GNU/Linux |
CentOS 5.5 |
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ioblock.request(3stap) |
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ioblock.request − Fires whenever making a generic block I/O request.
ioblock.request
None
devname − block device name ino − i−node number of the mapped file sector − beginning sector for the entire bio 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 vcnt − bio vector count which represents number of array element (page, offset, length) which make up this I/O request idx − offset into the bio vector array phys_segments − number of segments in this bio after physical address coalescing is performed hw_segments − number of segments after physical and DMA remapping hardware coalescing is performed size − total size in bytes bdev − target block device 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
The process makes block I/O request
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ioblock.request(3stap) | ![]() |