Kernel 2.6.37 would most likely add a new mount option: local_lock. Document the new option in the nfs(5) man page. Signed-off-by: Suresh Jayaraman <sjayaraman@xxxxxxx> --- utils/mount/nfs.man | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 44 insertions(+), 0 deletions(-) diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man index 55d4b55..d2a4c5f 100644 --- a/utils/mount/nfs.man +++ b/utils/mount/nfs.man @@ -717,6 +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. -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
