[RFC PATCH 02/11] x86/sgx: Provide VA page non-NULL owner

[Cathy Zhang <cathy.zhang@xxxxxxxxx>]

Provide non-NULL owner for VA page, which tells that the EPC page is
allocated for use.

Signed-off-by: Cathy Zhang <cathy.zhang@xxxxxxxxx>
---
 arch/x86/kernel/cpu/sgx/encl.h  | 2 +-
 arch/x86/kernel/cpu/sgx/sgx.h   | 2 +-
 arch/x86/kernel/cpu/sgx/encl.c  | 5 +++--
 arch/x86/kernel/cpu/sgx/ioctl.c | 2 +-
 4 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/sgx/encl.h b/arch/x86/kernel/cpu/sgx/encl.h
index 1b6ce1da7c92..1807a7f55065 100644
--- a/arch/x86/kernel/cpu/sgx/encl.h
+++ b/arch/x86/kernel/cpu/sgx/encl.h
@@ -114,7 +114,7 @@ void sgx_encl_put_backing(struct sgx_backing *backing, bool do_write);
 int sgx_encl_test_and_clear_young(struct mm_struct *mm,
 				  struct sgx_encl_page *page);
 void sgx_zap_enclave_ptes(struct sgx_encl *encl, unsigned long addr);
-struct sgx_epc_page *sgx_alloc_va_page(void);
+struct sgx_epc_page *sgx_alloc_va_page(struct sgx_va_page *va_page);
 unsigned int sgx_alloc_va_slot(struct sgx_va_page *va_page);
 void sgx_free_va_slot(struct sgx_va_page *va_page, unsigned int offset);
 bool sgx_va_page_full(struct sgx_va_page *va_page);
diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h
index dc8cb58100e3..e627c42a6eec 100644
--- a/arch/x86/kernel/cpu/sgx/sgx.h
+++ b/arch/x86/kernel/cpu/sgx/sgx.h
@@ -33,7 +33,7 @@ struct sgx_epc_page {
 	unsigned int section;
 	u16 flags;
 	u16 poison;
-	struct sgx_encl_page *owner;
+	void *owner;
 	struct list_head list;
 };
 
diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c
index d2b428992910..e08c59a049d3 100644
--- a/arch/x86/kernel/cpu/sgx/encl.c
+++ b/arch/x86/kernel/cpu/sgx/encl.c
@@ -990,6 +990,7 @@ void sgx_zap_enclave_ptes(struct sgx_encl *encl, unsigned long addr)
 
 /**
  * sgx_alloc_va_page() - Allocate a Version Array (VA) page
+ * @va_page:	struct sgx_va_page connected to this VA page
  *
  * Allocate a free EPC page and convert it to a Version Array (VA) page.
  *
@@ -997,12 +998,12 @@ void sgx_zap_enclave_ptes(struct sgx_encl *encl, unsigned long addr)
  *   a VA page,
  *   -errno otherwise
  */
-struct sgx_epc_page *sgx_alloc_va_page(void)
+struct sgx_epc_page *sgx_alloc_va_page(struct sgx_va_page *va_page)
 {
 	struct sgx_epc_page *epc_page;
 	int ret;
 
-	epc_page = sgx_alloc_epc_page(NULL, true);
+	epc_page = sgx_alloc_epc_page(va_page, true);
 	if (IS_ERR(epc_page))
 		return ERR_CAST(epc_page);
 
diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c
index da3b569a10bd..9eb429aeb319 100644
--- a/arch/x86/kernel/cpu/sgx/ioctl.c
+++ b/arch/x86/kernel/cpu/sgx/ioctl.c
@@ -30,7 +30,7 @@ struct sgx_va_page *sgx_encl_grow(struct sgx_encl *encl)
 		if (!va_page)
 			return ERR_PTR(-ENOMEM);
 
-		va_page->epc_page = sgx_alloc_va_page();
+		va_page->epc_page = sgx_alloc_va_page(va_page);
 		if (IS_ERR(va_page->epc_page)) {
 			err = ERR_CAST(va_page->epc_page);
 			kfree(va_page);
-- 
2.17.1