nvme-tcp: Add protocol header

Signed-off-by: Sagi Grimberg <sagi@lightbitslabs.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

2 files changed, 190 insertions, 0 deletions

diff --git a/include/linux/nvme-tcp.h b/include/linux/nvme-tcp.h
new file mode 100644
index 000000000000..03d87c0550a9
--- /dev/null
+++ b/include/linux/nvme-tcp.h
@@ -0,0 +1,189 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NVMe over Fabrics TCP protocol header.
+ * Copyright (c) 2018 Lightbits Labs. All rights reserved.
+ */
+
+#ifndef _LINUX_NVME_TCP_H
+#define _LINUX_NVME_TCP_H
+
+#include <linux/nvme.h>
+
+#define NVME_TCP_DISC_PORT	8009
+#define NVME_TCP_ADMIN_CCSZ	SZ_8K
+#define NVME_TCP_DIGEST_LENGTH	4
+
+enum nvme_tcp_pfv {
+	NVME_TCP_PFV_1_0 = 0x0,
+};
+
+enum nvme_tcp_fatal_error_status {
+	NVME_TCP_FES_INVALID_PDU_HDR		= 0x01,
+	NVME_TCP_FES_PDU_SEQ_ERR		= 0x02,
+	NVME_TCP_FES_HDR_DIGEST_ERR		= 0x03,
+	NVME_TCP_FES_DATA_OUT_OF_RANGE		= 0x04,
+	NVME_TCP_FES_R2T_LIMIT_EXCEEDED		= 0x05,
+	NVME_TCP_FES_DATA_LIMIT_EXCEEDED	= 0x05,
+	NVME_TCP_FES_UNSUPPORTED_PARAM		= 0x06,
+};
+
+enum nvme_tcp_digest_option {
+	NVME_TCP_HDR_DIGEST_ENABLE	= (1 << 0),
+	NVME_TCP_DATA_DIGEST_ENABLE	= (1 << 1),
+};
+
+enum nvme_tcp_pdu_type {
+	nvme_tcp_icreq		= 0x0,
+	nvme_tcp_icresp		= 0x1,
+	nvme_tcp_h2c_term	= 0x2,
+	nvme_tcp_c2h_term	= 0x3,
+	nvme_tcp_cmd		= 0x4,
+	nvme_tcp_rsp		= 0x5,
+	nvme_tcp_h2c_data	= 0x6,
+	nvme_tcp_c2h_data	= 0x7,
+	nvme_tcp_r2t		= 0x9,
+};
+
+enum nvme_tcp_pdu_flags {
+	NVME_TCP_F_HDGST		= (1 << 0),
+	NVME_TCP_F_DDGST		= (1 << 1),
+	NVME_TCP_F_DATA_LAST		= (1 << 2),
+	NVME_TCP_F_DATA_SUCCESS		= (1 << 3),
+};
+
+/**
+ * struct nvme_tcp_hdr - nvme tcp pdu common header
+ *
+ * @type:          pdu type
+ * @flags:         pdu specific flags
+ * @hlen:          pdu header length
+ * @pdo:           pdu data offset
+ * @plen:          pdu wire byte length
+ */
+struct nvme_tcp_hdr {
+	__u8	type;
+	__u8	flags;
+	__u8	hlen;
+	__u8	pdo;
+	__le32	plen;
+};
+
+/**
+ * struct nvme_tcp_icreq_pdu - nvme tcp initialize connection request pdu
+ *
+ * @hdr:           pdu generic header
+ * @pfv:           pdu version format
+ * @hpda:          host pdu data alignment (dwords, 0's based)
+ * @digest:        digest types enabled
+ * @maxr2t:        maximum r2ts per request supported
+ */
+struct nvme_tcp_icreq_pdu {
+	struct nvme_tcp_hdr	hdr;
+	__le16			pfv;
+	__u8			hpda;
+	__u8			digest;
+	__le32			maxr2t;
+	__u8			rsvd2[112];
+};
+
+/**
+ * struct nvme_tcp_icresp_pdu - nvme tcp initialize connection response pdu
+ *
+ * @hdr:           pdu common header
+ * @pfv:           pdu version format
+ * @cpda:          controller pdu data alignment (dowrds, 0's based)
