diff options
Diffstat (limited to 'arch/riscv/kvm/vcpu.c')
| -rw-r--r-- | arch/riscv/kvm/vcpu.c | 1018 |
1 files changed, 1018 insertions, 0 deletions
diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c new file mode 100644 index 000000000000..a55a95da54d0 --- /dev/null +++ b/arch/riscv/kvm/vcpu.c @@ -0,0 +1,1018 @@ +// 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/vmalloc.h> +#include <linux/sched/signal.h> +#include <linux/fs.h> +#include <linux/kvm_host.h> +#include <asm/cacheflush.h> +#include <asm/kvm_mmu.h> +#include <asm/kvm_nacl.h> +#include <asm/kvm_vcpu_vector.h> + +#define CREATE_TRACE_POINTS +#include "trace.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, wrs_exit_stat), + STATS_DESC_COUNTER(VCPU, mmio_exit_user), + STATS_DESC_COUNTER(VCPU, mmio_exit_kernel), + STATS_DESC_COUNTER(VCPU, csr_exit_user), + STATS_DESC_COUNTER(VCPU, csr_exit_kernel), + STATS_DESC_COUNTER(VCPU, signal_exits), + STATS_DESC_COUNTER(VCPU, exits), + STATS_DESC_COUNTER(VCPU, instr_illegal_exits), + STATS_DESC_COUNTER(VCPU, load_misaligned_exits), + STATS_DESC_COUNTER(VCPU, store_misaligned_exits), + STATS_DESC_COUNTER(VCPU, load_access_exits), + STATS_DESC_COUNTER(VCPU, store_access_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), +}; + +static void kvm_riscv_vcpu_context_reset(struct kvm_vcpu *vcpu, + bool kvm_sbi_reset) +{ + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; + void *vector_datap = cntx->vector.datap; + + memset(cntx, 0, sizeof(*cntx)); + memset(csr, 0, sizeof(*csr)); + memset(&vcpu->arch.smstateen_csr, 0, sizeof(vcpu->arch.smstateen_csr)); + + /* Restore datap as it's not a part of the guest context. */ + cntx->vector.datap = vector_datap; + + if (kvm_sbi_reset) + kvm_riscv_vcpu_sbi_load_reset_state(vcpu); + + /* Setup reset state of shadow SSTATUS and HSTATUS CSRs */ + cntx->sstatus = SR_SPP | SR_SPIE; + + cntx->hstatus |= HSTATUS_VTW; + cntx->hstatus |= HSTATUS_SPVP; + cntx->hstatus |= HSTATUS_SPV; +} + +static void kvm_riscv_reset_vcpu(struct kvm_vcpu *vcpu, bool kvm_sbi_reset) +{ + 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); + + vcpu->arch.last_exit_cpu = -1; + + kvm_riscv_vcpu_context_reset(vcpu, kvm_sbi_reset); + + kvm_riscv_vcpu_fp_reset(vcpu); + + kvm_riscv_vcpu_vector_reset(vcpu); + + kvm_riscv_vcpu_timer_reset(vcpu); + + kvm_riscv_vcpu_aia_reset(vcpu); + + bitmap_zero(vcpu->arch.irqs_pending, KVM_RISCV_VCPU_NR_IRQS); + bitmap_zero(vcpu->arch.irqs_pending_mask, KVM_RISCV_VCPU_NR_IRQS); + + kvm_riscv_vcpu_pmu_reset(vcpu); + + vcpu->arch.hfence_head = 0; + vcpu->arch.hfence_tail = 0; + memset(vcpu->arch.hfence_queue, 0, sizeof(vcpu->arch.hfence_queue)); + + kvm_riscv_vcpu_sbi_reset(vcpu); + + /* Reset the guest CSRs for hotplug usecase */ + if (loaded) + kvm_arch_vcpu_load(vcpu, smp_processor_id()); + put_cpu(); +} + +int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id) +{ + return 0; +} + +int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) +{ + int rc; + + spin_lock_init(&vcpu->arch.mp_state_lock); + + /* Mark