diff options
Diffstat (limited to 'arch/arm64/kvm/hyp/tlb.c')
| -rw-r--r-- | arch/arm64/kvm/hyp/tlb.c | 242 |
1 files changed, 0 insertions, 242 deletions
diff --git a/arch/arm64/kvm/hyp/tlb.c b/arch/arm64/kvm/hyp/tlb.c deleted file mode 100644 index d063a576d511..000000000000 --- a/arch/arm64/kvm/hyp/tlb.c +++ /dev/null @@ -1,242 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright (C) 2015 - ARM Ltd - * Author: Marc Zyngier <marc.zyngier@arm.com> - */ - -#include <linux/irqflags.h> - -#include <asm/kvm_hyp.h> -#include <asm/kvm_mmu.h> -#include <asm/tlbflush.h> - -struct tlb_inv_context { - unsigned long flags; - u64 tcr; - u64 sctlr; -}; - -static void __hyp_text __tlb_switch_to_guest_vhe(struct kvm *kvm, - struct tlb_inv_context *cxt) -{ - u64 val; - - local_irq_save(cxt->flags); - - if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { - /* - * For CPUs that are affected by ARM errata 1165522 or 1530923, - * we cannot trust stage-1 to be in a correct state at that - * point. Since we do not want to force a full load of the - * vcpu state, we prevent the EL1 page-table walker to - * allocate new TLBs. This is done by setting the EPD bits - * in the TCR_EL1 register. We also need to prevent it to - * allocate IPA->PA walks, so we enable the S1 MMU... - */ - val = cxt->tcr = read_sysreg_el1(SYS_TCR); - val |= TCR_EPD1_MASK | TCR_EPD0_MASK; - write_sysreg_el1(val, SYS_TCR); - val = cxt->sctlr = read_sysreg_el1(SYS_SCTLR); - val |= SCTLR_ELx_M; - write_sysreg_el1(val, SYS_SCTLR); - } - - /* - * With VHE enabled, we have HCR_EL2.{E2H,TGE} = {1,1}, and - * most TLB operations target EL2/EL0. In order to affect the - * guest TLBs (EL1/EL0), we need to change one of these two - * bits. Changing E2H is impossible (goodbye TTBR1_EL2), so - * let's flip TGE before executing the TLB operation. - * - * ARM erratum 1165522 requires some special handling (again), - * as we need to make sure both stages of translation are in - * place before clearing TGE. __load_guest_stage2() already - * has an ISB in order to deal with this. - */ - __load_guest_stage2(kvm); - val = read_sysreg(hcr_el2); - val &= ~HCR_TGE; - write_sysreg(val, hcr_el2); - isb(); -} - -static void __hyp_text __tlb_switch_to_guest_nvhe(struct kvm *kvm, - struct tlb_inv_context *cxt) -{ - 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. - */ - val = cxt->tcr = read_sysreg_el1(SYS_TCR); - val |= TCR_EPD1_MASK | TCR_EPD0_MASK; - write_sysreg_el1(val, SYS_TCR); - isb(); - } - - /* __load_guest_stage2() includes an ISB for the workaround. */ - __load_guest_stage2(kvm); - asm(ALTERNATIVE("isb", "nop", ARM64_WORKAROUND_SPECULATIVE_AT)); -} - -static void __hyp_text __tlb_switch_to_guest(struct kvm *kvm, - struct tlb_inv_context *cxt) -{ - if (has_vhe()) - __tlb_switch_to_guest_vhe(kvm, cxt); - else - __tlb_switch_to_guest_nvhe(kvm, cxt); -} - -static void __hyp_text __tlb_switch_to_host_vhe(struct kvm *kvm, - struct tlb_inv_context *cxt) -{ - /* - * We're done with the TLB operation, let's restore the host's - * view of HCR_EL2. - */ - write_sysreg(0, vttbr_el2); - write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2); - isb(); - - if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { - /* Restore the registers to what they were */ - write_sysreg_el1(cxt->tcr, SYS_TCR); - write_sysreg_el1(cxt->sctlr, SYS_SCTLR); - } - - local_irq_restore(cxt->flags); -} - -static void __hyp_text __tlb_switch_to_host_nvhe(struct kvm *kvm, - struct tlb_inv_context *cxt) -{ - write_sysreg(0, vttbr_el2); - - if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { - /* Ensure write of the host VMID */ - isb(); - /* Restore the host's TCR_EL1 */ - write_sysreg_el1(cxt->tcr, SYS_TCR); - } -} - -static void __hyp_text __tlb_switch_to_host(struct kvm *kvm, - struct tlb_inv_context *cxt) -{ - if (has_vhe()) - __tlb_switch_to_host_vhe(kvm, cxt); - else - __tlb_switch_to_host_nvhe(kvm, cxt); -} - -void __hyp_text __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa) -{ - struct tlb_inv_context cxt; - - dsb(ishst); - - /* Switch to requested VMID */ - kvm = kern_hyp_va(kvm); - __tlb_switch_to_guest(kvm, &cxt); - - /* - * We could do so much better if we had the VA as well. - * Instead, we invalidate Stage-2 for this IPA, and the - * whole of Stage-1. Weep... - */ - ipa >>= 12; - __tlbi(ipas2e1is, ipa); - - /* - * We have to ensure completion of the invalidation at Stage-2, - * since a table walk on another CPU could refill a TLB with a - * complete (S1 + S2) walk based on the old Stage-2 mapping if - * the Stage-1 invalidation happened first. - */ - dsb(ish); - __tlbi(vmalle1is); - dsb(ish); - isb(); - - /* - * If the host is running at EL1 and we have a VPIPT I-cache, - * then we must perform I-cache maintenance at EL2 in order for - * it to have an effect on the guest. Since the guest cannot hit - * I-cache lines allocated with a different VMID, we don't need - * to worry about junk out of guest reset (we nuke the I-cache on - * VMID rollover), but we do need to be careful when remapping - * executable pages for the same guest. This can happen when KSM - * takes a CoW fault on an executable page, copies the page into - * a page that was previously mapped in the guest and then needs - * to invalidate the guest view of the I-cache for that page - * from EL1. To solve this, we invalidate the entire I-cache when - * unmapping a page from a guest if we have a VPIPT I-cache but - * the host is running at EL1. As above, we could do better if - * we had the VA. - * - * The moral of this story is: if you have a VPIPT I-cache, then - * you should be running with VHE enabled. - */ - if (!has_vhe() && icache_is_vpipt()) - __flush_icache_all(); - - __tlb_switch_to_host(kvm, &cxt); -} - -void __hyp_text __kvm_tlb_flush_vmid(struct kvm *kvm) -{ - struct tlb_inv_context cxt; - - dsb(ishst); - - /* Switch to requested VMID */ - kvm = kern_hyp_va(kvm); - __tlb_switch_to_guest(kvm, &cxt); - - __tlbi(vmalls12e1is); - dsb(ish); - isb(); - - __tlb_switch_to_host(kvm, &cxt); -} - -void __hyp_text __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu) -{ - struct kvm *kvm = kern_hyp_va(kern_hyp_va(vcpu)->kvm); - struct tlb_inv_context cxt; - - /* Switch to requested VMID */ - __tlb_switch_to_guest(kvm, &cxt); - - __tlbi(vmalle1); - dsb(nsh); - isb(); - - __tlb_switch_to_host(kvm, &cxt); -} - -void __hyp_text __kvm_flush_vm_context(void) -{ - dsb(ishst); - __tlbi(alle1is); - - /* - * VIPT and PIPT caches are not affected by VMID, so no maintenance - * is necessary across a VMID rollover. - * - * VPIPT caches constrain lookup and maintenance to the active VMID, - * so we need to invalidate lines with a stale VMID to avoid an ABA - * race after multiple rollovers. - * - */ - if (icache_is_vpipt()) - asm volatile("ic ialluis"); - - dsb(ish); -} |