Documentation made easier
probe::ioblock_trace.request − Fires just as a generic block I/O request is created for a bio.
ioblock_trace.request
q
request queue on which this bio was queued.
vcnt
bio vector count which represents number of array element (page, offset, length) which make up this I/O request
size
total size in bytes
devname
block device name
name
name of the probe point
bdev
target block device
flags
see below BIO_UPTODATE 0 ok after I/O completion BIO_RW_BLOCK 1 RW_AHEAD set, and read/write would block BIO_EOF 2 out−out−bounds error BIO_SEG_VALID 3 nr_hw_seg valid BIO_CLONED 4 doesn't own data BIO_BOUNCED 5 bio is a bounce bio BIO_USER_MAPPED 6 contains user pages BIO_EOPNOTSUPP 7 not supported
opf
operations and flags
ino
i−node number of the mapped file
bytes_done
number of bytes transferred
sector
beginning sector for the entire bio
bdev_contains
points to the device object which contains the partition (when bio structure represents a partition)
p_start_sect
points to the start sector of the partition structure of the device
rw
binary trace for read/write request
idx
offset into the bio vector array phys_segments − number of segments in this bio after physical address coalescing is performed.
The process makes block I/O request
tapset::ioblock(3stap)