xref: /linux/include/scsi/scsi_transport_iscsi.h (revision de2fe5e07d58424bc286fff3fd3c1b0bf933cd58)
1 /*
2  * iSCSI transport class definitions
3  *
4  * Copyright (C) IBM Corporation, 2004
5  * Copyright (C) Mike Christie, 2004 - 2005
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 <scsi/iscsi_if.h>
28 
29 struct scsi_transport_template;
30 struct Scsi_Host;
31 struct mempool_zone;
32 struct iscsi_cls_conn;
33 
34 /**
35  * struct iscsi_transport - iSCSI Transport template
36  *
37  * @name:		transport name
38  * @caps:		iSCSI Data-Path capabilities
39  * @create_session:	create new iSCSI session object
40  * @destroy_session:	destroy existing iSCSI session object
41  * @create_conn:	create new iSCSI connection
42  * @bind_conn:		associate this connection with existing iSCSI session
43  *			and specified transport descriptor
44  * @destroy_conn:	destroy inactive iSCSI connection
45  * @set_param:		set iSCSI Data-Path operational parameter
46  * @start_conn:		set connection to be operational
47  * @stop_conn:		suspend/recover/terminate connection
48  * @send_pdu:		send iSCSI PDU, Login, Logout, NOP-Out, Reject, Text.
49  *
50  * Template API provided by iSCSI Transport
51  */
52 struct iscsi_transport {
53 	struct module *owner;
54 	char *name;
55 	unsigned int caps;
56 	struct scsi_host_template *host_template;
57 	/* LLD session/scsi_host data size */
58 	int hostdata_size;
59 	/* LLD iscsi_host data size */
60 	int ihostdata_size;
61 	/* LLD connection data size */
62 	int conndata_size;
63 	int max_lun;
64 	unsigned int max_conn;
65 	unsigned int max_cmd_len;
66 	struct iscsi_cls_session *(*create_session)
67 		(struct scsi_transport_template *t, uint32_t sn, uint32_t *sid);
68 	void (*destroy_session) (struct iscsi_cls_session *session);
69 	struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess,
70 				uint32_t cid);
71 	int (*bind_conn) (struct iscsi_cls_session *session,
72 			  struct iscsi_cls_conn *cls_conn,
73 			  uint32_t transport_fd, int is_leading);
74 	int (*start_conn) (struct iscsi_cls_conn *conn);
75 	void (*stop_conn) (struct iscsi_cls_conn *conn, int flag);
76 	void (*destroy_conn) (struct iscsi_cls_conn *conn);
77 	int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param,
78 			  uint32_t value);
79 	int (*get_conn_param) (struct iscsi_cls_conn *conn,
80 			       enum iscsi_param param,
81 			       uint32_t *value);
82 	int (*get_session_param) (struct iscsi_cls_session *session,
83 				  enum iscsi_param param, uint32_t *value);
84 	int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
85 			 char *data, uint32_t data_size);
86 	void (*get_stats) (struct iscsi_cls_conn *conn,
87 			   struct iscsi_stats *stats);
88 };
89 
90 /*
91  * transport registration upcalls
92  */
93 extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt);
94 extern int iscsi_unregister_transport(struct iscsi_transport *tt);
95 
96 /*
97  * control plane upcalls
98  */
99 extern void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error);
100 extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
101 			  char *data, uint32_t data_size);
102 
103 struct iscsi_cls_conn {
104 	struct list_head conn_list;	/* item in connlist */
105 	void *dd_data;			/* LLD private data */
106 	struct iscsi_transport *transport;
107 	int active;			/* must be accessed with the connlock */
108 	struct device dev;		/* sysfs transport/container device */
109 	struct mempool_zone *z_error;
110 	struct mempool_zone *z_pdu;
111 	struct list_head freequeue;
112 };
113 
114 #define iscsi_dev_to_conn(_dev) \
115 	container_of(_dev, struct iscsi_cls_conn, dev)
116 
117 struct iscsi_cls_session {
118 	struct list_head sess_list;		/* item in session_list */
119 	struct iscsi_transport *transport;
120 	struct device dev;	/* sysfs transport/container device */
121 };
122 
123 #define iscsi_dev_to_session(_dev) \
124 	container_of(_dev, struct iscsi_cls_session, dev)
125 
126 #define iscsi_session_to_shost(_session) \
127 	dev_to_shost(_session->dev.parent)
128 
129 /*
130  * session and connection functions that can be used by HW iSCSI LLDs
131  */
132 extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
133 				struct iscsi_transport *t);
134 extern int iscsi_destroy_session(struct iscsi_cls_session *session);
135 extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
136 					    uint32_t cid);
137 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
138 
139 /*
140  * session functions used by software iscsi
141  */
142 extern struct Scsi_Host *
143 iscsi_transport_create_session(struct scsi_transport_template *scsit,
144                                struct iscsi_transport *transport);
145 extern int iscsi_transport_destroy_session(struct Scsi_Host *shost);
146 
147 #endif
148