From 8f2abe6a1e525e878bdf58f68ccd146d543fde84 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Tue, 25 Mar 2008 18:47:23 +0100 Subject: KVM: s390: sie intercept handling This path introduces handling of sie intercepts in three flavors: Intercepts are either handled completely in-kernel by kvm_handle_sie_intercept(), or passed to userspace with corresponding data in struct kvm_run in case kvm_handle_sie_intercept() returns -ENOTSUPP. In case of partial execution in kernel with the need of userspace support, kvm_handle_sie_intercept() may choose to set up struct kvm_run and return -EREMOTE. The trivial intercept reasons are handled in this patch: handle_noop() just does nothing for intercepts that don't require our support at all handle_stop() is called when a cpu enters stopped state, and it drops out to userland after updating our vcpu state handle_validity() faults in the cpu lowcore if needed, or passes the request to userland Acked-by: Martin Schwidefsky Signed-off-by: Christian Borntraeger Signed-off-by: Carsten Otte Signed-off-by: Avi Kivity --- arch/s390/kvm/intercept.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 80 insertions(+) create mode 100644 arch/s390/kvm/intercept.c (limited to 'arch/s390/kvm/intercept.c') diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c new file mode 100644 index 000000000000..e757230b982c --- /dev/null +++ b/arch/s390/kvm/intercept.c @@ -0,0 +1,80 @@ +/* + * intercept.c - in-kernel handling for sie intercepts + * + * Copyright IBM Corp. 2008 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License (version 2 only) + * as published by the Free Software Foundation. + * + * Author(s): Carsten Otte + * Christian Borntraeger + */ + +#include +#include +#include + +#include + +#include "kvm-s390.h" + +static int handle_noop(struct kvm_vcpu *vcpu) +{ + switch (vcpu->arch.sie_block->icptcode) { + case 0x10: + vcpu->stat.exit_external_request++; + break; + case 0x14: + vcpu->stat.exit_external_interrupt++; + break; + default: + break; /* nothing */ + } + return 0; +} + +static int handle_stop(struct kvm_vcpu *vcpu) +{ + vcpu->stat.exit_stop_request++; + VCPU_EVENT(vcpu, 3, "%s", "cpu stopped"); + atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags); + return -ENOTSUPP; +} + +static int handle_validity(struct kvm_vcpu *vcpu) +{ + int viwhy = vcpu->arch.sie_block->ipb >> 16; + vcpu->stat.exit_validity++; + if (viwhy == 0x37) { + fault_in_pages_writeable((char __user *) + vcpu->kvm->arch.guest_origin + + vcpu->arch.sie_block->prefix, + PAGE_SIZE); + return 0; + } + VCPU_EVENT(vcpu, 2, "unhandled validity intercept code %d", + viwhy); + return -ENOTSUPP; +} + +static const intercept_handler_t intercept_funcs[0x48 >> 2] = { + [0x00 >> 2] = handle_noop, + [0x10 >> 2] = handle_noop, + [0x14 >> 2] = handle_noop, + [0x20 >> 2] = handle_validity, + [0x28 >> 2] = handle_stop, +}; + +int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu) +{ + intercept_handler_t func; + u8 code = vcpu->arch.sie_block->icptcode; + + if (code & 3 || code > 0x48) + return -ENOTSUPP; + func = intercept_funcs[code >> 2]; + if (func) + return func(vcpu); + return -ENOTSUPP; +} -- cgit v1.2.3