Keep lguest from being enabled on VISWS or VOYAGER configs, just as is
already done for VMI and XEN. Otherwise randconfigs with VISWS and LGUEST
have this problem:
In file included from arch/x86/kernel/setup_32.c:61:
include/asm-x86/mach-visws/setup_arch.h:8:1: warning: "ARCH_SETUP" redefined
In file included from include/asm/msr.h:80,
from include/asm/processor_32.h:17,
from include/asm/processor.h:2,
from include/asm/thread_info_32.h:16,
from include/asm/thread_info.h:2,
from include/linux/thread_info.h:21,
from include/linux/preempt.h:9,
from include/linux/spinlock.h:49,
from include/linux/seqlock.h:29,
from include/linux/time.h:8,
from include/linux/timex.h:57,
from include/linux/sched.h:53,
from arch/x86/kernel/setup_32.c:24:
include/asm/paravirt.h:458:1: warning: this is the location of the previous definition
(and of course, this happens because kconfig does not follow dependencies
when [evil] select is used...)
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This makes lguest able to use the virtio devices.
We change the device descriptor page from a simple array to a variable
length "type, config_len, status, config data..." format, and
implement virtio_config_ops to read from that config data.
We use the virtio ring implementation for an efficient Guest <-> Host
virtqueue mechanism, and the new LHCALL_NOTIFY hypercall to kick the
host when it changes.
We also use LHCALL_NOTIFY on kernel addresses for very very early
console output. We could have another hypercall, but this hack works
quite well.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
These helper routines supply most of the virtqueue_ops for hypervisors
which want to use a ring for virtio. Unlike the previous lguest
implementation:
1) The rings are variable sized (2^n-1 elements).
2) They have an unfortunate limit of 65535 bytes per sg element.
3) The page numbers are always 64 bit (PAE anyone?)
4) They no longer place used[] on a separate page, just a separate
cacheline.
5) We do a modulo on a variable. We could be tricky if we cared.
6) Interrupts and notifies are suppressed using flags within the rings.
Users need only get the ring pages and provide a notify hook (KVM
wants the guest to allocate the rings, lguest does it sanely).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Dor Laor <dor.laor@qumranet.com>
Lguest has two sides: host support (to launch guests) and guest
support (replacement boot path and paravirt_ops). This moves the
guest side to arch/x86/lguest where it's closer to related code.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
