include/sysemu/kvm.h - qemu - Git at Google

 /*
  * QEMU KVM support
  *
  * Copyright IBM, Corp. 2008
  *
  * Authors:
  *  Anthony Liguori   <aliguori@us.ibm.com>
  *
  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  * See the COPYING file in the top-level directory.
  *
  */

 #ifndef QEMU_KVM_H
 #define QEMU_KVM_H

 #include "qemu/queue.h"
 #include "qom/cpu.h"
 #include "exec/memattrs.h"
 #include "hw/irq.h"

 #ifdef CONFIG_KVM
 #include <linux/kvm.h>
 #include <linux/kvm_para.h>
 #else
 /* These constants must never be used at runtime if kvm_enabled() is false.
  * They exist so we don't need #ifdefs around KVM-specific code that already
  * checks kvm_enabled() properly.
  */
 #define KVM_CPUID_SIGNATURE      0
 #define KVM_CPUID_FEATURES       0
 #define KVM_FEATURE_CLOCKSOURCE  0
 #define KVM_FEATURE_NOP_IO_DELAY 0
 #define KVM_FEATURE_MMU_OP       0
 #define KVM_FEATURE_CLOCKSOURCE2 0
 #define KVM_FEATURE_ASYNC_PF     0
 #define KVM_FEATURE_STEAL_TIME   0
 #define KVM_FEATURE_PV_EOI       0
 #define KVM_FEATURE_CLOCKSOURCE_STABLE_BIT 0
 #endif

 extern bool kvm_allowed;
 extern bool kvm_kernel_irqchip;
 extern bool kvm_split_irqchip;
 extern bool kvm_async_interrupts_allowed;
 extern bool kvm_halt_in_kernel_allowed;
 extern bool kvm_eventfds_allowed;
 extern bool kvm_irqfds_allowed;
 extern bool kvm_resamplefds_allowed;
 extern bool kvm_msi_via_irqfd_allowed;
 extern bool kvm_gsi_routing_allowed;
 extern bool kvm_gsi_direct_mapping;
 extern bool kvm_readonly_mem_allowed;
 extern bool kvm_direct_msi_allowed;
 extern bool kvm_ioeventfd_any_length_allowed;

 #if defined CONFIG_KVM || !defined NEED_CPU_H
 #define kvm_enabled()           (kvm_allowed)
 /**
  * kvm_irqchip_in_kernel:
  *
  * Returns: true if the user asked us to create an in-kernel
  * irqchip via the "kernel_irqchip=on" machine option.
  * What this actually means is architecture and machine model
  * specific: on PC, for instance, it means that the LAPIC,
  * IOAPIC and PIT are all in kernel. This function should never
  * be used from generic target-independent code: use one of the
  * following functions or some other specific check instead.
  */
 #define kvm_irqchip_in_kernel() (kvm_kernel_irqchip)

 /**
  * kvm_irqchip_is_split:
  *
  * Returns: true if the user asked us to split the irqchip
  * implementation between user and kernel space. The details are
  * architecture and machine specific. On PC, it means that the PIC,
  * IOAPIC, and PIT are in user space while the LAPIC is in the kernel.
  */
 #define kvm_irqchip_is_split() (kvm_split_irqchip)

 /**
  * kvm_async_interrupts_enabled:
  *
  * Returns: true if we can deliver interrupts to KVM
  * asynchronously (ie by ioctl from any thread at any time)
  * rather than having to do interrupt delivery synchronously
  * (where the vcpu must be stopped at a suitable point first).
  */
 #define kvm_async_interrupts_enabled() (kvm_async_interrupts_allowed)

 /**
  * kvm_halt_in_kernel
  *
  * Returns: true if halted cpus should still get a KVM_RUN ioctl to run
  * inside of kernel space. This only works if MP state is implemented.
  */
 #define kvm_halt_in_kernel() (kvm_halt_in_kernel_allowed)

 /**
  * kvm_eventfds_enabled:
  *
  * Returns: true if we can use eventfds to receive notifications
  * from a KVM CPU (ie the kernel supports eventds and we are running
  * with a configuration where it is meaningful to use them).
  */
 #define kvm_eventfds_enabled() (kvm_eventfds_allowed)

 /**
  * kvm_irqfds_enabled:
  *
  * Returns: true if we can use irqfds to inject interrupts into
  * a KVM CPU (ie the kernel supports irqfds and we are running
  * with a configuration where it is meaningful to use them).
  */
 #define kvm_irqfds_enabled() (kvm_irqfds_allowed)

 /**
  * kvm_resamplefds_enabled:
  *
  * Returns: true if we can use resamplefds to inject interrupts into
  * a KVM CPU (ie the kernel supports resamplefds and we are running
  * with a configuration where it is meaningful to use them).
  */
 #define kvm_resamplefds_enabled() (kvm_resamplefds_allowed)

 /**
  * kvm_msi_via_irqfd_enabled:
  *
  * Returns: true if we can route a PCI MSI (Message Signaled Interrupt)
  * to a KVM CPU via an irqfd. This requires that the kernel supports
  * this and that we're running in a configuration that permits it.
  */
 #define kvm_msi_via_irqfd_enabled() (kvm_msi_via_irqfd_allowed)

