From c46556c6be057da79f51b1a8325ec4c27938bd49 Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Mon, 18 Jul 2011 18:40:21 -0400 Subject: nfsd4: update nfsv4.1 implementation notes Update documentation to reflect recent progress. Signed-off-by: J. Bruce Fields --- Documentation/filesystems/nfs/nfs41-server.txt | 33 ++++++++------------------ 1 file changed, 10 insertions(+), 23 deletions(-) (limited to 'Documentation/filesystems/nfs/nfs41-server.txt') diff --git a/Documentation/filesystems/nfs/nfs41-server.txt b/Documentation/filesystems/nfs/nfs41-server.txt index 04884914a1c8..092fad92a3f0 100644 --- a/Documentation/filesystems/nfs/nfs41-server.txt +++ b/Documentation/filesystems/nfs/nfs41-server.txt @@ -39,27 +39,17 @@ interoperability problems with future clients. Known issues: from a linux client are possible, but we aren't really conformant with the spec (for example, we don't use kerberos on the backchannel correctly). - - no trunking support: no clients currently take advantage of - trunking, but this is a mandatory feature, and its use is - recommended to clients in a number of places. (E.g. to ensure - timely renewal in case an existing connection's retry timeouts - have gotten too long; see section 8.3 of the RFC.) - Therefore, lack of this feature may cause future clients to - fail. - Incomplete backchannel support: incomplete backchannel gss support and no support for BACKCHANNEL_CTL mean that callbacks (hence delegations and layouts) may not be available and clients confused by the incomplete implementation may fail. - - Server reboot recovery is unsupported; if the server reboots, - clients may fail. - We do not support SSV, which provides security for shared client-server state (thus preventing unauthorized tampering with locks and opens, for example). It is mandatory for servers to support this, though no clients use it yet. - Mandatory operations which we do not support, such as - DESTROY_CLIENTID, FREE_STATEID, SECINFO_NO_NAME, and - TEST_STATEID, are not currently used by clients, but will be + DESTROY_CLIENTID, are not currently used by clients, but will be (and the spec recommends their uses in common cases), and clients should not be expected to know how to recover from the case where they are not supported. This will eventually cause @@ -69,8 +59,9 @@ In addition, some limitations are inherited from the current NFSv4 implementation: - Incomplete delegation enforcement: if a file is renamed or - unlinked, a client holding a delegation may continue to - indefinitely allow opens of the file under the old name. + unlinked by a local process, a client holding a delegation may + continue to indefinitely allow opens of the file under the old + name. The table below, taken from the NFSv4.1 document, lists the operations that are mandatory to implement (REQ), optional @@ -99,7 +90,7 @@ Operations +----------------------+------------+--------------+----------------+ | ACCESS | REQ | | Section 18.1 | NS | BACKCHANNEL_CTL | REQ | | Section 18.33 | -NS | BIND_CONN_TO_SESSION | REQ | | Section 18.34 | +I | BIND_CONN_TO_SESSION | REQ | | Section 18.34 | | CLOSE | REQ | | Section 18.2 | | COMMIT | REQ | | Section 18.3 | | CREATE | REQ | | Section 18.4 | @@ -111,7 +102,7 @@ NS*| DELEGPURGE | OPT | FDELG (REQ) | Section 18.5 | NS | DESTROY_CLIENTID | REQ | | Section 18.50 | I | DESTROY_SESSION | REQ | | Section 18.37 | I | EXCHANGE_ID | REQ | | Section 18.35 | -NS | FREE_STATEID | REQ | | Section 18.38 | +I | FREE_STATEID | REQ | | Section 18.38 | | GETATTR | REQ | | Section 18.7 | P | GETDEVICEINFO | OPT | pNFS (REQ) | Section 18.40 | P | GETDEVICELIST | OPT | pNFS (OPT) | Section 18.41 | @@ -145,14 +136,14 @@ NS*| OPENATTR | OPT | | Section 18.17 | | RESTOREFH | REQ | | Section 18.27 | | SAVEFH | REQ | | Section 18.28 | | SECINFO | REQ | | Section 18.29 | -NS | SECINFO_NO_NAME | REC | pNFS files | Section 18.45, | +I | SECINFO_NO_NAME | REC | pNFS files | Section 18.45, | | | | layout (REQ) | Section 13.12 | I | SEQUENCE | REQ | | Section 18.46 | | SETATTR | REQ | | Section 18.30 | | SETCLIENTID | MNI | | N/A | | SETCLIENTID_CONFIRM | MNI | | N/A | NS | SET_SSV | REQ | | Section 18.47 | -NS | TEST_STATEID | REQ | | Section 18.48 | +I | TEST_STATEID | REQ | | Section 18.48 | | VERIFY | REQ | | Section 18.31 | NS*| WANT_DELEGATION | OPT | FDELG (OPT) | Section 18.49 | | WRITE | REQ | | Section 18.32 | @@ -206,12 +197,6 @@ CREATE_SESSION: SEQUENCE: * no support for dynamic slot table renegotiation (optional) -nfsv4.1 COMPOUND rules: -The following cases aren't supported yet: -* Enforcing of NFS4ERR_NOT_ONLY_OP for: BIND_CONN_TO_SESSION, CREATE_SESSION, - DESTROY_CLIENTID, DESTROY_SESSION, EXCHANGE_ID. -* DESTROY_SESSION MUST be the final operation in the COMPOUND request. - Nonstandard compound limitations: * No support for a sessions fore channel RPC compound that requires both a ca_maxrequestsize request and a ca_maxresponsesize reply, so we may @@ -219,3 +204,5 @@ Nonstandard compound limitations: negotiation. * No more than one IO operation (read, write, readdir) allowed per compound. + +See also http://wiki.linux-nfs.org/wiki/index.php/Server_4.0_and_4.1_issues. -- cgit v1.2.1