diff options
Diffstat (limited to 'arch/arm64/kvm/hyp/nvhe/pkvm.c')
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/pkvm.c | 935 |
1 files changed, 822 insertions, 113 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c index 85d3b7ae720f..8911338961c5 100644 --- a/arch/arm64/kvm/hyp/nvhe/pkvm.c +++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c @@ -6,180 +6,889 @@ #include <linux/kvm_host.h> #include <linux/mm.h> -#include <nvhe/fixed_config.h> + +#include <asm/kvm_emulate.h> + +#include <nvhe/mem_protect.h> +#include <nvhe/memory.h> +#include <nvhe/pkvm.h> #include <nvhe/trap_handler.h> +/* Used by icache_is_aliasing(). */ +unsigned long __icache_flags; + +/* Used by kvm_get_vttbr(). */ +unsigned int kvm_arm_vmid_bits; + +unsigned int kvm_host_sve_max_vl; + /* - * Set trap register values based on features in ID_AA64PFR0. + * The currently loaded hyp vCPU for each physical CPU. Used in protected mode + * for both protected and non-protected VMs. */ -static void pvm_init_traps_aa64pfr0(struct kvm_vcpu *vcpu) +static DEFINE_PER_CPU(struct pkvm_hyp_vcpu *, loaded_hyp_vcpu); + +static void pkvm_vcpu_reset_hcr(struct kvm_vcpu *vcpu) +{ + vcpu->arch.hcr_el2 = HCR_GUEST_FLAGS; + + if (has_hvhe()) + vcpu->arch.hcr_el2 |= HCR_E2H; + + if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN)) { + /* route synchronous external abort exceptions to EL2 */ + vcpu->arch.hcr_el2 |= HCR_TEA; + /* trap error record accesses */ + vcpu->arch.hcr_el2 |= HCR_TERR; + } + + if (cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) + vcpu->arch.hcr_el2 |= HCR_FWB; + + if (cpus_have_final_cap(ARM64_HAS_EVT) && + !cpus_have_final_cap(ARM64_MISMATCHED_CACHE_TYPE) && + kvm_read_vm_id_reg(vcpu->kvm, SYS_CTR_EL0) == read_cpuid(CTR_EL0)) + vcpu->arch.hcr_el2 |= HCR_TID4; + else + vcpu->arch.hcr_el2 |= HCR_TID2; + + if (vcpu_has_ptrauth(vcpu)) + vcpu->arch.hcr_el2 |= (HCR_API | HCR_APK); + + if (kvm_has_mte(vcpu->kvm)) + vcpu->arch.hcr_el2 |= HCR_ATA; +} + +static void pvm_init_traps_hcr(struct kvm_vcpu *vcpu) { - const u64 feature_ids = pvm_read_id_reg(vcpu, SYS_ID_AA64PFR0_EL1); - u64 hcr_set = HCR_RW; - u64 hcr_clear = 0; - u64 cptr_set = 0; + struct kvm *kvm = vcpu->kvm; + u64 val = vcpu->arch.hcr_el2; - /* Protected KVM does not support AArch32 guests. */ - BUILD_BUG_ON(FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_EL0), - PVM_ID_AA64PFR0_RESTRICT_UNSIGNED) != ID_AA64PFR0_EL1_ELx_64BIT_ONLY); - BUILD_BUG_ON(FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_EL1), - PVM_ID_AA64PFR0_RESTRICT_UNSIGNED) != ID_AA64PFR0_EL1_ELx_64BIT_ONLY); + /* No support for AArch32. */ + val |= HCR_RW; /* - * Linux guests assume support for floating-point and Advanced SIMD. Do - * not change the trapping behavior for these from the KVM default. + * Always trap: + * - Feature id registers: to control features exposed to guests + * - Implementation-defined features */ - BUILD_BUG_ON(!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_FP), - PVM_ID_AA64PFR0_ALLOW)); - BUILD_BUG_ON(!