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>

@@ -503,10 +503,15 @@
         { VOPNAME_PATHCONF,     { .vop_pathconf = zfsctl_pathconf }     },
         { VOPNAME_FID,          { .vop_fid = zfsctl_common_fid  }       },
         { NULL }
 };
 
+/*
+ * Gets the full dataset name that corresponds to the given snapshot name
+ * Example:
+ *      zfsctl_snapshot_zname("snap1") -> "mypool/myfs@snap1"
+ */
 static int
 zfsctl_snapshot_zname(vnode_t *vp, const char *name, int len, char *zname)
 {
         objset_t *os = ((zfsvfs_t *)((vp)->v_vfsp->vfs_data))->z_os;