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 <linux/kfifo.h>
32 #include <linux/refcount.h>
33 #include <scsi/iscsi_proto.h>
34 #include <scsi/iscsi_if.h>
35 #include <scsi/scsi_transport_iscsi.h>
36
37 struct scsi_transport_template;
38 struct scsi_host_template;
39 struct scsi_device;
40 struct Scsi_Host;
41 struct scsi_target;
42 struct scsi_cmnd;
43 struct socket;
44 struct iscsi_transport;
45 struct iscsi_cls_session;
46 struct iscsi_cls_conn;
47 struct iscsi_session;
48 struct iscsi_nopin;
49 struct device;
50
51 #define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
52 #define ISCSI_MGMT_CMDS_MAX 15
53
54 #define ISCSI_DEF_CMD_PER_LUN 32
55
56 /* Task Mgmt states */
57 enum {
58 TMF_INITIAL,
59 TMF_QUEUED,
60 TMF_SUCCESS,
61 TMF_FAILED,
62 TMF_TIMEDOUT,
63 TMF_NOT_FOUND,
64 };
65
66 #define ISID_SIZE 6
67
68 /* Connection suspend "bit" */
69 #define ISCSI_SUSPEND_BIT 1
70
71 #define ISCSI_ITT_MASK 0x1fff
72 #define ISCSI_TOTAL_CMDS_MAX 4096
73 /* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
74 #define ISCSI_TOTAL_CMDS_MIN 16
75 #define ISCSI_AGE_SHIFT 28
76 #define ISCSI_AGE_MASK 0xf
77
78 #define ISCSI_ADDRESS_BUF_LEN 64
79
80 enum {
81 /* this is the maximum possible storage for AHSs */
82 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
83 sizeof(struct iscsi_rlength_ahdr),
84 ISCSI_DIGEST_SIZE = sizeof(__u32),
85 };
86
87
88 enum {
89 ISCSI_TASK_FREE,
90 ISCSI_TASK_COMPLETED,
91 ISCSI_TASK_PENDING,
92 ISCSI_TASK_RUNNING,
93 ISCSI_TASK_ABRT_TMF, /* aborted due to TMF */
94 ISCSI_TASK_ABRT_SESS_RECOV, /* aborted due to session recovery */
95 ISCSI_TASK_REQUEUE_SCSIQ, /* qcmd requeueing to scsi-ml */
96 };
97
98 struct iscsi_r2t_info {
99 __be32 ttt; /* copied from R2T */
100 __be32 exp_statsn; /* copied from R2T */
101 uint32_t data_length; /* copied from R2T */
102 uint32_t data_offset; /* copied from R2T */
103 int data_count; /* DATA-Out payload progress */
104 int datasn;
105 /* LLDs should set/update these values */
106 int sent; /* R2T sequence progress */
107 };
108
109 struct iscsi_task {
110 /*
111 * Because LLDs allocate their hdr differently, this is a pointer
112 * and length to that storage. It must be setup at session
113 * creation time.
