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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
34struct scsi_transport_template;
35struct scsi_host_template;
36struct scsi_device;
37struct Scsi_Host;
38struct scsi_cmnd;
39struct socket;
40struct iscsi_transport;
41struct iscsi_cls_session;
42struct iscsi_cls_conn;
43struct iscsi_session;
44struct iscsi_nopin;
45struct device;
46
47/* #define DEBUG_SCSI */
48#ifdef DEBUG_SCSI
49#define debug_scsi(fmt...) printk(KERN_INFO "iscsi: " fmt)
50#else
51#define debug_scsi(fmt...)
52#endif
53
54#define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
55#define ISCSI_MGMT_CMDS_MAX 15
56
57#define ISCSI_DEF_CMD_PER_LUN 32
58#define ISCSI_MAX_CMD_PER_LUN 128
59
60/* Task Mgmt states */
61enum {
62 TMF_INITIAL,
63 TMF_QUEUED,
64 TMF_SUCCESS,
65 TMF_FAILED,
66 TMF_TIMEDOUT,
67 TMF_NOT_FOUND,
68};
69
70/* Connection suspend "bit" */
71#define ISCSI_SUSPEND_BIT 1
72
73#define ISCSI_ITT_MASK (0x1fff)
74#define ISCSI_TOTAL_CMDS_MAX 4096
75/* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
76#define ISCSI_TOTAL_CMDS_MIN 16
77#define ISCSI_AGE_SHIFT 28
78#define ISCSI_AGE_MASK (0xf << ISCSI_AGE_SHIFT)
79
80#define ISCSI_ADDRESS_BUF_LEN 64
81
82enum {
83 /* this is the maximum possible storage for AHSs */
84 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
85 sizeof(struct iscsi_rlength_ahdr),
86 ISCSI_DIGEST_SIZE = sizeof(__u32),
87};
88
89
90enum {
91 ISCSI_TASK_COMPLETED,
92 ISCSI_TASK_PENDING,
93 ISCSI_TASK_RUNNING,
94};
95
96struct iscsi_task {
97 /*
98 * Because LLDs allocate their hdr differently, this is a pointer
99 * and length to that storage. It must be setup at session
100 * creation time.
101 */
102 struct iscsi_cmd *hdr;
103 unsigned short hdr_max;
104 unsigned short hdr_len; /* accumulated size of hdr used */
105 int itt; /* this ITT */
106
107 uint32_t unsol_datasn;
108 unsigned imm_count; /* imm-data (bytes) */
109 unsigned unsol_count; /* unsolicited (bytes)*/
110 /* offset in unsolicited stream (bytes); */
111 unsigned unsol_offset;
112 unsigned data_count; /* remaining Data-Out */
113 char *data; /* mgmt payload */
114 struct scsi_cmnd *sc; /* associated SCSI cmd*/
115 struct iscsi_conn *conn; /* used connection */
116
117 /* state set/tested under session->lock */
118 int state;
119 atomic_t refcount;
120 struct list_head running; /* running cmd list */
121 void *dd_data; /* driver/transport data */
122};
123
124static inline void* iscsi_next_hdr(struct iscsi_task *task)
125{
126 return (void*)task->hdr + task->hdr_len;
127}
128
129/* Connection's states */
130enum {
131 ISCSI_CONN_INITIAL_STAGE,
132 ISCSI_CONN_STARTED,
133 ISCSI_CONN_STOPPED,
134 ISCSI_CONN_CLEANUP_WAIT,
135};
136
137struct iscsi_conn {
138 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
139 void *dd_data; /* iscsi_transport data */
140 struct iscsi_session *session; /* parent session */
141 /*
142 * conn_stop() flag: stop to recover, stop to terminate
