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Diffstat (limited to 'Documentation/virtual/kvm/api.txt')
| -rw-r--r-- | Documentation/virtual/kvm/api.txt | 1110 |
1 files changed, 1057 insertions, 53 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 6386f8c0482..0fe36497642 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -2,6 +2,7 @@ The Definitive KVM (Kernel-based Virtual Machine) API Documentation =================================================================== 1. General description +---------------------- The kvm API is a set of ioctls that are issued to control various aspects of a virtual machine. The ioctls belong to three classes @@ -23,7 +24,9 @@ of a virtual machine. The ioctls belong to three classes Only run vcpu ioctls from the same thread that was used to create the vcpu. + 2. File descriptors +------------------- The kvm API is centered around file descriptors. An initial open("/dev/kvm") obtains a handle to the kvm subsystem; this handle @@ -41,19 +44,23 @@ not cause harm to the host, their actual behavior is not guaranteed by the API. The only supported use is one virtual machine per process, and one vcpu per thread. + 3. Extensions +------------- As of Linux 2.6.22, the KVM ABI has been stabilized: no backward incompatible change are allowed. However, there is an extension facility that allows backward-compatible extensions to the API to be queried and used. -The extension mechanism is not based on on the Linux version number. +The extension mechanism is not based on the Linux version number. Instead, kvm defines extension identifiers and a facility to query whether a particular extension identifier is available. If it is, a set of ioctls is available for application use. + 4. API description +------------------ This section describes ioctls that can be used to control kvm guests. For each ioctl, the following information is provided along with a @@ -75,6 +82,7 @@ description: Returns: the return value. General error numbers (EBADF, ENOMEM, EINVAL) are not detailed, but errors with specific meanings are. + 4.1 KVM_GET_API_VERSION Capability: basic @@ -90,6 +98,7 @@ supported. Applications should refuse to run if KVM_GET_API_VERSION returns a value other than 12. If this check passes, all ioctls described as 'basic' will be available. + 4.2 KVM_CREATE_VM Capability: basic @@ -109,6 +118,7 @@ In order to create user controlled virtual machines on S390, check KVM_CAP_S390_UCONTROL and use the flag KVM_VM_S390_UCONTROL as privileged user (CAP_SYS_ADMIN). + 4.3 KVM_GET_MSR_INDEX_LIST Capability: basic @@ -135,6 +145,7 @@ Note: if kvm indicates supports MCE (KVM_CAP_MCE), then the MCE bank MSRs are not returned in the MSR list, as different vcpus can have a different number of banks, as set via the KVM_X86_SETUP_MCE ioctl. + 4.4 KVM_CHECK_EXTENSION Capability: basic @@ -149,6 +160,7 @@ receives an integer that describes the extension availability. Generally 0 means no and 1 means yes, but some extensions may report additional information in the integer return value. + 4.5 KVM_GET_VCPU_MMAP_SIZE Capability: basic @@ -161,6 +173,7 @@ The KVM_RUN ioctl (cf.) communicates with userspace via a shared memory region. This ioctl returns the size of that region. See the KVM_RUN documentation for details. + 4.6 KVM_SET_MEMORY_REGION Capability: basic @@ -171,6 +184,7 @@ Returns: 0 on success, -1 on error This ioctl is obsolete and has been removed. + 4.7 KVM_CREATE_VCPU Capability: basic @@ -205,24 +219,12 @@ allocation of vcpu ids. For example, if userspace wants single-threaded guest vcpus, it should make all vcpu ids be a multiple of the number of vcpus per vcore. -On powerpc using book3s_hv mode, the vcpus are mapped onto virtual -threads in one or more virtual CPU cores. (This is because the -hardware requires all the hardware threads in a CPU core to be in the -same partition.) The KVM_CAP_PPC_SMT capability indicates the number -of vcpus per virtual core (vcore). The vcore id is obtained by -dividing the vcpu id by the number of vcpus per vcore. The vcpus in a -given vcore will always be in the same physical core as each other -(though that might be a different physical core from time to time). -Userspace can control the threading (SMT) mode of the guest by its -allocation of vcpu ids. For example, if userspace wants -single-threaded guest vcpus, it should make all vcpu ids be a multiple -of the number of vcpus per vcore. - For virtual cpus that have been created with S390 user controlled virtual machines, the resulting vcpu fd can be memory mapped at page offset KVM_S390_SIE_PAGE_OFFSET in order to obtain a memory map of the virtual cpu's hardware control block. + 4.8 KVM_GET_DIRTY_LOG (vm ioctl) Capability: basic @@ -246,6 +248,7 @@ since the last call to this ioctl. Bit 0 is the first page in the memory slot. Ensure the entire structure is cleared to avoid padding issues. + 4.9 KVM_SET_MEMORY_ALIAS Capability: basic @@ -256,6 +259,7 @@ Returns: 0 (success), -1 (error) This ioctl is obsolete and has been removed. + 4.10 KVM_RUN Capability: basic @@ -272,10 +276,11 @@ obtained by mmap()ing the vcpu fd at offset 0, with the size given by KVM_GET_VCPU_MMAP_SIZE. The parameter block is formatted as a 'struct kvm_run' (see below). + 4.11 KVM_GET_REGS Capability: basic -Architectures: all +Architectures: all except ARM, arm64 Type: vcpu ioctl Parameters: struct kvm_regs (out) Returns: 0 on success, -1 on error @@ -292,10 +297,11 @@ struct kvm_regs { __u64 rip, rflags; }; + 4.12 KVM_SET_REGS Capability: basic -Architectures: all +Architectures: all except ARM, arm64 Type: vcpu ioctl Parameters: struct kvm_regs (in) Returns: 0 on success, -1 on error @@ -304,6 +310,7 @@ Writes the general purpose registers into the vcpu. See KVM_GET_REGS for the data structure. + 4.13 KVM_GET_SREGS Capability: basic @@ -325,12 +332,13 @@ struct kvm_sregs { __u64 interrupt_bitmap[(KVM_NR_INTERRUPTS + 63) / 64]; }; -/* ppc -- see arch/powerpc/include/asm/kvm.h */ +/* ppc -- see arch/powerpc/include/uapi/asm/kvm.h */ interrupt_bitmap is a bitmap of pending external interrupts. At most one bit may be set. This interrupt has been acknowledged by the APIC but not yet injected into the cpu core. + 4.14 KVM_SET_SREGS Capability: basic @@ -342,6 +350,7 @@ Returns: 0 on success, -1 on error Writes special registers into the vcpu. See KVM_GET_SREGS for the data structures. + 4.15 KVM_TRANSLATE Capability: basic @@ -365,6 +374,7 @@ struct kvm_translation { __u8 pad[5]; }; + 4.16 KVM_INTERRUPT Capability: basic @@ -413,6 +423,7 @@ c) KVM_INTERRUPT_SET_LEVEL Note that any value for 'irq' other than the ones stated above is invalid and incurs unexpected behavior. + 4.17 KVM_DEBUG_GUEST Capability: basic @@ -423,6 +434,7 @@ Returns: -1 on error Support for this has been removed. Use KVM_SET_GUEST_DEBUG instead. + 4.18 KVM_GET_MSRS Capability: basic @@ -451,6 +463,7 @@ Application code should set the 'nmsrs' member (which indicates the size of the entries array) and the 'index' member of each array entry. kvm will fill in the 