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Linux kernel mirror (for testing)
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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/mutex.h>
28#include <linux/timer.h>
29#include <linux/workqueue.h>
30#include <scsi/iscsi_proto.h>
31#include <scsi/iscsi_if.h>
32
33struct scsi_transport_template;
34struct scsi_device;
35struct Scsi_Host;
36struct scsi_cmnd;
37struct socket;
38struct iscsi_transport;
39struct iscsi_cls_session;
40struct iscsi_cls_conn;
41struct iscsi_session;
42struct iscsi_nopin;
43
44/* #define DEBUG_SCSI */
45#ifdef DEBUG_SCSI
46#define debug_scsi(fmt...) printk(KERN_INFO "iscsi: " fmt)
47#else
48#define debug_scsi(fmt...)
49#endif
50
51#define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
52#define ISCSI_MGMT_CMDS_MAX 16 /* must be power of 2 */
53
54#define ISCSI_MGMT_ITT_OFFSET 0xa00
55
56#define ISCSI_DEF_CMD_PER_LUN 32
57#define ISCSI_MAX_CMD_PER_LUN 128
58
59/* Task Mgmt states */
60enum {
61 TMF_INITIAL,
62 TMF_QUEUED,
63 TMF_SUCCESS,
64 TMF_FAILED,
65 TMF_TIMEDOUT,
66 TMF_NOT_FOUND,
67};
68
69/* Connection suspend "bit" */
70#define ISCSI_SUSPEND_BIT 1
71
72#define ISCSI_ITT_MASK (0xfff)
73#define ISCSI_CID_SHIFT 12
74#define ISCSI_CID_MASK (0xffff << ISCSI_CID_SHIFT)
75#define ISCSI_AGE_SHIFT 28
76#define ISCSI_AGE_MASK (0xf << ISCSI_AGE_SHIFT)
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
87struct iscsi_mgmt_task {
88 /*
89 * Becuae LLDs allocate their hdr differently, this is a pointer to
90 * that storage. It must be setup at session creation time.
91 */
92 struct iscsi_hdr *hdr;
93 char *data; /* mgmt payload */
94 unsigned data_count; /* counts data to be sent */
95 uint32_t itt; /* this ITT */
96 void *dd_data; /* driver/transport data */
97 struct list_head running;
98};
99
100enum {
101 ISCSI_TASK_COMPLETED,
102 ISCSI_TASK_PENDING,
103 ISCSI_TASK_RUNNING,
104};
105
106struct iscsi_cmd_task {
107 /*
108 * Because LLDs allocate their hdr differently, this is a pointer
109 * and length to that storage. It must be setup at session
110 * creation time.
111 */
112 struct iscsi_cmd *hdr;
113 unsigned short hdr_max;
114 unsigned short hdr_len; /* accumulated size of hdr used */
115 int itt; /* this ITT */
116
117 uint32_t unsol_datasn;
118 unsigned imm_count; /* imm-data (bytes) */
119 unsigned unsol_count; /* unsolicited (bytes)*/
120 /* offset in unsolicited stream (bytes); */
121 unsigned unsol_offset;
122 unsigned data_count; /* remaining Data-Out */
123 struct scsi_cmnd *sc; /* associated SCSI cmd*/
124 struct iscsi_conn *conn; /* used connection */
125
126 /* state set/tested under session->lock */
127 int state;
128 atomic_t refcount;
129 struct list_head running; /* running cmd list */
130 void *dd_data; /* driver/transport data */
131};
132
133static inline void* iscsi_next_hdr(struct iscsi_cmd_task *ctask)
134{
135 return (void*)ctask->hdr + ctask->hdr_len;
136}
137
138struct iscsi_conn {
139 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
140 void *dd_data; /* iscsi_transport data */