this VCPU never ran */ + vcpu->arch.ran_atleast_once = false; + + vcpu->arch.cfg.hedeleg = KVM_HEDELEG_DEFAULT; + vcpu->arch.mmu_page_cache.gfp_zero = __GFP_ZERO; + bitmap_zero(vcpu->arch.isa, RISCV_ISA_EXT_MAX); + + /* Setup ISA features available to VCPU */ + kvm_riscv_vcpu_setup_isa(vcpu); + + /* Setup vendor, arch, and implementation details */ + vcpu->arch.mvendorid = sbi_get_mvendorid(); + vcpu->arch.marchid = sbi_get_marchid(); + vcpu->arch.mimpid = sbi_get_mimpid(); + + /* Setup VCPU hfence queue */ + spin_lock_init(&vcpu->arch.hfence_lock); + + spin_lock_init(&vcpu->arch.reset_state.lock); + + rc = kvm_riscv_vcpu_alloc_vector_context(vcpu); + if (rc) + return rc; + + /* Setup VCPU timer */ + kvm_riscv_vcpu_timer_init(vcpu); + + /* setup performance monitoring */ + kvm_riscv_vcpu_pmu_init(vcpu); + + /* Setup VCPU AIA */ + kvm_riscv_vcpu_aia_init(vcpu); + + /* + * Setup SBI extensions + * NOTE: This must be the last thing to be initialized. + */ + kvm_riscv_vcpu_sbi_init(vcpu); + + /* Reset VCPU */ + kvm_riscv_reset_vcpu(vcpu, false); + + return 0; +} + +void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) +{ + /** + * 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); +} + +void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) +{ + kvm_riscv_vcpu_sbi_deinit(vcpu); + + /* Cleanup VCPU AIA context */ + kvm_riscv_vcpu_aia_deinit(vcpu); + + /* Cleanup VCPU timer */ + kvm_riscv_vcpu_timer_deinit(vcpu); + + kvm_riscv_vcpu_pmu_deinit(vcpu); + + /* Free unused pages pre-allocated for G-stage page table mappings */ + kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); + + /* Free vector context space for host and guest kernel */ + kvm_riscv_vcpu_free_vector_context(vcpu); +} + +int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) +{ + return kvm_riscv_vcpu_timer_pending(vcpu); +} + +int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu) +{ + return (kvm_riscv_vcpu_has_interrupts(vcpu, -1ULL) && + !kvm_riscv_vcpu_stopped(vcpu) && !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; +} + +#ifdef CONFIG_GUEST_PERF_EVENTS +unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.guest_context.sepc; +} +#endif + +vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) +{ + return VM_FAULT_SIGBUS; +} + +long kvm_arch_vcpu_unlocked_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; + } + case KVM_GET_REG_LIST: { + struct kvm_reg_list __user *user_list = argp; + struct kvm_reg_list reg_list; + unsigned int n; + + r = -EFAULT; + if (copy_from_user(®_list, user_list, sizeof(reg_list))) + break; + n = reg_list.n; + reg_list.n = kvm_riscv_vcpu_num_regs(vcpu); + if (copy_to_user(user_list, ®_list, sizeof(reg_list))) + break; + r = -E2BIG; + if (n < reg_list.n) + break; + r = kvm_riscv_vcpu_copy_reg_indices(vcpu, user_list->reg); + 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[0])) { + mask = xchg_acquire(&vcpu->arch.irqs_pending_mask[0], 0); + val = READ_ONCE(vcpu->arch.irqs_pending[0]) & mask; + + csr->hvip &= ~mask; + csr->hvip |= val; + } + + /* Flush AIA high interrupts */ + kvm_riscv_vcpu_aia_flush_interrupts(vcpu); +} + +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 = ncsr_read(CSR_VSIE); + + /* Sync-up HVIP.VSSIP bit changes does by Guest */ + hvip = ncsr_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); + } + } + + /* Sync up the HVIP.LCOFIP bit changes (only clear) by the guest */ + if ((csr->hvip ^ hvip) & (1UL << IRQ_PMU_OVF)) { + if (!(hvip & (1UL << IRQ_PMU_OVF)) && + !test_and_set_bit(IRQ_PMU_OVF, v->irqs_pending_mask)) + clear_bit(IRQ_PMU_OVF, v->irqs_pending); + } + + /* Sync-up AIA high interrupts */ + kvm_riscv_vcpu_aia_sync_interrupts(vcpu); + + /* Sync-up timer CSRs */ + kvm_riscv_vcpu_timer_sync(vcpu); +} + +int kvm_riscv_vcpu_set_interrupt(struct kvm_vcpu *vcpu, unsigned int irq) +{ + /* + * We only allow VS-mode software, timer, and external + * interrupts when irq is one of the local interrupts + * defined by RISC-V privilege specification. + */ + if (irq < IRQ_LOCAL_MAX && + irq != IRQ_VS_SOFT && + irq != IRQ_VS_TIMER && + irq != IRQ_VS_EXT && + irq != IRQ_PMU_OVF) + 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) +{ + /* + * We only allow VS-mode software, timer, counter overflow and external + * interrupts when irq is one of the local interrupts + * defined by RISC-V privilege specification. + */ + if (irq < IRQ_LOCAL_MAX && + irq != IRQ_VS_SOFT && + irq != IRQ_VS_TIMER && + irq != IRQ_VS_EXT && + irq != IRQ_PMU_OVF) + 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, u64 mask) +{ + unsigned long ie; + + ie = ((vcpu->arch.guest_csr.vsie & VSIP_VALID_MASK) + << VSIP_TO_HVIP_SHIFT) & (unsigned long)mask; + ie |= vcpu->arch.guest_csr.vsie & ~IRQ_LOCAL_MASK & + (unsigned long)mask; + if (READ_ONCE(vcpu->arch.irqs_pending[0]) & ie) + return true; + + /* Check AIA high interrupts */ + return kvm_riscv_vcpu_aia_has_interrupts(vcpu, mask); +} + +void __kvm_riscv_vcpu_power_off(struct kvm_vcpu *vcpu) +{ + WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_STOPPED); + kvm_make_request(KVM_REQ_SLEEP, vcpu); + kvm_vcpu_kick(vcpu); +} + +void kvm_riscv_vcpu_power_off(struct kvm_vcpu *vcpu) +{ + spin_lock(&vcpu->arch.mp_state_lock); + __kvm_riscv_vcpu_power_off(vcpu); + spin_unlock(&vcpu->arch.mp_state_lock); +} + +void __kvm_riscv_vcpu_power_on(struct kvm_vcpu *vcpu) +{ + WRITE_ONCE(vcpu->arch.mp_state.mp_state, KVM_MP_STATE_RUNNABLE); + kvm_vcpu_wake_up(vcpu); +} + +void kvm_riscv_vcpu_power_on(struct kvm_vcpu *vcpu) +{ + spin_lock(&vcpu->arch.mp_state_lock); + __kvm_riscv_vcpu_power_on(vcpu); + spin_unlock(&vcpu->arch.mp_state_lock); +} + +bool kvm_riscv_vcpu_stopped(struct kvm_vcpu *vcpu) +{ + return READ_ONCE(vcpu->arch.mp_state.mp_state) == KVM_MP_STATE_STOPPED; +} + +int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + *mp_state = READ_ONCE(vcpu->arch.mp_state); + + return 0; +} + +int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + int ret = 0; + + spin_lock(&vcpu->arch.mp_state_lock); + + switch (mp_state->mp_state) { + case KVM_MP_STATE_RUNNABLE: + WRITE_ONCE(vcpu->arch.mp_state, *mp_state); + break; + case KVM_MP_STATE_STOPPED: + __kvm_riscv_vcpu_power_off(vcpu); + break; + case KVM_MP_STATE_INIT_RECEIVED: + if (vcpu->kvm->arch.mp_state_reset) + kvm_riscv_reset_vcpu(vcpu, false); + else + ret = -EINVAL; + break; + default: + ret = -EINVAL; + } + + spin_unlock(&vcpu->arch.mp_state_lock); + + return ret; +} + +int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, + struct kvm_guest_debug *dbg) +{ + if (dbg->control & KVM_GUESTDBG_ENABLE) { + vcpu->guest_debug = dbg->control; + vcpu->arch.cfg.hedeleg &= ~BIT(EXC_BREAKPOINT); + } else { + vcpu->guest_debug = 0; + vcpu->arch.cfg.hedeleg |= BIT(EXC_BREAKPOINT); + } + + return 0; +} + +static void kvm_riscv_vcpu_setup_config(struct kvm_vcpu *vcpu) +{ + const unsigned long *isa = vcpu->arch.isa; + struct kvm_vcpu_config *cfg = &vcpu->arch.cfg; + + if (riscv_isa_extension_available(isa, SVPBMT)) + cfg->henvcfg |= ENVCFG_PBMTE; + + if (riscv_isa_extension_available(isa, SSTC)) + cfg->henvcfg |= ENVCFG_STCE; + + if (riscv_isa_extension_available(isa, ZICBOM)) + cfg->henvcfg |= (ENVCFG_CBIE | ENVCFG_CBCFE); + + if (riscv_isa_extension_available(isa, ZICBOZ)) + cfg->henvcfg |= ENVCFG_CBZE; + + if (riscv_isa_extension_available(isa, SVADU) && + !riscv_isa_extension_available(isa, SVADE)) + cfg->henvcfg |= ENVCFG_ADUE; + + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN)) { + cfg->hstateen0 |= SMSTATEEN0_HSENVCFG; + if (riscv_isa_extension_available(isa, SSAIA)) + cfg->hstateen0 |= SMSTATEEN0_AIA_IMSIC | + SMSTATEEN0_AIA | + SMSTATEEN0_AIA_ISEL; + if (riscv_isa_extension_available(isa, SMSTATEEN)) + cfg->hstateen0 |= SMSTATEEN0_SSTATEEN0; + } + + if (vcpu->guest_debug) + cfg->hedeleg &= ~BIT(EXC_BREAKPOINT); +} + +void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) +{ + void *nsh; + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + struct kvm_vcpu_config *cfg = &vcpu->arch.cfg; + + if (kvm_riscv_nacl_sync_csr_available()) { + nsh = nacl_shmem(); + nacl_csr_write(nsh, CSR_VSSTATUS, csr->vsstatus); + nacl_csr_write(nsh, CSR_VSIE, csr->vsie); + nacl_csr_write(nsh, CSR_VSTVEC, csr->vstvec); + nacl_csr_write(nsh, CSR_VSSCRATCH, csr->vsscratch); + nacl_csr_write(nsh, CSR_VSEPC, csr->vsepc); + nacl_csr_write(nsh, CSR_VSCAUSE, csr->vscause); + nacl_csr_write(nsh, CSR_VSTVAL, csr->vstval); + nacl_csr_write(nsh, CSR_HEDELEG, cfg->hedeleg); + nacl_csr_write(nsh, CSR_HVIP, csr->hvip); + nacl_csr_write(nsh, CSR_VSATP, csr->vsatp); + nacl_csr_write(nsh, CSR_HENVCFG, cfg->henvcfg); + if (IS_ENABLED(CONFIG_32BIT)) + nacl_csr_write(nsh, CSR_HENVCFGH, cfg->henvcfg >> 32); + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN)) { + nacl_csr_write(nsh, CSR_HSTATEEN0, cfg->hstateen0); + if (IS_ENABLED(CONFIG_32BIT)) + nacl_csr_write(nsh, CSR_HSTATEEN0H, cfg->hstateen0 >> 32); + } + } else { + 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_HEDELEG, cfg->hedeleg); + csr_write(CSR_HVIP, csr->hvip); + csr_write(CSR_VSATP, csr->vsatp); + csr_write(CSR_HENVCFG, cfg->henvcfg); + if (IS_ENABLED(CONFIG_32BIT)) + csr_write(CSR_HENVCFGH, cfg->henvcfg >> 32); + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN)) { + csr_write(CSR_HSTATEEN0, cfg->hstateen0); + if (IS_ENABLED(CONFIG_32BIT)) + csr_write(CSR_HSTATEEN0H, cfg->hstateen0 >> 32); + } + } + + kvm_riscv_mmu_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); + kvm_riscv_vcpu_host_vector_save(&vcpu->arch.host_context); + kvm_riscv_vcpu_guest_vector_restore(&vcpu->arch.guest_context, + vcpu->arch.isa); + + kvm_riscv_vcpu_aia_load(vcpu, cpu); + + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); + + vcpu->cpu = cpu; +} + +void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) +{ + void *nsh; + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + + vcpu->cpu = -1; + + kvm_riscv_vcpu_aia_put(vcpu); + + kvm_riscv_vcpu_guest_fp_save(&vcpu->arch.guest_context, + vcpu->arch.isa); + kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context); + + kvm_riscv_vcpu_timer_save(vcpu); + kvm_riscv_vcpu_guest_vector_save(&vcpu->arch.guest_context, + vcpu->arch.isa); + kvm_riscv_vcpu_host_vector_restore(&vcpu->arch.host_context); + + if (kvm_riscv_nacl_available()) { + nsh = nacl_shmem(); + csr->vsstatus = nacl_csr_read(nsh, CSR_VSSTATUS); + csr->vsie = nacl_csr_read(nsh, CSR_VSIE); + csr->vstvec = nacl_csr_read(nsh, CSR_VSTVEC); + csr->vsscratch = nacl_csr_read(nsh, CSR_VSSCRATCH); + csr->vsepc = nacl_csr_read(nsh, CSR_VSEPC); + csr->vscause = nacl_csr_read(nsh, CSR_VSCAUSE); + csr->vstval = nacl_csr_read(nsh, CSR_VSTVAL); + csr->hvip = nacl_csr_read(nsh, CSR_HVIP); + csr->vsatp = nacl_csr_read(nsh, CSR_VSATP); + } else { + 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); + } +} + +/** + * kvm_riscv_check_vcpu_requests - check and handle pending vCPU requests + * @vcpu: the VCPU pointer + * + * Return: 1 if we should enter the guest + * 0 if we should exit to userspace + */ +static int 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)) { + kvm_vcpu_srcu_read_unlock(vcpu); + rcuwait_wait_event(wait, + (!kvm_riscv_vcpu_stopped(vcpu)) && (!vcpu->arch.pause), + TASK_INTERRUPTIBLE); + kvm_vcpu_srcu_read_lock(vcpu); + + if (kvm_riscv_vcpu_stopped(vcpu) || 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, true); + + if (kvm_check_request(KVM_REQ_UPDATE_HGATP, vcpu)) + kvm_riscv_mmu_update_hgatp(vcpu); + + if (kvm_check_request(KVM_REQ_FENCE_I, vcpu)) + kvm_riscv_fence_i_process(vcpu); + + if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) + kvm_riscv_tlb_flush_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); + + if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu)) + kvm_riscv_vcpu_record_steal_time(vcpu); + + if (kvm_dirty_ring_check_request(vcpu)) + return 0; + } + + return 1; +} + +static void kvm_riscv_update_hvip(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + + ncsr_write(CSR_HVIP, csr->hvip); + kvm_riscv_vcpu_aia_update_hvip(vcpu); +} + +static __always_inline void kvm_riscv_vcpu_swap_in_guest_state(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_smstateen_csr *smcsr = &vcpu->arch.smstateen_csr; + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + struct kvm_vcpu_config *cfg = &vcpu->arch.cfg; + + vcpu->arch.host_scounteren = csr_swap(CSR_SCOUNTEREN, csr->scounteren); + vcpu->arch.host_senvcfg = csr_swap(CSR_SENVCFG, csr->senvcfg); + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN) && + (cfg->hstateen0 & SMSTATEEN0_SSTATEEN0)) + vcpu->arch.host_sstateen0 = csr_swap(CSR_SSTATEEN0, + smcsr->sstateen0); +} + +static __always_inline void kvm_riscv_vcpu_swap_in_host_state(struct kvm_vcpu *vcpu) +{ + struct kvm_vcpu_smstateen_csr *smcsr = &vcpu->arch.smstateen_csr; + struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; + struct kvm_vcpu_config *cfg = &vcpu->arch.cfg; + + csr->scounteren = csr_swap(CSR_SCOUNTEREN, vcpu->arch.host_scounteren); + csr->senvcfg = csr_swap(CSR_SENVCFG, vcpu->arch.host_senvcfg); + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN) && + (cfg->hstateen0 & SMSTATEEN0_SSTATEEN0)) + smcsr->sstateen0 = csr_swap(CSR_SSTATEEN0, + vcpu->arch.host_sstateen0); +} + +/* + * 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, + struct kvm_cpu_trap *trap) +{ + void *nsh; + struct kvm_cpu_context *gcntx = &vcpu->arch.guest_context; + struct kvm_cpu_context *hcntx = &vcpu->arch.host_context; + + /* + * We save trap CSRs (such as SEPC, SCAUSE, STVAL, HTVAL, and + * HTINST) here because we do local_irq_enable() after this + * function in kvm_arch_vcpu_ioctl_run() which can result in + * an interrupt immediately after local_irq_enable() and can + * potentially change trap CSRs. + */ + + kvm_riscv_vcpu_swap_in_guest_state(vcpu); + guest_state_enter_irqoff(); + + if (kvm_riscv_nacl_sync_sret_available()) { + nsh = nacl_shmem(); + + if (kvm_riscv_nacl_autoswap_csr_available()) { + hcntx->hstatus = + nacl_csr_read(nsh, CSR_HSTATUS); + nacl_scratch_write_long(nsh, + SBI_NACL_SHMEM_AUTOSWAP_OFFSET + + SBI_NACL_SHMEM_AUTOSWAP_HSTATUS, + gcntx->hstatus); + nacl_scratch_write_long(nsh, + SBI_NACL_SHMEM_AUTOSWAP_OFFSET, + SBI_NACL_SHMEM_AUTOSWAP_FLAG_HSTATUS); + } else if (kvm_riscv_nacl_sync_csr_available()) { + hcntx->hstatus = nacl_csr_swap(nsh, + CSR_HSTATUS, gcntx->hstatus); + } else { + hcntx->hstatus = csr_swap(CSR_HSTATUS, gcntx->hstatus); + } + + nacl_scratch_write_longs(nsh, + SBI_NACL_SHMEM_SRET_OFFSET + + SBI_NACL_SHMEM_SRET_X(1), + &gcntx->ra, + SBI_NACL_SHMEM_SRET_X_LAST); + + __kvm_riscv_nacl_switch_to(&vcpu->arch, SBI_EXT_NACL, + SBI_EXT_NACL_SYNC_SRET); + + if (kvm_riscv_nacl_autoswap_csr_available()) { + nacl_scratch_write_long(nsh, + SBI_NACL_SHMEM_AUTOSWAP_OFFSET, + 0); + gcntx->hstatus = nacl_scratch_read_long(nsh, + SBI_NACL_SHMEM_AUTOSWAP_OFFSET + + SBI_NACL_SHMEM_AUTOSWAP_HSTATUS); + } else { + gcntx->hstatus = csr_swap(CSR_HSTATUS, hcntx->hstatus); + } + + trap->htval = nacl_csr_read(nsh, CSR_HTVAL); + trap->htinst = nacl_csr_read(nsh, CSR_HTINST); + } else { + hcntx->hstatus = csr_swap(CSR_HSTATUS, gcntx->hstatus); + + __kvm_riscv_switch_to(&vcpu->arch); + + gcntx->hstatus = csr_swap(CSR_HSTATUS, hcntx->hstatus); + + trap->htval = csr_read(CSR_HTVAL); + trap->htinst = csr_read(CSR_HTINST); + } + + trap->sepc = gcntx->sepc; + trap->scause = csr_read(CSR_SCAUSE); + trap->stval = csr_read(CSR_STVAL); + + vcpu->arch.last_exit_cpu = vcpu->cpu; + guest_state_exit_irqoff(); + kvm_riscv_vcpu_swap_in_host_state(vcpu); +} + +int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu) +{ + int ret; + struct kvm_cpu_trap trap; + struct kvm_run *run = vcpu->run; + + if (!vcpu->arch.ran_atleast_once) + kvm_riscv_vcpu_setup_config(vcpu); + + /* Mark this VCPU ran at least once */ + vcpu->arch.ran_atleast_once = true; + + kvm_vcpu_srcu_read_lock(vcpu); + + switch (run->exit_reason) { + case KVM_EXIT_MMIO: + /* Process MMIO value returned from user-space */ + ret = kvm_riscv_vcpu_mmio_return(vcpu, vcpu->run); + break; + case KVM_EXIT_RISCV_SBI: + /* Process SBI value returned from user-space */ + ret = kvm_riscv_vcpu_sbi_return(vcpu, vcpu->run); + 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; + } + + if (!vcpu->wants_to_run) { + kvm_vcpu_srcu_read_unlock(vcpu); + 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 */ + ret = kvm_xfer_to_guest_mode_handle_work(vcpu); + if (ret) + continue; + ret = 1; + + kvm_riscv_gstage_vmid_update(vcpu); + + ret = kvm_riscv_check_vcpu_requests(vcpu); + if (ret <= 0) + continue; + + preempt_disable(); + + /* Update AIA HW state before entering guest */ + ret = kvm_riscv_vcpu_aia_update(vcpu); + if (ret <= 0) { + preempt_enable(); + continue; + } + + local_irq_disable(); + + /* + * 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/virt/kvm/vcpu-requests.rst + */ + vcpu->mode = IN_GUEST_MODE; + + kvm_vcpu_srcu_read_unlock(vcpu); + 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 (kvm_riscv_gstage_vmid_ver_changed(&vcpu->kvm->arch.vmid) || + kvm_request_pending(vcpu) || + xfer_to_guest_mode_work_pending()) { + vcpu->mode = OUTSIDE_GUEST_MODE; + local_irq_enable(); + preempt_enable(); + kvm_vcpu_srcu_read_lock(vcpu); + continue; + } + + /* + * Sanitize VMID mappings cached (TLB) on current CPU + * + * 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); + + trace_kvm_entry(vcpu); + + guest_timing_enter_irqoff(); + + kvm_riscv_vcpu_enter_exit(vcpu, &trap); + + vcpu->mode = OUTSIDE_GUEST_MODE; + vcpu->stat.exits++; + + /* Syncup interrupts state with HW */ + kvm_riscv_vcpu_sync_interrupts(vcpu); + + /* + * 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. + * + * 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. + */ + local_irq_enable(); + local_irq_disable(); + + guest_timing_exit_irqoff(); + + local_irq_enable(); + + trace_kvm_exit(&trap); + + preempt_enable(); + + kvm_vcpu_srcu_read_lock(vcpu); + + ret = kvm_riscv_vcpu_exit(vcpu, run, &trap); + } + + kvm_sigset_deactivate(vcpu); + + vcpu_put(vcpu); + + kvm_vcpu_srcu_read_unlock(vcpu); + + return ret; +} |