NAME

       probe::ioblock.request - Fires whenever making a generic block I/O request.

SYNOPSIS

       ioblock.request

VALUES

       ino
           i-node number of the mapped file

       devname
           block device name

       bdev
           target block device

       vcnt
           bio vector count which represents number of array element (page, offset, length) which make up this
           I/O request

       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

       idx
           offset into the bio vector array

       size
           total size in bytes

       p_start_sect
           points to the start sector of the partition structure of the device

       hw_segments
           number of segments after physical and DMA remapping hardware coalescing is performed

       phys_segments
           number of segments in this bio after physical address coalescing is performed

       bdev_contains
           points to the device object which contains the partition (when bio structure represents a partition)

       rw
           binary trace for read/write request

       sector
           beginning sector for the entire bio

       name
           name of the probe point

       opf
           operations and flags

CONTEXT

       The process makes block I/O request

SEE ALSO

       tapset::ioblock(3stap)

SystemTap Tapset Reference                        November 2019                        PROBE::IOBLOCK.REQ(3stap)