[PATCH v4 2/5] RISC-V: KVM: Reorganize SBI code by moving SBI v0.1 to its own file
Anup Patel
anup at brainfault.org
Fri Nov 5 21:43:35 PDT 2021
On Sat, Nov 6, 2021 at 5:29 AM Atish Patra <atish.patra at wdc.com> wrote:
>
> With SBI v0.2, there may be more SBI extensions in future. It makes more
> sense to group related extensions in separate files. Guest kernel will
> choose appropriate SBI version dynamically.
>
> Move the existing implementation to a separate file so that it can be
> removed in future without much conflict.
>
> Signed-off-by: Atish Patra <atish.patra at wdc.com>
> ---
> arch/riscv/include/asm/kvm_vcpu_sbi.h | 2 +
> arch/riscv/kvm/Makefile | 1 +
> arch/riscv/kvm/vcpu_sbi.c | 151 +++-----------------------
> arch/riscv/kvm/vcpu_sbi_v01.c | 129 ++++++++++++++++++++++
> 4 files changed, 149 insertions(+), 134 deletions(-)
> create mode 100644 arch/riscv/kvm/vcpu_sbi_v01.c
>
> diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h
> index 1a4cb0db2d0b..704151969ceb 100644
> --- a/arch/riscv/include/asm/kvm_vcpu_sbi.h
> +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h
> @@ -25,5 +25,7 @@ struct kvm_vcpu_sbi_extension {
> bool *exit);
> };
>
> +void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run);
> const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(unsigned long extid);
> +
> #endif /* __RISCV_KVM_VCPU_SBI_H__ */
> diff --git a/arch/riscv/kvm/Makefile b/arch/riscv/kvm/Makefile
> index 30cdd1df0098..d3d5ff3a6019 100644
> --- a/arch/riscv/kvm/Makefile
> +++ b/arch/riscv/kvm/Makefile
> @@ -23,4 +23,5 @@ kvm-y += vcpu_exit.o
> kvm-y += vcpu_fp.o
> kvm-y += vcpu_switch.o
> kvm-y += vcpu_sbi.o
> +kvm-$(CONFIG_RISCV_SBI_V01) += vcpu_sbi_v01.o
> kvm-y += vcpu_timer.o
> diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c
> index 05cab5f27eee..06b42f6977e1 100644
> --- a/arch/riscv/kvm/vcpu_sbi.c
> +++ b/arch/riscv/kvm/vcpu_sbi.c
> @@ -9,9 +9,7 @@
> #include <linux/errno.h>
> #include <linux/err.h>
> #include <linux/kvm_host.h>
> -#include <asm/csr.h>
> #include <asm/sbi.h>
> -#include <asm/kvm_vcpu_timer.h>
> #include <asm/kvm_vcpu_sbi.h>
>
> static int kvm_linux_err_map_sbi(int err)
> @@ -32,8 +30,21 @@ static int kvm_linux_err_map_sbi(int err)
> };
> }
>
> -static void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu,
> - struct kvm_run *run)
> +#ifdef CONFIG_RISCV_SBI_V01
> +extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01;
> +#else
> +static const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01 = {
> + .extid_start = -1UL,
> + .extid_end = -1UL,
> + .handler = NULL,
> +};
> +#endif
> +
> +static const struct kvm_vcpu_sbi_extension *sbi_ext[] = {
> + &vcpu_sbi_ext_v01,
> +};
> +
> +void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run)
> {
> struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
>
> @@ -71,126 +82,6 @@ int kvm_riscv_vcpu_sbi_return(struct kvm_vcpu *vcpu, struct kvm_run *run)
> return 0;
> }
>
> -#ifdef CONFIG_RISCV_SBI_V01
> -
> -static void kvm_sbi_system_shutdown(struct kvm_vcpu *vcpu,
> - struct kvm_run *run, u32 type)
> -{
> - int i;
> - struct kvm_vcpu *tmp;
> -
> - kvm_for_each_vcpu(i, tmp, vcpu->kvm)
> - tmp->arch.power_off = true;
> - kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_SLEEP);
> -
> - memset(&run->system_event, 0, sizeof(run->system_event));
> - run->system_event.type = type;
> - run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
> -}
> -
> -static int kvm_sbi_ext_v01_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
> - unsigned long *out_val,
> - struct kvm_cpu_trap *utrap,
> - bool *exit)
> -{
> - ulong hmask;
> - int i, ret = 0;
> - u64 next_cycle;
> - struct kvm_vcpu *rvcpu;
> - struct cpumask cm, hm;
> - struct kvm *kvm = vcpu->kvm;
> - struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
> -
> - if (!cp)
> - return -EINVAL;
> -
> - switch (cp->a7) {
> - case SBI_EXT_0_1_CONSOLE_GETCHAR:
> - case SBI_EXT_0_1_CONSOLE_PUTCHAR:
> - /*
> - * The CONSOLE_GETCHAR/CONSOLE_PUTCHAR SBI calls cannot be
> - * handled in kernel so we forward these to user-space
> - */
> - kvm_riscv_vcpu_sbi_forward(vcpu, run);
> - *exit = true;
> - break;
> - case SBI_EXT_0_1_SET_TIMER:
> -#if __riscv_xlen == 32
> - next_cycle = ((u64)cp->a1 << 32) | (u64)cp->a0;
> -#else
> - next_cycle = (u64)cp->a0;
> -#endif
> - ret = kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle);
> - break;
> - case SBI_EXT_0_1_CLEAR_IPI:
> - ret = kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_SOFT);
> - break;
> - case SBI_EXT_0_1_SEND_IPI:
> - if (cp->a0)
> - hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0,
> - utrap);
> - else
> - hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1;
> - if (utrap->scause)
> - break;
> -
> - for_each_set_bit(i, &hmask, BITS_PER_LONG) {
> - rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i);
> - ret = kvm_riscv_vcpu_set_interrupt(rvcpu, IRQ_VS_SOFT);
> - if (ret < 0)
> - break;
> - }
> - break;
> - case SBI_EXT_0_1_SHUTDOWN:
> - kvm_sbi_system_shutdown(vcpu, run, KVM_SYSTEM_EVENT_SHUTDOWN);
> - *exit = true;
> - break;
> - case SBI_EXT_0_1_REMOTE_FENCE_I:
> - case SBI_EXT_0_1_REMOTE_SFENCE_VMA:
> - case SBI_EXT_0_1_REMOTE_SFENCE_VMA_ASID:
> - if (cp->a0)
> - hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0,
> - utrap);
> - else
> - hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1;
> - if (utrap->scause)
> - break;
> -
> - cpumask_clear(&cm);
> - for_each_set_bit(i, &hmask, BITS_PER_LONG) {
> - rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i);
> - if (rvcpu->cpu < 0)
> - continue;
> - cpumask_set_cpu(rvcpu->cpu, &cm);
> - }
> - riscv_cpuid_to_hartid_mask(&cm, &hm);
> - if (cp->a7 == SBI_EXT_0_1_REMOTE_FENCE_I)
> - ret = sbi_remote_fence_i(cpumask_bits(&hm));
> - else if (cp->a7 == SBI_EXT_0_1_REMOTE_SFENCE_VMA)
> - ret = sbi_remote_hfence_vvma(cpumask_bits(&hm),
> - cp->a1, cp->a2);
> - else
> - ret = sbi_remote_hfence_vvma_asid(cpumask_bits(&hm),
> - cp->a1, cp->a2, cp->a3);
> - break;
> - default:
> - ret = -EINVAL;
> - break;
> - }
> -
> - return ret;
> -}
> -
> -const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01 = {
> - .extid_start = SBI_EXT_0_1_SET_TIMER,
> - .extid_end = SBI_EXT_0_1_SHUTDOWN,
> - .handler = kvm_sbi_ext_v01_handler,
> -};
> -
> -static const struct kvm_vcpu_sbi_extension *sbi_ext[] = {
> - &vcpu_sbi_ext_v01,
> -};
> -
> const struct kvm_vcpu_sbi_extension *kvm_vcpu_sbi_find_ext(unsigned long extid)
> {
> int i = 0;
> @@ -220,9 +111,11 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run)
>
> sbi_ext = kvm_vcpu_sbi_find_ext(cp->a7);
> if (sbi_ext && sbi_ext->handler) {
> +#ifdef CONFIG_RISCV_SBI_V01
> if (cp->a7 >= SBI_EXT_0_1_SET_TIMER &&
> cp->a7 <= SBI_EXT_0_1_SHUTDOWN)
> ext_is_v01 = true;
> +#endif
> ret = sbi_ext->handler(vcpu, run, &out_val, &utrap, &userspace_exit);
> } else {
> /* Return error for unsupported SBI calls */
> @@ -262,13 +155,3 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run)
>
> return ret;
> }
> -
> -#else
> -
> -int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run)
> -{
> - kvm_riscv_vcpu_sbi_forward(vcpu, run);
> - return 0;
> -}
> -
> -#endif
> diff --git a/arch/riscv/kvm/vcpu_sbi_v01.c b/arch/riscv/kvm/vcpu_sbi_v01.c
> new file mode 100644
> index 000000000000..5a8e2afc8a57
> --- /dev/null
> +++ b/arch/riscv/kvm/vcpu_sbi_v01.c
> @@ -0,0 +1,129 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2021 Western Digital Corporation or its affiliates.
