Factor out copying kvm_memslots from allocating the memory for new ones
in preparation for adding a new lock to protect the arch-specific fields
of the memslots.
No functional change intended.
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Signed-off-by: Ben Gardon <bgardon@xxxxxxxxxx>
---
virt/kvm/kvm_main.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 6b4feb92dc79..4acd4722d729 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1306,6 +1306,18 @@ static struct kvm_memslots *install_new_memslots(struct kvm *kvm,
return old_memslots;
}
+static size_t kvm_memslots_size(int slots)
+{
+ return sizeof(struct kvm_memslots) +
+ (sizeof(struct kvm_memory_slot) * slots);
+}
+
+static void kvm_copy_memslots(struct kvm_memslots *to,
+ struct kvm_memslots *from)
+{
+ memcpy(to, from, kvm_memslots_size(from->used_slots));
+}
+
/*
* Note, at a minimum, the current number of used slots must be allocated, even
* when deleting a memslot, as we need a complete duplicate of the memslots for
@@ -1315,19 +1327,16 @@ static struct kvm_memslots *kvm_dup_memslots(struct kvm_memslots *old,
enum kvm_mr_change change)
{
struct kvm_memslots *slots;
- size_t old_size, new_size;
-
- old_size = sizeof(struct kvm_memslots) +
- (sizeof(struct kvm_memory_slot) * old->used_slots);
+ size_t new_size;
if (change == KVM_MR_CREATE)
- new_size = old_size + sizeof(struct kvm_memory_slot);
+ new_size = kvm_memslots_size(old->used_slots + 1);
else
- new_size = old_size;
+ new_size = kvm_memslots_size(old->used_slots);
slots = kvzalloc(new_size, GFP_KERNEL_ACCOUNT);
if (likely(slots))
- memcpy(slots, old, old_size);
+ kvm_copy_memslots(slots, old);
return slots;
}
--
2.31.1.751.gd2f1c929bd-goog
