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authorJo-Philipp Wich <jo@mein.io>2021-08-03 16:53:58 +0200
committerJo-Philipp Wich <jo@mein.io>2021-09-15 20:33:22 +0200
commitcbae3cba1964ebf367dd84524c6403a308302ace (patch)
treea48e590d190cf0a78b784c3ff337247fdf6faf05 /include/linux/const.h
parente6dd389d06d9d33195afcf77a740df072298959e (diff)
lib: introduce Linux route netlink binding
Signed-off-by: Jo-Philipp Wich <jo@mein.io>
Diffstat (limited to 'include/linux/const.h')
-rw-r--r--include/linux/const.h36
1 files changed, 36 insertions, 0 deletions
diff --git a/include/linux/const.h b/include/linux/const.h
new file mode 100644
index 0000000..5e48987
--- /dev/null
+++ b/include/linux/const.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* 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
+
+#define _UL(x) (_AC(x, UL))
+#define _ULL(x) (_AC(x, ULL))
+
+#define _BITUL(x) (_UL(1) << (x))
+#define _BITULL(x) (_ULL(1) << (x))
+
+#define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
+#define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
+
+#define __KERNEL_DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
+
+#endif /* _LINUX_CONST_H */