From cb73a9f4649bf63c0397e565a15abf8a91ecf56f Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Thu, 1 Nov 2012 18:09:48 -0400 Subject: nfsd4: implement backchannel_ctl operation This operation is mandatory for servers to implement. Signed-off-by: J. Bruce Fields --- Documentation/filesystems/nfs/nfs41-server.txt | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/nfs/nfs41-server.txt b/Documentation/filesystems/nfs/nfs41-server.txt index 092fad92a3f0..f5ddff2da302 100644 --- a/Documentation/filesystems/nfs/nfs41-server.txt +++ b/Documentation/filesystems/nfs/nfs41-server.txt @@ -39,11 +39,6 @@ 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). - - 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. - 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 @@ -89,7 +84,7 @@ Operations | | MNI | or OPT) | | +----------------------+------------+--------------+----------------+ | ACCESS | REQ | | Section 18.1 | -NS | BACKCHANNEL_CTL | REQ | | Section 18.33 | +I | BACKCHANNEL_CTL | REQ | | Section 18.33 | I | BIND_CONN_TO_SESSION | REQ | | Section 18.34 | | CLOSE | REQ | | Section 18.2 | | COMMIT | REQ | | Section 18.3 | -- cgit From 292a41716a4ad3e93c57155f99786abe8a8d386a Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Wed, 7 Nov 2012 19:41:51 -0500 Subject: nfsd4: update documentation on 4.1 progress Signed-off-by: J. Bruce Fields --- Documentation/filesystems/nfs/nfs41-server.txt | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/nfs/nfs41-server.txt b/Documentation/filesystems/nfs/nfs41-server.txt index f5ddff2da302..392ef637e101 100644 --- a/Documentation/filesystems/nfs/nfs41-server.txt +++ b/Documentation/filesystems/nfs/nfs41-server.txt @@ -43,12 +43,6 @@ interoperability problems with future clients. Known issues: 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, 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 - interoperability failures. In addition, some limitations are inherited from the current NFSv4 implementation: @@ -94,7 +88,7 @@ NS*| DELEGPURGE | OPT | FDELG (REQ) | Section 18.5 | | DELEGRETURN | OPT | FDELG, | Section 18.6 | | | | DDELG, pNFS | | | | | (REQ) | | -NS | DESTROY_CLIENTID | REQ | | Section 18.50 | +I | DESTROY_CLIENTID | REQ | | Section 18.50 | I | DESTROY_SESSION | REQ | | Section 18.37 | I | EXCHANGE_ID | REQ | | Section 18.35 | I | FREE_STATEID | REQ | | Section 18.38 | @@ -187,7 +181,6 @@ EXCHANGE_ID: CREATE_SESSION: * backchannel attributes are ignored -* backchannel security parameters are ignored SEQUENCE: * no support for dynamic slot table renegotiation (optional) -- cgit From ffe1137ba743cdf1c2414d5a89690aec1daa6bba Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Thu, 15 Nov 2012 14:52:19 -0500 Subject: nfsd4: delay filling in write iovec array till after xdr decoding Our server rejects compounds containing more than one write operation. It's unclear whether this is really permitted by the spec; with 4.0, it's possibly OK, with 4.1 (which has clearer limits on compound parameters), it's probably not OK. No client that we're aware of has ever done this, but in theory it could be useful. The source of the limitation: we need an array of iovecs to pass to the write operation. In the worst case that array of iovecs could have hundreds of elements (the maximum rwsize divided by the page size), so it's too big to put on the stack, or in each compound op. So we instead keep a single such array in the compound argument. We fill in that array at the time we decode the xdr operation. But we decode every op in the compound before executing any of them. So once we've used that array we can't decode another write. If we instead delay filling in that array till the time we actually perform the write, we can reuse it. Another option might be to switch to decoding compound ops one at a time. I considered doing that, but it has a number of other side effects, and I'd rather fix just this one problem for now. Signed-off-by: J. Bruce Fields --- Documentation/filesystems/nfs/nfs41-server.txt | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/nfs/nfs41-server.txt b/Documentation/filesystems/nfs/nfs41-server.txt index 392ef637e101..01c2db769791 100644 --- a/Documentation/filesystems/nfs/nfs41-server.txt +++ b/Documentation/filesystems/nfs/nfs41-server.txt @@ -190,7 +190,7 @@ Nonstandard compound limitations: ca_maxrequestsize request and a ca_maxresponsesize reply, so we may fail to live up to the promise we made in CREATE_SESSION fore channel negotiation. -* No more than one IO operation (read, write, readdir) allowed per - compound. +* No more than one read-like operation allowed per compound; encoding + replies that cross page boundaries (except for read data) not handled. See also http://wiki.linux-nfs.org/wiki/index.php/Server_4.0_and_4.1_issues. -- cgit