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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 <linux/kfifo.h>
32#include <scsi/iscsi_proto.h>
33#include <scsi/iscsi_if.h>
34#include <scsi/scsi_transport_iscsi.h>
35
36struct scsi_transport_template;
37struct scsi_host_template;
38struct scsi_device;
39struct Scsi_Host;
40struct scsi_target;
41struct scsi_cmnd;
42struct socket;
43struct iscsi_transport;
44struct iscsi_cls_session;
45struct iscsi_cls_conn;
46struct iscsi_session;
47struct iscsi_nopin;
48struct 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 */
56enum {
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
77enum {
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
85enum {
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};
93
94struct iscsi_r2t_info {
95 __be32 ttt; /* copied from R2T */
96 __be32 exp_statsn; /* copied from R2T */
97 uint32_t data_length; /* copied from R2T */
98 uint32_t data_offset; /* copied from R2T */
99 int data_count; /* DATA-Out payload progress */
100 int datasn;
101 /* LLDs should set/update these values */
102 int sent; /* R2T sequence progress */
103};
104
105struct iscsi_task {
106 /*
107 * Because LLDs allocate their hdr differently, this is a pointer
108 * and length to that storage. It must be setup at session
109 * creation time.
110 */
111 struct iscsi_hdr *hdr;
112 unsigned short hdr_max;
113 unsigned short hdr_len; /* accumulated size of hdr used */
114 /* copied values in case we need to send tmfs */
115 itt_t hdr_itt;
116 __be32 cmdsn;
117 uint8_t lun[8];
118
119 int itt; /* this ITT */
120
121 unsigned imm_count; /* imm-data (bytes) */
122 /* offset in unsolicited stream (bytes); */
123 struct iscsi_r2t_info unsol_r2t;
124 char *data; /* mgmt payload */
125 unsigned data_count;
126 struct scsi_cmnd *sc; /* associated SCSI cmd*/
127 struct iscsi_conn *conn; /* used connection */
128
129 /* data processing tracking */
130 unsigned long last_xfer;
131 unsigned long last_timeout;
132 bool have_checked_conn;
133 /* state set/tested under session->lock */
134 int state;
135 atomic_t refcount;
136 struct list_head running; /* running cmd list */
137 void *dd_data; /* driver/transport data */
138};
139
140static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
141{
142 return task->unsol_r2t.data_length > task->unsol_r2t.sent;
143}
144
145static inline void* iscsi_next_hdr(struct iscsi_task *task)
146{
147 return (void*)task->hdr + task->hdr_len;
148}
149
150/* Connection's states */
151enum {
152 ISCSI_CONN_INITIAL_STAGE,
153 ISCSI_CONN_STARTED,
154 ISCSI_CONN_STOPPED,
155 ISCSI_CONN_CLEANUP_WAIT,
156};
157
158struct iscsi_conn {
159 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
160 void *dd_data; /* iscsi_transport data */
161 struct iscsi_session *session; /* parent session */
162 /*
163 * conn_stop() flag: stop to recover, stop to terminate
164 */
165 int stop_stage;
166 struct timer_list transport_timer;
167 unsigned long last_recv;
168 unsigned long last_ping;
169 int ping_timeout;
170 int recv_timeout;
171 struct iscsi_task *ping_task;
172
173 /* iSCSI connection-wide sequencing */
174 uint32_t exp_statsn;
175
176 /* control data */
177 int id; /* CID */
178 int c_stage; /* connection state */
179 /*
180 * Preallocated buffer for pdus that have data but do not
181 * originate from scsi-ml. We never have two pdus using the
182 * buffer at the same time. It is only allocated to
183 * the default max recv size because the pdus we support
184 * should always fit in this buffer
185 */
186 char *data;
187 struct iscsi_task *login_task; /* mtask used for login/text */
188 struct iscsi_task *task; /* xmit task in progress */
189
190 /* xmit */
191 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
192 struct list_head cmdqueue; /* data-path cmd queue */
193 struct list_head requeue; /* tasks needing another run */
194 struct work_struct xmitwork; /* per-conn. xmit workqueue */
195 unsigned long suspend_tx; /* suspend Tx */
196 unsigned long suspend_rx; /* suspend Rx */
197
198 /* abort */
199 wait_queue_head_t ehwait; /* used in eh_abort() */
200 struct iscsi_tm tmhdr;
201 struct timer_list tmf_timer;
202 int tmf_state; /* see TMF_INITIAL, etc.*/
203
204 /* negotiated params */
205 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
206 unsigned max_xmit_dlength; /* target_max_recv_dsl */
207 int hdrdgst_en;
208 int datadgst_en;
209 int ifmarker_en;
210 int ofmarker_en;
211 /* values userspace uses to id a conn */
212 int persistent_port;
213 char *persistent_address;
214 /* remote portal currently connected to */
215 int portal_port;
216 char portal_address[ISCSI_ADDRESS_BUF_LEN];
217
218 /* MIB-statistics */
219 uint64_t txdata_octets;
220 uint64_t rxdata_octets;
221 uint32_t scsicmd_pdus_cnt;
222 uint32_t dataout_pdus_cnt;
223 uint32_t scsirsp_pdus_cnt;
224 uint32_t datain_pdus_cnt;
225 uint32_t r2t_pdus_cnt;
226 uint32_t tmfcmd_pdus_cnt;
227 int32_t tmfrsp_pdus_cnt;
228
229 /* custom statistics */
230 uint32_t eh_abort_cnt;
231 uint32_t fmr_unalign_cnt;
232};
233
234struct iscsi_pool {
235 struct kfifo queue; /* FIFO Queue */
236 void **pool; /* Pool of elements */
237 int max; /* Max number of elements */
238};
239
240/* Session's states */
241enum {
242 ISCSI_STATE_FREE = 1,
243 ISCSI_STATE_LOGGED_IN,
244 ISCSI_STATE_FAILED,
245 ISCSI_STATE_TERMINATE,
246 ISCSI_STATE_IN_RECOVERY,
247 ISCSI_STATE_RECOVERY_FAILED,
248 ISCSI_STATE_LOGGING_OUT,
249};
250
251struct iscsi_session {
252 struct iscsi_cls_session *cls_session;
253 /*
254 * Syncs up the scsi eh thread with the iscsi eh thread when sending
255 * task management functions. This must be taken before the session
256 * and recv lock.
