[deliverable/linux.git] / drivers / scsi / iscsi_tcp.h

/*
 * iSCSI Initiator TCP Transport
 * Copyright (C) 2004 Dmitry Yusupov
 * Copyright (C) 2004 Alex Aizman
 * Copyright (C) 2005 - 2006 Mike Christie
 * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
 * maintained by open-iscsi@googlegroups.com
 *
 * 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

#include <scsi/libiscsi.h>

/* 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
#define IN_PROGRESS_PAD_RECV		0x4

/* xmit state machine */
#define XMSTATE_IDLE			0x0
#define XMSTATE_CMD_HDR_INIT		0x1
#define XMSTATE_CMD_HDR_XMIT		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_W_RESEND_PAD		0x400
#define XMSTATE_W_RESEND_DATA_DIGEST	0x800
#define XMSTATE_IMM_HDR_INIT		0x1000
#define XMSTATE_SOL_HDR_INIT		0x2000

#define ISCSI_PAD_LEN			4
#define ISCSI_SG_TABLESIZE		SG_ALL
#define ISCSI_TCP_MAX_CMD_LEN		16

struct crypto_hash;
struct socket;

/* 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			datalen;
	int			datadgst;
	char			zero_copy_hdr;
};

struct iscsi_tcp_conn {
	struct iscsi_conn	*iscsi_conn;
	struct socket		*sock;
	struct iscsi_hdr	hdr;		/* header placeholder */
	char			hdrext[4*sizeof(__u16) +
				    sizeof(__u32)];
	int			data_copied;
	int			stop_stage;	/* conn_stop() flag: *
						 * stop to recover,  *
						 * stop to terminate */
	/* iSCSI connection-wide sequencing */
	int			hdr_size;	/* PDU header size */

	/* control data */
	struct iscsi_tcp_recv	in;		/* TCP receive context */
	int			in_progress;	/* connection state machine */

	/* old values for socket callbacks */
	void			(*old_data_ready)(struct sock *, int);
	void			(*old_state_change)(struct sock *);
	void			(*old_write_space)(struct sock *);

	/* data and header digests */
	struct hash_desc	tx_hash;	/* CRC32C (Tx) */
	struct hash_desc	rx_hash;	/* CRC32C (Rx) */

	/* MIB custom statistics */
	uint32_t		sendpage_failures_cnt;
	uint32_t		discontiguous_hdr_cnt;

	ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int);
};

struct iscsi_buf {
	struct scatterlist	sg;
	unsigned int		sent;
	char			use_sendmsg;
};

struct iscsi_data_task {
	struct iscsi_data	hdr;			/* PDU */
	char			hdrext[sizeof(__u32)];	/* Header-Digest */
	struct iscsi_buf	digestbuf;		/* digest buffer */
	uint32_t		digest;			/* data digest */
};

struct iscsi_tcp_mgmt_task {
	struct iscsi_hdr	hdr;
	char			hdrext[sizeof(__u32)]; /* Header-Digest */
	int			xmstate;	/* mgmt xmit progress */
	struct iscsi_buf	headbuf;	/* header buffer */
	struct iscsi_buf	sendbuf;	/* in progress buffer */
	int			sent;
};

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_tcp_cmd_task {
	struct iscsi_cmd	hdr;
	char			hdrext[4*sizeof(__u16)+	/* AHS */
				    sizeof(__u32)];	/* HeaderDigest */
	char			pad[ISCSI_PAD_LEN];
	int			pad_count;		/* padded bytes */
	struct iscsi_buf	headbuf;		/* header buf (xmit) */
	struct iscsi_buf	sendbuf;		/* in progress buffer*/
	int			xmstate;		/* xmit xtate machine */
	int			sent;
	struct scatterlist	*sg;			/* per-cmd SG list  */
	struct scatterlist	*bad_sg;		/* assert statement */
	int			sg_count;		/* SG's to process  */
	uint32_t		exp_datasn;		/* expected target's R2TSN/DataSN */
	int			data_offset;
	struct iscsi_r2t_info	*r2t;			/* in progress R2T    */
	struct iscsi_queue	r2tpool;
	struct kfifo		*r2tqueue;
	struct iscsi_r2t_info	**r2ts;
	int			digest_count;
	uint32_t		immdigest;		/* for imm data */
	struct iscsi_buf	immbuf;			/* for imm data digest */
	struct iscsi_data_task	unsol_dtask;	/* unsol data task */
};

