probe::ioblock.request

probe::ioblock.request
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Name

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

ioblock.request

hw_segments: number of segments after physical and DMA remapping hardware coalescing is performed
bdev_contains: points to the device object which contains the partition (when bio structure represents a partition)
opf: operations and flags
bdev: target block device
phys_segments: number of segments in this bio after physical address coalescing is performed
name: name of the probe point
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
rw: binary trace for read/write request
size: total size in bytes
p_start_sect: points to the start sector of the partition structure of the device
idx: offset into the bio vector array
ino: i-node number of the mapped file
devname: block device name
sector: beginning sector for the entire bio

The process makes block I/O request

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