diff options
Diffstat (limited to 'arch/riscv/kvm/tlb.c')
| -rw-r--r-- | arch/riscv/kvm/tlb.c | 405 |
1 files changed, 405 insertions, 0 deletions
diff --git a/arch/riscv/kvm/tlb.c b/arch/riscv/kvm/tlb.c new file mode 100644 index 000000000000..23c0e82b5103 --- /dev/null +++ b/arch/riscv/kvm/tlb.c @@ -0,0 +1,405 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2022 Ventana Micro Systems Inc. + */ + +#include <linux/bitmap.h> +#include <linux/cpumask.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/smp.h> +#include <linux/kvm_host.h> +#include <asm/cacheflush.h> +#include <asm/csr.h> +#include <asm/cpufeature.h> +#include <asm/insn-def.h> + +#define has_svinval() riscv_has_extension_unlikely(RISCV_ISA_EXT_SVINVAL) + +void kvm_riscv_local_hfence_gvma_vmid_gpa(unsigned long vmid, + gpa_t gpa, gpa_t gpsz, + unsigned long order) +{ + gpa_t pos; + + if (PTRS_PER_PTE < (gpsz >> order)) { + kvm_riscv_local_hfence_gvma_vmid_all(vmid); + return; + } + + if (has_svinval()) { + asm volatile (SFENCE_W_INVAL() ::: "memory"); + for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order)) + asm volatile (HINVAL_GVMA(%0, %1) + : : "r" (pos >> 2), "r" (vmid) : "memory"); + asm volatile (SFENCE_INVAL_IR() ::: "memory"); + } else { + for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order)) + asm volatile (HFENCE_GVMA(%0, %1) + : : "r" (pos >> 2), "r" (vmid) : "memory"); + } +} + +void kvm_riscv_local_hfence_gvma_vmid_all(unsigned long vmid) +{ + asm volatile(HFENCE_GVMA(zero, %0) : : "r" (vmid) : "memory"); +} + +void kvm_riscv_local_hfence_gvma_gpa(gpa_t gpa, gpa_t gpsz, + unsigned long order) +{ + gpa_t pos; + + if (PTRS_PER_PTE < (gpsz >> order)) { + kvm_riscv_local_hfence_gvma_all(); + return; + } + + if (has_svinval()) { + asm volatile (SFENCE_W_INVAL() ::: "memory"); + for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order)) + asm volatile(HINVAL_GVMA(%0, zero) + : : "r" (pos >> 2) : "memory"); + asm volatile (SFENCE_INVAL_IR() ::: "memory"); + } else { + for (pos = gpa; pos < (gpa + gpsz); pos += BIT(order)) + asm volatile(HFENCE_GVMA(%0, zero) + : : "r" (pos >> 2) : "memory"); + } +} + +void kvm_riscv_local_hfence_gvma_all(void) +{ + asm volatile(HFENCE_GVMA(zero, zero) : : : "memory"); +} + +void kvm_riscv_local_hfence_vvma_asid_gva(unsigned long vmid, + unsigned long asid, + unsigned long gva, + unsigned long gvsz, + unsigned long order) +{ + unsigned long pos, hgatp; + + if (PTRS_PER_PTE < (gvsz >> order)) { + kvm_riscv_local_hfence_vvma_asid_all(vmid, asid); + return; + } + + hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT); + + if (has_svinval()) { + asm volatile (SFENCE_W_INVAL() ::: "memory"); + for (pos = gva; pos < (gva + gvsz); pos += BIT(order)) + asm volatile(HINVAL_VVMA(%0, %1) + : : "r" (pos), "r" (asid) : "memory"); + asm volatile (SFENCE_INVAL_IR() ::: "memory"); + } else { + for (pos = gva; pos < (gva + gvsz); pos += BIT(order)) + asm volatile(HFENCE_VVMA(%0, %1) + : : "r" (pos), "r" (asid) : "memory"); + } + + csr_write(CSR_HGATP, hgatp); +} + +void kvm_riscv_local_hfence_vvma_asid_all(unsigned long vmid, + unsigned long asid) +{ + unsigned long hgatp; + + hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT); + + asm volatile(HFENCE_VVMA(zero, %0) : : "r" (asid) : "memory"); + + csr_write(CSR_HGATP, hgatp); +} + +void kvm_riscv_local_hfence_vvma_gva(unsigned long vmid, + unsigned long gva, unsigned long gvsz, + unsigned long order) +{ + unsigned long pos, hgatp; + + if (PTRS_PER_PTE < (gvsz >> order)) { + kvm_riscv_local_hfence_vvma_all(vmid); + return; + } + + hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT); + + if (has_svinval()) { + asm volatile (SFENCE_W_INVAL() ::: "memory"); + for (pos = gva; pos < (gva + gvsz); pos += BIT(order)) + asm volatile(HINVAL_VVMA(%0, zero) + : : "r" (pos) : "memory"); + asm volatile (SFENCE_INVAL_IR() ::: "memory"); + } else { + for (pos = gva; pos < (gva + gvsz); pos += BIT(order)) + asm volatile(HFENCE_VVMA(%0, zero) + : : "r" (pos) : "memory"); + } + + csr_write(CSR_HGATP, hgatp); +} + +void kvm_riscv_local_hfence_vvma_all(unsigned long vmid) +{ + unsigned long hgatp; + + hgatp = csr_swap(CSR_HGATP, vmid << HGATP_VMID_SHIFT); + + asm volatile(HFENCE_VVMA(zero, zero) : : : "memory"); + + csr_write(CSR_HGATP, hgatp); +} + +void kvm_riscv_local_tlb_sanitize(struct kvm_vcpu *vcpu) +{ + unsigned long vmid; + + if (!kvm_riscv_gstage_vmid_bits() || + vcpu->arch.last_exit_cpu == vcpu->cpu) + return; + + /* + * 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. + */ + + vmid = READ_ONCE(vcpu->kvm->arch.vmid.vmid); + kvm_riscv_local_hfence_gvma_vmid_all(vmid); +} + +void kvm_riscv_fence_i_process(struct kvm_vcpu *vcpu) +{ + kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_FENCE_I_RCVD); + local_flush_icache_all(); +} + +void kvm_riscv_hfence_gvma_vmid_all_process(struct kvm_vcpu *vcpu) +{ + struct kvm_vmid *vmid; + + vmid = &vcpu->kvm->arch.vmid; + kvm_riscv_local_hfence_gvma_vmid_all(READ_ONCE(vmid->vmid)); +} + +void kvm_riscv_hfence_vvma_all_process(struct kvm_vcpu *vcpu) +{ + struct kvm_vmid *vmid; + + vmid = &vcpu->kvm->arch.vmid; + kvm_riscv_local_hfence_vvma_all(READ_ONCE(vmid->vmid)); +} + +static bool vcpu_hfence_dequeue(struct kvm_vcpu *vcpu, + struct kvm_riscv_hfence *out_data) +{ + bool ret = false; + struct kvm_vcpu_arch *varch = &vcpu->arch; + + spin_lock(&varch->hfence_lock); + + if (varch->hfence_queue[varch->hfence_head].type) { + memcpy(out_data, &varch->hfence_queue[varch->hfence_head], + sizeof(*out_data)); + varch->hfence_queue[varch->hfence_head].type = 0; + + varch->hfence_head++; + if (varch->hfence_head == KVM_RISCV_VCPU_MAX_HFENCE) + varch->hfence_head = 0; + + ret = true; + } + + spin_unlock(&varch->hfence_lock); + + return ret; +} + +static bool vcpu_hfence_enqueue(struct kvm_vcpu *vcpu, + const struct kvm_riscv_hfence *data) +{ + bool ret = false; + struct kvm_vcpu_arch *varch = &vcpu->arch; + + spin_lock(&varch->hfence_lock); + + if (!varch->hfence_queue[varch->hfence_tail].type) { + memcpy(&varch->hfence_queue[varch->hfence_tail], + data, sizeof(*data)); + + varch->hfence_tail++; + if (varch->hfence_tail == KVM_RISCV_VCPU_MAX_HFENCE) + varch->hfence_tail = 0; + + ret = true; + } + + spin_unlock(&varch->hfence_lock); + + return ret; +} + +void kvm_riscv_hfence_process(struct kvm_vcpu *vcpu) +{ + struct kvm_riscv_hfence d = { 0 }; + struct kvm_vmid *v = &vcpu->kvm->arch.vmid; + + while (vcpu_hfence_dequeue(vcpu, &d)) { + switch (d.type) { + case KVM_RISCV_HFENCE_UNKNOWN: + break; + case KVM_RISCV_HFENCE_GVMA_VMID_GPA: + kvm_riscv_local_hfence_gvma_vmid_gpa( + READ_ONCE(v->vmid), + d.addr, d.size, d.order); + break; + case KVM_RISCV_HFENCE_VVMA_ASID_GVA: + kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_HFENCE_VVMA_ASID_RCVD); + kvm_riscv_local_hfence_vvma_asid_gva( + READ_ONCE(v->vmid), d.asid, + d.addr, d.size, d.order); + break; + case KVM_RISCV_HFENCE_VVMA_ASID_ALL: + kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_HFENCE_VVMA_ASID_RCVD); + kvm_riscv_local_hfence_vvma_asid_all( + READ_ONCE(v->vmid), d.asid); + break; + case KVM_RISCV_HFENCE_VVMA_GVA: + kvm_riscv_vcpu_pmu_incr_fw(vcpu, SBI_PMU_FW_HFENCE_VVMA_RCVD); + kvm_riscv_local_hfence_vvma_gva( + READ_ONCE(v->vmid), + d.addr, d.size, d.order); + break; + default: + break; + } + } +} + +static void make_xfence_request(struct kvm *kvm, + unsigned long hbase, unsigned long hmask, + unsigned int req, unsigned int fallback_req, + const struct kvm_riscv_hfence *data) +{ + unsigned long i; + struct kvm_vcpu *vcpu; + unsigned int actual_req = req; + DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS); + + bitmap_zero(vcpu_mask, KVM_MAX_VCPUS); + kvm_for_each_vcpu(i, vcpu, kvm) { + if (hbase != -1UL) { + if (vcpu->vcpu_id < hbase) + continue; + if (!(hmask & (1UL << (vcpu->vcpu_id - hbase)))) + continue; + } + + bitmap_set(vcpu_mask, i, 1); + + if (!data || !data->type) + continue; + + /* + * Enqueue hfence data to VCPU hfence queue. If we don't + * have space in the VCPU hfence queue then fallback to + * a more conservative hfence request. + */ + if (!vcpu_hfence_enqueue(vcpu, data)) + actual_req = fallback_req; + } + + kvm_make_vcpus_request_mask(kvm, actual_req, vcpu_mask); +} + +void kvm_riscv_fence_i(struct kvm *kvm, + unsigned long hbase, unsigned long hmask) +{ + make_xfence_request(kvm, hbase, hmask, KVM_REQ_FENCE_I, + KVM_REQ_FENCE_I, NULL); +} + +void kvm_riscv_hfence_gvma_vmid_gpa(struct kvm *kvm, + unsigned long hbase, unsigned long hmask, + gpa_t gpa, gpa_t gpsz, + unsigned long order) +{ + struct kvm_riscv_hfence data; + + data.type = KVM_RISCV_HFENCE_GVMA_VMID_GPA; + data.asid = 0; + data.addr = gpa; + data.size = gpsz; + data.order = order; + make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE, + KVM_REQ_HFENCE_GVMA_VMID_ALL, &data); +} + +void kvm_riscv_hfence_gvma_vmid_all(struct kvm *kvm, + unsigned long hbase, unsigned long hmask) +{ + make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE_GVMA_VMID_ALL, + KVM_REQ_HFENCE_GVMA_VMID_ALL, NULL); +} + +void kvm_riscv_hfence_vvma_asid_gva(struct kvm *kvm, + unsigned long hbase, unsigned long hmask, + unsigned long gva, unsigned long gvsz, + unsigned long order, unsigned long asid) +{ + struct kvm_riscv_hfence data; + + data.type = KVM_RISCV_HFENCE_VVMA_ASID_GVA; + data.asid = asid; + data.addr = gva; + data.size = gvsz; + data.order = order; + make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE, + KVM_REQ_HFENCE_VVMA_ALL, &data); +} + +void kvm_riscv_hfence_vvma_asid_all(struct kvm *kvm, + unsigned long hbase, unsigned long hmask, + unsigned long asid) +{ + struct kvm_riscv_hfence data; + + data.type = KVM_RISCV_HFENCE_VVMA_ASID_ALL; + data.asid = asid; + data.addr = data.size = data.order = 0; + make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE, + KVM_REQ_HFENCE_VVMA_ALL, &data); +} + +void kvm_riscv_hfence_vvma_gva(struct kvm *kvm, + unsigned long hbase, unsigned long hmask, + unsigned long gva, unsigned long gvsz, + unsigned long order) +{ + struct kvm_riscv_hfence data; + + data.type = KVM_RISCV_HFENCE_VVMA_GVA; + data.asid = 0; + data.addr = gva; + data.size = gvsz; + data.order = order; + make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE, + KVM_REQ_HFENCE_VVMA_ALL, &data); +} + +void kvm_riscv_hfence_vvma_all(struct kvm *kvm, + unsigned long hbase, unsigned long hmask) +{ + make_xfence_request(kvm, hbase, hmask, KVM_REQ_HFENCE_VVMA_ALL, + KVM_REQ_HFENCE_VVMA_ALL, NULL); +} |