KVM: remove kvm_guest_enter/exit wrappers

[cascardo/linux.git] / arch / s390 / kvm / kvm-s390.c

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 45a8316..d42428c 100644 (file)
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -99,6 +99,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
        { "instruction_stfl", VCPU_STAT(instruction_stfl) },
        { "instruction_tprot", VCPU_STAT(instruction_tprot) },
        { "instruction_sthyi", VCPU_STAT(instruction_sthyi) },
+       { "instruction_sie", VCPU_STAT(instruction_sie) },
        { "instruction_sigp_sense", VCPU_STAT(instruction_sigp_sense) },
        { "instruction_sigp_sense_running", VCPU_STAT(instruction_sigp_sense_running) },
        { "instruction_sigp_external_call", VCPU_STAT(instruction_sigp_external_call) },
@@ -124,6 +125,11 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
        { NULL }
 };
 
+/* allow nested virtualization in KVM (if enabled by user space) */
+static int nested;
+module_param(nested, int, S_IRUGO);
+MODULE_PARM_DESC(nested, "Nested virtualization support");
+
 /* upper facilities limit for kvm */
 unsigned long kvm_s390_fac_list_mask[16] = {
        0xffe6000000000000UL,
@@ -142,6 +148,7 @@ static DECLARE_BITMAP(kvm_s390_available_cpu_feat, KVM_S390_VM_CPU_FEAT_NR_BITS)
 static struct kvm_s390_vm_cpu_subfunc kvm_s390_available_subfunc;
 
 static struct gmap_notifier gmap_notifier;
+static struct gmap_notifier vsie_gmap_notifier;
 debug_info_t *kvm_s390_dbf;
 
 /* Section: not file related */
@@ -174,6 +181,8 @@ static int kvm_clock_sync(struct notifier_block *notifier, unsigned long val,
                        vcpu->arch.sie_block->epoch -= *delta;
                        if (vcpu->arch.cputm_enabled)
                                vcpu->arch.cputm_start += *delta;
+                       if (vcpu->arch.vsie_block)
+                               vcpu->arch.vsie_block->epoch -= *delta;
                }
        }
        return NOTIFY_OK;
@@ -187,6 +196,8 @@ int kvm_arch_hardware_setup(void)
 {
        gmap_notifier.notifier_call = kvm_gmap_notifier;
        gmap_register_pte_notifier(&gmap_notifier);
+       vsie_gmap_notifier.notifier_call = kvm_s390_vsie_gmap_notifier;
+       gmap_register_pte_notifier(&vsie_gmap_notifier);
        atomic_notifier_chain_register(&s390_epoch_delta_notifier,
                                       &kvm_clock_notifier);
        return 0;
@@ -195,6 +206,7 @@ int kvm_arch_hardware_setup(void)
 void kvm_arch_hardware_unsetup(void)
 {
        gmap_unregister_pte_notifier(&gmap_notifier);
+       gmap_unregister_pte_notifier(&vsie_gmap_notifier);
        atomic_notifier_chain_unregister(&s390_epoch_delta_notifier,
                                         &kvm_clock_notifier);
 }
@@ -252,6 +264,46 @@ static void kvm_s390_cpu_feat_init(void)
 