 /**
  * kvm_gsi_routing_enabled:
  *
  * Returns: true if GSI routing is enabled (ie the kernel supports
  * it and we're running in a configuration that permits it).
  */
 #define kvm_gsi_routing_enabled() (kvm_gsi_routing_allowed)

 /**
  * kvm_gsi_direct_mapping:
  *
  * Returns: true if GSI direct mapping is enabled.
  */
 #define kvm_gsi_direct_mapping() (kvm_gsi_direct_mapping)

 /**
  * kvm_readonly_mem_enabled:
  *
  * Returns: true if KVM readonly memory is enabled (ie the kernel
  * supports it and we're running in a configuration that permits it).
  */
 #define kvm_readonly_mem_enabled() (kvm_readonly_mem_allowed)

 /**
  * kvm_direct_msi_enabled:
  *
  * Returns: true if KVM allows direct MSI injection.
  */
 #define kvm_direct_msi_enabled() (kvm_direct_msi_allowed)

 /**
  * kvm_ioeventfd_any_length_enabled:
  * Returns: true if KVM allows any length io eventfd.
  */
 #define kvm_ioeventfd_any_length_enabled() (kvm_ioeventfd_any_length_allowed)

 #else
 #define kvm_enabled()           (0)
 #define kvm_irqchip_in_kernel() (false)
 #define kvm_irqchip_is_split() (false)
 #define kvm_async_interrupts_enabled() (false)
 #define kvm_halt_in_kernel() (false)
 #define kvm_eventfds_enabled() (false)
 #define kvm_irqfds_enabled() (false)
 #define kvm_resamplefds_enabled() (false)
 #define kvm_msi_via_irqfd_enabled() (false)
 #define kvm_gsi_routing_allowed() (false)
 #define kvm_gsi_direct_mapping() (false)
 #define kvm_readonly_mem_enabled() (false)
 #define kvm_direct_msi_enabled() (false)
 #define kvm_ioeventfd_any_length_enabled() (false)
 #endif

 struct kvm_run;
 struct kvm_lapic_state;
 struct kvm_irq_routing_entry;

 typedef struct KVMCapabilityInfo {
     const char *name;
     int value;
 } KVMCapabilityInfo;

 #define KVM_CAP_INFO(CAP) { "KVM_CAP_" stringify(CAP), KVM_CAP_##CAP }
 #define KVM_CAP_LAST_INFO { NULL, 0 }

 struct KVMState;
 typedef struct KVMState KVMState;
 extern KVMState *kvm_state;

 /* external API */

 bool kvm_has_free_slot(MachineState *ms);
 int kvm_has_sync_mmu(void);
 int kvm_has_vcpu_events(void);
 int kvm_has_robust_singlestep(void);
 int kvm_has_debugregs(void);
 int kvm_has_pit_state2(void);
 int kvm_has_many_ioeventfds(void);
 int kvm_has_gsi_routing(void);
 int kvm_has_intx_set_mask(void);

 int kvm_init_vcpu(CPUState *cpu);
 int kvm_cpu_exec(CPUState *cpu);

 #ifdef NEED_CPU_H

 void kvm_setup_guest_memory(void *start, size_t size);
 void kvm_flush_coalesced_mmio_buffer(void);

 int kvm_insert_breakpoint(CPUState *cpu, target_ulong addr,
                           target_ulong len, int type);
 int kvm_remove_breakpoint(CPUState *cpu, target_ulong addr,
                           target_ulong len, int type);
 void kvm_remove_all_breakpoints(CPUState *cpu);
 int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap);
 #ifndef _WIN32
 int kvm_set_signal_mask(CPUState *cpu, const sigset_t *sigset);
 #endif

 int kvm_on_sigbus_vcpu(CPUState *cpu, int code, void *addr);
 int kvm_on_sigbus(int code, void *addr);

 /* interface with exec.c */

 void phys_mem_set_alloc(void *(*alloc)(size_t, uint64_t *align));

 /* internal API */

 int kvm_ioctl(KVMState *s, int type, ...);

 int kvm_vm_ioctl(KVMState *s, int type, ...);

 int kvm_vcpu_ioctl(CPUState *cpu, int type, ...);

 /**
  * kvm_device_ioctl - call an ioctl on a kvm device
  * @fd: The KVM device file descriptor as returned from KVM_CREATE_DEVICE
  * @type: The device-ctrl ioctl number
  *
  * Returns: -errno on error, nonnegative on success
  */
 int kvm_device_ioctl(int fd, int type, ...);

 /**
  * kvm_vm_check_attr - check for existence of a specific vm attribute
  * @s: The KVMState pointer
  * @group: the group
  * @attr: the attribute of that group to query for
  *
  * Returns: 1 if the attribute exists
  *          0 if the attribute either does not exist or if the vm device
  *            interface is unavailable
  */
 int kvm_vm_check_attr(KVMState *s, uint32_t group, uint64_t attr);

