1 // Copyright © 2019 Intel Corporation 2 // 3 // SPDX-License-Identifier: Apache-2.0 OR BSD-3-Clause 4 // 5 // Copyright © 2020, Microsoft Corporation 6 // 7 // Copyright 2018-2019 CrowdStrike, Inc. 8 // 9 // 10 11 pub mod gic; 12 13 use kvm_bindings::{ 14 kvm_mp_state, kvm_one_reg, kvm_regs, KVM_REG_ARM_COPROC_MASK, KVM_REG_ARM_CORE, 15 KVM_REG_SIZE_MASK, KVM_REG_SIZE_U32, KVM_REG_SIZE_U64, 16 }; 17 pub use kvm_bindings::{kvm_one_reg as Register, kvm_vcpu_init as VcpuInit, RegList}; 18 use serde::{Deserialize, Serialize}; 19 pub use {kvm_ioctls::Cap, kvm_ioctls::Kvm}; 20 21 use crate::kvm::{KvmError, KvmResult}; 22 23 // This macro gets the offset of a structure (i.e `str`) member (i.e `field`) without having 24 // an instance of that structure. 25 #[macro_export] 26 macro_rules! offset_of { 27 ($str:ty, $field:ident) => {{ 28 let tmp: std::mem::MaybeUninit<$str> = std::mem::MaybeUninit::uninit(); 29 let base = tmp.as_ptr(); 30 31 // Avoid warnings when nesting `unsafe` blocks. 32 #[allow(unused_unsafe)] 33 // SAFETY: The pointer is valid and aligned, just not initialised. Using `addr_of` ensures 34 // that we don't actually read from `base` (which would be UB) nor create an intermediate 35 // reference. 36 let member = unsafe { core::ptr::addr_of!((*base).$field) } as *const u8; 37 38 // Avoid warnings when nesting `unsafe` blocks. 39 #[allow(unused_unsafe)] 40 // SAFETY: The two pointers are within the same allocated object `tmp`. All requirements 41 // from offset_from are upheld. 42 unsafe { 43 member.offset_from(base as *const u8) as usize 44 } 45 }}; 46 } 47 48 // Following are macros that help with getting the ID of a aarch64 core register. 49 // The core register are represented by the user_pt_regs structure. Look for it in 50 // arch/arm64/include/uapi/asm/ptrace.h. 51 52 // Get the ID of a core register 53 #[macro_export] 54 macro_rules! arm64_core_reg_id { 55 ($size: tt, $offset: tt) => { 56 // The core registers of an arm64 machine are represented 57 // in kernel by the `kvm_regs` structure. This structure is a 58 // mix of 32, 64 and 128 bit fields: 59 // struct kvm_regs { 60 // struct user_pt_regs regs; 61 // 62 // __u64 sp_el1; 63 // __u64 elr_el1; 64 // 65 // __u64 spsr[KVM_NR_SPSR]; 66 // 67 // struct user_fpsimd_state fp_regs; 68 // }; 69 // struct user_pt_regs { 70 // __u64 regs[31]; 71 // __u64 sp; 72 // __u64 pc; 73 // __u64 pstate; 74 // }; 75 // The id of a core register can be obtained like this: 76 // offset = id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE). Thus, 77 // id = KVM_REG_ARM64 | KVM_REG_SIZE_U64/KVM_REG_SIZE_U32/KVM_REG_SIZE_U128 | KVM_REG_ARM_CORE | offset 78 KVM_REG_ARM64 as u64 79 | u64::from(KVM_REG_ARM_CORE) 80 | $size 81 | (($offset / mem::size_of::<u32>()) as u64) 82 }; 83 } 84 85 /// Specifies whether a particular register is a system register or not. 86 /// 87 /// The kernel splits the registers on aarch64 in core registers and system registers. 88 /// So, below we get the system registers by checking that they are not core registers. 89 /// 90 /// # Arguments 91 /// 92 /// * `regid` - The index of the register we are checking. 93 pub fn is_system_register(regid: u64) -> bool { 94 if (regid & KVM_REG_ARM_COPROC_MASK as u64) == KVM_REG_ARM_CORE as u64 { 95 return false; 96 } 97 98 let size = regid & KVM_REG_SIZE_MASK; 99 100 assert!( 101 !(size != KVM_REG_SIZE_U32 && size != KVM_REG_SIZE_U64), 102 "Unexpected register size for system register {size}" 103 ); 104 105 true 106 } 107 108 pub fn check_required_kvm_extensions(kvm: &Kvm) -> KvmResult<()> { 109 macro_rules! check_extension { 110 ($cap:expr) => { 111 if !kvm.check_extension($cap) { 112 return Err(KvmError::CapabilityMissing($cap)); 113 } 114 }; 115 } 116 117 // SetGuestDebug is required but some kernels have it implemented without the capability flag. 118 check_extension!(Cap::ImmediateExit); 119 check_extension!(Cap::Ioeventfd); 120 check_extension!(Cap::Irqchip); 121 check_extension!(Cap::Irqfd); 122 check_extension!(Cap::IrqRouting); 123 check_extension!(Cap::MpState); 124 check_extension!(Cap::OneReg); 125 check_extension!(Cap::UserMemory); 126 Ok(()) 127 } 128 129 #[derive(Clone, Default, Serialize, Deserialize)] 130 pub struct VcpuKvmState { 131 pub mp_state: kvm_mp_state, 132 pub core_regs: kvm_regs, 133 pub sys_regs: Vec<kvm_one_reg>, 134 } 135