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linux/arch/riscv/kvm/vcpu.c

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RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2019 Western Digital Corporation or its affiliates.
*
* Authors:
* Anup Patel <anup.patel@wdc.com>
*/
#include <linux/bitops.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kdebug.h>
#include <linux/module.h>
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
#include <linux/percpu.h>
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
#include <linux/sched/signal.h>
#include <linux/fs.h>
#include <linux/kvm_host.h>
#include <asm/csr.h>
#include <asm/hwcap.h>
const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = {
KVM_GENERIC_VCPU_STATS(),
STATS_DESC_COUNTER(VCPU, ecall_exit_stat),
STATS_DESC_COUNTER(VCPU, wfi_exit_stat),
STATS_DESC_COUNTER(VCPU, mmio_exit_user),
STATS_DESC_COUNTER(VCPU, mmio_exit_kernel),
RISC-V: KVM: Add extensible CSR emulation framework We add an extensible CSR emulation framework which is based upon the existing system instruction emulation. This will be useful to upcoming AIA, PMU, Nested and other virtualization features. The CSR emulation framework also has provision to emulate CSR in user space but this will be used only in very specific cases such as AIA IMSIC CSR emulation in user space or vendor specific CSR emulation in user space. By default, all CSRs not handled by KVM RISC-V will be redirected back to Guest VCPU as illegal instruction trap. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:53 +05:30
STATS_DESC_COUNTER(VCPU, csr_exit_user),
STATS_DESC_COUNTER(VCPU, csr_exit_kernel),
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
STATS_DESC_COUNTER(VCPU, exits)
};
const struct kvm_stats_header kvm_vcpu_stats_header = {
.name_size = KVM_STATS_NAME_SIZE,
.num_desc = ARRAY_SIZE(kvm_vcpu_stats_desc),
.id_offset = sizeof(struct kvm_stats_header),
.desc_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE,
.data_offset = sizeof(struct kvm_stats_header) + KVM_STATS_NAME_SIZE +
sizeof(kvm_vcpu_stats_desc),
};
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
#define KVM_RISCV_BASE_ISA_MASK GENMASK(25, 0)
RISC-V: KVM: Restrict the extensions that can be disabled Currently, the config isa register allows us to disable all allowed single letter ISA extensions. It shouldn't be the case as vmm shouldn't be able to disable base extensions (imac). These extensions should always be enabled as long as they are enabled in the host ISA. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org> Fixes: 92ad82002c39 ("RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls")
2022-04-19 18:32:58 -07:00
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
/* Mapping between KVM ISA Extension ID & Host ISA extension ID */
static const unsigned long kvm_isa_ext_arr[] = {
RISCV_ISA_EXT_a,
RISCV_ISA_EXT_c,
RISCV_ISA_EXT_d,
RISCV_ISA_EXT_f,
RISCV_ISA_EXT_h,
RISCV_ISA_EXT_i,
RISCV_ISA_EXT_m,
RISC-V: KVM: Add support for Svpbmt inside Guest/VM The Guest/VM can use Svpbmt in VS-stage page tables when allowed by the Hypervisor using the henvcfg.PBMTE bit. We add Svpbmt support for the KVM Guest/VM which can be enabled/disabled by the KVM user-space (QEMU/KVMTOOL) using the ISA extension ONE_REG interface. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:15:18 +05:30
RISCV_ISA_EXT_SVPBMT,
RISC-V: KVM: Support sstc extension Sstc extension allows the guest to program the vstimecmp CSR directly instead of making an SBI call to the hypervisor to program the next event. The timer interrupt is also directly injected to the guest by the hardware in this case. To maintain backward compatibility, the hypervisors also update the vstimecmp in an SBI set_time call if the hardware supports it. Thus, the older kernels in guest also take advantage of the sstc extension. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atishp@rivosinc.com> Acked-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/all/CAAhSdy2mb6wyqy0NAn9BcTWKMYEc0Z4zU3s3j7oNqBz6eDQ9sg@mail.gmail.com/ Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-07-22 09:50:47 -07:00
RISCV_ISA_EXT_SSTC,
RISC-V: KVM: Allow Guest use Svinval extension We should advertise Svinval ISA extension to KVM user-space whenever host supports it. This will allow KVM user-space (i.e. QEMU or KVMTOOL) to pass on this information to Guest via ISA string. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-10-02 10:18:42 +05:30
RISCV_ISA_EXT_SVINVAL,
RISC-V: KVM: Allow Guest use Zihintpause extension We should advertise Zihintpause ISA extension to KVM user-space whenever host supports it. This will allow KVM user-space (i.e. QEMU or KVMTOOL) to pass on this information to Guest via ISA string. Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-10-02 10:18:48 +05:30
RISCV_ISA_EXT_ZIHINTPAUSE,
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
};
static unsigned long kvm_riscv_vcpu_base2isa_ext(unsigned long base_ext)
{
unsigned long i;
for (i = 0; i < KVM_RISCV_ISA_EXT_MAX; i++) {
if (kvm_isa_ext_arr[i] == base_ext)
return i;
}
return KVM_RISCV_ISA_EXT_MAX;
}
static bool kvm_riscv_vcpu_isa_enable_allowed(unsigned long ext)
{
switch (ext) {
case KVM_RISCV_ISA_EXT_H:
return false;
default:
break;
}
return true;
}
static bool kvm_riscv_vcpu_isa_disable_allowed(unsigned long ext)
{
switch (ext) {
case KVM_RISCV_ISA_EXT_A:
case KVM_RISCV_ISA_EXT_C:
case KVM_RISCV_ISA_EXT_I:
case KVM_RISCV_ISA_EXT_M:
RISC-V: KVM: Support sstc extension Sstc extension allows the guest to program the vstimecmp CSR directly instead of making an SBI call to the hypervisor to program the next event. The timer interrupt is also directly injected to the guest by the hardware in this case. To maintain backward compatibility, the hypervisors also update the vstimecmp in an SBI set_time call if the hardware supports it. Thus, the older kernels in guest also take advantage of the sstc extension. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atishp@rivosinc.com> Acked-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/all/CAAhSdy2mb6wyqy0NAn9BcTWKMYEc0Z4zU3s3j7oNqBz6eDQ9sg@mail.gmail.com/ Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-07-22 09:50:47 -07:00
case KVM_RISCV_ISA_EXT_SSTC:
RISC-V: KVM: Allow Guest use Svinval extension We should advertise Svinval ISA extension to KVM user-space whenever host supports it. This will allow KVM user-space (i.e. QEMU or KVMTOOL) to pass on this information to Guest via ISA string. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-10-02 10:18:42 +05:30
case KVM_RISCV_ISA_EXT_SVINVAL:
RISC-V: KVM: Allow Guest use Zihintpause extension We should advertise Zihintpause ISA extension to KVM user-space whenever host supports it. This will allow KVM user-space (i.e. QEMU or KVMTOOL) to pass on this information to Guest via ISA string. Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-10-02 10:18:48 +05:30
case KVM_RISCV_ISA_EXT_ZIHINTPAUSE:
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
return false;
default:
break;
}
RISC-V: KVM: Restrict the extensions that can be disabled Currently, the config isa register allows us to disable all allowed single letter ISA extensions. It shouldn't be the case as vmm shouldn't be able to disable base extensions (imac). These extensions should always be enabled as long as they are enabled in the host ISA. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org> Fixes: 92ad82002c39 ("RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls")
2022-04-19 18:32:58 -07:00
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
return true;
}
RISC-V: KVM: Implement VCPU create, init and destroy functions This patch implements VCPU create, init and destroy functions required by generic KVM module. We don't have much dynamic resources in struct kvm_vcpu_arch so these functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:02 +05:30
static void kvm_riscv_reset_vcpu(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr;
struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
struct kvm_cpu_context *reset_cntx = &vcpu->arch.guest_reset_context;
RISC-V: KVM: Add SBI HSM extension in KVM SBI HSM extension allows OS to start/stop harts any time. It also allows ordered booting of harts instead of random booting. Implement SBI HSM exntesion and designate the vcpu 0 as the boot vcpu id. All other non-zero non-booting vcpus should be brought up by the OS implementing HSM extension. If the guest OS doesn't implement HSM extension, only single vcpu will be available to OS. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com>
2021-11-18 00:39:12 -08:00
bool loaded;
/**
* The preemption should be disabled here because it races with
* kvm_sched_out/kvm_sched_in(called from preempt notifiers) which
* also calls vcpu_load/put.
*/
get_cpu();
loaded = (vcpu->cpu != -1);
if (loaded)
kvm_arch_vcpu_put(vcpu);
RISC-V: KVM: Implement VCPU create, init and destroy functions This patch implements VCPU create, init and destroy functions required by generic KVM module. We don't have much dynamic resources in struct kvm_vcpu_arch so these functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:02 +05:30
RISC-V: KVM: Cleanup stale TLB entries when host CPU changes On RISC-V platforms with hardware VMID support, we share same VMID for all VCPUs of a particular Guest/VM. This means we might have stale G-stage TLB entries on the current Host CPU due to some other VCPU of the same Guest which ran previously on the current Host CPU. To cleanup stale TLB entries, we simply flush all G-stage TLB entries by VMID whenever underlying Host CPU changes for a VCPU. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 10:44:11 +05:30
vcpu->arch.last_exit_cpu = -1;
RISC-V: KVM: Implement VCPU create, init and destroy functions This patch implements VCPU create, init and destroy functions required by generic KVM module. We don't have much dynamic resources in struct kvm_vcpu_arch so these functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:02 +05:30
memcpy(csr, reset_csr, sizeof(*csr));
memcpy(cntx, reset_cntx, sizeof(*cntx));
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
RISC-V: KVM: FP lazy save/restore This patch adds floating point (F and D extension) context save/restore for guest VCPUs. The FP context is saved and restored lazily only when kernel enter/exits the in-kernel run loop and not during the KVM world switch. This way FP save/restore has minimal impact on KVM performance. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:12 +05:30
kvm_riscv_vcpu_fp_reset(vcpu);
RISC-V: KVM: Add timer functionality The RISC-V hypervisor specification doesn't have any virtual timer feature. Due to this, the guest VCPU timer will be programmed via SBI calls. The host will use a separate hrtimer event for each guest VCPU to provide timer functionality. We inject a virtual timer interrupt to the guest VCPU whenever the guest VCPU hrtimer event expires. This patch adds guest VCPU timer implementation along with ONE_REG interface to access VCPU timer state from user space. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:11 +05:30
kvm_riscv_vcpu_timer_reset(vcpu);
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
WRITE_ONCE(vcpu->arch.irqs_pending, 0);
WRITE_ONCE(vcpu->arch.irqs_pending_mask, 0);
RISC-V: KVM: Add SBI HSM extension in KVM SBI HSM extension allows OS to start/stop harts any time. It also allows ordered booting of harts instead of random booting. Implement SBI HSM exntesion and designate the vcpu 0 as the boot vcpu id. All other non-zero non-booting vcpus should be brought up by the OS implementing HSM extension. If the guest OS doesn't implement HSM extension, only single vcpu will be available to OS. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com>
2021-11-18 00:39:12 -08:00
RISC-V: KVM: Add remote HFENCE functions based on VCPU requests The generic KVM has support for VCPU requests which can be used to do arch-specific work in the run-loop. We introduce remote HFENCE functions which will internally use VCPU requests instead of host SBI calls. Advantages of doing remote HFENCEs as VCPU requests are: 1) Multiple VCPUs of a Guest may be running on different Host CPUs so it is not always possible to determine the Host CPU mask for doing Host SBI call. For example, when VCPU X wants to do HFENCE on VCPU Y, it is possible that VCPU Y is blocked or in user-space (i.e. vcpu->cpu < 0). 2) To support nested virtualization, we will be having a separate shadow G-stage for each VCPU and a common host G-stage for the entire Guest/VM. The VCPU requests based remote HFENCEs helps us easily synchronize the common host G-stage and shadow G-stage of each VCPU without any additional IPI calls. This is also a preparatory patch for upcoming nested virtualization support where we will be having a shadow G-stage page table for each Guest VCPU. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 10:44:05 +05:30
vcpu->arch.hfence_head = 0;
vcpu->arch.hfence_tail = 0;
