From: Vignesh Babu BM <vignesh.babu@wipro.com>
Date: Tue, 8 May 2007 07:24:32 +0000 (-0700)
Subject: is_power_of_2 in fs/block_dev.c
X-Git-Tag: v2.6.22-rc1~783
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1368c4f2482c9e06bcb297217433818b171cc9e3;p=linux-2.6

is_power_of_2 in fs/block_dev.c

Replace (n & (n-1)) in the context of power of 2 checks with is_power_of_2

Signed-off-by: vignesh babu <vignesh.babu@wipro.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/fs/block_dev.c b/fs/block_dev.c
index f02b7bdd98..7428992408 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -22,6 +22,7 @@
 #include <linux/mount.h>
 #include <linux/uio.h>
 #include <linux/namei.h>
+#include <linux/log2.h>
 #include <asm/uaccess.h>
 #include "internal.h"
 
@@ -67,7 +68,7 @@ static void kill_bdev(struct block_device *bdev)
 int set_blocksize(struct block_device *bdev, int size)
 {
 	/* Size must be a power of two, and between 512 and PAGE_SIZE */
-	if (size > PAGE_SIZE || size < 512 || (size & (size-1)))
+	if (size > PAGE_SIZE || size < 512 || !is_power_of_2(size))
 		return -EINVAL;
 
 	/* Size cannot be smaller than the size supported by the device */