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 	void (*unbind_conn) (struct iscsi_cls_conn *conn, bool is_active);
86 	int (*bind_conn) (struct iscsi_cls_session *session,
87 			  struct iscsi_cls_conn *cls_conn,
88 			  uint64_t transport_eph, int is_leading);
89 	int (*start_conn) (struct iscsi_cls_conn *conn);
90 	void (*stop_conn) (struct iscsi_cls_conn *conn, int flag);
91 	void (*destroy_conn) (struct iscsi_cls_conn *conn);
92 	int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param,
93 			  char *buf, int buflen);
94 	int (*get_ep_param) (struct iscsi_endpoint *ep, enum iscsi_param param,
95 			     char *buf);
96 	int (*get_conn_param) (struct iscsi_cls_conn *conn,
97 			       enum iscsi_param param, char *buf);
98 	int (*get_session_param) (struct iscsi_cls_session *session,
99 				  enum iscsi_param param, char *buf);
100 	int (*get_host_param) (struct Scsi_Host *shost,
101 				enum iscsi_host_param param, char *buf);
102 	int (*set_host_param) (struct Scsi_Host *shost,
103 			       enum iscsi_host_param param, char *buf,
104 			       int buflen);
105 	int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
106 			 char *data, uint32_t data_size);
107 	void (*get_stats) (struct iscsi_cls_conn *conn,
108 			   struct iscsi_stats *stats);
109 
110 	int (*init_task) (struct iscsi_task *task);
111 	int (*xmit_task) (struct iscsi_task *task);
112 	void (*cleanup_task) (struct iscsi_task *task);
113 
114 	int (*alloc_pdu) (struct iscsi_task *task, uint8_t opcode);
115 	int (*xmit_pdu) (struct iscsi_task *task);
116 	int (*init_pdu) (struct iscsi_task *task, unsigned int offset,
117 			 unsigned int count);
118 	void (*parse_pdu_itt) (struct iscsi_conn *conn, itt_t itt,
119 			       int *index, int *age);
120 
121 	void (*session_recovery_timedout) (struct iscsi_cls_session *session);
122 	struct iscsi_endpoint *(*ep_connect) (struct Scsi_Host *shost,
123 					      struct sockaddr *dst_addr,
124 					      int non_blocking);
125 	int (*ep_poll) (struct iscsi_endpoint *ep, int timeout_ms);
126 	void (*ep_disconnect) (struct iscsi_endpoint *ep);
127 	int (*tgt_dscvr) (struct Scsi_Host *shost, enum iscsi_tgt_dscvr type,
128 			  uint32_t enable, struct sockaddr *dst_addr);
129 	int (*set_path) (struct Scsi_Host *shost, struct iscsi_path *params);
130 	int (*set_iface_param) (struct Scsi_Host *shost, void *data,
131 				uint32_t len);
132 	int (*get_iface_param) (struct iscsi_iface *iface,
133 				enum iscsi_param_type param_type,
134 				int param, char *buf);
135 	umode_t (*attr_is_visible)(int param_type, int param);
136 	int (*bsg_request)(struct bsg_job *job);
137 	int (*send_ping) (struct Scsi_Host *shost, uint32_t iface_num,
138 			  uint32_t iface_type, uint32_t payload_size,
139 			  uint32_t pid, struct sockaddr *dst_addr);
140 	int (*get_chap) (struct Scsi_Host *shost, uint16_t chap_tbl_idx,
141 			 uint32_t *num_entries, char *buf);
142 	int (*delete_chap) (struct Scsi_Host *shost, uint16_t chap_tbl_idx);
143 	int (*set_chap) (struct Scsi_Host *shost, void *data, int len);
144 	int (*get_flashnode_param) (struct iscsi_bus_flash_session *fnode_sess,
145 				    int param, char *buf);
146 	int (*set_flashnode_param) (struct iscsi_bus_flash_session *fnode_sess,
147 				    struct iscsi_bus_flash_conn *fnode_conn,
148 				    void *data, int len);
149 	int (*new_flashnode) (struct Scsi_Host *shost, const char *buf,
150 			      int len);
151 	int (*del_flashnode) (struct iscsi_bus_flash_session *fnode_sess);