memset(vcpu->arch.hfence_queue, 0, sizeof(vcpu->arch.hfence_queue));
RISC-V: KVM: Add SBI HSM extension in KVM SBI HSM extension allows OS to start/stop harts any time. It also allows ordered booting of harts instead of random booting. Implement SBI HSM exntesion and designate the vcpu 0 as the boot vcpu id. All other non-zero non-booting vcpus should be brought up by the OS implementing HSM extension. If the guest OS doesn't implement HSM extension, only single vcpu will be available to OS. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com>
2021-11-18 00:39:12 -08:00
/* Reset the guest CSRs for hotplug usecase */
if (loaded)
kvm_arch_vcpu_load(vcpu, smp_processor_id());
put_cpu();
RISC-V: KVM: Implement VCPU create, init and destroy functions This patch implements VCPU create, init and destroy functions required by generic KVM module. We don't have much dynamic resources in struct kvm_vcpu_arch so these functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:02 +05:30
}
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
{
return 0;
}
int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
{
RISC-V: KVM: Implement VCPU create, init and destroy functions This patch implements VCPU create, init and destroy functions required by generic KVM module. We don't have much dynamic resources in struct kvm_vcpu_arch so these functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:02 +05:30
struct kvm_cpu_context *cntx;
RISC-V: KVM: make CY, TM, and IR counters accessible in VU mode Those applications that run in VU mode and access the time CSR cause a virtual instruction trap as Guest kernel currently does not initialize the scounteren CSR. To fix this, we should make CY, TM, and IR counters accessibile by default in VU mode (similar to OpenSBI). Fixes: a33c72faf2d73 ("RISC-V: KVM: Implement VCPU create, init and destroy functions") Cc: stable@vger.kernel.org Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-01-31 16:33:07 +05:30
struct kvm_vcpu_csr *reset_csr = &vcpu->arch.guest_reset_csr;
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
unsigned long host_isa, i;
RISC-V: KVM: Implement VCPU create, init and destroy functions This patch implements VCPU create, init and destroy functions required by generic KVM module. We don't have much dynamic resources in struct kvm_vcpu_arch so these functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:02 +05:30
/* Mark this VCPU never ran */
vcpu->arch.ran_atleast_once = false;
KVM: RISC-V: Use common KVM implementation of MMU memory caches Use common KVM's implementation of the MMU memory caches, which for all intents and purposes is semantically identical to RISC-V's version, the only difference being that the common implementation will fall back to an atomic allocation if there's a KVM bug that triggers a cache underflow. RISC-V appears to have based its MMU code on arm64 before the conversion to the common caches in commit c1a33aebe91d ("KVM: arm64: Use common KVM implementation of MMU memory caches"), despite having also copy-pasted the definition of KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE in kvm_types.h. Opportunistically drop the superfluous wrapper kvm_riscv_stage2_flush_cache(), whose name is very, very confusing as "cache flush" in the context of MMU code almost always refers to flushing hardware caches, not freeing unused software objects. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Anup Patel <anup.patel@wdc.com>
2021-11-04 16:41:07 +00:00
vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO;
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
bitmap_zero(vcpu->arch.isa, RISCV_ISA_EXT_MAX);
RISC-V: KVM: Implement VCPU create, init and destroy functions This patch implements VCPU create, init and destroy functions required by generic KVM module. We don't have much dynamic resources in struct kvm_vcpu_arch so these functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:02 +05:30
/* Setup ISA features available to VCPU */
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
for (i = 0; i < ARRAY_SIZE(kvm_isa_ext_arr); i++) {
host_isa = kvm_isa_ext_arr[i];
if (__riscv_isa_extension_available(NULL, host_isa) &&
kvm_riscv_vcpu_isa_enable_allowed(i))
set_bit(host_isa, vcpu->arch.isa);
}
RISC-V: KVM: Implement VCPU create, init and destroy functions This patch implements VCPU create, init and destroy functions required by generic KVM module. We don't have much dynamic resources in struct kvm_vcpu_arch so these functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:02 +05:30
RISC-V: KVM: Add remote HFENCE functions based on VCPU requests The generic KVM has support for VCPU requests which can be used to do arch-specific work in the run-loop. We introduce remote HFENCE functions which will internally use VCPU requests instead of host SBI calls. Advantages of doing remote HFENCEs as VCPU requests are: 1) Multiple VCPUs of a Guest may be running on different Host CPUs so it is not always possible to determine the Host CPU mask for doing Host SBI call. For example, when VCPU X wants to do HFENCE on VCPU Y, it is possible that VCPU Y is blocked or in user-space (i.e. vcpu->cpu < 0). 2) To support nested virtualization, we will be having a separate shadow G-stage for each VCPU and a common host G-stage for the entire Guest/VM. The VCPU requests based remote HFENCEs helps us easily synchronize the common host G-stage and shadow G-stage of each VCPU without any additional IPI calls. This is also a preparatory patch for upcoming nested virtualization support where we will be having a shadow G-stage page table for each Guest VCPU. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 10:44:05 +05:30
/* Setup VCPU hfence queue */
spin_lock_init(&vcpu->arch.hfence_lock);
RISC-V: KVM: Implement VCPU create, init and destroy functions This patch implements VCPU create, init and destroy functions required by generic KVM module. We don't have much dynamic resources in struct kvm_vcpu_arch so these functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:02 +05:30
/* Setup reset state of shadow SSTATUS and HSTATUS CSRs */
cntx = &vcpu->arch.guest_reset_context;
cntx->sstatus = SR_SPP | SR_SPIE;
cntx->hstatus = 0;
cntx->hstatus |= HSTATUS_VTW;
cntx->hstatus |= HSTATUS_SPVP;
cntx->hstatus |= HSTATUS_SPV;
RISC-V: KVM: make CY, TM, and IR counters accessible in VU mode Those applications that run in VU mode and access the time CSR cause a virtual instruction trap as Guest kernel currently does not initialize the scounteren CSR. To fix this, we should make CY, TM, and IR counters accessibile by default in VU mode (similar to OpenSBI). Fixes: a33c72faf2d73 ("RISC-V: KVM: Implement VCPU create, init and destroy functions") Cc: stable@vger.kernel.org Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-01-31 16:33:07 +05:30
/* By default, make CY, TM, and IR counters accessible in VU mode */
reset_csr->scounteren = 0x7;
RISC-V: KVM: Add timer functionality The RISC-V hypervisor specification doesn't have any virtual timer feature. Due to this, the guest VCPU timer will be programmed via SBI calls. The host will use a separate hrtimer event for each guest VCPU to provide timer functionality. We inject a virtual timer interrupt to the guest VCPU whenever the guest VCPU hrtimer event expires. This patch adds guest VCPU timer implementation along with ONE_REG interface to access VCPU timer state from user space. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:11 +05:30
/* Setup VCPU timer */
kvm_riscv_vcpu_timer_init(vcpu);
RISC-V: KVM: Implement VCPU create, init and destroy functions This patch implements VCPU create, init and destroy functions required by generic KVM module. We don't have much dynamic resources in struct kvm_vcpu_arch so these functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:02 +05:30
/* Reset VCPU */
kvm_riscv_reset_vcpu(vcpu);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
return 0;
}
void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
{
RISC-V: KVM: Add SBI HSM extension in KVM SBI HSM extension allows OS to start/stop harts any time. It also allows ordered booting of harts instead of random booting. Implement SBI HSM exntesion and designate the vcpu 0 as the boot vcpu id. All other non-zero non-booting vcpus should be brought up by the OS implementing HSM extension. If the guest OS doesn't implement HSM extension, only single vcpu will be available to OS. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com>
2021-11-18 00:39:12 -08:00
/**
* vcpu with id 0 is the designated boot cpu.
* Keep all vcpus with non-zero id in power-off state so that
* they can be brought up using SBI HSM extension.
*/
if (vcpu->vcpu_idx != 0)
kvm_riscv_vcpu_power_off(vcpu);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
}
void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
{
RISC-V: KVM: Add timer functionality The RISC-V hypervisor specification doesn't have any virtual timer feature. Due to this, the guest VCPU timer will be programmed via SBI calls. The host will use a separate hrtimer event for each guest VCPU to provide timer functionality. We inject a virtual timer interrupt to the guest VCPU whenever the guest VCPU hrtimer event expires. This patch adds guest VCPU timer implementation along with ONE_REG interface to access VCPU timer state from user space. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:11 +05:30
/* Cleanup VCPU timer */
kvm_riscv_vcpu_timer_deinit(vcpu);
RISC-V: KVM: Use G-stage name for hypervisor page table The two-stage address translation defined by the RISC-V privileged specification defines: VS-stage (guest virtual address to guest physical address) programmed by the Guest OS and G-stage (guest physical addree to host physical address) programmed by the hypervisor. To align with above terminology, we replace "stage2" with "gstage" and "Stage2" with "G-stage" name everywhere in KVM RISC-V sources. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 10:43:30 +05:30
/* Free unused pages pre-allocated for G-stage page table mappings */
KVM: RISC-V: Use common KVM implementation of MMU memory caches Use common KVM's implementation of the MMU memory caches, which for all intents and purposes is semantically identical to RISC-V's version, the only difference being that the common implementation will fall back to an atomic allocation if there's a KVM bug that triggers a cache underflow. RISC-V appears to have based its MMU code on arm64 before the conversion to the common caches in commit c1a33aebe91d ("KVM: arm64: Use common KVM implementation of MMU memory caches"), despite having also copy-pasted the definition of KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE in kvm_types.h. Opportunistically drop the superfluous wrapper kvm_riscv_stage2_flush_cache(), whose name is very, very confusing as "cache flush" in the context of MMU code almost always refers to flushing hardware caches, not freeing unused software objects. No functional change intended. Signed-off-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Anup Patel <anup.patel@wdc.com>
2021-11-04 16:41:07 +00:00
kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
}
int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
{
RISC-V: KVM: Support sstc extension Sstc extension allows the guest to program the vstimecmp CSR directly instead of making an SBI call to the hypervisor to program the next event. The timer interrupt is also directly injected to the guest by the hardware in this case. To maintain backward compatibility, the hypervisors also update the vstimecmp in an SBI set_time call if the hardware supports it. Thus, the older kernels in guest also take advantage of the sstc extension. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atishp@rivosinc.com> Acked-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/all/CAAhSdy2mb6wyqy0NAn9BcTWKMYEc0Z4zU3s3j7oNqBz6eDQ9sg@mail.gmail.com/ Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-07-22 09:50:47 -07:00
return kvm_riscv_vcpu_timer_pending(vcpu);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
}
void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
{
}
void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
{
}
int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
{
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
return (kvm_riscv_vcpu_has_interrupts(vcpu, -1UL) &&
!vcpu->arch.power_off && !vcpu->arch.pause);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
}
int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
{
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
}
bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
{
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
return (vcpu->arch.guest_context.sstatus & SR_SPP) ? true : false;
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
}
vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
{
return VM_FAULT_SIGBUS;
}
RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access VCPU config and registers from user-space. We have three types of VCPU registers: 1. CONFIG - these are VCPU config and capabilities 2. CORE - these are VCPU general purpose registers 3. CSR - these are VCPU control and status registers The CONFIG register available to user-space is ISA. The ISA register is a read and write register where user-space can only write the desired VCPU ISA capabilities before running the VCPU. The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7, T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except PC and MODE. The PC register represents program counter whereas the MODE register represent VCPU privilege mode (i.e. S/U-mode). The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC, SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers. In future, more VCPU register types will be added (such as FP) for the KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:04 +05:30
static int kvm_riscv_vcpu_get_reg_config(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_CONFIG);
unsigned long reg_val;
if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
return -EINVAL;
switch (reg_num) {
case KVM_REG_RISCV_CONFIG_REG(isa):
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
reg_val = vcpu->arch.isa[0] & KVM_RISCV_BASE_ISA_MASK;
RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access VCPU config and registers from user-space. We have three types of VCPU registers: 1. CONFIG - these are VCPU config and capabilities 2. CORE - these are VCPU general purpose registers 3. CSR - these are VCPU control and status registers The CONFIG register available to user-space is ISA. The ISA register is a read and write register where user-space can only write the desired VCPU ISA capabilities before running the VCPU. The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7, T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except PC and MODE. The PC register represents program counter whereas the MODE register represent VCPU privilege mode (i.e. S/U-mode). The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC, SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers. In future, more VCPU register types will be added (such as FP) for the KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:04 +05:30
break;
default:
return -EINVAL;
RISC-V: KVM: remove unneeded semicolon Elimate the following coccinelle check warning: ./arch/riscv/kvm/vcpu_sbi.c:169:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_exit.c:397:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_exit.c:687:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_exit.c:645:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu.c:247:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu.c:284:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_timer.c:123:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_timer.c:170:2-3: Unneeded semicolon Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: ran jianping <ran.jianping@zte.com.cn> Signed-off-by: Anup Patel <anup.patel@wdc.com>
2021-10-21 11:57:06 +00:00
}
RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access VCPU config and registers from user-space. We have three types of VCPU registers: 1. CONFIG - these are VCPU config and capabilities 2. CORE - these are VCPU general purpose registers 3. CSR - these are VCPU control and status registers The CONFIG register available to user-space is ISA. The ISA register is a read and write register where user-space can only write the desired VCPU ISA capabilities before running the VCPU. The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7, T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except PC and MODE. The PC register represents program counter whereas the MODE register represent VCPU privilege mode (i.e. S/U-mode). The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC, SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers. In future, more VCPU register types will be added (such as FP) for the KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:04 +05:30
if (copy_to_user(uaddr, &reg_val, KVM_REG_SIZE(reg->id)))
return -EFAULT;
return 0;
}
static int kvm_riscv_vcpu_set_reg_config(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_CONFIG);
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
unsigned long i, isa_ext, reg_val;
RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access VCPU config and registers from user-space. We have three types of VCPU registers: 1. CONFIG - these are VCPU config and capabilities 2. CORE - these are VCPU general purpose registers 3. CSR - these are VCPU control and status registers The CONFIG register available to user-space is ISA. The ISA register is a read and write register where user-space can only write the desired VCPU ISA capabilities before running the VCPU. The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7, T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except PC and MODE. The PC register represents program counter whereas the MODE register represent VCPU privilege mode (i.e. S/U-mode). The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC, SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers. In future, more VCPU register types will be added (such as FP) for the KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:04 +05:30
if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
return -EINVAL;
if (copy_from_user(&reg_val, uaddr, KVM_REG_SIZE(reg->id)))
return -EFAULT;
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
/* This ONE REG interface is only defined for single letter extensions */
if (fls(reg_val) >= RISCV_ISA_EXT_BASE)
return -EINVAL;
RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access VCPU config and registers from user-space. We have three types of VCPU registers: 1. CONFIG - these are VCPU config and capabilities 2. CORE - these are VCPU general purpose registers 3. CSR - these are VCPU control and status registers The CONFIG register available to user-space is ISA. The ISA register is a read and write register where user-space can only write the desired VCPU ISA capabilities before running the VCPU. The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7, T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except PC and MODE. The PC register represents program counter whereas the MODE register represent VCPU privilege mode (i.e. S/U-mode). The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC, SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers. In future, more VCPU register types will be added (such as FP) for the KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:04 +05:30
switch (reg_num) {
case KVM_REG_RISCV_CONFIG_REG(isa):
if (!vcpu->arch.ran_atleast_once) {
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
/* Ignore the enable/disable request for certain extensions */
for (i = 0; i < RISCV_ISA_EXT_BASE; i++) {
isa_ext = kvm_riscv_vcpu_base2isa_ext(i);
if (isa_ext >= KVM_RISCV_ISA_EXT_MAX) {
reg_val &= ~BIT(i);
continue;
}
if (!kvm_riscv_vcpu_isa_enable_allowed(isa_ext))
if (reg_val & BIT(i))
reg_val &= ~BIT(i);
if (!kvm_riscv_vcpu_isa_disable_allowed(isa_ext))
if (!(reg_val & BIT(i)))
reg_val |= BIT(i);
}
reg_val &= riscv_isa_extension_base(NULL);
/* Do not modify anything beyond single letter extensions */
reg_val = (vcpu->arch.isa[0] & ~KVM_RISCV_BASE_ISA_MASK) |
(reg_val & KVM_RISCV_BASE_ISA_MASK);
vcpu->arch.isa[0] = reg_val;
RISC-V: KVM: FP lazy save/restore This patch adds floating point (F and D extension) context save/restore for guest VCPUs. The FP context is saved and restored lazily only when kernel enter/exits the in-kernel run loop and not during the KVM world switch. This way FP save/restore has minimal impact on KVM performance. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:12 +05:30
kvm_riscv_vcpu_fp_reset(vcpu);
RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access VCPU config and registers from user-space. We have three types of VCPU registers: 1. CONFIG - these are VCPU config and capabilities 2. CORE - these are VCPU general purpose registers 3. CSR - these are VCPU control and status registers The CONFIG register available to user-space is ISA. The ISA register is a read and write register where user-space can only write the desired VCPU ISA capabilities before running the VCPU. The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7, T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except PC and MODE. The PC register represents program counter whereas the MODE register represent VCPU privilege mode (i.e. S/U-mode). The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC, SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers. In future, more VCPU register types will be added (such as FP) for the KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:04 +05:30
} else {
return -EOPNOTSUPP;
}
break;
default:
return -EINVAL;
RISC-V: KVM: remove unneeded semicolon Elimate the following coccinelle check warning: ./arch/riscv/kvm/vcpu_sbi.c:169:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_exit.c:397:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_exit.c:687:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_exit.c:645:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu.c:247:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu.c:284:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_timer.c:123:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_timer.c:170:2-3: Unneeded semicolon Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: ran jianping <ran.jianping@zte.com.cn> Signed-off-by: Anup Patel <anup.patel@wdc.com>
2021-10-21 11:57:06 +00:00
}
RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access VCPU config and registers from user-space. We have three types of VCPU registers: 1. CONFIG - these are VCPU config and capabilities 2. CORE - these are VCPU general purpose registers 3. CSR - these are VCPU control and status registers The CONFIG register available to user-space is ISA. The ISA register is a read and write register where user-space can only write the desired VCPU ISA capabilities before running the VCPU. The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7, T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except PC and MODE. The PC register represents program counter whereas the MODE register represent VCPU privilege mode (i.e. S/U-mode). The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC, SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers. In future, more VCPU register types will be added (such as FP) for the KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:04 +05:30
return 0;
}
static int kvm_riscv_vcpu_get_reg_core(struct kvm_vcpu *vcpu,
const struct kvm_one_reg *reg)
{
struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
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_CORE);
unsigned long reg_val;
if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
return -EINVAL;
if (reg_num >= sizeof(struct kvm_riscv_core) / sizeof(unsigned long))
return -EINVAL;
if (reg_num == KVM_REG_RISCV_CORE_REG(regs.pc))
reg_val = cntx->sepc;
else if (KVM_REG_RISCV_CORE_REG(regs.pc) < reg_num &&
reg_num <= KVM_REG_RISCV_CORE_REG(regs.t6))
reg_val = ((unsigned long *)cntx)[reg_num];
else if (reg_num == KVM_REG_RISCV_CORE_REG(mode))
reg_val = (cntx->sstatus & SR_SPP) ?
KVM_RISCV_MODE_S : KVM_RISCV_MODE_U;
else
return -EINVAL;
if (copy_to_user(uaddr, &reg_val, KVM_REG_SIZE(reg->id)))
return -EFAULT;
return 0;
}
static int kvm_riscv_vcpu_set_reg_core(struct kvm_vcpu *vcpu,
const struct kvm_one_reg *reg)
{
struct kvm_cpu_context *cntx = &vcpu->arch.guest_context;
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_CORE);
unsigned long reg_val;
if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
return -EINVAL;
if (reg_num >= sizeof(struct kvm_riscv_core) / sizeof(unsigned long))
return -EINVAL;
if (copy_from_user(&reg_val, uaddr, KVM_REG_SIZE(reg->id)))
return -EFAULT;
if (reg_num == KVM_REG_RISCV_CORE_REG(regs.pc))
cntx->sepc = reg_val;
else if (KVM_REG_RISCV_CORE_REG(regs.pc) < reg_num &&
reg_num <= KVM_REG_RISCV_CORE_REG(regs.t6))
((unsigned long *)cntx)[reg_num] = reg_val;
else if (reg_num == KVM_REG_RISCV_CORE_REG(mode)) {
if (reg_val == KVM_RISCV_MODE_S)
cntx->sstatus |= SR_SPP;
else
cntx->sstatus &= ~SR_SPP;
} else
return -EINVAL;
return 0;
}
static int kvm_riscv_vcpu_get_reg_csr(struct kvm_vcpu *vcpu,
const struct kvm_one_reg *reg)
{
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
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_CSR);
unsigned long reg_val;
if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
return -EINVAL;
if (reg_num >= sizeof(struct kvm_riscv_csr) / sizeof(unsigned long))
return -EINVAL;
if (reg_num == KVM_REG_RISCV_CSR_REG(sip)) {
kvm_riscv_vcpu_flush_interrupts(vcpu);
reg_val = (csr->hvip >> VSIP_TO_HVIP_SHIFT) & VSIP_VALID_MASK;
} else
reg_val = ((unsigned long *)csr)[reg_num];
if (copy_to_user(uaddr, &reg_val, KVM_REG_SIZE(reg->id)))
return -EFAULT;
return 0;
}
