nfsd41: use sv_max_mesg for forechannel max sizes (ddc04fd4) · Commits · 戴 / test

ca_maxresponsesize and ca_maxrequest size include the RPC header. sv_max_mesg is sv_max_payolad plus a page for overhead and is used in svc_init_buffer to allocate server buffer space for both the request and reply. Note that this means we can service an RPC compound that requires ca_maxrequestsize (MAXWRITE) or ca_max_responsesize (MAXREAD) but that we do not support an RPC compound that requires both ca_maxrequestsize and ca_maxresponsesize. Signed-off-by:

Andy Adamson <andros@netapp.com> [bfields@citi.umich.edu: more documentation updates] Signed-off-by:

J. Bruce Fields <bfields@citi.umich.edu>

Documentation/filesystems/nfs41-server.txt

+7 −0

Original line number	Diff line number	Diff line
		@@ -213,3 +213,10 @@ The following cases aren't supported yet:
		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
		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.

fs/nfsd/nfs4state.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -477,13 +477,14 @@ static int set_forechannel_drc_size(struct nfsd4_channel_attrs *fchan)

		/*
		* fchan holds the client values on input, and the server values on output
		* sv_max_mesg is the maximum payload plus one page for overhead.
		*/
		static int init_forechannel_attrs(struct svc_rqst *rqstp,
		struct nfsd4_channel_attrs *session_fchan,
		struct nfsd4_channel_attrs *fchan)
		{
		int status = 0;
		__u32 maxcount = svc_max_payload(rqstp);
		__u32 maxcount = nfsd_serv->sv_max_mesg;

		/* headerpadsz set to zero in encode routine */

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