open-iscsi/linux-iscsi-5 Initiator: open-iscsi-tcp.h.patch

new file mode 100644
@@ -0,0 +1,322 @@
+/*
+ * iSCSI Initiator TCP Transport
+ * Copyright (C) 2004 Dmitry Yusupov
+ * Copyright (C) 2004 Alex Aizman
+ * Copyright (C) 2005 Mike Christie
+ * maintained by [email protected]
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * See the file COPYING included with this distribution for more details.
+ */
+
+#ifndef ISCSI_TCP_H
+#define ISCSI_TCP_H
+
+/* Session's states */
+#define ISCSI_STATE_FREE		1
+#define ISCSI_STATE_LOGGED_IN		2
+#define ISCSI_STATE_FAILED		3
+#define ISCSI_STATE_TERMINATE		4
+
+/* Connection's states */
+#define ISCSI_CONN_INITIAL_STAGE	0
+#define ISCSI_CONN_STARTED		1
+#define ISCSI_CONN_STOPPED		2
+#define ISCSI_CONN_CLEANUP_WAIT		3
+
+/* Connection suspend "bit" */
+#define SUSPEND_BIT			1
+
+/* Socket's Receive state machine */
+#define IN_PROGRESS_WAIT_HEADER		0x0
+#define IN_PROGRESS_HEADER_GATHER	0x1
+#define IN_PROGRESS_DATA_RECV		0x2
+#define IN_PROGRESS_DDIGEST_RECV	0x3
+
+/* Task Mgmt states */
+#define	TMABORT_INITIAL			0x0
+#define	TMABORT_SUCCESS			0x1
+#define	TMABORT_FAILED			0x2
+#define	TMABORT_TIMEDOUT		0x3
+
+/* xmit state machine */
+#define	XMSTATE_IDLE			0x0
+#define	XMSTATE_R_HDR			0x1
+#define	XMSTATE_W_HDR			0x2
+#define	XMSTATE_IMM_HDR			0x4
+#define	XMSTATE_IMM_DATA		0x8
+#define	XMSTATE_UNS_INIT		0x10
+#define	XMSTATE_UNS_HDR			0x20
+#define	XMSTATE_UNS_DATA		0x40
+#define	XMSTATE_SOL_HDR			0x80
+#define	XMSTATE_SOL_DATA		0x100
+#define	XMSTATE_W_PAD			0x200
+#define XMSTATE_DATA_DIGEST		0x400
+
+#define ISCSI_CONN_MAX			1
+#define ISCSI_CONN_RCVBUF_MIN		262144
+#define ISCSI_CONN_SNDBUF_MIN		262144
+#define ISCSI_PAD_LEN			4
+#define ISCSI_R2T_MAX			16
+#define ISCSI_XMIT_CMDS_MAX		128	/* must be power of 2 */
+#define ISCSI_MGMT_CMDS_MAX		32	/* must be power of 2 */
+#define ISCSI_MGMT_ITT_OFFSET		0xa00
+#define ISCSI_SG_TABLESIZE		SG_ALL
+#define ISCSI_CMD_PER_LUN		128
+#define ISCSI_TCP_MAX_CMD_LEN		16
+
+#define ITT_MASK			(0xfff)
+#define CID_SHIFT			12
+#define CID_MASK			(0xffff<<CID_SHIFT)
+#define AGE_SHIFT			28
+#define AGE_MASK			(0xf<<AGE_SHIFT)
+
+struct iscsi_queue {
+	struct kfifo		*queue;		/* FIFO Queue */
+	void			**pool;		/* Pool of elements */
+	int			max;		/* Max number of elements */
+};
+
+struct iscsi_session;
+struct iscsi_cmd_task;
+struct iscsi_mgmt_task;
+
+/* Socket connection recieve helper */
+struct iscsi_tcp_recv {
+	struct iscsi_hdr	*hdr;
+	struct sk_buff		*skb;
+	int			offset;
+	int			len;
+	int			hdr_offset;
+	int			copy;
+	int			copied;
+	int			padding;
+	struct iscsi_cmd_task	*ctask;		/* current cmd in progress */
+
+	/* copied and flipped values */
+	int			opcode;
+	int			flags;
+	int			cmd_status;
+	int			ahslen;
+	int			datalen;
+	uint32_t		itt;
+	int			datadgst;
+};
+
+struct iscsi_conn {
+	struct iscsi_hdr	hdr;		/* header placeholder */
+	char			hdrext[4*sizeof(__u16) +
+				    sizeof(__u32)];
+	int			data_copied;
+	char			*data;		/* data placeholder */
+	struct socket           *sock;          /* TCP socket */
+	int			data_size;	/* actual recv_dlength */
+	int			stop_stage;	/* conn_stop() flag: *
+						 * stop to recover,  *
+						 * stop to terminate */
+	/* iSCSI connection-wide sequencing */
+	uint32_t		exp_statsn;
