zfs mount man page should document legacy behaviour

Document legacy mount behavior.

Reviewed by: Allan Jude <allanjude@freebsd.org>
Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: bunder2015 <omfgbunder@gmail.com>
Reviewed-by: loli10K <ezomori.nozomu@gmail.com>
Signed-off-by: Kash Pande <kash@tripleback.net>
Closes #2900
Closes #8414

diff --git a/man/man8/zfs.8 b/man/man8/zfs.8
index 551089609fdb911ee225f58766417408b07f1f6a..c4c172155ae2c36fe47052c8daab8699210c9115 100644 (file)
--- a/man/man8/zfs.8
+++ b/man/man8/zfs.8
@@ -3304,16 +3304,24 @@ Displays all ZFS file systems currently mounted.
 .Op Fl o Ar options
 .Fl a | Ar filesystem
 .Xc
-Mounts ZFS file systems.
+Mount ZFS filesystem on a path described by its
+.Sy mountpoint
+property, if the path exists and is empty. If
+.Sy mountpoint
+is set to
+.Em legacy ,
+the filesystem should be instead mounted using
+.Xr mount 8 .
 .Bl -tag -width "-O"
 .It Fl O
-Perform an overlay mount.
+Perform an overlay mount. Allows mounting in non-empty
+.Sy mountpoint .
 See
 .Xr mount 8
 for more information.
 .It Fl a
 Mount all available ZFS file systems.
-Invoked automatically as part of the boot process.
+Invoked automatically as part of the boot process if configured.
 .It Ar filesystem
 Mount the specified filesystem.
 .It Fl o Ar options