From: Mihai Donțu <mdontu@xxxxxxxxxxxxxxx>
This is used to add page access notifications as soon as a slot appears
or when a slot is moved.
Signed-off-by: Mihai Donțu <mdontu@xxxxxxxxxxxxxxx>
Signed-off-by: Adalbert Lazăr <alazar@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/kvm_page_track.h | 13 ++++++++++++-
arch/x86/kvm/mmu/page_track.c | 17 ++++++++++++++++-
arch/x86/kvm/x86.c | 7 ++++---
3 files changed, 32 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/kvm_page_track.h b/arch/x86/include/asm/kvm_page_track.h
index 9a261e463eb3..00a66c4d4d3c 100644
--- a/arch/x86/include/asm/kvm_page_track.h
+++ b/arch/x86/include/asm/kvm_page_track.h
@@ -36,6 +36,17 @@ struct kvm_page_track_notifier_node {
void (*track_write)(struct kvm_vcpu *vcpu, gpa_t gpa, gva_t gva,
const u8 *new, int bytes,
struct kvm_page_track_notifier_node *node);
+ /*
+ * It is called when memory slot is being created
+ *
+ * @kvm: the kvm where memory slot being moved or removed
+ * @slot: the memory slot being moved or removed
+ * @npages: the number of pages
+ * @node: this node
+ */
+ void (*track_create_slot)(struct kvm *kvm, struct kvm_memory_slot *slot,
+ unsigned long npages,
+ struct kvm_page_track_notifier_node *node);
/*
* It is called when memory slot is being moved or removed
* users can drop write-protection for the pages in that memory slot
@@ -52,7 +63,7 @@ void kvm_page_track_init(struct kvm *kvm);
void kvm_page_track_cleanup(struct kvm *kvm);
void kvm_page_track_free_memslot(struct kvm_memory_slot *slot);
-int kvm_page_track_create_memslot(struct kvm_memory_slot *slot,
+int kvm_page_track_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
unsigned long npages);
void kvm_slot_page_track_add_page(struct kvm *kvm,
diff --git a/arch/x86/kvm/mmu/page_track.c b/arch/x86/kvm/mmu/page_track.c
index d7a591a85af8..27a8d1a02e84 100644
--- a/arch/x86/kvm/mmu/page_track.c
+++ b/arch/x86/kvm/mmu/page_track.c
@@ -28,9 +28,12 @@ void kvm_page_track_free_memslot(struct kvm_memory_slot *slot)
}
}
-int kvm_page_track_create_memslot(struct kvm_memory_slot *slot,
+int kvm_page_track_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
unsigned long npages)
{
+ struct kvm_page_track_notifier_head *head;
+ struct kvm_page_track_notifier_node *n;
+ int idx;
int i;
for (i = 0; i < KVM_PAGE_TRACK_MAX; i++) {
@@ -41,6 +44,18 @@ int kvm_page_track_create_memslot(struct kvm_memory_slot *slot,
goto track_free;
}
+ head = &kvm->arch.track_notifier_head;
+
+ if (hlist_empty(&head->track_notifier_list))
+ return 0;
+
+ idx = srcu_read_lock(&head->track_srcu);
+ hlist_for_each_entry_srcu(n, &head->track_notifier_list, node,
+ srcu_read_lock_held(&head->track_srcu))
+ if (n->track_create_slot)
+ n->track_create_slot(kvm, slot, npages, n);
+ srcu_read_unlock(&head->track_srcu, idx);
+
return 0;
track_free:
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c2f13a275448..4d19da016c12 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10524,7 +10524,8 @@ void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot)
kvm_page_track_free_memslot(slot);
}
-static int kvm_alloc_memslot_metadata(struct kvm_memory_slot *slot,
+static int kvm_alloc_memslot_metadata(struct kvm *kvm,
+ struct kvm_memory_slot *slot,
unsigned long npages)
{
int i;
@@ -10576,7 +10577,7 @@ static int kvm_alloc_memslot_metadata(struct kvm_memory_slot *slot,
}
}
- if (kvm_page_track_create_memslot(slot, npages))
+ if (kvm_page_track_create_memslot(kvm, slot, npages))
goto out_free;
return 0;
@@ -10616,7 +10617,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
enum kvm_mr_change change)
{
if (change == KVM_MR_CREATE || change == KVM_MR_MOVE)
- return kvm_alloc_memslot_metadata(memslot,
+ return kvm_alloc_memslot_metadata(kvm, memslot,
mem->memory_size >> PAGE_SHIFT);
return 0;
}
