// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2020 - Google Inc
* Author: Andrew Scull <[email protected]>
*/
#include <hyp/adjust_pc.h>
#include <asm/pgtable-types.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_host.h>
#include <asm/kvm_hyp.h>
#include <asm/kvm_mmu.h>
#include <nvhe/ffa.h>
#include <nvhe/mem_protect.h>
#include <nvhe/mm.h>
#include <nvhe/pkvm.h>
#include <nvhe/trap_handler.h>
DEFINE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
void __kvm_hyp_host_forward_smc(struct kvm_cpu_context *host_ctxt);
static void __hyp_sve_save_guest(struct kvm_vcpu *vcpu)
{
__vcpu_sys_reg(vcpu, ZCR_EL1) = read_sysreg_el1(SYS_ZCR);
/*
* On saving/restoring guest sve state, always use the maximum VL for
* the guest. The layout of the data when saving the sve state depends
* on the VL, so use a consistent (i.e., the maximum) guest VL.
*/
sve_cond_update_zcr_vq(vcpu_sve_max_vq(vcpu) - 1, SYS_ZCR_EL2);
__sve_save_state(vcpu_sve_pffr(vcpu), &vcpu->arch.ctxt.fp_regs.fpsr, true);
write_sysreg_s(ZCR_ELx_LEN_MASK, SYS_ZCR_EL2);
}
static void __hyp_sve_restore_host(void)
{
struct cpu_sve_state *sve_state = *host_data_ptr(sve_state);
/*
* On saving/restoring host sve state, always use the maximum VL for
* the host. The layout of the data when saving the sve state depends
* on the VL, so use a consistent (i.e., the maximum) host VL.
*
* Setting ZCR_EL2 to ZCR_ELx_LEN_MASK sets the effective length
* supported by the system (or limited at EL3).
*/
write_sysreg_s(ZCR_ELx_LEN_MASK, SYS_ZCR_EL2);
__sve_restore_state(sve_state->sve_regs + sve_ffr_offset(kvm_host_sve_max_vl),
&sve_state->fpsr,
true);
write_sysreg_el1(sve_state->zcr_el1, SYS_ZCR);
}
static void fpsimd_sve_flush(void)
{
*host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED;
}
static void fpsimd_sve_sync(struct kvm_vcpu *vcpu)
{
if (!guest_owns_fp_regs())
return;
cpacr_clear_set(0, CPACR_ELx_FPEN | CPACR_ELx_ZEN);
isb();
if (vcpu_has_sve(vcpu))
__hyp_sve_save_guest(vcpu);
else
__fpsimd_save_state(&vcpu->arch.ctxt.fp_regs);
if (system_supports_sve())
__hyp_sve_restore_host();
else
__fpsimd_restore_state(*host_data_ptr(fpsimd_state));
*host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED;
}
static void flush_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
{
struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
fpsimd_sve_flush();
hyp_vcpu->vcpu.arch.ctxt = host_vcpu->arch.ctxt;
hyp_vcpu->vcpu.arch.sve_state = kern_hyp_va(host_vcpu->arch.sve_state);
/* Limit guest vector length to the maximum supported by the host. */
hyp_vcpu->vcpu.arch.sve_max_vl = min(host_vcpu->arch.sve_max_vl, kvm_host_sve_max_vl);
hyp_vcpu->vcpu.arch.hw_mmu = host_vcpu->arch.hw_mmu;
hyp_vcpu->vcpu.arch.hcr_el2 = host_vcpu->arch.hcr_el2;
hyp_vcpu->vcpu.arch.mdcr_el2 = host_vcpu->arch.mdcr_el2;
hyp_vcpu->vcpu.arch.iflags = host_vcpu->arch.iflags;
hyp_vcpu->vcpu.arch.debug_ptr = kern_hyp_va(host_vcpu->arch.debug_ptr);
hyp_vcpu->vcpu.arch.vsesr_el2 = host_vcpu->arch.vsesr_el2;
hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3 = host_vcpu->arch.vgic_cpu.vgic_v3;
}
static void sync_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
{
struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
struct vgic_v3_cpu_if *hyp_cpu_if = &hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3;
struct vgic_v3_cpu_if *host_cpu_if = &host_vcpu->arch.vgic_cpu.vgic_v3;
unsigned int i;
fpsimd_sve_sync(&hyp_vcpu->vcpu);
host_vcpu->arch.ctxt = hyp_vcpu->vcpu.arch.ctxt;
host_vcpu->arch.hcr_el2 = hyp_vcpu->vcpu.arch.hcr_el2;
host_vcpu->arch.fault = hyp_vcpu->vcpu.arch.fault;
host_vcpu->arch.iflags = hyp_vcpu->vcpu.arch.iflags;
host_cpu_if->vgic_hcr = hyp_cpu_if->vgic_hcr;
