linux-stable.git/include/linux/kvm.h, branch v3.6.3

KVM: PPC: Book3S HV: Make the guest hash table size configurable

2012-05-30T09:43:10+00:00

This adds a new ioctl to enable userspace to control the size of the guest
hashed page table (HPT) and to clear it out when resetting the guest.
The KVM_PPC_ALLOCATE_HTAB ioctl is a VM ioctl and takes as its parameter
a pointer to a u32 containing the desired order of the HPT (log base 2
of the size in bytes), which is updated on successful return to the
actual order of the HPT which was allocated.

There must be no vcpus running at the time of this ioctl.  To enforce
this, we now keep a count of the number of vcpus running in
kvm->arch.vcpus_running.

If the ioctl is called when a HPT has already been allocated, we don't
reallocate the HPT but just clear it out.  We first clear the
kvm->arch.rma_setup_done flag, which has two effects: (a) since we hold
the kvm->lock mutex, it will prevent any vcpus from starting to run until
we're done, and (b) it means that the first vcpu to run after we're done
will re-establish the VRMA if necessary.

If userspace doesn't call this ioctl before running the first vcpu, the
kernel will allocate a default-sized HPT at that point.  We do it then
rather than when creating the VM, as the code did previously, so that
userspace has a chance to do the ioctl if it wants.

When allocating the HPT, we can allocate either from the kernel page
allocator, or from the preallocated pool.  If userspace is asking for
a different size from the preallocated HPTs, we first try to allocate
using the kernel page allocator.  Then we try to allocate from the
preallocated pool, and then if that fails, we try allocating decreasing
sizes from the kernel page allocator, down to the minimum size allowed
(256kB).  Note that the kernel page allocator limits allocations to
1 << CONFIG_FORCE_MAX_ZONEORDER pages, which by default corresponds to
16MB (on 64-bit powerpc, at least).

Signed-off-by: Paul Mackerras 
[agraf: fix module compilation]
Signed-off-by: Alexander Graf

KVM: s390: add capability indicating COW support

2012-05-18T00:06:01+00:00

Currently qemu/kvm on s390 uses a guest mapping that does not
allow the guest backing page table to be write-protected to
support older systems. On those older systems a host write
protection fault will be delivered to the guest.

Newer systems allow to write-protect the guest backing memory
and let the fault be delivered to the host, thus allowing COW.

Use a capability bit to tell qemu if that is possible.

Signed-off-by: Christian Borntraeger 
Acked-by: Heiko Carstens 
Signed-off-by: Marcelo Tosatti

kvm/powerpc: Add new ioctl to retreive server MMU infos

2012-05-06T14:19:12+00:00

This is necessary for qemu to be able to pass the right information
to the guest, such as the supported page sizes and corresponding
encodings in the SLB and hash table, which can vary depending
on the processor type, the type of KVM used (PR vs HV) and the
version of KVM

Signed-off-by: Benjamin Herrenschmidt 
[agraf: fix compilation on hv, adjust for newer ioctl numbers]
Signed-off-by: Alexander Graf

KVM: Introduce direct MSI message injection for in-kernel irqchips

2012-04-24T12:59:47+00:00

Currently, MSI messages can only be injected to in-kernel irqchips by
defining a corresponding IRQ route for each message. This is not only
unhandy if the MSI messages are generated "on the fly" by user space,
IRQ routes are a limited resource that user space has to manage
carefully.

By providing a direct injection path, we can both avoid using up limited
resources and simplify the necessary steps for user land.

Signed-off-by: Jan Kiszka 
Signed-off-by: Avi Kivity

KVM: x86: Add ioctl for KVM_KVMCLOCK_CTRL

2012-04-08T09:49:01+00:00

Now that we have a flag that will tell the guest it was suspended, create an
interface for that communication using a KVM ioctl.

Signed-off-by: Eric B Munson 
Signed-off-by: Marcelo Tosatti 
Signed-off-by: Avi Kivity

KVM: Allow host IRQ sharing for assigned PCI 2.3 devices

2012-03-08T12:11:36+00:00

PCI 2.3 allows to generically disable IRQ sources at device level. This
enables us to share legacy IRQs of such devices with other host devices
when passing them to a guest.

The new IRQ sharing feature introduced here is optional, user space has
to request it explicitly. Moreover, user space can inform us about its
view of PCI_COMMAND_INTX_DISABLE so that we can avoid unmasking the
interrupt and signaling it if the guest masked it via the virtualized
PCI config space.

Signed-off-by: Jan Kiszka 
Acked-by: Alex Williamson 
Acked-by: Michael S. Tsirkin 
Signed-off-by: Avi Kivity

KVM: PPC: Add support for explicit HIOR setting

2012-03-05T12:52:41+00:00

Until now, we always set HIOR based on the PVR, but this is just wrong.
Instead, we should be setting HIOR explicitly, so user space can decide
what the initial HIOR value is - just like on real hardware.

We keep the old PVR based way around for backwards compatibility, but
once user space uses the SET_ONE_REG based method, we drop the PVR logic.

Signed-off-by: Alexander Graf 
Signed-off-by: Avi Kivity

KVM: PPC: Add generic single register ioctls

2012-03-05T12:52:40+00:00

Right now we transfer a static struct every time we want to get or set
registers. Unfortunately, over time we realize that there are more of
these than we thought of before and the extensibility and flexibility of
transferring a full struct every time is limited.

So this is a new approach to the problem. With these new ioctls, we can
get and set a single register that is identified by an ID. This allows for
very precise and limited transmittal of data. When we later realize that
it's a better idea to shove over multiple registers at once, we can reuse
most of the infrastructure and simply implement a GET_MANY_REGS / SET_MANY_REGS
interface.

Signed-off-by: Alexander Graf 
Signed-off-by: Avi Kivity

KVM: PPC: e500: MMU API

2012-03-05T12:52:24+00:00

This implements a shared-memory API for giving host userspace access to
the guest's TLB.

Signed-off-by: Scott Wood 
Signed-off-by: Alexander Graf 
Signed-off-by: Avi Kivity

KVM: provide synchronous registers in kvm_run

2012-03-05T12:52:22+00:00

On some cpus the overhead for virtualization instructions is in the same
range as a system call. Having to call multiple ioctls to get set registers
will make certain userspace handled exits more expensive than necessary.
Lets provide a section in kvm_run that works as a shared save area
for guest registers.
We also provide two 64bit flags fields (architecture specific), that will
specify
1. which parts of these fields are valid.
2. which registers were modified by userspace

Each bit for these flag fields will define a group of registers (like
general purpose) or a single register.

Signed-off-by: Christian Borntraeger 
Signed-off-by: Marcelo Tosatti 
Signed-off-by: Avi Kivity