1 /*
2  * iSCSI transport class definitions
3  *
4  * Copyright (C) IBM Corporation, 2004
5  * Copyright (C) Mike Christie, 2004 - 2006
6  * Copyright (C) Dmitry Yusupov, 2004 - 2005
7  * Copyright (C) Alex Aizman, 2004 - 2005
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 SCSI_TRANSPORT_ISCSI_H
24 #define SCSI_TRANSPORT_ISCSI_H
25 
26 #include <linux/device.h>
27 #include <linux/list.h>
28 #include <linux/mutex.h>
29 #include <scsi/iscsi_if.h>
30 
31 struct scsi_transport_template;
32 struct iscsi_transport;
33 struct iscsi_endpoint;
34 struct Scsi_Host;
35 struct scsi_cmnd;
36 struct iscsi_cls_conn;
37 struct iscsi_conn;
38 struct iscsi_task;
39 struct sockaddr;
40 struct iscsi_iface;
41 struct bsg_job;
42 struct iscsi_bus_flash_session;
43 struct iscsi_bus_flash_conn;
44 
45 /**
46  * struct iscsi_transport - iSCSI Transport template
47  *
48  * @name:		transport name
49  * @caps:		iSCSI Data-Path capabilities
50  * @create_session:	create new iSCSI session object
51  * @destroy_session:	destroy existing iSCSI session object
52  * @create_conn:	create new iSCSI connection
53  * @bind_conn:		associate this connection with existing iSCSI session
54  *			and specified transport descriptor
55  * @destroy_conn:	destroy inactive iSCSI connection
56  * @set_param:		set iSCSI parameter. Return 0 on success, -ENODATA
57  *			when param is not supported, and a -Exx value on other
58  *			error.
59  * @get_param		get iSCSI parameter. Must return number of bytes
60  *			copied to buffer on success, -ENODATA when param
61  *			is not supported, and a -Exx value on other error
62  * @start_conn:		set connection to be operational
63  * @stop_conn:		suspend/recover/terminate connection
64  * @send_pdu:		send iSCSI PDU, Login, Logout, NOP-Out, Reject, Text.
65  * @session_recovery_timedout: notify LLD a block during recovery timed out
66  * @init_task:		Initialize a iscsi_task and any internal structs.
67  *			When offloading the data path, this is called from
68  *			queuecommand with the session lock, or from the
69  *			iscsi_conn_send_pdu context with the session lock.
70  *			When not offloading the data path, this is called
71  *			from the scsi work queue without the session lock.
72  * @xmit_task		Requests LLD to transfer cmd task. Returns 0 or the
73  *			the number of bytes transferred on success, and -Exyz
74  *			value on error. When offloading the data path, this
75  *			is called from queuecommand with the session lock, or
76  *			from the iscsi_conn_send_pdu context with the session
77  *			lock. When not offloading the data path, this is called
78  *			from the scsi work queue without the session lock.
79  * @cleanup_task:	requests LLD to fail task. Called with session lock
80  *			and after the connection has been suspended and
81  *			terminated during recovery. If called
82  *			from abort task then connection is not suspended
83  *			or terminated but sk_callback_lock is held
84  *
85  * Template API provided by iSCSI Transport
86  */
87 struct iscsi_transport {
88 	struct module *owner;
89 	char *name;
90 	unsigned int caps;
91 
92 	struct iscsi_cls_session *(*create_session) (struct iscsi_endpoint *ep,
93 					uint16_t cmds_max, uint16_t qdepth,
94 					uint32_t sn);
95 	void (*destroy_session) (struct iscsi_cls_session *session);
96 	struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess,
97 				uint32_t cid);
98 	int (*bind_conn) (struct iscsi_cls_session *session,
99 			  struct iscsi_cls_conn *cls_conn,
100 			  uint64_t transport_eph, int is_leading);
101 	int (*start_conn) (struct iscsi_cls_conn *conn);
102 	void (*stop_conn) (struct iscsi_cls_conn *conn, int flag);