141 struct iscsi_session *session; /* parent session */
142 /*
143 * LLDs should set this lock. It protects the transport recv
144 * code
145 */
146 rwlock_t *recv_lock;
147 /*
148 * conn_stop() flag: stop to recover, stop to terminate
149 */
150 int stop_stage;
151 struct timer_list transport_timer;
152 unsigned long last_recv;
153 unsigned long last_ping;
154 int ping_timeout;
155 int recv_timeout;
156 struct iscsi_mgmt_task *ping_mtask;
157
158 /* iSCSI connection-wide sequencing */
159 uint32_t exp_statsn;
160
161 /* control data */
162 int id; /* CID */
163 int c_stage; /* connection state */
164 /*
165 * Preallocated buffer for pdus that have data but do not
166 * originate from scsi-ml. We never have two pdus using the
167 * buffer at the same time. It is only allocated to
168 * the default max recv size because the pdus we support
169 * should always fit in this buffer
170 */
171 char *data;
172 struct iscsi_mgmt_task *login_mtask; /* mtask used for login/text */
173 struct iscsi_mgmt_task *mtask; /* xmit mtask in progress */
174 struct iscsi_cmd_task *ctask; /* xmit ctask in progress */
175
176 /* xmit */
177 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
178 struct list_head mgmt_run_list; /* list of control tasks */
179 struct list_head xmitqueue; /* data-path cmd queue */
180 struct list_head run_list; /* list of cmds in progress */
181 struct list_head requeue; /* tasks needing another run */
182 struct work_struct xmitwork; /* per-conn. xmit workqueue */
183 unsigned long suspend_tx; /* suspend Tx */
184 unsigned long suspend_rx; /* suspend Rx */
185
186 /* abort */
187 wait_queue_head_t ehwait; /* used in eh_abort() */
188 struct iscsi_tm tmhdr;
189 struct timer_list tmf_timer;
190 int tmf_state; /* see TMF_INITIAL, etc.*/
191
192 /* negotiated params */
193 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
194 unsigned max_xmit_dlength; /* target_max_recv_dsl */
195 int hdrdgst_en;
196 int datadgst_en;
197 int ifmarker_en;
198 int ofmarker_en;
199 /* values userspace uses to id a conn */
200 int persistent_port;
201 char *persistent_address;
202 /* remote portal currently connected to */
203 int portal_port;
204 char portal_address[ISCSI_ADDRESS_BUF_LEN];
205 /* local address */
206 int local_port;
207 char local_address[ISCSI_ADDRESS_BUF_LEN];
208
209 /* MIB-statistics */
210 uint64_t txdata_octets;
211 uint64_t rxdata_octets;
212 uint32_t scsicmd_pdus_cnt;
213 uint32_t dataout_pdus_cnt;
214 uint32_t scsirsp_pdus_cnt;
215 uint32_t datain_pdus_cnt;
216 uint32_t r2t_pdus_cnt;
217 uint32_t tmfcmd_pdus_cnt;
218 int32_t tmfrsp_pdus_cnt;
219
220 /* custom statistics */
221 uint32_t eh_abort_cnt;
222};
223
224struct iscsi_pool {
225 struct kfifo *queue; /* FIFO Queue */
226 void **pool; /* Pool of elements */
227 int max; /* Max number of elements */
228};
229
230struct iscsi_session {
231 /*
232 * Syncs up the scsi eh thread with the iscsi eh thread when sending
233 * task management functions. This must be taken before the session
234 * and recv lock.
