1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * iSCSI transport class definitions
4  *
5  * Copyright (C) IBM Corporation, 2004
6  * Copyright (C) Mike Christie, 2004 - 2006
7  * Copyright (C) Dmitry Yusupov, 2004 - 2005
8  * Copyright (C) Alex Aizman, 2004 - 2005
9  */
10 #ifndef SCSI_TRANSPORT_ISCSI_H
11 #define SCSI_TRANSPORT_ISCSI_H
12 
13 #include <linux/device.h>
14 #include <linux/list.h>
15 #include <linux/mutex.h>
16 #include <scsi/iscsi_if.h>
17 
18 struct scsi_transport_template;
19 struct iscsi_transport;
20 struct iscsi_endpoint;
21 struct Scsi_Host;
22 struct scsi_cmnd;
23 struct iscsi_cls_conn;
24 struct iscsi_conn;
25 struct iscsi_task;
26 struct sockaddr;
27 struct iscsi_iface;
28 struct bsg_job;
29 struct iscsi_bus_flash_session;
30 struct iscsi_bus_flash_conn;
31 
32 /**
33  * struct iscsi_transport - iSCSI Transport template
34  *
35  * @name:		transport name
36  * @caps:		iSCSI Data-Path capabilities
37  * @create_session:	create new iSCSI session object
38  * @destroy_session:	destroy existing iSCSI session object
39  * @create_conn:	create new iSCSI connection
40  * @bind_conn:		associate this connection with existing iSCSI session
41  *			and specified transport descriptor
42  * @destroy_conn:	destroy inactive iSCSI connection
43  * @set_param:		set iSCSI parameter. Return 0 on success, -ENODATA
44  *			when param is not supported, and a -Exx value on other
45  *			error.
46  * @get_param		get iSCSI parameter. Must return number of bytes
47  *			copied to buffer on success, -ENODATA when param
48  *			is not supported, and a -Exx value on other error
49  * @start_conn:		set connection to be operational
50  * @stop_conn:		suspend/recover/terminate connection
51  * @send_pdu:		send iSCSI PDU, Login, Logout, NOP-Out, Reject, Text.
52  * @session_recovery_timedout: notify LLD a block during recovery timed out
53  * @init_task:		Initialize a iscsi_task and any internal structs.
54  *			When offloading the data path, this is called from
55  *			queuecommand with the session lock, or from the
56  *			iscsi_conn_send_pdu context with the session lock.
57  *			When not offloading the data path, this is called
58  *			from the scsi work queue without the session lock.
59  * @xmit_task		Requests LLD to transfer cmd task. Returns 0 or the
60  *			number of bytes transferred on success, and -Exyz
61  *			value on error. When offloading the data path, this
62  *			is called from queuecommand with the session lock, or
63  *			from the iscsi_conn_send_pdu context with the session
64  *			lock. When not offloading the data path, this is called
65  *			from the scsi work queue without the session lock.