114 */
115 struct iscsi_hdr *hdr;
116 unsigned short hdr_max;
117 unsigned short hdr_len; /* accumulated size of hdr used */
118 /* copied values in case we need to send tmfs */
119 itt_t hdr_itt;
120 __be32 cmdsn;
121 struct scsi_lun lun;
122
123 int itt; /* this ITT */
124
125 unsigned imm_count; /* imm-data (bytes) */
126 /* offset in unsolicited stream (bytes); */
127 struct iscsi_r2t_info unsol_r2t;
128 char *data; /* mgmt payload */
129 unsigned data_count;
130 struct scsi_cmnd *sc; /* associated SCSI cmd*/
131 struct iscsi_conn *conn; /* used connection */
132
133 /* data processing tracking */
134 unsigned long last_xfer;
135 unsigned long last_timeout;
136 bool have_checked_conn;
137
138 /* T10 protection information */
139 bool protected;
140
141 /* state set/tested under session->lock */
142 int state;
143 refcount_t refcount;
144 struct list_head running; /* running cmd list */
145 void *dd_data; /* driver/transport data */
146 };
147
148 /* invalid scsi_task pointer */
149 #define INVALID_SCSI_TASK (struct iscsi_task *)-1l
150
iscsi_task_has_unsol_data(struct iscsi_task * task)151 static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
152 {
153 return task->unsol_r2t.data_length > task->unsol_r2t.sent;
154 }
155
iscsi_next_hdr(struct iscsi_task * task)156 static inline void* iscsi_next_hdr(struct iscsi_task *task)
157 {
158 return (void*)task->hdr + task->hdr_len;
159 }
160
161 /* Connection's states */
162 enum {
163 ISCSI_CONN_INITIAL_STAGE,
164 ISCSI_CONN_STARTED,
165 ISCSI_CONN_STOPPED,
166 ISCSI_CONN_CLEANUP_WAIT,
167 };
168
169 struct iscsi_conn {
170 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
171 void *dd_data; /* iscsi_transport data */
172 struct iscsi_session *session; /* parent session */
173 /*
174 * conn_stop() flag: stop to recover, stop to terminate
175 */
176 int stop_stage;
177 struct timer_list transport_timer;
178 unsigned long last_recv;
179 unsigned long last_ping;
180 int ping_timeout;
181 int recv_timeout;
182 struct iscsi_task *ping_task;
183
184 /* iSCSI connection-wide sequencing */
185 uint32_t exp_statsn;
186 uint32_t statsn;
187
188 /* control data */
189 int id; /* CID */
190 int c_stage; /* connection state */
191 /*
192 * Preallocated buffer for pdus that have data but do not
193 * originate from scsi-ml. We never have two pdus using the
194 * buffer at the same time. It is only allocated to
195 * the default max recv size because the pdus we support
196 * should always fit in this buffer
197 */
198 char *data;
199 struct iscsi_task *login_task; /* mtask used for login/text */
200 struct iscsi_task *task; /* xmit task in progress */
201
202 /* xmit */
203 spinlock_t taskqueuelock; /* protects the next three lists */
204 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
205 struct list_head cmdqueue; /* data-path cmd queue */
206 struct list_head requeue; /* tasks needing another run */
207 struct work_struct xmitwork; /* per-conn. xmit workqueue */
208 unsigned long suspend_tx; /* suspend Tx */
209 unsigned long suspend_rx; /* suspend Rx */
210
211 /* negotiated params */
212 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
213 unsigned max_xmit_dlength; /* target_max_recv_dsl */
214 int hdrdgst_en;
215 int datadgst_en;
216 int ifmarker_en;
217 int ofmarker_en;
218 /* values userspace uses to id a conn */
219 int persistent_port;
220 char *persistent_address;
221
222 unsigned max_segment_size;
223 unsigned tcp_xmit_wsf;
224 unsigned tcp_recv_wsf;
225 uint16_t keepalive_tmo;
226 uint16_t local_port;
227 uint8_t tcp_timestamp_stat;
228 uint8_t tcp_nagle_disable;
229 uint8_t tcp_wsf_disable;
230 uint8_t tcp_timer_scale;
231 uint8_t tcp_timestamp_en;
232 uint8_t fragment_disable;
233 uint8_t ipv4_tos;
234 uint8_t ipv6_traffic_class;
235 uint8_t ipv6_flow_label;
236 uint8_t is_fw_assigned_ipv6;
237 char *local_ipaddr;
238
239 /* MIB-statistics */
240 uint64_t txdata_octets;
241 uint64_t rxdata_octets;
242 uint32_t scsicmd_pdus_cnt;
243 uint32_t dataout_pdus_cnt;
244 uint32_t scsirsp_pdus_cnt;
245 uint32_t datain_pdus_cnt;
246 uint32_t r2t_pdus_cnt;
247 uint32_t tmfcmd_pdus_cnt;
248 int32_t tmfrsp_pdus_cnt;
249
250 /* custom statistics */
251 uint32_t eh_abort_cnt;
252 uint32_t fmr_unalign_cnt;
253 };
254
255 struct iscsi_pool {
256 struct kfifo queue; /* FIFO Queue */
257 void **pool; /* Pool of elements */
258 int max; /* Max number of elements */
259 };
260
261 /* Session's states */
262 enum {
263 ISCSI_STATE_FREE = 1,
264 ISCSI_STATE_LOGGED_IN,
265 ISCSI_STATE_FAILED,
266 ISCSI_STATE_TERMINATE,
267 ISCSI_STATE_IN_RECOVERY,
268 ISCSI_STATE_RECOVERY_FAILED,
269 ISCSI_STATE_LOGGING_OUT,
270 };
271
272 struct iscsi_session {
273 struct iscsi_cls_session *cls_session;
274 /*
275 * Syncs up the scsi eh thread with the iscsi eh thread when sending
276 * task management functions. This must be taken before the session
277 * and recv lock.
