4a4e3b7632
The NFSv4 RFCs give a server the option of allowing the use of an open stateid for write access to be used for a Read operation. This patch enables this by default and adds a sysctl to disable it, for anyone who does not want this capability. Allowing this is particularily useful for a pNFS Data Server (DS), since they are not permitted to allow the use of special stateids. Discovered during recent testing of the pNFS server under development. MFC after: 2 weeks