We add ONE_REG interface to enable/disable SBI extensions (just like the ONE_REG interface for ISA extensions). This allows KVM user-space to decide the set of SBI extension enabled for a Guest and by default all SBI extensions are enabled. Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx> --- arch/riscv/include/asm/kvm_vcpu_sbi.h | 8 +- arch/riscv/include/uapi/asm/kvm.h | 20 ++++ arch/riscv/kvm/vcpu.c | 2 + arch/riscv/kvm/vcpu_sbi.c | 150 +++++++++++++++++++++++--- arch/riscv/kvm/vcpu_sbi_base.c | 2 +- 5 files changed, 163 insertions(+), 19 deletions(-) diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h index 8425556af7d1..4278125a38a5 100644 --- a/arch/riscv/include/asm/kvm_vcpu_sbi.h +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h @@ -16,6 +16,7 @@ struct kvm_vcpu_sbi_context { int return_handled; + bool extension_disabled[KVM_RISCV_SBI_EXT_MAX]; }; struct kvm_vcpu_sbi_return { @@ -45,7 +46,12 @@ void kvm_riscv_vcpu_sbi_system_reset(struct kvm_vcpu *vcpu, struct kvm_run *run, u32 type, u64 flags); int kvm_riscv_vcpu_sbi_return(struct kvm_vcpu *vcpu, struct kvm_run *run); -const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(unsigned long extid); +int kvm_riscv_vcpu_set_reg_sbi_ext(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg); +int kvm_riscv_vcpu_get_reg_sbi_ext(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg); +const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext( + struct kvm_vcpu *vcpu, unsigned long extid); int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run); #ifdef CONFIG_RISCV_SBI_V01 diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h index 92af6f3f057c..33c3457b94e7 100644 --- a/arch/riscv/include/uapi/asm/kvm.h +++ b/arch/riscv/include/uapi/asm/kvm.h @@ -108,6 +108,23 @@ enum KVM_RISCV_ISA_EXT_ID { KVM_RISCV_ISA_EXT_MAX, }; +/* + * SBI extension IDs specific to KVM. This is not the same as the SBI + * extension IDs defined by the RISC-V SBI specification. + */ +enum KVM_RISCV_SBI_EXT_ID { + KVM_RISCV_SBI_EXT_V01 = 0, + KVM_RISCV_SBI_EXT_TIME, + KVM_RISCV_SBI_EXT_IPI, + KVM_RISCV_SBI_EXT_RFENCE, + KVM_RISCV_SBI_EXT_SRST, + KVM_RISCV_SBI_EXT_HSM, + KVM_RISCV_SBI_EXT_PMU, + KVM_RISCV_SBI_EXT_EXPERIMENTAL, + KVM_RISCV_SBI_EXT_VENDOR, + KVM_RISCV_SBI_EXT_MAX, +}; + /* Possible states for kvm_riscv_timer */ #define KVM_RISCV_TIMER_STATE_OFF 0 #define KVM_RISCV_TIMER_STATE_ON 1 @@ -152,6 +169,9 @@ enum KVM_RISCV_ISA_EXT_ID { /* ISA Extension registers are mapped as type 7 */ #define KVM_REG_RISCV_ISA_EXT (0x07 << KVM_REG_RISCV_TYPE_SHIFT) +/* SBI extension registers are mapped as type 8 */ +#define KVM_REG_RISCV_SBI_EXT (0x08 << KVM_REG_RISCV_TYPE_SHIFT) + #endif #endif /* __LINUX_KVM_RISCV_H */ diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c index 7d010b0be54e..311fd347c5a8 100644 --- a/arch/riscv/kvm/vcpu.c +++ b/arch/riscv/kvm/vcpu.c @@ -601,6 +601,8 @@ static int kvm_riscv_vcpu_set_reg(struct kvm_vcpu *vcpu, KVM_REG_RISCV_FP_D); case KVM_REG_RISCV_ISA_EXT: return kvm_riscv_vcpu_set_reg_isa_ext(vcpu, reg); + case KVM_REG_RISCV_SBI_EXT: + return kvm_riscv_vcpu_set_reg_sbi_ext(vcpu, reg); default: break; } diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c index 15fde15f9fb8..bedd7d78a5f0 100644 --- a/arch/riscv/kvm/vcpu_sbi.c +++ b/arch/riscv/kvm/vcpu_sbi.c @@ -30,17 +30,52 @@ static const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_pmu = { }; #endif -static const struct kvm_vcpu_sbi_extension *sbi_ext[] = { - &vcpu_sbi_ext_v01, - &vcpu_sbi_ext_base, - &vcpu_sbi_ext_time, - &vcpu_sbi_ext_ipi, - &vcpu_sbi_ext_rfence, - &vcpu_sbi_ext_srst, - &vcpu_sbi_ext_hsm, - &vcpu_sbi_ext_pmu, - &vcpu_sbi_ext_experimental, - &vcpu_sbi_ext_vendor, +struct kvm_riscv_sbi_extension_entry { + enum KVM_RISCV_SBI_EXT_ID dis_idx; + const struct kvm_vcpu_sbi_extension *ext_ptr; +}; + +static const struct kvm_riscv_sbi_extension_entry sbi_ext[] = { + { + .dis_idx = KVM_RISCV_SBI_EXT_V01, + .ext_ptr = &vcpu_sbi_ext_v01, + }, + { + .dis_idx = KVM_RISCV_SBI_EXT_MAX, /* Can't