1 /*
2 * iSCSI lib definitions
3 *
4 * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
5 * Copyright (C) 2004 - 2006 Mike Christie
6 * Copyright (C) 2004 - 2005 Dmitry Yusupov
7 * Copyright (C) 2004 - 2005 Alex Aizman
8 *
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 by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
22 */
23 #ifndef LIBISCSI_H
24 #define LIBISCSI_H
25
26 #include <linux/types.h>
27 #include <linux/wait.h>
28 #include <linux/mutex.h>
29 #include <linux/timer.h>
30 #include <linux/workqueue.h>
31 #include <scsi/iscsi_proto.h>
32 #include <scsi/iscsi_if.h>
33 #include <scsi/scsi_transport_iscsi.h>
34
35 struct scsi_transport_template;
36 struct scsi_host_template;
37 struct scsi_device;
38 struct Scsi_Host;
39 struct scsi_cmnd;
40 struct socket;
41 struct iscsi_transport;
42 struct iscsi_cls_session;
43 struct iscsi_cls_conn;
44 struct iscsi_session;
45 struct iscsi_nopin;
46 struct device;
47
48 /* #define DEBUG_SCSI */
49 #ifdef DEBUG_SCSI
50 #define debug_scsi(fmt...) printk(KERN_INFO "iscsi: " fmt)
51 #else
52 #define debug_scsi(fmt...)
53 #endif
54
55 #define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
56 #define ISCSI_MGMT_CMDS_MAX 15
57
58 #define ISCSI_DEF_CMD_PER_LUN 32
59 #define ISCSI_MAX_CMD_PER_LUN 128
60
61 /* Task Mgmt states */
62 enum {
63 TMF_INITIAL,
64 TMF_QUEUED,
65 TMF_SUCCESS,
66 TMF_FAILED,
67 TMF_TIMEDOUT,
68 TMF_NOT_FOUND,
69 };
70
71 /* Connection suspend "bit" */
72 #define ISCSI_SUSPEND_BIT 1
73
74 #define ISCSI_ITT_MASK 0x1fff
75 #define ISCSI_TOTAL_CMDS_MAX 4096
76 /* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
77 #define ISCSI_TOTAL_CMDS_MIN 16
78 #define ISCSI_AGE_SHIFT 28
79 #define ISCSI_AGE_MASK 0xf
80
81 #define ISCSI_ADDRESS_BUF_LEN 64
82
83 enum {
84 /* this is the maximum possible storage for AHSs */
85 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
86 sizeof(struct iscsi_rlength_ahdr),
87 ISCSI_DIGEST_SIZE = sizeof(__u32),
88 };
89
90
91 enum {
92 ISCSI_TASK_COMPLETED,
93 ISCSI_TASK_PENDING,
94 ISCSI_TASK_RUNNING,
95 };
96
97 struct iscsi_r2t_info {
98 __be32 ttt; /* copied from R2T */
99 __be32 exp_statsn; /* copied from R2T */
100 uint32_t data_length; /* copied from R2T */
101 uint32_t data_offset; /* copied from R2T */
102 int data_count; /* DATA-Out payload progress */
103 int datasn;
104 /* LLDs should set/update these values */
105 int sent; /* R2T sequence progress */
106 };
107
108 struct iscsi_task {
109 /*
110 * Because LLDs allocate their hdr differently, this is a pointer
111 * and length to that storage. It must be setup at session
112 * creation time.