 /**
  * kvm_device_check_attr - check for existence of a specific device attribute
  * @fd: The device file descriptor
  * @group: the group
  * @attr: the attribute of that group to query for
  *
  * Returns: 1 if the attribute exists
  *          0 if the attribute either does not exist or if the vm device
  *            interface is unavailable
  */
 int kvm_device_check_attr(int fd, uint32_t group, uint64_t attr);

 /**
  * kvm_device_access - set or get value of a specific vm attribute
  * @fd: The device file descriptor
  * @group: the group
  * @attr: the attribute of that group to set or get
  * @val: pointer to a storage area for the value
  * @write: true for set and false for get operation
  *
  * This function is not allowed to fail. Use kvm_device_check_attr()
  * in order to check for the availability of optional attributes.
  */
 void kvm_device_access(int fd, int group, uint64_t attr,
                        void *val, bool write);

 /**
  * kvm_create_device - create a KVM device for the device control API
  * @KVMState: The KVMState pointer
  * @type: The KVM device type (see Documentation/virtual/kvm/devices in the
  *        kernel source)
  * @test: If true, only test if device can be created, but don't actually
  *        create the device.
  *
  * Returns: -errno on error, nonnegative on success: @test ? 0 : device fd;
  */
 int kvm_create_device(KVMState *s, uint64_t type, bool test);

 /**
  * kvm_device_supported - probe whether KVM supports specific device
  *
  * @vmfd: The fd handler for VM
  * @type: type of device
  *
  * @return: true if supported, otherwise false.
  */
 bool kvm_device_supported(int vmfd, uint64_t type);

 /* Arch specific hooks */

 extern const KVMCapabilityInfo kvm_arch_required_capabilities[];

 void kvm_arch_pre_run(CPUState *cpu, struct kvm_run *run);
 MemTxAttrs kvm_arch_post_run(CPUState *cpu, struct kvm_run *run);

 int kvm_arch_handle_exit(CPUState *cpu, struct kvm_run *run);

 int kvm_arch_handle_ioapic_eoi(CPUState *cpu, struct kvm_run *run);

 int kvm_arch_process_async_events(CPUState *cpu);

 int kvm_arch_get_registers(CPUState *cpu);

 /* state subset only touched by the VCPU itself during runtime */
 #define KVM_PUT_RUNTIME_STATE   1
 /* state subset modified during VCPU reset */
 #define KVM_PUT_RESET_STATE     2
 /* full state set, modified during initialization or on vmload */
 #define KVM_PUT_FULL_STATE      3

 int kvm_arch_put_registers(CPUState *cpu, int level);

 int kvm_arch_init(MachineState *ms, KVMState *s);

 int kvm_arch_init_vcpu(CPUState *cpu);

 /* Returns VCPU ID to be used on KVM_CREATE_VCPU ioctl() */
 unsigned long kvm_arch_vcpu_id(CPUState *cpu);

 int kvm_arch_on_sigbus_vcpu(CPUState *cpu, int code, void *addr);
 int kvm_arch_on_sigbus(int code, void *addr);

 void kvm_arch_init_irq_routing(KVMState *s);

 int kvm_arch_fixup_msi_route(struct kvm_irq_routing_entry *route,
                              uint64_t address, uint32_t data, PCIDevice *dev);

 int kvm_arch_msi_data_to_gsi(uint32_t data);

 int kvm_set_irq(KVMState *s, int irq, int level);
 int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg);

 void kvm_irqchip_add_irq_route(KVMState *s, int gsi, int irqchip, int pin);
 void kvm_irqchip_commit_routes(KVMState *s);

 void kvm_put_apic_state(DeviceState *d, struct kvm_lapic_state *kapic);
 void kvm_get_apic_state(DeviceState *d, struct kvm_lapic_state *kapic);

 struct kvm_guest_debug;
 struct kvm_debug_exit_arch;

 struct kvm_sw_breakpoint {
     target_ulong pc;
     target_ulong saved_insn;
     int use_count;
     QTAILQ_ENTRY(kvm_sw_breakpoint) entry;
 };

 QTAILQ_HEAD(kvm_sw_breakpoint_head, kvm_sw_breakpoint);

 struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *cpu,
                                                  target_ulong pc);

 int kvm_sw_breakpoints_active(CPUState *cpu);

 int kvm_arch_insert_sw_breakpoint(CPUState *cpu,
                                   struct kvm_sw_breakpoint *bp);
 int kvm_arch_remove_sw_breakpoint(CPUState *cpu,
                                   struct kvm_sw_breakpoint *bp);
 int kvm_arch_insert_hw_breakpoint(target_ulong addr,
                                   target_ulong len, int type);
 int kvm_arch_remove_hw_breakpoint(target_ulong addr,
                                   target_ulong len, int type);
 void kvm_arch_remove_all_hw_breakpoints(void);

 void kvm_arch_update_guest_debug(CPUState *cpu, struct kvm_guest_debug *dbg);

 bool kvm_arch_stop_on_emulation_error(CPUState *cpu);

 int kvm_check_extension(KVMState *s, unsigned int extension);

 int kvm_vm_check_extension(KVMState *s, unsigned int extension);

