[RFC PATCH v4 22/39] KVM: arm64: Add SPE VCPU device attribute to initialize SPE
From: Alexandru Elisei <hidden>
Date: 2021-08-25 16:18:17
Also in:
kvmarm, lkml
Subsystem:
arm64 port (aarch64 architecture), documentation, kernel virtual machine (kvm), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Jonathan Corbet, Paolo Bonzini, Marc Zyngier, Oliver Upton, Linus Torvalds
From: Sudeep Holla <redacted> Add KVM_ARM_VCPU_SPE_CTRL(KVM_ARM_VCPU_SPE_INIT) VCPU ioctl to initialize SPE. Initialization can only be done once for a VCPU. If the feature bit is set, then SPE must be initialized before the VCPU can be run. [ Alexandru E: Split from "KVM: arm64: Add a new VCPU device control group for SPE" ] Signed-off-by: Sudeep Holla <redacted> Signed-off-by: Alexandru Elisei <redacted> --- Documentation/virt/kvm/devices/vcpu.rst | 16 ++++++++++++++ arch/arm64/include/asm/kvm_spe.h | 4 ++-- arch/arm64/include/uapi/asm/kvm.h | 1 + arch/arm64/kvm/arm.c | 7 ++++-- arch/arm64/kvm/spe.c | 29 ++++++++++++++++++++++++- 5 files changed, 52 insertions(+), 5 deletions(-)
diff --git a/Documentation/virt/kvm/devices/vcpu.rst b/Documentation/virt/kvm/devices/vcpu.rst
index 05821d40849f..c275c320e500 100644
--- a/Documentation/virt/kvm/devices/vcpu.rst
+++ b/Documentation/virt/kvm/devices/vcpu.rst@@ -185,3 +185,19 @@ Returns: Specifies the Profiling Buffer management interrupt number. The interrupt number must be a PPI and the interrupt number must be the same for each VCPU. SPE emulation requires an in-kernel vGIC implementation. + +4.2 ATTRIBUTE: KVM_ARM_VCPU_SPE_INIT +----------------------------------- + +:Parameters: no additional parameter in kvm_device_attr.addr + +Returns: + + ======= ============================================ + -EBUSY SPE already initialized for this VCPU + -ENXIO SPE not supported or not properly configured + ======= ============================================ + +Request initialization of the Statistical Profiling Extension for this VCPU. +Must be done after initializaing the in-kernel irqchip and after setting the +Profiling Buffer management interrupt number for the VCPU.
diff --git a/arch/arm64/include/asm/kvm_spe.h b/arch/arm64/include/asm/kvm_spe.h
index 2fe11868719d..2217b821ab37 100644
--- a/arch/arm64/include/asm/kvm_spe.h
+++ b/arch/arm64/include/asm/kvm_spe.h@@ -23,7 +23,7 @@ struct kvm_vcpu_spe { void kvm_spe_init_supported_cpus(void); void kvm_spe_vm_init(struct kvm *kvm); -int kvm_spe_check_supported_cpus(struct kvm_vcpu *vcpu); +int kvm_spe_vcpu_first_run_init(struct kvm_vcpu *vcpu); int kvm_spe_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr); int kvm_spe_get_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr);
@@ -36,7 +36,7 @@ struct kvm_vcpu_spe { static inline void kvm_spe_init_supported_cpus(void) {} static inline void kvm_spe_vm_init(struct kvm *kvm) {} -static inline int kvm_spe_check_supported_cpus(struct kvm_vcpu *vcpu) { return -ENOEXEC; } +static inline int kvm_spe_vcpu_first_run_init(struct kvm_vcpu *vcpu) { return -ENOEXEC; } static inline int kvm_spe_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index c55d94a1a8f5..d4c0b53a5fb2 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h@@ -370,6 +370,7 @@ struct kvm_arm_copy_mte_tags { #define KVM_ARM_VCPU_PVTIME_IPA 0 #define KVM_ARM_VCPU_SPE_CTRL 3 #define KVM_ARM_VCPU_SPE_IRQ 0 +#define KVM_ARM_VCPU_SPE_INIT 1 /* KVM_IRQ_LINE irq field index values */ #define KVM_ARM_IRQ_VCPU2_SHIFT 28
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 8f7025f2e4a0..6af7ef26d2c1 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c@@ -633,8 +633,11 @@ static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) if (!kvm_arm_vcpu_is_finalized(vcpu)) return -EPERM; - if (kvm_vcpu_has_spe(vcpu) && kvm_spe_check_supported_cpus(vcpu)) - return -EPERM; + if (kvm_vcpu_has_spe(vcpu)) { + ret = kvm_spe_vcpu_first_run_init(vcpu); + if (ret) + return ret; + } vcpu->arch.has_run_once = true;
diff --git a/arch/arm64/kvm/spe.c b/arch/arm64/kvm/spe.c
index 2fdb42e27675..801ceb66a3d0 100644
--- a/arch/arm64/kvm/spe.c
+++ b/arch/arm64/kvm/spe.c@@ -31,7 +31,7 @@ void kvm_spe_vm_init(struct kvm *kvm) kvm_spe_init_supported_cpus(); } -int kvm_spe_check_supported_cpus(struct kvm_vcpu *vcpu) +static int kvm_spe_check_supported_cpus(struct kvm_vcpu *vcpu) { /* SPE is supported on all CPUs, we don't care about the VCPU mask */ if (cpumask_equal(supported_cpus, cpu_possible_mask))
@@ -43,6 +43,20 @@ int kvm_spe_check_supported_cpus(struct kvm_vcpu *vcpu) return 0; } +int kvm_spe_vcpu_first_run_init(struct kvm_vcpu *vcpu) +{ + int ret; + + ret = kvm_spe_check_supported_cpus(vcpu); + if (ret) + return ret; + + if (!vcpu->arch.spe.initialized) + return -EPERM; + + return 0; +} + static bool kvm_vcpu_supports_spe(struct kvm_vcpu *vcpu) { if (!kvm_supports_spe())
@@ -102,6 +116,18 @@ int kvm_spe_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) vcpu->arch.spe.irq_num = irq; return 0; } + case KVM_ARM_VCPU_SPE_INIT: + if (!vcpu->arch.spe.irq_num) + return -ENXIO; + + if (!vgic_initialized(vcpu->kvm)) + return -ENXIO; + + if (kvm_vgic_set_owner(vcpu, vcpu->arch.spe.irq_num, &vcpu->arch.spe)) + return -ENXIO; + + vcpu->arch.spe.initialized = true; + return 0; } return -ENXIO;
@@ -138,6 +164,7 @@ int kvm_spe_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) switch(attr->attr) { case KVM_ARM_VCPU_SPE_IRQ: + case KVM_ARM_VCPU_SPE_INIT: return 0; }
--
2.33.0
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