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When we migrate a kvm guest that uses pvclock between two hosts, we may suffer a large skew. This is because there can be significant differences between the monotonic clock of the hosts involved. When a new host with a much larger monotonic time starts running the guest, the view of time will be significantly impacted. Situation is much worse when we do the opposite, and migrate to a host with a smaller monotonic clock. This proposed ioctl will allow userspace to inform us what is the monotonic clock value in the source host, so we can keep the time skew short, and more importantly, never goes backwards. Userspace may also need to trigger the current data, since from the first migration onwards, it won't be reflected by a simple call to clock_gettime() anymore. [marcelo: future-proof abi with a flags field] [jan: fix KVM_GET_CLOCK by clearing flags field instead of checking it] Signed-off-by: Glauber Costa <glommer@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
819 lines
21 KiB
Text
819 lines
21 KiB
Text
The Definitive KVM (Kernel-based Virtual Machine) API Documentation
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===================================================================
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1. General description
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The kvm API is a set of ioctls that are issued to control various aspects
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of a virtual machine. The ioctls belong to three classes
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- System ioctls: These query and set global attributes which affect the
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whole kvm subsystem. In addition a system ioctl is used to create
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virtual machines
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- VM ioctls: These query and set attributes that affect an entire virtual
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machine, for example memory layout. In addition a VM ioctl is used to
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create virtual cpus (vcpus).
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Only run VM ioctls from the same process (address space) that was used
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to create the VM.
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- vcpu ioctls: These query and set attributes that control the operation
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of a single virtual cpu.
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Only run vcpu ioctls from the same thread that was used to create the
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vcpu.
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2. File descritpors
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The kvm API is centered around file descriptors. An initial
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open("/dev/kvm") obtains a handle to the kvm subsystem; this handle
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can be used to issue system ioctls. A KVM_CREATE_VM ioctl on this
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handle will create a VM file descripror which can be used to issue VM
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ioctls. A KVM_CREATE_VCPU ioctl on a VM fd will create a virtual cpu
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and return a file descriptor pointing to it. Finally, ioctls on a vcpu
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fd can be used to control the vcpu, including the important task of
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actually running guest code.
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In general file descriptors can be migrated among processes by means
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of fork() and the SCM_RIGHTS facility of unix domain socket. These
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kinds of tricks are explicitly not supported by kvm. While they will
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not cause harm to the host, their actual behavior is not guaranteed by
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the API. The only supported use is one virtual machine per process,
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and one vcpu per thread.
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3. Extensions
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As of Linux 2.6.22, the KVM ABI has been stabilized: no backward
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incompatible change are allowed. However, there is an extension
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facility that allows backward-compatible extensions to the API to be
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queried and used.
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The extension mechanism is not based on on the Linux version number.
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Instead, kvm defines extension identifiers and a facility to query
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whether a particular extension identifier is available. If it is, a
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set of ioctls is available for application use.
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4. API description
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This section describes ioctls that can be used to control kvm guests.
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For each ioctl, the following information is provided along with a
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description:
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Capability: which KVM extension provides this ioctl. Can be 'basic',
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which means that is will be provided by any kernel that supports
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API version 12 (see section 4.1), or a KVM_CAP_xyz constant, which
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means availability needs to be checked with KVM_CHECK_EXTENSION
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(see section 4.4).
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Architectures: which instruction set architectures provide this ioctl.
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x86 includes both i386 and x86_64.
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Type: system, vm, or vcpu.
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Parameters: what parameters are accepted by the ioctl.
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Returns: the return value. General error numbers (EBADF, ENOMEM, EINVAL)
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are not detailed, but errors with specific meanings are.
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4.1 KVM_GET_API_VERSION
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Capability: basic
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Architectures: all
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Type: system ioctl
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Parameters: none
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Returns: the constant KVM_API_VERSION (=12)
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This identifies the API version as the stable kvm API. It is not
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expected that this number will change. However, Linux 2.6.20 and
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2.6.21 report earlier versions; these are not documented and not
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supported. Applications should refuse to run if KVM_GET_API_VERSION
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returns a value other than 12. If this check passes, all ioctls
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described as 'basic' will be available.
