From e930bffe95e1e886a1ede80726ea38df5838d067 Mon Sep 17 00:00:00 2001 From: Andrea Arcangeli Date: Fri, 25 Jul 2008 16:24:52 +0200 Subject: KVM: Synchronize guest physical memory map to host virtual memory map Synchronize changes to host virtual addresses which are part of a KVM memory slot to the KVM shadow mmu. This allows pte operations like swapping, page migration, and madvise() to transparently work with KVM. Signed-off-by: Andrea Arcangeli Signed-off-by: Avi Kivity --- include/linux/kvm_host.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'include/linux/kvm_host.h') diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 07d68a8..8525afc 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -121,6 +121,12 @@ struct kvm { struct kvm_coalesced_mmio_dev *coalesced_mmio_dev; struct kvm_coalesced_mmio_ring *coalesced_mmio_ring; #endif + +#ifdef KVM_ARCH_WANT_MMU_NOTIFIER + struct mmu_notifier mmu_notifier; + unsigned long mmu_notifier_seq; + long mmu_notifier_count; +#endif }; /* The guest did something we don't support. */ @@ -332,4 +338,22 @@ int kvm_trace_ioctl(unsigned int ioctl, unsigned long arg) #define kvm_trace_cleanup() ((void)0) #endif +#ifdef KVM_ARCH_WANT_MMU_NOTIFIER +static inline int mmu_notifier_retry(struct kvm_vcpu *vcpu, unsigned long mmu_seq) +{ + if (unlikely(vcpu->kvm->mmu_notifier_count)) + return 1; + /* + * Both reads happen under the mmu_lock and both values are + * modified under mmu_lock, so there's no need of smb_rmb() + * here in between, otherwise mmu_notifier_count should be + * read before mmu_notifier_seq, see + * mmu_notifier_invalidate_range_end write side. + */ + if (vcpu->kvm->mmu_notifier_seq != mmu_seq) + return 1; + return 0; +} +#endif + #endif -- cgit v1.1