This allows guest memory to be swapped.  Pages which are currently mapped
via shadow page tables are pinned into memory, but all other pages can
be freely swapped.

The patch makes gfn_to_page() elevate the page's reference count, and
introduces kvm_release_page() that pairs with it.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

In case the page is not present in the guest memory map, return a dummy
page the guest can scribble on.

This simplifies error checking in its users.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

The current kvm mmu only reverse maps writable translation.  This is used
to write-protect a page in case it becomes a pagetable.

But with swapping support, we need a reverse mapping of read-only pages as
well:  when we evict a page, we need to remove any mapping to it, whether
writable or not.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Instruction: cmc, clc, cli, sti
opcodes: 0xf5, 0xf8, 0xfa, 0xfb respectively.

[avi: fix reference to EFLG_IF which is not defined anywhere]
Signed-off-by: Nitin A Kamble <nitin.a.kamble@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Simplify the walker level loop not to carry so much information from one
loop to the next.  In addition to being complex, this made kmap_atomic()
critical sections difficult to manage.

As a result of this change, kmap_atomic() sections are limited to actually
touching the guest pte, which allows the other functions called from the
walker to do sleepy operations.  This will happen when we enable swapping.
Signed-off-by: Avi Kivity <avi@qumranet.com>

Instructions:
	inc r16/r32 (opcode 0x40-0x47)
	dec r16/r32 (opcode 0x48-0x4f)
Signed-off-by: Nitin A Kamble <nitin.a.kamble@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

We now have a new namespace, KVM_REQ_*, for bits in vcpu->requests.
Signed-off-by: Avi Kivity <avi@qumranet.com>

Beside the obvious goodness of making code more common, this prevents
a livelock with the next patch which moves interrupt injection out of the
critical section.
Signed-off-by: Avi Kivity <avi@qumranet.com>

Add new-line at end of debug strings.
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>

If no apic is enabled in the bitmap of an interrupt delivery with delivery
mode of lowest priority, a warning should be reported rather than select
a fallback vcpu
Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Eddie (Yaozu) Dong <eddie.dong@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

This patch splits kvm_vcpu_ioctl into archtecture independent parts, and
x86 specific parts which go to kvm_arch_vcpu_ioctl in x86.c.

Common ioctls for all architectures are:
KVM_RUN, KVM_GET/SET_(S-)REGS, KVM_TRANSLATE, KVM_INTERRUPT,
KVM_DEBUG_GUEST, KVM_SET_SIGNAL_MASK, KVM_GET/SET_FPU
Note that some PPC chips don't have an FPU, so we might need an #ifdef
around KVM_GET/SET_FPU one day.

x86 specific ioctls are:
KVM_GET/SET_LAPIC, KVM_SET_CPUID, KVM_GET/SET_MSRS

An interresting aspect is vcpu_load/vcpu_put. We now have a common
vcpu_load/put which does the preemption stuff, and an architecture
specific kvm_arch_vcpu_load/put. In the x86 case, this one calls the
vmx/svm function defined in kvm_x86_ops.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Since the mmu uses different shadow pages for dirty large pages and clean
large pages, this allows the mmu to drop ptes that are now invalid.
Signed-off-by: Avi Kivity <avi@qumranet.com>

Signed-off-by: Avi Kivity <avi@qumranet.com>

This is consistent with real-mode permissions.
Signed-off-by: Avi Kivity <avi@qumranet.com>

By forcing clean huge pages to be read-only, we have separate roles
for the shadow of a clean large page and the shadow of a dirty large
page.  This is necessary because different ptes will be instantiated
for the two cases, even for read faults.
Signed-off-by: Avi Kivity <avi@qumranet.com>

We must set the bit before the shift, otherwise the wrong bit gets set.
Signed-off-by: Avi Kivity <avi@qumranet.com>

This is more consistent with the accessed bit management, and makes the dirty
bit available earlier for other purposes.
Signed-off-by: Avi Kivity <avi@qumranet.com>

This time, the biggest change is gpa_to_hpa. The translation of GPA to HPA does
not depend on the VCPU state unlike GVA to GPA so there's no need to pass in
the kvm_vcpu.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Some of the MMU functions take a struct kvm_vcpu even though they affect all
VCPUs.  This patch cleans up some of them to instead take a struct kvm.  This
makes things a bit more clear.

The main thing that was confusing me was whether certain functions need to be
called on all VCPUs.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Instead of having the kernel allocate memory to the guest, let userspace
allocate it and pass the address to the kernel.

This is required for s390 support, but also enables features like memory
sharing and using hugetlbfs backed memory.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Signed-off-by: Mike D. Day <ncmike@ncultra.org>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Since vcpu->apic is of the correct type, there's not need to cast.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Move kvm_create_lapic() into kvm_vcpu_init(), rather than having svm
and vmx do it.  And make it return the error rather than a fairly
random -ENOMEM.

This also solves the problem that neither svm.c nor vmx.c actually
handles the error path properly.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Instead of the asymetry of kvm_free_apic, implement kvm_free_lapic().
And guess what?  I found a minor bug: we don't need to hrtimer_cancel()
from kvm_main.c, because we do that in kvm_free_apic().

Also:
1) kvm_vcpu_uninit should be the reverse order from kvm_vcpu_init.
2) Don't set apic->regs_page to zero before freeing apic.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Avi Kivity <avi@qumranet.com>

The user is now able to set how many mmu pages will be allocated to the guest.
Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

When kvm uses user-allocated pages in the future for the guest, we won't
be able to use page->private for rmap, since page->rmap is reserved for
the filesystem.  So we move the rmap base pointers to the memory slot.

A side effect of this is that we need to store the gfn of each gpte in
the shadow pages, since the memory slot is addressed by gfn, instead of
hfn like struct page.
Signed-off-by: Izik Eidus <izik@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Now that smp_call_function_single() knows how to call a function on the
current cpu, there's no need to check explicitly.
Signed-off-by: Avi Kivity <avi@qumranet.com>

Noted by Eddie Dong.
Signed-off-by: Avi Kivity <avi@qumranet.com>

This patch modifies the management of REX prefix according behavior
I saw in Xen 3.1.  In Xen, this modification has been introduced by
Jan Beulich.

http://lists.xensource.com/archives/html/xen-changelog/2007-01/msg00081.htmlSigned-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>

The only valid case is on protected page access, other cases are errors.
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Remove no_wb, use dst.type = OP_NONE instead, idea stollen from xen-3.1
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>

Remove _eflags and use directly ctxt->eflags. Caching eflags is not needed as
it is restored to vcpu by kvm_main.c:emulate_instruction() from ctxt->eflags
only if emulation doesn't fail.
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>

To improve readability, move push, writeback, and grp 1a/2/3/4/5/9 emulation
parts into functions.
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>

This patch removes the fault injected when the guest attempts to set reserved
bits in cr3.  X86 hardware doesn't generate a fault when setting reserved bits.
The result of this patch is that vmware-server, running within a kvm guest,
boots and runs memtest from an iso.
Signed-off-by: Ryan Harper <ryanh@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

When we allow guest page faults to reach the guests directly, we lose
the fault tracking which allows us to detect demand paging.  So we provide
an alternate mechnism by clearing the accessed bit when we set a pte, and
checking it later to see if the guest actually used it.
Signed-off-by: Avi Kivity <avi@qumranet.com>

There are two classes of page faults trapped by kvm:
 - host page faults, where the fault is needed to allow kvm to install
   the shadow pte or update the guest accessed and dirty bits
 - guest page faults, where the guest has faulted and kvm simply injects
   the fault back into the guest to handle

The second class, guest page faults, is pure overhead.  We can eliminate
some of it on vmx using the following evil trick:
 - when we set up a shadow page table entry, if the corresponding guest pte
   is not present, set up the shadow pte as not present
 - if the guest pte _is_ present, mark the shadow pte as present but also
   set one of the reserved bits in the shadow pte
 - tell the vmx hardware not to trap faults which have the present bit clear

With this, normal page-not-present faults go directly to the guest,
bypassing kvm entirely.

Unfortunately, this trick only works on Intel hardware, as AMD lacks a
way to discriminate among page faults based on error code.  It is also
a little risky since it uses reserved bits which might become unreserved
in the future, so a module parameter is provided to disable it.
Signed-off-by: Avi Kivity <avi@qumranet.com>