diff options
Diffstat (limited to 'arch/arm64/kvm/hyp/nvhe/tlb.c')
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/tlb.c | 115 |
1 files changed, 91 insertions, 24 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/tlb.c b/arch/arm64/kvm/hyp/nvhe/tlb.c index 2fc68da403..ca3c09df8d 100644 --- a/arch/arm64/kvm/hyp/nvhe/tlb.c +++ b/arch/arm64/kvm/hyp/nvhe/tlb.c @@ -11,13 +11,23 @@ #include <nvhe/mem_protect.h> struct tlb_inv_context { - u64 tcr; + struct kvm_s2_mmu *mmu; + u64 tcr; + u64 sctlr; }; -static void __tlb_switch_to_guest(struct kvm_s2_mmu *mmu, - struct tlb_inv_context *cxt, - bool nsh) +static void enter_vmid_context(struct kvm_s2_mmu *mmu, + struct tlb_inv_context *cxt, + bool nsh) { + struct kvm_s2_mmu *host_s2_mmu = &host_mmu.arch.mmu; + struct kvm_cpu_context *host_ctxt; + struct kvm_vcpu *vcpu; + + host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt; + vcpu = host_ctxt->__hyp_running_vcpu; + cxt->mmu = NULL; + /* * We have two requirements: * @@ -40,20 +50,55 @@ static void __tlb_switch_to_guest(struct kvm_s2_mmu *mmu, else dsb(ish); + /* + * If we're already in the desired context, then there's nothing to do. + */ + if (vcpu) { + /* + * We're in guest context. However, for this to work, this needs + * to be called from within __kvm_vcpu_run(), which ensures that + * __hyp_running_vcpu is set to the current guest vcpu. + */ + if (mmu == vcpu->arch.hw_mmu || WARN_ON(mmu != host_s2_mmu)) + return; + + cxt->mmu = vcpu->arch.hw_mmu; + } else { + /* We're in host context. */ + if (mmu == host_s2_mmu) + return; + + cxt->mmu = host_s2_mmu; + } + if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { u64 val; /* * For CPUs that are affected by ARM 1319367, we need to - * avoid a host Stage-1 walk while we have the guest's - * VMID set in the VTTBR in order to invalidate TLBs. - * We're guaranteed that the S1 MMU is enabled, so we can - * simply set the EPD bits to avoid any further TLB fill. + * avoid a Stage-1 walk with the old VMID while we have + * the new VMID set in the VTTBR in order to invalidate TLBs. + * We're guaranteed that the host S1 MMU is enabled, so + * we can simply set the EPD bits to avoid any further + * TLB fill. For guests, we ensure that the S1 MMU is + * temporarily enabled in the next context. */ val = cxt->tcr = read_sysreg_el1(SYS_TCR); val |= TCR_EPD1_MASK | TCR_EPD0_MASK; write_sysreg_el1(val, SYS_TCR); isb(); + + if (vcpu) { + val = cxt->sctlr = read_sysreg_el1(SYS_SCTLR); + if (!(val & SCTLR_ELx_M)) { + val |= SCTLR_ELx_M; + write_sysreg_el1(val, SYS_SCTLR); + isb(); + } + } else { + /* The host S1 MMU is always enabled. */ + cxt->sctlr = SCTLR_ELx_M; + } } /* @@ -62,18 +107,40 @@ static void __tlb_switch_to_guest(struct kvm_s2_mmu *mmu, * ensuring that we always have an ISB, but not two ISBs back * to back. */ - __load_stage2(mmu, kern_hyp_va(mmu->arch)); + if (vcpu) + __load_host_stage2(); + else + __load_stage2(mmu, kern_hyp_va(mmu->arch)); + asm(ALTERNATIVE("isb", "nop", ARM64_WORKAROUND_SPECULATIVE_AT)); } -static void __tlb_switch_to_host(struct tlb_inv_context *cxt) +static