Re: [PATCH v6 12/14] KVM: selftests: Add dirty ring buffer test

[Andrew Jones]

On Mon, Mar 09, 2020 at 06:25:29PM -0400, Peter Xu wrote:
> +void *vcpu_map_dirty_ring(struct kvm_vm *vm, uint32_t vcpuid)
> +{
> +	struct vcpu *vcpu;
> +	uint32_t size = vm->dirty_ring_size;
> +
> +	TEST_ASSERT(size > 0, "Should enable dirty ring first");
> +
> +	vcpu = vcpu_find(vm, vcpuid);
> +
> +	TEST_ASSERT(vcpu, "Cannot find vcpu %u", vcpuid);
> +
> +	if (!vcpu->dirty_gfns) {
> +		void *addr;
> +
> +		addr = mmap(NULL, size, PROT_READ,
> +			    MAP_PRIVATE, vcpu->fd,
> +			    vm->page_size * KVM_DIRTY_LOG_PAGE_OFFSET);
> +		TEST_ASSERT(addr == MAP_FAILED, "Dirty ring mapped private");
> +
> +		addr = mmap(NULL, size, PROT_READ | PROT_EXEC,
> +			    MAP_PRIVATE, vcpu->fd,
> +			    vm->page_size * KVM_DIRTY_LOG_PAGE_OFFSET);
> +		TEST_ASSERT(addr == MAP_FAILED, "Dirty ring mapped exec");
> +
> +		addr = mmap(NULL, size, PROT_READ | PROT_WRITE,
> +			    MAP_SHARED, vcpu->fd,
> +			    vm->page_size * KVM_DIRTY_LOG_PAGE_OFFSET);

No TEST_ASSERT for this mmap?

> +
> +		vcpu->dirty_gfns = addr;
> +		vcpu->dirty_gfns_count = size / sizeof(struct kvm_dirty_gfn);
> +	}
> +
> +	return vcpu->dirty_gfns;
> +}