152 	int (*login_flashnode) (struct iscsi_bus_flash_session *fnode_sess,
153 				struct iscsi_bus_flash_conn *fnode_conn);
154 	int (*logout_flashnode) (struct iscsi_bus_flash_session *fnode_sess,
155 				 struct iscsi_bus_flash_conn *fnode_conn);
156 	int (*logout_flashnode_sid) (struct iscsi_cls_session *cls_sess);
157 	int (*get_host_stats) (struct Scsi_Host *shost, char *buf, int len);
158 	u8 (*check_protection)(struct iscsi_task *task, sector_t *sector);
159 };
160 
161 /*
162  * transport registration upcalls
163  */
164 extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt);
165 extern int iscsi_unregister_transport(struct iscsi_transport *tt);
166 
167 /*
168  * control plane upcalls
169  */
170 extern void iscsi_conn_error_event(struct iscsi_cls_conn *conn,
171 				   enum iscsi_err error);
172 extern void iscsi_conn_login_event(struct iscsi_cls_conn *conn,
173 				   enum iscsi_conn_state state);
174 extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
175 			  char *data, uint32_t data_size);
176 
177 extern int iscsi_offload_mesg(struct Scsi_Host *shost,
178 			      struct iscsi_transport *transport, uint32_t type,
179 			      char *data, uint16_t data_size);
180 
181 extern void iscsi_post_host_event(uint32_t host_no,
182 				  struct iscsi_transport *transport,
183 				  enum iscsi_host_event_code code,
184 				  uint32_t data_size,
185 				  uint8_t *data);
186 
187 extern void iscsi_ping_comp_event(uint32_t host_no,
188 				  struct iscsi_transport *transport,
189 				  uint32_t status, uint32_t pid,
190 				  uint32_t data_size, uint8_t *data);
191 
192 /* iscsi class connection state */
193 enum iscsi_connection_state {
194 	ISCSI_CONN_UP = 0,
195 	ISCSI_CONN_DOWN,
196 	ISCSI_CONN_FAILED,
197 	ISCSI_CONN_BOUND,
198 };
199 
200 #define ISCSI_CLS_CONN_BIT_CLEANUP	1
201 
202 struct iscsi_cls_conn {
203 	struct list_head conn_list;	/* item in connlist */
204 	void *dd_data;			/* LLD private data */
205 	struct iscsi_transport *transport;
206 	uint32_t cid;			/* connection id */
207 	/*
208 	 * This protects the conn startup and binding/unbinding of the ep to
209 	 * the conn. Unbinding includes ep_disconnect and stop_conn.
210 	 */
211 	struct mutex ep_mutex;
212 	struct iscsi_endpoint *ep;
213 
214 	unsigned long flags;
215 	struct work_struct cleanup_work;
216 
217 	struct device dev;		/* sysfs transport/container device */
218 	enum iscsi_connection_state state;
219 };
220 
221 #define iscsi_dev_to_conn(_dev) \
222 	container_of(_dev, struct iscsi_cls_conn, dev)
223 
224 #define transport_class_to_conn(_cdev) \
225 	iscsi_dev_to_conn(_cdev->parent)
226 
227 #define iscsi_conn_to_session(_conn) \
228 	iscsi_dev_to_session(_conn->dev.parent)
229 
230 /* iscsi class session state */
231 enum {
232 	ISCSI_SESSION_LOGGED_IN,
233 	ISCSI_SESSION_FAILED,
234 	ISCSI_SESSION_FREE,
235 };
236 
237 #define ISCSI_MAX_TARGET -1
238 
239 struct iscsi_cls_session {
240 	struct list_head sess_list;		/* item in session_list */
241 	struct iscsi_transport *transport;
242 	spinlock_t lock;
243 	struct work_struct block_work;
244 	struct work_struct unblock_work;
245 	struct work_struct scan_work;
246 	struct work_struct unbind_work;
247 	struct work_struct destroy_work;
248 
249 	/* recovery fields */
250 	int recovery_tmo;
251 	bool recovery_tmo_sysfs_override;
252 	struct delayed_work recovery_work;
253 
254 	unsigned int target_id;
255 	bool ida_used;
256 
257 	/*
258 	 * pid of userspace process that created session or -1 if
259 	 * created by the kernel.