103 	void (*destroy_conn) (struct iscsi_cls_conn *conn);
104 	int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param,
105 			  char *buf, int buflen);
106 	int (*get_ep_param) (struct iscsi_endpoint *ep, enum iscsi_param param,
107 			     char *buf);
108 	int (*get_conn_param) (struct iscsi_cls_conn *conn,
109 			       enum iscsi_param param, char *buf);
110 	int (*get_session_param) (struct iscsi_cls_session *session,
111 				  enum iscsi_param param, char *buf);
112 	int (*get_host_param) (struct Scsi_Host *shost,
113 				enum iscsi_host_param param, char *buf);
114 	int (*set_host_param) (struct Scsi_Host *shost,
115 			       enum iscsi_host_param param, char *buf,
116 			       int buflen);
117 	int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
118 			 char *data, uint32_t data_size);
119 	void (*get_stats) (struct iscsi_cls_conn *conn,
120 			   struct iscsi_stats *stats);
121 
122 	int (*init_task) (struct iscsi_task *task);
123 	int (*xmit_task) (struct iscsi_task *task);
124 	void (*cleanup_task) (struct iscsi_task *task);
125 
126 	int (*alloc_pdu) (struct iscsi_task *task, uint8_t opcode);
127 	int (*xmit_pdu) (struct iscsi_task *task);
128 	int (*init_pdu) (struct iscsi_task *task, unsigned int offset,
129 			 unsigned int count);
130 	void (*parse_pdu_itt) (struct iscsi_conn *conn, itt_t itt,
131 			       int *index, int *age);
132 
133 	void (*session_recovery_timedout) (struct iscsi_cls_session *session);
134 	struct iscsi_endpoint *(*ep_connect) (struct Scsi_Host *shost,
135 					      struct sockaddr *dst_addr,
136 					      int non_blocking);
137 	int (*ep_poll) (struct iscsi_endpoint *ep, int timeout_ms);
138 	void (*ep_disconnect) (struct iscsi_endpoint *ep);
139 	int (*tgt_dscvr) (struct Scsi_Host *shost, enum iscsi_tgt_dscvr type,
140 			  uint32_t enable, struct sockaddr *dst_addr);
141 	int (*set_path) (struct Scsi_Host *shost, struct iscsi_path *params);
142 	int (*set_iface_param) (struct Scsi_Host *shost, void *data,
143 				uint32_t len);
144 	int (*get_iface_param) (struct iscsi_iface *iface,
145 				enum iscsi_param_type param_type,
146 				int param, char *buf);
147 	umode_t (*attr_is_visible)(int param_type, int param);
148 	int (*bsg_request)(struct bsg_job *job);
149 	int (*send_ping) (struct Scsi_Host *shost, uint32_t iface_num,
150 			  uint32_t iface_type, uint32_t payload_size,
151 			  uint32_t pid, struct sockaddr *dst_addr);
152 	int (*get_chap) (struct Scsi_Host *shost, uint16_t chap_tbl_idx,
153 			 uint32_t *num_entries, char *buf);
154 	int (*delete_chap) (struct Scsi_Host *shost, uint16_t chap_tbl_idx);
155 	int (*get_flashnode_param) (struct iscsi_bus_flash_session *fnode_sess,
156 				    int param, char *buf);
157 	int (*set_flashnode_param) (struct iscsi_bus_flash_session *fnode_sess,
158 				    struct iscsi_bus_flash_conn *fnode_conn,
159 				    void *data, int len);
160 	int (*new_flashnode) (struct Scsi_Host *shost, const char *buf,
161 			      int len);
162 	int (*del_flashnode) (struct iscsi_bus_flash_session *fnode_sess);
163 	int (*login_flashnode) (struct iscsi_bus_flash_session *fnode_sess,
164 				struct iscsi_bus_flash_conn *fnode_conn);
165 	int (*logout_flashnode) (struct iscsi_bus_flash_session *fnode_sess,
166 				 struct iscsi_bus_flash_conn *fnode_conn);
167 	int (*logout_flashnode_sid) (struct iscsi_cls_session *cls_sess);
168 };
169 
170 /*
171  * transport registration upcalls
172  */
173 extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt);
174 extern int iscsi_unregister_transport(struct iscsi_transport *tt);
175 
176 /*
177  * control plane upcalls