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4.2 KVM_CREATE_VM
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Capability: basic
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Architectures: all
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Type: system ioctl
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Parameters: none
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Returns: a VM fd that can be used to control the new virtual machine.
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The new VM has no virtual cpus and no memory. An mmap() of a VM fd
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will access the virtual machine's physical address space; offset zero
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corresponds to guest physical address zero. Use of mmap() on a VM fd
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is discouraged if userspace memory allocation (KVM_CAP_USER_MEMORY) is
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available.
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4.3 KVM_GET_MSR_INDEX_LIST
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Capability: basic
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Architectures: x86
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Type: system
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Parameters: struct kvm_msr_list (in/out)
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Returns: 0 on success; -1 on error
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Errors:
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E2BIG: the msr index list is to be to fit in the array specified by
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the user.
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struct kvm_msr_list {
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__u32 nmsrs; /* number of msrs in entries */
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__u32 indices[0];
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};
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This ioctl returns the guest msrs that are supported. The list varies
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by kvm version and host processor, but does not change otherwise. The
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user fills in the size of the indices array in nmsrs, and in return
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kvm adjusts nmsrs to reflect the actual number of msrs and fills in
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the indices array with their numbers.
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4.4 KVM_CHECK_EXTENSION
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Capability: basic
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Architectures: all
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Type: system ioctl
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Parameters: extension identifier (KVM_CAP_*)
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Returns: 0 if unsupported; 1 (or some other positive integer) if supported
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The API allows the application to query about extensions to the core
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kvm API. Userspace passes an extension identifier (an integer) and
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receives an integer that describes the extension availability.
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Generally 0 means no and 1 means yes, but some extensions may report
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additional information in the integer return value.
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4.5 KVM_GET_VCPU_MMAP_SIZE
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Capability: basic
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Architectures: all
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Type: system ioctl
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Parameters: none
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Returns: size of vcpu mmap area, in bytes
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The KVM_RUN ioctl (cf.) communicates with userspace via a shared
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memory region. This ioctl returns the size of that region. See the
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KVM_RUN documentation for details.
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4.6 KVM_SET_MEMORY_REGION
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Capability: basic
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Architectures: all
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Type: vm ioctl
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Parameters: struct kvm_memory_region (in)
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Returns: 0 on success, -1 on error
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struct kvm_memory_region {
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__u32 slot;
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__u32 flags;
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__u64 guest_phys_addr;
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__u64 memory_size; /* bytes */
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};
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/* for kvm_memory_region::flags */
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#define KVM_MEM_LOG_DIRTY_PAGES 1UL
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This ioctl allows the user to create or modify a guest physical memory
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slot. When changing an existing slot, it may be moved in the guest
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physical memory space, or its flags may be modified. It may not be
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resized. Slots may not overlap.
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The flags field supports just one flag, KVM_MEM_LOG_DIRTY_PAGES, which
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instructs kvm to keep track of writes to memory within the slot. See
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the KVM_GET_DIRTY_LOG ioctl.
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It is recommended to use the KVM_SET_USER_MEMORY_REGION ioctl instead
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of this API, if available. This newer API allows placing guest memory
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at specified locations in the host address space, yielding better
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control and easy access.
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4.6 KVM_CREATE_VCPU
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Capability: basic
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Architectures: all
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Type: vm ioctl
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Parameters: vcpu id (apic id on x86)
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Returns: vcpu fd on success, -1 on error
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This API adds a vcpu to a virtual machine. The vcpu id is a small integer
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in the range [0, max_vcpus).
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4.7 KVM_GET_DIRTY_LOG (vm ioctl)
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Capability: basic
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Architectures: x86
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Type: vm ioctl
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Parameters: struct kvm_dirty_log (in/out)
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Returns: 0 on success, -1 on error
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/* for KVM_GET_DIRTY_LOG */
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struct kvm_dirty_log {
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__u32 slot;
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__u32 padding;
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union {
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void __user *dirty_bitmap; /* one bit per page */
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__u64 padding;
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};
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};
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Given a memory slot, return a bitmap containing any pages dirtied
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since the last call to this ioctl. Bit 0 is the first page in the
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memory slot. Ensure the entire structure is cleared to avoid padding
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issues.