#endif /* ISCSI_H */
Commit	Line	Data
	1	/*
	2	* iSCSI Initiator TCP Transport
	3	* Copyright (C) 2004 Dmitry Yusupov
	4	* Copyright (C) 2004 Alex Aizman
	5	* Copyright (C) 2005 - 2006 Mike Christie
	6	* Copyright (C) 2006 Red Hat, Inc. All rights reserved.
	7	* maintained by open-iscsi@googlegroups.com
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License as published
	11	* by the Free Software Foundation; either version 2 of the License, or
	12	* (at your option) any later version.
	13	*
	14	* This program is distributed in the hope that it will be useful, but
	15	* WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	17	* General Public License for more details.
	18	*
	19	* See the file COPYING included with this distribution for more details.
	20	*/
	21
	22	#ifndef ISCSI_TCP_H
	23	#define ISCSI_TCP_H
	24
	25	#include <scsi/libiscsi.h>
	26
	27	/* Socket's Receive state machine */
	28	#define IN_PROGRESS_WAIT_HEADER 0x0
	29	#define IN_PROGRESS_HEADER_GATHER 0x1
	30	#define IN_PROGRESS_DATA_RECV 0x2
	31	#define IN_PROGRESS_DDIGEST_RECV 0x3
	32	#define IN_PROGRESS_PAD_RECV 0x4
	33
	34	/* xmit state machine */
	35	#define XMSTATE_IDLE 0x0
	36	#define XMSTATE_CMD_HDR_INIT 0x1
	37	#define XMSTATE_CMD_HDR_XMIT 0x2
	38	#define XMSTATE_IMM_HDR 0x4
	39	#define XMSTATE_IMM_DATA 0x8
	40	#define XMSTATE_UNS_INIT 0x10
	41	#define XMSTATE_UNS_HDR 0x20
	42	#define XMSTATE_UNS_DATA 0x40
	43	#define XMSTATE_SOL_HDR 0x80
	44	#define XMSTATE_SOL_DATA 0x100
	45	#define XMSTATE_W_PAD 0x200
	46	#define XMSTATE_W_RESEND_PAD 0x400
	47	#define XMSTATE_W_RESEND_DATA_DIGEST 0x800
	48	#define XMSTATE_IMM_HDR_INIT 0x1000
	49	#define XMSTATE_SOL_HDR_INIT 0x2000
	50
	51	#define ISCSI_PAD_LEN 4
	52	#define ISCSI_SG_TABLESIZE SG_ALL
	53	#define ISCSI_TCP_MAX_CMD_LEN 16
	54
	55	struct crypto_hash;
	56	struct socket;
	57
	58	/* Socket connection recieve helper */
	59	struct iscsi_tcp_recv {
	60	struct iscsi_hdr *hdr;
	61	struct sk_buff *skb;
	62	int offset;
	63	int len;
	64	int hdr_offset;
	65	int copy;
	66	int copied;
	67	int padding;
	68	struct iscsi_cmd_task ctask; / current cmd in progress */
	69
	70	/* copied and flipped values */
	71	int datalen;
	72	int datadgst;
	73	char zero_copy_hdr;
	74	};
	75
	76	struct iscsi_tcp_conn {
	77	struct iscsi_conn *iscsi_conn;
	78	struct socket *sock;
	79	struct iscsi_hdr hdr; /* header placeholder */
	80	char hdrext[4*sizeof(__u16) +
	81	sizeof(__u32)];
	82	int data_copied;
	83	int stop_stage; /* conn_stop() flag: *
	84	* stop to recover, *
	85	* stop to terminate */
	86	/* iSCSI connection-wide sequencing */
	87	int hdr_size; /* PDU header size */
	88
	89	/* control data */
	90	struct iscsi_tcp_recv in; /* TCP receive context */
	91	int in_progress; /* connection state machine */
