linux/drivers/scsi/iscsi_tcp.h

178 lines
5.3 KiB
C

/*
* 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
/* 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_RCVBUF_MIN 262144
#define ISCSI_CONN_SNDBUF_MIN 262144
#define ISCSI_PAD_LEN 4
#define ISCSI_R2T_MAX 16
#define ISCSI_SG_TABLESIZE SG_ALL
#define ISCSI_TCP_MAX_CMD_LEN 16
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;
char *data; /* data placeholder */
int data_size; /* actual recv_dlength */
int stop_stage; /* conn_stop() flag: *
* stop to recover, *
* stop to terminate */
/* iSCSI connection-wide sequencing */
int hdr_size; /* PDU header size */
struct crypto_tfm *rx_tfm; /* CRC32C (Rx) */
struct crypto_tfm *data_rx_tfm; /* CRC32C (Rx) for data */
/* 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 *);
/* xmit */
struct crypto_tfm *tx_tfm; /* CRC32C (Tx) */
struct crypto_tfm *data_tx_tfm; /* CRC32C (Tx) for data */
/* 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_r2tsn;
int r2t_data_count; /* R2T Data-Out bytes */
int data_offset;
struct iscsi_r2t_info *r2t; /* in progress R2T */
struct iscsi_queue r2tpool;
struct kfifo *r2tqueue;
struct iscsi_r2t_info **r2ts;
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*/
struct iscsi_data_task unsol_dtask; /* unsol data task */
int digest_offset; /* for partial buff digest */
};
#endif /* ISCSI_H */