'data' member. + 4.19 KVM_SET_MSRS Capability: basic @@ -466,6 +479,7 @@ Application code should set the 'nmsrs' member (which indicates the size of the entries array), and the 'index' and 'data' members of each array entry. + 4.20 KVM_SET_CPUID Capability: basic @@ -494,6 +508,7 @@ struct kvm_cpuid { struct kvm_cpuid_entry entries[0]; }; + 4.21 KVM_SET_SIGNAL_MASK Capability: basic @@ -516,6 +531,7 @@ struct kvm_signal_mask { __u8 sigset[0]; }; + 4.22 KVM_GET_FPU Capability: basic @@ -541,6 +557,7 @@ struct kvm_fpu { __u32 pad2; }; + 4.23 KVM_SET_FPU Capability: basic @@ -566,10 +583,11 @@ struct kvm_fpu { __u32 pad2; }; + 4.24 KVM_CREATE_IRQCHIP -Capability: KVM_CAP_IRQCHIP -Architectures: x86, ia64 +Capability: KVM_CAP_IRQCHIP, KVM_CAP_S390_IRQCHIP (s390) +Architectures: x86, ia64, ARM, arm64, s390 Type: vm ioctl Parameters: none Returns: 0 on success, -1 on error @@ -577,20 +595,57 @@ Returns: 0 on success, -1 on error 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. +only go to the IOAPIC. On ia64, a IOSAPIC is created. On ARM/arm64, a GIC is +created. On s390, a dummy irq routing table is created. + +Note that on s390 the KVM_CAP_S390_IRQCHIP vm capability needs to be enabled +before KVM_CREATE_IRQCHIP can be used. + 4.25 KVM_IRQ_LINE Capability: KVM_CAP_IRQCHIP -Architectures: x86, ia64 +Architectures: x86, ia64, arm, arm64 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. +On some architectures it is required 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. + +On real hardware, interrupt pins can be active-low or active-high. This +does not matter for the level field of struct kvm_irq_level: 1 always +means active (asserted), 0 means inactive (deasserted). + +x86 allows the operating system to program the interrupt polarity +(active-low/active-high) for level-triggered interrupts, and KVM used +to consider the polarity. However, due to bitrot in the handling of +active-low interrupts, the above convention is now valid on x86 too. +This is signaled by KVM_CAP_X86_IOAPIC_POLARITY_IGNORED. Userspace +should not present interrupts to the guest as active-low unless this +capability is present (or unless it is not using the in-kernel irqchip, +of course). + + +ARM/arm64 can signal an interrupt either at the CPU level, or at the +in-kernel irqchip (GIC), and for in-kernel irqchip can tell the GIC to +use PPIs designated for specific cpus. The irq field is interpreted +like this: + + bits: | 31 ... 24 | 23 ... 16 | 15 ... 0 | + field: | irq_type | vcpu_index | irq_id | + +The irq_type field has the following values: +- irq_type[0]: out-of-kernel GIC: irq_id 0 is IRQ, irq_id 1 is FIQ +- irq_type[1]: in-kernel GIC: SPI, irq_id between 32 and 1019 (incl.) + (the vcpu_index field is ignored) +- irq_type[2]: in-kernel GIC: PPI, irq_id between 16 and 31 (incl.) + +(The irq_id field thus corresponds nicely to the IRQ ID in the ARM GIC specs) + +In both cases, level is used to assert/deassert the line. struct kvm_irq_level { union { @@ -600,6 +655,7 @@ struct kvm_irq_level { __u32 level; /* 0 or 1 */ }; + 4.26 KVM_GET_IRQCHIP Capability: KVM_CAP_IRQCHIP @@ -621,6 +677,7 @@ struct kvm_irqchip { } chip; }; + 4.27 KVM_SET_IRQCHIP Capability: KVM_CAP_IRQCHIP @@ -642,6 +699,7 @@ struct kvm_irqchip { } chip; }; + 4.28 KVM_XEN_HVM_CONFIG Capability: KVM_CAP_XEN_HVM @@ -666,6 +724,7 @@ struct kvm_xen_hvm_config { __u8 pad2[30]; }; + 4.29 KVM_GET_CLOCK Capability: KVM_CAP_ADJUST_CLOCK @@ -684,6 +743,7 @@ struct kvm_clock_data { __u32 pad[9]; }; + 4.30 KVM_SET_CLOCK Capability: KVM_CAP_ADJUST_CLOCK @@ -702,6 +762,7 @@ struct kvm_clock_data { __u32 pad[9]; }; + 4.31 KVM_GET_VCPU_EVENTS Capability: KVM_CAP_VCPU_EVENTS @@ -741,6 +802,7 @@ struct kvm_vcpu_events { KVM_VCPUEVENT_VALID_SHADOW may be set in the flags field to signal that interrupt.shadow contains a valid state. Otherwise, this field is undefined. + 4.32 KVM_SET_VCPU_EVENTS Capability: KVM_CAP_VCPU_EVENTS @@ -767,6 +829,7 @@ If KVM_CAP_INTR_SHADOW is available, KVM_VCPUEVENT_VALID_SHADOW can be set in the flags field to signal that interrupt.shadow contains a valid state and shall be written into the VCPU. + 4.33 KVM_GET_DEBUGREGS Capability: KVM_CAP_DEBUGREGS @@ -785,6 +848,7 @@ struct kvm_debugregs { __u64 reserved[9]; }; + 4.34 KVM_SET_DEBUGREGS Capability: KVM_CAP_DEBUGREGS @@ -798,6 +862,7 @@ Writes debug registers into the vcpu. See KVM_GET_DEBUGREGS for the data structure. The flags field is unused yet and must be cleared on entry. + 4.35 KVM_SET_USER_MEMORY_REGION Capability: KVM_CAP_USER_MEM @@ -815,7 +880,8 @@ struct kvm_userspace_memory_region { }; /* for kvm_memory_region::flags */ -#define KVM_MEM_LOG_DIRTY_PAGES 1UL +#define KVM_MEM_LOG_DIRTY_PAGES (1UL << 0) +#define KVM_MEM_READONLY (1UL << 1) This ioctl allows the user to create or modify a guest physical memory slot. When changing an existing slot, it may be moved in the guest @@ -831,19 +897,23 @@ It is recommended that the lower 21 bits of guest_phys_addr and userspace_addr be identical. This allows large pages in the guest to be backed by large pages in the host. -The flags field supports just one flag, KVM_MEM_LOG_DIRTY_PAGES, which -instructs kvm to keep track of writes to memory within the slot. See -the KVM_GET_DIRTY_LOG ioctl. +The flags field supports two flags: KVM_MEM_LOG_DIRTY_PAGES and +KVM_MEM_READONLY. The former can be set to instruct KVM to keep track of +writes to memory within the slot. See KVM_GET_DIRTY_LOG ioctl to know how to +use it. The latter can be set, if KVM_CAP_READONLY_MEM capability allows it, +to make a new slot read-only. In this case, writes to this memory will be +posted to userspace as KVM_EXIT_MMIO exits. -When the KVM_CAP_SYNC_MMU capability, changes in the backing of the memory -region are automatically reflected into the guest. For example, an mmap() -that affects the region will be made visible immediately. Another example -is madvise(MADV_DROP). +When the KVM_CAP_SYNC_MMU capability is available, changes in the backing of +the memory region are automatically reflected into the guest. For example, an +mmap() that affects the region will be made visible immediately. Another +example is madvise(MADV_DROP). It is recommended to use this API instead of the KVM_SET_MEMORY_REGION ioctl. The KVM_SET_MEMORY_REGION does not allow fine grained control over memory allocation and is deprecated. + 4.36 KVM_SET_TSS_ADDR Capability: KVM_CAP_SET_TSS_ADDR @@ -862,11 +932,12 @@ This ioctl is required on Intel-based hosts. This is needed on Intel hardware because of a quirk in the virtualization implementation (see the internals documentation when it pops into existence). + 4.37 KVM_ENABLE_CAP -Capability: KVM_CAP_ENABLE_CAP -Architectures: ppc -Type: vcpu ioctl +Capability: KVM_CAP_ENABLE_CAP, KVM_CAP_ENABLE_CAP_VM +Architectures: ppc, s390 +Type: vcpu ioctl, vm ioctl (with KVM_CAP_ENABLE_CAP_VM) Parameters: struct kvm_enable_cap (in) Returns: 0 on success; -1 on error @@ -897,6 +968,9 @@ function properly, this is the place to put them. __u8 pad[64]; }; +The vcpu ioctl should