diff mbox series

[v7,16/30] LoongArch: KVM: Implement update VM id function

Message ID 20230417094649.874671-17-zhaotianrui@loongson.cn
State New
Headers
Series Add KVM LoongArch support |

Commit Message

zhaotianrui April 17, 2023, 9:46 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 | 65 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 65 insertions(+)
 create mode 100644 arch/loongarch/kvm/vmid.c

Comments

Huacai Chen April 19, 2023, 2:01 a.m. UTC | #1 
Hi, Tianrui,

On Mon, Apr 17, 2023 at 5:47 PM Tianrui Zhao <zhaotianrui@loongson.cn> wrote:
>
> 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 | 65 +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 65 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..7d9688c24184
> --- /dev/null
> +++ b/arch/loongarch/kvm/vmid.c
> @@ -0,0 +1,65 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
> + */
> +
> +#include <linux/kvm_host.h>
> +#include <asm/kvm_host.h>
linux/kvm_host.h already include asm/kvm_host.h

Huacai
> +#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);
> +}
> --
> 2.31.1
>
zhaotianrui April 19, 2023, 8:53 a.m. UTC | #2 
在 2023年04月19日 10:01, Huacai Chen 写道:
> Hi, Tianrui,
>
> On Mon, Apr 17, 2023 at 5:47 PM Tianrui Zhao <zhaotianrui@loongson.cn> wrote:
>> 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 | 65 +++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 65 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..7d9688c24184
>> --- /dev/null
>> +++ b/arch/loongarch/kvm/vmid.c
>> @@ -0,0 +1,65 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
>> + */
>> +
>> +#include <linux/kvm_host.h>
>> +#include <asm/kvm_host.h>
> linux/kvm_host.h already include asm/kvm_host.h
>
> Huacai
Thanks, I will remove the asm/kvm_host.h.

Thanks
Tianrui Zhao
>> +#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);
>> +}
>> --
>> 2.31.1
>>
diff mbox series

Patch

diff --git a/arch/loongarch/kvm/vmid.c b/arch/loongarch/kvm/vmid.c
new file mode 100644
index 000000000000..7d9688c24184
--- /dev/null
+++ b/arch/loongarch/kvm/vmid.c
@@ -0,0 +1,65 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
+ */
+
+#include <linux/kvm_host.h>
+#include <asm/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);
+}