2 * iSCSI Initiator TCP Transport
3 * Copyright (C) 2004 Dmitry Yusupov
4 * Copyright (C) 2004 Alex Aizman
5 * Copyright (C) 2005 Mike Christie
6 * maintained by open-iscsi@googlegroups.com
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published
10 * by the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * See the file COPYING included with this distribution for more details.
24 /* Session's states */
25 #define ISCSI_STATE_FREE 1
26 #define ISCSI_STATE_LOGGED_IN 2
27 #define ISCSI_STATE_FAILED 3
28 #define ISCSI_STATE_TERMINATE 4
30 /* Connection's states */
31 #define ISCSI_CONN_INITIAL_STAGE 0
32 #define ISCSI_CONN_STARTED 1
33 #define ISCSI_CONN_STOPPED 2
34 #define ISCSI_CONN_CLEANUP_WAIT 3
36 /* Connection suspend "bit" */
39 /* Socket's Receive state machine */
40 #define IN_PROGRESS_WAIT_HEADER 0x0
41 #define IN_PROGRESS_HEADER_GATHER 0x1
42 #define IN_PROGRESS_DATA_RECV 0x2
43 #define IN_PROGRESS_DDIGEST_RECV 0x3
45 /* Task Mgmt states */
46 #define TMABORT_INITIAL 0x0
47 #define TMABORT_SUCCESS 0x1
48 #define TMABORT_FAILED 0x2
49 #define TMABORT_TIMEDOUT 0x3
51 /* xmit state machine */
52 #define XMSTATE_IDLE 0x0
53 #define XMSTATE_R_HDR 0x1
54 #define XMSTATE_W_HDR 0x2
55 #define XMSTATE_IMM_HDR 0x4
56 #define XMSTATE_IMM_DATA 0x8
57 #define XMSTATE_UNS_INIT 0x10
58 #define XMSTATE_UNS_HDR 0x20
59 #define XMSTATE_UNS_DATA 0x40
60 #define XMSTATE_SOL_HDR 0x80
61 #define XMSTATE_SOL_DATA 0x100
62 #define XMSTATE_W_PAD 0x200
63 #define XMSTATE_DATA_DIGEST 0x400
65 #define ISCSI_CONN_MAX 1
66 #define ISCSI_CONN_RCVBUF_MIN 262144
67 #define ISCSI_CONN_SNDBUF_MIN 262144
68 #define ISCSI_PAD_LEN 4
69 #define ISCSI_R2T_MAX 16
70 #define ISCSI_XMIT_CMDS_MAX 128 /* must be power of 2 */
71 #define ISCSI_MGMT_CMDS_MAX 32 /* must be power of 2 */
72 #define ISCSI_MGMT_ITT_OFFSET 0xa00
73 #define ISCSI_SG_TABLESIZE SG_ALL
74 #define ISCSI_CMD_PER_LUN 128
75 #define ISCSI_TCP_MAX_CMD_LEN 16
77 #define ITT_MASK (0xfff)
79 #define CID_MASK (0xffff<<CID_SHIFT)
81 #define AGE_MASK (0xf<<AGE_SHIFT)
84 struct kfifo
*queue
; /* FIFO Queue */
85 void **pool
; /* Pool of elements */
86 int max
; /* Max number of elements */
90 struct iscsi_cmd_task
;
91 struct iscsi_mgmt_task
;
93 /* Socket connection recieve helper */
94 struct iscsi_tcp_recv
{
95 struct iscsi_hdr
*hdr
;
103 struct iscsi_cmd_task
*ctask
; /* current cmd in progress */
105 /* copied and flipped values */
116 struct iscsi_hdr hdr
; /* header placeholder */
117 char hdrext
[4*sizeof(__u16
) +
120 char *data
; /* data placeholder */
121 struct socket
*sock
; /* TCP socket */
122 int data_size
; /* actual recv_dlength */
123 int stop_stage
; /* conn_stop() flag: *
125 * stop to terminate */
126 /* iSCSI connection-wide sequencing */
128 int hdr_size
; /* PDU header size */
129 unsigned long suspend_rx
; /* suspend Rx */
131 struct crypto_tfm
*rx_tfm
; /* CRC32C (Rx) */
132 struct crypto_tfm
*data_rx_tfm
; /* CRC32C (Rx) for data */
135 int senselen
; /* scsi sense length */
137 struct iscsi_tcp_recv in
; /* TCP receive context */
138 struct iscsi_session
*session
; /* parent session */
139 struct list_head item
; /* maintains list of conns */
140 int in_progress
; /* connection state machine */
141 int c_stage
; /* connection state */
142 struct iscsi_mgmt_task
*login_mtask
; /* mtask used for login/text */
143 struct iscsi_mgmt_task
*mtask
; /* xmit mtask in progress */
144 struct iscsi_cmd_task
*ctask
; /* xmit ctask in progress */
145 spinlock_t lock
; /* FIXME: to be removed */
147 /* old values for socket callbacks */
148 void (*old_data_ready
)(struct sock
*, int);
149 void (*old_state_change
)(struct sock
*);
150 void (*old_write_space
)(struct sock
*);
153 struct crypto_tfm
*tx_tfm
; /* CRC32C (Tx) */
154 struct crypto_tfm
*data_tx_tfm
; /* CRC32C (Tx) for data */
155 struct kfifo
*writequeue
; /* write cmds for Data-Outs */
156 struct kfifo
*immqueue
; /* immediate xmit queue */
157 struct kfifo
*mgmtqueue
; /* mgmt (control) xmit queue */
158 struct kfifo
*xmitqueue
; /* data-path cmd queue */
159 struct work_struct xmitwork
; /* per-conn. xmit workqueue */
160 struct semaphore xmitsema
; /* serializes connection xmit,
161 * access to kfifos: *
162 * xmitqueue, writequeue, *
163 * immqueue, mgmtqueue */
