On 09/02/16 18:42, Christoffer Dall wrote: > On Thu, Feb 04, 2016 at 11:00:25AM +0000, Marc Zyngier wrote: >> Convert the TLB invalidation code to C, hooking it into the >> build system whilst we're at it. >> >> Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> >> --- >> arch/arm/kvm/Makefile | 1 + >> arch/arm/kvm/hyp/Makefile | 5 ++++ >> arch/arm/kvm/hyp/hyp.h | 5 ++++ >> arch/arm/kvm/hyp/tlb.c | 71 +++++++++++++++++++++++++++++++++++++++++++++++ >> 4 files changed, 82 insertions(+) >> create mode 100644 arch/arm/kvm/hyp/Makefile >> create mode 100644 arch/arm/kvm/hyp/tlb.c >> >> diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile >> index c5eef02c..eb1bf43 100644 >> --- a/arch/arm/kvm/Makefile >> +++ b/arch/arm/kvm/Makefile >> @@ -17,6 +17,7 @@ AFLAGS_interrupts.o := -Wa,-march=armv7-a$(plus_virt) >> KVM := ../../../virt/kvm >> kvm-arm-y = $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o $(KVM)/vfio.o >> >> +obj-$(CONFIG_KVM_ARM_HOST) += hyp/ >> obj-y += kvm-arm.o init.o interrupts.o >> obj-y += arm.o handle_exit.o guest.o mmu.o emulate.o reset.o >> obj-y += coproc.o coproc_a15.o coproc_a7.o mmio.o psci.o perf.o >> diff --git a/arch/arm/kvm/hyp/Makefile b/arch/arm/kvm/hyp/Makefile >> new file mode 100644 >> index 0000000..36c760d >> --- /dev/null >> +++ b/arch/arm/kvm/hyp/Makefile >> @@ -0,0 +1,5 @@ >> +# >> +# Makefile for Kernel-based Virtual Machine module, HYP part >> +# >> + >> +obj-$(CONFIG_KVM_ARM_HOST) += tlb.o >> diff --git a/arch/arm/kvm/hyp/hyp.h b/arch/arm/kvm/hyp/hyp.h >> index 727089f..5808bbd 100644 >> --- a/arch/arm/kvm/hyp/hyp.h >> +++ b/arch/arm/kvm/hyp/hyp.h >> @@ -42,4 +42,9 @@ >> }) >> #define read_sysreg(...) __read_sysreg(__VA_ARGS__) >> >> +#define VTTBR __ACCESS_CP15_64(6, c2) >> +#define ICIALLUIS __ACCESS_CP15(c7, 0, c1, 0) >> +#define TLBIALLIS __ACCESS_CP15(c8, 0, c3, 0) >> +#define TLBIALLNSNHIS __ACCESS_CP15(c8, 4, c3, 4) >> + >> #endif /* __ARM_KVM_HYP_H__ */ >> diff --git a/arch/arm/kvm/hyp/tlb.c b/arch/arm/kvm/hyp/tlb.c >> new file mode 100644 >> index 0000000..993fe89 >> --- /dev/null >> +++ b/arch/arm/kvm/hyp/tlb.c >> @@ -0,0 +1,71 @@ >> +/* >> + * Original code: >> + * Copyright (C) 2012 - Virtual Open Systems and Columbia University >> + * Author: Christoffer Dall <c.dall@xxxxxxxxxxxxxxxxxxxxxx> >> + * >> + * Mostly rewritten in C by Marc Zyngier <marc.zyngier@xxxxxxx> >> + * >> + * This program is free software; you can redistribute it and/or modify >> + * it under the terms of the GNU General Public License version 2 as >> + * published by the Free Software Foundation. >> + * >> + * This program is distributed in the hope that it will be useful, >> + * but WITHOUT ANY WARRANTY; without even the implied warranty of >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >> + * GNU General Public License for more details. >> + * >> + * You should have received a copy of the GNU General Public License >> + * along with this program. If not, see <http://www.gnu.org/licenses/>. >> + */ >> + >> +#include "hyp.h" >> + >> +/** >> + * Flush per-VMID TLBs >> + * >> + * __kvm_tlb_flush_vmid(struct kvm *kvm); >> + * >> + * We rely on the hardware to broadcast the TLB invalidation to all CPUs >> + * inside the inner-shareable domain (which is the case for all v7 >> + * implementations). If we come across a non-IS SMP implementation, we'll >> + * have to use an IPI based mechanism. Until then, we stick to the simple >> + * hardware assisted version. >> + * >> + * As v7 does not support flushing per IPA, just nuke the whole TLB >> + * instead, ignoring the ipa value. >> + */ >> +static void __hyp_text __tlb_flush_vmid(struct kvm *kvm) >> +{ >> + dsb(ishst); >> + >> + /* Switch to requested VMID */ >> + kvm = kern_hyp_va(kvm); >> + write_sysreg(kvm->arch.vttbr, VTTBR); >> + isb(); >> + >> + write_sysreg(0, TLBIALLIS); >> + dsb(ish); >> + isb(); >> + >> + write_sysreg(0, VTTBR); >> +} >> + >> +__alias(__tlb_flush_vmid) void __weak __kvm_tlb_flush_vmid(struct kvm *kvm); >> + >> +static void __hyp_text __tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa) >> +{ >> + __tlb_flush_vmid(kvm); >> +} >> + >> +__alias(__tlb_flush_vmid_ipa) void __weak __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, >> + phys_addr_t ipa); >> + >> +static void __hyp_text __tlb_flush_vm_context(void) >> +{ >> + dsb(ishst); > > do we need this initial dsb? I'm a copy-paste muppet. I'll drop that. >> + write_sysreg(0, TLBIALLNSNHIS); >> + write_sysreg(0, ICIALLUIS); >> + dsb(ish); > > we used to have an isb here, but we got rid of this because it's always > followed by eret? Indeed. We were super extra cautious in the old code, and eret does the right thing. Thanks, M. -- Jazz is not dead. It just smells funny... -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
