shithub: lwext4

ref: d868262d36283441a727e1022414ac706abddb59
dir: /lwext4/ext4_blockdev.h/

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/*
 * Copyright (c) 2013 Grzegorz Kostka ([email protected])
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#ifndef EXT4_BLOCKDEV_H_
#define EXT4_BLOCKDEV_H_

/** @addtogroup lwext4
 * @{
 */
/**
 * @file  ext4_blockdev.h
 * @brief Block device module.
 */

#include <ext4_config.h>
#include <ext4_bcache.h>
#include <ext4_debug.h>


#include <stdbool.h>
#include <stdint.h>

/**@brief	Initialization status flag*/
#define EXT4_BDEV_INITIALIZED			(1 << 0)


/**@brief	Definiton of the simple block device.*/
struct	ext4_blockdev  {

    /**@brief	Open device function
     * @param	bdev block device.*/
    int			(*open)(struct	ext4_blockdev *bdev);

    /**@brief	Block read function.
     * @param	bdev block device
     * @param	buf	output buffer
     * @param	blk_id	block id
     * @param	blk_cnt block count*/
    int			(*bread)(struct	ext4_blockdev *bdev, void *buf,
                uint64_t blk_id, uint32_t blk_cnt);

    /**@brief	Block write function.
     * @param	buf input buffer
     * @param	blk_id block id
     * @param	blk_cnt block count*/
    int			(*bwrite)(struct	ext4_blockdev *bdev, const void *buf,
                uint64_t blk_id, uint32_t blk_cnt);

    /**@brief	Close device function.
     * @param	bdev block device.*/
    int			(*close)(struct	ext4_blockdev *bdev);

    /**@brief	Block size (bytes): physical*/
    uint32_t	ph_bsize;

    /**@brief	Block count: physical.*/
    uint64_t	ph_bcnt;

    /**@brief	Block size buffer: physical.*/
    uint8_t		*ph_bbuf;

    /**@brief	Block size (bytes) logical*/
    uint32_t	lg_bsize;

    /**@brief	Block count: phisical.*/
    uint64_t	lg_bcnt;

    /**@brief	Flags of te block device.*/
    uint8_t		flags;

    /**@brief	Block cache.*/
    struct	ext4_bcache *bc;

    uint8_t		cache_flush_delay;

    uint32_t	bread_ctr;
    uint32_t	bwrite_ctr;
};


/**@brief	Static initialization fo the block device.*/
#define EXT4_BLOCKDEV_STATIC_INSTANCE(__name, __bsize, __bcnt, __open,  \
                                            __bread, __bwrite, __close)	\
        static uint8_t	__name##_ph_bbuf[(__bsize)];                    \
        static struct	ext4_blockdev __name = {                        \
                .open   = __open,                                       \
                .bread  = __bread,                                      \
                .bwrite = __bwrite,                                     \
                .close  = __close,                                      \
                .ph_bsize  = __bsize,                                   \
                .ph_bcnt   = __bcnt,                                    \
                .ph_bbuf   = __name##_ph_bbuf,                          \
        }

/**@brief	Block device initialization.
 * @param	bdev block device descriptor
 * @param	bg_bsize logical block size
 * @param	bdev block device descriptor
 * @return 	standard error code*/
int	ext4_block_init(struct	ext4_blockdev *bdev);


/**@brief	Binds a bcache to block device.
 * @param	bdev block device descriptor
 * @param	bc block cache descriptor
 * @return 	standard error code*/
int ext4_block_bind_bcache(struct ext4_blockdev *bdev,
    struct ext4_bcache *bc);

/**@brief	Close block device
 * @param	bdev block device descriptor
 * @return 	standard error code*/
int ext4_block_fini(struct	ext4_blockdev *bdev);


/**@brief	Set logical block size in block device.
 * @param	bdev block device descriptor
 * @param	lb_size ligical block size (in bytes)
 * @return 	standard error code*/
void ext4_block_set_lb_size(struct	ext4_blockdev *bdev,
    uint64_t lb_bsize);

/**@brief	Block get function (through cache).
 * @param	bdev block device descriptor
 * @param	b block descriptor
 * @param	lba logical block address
 * @return 	standard error code*/
int ext4_block_get(struct	ext4_blockdev *bdev, struct	ext4_block *b,
    uint64_t lba);

/**@brief	Block set procedure (through cache).
 * @param	bdev block device descriptor
 * @param	b block descriptor
 * @return 	standard error code*/
int ext4_block_set(struct	ext4_blockdev *bdev, struct	ext4_block *b);


/**@brief	Block read procedure (without cache)
 * @param	bdev block device descriptor
 * @param	buf output buffer
 * @param	lba logical block adderss
 * @return 	standard error code*/
int ext4_block_get_direct(struct	ext4_blockdev *bdev, void *buf,
    uint64_t lba);


/**@brief	Block write procedure (without cache)
 * @param	bdev block device descriptor
 * @param	buf output buffer
 * @param	lba logical block address
 * @return 	standard error code*/
int ext4_block_set_direct(struct	ext4_blockdev *bdev, const void *buf,
    uint64_t lba);

/**@brief	Write to block device (by direct adress).
 * @param	bdev block device descriptor
 * @param	off byte offset in block device
 * @param	buf input buffer
 * @param	len length of the write nuffer
 * @return 	EOK when sucess*/
int	ext4_block_writebytes(struct	ext4_blockdev *bdev, uint64_t off,
    const void *buf, uint32_t len);



/**@brief	Read freom block device (by direct adress).
 * @param	bdev block device descriptor
 * @param	off byte offset in block device
 * @param	buf input buffer
 * @param	len length of the write nuffer
 * @return 	EOK when sucess*/
int ext4_block_readbytes(struct	ext4_blockdev *bdev, uint64_t off,
    void *buf, uint32_t len);

/**@brief	Enable/disable delayed cache flush mode.
 * @param	bdev block device descriptor
 * @param	on_off
 * 				!0 	- ENABLE
 * 				 0	- DISABLE (all delayed cache buffers will be flushed)
 * @return	standard error code*/
int ext4_block_delay_cache_flush(struct	ext4_blockdev *bdev, uint8_t on_off);

#endif /* EXT4_BLOCKDEV_H_ */

/**
 * @}
 */