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
37struct scsi_transport_template;
38struct scsi_host_template;
39struct scsi_device;
40struct Scsi_Host;
41struct scsi_target;
42struct scsi_cmnd;
43struct socket;
44struct iscsi_transport;
45struct iscsi_cls_session;
46struct iscsi_cls_conn;
47struct iscsi_session;
48struct iscsi_nopin;
49struct 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 */
57enum {
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
80enum {
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
88enum {
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
98struct 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
109struct 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
148static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
149{
150 return task->unsol_r2t.data_length > task->unsol_r2t.sent;
151}
152
153static inline void* iscsi_next_hdr(struct iscsi_task *task)
154{
155 return (void*)task->hdr + task->hdr_len;
156}
157
158/* Connection's states */
159enum {
160 ISCSI_CONN_INITIAL_STAGE,
161 ISCSI_CONN_STARTED,
162 ISCSI_CONN_STOPPED,
163 ISCSI_CONN_CLEANUP_WAIT,
164};
165
166struct iscsi_conn {
167 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
168 void *dd_data; /* iscsi_transport data */
169 struct iscsi_session *session; /* parent session */
170 /*
171 * conn_stop() flag: stop to recover, stop to terminate
172 */
173 int stop_stage;
174 struct timer_list transport_timer;
175 unsigned long last_recv;
176 unsigned long last_ping;
177 int ping_timeout;
178 int recv_timeout;
179 struct iscsi_task *ping_task;
180
181 /* iSCSI connection-wide sequencing */
182 uint32_t exp_statsn;
183 uint32_t statsn;
184
185 /* control data */
186 int id; /* CID */
187 int c_stage; /* connection state */
188 /*
189 * Preallocated buffer for pdus that have data but do not
190 * originate from scsi-ml. We never have two pdus using the
191 * buffer at the same time. It is only allocated to
192 * the default max recv size because the pdus we support
193 * should always fit in this buffer
194 */
195 char *data;
196 struct iscsi_task *login_task; /* mtask used for login/text */
197 struct iscsi_task *task; /* xmit task in progress */
198
199 /* xmit */
200 spinlock_t taskqueuelock; /* protects the next three lists */
201 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
202 struct list_head cmdqueue; /* data-path cmd queue */
203 struct list_head requeue; /* tasks needing another run */
204 struct work_struct xmitwork; /* per-conn. xmit workqueue */
205 unsigned long suspend_tx; /* suspend Tx */
206 unsigned long suspend_rx; /* suspend Rx */
207
208 /* abort */
209 wait_queue_head_t ehwait; /* used in eh_abort() */
210 struct iscsi_tm tmhdr;
211 struct timer_list tmf_timer;
212 int tmf_state; /* see TMF_INITIAL, etc.*/
213
214 /* negotiated params */
215 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
216 unsigned max_xmit_dlength; /* target_max_recv_dsl */
217 int hdrdgst_en;
218 int datadgst_en;
219 int ifmarker_en;
220 int ofmarker_en;
221 /* values userspace uses to id a conn */
222 int persistent_port;
