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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
35struct scsi_transport_template;
36struct scsi_host_template;
37struct scsi_device;
38struct Scsi_Host;
39struct scsi_target;
40struct scsi_cmnd;
41struct socket;
42struct iscsi_transport;
43struct iscsi_cls_session;
44struct iscsi_cls_conn;
45struct iscsi_session;
46struct iscsi_nopin;
47struct device;
48
49#define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
50#define ISCSI_MGMT_CMDS_MAX 15
51
52#define ISCSI_DEF_CMD_PER_LUN 32
53
54/* Task Mgmt states */
55enum {
56 TMF_INITIAL,
57 TMF_QUEUED,
58 TMF_SUCCESS,
59 TMF_FAILED,
60 TMF_TIMEDOUT,
61 TMF_NOT_FOUND,
62};
63
64/* Connection suspend "bit" */
65#define ISCSI_SUSPEND_BIT 1
66
67#define ISCSI_ITT_MASK 0x1fff
68#define ISCSI_TOTAL_CMDS_MAX 4096
69/* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
70#define ISCSI_TOTAL_CMDS_MIN 16
71#define ISCSI_AGE_SHIFT 28
72#define ISCSI_AGE_MASK 0xf
73
74#define ISCSI_ADDRESS_BUF_LEN 64
75
76enum {
77 /* this is the maximum possible storage for AHSs */
78 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
79 sizeof(struct iscsi_rlength_ahdr),
80 ISCSI_DIGEST_SIZE = sizeof(__u32),
81};
82
83
84enum {
85 ISCSI_TASK_FREE,
86 ISCSI_TASK_COMPLETED,
87 ISCSI_TASK_PENDING,
88 ISCSI_TASK_RUNNING,
89 ISCSI_TASK_ABRT_TMF, /* aborted due to TMF */
90 ISCSI_TASK_ABRT_SESS_RECOV, /* aborted due to session recovery */
91};
92
93struct iscsi_r2t_info {
94 __be32 ttt; /* copied from R2T */
95 __be32 exp_statsn; /* copied from R2T */
96 uint32_t data_length; /* copied from R2T */
97 uint32_t data_offset; /* copied from R2T */
98 int data_count; /* DATA-Out payload progress */
99 int datasn;
100 /* LLDs should set/update these values */
101 int sent; /* R2T sequence progress */
102};
103
104struct iscsi_task {
105 /*
106 * Because LLDs allocate their hdr differently, this is a pointer
107 * and length to that storage. It must be setup at session
108 * creation time.
109 */
110 struct iscsi_hdr *hdr;
111 unsigned short hdr_max;
112 unsigned short hdr_len; /* accumulated size of hdr used */
113 /* copied values in case we need to send tmfs */
114 itt_t hdr_itt;
115 __be32 cmdsn;
116 uint8_t lun[8];
117
118 int itt; /* this ITT */
119
120 unsigned imm_count; /* imm-data (bytes) */
121 /* offset in unsolicited stream (bytes); */
122 struct iscsi_r2t_info unsol_r2t;
123 char *data; /* mgmt payload */
124 unsigned data_count;
125 struct scsi_cmnd *sc; /* associated SCSI cmd*/
126 struct iscsi_conn *conn; /* used connection */
127
128 /* data processing tracking */
129 unsigned long last_xfer;
130 unsigned long last_timeout;
131 bool have_checked_conn;
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
139static 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
144static inline void* iscsi_next_hdr(struct iscsi_task *task)
145{
146 return (void*)task->hdr + task->hdr_len;
147}
148
149/* Connection's states */
150enum {
151 ISCSI_CONN_INITIAL_STAGE,
152 ISCSI_CONN_STARTED,
153 ISCSI_CONN_STOPPED,
154 ISCSI_CONN_CLEANUP_WAIT,
155};
156
157struct 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 cmdqueue; /* data-path cmd queue */
192 struct list_head requeue; /* tasks needing another run */
193 struct work_struct xmitwork; /* per-conn. xmit workqueue */
194 unsigned long suspend_tx; /* suspend Tx */
195 unsigned long suspend_rx; /* suspend Rx */
196
197 /* abort */
198 wait_queue_head_t ehwait; /* used in eh_abort() */
199 struct iscsi_tm tmhdr;
200 struct timer_list tmf_timer;
201 int tmf_state; /* see TMF_INITIAL, etc.*/
202
203 /* negotiated params */
204 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
205 unsigned max_xmit_dlength; /* target_max_recv_dsl */
206 int hdrdgst_en;
207 int datadgst_en;
208 int ifmarker_en;
209 int ofmarker_en;
210 /* values userspace uses to id a conn */
211 int persistent_port;
212 char *persistent_address;
213 /* remote portal currently connected to */
214 int portal_port;
215 char portal_address[ISCSI_ADDRESS_BUF_LEN];
216
217 /* MIB-statistics */
218 uint64_t txdata_octets;
219 uint64_t rxdata_octets;
220 uint32_t scsicmd_pdus_cnt;
221 uint32_t dataout_pdus_cnt;
222 uint32_t scsirsp_pdus_cnt;
223 uint32_t datain_pdus_cnt;
224 uint32_t r2t_pdus_cnt;
225 uint32_t tmfcmd_pdus_cnt;
226 int32_t tmfrsp_pdus_cnt;
227
228 /* custom statistics */
229 uint32_t eh_abort_cnt;
230 uint32_t fmr_unalign_cnt;
231};
232
233struct iscsi_pool {
234 struct kfifo *queue; /* FIFO Queue */
235 void **pool; /* Pool of elements */
236 int max; /* Max number of elements */
237};
238
239/* Session's states */
240enum {
241 ISCSI_STATE_FREE = 1,
242 ISCSI_STATE_LOGGED_IN,
243 ISCSI_STATE_FAILED,
244 ISCSI_STATE_TERMINATE,
245 ISCSI_STATE_IN_RECOVERY,
246 ISCSI_STATE_RECOVERY_FAILED,
247 ISCSI_STATE_LOGGING_OUT,
248};
249
250struct iscsi_session {
251 struct iscsi_cls_session *cls_session;
252 /*
253 * Syncs up the scsi eh thread with the iscsi eh thread when sending
254 * task management functions. This must be taken before the session
255 * and recv lock.
