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29 * Copyright 2009 Develer S.r.l. (http://www.develer.com/)
33 * \author Francesco Sacchi <batt@develer.com>
35 * \brief KBlock interface
41 #include <cfg/compiler.h>
42 #include <cfg/debug.h>
43 #include <cfg/macros.h>
45 /** Type for addressing blocks in the device. */
46 typedef uint32_t block_idx_t;
52 * \name Prototypes for KBlock access functions.
54 * A KBlock user can choose which function subset to implement,
55 * but has to set to NULL unimplemented features.
59 typedef size_t (* kblock_read_direct_t) (struct KBlock *b, block_idx_t index, void *buf, size_t offset, size_t size);
60 typedef int (* kblock_write_block_t) (struct KBlock *b, block_idx_t index, const void *buf);
62 typedef size_t (* kblock_read_t) (struct KBlock *b, void *buf, size_t offset, size_t size);
63 typedef size_t (* kblock_write_t) (struct KBlock *b, const void *buf, size_t offset, size_t size);
64 typedef int (* kblock_load_t) (struct KBlock *b, block_idx_t index);
65 typedef int (* kblock_store_t) (struct KBlock *b, block_idx_t index);
67 typedef int (* kblock_error_t) (struct KBlock *b);
68 typedef int (* kblock_clearerr_t) (struct KBlock *b);
69 typedef int (* kblock_close_t) (struct KBlock *b);
73 * Table of interface functions for a KBlock device.
75 typedef struct KBlockVTable
77 kblock_read_direct_t readDirect;
78 kblock_write_block_t writeBlock;
80 kblock_read_t readBuf;
81 kblock_write_t writeBuf;
85 kblock_error_t error; ///< \sa kblock_error()
86 kblock_clearerr_t clearerr; ///< \sa kblock_clearerr()
88 kblock_close_t close; ///< \sa kblock_close()
92 #define KB_BUFFERED BV(0)
93 #define KB_CACHE_DIRTY BV(1)
96 * KBlock private members.
97 * These are the private members of the KBlock class, please do not
98 * access these directly, use the KBlock API.
100 typedef struct KBlockPriv
102 DB(id_t type); ///< Used to keep track, at runtime, of the class type.
103 int flags; ///< Status and error flags.
105 block_idx_t blk_start; ///< Start block number when the device is trimmed. \sa kblock_trim()
106 block_idx_t curr_blk;
108 const struct KBlockVTable *vt; ///< Virtual table of interface functions.
112 * KBlock: interface for a generic block device.
114 * A block device is a device which can only be read/written
115 * with data blocks of constant size: flash memories,
116 * SD cards, hard disks, etc...
118 * This interface is designed to adapt to most block devices and
119 * use peculiar features in order to save CPU time and memory space.
121 * You do not have to use this structure directly, specific implementations
122 * will be supplied in the peripheral drivers.
124 typedef struct KBlock
126 KBlockPriv priv; ///< Interface private data, do not use directly.
128 /* Public access members */
129 size_t blk_size; ///< Block size.
130 block_idx_t blk_cnt; ///< Number of blocks available in the device.
135 * Use a subset of the blocks on the device.
137 * This function is useful for partitioning a device and use it for
138 * different purposes at the same time.
140 * This function will limit the number of blocks used on the device by setting
141 * a start index and a number of blocks to be used counting from that index.
143 * The blocks outside this range are no more accessible.
145 * Logical block indexes will be mapped to physical indexes inside this new
146 * range automatically. Even following calls to kblock_trim() will use logical
147 * indexes, so, once trimmed, access can only be limited further and never
152 * //...init KBlock device dev
153 * kblock_trim(dev, 200, 1500); // Restrict access to the 200-1700 physical block range.
154 * kblock_load(dev, 0); // Load the physical block #200.
155 * kblock_trim(dev, 0, 300); // Restrict access to the 200-500 physical block range.
158 * \param b KBlock device.
159 * \param start The index of the start block for the limiting window in logical addressing units.
160 * \param count The number of blocks to be used.
163 INLINE void kblock_trim(struct KBlock *b, block_idx_t start, block_idx_t count)
165 ASSERT(start + count <= b->blk_cnt);
166 b->priv.blk_start += start;
171 #define KB_ASSERT_METHOD(b, method) \
175 ASSERT((b)->priv.vt); \
176 ASSERT((b)->priv.vt->method); \
182 * Get the current errors for the device.
184 * \note Calling this function will not clear the errors.
186 * \param b KBlock device.
188 * \return 0 if no error is present, a driver specific mask of errors otherwise.
190 * \sa kblock_clearerr()
192 INLINE int kblock_error(struct KBlock *b)
194 KB_ASSERT_METHOD(b, error);
195 return b->priv.vt->error(b);
199 * Clear the errors of the device.
201 * \param b KBlock device.
203 * \return 0 on success, EOF on errors.
207 INLINE int kblock_clearerr(struct KBlock *b)
209 KB_ASSERT_METHOD(b, clearerr);
210 return b->priv.vt->clearerr(b);
216 * \param b KBlock device.
218 * \return 0 on success, EOF on errors.
220 INLINE int kblock_close(struct KBlock *b)
222 KB_ASSERT_METHOD(b, close);
223 return b->priv.vt->close(b);
226 INLINE bool kblock_cacheDirty(struct KBlock *b)
229 return (b->priv.flags & KB_CACHE_DIRTY);
232 INLINE block_idx_t kblock_cachedBlock(struct KBlock *b)
234 return b->priv.curr_blk;
237 INLINE bool kblock_buffered(struct KBlock *b)
240 return (b->priv.flags & KB_BUFFERED);
243 size_t kblock_read(struct KBlock *b, block_idx_t idx, void *buf, size_t offset, size_t size);
245 size_t kblock_write(struct KBlock *b, block_idx_t idx, const void *buf, size_t offset, size_t size);
247 int kblock_flush(struct KBlock *b);
249 int kblock_copy(struct KBlock *b, block_idx_t idx1, block_idx_t idx2);
251 int kblock_swLoad(struct KBlock *b, block_idx_t index);
252 int kblock_swStore(struct KBlock *b, block_idx_t index);
253 size_t kblock_swReadBuf(struct KBlock *b, void *buf, size_t offset, size_t size);
254 size_t kblock_swWriteBuf(struct KBlock *b, const void *buf, size_t offset, size_t size);
256 #endif /* IO_KBLOCK_H */