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authorAlex Bennée <alex.bennee@linaro.org>2014-09-09 20:27:19 +0400
committerPaolo Bonzini <pbonzini@redhat.com>2014-09-10 13:34:39 +0400
commit209cf19fcd927e6db9f2ef38e3ca6afdcc0d4d5a (patch)
tree397489460e9dc22be8b6a0721c5e91afa29f9f3b /Documentation/virtual/kvm
parent4bd9d3441edadff4c8df9de4b5d5386c36667ca6 (diff)
downloadlinux-209cf19fcd927e6db9f2ef38e3ca6afdcc0d4d5a.tar.xz
KVM: fix api documentation of KVM_GET_EMULATED_CPUID
It looks like when this was initially merged it got accidentally included in the following section. I've just moved it back in the correct section and re-numbered it as other ioctls have been added since. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'Documentation/virtual/kvm')
-rw-r--r--Documentation/virtual/kvm/api.txt140
1 files changed, 70 insertions, 70 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 539c010eade0..f7735c72c128 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -2610,6 +2610,76 @@ When debug events exit the main run loop with the reason
KVM_EXIT_DEBUG with the kvm_debug_exit_arch part of the kvm_run
structure containing architecture specific debug information.
+4.88 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
+
5. The kvm_run structure
------------------------
@@ -2912,76 +2982,6 @@ values in kvm_run even if the corresponding bit in kvm_dirty_regs is not set.
};
-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 on vCPUs
--------------------------------------------