1/*
2 * Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
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.
16 *
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.
27 */
28/** @addtogroup lwext4
29 * @{
30 */
31/**
32 * @file ext4_blockdev.h
33 * @brief Block device module.
34 */
35
36#ifndef EXT4_BLOCKDEV_H_
37#define EXT4_BLOCKDEV_H_
38
39#ifdef __cplusplus
40extern "C" {
41#endif
42
43#include <ext4_config.h>
44#include <ext4_bcache.h>
45
46#include <stdbool.h>
47#include <stdint.h>
48
49struct ext4_blockdev_iface {
50 /**@brief Open device function
51 * @param bdev block device.*/
52 int (*open)(struct ext4_blockdev *bdev);
53
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,
60 uint32_t blk_cnt);
61
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);
68
69 /**@brief Close device function.
70 * @param bdev block device.*/
71 int (*close)(struct ext4_blockdev *bdev);
72
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);
77
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);
82
83 /**@brief Block size (bytes): physical*/
84 uint32_t ph_bsize;
85
86 /**@brief Block count: physical*/
87 uint64_t ph_bcnt;
88
89 /**@brief Block size buffer: physical*/
90 uint8_t *ph_bbuf;
91
92 /**@brief Reference counter to block device interface*/
93 uint32_t ph_refctr;
94
95 /**@brief Physical read counter*/
96 uint32_t bread_ctr;
97
98 /**@brief Physical write counter*/
99 uint32_t bwrite_ctr;
100
101 /**@brief User data pointer*/
102 void* p_user;
103};
104
105/**@brief Definition of the simple block device.*/
106struct ext4_blockdev {
107 /**@brief Block device interface*/
108 struct ext4_blockdev_iface *bdif;
109
110 /**@brief Offset in bdif. For multi partition mode.*/
111 uint64_t part_offset;
112
113 /**@brief Part size in bdif. For multi partition mode.*/
114 uint64_t part_size;
115
116 /**@brief Block cache.*/
117 struct ext4_bcache *bc;
118
119 /**@brief Block size (bytes) logical*/
120 uint32_t lg_bsize;
121
122 /**@brief Block count: logical*/
123 uint64_t lg_bcnt;
124
125 /**@brief Cache write back mode reference counter*/
126 uint32_t cache_write_back;
127
128 /**@brief The filesystem this block device belongs to. */
129 struct ext4_fs *fs;
130
131 void *journal;
132};
133
134/**@brief Static initialization of the block device.*/
135#define EXT4_BLOCKDEV_STATIC_INSTANCE(__name, __bsize, __bcnt, __open, __bread,\
136 __bwrite, __close, __lock, __unlock) \
137 static uint8_t __name##_ph_bbuf[(__bsize)]; \
138 static struct ext4_blockdev_iface __name##_iface = { \
139 .open = __open, \
140 .bread = __bread, \
141 .bwrite = __bwrite, \
142 .close = __close, \
143 .lock = __lock, \
144 .unlock = __unlock, \
145 .ph_bsize = __bsize, \
146 .ph_bcnt = __bcnt, \
147 .ph_bbuf = __name##_ph_bbuf, \
148 }; \
149 static struct ext4_blockdev __name = { \
150 .bdif = &__name##_iface, \
151 .part_offset = 0, \
152 .part_size = (__bcnt) * (__bsize), \
153 }
154
155/**@brief Block device initialization.
156 * @param bdev block device descriptor
157 * @return standard error code*/
158int ext4_block_init(struct ext4_blockdev *bdev);
159
160/**@brief Binds a bcache to block device.
161 * @param bdev block device descriptor
162 * @param bc block cache descriptor
163 * @return standard error code*/
164int ext4_block_bind_bcache(struct ext4_blockdev *bdev, struct ext4_bcache *bc);
165
166/**@brief Close block device
167 * @param bdev block device descriptor
168 * @return standard error code*/
169int ext4_block_fini(struct ext4_blockdev *bdev);
170
171/**@brief Flush data in given buffer to disk.
172 * @param bdev block device descriptor
173 * @param buf buffer
174 * @return standard error code*/
175int ext4_block_flush_buf(struct ext4_blockdev *bdev, struct ext4_buf *buf);
176
177/**@brief Flush data in buffer of given lba to disk,
178 * if that buffer exists in block cache.
179 * @param bdev block device descriptor
180 * @param lba logical block address
181 * @return standard error code*/
182int ext4_block_flush_lba(struct ext4_blockdev *bdev, uint64_t lba);
183
184/**@brief Set logical block size in block device.
185 * @param bdev block device descriptor
186 * @param lb_bsize logical block size (in bytes)*/
187void ext4_block_set_lb_size(struct ext4_blockdev *bdev, uint32_t lb_bsize);
188
189/**@brief Block get function (through cache, don't read).
190 * @param bdev block device descriptor
191 * @param b block descriptor
192 * @param lba logical block address
193 * @return standard error code*/
194int ext4_block_get_noread(struct ext4_blockdev *bdev, struct ext4_block *b,
195 uint64_t lba);
196
197/**@brief Block get function (through cache).
198 * @param bdev block device descriptor
199 * @param b block descriptor
200 * @param lba logical block address
201 * @return standard error code*/
202int ext4_block_get(struct ext4_blockdev *bdev, struct ext4_block *b,
203 uint64_t lba);
204
205/**@brief Block set procedure (through cache).
206 * @param bdev block device descriptor
207 * @param b block descriptor
208 * @return standard error code*/
209int ext4_block_set(struct ext4_blockdev *bdev, struct ext4_block *b);
210
211/**@brief Block read procedure (without cache)
212 * @param bdev block device descriptor
213 * @param buf output buffer
214 * @param lba logical block address
215 * @return standard error code*/
216int ext4_blocks_get_direct(struct ext4_blockdev *bdev, void *buf, uint64_t lba,
217 uint32_t cnt);
218
219/**@brief Block write procedure (without cache)
220 * @param bdev block device descriptor
221 * @param buf output buffer
222 * @param lba logical block address
223 * @return standard error code*/
224int ext4_blocks_set_direct(struct ext4_blockdev *bdev, const void *buf,
225 uint64_t lba, uint32_t cnt);
226
227/**@brief Write to block device (by direct address).
228 * @param bdev block device descriptor
229 * @param off byte offset in block device
230 * @param buf input buffer
231 * @param len length of the write buffer
232 * @return standard error code*/
233int ext4_block_writebytes(struct ext4_blockdev *bdev, uint64_t off,
234 const void *buf, uint32_t len);
235
236/**@brief Read freom block device (by direct address).
237 * @param bdev block device descriptor
238 * @param off byte offset in block device
239 * @param buf input buffer
240 * @param len length of the write buffer
241 * @return standard error code*/
242int ext4_block_readbytes(struct ext4_blockdev *bdev, uint64_t off, void *buf,
243 uint32_t len);
244
245/**@brief Flush all dirty buffers to disk
246 * @param bdev block device descriptor
247 * @return standard error code*/
248int ext4_block_cache_flush(struct ext4_blockdev *bdev);
249
250/**@brief Enable/disable write back cache mode
251 * @param bdev block device descriptor
252 * @param on_off
253 * !0 - ENABLE
254 * 0 - DISABLE (all delayed cache buffers will be flushed)
255 * @return standard error code*/
256int ext4_block_cache_write_back(struct ext4_blockdev *bdev, uint8_t on_off);
257
258#ifdef __cplusplus
259}
260#endif
261
262#endif /* EXT4_BLOCKDEV_H_ */
263
264/**
265 * @}
266 */
267