178  */
179 extern void iscsi_conn_error_event(struct iscsi_cls_conn *conn,
180 				   enum iscsi_err error);
181 extern void iscsi_conn_login_event(struct iscsi_cls_conn *conn,
182 				   enum iscsi_conn_state state);
183 extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
184 			  char *data, uint32_t data_size);
185 
186 extern int iscsi_offload_mesg(struct Scsi_Host *shost,
187 			      struct iscsi_transport *transport, uint32_t type,
188 			      char *data, uint16_t data_size);
189 
190 extern void iscsi_post_host_event(uint32_t host_no,
191 				  struct iscsi_transport *transport,
192 				  enum iscsi_host_event_code code,
193 				  uint32_t data_size,
194 				  uint8_t *data);
195 
196 extern void iscsi_ping_comp_event(uint32_t host_no,
197 				  struct iscsi_transport *transport,
198 				  uint32_t status, uint32_t pid,
199 				  uint32_t data_size, uint8_t *data);
200 
201 struct iscsi_cls_conn {
202 	struct list_head conn_list;	/* item in connlist */
203 	void *dd_data;			/* LLD private data */
204 	struct iscsi_transport *transport;
205 	uint32_t cid;			/* connection id */
206 	struct mutex ep_mutex;
207 	struct iscsi_endpoint *ep;
208 
209 	struct device dev;		/* sysfs transport/container device */
210 };
211 
212 #define iscsi_dev_to_conn(_dev) \
213 	container_of(_dev, struct iscsi_cls_conn, dev)
214 
215 #define transport_class_to_conn(_cdev) \
216 	iscsi_dev_to_conn(_cdev->parent)
217 
218 #define iscsi_conn_to_session(_conn) \
219 	iscsi_dev_to_session(_conn->dev.parent)
220 
221 /* iscsi class session state */
222 enum {
223 	ISCSI_SESSION_LOGGED_IN,
224 	ISCSI_SESSION_FAILED,
225 	ISCSI_SESSION_FREE,
226 };
227 
228 #define ISCSI_MAX_TARGET -1
229 
230 struct iscsi_cls_session {
231 	struct list_head sess_list;		/* item in session_list */
232 	struct iscsi_transport *transport;
233 	spinlock_t lock;
234 	struct work_struct block_work;
235 	struct work_struct unblock_work;
236 	struct work_struct scan_work;
237 	struct work_struct unbind_work;
238 
239 	/* recovery fields */
240 	int recovery_tmo;
241 	struct delayed_work recovery_work;
242 
243 	unsigned int target_id;
244 	bool ida_used;
245 
246 	/*
247 	 * pid of userspace process that created session or -1 if
248 	 * created by the kernel.
249 	 */
250 	pid_t creator;
251 	int state;
252 	int sid;				/* session id */
253 	void *dd_data;				/* LLD private data */
254 	struct device dev;	/* sysfs transport/container device */
255 };
256 
257 #define iscsi_dev_to_session(_dev) \
258 	container_of(_dev, struct iscsi_cls_session, dev)
259 
260 #define transport_class_to_session(_cdev) \
261 	iscsi_dev_to_session(_cdev->parent)
262 
263 #define iscsi_session_to_shost(_session) \
264 	dev_to_shost(_session->dev.parent)
265 
266 #define starget_to_session(_stgt) \
267 	iscsi_dev_to_session(_stgt->dev.parent)
268 
269 struct iscsi_cls_host {
270 	atomic_t nr_scans;
271 	struct mutex mutex;
272 	struct request_queue *bsg_q;
273 	uint32_t port_speed;
274 	uint32_t port_state;
275 };
276 
277 #define iscsi_job_to_shost(_job) \
278         dev_to_shost(_job->dev)
279 
280 extern void iscsi_host_for_each_session(struct Scsi_Host *shost,
281 				void (*fn)(struct iscsi_cls_session *));
282 
283 struct iscsi_endpoint {
284 	void *dd_data;			/* LLD private data */
285 	struct device dev;
286 	uint64_t id;
287 	struct iscsi_cls_conn *conn;
288 };
289 
290 struct iscsi_iface {
291 	struct device dev;
292 	struct iscsi_transport *transport;
293 	uint32_t iface_type;	/* IPv4 or IPv6 */
294 	uint32_t iface_num;	/* iface number, 0 - n */
295 	void *dd_data;		/* LLD private data */
296 };
297 
