summaryrefslogtreecommitdiff
path: root/include/uapi/linux/const.h
diff options
context:
space:
mode:
authorDavid Howells <dhowells@redhat.com>2012-10-13 13:46:48 +0400
committerDavid Howells <dhowells@redhat.com>2012-10-13 13:46:48 +0400
commit607ca46e97a1b6594b29647d98a32d545c24bdff (patch)
tree30f4c0784bfddb57332cdc0678bd06d1e77fa185 /include/uapi/linux/const.h
parent08cce05c5a91f5017f4edc9866cf026908c73f9f (diff)
downloadlinux-607ca46e97a1b6594b29647d98a32d545c24bdff.tar.xz
UAPI: (Scripted) Disintegrate include/linux
Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Kerrisk <mtk.manpages@gmail.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Dave Jones <davej@redhat.com>
Diffstat (limited to 'include/uapi/linux/const.h')
-rw-r--r--include/uapi/linux/const.h24
1 files changed, 24 insertions, 0 deletions
diff --git a/include/uapi/linux/const.h b/include/uapi/linux/const.h
new file mode 100644
index 000000000000..c22c707c455d
--- /dev/null
+++ b/include/uapi/linux/const.h
@@ -0,0 +1,24 @@
+/* const.h: Macros for dealing with constants. */
+
+#ifndef _LINUX_CONST_H
+#define _LINUX_CONST_H
+
+/* Some constant macros are used in both assembler and
+ * C code. Therefore we cannot annotate them always with
+ * 'UL' and other type specifiers unilaterally. We
+ * use the following macros to deal with this.
+ *
+ * Similarly, _AT() will cast an expression with a type in C, but
+ * leave it unchanged in asm.
+ */
+
+#ifdef __ASSEMBLY__
+#define _AC(X,Y) X
+#define _AT(T,X) X
+#else
+#define __AC(X,Y) (X##Y)
+#define _AC(X,Y) __AC(X,Y)
+#define _AT(T,X) ((T)(X))
+#endif
+
+#endif /* !(_LINUX_CONST_H) */