[PATCH 7/8] kvm/arm64: Implement KVM_CAP_MEM_FAULT_NOWAIT for arm64

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Just do atomic gfn_to_pfn_memslot when the cap is enabled. Since we
don't have to deal with async page faults, the implementation is even
simpler than on x86

Signed-off-by: Anish Moorthy <amoorthy@xxxxxxxxxx>
Acked-by: James Houghton <jthoughton@xxxxxxxxxx>
---
 arch/arm64/kvm/arm.c |  1 +
 arch/arm64/kvm/mmu.c | 14 ++++++++++++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 698787ed87e92..31bec7866c346 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -220,6 +220,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_VCPU_ATTRIBUTES:
 	case KVM_CAP_PTP_KVM:
 	case KVM_CAP_ARM_SYSTEM_SUSPEND:
+	case KVM_CAP_MEM_FAULT_NOWAIT:
 		r = 1;
 		break;
 	case KVM_CAP_SET_GUEST_DEBUG2:
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 01352f5838a00..964af7cd5f1c8 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -1206,6 +1206,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 	unsigned long vma_pagesize, fault_granule;
 	enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_R;
 	struct kvm_pgtable *pgt;
+	bool mem_fault_nowait;
 
 	fault_granule = 1UL << ARM64_HW_PGTABLE_LEVEL_SHIFT(fault_level);
 	write_fault = kvm_is_write_fault(vcpu);
@@ -1301,8 +1302,17 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
 	 */
 	smp_rmb();
 
-	pfn = __gfn_to_pfn_memslot(memslot, gfn, false, false, NULL,
-				   write_fault, &writable, NULL);
+	mem_fault_nowait = memory_faults_enabled(vcpu->kvm);
+	pfn = __gfn_to_pfn_memslot(
+		memslot, gfn, mem_fault_nowait, false, NULL,
+		write_fault, &writable, NULL);
+
+	if (mem_fault_nowait && pfn == KVM_PFN_ERR_FAULT) {
+		vcpu->run->exit_reason = KVM_EXIT_MEMORY_FAULT;
+		vcpu->run->memory_fault.gpa = gfn << PAGE_SHIFT;
+		vcpu->run->memory_fault.size = vma_pagesize;
+		return -EFAULT;
+	}
 	if (pfn == KVM_PFN_ERR_HWPOISON) {
 		kvm_send_hwpoison_signal(hva, vma_shift);
 		return 0;
-- 
2.39.1.581.gbfd45094c4-goog




[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux