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); 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); 116 117 int (*init_task) (struct iscsi_task *task); 118 int (*xmit_task) (struct iscsi_task *task); 119 void (*cleanup_task) (struct iscsi_task *task); 120 121 int (*alloc_pdu) (struct iscsi_task *task, uint8_t opcode); 122 int (*xmit_pdu) (struct iscsi_task *task); 123 int (*init_pdu) (struct iscsi_task *task, unsigned int offset, 124 unsigned int count); 125 void (*parse_pdu_itt) (struct iscsi_conn *conn, itt_t itt, 126 int *index, int *age); 127 128 void (*session_recovery_timedout) (struct iscsi_cls_session *session); 129 struct iscsi_endpoint *(*ep_connect) (struct sockaddr *dst_addr, 130 int non_blocking); 131 int (*ep_poll) (struct iscsi_endpoint *ep, int timeout_ms); 132 void (*ep_disconnect) (struct iscsi_endpoint *ep); 133 int (*tgt_dscvr) (struct Scsi_Host *shost, enum iscsi_tgt_dscvr type, 134 uint32_t enable, struct sockaddr *dst_addr); 135 }; 136 137 /* 138 * transport registration upcalls 139 */ 140 extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt); 141 extern int iscsi_unregister_transport(struct iscsi_transport *tt); 142 143 /* 144 * control plane upcalls 145 */ 146 extern void iscsi_conn_error_event(struct iscsi_cls_conn *conn, 147 enum iscsi_err error); 148 extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr, 149 char *data, uint32_t data_size); 150 151 struct iscsi_cls_conn { 152 struct list_head conn_list; /* item in connlist */ 153 void *dd_data; /* LLD private data */ 154 struct iscsi_transport *transport; 155 uint32_t cid; /* connection id */ 156 157 int active; /* must be accessed with the connlock */ 158 struct device dev; /* sysfs transport/container device */ 159 }; 160 161 #define iscsi_dev_to_conn(_dev) \ 162 container_of(_dev, struct iscsi_cls_conn, dev) 163 164 #define iscsi_conn_to_session(_conn) \ 165 iscsi_dev_to_session(_conn->dev.parent) 166 167 /* iscsi class session state */ 168 enum { 169 ISCSI_SESSION_LOGGED_IN, 170 ISCSI_SESSION_FAILED, 171 ISCSI_SESSION_FREE, 172 }; 173 174 #define ISCSI_MAX_TARGET -1 175 176 struct iscsi_cls_session { 177 struct list_head sess_list; /* item in session_list */ 178 struct iscsi_transport *transport; 179 spinlock_t lock; 180 struct work_struct block_work; 181 struct work_struct unblock_work; 182 struct work_struct scan_work; 183 struct work_struct unbind_work; 184 185 /* recovery fields */ 186 int recovery_tmo; 187 struct delayed_work recovery_work; 188 189 unsigned int target_id; 190 191 int state; 192 int sid; /* session id */ 193 void *dd_data; /* LLD private data */ 194 struct device dev; /* sysfs transport/container device */ 195 }; 196 197 #define iscsi_dev_to_session(_dev) \ 198 container_of(_dev, struct iscsi_cls_session, dev) 199 200 #define iscsi_session_to_shost(_session) \ 201 dev_to_shost(_session->dev.parent) 202 203 #define starget_to_session(_stgt) \ 204 iscsi_dev_to_session(_stgt->dev.parent) 205 206 struct iscsi_cls_host { 207 atomic_t nr_scans; 208 struct mutex mutex; 209 }; 210 211 extern void iscsi_host_for_each_session(struct Scsi_Host *shost, 212 void (*fn)(struct iscsi_cls_session *)); 213 214 struct iscsi_endpoint { 215 void *dd_data; /* LLD private data */ 216 struct device dev; 217 uint64_t id; 218 }; 219 220 /* 221 * session and connection functions that can be used by HW iSCSI LLDs 222 */ 223 #define iscsi_cls_session_printk(prefix, _cls_session, fmt, a...) \ 224 dev_printk(prefix, &(_cls_session)->dev, fmt, ##a) 225 226 #define iscsi_cls_conn_printk(prefix, _cls_conn, fmt, a...) \ 227 dev_printk(prefix, &(_cls_conn)->dev, fmt, ##a) 228 229 extern int iscsi_session_chkready(struct iscsi_cls_session *session); 230 extern struct iscsi_cls_session *iscsi_alloc_session(struct Scsi_Host *shost, 231 struct iscsi_transport *transport, int dd_size); 232 extern int iscsi_add_session(struct iscsi_cls_session *session, 233 unsigned int target_id); 234 extern int iscsi_session_event(struct iscsi_cls_session *session, 235 enum iscsi_uevent_e event); 236 extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost, 237 struct iscsi_transport *t, 238 int dd_size, 239 unsigned int target_id); 240 extern void iscsi_remove_session(struct iscsi_cls_session *session); 241 extern void iscsi_free_session(struct iscsi_cls_session *session); 242 extern int iscsi_destroy_session(struct iscsi_cls_session *session); 243 extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess, 244 int dd_size, uint32_t cid); 245 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn); 246 extern void iscsi_unblock_session(struct iscsi_cls_session *session); 247 extern void iscsi_block_session(struct iscsi_cls_session *session); 248 extern int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time); 249 extern struct iscsi_endpoint *iscsi_create_endpoint(int dd_size); 250 extern void iscsi_destroy_endpoint(struct iscsi_endpoint *ep); 251 extern struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle); 252 253 #endif 254