All of lore.kernel.org
 help / color / mirror / Atom feed
From: Marc Zyngier <maz@kernel.org>
To: kvmarm@lists.linux.dev, kvm@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org
Cc: Alexandru Elisei <alexandru.elisei@arm.com>,
	Andre Przywara <andre.przywara@arm.com>,
	Chase Conklin <chase.conklin@arm.com>,
	Christoffer Dall <christoffer.dall@arm.com>,
	Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>,
	Jintack Lim <jintack@cs.columbia.edu>,
	Russell King <rmk+kernel@armlinux.org.uk>,
	James Morse <james.morse@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Oliver Upton <oliver.upton@linux.dev>,
	Zenghui Yu <yuzenghui@huawei.com>
Subject: [PATCH v8 42/69] KVM: arm64: nv: Trap and emulate TLBI instructions from virtual EL2
Date: Tue, 31 Jan 2023 09:24:37 +0000	[thread overview]
Message-ID: <20230131092504.2880505-43-maz@kernel.org> (raw)
In-Reply-To: <20230131092504.2880505-1-maz@kernel.org>

From: Jintack Lim <jintack.lim@linaro.org>

When supporting nested virtualization a guest hypervisor executing TLBI
instructions must be trapped and emulated by the host hypervisor,
because the guest hypervisor can only affect physical TLB entries
relating to its own execution environment (virtual EL2 in EL1) but not
to the nested guests as required by the semantics of the instructions
and TLBI instructions might also result in updates (invalidations) to
shadow page tables.

This patch does several things.

1. List and define all TLBI system instructions to emulate.

2. Emulate TLBI ALLE2(IS) instruction executed in the virtual EL2. Since
we emulate the virtual EL2 in the EL1, we invalidate EL1&0 regime stage
1 TLB entries with setting vttbr_el2 having the VMID of the virtual EL2.

3. Emulate TLBI VAE2* instruction executed in the virtual EL2. Based on the
same principle as TLBI ALLE2 instruction, we can simply emulate those
instructions by executing corresponding VAE1* instructions with the
virtual EL2's VMID assigned by the host hypervisor.

Note that we are able to emulate TLBI ALLE2IS precisely by only
invalidating stage 1 TLB entries via TLBI VMALL1IS instruction, but to
make it simeple, we reuse the existing function, __kvm_tlb_flush_vmid(),
which invalidates both of stage 1 and 2 TLB entries.

4. TLBI ALLE1(IS) instruction invalidates all EL1&0 regime stage 1 and 2
TLB entries (on all PEs in the same Inner Shareable domain). To emulate
these instructions, we first need to clear all the mappings in the
shadow page tables since executing those instructions implies the change
of mappings in the stage 2 page tables maintained by the guest
hypervisor.  We then need to invalidate all EL1&0 regime stage 1 and 2
TLB entries of all VMIDs, which are assigned by the host hypervisor, for
this VM.

5. Based on the same principle as TLBI ALLE1(IS) emulation, we clear the
mappings in the shadow stage-2 page tables and invalidate TLB entries.
But this time we do it only for the current VMID from the guest
hypervisor's perspective, not for all VMIDs.

6. Based on the same principle as TLBI ALLE1(IS) and TLBI VMALLS12E1(IS)
emulation, we clear the mappings in the shadow stage-2 page tables and
invalidate TLB entries. We do it only for one mapping for the current
VMID from the guest hypervisor's view.

7. Forward system instruction traps to the virtual EL2 if a
corresponding bit in the virtual HCR_EL2 is set.

8. Even though a guest hypervisor can execute TLBI instructions that are
accesible at EL1 without trap, it's wrong; All those TLBI instructions
work based on current VMID, and when running a guest hypervisor current
VMID is the one for itself, not the one from the virtual vttbr_el2. So
letting a guest hypervisor execute those TLBI instructions results in
invalidating its own TLB entries and leaving invalid TLB entries
unhandled.

Therefore we trap and emulate those TLBI instructions. The emulation is
simple; we find a shadow VMID mapped to the virtual vttbr_el2, set it in
the physical vttbr_el2, then execute the same instruction in EL2.

We don't set HCR_EL2.TTLB bit yet.

  [ Changes performed by Marc Zynger:

    The TLBI handling code more or less directly execute the same
    instruction that has been trapped (with an EL2->EL1 conversion
    in the case of an EL2 TLBI), but that's unfortunately not enough:

    - TLBIs must be upgraded to the Inner Shareable domain to account
      for vcpu migration, just like we already have with HCR_EL2.FB.

    - The DSB instruction that synchronises these must thus be on
      the Inner Shareable domain as well.

    - Prior to executing the TLBI, we need another DSB ISHST to make
      sure that the update to the page tables is now visible.

      Ordering of system instructions fixed

    - The current TLB invalidation code is pretty buggy, as it assume a
      page mapping. On the contrary, it is likely that TLB invalidation
      will cover more than a single page, and the size should be decided
      by the guests configuration (and not the host's).

      Since we don't cache the guest mapping sizes in the shadow PT yet,
      let's assume the worse case (a block mapping) and invalidate that.

      Take this opportunity to fix the decoding of the parameter (it
      isn't a straight IPA).

    - In general, we always emulate local TBL invalidations as being
      as upgraded to the Inner Shareable domain so that we can easily
      deal with vcpu migration. This is consistent with the fact that
      we set HCR_EL2.FB when running non-nested VMs.

      So let's emulate TLBI ALLE2 as ALLE2IS.
  ]

  [ Changes performed by Christoffer Dall:

    Sometimes when we are invalidating the TLB for a certain S2 MMU
    context, this context can also have EL2 context associated with it
    and we have to invalidate this too.
  ]

Signed-off-by: Jintack Lim <jintack.lim@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/include/asm/kvm_asm.h |   2 +
 arch/arm64/include/asm/sysreg.h  |  36 +++++
 arch/arm64/kvm/hyp/vhe/switch.c  |   8 +-
 arch/arm64/kvm/hyp/vhe/tlb.c     |  81 +++++++++++
 arch/arm64/kvm/mmu.c             |  17 ++-
 arch/arm64/kvm/sys_regs.c        | 227 +++++++++++++++++++++++++++++++
 6 files changed, 366 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index 373558ea24d8..d73f8d5a8a25 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -226,6 +226,8 @@ extern void __kvm_flush_cpu_context(struct kvm_s2_mmu *mmu);
 extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa,
 				     int level);
 extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu);
+extern void __kvm_tlb_vae2is(struct kvm_s2_mmu *mmu, u64 va, u64 sys_encoding);
+extern void __kvm_tlb_el1_instr(struct kvm_s2_mmu *mmu, u64 val, u64 sys_encoding);
 
 extern void __kvm_timer_set_cntvoff(u64 cntvoff);
 extern void __kvm_at_s1e01(struct kvm_vcpu *vcpu, u32 op, u64 vaddr);
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 9c718f4af944..35147f369336 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -624,6 +624,42 @@
 #define OP_AT_S12E0R	sys_insn(AT_Op0, 4, AT_CRn, 8, 6)
 #define OP_AT_S12E0W	sys_insn(AT_Op0, 4, AT_CRn, 8, 7)
 
