2 * Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 /** @addtogroup lwext4
32 * @file ext4_blockdev.h
33 * @brief Block device module.
36 #ifndef EXT4_BLOCKDEV_H_
37 #define EXT4_BLOCKDEV_H_
43 #include "ext4_config.h"
44 #include "ext4_bcache.h"
49 struct ext4_blockdev_iface {
50 /**@brief Open device function
51 * @param bdev block device.*/
52 int (*open)(struct ext4_blockdev *bdev);
54 /**@brief Block read function.
55 * @param bdev block device
56 * @param buf output buffer
57 * @param blk_id block id
58 * @param blk_cnt block count*/
59 int (*bread)(struct ext4_blockdev *bdev, void *buf, uint64_t blk_id,
62 /**@brief Block write function.
63 * @param buf input buffer
64 * @param blk_id block id
65 * @param blk_cnt block count*/
66 int (*bwrite)(struct ext4_blockdev *bdev, const void *buf,
67 uint64_t blk_id, uint32_t blk_cnt);
69 /**@brief Close device function.
70 * @param bdev block device.*/
71 int (*close)(struct ext4_blockdev *bdev);
73 /**@brief Lock block device. Required in multi partition mode
74 * operations. Not mandatory field.
75 * @param bdev block device.*/
76 int (*lock)(struct ext4_blockdev *bdev);
78 /**@brief Unlock block device. Required in multi partition mode
79 * operations. Not mandatory field.
80 * @param bdev block device.*/
81 int (*unlock)(struct ext4_blockdev *bdev);
83 /**@brief Block size (bytes): physical*/
86 /**@brief Block count: physical*/
89 /**@brief Block size buffer: physical*/
92 /**@brief Reference counter to block device interface*/
95 /**@brief Physical read counter*/
98 /**@brief Physical write counter*/
102 /**@brief Definition of the simple block device.*/
103 struct ext4_blockdev {
104 /**@brief Block device interface*/
105 struct ext4_blockdev_iface *bdif;
107 /**@brief Offset in bdif. For multi partition mode.*/
108 uint64_t part_offset;
110 /**@brief Part size in bdif. For multi partition mode.*/
113 /**@brief Block cache.*/
114 struct ext4_bcache *bc;
116 /**@brief Block size (bytes) logical*/
119 /**@brief Block count: logical*/
122 /**@brief Cache write back mode reference counter*/
123 uint32_t cache_write_back;
125 /**@brief The filesystem this block device belongs to. */
129 /**@brief Static initialization of the block device.*/
130 #define EXT4_BLOCKDEV_STATIC_INSTANCE(__name, __bsize, __bcnt, __open, __bread,\
131 __bwrite, __close, __lock, __unlock) \
132 static uint8_t __name##_ph_bbuf[(__bsize)]; \
133 static struct ext4_blockdev_iface __name##_iface = { \
136 .bwrite = __bwrite, \
139 .unlock = __unlock, \
140 .ph_bsize = __bsize, \
142 .ph_bbuf = __name##_ph_bbuf, \
144 static struct ext4_blockdev __name = { \
145 .bdif = &__name##_iface, \
147 .part_size = (__bcnt) * (__bsize), \
150 /**@brief Block device initialization.
151 * @param bdev block device descriptor
152 * @param bg_bsize logical block size
153 * @param bdev block device descriptor
154 * @return standard error code*/
155 int ext4_block_init(struct ext4_blockdev *bdev);
157 /**@brief Binds a bcache to block device.
158 * @param bdev block device descriptor
159 * @param bc block cache descriptor
160 * @return standard error code*/
161 int ext4_block_bind_bcache(struct ext4_blockdev *bdev, struct ext4_bcache *bc);
163 /**@brief Close block device
164 * @param bdev block device descriptor
165 * @return standard error code*/
166 int ext4_block_fini(struct ext4_blockdev *bdev);
168 /**@brief Flush data in given buffer to disk.
169 * @param bdev block device descriptor
171 * @return standard error code*/
172 int ext4_block_flush_buf(struct ext4_blockdev *bdev, struct ext4_buf *buf);
174 /**@brief Flush data in buffer of given lba to disk,
175 * if that buffer exists in block cache.
176 * @param bdev block device descriptor
177 * @param lba logical block address
178 * @return standard error code*/
179 int ext4_block_flush_lba(struct ext4_blockdev *bdev, uint64_t lba);
181 /**@brief Set logical block size in block device.
182 * @param bdev block device descriptor
183 * @param lb_size logical block size (in bytes)
184 * @return standard error code*/
185 void ext4_block_set_lb_size(struct ext4_blockdev *bdev, uint32_t lb_bsize);
187 /**@brief Block get function (through cache, don't read).
188 * @param bdev block device descriptor
189 * @param b block descriptor
190 * @param lba logical block address
191 * @return standard error code*/
192 int ext4_block_get_noread(struct ext4_blockdev *bdev, struct ext4_block *b,
195 /**@brief Block get function (through cache).
196 * @param bdev block device descriptor
197 * @param b block descriptor
198 * @param lba logical block address
199 * @return standard error code*/
200 int ext4_block_get(struct ext4_blockdev *bdev, struct ext4_block *b,
203 /**@brief Block set procedure (through cache).
204 * @param bdev block device descriptor
205 * @param b block descriptor
206 * @return standard error code*/
207 int ext4_block_set(struct ext4_blockdev *bdev, struct ext4_block *b);
209 /**@brief Block read procedure (without cache)
210 * @param bdev block device descriptor
211 * @param buf output buffer
212 * @param lba logical block address
213 * @return standard error code*/
214 int ext4_blocks_get_direct(struct ext4_blockdev *bdev, void *buf, uint64_t lba,
217 /**@brief Block write procedure (without cache)
218 * @param bdev block device descriptor
219 * @param buf output buffer
220 * @param lba logical block address
221 * @return standard error code*/
222 int ext4_blocks_set_direct(struct ext4_blockdev *bdev, const void *buf,
223 uint64_t lba, uint32_t cnt);
225 /**@brief Write to block device (by direct address).
226 * @param bdev block device descriptor
227 * @param off byte offset in block device
228 * @param buf input buffer
229 * @param len length of the write buffer
230 * @return standard error code*/
231 int ext4_block_writebytes(struct ext4_blockdev *bdev, uint64_t off,
232 const void *buf, uint32_t len);
234 /**@brief Read freom block device (by direct address).
235 * @param bdev block device descriptor
236 * @param off byte offset in block device
237 * @param buf input buffer
238 * @param len length of the write buffer
239 * @return standard error code*/
240 int ext4_block_readbytes(struct ext4_blockdev *bdev, uint64_t off, void *buf,
243 /**@brief Flush all dirty buffers to disk
244 * @param bdev block device descriptor
245 * @return standard error code*/
246 int ext4_block_cache_flush(struct ext4_blockdev *bdev);
248 /**@brief Enable/disable write back cache mode
249 * @param bdev block device descriptor
252 * 0 - DISABLE (all delayed cache buffers will be flushed)
253 * @return standard error code*/
254 int ext4_block_cache_write_back(struct ext4_blockdev *bdev, uint8_t on_off);
260 #endif /* EXT4_BLOCKDEV_H_ */