 #define kvm_vm_enable_cap(s, capability, cap_flags, ...)             \
     ({                                                               \
         struct kvm_enable_cap cap = {                                \
             .cap = capability,                                       \
             .flags = cap_flags,                                      \
         };                                                           \
         uint64_t args_tmp[] = { __VA_ARGS__ };                       \
         int i;                                                       \
         for (i = 0; i < (int)ARRAY_SIZE(args_tmp) &&                 \
                      i < ARRAY_SIZE(cap.args); i++) {                \
             cap.args[i] = args_tmp[i];                               \
         }                                                            \
         kvm_vm_ioctl(s, KVM_ENABLE_CAP, &cap);                       \
     })

 #define kvm_vcpu_enable_cap(cpu, capability, cap_flags, ...)         \
     ({                                                               \
         struct kvm_enable_cap cap = {                                \
             .cap = capability,                                       \
             .flags = cap_flags,                                      \
         };                                                           \
         uint64_t args_tmp[] = { __VA_ARGS__ };                       \
         int i;                                                       \
         for (i = 0; i < (int)ARRAY_SIZE(args_tmp) &&                 \
                      i < ARRAY_SIZE(cap.args); i++) {                \
             cap.args[i] = args_tmp[i];                               \
         }                                                            \
         kvm_vcpu_ioctl(cpu, KVM_ENABLE_CAP, &cap);                   \
     })

 uint32_t kvm_arch_get_supported_cpuid(KVMState *env, uint32_t function,
                                       uint32_t index, int reg);

 void kvm_set_sigmask_len(KVMState *s, unsigned int sigmask_len);

 #if !defined(CONFIG_USER_ONLY)
 int kvm_physical_memory_addr_from_host(KVMState *s, void *ram_addr,
                                        hwaddr *phys_addr);
 #endif

 #endif /* NEED_CPU_H */

 void kvm_cpu_synchronize_state(CPUState *cpu);
 void kvm_cpu_synchronize_post_reset(CPUState *cpu);
 void kvm_cpu_synchronize_post_init(CPUState *cpu);

 /* generic hooks - to be moved/refactored once there are more users */

 static inline void cpu_synchronize_state(CPUState *cpu)
 {
     if (kvm_enabled()) {
         kvm_cpu_synchronize_state(cpu);
     }
 }

 static inline void cpu_synchronize_post_reset(CPUState *cpu)
 {
     if (kvm_enabled()) {
         kvm_cpu_synchronize_post_reset(cpu);
     }
 }

 static inline void cpu_synchronize_post_init(CPUState *cpu)
 {
     if (kvm_enabled()) {
         kvm_cpu_synchronize_post_init(cpu);
     }
 }

 int kvm_irqchip_add_msi_route(KVMState *s, MSIMessage msg, PCIDevice *dev);
 int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg,
                                  PCIDevice *dev);
 void kvm_irqchip_release_virq(KVMState *s, int virq);

 int kvm_irqchip_add_adapter_route(KVMState *s, AdapterInfo *adapter);
 int kvm_irqchip_add_hv_sint_route(KVMState *s, uint32_t vcpu, uint32_t sint);

 int kvm_irqchip_add_irqfd_notifier_gsi(KVMState *s, EventNotifier *n,
                                        EventNotifier *rn, int virq);
 int kvm_irqchip_remove_irqfd_notifier_gsi(KVMState *s, EventNotifier *n,
                                           int virq);
 int kvm_irqchip_add_irqfd_notifier(KVMState *s, EventNotifier *n,
                                    EventNotifier *rn, qemu_irq irq);
 int kvm_irqchip_remove_irqfd_notifier(KVMState *s, EventNotifier *n,
                                       qemu_irq irq);
 void kvm_irqchip_set_qemuirq_gsi(KVMState *s, qemu_irq irq, int gsi);
 void kvm_pc_gsi_handler(void *opaque, int n, int level);
 void kvm_pc_setup_irq_routing(bool pci_enabled);
 void kvm_init_irq_routing(KVMState *s);

 /**
  * kvm_arch_irqchip_create:
  * @KVMState: The KVMState pointer
  * @MachineState: The MachineState pointer
  *
  * Allow architectures to create an in-kernel irq chip themselves.
  *
  * Returns: < 0: error
  *            0: irq chip was not created
  *          > 0: irq chip was created
  */
 int kvm_arch_irqchip_create(MachineState *ms, KVMState *s);

 /**
  * kvm_set_one_reg - set a register value in KVM via KVM_SET_ONE_REG ioctl
  * @id: The register ID
  * @source: The pointer to the value to be set. It must point to a variable
  *          of the correct type/size for the register being accessed.
  *
  * Returns: 0 on success, or a negative errno on failure.
  */
 int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source);

 /**
  * kvm_get_one_reg - get a register value from KVM via KVM_GET_ONE_REG ioctl
  * @id: The register ID
  * @target: The pointer where the value is to be stored. It must point to a
  *          variable of the correct type/size for the register being accessed.
  *
  * Returns: 0 on success, or a negative errno on failure.
  */
 int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target);
 #endif
	/*
	* QEMU KVM support
	*
	* Copyright IBM, Corp. 2008
	*
	* Authors:
	* Anthony Liguori <aliguori@us.ibm.com>
	*
	* This work is licensed under the terms of the GNU GPL, version 2 or later.
	* See the COPYING file in the top-level directory.
	*
	*/

