diff options
Diffstat (limited to 'arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c')
-rw-r--r-- | arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c b/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c new file mode 100644 index 000000000..bd1bab551 --- /dev/null +++ b/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c @@ -0,0 +1,87 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012-2015 - ARM Ltd + * Author: Marc Zyngier <marc.zyngier@arm.com> + */ + +#include <linux/compiler.h> +#include <linux/irqchip/arm-gic.h> +#include <linux/kvm_host.h> +#include <linux/swab.h> + +#include <asm/kvm_emulate.h> +#include <asm/kvm_hyp.h> +#include <asm/kvm_mmu.h> + +static bool __is_be(struct kvm_vcpu *vcpu) +{ + if (vcpu_mode_is_32bit(vcpu)) + return !!(read_sysreg_el2(SYS_SPSR) & PSR_AA32_E_BIT); + + return !!(read_sysreg(SCTLR_EL1) & SCTLR_ELx_EE); +} + +/* + * __vgic_v2_perform_cpuif_access -- perform a GICV access on behalf of the + * guest. + * + * @vcpu: the offending vcpu + * + * Returns: + * 1: GICV access successfully performed + * 0: Not a GICV access + * -1: Illegal GICV access successfully performed + */ +int __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu) +{ + struct kvm *kvm = kern_hyp_va(vcpu->kvm); + struct vgic_dist *vgic = &kvm->arch.vgic; + phys_addr_t fault_ipa; + void __iomem *addr; + int rd; + + /* Build the full address */ + fault_ipa = kvm_vcpu_get_fault_ipa(vcpu); + fault_ipa |= kvm_vcpu_get_hfar(vcpu) & GENMASK(11, 0); + + /* If not for GICV, move on */ + if (fault_ipa < vgic->vgic_cpu_base || + fault_ipa >= (vgic->vgic_cpu_base + KVM_VGIC_V2_CPU_SIZE)) + return 0; + + /* Reject anything but a 32bit access */ + if (kvm_vcpu_dabt_get_as(vcpu) != sizeof(u32)) { + __kvm_skip_instr(vcpu); + return -1; + } + + /* Not aligned? Don't bother */ + if (fault_ipa & 3) { + __kvm_skip_instr(vcpu); + return -1; + } + + rd = kvm_vcpu_dabt_get_rd(vcpu); + addr = hyp_symbol_addr(kvm_vgic_global_state)->vcpu_hyp_va; + addr += fault_ipa - vgic->vgic_cpu_base; + + if (kvm_vcpu_dabt_iswrite(vcpu)) { + u32 data = vcpu_get_reg(vcpu, rd); + if (__is_be(vcpu)) { + /* guest pre-swabbed data, undo this for writel() */ + data = __kvm_swab32(data); + } + writel_relaxed(data, addr); + } else { + u32 data = readl_relaxed(addr); + if (__is_be(vcpu)) { + /* guest expects swabbed data */ + data = __kvm_swab32(data); + } + vcpu_set_reg(vcpu, rd, data); + } + + __kvm_skip_instr(vcpu); + + return 1; +} |