be disabled */ + .ext_ptr = &vcpu_sbi_ext_base, + }, + { + .dis_idx = KVM_RISCV_SBI_EXT_TIME, + .ext_ptr = &vcpu_sbi_ext_time, + }, + { + .dis_idx = KVM_RISCV_SBI_EXT_IPI, + .ext_ptr = &vcpu_sbi_ext_ipi, + }, + { + .dis_idx = KVM_RISCV_SBI_EXT_RFENCE, + .ext_ptr = &vcpu_sbi_ext_rfence, + }, + { + .dis_idx = KVM_RISCV_SBI_EXT_SRST, + .ext_ptr = &vcpu_sbi_ext_srst, + }, + { + .dis_idx = KVM_RISCV_SBI_EXT_HSM, + .ext_ptr = &vcpu_sbi_ext_hsm, + }, + { + .dis_idx = KVM_RISCV_SBI_EXT_PMU, + .ext_ptr = &vcpu_sbi_ext_pmu, + }, + { + .dis_idx = KVM_RISCV_SBI_EXT_EXPERIMENTAL, + .ext_ptr = &vcpu_sbi_ext_experimental, + }, + { + .dis_idx = KVM_RISCV_SBI_EXT_VENDOR, + .ext_ptr = &vcpu_sbi_ext_vendor, + }, }; void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run) @@ -99,14 +134,95 @@ int kvm_riscv_vcpu_sbi_return(struct kvm_vcpu *vcpu, struct kvm_run *run) return 0; } -const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(unsigned long extid) +int kvm_riscv_vcpu_set_reg_sbi_ext(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + KVM_REG_RISCV_SBI_EXT); + unsigned long i, reg_val; + const struct kvm_riscv_sbi_extension_entry *sext = NULL; + struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context; + + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) + return -EINVAL; + + if (copy_from_user(®_val, uaddr, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + if (reg_num >= KVM_RISCV_SBI_EXT_MAX || + (reg_val != 1 && reg_val != 0)) + return -EINVAL; + + if (vcpu->arch.ran_atleast_once) + return -EBUSY; + + for (i = 0; i < ARRAY_SIZE(sbi_ext); i++) { + if (sbi_ext[i].dis_idx == reg_num) { + sext = &sbi_ext[i]; + break; + } + } + if (!sext) + return -ENOENT; + + scontext->extension_disabled[sext->dis_idx] = !reg_val; + + return 0; +} + +int kvm_riscv_vcpu_get_reg_sbi_ext(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + KVM_REG_RISCV_SBI_EXT); + unsigned long i, reg_val; + const struct kvm_riscv_sbi_extension_entry *sext = NULL; + struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context; + + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) + return -EINVAL; + + if (reg_num >= KVM_RISCV_SBI_EXT_MAX) + return -EINVAL; + + for (i = 0; i < ARRAY_SIZE(sbi_ext); i++) { + if (sbi_ext[i].dis_idx == reg_num) { + sext = &sbi_ext[i]; + break; + } + } + if (!sext) + return -ENOENT; + + reg_val = !scontext->extension_disabled[sext->dis_idx]; + if (copy_to_user(uaddr, ®_val, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + return 0; +} + +const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext( + struct kvm_vcpu *vcpu, unsigned long extid) { - int i = 0; + int i; + const struct kvm_riscv_sbi_extension_entry *sext; + struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context; for (i = 0; i < ARRAY_SIZE(sbi_ext); i++) { - if (sbi_ext[i]->extid_start <= extid && - sbi_ext[i]->extid_end >= extid) - return sbi_ext[i]; + sext = &sbi_ext[i]; + if (sext->ext_ptr->extid_start <= extid && + sext->ext_ptr->extid_end >= extid) { + if (sext->dis_idx < KVM_RISCV_SBI_EXT_MAX && + scontext->extension_disabled[sext->dis_idx]) + return NULL; + return sbi_ext[i].ext_ptr; + } } return NULL; @@ -126,7 +242,7 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) }; bool ext_is_v01 = false; - sbi_ext = kvm_vcpu_sbi_find_ext(cp->a7); + sbi_ext = kvm_vcpu_sbi_find_ext(vcpu, cp->a7); if (sbi_ext && sbi_ext->handler) { #ifdef CONFIG_RISCV_SBI_V01 if (cp->a7 >= SBI_EXT_0_1_SET_TIMER && diff --git a/arch/riscv/kvm/vcpu_sbi_base.c b/arch/riscv/kvm/vcpu_sbi_base.c index 9945aff34c14..5bc570b984f4 100644 --- a/arch/riscv/kvm/vcpu_sbi_base.c +++ b/arch/riscv/kvm/vcpu_sbi_base.c @@ -44,7 +44,7 @@ static int kvm_sbi_ext_base_handler(struct kvm_vcpu *vcpu, struct kvm_run *run, kvm_riscv_vcpu_sbi_forward(vcpu, run); retdata->uexit = true; } else { - sbi_ext = kvm_vcpu_sbi_find_ext(cp->a0); + sbi_ext = kvm_vcpu_sbi_find_ext(vcpu, cp->a0); *out_val = sbi_ext && sbi_ext->probe ? sbi_ext->probe(vcpu) : !!sbi_ext; } -- 2.34.1