osbase/fsquota: replace float calculation

Floats have limited precision and are not needed here.

Change-Id: I51053821af226d312e94d51c4d21224e1ca53908
Reviewed-on: https://review.monogon.dev/c/monogon/+/4009
Tested-by: Jenkins CI
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
diff --git a/osbase/fsquota/fsquota.go b/osbase/fsquota/fsquota.go
index 4919841..e4f3e92 100644
--- a/osbase/fsquota/fsquota.go
+++ b/osbase/fsquota/fsquota.go
@@ -11,7 +11,6 @@
 import (
 	"errors"
 	"fmt"
-	"math"
 	"os"
 
 	"golang.org/x/sys/unix"
@@ -84,7 +83,10 @@
 	}
 
 	// Always round up to the nearest block size
-	bytesLimitBlocks := uint64(math.Ceil(float64(maxBytes) / float64(1024)))
+	bytesLimitBlocks := maxBytes / 1024
+	if bytesLimitBlocks*1024 < maxBytes {
+		bytesLimitBlocks += 1
+	}
 
 	return quotactl.SetQuota(dir, quotactl.QuotaTypeProject, lastID, &quotactl.Quota{
 		BHardLimit: bytesLimitBlocks,