257 */
258 struct mutex eh_mutex;
259
260 /* iSCSI session-wide sequencing */
261 uint32_t cmdsn;
262 uint32_t exp_cmdsn;
263 uint32_t max_cmdsn;
264
265 /* This tracks the reqs queued into the initiator */
266 uint32_t queued_cmdsn;
267
268 /* configuration */
269 int abort_timeout;
270 int lu_reset_timeout;
271 int tgt_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 void *dd_data; /* LLD private data */
309};
310
311enum {
312 ISCSI_HOST_SETUP,
313 ISCSI_HOST_REMOVED,
314};
315
316struct iscsi_host {
317 char *initiatorname;
318 /* hw address or netdev iscsi connection is bound to */
319 char *hwaddress;
320 char *netdev;
321 /* local address */
322 int local_port;
323 char local_address[ISCSI_ADDRESS_BUF_LEN];
324
325 wait_queue_head_t session_removal_wq;
326 /* protects sessions and state */
327 spinlock_t lock;
328 int num_sessions;
329 int state;
330
331 struct workqueue_struct *workq;
332 char workq_name[20];
333};
334
335/*
336 * scsi host template
337 */
338extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth,
339 int reason);
340extern int iscsi_eh_abort(struct scsi_cmnd *sc);
341extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
342extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
343extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
344extern int iscsi_queuecommand(struct scsi_cmnd *sc,
345 void (*done)(struct scsi_cmnd *));
346
347/*
348 * iSCSI host helpers.
349 */
350#define iscsi_host_priv(_shost) \
351 (shost_priv(_shost) + sizeof(struct iscsi_host))
352
353extern int iscsi_host_set_param(struct Scsi_Host *shost,
354 enum iscsi_host_param param, char *buf,
355 int buflen);
356extern int iscsi_host_get_param(struct Scsi_Host *shost,
357 enum iscsi_host_param param, char *buf);
358extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
359extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
360 int dd_data_size,
361 bool xmit_can_sleep);
362extern void iscsi_host_remove(struct Scsi_Host *shost);
363extern void iscsi_host_free(struct Scsi_Host *shost);
364extern int iscsi_target_alloc(struct scsi_target *starget);
365
366/*
367 * session management
368 */
369extern struct iscsi_cls_session *
370iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
371 uint16_t, int, int, uint32_t, unsigned int);
372extern void iscsi_session_teardown(struct iscsi_cls_session *);
373extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
374extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
375 enum iscsi_param param, char *buf, int buflen);
376extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
377 enum iscsi_param param, char *buf);
378
379#define iscsi_session_printk(prefix, _sess, fmt, a...) \
380 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
381
382/*
383 * connection management
384 */
385extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
386 int, uint32_t);
387extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
388extern int iscsi_conn_start(struct iscsi_cls_conn *);
389extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
390extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
391 int);
392extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
393extern void iscsi_session_failure(struct iscsi_session *session,
394 enum iscsi_err err);
395extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
396 enum iscsi_param param, char *buf);
397extern void iscsi_suspend_tx(struct iscsi_conn *conn);
398extern void iscsi_suspend_queue(struct iscsi_conn *conn);
399extern void iscsi_conn_queue_work(struct iscsi_conn *conn);
400
401#define iscsi_conn_printk(prefix, _c, fmt, a...) \
402 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
403 fmt, ##a)
404
405/*
406 * pdu and task processing
407 */
408extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
409extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
410 struct iscsi_r2t_info *r2t,
411 struct iscsi_data *hdr);
412extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
413 char *, uint32_t);
414extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
415 char *, int);
416extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
417 char *, int);
418extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
419extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
420extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
421extern void iscsi_requeue_task(struct iscsi_task *task);
422extern void iscsi_put_task(struct iscsi_task *task);
423extern void __iscsi_get_task(struct iscsi_task *task);
424extern void iscsi_complete_scsi_task(struct iscsi_task *task,
425 uint32_t exp_cmdsn, uint32_t max_cmdsn);
426
427/*
428 * generic helpers
429 */
430extern void iscsi_pool_free(struct iscsi_pool *);
431extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
432
433/*
434 * inline functions to deal with padding.
435 */
436static inline unsigned int
437iscsi_padded(unsigned int len)
438{
439 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
440}
441
442static inline unsigned int
443iscsi_padding(unsigned int len)
444{
445 len &= (ISCSI_PAD_LEN - 1);
446 if (len)
447 len = ISCSI_PAD_LEN - len;
448 return len;
449}
450
451#endif