1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2022 SiFive 4 * 5 * Authors: 6 * Vincent Chen <vincent.chen@sifive.com> 7 * Greentime Hu <greentime.hu@sifive.com> 8 */ 9 10 #include <linux/errno.h> 11 #include <linux/err.h> 12 #include <linux/kvm_host.h> 13 #include <linux/uaccess.h> 14 #include <asm/cpufeature.h> 15 #include <asm/kvm_vcpu_vector.h> 16 #include <asm/vector.h> 17 18 #ifdef CONFIG_RISCV_ISA_V 19 void kvm_riscv_vcpu_vector_reset(struct kvm_vcpu *vcpu) 20 { 21 unsigned long *isa = vcpu->arch.isa; 22 struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; 23 24 cntx->sstatus &= ~SR_VS; 25 if (riscv_isa_extension_available(isa, v)) { 26 cntx->sstatus |= SR_VS_INITIAL; 27 WARN_ON(!cntx->vector.datap); 28 memset(cntx->vector.datap, 0, riscv_v_vsize); 29 } else { 30 cntx->sstatus |= SR_VS_OFF; 31 } 32 } 33 34 static void kvm_riscv_vcpu_vector_clean(struct kvm_cpu_context *cntx) 35 { 36 cntx->sstatus &= ~SR_VS; 37 cntx->sstatus |= SR_VS_CLEAN; 38 } 39 40 void kvm_riscv_vcpu_guest_vector_save(struct kvm_cpu_context *cntx, 41 unsigned long *isa) 42 { 43 if ((cntx->sstatus & SR_VS) == SR_VS_DIRTY) { 44 if (riscv_isa_extension_available(isa, v)) 45 __kvm_riscv_vector_save(cntx); 46 kvm_riscv_vcpu_vector_clean(cntx); 47 } 48 } 49 50 void kvm_riscv_vcpu_guest_vector_restore(struct kvm_cpu_context *cntx, 51 unsigned long *isa) 52 { 53 if ((cntx->sstatus & SR_VS) != SR_VS_OFF) { 54 if (riscv_isa_extension_available(isa, v)) 55 __kvm_riscv_vector_restore(cntx); 56 kvm_riscv_vcpu_vector_clean(cntx); 57 } 58 } 59 60 void kvm_riscv_vcpu_host_vector_save(struct kvm_cpu_context *cntx) 61 { 62 /* No need to check host sstatus as it can be modified outside */ 63 if (riscv_isa_extension_available(NULL, v)) 64 __kvm_riscv_vector_save(cntx); 65 } 66 67 void kvm_riscv_vcpu_host_vector_restore(struct kvm_cpu_context *cntx) 68 { 69 if (riscv_isa_extension_available(NULL, v)) 70 __kvm_riscv_vector_restore(cntx); 71 } 72 73 int kvm_riscv_vcpu_alloc_vector_context(struct kvm_vcpu *vcpu, 74 struct kvm_cpu_context *cntx) 75 { 76 cntx->vector.datap = kmalloc(riscv_v_vsize, GFP_KERNEL); 77 if (!cntx->vector.datap) 78 return -ENOMEM; 79 80 vcpu->arch.host_context.vector.datap = kzalloc(riscv_v_vsize, GFP_KERNEL); 81 if (!vcpu->arch.host_context.vector.datap) 82 return -ENOMEM; 83 84 return 0; 85 } 86 87 void kvm_riscv_vcpu_free_vector_context(struct kvm_vcpu *vcpu) 88 { 89 kfree(vcpu->arch.guest_reset_context.vector.datap); 90 kfree(vcpu->arch.host_context.vector.datap); 91 } 92 #endif 93 94 static int kvm_riscv_vcpu_vreg_addr(struct kvm_vcpu *vcpu, 95 unsigned long reg_num, 96 size_t reg_size, 97 void **reg_addr) 98 { 99 struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; 100 size_t vlenb = riscv_v_vsize / 32; 101 102 if (reg_num < KVM_REG_RISCV_VECTOR_REG(0)) { 103 if (reg_size != sizeof(unsigned long)) 104 return -EINVAL; 105 switch (reg_num) { 106 case KVM_REG_RISCV_VECTOR_CSR_REG(vstart): 107 *reg_addr = &cntx->vector.vstart; 108 break; 109 case KVM_REG_RISCV_VECTOR_CSR_REG(vl): 110 *reg_addr = &cntx->vector.vl; 111 break; 112 case KVM_REG_RISCV_VECTOR_CSR_REG(vtype): 113 *reg_addr = &cntx->vector.vtype; 114 break; 115 case KVM_REG_RISCV_VECTOR_CSR_REG(vcsr): 116 *reg_addr = &cntx->vector.vcsr; 117 break; 118 case KVM_REG_RISCV_VECTOR_CSR_REG(datap): 119 default: 120 return -ENOENT; 121 } 122 } else if (reg_num <= KVM_REG_RISCV_VECTOR_REG(31)) { 123 if (reg_size != vlenb) 124 return -EINVAL; 125 *reg_addr = cntx->vector.datap + 126 (reg_num - KVM_REG_RISCV_VECTOR_REG(0)) * vlenb; 127 } else { 128 return -ENOENT; 129 } 130 131 return 0; 132 } 133 134 int kvm_riscv_vcpu_get_reg_vector(struct kvm_vcpu *vcpu, 135 const struct kvm_one_reg *reg) 136 { 137 unsigned long *isa = vcpu->arch.isa; 138 unsigned long __user *uaddr = 139 (unsigned long __user *)(unsigned long)reg->addr; 140 unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | 141 KVM_REG_SIZE_MASK | 142 KVM_REG_RISCV_VECTOR); 143 size_t reg_size = KVM_REG_SIZE(reg->id); 144 void *reg_addr; 145 int rc; 146 147 if (!riscv_isa_extension_available(isa, v)) 148 return -ENOENT; 149 150 rc = kvm_riscv_vcpu_vreg_addr(vcpu, reg_num, reg_size, ®_addr); 151 if (rc) 152 return rc; 153 154 if (copy_to_user(uaddr, reg_addr, reg_size)) 155 return -EFAULT; 156 157 return 0; 158 } 159 160 int kvm_riscv_vcpu_set_reg_vector(struct kvm_vcpu *vcpu, 161 const struct kvm_one_reg *reg) 162 { 163 unsigned long *isa = vcpu->arch.isa; 164 unsigned long __user *uaddr = 165 (unsigned long __user *)(unsigned long)reg->addr; 166 unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | 167 KVM_REG_SIZE_MASK | 168 KVM_REG_RISCV_VECTOR); 169 size_t reg_size = KVM_REG_SIZE(reg->id); 170 void *reg_addr; 171 int rc; 172 173 if (!riscv_isa_extension_available(isa, v)) 174 return -ENOENT; 175 176 rc = kvm_riscv_vcpu_vreg_addr(vcpu, reg_num, reg_size, ®_addr); 177 if (rc) 178 return rc; 179 180 if (copy_from_user(reg_addr, uaddr, reg_size)) 181 return -EFAULT; 182 183 return 0; 184 } 185