aboutsummaryrefslogtreecommitdiff
path: root/include/scsi/libiscsi.h
blob: 176353c117b6cb81b7ee6caef1e2a85a4ddc0fd0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
/*
 * iSCSI lib definitions
 *
 * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
 * Copyright (C) 2004 - 2006 Mike Christie
 * Copyright (C) 2004 - 2005 Dmitry Yusupov
 * Copyright (C) 2004 - 2005 Alex Aizman
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */
#ifndef LIBISCSI_H
#define LIBISCSI_H

#include <linux/types.h>
#include <linux/wait.h>
#include <linux/mutex.h>
#include <linux/timer.h>
#include <linux/workqueue.h>
#include <scsi/iscsi_proto.h>
#include <scsi/iscsi_if.h>

struct scsi_transport_template;
struct scsi_host_template;
struct scsi_device;
struct Scsi_Host;
struct scsi_cmnd;
struct socket;
struct iscsi_transport;
struct iscsi_cls_session;
struct iscsi_cls_conn;
struct iscsi_session;
struct iscsi_nopin;
struct device;

/* #define DEBUG_SCSI */
#ifdef DEBUG_SCSI
#define debug_scsi(fmt...) printk(KERN_INFO "iscsi: " fmt)
#else
#define debug_scsi(fmt...)
#endif

#define ISCSI_DEF_XMIT_CMDS_MAX	128	/* must be power of 2 */
#define ISCSI_MGMT_CMDS_MAX	16	/* must be power of 2 */

#define ISCSI_MGMT_ITT_OFFSET	0xa00

#define ISCSI_DEF_CMD_PER_LUN		32
#define ISCSI_MAX_CMD_PER_LUN		128

/* Task Mgmt states */
enum {
	TMF_INITIAL,
	TMF_QUEUED,
	TMF_SUCCESS,
	TMF_FAILED,
	TMF_TIMEDOUT,
	TMF_NOT_FOUND,
};

/* Connection suspend "bit" */
#define ISCSI_SUSPEND_BIT		1

#define ISCSI_ITT_MASK			(0xfff)
#define ISCSI_AGE_SHIFT			28
#define ISCSI_AGE_MASK			(0xf << ISCSI_AGE_SHIFT)

#define ISCSI_ADDRESS_BUF_LEN		64

enum {
	/* this is the maximum possible storage for AHSs */
	ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
				sizeof(struct iscsi_rlength_ahdr),
	ISCSI_DIGEST_SIZE = sizeof(__u32),
};


enum {
	ISCSI_TASK_COMPLETED,
	ISCSI_TASK_PENDING,
	ISCSI_TASK_RUNNING,
};

struct iscsi_task {
	/*
	 * Because LLDs allocate their hdr differently, this is a pointer
	 * and length to that storage. It must be setup at session
	 * creation time.
	 */
	struct iscsi_cmd	*hdr;
	unsigned short		hdr_max;
	unsigned short		hdr_len;	/* accumulated size of hdr used */
	int			itt;		/* this ITT */

	uint32_t		unsol_datasn;
	unsigned		imm_count;	/* imm-data (bytes)   */
	unsigned		unsol_count;	/* unsolicited (bytes)*/
	/* offset in unsolicited stream (bytes); */
	unsigned		unsol_offset;
	unsigned		data_count;	/* remaining Data-Out */
	char			*data;		/* mgmt payload */
	struct scsi_cmnd	*sc;		/* associated SCSI cmd*/
	struct iscsi_conn	*conn;		/* used connection    */

	/* state set/tested under session->lock */
	int			state;
	atomic_t		refcount;
	struct list_head	running;	/* running cmd list */
	void			*dd_data;	/* driver/transport data */
};

static inline void* iscsi_next_hdr(struct iscsi_task *task)
{
	return (void*)task->hdr + task->hdr_len;
}

