Add two new arguments to bus_dma_tag_create(): lockfunc and lockfuncarg.
Lockfunc allows a driver to provide a function for managing its locking
semantics while using busdma. At the moment, this is used for the
asynchronous busdma_swi and callback mechanism. Two lockfunc implementations
are provided: busdma_lock_mutex() performs standard mutex operations on the
mutex that is specified from lockfuncarg. dftl_lock() is a panic
implementation and is defaulted to when NULL, NULL are passed to
bus_dma_tag_create(). The only time that NULL, NULL should ever be used is
when the driver ensures that bus_dmamap_load() will not be deferred.
Drivers that do not provide their own locking can pass
busdma_lock_mutex,&Giant args in order to preserve the former behaviour.
sparc64 and powerpc do not provide real busdma_swi functions, so this is
largely a noop on those platforms. The busdma_swi on is64 is not properly
locked yet, so warnings will be emitted on this platform when busdma
callback deferrals happen.
If anyone gets panics or warnings from dflt_lock() being called, please
let me know right away.
Reviewed by: tmm, gibbs
to store an int in the bio->bio_driver1 (a void *). It is big enough,
but you have to match the int sizes first before doing the cast.
Glanced at by: scottl
so can leave stale data in the buffer and confuse the driver.
- enable the ability to set the 'disable' hint for the driver to keep it
from attaching. i.e. 'hw.ips.0.disable=1' will prevent the driver from
attaching.
- Only detach if attach suceeded.
Submitted by: mjacob
series. This driver was generously developed and released by David
Jeffreys and Adaptec. I've updated it to work with 5.x and fixed a
few bugs.
MFC After: 1 week
