KVM: Move setting of memslot into helper routine (cf47f50b) · Commits · 戴 / test

virt/kvm/kvm_main.c

+63 −43

Original line number	Original line	Diff line number	Diff line
	@@ -983,6 +983,66 @@ static struct kvm_memslots install_new_memslots(struct kvm kvm,
	return old_memslots;		return old_memslots;
	}		}

			static int kvm_set_memslot(struct kvm *kvm,
			const struct kvm_userspace_memory_region *mem,
			const struct kvm_memory_slot *old,
			struct kvm_memory_slot *new, int as_id,
			enum kvm_mr_change change)
			{
			struct kvm_memory_slot *slot;
			struct kvm_memslots *slots;
			int r;

			slots = kvzalloc(sizeof(struct kvm_memslots), GFP_KERNEL_ACCOUNT);
			if (!slots)
			return -ENOMEM;
			memcpy(slots, __kvm_memslots(kvm, as_id), sizeof(struct kvm_memslots));

			if (change == KVM_MR_DELETE \|\| change == KVM_MR_MOVE) {
			/*
			* Note, the INVALID flag needs to be in the appropriate entry
			* in the freshly allocated memslots, not in @old or @new.
			*/
			slot = id_to_memslot(slots, old->id);
			slot->flags \|= KVM_MEMSLOT_INVALID;

			/*
			* We can re-use the old memslots, the only difference from the
			* newly installed memslots is the invalid flag, which will get
			* dropped by update_memslots anyway. We'll also revert to the
			* old memslots if preparing the new memory region fails.
			*/
			slots = install_new_memslots(kvm, as_id, slots);

			/* From this point no new shadow pages pointing to a deleted,
			* or moved, memslot will be created.
			*
			* validation of sp->gfn happens in:
			* - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
			* - kvm_is_visible_gfn (mmu_check_root)
			*/
			kvm_arch_flush_shadow_memslot(kvm, slot);
			}

			r = kvm_arch_prepare_memory_region(kvm, new, mem, change);
			if (r)
			goto out_slots;

			update_memslots(slots, new, change);
			slots = install_new_memslots(kvm, as_id, slots);

			kvm_arch_commit_memory_region(kvm, mem, old, new, change);

			kvfree(slots);
			return 0;

			out_slots:
			if (change == KVM_MR_DELETE \|\| change == KVM_MR_MOVE)
			slots = install_new_memslots(kvm, as_id, slots);
			kvfree(slots);
			return r;
			}

	/*		/*
	* Allocate some memory and give it an address in the guest physical address		* Allocate some memory and give it an address in the guest physical address
	* space.		* space.
	@@ -999,7 +1059,6 @@ int __kvm_set_memory_region(struct kvm *kvm,
	unsigned long npages;		unsigned long npages;
	struct kvm_memory_slot *slot;		struct kvm_memory_slot *slot;
	struct kvm_memory_slot old, new;		struct kvm_memory_slot old, new;
	struct kvm_memslots *slots;
	int as_id, id;		int as_id, id;
	enum kvm_mr_change change;		enum kvm_mr_change change;

	@@ -1086,58 +1145,19 @@ int __kvm_set_memory_region(struct kvm *kvm,
	return r;		return r;
	}		}

	slots = kvzalloc(sizeof(struct kvm_memslots), GFP_KERNEL_ACCOUNT);
	if (!slots) {
	r = -ENOMEM;
	goto out_bitmap;
	}
	memcpy(slots, __kvm_memslots(kvm, as_id), sizeof(struct kvm_memslots));

	if ((change == KVM_MR_DELETE) \|\| (change == KVM_MR_MOVE)) {
	slot = id_to_memslot(slots, id);
	slot->flags \|= KVM_MEMSLOT_INVALID;

	/*
	* We can re-use the old memslots, the only difference from the
	* newly installed memslots is the invalid flag, which will get
	* dropped by update_memslots anyway. We'll also revert to the
	* old memslots if preparing the new memory region fails.
	*/
	slots = install_new_memslots(kvm, as_id, slots);

	/* From this point no new shadow pages pointing to a deleted,
	* or moved, memslot will be created.
	*
	* validation of sp->gfn happens in:
	* - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
	* - kvm_is_visible_gfn (mmu_check_root)
	*/
	kvm_arch_flush_shadow_memslot(kvm, slot);
	}

	r = kvm_arch_prepare_memory_region(kvm, &new, mem, change);
	if (r)
	goto out_slots;

	/* actual memory is freed via old in kvm_free_memslot below */		/* actual memory is freed via old in kvm_free_memslot below */
	if (change == KVM_MR_DELETE) {		if (change == KVM_MR_DELETE) {
	new.dirty_bitmap = NULL;		new.dirty_bitmap = NULL;
	memset(&new.arch, 0, sizeof(new.arch));		memset(&new.arch, 0, sizeof(new.arch));
	}		}

	update_memslots(slots, &new, change);		r = kvm_set_memslot(kvm, mem, &old, &new, as_id, change);
	slots = install_new_memslots(kvm, as_id, slots);		if (r)
			goto out_bitmap;
	kvm_arch_commit_memory_region(kvm, mem, &old, &new, change);

	kvm_free_memslot(kvm, &old, &new);		kvm_free_memslot(kvm, &old, &new);
	kvfree(slots);
	return 0;		return 0;

	out_slots:
	if (change == KVM_MR_DELETE \|\| change == KVM_MR_MOVE)
	slots = install_new_memslots(kvm, as_id, slots);
	kvfree(slots);
	out_bitmap:		out_bitmap:
	if (new.dirty_bitmap && !old.dirty_bitmap)		if (new.dirty_bitmap && !old.dirty_bitmap)
	kvm_destroy_dirty_bitmap(&new);		kvm_destroy_dirty_bitmap(&new);

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