[PATCH net-next v3 1/4] uapi: define DIV_ROUND_UP for userland

From: Nicolas Dichtel
Date: Fri Mar 04 2016 - 05:58:52 EST


DIV_ROUND_UP is defined in linux/kernel.h only for the kernel.
When ethtool.h is included by a userland app, we got the following error:

include/linux/ethtool.h:1218:8: error: variably modified 'queue_mask' at file scope
__u32 queue_mask[DIV_ROUND_UP(MAX_NUM_QUEUE, 32)];
^

Let's add a common definition in uapi and use it everywhere.

Fixes: ac2c7ad0e5d6 ("net/ethtool: introduce a new ioctl for per queue setting")
CC: Kan Liang <kan.liang@xxxxxxxxx>
Suggested-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@xxxxxxxxx>
---
include/linux/kernel.h | 2 +-
include/uapi/linux/ethtool.h | 3 ++-
include/uapi/linux/kernel.h | 1 +
include/uapi/linux/mroute6.h | 9 ++-------
4 files changed, 6 insertions(+), 9 deletions(-)

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index f31638c6e873..ac1923957236 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -64,7 +64,7 @@
#define round_down(x, y) ((x) & ~__round_mask(x, y))

#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
-#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
+#define DIV_ROUND_UP __KERNEL_DIV_ROUND_UP
#define DIV_ROUND_UP_ULL(ll,d) \
({ unsigned long long _tmp = (ll)+(d)-1; do_div(_tmp, d); _tmp; })

diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 37fd6dc33de4..9c22249ebf35 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -13,6 +13,7 @@
#ifndef _UAPI_LINUX_ETHTOOL_H
#define _UAPI_LINUX_ETHTOOL_H

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

@@ -1215,7 +1216,7 @@ enum ethtool_sfeatures_retval_bits {
struct ethtool_per_queue_op {
__u32 cmd;
__u32 sub_command;
- __u32 queue_mask[DIV_ROUND_UP(MAX_NUM_QUEUE, 32)];
+ __u32 queue_mask[__KERNEL_DIV_ROUND_UP(MAX_NUM_QUEUE, 32)];
char data[];
};

diff --git a/include/uapi/linux/kernel.h b/include/uapi/linux/kernel.h
index 321e399457f5..466073f0ce46 100644
--- a/include/uapi/linux/kernel.h
+++ b/include/uapi/linux/kernel.h
@@ -9,5 +9,6 @@
#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_KERNEL_H */
diff --git a/include/uapi/linux/mroute6.h b/include/uapi/linux/mroute6.h
index ce91215cf7e6..5062fb5751e1 100644
--- a/include/uapi/linux/mroute6.h
+++ b/include/uapi/linux/mroute6.h
@@ -1,6 +1,7 @@
#ifndef _UAPI__LINUX_MROUTE6_H
#define _UAPI__LINUX_MROUTE6_H

+#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/sockios.h>

@@ -46,14 +47,8 @@ typedef unsigned short mifi_t;
typedef __u32 if_mask;
#define NIFBITS (sizeof(if_mask) * 8) /* bits per mask */

-#if !defined(__KERNEL__)
-#if !defined(DIV_ROUND_UP)
-#define DIV_ROUND_UP(x,y) (((x) + ((y) - 1)) / (y))
-#endif
-#endif
-
typedef struct if_set {
- if_mask ifs_bits[DIV_ROUND_UP(IF_SETSIZE, NIFBITS)];
+ if_mask ifs_bits[__KERNEL_DIV_ROUND_UP(IF_SETSIZE, NIFBITS)];
} if_set;

#define IF_SET(n, p) ((p)->ifs_bits[(n)/NIFBITS] |= (1 << ((n) % NIFBITS)))
--
2.4.2