| Message ID | 20211118083912.981995-2-atishp@rivosinc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add SBI v0.2 support for KVM | expand |
On Thu, Nov 18, 2021 at 2:10 PM Atish Patra <atishp@rivosinc.com> wrote: > > From: Atish Patra <atish.patra@wdc.com> > > The existing SBI specification impelementation follows v0.1 > specification. The latest specification allows more > scalability and performance improvements. > > Rename the existing implementation as v01 and provide a way to allow > future extensions. > > Reviewed-by: Anup Patel <anup.patel@wdc.com> > Signed-off-by: Atish Patra <atish.patra@wdc.com> > Signed-off-by: Atish Patra <atishp@rivosinc.com> I have queued this for 5.17 Thanks, Anup > --- > arch/riscv/include/asm/kvm_vcpu_sbi.h | 29 +++++ > arch/riscv/kvm/vcpu_sbi.c | 149 ++++++++++++++++++++------ > 2 files changed, 145 insertions(+), 33 deletions(-) > create mode 100644 arch/riscv/include/asm/kvm_vcpu_sbi.h > > diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h > new file mode 100644 > index 000000000000..1a4cb0db2d0b > --- /dev/null > +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h > @@ -0,0 +1,29 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/** > + * Copyright (c) 2021 Western Digital Corporation or its affiliates. > + * > + * Authors: > + * Atish Patra <atish.patra@wdc.com> > + */ > + > +#ifndef __RISCV_KVM_VCPU_SBI_H__ > +#define __RISCV_KVM_VCPU_SBI_H__ > + > +#define KVM_SBI_VERSION_MAJOR 0 > +#define KVM_SBI_VERSION_MINOR 2 > + > +struct kvm_vcpu_sbi_extension { > + unsigned long extid_start; > + unsigned long extid_end; > + /** > + * SBI extension handler. It can be defined for a given extension or group of > + * extension. But it should always return linux error codes rather than SBI > + * specific error codes. > + */ > + int (*handler)(struct kvm_vcpu *vcpu, struct kvm_run *run, > + unsigned long *out_val, struct kvm_cpu_trap *utrap, > + bool *exit); > +}; > + > +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/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c > index eb3c045edf11..32376906ff20 100644 > --- a/arch/riscv/kvm/vcpu_sbi.c > +++ b/arch/riscv/kvm/vcpu_sbi.c > @@ -1,5 +1,5 @@ > // SPDX-License-Identifier: GPL-2.0 > -/** > +/* > * Copyright (c) 2019 Western Digital Corporation or its affiliates. > * > * Authors: > @@ -12,9 +12,25 @@ > #include <asm/csr.h> > #include <asm/sbi.h> > #include <asm/kvm_vcpu_timer.h> > +#include <asm/kvm_vcpu_sbi.h> > > -#define SBI_VERSION_MAJOR 0 > -#define SBI_VERSION_MINOR 1 > +static int kvm_linux_err_map_sbi(int err) > +{ > + switch (err) { > + case 0: > + return SBI_SUCCESS; > + case -EPERM: > + return SBI_ERR_DENIED; > + case -EINVAL: > + return SBI_ERR_INVALID_PARAM; > + case -EFAULT: > + return SBI_ERR_INVALID_ADDRESS; > + case -EOPNOTSUPP: > + return SBI_ERR_NOT_SUPPORTED; > + default: > + return SBI_ERR_FAILURE; > + }; > +} > > static void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, > struct kvm_run *run) > @@ -72,21 +88,19 @@ static void kvm_sbi_system_shutdown(struct kvm_vcpu *vcpu, > run->exit_reason = KVM_EXIT_SYSTEM_EVENT; > } > > -int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) > +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 = 1; > + int i, ret = 0; > u64 next_cycle; > struct kvm_vcpu *rvcpu; > - bool next_sepc = true; > struct cpumask cm, hm; > struct kvm *kvm = vcpu->kvm; > - struct kvm_cpu_trap utrap = { 0 }; > 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: > @@ -95,8 +109,7 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) > * handled in kernel so we forward these to user-space > */ > kvm_riscv_vcpu_sbi_forward(vcpu, run); > - next_sepc = false; > - ret = 0; > + *exit = true; > break; > case