diff mbox series

[v12,16/31] LoongArch: KVM: Implement update VM id function

Message ID	20230530015223.147755-17-zhaotianrui@loongson.cn
State	New
Headers	Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; From: Tianrui Zhao <zhaotianrui@loongson.cn> To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Paolo Bonzini <pbonzini@redhat.com>, Huacai Chen <chenhuacai@kernel.org>, WANG Xuerui <kernel@xen0n.name>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, loongarch@lists.linux.dev, Jens Axboe <axboe@kernel.dk>, Mark Brown <broonie@kernel.org>, Alex Deucher <alexander.deucher@amd.com>, Oliver Upton <oliver.upton@linux.dev>, maobibo@loongson.cn, Xi Ruoyao <xry111@xry111.site>, zhaotianrui@loongson.cn Subject: [PATCH v12 16/31] LoongArch: KVM: Implement update VM id function Date: Tue, 30 May 2023 09:52:08 +0800 Message-Id: <20230530015223.147755-17-zhaotianrui@loongson.cn> In-Reply-To: <20230530015223.147755-1-zhaotianrui@loongson.cn> References: <20230530015223.147755-1-zhaotianrui@loongson.cn> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	Add KVM LoongArch support \| [v12,00/31] Add KVM LoongArch support [v12,01/31] LoongArch: KVM: Add kvm related header files [v12,02/31] LoongArch: KVM: Implement kvm module related interface [v12,03/31] LoongArch: KVM: Implement kvm hardware enable, disable interface [v12,04/31] LoongArch: KVM: Implement VM related functions [v12,05/31] LoongArch: KVM: Add vcpu related header files [v12,06/31] LoongArch: KVM: Implement vcpu create and destroy interface [v12,07/31] LoongArch: KVM: Implement vcpu run interface [v12,08/31] LoongArch: KVM: Implement vcpu handle exit interface [v12,09/31] LoongArch: KVM: Implement vcpu get, vcpu set registers [v12,10/31] LoongArch: KVM: Implement vcpu ENABLE_CAP ioctl interface [v12,11/31] LoongArch: KVM: Implement fpu related operations for vcpu [v12,12/31] LoongArch: KVM: Implement vcpu interrupt operations [v12,13/31] LoongArch: KVM: Implement misc vcpu related interfaces [v12,14/31] LoongArch: KVM: Implement vcpu load and vcpu put operations [v12,15/31] LoongArch: KVM: Implement vcpu status description [v12,16/31] LoongArch: KVM: Implement update VM id function [v12,17/31] LoongArch: KVM: Implement virtual machine tlb operations [v12,18/31] LoongArch: KVM: Implement vcpu timer operations [v12,19/31] LoongArch: KVM: Implement kvm mmu operations [v12,20/31] LoongArch: KVM: Implement handle csr excption [v12,21/31] LoongArch: KVM: Implement handle iocsr exception [v12,22/31] LoongArch: KVM: Implement handle idle exception [v12,23/31] LoongArch: KVM: Implement handle gspr exception [v12,24/31] LoongArch: KVM: Implement handle mmio exception [v12,25/31] LoongArch: KVM: Implement handle fpu exception [v12,26/31] LoongArch: KVM: Implement kvm exception vector [v12,27/31] LoongArch: KVM: Implement vcpu world switch [v12,28/31] LoongArch: KVM: Implement probe virtualization when LoongArch cpu init [v12,29/31] LoongArch: KVM: Enable kvm config and add the makefile [v12,30/31] LoongArch: KVM: Supplement kvm document about LoongArch-specific part [v12,31/31] LoongArch: KVM: Add maintainers for LoongArch KVM

Commit Message

zhaotianrui May 30, 2023, 1:52 a.m. UTC

  Implement kvm check vmid and update vmid, the vmid should be checked before
vcpu enter guest.

Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
---
 arch/loongarch/kvm/vmid.c | 64 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100644 arch/loongarch/kvm/vmid.c

