[RFC PATCH 1/4] NFS: Implement NFSv4.2's OFFLOAD_STATUS XDR

[cel@kernel.org]

From: Chuck Lever <chuck.lever@oracle.com>

Add XDR encoding and decoding functions for NFSv4.2 OFFLOAD_STATUS
operation.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfs/nfs42xdr.c       | 101 +++++++++++++++++++++++++++++++++++++++-
 fs/nfs/nfs4xdr.c        |   1 +
 include/linux/nfs4.h    |   1 +
 include/linux/nfs_xdr.h |   1 +
 4 files changed, 103 insertions(+), 1 deletion(-)

diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c
index 9e3ae53e2205..bafa0005d038 100644
--- a/fs/nfs/nfs42xdr.c
+++ b/fs/nfs/nfs42xdr.c
@@ -35,6 +35,11 @@
 #define encode_offload_cancel_maxsz	(op_encode_hdr_maxsz + \
 					 XDR_QUADLEN(NFS4_STATEID_SIZE))
 #define decode_offload_cancel_maxsz	(op_decode_hdr_maxsz)
+#define encode_offload_status_maxsz	(op_encode_hdr_maxsz + \
+					 XDR_QUADLEN(NFS4_STATEID_SIZE))
+#define decode_offload_status_maxsz	(op_decode_hdr_maxsz + \
+					 2 /* osr_count */ + \
+					 2 /* osr_complete */)
 #define encode_copy_notify_maxsz	(op_encode_hdr_maxsz + \
 					 XDR_QUADLEN(NFS4_STATEID_SIZE) + \
 					 1 + /* nl4_type */ \
@@ -143,6 +148,14 @@
 					 decode_sequence_maxsz + \
 					 decode_putfh_maxsz + \
 					 decode_offload_cancel_maxsz)
+#define NFS4_enc_offload_status_sz	(compound_encode_hdr_maxsz + \
+					 encode_sequence_maxsz + \
+					 encode_putfh_maxsz + \
+					 encode_offload_status_maxsz)
+#define NFS4_dec_offload_status_sz	(compound_decode_hdr_maxsz + \
+					 decode_sequence_maxsz + \
+					 decode_putfh_maxsz + \
+					 decode_offload_status_maxsz)
 #define NFS4_enc_copy_notify_sz		(compound_encode_hdr_maxsz + \
 					 encode_putfh_maxsz + \
 					 encode_copy_notify_maxsz)
@@ -343,6 +356,14 @@ static void encode_offload_cancel(struct xdr_stream *xdr,
 	encode_nfs4_stateid(xdr, &args->osa_stateid);
 }
 
+static void encode_offload_status(struct xdr_stream *xdr,
+				  const struct nfs42_offload_status_args *args,
+				  struct compound_hdr *hdr)
+{
+	encode_op_hdr(xdr, OP_OFFLOAD_STATUS, decode_offload_status_maxsz, hdr);
+	encode_nfs4_stateid(xdr, &args->osa_stateid);
+}
+
 static void encode_copy_notify(struct xdr_stream *xdr,
 			       const struct nfs42_copy_notify_args *args,
 			       struct compound_hdr *hdr)
@@ -549,7 +570,7 @@ static void nfs4_xdr_enc_copy(struct rpc_rqst *req,
 }
 
 /*
- * Encode OFFLOAD_CANEL request
+ * Encode OFFLOAD_CANCEL request
  */
 static void nfs4_xdr_enc_offload_cancel(struct rpc_rqst *req,
 					struct xdr_stream *xdr,
@@ -567,6 +588,25 @@ static void nfs4_xdr_enc_offload_cancel(struct rpc_rqst *req,
 	encode_nops(&hdr);
 }
 