260 	 */
261 	pid_t creator;
262 	int state;
263 	int sid;				/* session id */
264 	void *dd_data;				/* LLD private data */
265 	struct device dev;	/* sysfs transport/container device */
266 };
267 
268 #define iscsi_dev_to_session(_dev) \
269 	container_of(_dev, struct iscsi_cls_session, dev)
270 
271 #define transport_class_to_session(_cdev) \
272 	iscsi_dev_to_session(_cdev->parent)
273 
274 #define iscsi_session_to_shost(_session) \
275 	dev_to_shost(_session->dev.parent)
276 
277 #define starget_to_session(_stgt) \
278 	iscsi_dev_to_session(_stgt->dev.parent)
279 
280 struct iscsi_cls_host {
281 	atomic_t nr_scans;
282 	struct mutex mutex;
283 	struct request_queue *bsg_q;
284 	uint32_t port_speed;
285 	uint32_t port_state;
286 };
287 
288 #define iscsi_job_to_shost(_job) \
289         dev_to_shost(_job->dev)
290 
291 extern void iscsi_host_for_each_session(struct Scsi_Host *shost,
292 				void (*fn)(struct iscsi_cls_session *));
293 
294 struct iscsi_endpoint {
295 	void *dd_data;			/* LLD private data */
296 	struct device dev;
297 	uint64_t id;
298 	struct iscsi_cls_conn *conn;
299 };
300 
301 struct iscsi_iface {
302 	struct device dev;
303 	struct iscsi_transport *transport;
304 	uint32_t iface_type;	/* IPv4 or IPv6 */
305 	uint32_t iface_num;	/* iface number, 0 - n */
306 	void *dd_data;		/* LLD private data */
307 };
308 
309 #define iscsi_dev_to_iface(_dev) \
310 	container_of(_dev, struct iscsi_iface, dev)
311 
312 #define iscsi_iface_to_shost(_iface) \
313 	dev_to_shost(_iface->dev.parent)
314 
315 
316 struct iscsi_bus_flash_conn {
317 	struct list_head conn_list;	/* item in connlist */
318 	void *dd_data;			/* LLD private data */
319 	struct iscsi_transport *transport;
320 	struct device dev;		/* sysfs transport/container device */
321 	/* iscsi connection parameters */
322 	uint32_t		exp_statsn;
323 	uint32_t		statsn;
324 	unsigned		max_recv_dlength; /* initiator_max_recv_dsl*/
325 	unsigned		max_xmit_dlength; /* target_max_recv_dsl */
326 	unsigned		max_segment_size;
327 	unsigned		tcp_xmit_wsf;
328 	unsigned		tcp_recv_wsf;
329 	int			hdrdgst_en;
330 	int			datadgst_en;
331 	int			port;
332 	char			*ipaddress;
333 	char			*link_local_ipv6_addr;
334 	char			*redirect_ipaddr;
335 	uint16_t		keepalive_timeout;
336 	uint16_t		local_port;
337 	uint8_t			snack_req_en;
338 	/* tcp timestamp negotiation status */
339 	uint8_t			tcp_timestamp_stat;
340 	uint8_t			tcp_nagle_disable;
341 	/* tcp window scale factor */
342 	uint8_t			tcp_wsf_disable;
343 	uint8_t			tcp_timer_scale;
344 	uint8_t			tcp_timestamp_en;
345 	uint8_t			ipv4_tos;
346 	uint8_t			ipv6_traffic_class;
347 	uint8_t			ipv6_flow_label;
348 	uint8_t			fragment_disable;
349 	/* Link local IPv6 address is assigned by firmware or driver */
350 	uint8_t			is_fw_assigned_ipv6;
351 };
352 
353 #define iscsi_dev_to_flash_conn(_dev) \
354 	container_of(_dev, struct iscsi_bus_flash_conn, dev)
355 
356 #define iscsi_flash_conn_to_flash_session(_conn) \
357 	iscsi_dev_to_flash_session(_conn->dev.parent)
358 
359 #define ISID_SIZE 6
360 
361 struct iscsi_bus_flash_session {
362 	struct list_head sess_list;		/* item in session_list */
363 	struct iscsi_transport *transport;
364 	unsigned int target_id;
365 	int flash_state;	/* persistent or non-persistent */
366 	void *dd_data;				/* LLD private data */
367 	struct device dev;	/* sysfs transport/container device */
368 	/* iscsi session parameters */
369 	unsigned		first_burst;
370 	unsigned		max_burst;
371 	unsigned short		max_r2t;
372 	int			default_taskmgmt_timeout;
373 	int			initial_r2t_en;
374 	int			imm_data_en;
375 	int			time2wait;
376 	int			time2retain;
377 	int			pdu_inorder_en;
378 	int			dataseq_inorder_en;
379 	int			erl;
380 	int			tpgt;
381 	char			*username;
382 	char			*username_in;
383 	char			*password;
384 	char			*password_in;
385 	char			*targetname;
386 	char			*targetalias;
387 	char			*portal_type;
388 	uint16_t		tsid;
389 	uint16_t		chap_in_idx;
390 	uint16_t		chap_out_idx;
391 	/* index of iSCSI discovery session if the entry is
392 	 * discovered by iSCSI discovery session
393 	 */
394 	uint16_t		discovery_parent_idx;
395 	/* indicates if discovery was done through iSNS discovery service
396 	 * or through sendTarget */
397 	uint16_t		discovery_parent_type;
398 	/* Firmware auto sendtarget discovery disable */
399 	uint8_t			auto_snd_tgt_disable;
400 	uint8_t			discovery_sess;
401 	/* indicates if this flashnode entry is enabled or disabled */
