a heavily stripped down FreeBSD/i386 (brutally stripped down actually) to
attempt to get a stable base to start from. There is a lot missing still.
Worth noting:
- The kernel runs at 1GB in order to cheat with the pmap code. pmap uses
a variation of the PAE code in order to avoid having to worry about 4
levels of page tables yet.
- It boots in 64 bit "long mode" with a tiny trampoline embedded in the
i386 loader. This simplifies locore.s greatly.
- There are still quite a few fragments of i386-specific code that have
not been translated yet, and some that I cheated and wrote dumb C
versions of (bcopy etc).
- It has both int 0x80 for syscalls (but using registers for argument
passing, as is native on the amd64 ABI), and the 'syscall' instruction
for syscalls. int 0x80 preserves all registers, 'syscall' does not.
- I have tried to minimize looking at the NetBSD code, except in a couple
of places (eg: to find which register they use to replace the trashed
%rcx register in the syscall instruction). As a result, there is not a
lot of similarity. I did look at NetBSD a few times while debugging to
get some ideas about what I might have done wrong in my first attempt.
Rename visible x86_64 references to amd64.
Kill MID_MACHINE, its a.out specific, the only platform that supports it
is i386. All of the other platforms should remove it too.
syscall return values should be cleared. The system calls
getcontext() and swapcontext() want to return 0 on success
but these contexts can be switched to at a later time so
the return values need to be cleared in the saved register
sets. Other callers of get_mcontext() would normally want
the context without clearing the return values.
Remove the i386-specific context saving from the KSE code.
get_mcontext() is not i386-specific any more.
Fix a bad pointer in the alpha get_mcontext() code. The
context was being bcopy()'d from &td->tf_frame, but tf_frame
is itself a pointer, so the thread was being copied instead.
Spotted by jake.
Glanced at by: jake
Reviewed by: bde (months ago)
to get actual constant values. This is in preparation for machine/limits.h
retirement.
Discussed on: standards@
Submitted by: Craig Rodrigues <rodrigc@attbi.com> (*)
Modified by: kan
kern_sigprocmask() in the various binary compatibility emulators.
- Replace calls to sigsuspend(), sigaltstack(), sigaction(), and
sigprocmask() that used the stackgap with calls to the corresponding
kern_sig*() functions instead without using the stackgap.
cpu_switch_load_gs, cpu is in context switch, so don't enable interrupt.
because it is in context switch, it is expected sched_lock was held,
so don't PROC_LOCK(p) and psignal, it is LOR, probably we can
set a P_XSIGBUS like flag in p_sflags, and set TDF_ASTPENDING in
td_flags, in ast(), post a SIGBUS to process if P_XSIGBUS was set.
ethernet controller. The driver has been tested with the LinkSys
USB200M adapter. I know for a fact that there are other devices out
there with this chip but don't have all the USB vendor/device IDs.
Note: I'm not sure if this will force the driver to end up in the
install kernel image or not. Special magic needs to be done to exclude
it to keep the boot floppies from bloating again, someone please
advise.
Ignoring maxsegsz may lead to fatal data corruption for some devices.
ex. SBP-2/FireWire
We should apply this change to other platforms except for sparc64.
MFC after: 1 week
enum to an int and redefine the BUS_DMASYNC_* constants as
flags. This allows us to specify several operations in one
call to bus_dmamap_sync() as in NetBSD.
by allprison_mtx), a unique prison/jail identifier field, two path
fields (pr_path for reporting and pr_root vnode instance) to store
the chroot() point of each jail.
o Add jail_attach(2) to allow a process to bind to an existing jail.
o Add change_root() to perform the chroot operation on a specified
vnode.
o Generalize change_dir() to accept a vnode, and move namei() calls
to callers of change_dir().
o Add a new sysctl (security.jail.list) which is a group of
struct xprison instances that represent a snapshot of active jails.
Reviewed by: rwatson, tjr
backend for bus_dmamap_load_mbuf and bus_dmamap_load_uio.
- Increaes MAX_BPAGES to 512. Less than this causes fxp to quickly runs out
of bounce pages.
- Add an argument to reserve_bounce_pages indicating wether this operation
should fail or be queued for later processing if we run out of memory.
The EINPROGRESS return value is not handled properly by consumers of
bus_dmamap_load_mbuf.
- If bounce buffers are required allocate minimum 1 bounce page at map
creation time. If maxsize was small previously this could get truncated
to 0 and the drivers would quickly run out of bounce pages.
- Fix a bug handling the return value of alloc_bounce_pages at map creation
time. It returns the number of pages allocated, not 0 on success.
- Use bus_addr_t for physical addresses to avoid truncation.
- Assert that the map is non-null and not the no bounce map in
add_bounce_pages.
Sponsored by: DARPA, Network Associates Laboratories
the top of the address space to be reclaimed. The problem is that with
the APTD gone the mapable kernel address space runs right to the end of
the 32 bit address space. As a max this is 0x100000000, which can't be
represented in 32 bits, so we have to use ptd entry n-1 and pte offset
n-1, instead of ptd entry n and pte offset 0. There's still 1 page we
can't use, but we gain just under 4 megs of kva (8 megs with PAE).
Sponsored by: DARPA, Network Associates Laboratories
to take care of the KAME IPv6 code which needs ovbcopy() because NetBSD's
bcopy() doesn't handle overlap like ours.
Remove all implementations of ovbcopy().
Previously, bzero was a function pointer on i386, to save a jmp to
bzero_vector. Get rid of this microoptimization as it only confuses
things, adds machine-dependent code to an MD header, and doesn't really
save all that much.
This commit does not add my pagezero() / pagecopy() code.
as it could be and can do with some more cleanup. Currently its under
options LAZY_SWITCH. What this does is avoid %cr3 reloads for short
context switches that do not involve another user process. ie: we can
take an interrupt, switch to a kthread and return to the user without
explicitly flushing the tlb. However, this isn't as exciting as it could
be, the interrupt overhead is still high and too much blocks on Giant
still. There are some debug sysctls, for stats and for an on/off switch.
The main problem with doing this has been "what if the process that you're
running on exits while we're borrowing its address space?" - in this case
we use an IPI to give it a kick when we're about to reclaim the pmap.
Its not compiled in unless you add the LAZY_SWITCH option. I want to fix a
few more things and get some more feedback before turning it on by default.
This is NOT a replacement for Bosko's lazy interrupt stuff. This was more
meant for the kthread case, while his was for interrupts. Mine helps a
little for interrupts, but his helps a lot more.
The stats are enabled with options SWTCH_OPTIM_STATS - this has been a
pseudo-option for years, I just added a bunch of stuff to it.
One non-trivial change was to select a new thread before calling
cpu_switch() in the first place. This allows us to catch the silly
case of doing a cpu_switch() to the current process. This happens
uncomfortably often. This simplifies a bit of the asm code in cpu_switch
(no longer have to call choosethread() in the middle). This has been
implemented on i386 and (thanks to jake) sparc64. The others will come
soon. This is actually seperate to the lazy switch stuff.
Glanced at by: jake, jhb
a pointer that is in user space. It will be used as the basic primitive
for a kernel supported user space lock implementation.
- Implement this function in x86's support.s
- Provide stubs that return -1 in all other architectures. Implementations
will follow along shortly.
Reviewed by: jake