66  * @cleanup_task:	requests LLD to fail task. Called with session lock
67  *			and after the connection has been suspended and
68  *			terminated during recovery. If called
69  *			from abort task then connection is not suspended
70  *			or terminated but sk_callback_lock is held
71  *
72  * Template API provided by iSCSI Transport
73  */
74 struct iscsi_transport {
75 	struct module *owner;
76 	char *name;
77 	unsigned int caps;
78 
79 	struct iscsi_cls_session *(*create_session) (struct iscsi_endpoint *ep,
80 					uint16_t cmds_max, uint16_t qdepth,
81 					uint32_t sn);
82 	void (*destroy_session) (struct iscsi_cls_session *session);
83 	struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess,
84 				uint32_t cid);
85 	int (*bind_conn) (struct iscsi_cls_session *session,
86 			  struct iscsi_cls_conn *cls_conn,
87 			  uint64_t transport_eph, int is_leading);
88 	int (*start_conn) (struct iscsi_cls_conn *conn);
89 	void (*stop_conn) (struct iscsi_cls_conn *conn, int flag);
90 	void (*destroy_conn) (struct iscsi_cls_conn *conn);
91 	int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param,
92 			  char *buf, int buflen);
93 	int (*get_ep_param) (struct iscsi_endpoint *ep, enum iscsi_param param,
94 			     char *buf);
95 	int (*get_conn_param) (struct iscsi_cls_conn *conn,
96 			       enum iscsi_param param, char *buf);
97 	int (*get_session_param) (struct iscsi_cls_session *session,
98 				  enum iscsi_param param, char *buf);
99 	int (*get_host_param) (struct Scsi_Host *shost,
100 				enum iscsi_host_param param, char *buf);
101 	int (*set_host_param) (struct Scsi_Host *shost,
102 			       enum iscsi_host_param param, char *buf,
103 			       int buflen);
104 	int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
105 			 char *data, uint32_t data_size);
106 	void (*get_stats) (struct iscsi_cls_conn *conn,
107 			   struct iscsi_stats *stats);
108 
109 	int (*init_task) (struct iscsi_task *task);
110 	int (*xmit_task) (struct iscsi_task *task);
111 	void (*cleanup_task) (struct iscsi_task *task);
112 
113 	int (*alloc_pdu) (struct iscsi_task *task, uint8_t opcode);
114 	int (*xmit_pdu) (struct iscsi_task *task);
115 	int (*init_pdu) (struct iscsi_task *task, unsigned int offset,
116 			 unsigned int count);
117 	void (*parse_pdu_itt) (struct iscsi_conn *conn, itt_t itt,
118 			       int *index, int *age);
119 
120 	void (*session_recovery_timedout) (struct iscsi_cls_session *session);
121 	struct iscsi_endpoint *(*ep_connect) (struct Scsi_Host *shost,
122 					      struct sockaddr *dst_addr,
123 					      int non_blocking);
124 	int (*ep_poll) (struct iscsi_endpoint *ep, int timeout_ms);
125 	void (*ep_disconnect) (struct iscsi_endpoint *ep);
126 	int (*tgt_dscvr) (struct Scsi_Host *shost, enum iscsi_tgt_dscvr type,
127 			  uint32_t enable, struct sockaddr *dst_addr);
128 	int (*set_path) (struct Scsi_Host *shost, struct iscsi_path *params);
129 	int (*set_iface_param) (struct Scsi_Host *shost, void *data,
130 				uint32_t len);
131 	int (*get_iface_param) (struct iscsi_iface *iface,
132 				enum iscsi_param_type param_type,
133 				int param, char *buf);
134 	umode_t (*attr_is_visible)(int param_type, int param);
135 	int (*bsg_request)(struct bsg_job *job);
136 	int (*send_ping) (struct Scsi_Host *shost, uint32_t iface_num,
137 			  uint32_t iface_type, uint32_t payload_size,
138 			  uint32_t pid, struct sockaddr *dst_addr);
139 	int (*get_chap) (struct Scsi_Host *shost, uint16_t chap_tbl_idx,
140 			 uint32_t *num_entries, char *buf);
141 	int (*delete_chap) (struct Scsi_Host *shost, uint16_t chap_tbl_idx);
142 	int (*set_chap) (struct Scsi_Host *shost, void *data, int len);