be used for vcpu-specific capabilities, the vm ioctl +for vm-wide capabilities. + 4.38 KVM_GET_MP_STATE Capability: KVM_CAP_MP_STATE @@ -927,6 +1001,7 @@ Possible values are: This ioctl is only useful after KVM_CREATE_IRQCHIP. Without an in-kernel irqchip, the multiprocessing state must be maintained by userspace. + 4.39 KVM_SET_MP_STATE Capability: KVM_CAP_MP_STATE @@ -941,6 +1016,7 @@ arguments. This ioctl is only useful after KVM_CREATE_IRQCHIP. Without an in-kernel irqchip, the multiprocessing state must be maintained by userspace. + 4.40 KVM_SET_IDENTITY_MAP_ADDR Capability: KVM_CAP_SET_IDENTITY_MAP_ADDR @@ -959,6 +1035,7 @@ This ioctl is required on Intel-based hosts. This is needed on Intel hardware because of a quirk in the virtualization implementation (see the internals documentation when it pops into existence). + 4.41 KVM_SET_BOOT_CPU_ID Capability: KVM_CAP_SET_BOOT_CPU_ID @@ -971,6 +1048,7 @@ Define which vcpu is the Bootstrap Processor (BSP). Values are the same as the vcpu id in KVM_CREATE_VCPU. If this ioctl is not called, the default is vcpu 0. + 4.42 KVM_GET_XSAVE Capability: KVM_CAP_XSAVE @@ -985,6 +1063,7 @@ struct kvm_xsave { This ioctl would copy current vcpu's xsave struct to the userspace. + 4.43 KVM_SET_XSAVE Capability: KVM_CAP_XSAVE @@ -999,6 +1078,7 @@ struct kvm_xsave { This ioctl would copy userspace's xsave struct to the kernel. + 4.44 KVM_GET_XCRS Capability: KVM_CAP_XCRS @@ -1022,6 +1102,7 @@ struct kvm_xcrs { This ioctl would copy current vcpu's xcrs to the userspace. + 4.45 KVM_SET_XCRS Capability: KVM_CAP_XCRS @@ -1045,6 +1126,7 @@ struct kvm_xcrs { This ioctl would set vcpu's xcr to the value userspace specified. + 4.46 KVM_GET_SUPPORTED_CPUID Capability: KVM_CAP_EXT_CPUID @@ -1059,9 +1141,9 @@ struct kvm_cpuid2 { struct kvm_cpuid_entry2 entries[0]; }; -#define KVM_CPUID_FLAG_SIGNIFCANT_INDEX 1 -#define KVM_CPUID_FLAG_STATEFUL_FUNC 2 -#define KVM_CPUID_FLAG_STATE_READ_NEXT 4 +#define KVM_CPUID_FLAG_SIGNIFCANT_INDEX BIT(0) +#define KVM_CPUID_FLAG_STATEFUL_FUNC BIT(1) +#define KVM_CPUID_FLAG_STATE_READ_NEXT BIT(2) struct kvm_cpuid_entry2 { __u32 function; @@ -1119,6 +1201,7 @@ support. Instead it is reported via if that returns true and you use KVM_CREATE_IRQCHIP, or if you emulate the feature in userspace, then you can enable the feature for KVM_SET_CPUID2. + 4.47 KVM_PPC_GET_PVINFO Capability: KVM_CAP_PPC_GET_PVINFO @@ -1136,12 +1219,16 @@ struct kvm_ppc_pvinfo { This ioctl fetches PV specific information that need to be passed to the guest using the device tree or other means from vm context. -For now the only implemented piece of information distributed here is an array -of 4 instructions that make up a hypercall. +The hcall array defines 4 instructions that make up a hypercall. If any additional field gets added to this structure later on, a bit for that additional piece of information will be set in the flags bitmap. +The flags bitmap is defined as: + + /* the host supports the ePAPR idle hcall + #define KVM_PPC_PVINFO_FLAGS_EV_IDLE (1<<0) + 4.48 KVM_ASSIGN_PCI_DEVICE Capability: KVM_CAP_DEVICE_ASSIGNMENT @@ -1185,6 +1272,7 @@ Only PCI header type 0 devices with PCI BAR resources are supported by device assignment. The user requesting this ioctl must have read/write access to the PCI sysfs resource files associated with the device. + 4.49 KVM_DEASSIGN_PCI_DEVICE Capability: KVM_CAP_DEVICE_DEASSIGNMENT @@ -1198,6 +1286,7 @@ Ends PCI device assignment, releasing all associated resources. See KVM_CAP_DEVICE_ASSIGNMENT for the data structure. Only assigned_dev_id is used in kvm_assigned_pci_dev to identify the device. + 4.50 KVM_ASSIGN_DEV_IRQ Capability: KVM_CAP_ASSIGN_DEV_IRQ @@ -1231,6 +1320,7 @@ The following flags are defined: It is not valid to specify multiple types per host or guest IRQ. However, the IRQ type of host and guest can differ or can even be null. + 4.51 KVM_DEASSIGN_DEV_IRQ Capability: KVM_CAP_ASSIGN_DEV_IRQ @@ -1245,10 +1335,11 @@ See KVM_ASSIGN_DEV_IRQ for the data structure. The target device is specified by assigned_dev_id, flags must correspond to the IRQ type specified on KVM_ASSIGN_DEV_IRQ. Partial deassignment of host or guest IRQ is allowed. + 4.52 KVM_SET_GSI_ROUTING Capability: KVM_CAP_IRQ_ROUTING -Architectures: x86 ia64 +Architectures: x86 ia64 s390 Type: vm ioctl Parameters: struct kvm_irq_routing (in) Returns: 0 on success, -1 on error @@ -1271,6 +1362,7 @@ struct kvm_irq_routing_entry { union { struct kvm_irq_routing_irqchip irqchip; struct kvm_irq_routing_msi msi; + struct kvm_irq_routing_s390_adapter adapter; __u32 pad[8]; } u; }; @@ -1278,6 +1370,7 @@ struct kvm_irq_routing_entry { /* gsi routing entry types */ #define KVM_IRQ_ROUTING_IRQCHIP 1 #define KVM_IRQ_ROUTING_MSI 2 +#define KVM_IRQ_ROUTING_S390_ADAPTER 3 No flags are specified so far, the corresponding field must be set to zero. @@ -1293,6 +1386,15 @@ struct kvm_irq_routing_msi { __u32 pad; }; +struct kvm_irq_routing_s390_adapter { + __u64 ind_addr; + __u64 summary_addr; + __u64 ind_offset; + __u32 summary_offset; + __u32 adapter_id; +}; + + 4.53 KVM_ASSIGN_SET_MSIX_NR Capability: KVM_CAP_DEVICE_MSIX @@ -1314,6 +1416,7 @@ struct kvm_assigned_msix_nr { #define KVM_MAX_MSIX_PER_DEV 256 + 4.54 KVM_ASSIGN_SET_MSIX_ENTRY Capability: KVM_CAP_DEVICE_MSIX @@ -1332,7 +1435,8 @@ struct kvm_assigned_msix_entry { __u16 padding[3]; }; -4.54 KVM_SET_TSC_KHZ + +4.55 KVM_SET_TSC_KHZ Capability: KVM_CAP_TSC_CONTROL Architectures: x86 @@ -1343,7 +1447,8 @@ Returns: 0 on success, -1 on error Specifies the tsc frequency for the virtual machine. The unit of the frequency is KHz. -4.55 KVM_GET_TSC_KHZ + +4.56 KVM_GET_TSC_KHZ Capability: KVM_CAP_GET_TSC_KHZ Architectures: x86 @@ -1355,7 +1460,8 @@ Returns the tsc frequency of the guest. The unit of the return value is KHz. If the host has unstable tsc this ioctl returns -EIO instead as an error. -4.56 KVM_GET_LAPIC + +4.57 KVM_GET_LAPIC Capability: KVM_CAP_IRQCHIP Architectures: x86 @@ -1371,7 +1477,8 @@ struct kvm_lapic_state { Reads the Local APIC registers and copies them into the input argument. The data format and layout are the same as documented in the architecture manual. -4.57 KVM_SET_LAPIC + +4.58 KVM_SET_LAPIC Capability: KVM_CAP_IRQCHIP Architectures: x86 @@ -1384,10 +1491,11 @@ struct kvm_lapic_state { char regs[KVM_APIC_REG_SIZE]; }; -Copies the input argument into the the Local APIC registers. The data format +Copies the input argument into the Local APIC registers. The data format and layout are the same as documented in the architecture manual. -4.58 KVM_IOEVENTFD + +4.59 KVM_IOEVENTFD Capability: KVM_CAP_IOEVENTFD Architectures: all @@ -1408,16 +1516,25 @@ struct kvm_ioeventfd { __u8 pad[36]; }; +For the special case of virtio-ccw devices on s390, the ioevent is matched +to a subchannel/virtqueue tuple instead. + The following flags are defined: #define KVM_IOEVENTFD_FLAG_DATAMATCH (1 << kvm_ioeventfd_flag_nr_datamatch) #define KVM_IOEVENTFD_FLAG_PIO (1 << kvm_ioeventfd_flag_nr_pio) #define KVM_IOEVENTFD_FLAG_DEASSIGN (1 << kvm_ioeventfd_flag_nr_deassign) +#define KVM_IOEVENTFD_FLAG_VIRTIO_CCW_NOTIFY \ + (1 << kvm_ioeventfd_flag_nr_virtio_ccw_notify) If datamatch flag is set, the event will be signaled only if the written value to the registered address is equal to datamatch in struct kvm_ioeventfd. -4.59 KVM_DIRTY_TLB +For virtio-ccw devices, addr contains the subchannel id and datamatch the +virtqueue index. + + +4.60 KVM_DIRTY_TLB Capability: KVM_CAP_SW_TLB Architectures: ppc @@ -1449,7 +1566,8 @@ The "num_dirty" field is a performance hint for KVM to determine whether it should skip processing the bitmap and just invalidate everything. It must be set to the number of set bits in the bitmap. -4.60 KVM_ASSIGN_SET_INTX_MASK + +4.61 KVM_ASSIGN_SET_INTX_MASK Capability: KVM_CAP_PCI_2_3 Architectures: x86 @@ -1482,6 +1600,7 @@ See KVM_ASSIGN_DEV_IRQ for the data structure. The target device is specified by assigned_dev_id. In the flags field, only KVM_DEV_ASSIGN_MASK_INTX is evaluated. + 4.62 KVM_CREATE_SPAPR_TCE Capability: KVM_CAP_SPAPR_TCE @@ -1517,6 +1636,7 @@ the entries written by kernel-handled H_PUT_TCE calls, and also lets userspace update the TCE table directly which is useful in some circumstances. + 4.63 KVM_ALLOCATE_RMA Capability: KVM_CAP_PPC_RMA @@ -1549,6 +1669,7 @@ is supported; 2 if the processor requires all virtual machines to have an RMA, or 1 if the processor can use an RMA but doesn't require it, because it supports the Virtual RMA (VRMA) facility. + 4.64 KVM_NMI Capability: KVM_CAP_USER_NMI @@ -1574,6 +1695,7 @@ following algorithm: Some guests configure the LINT1 NMI input to cause a panic, aiding in debugging. + 4.65 KVM_S390_UCAS_MAP Capability: KVM_CAP_S390_UCONTROL @@ -1591,7 +1713,8 @@ The parameter is defined like this: This ioctl maps the memory at "user_addr" with the length "length" to the vcpu's address space starting at "vcpu_addr". All parameters need to -be alligned by 1 megabyte. +be aligned by 1 megabyte. + 4.66 KVM_S390_UCAS_UNMAP @@ -1610,7 +1733,8 @@ The parameter is defined like this: This ioctl unmaps the memory in the vcpu's address space starting at "vcpu_addr" with the length "length". The field "user_addr" is ignored. -All parameters need to be alligned by 1 megabyte. +All parameters need to be aligned by 1 megabyte. + 4.67 KVM_S390_VCPU_FAULT @@ -1628,6 +1752,7 @@ table upfront. This is useful to handle validity intercepts for user controlled virtual machines to fault in the virtual cpu's lowcore pages prior to calling the KVM_RUN ioctl. + 4.68 KVM_SET_ONE_REG Capability: KVM_CAP_ONE_REG @@ -1652,6 +1777,156 @@ registers, find a list below: Arch | Register | Width (bits) | | PPC | KVM_REG_PPC_HIOR | 64 + PPC | KVM_REG_PPC_IAC1 | 64 + PPC | KVM_REG_PPC_IAC2 | 64 + PPC | KVM_REG_PPC_IAC3 | 64 + PPC | KVM_REG_PPC_IAC4 | 64 + PPC | KVM_REG_PPC_DAC1 | 64 + PPC | KVM_REG_PPC_DAC2 | 64 + PPC | KVM_REG_PPC_DABR | 64 + PPC | KVM_REG_PPC_DSCR | 64 + PPC | KVM_REG_PPC_PURR | 64 + PPC | KVM_REG_PPC_SPURR | 64 + PPC | KVM_REG_PPC_DAR | 64 + PPC | KVM_REG_PPC_DSISR | 32 + PPC | KVM_REG_PPC_AMR | 64 + PPC | KVM_REG_PPC_UAMOR | 64 + PPC | KVM_REG_PPC_MMCR0 | 64 + PPC | KVM_REG_PPC_MMCR1 | 64 + PPC | KVM_REG_PPC_MMCRA | 64 + PPC | KVM_REG_PPC_MMCR2 | 64 + PPC | KVM_REG_PPC_MMCRS | 64 + PPC | KVM_REG_PPC_SIAR | 64 + PPC | KVM_REG_PPC_SDAR | 64 + PPC | KVM_REG_PPC_SIER | 64 + PPC | KVM_REG_PPC_PMC1 | 32 + PPC | KVM_REG_PPC_PMC2 | 32 + PPC | KVM_REG_PPC_PMC3 | 32 + PPC | KVM_REG_PPC_PMC4 | 32 + PPC | KVM_REG_PPC_PMC5 | 32 + PPC | KVM_REG_PPC_PMC6 | 32 + PPC | KVM_REG_PPC_PMC7 | 32 + PPC | KVM_REG_PPC_PMC8 | 32 + PPC | KVM_REG_PPC_FPR0 | 64 + ... + PPC | KVM_REG_PPC_FPR31 | 64 + PPC | KVM_REG_PPC_VR0 | 128 + ... + PPC | KVM_REG_PPC_VR31 | 128 + PPC | KVM_REG_PPC_VSR0 | 128 + ... + PPC | KVM_REG_PPC_VSR31 | 128 + PPC | KVM_REG_PPC_FPSCR | 64 + PPC | KVM_REG_PPC_VSCR | 32 + PPC | KVM_REG_PPC_VPA_ADDR | 64 + PPC | KVM_REG_PPC_VPA_SLB | 128 + PPC | KVM_REG_PPC_VPA_DTL | 128 + PPC | KVM_REG_PPC_EPCR | 32 + PPC | KVM_REG_PPC_EPR | 32 + PPC | KVM_REG_PPC_TCR | 32 + PPC | KVM_REG_PPC_TSR | 32 + PPC | KVM_REG_PPC_OR_TSR | 32 + PPC | KVM_REG_PPC_CLEAR_TSR | 32 + PPC | KVM_REG_PPC_MAS0 | 32 + PPC | KVM_REG_PPC_MAS1 | 32 + PPC | KVM_REG_PPC_MAS2 | 64 + PPC | KVM_REG_PPC_MAS7_3 | 64 + PPC | KVM_REG_PPC_MAS4 | 32 + PPC | KVM_REG_PPC_MAS6 | 32 + PPC | KVM_REG_PPC_MMUCFG | 32 + PPC | KVM_REG_PPC_TLB0CFG | 32 + PPC | KVM_REG_PPC_TLB1CFG | 32 + PPC | KVM_REG_PPC_TLB2CFG | 32 + PPC | KVM_REG_PPC_TLB3CFG | 32 + PPC | KVM_REG_PPC_TLB0PS | 32 + PPC | KVM_REG_PPC_TLB1PS | 32 + PPC | KVM_REG_PPC_TLB2PS | 32 + PPC | KVM_REG_PPC_TLB3PS | 32 + PPC | KVM_REG_PPC_EPTCFG | 32 + PPC | KVM_REG_PPC_ICP_STATE | 64 + PPC | KVM_REG_PPC_TB_OFFSET | 64 + PPC | KVM_REG_PPC_SPMC1 | 32 + PPC | KVM_REG_PPC_SPMC2 | 32 + PPC | KVM_REG_PPC_IAMR | 64 + PPC | KVM_REG_PPC_TFHAR | 64 + PPC | KVM_REG_PPC_TFIAR | 64 + PPC | KVM_REG_PPC_TEXASR | 64 + PPC | KVM_REG_PPC_FSCR | 64 + PPC | KVM_REG_PPC_PSPB | 32 + PPC | KVM_REG_PPC_EBBHR | 64 + PPC | KVM_REG_PPC_EBBRR | 64 + PPC | KVM_REG_PPC_BESCR | 64 + PPC | KVM_REG_PPC_TAR | 64 + PPC | KVM_REG_PPC_DPDES | 64 + PPC | KVM_REG_PPC_DAWR | 64 + PPC | KVM_REG_PPC_DAWRX | 64 + PPC | KVM_REG_PPC_CIABR | 64 + PPC | KVM_REG_PPC_IC | 64 + PPC | KVM_REG_PPC_VTB | 64 + PPC | KVM_REG_PPC_CSIGR | 64 + PPC | KVM_REG_PPC_TACR | 64 + PPC | KVM_REG_PPC_TCSCR | 64 + PPC | KVM_REG_PPC_PID | 64 + PPC | KVM_REG_PPC_ACOP | 64 + PPC | KVM_REG_PPC_VRSAVE | 32 + PPC | KVM_REG_PPC_LPCR | 64 + PPC | KVM_REG_PPC_PPR | 64 + PPC | KVM_REG_PPC_ARCH_COMPAT 32 + PPC | KVM_REG_PPC_DABRX | 32 + PPC | KVM_REG_PPC_WORT | 64 + PPC | KVM_REG_PPC_TM_GPR0 | 64 + ... + PPC | KVM_REG_PPC_TM_GPR31 | 64 + PPC | KVM_REG_PPC_TM_VSR0 | 128 + ... + PPC | KVM_REG_PPC_TM_VSR63 | 128 + PPC | KVM_REG_PPC_TM_CR | 64 + PPC | KVM_REG_PPC_TM_LR | 64 + PPC | KVM_REG_PPC_TM_CTR | 64 + PPC | KVM_REG_PPC_TM_FPSCR | 64 + PPC | KVM_REG_PPC_TM_AMR | 64 + PPC | KVM_REG_PPC_TM_PPR | 64 + PPC | KVM_REG_PPC_TM_VRSAVE | 64 + PPC | KVM_REG_PPC_TM_VSCR | 32 + PPC | KVM_REG_PPC_TM_DSCR | 64 + PPC | KVM_REG_PPC_TM_TAR | 64 + +ARM registers are mapped using the lower 32 bits. The upper 16 of that +is the register group type, or coprocessor number: + +ARM core registers have the following id bit patterns: + 0x4020 0000 0010 <index into the kvm_regs struct:16> + +ARM 32-bit CP15 registers have the following id bit patterns: + 0x4020 0000 000F <zero:1> <crn:4> <crm:4> <opc1:4> <opc2:3> + +ARM 64-bit CP15 registers have the following id bit patterns: + 0x4030 0000 000F <zero:1> <zero:4> <crm:4> <opc1:4> <zero:3> + +ARM CCSIDR registers are demultiplexed by CSSELR value: + 0x4020 0000 0011 00 <csselr:8> + +ARM 32-bit VFP control registers have the following id bit patterns: + 0x4020 0000 0012 1 <regno:12> + +ARM 64-bit FP registers have the following id bit patterns: + 0x4030 0000 0012 0 <regno:12> + + +arm64 registers are mapped using the lower 32 bits. The upper 16 of +that is the register group type, or coprocessor number: + +arm64 core/FP-SIMD registers have the following id bit patterns. Note +that the