        if (MACHINE_HAS_ESOP)
                allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP);
+       /*
+        * We need SIE support, ESOP (PROT_READ protection for gmap_shadow),
+        * 64bit SCAO (SCA passthrough) and IDTE (for gmap_shadow unshadowing).
+        */
+       if (!sclp.has_sief2 || !MACHINE_HAS_ESOP || !sclp.has_64bscao ||
+           !test_facility(3) || !nested)
+               return;
+       allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIEF2);
+       if (sclp.has_64bscao)
+               allow_cpu_feat(KVM_S390_VM_CPU_FEAT_64BSCAO);
+       if (sclp.has_siif)
+               allow_cpu_feat(KVM_S390_VM_CPU_FEAT_SIIF);
+       if (sclp.has_gpere)
+               allow_cpu_feat(KVM_S390_VM_CPU_FEAT_GPERE);
+       if (sclp.has_gsls)
+               allow_cpu_feat(KVM_S390_VM_CPU_FEAT_GSLS);
+       if (sclp.has_ib)
+               allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IB);
+       if (sclp.has_cei)
+               allow_cpu_feat(KVM_S390_VM_CPU_FEAT_CEI);
+       if (sclp.has_ibs)
+               allow_cpu_feat(KVM_S390_VM_CPU_FEAT_IBS);
+       /*
+        * KVM_S390_VM_CPU_FEAT_SKEY: Wrong shadow of PTE.I bits will make
+        * all skey handling functions read/set the skey from the PGSTE
+        * instead of the real storage key.
+        *
+        * KVM_S390_VM_CPU_FEAT_CMMA: Wrong shadow of PTE.I bits will make
+        * pages being detected as preserved although they are resident.
+        *
+        * KVM_S390_VM_CPU_FEAT_PFMFI: Wrong shadow of PTE.I bits will
+        * have the same effect as for KVM_S390_VM_CPU_FEAT_SKEY.
+        *
+        * For KVM_S390_VM_CPU_FEAT_SKEY, KVM_S390_VM_CPU_FEAT_CMMA and
+        * KVM_S390_VM_CPU_FEAT_PFMFI, all PTE.I and PGSTE bits have to be
+        * correctly shadowed. We can do that for the PGSTE but not for PTE.I.
+        *
+        * KVM_S390_VM_CPU_FEAT_SIGPIF: Wrong SCB addresses in the SCA. We
+        * cannot easily shadow the SCA because of the ipte lock.
+        */
 }
 
 int kvm_arch_init(void *opaque)
@@ -1406,6 +1458,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
        kvm->arch.epoch = 0;
 
        spin_lock_init(&kvm->arch.start_stop_lock);
+       kvm_s390_vsie_init(kvm);
        KVM_EVENT(3, "vm 0x%pK created by pid %u", kvm, current->pid);
 
        return 0;
@@ -1463,6 +1516,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
                gmap_remove(kvm->arch.gmap);
        kvm_s390_destroy_adapters(kvm);
        kvm_s390_clear_float_irqs(kvm);
+       kvm_s390_vsie_destroy(kvm);
        KVM_EVENT(3, "vm 0x%pK destroyed", kvm);
 }
 
@@ -1719,7 +1773,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 
        save_access_regs(vcpu->arch.host_acrs);
        restore_access_regs(vcpu->run->s.regs.acrs);
-       gmap_enable(vcpu->arch.gmap);
+       gmap_enable(vcpu->arch.enabled_gmap);
        atomic_or(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
        if (vcpu->arch.cputm_enabled && !is_vcpu_idle(vcpu))
                __start_cpu_timer_accounting(vcpu);
@@ -1732,7 +1786,8 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
        if (vcpu->arch.cputm_enabled && !is_vcpu_idle(vcpu))
                __stop_cpu_timer_accounting(vcpu);
        atomic_andnot(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
-       gmap_disable(vcpu->arch.gmap);
+       vcpu->arch.enabled_gmap = gmap_get_enabled();
+       gmap_disable(vcpu->arch.enabled_gmap);
 
        /* Save guest register state */
        save_fpu_regs();
@@ -1781,7 +1836,8 @@ void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
                vcpu->arch.gmap = vcpu->kvm->arch.gmap;
                sca_add_vcpu(vcpu);
        }
-
+       /* make vcpu_load load the right gmap on the first trigger */
+       vcpu->arch.enabled_gmap = vcpu->arch.gmap;
 }
 
 static void kvm_s390_vcpu_crypto_setup(struct kvm_vcpu *vcpu)
@@ -2567,14 +2623,14 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
                 * guest_enter and guest_exit should be no uaccess.
                 */
                local_irq_disable();
-               __kvm_guest_enter();
+               guest_enter_irqoff();
                __disable_cpu_timer_accounting(vcpu);
                local_irq_enable();
                exit_reason = sie64a(vcpu->arch.sie_block,
                                     vcpu->run->s.regs.gprs);
                local_irq_disable();
                __enable_cpu_timer_accounting(vcpu);
-               __kvm_guest_exit();
+               guest_exit_irqoff();
                local_irq_enable();
                vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);