timeout()/untimeout() API:
- Clients supply callout handle storage, thus eliminating problems of
resource allocation.
- Insertion and removal of callouts is constant time, important as
this facility is used quite a lot in the kernel.
The old timeout()/untimeout() API has been removed from the kernel.
- split softc size and match/attach out from cfdriver into
a new struct cfattach.
- new "attach" directive for files.*. May specify the name of
the cfattach structure, so that devices may be easily attached
to parents with different autoconfiguration semantics.
[1] check return value from malloc() for NULL before trying to bzero it.
[2] use "=" rather than "|=" when writing to CSR (otherwise you may
ACK something you don't mean to!).
- moved disk_busy() call from xdstrategy() to xdc_startbuf()
[prevents disk_unbusy panic when disk is loaded (if no
free IOPBs, xdstrategy() would queue the buffer for pickup
by xdcintr() but xdcintr() would never call disk_busy().
xdc_startbuf() is a better place since all bufs are routed
through here] problem detected by girish@dworkin.wustl.edu,
diagnosed and corrected by me.
- move disk_unbusy() call in xdc_remove_iorq() before the call to
XDC_FREE() [don't want to access a data structure that was just put
on a free list]
- New metrics handling. Metrics are now kept in the new
`struct disk'. Busy time is now stored as a timeval, and
transfer count in bytes.
- Storage for disklabels is now dynamically allocated, so that
the size of the disk structure is not machine-dependent.
- Several new functions for attaching and detaching disks, and
handling metrics calculation.
Old-style instrumentation is still supported in drivers that did it before.
However, old-style instrumentation is being deprecated, and will go away
once the userland utilities are updated for the new framework.
For usage and architectural details, see the forthcoming disk(9) manual
page.
