linux-kernel - [PATCH] nbd: use correct div

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Date:	Sat,  5 Mar 2016 00:49:31 +0100
From:	Arnd Bergmann <arnd@...db.de>
To:	Jens Axboe <axboe@...com>, Markus Pargmann <mpa@...gutronix.de>
Cc:	Arnd Bergmann <arnd@...db.de>, nbd-general@...ts.sourceforge.net,
	linux-kernel@...r.kernel.org
Subject: [PATCH] nbd: use correct div_s64 helper

The do_div() macro now checks its arguments for the correct type,
and refuses anything other than u64, so we get a warning about
nbd_ioctl passing in an loff_t:

drivers/block/nbd.c: In function '__nbd_ioctl':
drivers/block/nbd.c:757:77: error: comparison of distinct pointer types lacks a cast [-Werror]

This changes the nbd code to use div_s64() instead, which takes
a signed argument.

Signed-off-by: Arnd Bergmann <arnd@...db.de>
Fixes: 37091fdd831f ("nbd: Create size change events for userspace")
---
 drivers/block/nbd.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index f6b51d76e578..08afbc7a2bb8 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -753,8 +753,7 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
 	}
 
 	case NBD_SET_BLKSIZE: {
-		loff_t bsize = nbd->bytesize;
-		do_div(bsize, arg);
+		loff_t bsize = div_s64(nbd->bytesize, arg);
 
 		return nbd_size_set(nbd, bdev, arg, bsize);
 	}
-- 
2.7.0