I hope to get basic NFSv4 migration support into 3.12. This is the patch series, still based on 3.10, posted here for review. See also http://git.linux-nfs.org/?p=cel/cel-2.6.git;a=commit; h=8aa9aa847fdd073abe24789c5acb28b853755616 - Patch roadmap - The first two patches are bug fixes. Patches "NFS: Refactor nfs4_call_data_sequence()" through "NFS: Implement a transport blocking scheme for migration" introduce a mechanism that can plug and uncork an NFS transport. NFSv4.0 migration uses this mechanism to block forward NFS operations while migration recovery is occurring. NFSv4.1 and following will use session draining to accomplish the same. Patch "NFS: Add functions to swap transports during migration recovery" moves an nfs_server from one nfs_client to another, and swaps out the nfs_server's RPC transport at the same time. This mechanism probably still needs some work. Patches "NFS: Add method to retrieve fs_locations during migration recovery" through "NFS: Add migration recovery callouts in nfs4proc.c" add the bulk of support for recovering from NFS4ERR_MOVED. Patches "NFS: Add method to detect whether an FSID is still on the server" through "NFS: Implement support for NFS4ERR_LEASE_MOVED" add support for recovering from NFS4ERR_LEASE_MOVED. Patch "NFS: Set EXCHGID4_FLAG_SUPP_MOVED_MIGR" advertises migration support for NFSv4.1. - Merge criteria - I have three criteria for determining whether I believe this work is ready to merge: 1. The series doesn't regress any non-migration related functionality 2. Everyone is happy with the architecture and APIs, such that subsequent patches will amount to bug fixes and enhancements rather than reworking anything 3. The series is ported to the tip of Linus' master (3.11-rc1 as of this writing) I'd like to merge sooner rather than later so others can start to build on this functionality, and so I don't have to keep forward porting for another two years. In addition, this is something that distributions want yesterday. Including it now and then fixing it makes it easier for them to include it in their kernels. I expect bug fixes and enhancements after merge. Enhancements might include: Optimize LEASE_MOVED recovery by performing the fsid_present checks asynchronously Introduce support for fs_locations_info Finish NFSv4.1 migration support One thing that hasn't been tested yet is NFSv4.1 migration. There are no server implementations yet, and we believe there may be some (IETF) protocol work to do to get NFSv4.1 migration working reliably. We could drop that patch, or we could change it to add a CONFIG option, default N, marked EXPERIMENTAL so that the flag can be enabled conveniently for testing. - Test plan - This implementation still needs a lot of testing. I've done some of this list, plan to do more. * Single filesystem migration with TSM * Single filesystem migration without TSM * Active filesystem A while B is migrated (lease-moved recovery) * Active filesystem A while active filesystem B is migrated * Migrate filesystem A, reboot destination server, migrate B * Migration during lock-intensive workload * What happens when migration recovery fails? * How about migration with a Kerberos 5 mount? --- Chuck Lever (18): NFS: Never use user credentials for lease renewal NFS: Fix return type of nfs4_end_drain_session() stub NFS: Introduce a vector of migration recovery ops NFS: Refactor nfs4_call_data_sequence() NFS: Rename nfs41_call_sync_data as a common data structure NFS: Clean up nfs4_setup_sequence() NFS: Fix compiler warning in nfs_setup_sequence() NFS: Use RPC callouts to start NFSv4.0 synchronous requests NFS: Add a "struct nfs_server *" argument to nfs4_sequence_done() NFS: Implement a transport blocking scheme for migration NFS: Add a super_block backpointer to the nfs_server struct NFS: Add functions to swap transports during migration recovery NFS: Add method to retrieve fs_locations during migration recovery NFS: Add basic migration support to state manager thread NFS: Add migration recovery callouts in nfs4proc.c NFS: Add method to detect whether an FSID is still on the server NFS: Implement support for NFS4ERR_LEASE_MOVED NFS: Set EXCHGID4_FLAG_SUPP_MOVED_MIGR Trond Myklebust (1): SUNRPC: Add a helper to switch the transport of an rpc_clnt fs/nfs/client.c | 3 fs/nfs/internal.h | 3 fs/nfs/nfs4_fs.h | 36 +-- fs/nfs/nfs4client.c | 83 ++++++ fs/nfs/nfs4namespace.c | 114 +++++++++ fs/nfs/nfs4proc.c | 554 +++++++++++++++++++++++++++++++++++++------ fs/nfs/nfs4session.c | 2 fs/nfs/nfs4state.c | 318 +++++++++++++++++++++---- fs/nfs/nfs4xdr.c | 115 ++++++++- fs/nfs/super.c | 1 include/linux/nfs4.h | 1 include/linux/nfs_fs_sb.h | 11 + include/linux/nfs_xdr.h | 17 + include/linux/sunrpc/clnt.h | 4 net/sunrpc/clnt.c | 83 ++++++ 15 files changed, 1183 insertions(+), 162 deletions(-) -- Chuck Lever -- 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