	#ifndef QEMU_KVM_H
	#define QEMU_KVM_H

	#include "qemu/queue.h"
	#include "qom/cpu.h"
	#include "exec/memattrs.h"
	#include "hw/irq.h"

	#ifdef CONFIG_KVM
	#include <linux/kvm.h>
	#include <linux/kvm_para.h>
	#else
	/* These constants must never be used at runtime if kvm_enabled() is false.
	* They exist so we don't need #ifdefs around KVM-specific code that already
	* checks kvm_enabled() properly.
	*/
	#define KVM_CPUID_SIGNATURE 0
	#define KVM_CPUID_FEATURES 0
	#define KVM_FEATURE_CLOCKSOURCE 0
	#define KVM_FEATURE_NOP_IO_DELAY 0
	#define KVM_FEATURE_MMU_OP 0
	#define KVM_FEATURE_CLOCKSOURCE2 0
	#define KVM_FEATURE_ASYNC_PF 0
	#define KVM_FEATURE_STEAL_TIME 0
	#define KVM_FEATURE_PV_EOI 0
	#define KVM_FEATURE_CLOCKSOURCE_STABLE_BIT 0
	#endif

	extern bool kvm_allowed;
	extern bool kvm_kernel_irqchip;
	extern bool kvm_split_irqchip;
	extern bool kvm_async_interrupts_allowed;
	extern bool kvm_halt_in_kernel_allowed;
	extern bool kvm_eventfds_allowed;
	extern bool kvm_irqfds_allowed;
	extern bool kvm_resamplefds_allowed;
	extern bool kvm_msi_via_irqfd_allowed;
	extern bool kvm_gsi_routing_allowed;
	extern bool kvm_gsi_direct_mapping;
	extern bool kvm_readonly_mem_allowed;
	extern bool kvm_direct_msi_allowed;
	extern bool kvm_ioeventfd_any_length_allowed;

	#if defined CONFIG_KVM \|\| !defined NEED_CPU_H
	#define kvm_enabled() (kvm_allowed)
	/**
	* kvm_irqchip_in_kernel:
	*
	* Returns: true if the user asked us to create an in-kernel
	* irqchip via the "kernel_irqchip=on" machine option.
	* What this actually means is architecture and machine model
	* specific: on PC, for instance, it means that the LAPIC,
	* IOAPIC and PIT are all in kernel. This function should never
	* be used from generic target-independent code: use one of the
	* following functions or some other specific check instead.
	*/
	#define kvm_irqchip_in_kernel() (kvm_kernel_irqchip)

	/**
	* kvm_irqchip_is_split:
	*
	* Returns: true if the user asked us to split the irqchip
	* implementation between user and kernel space. The details are
	* architecture and machine specific. On PC, it means that the PIC,
	* IOAPIC, and PIT are in user space while the LAPIC is in the kernel.
	*/
	#define kvm_irqchip_is_split() (kvm_split_irqchip)

	/**
	* kvm_async_interrupts_enabled:
	*
	* Returns: true if we can deliver interrupts to KVM
	* asynchronously (ie by ioctl from any thread at any time)
	* rather than having to do interrupt delivery synchronously
	* (where the vcpu must be stopped at a suitable point first).
	*/
	#define kvm_async_interrupts_enabled() (kvm_async_interrupts_allowed)

	/**
	* kvm_halt_in_kernel
	*
	* Returns: true if halted cpus should still get a KVM_RUN ioctl to run
	* inside of kernel space. This only works if MP state is implemented.
	*/
	#define kvm_halt_in_kernel() (kvm_halt_in_kernel_allowed)

	/**
	* kvm_eventfds_enabled:
	*
	* Returns: true if we can use eventfds to receive notifications
	* from a KVM CPU (ie the kernel supports eventds and we are running
	* with a configuration where it is meaningful to use them).
	*/
	#define kvm_eventfds_enabled() (kvm_eventfds_allowed)

	/**
	* kvm_irqfds_enabled:
	*
	* Returns: true if we can use irqfds to inject interrupts into
	* a KVM CPU (ie the kernel supports irqfds and we are running
	* with a configuration where it is meaningful to use them).
	*/
	#define kvm_irqfds_enabled() (kvm_irqfds_allowed)

	/**
	* kvm_resamplefds_enabled:
	*
	* Returns: true if we can use resamplefds to inject interrupts into
	* a KVM CPU (ie the kernel supports resamplefds and we are running
	* with a configuration where it is meaningful to use them).
	*/
	#define kvm_resamplefds_enabled() (kvm_resamplefds_allowed)

	/**
	* kvm_msi_via_irqfd_enabled:
	*
	* Returns: true if we can route a PCI MSI (Message Signaled Interrupt)
	* to a KVM CPU via an irqfd. This requires that the kernel supports
	* this and that we're running in a configuration that permits it.
	*/
	#define kvm_msi_via_irqfd_enabled() (kvm_msi_via_irqfd_allowed)