235 */
236 struct mutex eh_mutex;
237
238 /* iSCSI session-wide sequencing */
239 uint32_t cmdsn;
240 uint32_t exp_cmdsn;
241 uint32_t max_cmdsn;
242
243 /* This tracks the reqs queued into the initiator */
244 uint32_t queued_cmdsn;
245
246 /* configuration */
247 int abort_timeout;
248 int lu_reset_timeout;
249 int initial_r2t_en;
250 unsigned max_r2t;
251 int imm_data_en;
252 unsigned first_burst;
253 unsigned max_burst;
254 int time2wait;
255 int time2retain;
256 int pdu_inorder_en;
257 int dataseq_inorder_en;
258 int erl;
259 int fast_abort;
260 int tpgt;
261 char *username;
262 char *username_in;
263 char *password;
264 char *password_in;
265 char *targetname;
266 char *initiatorname;
267 /* hw address or netdev iscsi connection is bound to */
268 char *hwaddress;
269 char *netdev;
270 /* control data */
271 struct iscsi_transport *tt;
272 struct Scsi_Host *host;
273 struct iscsi_conn *leadconn; /* leading connection */
274 spinlock_t lock; /* protects session state, *
275 * sequence numbers, *
276 * session resources: *
277 * - cmdpool, *
278 * - mgmtpool, *
279 * - r2tpool */
280 int state; /* session state */
281 int age; /* counts session re-opens */
282
283 int cmds_max; /* size of cmds array */
284 struct iscsi_cmd_task **cmds; /* Original Cmds arr */
285 struct iscsi_pool cmdpool; /* PDU's pool */
286 int mgmtpool_max; /* size of mgmt array */
287 struct iscsi_mgmt_task **mgmt_cmds; /* Original mgmt arr */
288 struct iscsi_pool mgmtpool; /* Mgmt PDU's pool */
289};
290
291/*
292 * scsi host template
293 */
294extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
295extern int iscsi_eh_abort(struct scsi_cmnd *sc);
296extern int iscsi_eh_host_reset(struct scsi_cmnd *sc);
297extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
298extern int iscsi_queuecommand(struct scsi_cmnd *sc,
299 void (*done)(struct scsi_cmnd *));
300
301
302/*
303 * iSCSI host helpers.
304 */
305extern int iscsi_host_set_param(struct Scsi_Host *shost,
306 enum iscsi_host_param param, char *buf,
307 int buflen);
308extern int iscsi_host_get_param(struct Scsi_Host *shost,
309 enum iscsi_host_param param, char *buf);
310
311/*
312 * session management
313 */
314extern struct iscsi_cls_session *
315iscsi_session_setup(struct iscsi_transport *, struct scsi_transport_template *,
316 uint16_t, uint16_t, int, int, uint32_t, uint32_t *);
317extern void iscsi_session_teardown(struct iscsi_cls_session *);
318extern struct iscsi_session *class_to_transport_session(struct iscsi_cls_session *);
319extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
320extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
321 enum iscsi_param param, char *buf, int buflen);
322extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
323 enum iscsi_param param, char *buf);
324
325#define session_to_cls(_sess) \
326 hostdata_session(_sess->host->hostdata)
327
328/*
329 * connection management
330 */
331extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
332 uint32_t);
333extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
334extern int iscsi_conn_start(struct iscsi_cls_conn *);
335extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
336extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
337 int);
338extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
339extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
340 enum iscsi_param param, char *buf);
341
342/*
343 * pdu and task processing
344 */
345extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
346extern void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *,
347 struct iscsi_data *hdr);
348extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
349 char *, uint32_t);
350extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
351 char *, int);
352extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
353 char *, int);
354extern int iscsi_verify_itt(struct iscsi_conn *, struct iscsi_hdr *,
355 uint32_t *);
356extern void iscsi_requeue_ctask(struct iscsi_cmd_task *ctask);
357extern void iscsi_free_mgmt_task(struct iscsi_conn *conn,
358 struct iscsi_mgmt_task *mtask);
359
360/*
361 * generic helpers
362 */
363extern void iscsi_pool_free(struct iscsi_pool *);
364extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
365
366/*
367 * inline functions to deal with padding.
368 */
369static inline unsigned int
370iscsi_padded(unsigned int len)
371{
372 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
373}
374
375static inline unsigned int
376iscsi_padding(unsigned int len)
377{
378 len &= (ISCSI_PAD_LEN - 1);
379 if (len)
380 len = ISCSI_PAD_LEN - len;
381 return len;
382}
383
384#endif