Commit Graph

4 Commits

Author SHA1 Message Date
Randy Dunlap b8415ec34f lguest: prevent VISWS or VOYAGER randconfigs
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>
2007-11-29 09:24:55 -08:00
Rusty Russell 19f1537b7b Lguest support for Virtio
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>
2007-10-23 15:49:56 +10:00
Rusty Russell 0a8a69dd77 Virtio helper routines for a descriptor ringbuffer implementation
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>
2007-10-23 15:49:55 +10:00
Rusty Russell 34b8867a03 Move lguest guest support to arch/x86.
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>
2007-10-23 15:49:50 +10:00