[PATCH for_v23 1/7] x86/sgx: Modify ADD_PAGE ioctl to take offset instead of full address

[Sean Christopherson <sean.j.christopherson@xxxxxxxxx>]

Change SGX_IOC_ENCLAVE_ADD_PAGE to take the target page as an offset
instead of a full address now that the API no longer uses the address to
find the target enclave.

Suggested-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
---
 arch/x86/include/uapi/asm/sgx.h |  4 ++--
 arch/x86/kernel/cpu/sgx/ioctl.c | 10 +++++-----
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/x86/include/uapi/asm/sgx.h b/arch/x86/include/uapi/asm/sgx.h
index 8f4660e07f6b..67583b046af1 100644
--- a/arch/x86/include/uapi/asm/sgx.h
+++ b/arch/x86/include/uapi/asm/sgx.h
@@ -31,14 +31,14 @@ struct sgx_enclave_create  {
 /**
  * struct sgx_enclave_add_page - parameter structure for the
  *                               %SGX_IOC_ENCLAVE_ADD_PAGE ioctl
- * @addr:	address within the ELRANGE
+ * @offset:	page offset within the enclave
  * @src:	address for the page data
  * @secinfo:	address for the SECINFO data
  * @mrmask:	bitmask for the measured 256 byte chunks
  * @reserved:	reserved for future use
  */
 struct sgx_enclave_add_page {
-	__u64	addr;
+	__u64	offset;
 	__u64	src;
 	__u64	secinfo;
 	__u16	mrmask;
diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c
index 75f868bad3ea..f407dd35f9e3 100644
--- a/arch/x86/kernel/cpu/sgx/ioctl.c
+++ b/arch/x86/kernel/cpu/sgx/ioctl.c
@@ -113,7 +113,7 @@ static int sgx_validate_secs(const struct sgx_secs *secs,
 }
 
 static struct sgx_encl_page *sgx_encl_page_alloc(struct sgx_encl *encl,
-						 unsigned long addr,
+						 unsigned long offset,
 						 u64 secinfo_flags)
 {
 	struct sgx_encl_page *encl_page;
@@ -123,7 +123,7 @@ static struct sgx_encl_page *sgx_encl_page_alloc(struct sgx_encl *encl,
 	if (!encl_page)
 		return ERR_PTR(-ENOMEM);
 
-	encl_page->desc = addr;
+	encl_page->desc = encl->base + offset;
 	encl_page->encl = encl;
 
 	prot = _calc_vm_trans(secinfo_flags, SGX_SECINFO_R, PROT_READ)  |
@@ -368,7 +368,7 @@ static int sgx_encl_add_page(struct sgx_encl *encl,
 	struct sgx_va_page *va_page;
 	int ret;
 
-	encl_page = sgx_encl_page_alloc(encl, addp->addr, secinfo->flags);
+	encl_page = sgx_encl_page_alloc(encl, addp->offset, secinfo->flags);
 	if (IS_ERR(encl_page))
 		return PTR_ERR(encl_page);
 
@@ -485,11 +485,11 @@ static long sgx_ioc_enclave_add_page(struct sgx_encl *encl, void __user *arg)
 	if (copy_from_user(&addp, arg, sizeof(addp)))
 		return -EFAULT;
 
-	if (!IS_ALIGNED(addp.addr, PAGE_SIZE) ||
+	if (!IS_ALIGNED(addp.offset, PAGE_SIZE) ||
 	    !IS_ALIGNED(addp.src, PAGE_SIZE))
 		return -EINVAL;
 
-	if (addp.addr < encl->base || addp.addr - encl->base >= encl->size)
+	if (addp.offset >= encl->size)
 		return -EINVAL;
 
 	if (copy_from_user(&secinfo, (void __user *)addp.secinfo,
-- 
2.22.0