diff mbox series

[v18,16/30] LoongArch: KVM: Implement update VM id function

Message ID	20230803022138.2736430-17-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 v18 16/30] LoongArch: KVM: Implement update VM id function Date: Thu, 3 Aug 2023 10:21:24 +0800 Message-Id: <20230803022138.2736430-17-zhaotianrui@loongson.cn> In-Reply-To: <20230803022138.2736430-1-zhaotianrui@loongson.cn> References: <20230803022138.2736430-1-zhaotianrui@loongson.cn> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	Add KVM LoongArch support \| [v18,00/30] Add KVM LoongArch support [v18,01/30] LoongArch: KVM: Add kvm related header files [v18,02/30] LoongArch: KVM: Implement kvm module related interface [v18,03/30] LoongArch: KVM: Implement kvm hardware enable, disable interface [v18,04/30] LoongArch: KVM: Implement VM related functions [v18,05/30] LoongArch: KVM: Add vcpu related header files [v18,06/30] LoongArch: KVM: Implement vcpu create and destroy interface [v18,07/30] LoongArch: KVM: Implement vcpu run interface [v18,08/30] LoongArch: KVM: Implement vcpu handle exit interface [v18,09/30] LoongArch: KVM: Implement vcpu get, vcpu set registers [v18,10/30] LoongArch: KVM: Implement vcpu ENABLE_CAP ioctl interface [v18,11/30] LoongArch: KVM: Implement fpu related operations for vcpu [v18,12/30] LoongArch: KVM: Implement vcpu interrupt operations [v18,13/30] LoongArch: KVM: Implement misc vcpu related interfaces [v18,14/30] LoongArch: KVM: Implement vcpu load and vcpu put operations [v18,15/30] LoongArch: KVM: Implement vcpu status description [v18,16/30] LoongArch: KVM: Implement update VM id function [v18,17/30] LoongArch: KVM: Implement virtual machine tlb operations [v18,18/30] LoongArch: KVM: Implement vcpu timer operations [v18,19/30] LoongArch: KVM: Implement kvm mmu operations [v18,20/30] LoongArch: KVM: Implement handle csr excption [v18,21/30] LoongArch: KVM: Implement handle iocsr exception [v18,22/30] LoongArch: KVM: Implement handle idle exception [v18,23/30] LoongArch: KVM: Implement handle gspr exception [v18,24/30] LoongArch: KVM: Implement handle mmio exception [v18,25/30] LoongArch: KVM: Implement handle fpu exception [v18,26/30] LoongArch: KVM: Implement kvm exception vector [v18,27/30] LoongArch: KVM: Implement vcpu world switch [v18,28/30] LoongArch: KVM: Enable kvm config and add the makefile [v18,29/30] LoongArch: KVM: Supplement kvm document about LoongArch-specific part [v18,30/30] LoongArch: KVM: Add maintainers for LoongArch KVM

Commit Message

zhaotianrui Aug. 3, 2023, 2:21 a.m. UTC

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

Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
---
 arch/loongarch/kvm/vmid.c | 66 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)
 create mode 100644 arch/loongarch/kvm/vmid.c

diff mbox series

Patch

diff --git a/arch/loongarch/kvm/vmid.c b/arch/loongarch/kvm/vmid.c
new file mode 100644
index 000000000000..fc25ddc3b74a
--- /dev/null
+++ b/arch/loongarch/kvm/vmid.c
@@ -0,0 +1,66 @@ 
+// 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)
+{
+	struct kvm_context *context;
+	bool migrated;
+	unsigned long ver, old, vpid;
+	int cpu;
+
+	cpu = smp_processor_id();
+	/*
+	 * 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->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);
+		vcpu->cpu = cpu;
+	}
+
+	/* Restore GSTAT(0x50).vpid */
+	vpid = (vcpu->arch.vpid & vpid_mask)
+		<< CSR_GSTAT_GID_SHIFT;
+	change_csr_gstat(vpid_mask << CSR_GSTAT_GID_SHIFT, vpid);
+}