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4.8 KVM_SET_MEMORY_ALIAS
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Capability: basic
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Architectures: x86
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Type: vm ioctl
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Parameters: struct kvm_memory_alias (in)
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Returns: 0 (success), -1 (error)
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struct kvm_memory_alias {
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__u32 slot; /* this has a different namespace than memory slots */
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__u32 flags;
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__u64 guest_phys_addr;
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__u64 memory_size;
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__u64 target_phys_addr;
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};
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Defines a guest physical address space region as an alias to another
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region. Useful for aliased address, for example the VGA low memory
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window. Should not be used with userspace memory.
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4.9 KVM_RUN
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Capability: basic
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Architectures: all
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Type: vcpu ioctl
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Parameters: none
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Returns: 0 on success, -1 on error
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Errors:
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EINTR: an unmasked signal is pending
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This ioctl is used to run a guest virtual cpu. While there are no
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explicit parameters, there is an implicit parameter block that can be
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obtained by mmap()ing the vcpu fd at offset 0, with the size given by
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KVM_GET_VCPU_MMAP_SIZE. The parameter block is formatted as a 'struct
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kvm_run' (see below).
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4.10 KVM_GET_REGS
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Capability: basic
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Architectures: all
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Type: vcpu ioctl
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Parameters: struct kvm_regs (out)
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Returns: 0 on success, -1 on error
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Reads the general purpose registers from the vcpu.
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/* x86 */
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struct kvm_regs {
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/* out (KVM_GET_REGS) / in (KVM_SET_REGS) */
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__u64 rax, rbx, rcx, rdx;
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__u64 rsi, rdi, rsp, rbp;
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__u64 r8, r9, r10, r11;
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__u64 r12, r13, r14, r15;
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__u64 rip, rflags;
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};
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4.11 KVM_SET_REGS
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Capability: basic
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Architectures: all
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Type: vcpu ioctl
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Parameters: struct kvm_regs (in)
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Returns: 0 on success, -1 on error
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Writes the general purpose registers into the vcpu.
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See KVM_GET_REGS for the data structure.
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4.12 KVM_GET_SREGS
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Capability: basic
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Architectures: x86
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Type: vcpu ioctl
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Parameters: struct kvm_sregs (out)
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Returns: 0 on success, -1 on error
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Reads special registers from the vcpu.
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/* x86 */
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struct kvm_sregs {
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struct kvm_segment cs, ds, es, fs, gs, ss;
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struct kvm_segment tr, ldt;
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struct kvm_dtable gdt, idt;
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__u64 cr0, cr2, cr3, cr4, cr8;
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__u64 efer;
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__u64 apic_base;
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__u64 interrupt_bitmap[(KVM_NR_INTERRUPTS + 63) / 64];
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};
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interrupt_bitmap is a bitmap of pending external interrupts. At most
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one bit may be set. This interrupt has been acknowledged by the APIC
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but not yet injected into the cpu core.
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4.13 KVM_SET_SREGS
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Capability: basic
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Architectures: x86
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Type: vcpu ioctl
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Parameters: struct kvm_sregs (in)
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Returns: 0 on success, -1 on error
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Writes special registers into the vcpu. See KVM_GET_SREGS for the
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data structures.
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4.14 KVM_TRANSLATE
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Capability: basic
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Architectures: x86
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Type: vcpu ioctl
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Parameters: struct kvm_translation (in/out)
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Returns: 0 on success, -1 on error
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Translates a virtual address according to the vcpu's current address
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translation mode.
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struct kvm_translation {
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/* in */
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__u64 linear_address;
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/* out */
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__u64 physical_address;
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__u8 valid;
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__u8 writeable;
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__u8 usermode;
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__u8 pad[5];
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};
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4.15 KVM_INTERRUPT
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Capability: basic
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Architectures: x86
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Type: vcpu ioctl
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Parameters: struct kvm_interrupt (in)
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Returns: 0 on success, -1 on error
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Queues a hardware interrupt vector to be injected. This is only
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useful if in-kernel local APIC is not used.
