get_max_io

Name: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

Proto:static inline unsigned get_max_io_size(struct request_queue *q, struct bio *bio)

Type:unsigned

Parameter:

Type	Parameter	Name
struct request_queue *	q
struct bio *	bio

146

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

147

max_sectors = sectors

148

pbs = queue_physical_block_size(q) >> 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

149

lbs = queue_logical_block_size(q) >> 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

150

start_offset = device address in 512 byte sectors & pbs - 1

152

max_sectors += start_offset

153

max_sectors &= ~(pbs - 1)

154

If max_sectors > start_offset Then Return max_sectors - start_offset

157

Return sectors & lbs - 1

**Caller**
Name	Describe
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

Source code conversion tool public plug-in interface	X
Support c/c++/esqlc/java Oracle/Informix/Mysql Plug-in can realize: logical Report Code generation and batch code conversion

Function report