Comments

maobibo June 6, 2023, 1:13 a.m. UTC | #1

Reviewed-by: Bibo, Mao <maobibo@loongson.cn>

在 2023/5/30 09:52, Tianrui Zhao 写道:
> Implement kvm check vmid and update vmid, the vmid should be checked before
> vcpu enter guest.
> 
> Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
> ---
>  arch/loongarch/kvm/vmid.c | 64 +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 64 insertions(+)
>  create mode 100644 arch/loongarch/kvm/vmid.c
> 
> diff --git a/arch/loongarch/kvm/vmid.c b/arch/loongarch/kvm/vmid.c
> new file mode 100644
> index 000000000000..6fef81b28a48
> --- /dev/null
> +++ b/arch/loongarch/kvm/vmid.c
> @@ -0,0 +1,64 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
> + */
> +
> +#include <linux/kvm_host.h>
> +#include "trace.h"
> +
> +static void _kvm_update_vpid(struct kvm_vcpu *vcpu, int cpu)
> +{
> +	struct kvm_context *context;
> +	unsigned long vpid;
> +
> +	context = per_cpu_ptr(vcpu->kvm->arch.vmcs, cpu);
> +	vpid = context->vpid_cache + 1;
> +	if (!(vpid & vpid_mask)) {
> +		/* finish round of 64 bit loop */
> +		if (unlikely(!vpid))
> +			vpid = vpid_mask + 1;
> +
> +		/* vpid 0 reserved for root */
> +		++vpid;
> +
> +		/* start new vpid cycle */
> +		kvm_flush_tlb_all();
> +	}
> +
> +	context->vpid_cache = vpid;
> +	vcpu->arch.vpid = vpid;
> +}
> +
> +void _kvm_check_vmid(struct kvm_vcpu *vcpu, int cpu)
> +{
> +	struct kvm_context *context;
> +	bool migrated;
> +	unsigned long ver, old, vpid;
> +
> +	/*
> +	 * Are we entering guest context on a different CPU to last time?
> +	 * If so, the vCPU's guest TLB state on this CPU may be stale.
> +	 */
> +	context = per_cpu_ptr(vcpu->kvm->arch.vmcs, cpu);
> +	migrated = (vcpu->arch.last_exec_cpu != cpu);
> +	vcpu->arch.last_exec_cpu = cpu;
> +
> +	/*
> +	 * Check if our vpid is of an older version
> +	 *
> +	 * We also discard the stored vpid if we've executed on
> +	 * another CPU, as the guest mappings may have changed without
> +	 * hypervisor knowledge.
> +	 */
> +	ver = vcpu->arch.vpid & ~vpid_mask;
> +	old = context->vpid_cache  & ~vpid_mask;
> +	if (migrated || (ver != old)) {
> +		_kvm_update_vpid(vcpu, cpu);
> +		trace_kvm_vpid_change(vcpu, vcpu->arch.vpid);
> +	}
> +
> +	/* Restore GSTAT(0x50).vpid */
> +	vpid = (vcpu->arch.vpid & vpid_mask)
> +		<< CSR_GSTAT_GID_SHIFT;
> +	change_csr_gstat(vpid_mask << CSR_GSTAT_GID_SHIFT, vpid);
> +}

diff mbox series

Patch

diff --git a/arch/loongarch/kvm/vmid.c b/arch/loongarch/kvm/vmid.c
new file mode 100644
index 000000000000..6fef81b28a48
--- /dev/null
+++ b/arch/loongarch/kvm/vmid.c
@@ -0,0 +1,64 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
+ */
+
+#include <linux/kvm_host.h>
+#include "trace.h"
+
+static void _kvm_update_vpid(struct kvm_vcpu *vcpu, int cpu)
+{
+	struct kvm_context *context;
+	unsigned long vpid;
+
+	context = per_cpu_ptr(vcpu->kvm->arch.vmcs, cpu);
+	vpid = context->vpid_cache + 1;
+	if (!(vpid & vpid_mask)) {
+		/* finish round of 64 bit loop */
+		if (unlikely(!vpid))
+			vpid = vpid_mask + 1;
+
+		/* vpid 0 reserved for root */
+		++vpid;
+
+		/* start new vpid cycle */
+		kvm_flush_tlb_all();
+	}
+
+	context->vpid_cache = vpid;
+	vcpu->arch.vpid = vpid;
+}
+
+void _kvm_check_vmid(struct kvm_vcpu *vcpu, int cpu)
+{
+	struct kvm_context *context;
+	bool migrated;
+	unsigned long ver, old, vpid;
+
+	/*
+	 * Are we entering guest context on a different CPU to last time?
+	 * If so, the vCPU's guest TLB state on this CPU may be stale.
+	 */
+	context = per_cpu_ptr(vcpu->kvm->arch.vmcs, cpu);
+	migrated = (vcpu->arch.last_exec_cpu != cpu);
+	vcpu->arch.last_exec_cpu = cpu;
+
+	/*
+	 * Check if our vpid is of an older version
+	 *
+	 * We also discard the stored vpid if we've executed on
+	 * another CPU, as the guest mappings may have changed without
+	 * hypervisor knowledge.
+	 */
+	ver = vcpu->arch.vpid & ~vpid_mask;
+	old = context->vpid_cache  & ~vpid_mask;
+	if (migrated || (ver != old)) {
+		_kvm_update_vpid(vcpu, cpu);
+		trace_kvm_vpid_change(vcpu, vcpu->arch.vpid);
+	}
+
+	/* Restore GSTAT(0x50).vpid */
+	vpid = (vcpu->arch.vpid & vpid_mask)
+		<< CSR_GSTAT_GID_SHIFT;
+	change_csr_gstat(vpid_mask << CSR_GSTAT_GID_SHIFT, vpid);
+}