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/* for KVM_INTERRUPT */
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struct kvm_interrupt {
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/* in */
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__u32 irq;
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};
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Note 'irq' is an interrupt vector, not an interrupt pin or line.
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4.16 KVM_DEBUG_GUEST
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Capability: basic
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Architectures: none
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Type: vcpu ioctl
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Parameters: none)
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Returns: -1 on error
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Support for this has been removed. Use KVM_SET_GUEST_DEBUG instead.
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4.17 KVM_GET_MSRS
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Capability: basic
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Architectures: x86
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Type: vcpu ioctl
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Parameters: struct kvm_msrs (in/out)
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Returns: 0 on success, -1 on error
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Reads model-specific registers from the vcpu. Supported msr indices can
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be obtained using KVM_GET_MSR_INDEX_LIST.
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struct kvm_msrs {
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__u32 nmsrs; /* number of msrs in entries */
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__u32 pad;
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struct kvm_msr_entry entries[0];
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};
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struct kvm_msr_entry {
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__u32 index;
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__u32 reserved;
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__u64 data;
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};
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Application code should set the 'nmsrs' member (which indicates the
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size of the entries array) and the 'index' member of each array entry.
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kvm will fill in the 'data' member.
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4.18 KVM_SET_MSRS
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Capability: basic
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Architectures: x86
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Type: vcpu ioctl
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Parameters: struct kvm_msrs (in)
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Returns: 0 on success, -1 on error
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Writes model-specific registers to the vcpu. See KVM_GET_MSRS for the
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data structures.
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Application code should set the 'nmsrs' member (which indicates the
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size of the entries array), and the 'index' and 'data' members of each
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array entry.
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4.19 KVM_SET_CPUID
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Capability: basic
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Architectures: x86
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Type: vcpu ioctl
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Parameters: struct kvm_cpuid (in)
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Returns: 0 on success, -1 on error
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Defines the vcpu responses to the cpuid instruction. Applications
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should use the KVM_SET_CPUID2 ioctl if available.
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struct kvm_cpuid_entry {
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__u32 function;
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__u32 eax;
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__u32 ebx;
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__u32 ecx;
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__u32 edx;
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__u32 padding;
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};
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/* for KVM_SET_CPUID */
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struct kvm_cpuid {
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__u32 nent;
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__u32 padding;
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struct kvm_cpuid_entry entries[0];
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};
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4.20 KVM_SET_SIGNAL_MASK
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Capability: basic
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Architectures: x86
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Type: vcpu ioctl
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Parameters: struct kvm_signal_mask (in)
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Returns: 0 on success, -1 on error
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Defines which signals are blocked during execution of KVM_RUN. This
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signal mask temporarily overrides the threads signal mask. Any
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unblocked signal received (except SIGKILL and SIGSTOP, which retain
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their traditional behaviour) will cause KVM_RUN to return with -EINTR.
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Note the signal will only be delivered if not blocked by the original
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signal mask.
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/* for KVM_SET_SIGNAL_MASK */
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struct kvm_signal_mask {
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__u32 len;
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__u8 sigset[0];
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};
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4.21 KVM_GET_FPU
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Capability: basic
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Architectures: x86
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Type: vcpu ioctl
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Parameters: struct kvm_fpu (out)
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Returns: 0 on success, -1 on error
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Reads the floating point state from the vcpu.
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/* for KVM_GET_FPU and KVM_SET_FPU */
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struct kvm_fpu {
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__u8 fpr[8][16];
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__u16 fcw;
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__u16 fsw;
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__u8 ftwx; /* in fxsave format */
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__u8 pad1;
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__u16 last_opcode;
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__u64 last_ip;
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__u64 last_dp;
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__u8 xmm[16][16];
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__u32 mxcsr;
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__u32 pad2;
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};
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4.22 KVM_SET_FPU
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Capability: basic
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Architectures: x86
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Type: vcpu ioctl
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Parameters: struct kvm_fpu (in)
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Returns: 0 on success, -1 on error
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Writes the floating point state to the vcpu.