223 char *persistent_address;
224
225 unsigned max_segment_size;
226 unsigned tcp_xmit_wsf;
227 unsigned tcp_recv_wsf;
228 uint16_t keepalive_tmo;
229 uint16_t local_port;
230 uint8_t tcp_timestamp_stat;
231 uint8_t tcp_nagle_disable;
232 uint8_t tcp_wsf_disable;
233 uint8_t tcp_timer_scale;
234 uint8_t tcp_timestamp_en;
235 uint8_t fragment_disable;
236 uint8_t ipv4_tos;
237 uint8_t ipv6_traffic_class;
238 uint8_t ipv6_flow_label;
239 uint8_t is_fw_assigned_ipv6;
240 char *local_ipaddr;
241
242 /* MIB-statistics */
243 uint64_t txdata_octets;
244 uint64_t rxdata_octets;
245 uint32_t scsicmd_pdus_cnt;
246 uint32_t dataout_pdus_cnt;
247 uint32_t scsirsp_pdus_cnt;
248 uint32_t datain_pdus_cnt;
249 uint32_t r2t_pdus_cnt;
250 uint32_t tmfcmd_pdus_cnt;
251 int32_t tmfrsp_pdus_cnt;
252
253 /* custom statistics */
254 uint32_t eh_abort_cnt;
255 uint32_t fmr_unalign_cnt;
256};
257
258struct iscsi_pool {
259 struct kfifo queue; /* FIFO Queue */
260 void **pool; /* Pool of elements */
261 int max; /* Max number of elements */
262};
263
264/* Session's states */
265enum {
266 ISCSI_STATE_FREE = 1,
267 ISCSI_STATE_LOGGED_IN,
268 ISCSI_STATE_FAILED,
269 ISCSI_STATE_TERMINATE,
270 ISCSI_STATE_IN_RECOVERY,
271 ISCSI_STATE_RECOVERY_FAILED,
272 ISCSI_STATE_LOGGING_OUT,
273};
274
275struct iscsi_session {
276 struct iscsi_cls_session *cls_session;
277 /*
278 * Syncs up the scsi eh thread with the iscsi eh thread when sending
279 * task management functions. This must be taken before the session
280 * and recv lock.
281 */
282 struct mutex eh_mutex;
283
284 /* iSCSI session-wide sequencing */
285 uint32_t cmdsn;
286 uint32_t exp_cmdsn;
287 uint32_t max_cmdsn;
288
289 /* This tracks the reqs queued into the initiator */
290 uint32_t queued_cmdsn;
291
292 /* configuration */
293 int abort_timeout;
294 int lu_reset_timeout;
295 int tgt_reset_timeout;
296 int initial_r2t_en;
297 unsigned short max_r2t;
298 int imm_data_en;
299 unsigned first_burst;
300 unsigned max_burst;
301 int time2wait;
302 int time2retain;
303 int pdu_inorder_en;
304 int dataseq_inorder_en;
305 int erl;
306 int fast_abort;
307 int tpgt;
308 char *username;
309 char *username_in;
310 char *password;
311 char *password_in;
312 char *targetname;
313 char *targetalias;
314 char *ifacename;
315 char *initiatorname;
316 char *boot_root;
317 char *boot_nic;
318 char *boot_target;
319 char *portal_type;
320 char *discovery_parent_type;
321 uint16_t discovery_parent_idx;
322 uint16_t def_taskmgmt_tmo;
323 uint16_t tsid;
324 uint8_t auto_snd_tgt_disable;
325 uint8_t discovery_sess;
326 uint8_t chap_auth_en;
327 uint8_t discovery_logout_en;
328 uint8_t bidi_chap_en;
329 uint8_t discovery_auth_optional;
330 uint8_t isid[ISID_SIZE];
331
332 /* control data */
333 struct iscsi_transport *tt;
334 struct Scsi_Host *host;
335 struct iscsi_conn *leadconn; /* leading connection */
336 /* Between the forward and the backward locks exists a strict locking
337 * hierarchy. The mutual exclusion zone protected by the forward lock
338 * can enclose the mutual exclusion zone protected by the backward lock
339 * but not vice versa.
