X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=wrapper%2Fsplice.c;h=282bd863e2cb849ec57ec4336c43539d7a495858;hb=e12ef7eee8f880aa30eeb1998428282f1414bea5;hp=44a4d6b87b2b8062b571ed6270b4556006e8572a;hpb=9f36eaed6f91d5897924b551b44d1edd8cee00e2;p=lttng-modules.git

diff --git a/wrapper/splice.c b/wrapper/splice.c
index 44a4d6b8..282bd863 100644
--- a/wrapper/splice.c
+++ b/wrapper/splice.c
@@ -4,12 +4,15 @@
  *
  * wrapper around splice_to_pipe. Using KALLSYMS to get its address when
  * available, else we need to have a kernel that exports this function to GPL
- * modules.
+ * modules. The export was introduced in kernel 4.2.
  *
  * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  */
 
-#ifdef CONFIG_KALLSYMS
+#include <lttng-kernel-version.h>
+
+#if (defined(CONFIG_KALLSYMS) \
+	&& (LINUX_VERSION_CODE < KERNEL_VERSION(4,2,0)))
 
 #include <linux/kallsyms.h>
 #include <linux/fs.h>
@@ -33,6 +36,21 @@ ssize_t wrapper_splice_to_pipe(struct pipe_inode_info *pipe,
 	}
 }
 
+/*
+ * Canary function to check for 'splice_to_pipe()' at compile time.
+ *
+ * From 'include/linux/splice.h':
+ *
+ *   extern ssize_t splice_to_pipe(struct pipe_inode_info *,
+ *                                 struct splice_pipe_desc *spd);
+ */
+__attribute__((unused)) static
+ssize_t __canary__splice_to_pipe(struct pipe_inode_info *pipe,
+				struct splice_pipe_desc *spd)
+{
+	return splice_to_pipe(pipe, spd);
+}
+
 #else
 
 #include <linux/fs.h>