113 */
114 struct iscsi_hdr *hdr;
115 unsigned short hdr_max;
116 unsigned short hdr_len; /* accumulated size of hdr used */
117 /* copied values in case we need to send tmfs */
118 itt_t hdr_itt;
119 __be32 cmdsn;
120 uint8_t lun[8];
121
122 int itt; /* this ITT */
123
124 unsigned imm_count; /* imm-data (bytes) */
125 /* offset in unsolicited stream (bytes); */
126 struct iscsi_r2t_info unsol_r2t;
127 char *data; /* mgmt payload */
128 unsigned data_count;
129 struct scsi_cmnd *sc; /* associated SCSI cmd*/
130 struct iscsi_conn *conn; /* used connection */
131
132 /* state set/tested under session->lock */
133 int state;
134 atomic_t refcount;
135 struct list_head running; /* running cmd list */
136 void *dd_data; /* driver/transport data */
137 };
138
iscsi_task_has_unsol_data(struct iscsi_task * task)139 static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
140 {
141 return task->unsol_r2t.data_length > task->unsol_r2t.sent;
142 }
143
iscsi_next_hdr(struct iscsi_task * task)144 static inline void* iscsi_next_hdr(struct iscsi_task *task)
145 {
146 return (void*)task->hdr + task->hdr_len;
147 }
148
149 /* Connection's states */
150 enum {
151 ISCSI_CONN_INITIAL_STAGE,
152 ISCSI_CONN_STARTED,
153 ISCSI_CONN_STOPPED,
154 ISCSI_CONN_CLEANUP_WAIT,
155 };
156
157 struct iscsi_conn {
158 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
159 void *dd_data; /* iscsi_transport data */
160 struct iscsi_session *session; /* parent session */
161 /*
162 * conn_stop() flag: stop to recover, stop to terminate
163 */
164 int stop_stage;
165 struct timer_list transport_timer;
166 unsigned long last_recv;
167 unsigned long last_ping;
168 int ping_timeout;
169 int recv_timeout;
170 struct iscsi_task *ping_task;
171
172 /* iSCSI connection-wide sequencing */
173 uint32_t exp_statsn;
174
175 /* control data */
176 int id; /* CID */
177 int c_stage; /* connection state */
178 /*
179 * Preallocated buffer for pdus that have data but do not
180 * originate from scsi-ml. We never have two pdus using the
181 * buffer at the same time. It is only allocated to
182 * the default max recv size because the pdus we support
183 * should always fit in this buffer
184 */
185 char *data;
186 struct iscsi_task *login_task; /* mtask used for login/text */
187 struct iscsi_task *task; /* xmit task in progress */
188
189 /* xmit */
190 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
191 struct list_head mgmt_run_list; /* list of control tasks */
192 struct list_head xmitqueue; /* data-path cmd queue */
193 struct list_head run_list; /* list of cmds in progress */
194 struct list_head requeue; /* tasks needing another run */
195 struct work_struct xmitwork; /* per-conn. xmit workqueue */
196 unsigned long suspend_tx; /* suspend Tx */
197 unsigned long suspend_rx; /* suspend Rx */
198
199 /* abort */
200 wait_queue_head_t ehwait; /* used in eh_abort() */
201 struct iscsi_tm tmhdr;
202 struct timer_list tmf_timer;
203 int tmf_state; /* see TMF_INITIAL, etc.*/
204
205 /* negotiated params */
206 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
207 unsigned max_xmit_dlength; /* target_max_recv_dsl */
208 int hdrdgst_en;
209 int datadgst_en;
210 int ifmarker_en;
211 int ofmarker_en;
212 /* values userspace uses to id a conn */
213 int persistent_port;
214 char *persistent_address;
215 /* remote portal currently connected to */
216 int portal_port;
217 char portal_address[ISCSI_ADDRESS_BUF_LEN];
218
219 /* MIB-statistics */
220 uint64_t txdata_octets;
221 uint64_t rxdata_octets;
222 uint32_t scsicmd_pdus_cnt;
223 uint32_t dataout_pdus_cnt;
224 uint32_t scsirsp_pdus_cnt;
225 uint32_t datain_pdus_cnt;
226 uint32_t r2t_pdus_cnt;
227 uint32_t tmfcmd_pdus_cnt;
228 int32_t tmfrsp_pdus_cnt;
229
230 /* custom statistics */
231 uint32_t eh_abort_cnt;
232 uint32_t fmr_unalign_cnt;
233 };
234
235 struct iscsi_pool {
236 struct kfifo *queue; /* FIFO Queue */
237 void **pool; /* Pool of elements */
238 int max; /* Max number of elements */
239 };
240
241 /* Session's states */
242 enum {
243 ISCSI_STATE_FREE = 1,
244 ISCSI_STATE_LOGGED_IN,
245 ISCSI_STATE_FAILED,
246 ISCSI_STATE_TERMINATE,
247 ISCSI_STATE_IN_RECOVERY,
248 ISCSI_STATE_RECOVERY_FAILED,
249 ISCSI_STATE_LOGGING_OUT,
250 };
251
252 struct iscsi_session {
253 struct iscsi_cls_session *cls_session;
254 /*
255 * Syncs up the scsi eh thread with the iscsi eh thread when sending
256 * task management functions. This must be taken before the session
257 * and recv lock.