size of the access is variable, as the kvm_regs structure +contains elements ranging from 32 to 128 bits. The index is a 32bit +value in the kvm_regs structure seen as a 32bit array. + 0x60x0 0000 0010 <index into the kvm_regs struct:16> + +arm64 CCSIDR registers are demultiplexed by CSSELR value: + 0x6020 0000 0011 00 <csselr:8> + +arm64 system registers have the following id bit patterns: + 0x6030 0000 0013 <op0:2> <op1:3> <crn:4> <crm:4> <op2:3> 4.69 KVM_GET_ONE_REG @@ -1667,9 +1942,560 @@ kvm_one_reg struct passed in. On success, the register value can be found at the memory location pointed to by "addr". The list of registers accessible using this interface is identical to the -list in 4.64. +list in 4.68. + + +4.70 KVM_KVMCLOCK_CTRL + +Capability: KVM_CAP_KVMCLOCK_CTRL +Architectures: Any that implement pvclocks (currently x86 only) +Type: vcpu ioctl +Parameters: None +Returns: 0 on success, -1 on error + +This signals to the host kernel that the specified guest is being paused by +userspace. The host will set a flag in the pvclock structure that is checked +from the soft lockup watchdog. The flag is part of the pvclock structure that +is shared between guest and host, specifically the second bit of the flags +field of the pvclock_vcpu_time_info structure. It will be set exclusively by +the host and read/cleared exclusively by the guest. The guest operation of +checking and clearing the flag must an atomic operation so +load-link/store-conditional, or equivalent must be used. There are two cases +where the guest will clear the flag: when the soft lockup watchdog timer resets +itself or when a soft lockup is detected. This ioctl can be called any time +after pausing the vcpu, but before it is resumed. + + +4.71 KVM_SIGNAL_MSI + +Capability: KVM_CAP_SIGNAL_MSI +Architectures: x86 +Type: vm ioctl +Parameters: struct kvm_msi (in) +Returns: >0 on delivery, 0 if guest blocked the MSI, and -1 on error + +Directly inject a MSI message. Only valid with in-kernel irqchip that handles +MSI messages. + +struct kvm_msi { + __u32 address_lo; + __u32 address_hi; + __u32 data; + __u32 flags; + __u8 pad[16]; +}; + +No flags are defined so far. The corresponding field must be 0. + + +4.71 KVM_CREATE_PIT2 + +Capability: KVM_CAP_PIT2 +Architectures: x86 +Type: vm ioctl +Parameters: struct kvm_pit_config (in) +Returns: 0 on success, -1 on error + +Creates an in-kernel device model for the i8254 PIT. This call is only valid +after enabling in-kernel irqchip support via KVM_CREATE_IRQCHIP. The following +parameters have to be passed: + +struct kvm_pit_config { + __u32 flags; + __u32 pad[15]; +}; + +Valid flags are: + +#define KVM_PIT_SPEAKER_DUMMY 1 /* emulate speaker port stub */ + +PIT timer interrupts may use a per-VM kernel thread for injection. If it +exists, this thread will have a name of the following pattern: + +kvm-pit/<owner-process-pid> + +When running a guest with elevated priorities, the scheduling parameters of +this thread may have to be adjusted accordingly. + +This IOCTL replaces the obsolete KVM_CREATE_PIT. + + +4.72 KVM_GET_PIT2 + +Capability: KVM_CAP_PIT_STATE2 +Architectures: x86 +Type: vm ioctl +Parameters: struct kvm_pit_state2 (out) +Returns: 0 on success, -1 on error + +Retrieves the state of the in-kernel PIT model. Only valid after +KVM_CREATE_PIT2. The state is returned in the following structure: + +struct kvm_pit_state2 { + struct kvm_pit_channel_state channels[3]; + __u32 flags; + __u32 reserved[9]; +}; + +Valid flags are: + +/* disable PIT in HPET legacy mode */ +#define KVM_PIT_FLAGS_HPET_LEGACY 0x00000001 + +This IOCTL replaces the obsolete KVM_GET_PIT. + + +4.73 KVM_SET_PIT2 + +Capability: KVM_CAP_PIT_STATE2 +Architectures: x86 +Type: vm ioctl +Parameters: struct kvm_pit_state2 (in) +Returns: 0 on success, -1 on error + +Sets the state of the in-kernel PIT model. Only valid after KVM_CREATE_PIT2. +See KVM_GET_PIT2 for details on struct kvm_pit_state2. + +This IOCTL replaces the obsolete KVM_SET_PIT. + + +4.74 KVM_PPC_GET_SMMU_INFO + +Capability: KVM_CAP_PPC_GET_SMMU_INFO +Architectures: powerpc +Type: vm ioctl +Parameters: None +Returns: 0 on success, -1 on error + +This populates and returns a structure describing the features of +the "Server" class MMU emulation supported by KVM. +This can in turn be used by userspace to generate the appropriate +device-tree properties for the guest operating system. + +The structure contains some global information, followed by an +array of supported segment page sizes: + + struct kvm_ppc_smmu_info { + __u64 flags; + __u32 slb_size; + __u32 pad; + struct kvm_ppc_one_seg_page_size sps[KVM_PPC_PAGE_SIZES_MAX_SZ]; + }; + +The supported flags are: + + - KVM_PPC_PAGE_SIZES_REAL: + When that flag is set, guest page sizes must "fit" the backing + store page sizes. When not set, any page size in the list can + be used regardless of how they are backed by userspace. + + - KVM_PPC_1T_SEGMENTS + The emulated MMU supports 1T segments in addition to the + standard 256M ones. + +The "slb_size" field indicates how many SLB entries are supported + +The "sps" array contains 8 entries indicating the supported base +page sizes for a segment in increasing order. Each entry is defined +as follow: + + struct kvm_ppc_one_seg_page_size { + __u32 page_shift; /* Base page shift of segment (or 0) */ + __u32 slb_enc; /* SLB encoding for BookS */ + struct kvm_ppc_one_page_size enc[KVM_PPC_PAGE_SIZES_MAX_SZ]; + }; + +An entry with a "page_shift" of 0 is unused. Because the array is +organized in increasing order, a lookup can stop when encoutering +such an entry. + +The "slb_enc" field provides the encoding to use in the SLB for the +page size. The bits are in positions such as the value can directly +be OR'ed into the "vsid" argument of the slbmte instruction. + +The "enc" array is a list which for each of those segment base page +size provides the list of supported actual page sizes (which can be +only larger or equal to the base page size), along with the +corresponding encoding in the hash PTE. Similarly, the array is +8 entries sorted by increasing sizes and an entry with a "0" shift +is an empty entry and a terminator: + + struct kvm_ppc_one_page_size { + __u32 page_shift; /* Page shift (or 0) */ + __u32 pte_enc; /* Encoding in the HPTE (>>12) */ + }; + +The "pte_enc" field provides a value that can OR'ed into the hash +PTE's RPN field (ie, it needs to be shifted left by 12 to OR it +into the hash PTE second double word). + +4.75 KVM_IRQFD + +Capability: KVM_CAP_IRQFD +Architectures: x86 s390 +Type: vm ioctl +Parameters: struct kvm_irqfd (in) +Returns: 0 on success, -1 on error + +Allows setting an eventfd to directly trigger a guest interrupt. +kvm_irqfd.fd specifies the file descriptor to use as the eventfd and +kvm_irqfd.gsi specifies the irqchip pin toggled by this event. When +an event is triggered on the eventfd, an interrupt is injected into +the guest using the specified gsi pin. The irqfd is removed using +the KVM_IRQFD_FLAG_DEASSIGN flag, specifying both kvm_irqfd.fd +and