+/*
+ * Encode OFFLOAD_STATUS request
+ */
+static void nfs4_xdr_enc_offload_status(struct rpc_rqst *req,
+					struct xdr_stream *xdr,
+					const void *data)
+{
+	const struct nfs42_offload_status_args *args = data;
+	struct compound_hdr hdr = {
+		.minorversion = nfs4_xdr_minorversion(&args->osa_seq_args),
+	};
+
+	encode_compound_hdr(xdr, req, &hdr);
+	encode_sequence(xdr, &args->osa_seq_args, &hdr);
+	encode_putfh(xdr, args->osa_src_fh, &hdr);
+	encode_offload_status(xdr, args, &hdr);
+	encode_nops(&hdr);
+}
+
 /*
  * Encode COPY_NOTIFY request
  */
@@ -919,6 +959,39 @@ static int decode_offload_cancel(struct xdr_stream *xdr,
 	return decode_op_hdr(xdr, OP_OFFLOAD_CANCEL);
 }
 
+static int decode_offload_status(struct xdr_stream *xdr,
+				 struct nfs42_offload_status_res *res)
+{
+	int status, count;
+	__be32 *p;
+
+	status = decode_op_hdr(xdr, OP_OFFLOAD_STATUS);
+	if (status)
+		return status;
+
+	/* osr_count */
+	p = xdr_inline_decode(xdr, 12);
+	if (unlikely(!p))
+		return -EIO;
+	p = xdr_decode_hyper(p, &res->osr_count);
+
+	res->completed = false;
+	count = be32_to_cpup(p);
+	if (unlikely(count > 1))
+		return -EIO;
+
+	if (count) {
+		/* osr_status */
+		p = xdr_inline_decode(xdr, 4);
+		if (unlikely(!p))
+			return -EIO;
+
+		res->completed = true;
+		res->osr_status = be32_to_cpup(p);
+	}
+	return 0;
+}
+
 static int decode_copy_notify(struct xdr_stream *xdr,
 			      struct nfs42_copy_notify_res *res)
 {
@@ -1368,6 +1441,32 @@ static int nfs4_xdr_dec_offload_cancel(struct rpc_rqst *rqstp,
 	return status;
 }
 
+/*
+ * Decode OFFLOAD_STATUS response
+ */
+static int nfs4_xdr_dec_offload_status(struct rpc_rqst *rqstp,
+				       struct xdr_stream *xdr,
+				       void *data)
+{
+	struct nfs42_offload_status_res *res = data;
+	struct compound_hdr hdr;
+	int status;
+
+	status = decode_compound_hdr(xdr, &hdr);
+	if (status)
+		goto out;
+	status = decode_sequence(xdr, &res->osr_seq_res, rqstp);
+	if (status)
+		goto out;
+	status = decode_putfh(xdr);
+	if (status)
+		goto out;
+	status = decode_offload_status(xdr, res);
+
+out:
+	return status;
+}
+
 /*
  * Decode COPY_NOTIFY response
  */
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 1416099dfcd1..bcb7de1c1b44 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -7711,6 +7711,7 @@ const struct rpc_procinfo nfs4_procedures[] = {
 	PROC42(CLONE,		enc_clone,		dec_clone),
 	PROC42(COPY,		enc_copy,		dec_copy),
 	PROC42(OFFLOAD_CANCEL,	enc_offload_cancel,	dec_offload_cancel),
+	PROC42(OFFLOAD_STATUS,	enc_offload_status,	dec_offload_status),
 	PROC42(COPY_NOTIFY,	enc_copy_notify,	dec_copy_notify),
 	PROC(LOOKUPP,		enc_lookupp,		dec_lookupp),
 	PROC42(LAYOUTERROR,	enc_layouterror,	dec_layouterror),
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index ef8d2d618d5b..89ed7dd29a9e 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -681,6 +681,7 @@ enum {
 	NFSPROC4_CLNT_LISTXATTRS,
 	NFSPROC4_CLNT_REMOVEXATTR,
 	NFSPROC4_CLNT_READ_PLUS,
+	NFSPROC4_CLNT_OFFLOAD_STATUS,
 };
 
 /* nfs41 types */
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index d09b9773b20c..7b55a4e506e1 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1490,6 +1490,7 @@ struct nfs42_offload_status_res {
 	struct nfs4_sequence_res	osr_seq_res;
 	uint64_t			osr_count;
 	int				osr_status;
+	bool				completed;
 };
 
 struct nfs42_copy_notify_args {
-- 
2.44.0