Make HostMemoryBackend::mr pointer and add pointee to HostMemoryBackend.
Initialize mr in host_memory_backend_memory_complete().
For restricted memfd memory backend to be able to use any host memory
backend.
No functional change, just add one pointer as indirection.
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com>
EPC (Enclave Page Cahe) is a specialized type of memory used by Intel
SGX (Software Guard Extensions). The SDM desribes EPC as:
The Enclave Page Cache (EPC) is the secure storage used to store
enclave pages when they are a part of an executing enclave. For an
EPC page, hardware performs additional access control checks to
restrict access to the page. After the current page access checks
and translations are performed, the hardware checks that the EPC
page is accessible to the program currently executing. Generally an
EPC page is only accessed by the owner of the executing enclave or
an instruction which is setting up an EPC page.
Because of its unique requirements, Linux manages EPC separately from
normal memory. Similar to memfd, the device /dev/sgx_vepc can be
opened to obtain a file descriptor which can in turn be used to mmap()
EPC memory.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20210719112136.57018-3-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>