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_AdvSIMD), - PVM_ID_AA64PFR0_ALLOW)); + val |= HCR_TACR | HCR_TIDCP | HCR_TID3 | HCR_TID1; + + if (!kvm_has_feat(kvm, ID_AA64PFR0_EL1, RAS, IMP)) { + val |= HCR_TERR | HCR_TEA; + val &= ~(HCR_FIEN); + } + + if (!kvm_has_feat(kvm, ID_AA64PFR0_EL1, AMU, IMP)) + val &= ~(HCR_AMVOFFEN); + + if (!kvm_has_feat(kvm, ID_AA64PFR1_EL1, MTE, IMP)) { + val |= HCR_TID5; + val &= ~(HCR_DCT | HCR_ATA); + } + + if (!kvm_has_feat(kvm, ID_AA64MMFR1_EL1, LO, IMP)) + val |= HCR_TLOR; - /* Trap RAS unless all current versions are supported */ - if (FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_RAS), feature_ids) < - ID_AA64PFR0_EL1_RAS_V1P1) { - hcr_set |= HCR_TERR | HCR_TEA; - hcr_clear |= HCR_FIEN; + vcpu->arch.hcr_el2 = val; +} + +static void pvm_init_traps_mdcr(struct kvm_vcpu *vcpu) +{ + struct kvm *kvm = vcpu->kvm; + u64 val = vcpu->arch.mdcr_el2; + + if (!kvm_has_feat(kvm, ID_AA64DFR0_EL1, PMUVer, IMP)) { + val |= MDCR_EL2_TPM | MDCR_EL2_TPMCR; + val &= ~(MDCR_EL2_HPME | MDCR_EL2_MTPME | MDCR_EL2_HPMN_MASK); } - /* Trap AMU */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_AMU), feature_ids)) { - hcr_clear |= HCR_AMVOFFEN; - cptr_set |= CPTR_EL2_TAM; + if (!kvm_has_feat(kvm, ID_AA64DFR0_EL1, DebugVer, IMP)) + val |= MDCR_EL2_TDRA | MDCR_EL2_TDA; + + if (!kvm_has_feat(kvm, ID_AA64DFR0_EL1, DoubleLock, IMP)) + val |= MDCR_EL2_TDOSA; + + if (!kvm_has_feat(kvm, ID_AA64DFR0_EL1, PMSVer, IMP)) { + val |= MDCR_EL2_TPMS; + val &= ~MDCR_EL2_E2PB_MASK; } - /* Trap SVE */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_SVE), feature_ids)) - cptr_set |= CPTR_EL2_TZ; + if (!kvm_has_feat(kvm, ID_AA64DFR0_EL1, TraceFilt, IMP)) + val |= MDCR_EL2_TTRF; + + if (!kvm_has_feat(kvm, ID_AA64DFR0_EL1, ExtTrcBuff, IMP)) + val |= MDCR_EL2_E2TB_MASK; + + /* Trap Debug Communications Channel registers */ + if (!kvm_has_feat(kvm, ID_AA64MMFR0_EL1, FGT, IMP)) + val |= MDCR_EL2_TDCC; - vcpu->arch.hcr_el2 |= hcr_set; - vcpu->arch.hcr_el2 &= ~hcr_clear; - vcpu->arch.cptr_el2 |= cptr_set; + vcpu->arch.mdcr_el2 = val; } /* - * Set trap register values based on features in ID_AA64PFR1. + * Check that cpu features that are neither trapped nor supported are not + * enabled for protected VMs. */ -static void pvm_init_traps_aa64pfr1(struct kvm_vcpu *vcpu) +static int pkvm_check_pvm_cpu_features(struct kvm_vcpu *vcpu) { - const u64 feature_ids = pvm_read_id_reg(vcpu, SYS_ID_AA64PFR1_EL1); - u64 hcr_set = 0; - u64 hcr_clear = 0; + struct kvm *kvm = vcpu->kvm; - /* Memory Tagging: Trap and Treat as Untagged if not supported. */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR1_EL1_MTE), feature_ids)) { - hcr_set |= HCR_TID5; - hcr_clear |= HCR_DCT | HCR_ATA; - } + /* No AArch32 support for protected guests. */ + if (kvm_has_feat(kvm, ID_AA64PFR0_EL1, EL0, AARCH32) || + kvm_has_feat(kvm, ID_AA64PFR0_EL1, EL1, AARCH32)) + return -EINVAL; - vcpu->arch.hcr_el2 |= hcr_set; - vcpu->arch.hcr_el2 &= ~hcr_clear; + /* + * Linux guests assume support for floating-point and Advanced SIMD. Do + * not change the trapping behavior for these from the KVM default. + */ + if (!kvm_has_feat(kvm, ID_AA64PFR0_EL1, FP, IMP) || + !kvm_has_feat(kvm, ID_AA64PFR0_EL1, AdvSIMD, IMP)) + return -EINVAL; + + /* No SME support in KVM right now. Check to catch if it changes. */ + if (kvm_has_feat(kvm, ID_AA64PFR1_EL1, SME, IMP)) + return -EINVAL; + + return 0; } /* - * Set trap register values based on features in ID_AA64DFR0. + * Initialize trap register values in protected mode. */ -static void pvm_init_traps_aa64dfr0(struct kvm_vcpu *vcpu) +static int pkvm_vcpu_init_traps(struct pkvm_hyp_vcpu *hyp_vcpu) { - const u64 feature_ids = pvm_read_id_reg(vcpu, SYS_ID_AA64DFR0_EL1); - u64 mdcr_set = 0; - u64 mdcr_clear = 0; - u64 cptr_set = 0; + struct kvm_vcpu *vcpu = &hyp_vcpu->vcpu; + int ret; - /* Trap/constrain PMU */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), feature_ids)) { - mdcr_set |= MDCR_EL2_TPM | MDCR_EL2_TPMCR; - mdcr_clear |= MDCR_EL2_HPME | MDCR_EL2_MTPME | - MDCR_EL2_HPMN_MASK; - } + vcpu->arch.mdcr_el2 = 0; - /* Trap Debug */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_DebugVer), feature_ids)) - mdcr_set |= MDCR_EL2_TDRA | MDCR_EL2_TDA | MDCR_EL2_TDE; + pkvm_vcpu_reset_hcr(vcpu); - /* Trap OS Double Lock */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_DoubleLock), feature_ids)) - mdcr_set |= MDCR_EL2_TDOSA; + if ((!pkvm_hyp_vcpu_is_protected(hyp_vcpu))) { + struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu; - /* Trap SPE */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMSVer), feature_ids)) { - mdcr_set |= MDCR_EL2_TPMS; - mdcr_clear |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT; + /* Trust the host for non-protected vcpu features. */ + vcpu->arch.hcrx_el2 = host_vcpu->arch.hcrx_el2; + memcpy(vcpu->arch.fgt, host_vcpu->arch.fgt, sizeof(vcpu->arch.fgt)); + return 0; } - /* Trap Trace Filter */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_TraceFilt), feature_ids)) - mdcr_set |= MDCR_EL2_TTRF; + ret = pkvm_check_pvm_cpu_features(vcpu); + if (ret) + return ret; - /* Trap Trace */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_TraceVer), feature_ids)) - cptr_set |= CPTR_EL2_TTA; + pvm_init_traps_hcr(vcpu); + pvm_init_traps_mdcr(vcpu); + vcpu_set_hcrx(vcpu); - vcpu->arch.mdcr_el2 |= mdcr_set; - vcpu->arch.mdcr_el2 &= ~mdcr_clear; - vcpu->arch.cptr_el2 |= cptr_set; + return 0; } /* - * Set trap register values based on features in ID_AA64MMFR0. + * Start the VM table handle at the offset defined instead of at 0. + * Mainly for sanity checking and debugging. + */ +#define HANDLE_OFFSET 0x1000 + +/* + * Marks a reserved but not yet used entry in the VM table. */ -static void pvm_init_traps_aa64mmfr0(struct kvm_vcpu *vcpu) +#define RESERVED_ENTRY ((void *)0xa110ca7ed) + +static unsigned int vm_handle_to_idx(pkvm_handle_t handle) { - const u64 feature_ids = pvm_read_id_reg(vcpu, SYS_ID_AA64MMFR0_EL1); - u64 mdcr_set = 0; + return handle - HANDLE_OFFSET; +} - /* Trap Debug Communications Channel registers */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64MMFR0_EL1_FGT), feature_ids)) - mdcr_set |= MDCR_EL2_TDCC; +static pkvm_handle_t idx_to_vm_handle(unsigned int idx) +{ + return idx + HANDLE_OFFSET; +} - vcpu->arch.mdcr_el2 |= mdcr_set; +/* + * Spinlock for protecting state related to the VM table. Protects writes + * to 'vm_table', 'nr_table_entries', and other per-vm state on initialization. + * Also protects reads and writes to 'last_hyp_vcpu_lookup'. + */ +DEFINE_HYP_SPINLOCK(vm_table_lock); + +/* + * A table that tracks all VMs in protected mode. + * Allocated during hyp initialization and setup. + */ +static struct pkvm_hyp_vm **vm_table; + +void pkvm_hyp_vm_table_init(void *tbl) +{ + WARN_ON(vm_table); + vm_table = tbl; } /* - * Set trap register values based on features in ID_AA64MMFR1. + * Return the hyp vm structure corresponding to the handle. */ -static void pvm_init_traps_aa64mmfr1(struct kvm_vcpu *vcpu) +static struct pkvm_hyp_vm *get_vm_by_handle(pkvm_handle_t handle) +{ + unsigned int idx = vm_handle_to_idx(handle); + + if (unlikely(idx >= KVM_MAX_PVMS)) + return NULL; + + /* A reserved entry doesn't represent an initialized VM. */ + if (unlikely(vm_table[idx] == RESERVED_ENTRY)) + return NULL; + + return