Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 163 insertions, 0 deletions

diff --git a/arch/arm64/kvm/hyp/vhe/tlb.c b/arch/arm64/kvm/hyp/vhe/tlb.c
new file mode 100644
index 000000000..24cef9b87
--- /dev/null
+++ b/arch/arm64/kvm/hyp/vhe/tlb.c
@@ -0,0 +1,163 @@
+// 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 __tlb_switch_to_guest(struct kvm_s2_mmu *mmu,
+				  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_stage2() already
+	 * has an ISB in order to deal with this.
+	 */
+	__load_stage2(mmu, mmu->arch);
+	val = read_sysreg(hcr_el2);
+	val &= ~HCR_TGE;
+	write_sysreg(val, hcr_el2);
+	isb();
+}
+
+static void __tlb_switch_to_host(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);
+}
+
+void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu,
+			      phys_addr_t ipa, int level)
+{
+	struct tlb_inv_context cxt;
+
+	dsb(ishst);
+
+	/* Switch to requested VMID */
+	__tlb_switch_to_guest(mmu, &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_level(ipas2e1is, ipa, level);
+
+	/*
+	 * 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();
+
+	__tlb_switch_to_host(&cxt);
+}
+
+void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu)
+{
+	struct tlb_inv_context cxt;
+
+	dsb(ishst);
+
+	/* Switch to requested VMID */
+	__tlb_switch_to_guest(mmu, &cxt);
+
+	__tlbi(vmalls12e1is);
+	dsb(ish);
+	isb();
+
+	__tlb_switch_to_host(&cxt);
+}
+
+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);
+
+	__tlbi(vmalle1);
+	asm volatile("ic iallu");
+	dsb(nsh);
+	isb();
+
+	__tlb_switch_to_host(&cxt);
+}
+
+void __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);
+}