linux-kernel - [PATCH] x86/xen: Use DIV_ROUND

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20160629150038.GA13956@amitoj-Inspiron-3542>
Date:	Wed, 29 Jun 2016 20:30:38 +0530
From:	Amitoj Kaur Chawla <amitoj1606@...il.com>
To:	boris.ostrovsky@...cle.com, david.vrabel@...rix.com,
	jgross@...e.com, tglx@...utronix.de, mingo@...hat.com,
	hpa@...or.com, x86@...nel.org, xen-devel@...ts.xenproject.org,
	linux-kernel@...r.kernel.org
Cc:	julia.lawall@...6.fr
Subject: [PATCH] x86/xen: Use DIV_ROUND_UP

The kernel.h macro DIV_ROUND_UP performs the computation
(((n) + (d) - 1) /(d)) but is perhaps more readable.

The Coccinelle script used to make this change is as follows:
@haskernel@
@@

#include <linux/kernel.h>

@depends on haskernel@
expression n,d;
@@

(
- (n + d - 1) / d
+ DIV_ROUND_UP(n,d)
|
- (n + (d - 1)) / d
+ DIV_ROUND_UP(n,d)
)

Signed-off-by: Amitoj Kaur Chawla <amitoj1606@...il.com>
---
 arch/x86/xen/enlighten.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 880862c..6847512 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -591,7 +591,7 @@ static void xen_load_gdt(const struct desc_ptr *dtr)
 {
 	unsigned long va = dtr->address;
 	unsigned int size = dtr->size + 1;
-	unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
+	unsigned pages = DIV_ROUND_UP(size, PAGE_SIZE);
 	unsigned long frames[pages];
 	int f;
 
@@ -640,7 +640,7 @@ static void __init xen_load_gdt_boot(const struct desc_ptr *dtr)
 {
 	unsigned long va = dtr->address;
 	unsigned int size = dtr->size + 1;
-	unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
+	unsigned pages = DIV_ROUND_UP(size, PAGE_SIZE);
 	unsigned long frames[pages];
 	int f;
 
-- 
1.9.1