ref: b220675fe53ccc0077952a145ba8d96f93d5fe7f
dir: /include/ext4_blockdev.h/
/*
* Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
* 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.
*/
/** @addtogroup lwext4
* @{
*/
/**
* @file ext4_blockdev.h
* @brief Block device module.
*/
#ifndef EXT4_BLOCKDEV_H_
#define EXT4_BLOCKDEV_H_
#ifdef __cplusplus
extern "C" {
#endif
#include <ext4_config.h>
#include <ext4_bcache.h>
#include <stdbool.h>
#include <stdint.h>
struct ext4_blockdev_iface {
/**@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 Lock block device. Required in multi partition mode
* operations. Not mandatory field.
* @param bdev block device.*/
int (*lock)(struct ext4_blockdev *bdev);
/**@brief Unlock block device. Required in multi partition mode
* operations. Not mandatory field.
* @param bdev block device.*/
int (*unlock)(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 Reference counter to block device interface*/
uint32_t ph_refctr;
/**@brief Physical read counter*/
uint32_t bread_ctr;
/**@brief Physical write counter*/
uint32_t bwrite_ctr;
/**@brief User data pointer*/
void* p_user;
};
/**@brief Definition of the simple block device.*/
struct ext4_blockdev {
/**@brief Block device interface*/
struct ext4_blockdev_iface *bdif;
/**@brief Offset in bdif. For multi partition mode.*/
uint64_t part_offset;
/**@brief Part size in bdif. For multi partition mode.*/
uint64_t part_size;
/**@brief Block cache.*/
struct ext4_bcache *bc;
/**@brief Block size (bytes) logical*/
uint32_t lg_bsize;
/**@brief Block count: logical*/
uint64_t lg_bcnt;
/**@brief Cache write back mode reference counter*/
uint32_t cache_write_back;
/**@brief The filesystem this block device belongs to. */
struct ext4_fs *fs;
void *journal;
};
#ifdef __plan9__
#pragma incomplete struct ext4_blockdev
#endif
/**@brief Static initialization of the block device.*/
#define EXT4_BLOCKDEV_STATIC_INSTANCE(__name, __bsize, __bcnt, __open, __bread,\
__bwrite, __close, __lock, __unlock) \
static uint8_t __name##_ph_bbuf[(__bsize)]; \
static struct ext4_blockdev_iface __name##_iface = { \
.open = __open, \
.bread = __bread, \
.bwrite = __bwrite, \
.close = __close, \
.lock = __lock, \
.unlock = __unlock, \
.ph_bsize = __bsize, \
.ph_bcnt = __bcnt, \
.ph_bbuf = __name##_ph_bbuf, \
}; \
static struct ext4_blockdev __name = { \
.bdif = &__name##_iface, \
.part_offset = 0, \
.part_size = (__bcnt) * (__bsize), \
}
/**@brief Block device initialization.
* @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 Flush data in given buffer to disk.
* @param bdev block device descriptor
* @param buf buffer
* @return standard error code*/
int ext4_block_flush_buf(struct ext4_blockdev *bdev, struct ext4_buf *buf);
/**@brief Flush data in buffer of given lba to disk,
* if that buffer exists in block cache.
* @param bdev block device descriptor
* @param lba logical block address
* @return standard error code*/
int ext4_block_flush_lba(struct ext4_blockdev *bdev, uint64_t lba);
/**@brief Set logical block size in block device.
* @param bdev block device descriptor
* @param lb_size logical block size (in bytes)
* @return standard error code*/
void ext4_block_set_lb_size(struct ext4_blockdev *bdev, uint32_t lb_bsize);
/**@brief Block get function (through cache, don't read).
* @param bdev block device descriptor
* @param b block descriptor
* @param lba logical block address
* @return standard error code*/
int ext4_block_get_noread(struct ext4_blockdev *bdev, struct ext4_block *b,
uint64_t lba);
/**@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 address
* @return standard error code*/
int ext4_blocks_get_direct(struct ext4_blockdev *bdev, void *buf, uint64_t lba,
uint32_t cnt);
/**@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_blocks_set_direct(struct ext4_blockdev *bdev, const void *buf,
uint64_t lba, uint32_t cnt);
/**@brief Write to block device (by direct address).
* @param bdev block device descriptor
* @param off byte offset in block device
* @param buf input buffer
* @param len length of the write buffer
* @return standard error code*/
int ext4_block_writebytes(struct ext4_blockdev *bdev, uint64_t off,
const void *buf, uint32_t len);
/**@brief Read freom block device (by direct address).
* @param bdev block device descriptor
* @param off byte offset in block device
* @param buf input buffer
* @param len length of the write buffer
* @return standard error code*/
int ext4_block_readbytes(struct ext4_blockdev *bdev, uint64_t off, void *buf,
uint32_t len);
/**@brief Flush all dirty buffers to disk
* @param bdev block device descriptor
* @return standard error code*/
int ext4_block_cache_flush(struct ext4_blockdev *bdev);
/**@brief Enable/disable write back cache 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_cache_write_back(struct ext4_blockdev *bdev, uint8_t on_off);
#ifdef __cplusplus
}
#endif
#endif /* EXT4_BLOCKDEV_H_ */
/**
* @}
*/