256 */
257 struct mutex eh_mutex;
258
259 /* iSCSI session-wide sequencing */
260 uint32_t cmdsn;
261 uint32_t exp_cmdsn;
262 uint32_t max_cmdsn;
263
264 /* This tracks the reqs queued into the initiator */
265 uint32_t queued_cmdsn;
266
267 /* configuration */
268 int abort_timeout;
269 int lu_reset_timeout;
270 int initial_r2t_en;
271 unsigned 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 *ifacename;
288 char *initiatorname;
289 /* control data */
290 struct iscsi_transport *tt;
291 struct Scsi_Host *host;
292 struct iscsi_conn *leadconn; /* leading connection */
293 spinlock_t lock; /* protects session state, *
294 * sequence numbers, *
295 * session resources: *
296 * - cmdpool, *
297 * - mgmtpool, *
298 * - r2tpool */
299 int state; /* session state */
300 int age; /* counts session re-opens */
301
302 int scsi_cmds_max; /* max scsi commands */
303 int cmds_max; /* size of cmds array */
304 struct iscsi_task **cmds; /* Original Cmds arr */
305 struct iscsi_pool cmdpool; /* PDU's pool */
306};
307
308enum {
309 ISCSI_HOST_SETUP,
310 ISCSI_HOST_REMOVED,
311};
312
313struct iscsi_host {
314 char *initiatorname;
315 /* hw address or netdev iscsi connection is bound to */
316 char *hwaddress;
317 char *netdev;
318 /* local address */
319 int local_port;
320 char local_address[ISCSI_ADDRESS_BUF_LEN];
321
322 wait_queue_head_t session_removal_wq;
323 /* protects sessions and state */
324 spinlock_t lock;
325 int num_sessions;
326 int state;
327
328 struct workqueue_struct *workq;
329 char workq_name[20];
330};
331
332/*
333 * scsi host template
334 */
335extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
336extern int iscsi_eh_abort(struct scsi_cmnd *sc);
337extern int iscsi_eh_target_reset(struct scsi_cmnd *sc);
338extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
339extern int iscsi_queuecommand(struct scsi_cmnd *sc,
340 void (*done)(struct scsi_cmnd *));
341
342/*
343 * iSCSI host helpers.
344 */
345#define iscsi_host_priv(_shost) \
346 (shost_priv(_shost) + sizeof(struct iscsi_host))
347
348extern int iscsi_host_set_param(struct Scsi_Host *shost,
349 enum iscsi_host_param param, char *buf,
350 int buflen);
351extern int iscsi_host_get_param(struct Scsi_Host *shost,
352 enum iscsi_host_param param, char *buf);
353extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
354extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
355 int dd_data_size,
356 bool xmit_can_sleep);
357extern void iscsi_host_remove(struct Scsi_Host *shost);
358extern void iscsi_host_free(struct Scsi_Host *shost);
359extern int iscsi_target_alloc(struct scsi_target *starget);
360
361/*
362 * session management
363 */
364extern struct iscsi_cls_session *
365iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
366 uint16_t, int, uint32_t, unsigned int);
367extern void iscsi_session_teardown(struct iscsi_cls_session *);
368extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
369extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
370 enum iscsi_param param, char *buf, int buflen);
371extern 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 */
380extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
381 int, uint32_t);
382extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
383extern int iscsi_conn_start(struct iscsi_cls_conn *);
384extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
385extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
386 int);
387extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
388extern void iscsi_session_failure(struct iscsi_session *session,
389 enum iscsi_err err);
390extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
391 enum iscsi_param param, char *buf);
392extern void iscsi_suspend_tx(struct iscsi_conn *conn);
393extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
394
395#define iscsi_conn_printk(prefix, _c, fmt, a...) \
396 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
397 fmt, ##a)
398
399/*
400 * pdu and task processing
401 */
402extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
403extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
404 struct iscsi_r2t_info *r2t,
405 struct iscsi_data *hdr);
406extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
407 char *, uint32_t);
408extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
409 char *, int);
410extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
411 char *, int);
412extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
413extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
414extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
415extern void iscsi_requeue_task(struct iscsi_task *task);
416extern void iscsi_put_task(struct iscsi_task *task);
417extern void __iscsi_get_task(struct iscsi_task *task);
418
419/*
420 * generic helpers
421 */
422extern void iscsi_pool_free(struct iscsi_pool *);
423extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
424
425/*
426 * inline functions to deal with padding.
427 */
428static inline unsigned int
429iscsi_padded(unsigned int len)
430{
431 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
432}
433
434static inline unsigned int
435iscsi_padding(unsigned int len)
436{
437 len &= (ISCSI_PAD_LEN - 1);
438 if (len)
439 len = ISCSI_PAD_LEN - len;
440 return len;
441}
442
443#endif