static int kvm_riscv_vcpu_set_reg_csr(struct kvm_vcpu *vcpu,
const struct kvm_one_reg *reg)
{
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
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_CSR);
unsigned long reg_val;
if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
return -EINVAL;
if (reg_num >= sizeof(struct kvm_riscv_csr) / sizeof(unsigned long))
return -EINVAL;
if (copy_from_user(&reg_val, uaddr, KVM_REG_SIZE(reg->id)))
return -EFAULT;
if (reg_num == KVM_REG_RISCV_CSR_REG(sip)) {
reg_val &= VSIP_VALID_MASK;
reg_val <<= VSIP_TO_HVIP_SHIFT;
}
((unsigned long *)csr)[reg_num] = reg_val;
if (reg_num == KVM_REG_RISCV_CSR_REG(sip))
WRITE_ONCE(vcpu->arch.irqs_pending_mask, 0);
return 0;
}
RISC-V: KVM: Introduce ISA extension register Currently, there is no provision for vmm (qemu-kvm or kvmtool) to query about multiple-letter ISA extensions. The config register is only used for base single letter ISA extensions. A new ISA extension register is added that will allow the vmm to query about any ISA extension one at a time. It is enabled for both single letter or multi-letter ISA extensions. The ISA extension register is useful to if the vmm requires to retrieve/set single extension while the config register should be used if all the base ISA extension required to retrieve or set. For any multi-letter ISA extensions, the new register interface must be used. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 11:29:37 -07:00
static int kvm_riscv_vcpu_get_reg_isa_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_ISA_EXT);
unsigned long reg_val = 0;
unsigned long host_isa_ext;
if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
return -EINVAL;
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
if (reg_num >= KVM_RISCV_ISA_EXT_MAX ||
reg_num >= ARRAY_SIZE(kvm_isa_ext_arr))
RISC-V: KVM: Introduce ISA extension register Currently, there is no provision for vmm (qemu-kvm or kvmtool) to query about multiple-letter ISA extensions. The config register is only used for base single letter ISA extensions. A new ISA extension register is added that will allow the vmm to query about any ISA extension one at a time. It is enabled for both single letter or multi-letter ISA extensions. The ISA extension register is useful to if the vmm requires to retrieve/set single extension while the config register should be used if all the base ISA extension required to retrieve or set. For any multi-letter ISA extensions, the new register interface must be used. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 11:29:37 -07:00
return -EINVAL;
host_isa_ext = kvm_isa_ext_arr[reg_num];
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
if (__riscv_isa_extension_available(vcpu->arch.isa, host_isa_ext))
RISC-V: KVM: Introduce ISA extension register Currently, there is no provision for vmm (qemu-kvm or kvmtool) to query about multiple-letter ISA extensions. The config register is only used for base single letter ISA extensions. A new ISA extension register is added that will allow the vmm to query about any ISA extension one at a time. It is enabled for both single letter or multi-letter ISA extensions. The ISA extension register is useful to if the vmm requires to retrieve/set single extension while the config register should be used if all the base ISA extension required to retrieve or set. For any multi-letter ISA extensions, the new register interface must be used. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 11:29:37 -07:00
reg_val = 1; /* Mark the given extension as available */
if (copy_to_user(uaddr, &reg_val, KVM_REG_SIZE(reg->id)))
return -EFAULT;
return 0;
}
static int kvm_riscv_vcpu_set_reg_isa_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_ISA_EXT);
unsigned long reg_val;
unsigned long host_isa_ext;
if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long))
return -EINVAL;
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
if (reg_num >= KVM_RISCV_ISA_EXT_MAX ||
reg_num >= ARRAY_SIZE(kvm_isa_ext_arr))
RISC-V: KVM: Introduce ISA extension register Currently, there is no provision for vmm (qemu-kvm or kvmtool) to query about multiple-letter ISA extensions. The config register is only used for base single letter ISA extensions. A new ISA extension register is added that will allow the vmm to query about any ISA extension one at a time. It is enabled for both single letter or multi-letter ISA extensions. The ISA extension register is useful to if the vmm requires to retrieve/set single extension while the config register should be used if all the base ISA extension required to retrieve or set. For any multi-letter ISA extensions, the new register interface must be used. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 11:29:37 -07:00
return -EINVAL;
if (copy_from_user(&reg_val, uaddr, KVM_REG_SIZE(reg->id)))
return -EFAULT;
host_isa_ext = kvm_isa_ext_arr[reg_num];
if (!__riscv_isa_extension_available(NULL, host_isa_ext))
return -EOPNOTSUPP;
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
if (!vcpu->arch.ran_atleast_once) {
RISC-V: KVM: Introduce ISA extension register Currently, there is no provision for vmm (qemu-kvm or kvmtool) to query about multiple-letter ISA extensions. The config register is only used for base single letter ISA extensions. A new ISA extension register is added that will allow the vmm to query about any ISA extension one at a time. It is enabled for both single letter or multi-letter ISA extensions. The ISA extension register is useful to if the vmm requires to retrieve/set single extension while the config register should be used if all the base ISA extension required to retrieve or set. For any multi-letter ISA extensions, the new register interface must be used. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 11:29:37 -07:00
/*
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
* All multi-letter extension and a few single letter
* extension can be disabled
RISC-V: KVM: Introduce ISA extension register Currently, there is no provision for vmm (qemu-kvm or kvmtool) to query about multiple-letter ISA extensions. The config register is only used for base single letter ISA extensions. A new ISA extension register is added that will allow the vmm to query about any ISA extension one at a time. It is enabled for both single letter or multi-letter ISA extensions. The ISA extension register is useful to if the vmm requires to retrieve/set single extension while the config register should be used if all the base ISA extension required to retrieve or set. For any multi-letter ISA extensions, the new register interface must be used. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 11:29:37 -07:00
*/
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
if (reg_val == 1 &&
kvm_riscv_vcpu_isa_enable_allowed(reg_num))
set_bit(host_isa_ext, vcpu->arch.isa);
else if (!reg_val &&
kvm_riscv_vcpu_isa_disable_allowed(reg_num))
clear_bit(host_isa_ext, vcpu->arch.isa);
RISC-V: KVM: Introduce ISA extension register Currently, there is no provision for vmm (qemu-kvm or kvmtool) to query about multiple-letter ISA extensions. The config register is only used for base single letter ISA extensions. A new ISA extension register is added that will allow the vmm to query about any ISA extension one at a time. It is enabled for both single letter or multi-letter ISA extensions. The ISA extension register is useful to if the vmm requires to retrieve/set single extension while the config register should be used if all the base ISA extension required to retrieve or set. For any multi-letter ISA extensions, the new register interface must be used. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 11:29:37 -07:00
else
RISC-V: KVM: Improve ISA extension by using a bitmap Currently, the every vcpu only stores the ISA extensions in a unsigned long which is not scalable as number of extensions will continue to grow. Using a bitmap allows the ISA extension to support any number of extensions. The CONFIG one reg interface implementation is modified to support the bitmap as well. But it is meant only for base extensions. Thus, the first element of the bitmap array is sufficient for that interface. In the future, all the new multi-letter extensions must use the ISA_EXT one reg interface that allows enabling/disabling any extension now. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:11 +05:30
return -EINVAL;
RISC-V: KVM: Introduce ISA extension register Currently, there is no provision for vmm (qemu-kvm or kvmtool) to query about multiple-letter ISA extensions. The config register is only used for base single letter ISA extensions. A new ISA extension register is added that will allow the vmm to query about any ISA extension one at a time. It is enabled for both single letter or multi-letter ISA extensions. The ISA extension register is useful to if the vmm requires to retrieve/set single extension while the config register should be used if all the base ISA extension required to retrieve or set. For any multi-letter ISA extensions, the new register interface must be used. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 11:29:37 -07:00
kvm_riscv_vcpu_fp_reset(vcpu);
} else {
return -EOPNOTSUPP;
}
return 0;
}
RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access VCPU config and registers from user-space. We have three types of VCPU registers: 1. CONFIG - these are VCPU config and capabilities 2. CORE - these are VCPU general purpose registers 3. CSR - these are VCPU control and status registers The CONFIG register available to user-space is ISA. The ISA register is a read and write register where user-space can only write the desired VCPU ISA capabilities before running the VCPU. The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7, T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except PC and MODE. The PC register represents program counter whereas the MODE register represent VCPU privilege mode (i.e. S/U-mode). The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC, SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers. In future, more VCPU register types will be added (such as FP) for the KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:04 +05:30
static int kvm_riscv_vcpu_set_reg(struct kvm_vcpu *vcpu,
const struct kvm_one_reg *reg)
{
if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CONFIG)
return kvm_riscv_vcpu_set_reg_config(vcpu, reg);
else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CORE)
return kvm_riscv_vcpu_set_reg_core(vcpu, reg);
else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CSR)
return kvm_riscv_vcpu_set_reg_csr(vcpu, reg);
RISC-V: KVM: Add timer functionality The RISC-V hypervisor specification doesn't have any virtual timer feature. Due to this, the guest VCPU timer will be programmed via SBI calls. The host will use a separate hrtimer event for each guest VCPU to provide timer functionality. We inject a virtual timer interrupt to the guest VCPU whenever the guest VCPU hrtimer event expires. This patch adds guest VCPU timer implementation along with ONE_REG interface to access VCPU timer state from user space. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:11 +05:30
else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_TIMER)
return kvm_riscv_vcpu_set_reg_timer(vcpu, reg);
RISC-V: KVM: Implement ONE REG interface for FP registers Add a KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctl interface for floating point registers such as F0-F31 and FCSR. This support is added for both 'F' and 'D' extensions. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:13 +05:30
else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_FP_F)
return kvm_riscv_vcpu_set_reg_fp(vcpu, reg,
KVM_REG_RISCV_FP_F);
else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_FP_D)
return kvm_riscv_vcpu_set_reg_fp(vcpu, reg,
KVM_REG_RISCV_FP_D);
RISC-V: KVM: Introduce ISA extension register Currently, there is no provision for vmm (qemu-kvm or kvmtool) to query about multiple-letter ISA extensions. The config register is only used for base single letter ISA extensions. A new ISA extension register is added that will allow the vmm to query about any ISA extension one at a time. It is enabled for both single letter or multi-letter ISA extensions. The ISA extension register is useful to if the vmm requires to retrieve/set single extension while the config register should be used if all the base ISA extension required to retrieve or set. For any multi-letter ISA extensions, the new register interface must be used. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 11:29:37 -07:00
else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_ISA_EXT)
return kvm_riscv_vcpu_set_reg_isa_ext(vcpu, reg);
RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access VCPU config and registers from user-space. We have three types of VCPU registers: 1. CONFIG - these are VCPU config and capabilities 2. CORE - these are VCPU general purpose registers 3. CSR - these are VCPU control and status registers The CONFIG register available to user-space is ISA. The ISA register is a read and write register where user-space can only write the desired VCPU ISA capabilities before running the VCPU. The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7, T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except PC and MODE. The PC register represents program counter whereas the MODE register represent VCPU privilege mode (i.e. S/U-mode). The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC, SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers. In future, more VCPU register types will be added (such as FP) for the KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:04 +05:30
return -EINVAL;
}
static int kvm_riscv_vcpu_get_reg(struct kvm_vcpu *vcpu,
const struct kvm_one_reg *reg)
{
if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CONFIG)
return kvm_riscv_vcpu_get_reg_config(vcpu, reg);
else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CORE)
return kvm_riscv_vcpu_get_reg_core(vcpu, reg);
else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_CSR)
return kvm_riscv_vcpu_get_reg_csr(vcpu, reg);
RISC-V: KVM: Add timer functionality The RISC-V hypervisor specification doesn't have any virtual timer feature. Due to this, the guest VCPU timer will be programmed via SBI calls. The host will use a separate hrtimer event for each guest VCPU to provide timer functionality. We inject a virtual timer interrupt to the guest VCPU whenever the guest VCPU hrtimer event expires. This patch adds guest VCPU timer implementation along with ONE_REG interface to access VCPU timer state from user space. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:11 +05:30
else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_TIMER)
return kvm_riscv_vcpu_get_reg_timer(vcpu, reg);
RISC-V: KVM: Implement ONE REG interface for FP registers Add a KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctl interface for floating point registers such as F0-F31 and FCSR. This support is added for both 'F' and 'D' extensions. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:13 +05:30
else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_FP_F)
return kvm_riscv_vcpu_get_reg_fp(vcpu, reg,
KVM_REG_RISCV_FP_F);
else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_FP_D)
return kvm_riscv_vcpu_get_reg_fp(vcpu, reg,
KVM_REG_RISCV_FP_D);
RISC-V: KVM: Introduce ISA extension register Currently, there is no provision for vmm (qemu-kvm or kvmtool) to query about multiple-letter ISA extensions. The config register is only used for base single letter ISA extensions. A new ISA extension register is added that will allow the vmm to query about any ISA extension one at a time. It is enabled for both single letter or multi-letter ISA extensions. The ISA extension register is useful to if the vmm requires to retrieve/set single extension while the config register should be used if all the base ISA extension required to retrieve or set. For any multi-letter ISA extensions, the new register interface must be used. Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 11:29:37 -07:00
else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_ISA_EXT)
return kvm_riscv_vcpu_get_reg_isa_ext(vcpu, reg);
RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access VCPU config and registers from user-space. We have three types of VCPU registers: 1. CONFIG - these are VCPU config and capabilities 2. CORE - these are VCPU general purpose registers 3. CSR - these are VCPU control and status registers The CONFIG register available to user-space is ISA. The ISA register is a read and write register where user-space can only write the desired VCPU ISA capabilities before running the VCPU. The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7, T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except PC and MODE. The PC register represents program counter whereas the MODE register represent VCPU privilege mode (i.e. S/U-mode). The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC, SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers. In future, more VCPU register types will be added (such as FP) for the KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:04 +05:30
return -EINVAL;
}
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
long kvm_arch_vcpu_async_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
struct kvm_vcpu *vcpu = filp->private_data;
void __user *argp = (void __user *)arg;
if (ioctl == KVM_INTERRUPT) {
struct kvm_interrupt irq;
if (copy_from_user(&irq, argp, sizeof(irq)))
return -EFAULT;
if (irq.irq == KVM_INTERRUPT_SET)
return kvm_riscv_vcpu_set_interrupt(vcpu, IRQ_VS_EXT);
else
return kvm_riscv_vcpu_unset_interrupt(vcpu, IRQ_VS_EXT);
}
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
return -ENOIOCTLCMD;
}
long kvm_arch_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
RISC-V: KVM: Implement KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls For KVM RISC-V, we use KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls to access VCPU config and registers from user-space. We have three types of VCPU registers: 1. CONFIG - these are VCPU config and capabilities 2. CORE - these are VCPU general purpose registers 3. CSR - these are VCPU control and status registers The CONFIG register available to user-space is ISA. The ISA register is a read and write register where user-space can only write the desired VCPU ISA capabilities before running the VCPU. The CORE registers available to user-space are PC, RA, SP, GP, TP, A0-A7, T0-T6, S0-S11 and MODE. Most of these are RISC-V general registers except PC and MODE. The PC register represents program counter whereas the MODE register represent VCPU privilege mode (i.e. S/U-mode). The CSRs available to user-space are SSTATUS, SIE, STVEC, SSCRATCH, SEPC, SCAUSE, STVAL, SIP, and SATP. All of these are read/write registers. In future, more VCPU register types will be added (such as FP) for the KVM_GET_ONE_REG/KVM_SET_ONE_REG ioctls. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:04 +05:30
struct kvm_vcpu *vcpu = filp->private_data;
void __user *argp = (void __user *)arg;
long r = -EINVAL;
switch (ioctl) {
case KVM_SET_ONE_REG:
case KVM_GET_ONE_REG: {
struct kvm_one_reg reg;
r = -EFAULT;
if (copy_from_user(&reg, argp, sizeof(reg)))
break;
if (ioctl == KVM_SET_ONE_REG)
r = kvm_riscv_vcpu_set_reg(vcpu, &reg);
else
r = kvm_riscv_vcpu_get_reg(vcpu, &reg);
break;
}
default:
break;
}
return r;
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
}
int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
struct kvm_sregs *sregs)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
struct kvm_sregs *sregs)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
struct kvm_translation *tr)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
return -EINVAL;
}
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
void kvm_riscv_vcpu_flush_interrupts(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
unsigned long mask, val;
if (READ_ONCE(vcpu->arch.irqs_pending_mask)) {
mask = xchg_acquire(&vcpu->arch.irqs_pending_mask, 0);
val = READ_ONCE(vcpu->arch.irqs_pending) & mask;
csr->hvip &= ~mask;
csr->hvip |= val;
}
}
void kvm_riscv_vcpu_sync_interrupts(struct kvm_vcpu *vcpu)
{
unsigned long hvip;
struct kvm_vcpu_arch *v = &vcpu->arch;
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
/* Read current HVIP and VSIE CSRs */
csr->vsie = csr_read(CSR_VSIE);
/* Sync-up HVIP.VSSIP bit changes does by Guest */
hvip = csr_read(CSR_HVIP);
if ((csr->hvip ^ hvip) & (1UL << IRQ_VS_SOFT)) {
if (hvip & (1UL << IRQ_VS_SOFT)) {
if (!test_and_set_bit(IRQ_VS_SOFT,
&v->irqs_pending_mask))
set_bit(IRQ_VS_SOFT, &v->irqs_pending);
} else {
if (!test_and_set_bit(IRQ_VS_SOFT,
&v->irqs_pending_mask))
clear_bit(IRQ_VS_SOFT, &v->irqs_pending);
}
}
}
int kvm_riscv_vcpu_set_interrupt(struct kvm_vcpu *vcpu, unsigned int irq)
{
if (irq != IRQ_VS_SOFT &&
irq != IRQ_VS_TIMER &&
irq != IRQ_VS_EXT)
return -EINVAL;
set_bit(irq, &vcpu->arch.irqs_pending);
smp_mb__before_atomic();
set_bit(irq, &vcpu->arch.irqs_pending_mask);
kvm_vcpu_kick(vcpu);
return 0;
}
int kvm_riscv_vcpu_unset_interrupt(struct kvm_vcpu *vcpu, unsigned int irq)
{
if (irq != IRQ_VS_SOFT &&
irq != IRQ_VS_TIMER &&
irq != IRQ_VS_EXT)
return -EINVAL;
clear_bit(irq, &vcpu->arch.irqs_pending);
smp_mb__before_atomic();
set_bit(irq, &vcpu->arch.irqs_pending_mask);
return 0;
}
bool kvm_riscv_vcpu_has_interrupts(struct kvm_vcpu *vcpu, unsigned long mask)
{
unsigned long ie = ((vcpu->arch.guest_csr.vsie & VSIP_VALID_MASK)
<< VSIP_TO_HVIP_SHIFT) & mask;
return (READ_ONCE(vcpu->arch.irqs_pending) & ie) ? true : false;
}
void kvm_riscv_vcpu_power_off(struct kvm_vcpu *vcpu)
{
vcpu->arch.power_off = true;
kvm_make_request(KVM_REQ_SLEEP, vcpu);
kvm_vcpu_kick(vcpu);
}
void kvm_riscv_vcpu_power_on(struct kvm_vcpu *vcpu)
{
vcpu->arch.power_off = false;
kvm_vcpu_wake_up(vcpu);
}
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state)
{
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
if (vcpu->arch.power_off)
mp_state->mp_state = KVM_MP_STATE_STOPPED;
else
mp_state->mp_state = KVM_MP_STATE_RUNNABLE;
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
return 0;
}
int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state)
{
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
int ret = 0;
switch (mp_state->mp_state) {
case KVM_MP_STATE_RUNNABLE:
vcpu->arch.power_off = false;
break;
case KVM_MP_STATE_STOPPED:
kvm_riscv_vcpu_power_off(vcpu);
break;
default:
ret = -EINVAL;
}
return ret;
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
}
int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
struct kvm_guest_debug *dbg)
{
/* TODO; To be implemented later. */
return -EINVAL;
}
RISC-V: KVM: Add support for Svpbmt inside Guest/VM The Guest/VM can use Svpbmt in VS-stage page tables when allowed by the Hypervisor using the henvcfg.PBMTE bit. We add Svpbmt support for the KVM Guest/VM which can be enabled/disabled by the KVM user-space (QEMU/KVMTOOL) using the ISA extension ONE_REG interface. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:15:18 +05:30
static void kvm_riscv_vcpu_update_config(const unsigned long *isa)
{
u64 henvcfg = 0;
if (__riscv_isa_extension_available(isa, RISCV_ISA_EXT_SVPBMT))
henvcfg |= ENVCFG_PBMTE;
RISC-V: KVM: Support sstc extension Sstc extension allows the guest to program the vstimecmp CSR directly instead of making an SBI call to the hypervisor to program the next event. The timer interrupt is also directly injected to the guest by the hardware in this case. To maintain backward compatibility, the hypervisors also update the vstimecmp in an SBI set_time call if the hardware supports it. Thus, the older kernels in guest also take advantage of the sstc extension. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atishp@rivosinc.com> Acked-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/all/CAAhSdy2mb6wyqy0NAn9BcTWKMYEc0Z4zU3s3j7oNqBz6eDQ9sg@mail.gmail.com/ Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-07-22 09:50:47 -07:00
if (__riscv_isa_extension_available(isa, RISCV_ISA_EXT_SSTC))
henvcfg |= ENVCFG_STCE;
RISC-V: KVM: Add support for Svpbmt inside Guest/VM The Guest/VM can use Svpbmt in VS-stage page tables when allowed by the Hypervisor using the henvcfg.PBMTE bit. We add Svpbmt support for the KVM Guest/VM which can be enabled/disabled by the KVM user-space (QEMU/KVMTOOL) using the ISA extension ONE_REG interface. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:15:18 +05:30
csr_write(CSR_HENVCFG, henvcfg);
#ifdef CONFIG_32BIT
csr_write(CSR_HENVCFGH, henvcfg >> 32);
#endif
}
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
RISC-V: KVM: Implement VCPU world-switch This patch implements the VCPU world-switch for KVM RISC-V. The KVM RISC-V world-switch (i.e. __kvm_riscv_switch_to()) mostly switches general purpose registers, SSTATUS, STVEC, SSCRATCH and HSTATUS CSRs. Other CSRs are switched via vcpu_load() and vcpu_put() interface in kvm_arch_vcpu_load() and kvm_arch_vcpu_put() functions respectively. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:05 +05:30
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
csr_write(CSR_VSSTATUS, csr->vsstatus);
csr_write(CSR_VSIE, csr->vsie);
csr_write(CSR_VSTVEC, csr->vstvec);
csr_write(CSR_VSSCRATCH, csr->vsscratch);
csr_write(CSR_VSEPC, csr->vsepc);
csr_write(CSR_VSCAUSE, csr->vscause);
csr_write(CSR_VSTVAL, csr->vstval);
csr_write(CSR_HVIP, csr->hvip);
csr_write(CSR_VSATP, csr->vsatp);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
RISC-V: KVM: Add support for Svpbmt inside Guest/VM The Guest/VM can use Svpbmt in VS-stage page tables when allowed by the Hypervisor using the henvcfg.PBMTE bit. We add Svpbmt support for the KVM Guest/VM which can be enabled/disabled by the KVM user-space (QEMU/KVMTOOL) using the ISA extension ONE_REG interface. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:15:18 +05:30
kvm_riscv_vcpu_update_config(vcpu->arch.isa);