kvm_irqfd.gsi. + +With KVM_CAP_IRQFD_RESAMPLE, KVM_IRQFD supports a de-assert and notify +mechanism allowing emulation of level-triggered, irqfd-based +interrupts. When KVM_IRQFD_FLAG_RESAMPLE is set the user must pass an +additional eventfd in the kvm_irqfd.resamplefd field. When operating +in resample mode, posting of an interrupt through kvm_irq.fd asserts +the specified gsi in the irqchip. When the irqchip is resampled, such +as from an EOI, the gsi is de-asserted and the user is notified via +kvm_irqfd.resamplefd. It is the user's responsibility to re-queue +the interrupt if the device making use of it still requires service. +Note that closing the resamplefd is not sufficient to disable the +irqfd. The KVM_IRQFD_FLAG_RESAMPLE is only necessary on assignment +and need not be specified with KVM_IRQFD_FLAG_DEASSIGN. + +4.76 KVM_PPC_ALLOCATE_HTAB + +Capability: KVM_CAP_PPC_ALLOC_HTAB +Architectures: powerpc +Type: vm ioctl +Parameters: Pointer to u32 containing hash table order (in/out) +Returns: 0 on success, -1 on error + +This requests the host kernel to allocate an MMU hash table for a +guest using the PAPR paravirtualization interface. This only does +anything if the kernel is configured to use the Book 3S HV style of +virtualization. Otherwise the capability doesn't exist and the ioctl +returns an ENOTTY error. The rest of this description assumes Book 3S +HV. + +There must be no vcpus running when this ioctl is called; if there +are, it will do nothing and return an EBUSY error. + +The parameter is a pointer to a 32-bit unsigned integer variable +containing the order (log base 2) of the desired size of the hash +table, which must be between 18 and 46. On successful return from the +ioctl, it will have been updated with the order of the hash table that +was allocated. + +If no hash table has been allocated when any vcpu is asked to run +(with the KVM_RUN ioctl), the host kernel will allocate a +default-sized hash table (16 MB). + +If this ioctl is called when a hash table has already been allocated, +the kernel will clear out the existing hash table (zero all HPTEs) and +return the hash table order in the parameter. (If the guest is using +the virtualized real-mode area (VRMA) facility, the kernel will +re-create the VMRA HPTEs on the next KVM_RUN of any vcpu.) + +4.77 KVM_S390_INTERRUPT + +Capability: basic +Architectures: s390 +Type: vm ioctl, vcpu ioctl +Parameters: struct kvm_s390_interrupt (in) +Returns: 0 on success, -1 on error + +Allows to inject an interrupt to the guest. Interrupts can be floating +(vm ioctl) or per cpu (vcpu ioctl), depending on the interrupt type. + +Interrupt parameters are passed via kvm_s390_interrupt: + +struct kvm_s390_interrupt { + __u32 type; + __u32 parm; + __u64 parm64; +}; + +type can be one of the following: + +KVM_S390_SIGP_STOP (vcpu) - sigp restart +KVM_S390_PROGRAM_INT (vcpu) - program check; code in parm +KVM_S390_SIGP_SET_PREFIX (vcpu) - sigp set prefix; prefix address in parm +KVM_S390_RESTART (vcpu) - restart +KVM_S390_INT_CLOCK_COMP (vcpu) - clock comparator interrupt +KVM_S390_INT_CPU_TIMER (vcpu) - CPU timer interrupt +KVM_S390_INT_VIRTIO (vm) - virtio external interrupt; external interrupt + parameters in parm and parm64 +KVM_S390_INT_SERVICE (vm) - sclp external interrupt; sclp parameter in parm +KVM_S390_INT_EMERGENCY (vcpu) - sigp emergency; source cpu in parm +KVM_S390_INT_EXTERNAL_CALL (vcpu) - sigp external call; source cpu in parm +KVM_S390_INT_IO(ai,cssid,ssid,schid) (vm) - compound value to indicate an + I/O interrupt (ai - adapter interrupt; cssid,ssid,schid - subchannel); + I/O interruption parameters in parm (subchannel) and parm64 (intparm, + interruption subclass) +KVM_S390_MCHK (vm, vcpu) - machine check interrupt; cr 14 bits in parm, + machine check interrupt code in parm64 (note that + machine checks needing further payload are not + supported by this ioctl) + +Note that the vcpu ioctl is asynchronous to vcpu execution. + +4.78 KVM_PPC_GET_HTAB_FD + +Capability: KVM_CAP_PPC_HTAB_FD +Architectures: powerpc +Type: vm ioctl +Parameters: Pointer to struct kvm_get_htab_fd (in) +Returns: file descriptor number (>= 0) on success, -1 on error + +This returns a file descriptor that can be used either to read out the +entries in the guest's hashed page table (HPT), or to write entries to +initialize the HPT. The returned fd can only be written to if the +KVM_GET_HTAB_WRITE bit is set in the flags field of the argument, and +can only be read if that bit is clear. The argument struct looks like +this: + +/* For KVM_PPC_GET_HTAB_FD */ +struct kvm_get_htab_fd { + __u64 flags; + __u64 start_index; + __u64 reserved[2]; +}; + +/* Values for kvm_get_htab_fd.flags */ +#define KVM_GET_HTAB_BOLTED_ONLY ((__u64)0x1) +#define KVM_GET_HTAB_WRITE ((__u64)0x2) + +The `start_index' field gives the index in the HPT of the entry at +which to start reading. It is ignored when writing. + +Reads on the fd will initially supply information about all +"interesting" HPT entries. Interesting entries are those with the +bolted bit set, if the KVM_GET_HTAB_BOLTED_ONLY bit is set, otherwise +all entries. When the end of the HPT is reached, the read() will +return. If read() is called again on the fd, it will start again from +the beginning of the HPT, but will only return HPT entries that have +changed since they were last read. + +Data read or written is structured as a header (8 bytes) followed by a +series of valid HPT entries (16 bytes) each. The header indicates how +many valid HPT entries there are and how many invalid entries follow +the valid entries. The invalid entries are not represented explicitly +in the stream. The header format is: + +struct kvm_get_htab_header { + __u32 index; + __u16 n_valid; + __u16 n_invalid; +}; + +Writes to the fd create HPT entries starting at the index given in the +header; first `n_valid' valid entries with contents from the data +written, then `n_invalid' invalid entries, invalidating any previously +valid entries found. + +4.79 KVM_CREATE_DEVICE + +Capability: KVM_CAP_DEVICE_CTRL +Type: vm ioctl +Parameters: struct kvm_create_device (in/out) +Returns: 0 on success, -1 on error +Errors: + ENODEV: The device type is unknown or unsupported + EEXIST: Device already created, and this type of device may not + be instantiated multiple times + + Other error conditions may be defined by individual device types or + have their standard meanings. + +Creates an emulated device in the kernel. The file descriptor returned +in fd can be used with KVM_SET/GET/HAS_DEVICE_ATTR. + +If the KVM_CREATE_DEVICE_TEST flag is set, only test whether the +device type is supported (not necessarily whether it can be created +in the current vm). + +Individual devices should not define flags. Attributes should be used +for specifying any behavior that is not implied by the device type +number. + +struct kvm_create_device { + __u32 type; /* in: KVM_DEV_TYPE_xxx */ + __u32 fd; /* out: device handle */ + __u32 flags; /* in: KVM_CREATE_DEVICE_xxx */ +}; + +4.80 KVM_SET_DEVICE_ATTR/KVM_GET_DEVICE_ATTR + +Capability: KVM_CAP_DEVICE_CTRL, KVM_CAP_VM_ATTRIBUTES for vm device +Type: device ioctl, vm ioctl +Parameters: struct kvm_device_attr +Returns: 0 on success, -1 on error +Errors: + ENXIO: The group or attribute is unknown/unsupported for this device + EPERM: The attribute cannot (currently) be accessed this way + (e.g. read-only attribute, or attribute that only makes + sense when the device is in a different state) + + Other error conditions may be defined by individual device types. + +Gets/sets a specified piece of device configuration and/or state. The +semantics are device-specific. See individual device documentation in +the "devices" directory. As with ONE_REG, the size of the data +transferred is defined by the particular attribute. + +struct kvm_device_attr { + __u32 flags; /* no flags currently defined */ + __u32 group; /* device-defined */ + __u64 attr; /* group-defined */ + __u64 addr; /* userspace address of attr data */ +}; + +4.81 KVM_HAS_DEVICE_ATTR + +Capability: KVM_CAP_DEVICE_CTRL, KVM_CAP_VM_ATTRIBUTES for vm device +Type: device ioctl, vm ioctl +Parameters: struct kvm_device_attr +Returns: 0 on success, -1 on error +Errors: + ENXIO: The group or attribute is unknown/unsupported for this device + +Tests whether a device supports a particular attribute. A successful +return indicates the attribute is implemented. It does not necessarily +indicate that the attribute can be read or written in the device's +current state. "addr" is ignored. + +4.82 KVM_ARM_VCPU_INIT + +Capability: basic +Architectures: arm, arm64 +Type: vcpu ioctl +Parameters: struct kvm_vcpu_init (in) +Returns: 0 on success; -1 on error +Errors: + EINVAL: the target is unknown, or the combination of features is invalid. + ENOENT: a features bit specified is unknown. + +This tells KVM what type of CPU to present to the guest, and what +optional features it should have. This will cause a reset of the cpu +registers to their initial values. If this is not called, KVM_RUN will +return ENOEXEC for that vcpu. + +Note that because some registers reflect machine topology, all vcpus +should be created before this ioctl is invoked. + +Possible features: + - KVM_ARM_VCPU_POWER_OFF: Starts the CPU in a power-off state. + Depends on KVM_CAP_ARM_PSCI. + - KVM_ARM_VCPU_EL1_32BIT: Starts the CPU in a 32bit mode. + Depends on KVM_CAP_ARM_EL1_32BIT (arm64 only). + - KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI v0.2 for the CPU. + Depends on KVM_CAP_ARM_PSCI_0_2. + + +4.83 KVM_ARM_PREFERRED_TARGET + +Capability: basic +Architectures: arm, arm64 +Type: vm ioctl +Parameters: struct struct kvm_vcpu_init (out) +Returns: 0 on success; -1 on error +Errors: + ENODEV: no preferred target available for the host + +This queries KVM for preferred CPU target type which can be emulated +by KVM on underlying host. + +The ioctl returns struct kvm_vcpu_init instance containing information +about preferred CPU target type and recommended features for it. The +kvm_vcpu_init->features bitmap returned will have feature bits set if +the preferred target recommends setting these features, but this is +not mandatory. + +The information returned by this ioctl can be used to prepare an instance +of struct kvm_vcpu_init for KVM_ARM_VCPU_INIT ioctl which will result in +in VCPU matching underlying host. + + +4.84 KVM_GET_REG_LIST + +Capability: basic +Architectures: arm, arm64 +Type: vcpu ioctl +Parameters: struct kvm_reg_list (in/out) +Returns: 0 on success; -1 on error +Errors: + E2BIG: the reg index list is too big to fit in the array specified by + the user (the number required will be written into n). + +struct kvm_reg_list { + __u64 n; /* number of registers in reg[] */ + __u64 reg[0]; +}; + +This ioctl returns the guest registers that are supported for the +KVM_GET_ONE_REG/KVM_SET_ONE_REG calls. + + +4.85 KVM_ARM_SET_DEVICE_ADDR (deprecated) + +Capability: KVM_CAP_ARM_SET_DEVICE_ADDR +Architectures: arm, arm64 +Type: vm ioctl +Parameters: struct kvm_arm_device_address (in) +Returns: 0 on success, -1 on error +Errors: + ENODEV: The device id is unknown + ENXIO: Device not supported on current system + EEXIST: Address already set + E2BIG: Address outside guest physical address space + EBUSY: Address overlaps with other device range + +struct kvm_arm_device_addr { + __u64 id; + __u64 addr; +}; + +Specify a device address in the guest's physical address space where guests +can access emulated or directly exposed devices, which the host kernel needs +to know about. The id field is an architecture specific identifier for a +specific device. + +ARM/arm64 divides the id field into two parts, a device id and an +address type id specific to the individual device. + + bits: | 63 ... 32 | 31 ... 16 | 15 ... 0 | + field: | 0x00000000 | device id | addr type id | + +ARM/arm64 currently only require this when using the in-kernel GIC +support for the hardware VGIC features, using KVM_ARM_DEVICE_VGIC_V2 +as the device id. When setting the base address for the guest's +mapping of the VGIC virtual CPU and distributor interface, the ioctl +must be called after calling KVM_CREATE_IRQCHIP, but before calling +KVM_RUN on any of the VCPUs. Calling this ioctl twice for any of the +base addresses will return -EEXIST. + +Note, this IOCTL is deprecated and the more flexible SET/GET_DEVICE_ATTR API +should be used instead. + + +4.86 KVM_PPC_RTAS_DEFINE_TOKEN + +Capability: KVM_CAP_PPC_RTAS +Architectures: ppc +Type: vm ioctl +Parameters: struct kvm_rtas_token_args +Returns: 0 on success, -1 on error + +Defines a token value for a RTAS (Run Time Abstraction Services) +service in order to allow it to be handled in the kernel. The +argument struct gives the name of the service, which must be the name +of a service that has a kernel-side implementation. If the token +value is non-zero, it will be associated with that service, and +subsequent RTAS calls by the guest specifying that token will be +handled by the kernel. If the token value is 0, then any token +associated with the service will be forgotten, and subsequent RTAS +calls by the guest for that service will be passed to userspace to be +handled. + 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 @@ -1779,7 +2605,12 @@ 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. -NOTE: For KVM_EXIT_IO, KVM_EXIT_MMIO and KVM_EXIT_OSI, the corresponding +The 'data' member contains, in its first 'len' bytes, the value as it would +appear if the VCPU performed a load or store of the appropriate width directly +to the byte array. + +NOTE: For KVM_EXIT_IO, KVM_EXIT_MMIO, KVM_EXIT_OSI, KVM_EXIT_DCR, + KVM_EXIT_PAPR and KVM_EXIT_EPR the corresponding operations are complete (and guest state is consistent) only after userspace has re-entered the kernel with KVM_RUN. The kernel side will first finish incomplete operations and then check for pending signals. Userspace @@ -1882,6 +2713,56 @@ The possible hypercalls are defined in the Power Architecture Platform Requirements (PAPR) document available from www.power.org (free developer