[PATCH 4/9] linux/const.h: Upgrade & Merge vDSO and uAPI

Pierre-Clément Tosi ptosi at google.com
Wed Mar 16 16:39:43 CET 2022

Import the header from version 5.16 of the kernel:

    commit df0cc57e057f18e44dac8e6c18aba47ab53202f9

Inline <vdso/const.h> and <uapi/linux/const.h>. This is wrapped in
"#ifndef __UBOOT__/#include/#else/{inline}" to better document the
origin of the code being added to the U-Boot header (but not present in
the original header) and make diff tools happier when comparing the file
with its reference, which should be useful when porting future changes
from the Linux header and/or if we decide to also import those included
headers into the U-Boot codebase.

Signed-off-by: Pierre-Clément Tosi <ptosi at google.com>
Cc: Simon Glass <sjg at chromium.org>
Cc: Tom Rini <trini at konsulko.com>
 include/linux/const.h | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/include/linux/const.h b/include/linux/const.h
index 379c889232..3e3803d767 100644
--- a/include/linux/const.h
+++ b/include/linux/const.h
@@ -2,8 +2,13 @@
 #ifndef _LINUX_CONST_H
 #define _LINUX_CONST_H
-/* const.h: Macros for dealing with constants.  */
+#ifndef __UBOOT__
+#include <vdso/const.h>
+#ifndef __UBOOT__
+#include <uapi/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
@@ -28,7 +33,22 @@
 #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))
 #define UL(x)		(_UL(x))
 #define ULL(x)		(_ULL(x))
+ * This returns a constant expression while determining if an argument is
+ * a constant expression, most importantly without evaluating the argument.
+ * Glory to Martin Uecker <Martin.Uecker at med.uni-goettingen.de>
+ */
+#define __is_constexpr(x) \
+	(sizeof(int) == sizeof(*(8 ? ((void *)((long)(x) * 0l)) : (int *)8)))
 #endif /* _LINUX_CONST_H */

More information about the U-Boot mailing list