for (i = 0; i < hyp_cpu_if->used_lrs; ++i)
host_cpu_if->vgic_lr[i] = hyp_cpu_if->vgic_lr[i];
}
static void handle___kvm_vcpu_run(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 1);
int ret;
host_vcpu = kern_hyp_va(host_vcpu);
if (unlikely(is_protected_kvm_enabled())) {
struct pkvm_hyp_vcpu *hyp_vcpu;
struct kvm *host_kvm;
/*
* KVM (and pKVM) doesn't support SME guests for now, and
* ensures that SME features aren't enabled in pstate when
* loading a vcpu. Therefore, if SME features enabled the host
* is misbehaving.
*/
if (unlikely(system_supports_sme() && read_sysreg_s(SYS_SVCR))) {
ret = -EINVAL;
goto out;
}
host_kvm = kern_hyp_va(host_vcpu->kvm);
hyp_vcpu = pkvm_load_hyp_vcpu(host_kvm->arch.pkvm.handle,
host_vcpu->vcpu_idx);
if (!hyp_vcpu) {
ret = -EINVAL;
goto out;
}
flush_hyp_vcpu(hyp_vcpu);
ret = __kvm_vcpu_run(&hyp_vcpu->vcpu);
sync_hyp_vcpu(hyp_vcpu);
pkvm_put_hyp_vcpu(hyp_vcpu);
} else {
/* The host is fully trusted, run its vCPU directly. */
ret = __kvm_vcpu_run(host_vcpu);
}
out:
cpu_reg(host_ctxt, 1) = ret;
}
static void handle___kvm_adjust_pc(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1);
__kvm_adjust_pc(kern_hyp_va(vcpu));
}
static void handle___kvm_flush_vm_context(struct kvm_cpu_context *host_ctxt)
{
__kvm_flush_vm_context();
}
static void handle___kvm_tlb_flush_vmid_ipa(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2);
DECLARE_REG(int, level, host_ctxt, 3);
__kvm_tlb_flush_vmid_ipa(kern_hyp_va(mmu), ipa, level);
}
static void handle___kvm_tlb_flush_vmid_ipa_nsh(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2);
DECLARE_REG(int, level, host_ctxt, 3);
__kvm_tlb_flush_vmid_ipa_nsh(kern_hyp_va(mmu), ipa, level);
}
static void
handle___kvm_tlb_flush_vmid_range(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
DECLARE_REG(phys_addr_t, start, host_ctxt, 2);
DECLARE_REG(unsigned long, pages, host_ctxt, 3);
__kvm_tlb_flush_vmid_range(kern_hyp_va(mmu), start, pages);
}
static void handle___kvm_tlb_flush_vmid(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
__kvm_tlb_flush_vmid(kern_hyp_va(mmu));
}
static void handle___kvm_flush_cpu_context(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
__kvm_flush_cpu_context(kern_hyp_va(mmu));
}
static void handle___kvm_timer_set_cntvoff(struct kvm_cpu_context *host_ctxt)
{
__kvm_timer_set_cntvoff(cpu_reg(host_ctxt, 1));
}
static void handle___kvm_enable_ssbs(struct kvm_cpu_context *host_ctxt)
{
u64 tmp;
tmp = read_sysreg_el2(SYS_SCTLR);
tmp |= SCTLR_ELx_DSSBS;
write_sysreg_el2(tmp, SYS_SCTLR);
}
static void handle___vgic_v3_get_gic_config(struct kvm_cpu_context *host_ctxt)
{
cpu_reg(host_ctxt, 1) = __vgic_v3_get_gic_config();
}
static void handle___vgic_v3_init_lrs(struct kvm_cpu_context *host_ctxt)
{
__vgic_v3_init_lrs();
}
static void handle___kvm_get_mdcr_el2(struct kvm_cpu_context *host_ctxt)
{
cpu_reg(host_ctxt, 1) = __kvm_get_mdcr_el2();
}
static void handle___vgic_v3_save_vmcr_aprs(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1);
__vgic_v3_save_vmcr_aprs(kern_hyp_va(cpu_if));
}
static void handle___vgic_v3_restore_vmcr_aprs(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1);
__vgic_v3_restore_vmcr_aprs(kern_hyp_va(cpu_if));
}
static void handle___pkvm_init(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(phys_addr_t, phys, host_ctxt, 1);
DECLARE_REG(unsigned long, size, host_ctxt, 2);
DECLARE_REG(unsigned long, nr_cpus, host_ctxt, 3);
DECLARE_REG(unsigned long *, per_cpu_base, host_ctxt, 4);
DECLARE_REG(u32, hyp_va_bits, host_ctxt, 5);
/*
* __pkvm_init() will return only if an error occurred, otherwise it
* will tail-call in __pkvm_init_finalise() which will have to deal
* with the host context directly.
