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 /* xmit state machine */
28 #define XMSTATE_IDLE 0x0
29 #define XMSTATE_CMD_HDR_INIT 0x1
30 #define XMSTATE_CMD_HDR_XMIT 0x2
31 #define XMSTATE_IMM_HDR 0x4
32 #define XMSTATE_IMM_DATA 0x8
33 #define XMSTATE_UNS_INIT 0x10
34 #define XMSTATE_UNS_HDR 0x20
35 #define XMSTATE_UNS_DATA 0x40
36 #define XMSTATE_SOL_HDR 0x80
37 #define XMSTATE_SOL_DATA 0x100
38 #define XMSTATE_W_PAD 0x200
39 #define XMSTATE_W_RESEND_PAD 0x400
40 #define XMSTATE_W_RESEND_DATA_DIGEST 0x800
41 #define XMSTATE_IMM_HDR_INIT 0x1000
42 #define XMSTATE_SOL_HDR_INIT 0x2000
44 #define ISCSI_PAD_LEN 4
45 #define ISCSI_SG_TABLESIZE SG_ALL
46 #define ISCSI_TCP_MAX_CMD_LEN 16
50 struct iscsi_tcp_conn;
53 typedef int iscsi_chunk_done_fn_t(struct iscsi_tcp_conn *,
54 struct iscsi_chunk *);
60 unsigned int total_size;
61 unsigned int total_copied;
63 struct hash_desc *hash;
64 unsigned char recv_digest[ISCSI_DIGEST_SIZE];
65 unsigned char digest[ISCSI_DIGEST_SIZE];
66 unsigned int digest_len;
68 struct scatterlist *sg;
70 unsigned int sg_offset;
71 unsigned int sg_index;
72 unsigned int sg_count;
74 iscsi_chunk_done_fn_t *done;
77 /* Socket connection recieve helper */
78 struct iscsi_tcp_recv {
79 struct iscsi_hdr *hdr;
80 struct iscsi_chunk chunk;
82 /* Allocate buffer for BHS + AHS */
85 /* copied and flipped values */
89 /* Socket connection send helper */
90 struct iscsi_tcp_send {
91 struct iscsi_hdr *hdr;
92 struct iscsi_chunk chunk;
93 struct iscsi_chunk data_chunk;
95 /* Allocate buffer for BHS + AHS */
99 struct iscsi_tcp_conn {
100 struct iscsi_conn *iscsi_conn;
102 int stop_stage; /* conn_stop() flag: *
104 * stop to terminate */
106 struct iscsi_tcp_recv in; /* TCP receive context */
107 struct iscsi_tcp_send out; /* TCP send context */
109 /* old values for socket callbacks */
110 void (*old_data_ready)(struct sock *, int);
111 void (*old_state_change)(struct sock *);
112 void (*old_write_space)(struct sock *);
114 /* data and header digests */
115 struct hash_desc tx_hash; /* CRC32C (Tx) */
116 struct hash_desc rx_hash; /* CRC32C (Rx) */
118 /* MIB custom statistics */
119 uint32_t sendpage_failures_cnt;
120 uint32_t discontiguous_hdr_cnt;
122 ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int);
126 struct scatterlist sg;
131 struct iscsi_data_task {
132 struct iscsi_data hdr; /* PDU */
133 char hdrext[sizeof(__u32)]; /* Header-Digest */
134 struct iscsi_buf digestbuf; /* digest buffer */
135 uint32_t digest; /* data digest */
138 struct iscsi_tcp_mgmt_task {
139 struct iscsi_hdr hdr;
140 char hdrext[sizeof(__u32)]; /* Header-Digest */
141 int xmstate; /* mgmt xmit progress */
142 struct iscsi_buf headbuf; /* header buffer */
143 struct iscsi_buf sendbuf; /* in progress buffer */
147 struct iscsi_r2t_info {
148 __be32 ttt; /* copied from R2T */
149 __be32 exp_statsn; /* copied from R2T */
150 uint32_t data_length; /* copied from R2T */
151 uint32_t data_offset; /* copied from R2T */
152 struct iscsi_buf headbuf; /* Data-Out Header Buffer */
153 struct iscsi_buf sendbuf; /* Data-Out in progress buffer*/
154 int sent; /* R2T sequence progress */
155 int data_count; /* DATA-Out payload progress */
156 struct scatterlist *sg; /* per-R2T SG list */
158 struct iscsi_data_task dtask; /* which data task */
161 struct iscsi_tcp_cmd_task {
162 struct iscsi_cmd hdr;
163 char hdrext[4*sizeof(__u16)+ /* AHS */
164 sizeof(__u32)]; /* HeaderDigest */
165 char pad[ISCSI_PAD_LEN];
166 int pad_count; /* padded bytes */
167 struct iscsi_buf headbuf; /* header buf (xmit) */
168 struct iscsi_buf sendbuf; /* in progress buffer*/
169 int xmstate; /* xmit xtate machine */
171 struct scatterlist *sg; /* per-cmd SG list */
172 struct scatterlist *bad_sg; /* assert statement */
173 int sg_count; /* SG's to process */
174 uint32_t exp_datasn; /* expected target's R2TSN/DataSN */
176 struct iscsi_r2t_info *r2t; /* in progress R2T */
177 struct iscsi_queue r2tpool;
178 struct kfifo *r2tqueue;
179 struct iscsi_r2t_info **r2ts;
181 uint32_t immdigest; /* for imm data */
182 struct iscsi_buf immbuf; /* for imm data digest */
183 struct iscsi_data_task unsol_dtask; /* unsol data task */