+ * @digest:        digest types enabled
+ * @maxdata:       maximum data capsules per r2t supported
+ */
+struct nvme_tcp_icresp_pdu {
+	struct nvme_tcp_hdr	hdr;
+	__le16			pfv;
+	__u8			cpda;
+	__u8			digest;
+	__le32			maxdata;
+	__u8			rsvd[112];
+};
+
+/**
+ * struct nvme_tcp_term_pdu - nvme tcp terminate connection pdu
+ *
+ * @hdr:           pdu common header
+ * @fes:           fatal error status
+ * @fei:           fatal error information
+ */
+struct nvme_tcp_term_pdu {
+	struct nvme_tcp_hdr	hdr;
+	__le16			fes;
+	__le32			fei;
+	__u8			rsvd[8];
+};
+
+/**
+ * struct nvme_tcp_cmd_pdu - nvme tcp command capsule pdu
+ *
+ * @hdr:           pdu common header
+ * @cmd:           nvme command
+ */
+struct nvme_tcp_cmd_pdu {
+	struct nvme_tcp_hdr	hdr;
+	struct nvme_command	cmd;
+};
+
+/**
+ * struct nvme_tcp_rsp_pdu - nvme tcp response capsule pdu
+ *
+ * @hdr:           pdu common header
+ * @hdr:           nvme-tcp generic header
+ * @cqe:           nvme completion queue entry
+ */
+struct nvme_tcp_rsp_pdu {
+	struct nvme_tcp_hdr	hdr;
+	struct nvme_completion	cqe;
+};
+
+/**
+ * struct nvme_tcp_r2t_pdu - nvme tcp ready-to-transfer pdu
+ *
+ * @hdr:           pdu common header
+ * @command_id:    nvme command identifier which this relates to
+ * @ttag:          transfer tag (controller generated)
+ * @r2t_offset:    offset from the start of the command data
+ * @r2t_length:    length the host is allowed to send
+ */
+struct nvme_tcp_r2t_pdu {
+	struct nvme_tcp_hdr	hdr;
+	__u16			command_id;
+	__u16			ttag;
+	__le32			r2t_offset;
+	__le32			r2t_length;
+	__u8			rsvd[4];
+};
+
+/**
+ * struct nvme_tcp_data_pdu - nvme tcp data pdu
+ *
+ * @hdr:           pdu common header
+ * @command_id:    nvme command identifier which this relates to
+ * @ttag:          transfer tag (controller generated)
+ * @data_offset:   offset from the start of the command data
+ * @data_length:   length of the data stream
+ */
+struct nvme_tcp_data_pdu {
+	struct nvme_tcp_hdr	hdr;
+	__u16			command_id;
+	__u16			ttag;
+	__le32			data_offset;
+	__le32			data_length;
+	__u8			rsvd[4];
+};
+
+union nvme_tcp_pdu {
+	struct nvme_tcp_icreq_pdu	icreq;
+	struct nvme_tcp_icresp_pdu	icresp;
+	struct nvme_tcp_cmd_pdu		cmd;
+	struct nvme_tcp_rsp_pdu		rsp;
+	struct nvme_tcp_r2t_pdu		r2t;
+	struct nvme_tcp_data_pdu	data;
+};
+
+#endif /* _LINUX_NVME_TCP_H */
diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 88812cb15be0..4d7907e3771e 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -52,6 +52,7 @@ enum {
 enum {
 	NVMF_TRTYPE_RDMA	= 1,	/* RDMA */
 	NVMF_TRTYPE_FC		= 2,	/* Fibre Channel */
+	NVMF_TRTYPE_TCP		= 3,	/* TCP/IP */
 	NVMF_TRTYPE_LOOP	= 254,	/* Reserved for host usage */
 	NVMF_TRTYPE_MAX,
 };