The snapshot code validates the snapshot chunksize against the device block
size. Since the block size is usually a power of 2 we don't need to use modulo
here which would let the compiler emit a call to __umoddi3(). Therefore this
patch changes to the test to use a bitmask instead.
Signed-off-by: Jan Blunck <jblunck@xxxxxxx>
---
drivers/md/dm-snap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -397,7 +397,7 @@ static int set_chunk_size(struct dm_snap
}
/* Validate the chunk size against the device block size */
- if (chunk_size % (bdev_hardsect_size(s->cow->bdev) >> 9)) {
+ if (chunk_size & ((bdev_hardsect_size(s->cow->bdev) >> 9) - 1)) {
*error = "Chunk size is not a multiple of device blocksize";
return -EINVAL;
}
--
--
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