+/* TLBI instructions */
+#define TLBI_Op0	1
+#define TLBI_Op1_EL1	0	/* Accessible from EL1 or higher */
+#define TLBI_Op1_EL2	4	/* Accessible from EL2 or higher */
+#define TLBI_CRn	8
+#define tlbi_insn_el1(CRm, Op2)	sys_insn(TLBI_Op0, TLBI_Op1_EL1, TLBI_CRn, (CRm), (Op2))
+#define tlbi_insn_el2(CRm, Op2)	sys_insn(TLBI_Op0, TLBI_Op1_EL2, TLBI_CRn, (CRm), (Op2))
+
+#define OP_TLBI_VMALLE1IS	tlbi_insn_el1(3, 0)
+#define OP_TLBI_VAE1IS		tlbi_insn_el1(3, 1)
+#define OP_TLBI_ASIDE1IS	tlbi_insn_el1(3, 2)
+#define OP_TLBI_VAAE1IS		tlbi_insn_el1(3, 3)
+#define OP_TLBI_VALE1IS		tlbi_insn_el1(3, 5)
+#define OP_TLBI_VAALE1IS	tlbi_insn_el1(3, 7)
+#define OP_TLBI_VMALLE1		tlbi_insn_el1(7, 0)
+#define OP_TLBI_VAE1		tlbi_insn_el1(7, 1)
+#define OP_TLBI_ASIDE1		tlbi_insn_el1(7, 2)
+#define OP_TLBI_VAAE1		tlbi_insn_el1(7, 3)
+#define OP_TLBI_VALE1		tlbi_insn_el1(7, 5)
+#define OP_TLBI_VAALE1		tlbi_insn_el1(7, 7)
+
+#define OP_TLBI_IPAS2E1IS	tlbi_insn_el2(0, 1)
+#define OP_TLBI_IPAS2LE1IS	tlbi_insn_el2(0, 5)
+#define OP_TLBI_ALLE2IS		tlbi_insn_el2(3, 0)
+#define OP_TLBI_VAE2IS		tlbi_insn_el2(3, 1)
+#define OP_TLBI_ALLE1IS		tlbi_insn_el2(3, 4)
+#define OP_TLBI_VALE2IS		tlbi_insn_el2(3, 5)
+#define OP_TLBI_VMALLS12E1IS	tlbi_insn_el2(3, 6)
+#define OP_TLBI_IPAS2E1		tlbi_insn_el2(4, 1)
+#define OP_TLBI_IPAS2LE1	tlbi_insn_el2(4, 5)
+#define OP_TLBI_ALLE2		tlbi_insn_el2(7, 0)
+#define OP_TLBI_VAE2		tlbi_insn_el2(7, 1)
+#define OP_TLBI_ALLE1		tlbi_insn_el2(7, 4)
+#define OP_TLBI_VALE2		tlbi_insn_el2(7, 5)
+#define OP_TLBI_VMALLS12E1	tlbi_insn_el2(7, 6)
+
 /* Common SCTLR_ELx flags. */
 #define SCTLR_ELx_ENTP2	(BIT(60))
 #define SCTLR_ELx_DSSBS	(BIT(44))
diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c
index 6d186a3e5e5f..a17bf261d501 100644
--- a/arch/arm64/kvm/hyp/vhe/switch.c
+++ b/arch/arm64/kvm/hyp/vhe/switch.c
@@ -47,7 +47,7 @@ static void __activate_traps(struct kvm_vcpu *vcpu)
 			 * the EL1 virtual memory control register accesses
 			 * as well as the AT S1 operations.
 			 */
-			hcr |= HCR_TVM | HCR_TRVM | HCR_AT | HCR_NV1;
+			hcr |= HCR_TVM | HCR_TRVM | HCR_AT | HCR_TTLB | HCR_NV1;
 		} else {
 			/*
 			 * For a guest hypervisor on v8.1 (VHE), allow to
@@ -75,11 +75,11 @@ static void __activate_traps(struct kvm_vcpu *vcpu)
 
 			/*
 			 * If we're using the EL1 translation regime
-			 * (TGE clear), then ensure that AT S1 ops are
-			 * trapped too.
+			 * (TGE clear), then ensure that AT S1 and
+			 * TLBI E1 ops are trapped too.
 			 */
 			if (!vcpu_el2_tge_is_set(vcpu))
-				hcr |= HCR_AT;
+				hcr |= HCR_AT | HCR_TTLB;
 		}
 	}
 
diff --git a/arch/arm64/kvm/hyp/vhe/tlb.c b/arch/arm64/kvm/hyp/vhe/tlb.c
index 24cef9b87f9e..c4389db4cc22 100644
--- a/arch/arm64/kvm/hyp/vhe/tlb.c
+++ b/arch/arm64/kvm/hyp/vhe/tlb.c
@@ -161,3 +161,84 @@ void __kvm_flush_vm_context(void)
 
 	dsb(ish);
 }
+
+void __kvm_tlb_vae2is(struct kvm_s2_mmu *mmu, u64 va, u64 sys_encoding)
+{
+	struct tlb_inv_context cxt;
+
+	dsb(ishst);
+
+	/* Switch to requested VMID */
+	__tlb_switch_to_guest(mmu, &cxt);
+
+	/*
+	 * Execute the EL1 version of TLBI VAE2* instruction, forcing
+	 * an upgrade to the Inner Shareable domain in order to
+	 * perform the invalidation on all CPUs.
+	 */
+	switch (sys_encoding) {
+	case OP_TLBI_VAE2:
+	case OP_TLBI_VAE2IS:
+		__tlbi(vae1is, va);
+		break;
+	case OP_TLBI_VALE2:
+	case OP_TLBI_VALE2IS:
+		__tlbi(vale1is, va);
+		break;
+	default:
+		break;
+	}
+	dsb(ish);
+	isb();
+
+	__tlb_switch_to_host(&cxt);
+}
+
+void __kvm_tlb_el1_instr(struct kvm_s2_mmu *mmu, u64 val, u64 sys_encoding)
+{
+	struct tlb_inv_context cxt;
+
+	dsb(ishst);
+
+	/* Switch to requested VMID */
+	__tlb_switch_to_guest(mmu, &cxt);
+
+	/*
+	 * Execute the same instruction as the guest hypervisor did,
+	 * expanding the scope of local TLB invalidations to the Inner
+	 * Shareable domain so that it takes place on all CPUs. This
+	 * is equivalent to having HCR_EL2.FB set.
+	 */
+	switch (sys_encoding) {
+	case OP_TLBI_VMALLE1:
+	case OP_TLBI_VMALLE1IS:
+		__tlbi(vmalle1is);
+		break;
+	case OP_TLBI_VAE1:
+	case OP_TLBI_VAE1IS:
+		__tlbi(vae1is, val);
+		break;
+	case OP_TLBI_ASIDE1:
+	case OP_TLBI_ASIDE1IS:
+		__tlbi(aside1is, val);
+		break;
+	case OP_TLBI_VAAE1:
+	case OP_TLBI_VAAE1IS:
+		__tlbi(vaae1is, val);
+		break;
+	case OP_TLBI_VALE1:
+	case OP_TLBI_VALE1IS:
+		__tlbi(vale1is, val);
+		break;
+	case OP_TLBI_VAALE1:
+	case OP_TLBI_VAALE1IS:
+		__tlbi(vaale1is, val);
+		break;
+	default:
+		break;
+	}
+	dsb(ish);
+	isb();
+
+	__tlb_switch_to_host(&cxt);
+}
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 6dc82b0384ce..4680a703847b 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -89,7 +89,22 @@ static bool memslot_is_logging(struct kvm_memory_slot *memslot)
 void kvm_flush_remote_tlbs(struct kvm *kvm)
 {
 	++kvm->stat.generic.remote_tlb_flush_requests;
-	kvm_call_hyp(__kvm_tlb_flush_vmid, &kvm->arch.mmu);
+
+	if (!kvm->arch.nested_mmus) {
+		/*
+		 * For a normal (i.e. non-nested) guest, flush entries for the
+		 * given VMID.
+		 */
+		kvm_call_hyp(__kvm_tlb_flush_vmid, &kvm->arch.mmu);
+	} else {
+		/*
+		 * When supporting nested virtualization, we can have multiple
+		 * VMIDs in play for each VCPU in the VM, so it's really not
+		 * worth it to try to quiesce the system and flush all the
+		 * VMIDs that may be in use, instead just nuke the whole thing.
+		 */
+		kvm_call_hyp(__kvm_flush_vm_context);
+	}
 }
 
 static bool kvm_is_device_pfn(unsigned long pfn)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 66a379baf8c7..40215710ede2 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -2603,6 +2603,205 @@ static bool handle_s12w(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 	return handle_s12(vcpu, p, r, true);
 }
 