RISC-V: KVM: Use G-stage name for hypervisor page table The two-stage address translation defined by the RISC-V privileged specification defines: VS-stage (guest virtual address to guest physical address) programmed by the Guest OS and G-stage (guest physical addree to host physical address) programmed by the hypervisor. To align with above terminology, we replace "stage2" with "gstage" and "Stage2" with "G-stage" name everywhere in KVM RISC-V sources. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 10:43:30 +05:30
kvm_riscv_gstage_update_hgatp(vcpu);
RISC-V: KVM: Implement VCPU world-switch This patch implements the VCPU world-switch for KVM RISC-V. The KVM RISC-V world-switch (i.e. __kvm_riscv_switch_to()) mostly switches general purpose registers, SSTATUS, STVEC, SSCRATCH and HSTATUS CSRs. Other CSRs are switched via vcpu_load() and vcpu_put() interface in kvm_arch_vcpu_load() and kvm_arch_vcpu_put() functions respectively. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:05 +05:30
RISC-V: KVM: Add timer functionality The RISC-V hypervisor specification doesn't have any virtual timer feature. Due to this, the guest VCPU timer will be programmed via SBI calls. The host will use a separate hrtimer event for each guest VCPU to provide timer functionality. We inject a virtual timer interrupt to the guest VCPU whenever the guest VCPU hrtimer event expires. This patch adds guest VCPU timer implementation along with ONE_REG interface to access VCPU timer state from user space. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:11 +05:30
kvm_riscv_vcpu_timer_restore(vcpu);
RISC-V: KVM: FP lazy save/restore This patch adds floating point (F and D extension) context save/restore for guest VCPUs. The FP context is saved and restored lazily only when kernel enter/exits the in-kernel run loop and not during the KVM world switch. This way FP save/restore has minimal impact on KVM performance. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:12 +05:30
kvm_riscv_vcpu_host_fp_save(&vcpu->arch.host_context);
kvm_riscv_vcpu_guest_fp_restore(&vcpu->arch.guest_context,
vcpu->arch.isa);
RISC-V: KVM: Implement VCPU world-switch This patch implements the VCPU world-switch for KVM RISC-V. The KVM RISC-V world-switch (i.e. __kvm_riscv_switch_to()) mostly switches general purpose registers, SSTATUS, STVEC, SSCRATCH and HSTATUS CSRs. Other CSRs are switched via vcpu_load() and vcpu_put() interface in kvm_arch_vcpu_load() and kvm_arch_vcpu_put() functions respectively. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:05 +05:30
vcpu->cpu = cpu;
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
}
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
RISC-V: KVM: Implement VCPU world-switch This patch implements the VCPU world-switch for KVM RISC-V. The KVM RISC-V world-switch (i.e. __kvm_riscv_switch_to()) mostly switches general purpose registers, SSTATUS, STVEC, SSCRATCH and HSTATUS CSRs. Other CSRs are switched via vcpu_load() and vcpu_put() interface in kvm_arch_vcpu_load() and kvm_arch_vcpu_put() functions respectively. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:05 +05:30
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
vcpu->cpu = -1;
RISC-V: KVM: FP lazy save/restore This patch adds floating point (F and D extension) context save/restore for guest VCPUs. The FP context is saved and restored lazily only when kernel enter/exits the in-kernel run loop and not during the KVM world switch. This way FP save/restore has minimal impact on KVM performance. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:12 +05:30
kvm_riscv_vcpu_guest_fp_save(&vcpu->arch.guest_context,
vcpu->arch.isa);
kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context);
RISC-V: KVM: Support sstc extension Sstc extension allows the guest to program the vstimecmp CSR directly instead of making an SBI call to the hypervisor to program the next event. The timer interrupt is also directly injected to the guest by the hardware in this case. To maintain backward compatibility, the hypervisors also update the vstimecmp in an SBI set_time call if the hardware supports it. Thus, the older kernels in guest also take advantage of the sstc extension. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atishp@rivosinc.com> Acked-by: Anup Patel <anup@brainfault.org> Link: https://lore.kernel.org/all/CAAhSdy2mb6wyqy0NAn9BcTWKMYEc0Z4zU3s3j7oNqBz6eDQ9sg@mail.gmail.com/ Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-07-22 09:50:47 -07:00
kvm_riscv_vcpu_timer_save(vcpu);
RISC-V: KVM: Implement VCPU world-switch This patch implements the VCPU world-switch for KVM RISC-V. The KVM RISC-V world-switch (i.e. __kvm_riscv_switch_to()) mostly switches general purpose registers, SSTATUS, STVEC, SSCRATCH and HSTATUS CSRs. Other CSRs are switched via vcpu_load() and vcpu_put() interface in kvm_arch_vcpu_load() and kvm_arch_vcpu_put() functions respectively. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:05 +05:30
csr->vsstatus = csr_read(CSR_VSSTATUS);
csr->vsie = csr_read(CSR_VSIE);
csr->vstvec = csr_read(CSR_VSTVEC);
csr->vsscratch = csr_read(CSR_VSSCRATCH);
csr->vsepc = csr_read(CSR_VSEPC);
csr->vscause = csr_read(CSR_VSCAUSE);
csr->vstval = csr_read(CSR_VSTVAL);
csr->hvip = csr_read(CSR_HVIP);
csr->vsatp = csr_read(CSR_VSATP);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
}
static void kvm_riscv_check_vcpu_requests(struct kvm_vcpu *vcpu)
{
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
if (kvm_request_pending(vcpu)) {
if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) {
RISC-V: KVM: Fix SRCU deadlock caused by kvm_riscv_check_vcpu_requests() The kvm_riscv_check_vcpu_requests() is called with SRCU read lock held and for KVM_REQ_SLEEP request it will block the VCPU without releasing SRCU read lock. This causes KVM ioctls (such as KVM_IOEVENTFD) from other VCPUs of the same Guest/VM to hang/deadlock if there is any synchronize_srcu() or synchronize_srcu_expedited() in the path. To fix the above in kvm_riscv_check_vcpu_requests(), we should do SRCU read unlock before blocking the VCPU and do SRCU read lock after VCPU wakeup. Fixes: cce69aff689e ("RISC-V: KVM: Implement VCPU interrupts and requests handling") Reported-by: Bin Meng <bmeng.cn@gmail.com> Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Tested-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com> Tested-by: Bin Meng <bmeng.cn@gmail.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-11 09:36:32 +05:30
kvm_vcpu_srcu_read_unlock(vcpu);
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
rcuwait_wait_event(wait,
(!vcpu->arch.power_off) && (!vcpu->arch.pause),
TASK_INTERRUPTIBLE);
RISC-V: KVM: Fix SRCU deadlock caused by kvm_riscv_check_vcpu_requests() The kvm_riscv_check_vcpu_requests() is called with SRCU read lock held and for KVM_REQ_SLEEP request it will block the VCPU without releasing SRCU read lock. This causes KVM ioctls (such as KVM_IOEVENTFD) from other VCPUs of the same Guest/VM to hang/deadlock if there is any synchronize_srcu() or synchronize_srcu_expedited() in the path. To fix the above in kvm_riscv_check_vcpu_requests(), we should do SRCU read unlock before blocking the VCPU and do SRCU read lock after VCPU wakeup. Fixes: cce69aff689e ("RISC-V: KVM: Implement VCPU interrupts and requests handling") Reported-by: Bin Meng <bmeng.cn@gmail.com> Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Tested-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com> Tested-by: Bin Meng <bmeng.cn@gmail.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-11 09:36:32 +05:30
kvm_vcpu_srcu_read_lock(vcpu);
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
if (vcpu->arch.power_off || vcpu->arch.pause) {
/*
* Awaken to handle a signal, request to
* sleep again later.
*/
kvm_make_request(KVM_REQ_SLEEP, vcpu);
}
}
if (kvm_check_request(KVM_REQ_VCPU_RESET, vcpu))
kvm_riscv_reset_vcpu(vcpu);
RISC-V: KVM: Implement VMID allocator We implement a simple VMID allocator for Guests/VMs which: 1. Detects number of VMID bits at boot-time 2. Uses atomic number to track VMID version and increments VMID version whenever we run-out of VMIDs 3. Flushes Guest TLBs on all host CPUs whenever we run-out of VMIDs 4. Force updates HW Stage2 VMID for each Guest VCPU whenever VMID changes using VCPU request KVM_REQ_UPDATE_HGATP Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:08 +05:30
if (kvm_check_request(KVM_REQ_UPDATE_HGATP, vcpu))
RISC-V: KVM: Use G-stage name for hypervisor page table The two-stage address translation defined by the RISC-V privileged specification defines: VS-stage (guest virtual address to guest physical address) programmed by the Guest OS and G-stage (guest physical addree to host physical address) programmed by the hypervisor. To align with above terminology, we replace "stage2" with "gstage" and "Stage2" with "G-stage" name everywhere in KVM RISC-V sources. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 10:43:30 +05:30
kvm_riscv_gstage_update_hgatp(vcpu);
RISC-V: KVM: Implement VMID allocator We implement a simple VMID allocator for Guests/VMs which: 1. Detects number of VMID bits at boot-time 2. Uses atomic number to track VMID version and increments VMID version whenever we run-out of VMIDs 3. Flushes Guest TLBs on all host CPUs whenever we run-out of VMIDs 4. Force updates HW Stage2 VMID for each Guest VCPU whenever VMID changes using VCPU request KVM_REQ_UPDATE_HGATP Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:08 +05:30
RISC-V: KVM: Add remote HFENCE functions based on VCPU requests The generic KVM has support for VCPU requests which can be used to do arch-specific work in the run-loop. We introduce remote HFENCE functions which will internally use VCPU requests instead of host SBI calls. Advantages of doing remote HFENCEs as VCPU requests are: 1) Multiple VCPUs of a Guest may be running on different Host CPUs so it is not always possible to determine the Host CPU mask for doing Host SBI call. For example, when VCPU X wants to do HFENCE on VCPU Y, it is possible that VCPU Y is blocked or in user-space (i.e. vcpu->cpu < 0). 2) To support nested virtualization, we will be having a separate shadow G-stage for each VCPU and a common host G-stage for the entire Guest/VM. The VCPU requests based remote HFENCEs helps us easily synchronize the common host G-stage and shadow G-stage of each VCPU without any additional IPI calls. This is also a preparatory patch for upcoming nested virtualization support where we will be having a shadow G-stage page table for each Guest VCPU. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 10:44:05 +05:30
if (kvm_check_request(KVM_REQ_FENCE_I, vcpu))
kvm_riscv_fence_i_process(vcpu);
/*
* The generic KVM_REQ_TLB_FLUSH is same as
* KVM_REQ_HFENCE_GVMA_VMID_ALL
*/
if (kvm_check_request(KVM_REQ_HFENCE_GVMA_VMID_ALL, vcpu))
kvm_riscv_hfence_gvma_vmid_all_process(vcpu);
if (kvm_check_request(KVM_REQ_HFENCE_VVMA_ALL, vcpu))
kvm_riscv_hfence_vvma_all_process(vcpu);
if (kvm_check_request(KVM_REQ_HFENCE, vcpu))
kvm_riscv_hfence_process(vcpu);
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
}
}
static void kvm_riscv_update_hvip(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr;
csr_write(CSR_HVIP, csr->hvip);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
}
kvm/riscv: rework guest entry logic In kvm_arch_vcpu_ioctl_run() we enter an RCU extended quiescent state (EQS) by calling guest_enter_irqoff(), and unmask IRQs prior to exiting the EQS by calling guest_exit(). As the IRQ entry code will not wake RCU in this case, we may run the core IRQ code and IRQ handler without RCU watching, leading to various potential problems. Additionally, we do not inform lockdep or tracing that interrupts will be enabled during guest execution, which caan lead to misleading traces and warnings that interrupts have been enabled for overly-long periods. This patch fixes these issues by using the new timing and context entry/exit helpers to ensure that interrupts are handled during guest vtime but with RCU watching, with a sequence: guest_timing_enter_irqoff(); guest_state_enter_irqoff(); < run the vcpu > guest_state_exit_irqoff(); < take any pending IRQs > guest_timing_exit_irqoff(); Since instrumentation may make use of RCU, we must also ensure that no instrumented code is run during the EQS. I've split out the critical section into a new kvm_riscv_enter_exit_vcpu() helper which is marked noinstr. Fixes: 99cdc6c18c2d815e ("RISC-V: Add initial skeletal KVM support") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Anup Patel <anup@brainfault.org> Cc: Atish Patra <atishp@atishpatra.org> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Tested-by: Anup Patel <anup@brainfault.org> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-02-01 13:29:25 +00:00
/*
* Actually run the vCPU, entering an RCU extended quiescent state (EQS) while
* the vCPU is running.
*
* This must be noinstr as instrumentation may make use of RCU, and this is not
* safe during the EQS.
