Open read delegation and file locks implementation in the kernel 2.6.37-rc1 are not consistent with the RFC3530. In the kernel 2.6.37-rc1: 1.NFS client mount NFS filesytem with nfsv4. 2.The client open a NFS file with O_RDONLY,then the server may return a read delegation to the client. 3.for some reasons, the network between client and server is partition. 4.the client lock the opened file with F_RDLCK again.If the client has the read delegation at the step 2,it will return ture.In fact,the client doesn't send the read lock request to the NFS service.It does operate the request at local. But the RFC3530 descripts as: 9.4.2. Open Delegation and File Locks When a client holds a write open delegation, lock operations may be performed locally. This includes those required for mandatory file locking. This can be done since the delegation implies that there can be no conflicting locks. Similarly, all of the revalidations that would normally be associated with obtaining locks and the flushing of data associated with the releasing of locks need not be done. When a client holds a read open delegation, lock operations are not performed locally. All lock operations, including those requesting non-exclusive locks, are sent to the server for resolution. Is this a bug or the kernel have other considerations When it implements this function? -- 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