+static bool handle_alle2is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			   const struct sys_reg_desc *r)
+{
+	if (vcpu_has_nv(vcpu) && forward_nv_traps(vcpu))
+		return false;
+
+	/*
+	 * To emulate invalidating all EL2 regime stage 1 TLB entries for all
+	 * PEs, executing TLBI VMALLE1IS is enough. But reuse the existing
+	 * interface for the simplicity; invalidating stage 2 entries doesn't
+	 * affect the correctness.
+	 */
+	__kvm_tlb_flush_vmid(&vcpu->kvm->arch.mmu);
+	return true;
+}
+
+static bool handle_vae2is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			  const struct sys_reg_desc *r)
+{
+	int sys_encoding = sys_insn(p->Op0, p->Op1, p->CRn, p->CRm, p->Op2);
+
+	if (vcpu_has_nv(vcpu) && forward_nv_traps(vcpu))
+		return false;
+
+	/*
+	 * Based on the same principle as TLBI ALLE2 instruction
+	 * emulation, we emulate TLBI VAE2* instructions by executing
+	 * corresponding TLBI VAE1* instructions with the virtual
+	 * EL2's VMID assigned by the host hypervisor.
+	 */
+	__kvm_tlb_vae2is(&vcpu->kvm->arch.mmu, p->regval, sys_encoding);
+	return true;
+}
+
+static bool handle_alle1is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			   const struct sys_reg_desc *r)
+{
+	struct kvm_s2_mmu *mmu = &vcpu->kvm->arch.mmu;
+
+	if (vcpu_has_nv(vcpu) && forward_nv_traps(vcpu))
+		return false;
+
+	write_lock(&vcpu->kvm->mmu_lock);
+
+	/*
+	 * Clear all mappings in the shadow page tables and invalidate the stage
+	 * 1 and 2 TLB entries via kvm_tlb_flush_vmid_ipa().
+	 */
+	kvm_nested_s2_unmap(vcpu->kvm);
+
+	if (atomic64_read(&mmu->vmid.id)) {
+		/*
+		 * Invalidate the stage 1 and 2 TLB entries for the host OS
+		 * in a VM only if there is one.
+		 */
+		__kvm_tlb_flush_vmid(mmu);
+	}
+
+	write_unlock(&vcpu->kvm->mmu_lock);
+
+	return true;
+}
+
+static bool handle_vmalls12e1is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+				const struct sys_reg_desc *r)
+{
+	struct kvm_s2_mmu *mmu;
+	u64 vttbr;
+
+	if (vcpu_has_nv(vcpu) && forward_nv_traps(vcpu))
+		return false;
+
+	vttbr = vcpu_read_sys_reg(vcpu, VTTBR_EL2);
+	write_lock(&vcpu->kvm->mmu_lock);
+
+	mmu = lookup_s2_mmu(vcpu->kvm, vttbr, HCR_VM);
+	if (mmu)
+		kvm_unmap_stage2_range(mmu, 0, kvm_phys_size(vcpu->kvm));
+
+	mmu = lookup_s2_mmu(vcpu->kvm, vttbr, 0);
+	if (mmu)
+		kvm_unmap_stage2_range(mmu, 0, kvm_phys_size(vcpu->kvm));
+
+	write_unlock(&vcpu->kvm->mmu_lock);
+
+	return true;
+}
+
+static bool handle_ipas2e1is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			     const struct sys_reg_desc *r)
+{
+	u64 vttbr = vcpu_read_sys_reg(vcpu, VTTBR_EL2);
+	u64 vtcr = vcpu_read_sys_reg(vcpu, VTCR_EL2);
+	struct kvm_s2_mmu *mmu;
+	u64 base_addr;
+	int max_size;
+
+	if (vcpu_has_nv(vcpu) && forward_nv_traps(vcpu))
+		return false;
+
+	/*
+	 * We drop a number of things from the supplied value:
+	 *
+	 * - NS bit: we're non-secure only.
+	 *
+	 * - TTL field: We already have the granule size from the
+	 *   VTCR_EL2.TG0 field, and the level is only relevant to the
+	 *   guest's S2PT.
+	 *
+	 * - IPA[51:48]: We don't support 52bit IPA just yet...
+	 *
+	 * And of course, adjust the IPA to be on an actual address.
+	 */
+	base_addr = (p->regval & GENMASK_ULL(35, 0)) << 12;
+
+	/* Compute the maximum extent of the invalidation */
+	switch ((vtcr & VTCR_EL2_TG0_MASK)) {
+	case VTCR_EL2_TG0_4K:
+		max_size = SZ_1G;
+		break;
+	case VTCR_EL2_TG0_16K:
+		max_size = SZ_32M;
+		break;
+	case VTCR_EL2_TG0_64K:
+		/*
+		 * No, we do not support 52bit IPA in nested yet. Once
+		 * we do, this should be 4TB.
+		 */
+		/* FIXME: remove the 52bit PA support from the IDregs */
+		max_size = SZ_512M;
+		break;
+	default:
+		BUG();
+	}
+
+	write_lock(&vcpu->kvm->mmu_lock);
+
+	mmu = lookup_s2_mmu(vcpu->kvm, vttbr, HCR_VM);
+	if (mmu)
+		kvm_unmap_stage2_range(mmu, base_addr, max_size);
+
+	mmu = lookup_s2_mmu(vcpu->kvm, vttbr, 0);
+	if (mmu)
+		kvm_unmap_stage2_range(mmu, base_addr, max_size);
+
+	write_unlock(&vcpu->kvm->mmu_lock);
+
+	return true;
+}
+
+static bool handle_tlbi_el1(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			    const struct sys_reg_desc *r)
+{
+	u32 sys_encoding = sys_insn(p->Op0, p->Op1, p->CRn, p->CRm, p->Op2);
+
+	if (vcpu_has_nv(vcpu) && forward_traps(vcpu, HCR_TTLB))
+		return false;
+
+	/*
+	 * If we're here, this is because we've trapped on a EL1 TLBI
+	 * instruction that affects the EL1 translation regime while
+	 * we're running in a context that doesn't allow us to let the
+	 * HW do its thing (aka vEL2):
+	 *
+	 * - HCR_EL2.E2H == 0 : a non-VHE guest
+	 * - HCR_EL2.{E2H,TGE} == { 1, 0 } : a VHE guest in guest mode
+	 *
+	 * We don't expect these helpers to ever be called when running
+	 * in a vEL1 context.
+	 */
+
+	WARN_ON(!vcpu_is_el2(vcpu));
+
+	mutex_lock(&vcpu->kvm->lock);
+
+	if ((__vcpu_sys_reg(vcpu, HCR_EL2) & (HCR_E2H | HCR_TGE)) != (HCR_E2H | HCR_TGE)) {
+		u64 virtual_vttbr = vcpu_read_sys_reg(vcpu, VTTBR_EL2);
+		struct kvm_s2_mmu *mmu;
+
+		mmu = lookup_s2_mmu(vcpu->kvm, virtual_vttbr, HCR_VM);
+		if (mmu)
+			__kvm_tlb_el1_instr(mmu, p->regval, sys_encoding);
+
+		mmu = lookup_s2_mmu(vcpu->kvm, virtual_vttbr, 0);
+		if (mmu)
+			__kvm_tlb_el1_instr(mmu, p->regval, sys_encoding);
+	} else {
+		/*
+		 * ARMv8.4-NV allows the guest to change TGE behind
+		 * our back, so we always trap EL1 TLBIs from vEL2...
+		 */
+		__kvm_tlb_el1_instr(&vcpu->kvm->arch.mmu, p->regval, sys_encoding);
+	}
+
+	mutex_unlock(&vcpu->kvm->lock);
+
+	return true;
+}
+
 /*
  * AT instruction emulation
  *
@@ -2688,12 +2887,40 @@ static struct sys_reg_desc sys_insn_descs[] = {
 	{ SYS_DESC(SYS_DC_CSW), access_dcsw },
 	{ SYS_DESC(SYS_DC_CISW), access_dcsw },
 
