x86/sgx: Export sgx_encl_page_alloc()

Move sgx_encl_page_alloc() to encl.c and export it so that it can be
used in the implementation for support of adding pages to initialized
enclaves, which requires to allocate new enclave pages.

Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/57ae71b4ea17998467670232e12d6617b95c6811.1652137848.git.reinette.chatre@intel.com

diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c
index c6cac43..5e6a64d 100644 (file)
--- a/arch/x86/kernel/cpu/sgx/encl.c
+++ b/arch/x86/kernel/cpu/sgx/encl.c
@@ -887,6 +887,38 @@ int sgx_encl_test_and_clear_young(struct mm_struct *mm,
        return ret;
 }
 
+struct sgx_encl_page *sgx_encl_page_alloc(struct sgx_encl *encl,
+                                         unsigned long offset,
+                                         u64 secinfo_flags)
+{
+       struct sgx_encl_page *encl_page;
+       unsigned long prot;
+
+       encl_page = kzalloc(sizeof(*encl_page), GFP_KERNEL);
+       if (!encl_page)
+               return ERR_PTR(-ENOMEM);
+
+       encl_page->desc = encl->base + offset;
+       encl_page->encl = encl;
+
+       prot = _calc_vm_trans(secinfo_flags, SGX_SECINFO_R, PROT_READ)  |
+              _calc_vm_trans(secinfo_flags, SGX_SECINFO_W, PROT_WRITE) |
+              _calc_vm_trans(secinfo_flags, SGX_SECINFO_X, PROT_EXEC);
+
+       /*
+        * TCS pages must always RW set for CPU access while the SECINFO
+        * permissions are *always* zero - the CPU ignores the user provided
+        * values and silently overwrites them with zero permissions.
+        */
+       if ((secinfo_flags & SGX_SECINFO_PAGE_TYPE_MASK) == SGX_SECINFO_TCS)
+               prot |= PROT_READ | PROT_WRITE;
+
+       /* Calculate maximum of the VM flags for the page. */
+       encl_page->vm_max_prot_bits = calc_vm_prot_bits(prot, 0);
+
+       return encl_page;
+}
+
 /**
  * sgx_zap_enclave_ptes() - remove PTEs mapping the address from enclave
  * @encl: the enclave

diff --git a/arch/x86/kernel/cpu/sgx/encl.h b/arch/x86/kernel/cpu/sgx/encl.h
index b6b53c0..2cb58ab 100644 (file)
--- a/arch/x86/kernel/cpu/sgx/encl.h
+++ b/arch/x86/kernel/cpu/sgx/encl.h
@@ -112,6 +112,9 @@ int sgx_encl_get_backing(struct sgx_encl *encl, unsigned long page_index,
 void sgx_encl_put_backing(struct sgx_backing *backing);
 int sgx_encl_test_and_clear_young(struct mm_struct *mm,
                                  struct sgx_encl_page *page);
+struct sgx_encl_page *sgx_encl_page_alloc(struct sgx_encl *encl,
+                                         unsigned long offset,
+                                         u64 secinfo_flags);
 void sgx_zap_enclave_ptes(struct sgx_encl *encl, unsigned long addr);
 struct sgx_epc_page *sgx_alloc_va_page(void);
 unsigned int sgx_alloc_va_slot(struct sgx_va_page *va_page);

diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c
index 2df27dd..bb8cdb2 100644 (file)
--- a/arch/x86/kernel/cpu/sgx/ioctl.c
+++ b/arch/x86/kernel/cpu/sgx/ioctl.c
@@ -169,38 +169,6 @@ static long sgx_ioc_enclave_create(struct sgx_encl *encl, void __user *arg)
        return ret;
 }
 
-static struct sgx_encl_page *sgx_encl_page_alloc(struct sgx_encl *encl,
-                                                unsigned long offset,
-                                                u64 secinfo_flags)
-{
-       struct sgx_encl_page *encl_page;
-       unsigned long prot;
-
-       encl_page = kzalloc(sizeof(*encl_page), GFP_KERNEL);
-       if (!encl_page)
-               return ERR_PTR(-ENOMEM);
-
-       encl_page->desc = encl->base + offset;
-       encl_page->encl = encl;
-
-       prot = _calc_vm_trans(secinfo_flags, SGX_SECINFO_R, PROT_READ)  |
-              _calc_vm_trans(secinfo_flags, SGX_SECINFO_W, PROT_WRITE) |
-              _calc_vm_trans(secinfo_flags, SGX_SECINFO_X, PROT_EXEC);
-
-       /*
-        * TCS pages must always RW set for CPU access while the SECINFO
-        * permissions are *always* zero - the CPU ignores the user provided
-        * values and silently overwrites them with zero permissions.
-        */
-       if ((secinfo_flags & SGX_SECINFO_PAGE_TYPE_MASK) == SGX_SECINFO_TCS)
-               prot |= PROT_READ | PROT_WRITE;
-
-       /* Calculate maximum of the VM flags for the page. */
-       encl_page->vm_max_prot_bits = calc_vm_prot_bits(prot, 0);
-
-       return encl_page;
-}
-
 static int sgx_validate_secinfo(struct sgx_secinfo *secinfo)
 {
        u64 perm = secinfo->flags & SGX_SECINFO_PERMISSION_MASK;