[PATCH v3 07/21] KVM: Cache as_id in kvm_memory_slot

[Peter Xu]

Cache the address space ID just like the slot ID.  It will be used in
order to fill in the dirty ring entries.

Suggested-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Suggested-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---
 include/linux/kvm_host.h | 1 +
 virt/kvm/kvm_main.c      | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 2337f9b6112c..763adf8c47b0 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -348,6 +348,7 @@ struct kvm_memory_slot {
 	unsigned long userspace_addr;
 	u32 flags;
 	short id;
+	u8 as_id;
 };
 
 static inline unsigned long kvm_dirty_bitmap_bytes(struct kvm_memory_slot *memslot)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 70b78ccaf3b5..1fd204f27028 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1040,6 +1040,8 @@ int __kvm_set_memory_region(struct kvm *kvm,
 
 	new = old = *slot;
 
+	BUILD_BUG_ON(U8_MAX < KVM_ADDRESS_SPACE_NUM);
+	new.as_id = as_id;
 	new.id = id;
 	new.base_gfn = base_gfn;
 	new.npages = npages;
-- 
2.24.1