get_max_io

函数名称：Return the maximum number of sectors from the start of a bio that may be* submitted as a single request to a block device. If enough sectors remain,* align the end to the physical block size. Otherwise align the end to the* logical block size

函数原型：static inline unsigned get_max_io_size(struct request_queue *q, struct bio *bio)

返回类型：unsigned

参数：

类型	参数	名称
struct request_queue *	q
struct bio *	bio

146

sectors等于Return maximum size of a request at given offset. Only valid for* file system requests.

147

max_sectors等于sectors

148

pbs等于queue_physical_block_size(q)右移The basic unit of block I/O is a sector. It is used in a number of contexts* in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9* bytes. Variables of type sector_t represent an offset or size that is a* multiple of 512 bytes位

149

lbs等于queue_logical_block_size(q)右移The basic unit of block I/O is a sector. It is used in a number of contexts* in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9* bytes. Variables of type sector_t represent an offset or size that is a* multiple of 512 bytes位

150

start_offset等于 device address in 512 byte sectors 按位与pbs减1

152

max_sectors加等于start_offset

153

max_sectors与等于pbs减1的差的反

154

如果max_sectors大于start_offset则返回:max_sectors减start_offset

157

返回:sectors按位与lbs减1

**调用者**
名称	描述
blk_bio_segment_split	lk_bio_segment_split - split a bio in two bios@q: [in] request queue pointer@bio: [in] bio to be split@bs: [in] bio set to allocate the clone from@segs: [out] number of segments in the bio with the first half of the sectors* Clone @bio, update the

源代码转换工具开放的插件接口	X
支持：c/c++/esqlc/java Oracle/Informix/Mysql 插件可实现：逻辑报告代码生成和批量转换代码

函数逻辑报告