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Linux kernel mirror (for testing)
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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 <scsi/iscsi_if.h>
28
29struct scsi_transport_template;
30struct iscsi_transport;
31struct Scsi_Host;
32struct mempool_zone;
33struct iscsi_cls_conn;
34struct iscsi_conn;
35struct iscsi_cmd_task;
36struct iscsi_mgmt_task;
37struct sockaddr;
38
39/**
40 * struct iscsi_transport - iSCSI Transport template
41 *
42 * @name: transport name
43 * @caps: iSCSI Data-Path capabilities
44 * @create_session: create new iSCSI session object
45 * @destroy_session: destroy existing iSCSI session object
46 * @create_conn: create new iSCSI connection
47 * @bind_conn: associate this connection with existing iSCSI session
48 * and specified transport descriptor
49 * @destroy_conn: destroy inactive iSCSI connection
50 * @set_param: set iSCSI parameter. Return 0 on success, -ENODATA
51 * when param is not supported, and a -Exx value on other
52 * error.
53 * @get_param get iSCSI parameter. Must return number of bytes
54 * copied to buffer on success, -ENODATA when param
55 * is not supported, and a -Exx value on other error
56 * @start_conn: set connection to be operational
57 * @stop_conn: suspend/recover/terminate connection
58 * @send_pdu: send iSCSI PDU, Login, Logout, NOP-Out, Reject, Text.
59 * @session_recovery_timedout: notify LLD a block during recovery timed out
60 * @init_cmd_task: Initialize a iscsi_cmd_task and any internal structs.
61 * Called from queuecommand with session lock held.
62 * @init_mgmt_task: Initialize a iscsi_mgmt_task and any internal structs.
63 * Called from iscsi_conn_send_generic with xmitmutex.
64 * @xmit_cmd_task: Requests LLD to transfer cmd task. Returns 0 or the
65 * the number of bytes transferred on success, and -Exyz
66 * value on error.
67 * @xmit_mgmt_task: Requests LLD to transfer mgmt task. Returns 0 or the
68 * the number of bytes transferred on success, and -Exyz
69 * value on error.
70 * @cleanup_cmd_task: requests LLD to fail cmd task. Called with xmitmutex
71 * and session->lock after the connection has been
72 * suspended and terminated during recovery. If called
73 * from abort task then connection is not suspended
74 * or terminated but sk_callback_lock is held
75 *
76 * Template API provided by iSCSI Transport
77 */
78struct iscsi_transport {
79 struct module *owner;
80 char *name;
81 unsigned int caps;
82 /* LLD sets this to indicate what values it can export to sysfs */
83 unsigned int param_mask;
84 struct scsi_host_template *host_template;
85 /* LLD connection data size */
86 int conndata_size;
87 /* LLD session data size */
88 int sessiondata_size;
89 int max_lun;
90 unsigned int max_conn;
91 unsigned int max_cmd_len;
92 struct iscsi_cls_session *(*create_session) (struct iscsi_transport *it,
93 struct scsi_transport_template *t, uint32_t sn, uint32_t *hn);
94 void (*destroy_session) (struct iscsi_cls_session *session);
95 struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess,
96 uint32_t cid);
97 int (*bind_conn) (struct iscsi_cls_session *session,
98 struct iscsi_cls_conn *cls_conn,
99 uint64_t transport_eph, int is_leading);
100 int (*start_conn) (struct iscsi_cls_conn *conn);
101 void (*stop_conn) (struct iscsi_cls_conn *conn, int flag);
102 void (*destroy_conn) (struct iscsi_cls_conn *conn);
103 int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param,
104 char *buf, int buflen);
105 int (*get_conn_param) (struct iscsi_cls_conn *conn,
106 enum iscsi_param param, char *buf);
107 int (*get_session_param) (struct iscsi_cls_session *session,
108 enum iscsi_param param, char *buf);
109 int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
110 char *data, uint32_t data_size);
111 void (*get_stats) (struct iscsi_cls_conn *conn,
112 struct iscsi_stats *stats);
113 void (*init_cmd_task) (struct iscsi_cmd_task *ctask);
114 void (*init_mgmt_task) (struct iscsi_conn *conn,
