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 thest functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@xxxxxxx> --- arch/riscv/include/asm/kvm_host.h | 70 ++++++++++++++++++++++++++ arch/riscv/kvm/vcpu.c | 83 +++++++++++++++++++++++++++++-- 2 files changed, 149 insertions(+), 4 deletions(-) diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h index 81acfb307d5c..244eabe62710 100644 --- a/arch/riscv/include/asm/kvm_host.h +++ b/arch/riscv/include/asm/kvm_host.h @@ -54,7 +54,77 @@ struct kvm_arch { phys_addr_t pgd_phys; }; +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 hedeleg; + unsigned long hideleg; + unsigned long vsstatus; + unsigned long vsie; + unsigned long vstvec; + unsigned long vsscratch; + unsigned long vsepc; + unsigned long vscause; + unsigned long vstval; + unsigned long vsip; + unsigned long vsatp; +}; + struct kvm_vcpu_arch { + /* VCPU ran atleast 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 9fea9128d964..1ae806f28c0e 100644 --- a/arch/riscv/kvm/vcpu.c +++ b/arch/riscv/kvm/vcpu.c @@ -31,10 +31,48 @@ struct kvm_stats_debugfs_item debugfs_entries[] = { { NULL } }; +#define KVM_RISCV_ISA_ALLOWED (RISCV_ISA_EXT_A | \ + RISCV_ISA_EXT_C | \ + RISCV_ISA_EXT_D | \ + RISCV_ISA_EXT_F | \ + RISCV_ISA_EXT_I | \ + RISCV_ISA_EXT_M | \ + RISCV_ISA_EXT_S | \ + RISCV_ISA_EXT_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)); +} + struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id) { - /* TODO: */ - return NULL; + int err; + struct kvm_vcpu *vcpu; + + vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL); + if (!vcpu) { + err = -ENOMEM; + goto out; + } + + err = kvm_vcpu_init(vcpu, kvm, id); + if (err) + goto free_vcpu; + + return vcpu; + +free_vcpu: + kmem_cache_free(kvm_vcpu_cache, vcpu); +out: + return ERR_PTR(err); } int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu) @@ -48,13 +86,47 @@ void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) { - /* TODO: */ + struct kvm_cpu_context *cntx; + struct kvm_vcpu_csr *csr; + + /* Mark this VCPU never ran */ + vcpu->arch.ran_atleast_once = false; + + /* Setup ISA features available to VCPU */ + vcpu->arch.isa = riscv_isa & 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_SP2V; + cntx->hstatus |= HSTATUS_SP2P; + cntx->hstatus |= HSTATUS_SPV; + + /* Setup reset state of HEDELEG and HIDELEG CSRs */ + csr = &vcpu->arch.guest_reset_csr; + csr->hedeleg = 0; + csr->hedeleg |= (1UL << EXC_INST_MISALIGNED); + csr->hedeleg |= (1UL << EXC_BREAKPOINT); + csr->hedeleg |= (1UL << EXC_SYSCALL); + csr->hedeleg |= (1UL << EXC_INST_PAGE_FAULT); + csr->hedeleg |= (1UL << EXC_LOAD_PAGE_FAULT); + csr->hedeleg |= (1UL << EXC_STORE_PAGE_FAULT); + csr->hideleg = 0; + csr->hideleg |= SIE_SSIE; + csr->hideleg |= SIE_STIE; + csr->hideleg |= SIE_SEIE; + + /* Reset VCPU */ + kvm_riscv_reset_vcpu(vcpu); + return 0; } void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) { - /* TODO: */ + kvm_riscv_stage2_flush_cache(vcpu); + kmem_cache_free(kvm_vcpu_cache, vcpu); } int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) @@ -207,6 +279,9 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) int ret; unsigned long scause, stval; + /* Mark this VCPU ran atleast once */ + vcpu->arch.ran_atleast_once = true; + /* Process MMIO value returned from user-space */ if (run->exit_reason == KVM_EXIT_MMIO) { ret = kvm_riscv_vcpu_mmio_return(vcpu, vcpu->run); -- 2.17.1