- don't use managed mappings/backing objects for wired memory allocations.
save some resources like pv_entry. also fix (most of) PR/27030.
- simplify kernel memory management API.
- simplify pmap bootstrap of some ports.
- some related cleanups.
which bustype should be attached with a specific call to config_found()
(from a "mainbus" or a bus bridge).
Do it for isa/eisa/mca and pci/agp for now. These buses all attach to
an mi interface attribute "isabus", "eisabus" etc., and the autoconf
framework now allows to specify an interface attribute on config_found()
and config_search(), which limits the search of matching config data
to these which attach to that specific attribute.
So we basically have to call config_found_ia(..., "foobus", ...) where
such a bus is attached.
As a consequence, where a "mainbus" or alike also attaches other
devices (eg CPUs) which do not attach to a specific attribute yet,
we need at least pass an attribute name (different from "foobus") so
that the foo bus is not found at these places. This made some minor
changes necessary which are not obviously related to the mentioned buses.
The new code maintains two variables 'current_spl_level' and
'hardware_spl_level'. Variable hardware_spl_level reflects actual
priority level at the hardware's point of view. hardware_spl_level is
always synchronized to hardware.
splraise() just increases current_spl_level. splx() sets
current_spl_level. If (and only if) hardware_spl_level and
current_spl_level is not same, splx() synchronizes interrupt mask
register and hardware_spl_level to current_spl_level.
In most case, splraise() raises current_spl_level and splx() restores
only current_spl_level.
When an interrupt occurs, hardware_spl_level and interrupt mask
register are synchronized to current_spl_level.
In this implementation, during a higher priority interrupt handler is
running, lower priority interrupts never cause intr_dispatch() to run.
It will avoid some race condition.
enabled on amd64). Add a dmat64 field to various PCI attach structures,
and pass it down where needed. Implement a simple new function called
pci_dma64_available(pa) to test if 64bit DMA addresses may be used.
This returns 1 iff _PCI_HAVE_DMA64 is defined in <machine/pci_machdep.h>,
and there is more than 4G of memory.
