From 25ed16759660cdfccd4a3cb7d30cce8a797b542a Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 12 May 2015 09:49:14 +0200 Subject: [PATCH] KVM: s390: factor out and fix setting of guest TOD clock Let's move that whole logic into one function. We now always use unsigned values when calculating the epoch (to avoid over/underflow defined). Also, we always have to get all VCPUs out of SIE before doing the update to avoid running differing VCPUs with different TODs. Acked-by: Christian Borntraeger Signed-off-by: David Hildenbrand Signed-off-by: Christian Borntraeger --- arch/s390/kvm/kvm-s390.c | 28 +++++++++++++++++----------- arch/s390/kvm/kvm-s390.h | 1 + arch/s390/kvm/priv.c | 15 +++------------ 3 files changed, 21 insertions(+), 23 deletions(-) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index a0907795f31d..87bd602f326c 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -521,22 +521,12 @@ static int kvm_s390_set_tod_high(struct kvm *kvm, struct kvm_device_attr *attr) static int kvm_s390_set_tod_low(struct kvm *kvm, struct kvm_device_attr *attr) { - struct kvm_vcpu *cur_vcpu; - unsigned int vcpu_idx; u64 gtod; if (copy_from_user(>od, (void __user *)attr->addr, sizeof(gtod))) return -EFAULT; - mutex_lock(&kvm->lock); - preempt_disable(); - kvm->arch.epoch = gtod - get_tod_clock(); - kvm_s390_vcpu_block_all(kvm); - kvm_for_each_vcpu(vcpu_idx, cur_vcpu, kvm) - cur_vcpu->arch.sie_block->epoch = kvm->arch.epoch; - kvm_s390_vcpu_unblock_all(kvm); - preempt_enable(); - mutex_unlock(&kvm->lock); + kvm_s390_set_tod_clock(kvm, gtod); VM_EVENT(kvm, 3, "SET: TOD base: 0x%llx\n", gtod); return 0; } @@ -1906,6 +1896,22 @@ static int kvm_s390_handle_requests(struct kvm_vcpu *vcpu) return 0; } +void kvm_s390_set_tod_clock(struct kvm *kvm, u64 tod) +{ + struct kvm_vcpu *vcpu; + int i; + + mutex_lock(&kvm->lock); + preempt_disable(); + kvm->arch.epoch = tod - get_tod_clock(); + kvm_s390_vcpu_block_all(kvm); + kvm_for_each_vcpu(i, vcpu, kvm) + vcpu->arch.sie_block->epoch = kvm->arch.epoch; + kvm_s390_vcpu_unblock_all(kvm); + preempt_enable(); + mutex_unlock(&kvm->lock); +} + /** * kvm_arch_fault_in_page - fault-in guest page if necessary * @vcpu: The corresponding virtual cpu diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h index 3a368d2a6114..cc15ea3a150e 100644 --- a/arch/s390/kvm/kvm-s390.h +++ b/arch/s390/kvm/kvm-s390.h @@ -231,6 +231,7 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu); int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu); /* implemented in kvm-s390.c */ +void kvm_s390_set_tod_clock(struct kvm *kvm, u64 tod); long kvm_arch_fault_in_page(struct kvm_vcpu *vcpu, gpa_t gpa, int writable); int kvm_s390_store_status_unloaded(struct kvm_vcpu *vcpu, unsigned long addr); int kvm_s390_store_adtl_status_unloaded(struct kvm_vcpu *vcpu, diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c index b253de5b8945..77191b85ea7a 100644 --- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -33,11 +33,9 @@ /* Handle SCK (SET CLOCK) interception */ static int handle_set_clock(struct kvm_vcpu *vcpu) { - struct kvm_vcpu *cpup; - s64 val; - int i, rc; + int rc; ar_t ar; - u64 op2; + u64 op2, val; if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE) return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP); @@ -50,14 +48,7 @@ static int handle_set_clock(struct kvm_vcpu *vcpu) return kvm_s390_inject_prog_cond(vcpu, rc); VCPU_EVENT(vcpu, 3, "SCK: setting guest TOD to 0x%llx", val); - - mutex_lock(&vcpu->kvm->lock); - preempt_disable(); - val = (val - get_tod_clock()) & ~0x3fUL; - kvm_for_each_vcpu(i, cpup, vcpu->kvm) - cpup->arch.sie_block->epoch = val; - preempt_enable(); - mutex_unlock(&vcpu->kvm->lock); + kvm_s390_set_tod_clock(vcpu->kvm, val); kvm_s390_set_psw_cc(vcpu, 0); return 0; -- GitLab