ref: f0f2d452c873255dec4b3359b3f93e349be0f2c5
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);