/* Connection's states */
enum {
	ISCSI_CONN_INITIAL_STAGE,
	ISCSI_CONN_STARTED,
	ISCSI_CONN_STOPPED,
	ISCSI_CONN_CLEANUP_WAIT,
};

struct iscsi_conn {
	struct iscsi_cls_conn	*cls_conn;	/* ptr to class connection */
	void			*dd_data;	/* iscsi_transport data */
	struct iscsi_session	*session;	/* parent session */
	/*
	 * LLDs should set this lock. It protects the transport recv
	 * code
	 */
	rwlock_t		*recv_lock;
	/*
	 * conn_stop() flag: stop to recover, stop to terminate
	 */
        int			stop_stage;
	struct timer_list	transport_timer;
	unsigned long		last_recv;
	unsigned long		last_ping;
	int			ping_timeout;
	int			recv_timeout;
	struct iscsi_task 	*ping_task;

	/* iSCSI connection-wide sequencing */
	uint32_t		exp_statsn;

	/* control data */
	int			id;		/* CID */
	int			c_stage;	/* connection state */
	/*
	 * Preallocated buffer for pdus that have data but do not
	 * originate from scsi-ml. We never have two pdus using the
	 * buffer at the same time. It is only allocated to
	 * the default max recv size because the pdus we support
	 * should always fit in this buffer
	 */
	char			*data;
	struct iscsi_task 	*login_task;	/* mtask used for login/text */
	struct iscsi_task	*task;		/* xmit task in progress */

	/* xmit */
	struct list_head	mgmtqueue;	/* mgmt (control) xmit queue */
	struct list_head	mgmt_run_list;	/* list of control tasks */
	struct list_head	xmitqueue;	/* data-path cmd queue */
	struct list_head	run_list;	/* list of cmds in progress */
	struct list_head	requeue;	/* tasks needing another run */
	struct work_struct	xmitwork;	/* per-conn. xmit workqueue */
	unsigned long		suspend_tx;	/* suspend Tx */
	unsigned long		suspend_rx;	/* suspend Rx */

	/* abort */
	wait_queue_head_t	ehwait;		/* used in eh_abort() */
	struct iscsi_tm		tmhdr;
	struct timer_list	tmf_timer;
	int			tmf_state;	/* see TMF_INITIAL, etc.*/

	/* negotiated params */
	unsigned		max_recv_dlength; /* initiator_max_recv_dsl*/
	unsigned		max_xmit_dlength; /* target_max_recv_dsl */
	int			hdrdgst_en;
	int			datadgst_en;
	int			ifmarker_en;
	int			ofmarker_en;
	/* values userspace uses to id a conn */
	int			persistent_port;
	char			*persistent_address;
	/* remote portal currently connected to */
	int			portal_port;
	char			portal_address[ISCSI_ADDRESS_BUF_LEN];

	/* MIB-statistics */
	uint64_t		txdata_octets;
	uint64_t		rxdata_octets;
	uint32_t		scsicmd_pdus_cnt;
	uint32_t		dataout_pdus_cnt;
	uint32_t		scsirsp_pdus_cnt;
	uint32_t		datain_pdus_cnt;
	uint32_t		r2t_pdus_cnt;
	uint32_t		tmfcmd_pdus_cnt;
	int32_t			tmfrsp_pdus_cnt;

	/* custom statistics */
	uint32_t		eh_abort_cnt;
	uint32_t		fmr_unalign_cnt;
};

struct iscsi_pool {
	struct kfifo		*queue;		/* FIFO Queue */
	void			**pool;		/* Pool of elements */
	int			max;		/* Max number of elements */
};

/* Session's states */
enum {
	ISCSI_STATE_FREE = 1,
	ISCSI_STATE_LOGGED_IN,
	ISCSI_STATE_FAILED,
	ISCSI_STATE_TERMINATE,
	ISCSI_STATE_IN_RECOVERY,
	ISCSI_STATE_RECOVERY_FAILED,
	ISCSI_STATE_LOGGING_OUT,
};

struct iscsi_session {
	struct iscsi_cls_session *cls_session;
	/*
	 * Syncs up the scsi eh thread with the iscsi eh thread when sending
	 * task management functions. This must be taken before the session
	 * and recv lock.
	 */
	struct mutex		eh_mutex;

	/* iSCSI session-wide sequencing */
	uint32_t		cmdsn;
	uint32_t		exp_cmdsn;
	uint32_t		max_cmdsn;