*/
static void noinstr kvm_riscv_vcpu_enter_exit(struct kvm_vcpu *vcpu)
{
guest_state_enter_irqoff();
__kvm_riscv_switch_to(&vcpu->arch);
RISC-V: KVM: Cleanup stale TLB entries when host CPU changes On RISC-V platforms with hardware VMID support, we share same VMID for all VCPUs of a particular Guest/VM. This means we might have stale G-stage TLB entries on the current Host CPU due to some other VCPU of the same Guest which ran previously on the current Host CPU. To cleanup stale TLB entries, we simply flush all G-stage TLB entries by VMID whenever underlying Host CPU changes for a VCPU. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 10:44:11 +05:30
vcpu->arch.last_exit_cpu = vcpu->cpu;
kvm/riscv: rework guest entry logic In kvm_arch_vcpu_ioctl_run() we enter an RCU extended quiescent state (EQS) by calling guest_enter_irqoff(), and unmask IRQs prior to exiting the EQS by calling guest_exit(). As the IRQ entry code will not wake RCU in this case, we may run the core IRQ code and IRQ handler without RCU watching, leading to various potential problems. Additionally, we do not inform lockdep or tracing that interrupts will be enabled during guest execution, which caan lead to misleading traces and warnings that interrupts have been enabled for overly-long periods. This patch fixes these issues by using the new timing and context entry/exit helpers to ensure that interrupts are handled during guest vtime but with RCU watching, with a sequence: guest_timing_enter_irqoff(); guest_state_enter_irqoff(); < run the vcpu > guest_state_exit_irqoff(); < take any pending IRQs > guest_timing_exit_irqoff(); Since instrumentation may make use of RCU, we must also ensure that no instrumented code is run during the EQS. I've split out the critical section into a new kvm_riscv_enter_exit_vcpu() helper which is marked noinstr. Fixes: 99cdc6c18c2d815e ("RISC-V: Add initial skeletal KVM support") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Anup Patel <anup@brainfault.org> Cc: Atish Patra <atishp@atishpatra.org> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Tested-by: Anup Patel <anup@brainfault.org> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-02-01 13:29:25 +00:00
guest_state_exit_irqoff();
}
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu)
{
int ret;
struct kvm_cpu_trap trap;
struct kvm_run *run = vcpu->run;
RISC-V: KVM: Implement VCPU create, init and destroy functions This patch implements VCPU create, init and destroy functions required by generic KVM module. We don't have much dynamic resources in struct kvm_vcpu_arch so these functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:02 +05:30
/* Mark this VCPU ran at least once */
vcpu->arch.ran_atleast_once = true;
KVM: Add helpers to wrap vcpu->srcu_idx and yell if it's abused Add wrappers to acquire/release KVM's SRCU lock when stashing the index in vcpu->src_idx, along with rudimentary detection of illegal usage, e.g. re-acquiring SRCU and thus overwriting vcpu->src_idx. Because the SRCU index is (currently) either 0 or 1, illegal nesting bugs can go unnoticed for quite some time and only cause problems when the nested lock happens to get a different index. Wrap the WARNs in PROVE_RCU=y, and make them ONCE, otherwise KVM will likely yell so loudly that it will bring the kernel to its knees. Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Fabiano Rosas <farosas@linux.ibm.com> Message-Id: <20220415004343.2203171-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-15 00:43:43 +00:00
kvm_vcpu_srcu_read_lock(vcpu);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
RISC-V: KVM: Add extensible CSR emulation framework We add an extensible CSR emulation framework which is based upon the existing system instruction emulation. This will be useful to upcoming AIA, PMU, Nested and other virtualization features. The CSR emulation framework also has provision to emulate CSR in user space but this will be used only in very specific cases such as AIA IMSIC CSR emulation in user space or vendor specific CSR emulation in user space. By default, all CSRs not handled by KVM RISC-V will be redirected back to Guest VCPU as illegal instruction trap. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:53 +05:30
switch (run->exit_reason) {
case KVM_EXIT_MMIO:
/* Process MMIO value returned from user-space */
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
ret = kvm_riscv_vcpu_mmio_return(vcpu, vcpu->run);
RISC-V: KVM: Add extensible CSR emulation framework We add an extensible CSR emulation framework which is based upon the existing system instruction emulation. This will be useful to upcoming AIA, PMU, Nested and other virtualization features. The CSR emulation framework also has provision to emulate CSR in user space but this will be used only in very specific cases such as AIA IMSIC CSR emulation in user space or vendor specific CSR emulation in user space. By default, all CSRs not handled by KVM RISC-V will be redirected back to Guest VCPU as illegal instruction trap. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:53 +05:30
break;
case KVM_EXIT_RISCV_SBI:
/* Process SBI value returned from user-space */
RISC-V: KVM: Add SBI v0.1 support The KVM host kernel is running in HS-mode needs so we need to handle the SBI calls coming from guest kernel running in VS-mode. This patch adds SBI v0.1 support in KVM RISC-V. Almost all SBI v0.1 calls are implemented in KVM kernel module except GETCHAR and PUTCHART calls which are forwarded to user space because these calls cannot be implemented in kernel space. In future, when we implement SBI v0.2 for Guest, we will forward SBI v0.2 experimental and vendor extension calls to user space. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:14 +05:30
ret = kvm_riscv_vcpu_sbi_return(vcpu, vcpu->run);
RISC-V: KVM: Add extensible CSR emulation framework We add an extensible CSR emulation framework which is based upon the existing system instruction emulation. This will be useful to upcoming AIA, PMU, Nested and other virtualization features. The CSR emulation framework also has provision to emulate CSR in user space but this will be used only in very specific cases such as AIA IMSIC CSR emulation in user space or vendor specific CSR emulation in user space. By default, all CSRs not handled by KVM RISC-V will be redirected back to Guest VCPU as illegal instruction trap. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:53 +05:30
break;
case KVM_EXIT_RISCV_CSR:
/* Process CSR value returned from user-space */
ret = kvm_riscv_vcpu_csr_return(vcpu, vcpu->run);
break;
default:
ret = 0;
break;
}
if (ret) {
kvm_vcpu_srcu_read_unlock(vcpu);
return ret;
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
}
if (run->immediate_exit) {
KVM: Add helpers to wrap vcpu->srcu_idx and yell if it's abused Add wrappers to acquire/release KVM's SRCU lock when stashing the index in vcpu->src_idx, along with rudimentary detection of illegal usage, e.g. re-acquiring SRCU and thus overwriting vcpu->src_idx. Because the SRCU index is (currently) either 0 or 1, illegal nesting bugs can go unnoticed for quite some time and only cause problems when the nested lock happens to get a different index. Wrap the WARNs in PROVE_RCU=y, and make them ONCE, otherwise KVM will likely yell so loudly that it will bring the kernel to its knees. Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Fabiano Rosas <farosas@linux.ibm.com> Message-Id: <20220415004343.2203171-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-15 00:43:43 +00:00
kvm_vcpu_srcu_read_unlock(vcpu);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
return -EINTR;
}
vcpu_load(vcpu);
kvm_sigset_activate(vcpu);
ret = 1;
run->exit_reason = KVM_EXIT_UNKNOWN;
while (ret > 0) {
/* Check conditions before entering the guest */
cond_resched();
RISC-V: KVM: Use G-stage name for hypervisor page table The two-stage address translation defined by the RISC-V privileged specification defines: VS-stage (guest virtual address to guest physical address) programmed by the Guest OS and G-stage (guest physical addree to host physical address) programmed by the hypervisor. To align with above terminology, we replace "stage2" with "gstage" and "Stage2" with "G-stage" name everywhere in KVM RISC-V sources. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 10:43:30 +05:30
kvm_riscv_gstage_vmid_update(vcpu);
RISC-V: KVM: Implement VMID allocator We implement a simple VMID allocator for Guests/VMs which: 1. Detects number of VMID bits at boot-time 2. Uses atomic number to track VMID version and increments VMID version whenever we run-out of VMIDs 3. Flushes Guest TLBs on all host CPUs whenever we run-out of VMIDs 4. Force updates HW Stage2 VMID for each Guest VCPU whenever VMID changes using VCPU request KVM_REQ_UPDATE_HGATP Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:08 +05:30
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
kvm_riscv_check_vcpu_requests(vcpu);
local_irq_disable();
/*
* Exit if we have a signal pending so that we can deliver
* the signal to user space.
*/
if (signal_pending(current)) {
ret = -EINTR;
run->exit_reason = KVM_EXIT_INTR;
}
/*
* Ensure we set mode to IN_GUEST_MODE after we disable
* interrupts and before the final VCPU requests check.
* See the comment in kvm_vcpu_exiting_guest_mode() and
Documentation: update vcpu-requests.rst reference Changeset 2f5947dfcaec ("Documentation: move Documentation/virtual to Documentation/virt") renamed: Documentation/virtual/kvm/vcpu-requests.rst to: Documentation/virt/kvm/vcpu-requests.rst. Update its cross-reference accordingly. Fixes: 2f5947dfcaec ("Documentation: move Documentation/virtual to Documentation/virt") Reviewed-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2021-11-16 12:11:22 +00:00
* Documentation/virt/kvm/vcpu-requests.rst
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
*/
vcpu->mode = IN_GUEST_MODE;
KVM: Add helpers to wrap vcpu->srcu_idx and yell if it's abused Add wrappers to acquire/release KVM's SRCU lock when stashing the index in vcpu->src_idx, along with rudimentary detection of illegal usage, e.g. re-acquiring SRCU and thus overwriting vcpu->src_idx. Because the SRCU index is (currently) either 0 or 1, illegal nesting bugs can go unnoticed for quite some time and only cause problems when the nested lock happens to get a different index. Wrap the WARNs in PROVE_RCU=y, and make them ONCE, otherwise KVM will likely yell so loudly that it will bring the kernel to its knees. Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Fabiano Rosas <farosas@linux.ibm.com> Message-Id: <20220415004343.2203171-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-15 00:43:43 +00:00
kvm_vcpu_srcu_read_unlock(vcpu);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
smp_mb__after_srcu_read_unlock();
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
/*
* We might have got VCPU interrupts updated asynchronously
* so update it in HW.
*/
kvm_riscv_vcpu_flush_interrupts(vcpu);
/* Update HVIP CSR for current CPU */
kvm_riscv_update_hvip(vcpu);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
if (ret <= 0 ||
RISC-V: KVM: Use G-stage name for hypervisor page table The two-stage address translation defined by the RISC-V privileged specification defines: VS-stage (guest virtual address to guest physical address) programmed by the Guest OS and G-stage (guest physical addree to host physical address) programmed by the hypervisor. To align with above terminology, we replace "stage2" with "gstage" and "Stage2" with "G-stage" name everywhere in KVM RISC-V sources. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 10:43:30 +05:30
kvm_riscv_gstage_vmid_ver_changed(&vcpu->kvm->arch.vmid) ||
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
kvm_request_pending(vcpu)) {
vcpu->mode = OUTSIDE_GUEST_MODE;
local_irq_enable();
KVM: Add helpers to wrap vcpu->srcu_idx and yell if it's abused Add wrappers to acquire/release KVM's SRCU lock when stashing the index in vcpu->src_idx, along with rudimentary detection of illegal usage, e.g. re-acquiring SRCU and thus overwriting vcpu->src_idx. Because the SRCU index is (currently) either 0 or 1, illegal nesting bugs can go unnoticed for quite some time and only cause problems when the nested lock happens to get a different index. Wrap the WARNs in PROVE_RCU=y, and make them ONCE, otherwise KVM will likely yell so loudly that it will bring the kernel to its knees. Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Fabiano Rosas <farosas@linux.ibm.com> Message-Id: <20220415004343.2203171-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-15 00:43:43 +00:00
kvm_vcpu_srcu_read_lock(vcpu);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
continue;
}
RISC-V: KVM: Cleanup stale TLB entries when host CPU changes On RISC-V platforms with hardware VMID support, we share same VMID for all VCPUs of a particular Guest/VM. This means we might have stale G-stage TLB entries on the current Host CPU due to some other VCPU of the same Guest which ran previously on the current Host CPU. To cleanup stale TLB entries, we simply flush all G-stage TLB entries by VMID whenever underlying Host CPU changes for a VCPU. Signed-off-by: Anup Patel <apatel@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-05-09 10:44:11 +05:30
/*
* Cleanup stale TLB enteries
*
* Note: This should be done after G-stage VMID has been
* updated using kvm_riscv_gstage_vmid_ver_changed()
*/
kvm_riscv_local_tlb_sanitize(vcpu);
kvm/riscv: rework guest entry logic In kvm_arch_vcpu_ioctl_run() we enter an RCU extended quiescent state (EQS) by calling guest_enter_irqoff(), and unmask IRQs prior to exiting the EQS by calling guest_exit(). As the IRQ entry code will not wake RCU in this case, we may run the core IRQ code and IRQ handler without RCU watching, leading to various potential problems. Additionally, we do not inform lockdep or tracing that interrupts will be enabled during guest execution, which caan lead to misleading traces and warnings that interrupts have been enabled for overly-long periods. This patch fixes these issues by using the new timing and context entry/exit helpers to ensure that interrupts are handled during guest vtime but with RCU watching, with a sequence: guest_timing_enter_irqoff(); guest_state_enter_irqoff(); < run the vcpu > guest_state_exit_irqoff(); < take any pending IRQs > guest_timing_exit_irqoff(); Since instrumentation may make use of RCU, we must also ensure that no instrumented code is run during the EQS. I've split out the critical section into a new kvm_riscv_enter_exit_vcpu() helper which is marked noinstr. Fixes: 99cdc6c18c2d815e ("RISC-V: Add initial skeletal KVM support") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Anup Patel <anup@brainfault.org> Cc: Atish Patra <atishp@atishpatra.org> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Tested-by: Anup Patel <anup@brainfault.org> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-02-01 13:29:25 +00:00
guest_timing_enter_irqoff();
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
kvm/riscv: rework guest entry logic In kvm_arch_vcpu_ioctl_run() we enter an RCU extended quiescent state (EQS) by calling guest_enter_irqoff(), and unmask IRQs prior to exiting the EQS by calling guest_exit(). As the IRQ entry code will not wake RCU in this case, we may run the core IRQ code and IRQ handler without RCU watching, leading to various potential problems. Additionally, we do not inform lockdep or tracing that interrupts will be enabled during guest execution, which caan lead to misleading traces and warnings that interrupts have been enabled for overly-long periods. This patch fixes these issues by using the new timing and context entry/exit helpers to ensure that interrupts are handled during guest vtime but with RCU watching, with a sequence: guest_timing_enter_irqoff(); guest_state_enter_irqoff(); < run the vcpu > guest_state_exit_irqoff(); < take any pending IRQs > guest_timing_exit_irqoff(); Since instrumentation may make use of RCU, we must also ensure that no instrumented code is run during the EQS. I've split out the critical section into a new kvm_riscv_enter_exit_vcpu() helper which is marked noinstr. Fixes: 99cdc6c18c2d815e ("RISC-V: Add initial skeletal KVM support") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Anup Patel <anup@brainfault.org> Cc: Atish Patra <atishp@atishpatra.org> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Tested-by: Anup Patel <anup@brainfault.org> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-02-01 13:29:25 +00:00
kvm_riscv_vcpu_enter_exit(vcpu);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
vcpu->mode = OUTSIDE_GUEST_MODE;
vcpu->stat.exits++;
/*
* Save SCAUSE, STVAL, HTVAL, and HTINST because we might
* get an interrupt between __kvm_riscv_switch_to() and
* local_irq_enable() which can potentially change CSRs.
