This patch is part of a series which builds KVM's non-VHE hyp code separately from VHE and the rest of the kernel. tlb.c contains code for flushing the TLB, with parts shared between VHE/nVHE. These common routines are moved into a header file tlb.h, VHE-specific code remains in tlb.c and nVHE-specific code is moved to nvhe/tlb.c. The header file expects its users to implement two helper functions declared at the top of the file. Signed-off-by: David Brazdil <dbrazdil@xxxxxxxxxx> --- arch/arm64/kernel/image-vars.h | 8 +- arch/arm64/kvm/hyp/nvhe/Makefile | 2 +- arch/arm64/kvm/hyp/nvhe/tlb.c | 69 +++++++++++++ arch/arm64/kvm/hyp/tlb.c | 170 +++---------------------------- arch/arm64/kvm/hyp/tlb.h | 129 +++++++++++++++++++++++ 5 files changed, 216 insertions(+), 162 deletions(-) create mode 100644 arch/arm64/kvm/hyp/nvhe/tlb.c create mode 100644 arch/arm64/kvm/hyp/tlb.h diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h index 59c53566eceb..c0a0ec238854 100644 --- a/arch/arm64/kernel/image-vars.h +++ b/arch/arm64/kernel/image-vars.h @@ -62,14 +62,11 @@ __efistub__ctype = _ctype; */ __hyp_text___guest_exit = __guest_exit; +__hyp_text___icache_flags = __icache_flags; __hyp_text___kvm_enable_ssbs = __kvm_enable_ssbs; -__hyp_text___kvm_flush_vm_context = __kvm_flush_vm_context; __hyp_text___kvm_get_mdcr_el2 = __kvm_get_mdcr_el2; __hyp_text___kvm_handle_stub_hvc = __kvm_handle_stub_hvc; __hyp_text___kvm_timer_set_cntvoff = __kvm_timer_set_cntvoff; -__hyp_text___kvm_tlb_flush_local_vmid = __kvm_tlb_flush_local_vmid; -__hyp_text___kvm_tlb_flush_vmid = __kvm_tlb_flush_vmid; -__hyp_text___kvm_tlb_flush_vmid_ipa = __kvm_tlb_flush_vmid_ipa; __hyp_text___kvm_vcpu_run_nvhe = __kvm_vcpu_run_nvhe; __hyp_text___vgic_v3_get_ich_vtr_el2 = __vgic_v3_get_ich_vtr_el2; __hyp_text___vgic_v3_init_lrs = __vgic_v3_init_lrs; @@ -79,8 +76,11 @@ __hyp_text___vgic_v3_save_aprs = __vgic_v3_save_aprs; __hyp_text___vgic_v3_write_vmcr = __vgic_v3_write_vmcr; __hyp_text_abort_guest_exit_end = abort_guest_exit_end; __hyp_text_abort_guest_exit_start = abort_guest_exit_start; +__hyp_text_arm64_const_caps_ready = arm64_const_caps_ready; __hyp_text_arm64_enable_wa2_handling = arm64_enable_wa2_handling; __hyp_text_arm64_ssbd_callback_required = arm64_ssbd_callback_required; +__hyp_text_cpu_hwcap_keys = cpu_hwcap_keys; +__hyp_text_cpu_hwcaps = cpu_hwcaps; __hyp_text_hyp_panic = hyp_panic; __hyp_text_kimage_voffset = kimage_voffset; __hyp_text_kvm_host_data = kvm_host_data; diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index fa20b2723652..0da836cb5580 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -7,7 +7,7 @@ asflags-y := -D__HYPERVISOR__ ccflags-y := -D__HYPERVISOR__ -fno-stack-protector -DDISABLE_BRANCH_PROFILING \ $(DISABLE_STACKLEAK_PLUGIN) -obj-y := host_hypercall.o ../hyp-entry.o +obj-y := tlb.o host_hypercall.o ../hyp-entry.o obj-y := $(patsubst %.o,%.hyp.o,$(obj-y)) extra-y := $(patsubst %.hyp.o,%.hyp.tmp.o,$(obj-y)) diff --git a/arch/arm64/kvm/hyp/nvhe/tlb.c b/arch/arm64/kvm/hyp/nvhe/tlb.c new file mode 100644 index 000000000000..1b8f4000f98c --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/tlb.c @@ -0,0 +1,69 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2015 - ARM Ltd + * Author: Marc Zyngier <marc.zyngier@xxxxxxx> + */ + +#include <linux/irqflags.h> + +#include <asm/kvm_hyp.h> +#include <asm/kvm_mmu.h> +#include <asm/tlbflush.h> + +#include "../tlb.h" + +static void __hyp_text __tlb_switch_to_guest(struct kvm *kvm, + struct tlb_inv_context *cxt) +{ + if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) { + 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(kvm); + isb(); +} + +static void __hyp_text __tlb_switch_to_host(struct kvm *kvm, + struct tlb_inv_context *cxt) +{ + write_sysreg(0, vttbr_el2); + + if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) { + /* Ensure write of the host VMID */ + isb(); + /* Restore the host's TCR_EL1 */ + write_sysreg_el1(cxt->tcr, SYS_TCR); + } +} + +void __hyp_text __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa) +{ + __tlb_flush_vmid_ipa(kvm, ipa); +} + +void __hyp_text __kvm_tlb_flush_vmid(struct kvm *kvm) +{ + __tlb_flush_vmid(kvm); +} + +void __hyp_text __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu) +{ + __tlb_flush_local_vmid(vcpu); +} + +void __hyp_text __kvm_flush_vm_context(void) +{ + __tlb_flush_vm_context(); +} diff --git a/arch/arm64/kvm/hyp/tlb.c b/arch/arm64/kvm/hyp/tlb.c index ceaddbe4279f..ab55b0c4a80c 100644 --- a/arch/arm64/kvm/hyp/tlb.c +++ b/arch/arm64/kvm/hyp/tlb.c @@ -10,14 +10,10 @@ #include <asm/kvm_mmu.h> #include <asm/tlbflush.h> -struct tlb_inv_context { - unsigned long flags; - u64 tcr; - u64 sctlr; -}; +#include "tlb.h" -static void __hyp_text __tlb_switch_to_guest_vhe(struct kvm *kvm, - struct tlb_inv_context *cxt) +static void __hyp_text __tlb_switch_to_guest(struct kvm *kvm, + struct tlb_inv_context *cxt) { u64 val; @@ -60,40 +56,8 @@ static void __hyp_text __tlb_switch_to_guest_vhe(struct kvm *kvm, 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_NVHE)) { - 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(kvm); - isb(); -} - -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) +static void __hyp_text __tlb_switch_to_host(struct kvm *kvm, + struct tlb_inv_context *cxt) { /* * We're done with the TLB operation, let's restore the host's @@ -112,130 +76,22 @@ static void __hyp_text __tlb_switch_to_host_vhe(struct kvm *kvm, local_irq_restore(cxt->flags); } -static void __hyp_text __tlb_switch_to_host_nvhe(struct kvm *kvm, - struct tlb_inv_context *cxt) +void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa) { - write_sysreg(0, vttbr_el2); - - if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) { - /* Ensure write of the host VMID */ - isb(); - /* Restore the host's TCR_EL1 */ - write_sysreg_el1(cxt->tcr, SYS_TCR); - } + __tlb_flush_vmid_ipa(kvm, ipa); } -static void __hyp_text __tlb_switch_to_host(struct kvm *kvm, - struct tlb_inv_context *cxt) +void __kvm_tlb_flush_vmid(struct kvm *kvm) { - if (has_vhe()) - __tlb_switch_to_host_vhe(kvm, cxt); - else - __tlb_switch_to_host_nvhe(kvm, cxt); + __tlb_flush_vmid(kvm); } -void __hyp_text __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa) +void __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu) { - 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); + __tlb_flush_local_vmid(vcpu); } -void __hyp_text __kvm_tlb_flush_vmid(struct kvm *kvm) +void __kvm_flush_vm_context(void) { - 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); + __tlb_flush_vm_context(); } diff --git a/arch/arm64/kvm/hyp/tlb.h b/arch/arm64/kvm/hyp/tlb.h new file mode 100644 index 000000000000..f62ed96cb896 --- /dev/null +++ b/arch/arm64/kvm/hyp/tlb.h @@ -0,0 +1,129 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2015 - ARM Ltd + * Author: Marc Zyngier <marc.zyngier@xxxxxxx> + */ + +#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(struct kvm *kvm, + struct tlb_inv_context *cxt); +static void __hyp_text __tlb_switch_to_host(struct kvm *kvm, + struct tlb_inv_context *cxt); + +static inline void __hyp_text +__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); +} + +static inline void __hyp_text __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); +} + +static inline void __hyp_text __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); +} + +static inline void __hyp_text __tlb_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); +} -- 2.26.1 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm