Commit 9b3234b9 authored Dec 04, 2012 by J. Bruce Fields

nfsd4: disable zero-copy on non-final read ops

To ensure ordering of read data with any following operations, turn off
zero copy if the read is not the final operation in the compound.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

parent 3a28e331

fs/nfsd/nfs4proc.c

+11 −0

Original line number	Diff line number	Diff line
		@@ -692,6 +692,17 @@ nfsd4_read(struct svc_rqst rqstp, struct nfsd4_compound_state cstate,
		if (read->rd_offset >= OFFSET_MAX)
		return nfserr_inval;

		/*
		* If we do a zero copy read, then a client will see read data
		* that reflects the state of the file after performing the
		* following compound.
		*
		* To ensure proper ordering, we therefore turn off zero copy if
		* the client wants us to do more in this compound:
		*/
		if (!nfsd4_last_compound_op(rqstp))
		rqstp->rq_splice_ok = false;

		nfs4_lock_state();
		/* check stateid */
		if ((status = nfs4_preprocess_stateid_op(SVC_NET(rqstp),

fs/nfsd/nfs4state.c

+0 −8

Original line number	Diff line number	Diff line
		@@ -1855,14 +1855,6 @@ out_free_session:
		goto out;
		}

		static bool nfsd4_last_compound_op(struct svc_rqst *rqstp)
		{
		struct nfsd4_compoundres *resp = rqstp->rq_resp;
		struct nfsd4_compoundargs *argp = rqstp->rq_argp;

		return argp->opcnt == resp->opcnt;
		}

		static __be32 nfsd4_map_bcts_dir(u32 *dir)
		{
		switch (*dir) {

fs/nfsd/xdr4.h

+8 −0

Original line number	Diff line number	Diff line
		@@ -528,6 +528,14 @@ static inline bool nfsd4_not_cached(struct nfsd4_compoundres *resp)
		\|\| nfsd4_is_solo_sequence(resp);
		}

		static inline bool nfsd4_last_compound_op(struct svc_rqst *rqstp)
		{
		struct nfsd4_compoundres *resp = rqstp->rq_resp;
		struct nfsd4_compoundargs *argp = rqstp->rq_argp;

		return argp->opcnt == resp->opcnt;
		}

		#define NFS4_SVC_XDRSIZE sizeof(struct nfsd4_compoundargs)

		static inline void