[PATCH 08/26] KVM: arm64: Use TTL hint in when invalidating stage-2 translations

Marc Zyngier
2020-04-22T12:01:19Z

Since we always have a precide idea of the level we're dealing with
when invalidating TLBs, we can provide it to as a hint to our
invalidation helper.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/include/asm/stage2_pgtable.h | 9 +++++++++
virt/kvm/arm/mmu.c | 27 +++++++++++++------------
2 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/arch/arm64/include/asm/stage2_pgtable.h b/arch/arm64/include/asm/stage2_pgtable.h
index 326aac658b9da..7ed5c1a769a9b 100644
--- a/arch/arm64/include/asm/stage2_pgtable.h
+++ b/arch/arm64/include/asm/stage2_pgtable.h
@@ -230,4 +230,13 @@ stage2_pgd_addr_end(struct kvm *kvm, phys_addr_t addr, phys_addr_t end)
return (boundary - 1 < end - 1) ? boundary : end;
}

+/*
+ * Level values for the ARMv8.4-TTL extension, mapping PUD/PMD/PTE and
+ * the architectural page-table level.
+ */
+#define S2_NO_LEVEL_HINT 0
+#define S2_PUD_LEVEL 1
+#define S2_PMD_LEVEL 2
+#define S2_PTE_LEVEL 3
+
#endif /* __ARM64_S2_PGTABLE_H_ */
diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index 611234e0aef12..2c132f5595c4b 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -58,9 +58,10 @@ void kvm_flush_remote_tlbs(struct kvm *kvm)
kvm_call_hyp(__kvm_tlb_flush_vmid, &kvm->arch.mmu);
}

-static void kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa)
+static void kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa,
+ int level)
{
- kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, mmu, ipa, 0);
+ kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, mmu, ipa, level);
}

/*
@@ -102,7 +103,7 @@ static void stage2_dissolve_pmd(struct kvm_s2_mmu *mmu, phys_addr_t addr, pmd_t
return;

pmd_clear(pmd);
- kvm_tlb_flush_vmid_ipa(mmu, addr);
+ kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PMD_LEVEL);
put_page(virt_to_page(pmd));
}

@@ -122,7 +123,7 @@ static void stage2_dissolve_pud(struct kvm_s2_mmu *mmu, phys_addr_t addr, pud_t
return;

stage2_pud_clear(kvm, pudp);
- kvm_tlb_flush_vmid_ipa(mmu, addr);
+ kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PUD_LEVEL);
put_page(virt_to_page(pudp));
}

@@ -164,7 +165,7 @@ static void clear_stage2_pgd_entry(struct kvm_s2_mmu *mmu, pgd_t *pgd, phys_addr

pud_t *pud_table __maybe_unused = stage2_pud_offset(kvm, pgd, 0UL);
stage2_pgd_clear(kvm, pgd);
- kvm_tlb_flush_vmid_ipa(mmu, addr);
+ kvm_tlb_flush_vmid_ipa(mmu, addr, S2_NO_LEVEL_HINT);
stage2_pud_free(kvm, pud_table);
put_page(virt_to_page(pgd));
}
@@ -176,7 +177,7 @@ static void clear_stage2_pud_entry(struct kvm_s2_mmu *mmu, pud_t *pud, phys_addr
pmd_t *pmd_table __maybe_unused = stage2_pmd_offset(kvm, pud, 0);
VM_BUG_ON(stage2_pud_huge(kvm, *pud));
stage2_pud_clear(kvm, pud);
- kvm_tlb_flush_vmid_ipa(mmu, addr);
+ kvm_tlb_flush_vmid_ipa(mmu, addr, S2_NO_LEVEL_HINT);
stage2_pmd_free(kvm, pmd_table);
put_page(virt_to_page(pud));
}
@@ -186,7 +187,7 @@ static void clear_stage2_pmd_entry(struct kvm_s2_mmu *mmu, pmd_t *pmd, phys_addr
pte_t *pte_table = pte_offset_kernel(pmd, 0);
VM_BUG_ON(pmd_thp_or_huge(*pmd));
pmd_clear(pmd);
- kvm_tlb_flush_vmid_ipa(mmu, addr);
+ kvm_tlb_flush_vmid_ipa(mmu, addr, S2_NO_LEVEL_HINT);
free_page((unsigned long)pte_table);
put_page(virt_to_page(pmd));
}
@@ -256,7 +257,7 @@ static void unmap_stage2_ptes(struct kvm_s2_mmu *mmu, pmd_t *pmd,
pte_t old_pte = *pte;

kvm_set_pte(pte, __pte(0));
- kvm_tlb_flush_vmid_ipa(mmu, addr);
+ kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PTE_LEVEL);

/* No need to invalidate the cache for device mappings */
if (!kvm_is_device_pfn(pte_pfn(old_pte)))
@@ -285,7 +286,7 @@ static void unmap_stage2_pmds(struct kvm_s2_mmu *mmu, pud_t *pud,
pmd_t old_pmd = *pmd;

pmd_clear(pmd);
- kvm_tlb_flush_vmid_ipa(mmu, addr);
+ kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PMD_LEVEL);

kvm_flush_dcache_pmd(old_pmd);

@@ -315,7 +316,7 @@ static void unmap_stage2_puds(struct kvm_s2_mmu *mmu, pgd_t *pgd,
pud_t old_pud = *pud;

stage2_pud_clear(kvm, pud);
- kvm_tlb_flush_vmid_ipa(mmu, addr);
+ kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PUD_LEVEL);
kvm_flush_dcache_pud(old_pud);
put_page(virt_to_page(pud));
} else {
@@ -1129,7 +1130,7 @@ static int stage2_set_pmd_huge(struct kvm_s2_mmu *mmu,
*/
WARN_ON_ONCE(pmd_pfn(old_pmd) != pmd_pfn(*new_pmd));
pmd_clear(pmd);
- kvm_tlb_flush_vmid_ipa(mmu, addr);
+ kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PMD_LEVEL);
} else {
get_page(virt_to_page(pmd));
}
@@ -1171,7 +1172,7 @@ static int stage2_set_pud_huge(struct kvm_s2_mmu *mmu,

WARN_ON_ONCE(kvm_pud_pfn(old_pud) != kvm_pud_pfn(*new_pudp));
stage2_pud_clear(kvm, pudp);
- kvm_tlb_flush_vmid_ipa(mmu, addr);
+ kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PUD_LEVEL);
} else {
get_page(virt_to_page(pudp));
}
@@ -1320,7 +1321,7 @@ static int stage2_set_pte(struct kvm_s2_mmu *mmu,
return 0;

kvm_set_pte(pte, __pte(0));
- kvm_tlb_flush_vmid_ipa(mmu, addr);
+ kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PTE_LEVEL);
} else {
get_page(virt_to_page(pte));
}
--
2.26.1