340 */
341 spinlock_t frwd_lock; /* protects session state, *
342 * cmdsn, queued_cmdsn *
343 * session resources: *
344 * - cmdpool kfifo_out , *
345 * - mgmtpool, */
346 spinlock_t back_lock; /* protects cmdsn_exp *
347 * cmdsn_max, *
348 * cmdpool kfifo_in */
349 int state; /* session state */
350 int age; /* counts session re-opens */
351
352 int scsi_cmds_max; /* max scsi commands */
353 int cmds_max; /* size of cmds array */
354 struct iscsi_task **cmds; /* Original Cmds arr */
355 struct iscsi_pool cmdpool; /* PDU's pool */
356 void *dd_data; /* LLD private data */
357};
358
359enum {
360 ISCSI_HOST_SETUP,
361 ISCSI_HOST_REMOVED,
362};
363
364struct iscsi_host {
365 char *initiatorname;
366 /* hw address or netdev iscsi connection is bound to */
367 char *hwaddress;
368 char *netdev;
369
370 wait_queue_head_t session_removal_wq;
371 /* protects sessions and state */
372 spinlock_t lock;
373 int num_sessions;
374 int state;
375
376 struct workqueue_struct *workq;
377 char workq_name[20];
378};
379
380/*
381 * scsi host template
382 */
383extern int iscsi_eh_abort(struct scsi_cmnd *sc);
384extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
385extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
386extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
387extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc);
388extern enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc);
389
390/*
391 * iSCSI host helpers.
392 */
393#define iscsi_host_priv(_shost) \
394 (shost_priv(_shost) + sizeof(struct iscsi_host))
395
396extern int iscsi_host_set_param(struct Scsi_Host *shost,
397 enum iscsi_host_param param, char *buf,
398 int buflen);
399extern int iscsi_host_get_param(struct Scsi_Host *shost,
400 enum iscsi_host_param param, char *buf);
401extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
402extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
403 int dd_data_size,
404 bool xmit_can_sleep);
405extern void iscsi_host_remove(struct Scsi_Host *shost);
406extern void iscsi_host_free(struct Scsi_Host *shost);
407extern int iscsi_target_alloc(struct scsi_target *starget);
408
409/*
410 * session management
411 */
412extern struct iscsi_cls_session *
413iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
414 uint16_t, int, int, uint32_t, unsigned int);
415extern void iscsi_session_teardown(struct iscsi_cls_session *);
416extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
417extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
418 enum iscsi_param param, char *buf, int buflen);
419extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
420 enum iscsi_param param, char *buf);
421
422#define iscsi_session_printk(prefix, _sess, fmt, a...) \
423 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
424
425/*
426 * connection management
427 */
428extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
429 int, uint32_t);
430extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
431extern int iscsi_conn_start(struct iscsi_cls_conn *);
432extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
433extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
434 int);
435extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
436extern void iscsi_session_failure(struct iscsi_session *session,
437 enum iscsi_err err);
438extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
439 enum iscsi_param param, char *buf);
440extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
441 enum iscsi_param param, char *buf);
442extern void iscsi_suspend_tx(struct iscsi_conn *conn);
443extern void iscsi_suspend_queue(struct iscsi_conn *conn);
444extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
445
446#define iscsi_conn_printk(prefix, _c, fmt, a...) \
447 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
448 fmt, ##a)
449
450/*
451 * pdu and task processing
452 */
453extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
454extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
455 struct iscsi_r2t_info *r2t,
456 struct iscsi_data *hdr);
457extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
458 char *, uint32_t);
459extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
460 char *, int);
461extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
462 char *, int);
463extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
464extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
465extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
466extern void iscsi_requeue_task(struct iscsi_task *task);
467extern void iscsi_put_task(struct iscsi_task *task);
468extern void __iscsi_put_task(struct iscsi_task *task);
469extern void __iscsi_get_task(struct iscsi_task *task);
470extern void iscsi_complete_scsi_task(struct iscsi_task *task,
471 uint32_t exp_cmdsn, uint32_t max_cmdsn);
472
473/*
474 * generic helpers
475 */
476extern void iscsi_pool_free(struct iscsi_pool *);
477extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
478extern int iscsi_switch_str_param(char **, char *);
479
480/*
481 * inline functions to deal with padding.
482 */
483static inline unsigned int
484iscsi_padded(unsigned int len)
485{
486 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
487}
488
489static inline unsigned int
490iscsi_padding(unsigned int len)
491{
492 len &= (ISCSI_PAD_LEN - 1);
493 if (len)
494 len = ISCSI_PAD_LEN - len;
495 return len;
496}
497
498#endif
499