+	int			hdr_size;	/* PDU header size */
+	unsigned long		suspend_rx;	/* suspend Rx */
+
+	struct crypto_tfm	*rx_tfm;	/* CRC32C (Rx) */
+	struct crypto_tfm	*data_rx_tfm;	/* CRC32C (Rx) for data */
+
+	/* control data */
+	int			senselen;	/* scsi sense length */
+	int			id;		/* CID */
+	struct iscsi_tcp_recv	in;		/* TCP receive context */
+	struct iscsi_session	*session;	/* parent session */
+	struct list_head	item;		/* maintains list of conns */
+	int			in_progress;	/* connection state machine */
+	int			c_stage;	/* connection state */
+	struct iscsi_mgmt_task	*login_mtask;	/* mtask used for login/text */
+	struct iscsi_mgmt_task	*mtask;		/* xmit mtask in progress */
+	struct iscsi_cmd_task	*ctask;		/* xmit ctask in progress */
+	spinlock_t		lock;		/* FIXME: to be removed */
+
+	/* old values for socket callbacks */
+	void			(*old_data_ready)(struct sock *, int);
+	void			(*old_state_change)(struct sock *);
+	void			(*old_write_space)(struct sock *);
+
+	/* xmit */
+	struct crypto_tfm	*tx_tfm;	/* CRC32C (Tx) */
+	struct crypto_tfm	*data_tx_tfm;	/* CRC32C (Tx) for data */
+	struct kfifo		*writequeue;	/* write cmds for Data-Outs */
+	struct kfifo		*immqueue;	/* immediate xmit queue */
+	struct kfifo		*mgmtqueue;	/* mgmt (control) xmit queue */
+	struct kfifo		*xmitqueue;	/* data-path cmd queue */
+	struct work_struct	xmitwork;	/* per-conn. xmit workqueue */
+	struct semaphore	xmitsema;	/* serializes connection xmit,
+						 * access to kfifos:	  *
+						 * xmitqueue, writequeue, *
+						 * immqueue, mgmtqueue    */
+	unsigned long		suspend_tx;	/* suspend Tx */
+
+	/* abort */
+	wait_queue_head_t	ehwait;		/* used in eh_abort()     */
+	struct iscsi_tm		tmhdr;
+	struct timer_list	tmabort_timer;  /* abort timer */
+	int			tmabort_state;  /* see TMABORT_INITIAL, etc.*/
+
+	/* negotiated params */
+	int			max_recv_dlength;
+	int			max_xmit_dlength;
+	int			hdrdgst_en;
+	int			datadgst_en;
+
+	/* MIB-statistics */
+	uint64_t		txdata_octets;
+	uint64_t		rxdata_octets;
+	uint32_t		scsicmd_pdus_cnt;
+	uint32_t		dataout_pdus_cnt;
+	uint32_t		scsirsp_pdus_cnt;
+	uint32_t		datain_pdus_cnt;
+	uint32_t		r2t_pdus_cnt;
+	uint32_t		tmfcmd_pdus_cnt;
+	int32_t			tmfrsp_pdus_cnt;
+
+	/* custom statistics */
+	uint32_t		sendpage_failures_cnt;
+	uint32_t		discontiguous_hdr_cnt;
+	uint32_t		eh_abort_cnt;
+};
+
+struct iscsi_session {
+	/* iSCSI session-wide sequencing */
+	uint32_t		cmdsn;
+	uint32_t		exp_cmdsn;
+	uint32_t		max_cmdsn;
+
+	/* configuration */
+	int			initial_r2t_en;
+	int			max_r2t;
+	int			imm_data_en;
+	int			first_burst;
+	int			max_burst;
+	int			time2wait;
+	int			time2retain;
+	int			pdu_inorder_en;
+	int			dataseq_inorder_en;
+	int			erl;
+	int			ifmarker_en;
+	int			ofmarker_en;
+
+	/* control data */
+	struct Scsi_Host	*host;
+	int			id;
+	struct iscsi_conn	*leadconn;	/* leading connection */
+	spinlock_t		lock;		/* protects session state, *
+						 * sequence numbers,       *
+						 * session resources:      *
+						 * - cmdpool,		   *
+						 * - mgmtpool,		   *
+						 * - r2tpool		   */
+	int			state;		/* session state           */
+	struct list_head	item;
+	void			*auth_client;
+	int			conn_cnt;
+	int			age;		/* counts session re-opens */
+
+	struct list_head	connections;	/* list of connections */
