to select the maximum segment size for each bus_dmamap_load (up to the maxsegsz
supplied to bus_dmamap_create). dm_maxsegsz is reset to the value supplied to
bus_dmamap_create when the dmamap is unloaded.
process context ('reaper').
From within the exiting process context:
* deactivate pmap and free vmspace while we can still block
* introduce MD cpu_lwp_free() - this cleans all MD-specific context (such
as FPU state), and is the last potentially blocking operation;
all of cpu_wait(), and most of cpu_exit(), is now folded into cpu_lwp_free()
* process is now immediatelly marked as zombie and made available for pickup
by parent; the remaining last lwp continues the exit as fully detached
* MI (rather than MD) code bumps uvmexp.swtch, cpu_exit() is now same
for both 'process' and 'lwp' exit
uvm_lwp_exit() is modified to never block; the u-area memory is now
always just linked to the list of available u-areas. Introduce (blocking)
uvm_uarea_drain(), which is called to release the excessive u-area memory;
this is called by parent within wait4(), or by pagedaemon on memory shortage.
uvm_uarea_free() is now private function within uvm_glue.c.
MD process/lwp exit code now always calls lwp_exit2() immediatelly after
switching away from the exiting lwp.
g/c now unneeded routines and variables, including the reaper kernel thread
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.
clean up some other stuff along the way, including:
- use m68k/cacheops.*, remove duplicates from cpu.h.
- centralize a few declarations in (all the copies of) cpu.h.
- define M68K_VAC on platforms which have a VAC.
- switch the sun platforms to the (now common) proc_trampoline().
- do the phys_map thang on the sun platforms too, no reason not to.
of machine-specific headers. When ${MACHINE} is sun2, this
allows building the sun3 and sun3x parts of libsa, which need
things like <machine/param3.h> and <machine/param3x.h> to be
#includeable.
drochner