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 <scsi/iscsi_proto.h>
33 #include <scsi/iscsi_if.h>
34 #include <scsi/scsi_transport_iscsi.h>
35
36 struct scsi_transport_template;
37 struct scsi_host_template;
38 struct scsi_device;
39 struct Scsi_Host;
40 struct scsi_target;
41 struct scsi_cmnd;
42 struct socket;
43 struct iscsi_transport;
44 struct iscsi_cls_session;
45 struct iscsi_cls_conn;
46 struct iscsi_session;
47 struct iscsi_nopin;
48 struct device;
49
50 #define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
51 #define ISCSI_MGMT_CMDS_MAX 15
52
53 #define ISCSI_DEF_CMD_PER_LUN 32
54
55 /* Task Mgmt states */
56 enum {
57 TMF_INITIAL,
58 TMF_QUEUED,
59 TMF_SUCCESS,
60 TMF_FAILED,
61 TMF_TIMEDOUT,
62 TMF_NOT_FOUND,
63 };
64
65 /* Connection suspend "bit" */
66 #define ISCSI_SUSPEND_BIT 1
67
68 #define ISCSI_ITT_MASK 0x1fff
69 #define ISCSI_TOTAL_CMDS_MAX 4096
70 /* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
71 #define ISCSI_TOTAL_CMDS_MIN 16
72 #define ISCSI_AGE_SHIFT 28
73 #define ISCSI_AGE_MASK 0xf
74
75 #define ISCSI_ADDRESS_BUF_LEN 64
76
77 enum {
78 /* this is the maximum possible storage for AHSs */
79 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
80 sizeof(struct iscsi_rlength_ahdr),
81 ISCSI_DIGEST_SIZE = sizeof(__u32),
82 };
83
84
85 enum {
86 ISCSI_TASK_FREE,
87 ISCSI_TASK_COMPLETED,
88 ISCSI_TASK_PENDING,
89 ISCSI_TASK_RUNNING,
90 ISCSI_TASK_ABRT_TMF, /* aborted due to TMF */
91 ISCSI_TASK_ABRT_SESS_RECOV, /* aborted due to session recovery */
92 ISCSI_TASK_REQUEUE_SCSIQ, /* qcmd requeueing to scsi-ml */
93 };
94
95 struct iscsi_r2t_info {
96 __be32 ttt; /* copied from R2T */
97 __be32 exp_statsn; /* copied from R2T */
98 uint32_t data_length; /* copied from R2T */
99 uint32_t data_offset; /* copied from R2T */
100 int data_count; /* DATA-Out payload progress */
101 int datasn;
102 /* LLDs should set/update these values */
103 int sent; /* R2T sequence progress */
104 };
105
106 struct iscsi_task {
107 /*
108 * Because LLDs allocate their hdr differently, this is a pointer
109 * and length to that storage. It must be setup at session
110 * creation time.
111 */
112 struct iscsi_hdr *hdr;
113 unsigned short hdr_max;
114 unsigned short hdr_len; /* accumulated size of hdr used */
115 /* copied values in case we need to send tmfs */
116 itt_t hdr_itt;
117 __be32 cmdsn;
118 struct scsi_lun lun;
119
120 int itt; /* this ITT */
121
122 unsigned imm_count; /* imm-data (bytes) */
123 /* offset in unsolicited stream (bytes); */
124 struct iscsi_r2t_info unsol_r2t;
125 char *data; /* mgmt payload */
126 unsigned data_count;
127 struct scsi_cmnd *sc; /* associated SCSI cmd*/
128 struct iscsi_conn *conn; /* used connection */
129
130 /* data processing tracking */
131 unsigned long last_xfer;
132 unsigned long last_timeout;
133 bool have_checked_conn;
134 /* state set/tested under session->lock */
135 int state;
136 atomic_t refcount;
137 struct list_head running; /* running cmd list */
138 void *dd_data; /* driver/transport data */
139 };
140
iscsi_task_has_unsol_data(struct iscsi_task * task)141 static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
142 {
143 return task->unsol_r2t.data_length > task->unsol_r2t.sent;
144 }
145
iscsi_next_hdr(struct iscsi_task * task)146 static inline void* iscsi_next_hdr(struct iscsi_task *task)
147 {
148 return (void*)task->hdr + task->hdr_len;
149 }
150
151 /* Connection's states */
152 enum {
153 ISCSI_CONN_INITIAL_STAGE,
154 ISCSI_CONN_STARTED,
155 ISCSI_CONN_STOPPED,
156 ISCSI_CONN_CLEANUP_WAIT,
157 };
158
159 struct iscsi_conn {
160 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
161 void *dd_data; /* iscsi_transport data */
162 struct iscsi_session *session; /* parent session */
163 /*
164 * conn_stop() flag: stop to recover, stop to terminate
165 */
166 int stop_stage;
167 struct timer_list transport_timer;
168 unsigned long last_recv;
169 unsigned long last_ping;
170 int ping_timeout;
171 int recv_timeout;