115 struct iscsi_mgmt_task *mtask,
116 char *data, uint32_t data_size);
117 int (*xmit_cmd_task) (struct iscsi_conn *conn,
118 struct iscsi_cmd_task *ctask);
119 void (*cleanup_cmd_task) (struct iscsi_conn *conn,
120 struct iscsi_cmd_task *ctask);
121 int (*xmit_mgmt_task) (struct iscsi_conn *conn,
122 struct iscsi_mgmt_task *mtask);
123 void (*session_recovery_timedout) (struct iscsi_cls_session *session);
124 int (*ep_connect) (struct sockaddr *dst_addr, int non_blocking,
125 uint64_t *ep_handle);
126 int (*ep_poll) (uint64_t ep_handle, int timeout_ms);
127 void (*ep_disconnect) (uint64_t ep_handle);
128 int (*tgt_dscvr) (enum iscsi_tgt_dscvr type, uint32_t host_no,
129 uint32_t enable, struct sockaddr *dst_addr);
130};
131
132/*
133 * transport registration upcalls
134 */
135extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt);
136extern int iscsi_unregister_transport(struct iscsi_transport *tt);
137
138/*
139 * control plane upcalls
140 */
141extern void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error);
142extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr,
143 char *data, uint32_t data_size);
144
145
146/* Connection's states */
147#define ISCSI_CONN_INITIAL_STAGE 0
148#define ISCSI_CONN_STARTED 1
149#define ISCSI_CONN_STOPPED 2
150#define ISCSI_CONN_CLEANUP_WAIT 3
151
152struct iscsi_cls_conn {
153 struct list_head conn_list; /* item in connlist */
154 void *dd_data; /* LLD private data */
155 struct iscsi_transport *transport;
156 uint32_t cid; /* connection id */
157
158 int active; /* must be accessed with the connlock */
159 struct device dev; /* sysfs transport/container device */
160 struct mempool_zone *z_error;
161 struct mempool_zone *z_pdu;
162 struct list_head freequeue;
163};
164
165#define iscsi_dev_to_conn(_dev) \
166 container_of(_dev, struct iscsi_cls_conn, dev)
167
168/* Session's states */
169#define ISCSI_STATE_FREE 1
170#define ISCSI_STATE_LOGGED_IN 2
171#define ISCSI_STATE_FAILED 3
172#define ISCSI_STATE_TERMINATE 4
173#define ISCSI_STATE_IN_RECOVERY 5
174#define ISCSI_STATE_RECOVERY_FAILED 6
175
176struct iscsi_cls_session {
177 struct list_head sess_list; /* item in session_list */
178 struct list_head host_list;
179 struct iscsi_transport *transport;
180
181 /* recovery fields */
182 int recovery_tmo;
183 struct work_struct recovery_work;
184
185 int target_id;
186
187 int sid; /* session id */
188 void *dd_data; /* LLD private data */
189 struct device dev; /* sysfs transport/container device */
190};
191
192#define iscsi_dev_to_session(_dev) \
193 container_of(_dev, struct iscsi_cls_session, dev)
194
195#define iscsi_session_to_shost(_session) \
196 dev_to_shost(_session->dev.parent)
197
198#define starget_to_session(_stgt) \
199 iscsi_dev_to_session(_stgt->dev.parent)
200
201struct iscsi_host {
202 struct list_head sessions;
203 struct mutex mutex;
204};
205
206/*
207 * session and connection functions that can be used by HW iSCSI LLDs
208 */
209extern struct iscsi_cls_session *iscsi_alloc_session(struct Scsi_Host *shost,
210 struct iscsi_transport *transport);
211extern int iscsi_add_session(struct iscsi_cls_session *session,
212 unsigned int target_id);
213extern int iscsi_if_create_session_done(struct iscsi_cls_conn *conn);
214extern int iscsi_if_destroy_session_done(struct iscsi_cls_conn *conn);
215extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
216 struct iscsi_transport *t,
217 unsigned int target_id);
218extern void iscsi_remove_session(struct iscsi_cls_session *session);
219extern void iscsi_free_session(struct iscsi_cls_session *session);
220extern int iscsi_destroy_session(struct iscsi_cls_session *session);
221extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
222 uint32_t cid);
223extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);
224extern void iscsi_unblock_session(struct iscsi_cls_session *session);
225extern void iscsi_block_session(struct iscsi_cls_session *session);
226
227
228#endif