = to_le16(count);
205 /**@brief Get maximum number of entries from extent header
206 * @param header Extent header to get value from
207 * @return Maximum number of entries covered by extent header */
208 static inline uint16_t
209 ext4_extent_header_get_max_entries_count(struct ext4_extent_header *header)
211 return to_le16(header->max_entries_count);
214 /**@brief Set maximum number of entries to extent header
215 * @param header Extent header to set value to
216 * @param max_count Maximum number of entries covered by extent header */
218 ext4_extent_header_set_max_entries_count(struct ext4_extent_header *header,
221 header->max_entries_count = to_le16(max_count);
224 /**@brief Get depth of extent subtree.
225 * @param header Extent header to get value from
226 * @return Depth of extent subtree */
227 static inline uint16_t
228 ext4_extent_header_get_depth(struct ext4_extent_header *header)
230 return to_le16(header->depth);
233 /**@brief Set depth of extent subtree.
234 * @param header Extent header to set value to
235 * @param depth Depth of extent subtree */
237 ext4_extent_header_set_depth(struct ext4_extent_header *header, uint16_t depth)
239 header->depth = to_le16(depth);
242 /**@brief Get generation from extent header
243 * @param header Extent header to get value from
244 * @return Generation */
245 static inline uint32_t
246 ext4_extent_header_get_generation(struct ext4_extent_header *header)
248 return to_le32(header->generation);
251 /**@brief Set generation to extent header
252 * @param header Extent header to set value to
253 * @param generation Generation */
255 ext4_extent_header_set_generation(struct ext4_extent_header *header,
258 header->generation = to_le32(generation);
261 /******************************************************************************/
264 static inline void ext4_extent_tree_init(struct ext4_inode_ref *inode_ref)
266 /* Initialize extent root header */
267 struct ext4_extent_header *header =
268 ext4_inode_get_extent_header(inode_ref->inode);
269 ext4_extent_header_set_depth(header, 0);
270 ext4_extent_header_set_entries_count(header, 0);
271 ext4_extent_header_set_generation(header, 0);
272 ext4_extent_header_set_magic(header, EXT4_EXTENT_MAGIC);
274 uint16_t max_entries = (EXT4_INODE_BLOCKS * sizeof(uint32_t) -
275 sizeof(struct ext4_extent_header)) /
276 sizeof(struct ext4_extent);
278 ext4_extent_header_set_max_entries_count(header, max_entries);
279 inode_ref->dirty = true;
285 int ext4_extent_get_blocks(struct ext4_inode_ref *inode_ref, ext4_lblk_t iblock,
286 uint32_t max_blocks, ext4_fsblk_t *result, bool create,
287 uint32_t *blocks_count);
290 /**@brief Release all data blocks starting from specified logical block.
291 * @param inode_ref I-node to release blocks from
292 * @param iblock_from First logical block to release
293 * @return Error code */
294 int ext4_extent_remove_space(struct ext4_inode_ref *inode_ref, ext4_lblk_t from,
302 #endif /* EXT4_EXTENT_H_ */