vkGetBufferMemoryRequirements

To determine the memory requirements for a buffer resource, call:

void vkGetBufferMemoryRequirements(
    VkDevice device,
    VkBuffer buffer,
    VkMemoryRequirements* pMemoryRequirements);

device is the logical device that owns the buffer.
buffer is the buffer to query.
pMemoryRequirements is a pointer to a VkMemoryRequirements structure in which the memory requirements of the buffer object are returned.

device must be a valid VkDevice handle

buffer must be a valid VkBuffer handle

pMemoryRequirements must be a valid pointer to a VkMemoryRequirements structure

buffer must have been created, allocated, or retrieved from device