1 #ifndef __LINUX_KVM_PARA_H
2 #define __LINUX_KVM_PARA_H
5 * Guest OS interface for KVM paravirtualization
7 * Note: this interface is totally experimental, and is certain to change
12 * Per-VCPU descriptor area shared between guest and host. Writable to
13 * both guest and host. Registered with the host by the guest when
14 * a guest acknowledges paravirtual mode.
16 * NOTE: all addresses are guest-physical addresses (gpa), to make it
17 * easier for the hypervisor to map between the various addresses.
19 struct kvm_vcpu_para_state {
21 * API version information for compatibility. If there's any support
22 * mismatch (too old host trying to execute too new guest) then
23 * the host will deny entry into paravirtual mode. Any other
24 * combination (new host + old guest and new host + new guest)
25 * is supposed to work - new host versions will support all old
34 * The address of the vm exit instruction (VMCALL or VMMCALL),
35 * which the host will patch according to the CPU model the
40 } __attribute__ ((aligned(PAGE_SIZE)));
42 #define KVM_PARA_API_VERSION 1
45 * This is used for an RDMSR's ECX parameter to probe for a KVM host.
46 * Hopefully no CPU vendor will use up this number. This is placed well
47 * out of way of the typical space occupied by CPU vendors' MSR indices,
48 * and we think (or at least hope) it wont be occupied in the future
51 #define MSR_KVM_API_MAGIC 0x87655678