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[11/24] KVM: arm64: Clean up the checking for huge mapping

Message ID 20200529160121.899083-12-maz@kernel.org (mailing list archive)
State Mainlined
Commit 9f2836146b11cdf98d5c8f8f71b0fce28fbd83c8
Headers show
Series [GIT,PULL] KVM/arm64 updates for Linux 5.8 | expand

Commit Message

Marc Zyngier May 29, 2020, 4:01 p.m. UTC 
From: Suzuki K Poulose <suzuki.poulose@arm.com>

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.

While we're at it, fixup a typo in the comment below.

Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200507123546.1875-2-yuzenghui@huawei.com
---
 arch/arm64/kvm/mmu.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 917363375e8a..ccb44e7d30d9 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1610,6 +1610,10 @@  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;
@@ -1629,7 +1633,7 @@  static bool fault_supports_stage2_huge_mapping(struct kvm_memory_slot *memslot,
 	 *    |abcde|fgh  Stage-1 block  |    Stage-1 block tv|xyz|
 	 *    +-----+--------------------+--------------------+---+
 	 *
-	 *    memslot->base_gfn << PAGE_SIZE:
+	 *    memslot->base_gfn << PAGE_SHIFT:
 	 *      +---+--------------------+--------------------+-----+
 	 *      |abc|def  Stage-2 block  |    Stage-2 block   |tvxyz|
 	 *      +---+--------------------+--------------------+-----+