143 */
144 int stop_stage;
145 struct timer_list transport_timer;
146 unsigned long last_recv;
147 unsigned long last_ping;
148 int ping_timeout;
149 int recv_timeout;
150 struct iscsi_task *ping_task;
151
152 /* iSCSI connection-wide sequencing */
153 uint32_t exp_statsn;
154
155 /* control data */
156 int id; /* CID */
157 int c_stage; /* connection state */
158 /*
159 * Preallocated buffer for pdus that have data but do not
160 * originate from scsi-ml. We never have two pdus using the
161 * buffer at the same time. It is only allocated to
162 * the default max recv size because the pdus we support
163 * should always fit in this buffer
164 */
165 char *data;
166 struct iscsi_task *login_task; /* mtask used for login/text */
167 struct iscsi_task *task; /* xmit task in progress */
168
169 /* xmit */
170 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
171 struct list_head mgmt_run_list; /* list of control tasks */
172 struct list_head xmitqueue; /* data-path cmd queue */
173 struct list_head run_list; /* list of cmds in progress */
174 struct list_head requeue; /* tasks needing another run */
175 struct work_struct xmitwork; /* per-conn. xmit workqueue */
176 unsigned long suspend_tx; /* suspend Tx */
177 unsigned long suspend_rx; /* suspend Rx */
178
179 /* abort */
180 wait_queue_head_t ehwait; /* used in eh_abort() */
181 struct iscsi_tm tmhdr;
182 struct timer_list tmf_timer;
183 int tmf_state; /* see TMF_INITIAL, etc.*/
184
185 /* negotiated params */
186 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
187 unsigned max_xmit_dlength; /* target_max_recv_dsl */
188 int hdrdgst_en;
189 int datadgst_en;
190 int ifmarker_en;
191 int ofmarker_en;
192 /* values userspace uses to id a conn */
193 int persistent_port;
194 char *persistent_address;
195 /* remote portal currently connected to */
196 int portal_port;
197 char portal_address[ISCSI_ADDRESS_BUF_LEN];
198
199 /* MIB-statistics */
200 uint64_t txdata_octets;
201 uint64_t rxdata_octets;
202 uint32_t scsicmd_pdus_cnt;
203 uint32_t dataout_pdus_cnt;
204 uint32_t scsirsp_pdus_cnt;
205 uint32_t datain_pdus_cnt;
206 uint32_t r2t_pdus_cnt;
207 uint32_t tmfcmd_pdus_cnt;
208 int32_t tmfrsp_pdus_cnt;
209
210 /* custom statistics */
211 uint32_t eh_abort_cnt;
212 uint32_t fmr_unalign_cnt;
213};
214
215struct iscsi_pool {
216 struct kfifo *queue; /* FIFO Queue */
217 void **pool; /* Pool of elements */
218 int max; /* Max number of elements */
219};
220
221/* Session's states */
222enum {
223 ISCSI_STATE_FREE = 1,
224 ISCSI_STATE_LOGGED_IN,
225 ISCSI_STATE_FAILED,
226 ISCSI_STATE_TERMINATE,
227 ISCSI_STATE_IN_RECOVERY,
228 ISCSI_STATE_RECOVERY_FAILED,
229 ISCSI_STATE_LOGGING_OUT,
230};
231
232struct iscsi_session {
233 struct iscsi_cls_session *cls_session;
234 /*
235 * Syncs up the scsi eh thread with the iscsi eh thread when sending
236 * task management functions. This must be taken before the session
237 * and recv lock.