298 #define iscsi_dev_to_iface(_dev) \
299 	container_of(_dev, struct iscsi_iface, dev)
300 
301 #define iscsi_iface_to_shost(_iface) \
302 	dev_to_shost(_iface->dev.parent)
303 
304 
305 struct iscsi_bus_flash_conn {
306 	struct list_head conn_list;	/* item in connlist */
307 	void *dd_data;			/* LLD private data */
308 	struct iscsi_transport *transport;
309 	struct device dev;		/* sysfs transport/container device */
310 	/* iscsi connection parameters */
311 	uint32_t		exp_statsn;
312 	uint32_t		statsn;
313 	unsigned		max_recv_dlength; /* initiator_max_recv_dsl*/
314 	unsigned		max_xmit_dlength; /* target_max_recv_dsl */
315 	unsigned		max_segment_size;
316 	unsigned		tcp_xmit_wsf;
317 	unsigned		tcp_recv_wsf;
318 	int			hdrdgst_en;
319 	int			datadgst_en;
320 	int			port;
321 	char			*ipaddress;
322 	char			*link_local_ipv6_addr;
323 	char			*redirect_ipaddr;
324 	uint16_t		keepalive_timeout;
325 	uint16_t		local_port;
326 	uint8_t			snack_req_en;
327 	/* tcp timestamp negotiation status */
328 	uint8_t			tcp_timestamp_stat;
329 	uint8_t			tcp_nagle_disable;
330 	/* tcp window scale factor */
331 	uint8_t			tcp_wsf_disable;
332 	uint8_t			tcp_timer_scale;
333 	uint8_t			tcp_timestamp_en;
334 	uint8_t			ipv4_tos;
335 	uint8_t			ipv6_traffic_class;
336 	uint8_t			ipv6_flow_label;
337 	uint8_t			fragment_disable;
338 	/* Link local IPv6 address is assigned by firmware or driver */
339 	uint8_t			is_fw_assigned_ipv6;
340 };
341 
342 #define iscsi_dev_to_flash_conn(_dev) \
343 	container_of(_dev, struct iscsi_bus_flash_conn, dev)
344 
345 #define iscsi_flash_conn_to_flash_session(_conn) \
346 	iscsi_dev_to_flash_session(_conn->dev.parent)
347 
348 #define ISID_SIZE 6
349 
350 struct iscsi_bus_flash_session {
351 	struct list_head sess_list;		/* item in session_list */
352 	struct iscsi_transport *transport;
353 	unsigned int target_id;
354 	int flash_state;	/* persistent or non-persistent */
355 	void *dd_data;				/* LLD private data */
356 	struct device dev;	/* sysfs transport/container device */
357 	/* iscsi session parameters */
358 	unsigned		first_burst;
359 	unsigned		max_burst;
360 	unsigned short		max_r2t;
361 	int			default_taskmgmt_timeout;
362 	int			initial_r2t_en;
363 	int			imm_data_en;
364 	int			time2wait;
365 	int			time2retain;
366 	int			pdu_inorder_en;
367 	int			dataseq_inorder_en;
368 	int			erl;
369 	int			tpgt;
370 	char			*username;
371 	char			*username_in;
372 	char			*password;
373 	char			*password_in;
374 	char			*targetname;
375 	char			*targetalias;
376 	char			*portal_type;
377 	uint16_t		tsid;
378 	uint16_t		chap_in_idx;
379 	uint16_t		chap_out_idx;
380 	/* index of iSCSI discovery session if the entry is
381 	 * discovered by iSCSI discovery session
382 	 */
383 	uint16_t		discovery_parent_idx;
384 	/* indicates if discovery was done through iSNS discovery service
385 	 * or through sendTarget */
386 	uint16_t		discovery_parent_type;
387 	/* Firmware auto sendtarget discovery disable */
388 	uint8_t			auto_snd_tgt_disable;
389 	uint8_t			discovery_sess;
390 	/* indicates if this flashnode entry is enabled or disabled */
391 	uint8_t			entry_state;
392 	uint8_t			chap_auth_en;
393 	/* enables firmware to auto logout the discovery session on discovery
394 	 * completion
395 	 */
396 	uint8_t			discovery_logout_en;
397 	uint8_t			bidi_chap_en;
398 	/* makes authentication for discovery session optional */
399 	uint8_t			discovery_auth_optional;
400 	uint8_t			isid[ISID_SIZE];
401 	uint8_t			is_boot_target;
402 };
403 
404 #define iscsi_dev_to_flash_session(_dev) \
405 	container_of(_dev, struct iscsi_bus_flash_session, dev)
406 
