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.
isa_dmamap_create() calls to their open/close entrypoints. This worked
with some luck, but broke on i386 when _bus_dmamap_create started
to allocate bounce buffers upfront, since memory below 16M may well
not be available when the sound devices is opened for the Nth time.
To fix this, create a new simple interface, isa_drq_alloc/isa_drq_free,
wrappers around already existing bitmask macros. These are expected
to be used before an isa_dmamap_create call, and after an
isa_dmamap_destroy call, respectively. For the sb and ad1848 drivers,
they're deferred until open/close.
All isa_dmamap_create calls can now use BUS_DMA_ALLOCNOW and be done
at attach time.
page: -1 for error, 0 for EOF, 1 otherwise. Inspired by an OpenBSD commit
message, pointed out by Miod Vallat in private mail.
vax/mba/hp.c: check return value <= 0, not < 0 to be concistent with how
other places handle return values from bounds_check_with_label().
a pointer to current cpu's cpu_info structure. Use cpu_info for
intstk,intr_depth,still_stk,idle_pcb,curpcb,curlwp,etal even on
non-MULTIPROCESSOR machines. Add common macros GET_CPUINFO and
INIT_CPUINFO to get and initialize the cpu_info struct on startup. Make
ibm4xx use the standard <powerpc/frame.h>. Use IFRAME_xx in ibm4xx
trap_subr.S instead of explicit magic offsets. Move INTSTK and SPILLSTK
to std.<platform>. Change faultbuf to a struct instead of an array.
On MPC6XX cpus, stop using the vector page for temporary space and use
reserved space in cpu_info.
cd ${KERNSRCDIR}/${KERNARCHDIR}/compile && ${PRINTOBJDIR}
This is far simpler than the previous system, and more robust with
objdirs built via BSDOBJDIR.
The previous method of finding KERNOBJDIR when using BSDOBJDIR by
referencing _SRC_TOP_OBJ_ from another directory was extremely
fragile due to the depth first tree walk by <bsd.subdir.mk>, and
the caching of _SRC_TOP_OBJ_ (with MAKEOVERRIDES) which would be
empty on the *first* pass to create fresh objdirs.
This change requires adding sys/arch/*/compile/Makefile to create
the objdir in that directory, and descending into arch/*/compile
from arch/*/Makefile. Remove the now-unnecessary .keep_me files
whilst here.
Per lengthy discussion with Andrew Brown.
two ways:
- the child gets its pid as retval[0] (userland stub will turn it into a 0),
retval[1] is 1 and it is 0 in the parent.
- in the child, the fork syscall is successful, hence we must skip the next
instruction.
