KVM: document KVM_REINJECT_CONTROL ioctl

The rest of functionality is identical to KVM_CREATE_SPAPR_TCE.

4.98 KVM_REINJECT_CONTROL

Capability: KVM_CAP_REINJECT_CONTROL

Architectures: x86

Type: vm ioctl

Parameters: struct kvm_reinject_control (in)

Returns: 0 on success,

         -EFAULT if struct kvm_reinject_control cannot be read,

         -ENXIO if KVM_CREATE_PIT or KVM_CREATE_PIT2 didn't succeed earlier.

i8254 (PIT) has two modes, reinject and !reinject.  The default is reinject,

where KVM queues elapsed i8254 ticks and monitors completion of interrupt from

vector(s) that i8254 injects.  Reinject mode dequeues a tick and injects its

interrupt whenever there isn't a pending interrupt from i8254.

!reinject mode injects an interrupt as soon as a tick arrives.

struct kvm_reinject_control {

	__u8 pit_reinject;

	__u8 reserved[31];

};

pit_reinject = 0 (!reinject mode) is recommended, unless running an old

operating system that uses the PIT for timing (e.g. Linux 2.4.x).

5. The kvm_run structure

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