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-rw-r--r--Documentation/virtual/kvm/00-INDEX24
-rw-r--r--Documentation/virtual/kvm/api.txt152
-rw-r--r--Documentation/virtual/kvm/cpuid.txt7
-rw-r--r--Documentation/virtual/kvm/devices/vfio.txt22
-rw-r--r--Documentation/virtual/kvm/locking.txt19
5 files changed, 215 insertions, 9 deletions
diff --git a/Documentation/virtual/kvm/00-INDEX b/Documentation/virtual/kvm/00-INDEX
new file mode 100644
index 00000000000..641ec922017
--- /dev/null
+++ b/Documentation/virtual/kvm/00-INDEX
@@ -0,0 +1,24 @@
+00-INDEX
+ - this file.
+api.txt
+ - KVM userspace API.
+cpuid.txt
+ - KVM-specific cpuid leaves (x86).
+devices/
+ - KVM_CAP_DEVICE_CTRL userspace API.
+hypercalls.txt
+ - KVM hypercalls.
+locking.txt
+ - notes on KVM locks.
+mmu.txt
+ - the x86 kvm shadow mmu.
+msr.txt
+ - KVM-specific MSRs (x86).
+nested-vmx.txt
+ - notes on nested virtualization for Intel x86 processors.
+ppc-pv.txt
+ - the paravirtualization interface on PowerPC.
+review-checklist.txt
+ - review checklist for KVM patches.
+timekeeping.txt
+ - timekeeping virtualization for x86-based architectures.
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 858aecf21db..a30035dd4c2 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -1122,9 +1122,9 @@ 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;
@@ -1810,6 +1810,50 @@ registers, find a list below:
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_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:
@@ -2304,7 +2348,31 @@ Possible features:
Depends on KVM_CAP_ARM_EL1_32BIT (arm64 only).
-4.83 KVM_GET_REG_LIST
+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
@@ -2323,8 +2391,7 @@ struct kvm_reg_list {
This ioctl returns the guest registers that are supported for the
KVM_GET_ONE_REG/KVM_SET_ONE_REG calls.
-
-4.84 KVM_ARM_SET_DEVICE_ADDR
+4.85 KVM_ARM_SET_DEVICE_ADDR
Capability: KVM_CAP_ARM_SET_DEVICE_ADDR
Architectures: arm, arm64
@@ -2362,7 +2429,7 @@ 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.
-4.85 KVM_PPC_RTAS_DEFINE_TOKEN
+4.86 KVM_PPC_RTAS_DEFINE_TOKEN
Capability: KVM_CAP_PPC_RTAS
Architectures: ppc
@@ -2661,6 +2728,77 @@ 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
-----------------------------------
diff --git a/Documentation/virtual/kvm/cpuid.txt b/Documentation/virtual/kvm/cpuid.txt
index 22ff659bc0f..3c65feb8301 100644
--- a/Documentation/virtual/kvm/cpuid.txt
+++ b/Documentation/virtual/kvm/cpuid.txt
@@ -43,6 +43,13 @@ KVM_FEATURE_CLOCKSOURCE2 || 3 || kvmclock available at msrs
KVM_FEATURE_ASYNC_PF || 4 || async pf can be enabled by
|| || writing to msr 0x4b564d02
------------------------------------------------------------------------------
+KVM_FEATURE_STEAL_TIME || 5 || steal time can be enabled by
+ || || writing to msr 0x4b564d03.
+------------------------------------------------------------------------------
+KVM_FEATURE_PV_EOI || 6 || paravirtualized end of interrupt
+ || || handler can be enabled by writing
+ || || to msr 0x4b564d04.
+------------------------------------------------------------------------------
KVM_FEATURE_PV_UNHALT || 7 || guest checks this feature bit
|| || before enabling paravirtualized
|| || spinlock support.
diff --git a/Documentation/virtual/kvm/devices/vfio.txt b/Documentation/virtual/kvm/devices/vfio.txt
new file mode 100644
index 00000000000..ef51740c67c
--- /dev/null
+++ b/Documentation/virtual/kvm/devices/vfio.txt
@@ -0,0 +1,22 @@
+VFIO virtual device
+===================
+
+Device types supported:
+ KVM_DEV_TYPE_VFIO
+
+Only one VFIO instance may be created per VM. The created device
+tracks VFIO groups in use by the VM and features of those groups
+important to the correctness and acceleration of the VM. As groups
+are enabled and disabled for use by the VM, KVM should be updated
+about their presence. When registered with KVM, a reference to the
+VFIO-group is held by KVM.
+
+Groups:
+ KVM_DEV_VFIO_GROUP
+
+KVM_DEV_VFIO_GROUP attributes:
+ KVM_DEV_VFIO_GROUP_ADD: Add a VFIO group to VFIO-KVM device tracking
+ KVM_DEV_VFIO_GROUP_DEL: Remove a VFIO group from VFIO-KVM device tracking
+
+For each, kvm_device_attr.addr points to an int32_t file descriptor
+for the VFIO group.
diff --git a/Documentation/virtual/kvm/locking.txt b/Documentation/virtual/kvm/locking.txt
index 41b7ac9884b..f8869410d40 100644
--- a/Documentation/virtual/kvm/locking.txt
+++ b/Documentation/virtual/kvm/locking.txt
@@ -132,10 +132,14 @@ See the comments in spte_has_volatile_bits() and mmu_spte_update().
------------
Name: kvm_lock
-Type: raw_spinlock
+Type: spinlock_t
Arch: any
Protects: - vm_list
- - hardware virtualization enable/disable
+
+Name: kvm_count_lock
+Type: raw_spinlock_t
+Arch: any
+Protects: - hardware virtualization enable/disable
Comment: 'raw' because hardware enabling/disabling must be atomic /wrt
migration.
@@ -151,3 +155,14 @@ Type: spinlock_t
Arch: any
Protects: -shadow page/shadow tlb entry
Comment: it is a spinlock since it is used in mmu notifier.
+
+Name: kvm->srcu
+Type: srcu lock
+Arch: any
+Protects: - kvm->memslots
+ - kvm->buses
+Comment: The srcu read lock must be held while accessing memslots (e.g.
+ when using gfn_to_* functions) and while accessing in-kernel
+ MMIO/PIO address->device structure mapping (kvm->buses).
+ The srcu index can be stored in kvm_vcpu->srcu_idx per vcpu
+ if it is needed by multiple functions.