nfsd41: split out share_access want and signal flags while decoding

Signed-off-by: Benny Halevy <bhalevy@tonian.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

fs/nfsd/nfs4proc.c

@@ -311,9 +311,6 @@ nfsd4_open(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 	if (open->op_create && open->op_claim_type != NFS4_OPEN_CLAIM_NULL)
 		return nfserr_inval;
 
-	/* We don't yet support WANT bits: */
-	open->op_share_access &= NFS4_SHARE_ACCESS_MASK;
-
 	open->op_created = 0;
 	/*
 	 * RFC5661 18.51.3

fs/nfsd/nfs4state.c

@@ -2637,8 +2637,6 @@ nfs4_check_delegmode(struct nfs4_delegation *dp, int flags)
 
 static int share_access_to_flags(u32 share_access)
 {
-	share_access &= NFS4_SHARE_ACCESS_MASK;
-
 	return share_access == NFS4_SHARE_ACCESS_READ ? RD_STATE : WR_STATE;
 }
 
@@ -3600,7 +3598,9 @@ nfsd4_open_downgrade(struct svc_rqst *rqstp,
 			cstate->current_fh.fh_dentry->d_name.name);
 
 	/* We don't yet support WANT bits: */
-	od->od_share_access &= NFS4_SHARE_ACCESS_MASK;
+	if (od->od_deleg_want)
+		dprintk("NFSD: %s: od_deleg_want=0x%x ignored\n", __func__,
+			od->od_deleg_want);
 
 	nfs4_lock_state();
 	status = nfs4_preprocess_confirmed_seqid_op(cstate, od->od_seqid,

fs/nfsd/nfs4xdr.c

@@ -638,14 +638,18 @@ nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup
 	DECODE_TAIL;
 }
 
-static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *x)
+static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
 {
 	__be32 *p;
 	u32 w;
 
 	READ_BUF(4);
 	READ32(w);
-	*x = w;
+	*share_access = w & NFS4_SHARE_ACCESS_MASK;
+	*deleg_want = w & NFS4_SHARE_WANT_MASK;
+	if (deleg_when)
+		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
+
 	switch (w & NFS4_SHARE_ACCESS_MASK) {
 	case NFS4_SHARE_ACCESS_READ:
 	case NFS4_SHARE_ACCESS_WRITE:
@@ -673,6 +677,9 @@ static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *x)
 	w &= ~NFS4_SHARE_WANT_MASK;
 	if (!w)
 		return nfs_ok;
+
+	if (!deleg_when)	/* open_downgrade */
+		return nfserr_inval;
 	switch (w) {
 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
@@ -719,6 +726,7 @@ static __be32
 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
 {
 	DECODE_HEAD;
+	u32 dummy;
 
 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
 	open->op_iattr.ia_valid = 0;
@@ -727,7 +735,9 @@ nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
 	/* seqid, share_access, share_deny, clientid, ownerlen */
 	READ_BUF(4);
 	READ32(open->op_seqid);
-	status = nfsd4_decode_share_access(argp, &open->op_share_access);
+	/* decode, yet ignore deleg_when until supported */
+	status = nfsd4_decode_share_access(argp, &open->op_share_access,
+					   &open->op_deleg_want, &dummy);
 	if (status)
 		goto xdr_error;
 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
@@ -848,7 +858,8 @@ nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_d
 		return status;
 	READ_BUF(4);
 	READ32(open_down->od_seqid);
-	status = nfsd4_decode_share_access(argp, &open_down->od_share_access);
+	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
+					   &open_down->od_deleg_want, NULL);
 	if (status)
 		return status;
 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);

fs/nfsd/xdr4.h

@@ -233,6 +233,7 @@ struct nfsd4_open {
 	u32		op_seqid;           /* request */
 	u32		op_share_access;    /* request */
 	u32		op_share_deny;      /* request */
+	u32		op_deleg_want;      /* request */
 	stateid_t	op_stateid;         /* response */
 	u32		op_recall;          /* recall */
 	struct nfsd4_change_info  op_cinfo; /* response */
@@ -256,8 +257,9 @@ struct nfsd4_open_confirm {
 struct nfsd4_open_downgrade {
 	stateid_t       od_stateid;
 	u32             od_seqid;
-	u32             od_share_access;
-	u32             od_share_deny;
+	u32             od_share_access;	/* request */
+	u32		od_deleg_want;		/* request */
+	u32             od_share_deny;		/* request */
 };