Commit b85d4c01 authored by Benny Halevy's avatar Benny Halevy Committed by J. Bruce Fields
Browse files

nfsd41: sequence operation 

Implement the sequence operation conforming to
http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-26



Check for stale clientid (as derived from the sessionid).
Enforce slotid range and exactly-once semantics using
the slotid and seqid.

If everything went well renew the client lease and
mark the slot INPROGRESS.

Add a struct nfsd4_slot pointer to struct nfsd4_compound_state.
To be used for sessions DRC replay.

[nfsd41: rename sequence catchthis to cachethis]
Signed-off-by: default avatarAndy <Adamson&lt;andros@netapp.com>
[pulled some code to set cstate->slot from "nfsd DRC logic"]
[use sessionid_lock spin lock]
[nfsd41: use bool inuse for slot state]
Signed-off-by: default avatarBenny Halevy <bhalevy@panasas.com>
[nfsd: add a struct nfsd4_slot pointer to struct nfsd4_compound_state]
Signed-off-by: default avatarAndy Adamson <andros@netapp.com>
Signed-off-by: default avatarBenny Halevy <bhalevy@panasas.com>
[nfsd41: add nfsd4_session pointer to nfsd4_compound_state]
[nfsd41: set cstate session]
[nfsd41: use cstate session in nfsd4_sequence]
Signed-off-by: default avatarAndy Adamson <andros@netapp.com>
Signed-off-by: default avatarBenny Halevy <bhalevy@panasas.com>
[simplify nfsd4_encode_sequence error handling]
Signed-off-by: default avatarBenny Halevy <bhalevy@panasas.com>
Signed-off-by: default avatarJ. Bruce Fields <bfields@citi.umich.edu>
parent a1bcecd2

fs/nfsd/nfs4state.c

+71 −2
Original line number Diff line number Diff line
@@ -1000,6 +1000,32 @@ error: 
	return status;

}



static int

check_slot_seqid(u32 seqid, struct nfsd4_slot *slot)

{

	dprintk("%s enter. seqid %d slot->sl_seqid %d\n", __func__, seqid,

		slot->sl_seqid);



	/* The slot is in use, and no response has been sent. */

	if (slot->sl_inuse) {

		if (seqid == slot->sl_seqid)

			return nfserr_jukebox;

		else

			return nfserr_seq_misordered;

	}

	/* Normal */

	if (likely(seqid == slot->sl_seqid + 1))

		return nfs_ok;

	/* Replay */

	if (seqid == slot->sl_seqid)

		return nfserr_replay_cache;

	/* Wraparound */

	if (seqid == 1 && (slot->sl_seqid + 1) == 0)

		return nfs_ok;

	/* Misordered replay or misordered new request */

	return nfserr_seq_misordered;

}



__be32

nfsd4_create_session(struct svc_rqst *rqstp,

		     struct nfsd4_compound_state *cstate,
@@ -1017,11 +1043,54 @@ nfsd4_destroy_session(struct svc_rqst *r, 
}



__be32

nfsd4_sequence(struct svc_rqst *r,

nfsd4_sequence(struct svc_rqst *rqstp,

	       struct nfsd4_compound_state *cstate,

	       struct nfsd4_sequence *seq)

{

	return -1;	/* stub */

	struct nfsd4_session *session;

	struct nfsd4_slot *slot;

	int status;



	spin_lock(&sessionid_lock);

	status = nfserr_badsession;

	session = find_in_sessionid_hashtbl(&seq->sessionid);

	if (!session)

		goto out;



	status = nfserr_badslot;

	if (seq->slotid >= session->se_fnumslots)

		goto out;



	slot = &session->se_slots[seq->slotid];

	dprintk("%s: slotid %d\n", __func__, seq->slotid);



	status = check_slot_seqid(seq->seqid, slot);

	if (status == nfserr_replay_cache) {

		cstate->slot = slot;

		cstate->session = session;

		goto replay_cache;

	}

	if (status)

		goto out;



	/* Success! bump slot seqid */

	slot->sl_inuse = true;

	slot->sl_seqid = seq->seqid;



	cstate->slot = slot;

	cstate->session = session;



replay_cache:

	/* Renew the clientid on success and on replay.

	 * Hold a session reference until done processing the compound:

	 * nfsd4_put_session called only if the cstate slot is set.

	 */

	renew_client(session->se_client);

	nfsd4_get_session(session);

out:

	spin_unlock(&sessionid_lock);

	dprintk("%s: return %d\n", __func__, ntohl(status));

	return status;

}



__be32

fs/nfsd/nfs4xdr.c

+30 −3
Original line number Diff line number Diff line
@@ -1113,7 +1113,16 @@ static __be32 
nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,

		      struct nfsd4_sequence *seq)

{

	return nfserr_opnotsupp;	/* stub */

	DECODE_HEAD;



	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);

	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);

	READ32(seq->seqid);

	READ32(seq->slotid);

	READ32(seq->maxslots);

	READ32(seq->cachethis);



	DECODE_TAIL;

}



static __be32
@@ -2828,8 +2837,26 @@ static __be32 
nfsd4_encode_sequence(struct nfsd4_compoundres *resp, int nfserr,

		      struct nfsd4_sequence *seq)

{

	/* stub */

	ENCODE_HEAD;



	if (nfserr)

		return nfserr;



	RESERVE_SPACE(NFS4_MAX_SESSIONID_LEN + 20);

	WRITEMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);

	WRITE32(seq->seqid);

	WRITE32(seq->slotid);

	WRITE32(seq->maxslots);

	/*

	 * FIXME: for now:

	 *   target_maxslots = maxslots

	 *   status_flags = 0

	 */

	WRITE32(seq->maxslots);

	WRITE32(0);



	ADJUST_ARGS();

	return 0;

}



static __be32

include/linux/nfsd/xdr4.h

+12 −1
Original line number Diff line number Diff line
@@ -48,6 +48,9 @@ struct nfsd4_compound_state { 
	struct svc_fh		current_fh;

	struct svc_fh		save_fh;

	struct nfs4_stateowner	*replay_owner;

	/* For sessions DRC */

	struct nfsd4_session	*session;

	struct nfsd4_slot	*slot;

};



struct nfsd4_change_info {
@@ -358,7 +361,15 @@ struct nfsd4_create_session { 
};



struct nfsd4_sequence {

	int	foo;	/* stub */

	struct nfs4_sessionid	sessionid;		/* request/response */

	u32			seqid;			/* request/response */

	u32			slotid;			/* request/response */

	u32			maxslots;		/* request/response */

	u32			cachethis;		/* request */

#if 0

	u32			target_maxslots;	/* response */

	u32			status_flags;		/* response */

#endif /* not yet */

};



struct nfsd4_destroy_session {

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