[PATCH v4 01/43] KVM: Prepare for handling only shared mappings in mmu_notifier events

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

 



From: Sean Christopherson <seanjc@xxxxxxxxxx>

Add flags to "struct kvm_gfn_range" to let notifier events target only
shared and only private mappings, and write up the existing mmu_notifier
events to be shared-only (private memory is never associated with a
userspace virtual address, i.e. can't be reached via mmu_notifiers).

Add two flags so that KVM can handle the three possibilities (shared,
private, and shared+private) without needing something like a tri-state
enum.

Link: https://lore.kernel.org/all/ZJX0hk+KpQP0KUyB@xxxxxxxxxx
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Signed-off-by: Steven Price <steven.price@xxxxxxx>
---
 include/linux/kvm_host.h | 2 ++
 virt/kvm/kvm_main.c      | 7 +++++++
 2 files changed, 9 insertions(+)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 689e8be873a7..7393377c7656 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -265,6 +265,8 @@ struct kvm_gfn_range {
 	gfn_t start;
 	gfn_t end;
 	union kvm_mmu_notifier_arg arg;
+	bool only_private;
+	bool only_shared;
 	bool may_block;
 };
 bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index d0788d0a72cc..eaf16195b104 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -631,6 +631,13 @@ static __always_inline kvm_mn_ret_t __kvm_handle_hva_range(struct kvm *kvm,
 			 * the second or later invocation of the handler).
 			 */
 			gfn_range.arg = range->arg;
+
+			/*
+			 * HVA-based notifications aren't relevant to private
+			 * mappings as they don't have a userspace mapping.
+			 */
+			gfn_range.only_private = false;
+			gfn_range.only_shared = true;
 			gfn_range.may_block = range->may_block;
 
 			/*
-- 
2.34.1





[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