	/* This tracks the reqs queued into the initiator */
	uint32_t		queued_cmdsn;

	/* configuration */
	int			abort_timeout;
	int			lu_reset_timeout;
	int			initial_r2t_en;
	unsigned		max_r2t;
	int			imm_data_en;
	unsigned		first_burst;
	unsigned		max_burst;
	int			time2wait;
	int			time2retain;
	int			pdu_inorder_en;
	int			dataseq_inorder_en;
	int			erl;
	int			fast_abort;
	int			tpgt;
	char			*username;
	char			*username_in;
	char			*password;
	char			*password_in;
	char			*targetname;
	/* control data */
	struct iscsi_transport	*tt;
	struct Scsi_Host	*host;
	struct iscsi_conn	*leadconn;	/* leading connection */
	spinlock_t		lock;		/* protects session state, *
						 * sequence numbers,       *
						 * session resources:      *
						 * - cmdpool,		   *
						 * - mgmtpool,		   *
						 * - r2tpool		   */
	int			state;		/* session state           */
	int			age;		/* counts session re-opens */

	int			scsi_cmds_max; 	/* max scsi commands */
	int			cmds_max;	/* size of cmds array */
	struct iscsi_task	**cmds;		/* Original Cmds arr */
	struct iscsi_pool	cmdpool;	/* PDU's pool */
};

struct iscsi_host {
	char			*initiatorname;
	/* hw address or netdev iscsi connection is bound to */
	char			*hwaddress;
	char			*netdev;
	/* local address */
	int			local_port;
	char			local_address[ISCSI_ADDRESS_BUF_LEN];
};

/*
 * scsi host template
 */
extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
extern int iscsi_eh_abort(struct scsi_cmnd *sc);
extern int iscsi_eh_host_reset(struct scsi_cmnd *sc);
extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
extern int iscsi_queuecommand(struct scsi_cmnd *sc,
			      void (*done)(struct scsi_cmnd *));

/*
 * iSCSI host helpers.
 */
#define iscsi_host_priv(_shost) \
	(shost_priv(_shost) + sizeof(struct iscsi_host))

extern int iscsi_host_set_param(struct Scsi_Host *shost,
				enum iscsi_host_param param, char *buf,
				int buflen);
extern int iscsi_host_get_param(struct Scsi_Host *shost,
				enum iscsi_host_param param, char *buf);
extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
					  int dd_data_size, uint16_t qdepth);
extern void iscsi_host_remove(struct Scsi_Host *shost);
extern void iscsi_host_free(struct Scsi_Host *shost);

/*
 * session management
 */
extern struct iscsi_cls_session *
iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
		    uint16_t, int, uint32_t);
extern void iscsi_session_teardown(struct iscsi_cls_session *);
extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
			   enum iscsi_param param, char *buf, int buflen);
extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
				   enum iscsi_param param, char *buf);

#define iscsi_session_printk(prefix, _sess, fmt, a...)	\
	iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)

/*
 * connection management
 */
extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
					       int, uint32_t);
extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
extern int iscsi_conn_start(struct iscsi_cls_conn *);
extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
			   int);
extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
				enum iscsi_param param, char *buf);
extern void iscsi_suspend_tx(struct iscsi_conn *conn);

#define iscsi_conn_printk(prefix, _c, fmt, a...) \
	iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
			      fmt, ##a)

/*
 * pdu and task processing
 */
extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
extern void iscsi_prep_unsolicit_data_pdu(struct iscsi_task *,
					struct iscsi_data *hdr);
extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
				char *, uint32_t);
extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
			      char *, int);
extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
extern void iscsi_requeue_task(struct iscsi_task *task);
extern void iscsi_put_task(struct iscsi_task *task);

/*
 * generic helpers
 */
extern void iscsi_pool_free(struct iscsi_pool *);
extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);

/*
 * inline functions to deal with padding.
 */
static inline unsigned int
iscsi_padded(unsigned int len)
{
	return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
}

static inline unsigned int
iscsi_padding(unsigned int len)
{
	len &= (ISCSI_PAD_LEN - 1);
	if (len)
		len = ISCSI_PAD_LEN - len;
	return len;
}

#endif