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/* for KVM_GET_FPU and KVM_SET_FPU */
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struct kvm_fpu {
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__u8 fpr[8][16];
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__u16 fcw;
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__u16 fsw;
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__u8 ftwx; /* in fxsave format */
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__u8 pad1;
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__u16 last_opcode;
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__u64 last_ip;
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__u64 last_dp;
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__u8 xmm[16][16];
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__u32 mxcsr;
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__u32 pad2;
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};
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4.23 KVM_CREATE_IRQCHIP
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Capability: KVM_CAP_IRQCHIP
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Architectures: x86, ia64
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Type: vm ioctl
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Parameters: none
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Returns: 0 on success, -1 on error
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|
Creates an interrupt controller model in the kernel. On x86, creates a virtual
|
|
ioapic, a virtual PIC (two PICs, nested), and sets up future vcpus to have a
|
|
local APIC. IRQ routing for GSIs 0-15 is set to both PIC and IOAPIC; GSI 16-23
|
|
only go to the IOAPIC. On ia64, a IOSAPIC is created.
|
|
|
|
4.24 KVM_IRQ_LINE
|
|
|
|
Capability: KVM_CAP_IRQCHIP
|
|
Architectures: x86, ia64
|
|
Type: vm ioctl
|
|
Parameters: struct kvm_irq_level
|
|
Returns: 0 on success, -1 on error
|
|
|
|
Sets the level of a GSI input to the interrupt controller model in the kernel.
|
|
Requires that an interrupt controller model has been previously created with
|
|
KVM_CREATE_IRQCHIP. Note that edge-triggered interrupts require the level
|
|
to be set to 1 and then back to 0.
|
|
|
|
struct kvm_irq_level {
|
|
union {
|
|
__u32 irq; /* GSI */
|
|
__s32 status; /* not used for KVM_IRQ_LEVEL */
|
|
};
|
|
__u32 level; /* 0 or 1 */
|
|
};
|
|
|
|
4.25 KVM_GET_IRQCHIP
|
|
|
|
Capability: KVM_CAP_IRQCHIP
|
|
Architectures: x86, ia64
|
|
Type: vm ioctl
|
|
Parameters: struct kvm_irqchip (in/out)
|
|
Returns: 0 on success, -1 on error
|
|
|
|
Reads the state of a kernel interrupt controller created with
|
|
KVM_CREATE_IRQCHIP into a buffer provided by the caller.
|
|
|
|
struct kvm_irqchip {
|
|
__u32 chip_id; /* 0 = PIC1, 1 = PIC2, 2 = IOAPIC */
|
|
__u32 pad;
|
|
union {
|
|
char dummy[512]; /* reserving space */
|
|
struct kvm_pic_state pic;
|
|
struct kvm_ioapic_state ioapic;
|
|
} chip;
|
|
};
|
|
|
|
4.26 KVM_SET_IRQCHIP
|
|
|
|
Capability: KVM_CAP_IRQCHIP
|
|
Architectures: x86, ia64
|
|
Type: vm ioctl
|
|
Parameters: struct kvm_irqchip (in)
|
|
Returns: 0 on success, -1 on error
|
|
|
|
Sets the state of a kernel interrupt controller created with
|
|
KVM_CREATE_IRQCHIP from a buffer provided by the caller.
|
|
|
|
struct kvm_irqchip {
|
|
__u32 chip_id; /* 0 = PIC1, 1 = PIC2, 2 = IOAPIC */
|
|
__u32 pad;
|
|
union {
|
|
char dummy[512]; /* reserving space */
|
|
struct kvm_pic_state pic;
|
|
struct kvm_ioapic_state ioapic;
|
|
} chip;
|
|
};
|
|
|
|
4.27 KVM_XEN_HVM_CONFIG
|
|
|
|
Capability: KVM_CAP_XEN_HVM
|
|
Architectures: x86
|
|
Type: vm ioctl
|
|
Parameters: struct kvm_xen_hvm_config (in)
|
|
Returns: 0 on success, -1 on error
|
|
|
|
Sets the MSR that the Xen HVM guest uses to initialize its hypercall
|
|
page, and provides the starting address and size of the hypercall
|
|
blobs in userspace. When the guest writes the MSR, kvm copies one
|
|
page of a blob (32- or 64-bit, depending on the vcpu mode) to guest
|
|
memory.