	/**
	* kvm_gsi_routing_enabled:
	*
	* Returns: true if GSI routing is enabled (ie the kernel supports
	* it and we're running in a configuration that permits it).
	*/
	#define kvm_gsi_routing_enabled() (kvm_gsi_routing_allowed)

	/**
	* kvm_gsi_direct_mapping:
	*
	* Returns: true if GSI direct mapping is enabled.
	*/
	#define kvm_gsi_direct_mapping() (kvm_gsi_direct_mapping)

	/**
	* kvm_readonly_mem_enabled:
	*
	* Returns: true if KVM readonly memory is enabled (ie the kernel
	* supports it and we're running in a configuration that permits it).
	*/
	#define kvm_readonly_mem_enabled() (kvm_readonly_mem_allowed)

	/**
	* kvm_direct_msi_enabled:
	*
	* Returns: true if KVM allows direct MSI injection.
	*/
	#define kvm_direct_msi_enabled() (kvm_direct_msi_allowed)

	/**
	* kvm_ioeventfd_any_length_enabled:
	* Returns: true if KVM allows any length io eventfd.
	*/
	#define kvm_ioeventfd_any_length_enabled() (kvm_ioeventfd_any_length_allowed)

	#else
	#define kvm_enabled() (0)
	#define kvm_irqchip_in_kernel() (false)
	#define kvm_irqchip_is_split() (false)
	#define kvm_async_interrupts_enabled() (false)
	#define kvm_halt_in_kernel() (false)
	#define kvm_eventfds_enabled() (false)
	#define kvm_irqfds_enabled() (false)
	#define kvm_resamplefds_enabled() (false)
	#define kvm_msi_via_irqfd_enabled() (false)
	#define kvm_gsi_routing_allowed() (false)
	#define kvm_gsi_direct_mapping() (false)
	#define kvm_readonly_mem_enabled() (false)
	#define kvm_direct_msi_enabled() (false)
	#define kvm_ioeventfd_any_length_enabled() (false)
	#endif

	struct kvm_run;
	struct kvm_lapic_state;
	struct kvm_irq_routing_entry;

	typedef struct KVMCapabilityInfo {
	const char *name;
	int value;
	} KVMCapabilityInfo;

	#define KVM_CAP_INFO(CAP) { "KVM_CAP_" stringify(CAP), KVM_CAP_##CAP }
	#define KVM_CAP_LAST_INFO { NULL, 0 }

	struct KVMState;
	typedef struct KVMState KVMState;
	extern KVMState *kvm_state;

	/* external API */

	bool kvm_has_free_slot(MachineState *ms);
	int kvm_has_sync_mmu(void);
	int kvm_has_vcpu_events(void);
	int kvm_has_robust_singlestep(void);
	int kvm_has_debugregs(void);
	int kvm_has_pit_state2(void);
	int kvm_has_many_ioeventfds(void);
	int kvm_has_gsi_routing(void);
	int kvm_has_intx_set_mask(void);

	int kvm_init_vcpu(CPUState *cpu);
	int kvm_cpu_exec(CPUState *cpu);

	#ifdef NEED_CPU_H

	void kvm_setup_guest_memory(void *start, size_t size);
	void kvm_flush_coalesced_mmio_buffer(void);

	int kvm_insert_breakpoint(CPUState *cpu, target_ulong addr,
	target_ulong len, int type);
	int kvm_remove_breakpoint(CPUState *cpu, target_ulong addr,
	target_ulong len, int type);
	void kvm_remove_all_breakpoints(CPUState *cpu);
	int kvm_update_guest_debug(CPUState *cpu, unsigned long reinject_trap);
	#ifndef _WIN32
	int kvm_set_signal_mask(CPUState cpu, const sigset_t sigset);
	#endif

	int kvm_on_sigbus_vcpu(CPUState cpu, int code, void addr);
	int kvm_on_sigbus(int code, void *addr);

	/* interface with exec.c */

	void phys_mem_set_alloc(void (alloc)(size_t, uint64_t *align));

	/* internal API */

	int kvm_ioctl(KVMState *s, int type, ...);

	int kvm_vm_ioctl(KVMState *s, int type, ...);

	int kvm_vcpu_ioctl(CPUState *cpu, int type, ...);

	/**
	* kvm_device_ioctl - call an ioctl on a kvm device
	* @fd: The KVM device file descriptor as returned from KVM_CREATE_DEVICE
	* @type: The device-ctrl ioctl number
	*
	* Returns: -errno on error, nonnegative on success
	*/
	int kvm_device_ioctl(int fd, int type, ...);

	/**
	* kvm_vm_check_attr - check for existence of a specific vm attribute
	* @s: The KVMState pointer
	* @group: the group
	* @attr: the attribute of that group to query for
	*
	* Returns: 1 if the attribute exists
	* 0 if the attribute either does not exist or if the vm device
	* interface is unavailable
	*/
	int kvm_vm_check_attr(KVMState *s, uint32_t group, uint64_t attr);

