Having code for the pkey_mprotect, pkey_alloc and pkey_free system
calls makes only sense if ARCH_HAS_PKEYS is selected. If not selected
these system calls will always return -ENOSPC or -EINVAL.
To simplify things and have less code generate the pkey system call
code only if ARCH_HAS_PKEYS is selected.
For architectures which have already wired up the system calls, but do
not select ARCH_HAS_PKEYS this will result in less generated code and
a different return code: the three system calls will now always return
-ENOSYS, using the cond_syscall mechanism.
For architectures which have not wired up the system calls less
unreachable code will be generated.
Signed-off-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
---
mm/mprotect.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/mm/mprotect.c b/mm/mprotect.c
index 11936526b08b..a06e91c4de29 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -484,6 +484,8 @@ SYSCALL_DEFINE3(mprotect, unsigned long, start, size_t, len,
return do_mprotect_pkey(start, len, prot, -1);
}
+#ifdef CONFIG_ARCH_HAS_PKEYS
+
SYSCALL_DEFINE4(pkey_mprotect, unsigned long, start, size_t, len,
unsigned long, prot, int, pkey)
{
@@ -534,3 +536,5 @@ SYSCALL_DEFINE1(pkey_free, int, pkey)
*/
return ret;
}
+
+#endif /* CONFIG_ARCH_HAS_PKEYS */
--
2.8.4
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>