xref: /openbmc/linux/include/scsi/libiscsi.h (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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 
33 struct scsi_transport_template;
34 struct scsi_device;
35 struct Scsi_Host;
36 struct scsi_cmnd;
37 struct socket;
38 struct iscsi_transport;
39 struct iscsi_cls_session;
40 struct iscsi_cls_conn;
41 struct iscsi_session;
42 struct 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 */
60 #define TMABORT_INITIAL			0x0
61 #define TMABORT_SUCCESS			0x1
62 #define TMABORT_FAILED			0x2
63 #define TMABORT_TIMEDOUT		0x3
64 #define TMABORT_NOT_FOUND		0x4
65 
66 /* Connection suspend "bit" */
67 #define ISCSI_SUSPEND_BIT		1
68 
69 #define ISCSI_ITT_MASK			(0xfff)
70 #define ISCSI_CID_SHIFT			12
71 #define ISCSI_CID_MASK			(0xffff << ISCSI_CID_SHIFT)
72 #define ISCSI_AGE_SHIFT			28
73 #define ISCSI_AGE_MASK			(0xf << ISCSI_AGE_SHIFT)
74 
75 #define ISCSI_ADDRESS_BUF_LEN		64
76 
77 struct iscsi_mgmt_task {
78 	/*
79 	 * Becuae LLDs allocate their hdr differently, this is a pointer to
80 	 * that storage. It must be setup at session creation time.
81 	 */
82 	struct iscsi_hdr	*hdr;
83 	char			*data;		/* mgmt payload */
84 	unsigned		data_count;	/* counts data to be sent */
85 	uint32_t		itt;		/* this ITT */
86 	void			*dd_data;	/* driver/transport data */
87 	struct list_head	running;
88 };
89 
90 enum {
91 	ISCSI_TASK_COMPLETED,
92 	ISCSI_TASK_PENDING,
93 	ISCSI_TASK_RUNNING,
94 	ISCSI_TASK_ABORTING,
95 };
96 
97 struct iscsi_cmd_task {
98 	/*
99 	 * Becuae LLDs allocate their hdr differently, this is a pointer to
100 	 * that storage. It must be setup at session creation time.
101 	 */
102 	struct iscsi_cmd	*hdr;
103 	int			itt;		/* this ITT */
104 
105 	uint32_t		unsol_datasn;
106 	unsigned		imm_count;	/* imm-data (bytes)   */
107 	unsigned		unsol_count;	/* unsolicited (bytes)*/
108 	/* offset in unsolicited stream (bytes); */
109 	unsigned		unsol_offset;
110 	unsigned		data_count;	/* remaining Data-Out */
111 	struct scsi_cmnd	*sc;		/* associated SCSI cmd*/
112 	struct iscsi_conn	*conn;		/* used connection    */
113 	struct iscsi_mgmt_task	*mtask;		/* tmf mtask in progr */
114 
115 	/* state set/tested under session->lock */
116 	int			state;
117 	atomic_t		refcount;
118 	struct list_head	running;	/* running cmd list */
119 	void			*dd_data;	/* driver/transport data */
120 };
121 
122 struct iscsi_conn {
123 	struct iscsi_cls_conn	*cls_conn;	/* ptr to class connection */
124 	void			*dd_data;	/* iscsi_transport data */
125 	struct iscsi_session	*session;	/* parent session */
126 	/*
127 	 * LLDs should set this lock. It protects the transport recv
128 	 * code
129 	 */
130 	rwlock_t		*recv_lock;
131 	/*
132 	 * conn_stop() flag: stop to recover, stop to terminate
133 	 */
134         int			stop_stage;
135 
136 	/* iSCSI connection-wide sequencing */
137 	uint32_t		exp_statsn;
138 
139 	/* control data */
140 	int			id;		/* CID */
141 	int			c_stage;	/* connection state */
142 	/*
143 	 * Preallocated buffer for pdus that have data but do not
144 	 * originate from scsi-ml. We never have two pdus using the
145 	 * buffer at the same time. It is only allocated to
146 	 * the default max recv size because the pdus we support
147 	 * should always fit in this buffer
148 	 */
149 	char			*data;
150 	struct iscsi_mgmt_task	*login_mtask;	/* mtask used for login/text */
151 	struct iscsi_mgmt_task	*mtask;		/* xmit mtask in progress */
152 	struct iscsi_cmd_task	*ctask;		/* xmit ctask in progress */
153 
154 	/* xmit */
155 	struct kfifo		*mgmtqueue;	/* mgmt (control) xmit queue */
156 	struct list_head	mgmt_run_list;	/* list of control tasks */
157 	struct list_head	xmitqueue;	/* data-path cmd queue */
158 	struct list_head	run_list;	/* list of cmds in progress */
159 	struct work_struct	xmitwork;	/* per-conn. xmit workqueue */
160 	unsigned long		suspend_tx;	/* suspend Tx */
161 	unsigned long		suspend_rx;	/* suspend Rx */
162 
163 	/* abort */
164 	wait_queue_head_t	ehwait;		/* used in eh_abort() */
165 	struct iscsi_tm		tmhdr;
166 	struct timer_list	tmabort_timer;
167 	int			tmabort_state;	/* see TMABORT_INITIAL, etc.*/
168 
169 	/* negotiated params */
170 	unsigned		max_recv_dlength; /* initiator_max_recv_dsl*/
171 	unsigned		max_xmit_dlength; /* target_max_recv_dsl */
172 	int			hdrdgst_en;
173 	int			datadgst_en;
174 	int			ifmarker_en;
175 	int			ofmarker_en;
176 	/* values userspace uses to id a conn */
177 	int			persistent_port;
178 	char			*persistent_address;
179 	/* remote portal currently connected to */
180 	int			portal_port;
181 	char			portal_address[ISCSI_ADDRESS_BUF_LEN];
182 	/* local address */
183 	int			local_port;
184 	char			local_address[ISCSI_ADDRESS_BUF_LEN];
185 
186 	/* MIB-statistics */
187 	uint64_t		txdata_octets;
188 	uint64_t		rxdata_octets;
189 	uint32_t		scsicmd_pdus_cnt;
190 	uint32_t		dataout_pdus_cnt;
191 	uint32_t		scsirsp_pdus_cnt;
192 	uint32_t		datain_pdus_cnt;
193 	uint32_t		r2t_pdus_cnt;
194 	uint32_t		tmfcmd_pdus_cnt;
195 	int32_t			tmfrsp_pdus_cnt;
196 
197 	/* custom statistics */
198 	uint32_t		eh_abort_cnt;
199 };
200 
201 struct iscsi_queue {
202 	struct kfifo		*queue;		/* FIFO Queue */
203 	void			**pool;		/* Pool of elements */
204 	int			max;		/* Max number of elements */
205 };
206 
207 struct iscsi_session {
208 	/*
209 	 * Syncs up the scsi eh thread with the iscsi eh thread when sending
210 	 * task management functions. This must be taken before the session
211 	 * and recv lock.