+	SYS_INSN(TLBI_VMALLE1IS, handle_tlbi_el1),
+	SYS_INSN(TLBI_VAE1IS, handle_tlbi_el1),
+	SYS_INSN(TLBI_ASIDE1IS, handle_tlbi_el1),
+	SYS_INSN(TLBI_VAAE1IS, handle_tlbi_el1),
+	SYS_INSN(TLBI_VALE1IS, handle_tlbi_el1),
+	SYS_INSN(TLBI_VAALE1IS, handle_tlbi_el1),
+	SYS_INSN(TLBI_VMALLE1, handle_tlbi_el1),
+	SYS_INSN(TLBI_VAE1, handle_tlbi_el1),
+	SYS_INSN(TLBI_ASIDE1, handle_tlbi_el1),
+	SYS_INSN(TLBI_VAAE1, handle_tlbi_el1),
+	SYS_INSN(TLBI_VALE1, handle_tlbi_el1),
+	SYS_INSN(TLBI_VAALE1, handle_tlbi_el1),
+
 	SYS_INSN(AT_S1E2R, handle_s1e2),
 	SYS_INSN(AT_S1E2W, handle_s1e2),
 	SYS_INSN(AT_S12E1R, handle_s12r),
 	SYS_INSN(AT_S12E1W, handle_s12w),
 	SYS_INSN(AT_S12E0R, handle_s12r),
 	SYS_INSN(AT_S12E0W, handle_s12w),
+
+	SYS_INSN(TLBI_IPAS2E1IS, handle_ipas2e1is),
+	SYS_INSN(TLBI_IPAS2LE1IS, handle_ipas2e1is),
+	SYS_INSN(TLBI_ALLE2IS, handle_alle2is),
+	SYS_INSN(TLBI_VAE2IS, handle_vae2is),
+	SYS_INSN(TLBI_ALLE1IS, handle_alle1is),
+	SYS_INSN(TLBI_VALE2IS, handle_vae2is),
+	SYS_INSN(TLBI_VMALLS12E1IS, handle_vmalls12e1is),
+	SYS_INSN(TLBI_IPAS2E1, handle_ipas2e1is),
+	SYS_INSN(TLBI_IPAS2LE1, handle_ipas2e1is),
+	SYS_INSN(TLBI_ALLE2, handle_alle2is),
+	SYS_INSN(TLBI_VAE2, handle_vae2is),
+	SYS_INSN(TLBI_ALLE1, handle_alle1is),
+	SYS_INSN(TLBI_VALE2, handle_vae2is),
+	SYS_INSN(TLBI_VMALLS12E1, handle_vmalls12e1is),
 };
 
 static bool trap_dbgdidr(struct kvm_vcpu *vcpu,
-- 
2.34.1


WARNING: multiple messages have this Message-ID (diff)
From: Marc Zyngier <maz@kernel.org>
To: kvmarm@lists.linux.dev, kvm@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org
Cc: Alexandru Elisei <alexandru.elisei@arm.com>,
	Andre Przywara <andre.przywara@arm.com>,
	Chase Conklin <chase.conklin@arm.com>,
	Christoffer Dall <christoffer.dall@arm.com>,
	Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>,
	Jintack Lim <jintack@cs.columbia.edu>,
	Russell King <rmk+kernel@armlinux.org.uk>,
	James Morse <james.morse@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Oliver Upton <oliver.upton@linux.dev>,
	Zenghui Yu <yuzenghui@huawei.com>
Subject: [PATCH v8 42/69] KVM: arm64: nv: Trap and emulate TLBI instructions from virtual EL2
Date: Tue, 31 Jan 2023 09:24:37 +0000	[thread overview]
Message-ID: <20230131092504.2880505-43-maz@kernel.org> (raw)
In-Reply-To: <20230131092504.2880505-1-maz@kernel.org>

From: Jintack Lim <jintack.lim@linaro.org>

When supporting nested virtualization a guest hypervisor executing TLBI
instructions must be trapped and emulated by the host hypervisor,
because the guest hypervisor can only affect physical TLB entries
relating to its own execution environment (virtual EL2 in EL1) but not
to the nested guests as required by the semantics of the instructions
and TLBI instructions might also result in updates (invalidations) to
shadow page tables.

This patch does several things.

1. List and define all TLBI system instructions to emulate.

2. Emulate TLBI ALLE2(IS) instruction executed in the virtual EL2. Since
we emulate the virtual EL2 in the EL1, we invalidate EL1&0 regime stage
1 TLB entries with setting vttbr_el2 having the VMID of the virtual EL2.

3. Emulate TLBI VAE2* instruction executed in the virtual EL2. Based on the
same principle as TLBI ALLE2 instruction, we can simply emulate those
instructions by executing corresponding VAE1* instructions with the
virtual EL2's VMID assigned by the host hypervisor.

Note that we are able to emulate TLBI ALLE2IS precisely by only
invalidating stage 1 TLB entries via TLBI VMALL1IS instruction, but to
make it simeple, we reuse the existing function, __kvm_tlb_flush_vmid(),
which invalidates both of stage 1 and 2 TLB entries.

4. TLBI ALLE1(IS) instruction invalidates all EL1&0 regime stage 1 and 2
TLB entries (on all PEs in the same Inner Shareable domain). To emulate
these instructions, we first need to clear all the mappings in the
shadow page tables since executing those instructions implies the change
of mappings in the stage 2 page tables maintained by the guest
hypervisor.  We then need to invalidate all EL1&0 regime stage 1 and 2
TLB entries of all VMIDs, which are assigned by the host hypervisor, for
this VM.

5. Based on the same principle as TLBI ALLE1(IS) emulation, we clear the
mappings in the shadow stage-2 page tables and invalidate TLB entries.
But this time we do it only for the current VMID from the guest
hypervisor's perspective, not for all VMIDs.

6. Based on the same principle as TLBI ALLE1(IS) and TLBI VMALLS12E1(IS)
emulation, we clear the mappings in the shadow stage-2 page tables and
invalidate TLB entries. We do it only for one mapping for the current
VMID from the guest hypervisor's view.

7. Forward system instruction traps to the virtual EL2 if a
corresponding bit in the virtual HCR_EL2 is set.

8. Even though a guest hypervisor can execute TLBI instructions that are
accesible at EL1 without trap, it's wrong; All those TLBI instructions
work based on current VMID, and when running a guest hypervisor current
VMID is the one for itself, not the one from the virtual vttbr_el2. So
letting a guest hypervisor execute those TLBI instructions results in
invalidating its own TLB entries and leaving invalid TLB entries
unhandled.

Therefore we trap and emulate those TLBI instructions. The emulation is
simple; we find a shadow VMID mapped to the virtual vttbr_el2, set it in
the physical vttbr_el2, then execute the same instruction in EL2.

We don't set HCR_EL2.TTLB bit yet.

  [ Changes performed by Marc Zynger:

    The TLBI handling code more or less directly execute the same
    instruction that has been trapped (with an EL2->EL1 conversion
    in the case of an EL2 TLBI), but that's unfortunately not enough:

    - TLBIs must be upgraded to the Inner Shareable domain to account
      for vcpu migration, just like we already have with HCR_EL2.FB.

    - The DSB instruction that synchronises these must thus be on
      the Inner Shareable domain as well.

    - Prior to executing the TLBI, we need another DSB ISHST to make
      sure that the update to the page tables is now visible.

      Ordering of system instructions fixed

    - The current TLB invalidation code is pretty buggy, as it assume a
      page mapping. On the contrary, it is likely that TLB invalidation
      will cover more than a single page, and the size should be decided
      by the guests configuration (and not the host's).

      Since we don't cache the guest mapping sizes in the shadow PT yet,
      let's assume the worse case (a block mapping) and invalidate that.