172 struct iscsi_task *ping_task;
173
174 /* iSCSI connection-wide sequencing */
175 uint32_t exp_statsn;
176
177 /* control data */
178 int id; /* CID */
179 int c_stage; /* connection state */
180 /*
181 * Preallocated buffer for pdus that have data but do not
182 * originate from scsi-ml. We never have two pdus using the
183 * buffer at the same time. It is only allocated to
184 * the default max recv size because the pdus we support
185 * should always fit in this buffer
186 */
187 char *data;
188 struct iscsi_task *login_task; /* mtask used for login/text */
189 struct iscsi_task *task; /* xmit task in progress */
190
191 /* xmit */
192 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
193 struct list_head cmdqueue; /* data-path cmd queue */
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
216 /* MIB-statistics */
217 uint64_t txdata_octets;
218 uint64_t rxdata_octets;
219 uint32_t scsicmd_pdus_cnt;
220 uint32_t dataout_pdus_cnt;
221 uint32_t scsirsp_pdus_cnt;
222 uint32_t datain_pdus_cnt;
223 uint32_t r2t_pdus_cnt;
224 uint32_t tmfcmd_pdus_cnt;
225 int32_t tmfrsp_pdus_cnt;
226
227 /* custom statistics */
228 uint32_t eh_abort_cnt;
229 uint32_t fmr_unalign_cnt;
230 };
231
232 struct iscsi_pool {
233 struct kfifo queue; /* FIFO Queue */
234 void **pool; /* Pool of elements */
235 int max; /* Max number of elements */
236 };
237
238 /* Session's states */
239 enum {
240 ISCSI_STATE_FREE = 1,
241 ISCSI_STATE_LOGGED_IN,
242 ISCSI_STATE_FAILED,
243 ISCSI_STATE_TERMINATE,
244 ISCSI_STATE_IN_RECOVERY,
245 ISCSI_STATE_RECOVERY_FAILED,
246 ISCSI_STATE_LOGGING_OUT,
247 };
248
249 struct iscsi_session {
250 struct iscsi_cls_session *cls_session;
251 /*
252 * Syncs up the scsi eh thread with the iscsi eh thread when sending
253 * task management functions. This must be taken before the session
254 * and recv lock.
255 */
256 struct mutex eh_mutex;
257
258 /* iSCSI session-wide sequencing */
259 uint32_t cmdsn;
260 uint32_t exp_cmdsn;
261 uint32_t max_cmdsn;
262
263 /* This tracks the reqs queued into the initiator */
264 uint32_t queued_cmdsn;
265
266 /* configuration */
267 int abort_timeout;
268 int lu_reset_timeout;
269 int tgt_reset_timeout;
270 int initial_r2t_en;
271 unsigned short max_r2t;
272 int imm_data_en;
273 unsigned first_burst;
274 unsigned max_burst;
275 int time2wait;
276 int time2retain;
277 int pdu_inorder_en;
278 int dataseq_inorder_en;
279 int erl;
280 int fast_abort;
281 int tpgt;
282 char *username;
283 char *username_in;
284 char *password;
285 char *password_in;
286 char *targetname;
287 char *targetalias;
288 char *ifacename;
289 char *initiatorname;
290 /* control data */
291 struct iscsi_transport *tt;
292 struct Scsi_Host *host;
293 struct iscsi_conn *leadconn; /* leading connection */
294 spinlock_t lock; /* protects session state, *
295 * sequence numbers, *
296 * session resources: *
297 * - cmdpool, *
298 * - mgmtpool, *
299 * - r2tpool */
300 int state; /* session state */
301 int age; /* counts session re-opens */
302
303 int scsi_cmds_max; /* max scsi commands */
304 int cmds_max; /* size of cmds array */
305 struct iscsi_task **cmds; /* Original Cmds arr */
306 struct iscsi_pool cmdpool; /* PDU's pool */
307 void *dd_data; /* LLD private data */
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
321 wait_queue_head_t session_removal_wq;
322 /* protects sessions and state */
323 spinlock_t lock;
324 int num_sessions;
325 int state;
326
327 struct workqueue_struct *workq;
328 char workq_name[20];
329 };
330
331 /*
332 * scsi host template
333 */
334 extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth,
335 int reason);
336 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
337 extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
338 extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
339 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
340 extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc);
341
342 /*
343 * iSCSI host helpers.