238 */
239 struct mutex eh_mutex;
240
241 /* iSCSI session-wide sequencing */
242 uint32_t cmdsn;
243 uint32_t exp_cmdsn;
244 uint32_t max_cmdsn;
245
246 /* This tracks the reqs queued into the initiator */
247 uint32_t queued_cmdsn;
248
249 /* configuration */
250 int abort_timeout;
251 int lu_reset_timeout;
252 int initial_r2t_en;
253 unsigned max_r2t;
254 int imm_data_en;
255 unsigned first_burst;
256 unsigned max_burst;
257 int time2wait;
258 int time2retain;
259 int pdu_inorder_en;
260 int dataseq_inorder_en;
261 int erl;
262 int fast_abort;
263 int tpgt;
264 char *username;
265 char *username_in;
266 char *password;
267 char *password_in;
268 char *targetname;
269 char *ifacename;
270 char *initiatorname;
271 /* control data */
272 struct iscsi_transport *tt;
273 struct Scsi_Host *host;
274 struct iscsi_conn *leadconn; /* leading connection */
275 spinlock_t lock; /* protects session state, *
276 * sequence numbers, *
277 * session resources: *
278 * - cmdpool, *
279 * - mgmtpool, *
280 * - r2tpool */
281 int state; /* session state */
282 int age; /* counts session re-opens */
283
284 int scsi_cmds_max; /* max scsi commands */
285 int cmds_max; /* size of cmds array */
286 struct iscsi_task **cmds; /* Original Cmds arr */
287 struct iscsi_pool cmdpool; /* PDU's pool */
288};
289
290enum {
291 ISCSI_HOST_SETUP,
292 ISCSI_HOST_REMOVED,
293};
294
295struct iscsi_host {
296 char *initiatorname;
297 /* hw address or netdev iscsi connection is bound to */
298 char *hwaddress;
299 char *netdev;
300 /* local address */
301 int local_port;
302 char local_address[ISCSI_ADDRESS_BUF_LEN];
303
304 wait_queue_head_t session_removal_wq;
305 /* protects sessions and state */
306 spinlock_t lock;
307 int num_sessions;
308 int state;
309};
310
311/*
312 * scsi host template
313 */
314extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
315extern int iscsi_eh_abort(struct scsi_cmnd *sc);
316extern int iscsi_eh_target_reset(struct scsi_cmnd *sc);
317extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
318extern int iscsi_queuecommand(struct scsi_cmnd *sc,
319 void (*done)(struct scsi_cmnd *));
320
321/*
322 * iSCSI host helpers.
323 */
324#define iscsi_host_priv(_shost) \
325 (shost_priv(_shost) + sizeof(struct iscsi_host))
326
327extern int iscsi_host_set_param(struct Scsi_Host *shost,
328 enum iscsi_host_param param, char *buf,
329 int buflen);
330extern int iscsi_host_get_param(struct Scsi_Host *shost,
331 enum iscsi_host_param param, char *buf);
332extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
333extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
334 int dd_data_size, uint16_t qdepth);
335extern void iscsi_host_remove(struct Scsi_Host *shost);
336extern void iscsi_host_free(struct Scsi_Host *shost);
337
338/*
339 * session management
340 */
341extern struct iscsi_cls_session *
342iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
343 uint16_t, int, uint32_t, unsigned int);
344extern void iscsi_session_teardown(struct iscsi_cls_session *);
345extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
346extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
347 enum iscsi_param param, char *buf, int buflen);
348extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
349 enum iscsi_param param, char *buf);
350
351#define iscsi_session_printk(prefix, _sess, fmt, a...) \
352 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
353
354/*
355 * connection management
356 */
357extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
358 int, uint32_t);
359extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
360extern int iscsi_conn_start(struct iscsi_cls_conn *);
361extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
362extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
363 int);
364extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
365extern void iscsi_session_failure(struct iscsi_cls_session *cls_session,
366 enum iscsi_err err);
367extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
368 enum iscsi_param param, char *buf);
369extern void iscsi_suspend_tx(struct iscsi_conn *conn);
370
371#define iscsi_conn_printk(prefix, _c, fmt, a...) \
372 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
373 fmt, ##a)
374
375/*
376 * pdu and task processing
377 */
378extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
379extern void iscsi_prep_unsolicit_data_pdu(struct iscsi_task *,
380 struct iscsi_data *hdr);
381extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
382 char *, uint32_t);
383extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
384 char *, int);
385extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
386 char *, int);
387extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
388extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
389extern void iscsi_requeue_task(struct iscsi_task *task);
390extern void iscsi_put_task(struct iscsi_task *task);
391extern void __iscsi_get_task(struct iscsi_task *task);
392
393/*
394 * generic helpers
395 */
396extern void iscsi_pool_free(struct iscsi_pool *);
397extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
398
399/*
400 * inline functions to deal with padding.
401 */
402static inline unsigned int
403iscsi_padded(unsigned int len)
404{
405 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
406}
407
408static inline unsigned int
409iscsi_padding(unsigned int len)
410{
411 len &= (ISCSI_PAD_LEN - 1);
412 if (len)
413 len = ISCSI_PAD_LEN - len;
414 return len;
415}
416
417#endif