Re: [PATCH 1/2] kvm: arm: Clean up the checking for huge mapping
On 04/11/2019 02:48 AM, Zenghui Yu wrote: On 2019/4/10 23:23, Suzuki K Poulose wrote: If we are checking whether the stage2 can map PAGE_SIZE, we don't have to do the boundary checks as both the host VMA and the guest memslots are page aligned. Bail the case easily. Cc: Christoffer Dall Cc: Marc Zyngier Signed-off-by: Suzuki K Poulose --- virt/kvm/arm/mmu.c | 4 1 file changed, 4 insertions(+) diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index a39dcfd..6d73322 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1624,6 +1624,10 @@ static bool fault_supports_stage2_huge_mapping(struct kvm_memory_slot *memslot, hva_t uaddr_start, uaddr_end; size_t size; + /* The memslot and the VMA are guaranteed to be aligned to PAGE_SIZE */ + if (map_size == PAGE_SIZE) + return true; + size = memslot->npages * PAGE_SIZE; gpa_start = memslot->base_gfn << PAGE_SHIFT; We can do a comment clean up as well in this patch. s/<< PAGE_SIZE/<< PAGE_SHIFT/ Sure, I missed that. Will fix it in the next version. Cheers Suzuki ___ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
Re: [PATCH 1/2] kvm: arm: Clean up the checking for huge mapping
On 2019/4/10 23:23, Suzuki K Poulose wrote: If we are checking whether the stage2 can map PAGE_SIZE, we don't have to do the boundary checks as both the host VMA and the guest memslots are page aligned. Bail the case easily. Cc: Christoffer Dall Cc: Marc Zyngier Signed-off-by: Suzuki K Poulose --- virt/kvm/arm/mmu.c | 4 1 file changed, 4 insertions(+) diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index a39dcfd..6d73322 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1624,6 +1624,10 @@ static bool fault_supports_stage2_huge_mapping(struct kvm_memory_slot *memslot, hva_t uaddr_start, uaddr_end; size_t size; + /* The memslot and the VMA are guaranteed to be aligned to PAGE_SIZE */ + if (map_size == PAGE_SIZE) + return true; + size = memslot->npages * PAGE_SIZE; gpa_start = memslot->base_gfn << PAGE_SHIFT; We can do a comment clean up as well in this patch. s/<< PAGE_SIZE/<< PAGE_SHIFT/ thanks, zenghui ___ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
[PATCH 1/2] kvm: arm: Clean up the checking for huge mapping
If we are checking whether the stage2 can map PAGE_SIZE, we don't have to do the boundary checks as both the host VMA and the guest memslots are page aligned. Bail the case easily. Cc: Christoffer Dall Cc: Marc Zyngier Signed-off-by: Suzuki K Poulose --- virt/kvm/arm/mmu.c | 4 1 file changed, 4 insertions(+) diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index a39dcfd..6d73322 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1624,6 +1624,10 @@ static bool fault_supports_stage2_huge_mapping(struct kvm_memory_slot *memslot, hva_t uaddr_start, uaddr_end; size_t size; + /* The memslot and the VMA are guaranteed to be aligned to PAGE_SIZE */ + if (map_size == PAGE_SIZE) + return true; + size = memslot->npages * PAGE_SIZE; gpa_start = memslot->base_gfn << PAGE_SHIFT; -- 2.7.4 ___ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