SBI_EXT_0_1_SET_TIMER: > #if __riscv_xlen == 32 > @@ -104,47 +117,42 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) > #else > next_cycle = (u64)cp->a0; > #endif > - kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle); > + ret = kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle); > break; > case SBI_EXT_0_1_CLEAR_IPI: > - kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_SOFT); > + 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); > + utrap); > else > hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1; > - if (utrap.scause) { > - utrap.sepc = cp->sepc; > - kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); > - next_sepc = false; > + if (utrap->scause) > break; > - } > + > for_each_set_bit(i, &hmask, BITS_PER_LONG) { > rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i); > - kvm_riscv_vcpu_set_interrupt(rvcpu, IRQ_VS_SOFT); > + 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); > - next_sepc = false; > - ret = 0; > + *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); > + utrap); > else > hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1; > - if (utrap.scause) { > - utrap.sepc = cp->sepc; > - kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); > - next_sepc = false; > + 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); > @@ -154,22 +162,97 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) > } > riscv_cpuid_to_hartid_mask(&cm, &hm); > if (cp->a7 == SBI_EXT_0_1_REMOTE_FENCE_I) > - sbi_remote_fence_i(cpumask_bits(&hm)); > + ret = sbi_remote_fence_i(cpumask_bits(&hm)); > else if (cp->a7 == SBI_EXT_0_1_REMOTE_SFENCE_VMA) > - sbi_remote_hfence_vvma(cpumask_bits(&hm), > + ret = sbi_remote_hfence_vvma(cpumask_bits(&hm), > cp->a1, cp->a2); > else > - sbi_remote_hfence_vvma_asid(cpumask_bits(&hm), > + 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; > + > + 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]; > + } > + > + return NULL; > +} > + > +int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) > +{ > + int ret = 1; > + bool next_sepc = true; > + bool userspace_exit = false; > + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; > + const struct kvm_vcpu_sbi_extension *sbi_ext; > + struct kvm_cpu_trap utrap = { 0 }; > + unsigned long out_val = 0; > + bool ext_is_v01 = false; > + > + sbi_ext = kvm_vcpu_sbi_find_ext(cp->a7); > + if (sbi_ext && sbi_ext->handler) { > + if (cp->a7 >= SBI_EXT_0_1_SET_TIMER && > + cp->a7 <= SBI_EXT_0_1_SHUTDOWN) > + ext_is_v01 = true; > + ret = sbi_ext->handler(vcpu, run, &out_val, &utrap, &userspace_exit); > + } else { > /* Return error for unsupported SBI calls */ > cp->a0 = SBI_ERR_NOT_SUPPORTED; > - break; > + goto ecall_done; > + } > + > + /* Handle special error cases i.e trap, exit or userspace forward */ > + if (utrap.scause) { > + /* No need to increment sepc or exit ioctl loop */ > + ret = 1; > + utrap.sepc = cp->sepc; > + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); > + next_sepc = false; > + goto ecall_done; > } > > + /* Exit ioctl loop or Propagate the error code the guest */ > + if (userspace_exit) { > + next_sepc = false; > + ret = 0; > + } else { > + /** > + * SBI extension handler always returns an Linux error code. Convert > + * it to the SBI specific error code that can be propagated the SBI > + * caller. > + */ > + ret = kvm_linux_err_map_sbi(ret); > + cp->a0 = ret; > + ret = 1; > + } > +ecall_done: > if (next_sepc) > cp->sepc += 4; > + if (!ext_is_v01) > + cp->a1 = out_val; > > return ret; > } > -- > 2.33.1 > > > -- > kvm-riscv mailing list > kvm-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/kvm-riscv
