add mlock2 linux syscall wrapper

mlock2 syscall was added in linux v4.4 and glibc has api for it.
It falls back to mlock in case of flags==0, so that case works
even on older kernels.

MLOCK_ONFAULT is moved under _GNU_SOURCE following glibc.

1 files changed, 10 insertions, 0 deletions

diff --git a/src/linux/mlock2.c b/src/linux/mlock2.c
new file mode 100644
index 00000000..10132742
--- /dev/null
+++ b/src/linux/mlock2.c
@@ -0,0 +1,10 @@
+#define _GNU_SOURCE 1
+#include <sys/mman.h>
+#include "syscall.h"
+
+int mlock2(const void *addr, size_t len, unsigned flags)
+{
+	if (flags == 0)
+		return mlock(addr, len);
+	return syscall(SYS_mlock2, addr, len, flags);
+}