@@ -44,12 +44,11 @@ struct kvm_page_track_notifier_node {
struct kvm_page_track_notifier_node *node);
};
-void
-kvm_page_track_register_notifier(struct kvm *kvm,
- struct kvm_page_track_notifier_node *n);
-void
-kvm_page_track_unregister_notifier(struct kvm *kvm,
- struct kvm_page_track_notifier_node *n);
+int kvm_page_track_register_notifier(struct kvm *kvm,
+ struct kvm_page_track_notifier_node *n);
+void kvm_page_track_unregister_notifier(struct kvm *kvm,
+ struct kvm_page_track_notifier_node *n);
+
int kvm_write_track_add_gfn(struct kvm *kvm, gfn_t gfn);
int kvm_write_track_remove_gfn(struct kvm *kvm, gfn_t gfn);
#else
@@ -157,17 +157,22 @@ int kvm_page_track_init(struct kvm *kvm)
* register the notifier so that event interception for the tracked guest
* pages can be received.
*/
-void
-kvm_page_track_register_notifier(struct kvm *kvm,
- struct kvm_page_track_notifier_node *n)
+int kvm_page_track_register_notifier(struct kvm *kvm,
+ struct kvm_page_track_notifier_node *n)
{
struct kvm_page_track_notifier_head *head;
+ if (!kvm || kvm->mm != current->mm)
+ return -ESRCH;
+
+ kvm_get_kvm(kvm);
+
head = &kvm->arch.track_notifier_head;
write_lock(&kvm->mmu_lock);
hlist_add_head_rcu(&n->node, &head->track_notifier_list);
write_unlock(&kvm->mmu_lock);
+ return 0;
}
EXPORT_SYMBOL_GPL(kvm_page_track_register_notifier);
@@ -175,9 +180,8 @@ EXPORT_SYMBOL_GPL(kvm_page_track_register_notifier);
* stop receiving the event interception. It is the opposed operation of
* kvm_page_track_register_notifier().
*/
-void
-kvm_page_track_unregister_notifier(struct kvm *kvm,
- struct kvm_page_track_notifier_node *n)
+void kvm_page_track_unregister_notifier(struct kvm *kvm,
+ struct kvm_page_track_notifier_node *n)
{
struct kvm_page_track_notifier_head *head;
@@ -187,6 +191,8 @@ kvm_page_track_unregister_notifier(struct kvm *kvm,
hlist_del_rcu(&n->node);
write_unlock(&kvm->mmu_lock);
synchronize_srcu(&head->track_srcu);
+
+ kvm_put_kvm(kvm);
}
EXPORT_SYMBOL_GPL(kvm_page_track_unregister_notifier);
@@ -653,21 +653,19 @@ static bool __kvmgt_vgpu_exist(struct intel_vgpu *vgpu)
static int intel_vgpu_open_device(struct vfio_device *vfio_dev)
{
struct intel_vgpu *vgpu = vfio_dev_to_vgpu(vfio_dev);
-
- if (!vgpu->vfio_device.kvm ||
- vgpu->vfio_device.kvm->mm != current->mm) {
- gvt_vgpu_err("KVM is required to use Intel vGPU\n");
- return -ESRCH;
- }
+ int ret;
if (__kvmgt_vgpu_exist(vgpu))
return -EEXIST;
vgpu->track_node.track_write = kvmgt_page_track_write;
vgpu->track_node.track_remove_region = kvmgt_page_track_remove_region;
- kvm_get_kvm(vgpu->vfio_device.kvm);
- kvm_page_track_register_notifier(vgpu->vfio_device.kvm,
- &vgpu->track_node);
+ ret = kvm_page_track_register_notifier(vgpu->vfio_device.kvm,
+ &vgpu->track_node);
+ if (ret) {
+ gvt_vgpu_err("KVM is required to use Intel vGPU\n");
+ return ret;
+ }
set_bit(INTEL_VGPU_STATUS_ATTACHED, vgpu->status);
@@ -702,7 +700,6 @@ static void intel_vgpu_close_device(struct vfio_device *vfio_dev)
kvm_page_track_unregister_notifier(vgpu->vfio_device.kvm,
&vgpu->track_node);
- kvm_put_kvm(vgpu->vfio_device.kvm);
kvmgt_protect_table_destroy(vgpu);
gvt_cache_destroy(vgpu);
Get/put references to KVM when a page-track notifier is (un)registered instead of relying on the caller to do so. Forcing the caller to do the bookkeeping is unnecessary and adds one more thing for users to get wrong, e.g. see commit 9ed1fdee9ee3 ("drm/i915/gvt: Get reference to KVM iff attachment to VM is successful"). Reviewed-by: Yan Zhao <yan.y.zhao@intel.com> Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/x86/include/asm/kvm_page_track.h | 11 +++++------ arch/x86/kvm/mmu/page_track.c | 18 ++++++++++++------ drivers/gpu/drm/i915/gvt/kvmgt.c | 17 +++++++---------- 3 files changed, 24 insertions(+), 22 deletions(-)