3741 zfs needs better comments
Submitted by:   Will Andrews <willa@spectralogic.com>
Submitted by:   Justin Gibbs <justing@spectralogic.com>
Submitted by:   Alan Somers <alans@spectralogic.com>
Reviewed by:    Matthew Ahrens <mahrens@delphix.com>

@@ -4426,10 +4426,15 @@
         }
 
         return (err);
 }
 
+/*
+ * Convert the zvol's volume size to an appropriate reservation.
+ * Note: If this routine is updated, it is necessary to update the ZFS test
+ * suite's shell version in reservation.kshlib.
+ */
 uint64_t
 zvol_volsize_to_reservation(uint64_t volsize, nvlist_t *props)
 {
         uint64_t numdb;
         uint64_t nblocks, volblocksize;