278 */
279 struct mutex eh_mutex;
280 /* abort */
281 wait_queue_head_t ehwait; /* used in eh_abort() */
282 struct iscsi_tm tmhdr;
283 struct timer_list tmf_timer;
284 int tmf_state; /* see TMF_INITIAL, etc.*/
285
286 /* iSCSI session-wide sequencing */
287 uint32_t cmdsn;
288 uint32_t exp_cmdsn;
289 uint32_t max_cmdsn;
290
291 /* This tracks the reqs queued into the initiator */
292 uint32_t queued_cmdsn;
293
294 /* configuration */
295 int abort_timeout;
296 int lu_reset_timeout;
297 int tgt_reset_timeout;
298 int initial_r2t_en;
299 unsigned short max_r2t;
300 int imm_data_en;
301 unsigned first_burst;
302 unsigned max_burst;
303 int time2wait;
304 int time2retain;
305 int pdu_inorder_en;
306 int dataseq_inorder_en;
307 int erl;
308 int fast_abort;
309 int tpgt;
310 char *username;
311 char *username_in;
312 char *password;
313 char *password_in;
314 char *targetname;
315 char *targetalias;
316 char *ifacename;
317 char *initiatorname;
318 char *boot_root;
319 char *boot_nic;
320 char *boot_target;
321 char *portal_type;
322 char *discovery_parent_type;
323 uint16_t discovery_parent_idx;
324 uint16_t def_taskmgmt_tmo;
325 uint16_t tsid;
326 uint8_t auto_snd_tgt_disable;
327 uint8_t discovery_sess;
328 uint8_t chap_auth_en;
329 uint8_t discovery_logout_en;
330 uint8_t bidi_chap_en;
331 uint8_t discovery_auth_optional;
332 uint8_t isid[ISID_SIZE];
333
334 /* control data */
335 struct iscsi_transport *tt;
336 struct Scsi_Host *host;
337 struct iscsi_conn *leadconn; /* leading connection */
338 /* Between the forward and the backward locks exists a strict locking
339 * hierarchy. The mutual exclusion zone protected by the forward lock
340 * can enclose the mutual exclusion zone protected by the backward lock
341 * but not vice versa.
342 */
343 spinlock_t frwd_lock; /* protects session state, *
344 * cmdsn, queued_cmdsn *
345 * session resources: *
346 * - cmdpool kfifo_out , *
347 * - mgmtpool, */
348 spinlock_t back_lock; /* protects cmdsn_exp *
349 * cmdsn_max, *
350 * cmdpool kfifo_in */
351 int state; /* session state */
352 int age; /* counts session re-opens */
353
354 int scsi_cmds_max; /* max scsi commands */
355 int cmds_max; /* size of cmds array */
356 struct iscsi_task **cmds; /* Original Cmds arr */
357 struct iscsi_pool cmdpool; /* PDU's pool */
358 void *dd_data; /* LLD private data */
359 };
360
361 enum {
362 ISCSI_HOST_SETUP,
363 ISCSI_HOST_REMOVED,
364 };
365
366 struct iscsi_host {
367 char *initiatorname;
368 /* hw address or netdev iscsi connection is bound to */
369 char *hwaddress;
370 char *netdev;
371
372 wait_queue_head_t session_removal_wq;
373 /* protects sessions and state */
374 spinlock_t lock;
375 int num_sessions;
376 int state;
377
378 struct workqueue_struct *workq;
379 char workq_name[20];
380 };
381
382 /*
383 * scsi host template
384 */
385 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
386 extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
387 extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
388 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
389 extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc);
390 extern enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc);
391
392 /*
393 * iSCSI host helpers.