Hi Atish, Am Donnerstag, 18. November 2021, 09:39:08 CET schrieb Atish Patra: > From: Atish Patra <atish.patra@wdc.com> > > The existing SBI specification impelementation follows v0.1 > specification. The latest specification allows more > scalability and performance improvements. > > Rename the existing implementation as v01 and provide a way to allow > future extensions. > > Reviewed-by: Anup Patel <anup.patel@wdc.com> > Signed-off-by: Atish Patra <atish.patra@wdc.com> > Signed-off-by: Atish Patra <atishp@rivosinc.com> > --- > diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c > index eb3c045edf11..32376906ff20 100644 > --- a/arch/riscv/kvm/vcpu_sbi.c > +++ b/arch/riscv/kvm/vcpu_sbi.c > @@ -1,5 +1,5 @@ > // SPDX-License-Identifier: GPL-2.0 > -/** > +/* > * Copyright (c) 2019 Western Digital Corporation or its affiliates. > * > * Authors: This got already fixed by [0] commit 0e2e64192100 ("riscv: kvm: fix non-kernel-doc comment block") so this patch doesn't apply cleanly anymore. This looks like it is a prerequisite for the sparse-hart-id series, so a respin might be in order. Heiko [0] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0e2e641921000ffc647b12918cdfcc504a9f6e3b > @@ -12,9 +12,25 @@ > #include <asm/csr.h> > #include <asm/sbi.h> > #include <asm/kvm_vcpu_timer.h> > +#include <asm/kvm_vcpu_sbi.h> > > -#define SBI_VERSION_MAJOR 0 > -#define SBI_VERSION_MINOR 1 > +static int kvm_linux_err_map_sbi(int err) > +{ > + switch (err) { > + case 0: > + return SBI_SUCCESS; > + case -EPERM: > + return SBI_ERR_DENIED; > + case -EINVAL: > + return SBI_ERR_INVALID_PARAM; > + case -EFAULT: > + return SBI_ERR_INVALID_ADDRESS; > + case -EOPNOTSUPP: > + return SBI_ERR_NOT_SUPPORTED; > + default: > + return SBI_ERR_FAILURE; > + }; > +} > > static void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, > struct kvm_run *run) > @@ -72,21 +88,19 @@ static void kvm_sbi_system_shutdown(struct kvm_vcpu *vcpu, > run->exit_reason = KVM_EXIT_SYSTEM_EVENT; > } > > -int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) > +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 = 1; > + int i, ret = 0; > u64 next_cycle; > struct kvm_vcpu *rvcpu; > - bool next_sepc = true; > struct cpumask cm, hm; > struct kvm *kvm = vcpu->kvm; > - struct kvm_cpu_trap utrap = { 0 }; > 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: > @@ -95,8 +109,7 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) > * handled in kernel so we forward these to user-space > */ > kvm_riscv_vcpu_sbi_forward(vcpu, run); > - next_sepc = false; > - ret = 0; > + *exit = true; > break; > case SBI_EXT_0_1_SET_TIMER: > #if __riscv_xlen == 32 > @@ -104,47 +117,42 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) > #else > next_cycle = (u64)cp->a0; > #endif > - kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle); > + ret = kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle); > break; > case SBI_EXT_0_1_CLEAR_IPI: > - kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_SOFT); > + 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); > + utrap); > else > hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1; > - if (utrap.scause) { > - utrap.sepc = cp->sepc; > - kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); > - next_sepc = false; > + if (utrap->scause) > break; > - } > + > for_each_set_bit(i, &hmask, BITS_PER_LONG) { > rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i); > - kvm_riscv_vcpu_set_interrupt(rvcpu, IRQ_VS_SOFT); > + 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); > - next_sepc = false; > - ret = 0; > + *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); > + utrap); > else > hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1; > - if (utrap.scause) { > - utrap.sepc = cp->sepc; > - kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); > - next_sepc = false; > + 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); > @@ -154,22 +162,97 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) > } > riscv_cpuid_to_hartid_mask(&cm, &hm); > if (cp->a7 == SBI_EXT_0_1_REMOTE_FENCE_I) > - sbi_remote_fence_i(cpumask_bits(&hm)); > + ret = sbi_remote_fence_i(cpumask_bits(&hm)); > else if (cp->a7 == SBI_EXT_0_1_REMOTE_SFENCE_VMA) > - sbi_remote_hfence_vvma(cpumask_bits(&hm), > + ret = sbi_remote_hfence_vvma(cpumask_bits(&hm), > cp->a1, cp->a2); > else > - sbi_remote_hfence_vvma_asid(cpumask_bits(&hm), > + 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; > + > + 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]; > + } > + > + return NULL; > +} > + > +int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) > +{ > + int ret = 1; > + bool next_sepc = true; > + bool userspace_exit = false; > + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; > + const struct kvm_vcpu_sbi_extension *sbi_ext; > + struct kvm_cpu_trap utrap = { 0 }; > + unsigned long out_val = 0; > + bool ext_is_v01 = false; > + > + sbi_ext = kvm_vcpu_sbi_find_ext(cp->a7); > + if (sbi_ext && sbi_ext->handler) { > + if (cp->a7 >= SBI_EXT_0_1_SET_TIMER && > + cp->a7 <= SBI_EXT_0_1_SHUTDOWN) > + ext_is_v01 = true; > + ret = sbi_ext->handler(vcpu, run, &out_val, &utrap, &userspace_exit); > + } else { > /* Return error for unsupported SBI calls */ > cp->a0 = SBI_ERR_NOT_SUPPORTED; > - break; > + goto ecall_done; > + } > + > + /* Handle special error cases i.e trap, exit or userspace forward */ > + if (utrap.scause) { > + /* No need to increment sepc or exit ioctl loop */ > + ret = 1; > + utrap.sepc = cp->sepc; > + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); > + next_sepc = false; > + goto ecall_done; > } > > + /* Exit ioctl loop or Propagate the error code the guest */ > + if (userspace_exit) { > + next_sepc = false; > + ret = 0; > + } else { > + /** > + * SBI extension handler always returns an Linux error code. Convert > + * it to the SBI specific error code that can be propagated the SBI > + * caller. > + */ > + ret = kvm_linux_err_map_sbi(ret); > + cp->a0 = ret; > + ret = 1; > + } > +ecall_done: > if (next_sepc) > cp->sepc += 4; > + if (!ext_is_v01) > + cp->a1 = out_val; > > return ret; > } >
Am Dienstag, 4. Januar 2022, 14:19:41 CET schrieb Heiko Stübner: > Hi Atish, > > Am Donnerstag, 18. November 2021, 09:39:08 CET schrieb Atish Patra: > > From: Atish Patra <atish.patra@wdc.com> > > > > The existing SBI specification impelementation follows v0.1 > > specification. The latest specification allows more > > scalability and performance improvements. > > > > Rename the existing implementation as v01 and provide a way to allow > > future extensions. > > > > Reviewed-by: Anup Patel <anup.patel@wdc.com> > > Signed-off-by: Atish Patra <atish.patra@wdc.com> > > Signed-off-by: Atish Patra <atishp@rivosinc.com> > > --- > > > diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c > > index eb3c045edf11..32376906ff20 100644 > > --- a/arch/riscv/kvm/vcpu_sbi.c > > +++ b/arch/riscv/kvm/vcpu_sbi.c > > @@ -1,5 +1,5 @@ > > // SPDX-License-Identifier: GPL-2.0 > > -/** > > +/* > > * Copyright (c) 2019 Western Digital Corporation or its affiliates. > > * > > * Authors: > > This got already fixed by [0] > commit 0e2e64192100 ("riscv: kvm: fix non-kernel-doc comment block") > so this patch doesn't apply cleanly anymore. hmm, just found Anup's "I've queued this..." message after writing my reply, so scratch the above ;-) . @Anup: I've looked at git.kernel.org but didn't find a tree there, can you tell me where this did go to? Thanks Heiko
