[PATCH 4.9 57/69] nbd: fix 64-bit division

From: Greg Kroah-Hartman
Date: Wed Apr 19 2017 - 10:50:09 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Jens Axboe <axboe@xxxxxx>

commit e88f72cb9f54f6d244e55f629fe5e2f34ca6f9ed upstream.

We have this:

ERROR: "__aeabi_ldivmod" [drivers/block/nbd.ko] undefined!
ERROR: "__divdi3" [drivers/block/nbd.ko] undefined!
nbd.c:(.text+0x247c72): undefined reference to `__divdi3'

due to a recent commit, that did 64-bit division. Use the proper
divider function so that 32-bit compiles don't break.

Fixes: ef77b515243b ("nbd: use loff_t for blocksize and nbd_set_size args")
Signed-off-by: Jens Axboe <axboe@xxxxxx>
Cc: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/block/nbd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -648,7 +648,7 @@ static int __nbd_ioctl(struct block_devi

case NBD_SET_SIZE:
return nbd_size_set(nbd, bdev, nbd->blksize,
- arg / nbd->blksize);
+ div_s64(arg, nbd->blksize));

case NBD_SET_SIZE_BLOCKS:
return nbd_size_set(nbd, bdev, nbd->blksize, arg);