407 #define iscsi_flash_session_to_shost(_session) \
408 	dev_to_shost(_session->dev.parent)
409 
410 /*
411  * session and connection functions that can be used by HW iSCSI LLDs
412  */
413 #define iscsi_cls_session_printk(prefix, _cls_session, fmt, a...) \
414 	dev_printk(prefix, &(_cls_session)->dev, fmt, ##a)
415 
416 #define iscsi_cls_conn_printk(prefix, _cls_conn, fmt, a...) \
417 	dev_printk(prefix, &(_cls_conn)->dev, fmt, ##a)
418 
419 extern int iscsi_session_chkready(struct iscsi_cls_session *session);
420 extern int iscsi_is_session_online(struct iscsi_cls_session *session);
421 extern struct iscsi_cls_session *iscsi_alloc_session(struct Scsi_Host *shost,
422 				struct iscsi_transport *transport, int dd_size);
423 extern int iscsi_add_session(struct iscsi_cls_session *session,
424 			     unsigned int target_id);
425 extern int iscsi_session_event(struct iscsi_cls_session *session,
426 			       enum iscsi_uevent_e event);
427 extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
428 						struct iscsi_transport *t,
429 						int dd_size,
430 						unsigned int target_id);
431 extern void iscsi_remove_session(struct iscsi_cls_session *session);
432 extern void iscsi_free_session(struct iscsi_cls_session *session);
433 extern int iscsi_destroy_session(struct iscsi_cls_session *session);
434 extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
435 						int dd_size, uint32_t cid);
436 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
437 extern void iscsi_unblock_session(struct iscsi_cls_session *session);
438 extern void iscsi_block_session(struct iscsi_cls_session *session);
439 extern int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time);
440 extern struct iscsi_endpoint *iscsi_create_endpoint(int dd_size);
441 extern void iscsi_destroy_endpoint(struct iscsi_endpoint *ep);
442 extern struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle);
443 extern int iscsi_block_scsi_eh(struct scsi_cmnd *cmd);
444 extern struct iscsi_iface *iscsi_create_iface(struct Scsi_Host *shost,
445 					      struct iscsi_transport *t,
446 					      uint32_t iface_type,
447 					      uint32_t iface_num, int dd_size);
448 extern void iscsi_destroy_iface(struct iscsi_iface *iface);
449 extern struct iscsi_iface *iscsi_lookup_iface(int handle);
450 extern char *iscsi_get_port_speed_name(struct Scsi_Host *shost);
451 extern char *iscsi_get_port_state_name(struct Scsi_Host *shost);
452 extern int iscsi_is_session_dev(const struct device *dev);
453 
454 extern char *iscsi_get_discovery_parent_name(int parent_type);
455 extern struct device *
456 iscsi_find_flashnode(struct Scsi_Host *shost, void *data,
457 		     int (*fn)(struct device *dev, void *data));
458 
459 extern struct iscsi_bus_flash_session *
460 iscsi_create_flashnode_sess(struct Scsi_Host *shost, int index,
461 			    struct iscsi_transport *transport, int dd_size);
462 
463 extern struct iscsi_bus_flash_conn *
464 iscsi_create_flashnode_conn(struct Scsi_Host *shost,
465 			    struct iscsi_bus_flash_session *fnode_sess,
466 			    struct iscsi_transport *transport, int dd_size);
467 
468 extern void
469 iscsi_destroy_flashnode_sess(struct iscsi_bus_flash_session *fnode_sess);
470 
471 extern void iscsi_destroy_all_flashnode(struct Scsi_Host *shost);
472 extern int iscsi_flashnode_bus_match(struct device *dev,
473 				     struct device_driver *drv);
474 extern struct device *
475 iscsi_find_flashnode_sess(struct Scsi_Host *shost, void *data,
476 			  int (*fn)(struct device *dev, void *data));
477 extern struct device *
478 iscsi_find_flashnode_conn(struct iscsi_bus_flash_session *fnode_sess);
479 
480 #endif
481