NFSv4: Add recovery of attribute delegations

After a reboot of the NFSv4.2 server, the recovery code needs to specify
whether the delegation to be recovered is an attribute delegation or
not.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

fs/nfs/nfs4proc.c

@@ -2225,7 +2225,7 @@ static int _nfs4_do_open_reclaim(struct nfs_open_context *ctx, struct nfs4_state
 {
 	struct nfs_delegation *delegation;
 	struct nfs4_opendata *opendata;
-	fmode_t delegation_type = 0;
+	u32 delegation_type = NFS4_OPEN_DELEGATE_NONE;
 	int status;
 
 	opendata = nfs4_open_recoverdata_alloc(ctx, state,
@@ -2234,8 +2234,20 @@ static int _nfs4_do_open_reclaim(struct nfs_open_context *ctx, struct nfs4_state
 		return PTR_ERR(opendata);
 	rcu_read_lock();
 	delegation = rcu_dereference(NFS_I(state->inode)->delegation);
-	if (delegation != NULL && test_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags) != 0)
-		delegation_type = delegation->type;
+	if (delegation != NULL && test_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags) != 0) {
+		switch(delegation->type) {
+		case FMODE_READ:
+			delegation_type = NFS4_OPEN_DELEGATE_READ;
+			if (test_bit(NFS_DELEGATION_DELEGTIME, &delegation->flags))
+				delegation_type = NFS4_OPEN_DELEGATE_READ_ATTRS_DELEG;
+			break;
+		case FMODE_WRITE:
+		case FMODE_READ|FMODE_WRITE:
+			delegation_type = NFS4_OPEN_DELEGATE_WRITE;
+			if (test_bit(NFS_DELEGATION_DELEGTIME, &delegation->flags))
+				delegation_type = NFS4_OPEN_DELEGATE_WRITE_ATTRS_DELEG;
+		}
+	}
 	rcu_read_unlock();
 	opendata->o_arg.u.delegation_type = delegation_type;
 	status = nfs4_open_recover(opendata, state);

fs/nfs/nfs4xdr.c

@@ -1475,20 +1475,18 @@ static void encode_opentype(struct xdr_stream *xdr, const struct nfs_openargs *a
 	}
 }
 
-static inline void encode_delegation_type(struct xdr_stream *xdr, fmode_t delegation_type)
+static inline void encode_delegation_type(struct xdr_stream *xdr, u32 delegation_type)
 {
 	__be32 *p;
 
 	p = reserve_space(xdr, 4);
 	switch (delegation_type) {
-	case 0:
-		*p = cpu_to_be32(NFS4_OPEN_DELEGATE_NONE);
-		break;
-	case FMODE_READ:
-		*p = cpu_to_be32(NFS4_OPEN_DELEGATE_READ);
-		break;
-	case FMODE_WRITE|FMODE_READ:
-		*p = cpu_to_be32(NFS4_OPEN_DELEGATE_WRITE);
+	case NFS4_OPEN_DELEGATE_NONE:
+	case NFS4_OPEN_DELEGATE_READ:
+	case NFS4_OPEN_DELEGATE_WRITE:
+	case NFS4_OPEN_DELEGATE_READ_ATTRS_DELEG:
+	case NFS4_OPEN_DELEGATE_WRITE_ATTRS_DELEG:
+		*p = cpu_to_be32(delegation_type);
 		break;
 	default:
 		BUG();
@@ -1504,7 +1502,7 @@ static inline void encode_claim_null(struct xdr_stream *xdr, const struct qstr *
 	encode_string(xdr, name->len, name->name);
 }
 
-static inline void encode_claim_previous(struct xdr_stream *xdr, fmode_t type)
+static inline void encode_claim_previous(struct xdr_stream *xdr, u32 type)
 {
 	__be32 *p;
 

include/linux/nfs_xdr.h

@@ -484,7 +484,7 @@ struct nfs_openargs {
 			nfs4_verifier   verifier; /* EXCLUSIVE */
 		};
 		nfs4_stateid	delegation;		/* CLAIM_DELEGATE_CUR */
-		fmode_t		delegation_type;	/* CLAIM_PREVIOUS */
+		__u32		delegation_type;	/* CLAIM_PREVIOUS */
 	} u;
 	const struct qstr *	name;
 	const struct nfs_server *server;	 /* Needed for ID mapping */