diff options
Diffstat (limited to 'arch/riscv/kvm/vcpu.c')
| -rw-r--r-- | arch/riscv/kvm/vcpu.c | 825 |
1 files changed, 825 insertions, 0 deletions
diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c new file mode 100644 index 00000000000000..e3d3aed461840f --- /dev/null +++ b/arch/riscv/kvm/vcpu.c @@ -0,0 +1,825 @@ +// 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> +#include <linux/percpu.h> +#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), + 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), +}; + +#define KVM_RISCV_ISA_ALLOWED (riscv_isa_extension_mask(a) | \ + riscv_isa_extension_mask(c) | \ + riscv_isa_extension_mask(d) | \ + riscv_isa_extension_mask(f) | \ + riscv_isa_extension_mask(i) | \ + riscv_isa_extension_mask(m) | \ + riscv_isa_extension_mask(s) | \ + riscv_isa_extension_mask(u)) + +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; + + memcpy(csr, reset_csr, sizeof(*csr)); + + memcpy(cntx, reset_cntx, sizeof(*cntx)); + + kvm_riscv_vcpu_fp_reset(vcpu); + + kvm_riscv_vcpu_timer_reset(vcpu); + + WRITE_ONCE(vcpu->arch.irqs_pending, 0); + WRITE_ONCE(vcpu->arch.irqs_pending_mask, 0); +} + +int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) +{ + return 0; +} + +int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) +{ + struct kvm_cpu_context *cntx; + + /* Mark this VCPU never ran */ + vcpu->arch.ran_atleast_once = false; + + /* Setup ISA features available to VCPU */ + vcpu->arch.isa = riscv_isa_extension_base(NULL) & KVM_RISCV_ISA_ALLOWED; + + /* 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; + + /* Setup VCPU timer */ + kvm_riscv_vcpu_timer_init(vcpu); + + /* Reset VCPU */ + kvm_riscv_reset_vcpu(vcpu); + + return 0; +} + +void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) +{ +} + +void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) +{ + /* Cleanup VCPU timer */ + kvm_riscv_vcpu_timer_deinit(vcpu); + + /* Flush the pages pre-allocated for Stage2 page table mappings */ + kvm_riscv_stage2_flush_cache(vcpu); +} + +int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) +{ + return kvm_riscv_vcpu_has_interrupts(vcpu, 1UL << IRQ_VS_TIMER); +} + +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) +{ + return (kvm_riscv_vcpu_has_interrupts(vcpu, -1UL) && + !vcpu->arch.power_off && !vcpu->arch.pause); +} + +int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu) +{ + return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE; +} + +bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) +{ + return (vcpu->arch.guest_context.sstatus & SR_SPP) ? true : false; +} + +vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) +{ + return VM_FAULT_SIGBUS; +} + +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): + reg_val = vcpu->arch.isa; + break; + default: + return -EINVAL; + } + + if (copy_to_user(uaddr, ®_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); + unsigned long reg_val; + + if (KVM_REG_SIZE(reg->id) != sizeof(unsigned long)) + return -EINVAL; + + if (copy_from_user(®_val, uaddr, KVM_REG_SIZE(reg->id))) + return -EFAULT; + + switch (reg_num) { + case KVM_REG_RISCV_CONFIG_REG(isa): + if (!vcpu->arch.ran_atleast_once) { + vcpu->arch.isa = reg_val; + vcpu->arch.isa &= riscv_isa_extension_base(NULL); + vcpu->arch.isa &= KVM_RISCV_ISA_ALLOWED; + kvm_riscv_vcpu_fp_reset(vcpu); + } else { + return -EOPNOTSUPP; + } + break; + default: + return -EINVAL; + } + + 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, ®_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(®_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, ®_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(®_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; +} + +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); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_TIMER) + return kvm_riscv_vcpu_set_reg_timer(vcpu, reg); + 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); + + 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); + else if ((reg->id & KVM_REG_RISCV_TYPE_MASK) == KVM_REG_RISCV_TIMER) + return kvm_riscv_vcpu_get_reg_timer(vcpu, reg); + 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); + + return -EINVAL; +} + +long kvm_arch_vcpu_async_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + 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); + } + + return -ENOIOCTLCMD; +} + +long kvm_arch_vcpu_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + 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(®, argp, sizeof(reg))) + break; + + if (ioctl == KVM_SET_ONE_REG) + r = kvm_riscv_vcpu_set_reg(vcpu, ®); + else + r = kvm_riscv_vcpu_get_reg(vcpu, ®); + break; + } + default: + break; + } + + return r; +} + +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; +} + +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); +} + +int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + if (vcpu->arch.power_off) + mp_state->mp_state = KVM_MP_STATE_STOPPED; + else + mp_state->mp_state = KVM_MP_STATE_RUNNABLE; + + return 0; +} + +int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + 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; +} + +int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, + struct kvm_guest_debug *dbg) +{ + /* TODO; To be implemented later. */ + return -EINVAL; +} + +void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) +{ + 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); + + kvm_riscv_stage2_update_hgatp(vcpu); + + kvm_riscv_vcpu_timer_restore(vcpu); + + kvm_riscv_vcpu_host_fp_save(&vcpu->arch.host_context); + kvm_riscv_vcpu_guest_fp_restore(&vcpu->arch.guest_context, + vcpu->arch.isa); + + vcpu->cpu = cpu; +} + +void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + + vcpu->cpu = -1; + + kvm_riscv_vcpu_guest_fp_save(&vcpu->arch.guest_context, + vcpu->arch.isa); + kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context); + + csr_write(CSR_HGATP, 0); + + 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); +} + +static void kvm_riscv_check_vcpu_requests(struct kvm_vcpu *vcpu) +{ + struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); + + if (kvm_request_pending(vcpu)) { + if (kvm_check_request(KVM_REQ_SLEEP, vcpu)) { + rcuwait_wait_event(wait, + (!vcpu->arch.power_off) && (!vcpu->arch.pause), + TASK_INTERRUPTIBLE); + + 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); + + if (kvm_check_request(KVM_REQ_UPDATE_HGATP, vcpu)) + kvm_riscv_stage2_update_hgatp(vcpu); + + if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) + __kvm_riscv_hfence_gvma_all(); + } +} + +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); +} + +int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) +{ + int ret; + struct kvm_cpu_trap trap; + struct kvm_run *run = vcpu->run; + + /* Mark this VCPU ran at least once */ + vcpu->arch.ran_atleast_once = true; + + vcpu->arch.srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + + /* Process MMIO value returned from user-space */ + if (run->exit_reason == KVM_EXIT_MMIO) { + ret = kvm_riscv_vcpu_mmio_return(vcpu, vcpu->run); + if (ret) { + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx); + return ret; + } + } + + /* Process SBI value returned from user-space */ + if (run->exit_reason == KVM_EXIT_RISCV_SBI) { + ret = kvm_riscv_vcpu_sbi_return(vcpu, vcpu->run); + if (ret) { + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx); + return ret; + } + } + + if (run->immediate_exit) { + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx); + 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(); + + kvm_riscv_stage2_vmid_update(vcpu); + + kvm_riscv_check_vcpu_requests(vcpu); + + preempt_disable(); + + 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/virtual/kvm/vcpu-requests.rst + */ + vcpu->mode = IN_GUEST_MODE; + + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx); + smp_mb__after_srcu_read_unlock(); + + /* + * 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); + + if (ret <= 0 || + kvm_riscv_stage2_vmid_ver_changed(&vcpu->kvm->arch.vmid) || + kvm_request_pending(vcpu)) { + vcpu->mode = OUTSIDE_GUEST_MODE; + local_irq_enable(); + preempt_enable(); + vcpu->arch.srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + continue; + } + + guest_enter_irqoff(); + + __kvm_riscv_switch_to(&vcpu->arch); + + 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. + */ + trap.sepc = vcpu->arch.guest_context.sepc; + trap.scause = csr_read(CSR_SCAUSE); + trap.stval = csr_read(CSR_STVAL); + trap.htval = csr_read(CSR_HTVAL); + trap.htinst = csr_read(CSR_HTINST); + + /* Syncup interrupts state with HW */ + kvm_riscv_vcpu_sync_interrupts(vcpu); + + /* + * We may have taken a host interrupt in VS/VU-mode (i.e. + * while executing the guest). This interrupt is still + * pending, as we haven't serviced it yet! + * + * We're now back in HS-mode with interrupts disabled + * so enabling the interrupts now will have the effect + * of taking the interrupt again, in HS-mode this time. + */ + local_irq_enable(); + + /* + * We do local_irq_enable() before calling guest_exit() so + * that if a timer interrupt hits while running the guest + * we account that tick as being spent in the guest. We + * enable preemption after calling guest_exit() so that if + * we get preempted we make sure ticks after that is not + * counted as guest time. + */ + guest_exit(); + + preempt_enable(); + + vcpu->arch.srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + + ret = kvm_riscv_vcpu_exit(vcpu, run, &trap); + } + + kvm_sigset_deactivate(vcpu); + + vcpu_put(vcpu); + + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx); + + return ret; +} |