On Fri, Mar 31, 2023 at 11:15:42PM +0530, Anup Patel wrote: > 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 | 32 ++++ > arch/riscv/kvm/vcpu.c | 4 + > arch/riscv/kvm/vcpu_sbi.c | 247 ++++++++++++++++++++++++-- > arch/riscv/kvm/vcpu_sbi_base.c | 2 +- > 5 files changed, 274 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..d8ead5952ed9 100644 > --- a/arch/riscv/include/uapi/asm/kvm.h > +++ b/arch/riscv/include/uapi/asm/kvm.h > @@ -12,6 +12,7 @@ > #ifndef __ASSEMBLY__ > > #include <linux/types.h> > +#include <asm/bitsperlong.h> > #include <asm/ptrace.h> > > #define __KVM_HAVE_READONLY_MEM > @@ -108,6 +109,23 @@ 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 > @@ -118,6 +136,8 @@ enum KVM_RISCV_ISA_EXT_ID { > /* If you need to interpret the index values, here is the key: */ > #define KVM_REG_RISCV_TYPE_MASK 0x00000000FF000000 > #define KVM_REG_RISCV_TYPE_SHIFT 24 > +#define KVM_REG_RISCV_SUBTYPE_MASK 0x0000000000FF0000 > +#define KVM_REG_RISCV_SUBTYPE_SHIFT 16 > > /* Config registers are mapped as type 1 */ > #define KVM_REG_RISCV_CONFIG (0x01 << KVM_REG_RISCV_TYPE_SHIFT) > @@ -152,6 +172,18 @@ 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) > +#define KVM_REG_RISCV_SBI_SINGLE (0x0 << KVM_REG_RISCV_SUBTYPE_SHIFT) > +#define KVM_REG_RISCV_SBI_MULTI_EN (0x1 << KVM_REG_RISCV_SUBTYPE_SHIFT) > +#define KVM_REG_RISCV_SBI_MULTI_DIS (0x2 << KVM_REG_RISCV_SUBTYPE_SHIFT) > +#define KVM_REG_RISCV_SBI_MULTI_REG(__ext_id) \ > + ((__ext_id) / __BITS_PER_LONG) > +#define KVM_REG_RISCV_SBI_MULTI_MASK(__ext_id) \ > + (1UL << ((__ext_id) % __BITS_PER_LONG)) > +#define KVM_REG_RISCV_SBI_MULTI_REG_LAST \ > + KVM_REG_RISCV_SBI_MULTI_REG(KVM_RISCV_SBI_EXT_MAX - 1) > + > #endif > > #endif /* __LINUX_KVM_RISCV_H */ > diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c > index 7d010b0be54e..3112697cb12d 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; > } > @@ -628,6 +630,8 @@ static int kvm_riscv_vcpu_get_reg(struct kvm_vcpu *vcpu, > KVM_REG_RISCV_FP_D); > case KVM_REG_RISCV_ISA_EXT: > return kvm_riscv_vcpu_get_reg_isa_ext(vcpu, reg); > + case KVM_REG_RISCV_SBI_EXT: > + return kvm_riscv_vcpu_get_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..223f34c63ea1 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 +134,192 @@ 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) > +static int riscv_vcpu_set_sbi_ext_single(struct kvm_vcpu *vcpu, > + unsigned long reg_num, > + unsigned long reg_val) > +{ > + unsigned long i; > + const struct kvm_riscv_sbi_extension_entry *sext = NULL; > + struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context; > + > + if (reg_num >= KVM_RISCV_SBI_EXT_MAX || > + (reg_val != 1 && reg_val != 0)) > + 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; > + > + scontext->extension_disabled[sext->dis_idx] = !reg_val; > + > + return 0; > +} > + > +static int riscv_vcpu_get_sbi_ext_single(struct kvm_vcpu *vcpu, > + unsigned long reg_num, > + unsigned long *reg_val) > +{ > + unsigned long i; > + const struct kvm_riscv_sbi_extension_entry *sext = NULL; > + struct kvm_vcpu_sbi_context *scontext = &vcpu->arch.sbi_context; > + > + 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]; > + > + return 0; > +} > + > +static int riscv_vcpu_set_sbi_ext_multi(struct kvm_vcpu *vcpu, > + unsigned long reg_num, > + unsigned long reg_val, bool enable) > +{ > + unsigned long i, ext_id; > + > + if (reg_num > KVM_REG_RISCV_SBI_MULTI_REG_LAST) > + return -EINVAL; > + > + for_each_set_bit(i, ®_val, BITS_PER_LONG) { > + ext_id = i + reg_num * BITS_PER_LONG; > + if (ext_id >= KVM_RISCV_SBI_EXT_MAX) > + break; > + > + riscv_vcpu_set_sbi_ext_single(vcpu, ext_id, enable); > + } > + > + return 0; > +} > + > +static int riscv_vcpu_get_sbi_ext_multi(struct kvm_vcpu *vcpu, > + unsigned long reg_num, > + unsigned long *reg_val) > +{ > + unsigned long i, ext_id, ext_val; > + > + if (reg_num > KVM_REG_RISCV_SBI_MULTI_REG_LAST) > + return -EINVAL; > + > + for (i = 0; i < BITS_PER_LONG; i++) { > + ext_id = i + reg_num * BITS_PER_LONG; > + if (ext_id >= KVM_RISCV_SBI_EXT_MAX) > + break; > + > + ext_val = 0; > + riscv_vcpu_get_sbi_ext_single(vcpu, ext_id, &ext_val); > + if (ext_val) > + *reg_val |= KVM_REG_RISCV_SBI_MULTI_MASK(ext_id); > + } > + > + return 0; > +} > + > +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 reg_val, reg_subtype; > + > + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) > + return -EINVAL; > + > + if (vcpu->arch.ran_atleast_once) > + return -EBUSY; > + > + reg_subtype = reg_num & KVM_REG_RISCV_SUBTYPE_MASK; > + reg_num &= ~KVM_REG_RISCV_SUBTYPE_MASK; > + > + if (copy_from_user(®_val, uaddr, KVM_REG_SIZE(reg->id))) > + return -EFAULT; > + > + switch (reg_subtype) { > + case KVM_REG_RISCV_SBI_SINGLE: > + return riscv_vcpu_set_sbi_ext_single(vcpu, reg_num, reg_val); > + case KVM_REG_RISCV_SBI_MULTI_EN: > + return riscv_vcpu_set_sbi_ext_multi(vcpu, reg_num, reg_val, true); > + case KVM_REG_RISCV_SBI_MULTI_DIS: > + return riscv_vcpu_set_sbi_ext_multi(vcpu, reg_num, reg_val, false); > + default: > + return -EINVAL; > + }; ^ unnecessary ; > + > + return 0; > +} > + > +int kvm_riscv_vcpu_get_reg_sbi_ext(struct kvm_vcpu *vcpu, > + const struct kvm_one_reg *reg) > +{ > + int rc; > + 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 reg_val, reg_subtype; > + > + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) > + return -EINVAL; > + > + reg_subtype = reg_num & KVM_REG_RISCV_SUBTYPE_MASK; > + reg_num &= ~KVM_REG_RISCV_SUBTYPE_MASK; > + > + reg_val = 0; > + switch (reg_subtype) { > + case KVM_REG_RISCV_SBI_SINGLE: > + rc = riscv_vcpu_get_sbi_ext_single(vcpu, reg_num, ®_val); > + break; > + case KVM_REG_RISCV_SBI_MULTI_EN: > + case KVM_REG_RISCV_SBI_MULTI_DIS: > + rc = riscv_vcpu_get_sbi_ext_multi(vcpu, reg_num, ®_val); > + if (!rc && reg_subtype == KVM_REG_RISCV_SBI_MULTI_DIS) > + reg_val = ~reg_val; > + break; > + default: > + rc = -EINVAL; > + }; ^ unnecessary ; > + if (rc) > + return rc; > + > + 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 +339,7 @@ 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 > Other than the ;'s Reviewed-by: Andrew Jones <ajones@xxxxxxxxxxxxxxxx> Thanks, drew