void exit_vmid_context(struct tlb_inv_context *cxt) { - __load_host_stage2(); + struct kvm_s2_mmu *mmu = cxt->mmu; + struct kvm_cpu_context *host_ctxt; + struct kvm_vcpu *vcpu; + + host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt; + vcpu = host_ctxt->__hyp_running_vcpu; + + if (!mmu) + return; + + if (vcpu) + __load_stage2(mmu, kern_hyp_va(mmu->arch)); + else + __load_host_stage2(); if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { - /* Ensure write of the host VMID */ + /* Ensure write of the old VMID */ isb(); - /* Restore the host's TCR_EL1 */ + + if (!(cxt->sctlr & SCTLR_ELx_M)) { + write_sysreg_el1(cxt->sctlr, SYS_SCTLR); + isb(); + } + write_sysreg_el1(cxt->tcr, SYS_TCR); } } @@ -84,7 +151,7 @@ void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, struct tlb_inv_context cxt; /* Switch to requested VMID */ - __tlb_switch_to_guest(mmu, &cxt, false); + enter_vmid_context(mmu, &cxt, false); /* * We could do so much better if we had the VA as well. @@ -105,7 +172,7 @@ void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, dsb(ish); isb(); - __tlb_switch_to_host(&cxt); + exit_vmid_context(&cxt); } void __kvm_tlb_flush_vmid_ipa_nsh(struct kvm_s2_mmu *mmu, @@ -114,7 +181,7 @@ void __kvm_tlb_flush_vmid_ipa_nsh(struct kvm_s2_mmu *mmu, struct tlb_inv_context cxt; /* Switch to requested VMID */ - __tlb_switch_to_guest(mmu, &cxt, true); + enter_vmid_context(mmu, &cxt, true); /* * We could do so much better if we had the VA as well. @@ -135,7 +202,7 @@ void __kvm_tlb_flush_vmid_ipa_nsh(struct kvm_s2_mmu *mmu, dsb(nsh); isb(); - __tlb_switch_to_host(&cxt); + exit_vmid_context(&cxt); } void __kvm_tlb_flush_vmid_range(struct kvm_s2_mmu *mmu, @@ -152,7 +219,7 @@ void __kvm_tlb_flush_vmid_range(struct kvm_s2_mmu *mmu, start = round_down(start, stride); /* Switch to requested VMID */ - __tlb_switch_to_guest(mmu, &cxt, false); + enter_vmid_context(mmu, &cxt, false); __flush_s2_tlb_range_op(ipas2e1is, start, pages, stride, TLBI_TTL_UNKNOWN); @@ -162,7 +229,7 @@ void __kvm_tlb_flush_vmid_range(struct kvm_s2_mmu *mmu, dsb(ish); isb(); - __tlb_switch_to_host(&cxt); + exit_vmid_context(&cxt); } void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu) @@ -170,13 +237,13 @@ void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu) struct tlb_inv_context cxt; /* Switch to requested VMID */ - __tlb_switch_to_guest(mmu, &cxt, false); + enter_vmid_context(mmu, &cxt, false); __tlbi(vmalls12e1is); dsb(ish); isb(); - __tlb_switch_to_host(&cxt); + exit_vmid_context(&cxt); } void __kvm_flush_cpu_context(struct kvm_s2_mmu *mmu) @@ -184,19 +251,19 @@ void __kvm_flush_cpu_context(struct kvm_s2_mmu *mmu) struct tlb_inv_context cxt; /* Switch to requested VMID */ - __tlb_switch_to_guest(mmu, &cxt, false); + enter_vmid_context(mmu, &cxt, false); __tlbi(vmalle1); asm volatile("ic iallu"); dsb(nsh); isb(); - __tlb_switch_to_host(&cxt); + exit_vmid_context(&cxt); } void __kvm_flush_vm_context(void) { - /* Same remark as in __tlb_switch_to_guest() */ + /* Same remark as in enter_vmid_context() */ dsb(ish); __tlbi(alle1is); dsb(ish); |