On Tue, Jan 4, 2022 at 6:57 PM Heiko Stübner <heiko@sntech.de> wrote: > > Am Dienstag, 4. Januar 2022, 14:19:41 CET schrieb Heiko Stübner: > > Hi Atish, > > > > Am Donnerstag, 18. November 2021, 09:39:08 CET schrieb Atish Patra: > > > From: Atish Patra <atish.patra@wdc.com> > > > > > > The existing SBI specification impelementation follows v0.1 > > > specification. The latest specification allows more > > > scalability and performance improvements. > > > > > > Rename the existing implementation as v01 and provide a way to allow > > > future extensions. > > > > > > Reviewed-by: Anup Patel <anup.patel@wdc.com> > > > Signed-off-by: Atish Patra <atish.patra@wdc.com> > > > Signed-off-by: Atish Patra <atishp@rivosinc.com> > > > --- > > > > > diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c > > > index eb3c045edf11..32376906ff20 100644 > > > --- a/arch/riscv/kvm/vcpu_sbi.c > > > +++ b/arch/riscv/kvm/vcpu_sbi.c > > > @@ -1,5 +1,5 @@ > > > // SPDX-License-Identifier: GPL-2.0 > > > -/** > > > +/* > > > * Copyright (c) 2019 Western Digital Corporation or its affiliates. > > > * > > > * Authors: > > > > This got already fixed by [0] > > commit 0e2e64192100 ("riscv: kvm: fix non-kernel-doc comment block") > > so this patch doesn't apply cleanly anymore. > > hmm, just found Anup's "I've queued this..." message after > writing my reply, so scratch the above ;-) . > > @Anup: I've looked at git.kernel.org but didn't find a tree > there, can you tell me where this did go to? All queued patches are in riscv_kvm_queue branch of the KVM RISC-V tree at https://github.com/kvm-riscv/linux.git Regards, Anup > > Thanks > Heiko > >
diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h new file mode 100644 index 000000000000..1a4cb0db2d0b --- /dev/null +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h @@ -0,0 +1,29 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/** + * Copyright (c) 2021 Western Digital Corporation or its affiliates. + * + * Authors: + * Atish Patra <atish.patra@wdc.com> + */ + +#ifndef __RISCV_KVM_VCPU_SBI_H__ +#define __RISCV_KVM_VCPU_SBI_H__ + +#define KVM_SBI_VERSION_MAJOR 0 +#define KVM_SBI_VERSION_MINOR 2 + +struct kvm_vcpu_sbi_extension { + unsigned long extid_start; + unsigned long extid_end; + /** + * SBI extension handler. It can be defined for a given extension or group of + * extension. But it should always return linux error codes rather than SBI + * specific error codes. + */ + int (*handler)(struct kvm_vcpu *vcpu, struct kvm_run *run, + unsigned long *out_val, struct kvm_cpu_trap *utrap, + bool *exit); +}; + +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/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c index eb3c045edf11..32376906ff20 100644 --- a/arch/riscv/kvm/vcpu_sbi.c +++ b/arch/riscv/kvm/vcpu_sbi.c @@ -1,5 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 -/** +/* * Copyright (c) 2019 Western Digital Corporation or its affiliates. * * Authors: @@ -12,9 +12,25 @@ #include <asm/csr.h> #include <asm/sbi.h> #include <asm/kvm_vcpu_timer.h> +#include <asm/kvm_vcpu_sbi.h> -#define SBI_VERSION_MAJOR 0 -#define SBI_VERSION_MINOR 1 +static int kvm_linux_err_map_sbi(int err) +{ + switch (err) { + case 0: + return SBI_SUCCESS; + case -EPERM: + return SBI_ERR_DENIED; + case -EINVAL: + return SBI_ERR_INVALID_PARAM; + case -EFAULT: + return SBI_ERR_INVALID_ADDRESS; + case -EOPNOTSUPP: + return SBI_ERR_NOT_SUPPORTED; + default: + return SBI_ERR_FAILURE; + }; +} static void kvm_riscv_vcpu_sbi_forward(struct kvm_vcpu *vcpu, struct kvm_run *run) @@ -72,21 +88,19 @@ static void kvm_sbi_system_shutdown(struct kvm_vcpu *vcpu, run->exit_reason = KVM_EXIT_SYSTEM_EVENT; } -int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) +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 = 1; + int i, ret = 0; u64 next_cycle; struct kvm_vcpu *rvcpu; - bool next_sepc = true; struct cpumask cm, hm; struct kvm *kvm = vcpu->kvm; - struct kvm_cpu_trap utrap = { 0 }; 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: @@ -95,8 +109,7 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) * handled in kernel so we forward these to user-space */ kvm_riscv_vcpu_sbi_forward(vcpu, run); - next_sepc = false; - ret = 0; + *exit = true; break; case SBI_EXT_0_1_SET_TIMER: #if __riscv_xlen == 32 @@ -104,47 +117,42 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) #else next_cycle = (u64)cp->a0; #endif - kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle); + ret = kvm_riscv_vcpu_timer_next_event(vcpu, next_cycle); break; case SBI_EXT_0_1_CLEAR_IPI: - kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_SOFT); + 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); + utrap); else hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1; - if (utrap.scause) { - utrap.sepc = cp->sepc; - kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); - next_sepc = false; + if (utrap->scause) break; - } + for_each_set_bit(i, &hmask, BITS_PER_LONG) { rvcpu = kvm_get_vcpu_by_id(vcpu->kvm, i); - kvm_riscv_vcpu_set_interrupt(rvcpu, IRQ_VS_SOFT); + 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); - next_sepc = false; - ret = 0; + *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); + utrap); else hmask = (1UL << atomic_read(&kvm->online_vcpus)) - 1; - if (utrap.scause) { - utrap.sepc = cp->sepc; - kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); - next_sepc = false; + 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); @@ -154,22 +162,97 @@ int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) } riscv_cpuid_to_hartid_mask(&cm, &hm); if (cp->a7 == SBI_EXT_0_1_REMOTE_FENCE_I) - sbi_remote_fence_i(cpumask_bits(&hm)); + ret = sbi_remote_fence_i(cpumask_bits(&hm)); else if (cp->a7 == SBI_EXT_0_1_REMOTE_SFENCE_VMA) - sbi_remote_hfence_vvma(cpumask_bits(&hm), + ret = sbi_remote_hfence_vvma(cpumask_bits(&hm), cp->a1, cp->a2); else - sbi_remote_hfence_vvma_asid(cpumask_bits(&hm), + 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; + + 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]; + } + + return NULL; +} + +int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + int ret = 1; + bool next_sepc = true; + bool userspace_exit = false; + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + const struct kvm_vcpu_sbi_extension *sbi_ext; + struct kvm_cpu_trap utrap = { 0 }; + unsigned long out_val = 0; + bool ext_is_v01 = false; + + sbi_ext = kvm_vcpu_sbi_find_ext(cp->a7); + if (sbi_ext && sbi_ext->handler) { + if (cp->a7 >= SBI_EXT_0_1_SET_TIMER && + cp->a7 <= SBI_EXT_0_1_SHUTDOWN) + ext_is_v01 = true; + ret = sbi_ext->handler(vcpu, run, &out_val, &utrap, &userspace_exit); + } else { /* Return error for unsupported SBI calls */ cp->a0 = SBI_ERR_NOT_SUPPORTED; - break; + goto ecall_done; + } + + /* Handle special error cases i.e trap, exit or userspace forward */ + if (utrap.scause) { + /* No need to increment sepc or exit ioctl loop */ + ret = 1; + utrap.sepc = cp->sepc; + kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); + next_sepc = false; + goto ecall_done; } + /* Exit ioctl loop or Propagate the error code the guest */ + if (userspace_exit) { + next_sepc = false; + ret = 0; + } else { + /** + * SBI extension handler always returns an Linux error code. Convert + * it to the SBI specific error code that can be propagated the SBI + * caller. + */ + ret = kvm_linux_err_map_sbi(ret); + cp->a0 = ret; + ret = 1; + } +ecall_done: if (next_sepc) cp->sepc += 4; + if (!ext_is_v01) + cp->a1 = out_val; return ret; }