212 	 */
213 	struct mutex		eh_mutex;
214 
215 	/* iSCSI session-wide sequencing */
216 	uint32_t		cmdsn;
217 	uint32_t		exp_cmdsn;
218 	uint32_t		max_cmdsn;
219 
220 	/* This tracks the reqs queued into the initiator */
221 	uint32_t		queued_cmdsn;
222 
223 	/* configuration */
224 	int			initial_r2t_en;
225 	unsigned		max_r2t;
226 	int			imm_data_en;
227 	unsigned		first_burst;
228 	unsigned		max_burst;
229 	int			time2wait;
230 	int			time2retain;
231 	int			pdu_inorder_en;
232 	int			dataseq_inorder_en;
233 	int			erl;
234 	int			tpgt;
235 	char			*username;
236 	char			*username_in;
237 	char			*password;
238 	char			*password_in;
239 	char			*targetname;
240 	char			*initiatorname;
241 	/* hw address or netdev iscsi connection is bound to */
242 	char			*hwaddress;
243 	char			*netdev;
244 	/* control data */
245 	struct iscsi_transport	*tt;
246 	struct Scsi_Host	*host;
247 	struct iscsi_conn	*leadconn;	/* leading connection */
248 	spinlock_t		lock;		/* protects session state, *
249 						 * sequence numbers,       *
250 						 * session resources:      *
251 						 * - cmdpool,		   *
252 						 * - mgmtpool,		   *
253 						 * - r2tpool		   */
254 	int			state;		/* session state           */
255 	int			age;		/* counts session re-opens */
256 
257 	int			cmds_max;	/* size of cmds array */
258 	struct iscsi_cmd_task	**cmds;		/* Original Cmds arr */
259 	struct iscsi_queue	cmdpool;	/* PDU's pool */
260 	int			mgmtpool_max;	/* size of mgmt array */
261 	struct iscsi_mgmt_task	**mgmt_cmds;	/* Original mgmt arr */
262 	struct iscsi_queue	mgmtpool;	/* Mgmt PDU's pool */
263 };
264 
265 /*
266  * scsi host template
267  */
268 extern int iscsi_change_queue_depth(struct scsi_device *sdev, int depth);
269 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
270 extern int iscsi_eh_host_reset(struct scsi_cmnd *sc);
271 extern int iscsi_queuecommand(struct scsi_cmnd *sc,
272 			      void (*done)(struct scsi_cmnd *));
273 
274 
275 /*
276  * iSCSI host helpers.
277  */
278 extern int iscsi_host_set_param(struct Scsi_Host *shost,
279 				enum iscsi_host_param param, char *buf,
280 				int buflen);
281 extern int iscsi_host_get_param(struct Scsi_Host *shost,
282 				enum iscsi_host_param param, char *buf);
283 
284 /*
285  * session management
286  */
287 extern struct iscsi_cls_session *
288 iscsi_session_setup(struct iscsi_transport *, struct scsi_transport_template *,
289 		    uint16_t, uint16_t, int, int, uint32_t, uint32_t *);
290 extern void iscsi_session_teardown(struct iscsi_cls_session *);
291 extern struct iscsi_session *class_to_transport_session(struct iscsi_cls_session *);
292 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
293 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
294 			   enum iscsi_param param, char *buf, int buflen);
295 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
296 				   enum iscsi_param param, char *buf);
297 
298 #define session_to_cls(_sess) \
299 	hostdata_session(_sess->host->hostdata)
300 
301 /*
302  * connection management
303  */
304 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
305 					       uint32_t);
306 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
307 extern int iscsi_conn_start(struct iscsi_cls_conn *);
308 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
309 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
310 			   int);
311 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
312 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
313 				enum iscsi_param param, char *buf);
314 
315 /*
316  * pdu and task processing
317  */
318 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
319 extern void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *,
320 					struct iscsi_data *hdr);
321 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
322 				char *, uint32_t);
323 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
324 			      char *, int);
325 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
326 				char *, int);
327 extern int iscsi_verify_itt(struct iscsi_conn *, struct iscsi_hdr *,
328 			    uint32_t *);
329 
330 /*
331  * generic helpers
332  */
333 extern void iscsi_pool_free(struct iscsi_queue *, void **);
334 extern int iscsi_pool_init(struct iscsi_queue *, int, void ***, int);
335 
336 #endif
337