143 	int (*get_flashnode_param) (struct iscsi_bus_flash_session *fnode_sess,
144 				    int param, char *buf);
145 	int (*set_flashnode_param) (struct iscsi_bus_flash_session *fnode_sess,
146 				    struct iscsi_bus_flash_conn *fnode_conn,
147 				    void *data, int len);
148 	int (*new_flashnode) (struct Scsi_Host *shost, const char *buf,
149 			      int len);
150 	int (*del_flashnode) (struct iscsi_bus_flash_session *fnode_sess);
151 	int (*login_flashnode) (struct iscsi_bus_flash_session *fnode_sess,
152 				struct iscsi_bus_flash_conn *fnode_conn);
153 	int (*logout_flashnode) (struct iscsi_bus_flash_session *fnode_sess,
154 				 struct iscsi_bus_flash_conn *fnode_conn);
155 	int (*logout_flashnode_sid) (struct iscsi_cls_session *cls_sess);
156 	int (*get_host_stats) (struct Scsi_Host *shost, char *buf, int len);
157 	u8 (*check_protection)(struct iscsi_task *task, sector_t *sector);
158 };
159 
160 /*
161  * transport registration upcalls
162  */
163 extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt);
164 extern int iscsi_unregister_transport(struct iscsi_transport *tt);
165 
166 /*
167  * control plane upcalls
168  */
169 extern void iscsi_conn_error_event(struct iscsi_cls_conn *conn,
170 				   enum iscsi_err error);
171 extern void iscsi_conn_login_event(struct iscsi_cls_conn *conn,
172 				   enum iscsi_conn_state state);
173 extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
174 			  char *data, uint32_t data_size);
175 
176 extern int iscsi_offload_mesg(struct Scsi_Host *shost,
177 			      struct iscsi_transport *transport, uint32_t type,
178 			      char *data, uint16_t data_size);
179 
180 extern void iscsi_post_host_event(uint32_t host_no,
181 				  struct iscsi_transport *transport,
182 				  enum iscsi_host_event_code code,
183 				  uint32_t data_size,
184 				  uint8_t *data);
185 
186 extern void iscsi_ping_comp_event(uint32_t host_no,
187 				  struct iscsi_transport *transport,
188 				  uint32_t status, uint32_t pid,
189 				  uint32_t data_size, uint8_t *data);
190 
191 /* iscsi class connection state */
192 enum iscsi_connection_state {
193 	ISCSI_CONN_UP = 0,
194 	ISCSI_CONN_DOWN,
195 	ISCSI_CONN_FAILED,
196 };
197 
198 struct iscsi_cls_conn {
199 	struct list_head conn_list;	/* item in connlist */
200 	struct list_head conn_list_err;	/* item in connlist_err */
201 	void *dd_data;			/* LLD private data */
202 	struct iscsi_transport *transport;
203 	uint32_t cid;			/* connection id */
204 	struct mutex ep_mutex;
205 	struct iscsi_endpoint *ep;
206 
207 	struct device dev;		/* sysfs transport/container device */
208 	enum iscsi_connection_state state;
209 };
210 
211 #define iscsi_dev_to_conn(_dev) \
212 	container_of(_dev, struct iscsi_cls_conn, dev)
213 
214 #define transport_class_to_conn(_cdev) \
215 	iscsi_dev_to_conn(_cdev->parent)
216 
217 #define iscsi_conn_to_session(_conn) \
218 	iscsi_dev_to_session(_conn->dev.parent)
219 
220 /* iscsi class session state */
221 enum {
222 	ISCSI_SESSION_LOGGED_IN,
223 	ISCSI_SESSION_FAILED,
224 	ISCSI_SESSION_FREE,
225 };
226 
227 #define ISCSI_MAX_TARGET -1
228 
229 struct iscsi_cls_session {
230 	struct list_head sess_list;		/* item in session_list */
231 	struct iscsi_transport *transport;
232 	spinlock_t lock;
233 	struct work_struct block_work;
234 	struct work_struct unblock_work;
235 	struct work_struct scan_work;
236 	struct work_struct unbind_work;
237 	struct work_struct destroy_work;
238 
239 	/* recovery fields */
240 	int recovery_tmo;
241 	bool recovery_tmo_sysfs_override;
242 	struct delayed_work recovery_work;
243 
244 	unsigned int target_id;
245 	bool ida_used;
246 
247 	/*
248 	 * pid of userspace process that created session or -1 if
249 	 * created by the kernel.