      Take this opportunity to fix the decoding of the parameter (it
      isn't a straight IPA).

    - In general, we always emulate local TBL invalidations as being
      as upgraded to the Inner Shareable domain so that we can easily
      deal with vcpu migration. This is consistent with the fact that
      we set HCR_EL2.FB when running non-nested VMs.

      So let's emulate TLBI ALLE2 as ALLE2IS.
  ]

  [ Changes performed by Christoffer Dall:

    Sometimes when we are invalidating the TLB for a certain S2 MMU
    context, this context can also have EL2 context associated with it
    and we have to invalidate this too.
  ]

Signed-off-by: Jintack Lim <jintack.lim@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/include/asm/kvm_asm.h |   2 +
 arch/arm64/include/asm/sysreg.h  |  36 +++++
 arch/arm64/kvm/hyp/vhe/switch.c  |   8 +-
 arch/arm64/kvm/hyp/vhe/tlb.c     |  81 +++++++++++
 arch/arm64/kvm/mmu.c             |  17 ++-
 arch/arm64/kvm/sys_regs.c        | 227 +++++++++++++++++++++++++++++++
 6 files changed, 366 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index 373558ea24d8..d73f8d5a8a25 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -226,6 +226,8 @@ extern void __kvm_flush_cpu_context(struct kvm_s2_mmu *mmu);
 extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa,
 				     int level);
 extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu);
+extern void __kvm_tlb_vae2is(struct kvm_s2_mmu *mmu, u64 va, u64 sys_encoding);
+extern void __kvm_tlb_el1_instr(struct kvm_s2_mmu *mmu, u64 val, u64 sys_encoding);
 
 extern void __kvm_timer_set_cntvoff(u64 cntvoff);
 extern void __kvm_at_s1e01(struct kvm_vcpu *vcpu, u32 op, u64 vaddr);
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 9c718f4af944..35147f369336 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -624,6 +624,42 @@
 #define OP_AT_S12E0R	sys_insn(AT_Op0, 4, AT_CRn, 8, 6)
 #define OP_AT_S12E0W	sys_insn(AT_Op0, 4, AT_CRn, 8, 7)
 
+/* TLBI instructions */
+#define TLBI_Op0	1
+#define TLBI_Op1_EL1	0	/* Accessible from EL1 or higher */
+#define TLBI_Op1_EL2	4	/* Accessible from EL2 or higher */
+#define TLBI_CRn	8
+#define tlbi_insn_el1(CRm, Op2)	sys_insn(TLBI_Op0, TLBI_Op1_EL1, TLBI_CRn, (CRm), (Op2))
+#define tlbi_insn_el2(CRm, Op2)	sys_insn(TLBI_Op0, TLBI_Op1_EL2, TLBI_CRn, (CRm), (Op2))
+
+#define OP_TLBI_VMALLE1IS	tlbi_insn_el1(3, 0)
+#define OP_TLBI_VAE1IS		tlbi_insn_el1(3, 1)
+#define OP_TLBI_ASIDE1IS	tlbi_insn_el1(3, 2)
+#define OP_TLBI_VAAE1IS		tlbi_insn_el1(3, 3)
+#define OP_TLBI_VALE1IS		tlbi_insn_el1(3, 5)
+#define OP_TLBI_VAALE1IS	tlbi_insn_el1(3, 7)
+#define OP_TLBI_VMALLE1		tlbi_insn_el1(7, 0)
+#define OP_TLBI_VAE1		tlbi_insn_el1(7, 1)
+#define OP_TLBI_ASIDE1		tlbi_insn_el1(7, 2)
+#define OP_TLBI_VAAE1		tlbi_insn_el1(7, 3)
+#define OP_TLBI_VALE1		tlbi_insn_el1(7, 5)
+#define OP_TLBI_VAALE1		tlbi_insn_el1(7, 7)
+
+#define OP_TLBI_IPAS2E1IS	tlbi_insn_el2(0, 1)
+#define OP_TLBI_IPAS2LE1IS	tlbi_insn_el2(0, 5)
+#define OP_TLBI_ALLE2IS		tlbi_insn_el2(3, 0)
+#define OP_TLBI_VAE2IS		tlbi_insn_el2(3, 1)
+#define OP_TLBI_ALLE1IS		tlbi_insn_el2(3, 4)
+#define OP_TLBI_VALE2IS		tlbi_insn_el2(3, 5)
+#define OP_TLBI_VMALLS12E1IS	tlbi_insn_el2(3, 6)
+#define OP_TLBI_IPAS2E1		tlbi_insn_el2(4, 1)
+#define OP_TLBI_IPAS2LE1	tlbi_insn_el2(4, 5)
+#define OP_TLBI_ALLE2		tlbi_insn_el2(7, 0)
+#define OP_TLBI_VAE2		tlbi_insn_el2(7, 1)
+#define OP_TLBI_ALLE1		tlbi_insn_el2(7, 4)
+#define OP_TLBI_VALE2		tlbi_insn_el2(7, 5)
+#define OP_TLBI_VMALLS12E1	tlbi_insn_el2(7, 6)
+
 /* Common SCTLR_ELx flags. */
 #define SCTLR_ELx_ENTP2	(BIT(60))
 #define SCTLR_ELx_DSSBS	(BIT(44))
diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c
index 6d186a3e5e5f..a17bf261d501 100644
--- a/arch/arm64/kvm/hyp/vhe/switch.c
+++ b/arch/arm64/kvm/hyp/vhe/switch.c
@@ -47,7 +47,7 @@ static void __activate_traps(struct kvm_vcpu *vcpu)
 			 * the EL1 virtual memory control register accesses
 			 * as well as the AT S1 operations.
 			 */
-			hcr |= HCR_TVM | HCR_TRVM | HCR_AT | HCR_NV1;
+			hcr |= HCR_TVM | HCR_TRVM | HCR_AT | HCR_TTLB | HCR_NV1;
 		} else {
 			/*
 			 * For a guest hypervisor on v8.1 (VHE), allow to
@@ -75,11 +75,11 @@ static void __activate_traps(struct kvm_vcpu *vcpu)
 
 			/*
 			 * If we're using the EL1 translation regime
-			 * (TGE clear), then ensure that AT S1 ops are
-			 * trapped too.
+			 * (TGE clear), then ensure that AT S1 and
+			 * TLBI E1 ops are trapped too.
 			 */
 			if (!vcpu_el2_tge_is_set(vcpu))
-				hcr |= HCR_AT;
+				hcr |= HCR_AT | HCR_TTLB;
 		}
 	}
 
diff --git a/arch/arm64/kvm/hyp/vhe/tlb.c b/arch/arm64/kvm/hyp/vhe/tlb.c
index 24cef9b87f9e..c4389db4cc22 100644
--- a/arch/arm64/kvm/hyp/vhe/tlb.c
+++ b/arch/arm64/kvm/hyp/vhe/tlb.c
@@ -161,3 +161,84 @@ void __kvm_flush_vm_context(void)
 
