The kernel 2.6.37 has a add new mount option: local_lock.

[nfs-utils.git] / utils / mount / nfs.man

diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man
index fe58015d04f14c7402bf194de5040ee5219a0d2e..d2a4c5f574130fcc0891e2f63e195c3b76b54738 100644 (file)
--- a/utils/mount/nfs.man
+++ b/utils/mount/nfs.man
@@ -481,7 +481,10 @@ command,
 .I netid
 is a valid netid listed in
 .IR /etc/netconfig .
-Otherwise,
+The value "rdma" may also be specified.
+If the
+.B mount.nfs
+command does not have TI-RPC support, then
 .I netid
 is one of "tcp," "udp," or "rdma," and only IPv4 may be used.
 .IP
@@ -523,6 +526,12 @@ option is an alternative to specifying
 .BR proto=tcp.
 It is included for compatibility with other operating systems.
 .TP 1.5i
+.B rdma
+The
+.B rdma
+option is an alternative to specifying
+.BR proto=rdma.
+.TP 1.5i
 .BI port= n
 The numeric value of the server's NFS service port.
 If the server's NFS service is not available on the specified port,
@@ -708,6 +717,50 @@ If this option is not specified, the NFS client uses READDIRPLUS requests
 on NFS version 3 mounts to read small directories.
 Some applications perform better if the client uses only READDIR requests
 for all directories.
+.TP 1.5i
+.BR local_lock= mechanism
+Specifies whether to use local locking for any or both of the flock and the
+POSIX locking mechanisms.
+.I mechanism
+can be one of
+.BR all ,
+.BR flock ,
+.BR posix ,
+or
+.BR none .
+This option is supported in kernels 2.6.37 and later.
+.IP
+The Linux NFS client provides a way to make locks local. This means, the
+applications can lock files, but such locks provide exclusion only against
+other applications running on the same client. Remote applications are not
+affected by these locks.
+.IP
+If this option is not specified, or if
+.B none
+is specified, the client assumes that the locks are not local.
+.IP
+If
+.BR all
+is specified, the client assumes that both flock and POSIX locks are local.
+.IP
+If
+.BR flock
+is specified, the client assumes that only flock locks are local and uses
+NLM sideband protocol to lock files when POSIX locks are used.
+.IP
+If
+.BR posix
+is specified, the client assumes that POSIX locks are local and uses NLM
+sideband protocol to lock files when flock locks are used.
+.IP
+To support legacy flock behavior similar to that of NFS clients < 2.6.12, use
+'local_lock=flock'. This option is required when exporting NFS mounts via
+Samba as Samba maps Windows share mode locks as flock. Since NFS clients >
+2.6.12 implement flock by emulating POSIX locks, this will result in
+conflicting locks.
+.IP
+NOTE: When used together, the 'local_lock' mount option will be overridden
+by 'nolock'/'lock' mount option.
 .SS "Options for version 4 only"
 Use these options, along with the options in the first subsection above,
 for NFSv4 only. They will be ignored with older versions.