PNFS Todo List

Revision as of 23:26, 28 February 2009 by Dhildebz (Talk | contribs)

NFSv4.1 (sessions) Todo List

[2009-02] mount version negotiation
- Propagate error up to the mount system call (Andy)
- Update mount utils command to reissue the mount with a different version (SteveD)
[2009-02] New backchannel implementation that handles multiple flavor authentication (Ricardo)
[2009-02] Documentation
- What functionality is supported? What will a user be able to do?
[2009-02] Lock Sequencing
- With the advent of Sessions, the open sequencing should be reworked to avoid double sequencing. No need to sequence in the operations if the session is already sequencing (Lower priority)
[2008-08] Propose design for unified client/LD device cache. (Benny)

Bug 172 - EXCHANGE_ID does not reply on first request (Andy)
[2009-02] Client should validate Backchannel attributes
- The client determines the resources used by the backchannel. If the server ignores the client specification, and changes the values, the client shou8ld drop the mount to v4
Bruce wants a patch for the Documentation directory that explains which features we have implemented and which we have not.
- He wants this done from a user's perspective - what would a fully functional NFSv4.1 sessions client see from the server?
- Document the ramifications of the present implementation
  - shortcuts we made.
  - Document server owner implementation.
[2008-10] Never return NFS4ERR_RESOURCE in nfs41/pnfs. Error code was deprecated. Typically need to return NFS4ERR_REQ_TOO_BIG instead.
[2008-04-10] Add an option to control nfsv4.1 on the server side.
- The motivation is disabling 4.1 on the server without having to rebuild the kernel. Some use cases: a faulty 4.1 client, or one that's crashing the server, or just for easier debugging of the client (4.1 client mounting a 4.0 server).

The following still need to be addressed:

[11/51] nfsd41-sessions-basic-data-types.patch we'll need at least one per-session max. variable maybe a global max.
- nfsd_compoundargs has a max size for the preallocated ops array. need to define that in a header file use for both nfs4 and nfs41. (preallocated per nfsd thread)
- review storing negotiated back channel session parameters
[23] nfsd41-xdr-stubs.patch
- review 11-13: add comment about why we don't need nfsd4_enc_ops per minorversion like we do for the decoding vector.
0030-nfsd41-destroy_session-operation.patch
- > + shutdown_callback_client(ses->se_client);
- review 11-12: we need ref. counting for that backchannel to support trunking.
- clp->cl_callback.cb_client is shared?
Write a commit message for [PATCH 36/46] nfsd41: sunrpc: Added rpc server-side backchannel handling
- FIXME: bhalevy: write up commit message
Need to discuss multiple per client session fore and back channel support.
Ensure the server passes all of the pynfs4.1 testserver.py tests.
- A bit of work here.
Ensure the server passes all of the pynfs4.0 testserver.py tests that the unpatched server pases over a v4.0 mount when CONFIG_NFSD_V4_1 is configured, and when it is not.
- A bit of work here.

[2009-02] Complete file layout server-to-server stateid distribution implementation. pNFS File-based Stateid Distribution Design

[2008-10] Properly define NFS4_DEV_NOTIFY_MAXENTRIES to handle anything that fits in the negotiated max. request size for the backchannel.

[2008-06-30] Separate pnfsd export and callback API out of export_operations. (Ricardo)

[2008-06-30] Clean up pnfsd callback vector registration model. Provide for orderly nfsd shutdown to allow the filesystem to recall layouts upon shutdown.

Identify new exported functions (Ricardo)
Identify updated data structures (Ricardo)
How shall the user specify to user pNFS for a mount?
- Today it's based on the previously loaded pNFS module
- Should this be a mount option? Should it always try pNFS if the server supports it?

[2008-08] Trond verbally NACKed rpc_call_validate_args, suggest looking into using existing rpc_call_prepare infrastructure instead. (Andy)

[2008-06-30] Change fs/nfsd/nfs4xdr.c decoding/encoding to table based (bhalevy)

[2008-04-07] Prepare and send nfs41 patches for review. (bhalevy)
- Depends on support for concurrent 4.0 and 4.1 mounts.

[2008-04-07] Add an option for nfsv4.1 to the nfs mount program.
- "{nfs,}vers=41" seems to be the most appropriate. See nfs_mount_option_tokens in fs/nfs/super.c. Note that kernel nfs root (in fs/nfs/nfsroot.c does not current (2.6.25-rc8) support root over nfsv4 only "nfsvers=[23]".

Agree on LD API changes for block layout (Fred and Dean) then merge generic pnfs patch (fred-pnfs) into pnfs branch. (bhalevy)