Interruption response block
struct irb {
union scsw scsw;
union esw;
__u8 ecw[32];
};
scsw
subchannel status word
esw
extended status word
ecw[32]
extended control word
The irb that is handed to the device driver when an interrupt occurs. For solicited interrupts, the common I/O layer already performs checks whether a field is valid; a field not being valid is always passed as 0. If a unit check occurred, ecw may contain sense data; this is retrieved by the common I/O layer itself if the device doesn't support concurrent sense (so that the device driver never needs to perform basic sene itself). For unsolicited interrupts, the irb is passed as-is (expect for sense data, if applicable).
Cornelia Huck <[email protected]>
Author.