394 */
395 #define iscsi_host_priv(_shost) \
396 (shost_priv(_shost) + sizeof(struct iscsi_host))
397
398 extern int iscsi_host_set_param(struct Scsi_Host *shost,
399 enum iscsi_host_param param, char *buf,
400 int buflen);
401 extern int iscsi_host_get_param(struct Scsi_Host *shost,
402 enum iscsi_host_param param, char *buf);
403 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
404 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
405 int dd_data_size,
406 bool xmit_can_sleep);
407 extern void iscsi_host_remove(struct Scsi_Host *shost);
408 extern void iscsi_host_free(struct Scsi_Host *shost);
409 extern int iscsi_target_alloc(struct scsi_target *starget);
410
411 /*
412 * session management
413 */
414 extern struct iscsi_cls_session *
415 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
416 uint16_t, int, int, uint32_t, unsigned int);
417 extern void iscsi_session_teardown(struct iscsi_cls_session *);
418 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
419 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
420 enum iscsi_param param, char *buf, int buflen);
421 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
422 enum iscsi_param param, char *buf);
423
424 #define iscsi_session_printk(prefix, _sess, fmt, a...) \
425 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
426
427 /*
428 * connection management
429 */
430 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
431 int, uint32_t);
432 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
433 extern int iscsi_conn_start(struct iscsi_cls_conn *);
434 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
435 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
436 int);
437 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
438 extern void iscsi_session_failure(struct iscsi_session *session,
439 enum iscsi_err err);
440 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
441 enum iscsi_param param, char *buf);
442 extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
443 enum iscsi_param param, char *buf);
444 extern void iscsi_suspend_tx(struct iscsi_conn *conn);
445 extern void iscsi_suspend_queue(struct iscsi_conn *conn);
446 extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
447
448 #define iscsi_conn_printk(prefix, _c, fmt, a...) \
449 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
450 fmt, ##a)
451
452 /*
453 * pdu and task processing
454 */
455 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
456 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
457 struct iscsi_r2t_info *r2t,
458 struct iscsi_data *hdr);
459 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
460 char *, uint32_t);
461 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
462 char *, int);
463 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
464 char *, int);
465 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
466 extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
467 extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
468 extern void iscsi_requeue_task(struct iscsi_task *task);
469 extern void iscsi_put_task(struct iscsi_task *task);
470 extern void __iscsi_put_task(struct iscsi_task *task);
471 extern void __iscsi_get_task(struct iscsi_task *task);
472 extern void iscsi_complete_scsi_task(struct iscsi_task *task,
473 uint32_t exp_cmdsn, uint32_t max_cmdsn);
474
475 /*
476 * generic helpers
477 */
478 extern void iscsi_pool_free(struct iscsi_pool *);
479 extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
480 extern int iscsi_switch_str_param(char **, char *);
481
482 /*
483 * inline functions to deal with padding.
484 */
485 static inline unsigned int
iscsi_padded(unsigned int len)486 iscsi_padded(unsigned int len)
487 {
488 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
489 }
490
491 static inline unsigned int
iscsi_padding(unsigned int len)492 iscsi_padding(unsigned int len)
493 {
494 len &= (ISCSI_PAD_LEN - 1);
495 if (len)
496 len = ISCSI_PAD_LEN - len;
497 return len;
498 }
499
500 #endif
501