> + *
> + * Authors:
> + * Atish Patra <atish.patra at wdc.com>
> + */
> +
> +#include <linux/errno.h>
> +#include <linux/err.h>
> +#include <linux/kvm_host.h>
> +#include <asm/csr.h>
> +#include <asm/sbi.h>
> +#include <asm/kvm_vcpu_timer.h>
> +#include <asm/kvm_vcpu_sbi.h>
> +
> +static void kvm_sbi_system_shutdown(struct kvm_vcpu *vcpu,
> + struct kvm_run *run, u32 type)
> +{
> + int i;
> + struct kvm_vcpu *tmp;
> +
> + kvm_for_each_vcpu(i, tmp, vcpu->kvm)
> + tmp->arch.power_off = true;
> + kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_SLEEP);
> +
> + memset(&run->system_event, 0, sizeof(run->system_event));
> + run->system_event.type = type;
> + run->exit_reason = KVM_EXIT_SYSTEM_EVENT;
> +}
> +
> +static int kvm_sbi_ext_v01_handler(struct kvm_vcpu *vcpu, struct kvm_run *run,
> + unsigned long *out_val,
> + struct kvm_cpu_trap *utrap,
> + bool *exit)
> +{
> + ulong hmask;
> + int i, ret = 0;
> + u64 next_cycle;
> + struct kvm_vcpu *rvcpu;
> + struct cpumask cm, hm;
> + struct kvm *kvm = vcpu->kvm;
> + struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
> +
> + if (!cp)
> + return -EINVAL;
This check on "cp" is unnecessary.
> +
> + switch (cp->a7) {
> + case SBI_EXT_0_1_CONSOLE_GETCHAR:
> + case SBI_EXT_0_1_CONSOLE_PUTCHAR:
> + /*
> + * The CONSOLE_GETCHAR/CONSOLE_PUTCHAR SBI calls cannot be
> + * handled in kernel so we forward these to user-space
> + */
> + kvm_riscv_vcpu_sbi_forward(vcpu, run);
> + *exit = true;
> + break;
> + case SBI_EXT_0_1_SET_TIMER:
> +#if __riscv_xlen == 32
> + next_cycle = ((u64)cp->a1 << 32) | (u64)cp->a0;
> +#else
> + next_cycle = (u64)cp->a0;
> +#endif
> + ret = kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle);
> + break;
> + case SBI_EXT_0_1_CLEAR_IPI:
> + ret = kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_SOFT);
> + break;
> + case SBI_EXT_0_1_SEND_IPI:
> + if (cp->a0)
> + hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0,
> + utrap);
> + else
> + hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1;
> + if (utrap->scause)
> + break;
> +
> + for_each_set_bit(i, &hmask, BITS_PER_LONG) {
> + rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i);
> + ret = kvm_riscv_vcpu_set_interrupt(rvcpu, IRQ_VS_SOFT);
> + if (ret < 0)
> + break;
> + }
> + break;
> + case SBI_EXT_0_1_SHUTDOWN:
> + kvm_sbi_system_shutdown(vcpu, run, KVM_SYSTEM_EVENT_SHUTDOWN);
> + *exit = true;
> + break;
> + case SBI_EXT_0_1_REMOTE_FENCE_I:
> + case SBI_EXT_0_1_REMOTE_SFENCE_VMA:
> + case SBI_EXT_0_1_REMOTE_SFENCE_VMA_ASID:
> + if (cp->a0)
> + hmask = kvm_riscv_vcpu_unpriv_read(vcpu, false, cp->a0,
> + utrap);
> + else
> + hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1;
> + if (utrap->scause)
> + break;
> +
> + cpumask_clear(&cm);
> + for_each_set_bit(i, &hmask, BITS_PER_LONG) {
> + rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i);
> + if (rvcpu->cpu < 0)
> + continue;
> + cpumask_set_cpu(rvcpu->cpu, &cm);
> + }
> + riscv_cpuid_to_hartid_mask(&cm, &hm);
> + if (cp->a7 == SBI_EXT_0_1_REMOTE_FENCE_I)
> + ret = sbi_remote_fence_i(cpumask_bits(&hm));
> + else if (cp->a7 == SBI_EXT_0_1_REMOTE_SFENCE_VMA)
> + ret = sbi_remote_hfence_vvma(cpumask_bits(&hm),
> + cp->a1, cp->a2);
> + else
> + ret = sbi_remote_hfence_vvma_asid(cpumask_bits(&hm),
> + cp->a1, cp->a2, cp->a3);
> + break;
> + default:
> + ret = -EINVAL;
> + break;
> + };
> +
> + return ret;
> +}
> +
> +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_v01 = {
> + .extid_start = SBI_EXT_0_1_SET_TIMER,
> + .extid_end = SBI_EXT_0_1_SHUTDOWN,
> + .handler = kvm_sbi_ext_v01_handler,
> +};
> --
> 2.31.1
>
Otherwise it looks good to me.
Reviewed-by: Anup Patel <anup.patel at wdc.com>
Regards,
Anup
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