 	dsb(ish);
 }
+
+void __kvm_tlb_vae2is(struct kvm_s2_mmu *mmu, u64 va, u64 sys_encoding)
+{
+	struct tlb_inv_context cxt;
+
+	dsb(ishst);
+
+	/* Switch to requested VMID */
+	__tlb_switch_to_guest(mmu, &cxt);
+
+	/*
+	 * Execute the EL1 version of TLBI VAE2* instruction, forcing
+	 * an upgrade to the Inner Shareable domain in order to
+	 * perform the invalidation on all CPUs.
+	 */
+	switch (sys_encoding) {
+	case OP_TLBI_VAE2:
+	case OP_TLBI_VAE2IS:
+		__tlbi(vae1is, va);
+		break;
+	case OP_TLBI_VALE2:
+	case OP_TLBI_VALE2IS:
+		__tlbi(vale1is, va);
+		break;
+	default:
+		break;
+	}
+	dsb(ish);
+	isb();
+
+	__tlb_switch_to_host(&cxt);
+}
+
+void __kvm_tlb_el1_instr(struct kvm_s2_mmu *mmu, u64 val, u64 sys_encoding)
+{
+	struct tlb_inv_context cxt;
+
+	dsb(ishst);
+
+	/* Switch to requested VMID */
+	__tlb_switch_to_guest(mmu, &cxt);
+
+	/*
+	 * Execute the same instruction as the guest hypervisor did,
+	 * expanding the scope of local TLB invalidations to the Inner
+	 * Shareable domain so that it takes place on all CPUs. This
+	 * is equivalent to having HCR_EL2.FB set.
+	 */
+	switch (sys_encoding) {
+	case OP_TLBI_VMALLE1:
+	case OP_TLBI_VMALLE1IS:
+		__tlbi(vmalle1is);
+		break;
+	case OP_TLBI_VAE1:
+	case OP_TLBI_VAE1IS:
+		__tlbi(vae1is, val);
+		break;
+	case OP_TLBI_ASIDE1:
+	case OP_TLBI_ASIDE1IS:
+		__tlbi(aside1is, val);
+		break;
+	case OP_TLBI_VAAE1:
+	case OP_TLBI_VAAE1IS:
+		__tlbi(vaae1is, val);
+		break;
+	case OP_TLBI_VALE1:
+	case OP_TLBI_VALE1IS:
+		__tlbi(vale1is, val);
+		break;
+	case OP_TLBI_VAALE1:
+	case OP_TLBI_VAALE1IS:
+		__tlbi(vaale1is, val);
+		break;
+	default:
+		break;
+	}
+	dsb(ish);
+	isb();
+
+	__tlb_switch_to_host(&cxt);
+}
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 6dc82b0384ce..4680a703847b 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -89,7 +89,22 @@ static bool memslot_is_logging(struct kvm_memory_slot *memslot)
 void kvm_flush_remote_tlbs(struct kvm *kvm)
 {
 	++kvm->stat.generic.remote_tlb_flush_requests;
-	kvm_call_hyp(__kvm_tlb_flush_vmid, &kvm->arch.mmu);
+
+	if (!kvm->arch.nested_mmus) {
+		/*
+		 * For a normal (i.e. non-nested) guest, flush entries for the
+		 * given VMID.
+		 */
+		kvm_call_hyp(__kvm_tlb_flush_vmid, &kvm->arch.mmu);
+	} else {
+		/*
+		 * When supporting nested virtualization, we can have multiple
+		 * VMIDs in play for each VCPU in the VM, so it's really not
+		 * worth it to try to quiesce the system and flush all the
+		 * VMIDs that may be in use, instead just nuke the whole thing.
+		 */
+		kvm_call_hyp(__kvm_flush_vm_context);
+	}
 }
 
 static bool kvm_is_device_pfn(unsigned long pfn)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 66a379baf8c7..40215710ede2 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -2603,6 +2603,205 @@ static bool handle_s12w(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
 	return handle_s12(vcpu, p, r, true);
 }
 
+static bool handle_alle2is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			   const struct sys_reg_desc *r)
+{
+	if (vcpu_has_nv(vcpu) && forward_nv_traps(vcpu))
+		return false;
+
+	/*
+	 * To emulate invalidating all EL2 regime stage 1 TLB entries for all
+	 * PEs, executing TLBI VMALLE1IS is enough. But reuse the existing
+	 * interface for the simplicity; invalidating stage 2 entries doesn't
+	 * affect the correctness.
+	 */
+	__kvm_tlb_flush_vmid(&vcpu->kvm->arch.mmu);
+	return true;
+}
+
+static bool handle_vae2is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			  const struct sys_reg_desc *r)
+{
+	int sys_encoding = sys_insn(p->Op0, p->Op1, p->CRn, p->CRm, p->Op2);
+
+	if (vcpu_has_nv(vcpu) && forward_nv_traps(vcpu))
+		return false;
+
+	/*
+	 * Based on the same principle as TLBI ALLE2 instruction
+	 * emulation, we emulate TLBI VAE2* instructions by executing
+	 * corresponding TLBI VAE1* instructions with the virtual
+	 * EL2's VMID assigned by the host hypervisor.
+	 */
+	__kvm_tlb_vae2is(&vcpu->kvm->arch.mmu, p->regval, sys_encoding);
+	return true;
+}
+
+static bool handle_alle1is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			   const struct sys_reg_desc *r)
+{
+	struct kvm_s2_mmu *mmu = &vcpu->kvm->arch.mmu;
+
+	if (vcpu_has_nv(vcpu) && forward_nv_traps(vcpu))
+		return false;
+
+	write_lock(&vcpu->kvm->mmu_lock);
+
+	/*
+	 * Clear all mappings in the shadow page tables and invalidate the stage
+	 * 1 and 2 TLB entries via kvm_tlb_flush_vmid_ipa().
+	 */
+	kvm_nested_s2_unmap(vcpu->kvm);
+
+	if (atomic64_read(&mmu->vmid.id)) {
+		/*
+		 * Invalidate the stage 1 and 2 TLB entries for the host OS
+		 * in a VM only if there is one.
+		 */
+		__kvm_tlb_flush_vmid(mmu);
+	}
+
+	write_unlock(&vcpu->kvm->mmu_lock);
+
+	return true;
+}
+
+static bool handle_vmalls12e1is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+				const struct sys_reg_desc *r)
+{
+	struct kvm_s2_mmu *mmu;
+	u64 vttbr;
+
+	if (vcpu_has_nv(vcpu) && forward_nv_traps(vcpu))
+		return false;
+
+	vttbr = vcpu_read_sys_reg(vcpu, VTTBR_EL2);
+	write_lock(&vcpu->kvm->mmu_lock);
+
+	mmu = lookup_s2_mmu(vcpu->kvm, vttbr, HCR_VM);
+	if (mmu)
+		kvm_unmap_stage2_range(mmu, 0, kvm_phys_size(vcpu->kvm));
+
+	mmu = lookup_s2_mmu(vcpu->kvm, vttbr, 0);
+	if (mmu)
+		kvm_unmap_stage2_range(mmu, 0, kvm_phys_size(vcpu->kvm));
+
+	write_unlock(&vcpu->kvm->mmu_lock);
+
+	return true;
+}
+
+static bool handle_ipas2e1is(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			     const struct sys_reg_desc *r)
+{
+	u64 vttbr = vcpu_read_sys_reg(vcpu, VTTBR_EL2);
+	u64 vtcr = vcpu_read_sys_reg(vcpu, VTCR_EL2);
+	struct kvm_s2_mmu *mmu;
+	u64 base_addr;
+	int max_size;
+
+	if (vcpu_has_nv(vcpu) && forward_nv_traps(vcpu))
+		return false;
+
+	/*
+	 * We drop a number of things from the supplied value:
+	 *
+	 * - NS bit: we're non-secure only.
+	 *
+	 * - TTL field: We already have the granule size from the
+	 *   VTCR_EL2.TG0 field, and the level is only relevant to the
+	 *   guest's S2PT.
+	 *
+	 * - IPA[51:48]: We don't support 52bit IPA just yet...
+	 *
+	 * And of course, adjust the IPA to be on an actual address.
+	 */
+	base_addr = (p->regval & GENMASK_ULL(35, 0)) << 12;
+
+	/* Compute the maximum extent of the invalidation */
+	switch ((vtcr & VTCR_EL2_TG0_MASK)) {
+	case VTCR_EL2_TG0_4K:
+		max_size = SZ_1G;
+		break;
+	case VTCR_EL2_TG0_16K:
+		max_size = SZ_32M;
+		break;
+	case VTCR_EL2_TG0_64K:
+		/*
+		 * No, we do not support 52bit IPA in nested yet. Once
+		 * we do, this should be 4TB.
+		 */
+		/* FIXME: remove the 52bit PA support from the IDregs */
+		max_size = SZ_512M;
+		break;
+	default:
+		BUG();
+	}
+
+	write_lock(&vcpu->kvm->mmu_lock);
+
+	mmu = lookup_s2_mmu(vcpu->kvm, vttbr, HCR_VM);
+	if (mmu)
+		kvm_unmap_stage2_range(mmu, base_addr, max_size);
+
+	mmu = lookup_s2_mmu(vcpu->kvm, vttbr, 0);
+	if (mmu)
+		kvm_unmap_stage2_range(mmu, base_addr, max_size);
+
+	write_unlock(&vcpu->kvm->mmu_lock);
+
+	return true;
+}
+
+static bool handle_tlbi_el1(struct kvm_vcpu *vcpu, struct sys_reg_params *p,
+			    const struct sys_reg_desc *r)
+{
+	u32 sys_encoding = sys_insn(p->Op0, p->Op1, p->CRn, p->CRm, p->Op2);
+
+	if (vcpu_has_nv(vcpu) && forward_traps(vcpu, HCR_TTLB))
+		return false;
+
+	/*
+	 * If we're here, this is because we've trapped on a EL1 TLBI
+	 * instruction that affects the EL1 translation regime while
+	 * we're running in a context that doesn't allow us to let the
+	 * HW do its thing (aka vEL2):
+	 *
+	 * - HCR_EL2.E2H == 0 : a non-VHE guest
+	 * - HCR_EL2.{E2H,TGE} == { 1, 0 } : a VHE guest in guest mode
+	 *
+	 * We don't expect these helpers to ever be called when running
+	 * in a vEL1 context.
+	 */
+
+	WARN_ON(!vcpu_is_el2(vcpu));
+
+	mutex_lock(&vcpu->kvm->lock);
+
+	if ((__vcpu_sys_reg(vcpu, HCR_EL2) & (HCR_E2H | HCR_TGE)) != (HCR_E2H | HCR_TGE)) {
+		u64 virtual_vttbr = vcpu_read_sys_reg(vcpu, VTTBR_EL2);
+		struct kvm_s2_mmu *mmu;
+
+		mmu = lookup_s2_mmu(vcpu->kvm, virtual_vttbr, HCR_VM);
+		if (mmu)
+			__kvm_tlb_el1_instr(mmu, p->regval, sys_encoding);
+
+		mmu = lookup_s2_mmu(vcpu->kvm, virtual_vttbr, 0);
+		if (mmu)
+			__kvm_tlb_el1_instr(mmu, p->regval, sys_encoding);
+	} else {
+		/*
+		 * ARMv8.4-NV allows the guest to change TGE behind
+		 * our back, so we always trap EL1 TLBIs from vEL2...
+		 */
+		__kvm_tlb_el1_instr(&vcpu->kvm->arch.mmu, p->regval, sys_encoding);
+	}
+
+	mutex_unlock(&vcpu->kvm->lock);
+
+	return true;
+}
+
 /*
  * AT instruction emulation
  *
@@ -2688,12 +2887,40 @@ static struct sys_reg_desc sys_insn_descs[] = {
 	{ SYS_DESC(SYS_DC_CSW), access_dcsw },
 	{ SYS_DESC(SYS_DC_CISW), access_dcsw },
 