344 */
345 #define iscsi_host_priv(_shost) \
346 (shost_priv(_shost) + sizeof(struct iscsi_host))
347
348 extern int iscsi_host_set_param(struct Scsi_Host *shost,
349 enum iscsi_host_param param, char *buf,
350 int buflen);
351 extern int iscsi_host_get_param(struct Scsi_Host *shost,
352 enum iscsi_host_param param, char *buf);
353 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
354 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
355 int dd_data_size,
356 bool xmit_can_sleep);
357 extern void iscsi_host_remove(struct Scsi_Host *shost);
358 extern void iscsi_host_free(struct Scsi_Host *shost);
359 extern int iscsi_target_alloc(struct scsi_target *starget);
360
361 /*
362 * session management
363 */
364 extern struct iscsi_cls_session *
365 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
366 uint16_t, int, int, uint32_t, unsigned int);
367 extern void iscsi_session_teardown(struct iscsi_cls_session *);
368 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
369 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
370 enum iscsi_param param, char *buf, int buflen);
371 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
372 enum iscsi_param param, char *buf);
373
374 #define iscsi_session_printk(prefix, _sess, fmt, a...) \
375 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
376
377 /*
378 * connection management
379 */
380 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
381 int, uint32_t);
382 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
383 extern int iscsi_conn_start(struct iscsi_cls_conn *);
384 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
385 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
386 int);
387 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
388 extern void iscsi_session_failure(struct iscsi_session *session,
389 enum iscsi_err err);
390 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
391 enum iscsi_param param, char *buf);
392 extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
393 enum iscsi_param param, char *buf);
394 extern void iscsi_suspend_tx(struct iscsi_conn *conn);
395 extern void iscsi_suspend_queue(struct iscsi_conn *conn);
396 extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
397
398 #define iscsi_conn_printk(prefix, _c, fmt, a...) \
399 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
400 fmt, ##a)
401
402 /*
403 * pdu and task processing
404 */
405 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
406 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
407 struct iscsi_r2t_info *r2t,
408 struct iscsi_data *hdr);
409 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
410 char *, uint32_t);
411 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
412 char *, int);
413 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
414 char *, int);
415 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
416 extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
417 extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
418 extern void iscsi_requeue_task(struct iscsi_task *task);
419 extern void iscsi_put_task(struct iscsi_task *task);
420 extern void __iscsi_put_task(struct iscsi_task *task);
421 extern void __iscsi_get_task(struct iscsi_task *task);
422 extern void iscsi_complete_scsi_task(struct iscsi_task *task,
423 uint32_t exp_cmdsn, uint32_t max_cmdsn);
424
425 /*
426 * generic helpers
427 */
428 extern void iscsi_pool_free(struct iscsi_pool *);
429 extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
430 extern int iscsi_switch_str_param(char **, char *);
431
432 /*
433 * inline functions to deal with padding.
434 */
435 static inline unsigned int
iscsi_padded(unsigned int len)436 iscsi_padded(unsigned int len)
437 {
438 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
439 }
440
441 static inline unsigned int
iscsi_padding(unsigned int len)442 iscsi_padding(unsigned int len)
443 {
444 len &= (ISCSI_PAD_LEN - 1);
445 if (len)
446 len = ISCSI_PAD_LEN - len;
447 return len;
448 }
449
450 #endif
451