[PATCH v3 1/1] uapi: Move constants from <linux/kernel.h> to <linux/const.h>

From: Petr Vorel
Date: Thu Oct 15 2020 - 15:00:26 EST


and include <linux/const.h> in UAPI headers instead of <linux/kernel.h>.

The reason is to avoid indirect <linux/sysinfo.h> include when using
some network headers: <linux/netlink.h> or others -> <linux/kernel.h>
-> <linux/sysinfo.h>.

This indirect include causes on MUSL redefinition of struct sysinfo when
included both <sys/sysinfo.h> and some of UAPI headers:

In file included from x86_64-buildroot-linux-musl/sysroot/usr/include/linux/kernel.h:5,
from x86_64-buildroot-linux-musl/sysroot/usr/include/linux/netlink.h:5,
from ../include/tst_netlink.h:14,
from tst_crypto.c:13:
x86_64-buildroot-linux-musl/sysroot/usr/include/linux/sysinfo.h:8:8: error: redefinition of ‘struct sysinfo’
struct sysinfo {
^~~~~~~
In file included from ../include/tst_safe_macros.h:15,
from ../include/tst_test.h:93,
from tst_crypto.c:11:
x86_64-buildroot-linux-musl/sysroot/usr/include/sys/sysinfo.h:10:8: note: originally defined here

Suggested-by: Rich Felker <dalias@xxxxxxxxxx>
Signed-off-by: Petr Vorel <petr.vorel@xxxxxxxxx>
---
Changes v2->v3:
* Move things to <linux/const.h> instead of creating new header
<linux/align.h>.

Kind regards,
Petr

include/uapi/linux/const.h | 5 +++++
include/uapi/linux/ethtool.h | 2 +-
include/uapi/linux/kernel.h | 9 +--------
include/uapi/linux/lightnvm.h | 2 +-
include/uapi/linux/mroute6.h | 2 +-
include/uapi/linux/netfilter/x_tables.h | 2 +-
include/uapi/linux/netlink.h | 2 +-
include/uapi/linux/sysctl.h | 2 +-
8 files changed, 12 insertions(+), 14 deletions(-)

diff --git a/include/uapi/linux/const.h b/include/uapi/linux/const.h
index 5ed721ad5b19..af2a44c08683 100644
--- a/include/uapi/linux/const.h
+++ b/include/uapi/linux/const.h
@@ -28,4 +28,9 @@
#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 /* _UAPI_LINUX_CONST_H */
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index b4f2d134e713..0a9cced74e6d 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -14,7 +14,7 @@
#ifndef _UAPI_LINUX_ETHTOOL_H
#define _UAPI_LINUX_ETHTOOL_H

-#include <linux/kernel.h>
+#include <linux/const.h>
#include <linux/types.h>
#include <linux/if_ether.h>

diff --git a/include/uapi/linux/kernel.h b/include/uapi/linux/kernel.h
index 0ff8f7477847..fadf2db71fe8 100644
--- a/include/uapi/linux/kernel.h
+++ b/include/uapi/linux/kernel.h
@@ -3,13 +3,6 @@
#define _UAPI_LINUX_KERNEL_H

#include <linux/sysinfo.h>
-
-/*
- * 'kernel.h' contains some often-used function prototypes etc
- */
-#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))
+#include <linux/const.h>

#endif /* _UAPI_LINUX_KERNEL_H */
diff --git a/include/uapi/linux/lightnvm.h b/include/uapi/linux/lightnvm.h
index f9a1be7fc696..ead2e72e5c88 100644
--- a/include/uapi/linux/lightnvm.h
+++ b/include/uapi/linux/lightnvm.h
@@ -21,7 +21,7 @@
#define _UAPI_LINUX_LIGHTNVM_H

#ifdef __KERNEL__
-#include <linux/kernel.h>
+#include <linux/const.h>
#include <linux/ioctl.h>
#else /* __KERNEL__ */
#include <stdio.h>
diff --git a/include/uapi/linux/mroute6.h b/include/uapi/linux/mroute6.h
index c36177a86516..a1fd6173e2db 100644
--- a/include/uapi/linux/mroute6.h
+++ b/include/uapi/linux/mroute6.h
@@ -2,7 +2,7 @@
#ifndef _UAPI__LINUX_MROUTE6_H
#define _UAPI__LINUX_MROUTE6_H

-#include <linux/kernel.h>
+#include <linux/const.h>
#include <linux/types.h>
#include <linux/sockios.h>
#include <linux/in6.h> /* For struct sockaddr_in6. */
diff --git a/include/uapi/linux/netfilter/x_tables.h b/include/uapi/linux/netfilter/x_tables.h
index a8283f7dbc51..b8c6bb233ac1 100644
--- a/include/uapi/linux/netfilter/x_tables.h
+++ b/include/uapi/linux/netfilter/x_tables.h
@@ -1,7 +1,7 @@
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef _UAPI_X_TABLES_H
#define _UAPI_X_TABLES_H
-#include <linux/kernel.h>
+#include <linux/const.h>
#include <linux/types.h>

#define XT_FUNCTION_MAXNAMELEN 30
diff --git a/include/uapi/linux/netlink.h b/include/uapi/linux/netlink.h
index eac8a6a648ea..7ba6d3b9cdec 100644
--- a/include/uapi/linux/netlink.h
+++ b/include/uapi/linux/netlink.h
@@ -2,7 +2,7 @@
#ifndef _UAPI__LINUX_NETLINK_H
#define _UAPI__LINUX_NETLINK_H

-#include <linux/kernel.h>
+#include <linux/const.h>
#include <linux/socket.h> /* for __kernel_sa_family_t */
#include <linux/types.h>

diff --git a/include/uapi/linux/sysctl.h b/include/uapi/linux/sysctl.h
index 27c1ed2822e6..458179df9b27 100644
--- a/include/uapi/linux/sysctl.h
+++ b/include/uapi/linux/sysctl.h
@@ -23,7 +23,7 @@
#ifndef _UAPI_LINUX_SYSCTL_H
#define _UAPI_LINUX_SYSCTL_H

-#include <linux/kernel.h>
+#include <linux/const.h>
#include <linux/types.h>
#include <linux/compiler.h>

--
2.28.0