402 	uint8_t			entry_state;
403 	uint8_t			chap_auth_en;
404 	/* enables firmware to auto logout the discovery session on discovery
405 	 * completion
406 	 */
407 	uint8_t			discovery_logout_en;
408 	uint8_t			bidi_chap_en;
409 	/* makes authentication for discovery session optional */
410 	uint8_t			discovery_auth_optional;
411 	uint8_t			isid[ISID_SIZE];
412 	uint8_t			is_boot_target;
413 };
414 
415 #define iscsi_dev_to_flash_session(_dev) \
416 	container_of(_dev, struct iscsi_bus_flash_session, dev)
417 
418 #define iscsi_flash_session_to_shost(_session) \
419 	dev_to_shost(_session->dev.parent)
420 
421 /*
422  * session and connection functions that can be used by HW iSCSI LLDs
423  */
424 #define iscsi_cls_session_printk(prefix, _cls_session, fmt, a...) \
425 	dev_printk(prefix, &(_cls_session)->dev, fmt, ##a)
426 
427 #define iscsi_cls_conn_printk(prefix, _cls_conn, fmt, a...) \
428 	dev_printk(prefix, &(_cls_conn)->dev, fmt, ##a)
429 
430 extern int iscsi_session_chkready(struct iscsi_cls_session *session);
431 extern int iscsi_is_session_online(struct iscsi_cls_session *session);
432 extern struct iscsi_cls_session *iscsi_alloc_session(struct Scsi_Host *shost,
433 				struct iscsi_transport *transport, int dd_size);
434 extern int iscsi_add_session(struct iscsi_cls_session *session,
435 			     unsigned int target_id);
436 extern int iscsi_session_event(struct iscsi_cls_session *session,
437 			       enum iscsi_uevent_e event);
438 extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
439 						struct iscsi_transport *t,
440 						int dd_size,
441 						unsigned int target_id);
442 extern void iscsi_remove_session(struct iscsi_cls_session *session);
443 extern void iscsi_free_session(struct iscsi_cls_session *session);
444 extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
445 						int dd_size, uint32_t cid);
446 extern void iscsi_put_conn(struct iscsi_cls_conn *conn);
447 extern void iscsi_get_conn(struct iscsi_cls_conn *conn);
448 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
449 extern void iscsi_unblock_session(struct iscsi_cls_session *session);
450 extern void iscsi_block_session(struct iscsi_cls_session *session);
451 extern int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time);
452 extern struct iscsi_endpoint *iscsi_create_endpoint(int dd_size);
453 extern void iscsi_destroy_endpoint(struct iscsi_endpoint *ep);
454 extern struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle);
455 extern void iscsi_put_endpoint(struct iscsi_endpoint *ep);
456 extern int iscsi_block_scsi_eh(struct scsi_cmnd *cmd);
457 extern struct iscsi_iface *iscsi_create_iface(struct Scsi_Host *shost,
458 					      struct iscsi_transport *t,
459 					      uint32_t iface_type,
460 					      uint32_t iface_num, int dd_size);
461 extern void iscsi_destroy_iface(struct iscsi_iface *iface);
462 extern struct iscsi_iface *iscsi_lookup_iface(int handle);
463 extern char *iscsi_get_port_speed_name(struct Scsi_Host *shost);
464 extern char *iscsi_get_port_state_name(struct Scsi_Host *shost);
465 extern int iscsi_is_session_dev(const struct device *dev);
466 
467 extern char *iscsi_get_discovery_parent_name(int parent_type);
468 extern struct device *
469 iscsi_find_flashnode(struct Scsi_Host *shost, void *data,
470 		     int (*fn)(struct device *dev, void *data));
471 
472 extern struct iscsi_bus_flash_session *
473 iscsi_create_flashnode_sess(struct Scsi_Host *shost, int index,
474 			    struct iscsi_transport *transport, int dd_size);
475 
476 extern struct iscsi_bus_flash_conn *
477 iscsi_create_flashnode_conn(struct Scsi_Host *shost,
478 			    struct iscsi_bus_flash_session *fnode_sess,
479 			    struct iscsi_transport *transport, int dd_size);
480 
481 extern void
482 iscsi_destroy_flashnode_sess(struct iscsi_bus_flash_session *fnode_sess);
483 
484 extern void iscsi_destroy_all_flashnode(struct Scsi_Host *shost);
485 extern int iscsi_flashnode_bus_match(struct device *dev,
486 				     struct device_driver *drv);
487 extern struct device *
488 iscsi_find_flashnode_sess(struct Scsi_Host *shost, void *data,
489 			  int (*fn)(struct device *dev, void *data));
490 extern struct device *
491 iscsi_find_flashnode_conn(struct iscsi_bus_flash_session *fnode_sess);
492 
493 extern char *
494 iscsi_get_ipaddress_state_name(enum iscsi_ipaddress_state port_state);
495 extern char *iscsi_get_router_state_name(enum iscsi_router_state router_state);
496 #endif
497