linux/drivers/scsi/iscsi_tcp.h

134 lines
3.5 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>
struct crypto_hash;
struct socket;
struct iscsi_tcp_conn;
struct iscsi_segment;
typedef int iscsi_segment_done_fn_t(struct iscsi_tcp_conn *,
struct iscsi_segment *);
struct iscsi_segment {
unsigned char *data;
unsigned int size;
unsigned int copied;
unsigned int total_size;
unsigned int total_copied;
struct hash_desc *hash;
unsigned char recv_digest[ISCSI_DIGEST_SIZE];
unsigned char digest[ISCSI_DIGEST_SIZE];
unsigned int digest_len;
struct scatterlist *sg;
void *sg_mapped;
unsigned int sg_offset;
iscsi_segment_done_fn_t *done;
};
/* Socket connection recieve helper */
struct iscsi_tcp_recv {
struct iscsi_hdr *hdr;
struct iscsi_segment segment;
/* Allocate buffer for BHS + AHS */
uint32_t hdr_buf[64];
/* copied and flipped values */
int datalen;
};
/* Socket connection send helper */
struct iscsi_tcp_send {
struct iscsi_hdr *hdr;
struct iscsi_segment segment;
struct iscsi_segment data_segment;
};
struct iscsi_tcp_conn {
struct iscsi_conn *iscsi_conn;
struct socket *sock;
int stop_stage; /* conn_stop() flag: *
* stop to recover, *
* stop to terminate */
/* control data */
struct iscsi_tcp_recv in; /* TCP receive context */
struct iscsi_tcp_send out; /* TCP send context */
/* 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;
int error;
ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int);
};
struct iscsi_data_task {
struct iscsi_data hdr; /* PDU */
char hdrext[ISCSI_DIGEST_SIZE];/* Header-Digest */
};
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 */
int sent; /* R2T sequence progress */
int data_count; /* DATA-Out payload progress */
int solicit_datasn;
struct iscsi_data_task dtask; /* Data-Out header buf */
};
struct iscsi_tcp_task {
struct iscsi_hdr_buff {
struct iscsi_cmd cmd_hdr;
char hdrextbuf[ISCSI_MAX_AHS_SIZE +
ISCSI_DIGEST_SIZE];
} hdr;
int sent;
uint32_t exp_datasn; /* expected target's R2TSN/DataSN */
int data_offset;
struct iscsi_r2t_info *r2t; /* in progress R2T */
struct iscsi_pool r2tpool;
struct kfifo *r2tqueue;
struct iscsi_data_task unsol_dtask; /* Data-Out header buf */
};
#endif /* ISCSI_H */