On Mon, Jun 03, 2019 at 01:14:45PM -0700, Dave Hansen wrote:

On 5/31/19 4:31 PM, Sean Christopherson wrote:

quoted

-struct sgx_enclave_add_page {
+struct sgx_enclave_add_pages {
 	__u64	addr;
 	__u64	src;
 	__u64	secinfo;
+	__u32	nr_pages;
 	__u16	mrmask;
 } __attribute__((__packed__));

IMNHO this follows a user interface anti-pattern: exposing page sizes
where not strictly required.

Think of how this would look to an application if page size was
variable.  With this interface, they always need to scale their
operations by page size instead of just aligning it.

I briefly considered taking size in bytes, but I took a shortcut because
EPC pages are architecturally defined to be 4k sized and aligned.  That
being said, I don't necessarily disagree, especially if nr_pages isn't
squeezed into a u32.
 

BTW, why is nr_pages a u32?  Do we never envision a case where you can
add more than 4TB of memory to an enclave? ;)

Heh, fair enough.  IIRC, a while back someone posted about having problems
building a 512gb enclave in a 92mb EPC...

How about this for the intermediate patch:

	struct sgx_enclave_add_region {
		__u64	addr;
		__u64	src;
		__u64	size;
		__u64	secinfo;
		__u16	mrmask;
		__u16	reserved16;
		__u32	reserved;
	}

and with the flags field:

	struct sgx_enclave_add_region {
		__u64	addr;
		__u64	src;
		__u64	size;
		__u64	secinfo;
		__u16	mrmask;
		__u16	flags;
		__u32	reserved;
	}