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
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.
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.
19 * See the file COPYING included with this distribution for more details.
25 #include <scsi/libiscsi.h>
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
33 /* xmit state machine */
34 #define XMSTATE_IDLE 0x0
35 #define XMSTATE_R_HDR 0x1
36 #define XMSTATE_W_HDR 0x2
37 #define XMSTATE_IMM_HDR 0x4
38 #define XMSTATE_IMM_DATA 0x8
39 #define XMSTATE_UNS_INIT 0x10
40 #define XMSTATE_UNS_HDR 0x20
41 #define XMSTATE_UNS_DATA 0x40
42 #define XMSTATE_SOL_HDR 0x80
43 #define XMSTATE_SOL_DATA 0x100
44 #define XMSTATE_W_PAD 0x200
45 #define XMSTATE_W_RESEND_PAD 0x400
46 #define XMSTATE_W_RESEND_DATA_DIGEST 0x800
48 #define ISCSI_PAD_LEN 4
49 #define ISCSI_SG_TABLESIZE SG_ALL
50 #define ISCSI_TCP_MAX_CMD_LEN 16
54 /* Socket connection recieve helper */
55 struct iscsi_tcp_recv
{
56 struct iscsi_hdr
*hdr
;
64 struct iscsi_cmd_task
*ctask
; /* current cmd in progress */
66 /* copied and flipped values */
72 struct iscsi_tcp_conn
{
73 struct iscsi_conn
*iscsi_conn
;
75 struct iscsi_hdr hdr
; /* header placeholder */
76 char hdrext
[4*sizeof(__u16
) +
79 int stop_stage
; /* conn_stop() flag: *
81 * stop to terminate */
82 /* iSCSI connection-wide sequencing */
83 int hdr_size
; /* PDU header size */
85 struct crypto_tfm
*rx_tfm
; /* CRC32C (Rx) */
86 struct crypto_tfm
*data_rx_tfm
; /* CRC32C (Rx) for data */
89 struct iscsi_tcp_recv in
; /* TCP receive context */
90 int in_progress
; /* connection state machine */
92 /* old values for socket callbacks */
93 void (*old_data_ready
)(struct sock
*, int);
94 void (*old_state_change
)(struct sock
*);
95 void (*old_write_space
)(struct sock
*);
98 struct crypto_tfm
*tx_tfm
; /* CRC32C (Tx) */
99 struct crypto_tfm
*data_tx_tfm
; /* CRC32C (Tx) for data */
101 /* MIB custom statistics */
102 uint32_t sendpage_failures_cnt
;
103 uint32_t discontiguous_hdr_cnt
;
105 ssize_t (*sendpage
)(struct socket
*, struct page
*, int, size_t, int);
109 struct scatterlist sg
;
114 struct iscsi_data_task
{
115 struct iscsi_data hdr
; /* PDU */
116 char hdrext
[sizeof(__u32
)]; /* Header-Digest */
117 struct iscsi_buf digestbuf
; /* digest buffer */
118 uint32_t digest
; /* data digest */
121 struct iscsi_tcp_mgmt_task
{
122 struct iscsi_hdr hdr
;
123 char hdrext
[sizeof(__u32
)]; /* Header-Digest */
124 int xmstate
; /* mgmt xmit progress */
125 struct iscsi_buf headbuf
; /* header buffer */
126 struct iscsi_buf sendbuf
; /* in progress buffer */
130 struct iscsi_r2t_info
{
131 __be32 ttt
; /* copied from R2T */
132 __be32 exp_statsn
; /* copied from R2T */
133 uint32_t data_length
; /* copied from R2T */
134 uint32_t data_offset
; /* copied from R2T */
135 struct iscsi_buf headbuf
; /* Data-Out Header Buffer */
136 struct iscsi_buf sendbuf
; /* Data-Out in progress buffer*/
137 int sent
; /* R2T sequence progress */
138 int data_count
; /* DATA-Out payload progress */
139 struct scatterlist
*sg
; /* per-R2T SG list */
141 struct iscsi_data_task dtask
; /* which data task */
144 struct iscsi_tcp_cmd_task
{
145 struct iscsi_cmd hdr
;
146 char hdrext
[4*sizeof(__u16
)+ /* AHS */
147 sizeof(__u32
)]; /* HeaderDigest */
148 char pad
[ISCSI_PAD_LEN
];
149 int pad_count
; /* padded bytes */
150 struct iscsi_buf headbuf
; /* header buf (xmit) */
151 struct iscsi_buf sendbuf
; /* in progress buffer*/
152 int xmstate
; /* xmit xtate machine */
154 struct scatterlist
*sg
; /* per-cmd SG list */
155 struct scatterlist
*bad_sg
; /* assert statement */
156 int sg_count
; /* SG's to process */
159 struct iscsi_r2t_info
*r2t
; /* in progress R2T */
160 struct iscsi_queue r2tpool
;
161 struct kfifo
*r2tqueue
;
162 struct iscsi_r2t_info
**r2ts
;
164 uint32_t immdigest
; /* for imm data */
165 struct iscsi_buf immbuf
; /* for imm data digest */
166 struct iscsi_data_task unsol_dtask
; /* unsol data task */