	92
	93	/* old values for socket callbacks */
	94	void (old_data_ready)(struct sock , int);
	95	void (old_state_change)(struct sock );
	96	void (old_write_space)(struct sock );
	97
	98	/* data and header digests */
	99	struct hash_desc tx_hash; /* CRC32C (Tx) */
	100	struct hash_desc rx_hash; /* CRC32C (Rx) */
	101
	102	/* MIB custom statistics */
	103	uint32_t sendpage_failures_cnt;
	104	uint32_t discontiguous_hdr_cnt;
	105
	106	ssize_t (sendpage)(struct socket , struct page *, int, size_t, int);
	107	};
	108
	109	struct iscsi_buf {
	110	struct scatterlist sg;
	111	unsigned int sent;
	112	char use_sendmsg;
	113	};
	114
	115	struct iscsi_data_task {
	116	struct iscsi_data hdr; /* PDU */
	117	char hdrext[sizeof(__u32)]; /* Header-Digest */
	118	struct iscsi_buf digestbuf; /* digest buffer */
	119	uint32_t digest; /* data digest */
	120	};
	121
	122	struct iscsi_tcp_mgmt_task {
	123	struct iscsi_hdr hdr;
	124	char hdrext[sizeof(__u32)]; /* Header-Digest */
	125	int xmstate; /* mgmt xmit progress */
	126	struct iscsi_buf headbuf; /* header buffer */
	127	struct iscsi_buf sendbuf; /* in progress buffer */
	128	int sent;
	129	};
	130
	131	struct iscsi_r2t_info {
	132	__be32 ttt; /* copied from R2T */
	133	__be32 exp_statsn; /* copied from R2T */
	134	uint32_t data_length; /* copied from R2T */
	135	uint32_t data_offset; /* copied from R2T */
	136	struct iscsi_buf headbuf; /* Data-Out Header Buffer */
	137	struct iscsi_buf sendbuf; /* Data-Out in progress buffer*/
	138	int sent; /* R2T sequence progress */
	139	int data_count; /* DATA-Out payload progress */
	140	struct scatterlist sg; / per-R2T SG list */
	141	int solicit_datasn;
	142	struct iscsi_data_task dtask; /* which data task */
	143	};
	144
	145	struct iscsi_tcp_cmd_task {
	146	struct iscsi_cmd hdr;
	147	char hdrext[4sizeof(__u16)+ / AHS */
	148	sizeof(__u32)]; /* HeaderDigest */
	149	char pad[ISCSI_PAD_LEN];
	150	int pad_count; /* padded bytes */
	151	struct iscsi_buf headbuf; /* header buf (xmit) */
	152	struct iscsi_buf sendbuf; /* in progress buffer*/
	153	int xmstate; /* xmit xtate machine */
	154	int sent;
	155	struct scatterlist sg; / per-cmd SG list */
	156	struct scatterlist bad_sg; / assert statement */
	157	int sg_count; /* SG's to process */
	158	uint32_t exp_datasn; /* expected target's R2TSN/DataSN */
	159	int data_offset;
	160	struct iscsi_r2t_info r2t; / in progress R2T */
	161	struct iscsi_queue r2tpool;
	162	struct kfifo *r2tqueue;
	163	struct iscsi_r2t_info **r2ts;
	164	int digest_count;
	165	uint32_t immdigest; /* for imm data */
	166	struct iscsi_buf immbuf; /* for imm data digest */
	167	struct iscsi_data_task unsol_dtask; /* unsol data task */
	168	};
	169
	170	#endif /* ISCSI_H */