[PATCH v18 03/18] RISC-V: KVM: Implement VCPU create, init and destroy functions
Anup Patel
anup.patel at wdc.com
Tue May 18 20:35:38 PDT 2021
This patch implements VCPU create, init and destroy functions
required by generic KVM module. We don't have much dynamic
resources in struct kvm_vcpu_arch so these functions are quite
simple for KVM RISC-V.
Signed-off-by: Anup Patel <anup.patel at wdc.com>
Acked-by: Paolo Bonzini <pbonzini at redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini at redhat.com>
Reviewed-by: Alexander Graf <graf at amazon.com>
---
arch/riscv/include/asm/kvm_host.h | 69 +++++++++++++++++++++++++++++++
arch/riscv/kvm/vcpu.c | 55 ++++++++++++++++++++----
2 files changed, 115 insertions(+), 9 deletions(-)
diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h
index 2068475bd168..cf2a23bbd560 100644
--- a/arch/riscv/include/asm/kvm_host.h
+++ b/arch/riscv/include/asm/kvm_host.h
@@ -62,7 +62,76 @@ struct kvm_cpu_trap {
unsigned long htinst;
};
+struct kvm_cpu_context {
+ unsigned long zero;
+ unsigned long ra;
+ unsigned long sp;
+ unsigned long gp;
+ unsigned long tp;
+ unsigned long t0;
+ unsigned long t1;
+ unsigned long t2;
+ unsigned long s0;
+ unsigned long s1;
+ unsigned long a0;
+ unsigned long a1;
+ unsigned long a2;
+ unsigned long a3;
+ unsigned long a4;
+ unsigned long a5;
+ unsigned long a6;
+ unsigned long a7;
+ unsigned long s2;
+ unsigned long s3;
+ unsigned long s4;
+ unsigned long s5;
+ unsigned long s6;
+ unsigned long s7;
+ unsigned long s8;
+ unsigned long s9;
+ unsigned long s10;
+ unsigned long s11;
+ unsigned long t3;
+ unsigned long t4;
+ unsigned long t5;
+ unsigned long t6;
+ unsigned long sepc;
+ unsigned long sstatus;
+ unsigned long hstatus;
+};
+
+struct kvm_vcpu_csr {
+ unsigned long vsstatus;
+ unsigned long hie;
+ unsigned long vstvec;
+ unsigned long vsscratch;
+ unsigned long vsepc;
+ unsigned long vscause;
+ unsigned long vstval;
+ unsigned long hvip;
+ unsigned long vsatp;
+ unsigned long scounteren;
+};
+
struct kvm_vcpu_arch {
+ /* VCPU ran at least once */
+ bool ran_atleast_once;
+
+ /* ISA feature bits (similar to MISA) */
+ unsigned long isa;
+
+ /* CPU context of Guest VCPU */
+ struct kvm_cpu_context guest_context;
+
+ /* CPU CSR context of Guest VCPU */
+ struct kvm_vcpu_csr guest_csr;
+
+ /* CPU context upon Guest VCPU reset */
+ struct kvm_cpu_context guest_reset_context;
+
+ /* CPU CSR context upon Guest VCPU reset */
+ struct kvm_vcpu_csr guest_reset_csr;
+
/* Don't run the VCPU (blocked) */
bool pause;
diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c
index d76cecf93de4..904d908a7544 100644
--- a/arch/riscv/kvm/vcpu.c
+++ b/arch/riscv/kvm/vcpu.c
@@ -35,6 +35,27 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
{ NULL }
};
+#define KVM_RISCV_ISA_ALLOWED (riscv_isa_extension_mask(a) | \
+ riscv_isa_extension_mask(c) | \
+ riscv_isa_extension_mask(d) | \
+ riscv_isa_extension_mask(f) | \
+ riscv_isa_extension_mask(i) | \
+ riscv_isa_extension_mask(m) | \
+ riscv_isa_extension_mask(s) | \
+ riscv_isa_extension_mask(u))
+
+static void kvm_riscv_reset_vcpu(struct kvm_vcpu *vcpu)
+{
+ struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
+ struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr;
+ struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
+ struct kvm_cpu_context *reset_cntx = &vcpu->arch.guest_reset_context;
+
+ memcpy(csr, reset_csr, sizeof(*csr));
+
+ memcpy(cntx, reset_cntx, sizeof(*cntx));
+}
+
int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
{
return 0;
@@ -42,7 +63,25 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
{
- /* TODO: */
+ struct kvm_cpu_context *cntx;
+
+ /* Mark this VCPU never ran */
+ vcpu->arch.ran_atleast_once = false;
+
+ /* Setup ISA features available to VCPU */
+ vcpu->arch.isa = riscv_isa_extension_base(NULL) & KVM_RISCV_ISA_ALLOWED;
+
+ /* Setup reset state of shadow SSTATUS and HSTATUS CSRs */
+ cntx = &vcpu->arch.guest_reset_context;
+ cntx->sstatus = SR_SPP | SR_SPIE;
+ cntx->hstatus = 0;
+ cntx->hstatus |= HSTATUS_VTW;
+ cntx->hstatus |= HSTATUS_SPVP;
+ cntx->hstatus |= HSTATUS_SPV;
+
+ /* Reset VCPU */
+ kvm_riscv_reset_vcpu(vcpu);
+
return 0;
}
@@ -50,15 +89,10 @@ void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
{
}
-int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
-{
- /* TODO: */
- return 0;
-}
-
void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
{
- /* TODO: */
+ /* Flush the pages pre-allocated for Stage2 page table mappings */
+ kvm_riscv_stage2_flush_cache(vcpu);
}
int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
@@ -194,6 +228,9 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
struct kvm_cpu_trap trap;
struct kvm_run *run = vcpu->run;
+ /* Mark this VCPU ran at least once */
+ vcpu->arch.ran_atleast_once = true;
+
vcpu->arch.srcu_idx = srcu_read_lock(&vcpu->kvm->srcu);
/* Process MMIO value returned from user-space */
@@ -267,7 +304,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
* get an interrupt between __kvm_riscv_switch_to() and
* local_irq_enable() which can potentially change CSRs.
*/
- trap.sepc = 0;
+ trap.sepc = vcpu->arch.guest_context.sepc;
trap.scause = csr_read(CSR_SCAUSE);
trap.stval = csr_read(CSR_STVAL);
trap.htval = csr_read(CSR_HTVAL);
--
2.25.1
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