ref: 733c5d6645b133b60d304c38fcb1398f94d0618c
dir: /sys/src/cmd/ext4srv/include/ext4_blockdev.h/
#pragma once
#include "ext4_bcache.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, u64int blk_id,
u32int 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,
u64int blk_id, u32int 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*/
u32int ph_bsize;
/**@brief Block count: physical*/
u64int ph_bcnt;
/**@brief Block size buffer: physical*/
u8int *ph_bbuf;
/**@brief Reference counter to block device interface*/
u32int ph_refctr;
/**@brief Physical read counter*/
u32int bread_ctr;
/**@brief Physical write counter*/
u32int 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.*/
u64int part_offset;
/**@brief Part size in bdif. For multi partition mode.*/
u64int part_size;
/**@brief Block cache.*/
struct ext4_bcache *bc;
/**@brief Block size (bytes) logical*/
u32int lg_bsize;
/**@brief Block count: logical*/
u64int lg_bcnt;
/**@brief Cache write back mode reference counter*/
u32int cache_write_back;
/**@brief The filesystem this block device belongs to. */
struct ext4_fs *fs;
void *journal;
};
#pragma incomplete struct ext4_blockdev
/**@brief Static initialization of the block device.*/
#define EXT4_BLOCKDEV_STATIC_INSTANCE(__name, __bsize, __bcnt, __open, __bread,\
__bwrite, __close, __lock, __unlock) \
static u8int __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, u64int 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, u32int 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,
u64int 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,
u64int 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, u64int lba,
u32int 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,
u64int lba, u32int 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, u64int off,
const void *buf, u32int 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, u64int off, void *buf,
u32int 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, u8int on_off);