From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Jones Date: Fri, 21 Jul 2023 11:04:46 +0200 Subject: [PATCH v2 5/6] RISCV: KVM: Add sstateen0 context save/restore In-Reply-To: <20230721075439.454473-6-mchitale@ventanamicro.com> References: <20230721075439.454473-1-mchitale@ventanamicro.com> <20230721075439.454473-6-mchitale@ventanamicro.com> Message-ID: <20230721-78d78a037c03f7a75c5e6525@orel> List-Id: To: kvm-riscv@lists.infradead.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Fri, Jul 21, 2023 at 01:24:38PM +0530, Mayuresh Chitale wrote: > Define sstateen0 and add sstateen0 save/restore for guest VCPUs. > > Signed-off-by: Mayuresh Chitale > --- > arch/riscv/include/asm/csr.h | 1 + > arch/riscv/include/asm/kvm_host.h | 8 ++++++++ > arch/riscv/kvm/vcpu.c | 10 ++++++++++ > 3 files changed, 19 insertions(+) > > diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h > index b52270278733..5168f37d8e75 100644 > --- a/arch/riscv/include/asm/csr.h > +++ b/arch/riscv/include/asm/csr.h > @@ -286,6 +286,7 @@ > #define CSR_STVEC 0x105 > #define CSR_SCOUNTEREN 0x106 > #define CSR_SENVCFG 0x10a > +#define CSR_SSTATEEN0 0x10c > #define CSR_SSCRATCH 0x140 > #define CSR_SEPC 0x141 > #define CSR_SCAUSE 0x142 > diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h > index c3cc0cb39cf8..c9837772b109 100644 > --- a/arch/riscv/include/asm/kvm_host.h > +++ b/arch/riscv/include/asm/kvm_host.h > @@ -170,6 +170,10 @@ struct kvm_vcpu_config { > u64 hstateen0; > }; > > +struct kvm_vcpu_smstateen_csr { > + unsigned long sstateen0; > +}; > + > struct kvm_vcpu_arch { > /* VCPU ran at least once */ > bool ran_atleast_once; > @@ -190,6 +194,7 @@ struct kvm_vcpu_arch { > unsigned long host_stvec; > unsigned long host_scounteren; > unsigned long host_senvcfg; > + unsigned long host_sstateen0; > > /* CPU context of Host */ > struct kvm_cpu_context host_context; > @@ -200,6 +205,9 @@ struct kvm_vcpu_arch { > /* CPU CSR context of Guest VCPU */ > struct kvm_vcpu_csr guest_csr; > > + /* CPU Smstateen CSR context of Guest VCPU */ > + struct kvm_vcpu_smstateen_csr smstateen_csr; > + > /* CPU context upon Guest VCPU reset */ > struct kvm_cpu_context guest_reset_context; > > diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c > index 37f1ed70d782..ae750decbefe 100644 > --- a/arch/riscv/kvm/vcpu.c > +++ b/arch/riscv/kvm/vcpu.c > @@ -1138,14 +1138,24 @@ static void kvm_riscv_update_hvip(struct kvm_vcpu *vcpu) > */ > static void noinstr kvm_riscv_vcpu_enter_exit(struct kvm_vcpu *vcpu) > { > + struct kvm_vcpu_smstateen_csr *smcsr = &vcpu->arch.smstateen_csr; > struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; > + struct kvm_vcpu_config *cfg = &vcpu->arch.cfg; > > vcpu->arch.host_senvcfg = csr_swap(CSR_SENVCFG, csr->senvcfg); > + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN) && > + (cfg->hstateen0 & SMSTATEEN0_SSTATEEN0)) > + vcpu->arch.host_sstateen0 = csr_swap(CSR_SSTATEEN0, > + smcsr->sstateen0); > guest_state_enter_irqoff(); > __kvm_riscv_switch_to(&vcpu->arch); > vcpu->arch.last_exit_cpu = vcpu->cpu; > guest_state_exit_irqoff(); > csr->senvcfg = csr_swap(CSR_SENVCFG, vcpu->arch.host_senvcfg); > + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN) && > + (cfg->hstateen0 & SMSTATEEN0_SSTATEEN0)) > + smcsr->sstateen0 = csr_swap(CSR_SSTATEEN0, > + vcpu->arch.host_sstateen0); > } It might be nice to keep kvm_riscv_vcpu_enter_exit() "clean", by adding a couple functions. Something like static __always_inline void kvm_riscv_vcpu_swap_in_guest_state(struct kvm_vcpu *vcpu) { struct kvm_vcpu_smstateen_csr *smcsr = &vcpu->arch.smstateen_csr; struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; struct kvm_vcpu_config *cfg = &vcpu->arch.cfg; vcpu->arch.host_senvcfg = csr_swap(CSR_SENVCFG, csr->senvcfg); if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN) && (cfg->hstateen0 & SMSTATEEN0_SSTATEEN0)) vcpu->arch.host_sstateen0 = csr_swap(CSR_SSTATEEN0, smcsr->sstateen0); } static __always_inline void kvm_riscv_vcpu_swap_in_host_state(struct kvm_vcpu *vcpu) { struct kvm_vcpu_smstateen_csr *smcsr = &vcpu->arch.smstateen_csr; struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; struct kvm_vcpu_config *cfg = &vcpu->arch.cfg; csr->senvcfg = csr_swap(CSR_SENVCFG, vcpu->arch.host_senvcfg); if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN) && (cfg->hstateen0 & SMSTATEEN0_SSTATEEN0)) smcsr->sstateen0 = csr_swap(CSR_SSTATEEN0, vcpu->arch.host_sstateen0); } static void noinstr kvm_riscv_vcpu_enter_exit(struct kvm_vcpu *vcpu) { kvm_riscv_vcpu_swap_in_guest_state(vcpu); guest_state_enter_irqoff(); __kvm_riscv_switch_to(&vcpu->arch); vcpu->arch.last_exit_cpu = vcpu->cpu; guest_state_exit_irqoff(); kvm_riscv_vcpu_swap_in_host_state(vcpu); } > > int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) > -- > 2.34.1 > Either way, Reviewed-by: Andrew Jones Thanks, drew