+	SYS_INSN(TLBI_VMALLE1IS, handle_tlbi_el1),
+	SYS_INSN(TLBI_VAE1IS, handle_tlbi_el1),
+	SYS_INSN(TLBI_ASIDE1IS, handle_tlbi_el1),
+	SYS_INSN(TLBI_VAAE1IS, handle_tlbi_el1),
+	SYS_INSN(TLBI_VALE1IS, handle_tlbi_el1),
+	SYS_INSN(TLBI_VAALE1IS, handle_tlbi_el1),
+	SYS_INSN(TLBI_VMALLE1, handle_tlbi_el1),
+	SYS_INSN(TLBI_VAE1, handle_tlbi_el1),
+	SYS_INSN(TLBI_ASIDE1, handle_tlbi_el1),
+	SYS_INSN(TLBI_VAAE1, handle_tlbi_el1),
+	SYS_INSN(TLBI_VALE1, handle_tlbi_el1),
+	SYS_INSN(TLBI_VAALE1, handle_tlbi_el1),
+
 	SYS_INSN(AT_S1E2R, handle_s1e2),
 	SYS_INSN(AT_S1E2W, handle_s1e2),
 	SYS_INSN(AT_S12E1R, handle_s12r),
 	SYS_INSN(AT_S12E1W, handle_s12w),
 	SYS_INSN(AT_S12E0R, handle_s12r),
 	SYS_INSN(AT_S12E0W, handle_s12w),
+
+	SYS_INSN(TLBI_IPAS2E1IS, handle_ipas2e1is),
+	SYS_INSN(TLBI_IPAS2LE1IS, handle_ipas2e1is),
+	SYS_INSN(TLBI_ALLE2IS, handle_alle2is),
+	SYS_INSN(TLBI_VAE2IS, handle_vae2is),
+	SYS_INSN(TLBI_ALLE1IS, handle_alle1is),
+	SYS_INSN(TLBI_VALE2IS, handle_vae2is),
+	SYS_INSN(TLBI_VMALLS12E1IS, handle_vmalls12e1is),
+	SYS_INSN(TLBI_IPAS2E1, handle_ipas2e1is),
+	SYS_INSN(TLBI_IPAS2LE1, handle_ipas2e1is),
+	SYS_INSN(TLBI_ALLE2, handle_alle2is),
+	SYS_INSN(TLBI_VAE2, handle_vae2is),
+	SYS_INSN(TLBI_ALLE1, handle_alle1is),
+	SYS_INSN(TLBI_VALE2, handle_vae2is),
+	SYS_INSN(TLBI_VMALLS12E1, handle_vmalls12e1is),
 };
 
 static bool trap_dbgdidr(struct kvm_vcpu *vcpu,
-- 
2.34.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  parent reply	other threads:[~2023-01-31  9:43 UTC|newest]