250 	 */
251 	pid_t creator;
252 	int state;
253 	int sid;				/* session id */
254 	void *dd_data;				/* LLD private data */
255 	struct device dev;	/* sysfs transport/container device */
256 };
257 
258 #define iscsi_dev_to_session(_dev) \
259 	container_of(_dev, struct iscsi_cls_session, dev)
260 
261 #define transport_class_to_session(_cdev) \
262 	iscsi_dev_to_session(_cdev->parent)
263 
264 #define iscsi_session_to_shost(_session) \
265 	dev_to_shost(_session->dev.parent)
266 
267 #define starget_to_session(_stgt) \
268 	iscsi_dev_to_session(_stgt->dev.parent)
269 
270 struct iscsi_cls_host {
271 	atomic_t nr_scans;
272 	struct mutex mutex;
273 	struct request_queue *bsg_q;
274 	uint32_t port_speed;
275 	uint32_t port_state;
276 };
277 
278 #define iscsi_job_to_shost(_job) \
279         dev_to_shost(_job->dev)
280 
281 extern void iscsi_host_for_each_session(struct Scsi_Host *shost,
282 				void (*fn)(struct iscsi_cls_session *));
283 
284 struct iscsi_endpoint {
285 	void *dd_data;			/* LLD private data */
286 	struct device dev;
287 	uint64_t id;
288 	struct iscsi_cls_conn *conn;
289 };
290 
291 struct iscsi_iface {
292 	struct device dev;
293 	struct iscsi_transport *transport;
294 	uint32_t iface_type;	/* IPv4 or IPv6 */
295 	uint32_t iface_num;	/* iface number, 0 - n */
296 	void *dd_data;		/* LLD private data */
297 };
298 
299 #define iscsi_dev_to_iface(_dev) \
300 	container_of(_dev, struct iscsi_iface, dev)
301 
302 #define iscsi_iface_to_shost(_iface) \
303 	dev_to_shost(_iface->dev.parent)
304 
305 
306 struct iscsi_bus_flash_conn {
307 	struct list_head conn_list;	/* item in connlist */
308 	void *dd_data;			/* LLD private data */
309 	struct iscsi_transport *transport;
310 	struct device dev;		/* sysfs transport/container device */
311 	/* iscsi connection parameters */
312 	uint32_t		exp_statsn;
313 	uint32_t		statsn;
314 	unsigned		max_recv_dlength; /* initiator_max_recv_dsl*/
315 	unsigned		max_xmit_dlength; /* target_max_recv_dsl */
316 	unsigned		max_segment_size;
317 	unsigned		tcp_xmit_wsf;
318 	unsigned		tcp_recv_wsf;
319 	int			hdrdgst_en;
320 	int			datadgst_en;
321 	int			port;
322 	char			*ipaddress;
323 	char			*link_local_ipv6_addr;
324 	char			*redirect_ipaddr;
325 	uint16_t		keepalive_timeout;
326 	uint16_t		local_port;
327 	uint8_t			snack_req_en;
328 	/* tcp timestamp negotiation status */
329 	uint8_t			tcp_timestamp_stat;
330 	uint8_t			tcp_nagle_disable;
331 	/* tcp window scale factor */
332 	uint8_t			tcp_wsf_disable;
333 	uint8_t			tcp_timer_scale;
334 	uint8_t			tcp_timestamp_en;
335 	uint8_t			ipv4_tos;
336 	uint8_t			ipv6_traffic_class;
337 	uint8_t			ipv6_flow_label;
338 	uint8_t			fragment_disable;
339 	/* Link local IPv6 address is assigned by firmware or driver */
340 	uint8_t			is_fw_assigned_ipv6;
341 };
342 
343 #define iscsi_dev_to_flash_conn(_dev) \
344 	container_of(_dev, struct iscsi_bus_flash_conn, dev)
345 
346 #define iscsi_flash_conn_to_flash_session(_conn) \
347 	iscsi_dev_to_flash_session(_conn->dev.parent)
348 
349 #define ISID_SIZE 6
350 
351 struct iscsi_bus_flash_session {
352 	struct list_head sess_list;		/* item in session_list */
353 	struct iscsi_transport *transport;
354 	unsigned int target_id;