*/
RISC-V: KVM: Implement VCPU create, init and destroy functions This patch implements VCPU create, init and destroy functions required by generic KVM module. We don't have much dynamic resources in struct kvm_vcpu_arch so these functions are quite simple for KVM RISC-V. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:02 +05:30
trap.sepc = vcpu->arch.guest_context.sepc;
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
trap.scause = csr_read(CSR_SCAUSE);
trap.stval = csr_read(CSR_STVAL);
trap.htval = csr_read(CSR_HTVAL);
trap.htinst = csr_read(CSR_HTINST);
RISC-V: KVM: Implement VCPU interrupts and requests handling This patch implements VCPU interrupts and requests which are both asynchronous events. The VCPU interrupts can be set/unset using KVM_INTERRUPT ioctl from user-space. In future, the in-kernel IRQCHIP emulation will use kvm_riscv_vcpu_set_interrupt() and kvm_riscv_vcpu_unset_interrupt() functions to set/unset VCPU interrupts. Important VCPU requests implemented by this patch are: KVM_REQ_SLEEP - set whenever VCPU itself goes to sleep state KVM_REQ_VCPU_RESET - set whenever VCPU reset is requested The WFI trap-n-emulate (added later) will use KVM_REQ_SLEEP request and kvm_riscv_vcpu_has_interrupt() function. The KVM_REQ_VCPU_RESET request will be used by SBI emulation (added later) to power-up a VCPU in power-off state. The user-space can use the GET_MPSTATE/SET_MPSTATE ioctls to get/set power state of a VCPU. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:03 +05:30
/* Syncup interrupts state with HW */
kvm_riscv_vcpu_sync_interrupts(vcpu);
RISC-V: KVM: move preempt_disable() call in kvm_arch_vcpu_ioctl_run local_irq_disable provides stronger guarantees than preempt_disable so calling the latter is redundant when interrupts are disabled. Instead, explicitly disable preemption right before interrupts are enabled/disabled to ensure that the time accounted in guest_timing_exit_irqoff includes time taken by the guest or interrupts. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-07-29 17:14:34 +05:30
preempt_disable();
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
/*
kvm/riscv: rework guest entry logic In kvm_arch_vcpu_ioctl_run() we enter an RCU extended quiescent state (EQS) by calling guest_enter_irqoff(), and unmask IRQs prior to exiting the EQS by calling guest_exit(). As the IRQ entry code will not wake RCU in this case, we may run the core IRQ code and IRQ handler without RCU watching, leading to various potential problems. Additionally, we do not inform lockdep or tracing that interrupts will be enabled during guest execution, which caan lead to misleading traces and warnings that interrupts have been enabled for overly-long periods. This patch fixes these issues by using the new timing and context entry/exit helpers to ensure that interrupts are handled during guest vtime but with RCU watching, with a sequence: guest_timing_enter_irqoff(); guest_state_enter_irqoff(); < run the vcpu > guest_state_exit_irqoff(); < take any pending IRQs > guest_timing_exit_irqoff(); Since instrumentation may make use of RCU, we must also ensure that no instrumented code is run during the EQS. I've split out the critical section into a new kvm_riscv_enter_exit_vcpu() helper which is marked noinstr. Fixes: 99cdc6c18c2d815e ("RISC-V: Add initial skeletal KVM support") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Anup Patel <anup@brainfault.org> Cc: Atish Patra <atishp@atishpatra.org> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Tested-by: Anup Patel <anup@brainfault.org> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-02-01 13:29:25 +00:00
* We must ensure that any pending interrupts are taken before
* we exit guest timing so that timer ticks are accounted as
* guest time. Transiently unmask interrupts so that any
* pending interrupts are taken.
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
*
kvm/riscv: rework guest entry logic In kvm_arch_vcpu_ioctl_run() we enter an RCU extended quiescent state (EQS) by calling guest_enter_irqoff(), and unmask IRQs prior to exiting the EQS by calling guest_exit(). As the IRQ entry code will not wake RCU in this case, we may run the core IRQ code and IRQ handler without RCU watching, leading to various potential problems. Additionally, we do not inform lockdep or tracing that interrupts will be enabled during guest execution, which caan lead to misleading traces and warnings that interrupts have been enabled for overly-long periods. This patch fixes these issues by using the new timing and context entry/exit helpers to ensure that interrupts are handled during guest vtime but with RCU watching, with a sequence: guest_timing_enter_irqoff(); guest_state_enter_irqoff(); < run the vcpu > guest_state_exit_irqoff(); < take any pending IRQs > guest_timing_exit_irqoff(); Since instrumentation may make use of RCU, we must also ensure that no instrumented code is run during the EQS. I've split out the critical section into a new kvm_riscv_enter_exit_vcpu() helper which is marked noinstr. Fixes: 99cdc6c18c2d815e ("RISC-V: Add initial skeletal KVM support") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Anup Patel <anup@brainfault.org> Cc: Atish Patra <atishp@atishpatra.org> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Tested-by: Anup Patel <anup@brainfault.org> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-02-01 13:29:25 +00:00
* There's no barrier which ensures that pending interrupts are
* recognised, so we just hope that the CPU takes any pending
* interrupts between the enable and disable.
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
*/
local_irq_enable();
kvm/riscv: rework guest entry logic In kvm_arch_vcpu_ioctl_run() we enter an RCU extended quiescent state (EQS) by calling guest_enter_irqoff(), and unmask IRQs prior to exiting the EQS by calling guest_exit(). As the IRQ entry code will not wake RCU in this case, we may run the core IRQ code and IRQ handler without RCU watching, leading to various potential problems. Additionally, we do not inform lockdep or tracing that interrupts will be enabled during guest execution, which caan lead to misleading traces and warnings that interrupts have been enabled for overly-long periods. This patch fixes these issues by using the new timing and context entry/exit helpers to ensure that interrupts are handled during guest vtime but with RCU watching, with a sequence: guest_timing_enter_irqoff(); guest_state_enter_irqoff(); < run the vcpu > guest_state_exit_irqoff(); < take any pending IRQs > guest_timing_exit_irqoff(); Since instrumentation may make use of RCU, we must also ensure that no instrumented code is run during the EQS. I've split out the critical section into a new kvm_riscv_enter_exit_vcpu() helper which is marked noinstr. Fixes: 99cdc6c18c2d815e ("RISC-V: Add initial skeletal KVM support") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Anup Patel <anup@brainfault.org> Cc: Atish Patra <atishp@atishpatra.org> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Tested-by: Anup Patel <anup@brainfault.org> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-02-01 13:29:25 +00:00
local_irq_disable();
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
kvm/riscv: rework guest entry logic In kvm_arch_vcpu_ioctl_run() we enter an RCU extended quiescent state (EQS) by calling guest_enter_irqoff(), and unmask IRQs prior to exiting the EQS by calling guest_exit(). As the IRQ entry code will not wake RCU in this case, we may run the core IRQ code and IRQ handler without RCU watching, leading to various potential problems. Additionally, we do not inform lockdep or tracing that interrupts will be enabled during guest execution, which caan lead to misleading traces and warnings that interrupts have been enabled for overly-long periods. This patch fixes these issues by using the new timing and context entry/exit helpers to ensure that interrupts are handled during guest vtime but with RCU watching, with a sequence: guest_timing_enter_irqoff(); guest_state_enter_irqoff(); < run the vcpu > guest_state_exit_irqoff(); < take any pending IRQs > guest_timing_exit_irqoff(); Since instrumentation may make use of RCU, we must also ensure that no instrumented code is run during the EQS. I've split out the critical section into a new kvm_riscv_enter_exit_vcpu() helper which is marked noinstr. Fixes: 99cdc6c18c2d815e ("RISC-V: Add initial skeletal KVM support") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Anup Patel <anup@brainfault.org> Cc: Atish Patra <atishp@atishpatra.org> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Tested-by: Anup Patel <anup@brainfault.org> Signed-off-by: Anup Patel <anup@brainfault.org>
2022-02-01 13:29:25 +00:00
guest_timing_exit_irqoff();
local_irq_enable();
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
preempt_enable();
KVM: Add helpers to wrap vcpu->srcu_idx and yell if it's abused Add wrappers to acquire/release KVM's SRCU lock when stashing the index in vcpu->src_idx, along with rudimentary detection of illegal usage, e.g. re-acquiring SRCU and thus overwriting vcpu->src_idx. Because the SRCU index is (currently) either 0 or 1, illegal nesting bugs can go unnoticed for quite some time and only cause problems when the nested lock happens to get a different index. Wrap the WARNs in PROVE_RCU=y, and make them ONCE, otherwise KVM will likely yell so loudly that it will bring the kernel to its knees. Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Fabiano Rosas <farosas@linux.ibm.com> Message-Id: <20220415004343.2203171-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-15 00:43:43 +00:00
kvm_vcpu_srcu_read_lock(vcpu);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
ret = kvm_riscv_vcpu_exit(vcpu, run, &trap);
}
kvm_sigset_deactivate(vcpu);
vcpu_put(vcpu);
KVM: Add helpers to wrap vcpu->srcu_idx and yell if it's abused Add wrappers to acquire/release KVM's SRCU lock when stashing the index in vcpu->src_idx, along with rudimentary detection of illegal usage, e.g. re-acquiring SRCU and thus overwriting vcpu->src_idx. Because the SRCU index is (currently) either 0 or 1, illegal nesting bugs can go unnoticed for quite some time and only cause problems when the nested lock happens to get a different index. Wrap the WARNs in PROVE_RCU=y, and make them ONCE, otherwise KVM will likely yell so loudly that it will bring the kernel to its knees. Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Fabiano Rosas <farosas@linux.ibm.com> Message-Id: <20220415004343.2203171-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-15 00:43:43 +00:00
kvm_vcpu_srcu_read_unlock(vcpu);
RISC-V: Add initial skeletal KVM support This patch adds initial skeletal KVM RISC-V support which has: 1. A simple implementation of arch specific VM functions except kvm_vm_ioctl_get_dirty_log() which will implemeted in-future as part of stage2 page loging. 2. Stubs of required arch specific VCPU functions except kvm_arch_vcpu_ioctl_run() which is semi-complete and extended by subsequent patches. 3. Stubs for required arch specific stage2 MMU functions. Signed-off-by: Anup Patel <anup.patel@wdc.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alexander Graf <graf@amazon.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-09-27 17:10:01 +05:30
return ret;
}
Reference in New Issue Copy Permalink