[PATCH v7.1 9/9] KVM: arm64: Add support for creating PUD hugepages at stage 2
From: Punit Agrawal <hidden>
Date: 2018-10-01 14:00:44
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kvmarm, lkml
Punit Agrawal [off-list ref] writes:
KVM only supports PMD hugepages at stage 2. Now that the various page handling routines are updated, extend the stage 2 fault handling to map in PUD hugepages. Addition of PUD hugepage support enables additional page sizes (e.g., 1G with 4K granule) which can be useful on cores that support mapping larger block sizes in the TLB entries. Signed-off-by: Punit Agrawal <redacted> Cc: Christoffer Dall <redacted> Cc: Marc Zyngier <redacted> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <redacted> --- v7 -> v7.1 * Added arm helper kvm_stage2_has_pud() * Added check for PUD level present at stage 2 * Dropped redundant comment * Fixed up kvm_pud_mkhuge() to complain on arm arch/arm/include/asm/kvm_mmu.h | 20 +++++ arch/arm/include/asm/stage2_pgtable.h | 5 ++ arch/arm64/include/asm/kvm_mmu.h | 16 ++++ arch/arm64/include/asm/pgtable-hwdef.h | 2 + arch/arm64/include/asm/pgtable.h | 2 + virt/kvm/arm/mmu.c | 106 +++++++++++++++++++++++-- 6 files changed, 145 insertions(+), 6 deletions(-)
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quoted hunk
diff --git a/arch/arm/include/asm/stage2_pgtable.h b/arch/arm/include/asm/stage2_pgtable.h index f6a7ea805232..ec1567d9eb4b 100644 --- a/arch/arm/include/asm/stage2_pgtable.h +++ b/arch/arm/include/asm/stage2_pgtable.h@@ -68,4 +68,9 @@ stage2_pmd_addr_end(struct kvm *kvm, phys_addr_t addr, phys_addr_t end) #define stage2_pmd_table_empty(kvm, pmdp) kvm_page_empty(pmdp) #define stage2_pud_table_empty(kvm, pudp) false +static inline bool kvm_stage2_has_pud(struct kvm *kvm) +{ + return KVM_VTCR_SL0 == VTCR_SL_L1; +} +
Turns out this isn't quite the right check. On arm32, the maximum number of supported levels is 3 with LPAE - effectively the helper should always return false. I've updated the check locally to key off of CONFIG_PGTABLE_LEVELS. I'll post these patches later today. Thanks, Punit