	/**
	* kvm_device_check_attr - check for existence of a specific device attribute
	* @fd: The device file descriptor
	* @group: the group
	* @attr: the attribute of that group to query for
	*
	* Returns: 1 if the attribute exists
	* 0 if the attribute either does not exist or if the vm device
	* interface is unavailable
	*/
	int kvm_device_check_attr(int fd, uint32_t group, uint64_t attr);

	/**
	* kvm_device_access - set or get value of a specific vm attribute
	* @fd: The device file descriptor
	* @group: the group
	* @attr: the attribute of that group to set or get
	* @val: pointer to a storage area for the value
	* @write: true for set and false for get operation
	*
	* This function is not allowed to fail. Use kvm_device_check_attr()
	* in order to check for the availability of optional attributes.
	*/
	void kvm_device_access(int fd, int group, uint64_t attr,
	void *val, bool write);

	/**
	* kvm_create_device - create a KVM device for the device control API
	* @KVMState: The KVMState pointer
	* @type: The KVM device type (see Documentation/virtual/kvm/devices in the
	* kernel source)
	* @test: If true, only test if device can be created, but don't actually
	* create the device.
	*
	* Returns: -errno on error, nonnegative on success: @test ? 0 : device fd;
	*/
	int kvm_create_device(KVMState *s, uint64_t type, bool test);

	/**
	* kvm_device_supported - probe whether KVM supports specific device
	*
	* @vmfd: The fd handler for VM
	* @type: type of device
	*
	* @return: true if supported, otherwise false.
	*/
	bool kvm_device_supported(int vmfd, uint64_t type);

	/* Arch specific hooks */

	extern const KVMCapabilityInfo kvm_arch_required_capabilities[];

	void kvm_arch_pre_run(CPUState cpu, struct kvm_run run);
	MemTxAttrs kvm_arch_post_run(CPUState cpu, struct kvm_run run);

	int kvm_arch_handle_exit(CPUState cpu, struct kvm_run run);

	int kvm_arch_handle_ioapic_eoi(CPUState cpu, struct kvm_run run);

	int kvm_arch_process_async_events(CPUState *cpu);

	int kvm_arch_get_registers(CPUState *cpu);

	/* state subset only touched by the VCPU itself during runtime */
	#define KVM_PUT_RUNTIME_STATE 1
	/* state subset modified during VCPU reset */
	#define KVM_PUT_RESET_STATE 2
	/* full state set, modified during initialization or on vmload */
	#define KVM_PUT_FULL_STATE 3

	int kvm_arch_put_registers(CPUState *cpu, int level);

	int kvm_arch_init(MachineState ms, KVMState s);

	int kvm_arch_init_vcpu(CPUState *cpu);

	/* Returns VCPU ID to be used on KVM_CREATE_VCPU ioctl() */
	unsigned long kvm_arch_vcpu_id(CPUState *cpu);

	int kvm_arch_on_sigbus_vcpu(CPUState cpu, int code, void addr);
	int kvm_arch_on_sigbus(int code, void *addr);

	void kvm_arch_init_irq_routing(KVMState *s);

	int kvm_arch_fixup_msi_route(struct kvm_irq_routing_entry *route,
	uint64_t address, uint32_t data, PCIDevice *dev);

	int kvm_arch_msi_data_to_gsi(uint32_t data);

	int kvm_set_irq(KVMState *s, int irq, int level);
	int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg);

	void kvm_irqchip_add_irq_route(KVMState *s, int gsi, int irqchip, int pin);
	void kvm_irqchip_commit_routes(KVMState *s);

	void kvm_put_apic_state(DeviceState d, struct kvm_lapic_state kapic);
	void kvm_get_apic_state(DeviceState d, struct kvm_lapic_state kapic);

	struct kvm_guest_debug;
	struct kvm_debug_exit_arch;

	struct kvm_sw_breakpoint {
	target_ulong pc;
	target_ulong saved_insn;
	int use_count;
	QTAILQ_ENTRY(kvm_sw_breakpoint) entry;
	};

	QTAILQ_HEAD(kvm_sw_breakpoint_head, kvm_sw_breakpoint);

	struct kvm_sw_breakpoint kvm_find_sw_breakpoint(CPUState cpu,
	target_ulong pc);

	int kvm_sw_breakpoints_active(CPUState *cpu);

	int kvm_arch_insert_sw_breakpoint(CPUState *cpu,
	struct kvm_sw_breakpoint *bp);
	int kvm_arch_remove_sw_breakpoint(CPUState *cpu,
	struct kvm_sw_breakpoint *bp);
	int kvm_arch_insert_hw_breakpoint(target_ulong addr,
	target_ulong len, int type);
	int kvm_arch_remove_hw_breakpoint(target_ulong addr,
	target_ulong len, int type);
	void kvm_arch_remove_all_hw_breakpoints(void);

	void kvm_arch_update_guest_debug(CPUState cpu, struct kvm_guest_debug dbg);

	bool kvm_arch_stop_on_emulation_error(CPUState *cpu);

	int kvm_check_extension(KVMState *s, unsigned int extension);

	int kvm_vm_check_extension(KVMState *s, unsigned int extension);