|
|
|
|
struct kvm_xen_hvm_config {
|
|
__u32 flags;
|
|
__u32 msr;
|
|
__u64 blob_addr_32;
|
|
__u64 blob_addr_64;
|
|
__u8 blob_size_32;
|
|
__u8 blob_size_64;
|
|
__u8 pad2[30];
|
|
};
|
|
|
|
4.27 KVM_GET_CLOCK
|
|
|
|
Capability: KVM_CAP_ADJUST_CLOCK
|
|
Architectures: x86
|
|
Type: vm ioctl
|
|
Parameters: struct kvm_clock_data (out)
|
|
Returns: 0 on success, -1 on error
|
|
|
|
Gets the current timestamp of kvmclock as seen by the current guest. In
|
|
conjunction with KVM_SET_CLOCK, it is used to ensure monotonicity on scenarios
|
|
such as migration.
|
|
|
|
struct kvm_clock_data {
|
|
__u64 clock; /* kvmclock current value */
|
|
__u32 flags;
|
|
__u32 pad[9];
|
|
};
|
|
|
|
4.28 KVM_SET_CLOCK
|
|
|
|
Capability: KVM_CAP_ADJUST_CLOCK
|
|
Architectures: x86
|
|
Type: vm ioctl
|
|
Parameters: struct kvm_clock_data (in)
|
|
Returns: 0 on success, -1 on error
|
|
|
|
Sets the current timestamp of kvmclock to the valued specific in its parameter.
|
|
In conjunction with KVM_GET_CLOCK, it is used to ensure monotonicity on scenarios
|
|
such as migration.
|
|
|
|
struct kvm_clock_data {
|
|
__u64 clock; /* kvmclock current value */
|
|
__u32 flags;
|
|
__u32 pad[9];
|
|
};
|
|
|
|
5. The kvm_run structure
|
|
|
|
Application code obtains a pointer to the kvm_run structure by
|
|
mmap()ing a vcpu fd. From that point, application code can control
|
|
execution by changing fields in kvm_run prior to calling the KVM_RUN
|
|
ioctl, and obtain information about the reason KVM_RUN returned by
|
|
looking up structure members.
|
|
|
|
struct kvm_run {
|
|
/* in */
|
|
__u8 request_interrupt_window;
|
|
|
|
Request that KVM_RUN return when it becomes possible to inject external
|
|
interrupts into the guest. Useful in conjunction with KVM_INTERRUPT.
|
|
|
|
__u8 padding1[7];
|
|
|
|
/* out */
|
|
__u32 exit_reason;
|
|
|
|
When KVM_RUN has returned successfully (return value 0), this informs
|
|
application code why KVM_RUN has returned. Allowable values for this
|
|
field are detailed below.
|
|
|
|
__u8 ready_for_interrupt_injection;
|
|
|
|
If request_interrupt_window has been specified, this field indicates
|
|
an interrupt can be injected now with KVM_INTERRUPT.
|
|
|
|
__u8 if_flag;
|
|
|
|
The value of the current interrupt flag. Only valid if in-kernel
|
|
local APIC is not used.
|
|
|
|
__u8 padding2[2];
|
|
|
|
/* in (pre_kvm_run), out (post_kvm_run) */
|
|
__u64 cr8;
|
|
|
|
The value of the cr8 register. Only valid if in-kernel local APIC is
|
|
not used. Both input and output.
|
|
|
|
__u64 apic_base;
|
|
|
|
The value of the APIC BASE msr. Only valid if in-kernel local
|
|
APIC is not used. Both input and output.
|
|
|
|
union {
|
|
/* KVM_EXIT_UNKNOWN */
|
|
struct {
|
|
__u64 hardware_exit_reason;
|
|
} hw;
|
|
|
|
If exit_reason is KVM_EXIT_UNKNOWN, the vcpu has exited due to unknown
|
|
reasons. Further architecture-specific information is available in
|
|
hardware_exit_reason.