258 */
259 struct mutex eh_mutex;
260
261 /* iSCSI session-wide sequencing */
262 uint32_t cmdsn;
263 uint32_t exp_cmdsn;
264 uint32_t max_cmdsn;
265
266 /* This tracks the reqs queued into the initiator */
267 uint32_t queued_cmdsn;
268
269 /* configuration */
270 int abort_timeout;
271 int lu_reset_timeout;
272 int initial_r2t_en;
273 unsigned max_r2t;
274 int imm_data_en;
275 unsigned first_burst;
276 unsigned max_burst;
277 int time2wait;
278 int time2retain;
279 int pdu_inorder_en;
280 int dataseq_inorder_en;
281 int erl;
282 int fast_abort;
283 int tpgt;
284 char *username;
285 char *username_in;
286 char *password;
287 char *password_in;
288 char *targetname;
289 char *ifacename;
290 char *initiatorname;
291 /* control data */
292 struct iscsi_transport *tt;
293 struct Scsi_Host *host;
294 struct iscsi_conn *leadconn; /* leading connection */
295 spinlock_t lock; /* protects session state, *
296 * sequence numbers, *
297 * session resources: *
298 * - cmdpool, *
299 * - mgmtpool, *
300 * - r2tpool */
301 int state; /* session state */
302 int age; /* counts session re-opens */
303
304 int scsi_cmds_max; /* max scsi commands */
305 int cmds_max; /* size of cmds array */
306 struct iscsi_task **cmds; /* Original Cmds arr */
307 struct iscsi_pool cmdpool; /* PDU's pool */
308 };
309
310 enum {
311 ISCSI_HOST_SETUP,
312 ISCSI_HOST_REMOVED,
313 };
314
315 struct iscsi_host {
316 char *initiatorname;
317 /* hw address or netdev iscsi connection is bound to */
318 char *hwaddress;
319 char *netdev;
320 /* local address */
321 int local_port;
322 char local_address[ISCSI_ADDRESS_BUF_LEN];
323
324 wait_queue_head_t session_removal_wq;
325 /* protects sessions and state */
326 spinlock_t lock;
327 int num_sessions;
328 int state;
329 };
330
331 /*
332 * scsi host template
333 */
334 extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
335 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
336 extern int iscsi_eh_target_reset(struct scsi_cmnd *sc);
337 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
338 extern int iscsi_queuecommand(struct scsi_cmnd *sc,
339 void (*done)(struct scsi_cmnd *));
340
341 /*
342 * iSCSI host helpers.
343 */
344 #define iscsi_host_priv(_shost) \
345 (shost_priv(_shost) + sizeof(struct iscsi_host))
346
347 extern int iscsi_host_set_param(struct Scsi_Host *shost,
348 enum iscsi_host_param param, char *buf,
349 int buflen);
350 extern int iscsi_host_get_param(struct Scsi_Host *shost,
351 enum iscsi_host_param param, char *buf);
352 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
353 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
354 int dd_data_size, uint16_t qdepth);
355 extern void iscsi_host_remove(struct Scsi_Host *shost);
356 extern void iscsi_host_free(struct Scsi_Host *shost);
357
358 /*
359 * session management
360 */
361 extern struct iscsi_cls_session *
362 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
363 uint16_t, int, uint32_t, unsigned int);
364 extern void iscsi_session_teardown(struct iscsi_cls_session *);
365 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
366 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
367 enum iscsi_param param, char *buf, int buflen);
368 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
369 enum iscsi_param param, char *buf);
370
371 #define iscsi_session_printk(prefix, _sess, fmt, a...) \
372 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
373
374 /*
375 * connection management
376 */
377 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
378 int, uint32_t);
379 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
380 extern int iscsi_conn_start(struct iscsi_cls_conn *);
381 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
382 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
383 int);
384 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
385 extern void iscsi_session_failure(struct iscsi_cls_session *cls_session,
386 enum iscsi_err err);
387 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
388 enum iscsi_param param, char *buf);
389 extern void iscsi_suspend_tx(struct iscsi_conn *conn);
390
391 #define iscsi_conn_printk(prefix, _c, fmt, a...) \
392 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
393 fmt, ##a)
394
395 /*
396 * pdu and task processing
397 */
398 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
399 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
400 struct iscsi_r2t_info *r2t,
401 struct iscsi_data *hdr);
402 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
403 char *, uint32_t);
404 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
405 char *, int);
406 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
407 char *, int);
408 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
409 extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
410 extern void iscsi_requeue_task(struct iscsi_task *task);
411 extern void iscsi_put_task(struct iscsi_task *task);
412 extern void __iscsi_get_task(struct iscsi_task *task);
413
414 /*
415 * generic helpers
416 */
417 extern void iscsi_pool_free(struct iscsi_pool *);
418 extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
419
420 /*
421 * inline functions to deal with padding.
422 */
423 static inline unsigned int
iscsi_padded(unsigned int len)424 iscsi_padded(unsigned int len)
425 {
426 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
427 }
428
429 static inline unsigned int
iscsi_padding(unsigned int len)430 iscsi_padding(unsigned int len)
431 {
432 len &= (ISCSI_PAD_LEN - 1);
433 if (len)
434 len = ISCSI_PAD_LEN - len;
435 return len;
436 }
437
438 #endif
439