*/
cpu_reg(host_ctxt, 1) = __pkvm_init(phys, size, nr_cpus, per_cpu_base,
hyp_va_bits);
}
static void handle___pkvm_cpu_set_vector(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(enum arm64_hyp_spectre_vector, slot, host_ctxt, 1);
cpu_reg(host_ctxt, 1) = pkvm_cpu_set_vector(slot);
}
static void handle___pkvm_host_share_hyp(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(u64, pfn, host_ctxt, 1);
cpu_reg(host_ctxt, 1) = __pkvm_host_share_hyp(pfn);
}
static void handle___pkvm_host_unshare_hyp(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(u64, pfn, host_ctxt, 1);
cpu_reg(host_ctxt, 1) = __pkvm_host_unshare_hyp(pfn);
}
static void handle___pkvm_create_private_mapping(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(phys_addr_t, phys, host_ctxt, 1);
DECLARE_REG(size_t, size, host_ctxt, 2);
DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 3);
/*
* __pkvm_create_private_mapping() populates a pointer with the
* hypervisor start address of the allocation.
*
* However, handle___pkvm_create_private_mapping() hypercall crosses the
* EL1/EL2 boundary so the pointer would not be valid in this context.
*
* Instead pass the allocation address as the return value (or return
* ERR_PTR() on failure).
*/
unsigned long haddr;
int err = __pkvm_create_private_mapping(phys, size, prot, &haddr);
if (err)
haddr = (unsigned long)ERR_PTR(err);
cpu_reg(host_ctxt, 1) = haddr;
}
static void handle___pkvm_prot_finalize(struct kvm_cpu_context *host_ctxt)
{
cpu_reg(host_ctxt, 1) = __pkvm_prot_finalize();
}
static void handle___pkvm_vcpu_init_traps(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1);
__pkvm_vcpu_init_traps(kern_hyp_va(vcpu));
}
static void handle___pkvm_init_vm(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(struct kvm *, host_kvm, host_ctxt, 1);
DECLARE_REG(unsigned long, vm_hva, host_ctxt, 2);
DECLARE_REG(unsigned long, pgd_hva, host_ctxt, 3);
host_kvm = kern_hyp_va(host_kvm);
cpu_reg(host_ctxt, 1) = __pkvm_init_vm(host_kvm, vm_hva, pgd_hva);
}
static void handle___pkvm_init_vcpu(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 2);
DECLARE_REG(unsigned long, vcpu_hva, host_ctxt, 3);
host_vcpu = kern_hyp_va(host_vcpu);
cpu_reg(host_ctxt, 1) = __pkvm_init_vcpu(handle, host_vcpu, vcpu_hva);
}
static void handle___pkvm_teardown_vm(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
cpu_reg(host_ctxt, 1) = __pkvm_teardown_vm(handle);
}
typedef void (*hcall_t)(struct kvm_cpu_context *);
#define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x
static const hcall_t host_hcall[] = {
/* ___kvm_hyp_init */
HANDLE_FUNC(__kvm_get_mdcr_el2),
HANDLE_FUNC(__pkvm_init),
HANDLE_FUNC(__pkvm_create_private_mapping),
HANDLE_FUNC(__pkvm_cpu_set_vector),
HANDLE_FUNC(__kvm_enable_ssbs),
HANDLE_FUNC(__vgic_v3_init_lrs),
