From ddc12f2a12917c10b0deb0928f0560bffb7729ec Mon Sep 17 00:00:00 2001 From: Ben Gardon Date: Tue, 18 May 2021 10:34:10 -0700 Subject: [PATCH] KVM: mmu: Refactor memslot copy 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 Signed-off-by: Ben Gardon Message-Id: <20210518173414.450044-4-bgardon@google.com> Signed-off-by: Paolo Bonzini --- 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 6a6bc7af0e28..d65be9461493 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1307,6 +1307,18 @@ 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 @@ -1316,19 +1328,16 @@ 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; } -- 2.11.0