vm_table[idx]; +} + +struct pkvm_hyp_vcpu *pkvm_load_hyp_vcpu(pkvm_handle_t handle, + unsigned int vcpu_idx) +{ + struct pkvm_hyp_vcpu *hyp_vcpu = NULL; + struct pkvm_hyp_vm *hyp_vm; + + /* Cannot load a new vcpu without putting the old one first. */ + if (__this_cpu_read(loaded_hyp_vcpu)) + return NULL; + + hyp_spin_lock(&vm_table_lock); + hyp_vm = get_vm_by_handle(handle); + if (!hyp_vm || hyp_vm->kvm.created_vcpus <= vcpu_idx) + goto unlock; + + hyp_vcpu = hyp_vm->vcpus[vcpu_idx]; + if (!hyp_vcpu) + goto unlock; + + /* Ensure vcpu isn't loaded on more than one cpu simultaneously. */ + if (unlikely(hyp_vcpu->loaded_hyp_vcpu)) { + hyp_vcpu = NULL; + goto unlock; + } + + hyp_vcpu->loaded_hyp_vcpu = this_cpu_ptr(&loaded_hyp_vcpu); + hyp_page_ref_inc(hyp_virt_to_page(hyp_vm)); +unlock: + hyp_spin_unlock(&vm_table_lock); + + if (hyp_vcpu) + __this_cpu_write(loaded_hyp_vcpu, hyp_vcpu); + return hyp_vcpu; +} + +void pkvm_put_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu) +{ + struct pkvm_hyp_vm *hyp_vm = pkvm_hyp_vcpu_to_hyp_vm(hyp_vcpu); + + hyp_spin_lock(&vm_table_lock); + hyp_vcpu->loaded_hyp_vcpu = NULL; + __this_cpu_write(loaded_hyp_vcpu, NULL); + hyp_page_ref_dec(hyp_virt_to_page(hyp_vm)); + hyp_spin_unlock(&vm_table_lock); +} + +struct pkvm_hyp_vcpu *pkvm_get_loaded_hyp_vcpu(void) +{ + return __this_cpu_read(loaded_hyp_vcpu); + +} + +struct pkvm_hyp_vm *get_pkvm_hyp_vm(pkvm_handle_t handle) +{ + struct pkvm_hyp_vm *hyp_vm; + + hyp_spin_lock(&vm_table_lock); + hyp_vm = get_vm_by_handle(handle); + if (hyp_vm) + hyp_page_ref_inc(hyp_virt_to_page(hyp_vm)); + hyp_spin_unlock(&vm_table_lock); + + return hyp_vm; +} + +void put_pkvm_hyp_vm(struct pkvm_hyp_vm *hyp_vm) +{ + hyp_spin_lock(&vm_table_lock); + hyp_page_ref_dec(hyp_virt_to_page(hyp_vm)); + hyp_spin_unlock(&vm_table_lock); +} + +struct pkvm_hyp_vm *get_np_pkvm_hyp_vm(pkvm_handle_t handle) { - const u64 feature_ids = pvm_read_id_reg(vcpu, SYS_ID_AA64MMFR1_EL1); - u64 hcr_set = 0; + struct pkvm_hyp_vm *hyp_vm = get_pkvm_hyp_vm(handle); - /* Trap LOR */ - if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64MMFR1_EL1_LO), feature_ids)) - hcr_set |= HCR_TLOR; + if (hyp_vm && pkvm_hyp_vm_is_protected(hyp_vm)) { + put_pkvm_hyp_vm(hyp_vm); + hyp_vm = NULL; + } - vcpu->arch.hcr_el2 |= hcr_set; + return hyp_vm; +} + +static void pkvm_init_features_from_host(struct pkvm_hyp_vm *hyp_vm, const struct kvm *host_kvm) +{ + struct kvm *kvm = &hyp_vm->kvm; + unsigned long host_arch_flags = READ_ONCE(host_kvm->arch.flags); + DECLARE_BITMAP(allowed_features, KVM_VCPU_MAX_FEATURES); + + /* CTR_EL0 is always under host control, even for protected VMs. */ + hyp_vm->kvm.arch.ctr_el0 = host_kvm->arch.ctr_el0; + + /* Preserve the vgic model so that GICv3 emulation works */ + hyp_vm->kvm.arch.vgic.vgic_model = host_kvm->arch.vgic.vgic_model; + + if (test_bit(KVM_ARCH_FLAG_MTE_ENABLED, &host_kvm->arch.flags)) + set_bit(KVM_ARCH_FLAG_MTE_ENABLED, &kvm->arch.flags); + + /* No restrictions for non-protected VMs. */ + if (!kvm_vm_is_protected(kvm)) { + hyp_vm->kvm.arch.flags = host_arch_flags; + + bitmap_copy(kvm->arch.vcpu_features, + host_kvm->arch.vcpu_features, + KVM_VCPU_MAX_FEATURES); + + if (test_bit(KVM_ARCH_FLAG_WRITABLE_IMP_ID_REGS, &host_arch_flags)) + hyp_vm->kvm.arch.midr_el1 = host_kvm->arch.midr_el1; + + return; + } + + bitmap_zero(allowed_features, KVM_VCPU_MAX_FEATURES); + + set_bit(KVM_ARM_VCPU_PSCI_0_2, allowed_features); + + if (kvm_pvm_ext_allowed(KVM_CAP_ARM_PMU_V3)) + set_bit(KVM_ARM_VCPU_PMU_V3, allowed_features); + + if (kvm_pvm_ext_allowed(KVM_CAP_ARM_PTRAUTH_ADDRESS)) + set_bit(KVM_ARM_VCPU_PTRAUTH_ADDRESS, allowed_features); + + if (kvm_pvm_ext_allowed(KVM_CAP_ARM_PTRAUTH_GENERIC)) + set_bit(KVM_ARM_VCPU_PTRAUTH_GENERIC, allowed_features); + + if (kvm_pvm_ext_allowed(KVM_CAP_ARM_SVE)) { + set_bit(KVM_ARM_VCPU_SVE, allowed_features); + kvm->arch.flags |= host_arch_flags & BIT(KVM_ARCH_FLAG_GUEST_HAS_SVE); + } + + bitmap_and(kvm->arch.vcpu_features, host_kvm->arch.vcpu_features, + allowed_features, KVM_VCPU_MAX_FEATURES); +} + +static void unpin_host_vcpu(struct kvm_vcpu *host_vcpu) +{ + if (host_vcpu) + hyp_unpin_shared_mem(host_vcpu, host_vcpu + 1); +} + +static void unpin_host_sve_state(struct pkvm_hyp_vcpu *hyp_vcpu) +{ + void *sve_state; + + if (!vcpu_has_feature(&hyp_vcpu->vcpu, KVM_ARM_VCPU_SVE)) + return; + + sve_state = kern_hyp_va(hyp_vcpu->vcpu.arch.sve_state); + hyp_unpin_shared_mem(sve_state, + sve_state + vcpu_sve_state_size(&hyp_vcpu->vcpu)); +} + +static void unpin_host_vcpus(struct pkvm_hyp_vcpu *hyp_vcpus[], + unsigned int nr_vcpus) +{ + int i; + + for (i = 0; i < nr_vcpus; i++) { + struct pkvm_hyp_vcpu *hyp_vcpu = hyp_vcpus[i]; + + if (!hyp_vcpu) + continue; + + unpin_host_vcpu(hyp_vcpu->host_vcpu); + unpin_host_sve_state(hyp_vcpu); + } +} + +static void init_pkvm_hyp_vm(struct kvm *host_kvm, struct pkvm_hyp_vm *hyp_vm, + unsigned int nr_vcpus, pkvm_handle_t handle) +{ + struct kvm_s2_mmu *mmu = &hyp_vm->kvm.arch.mmu; + int idx = vm_handle_to_idx(handle); + + hyp_vm->kvm.arch.pkvm.handle = handle; + + hyp_vm->host_kvm = host_kvm; + hyp_vm->kvm.created_vcpus = nr_vcpus; + hyp_vm->kvm.arch.pkvm.is_protected = READ_ONCE(host_kvm->arch.pkvm.is_protected); + hyp_vm->kvm.arch.pkvm.is_created = true; + hyp_vm->kvm.arch.flags = 0; + pkvm_init_features_from_host(hyp_vm, host_kvm); + + /* VMID 0 is reserved for the host */ + atomic64_set(&mmu->vmid.id, idx + 1); + + mmu->vtcr = host_mmu.arch.mmu.vtcr; + mmu->arch = &hyp_vm->kvm.arch; + mmu->pgt = &hyp_vm->pgt; +} + +static int pkvm_vcpu_init_sve(struct pkvm_hyp_vcpu *hyp_vcpu, struct kvm_vcpu *host_vcpu) +{ + struct kvm_vcpu *vcpu = &hyp_vcpu->vcpu; + unsigned int sve_max_vl; + size_t sve_state_size; + void *sve_state; + int ret = 0; + + if (!vcpu_has_feature(vcpu, KVM_ARM_VCPU_SVE)) { + vcpu_clear_flag(vcpu, VCPU_SVE_FINALIZED); + return 0; + } + + /* Limit guest vector length to the maximum supported by the host. */ + sve_max_vl = min(READ_ONCE(host_vcpu->arch.sve_max_vl), kvm_host_sve_max_vl); + sve_state_size = sve_state_size_from_vl(sve_max_vl); + sve_state = kern_hyp_va(READ_ONCE(host_vcpu->arch.sve_state)); + + if (!sve_state || !sve_state_size) { + ret = -EINVAL; + goto err; + } + + ret = hyp_pin_shared_mem(sve_state, sve_state + sve_state_size); + if (ret) + goto err; + + vcpu->arch.sve_state = sve_state; + vcpu->arch.sve_max_vl = sve_max_vl; + + return 0; +err: + clear_bit(KVM_ARM_VCPU_SVE, vcpu->kvm->arch.vcpu_features); + return ret; +} + +static int init_pkvm_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu, + struct pkvm_hyp_vm *hyp_vm, + struct kvm_vcpu *host_vcpu) +{ + int ret = 0; + + if (hyp_pin_shared_mem(host_vcpu, host_vcpu + 1)) + return -EBUSY; + + hyp_vcpu->host_vcpu = host_vcpu; + + hyp_vcpu->vcpu.kvm = &hyp_vm->kvm; + hyp_vcpu->vcpu.vcpu_id = READ_ONCE(host_vcpu->vcpu_id); + hyp_vcpu->vcpu.vcpu_idx = READ_ONCE(host_vcpu->vcpu_idx); + + hyp_vcpu->vcpu.arch.hw_mmu = &hyp_vm->kvm.arch.mmu; + hyp_vcpu->vcpu.arch.cflags = READ_ONCE(host_vcpu->arch.cflags); + hyp_vcpu->vcpu.arch.mp_state.mp_state = KVM_MP_STATE_STOPPED; + + if (pkvm_hyp_vcpu_is_protected(hyp_vcpu)) + kvm_init_pvm_id_regs(&hyp_vcpu->vcpu); + + ret = pkvm_vcpu_init_traps(hyp_vcpu); + if (ret) + goto done; + + ret = pkvm_vcpu_init_sve(hyp_vcpu, host_vcpu); +done: + if (ret) + unpin_host_vcpu(host_vcpu); + return ret; +} + +static int find_free_vm_table_entry(void) +{ + int i; + + for (i = 0; i < KVM_MAX_PVMS; ++i) { + if (!vm_table[i]) + return i; + } + + return -ENOMEM; } /* - * Set baseline trap register values. + * Reserve a VM table entry. + * + * Return a unique handle to the VM on success, + * negative error code on failure. */ -static void pvm_init_trap_regs(struct kvm_vcpu *vcpu) +static int allocate_vm_table_entry(void) { - const u64 hcr_trap_feat_regs = HCR_TID3; - const u64 hcr_trap_impdef = HCR_TACR | HCR_TIDCP | HCR_TID1; + int idx; + + hyp_assert_lock_held(&vm_table_lock); /* - * Always trap: - * - Feature id registers: to control features exposed to guests - * - Implementation-defined features + * Initializing protected state might have failed, yet a malicious + * host could trigger this function. Thus, ensure that 'vm_table' + * exists. + */ + if (unlikely(!vm_table)) + return -EINVAL; + + idx = find_free_vm_table_entry(); + if (unlikely(idx < 0)) + return idx; + + vm_table[idx] = RESERVED_ENTRY; + + return idx; +} + +static int __insert_vm_table_entry(pkvm_handle_t handle, + struct pkvm_hyp_vm *hyp_vm) +{ + unsigned int idx; + + hyp_assert_lock_held(&vm_table_lock); + + /* + * Initializing protected state might have failed, yet a malicious + * host could trigger this function. Thus, ensure that 'vm_table' + * exists. */ - vcpu->arch.hcr_el2 |= hcr_trap_feat_regs | hcr_trap_impdef; + if (unlikely(!vm_table)) + return -EINVAL; - /* Clear res0 and set res1 bits to trap potential new features. */ - vcpu->arch.hcr_el2 &= ~(HCR_RES0); - vcpu->arch.mdcr_el2 &= ~(MDCR_EL2_RES0); - vcpu->arch.cptr_el2 |= CPTR_NVHE_EL2_RES1; - vcpu->arch.cptr_el2 &= ~(CPTR_NVHE_EL2_RES0); + idx = vm_handle_to_idx(handle); + if (unlikely(idx >= KVM_MAX_PVMS)) + return -EINVAL; + + if (unlikely(vm_table[idx] != RESERVED_ENTRY)) + return -EINVAL; + + vm_table[idx] = hyp_vm; + + return 0; } /* - * Initialize trap register values for protected VMs. + * Insert a pointer to the initialized VM into the VM table. + * + * Return 0 on success, or negative error code on failure. */ -void __pkvm_vcpu_init_traps(struct kvm_vcpu *vcpu) +static int insert_vm_table_entry(pkvm_handle_t handle, + struct pkvm_hyp_vm *hyp_vm) { - pvm_init_trap_regs(vcpu); - pvm_init_traps_aa64pfr0(vcpu); - pvm_init_traps_aa64pfr1(vcpu); - pvm_init_traps_aa64dfr0(vcpu); - pvm_init_traps_aa64mmfr0(vcpu); - pvm_init_traps_aa64mmfr1(vcpu); + int ret; + + hyp_spin_lock(&vm_table_lock); + ret = __insert_vm_table_entry(handle, hyp_vm); + hyp_spin_unlock(&vm_table_lock); + + return ret; +} + +/* + * Deallocate and remove the VM table entry corresponding to the handle. + */ +static void remove_vm_table_entry(pkvm_handle_t handle) +{ + hyp_assert_lock_held(&vm_table_lock); + vm_table[vm_handle_to_idx(handle)] = NULL; +} + +static size_t pkvm_get_hyp_vm_size(unsigned int nr_vcpus) +{ + return size_add(sizeof(struct pkvm_hyp_vm), + size_mul(sizeof(struct pkvm_hyp_vcpu *), nr_vcpus)); +} + +static void *map_donated_memory_noclear(unsigned long host_va, size_t size) +{ + void *va = (void *)kern_hyp_va(host_va); + + if (!PAGE_ALIGNED(va)) + return NULL; + + if (__pkvm_host_donate_hyp(hyp_virt_to_pfn(va), + PAGE_ALIGN(size) >> PAGE_SHIFT)) + return NULL; + + return va; +} + +static void *map_donated_memory(unsigned long host_va, size_t size) +{ + void *va = map_donated_memory_noclear(host_va, size); + + if (va) + memset(va, 0, size); + + return va; +} + +static void __unmap_donated_memory(void *va, size_t size) +{ + kvm_flush_dcache_to_poc(va, size); + WARN_ON(__pkvm_hyp_donate_host(hyp_virt_to_pfn(va), + PAGE_ALIGN(size) >> PAGE_SHIFT)); +} + +static void unmap_donated_memory(void *va, size_t size) +{ + if (!va) + return; + + memset(va, 0, size); + __unmap_donated_memory(va, size); +} + +static void unmap_donated_memory_noclear(void *va, size_t size) +{ + if (!va) + return; + + __unmap_donated_memory(va, size); +} + +/* + * Reserves an entry in the hypervisor for a new VM in protected mode. + * + * Return a unique handle to the VM on success, negative error code on failure. + */ +int __pkvm_reserve_vm(void) +{ + int ret; + + hyp_spin_lock(&vm_table_lock); + ret = allocate_vm_table_entry(); + hyp_spin_unlock(&vm_table_lock); + + if (ret < 0) + return ret; + + return idx_to_vm_handle(ret); +} + +/* + * Removes a reserved entry, but only if is hasn't been used yet. + * Otherwise, the VM needs to be destroyed. + */ +void __pkvm_unreserve_vm(pkvm_handle_t handle) +{ + unsigned int idx = vm_handle_to_idx(handle); + + if (unlikely(!vm_table)) + return; + + hyp_spin_lock(&vm_table_lock); + if (likely(idx < KVM_MAX_PVMS && vm_table[idx] == RESERVED_ENTRY)) + remove_vm_table_entry(handle); + hyp_spin_unlock(&vm_table_lock); +} + +/* + * Initialize the hypervisor copy of the VM state using host-donated memory. + * + * Unmap the donated memory from the host at stage 2. + * + * host_kvm: A pointer to the host's struct kvm. + * vm_hva: The host va of the area being donated for the VM state. + * Must be page aligned. + * pgd_hva: The host va of the area being donated for the stage-2 PGD for + * the VM. Must be page aligned. Its size is implied by the VM's + * VTCR. + * + * Return 0 success, negative error code on failure. + */ +int __pkvm_init_vm(struct kvm *host_kvm, unsigned long vm_hva, + unsigned long pgd_hva) +{ + struct pkvm_hyp_vm *hyp_vm = NULL; + size_t vm_size, pgd_size; + unsigned int nr_vcpus; + pkvm_handle_t handle; + void *pgd = NULL; + int ret; + + ret = hyp_pin_shared_mem(host_kvm, host_kvm + 1); + if (ret) + return ret; + + nr_vcpus = READ_ONCE(host_kvm->created_vcpus); + if (nr_vcpus < 1) { + ret = -EINVAL; + goto err_unpin_kvm; + } + + handle = READ_ONCE(host_kvm->arch.pkvm.handle); + if (unlikely(handle < HANDLE_OFFSET)) { + ret = -EINVAL; + goto err_unpin_kvm; + } + + vm_size = pkvm_get_hyp_vm_size(nr_vcpus); + pgd_size = kvm_pgtable_stage2_pgd_size(host_mmu.arch.mmu.vtcr); + + ret = -ENOMEM; + + hyp_vm = map_donated_memory(vm_hva, vm_size); + if (!hyp_vm) + goto err_remove_mappings; + + pgd = map_donated_memory_noclear(pgd_hva, pgd_size); + if (!pgd) + goto err_remove_mappings; + + init_pkvm_hyp_vm(host_kvm, hyp_vm, nr_vcpus, handle); + + ret = kvm_guest_prepare_stage2(hyp_vm, pgd); + if (ret) + goto err_remove_mappings; + + /* Must be called last since this publishes the VM. */ + ret = insert_vm_table_entry(handle, hyp_vm); + if (ret) + goto err_remove_mappings; + + return 0; + +err_remove_mappings: + unmap_donated_memory(hyp_vm, vm_size); + unmap_donated_memory(pgd, pgd_size); +err_unpin_kvm: + hyp_unpin_shared_mem(host_kvm, host_kvm + 1); + return ret; +} + +/* + * Initialize the hypervisor copy of the vCPU state using host-donated memory. + * + * handle: The hypervisor handle for the vm. + * host_vcpu: A pointer to the corresponding host vcpu. + * vcpu_hva: The host va of the area being donated for the vcpu state. + * Must be page aligned. The size of the area must be equal to + * the page-aligned size of 'struct pkvm_hyp_vcpu'. + * Return 0 on success, negative error code on failure. + */ +int __pkvm_init_vcpu(pkvm_handle_t handle, struct kvm_vcpu *host_vcpu, + unsigned long vcpu_hva) +{ + struct pkvm_hyp_vcpu *hyp_vcpu; + struct pkvm_hyp_vm *hyp_vm; + unsigned int idx; + int ret; + + hyp_vcpu = map_donated_memory(vcpu_hva, sizeof(*hyp_vcpu)); + if (!hyp_vcpu) + return -ENOMEM; + + hyp_spin_lock(&vm_table_lock); + + hyp_vm = get_vm_by_handle(handle); + if (!hyp_vm) { + ret = -ENOENT; + goto unlock; + } + + ret = init_pkvm_hyp_vcpu(hyp_vcpu, hyp_vm, host_vcpu); + if (ret) + goto unlock; + + idx = hyp_vcpu->vcpu.vcpu_idx; + if (idx >= hyp_vm->kvm.created_vcpus) { + ret = -EINVAL; + goto unlock; + } + + if (hyp_vm->vcpus[idx]) { + ret = -EINVAL; + goto unlock; + } + + hyp_vm->vcpus[idx] = hyp_vcpu; +unlock: + hyp_spin_unlock(&vm_table_lock); + + if (ret) + unmap_donated_memory(hyp_vcpu, sizeof(*hyp_vcpu)); + return ret; +} + +static void +teardown_donated_memory(struct kvm_hyp_memcache *mc, void *addr, size_t size) +{ + size = PAGE_ALIGN(size); + memset(addr, 0, size); + + for (void *start = addr; start < addr + size; start += PAGE_SIZE) + push_hyp_memcache(mc, start, hyp_virt_to_phys); + + unmap_donated_memory_noclear(addr, size); +} + +int __pkvm_teardown_vm(pkvm_handle_t handle) +{ + struct kvm_hyp_memcache *mc, *stage2_mc; + struct pkvm_hyp_vm *hyp_vm; + struct kvm *host_kvm; + unsigned int idx; + size_t vm_size; + int err; + + hyp_spin_lock(&vm_table_lock); + hyp_vm = get_vm_by_handle(handle); + if (!hyp_vm) { + err = -ENOENT; + goto err_unlock; + } + + if (WARN_ON(hyp_page_count(hyp_vm))) { + err = -EBUSY; + goto err_unlock; + } + + host_kvm = hyp_vm->host_kvm; + + /* Ensure the VMID is clean before it can be reallocated */ + __kvm_tlb_flush_vmid(&hyp_vm->kvm.arch.mmu); + remove_vm_table_entry(handle); + hyp_spin_unlock(&vm_table_lock); + + /* Reclaim guest pages (including page-table pages) */ + mc = &host_kvm->arch.pkvm.teardown_mc; + stage2_mc = &host_kvm->arch.pkvm.stage2_teardown_mc; + reclaim_pgtable_pages(hyp_vm, stage2_mc); + unpin_host_vcpus(hyp_vm->vcpus, hyp_vm->kvm.created_vcpus); + + /* Push the metadata pages to the teardown memcache */ + for (idx = 0; idx < hyp_vm->kvm.created_vcpus; ++idx) { + struct pkvm_hyp_vcpu *hyp_vcpu = hyp_vm->vcpus[idx]; + struct kvm_hyp_memcache *vcpu_mc; + + if (!hyp_vcpu) + continue; + + vcpu_mc = &hyp_vcpu->vcpu.arch.pkvm_memcache; + + while (vcpu_mc->nr_pages) { + void *addr = pop_hyp_memcache(vcpu_mc, hyp_phys_to_virt); + + push_hyp_memcache(stage2_mc, addr, hyp_virt_to_phys); + unmap_donated_memory_noclear(addr, PAGE_SIZE); + } + + teardown_donated_memory(mc, hyp_vcpu, sizeof(*hyp_vcpu)); + } + + vm_size = pkvm_get_hyp_vm_size(hyp_vm->kvm.created_vcpus); + teardown_donated_memory(mc, hyp_vm, vm_size); + hyp_unpin_shared_mem(host_kvm, host_kvm + 1); + return 0; + +err_unlock: + hyp_spin_unlock(&vm_table_lock); + return err; } |