355 	int flash_state;	/* persistent or non-persistent */
356 	void *dd_data;				/* LLD private data */
357 	struct device dev;	/* sysfs transport/container device */
358 	/* iscsi session parameters */
359 	unsigned		first_burst;
360 	unsigned		max_burst;
361 	unsigned short		max_r2t;
362 	int			default_taskmgmt_timeout;
363 	int			initial_r2t_en;
364 	int			imm_data_en;
365 	int			time2wait;
366 	int			time2retain;
367 	int			pdu_inorder_en;
368 	int			dataseq_inorder_en;
369 	int			erl;
370 	int			tpgt;
371 	char			*username;
372 	char			*username_in;
373 	char			*password;
374 	char			*password_in;
375 	char			*targetname;
376 	char			*targetalias;
377 	char			*portal_type;
378 	uint16_t		tsid;
379 	uint16_t		chap_in_idx;
380 	uint16_t		chap_out_idx;
381 	/* index of iSCSI discovery session if the entry is
382 	 * discovered by iSCSI discovery session
383 	 */
384 	uint16_t		discovery_parent_idx;
385 	/* indicates if discovery was done through iSNS discovery service
386 	 * or through sendTarget */
387 	uint16_t		discovery_parent_type;
388 	/* Firmware auto sendtarget discovery disable */
389 	uint8_t			auto_snd_tgt_disable;
390 	uint8_t			discovery_sess;
391 	/* indicates if this flashnode entry is enabled or disabled */
392 	uint8_t			entry_state;
393 	uint8_t			chap_auth_en;
394 	/* enables firmware to auto logout the discovery session on discovery
395 	 * completion
396 	 */
397 	uint8_t			discovery_logout_en;
398 	uint8_t			bidi_chap_en;
399 	/* makes authentication for discovery session optional */
400 	uint8_t			discovery_auth_optional;
401 	uint8_t			isid[ISID_SIZE];
402 	uint8_t			is_boot_target;
403 };
404 
405 #define iscsi_dev_to_flash_session(_dev) \
406 	container_of(_dev, struct iscsi_bus_flash_session, dev)
407 
408 #define iscsi_flash_session_to_shost(_session) \
409 	dev_to_shost(_session->dev.parent)
410 
411 /*
412  * session and connection functions that can be used by HW iSCSI LLDs
413  */
414 #define iscsi_cls_session_printk(prefix, _cls_session, fmt, a...) \
415 	dev_printk(prefix, &(_cls_session)->dev, fmt, ##a)
416 
417 #define iscsi_cls_conn_printk(prefix, _cls_conn, fmt, a...) \
418 	dev_printk(prefix, &(_cls_conn)->dev, fmt, ##a)
419 
420 extern int iscsi_session_chkready(struct iscsi_cls_session *session);
421 extern int iscsi_is_session_online(struct iscsi_cls_session *session);
422 extern struct iscsi_cls_session *iscsi_alloc_session(struct Scsi_Host *shost,
423 				struct iscsi_transport *transport, int dd_size);
424 extern int iscsi_add_session(struct iscsi_cls_session *session,
425 			     unsigned int target_id);
426 extern int iscsi_session_event(struct iscsi_cls_session *session,
427 			       enum iscsi_uevent_e event);
428 extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
429 						struct iscsi_transport *t,
430 						int dd_size,
431 						unsigned int target_id);
432 extern void iscsi_remove_session(struct iscsi_cls_session *session);
433 extern void iscsi_free_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 extern char *
481 iscsi_get_ipaddress_state_name(enum iscsi_ipaddress_state port_state);
482 extern char *iscsi_get_router_state_name(enum iscsi_router_state router_state);
483 #endif
484