On Wed, Oct 20, 2021 at 8:46 PM Michael Roth michael.roth@amd.com wrote:
On Mon, Oct 18, 2021 at 08:00:00AM -0700, Mingwei Zhang wrote:
+void vm_set_memory_encryption(struct kvm_vm *vm, bool enc_by_default, bool has_enc_bit,
uint8_t enc_bit)+{
vm->memcrypt.enabled = true;vm->memcrypt.enc_by_default = enc_by_default;vm->memcrypt.has_enc_bit = has_enc_bit;vm->memcrypt.enc_bit = enc_bit;+}
+struct sparsebit * +vm_get_encrypted_phy_pages(struct kvm_vm *vm, int slot, vm_paddr_t *gpa_start,
uint64_t *size)+{
struct userspace_mem_region *region;struct sparsebit *encrypted_phy_pages;if (!vm->memcrypt.enabled)return NULL;region = memslot2region(vm, slot);if (!region)return NULL;encrypted_phy_pages = sparsebit_alloc();sparsebit_copy(encrypted_phy_pages, region->encrypted_phy_pages);Do we have to make a copy for the sparsebit? Why not just return the pointer? By looking at your subsequent patches, I find that this data structure seems to be just read-only?
Yes, it's only intended to be used for read access. But I'll if I can enforce that without the need to use a copy.
Understood. Thanks for the clarification. Yeah, I think both making a copy and returning a const pointer should work. I will leave that to you then.
Thanks. -Mingwei