HANDLE_FUNC(__vgic_v3_get_gic_config),
HANDLE_FUNC(__pkvm_prot_finalize),
HANDLE_FUNC(__pkvm_host_share_hyp),
HANDLE_FUNC(__pkvm_host_unshare_hyp),
HANDLE_FUNC(__kvm_adjust_pc),
HANDLE_FUNC(__kvm_vcpu_run),
HANDLE_FUNC(__kvm_flush_vm_context),
HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa),
HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa_nsh),
HANDLE_FUNC(__kvm_tlb_flush_vmid),
HANDLE_FUNC(__kvm_tlb_flush_vmid_range),
HANDLE_FUNC(__kvm_flush_cpu_context),
HANDLE_FUNC(__kvm_timer_set_cntvoff),
HANDLE_FUNC(__vgic_v3_save_vmcr_aprs),
HANDLE_FUNC(__vgic_v3_restore_vmcr_aprs),
HANDLE_FUNC(__pkvm_vcpu_init_traps),
HANDLE_FUNC(__pkvm_init_vm),
HANDLE_FUNC(__pkvm_init_vcpu),
HANDLE_FUNC(__pkvm_teardown_vm),
};
static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(unsigned long, id, host_ctxt, 0);
unsigned long hcall_min = 0;
hcall_t hfn;
/*
* If pKVM has been initialised then reject any calls to the
* early "privileged" hypercalls. Note that we cannot reject
* calls to __pkvm_prot_finalize for two reasons: (1) The static
* key used to determine initialisation must be toggled prior to
* finalisation and (2) finalisation is performed on a per-CPU
* basis. This is all fine, however, since __pkvm_prot_finalize
* returns -EPERM after the first call for a given CPU.
*/
if (static_branch_unlikely(&kvm_protected_mode_initialized))
hcall_min = __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize;
id &= ~ARM_SMCCC_CALL_HINTS;
id -= KVM_HOST_SMCCC_ID(0);
if (unlikely(id < hcall_min || id >= ARRAY_SIZE(host_hcall)))
goto inval;
hfn = host_hcall[id];
if (unlikely(!hfn))
goto inval;
cpu_reg(host_ctxt, 0) = SMCCC_RET_SUCCESS;
hfn(host_ctxt);
return;
inval:
cpu_reg(host_ctxt, 0) = SMCCC_RET_NOT_SUPPORTED;
}
static void default_host_smc_handler(struct kvm_cpu_context *host_ctxt)
{
__kvm_hyp_host_forward_smc(host_ctxt);
}
static void handle_host_smc(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(u64, func_id, host_ctxt, 0);
bool handled;
func_id &= ~ARM_SMCCC_CALL_HINTS;
handled = kvm_host_psci_handler(host_ctxt, func_id);
if (!handled)
handled = kvm_host_ffa_handler(host_ctxt, func_id);
if (!handled)
default_host_smc_handler(host_ctxt);
/* SMC was trapped, move ELR past the current PC. */
kvm_skip_host_instr();
}
void handle_trap(struct kvm_cpu_context *host_ctxt)
{
u64 esr = read_sysreg_el2(SYS_ESR);
switch (ESR_ELx_EC(esr)) {
case ESR_ELx_EC_HVC64:
handle_host_hcall(host_ctxt);
break;
case ESR_ELx_EC_SMC64:
handle_host_smc(host_ctxt);
break;
case ESR_ELx_EC_SVE:
cpacr_clear_set(0, CPACR_ELx_ZEN);
isb();
sve_cond_update_zcr_vq(ZCR_ELx_LEN_MASK, SYS_ZCR_EL2);
break;
case ESR_ELx_EC_IABT_LOW:
case ESR_ELx_EC_DABT_LOW:
handle_host_mem_abort(host_ctxt);
break;
default:
BUG();
}
}
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