164 unsigned long suspend_tx
; /* suspend Tx */
167 wait_queue_head_t ehwait
; /* used in eh_abort() */
168 struct iscsi_tm tmhdr
;
169 struct timer_list tmabort_timer
; /* abort timer */
170 int tmabort_state
; /* see TMABORT_INITIAL, etc.*/
172 /* negotiated params */
173 int max_recv_dlength
;
174 int max_xmit_dlength
;
179 uint64_t txdata_octets
;
180 uint64_t rxdata_octets
;
181 uint32_t scsicmd_pdus_cnt
;
182 uint32_t dataout_pdus_cnt
;
183 uint32_t scsirsp_pdus_cnt
;
184 uint32_t datain_pdus_cnt
;
185 uint32_t r2t_pdus_cnt
;
186 uint32_t tmfcmd_pdus_cnt
;
187 int32_t tmfrsp_pdus_cnt
;
189 /* custom statistics */
190 uint32_t sendpage_failures_cnt
;
191 uint32_t discontiguous_hdr_cnt
;
192 uint32_t eh_abort_cnt
;
195 struct iscsi_session
{
196 /* iSCSI session-wide sequencing */
210 int dataseq_inorder_en
;
216 struct Scsi_Host
*host
;
218 struct iscsi_conn
*leadconn
; /* leading connection */
219 spinlock_t lock
; /* protects session state, *
220 * sequence numbers, *
221 * session resources: *
225 int state
; /* session state */
226 struct list_head item
;
229 int age
; /* counts session re-opens */
231 struct list_head connections
; /* list of connections */
232 int cmds_max
; /* size of cmds array */
233 struct iscsi_cmd_task
**cmds
; /* Original Cmds arr */
234 struct iscsi_queue cmdpool
; /* PDU's pool */
235 int mgmtpool_max
; /* size of mgmt array */
236 struct iscsi_mgmt_task
**mgmt_cmds
; /* Original mgmt arr */
237 struct iscsi_queue mgmtpool
; /* Mgmt PDU's pool */
241 struct scatterlist sg
;
246 struct iscsi_data_task
{
247 struct iscsi_data hdr
; /* PDU */
248 char hdrext
[sizeof(__u32
)]; /* Header-Digest */
249 struct list_head item
; /* data queue item */
250 struct iscsi_buf digestbuf
; /* digest buffer */
251 uint32_t digest
; /* data digest */
253 #define ISCSI_DTASK_DEFAULT_MAX ISCSI_SG_TABLESIZE * PAGE_SIZE / 512
255 struct iscsi_mgmt_task
{
256 struct iscsi_hdr hdr
; /* mgmt. PDU */
257 char hdrext
[sizeof(__u32
)]; /* Header-Digest */
258 char *data
; /* mgmt payload */
259 int xmstate
; /* mgmt xmit progress */
260 int data_count
; /* counts data to be sent */
261 struct iscsi_buf headbuf
; /* header buffer */
262 struct iscsi_buf sendbuf
; /* in progress buffer */
264 uint32_t itt
; /* this ITT */
267 struct iscsi_r2t_info
{
268 __be32 ttt
; /* copied from R2T */
269 __be32 exp_statsn
; /* copied from R2T */
270 uint32_t data_length
; /* copied from R2T */
271 uint32_t data_offset
; /* copied from R2T */
272 struct iscsi_buf headbuf
; /* Data-Out Header Buffer */
273 struct iscsi_buf sendbuf
; /* Data-Out in progress buffer*/
274 int sent
; /* R2T sequence progress */
275 int data_count
; /* DATA-Out payload progress */
276 struct scatterlist
*sg
; /* per-R2T SG list */
278 struct iscsi_data_task
*dtask
; /* which data task */
281 struct iscsi_cmd_task
{
282 struct iscsi_cmd hdr
; /* iSCSI PDU header */
283 char hdrext
[4*sizeof(__u16
)+ /* AHS */
284 sizeof(__u32
)]; /* HeaderDigest */
285 char pad
[ISCSI_PAD_LEN
];
286 int itt
; /* this ITT */
287 int datasn
; /* DataSN */
288 struct iscsi_buf headbuf
; /* header buf (xmit) */
289 struct iscsi_buf sendbuf
; /* in progress buffer*/
291 struct scatterlist
*sg
; /* per-cmd SG list */
292 struct scatterlist
*bad_sg
; /* assert statement */
293 int sg_count
; /* SG's to process */
294 uint32_t unsol_datasn
;
296 int xmstate
; /* xmit xtate machine */
297 int imm_count
; /* imm-data (bytes) */
298 int unsol_count
; /* unsolicited (bytes)*/
299 int r2t_data_count
; /* R2T Data-Out bytes */
300 int data_count
; /* remaining Data-Out */
301 int pad_count
; /* padded bytes */
302 struct scsi_cmnd
*sc
; /* associated SCSI cmd*/
305 struct iscsi_conn
*conn
; /* used connection */
306 struct iscsi_mgmt_task
*mtask
; /* tmf mtask in progr */
308 struct iscsi_r2t_info
*r2t
; /* in progress R2T */
309 struct iscsi_queue r2tpool
;
310 struct kfifo
*r2tqueue
;
311 struct iscsi_r2t_info
**r2ts
;
312 struct list_head dataqueue
; /* Data-Out dataqueue */
314 uint32_t datadigest
; /* for recover digest */
316 uint32_t immdigest
; /* for imm data */
317 struct iscsi_buf immbuf
; /* for imm data digest */
318 struct iscsi_data_task
*dtask
; /* data task in progress*/
319 int digest_offset
; /* for partial buff digest */