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 iscsi_cls_conn; 36 struct iscsi_conn; 37 struct iscsi_task; 38 struct sockaddr; 39 40 /** 41 * struct iscsi_transport - iSCSI Transport template 42 * 43 * @name: transport name 44 * @caps: iSCSI Data-Path capabilities 45 * @create_session: create new iSCSI session object 46 * @destroy_session: destroy existing iSCSI session object 47 * @create_conn: create new iSCSI connection 48 * @bind_conn: associate this connection with existing iSCSI session 49 * and specified transport descriptor 50 * @destroy_conn: destroy inactive iSCSI connection 51 * @set_param: set iSCSI parameter. Return 0 on success, -ENODATA 52 * when param is not supported, and a -Exx value on other 53 * error. 54 * @get_param get iSCSI parameter. Must return number of bytes 55 * copied to buffer on success, -ENODATA when param 56 * is not supported, and a -Exx value on other error 57 * @start_conn: set connection to be operational 58 * @stop_conn: suspend/recover/terminate connection 59 * @send_pdu: send iSCSI PDU, Login, Logout, NOP-Out, Reject, Text. 60 * @session_recovery_timedout: notify LLD a block during recovery timed out 61 * @init_task: Initialize a iscsi_task and any internal structs. 62 * When offloading the data path, this is called from 63 * queuecommand with the session lock, or from the 64 * iscsi_conn_send_pdu context with the session lock. 65 * When not offloading the data path, this is called 66 * from the scsi work queue without the session lock. 67 * @xmit_task Requests LLD to transfer cmd task. Returns 0 or the 68 * the number of bytes transferred on success, and -Exyz 69 * value on error. When offloading the data path, this 70 * is called from queuecommand with the session lock, or 71 * from the iscsi_conn_send_pdu context with the session 72 * lock. When not offloading the data path, this is called 73 * from the scsi work queue without the session lock. 74 * @cleanup_task: requests LLD to fail task. Called with session lock 75 * and after the connection has been suspended and 76 * terminated during recovery. If called 77 * from abort task then connection is not suspended 78 * or terminated but sk_callback_lock is held 79 * 80 * Template API provided by iSCSI Transport 81 */ 82 struct iscsi_transport { 83 struct module *owner; 84 char *name; 85 unsigned int caps; 86 /* LLD sets this to indicate what values it can export to sysfs */ 87 uint64_t param_mask; 88 uint64_t host_param_mask; 89 struct iscsi_cls_session *(*create_session) (struct iscsi_endpoint *ep, 90 uint16_t cmds_max, uint16_t qdepth, 91 uint32_t sn, uint32_t *hn); 92 void (*destroy_session) (struct iscsi_cls_session *session); 93 struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess, 94 uint32_t cid); 95 int (*bind_conn) (struct iscsi_cls_session *session, 96 struct iscsi_cls_conn *cls_conn, 97 uint64_t transport_eph, int is_leading); 98 int (*start_conn) (struct iscsi_cls_conn *conn); 99 void (*stop_conn) (struct iscsi_cls_conn *conn, int flag); 100 void (*destroy_conn) (struct iscsi_cls_conn *conn); 101 int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param, 102 char *buf, int buflen); 103 int (*get_conn_param) (struct iscsi_cls_conn *conn, 104 enum iscsi_param param, char *buf); 105 int (*get_session_param) (struct iscsi_cls_session *session, 106 enum iscsi_param param, char *buf); 107 int (*get_host_param) (struct Scsi_Host *shost, 108 enum iscsi_host_param param, char *buf); 109 int (*set_host_param) (struct Scsi_Host *shost, 110 enum iscsi_host_param param, char *buf, 111 int buflen); 112 int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr, 113 char *data, uint32_t data_size); 114 void (*get_stats) (struct iscsi_cls_conn *conn, 115 struct iscsi_stats *stats); 116 int (*init_task) (struct iscsi_task *task); 117 int (*xmit_task) (struct iscsi_task *task); 118 void (*cleanup_task) (struct iscsi_conn *conn, 119 struct iscsi_task *task); 120 void (*session_recovery_timedout) (struct iscsi_cls_session *session); 121 struct iscsi_endpoint *(*ep_connect) (struct sockaddr *dst_addr, 122 int non_blocking); 123 int (*ep_poll) (struct iscsi_endpoint *ep, int timeout_ms); 124 void (*ep_disconnect) (struct iscsi_endpoint *ep); 125 int (*tgt_dscvr) (struct Scsi_Host *shost, enum iscsi_tgt_dscvr type, 126 uint32_t enable, struct sockaddr *dst_addr); 127 }; 128 129 /* 130 * transport registration upcalls 131 */ 132 extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt); 133 extern int iscsi_unregister_transport(struct iscsi_transport *tt); 134 135 /* 136 * control plane upcalls 137 */ 138 extern void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error); 139 extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr, 140 char *data, uint32_t data_size); 141 142 struct iscsi_cls_conn { 143 struct list_head conn_list; /* item in connlist */ 144 void *dd_data; /* LLD private data */ 145 struct iscsi_transport *transport; 146 uint32_t cid; /* connection id */ 147 148 int active; /* must be accessed with the connlock */ 149 struct device dev; /* sysfs transport/container device */ 150 }; 151 152 #define iscsi_dev_to_conn(_dev) \ 153 container_of(_dev, struct iscsi_cls_conn, dev) 154 155 #define iscsi_conn_to_session(_conn) \ 156 iscsi_dev_to_session(_conn->dev.parent) 157 158 /* iscsi class session state */ 159 enum { 160 ISCSI_SESSION_LOGGED_IN, 161 ISCSI_SESSION_FAILED, 162 ISCSI_SESSION_FREE, 163 }; 164 165 #define ISCSI_MAX_TARGET -1 166 167 struct iscsi_cls_session { 168 struct list_head sess_list; /* item in session_list */ 169 struct iscsi_transport *transport; 170 spinlock_t lock; 171 struct work_struct block_work; 172 struct work_struct unblock_work; 173 struct work_struct scan_work; 174 struct work_struct unbind_work; 175 176 /* recovery fields */ 177 int recovery_tmo; 178 struct delayed_work recovery_work; 179 180 unsigned int target_id; 181 182 int state; 183 int sid; /* session id */ 184 void *dd_data; /* LLD private data */ 185 struct device dev; /* sysfs transport/container device */ 186 }; 187 188 #define iscsi_dev_to_session(_dev) \ 189 container_of(_dev, struct iscsi_cls_session, dev) 190 191 #define iscsi_session_to_shost(_session) \ 192 dev_to_shost(_session->dev.parent) 193 194 #define starget_to_session(_stgt) \ 195 iscsi_dev_to_session(_stgt->dev.parent) 196 197 struct iscsi_cls_host { 198 atomic_t nr_scans; 199 struct mutex mutex; 200 struct workqueue_struct *scan_workq; 201 char scan_workq_name[20]; 202 }; 203 204 extern void iscsi_host_for_each_session(struct Scsi_Host *shost, 205 void (*fn)(struct iscsi_cls_session *)); 206 207 struct iscsi_endpoint { 208 void *dd_data; /* LLD private data */ 209 struct device dev; 210 unsigned int id; 211 }; 212 213 /* 214 * session and connection functions that can be used by HW iSCSI LLDs 215 */ 216 #define iscsi_cls_session_printk(prefix, _cls_session, fmt, a...) \ 217 dev_printk(prefix, &(_cls_session)->dev, fmt, ##a) 218 219 #define iscsi_cls_conn_printk(prefix, _cls_conn, fmt, a...) \ 220 dev_printk(prefix, &(_cls_conn)->dev, fmt, ##a) 221 222 extern int iscsi_session_chkready(struct iscsi_cls_session *session); 223 extern struct iscsi_cls_session *iscsi_alloc_session(struct Scsi_Host *shost, 224 struct iscsi_transport *transport, int dd_size); 225 extern int iscsi_add_session(struct iscsi_cls_session *session, 226 unsigned int target_id); 227 extern int iscsi_session_event(struct iscsi_cls_session *session, 228 enum iscsi_uevent_e event); 229 extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost, 230 struct iscsi_transport *t, 231 int dd_size, 232 unsigned int target_id); 233 extern void iscsi_remove_session(struct iscsi_cls_session *session); 234 extern void iscsi_free_session(struct iscsi_cls_session *session); 235 extern int iscsi_destroy_session(struct iscsi_cls_session *session); 236 extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess, 237 int dd_size, uint32_t cid); 238 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn); 239 extern void iscsi_unblock_session(struct iscsi_cls_session *session); 240 extern void iscsi_block_session(struct iscsi_cls_session *session); 241 extern int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time); 242 extern struct iscsi_endpoint *iscsi_create_endpoint(int dd_size); 243 extern void iscsi_destroy_endpoint(struct iscsi_endpoint *ep); 244 extern struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle); 245 246 #endif 247