	#define kvm_vm_enable_cap(s, capability, cap_flags, ...) \
	({ \
	struct kvm_enable_cap cap = { \
	.cap = capability, \
	.flags = cap_flags, \
	}; \
	uint64_t args_tmp[] = { __VA_ARGS__ }; \
	int i; \
	for (i = 0; i < (int)ARRAY_SIZE(args_tmp) && \
	i < ARRAY_SIZE(cap.args); i++) { \
	cap.args[i] = args_tmp[i]; \
	} \
	kvm_vm_ioctl(s, KVM_ENABLE_CAP, &cap); \
	})

	#define kvm_vcpu_enable_cap(cpu, capability, cap_flags, ...) \
	({ \
	struct kvm_enable_cap cap = { \
	.cap = capability, \
	.flags = cap_flags, \
	}; \
	uint64_t args_tmp[] = { __VA_ARGS__ }; \
	int i; \
	for (i = 0; i < (int)ARRAY_SIZE(args_tmp) && \
	i < ARRAY_SIZE(cap.args); i++) { \
	cap.args[i] = args_tmp[i]; \
	} \
	kvm_vcpu_ioctl(cpu, KVM_ENABLE_CAP, &cap); \
	})

	uint32_t kvm_arch_get_supported_cpuid(KVMState *env, uint32_t function,
	uint32_t index, int reg);

	void kvm_set_sigmask_len(KVMState *s, unsigned int sigmask_len);

	#if !defined(CONFIG_USER_ONLY)
	int kvm_physical_memory_addr_from_host(KVMState s, void ram_addr,
	hwaddr *phys_addr);
	#endif

	#endif /* NEED_CPU_H */

	void kvm_cpu_synchronize_state(CPUState *cpu);
	void kvm_cpu_synchronize_post_reset(CPUState *cpu);
	void kvm_cpu_synchronize_post_init(CPUState *cpu);

	/* generic hooks - to be moved/refactored once there are more users */

	static inline void cpu_synchronize_state(CPUState *cpu)
	{
	if (kvm_enabled()) {
	kvm_cpu_synchronize_state(cpu);
	}
	}

	static inline void cpu_synchronize_post_reset(CPUState *cpu)
	{
	if (kvm_enabled()) {
	kvm_cpu_synchronize_post_reset(cpu);
	}
	}

	static inline void cpu_synchronize_post_init(CPUState *cpu)
	{
	if (kvm_enabled()) {
	kvm_cpu_synchronize_post_init(cpu);
	}
	}

	int kvm_irqchip_add_msi_route(KVMState s, MSIMessage msg, PCIDevice dev);
	int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg,
	PCIDevice *dev);
	void kvm_irqchip_release_virq(KVMState *s, int virq);

	int kvm_irqchip_add_adapter_route(KVMState s, AdapterInfo adapter);
	int kvm_irqchip_add_hv_sint_route(KVMState *s, uint32_t vcpu, uint32_t sint);

	int kvm_irqchip_add_irqfd_notifier_gsi(KVMState s, EventNotifier n,
	EventNotifier *rn, int virq);
	int kvm_irqchip_remove_irqfd_notifier_gsi(KVMState s, EventNotifier n,
	int virq);
	int kvm_irqchip_add_irqfd_notifier(KVMState s, EventNotifier n,
	EventNotifier *rn, qemu_irq irq);
	int kvm_irqchip_remove_irqfd_notifier(KVMState s, EventNotifier n,
	qemu_irq irq);
	void kvm_irqchip_set_qemuirq_gsi(KVMState *s, qemu_irq irq, int gsi);
	void kvm_pc_gsi_handler(void *opaque, int n, int level);
	void kvm_pc_setup_irq_routing(bool pci_enabled);
	void kvm_init_irq_routing(KVMState *s);

	/**
	* kvm_arch_irqchip_create:
	* @KVMState: The KVMState pointer
	* @MachineState: The MachineState pointer
	*
	* Allow architectures to create an in-kernel irq chip themselves.
	*
	* Returns: < 0: error
	* 0: irq chip was not created
	* > 0: irq chip was created
	*/
	int kvm_arch_irqchip_create(MachineState ms, KVMState s);

	/**
	* kvm_set_one_reg - set a register value in KVM via KVM_SET_ONE_REG ioctl
	* @id: The register ID
	* @source: The pointer to the value to be set. It must point to a variable
	* of the correct type/size for the register being accessed.
	*
	* Returns: 0 on success, or a negative errno on failure.
	*/
	int kvm_set_one_reg(CPUState cs, uint64_t id, void source);

	/**
	* kvm_get_one_reg - get a register value from KVM via KVM_GET_ONE_REG ioctl
	* @id: The register ID
	* @target: The pointer where the value is to be stored. It must point to a
	* variable of the correct type/size for the register being accessed.
	*
	* Returns: 0 on success, or a negative errno on failure.
	*/
	int kvm_get_one_reg(CPUState cs, uint64_t id, void target);
	#endif