registration required to access it). + /* KVM_EXIT_S390_TSCH */ + struct { + __u16 subchannel_id; + __u16 subchannel_nr; + __u32 io_int_parm; + __u32 io_int_word; + __u32 ipb; + __u8 dequeued; + } s390_tsch; + +s390 specific. This exit occurs when KVM_CAP_S390_CSS_SUPPORT has been enabled +and TEST SUBCHANNEL was intercepted. If dequeued is set, a pending I/O +interrupt for the target subchannel has been dequeued and subchannel_id, +subchannel_nr, io_int_parm and io_int_word contain the parameters for that +interrupt. ipb is needed for instruction parameter decoding. + + /* KVM_EXIT_EPR */ + struct { + __u32 epr; + } epr; + +On FSL BookE PowerPC chips, the interrupt controller has a fast patch +interrupt acknowledge path to the core. When the core successfully +delivers an interrupt, it automatically populates the EPR register with +the interrupt vector number and acknowledges the interrupt inside +the interrupt controller. + +In case the interrupt controller lives in user space, we need to do +the interrupt acknowledge cycle through it to fetch the next to be +delivered interrupt vector using this exit. + +It gets triggered whenever both KVM_CAP_PPC_EPR are enabled and an +external interrupt has just been delivered into the guest. User space +should put the acknowledged interrupt vector into the 'epr' field. + + /* KVM_EXIT_SYSTEM_EVENT */ + struct { +#define KVM_SYSTEM_EVENT_SHUTDOWN 1 +#define KVM_SYSTEM_EVENT_RESET 2 + __u32 type; + __u64 flags; + } system_event; + +If exit_reason is KVM_EXIT_SYSTEM_EVENT then the vcpu has triggered +a system-level event using some architecture specific mechanism (hypercall +or some special instruction). In case of ARM/ARM64, this is triggered using +HVC instruction based PSCI call from the vcpu. The 'type' field describes +the system-level event type. The 'flags' field describes architecture +specific flags for the system-level event. + /* Fix the size of the union. */ char padding[256]; }; @@ -1910,7 +2791,80 @@ and usually define the validity of a groups of registers. (e.g. one bit }; + +4.81 KVM_GET_EMULATED_CPUID + +Capability: KVM_CAP_EXT_EMUL_CPUID +Architectures: x86 +Type: system ioctl +Parameters: struct kvm_cpuid2 (in/out) +Returns: 0 on success, -1 on error + +struct kvm_cpuid2 { + __u32 nent; + __u32 flags; + struct kvm_cpuid_entry2 entries[0]; +}; + +The member 'flags' is used for passing flags from userspace. + +#define KVM_CPUID_FLAG_SIGNIFCANT_INDEX BIT(0) +#define KVM_CPUID_FLAG_STATEFUL_FUNC BIT(1) +#define KVM_CPUID_FLAG_STATE_READ_NEXT BIT(2) + +struct kvm_cpuid_entry2 { + __u32 function; + __u32 index; + __u32 flags; + __u32 eax; + __u32 ebx; + __u32 ecx; + __u32 edx; + __u32 padding[3]; +}; + +This ioctl returns x86 cpuid features which are emulated by +kvm.Userspace can use the information returned by this ioctl to query +which features are emulated by kvm instead of being present natively. + +Userspace invokes KVM_GET_EMULATED_CPUID by passing a kvm_cpuid2 +structure with the 'nent' field indicating the number of entries in +the variable-size array 'entries'. If the number of entries is too low +to describe the cpu capabilities, an error (E2BIG) is returned. If the +number is too high, the 'nent' field is adjusted and an error (ENOMEM) +is returned. If the number is just right, the 'nent' field is adjusted +to the number of valid entries in the 'entries' array, which is then +filled. + +The entries returned are the set CPUID bits of the respective features +which kvm emulates, as returned by the CPUID instruction, with unknown +or unsupported feature bits cleared. + +Features like x2apic, for example, may not be present in the host cpu +but are exposed by kvm in KVM_GET_SUPPORTED_CPUID because they can be +emulated efficiently and thus not included here. + +The fields in each entry are defined as follows: + + function: the eax value used to obtain the entry + index: the ecx value used to obtain the entry (for entries that are + affected by ecx) + flags: an OR of zero or more of the following: + KVM_CPUID_FLAG_SIGNIFCANT_INDEX: + if the index field is valid + KVM_CPUID_FLAG_STATEFUL_FUNC: + if cpuid for this function returns different values for successive + invocations; there will be several entries with the same function, + all with this flag set + KVM_CPUID_FLAG_STATE_READ_NEXT: + for KVM_CPUID_FLAG_STATEFUL_FUNC entries, set if this entry is + the first entry to be read by a cpu + eax, ebx, ecx, edx: the values returned by the cpuid instruction for + this function/index combination + + 6. Capabilities that can be enabled +----------------------------------- There are certain capabilities that change the behavior of the virtual CPU when enabled. To enable them, please see section 4.37. Below you can find a list of @@ -1926,6 +2880,7 @@ The following information is provided along with the description: Returns: the return value. General error numbers (EBADF, ENOMEM, EINVAL) are not detailed, but errors with specific meanings are. + 6.1 KVM_CAP_PPC_OSI Architectures: ppc @@ -1939,6 +2894,7 @@ between the guest and the host. When this capability is enabled, KVM_EXIT_OSI can occur. + 6.2 KVM_CAP_PPC_PAPR Architectures: ppc @@ -1957,6 +2913,7 @@ HTAB invisible to the guest. When this capability is enabled, KVM_EXIT_PAPR_HCALL can occur. + 6.3 KVM_CAP_SW_TLB Architectures: ppc @@ -1998,3 +2955,50 @@ For mmu types KVM_MMU_FSL_BOOKE_NOHV and KVM_MMU_FSL_BOOKE_HV: where "num_sets" is the tlb_sizes[] value divided by the tlb_ways[] value. - The tsize field of mas1 shall be set to 4K on TLB0, even though the hardware ignores this value for TLB0. + +6.4 KVM_CAP_S390_CSS_SUPPORT + +Architectures: s390 +Parameters: none +Returns: 0 on success; -1 on error + +This capability enables support for handling of channel I/O instructions. + +TEST PENDING INTERRUPTION and the interrupt portion of TEST SUBCHANNEL are +handled in-kernel, while the other I/O instructions are passed to userspace. + +When this capability is enabled, KVM_EXIT_S390_TSCH will occur on TEST +SUBCHANNEL intercepts. + +6.5 KVM_CAP_PPC_EPR + +Architectures: ppc +Parameters: args[0] defines whether the proxy facility is active +Returns: 0 on success; -1 on error + +This capability enables or disables the delivery of interrupts through the +external proxy facility. + +When enabled (args[0] != 0), every time the guest gets an external interrupt +delivered, it automatically exits into user space with a KVM_EXIT_EPR exit +to receive the topmost interrupt vector. + +When disabled (args[0] == 0), behavior is as if this facility is unsupported. + +When this capability is enabled, KVM_EXIT_EPR can occur. + +6.6 KVM_CAP_IRQ_MPIC + +Architectures: ppc +Parameters: args[0] is the MPIC device fd + args[1] is the MPIC CPU number for this vcpu + +This capability connects the vcpu to an in-kernel MPIC device. + +6.7 KVM_CAP_IRQ_XICS + +Architectures: ppc +Parameters: args[0] is the XICS device fd + args[1] is the XICS CPU number (server ID) for this vcpu + +This capability connects the vcpu to an in-kernel XICS device. |