+	int			cmds_max;	/* size of cmds array */
+	struct iscsi_cmd_task	**cmds;		/* Original Cmds arr */
+	struct iscsi_queue	cmdpool;	/* PDU's pool */
+	int			mgmtpool_max;	/* size of mgmt array */
+	struct iscsi_mgmt_task	**mgmt_cmds;	/* Original mgmt arr */
+	struct iscsi_queue	mgmtpool;	/* Mgmt PDU's pool */
+};
+
+struct iscsi_buf {
+	struct scatterlist	sg;
+	struct kvec		iov;
+	unsigned int		sent;
+};
+
+struct iscsi_data_task {
+	struct iscsi_data	hdr;			/* PDU */
+	char			hdrext[sizeof(__u32)];	/* Header-Digest */
+	struct list_head	item;			/* data queue item */
+	struct iscsi_buf	digestbuf;		/* digest buffer */
+	uint32_t		digest;			/* data digest */
+};
+#define ISCSI_DTASK_DEFAULT_MAX	ISCSI_SG_TABLESIZE * PAGE_SIZE / 512
+
+struct iscsi_mgmt_task {
+	struct iscsi_hdr	hdr;		/* mgmt. PDU */
+	char			hdrext[sizeof(__u32)];	/* Header-Digest */
+	char			*data;		/* mgmt payload */
+	int			xmstate;	/* mgmt xmit progress */
+	int			data_count;	/* counts data to be sent */
+	struct iscsi_buf	headbuf;	/* header buffer */
+	struct iscsi_buf	sendbuf;	/* in progress buffer */
+	int			sent;
+	uint32_t		itt;		/* this ITT */
+};
+
+struct iscsi_r2t_info {
+	__be32			ttt;		/* copied from R2T */
+	__be32			exp_statsn;	/* copied from R2T */
+	uint32_t		data_length;	/* copied from R2T */
+	uint32_t		data_offset;	/* copied from R2T */
+	struct iscsi_buf	headbuf;	/* Data-Out Header Buffer */
+	struct iscsi_buf	sendbuf;	/* Data-Out in progress buffer*/
+	int			sent;		/* R2T sequence progress */
+	int			data_count;	/* DATA-Out payload progress */
+	struct scatterlist	*sg;		/* per-R2T SG list */
+	int			solicit_datasn;
+	struct iscsi_data_task   *dtask;        /* which data task */
+};
+
+struct iscsi_cmd_task {
+	struct iscsi_cmd	hdr;			/* iSCSI PDU header */
+	char			hdrext[4*sizeof(__u16)+	/* AHS */
+				    sizeof(__u32)];	/* HeaderDigest */
+	char			pad[ISCSI_PAD_LEN];
+	int			itt;			/* this ITT */
+	int			datasn;			/* DataSN */
+	struct iscsi_buf	headbuf;		/* header buf (xmit) */
+	struct iscsi_buf	sendbuf;		/* in progress buffer*/
+	int			sent;
+	struct scatterlist	*sg;			/* per-cmd SG list  */
+	struct scatterlist	*bad_sg;		/* assert statement */
+	int			sg_count;		/* SG's to process  */
+	uint32_t		unsol_datasn;
+	uint32_t		exp_r2tsn;
+	int			xmstate;		/* xmit xtate machine */
+	int			imm_count;		/* imm-data (bytes)   */
+	int			unsol_count;		/* unsolicited (bytes)*/
+	int			r2t_data_count;		/* R2T Data-Out bytes */
+	int			data_count;		/* remaining Data-Out */
+	int			pad_count;		/* padded bytes */
+	struct scsi_cmnd	*sc;			/* associated SCSI cmd*/
+	int			total_length;
+	int			data_offset;
+	struct iscsi_conn	*conn;			/* used connection    */
+	struct iscsi_mgmt_task	*mtask;			/* tmf mtask in progr */
+
+	struct iscsi_r2t_info	*r2t;			/* in progress R2T    */
+	struct iscsi_queue	r2tpool;
+	struct kfifo		*r2tqueue;
+	struct iscsi_r2t_info	**r2ts;
+	struct list_head	dataqueue;		/* Data-Out dataqueue */
+	mempool_t		*datapool;
+	uint32_t		datadigest;		/* for recover digest */
+	int			digest_count;
+	uint32_t		immdigest;		/* for imm data */
+	struct iscsi_buf	immbuf;			/* for imm data digest */
+	struct iscsi_data_task   *dtask;		/* data task in progress*/
+	int			digest_offset;		/* for partial buff digest */
+};
+
+#endif /* ISCSI_H */