Thread overview: 170+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-01-31  9:23 [PATCH v8 00/69] KVM: arm64: ARMv8.3/8.4 Nested Virtualization support Marc Zyngier
2023-01-31  9:23 ` Marc Zyngier
2023-01-31  9:23 ` [PATCH v8 01/69] arm64: Add ARM64_HAS_NESTED_VIRT cpufeature Marc Zyngier
2023-01-31  9:23   ` Marc Zyngier
2023-01-31 12:03   ` Catalin Marinas
2023-01-31 12:03     ` Catalin Marinas
2023-01-31 13:21     ` Marc Zyngier
2023-01-31 13:21       ` Marc Zyngier
2023-01-31 13:47   ` Suzuki K Poulose
2023-01-31 13:47     ` Suzuki K Poulose
2023-01-31 14:00     ` Marc Zyngier
2023-01-31 14:00       ` Marc Zyngier
2023-01-31 17:34       ` Suzuki K Poulose
2023-01-31 17:34         ` Suzuki K Poulose
2023-01-31 20:04         ` Oliver Upton
2023-01-31 20:04           ` Oliver Upton
2023-01-31 21:26           ` Marc Zyngier
2023-01-31 21:26             ` Marc Zyngier
2023-01-31 22:01             ` Oliver Upton
2023-01-31 22:01               ` Oliver Upton
2023-01-31 20:44         ` Marc Zyngier
2023-01-31 20:44           ` Marc Zyngier
2023-01-31  9:23 ` [PATCH v8 02/69] KVM: arm64: Use the S2 MMU context to iterate over S2 table Marc Zyngier
2023-01-31  9:23   ` Marc Zyngier
2023-01-31  9:23 ` [PATCH v8 03/69] KVM: arm64: nv: Introduce nested virtualization VCPU feature Marc Zyngier
2023-01-31  9:23   ` Marc Zyngier
2023-01-31  9:23 ` [PATCH v8 04/69] KVM: arm64: nv: Reset VCPU to EL2 registers if VCPU nested virt is set Marc Zyngier
2023-01-31  9:23   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 05/69] KVM: arm64: nv: Allow userspace to set PSR_MODE_EL2x Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 06/69] KVM: arm64: nv: Add EL2 system registers to vcpu context Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 07/69] KVM: arm64: nv: Add nested virt VCPU primitives for vEL2 VCPU state Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 08/69] KVM: arm64: nv: Handle HCR_EL2.NV system register traps Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 09/69] KVM: arm64: nv: Reset VMPIDR_EL2 and VPIDR_EL2 to sane values Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31 20:17   ` Oliver Upton
2023-01-31 20:17     ` Oliver Upton
2023-01-31 22:04     ` Marc Zyngier
2023-01-31 22:04       ` Marc Zyngier
2023-01-31 22:09       ` Oliver Upton
2023-01-31 22:09         ` Oliver Upton
2023-01-31 22:16         ` Marc Zyngier
2023-01-31 22:16           ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 10/69] KVM: arm64: nv: Support virtual EL2 exceptions Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 11/69] KVM: arm64: nv: Inject HVC exceptions to the virtual EL2 Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 12/69] KVM: arm64: nv: Handle trapped ERET from " Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 13/69] KVM: arm64: nv: Add non-VHE-EL2->EL1 translation helpers Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 14/69] KVM: arm64: nv: Handle virtual EL2 registers in vcpu_read/write_sys_reg() Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 15/69] KVM: arm64: nv: Handle SPSR_EL2 specially Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 16/69] KVM: arm64: nv: Handle HCR_EL2.E2H specially Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 17/69] KVM: arm64: nv: Save/Restore vEL2 sysregs Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 18/69] KVM: arm64: nv: Emulate PSTATE.M for a guest hypervisor Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 19/69] KVM: arm64: nv: Trap EL1 VM register accesses in virtual EL2 Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 20/69] KVM: arm64: nv: Add accessors for SPSR_EL1, ELR_EL1 and VBAR_EL1 from " Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 21/69] KVM: arm64: nv: Trap CPACR_EL1 access in " Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 22/69] KVM: arm64: nv: Handle PSCI call via smc from the guest Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 23/69] KVM: arm64: nv: Respect virtual HCR_EL2.TWX setting Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 24/69] KVM: arm64: nv: Respect virtual CPTR_EL2.{TFP,FPEN} settings Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 25/69] KVM: arm64: nv: Respect the virtual HCR_EL2.NV bit setting Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 26/69] KVM: arm64: nv: Respect virtual HCR_EL2.TVM and TRVM settings Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 27/69] KVM: arm64: nv: Respect the virtual HCR_EL2.NV1 bit setting Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 28/69] KVM: arm64: nv: Allow a sysreg to be hidden from userspace only Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 29/69] KVM: arm64: nv: Emulate EL12 register accesses from the virtual EL2 Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 30/69] KVM: arm64: nv: Forward debug traps to the nested guest Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 31/69] KVM: arm64: nv: Configure HCR_EL2 for nested virtualization Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 32/69] KVM: arm64: nv: Only toggle cache for virtual EL2 when SCTLR_EL2 changes Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 33/69] KVM: arm64: nv: Filter out unsupported features from ID regs Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 34/69] KVM: arm64: nv: Hide RAS from nested guests Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 35/69] KVM: arm64: nv: Support multiple nested Stage-2 mmu structures Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 36/69] KVM: arm64: nv: Implement nested Stage-2 page table walk logic Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 37/69] KVM: arm64: nv: Handle shadow stage 2 page faults Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 38/69] KVM: arm64: nv: Restrict S2 RD/WR permissions to match the guest's Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 39/69] KVM: arm64: nv: Unmap/flush shadow stage 2 page tables Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 40/69] KVM: arm64: nv: Set a handler for the system instruction traps Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 41/69] KVM: arm64: nv: Trap and emulate AT instructions from virtual EL2 Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` Marc Zyngier [this message]
2023-01-31  9:24   ` [PATCH v8 42/69] KVM: arm64: nv: Trap and emulate TLBI " Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 43/69] KVM: arm64: nv: Fold guest's HCR_EL2 configuration into the host's Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 44/69] KVM: arm64: nv: arch_timer: Support hyp timer emulation Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 45/69] KVM: arm64: nv: Add handling of EL2-specific timer registers Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 46/69] KVM: arm64: nv: Load timer before the GIC Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 47/69] KVM: arm64: nv: Nested GICv3 Support Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 48/69] KVM: arm64: nv: Don't load the GICv4 context on entering a nested guest Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 49/69] KVM: arm64: nv: vgic: Emulate the HW bit in software Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 50/69] KVM: arm64: nv: vgic: Allow userland to set VGIC maintenance IRQ Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 51/69] KVM: arm64: nv: Implement maintenance interrupt forwarding Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 52/69] KVM: arm64: nv: Deal with broken VGIC on maintenance interrupt delivery Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 53/69] KVM: arm64: nv: Add nested GICv3 tracepoints Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 54/69] KVM: arm64: nv: Allow userspace to request KVM_ARM_VCPU_NESTED_VIRT Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 55/69] KVM: arm64: nv: Add handling of FEAT_TTL TLB invalidation Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 56/69] KVM: arm64: nv: Invalidate TLBs based on shadow S2 TTL-like information Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 57/69] KVM: arm64: nv: Tag shadow S2 entries with nested level Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 58/69] KVM: arm64: nv: Add include containing the VNCR_EL2 offsets Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 59/69] KVM: arm64: nv: Map VNCR-capable registers to a separate page Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 60/69] KVM: arm64: nv: Move nested vgic state into the sysreg file Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 61/69] KVM: arm64: Add FEAT_NV2 cpu feature Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 62/69] KVM: arm64: nv: Sync nested timer state with FEAT_NV2 Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 63/69] KVM: arm64: nv: Publish emulated timer interrupt state in the in-memory state Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:24 ` [PATCH v8 64/69] KVM: arm64: nv: Allocate VNCR page when required Marc Zyngier
2023-01-31  9:24   ` Marc Zyngier
2023-01-31  9:25 ` [PATCH v8 65/69] KVM: arm64: nv: Enable ARMv8.4-NV support Marc Zyngier
2023-01-31  9:25   ` Marc Zyngier
2023-01-31  9:25 ` [PATCH v8 66/69] KVM: arm64: nv: Fast-track 'InHost' exception returns Marc Zyngier
2023-01-31  9:25   ` Marc Zyngier
2023-01-31  9:25 ` [PATCH v8 67/69] KVM: arm64: nv: Fast-track EL1 TLBIs for VHE guests Marc Zyngier
2023-01-31  9:25   ` Marc Zyngier
2023-01-31  9:25 ` [PATCH v8 68/69] KVM: arm64: nv: Use FEAT_ECV to trap access to EL0 timers Marc Zyngier
2023-01-31  9:25   ` Marc Zyngier
2023-01-31  9:25 ` [PATCH v8 69/69] KVM: arm64: nv: Accelerate EL0 timer read accesses when FEAT_ECV is on Marc Zyngier
2023-01-31  9:25   ` Marc Zyngier
2023-01-31 22:13 ` [PATCH v8 00/69] KVM: arm64: ARMv8.3/8.4 Nested Virtualization support Oliver Upton
2023-01-31 22:13   ` Oliver Upton
2023-01-31 22:20   ` Marc Zyngier
2023-01-31 22:20     ` Marc Zyngier

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20230131092504.2880505-43-maz@kernel.org \
    --to=maz@kernel.org \
    --cc=alexandru.elisei@arm.com \
    --cc=andre.przywara@arm.com \
    --cc=chase.conklin@arm.com \
    --cc=christoffer.dall@arm.com \
    --cc=gankulkarni@os.amperecomputing.com \
    --cc=james.morse@arm.com \
    --cc=jintack@cs.columbia.edu \
    --cc=kvm@vger.kernel.org \
    --cc=kvmarm@lists.linux.dev \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=oliver.upton@linux.dev \
    --cc=rmk+kernel@armlinux.org.uk \
    --cc=suzuki.poulose@arm.com \
    --cc=yuzenghui@huawei.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.