|
|
|
|
/* KVM_EXIT_FAIL_ENTRY */
|
|
struct {
|
|
__u64 hardware_entry_failure_reason;
|
|
} fail_entry;
|
|
|
|
If exit_reason is KVM_EXIT_FAIL_ENTRY, the vcpu could not be run due
|
|
to unknown reasons. Further architecture-specific information is
|
|
available in hardware_entry_failure_reason.
|
|
|
|
/* KVM_EXIT_EXCEPTION */
|
|
struct {
|
|
__u32 exception;
|
|
__u32 error_code;
|
|
} ex;
|
|
|
|
Unused.
|
|
|
|
/* KVM_EXIT_IO */
|
|
struct {
|
|
#define KVM_EXIT_IO_IN 0
|
|
#define KVM_EXIT_IO_OUT 1
|
|
__u8 direction;
|
|
__u8 size; /* bytes */
|
|
__u16 port;
|
|
__u32 count;
|
|
__u64 data_offset; /* relative to kvm_run start */
|
|
} io;
|
|
|
|
If exit_reason is KVM_EXIT_IO_IN or KVM_EXIT_IO_OUT, then the vcpu has
|
|
executed a port I/O instruction which could not be satisfied by kvm.
|
|
data_offset describes where the data is located (KVM_EXIT_IO_OUT) or
|
|
where kvm expects application code to place the data for the next
|
|
KVM_RUN invocation (KVM_EXIT_IO_IN). Data format is a patcked array.
|
|
|
|
struct {
|
|
struct kvm_debug_exit_arch arch;
|
|
} debug;
|
|
|
|
Unused.
|
|
|
|
/* KVM_EXIT_MMIO */
|
|
struct {
|
|
__u64 phys_addr;
|
|
__u8 data[8];
|
|
__u32 len;
|
|
__u8 is_write;
|
|
} mmio;
|
|
|
|
If exit_reason is KVM_EXIT_MMIO or KVM_EXIT_IO_OUT, then the vcpu has
|
|
executed a memory-mapped I/O instruction which could not be satisfied
|
|
by kvm. The 'data' member contains the written data if 'is_write' is
|
|
true, and should be filled by application code otherwise.
|
|
|
|
/* KVM_EXIT_HYPERCALL */
|
|
struct {
|
|
__u64 nr;
|
|
__u64 args[6];
|
|
__u64 ret;
|
|
__u32 longmode;
|
|
__u32 pad;
|
|
} hypercall;
|
|
|
|
Unused.
|
|
|
|
/* KVM_EXIT_TPR_ACCESS */
|
|
struct {
|
|
__u64 rip;
|
|
__u32 is_write;
|
|
__u32 pad;
|
|
} tpr_access;
|
|
|
|
To be documented (KVM_TPR_ACCESS_REPORTING).
|
|
|
|
/* KVM_EXIT_S390_SIEIC */
|
|
struct {
|
|
__u8 icptcode;
|
|
__u64 mask; /* psw upper half */
|
|
__u64 addr; /* psw lower half */
|
|
__u16 ipa;
|
|
__u32 ipb;
|
|
} s390_sieic;
|
|
|
|
s390 specific.
|
|
|
|
/* KVM_EXIT_S390_RESET */
|
|
#define KVM_S390_RESET_POR 1
|
|
#define KVM_S390_RESET_CLEAR 2
|
|
#define KVM_S390_RESET_SUBSYSTEM 4
|
|
#define KVM_S390_RESET_CPU_INIT 8
|
|
#define KVM_S390_RESET_IPL 16
|
|
__u64 s390_reset_flags;
|
|
|
|
s390 specific.
|
|
|
|
/* KVM_EXIT_DCR */
|
|
struct {
|
|
__u32 dcrn;
|
|
__u32 data;
|
|
__u8 is_write;
|
|
} dcr;
|
|
|
|
powerpc specific.
|
|
|
|
/* Fix the size of the union. */
|
|
char padding[256];
|
|
};
|
|
};
|