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 29 struct scsi_transport_template; 30 struct iscsi_transport; 31 struct Scsi_Host; 32 struct mempool_zone; 33 struct iscsi_cls_conn; 34 struct iscsi_conn; 35 struct iscsi_cmd_task; 36 struct iscsi_mgmt_task; 37 struct 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 * @suspend_conn_recv: susepend the recv side of the connection 61 * @termincate_conn: destroy socket connection. Called with mutex lock. 62 * @init_cmd_task: Initialize a iscsi_cmd_task and any internal structs. 63 * Called from queuecommand with session lock held. 64 * @init_mgmt_task: Initialize a iscsi_mgmt_task and any internal structs. 65 * Called from iscsi_conn_send_generic with xmitmutex. 66 * @xmit_cmd_task: Requests LLD to transfer cmd task. Returns 0 or the 67 * the number of bytes transferred on success, and -Exyz 68 * value on error. 69 * @xmit_mgmt_task: Requests LLD to transfer mgmt task. Returns 0 or the 70 * the number of bytes transferred on success, and -Exyz 71 * value on error. 72 * @cleanup_cmd_task: requests LLD to fail cmd task. Called with xmitmutex 73 * and session->lock after the connection has been 74 * suspended and terminated during recovery. If called 75 * from abort task then connection is not suspended 76 * or terminated but sk_callback_lock is held 77 * 78 * Template API provided by iSCSI Transport 79 */ 80 struct iscsi_transport { 81 struct module *owner; 82 char *name; 83 unsigned int caps; 84 /* LLD sets this to indicate what values it can export to sysfs */ 85 unsigned int param_mask; 86 struct scsi_host_template *host_template; 87 /* LLD connection data size */ 88 int conndata_size; 89 /* LLD session data size */ 90 int sessiondata_size; 91 int max_lun; 92 unsigned int max_conn; 93 unsigned int max_cmd_len; 94 struct iscsi_cls_session *(*create_session) (struct iscsi_transport *it, 95 struct scsi_transport_template *t, uint32_t sn, uint32_t *hn); 96 void (*destroy_session) (struct iscsi_cls_session *session); 97 struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess, 98 uint32_t cid); 99 int (*bind_conn) (struct iscsi_cls_session *session, 100 struct iscsi_cls_conn *cls_conn, 101 uint64_t transport_eph, int is_leading); 102 int (*start_conn) (struct iscsi_cls_conn *conn); 103 void (*stop_conn) (struct iscsi_cls_conn *conn, int flag); 104 void (*destroy_conn) (struct iscsi_cls_conn *conn); 105 int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param, 106 char *buf, int buflen); 107 int (*get_conn_param) (struct iscsi_cls_conn *conn, 108 enum iscsi_param param, char *buf); 109 int (*get_session_param) (struct iscsi_cls_session *session, 110 enum iscsi_param param, char *buf); 111 int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr, 112 char *data, uint32_t data_size); 113 void (*get_stats) (struct iscsi_cls_conn *conn, 114 struct iscsi_stats *stats); 115 void (*suspend_conn_recv) (struct iscsi_conn *conn); 116 void (*terminate_conn) (struct iscsi_conn *conn); 117 void (*init_cmd_task) (struct iscsi_cmd_task *ctask); 118 void (*init_mgmt_task) (struct iscsi_conn *conn, 119 struct iscsi_mgmt_task *mtask, 120 char *data, uint32_t data_size); 121 int (*xmit_cmd_task) (struct iscsi_conn *conn, 122 struct iscsi_cmd_task *ctask); 123 void (*cleanup_cmd_task) (struct iscsi_conn *conn, 124 struct iscsi_cmd_task *ctask); 125 int (*xmit_mgmt_task) (struct iscsi_conn *conn, 126 struct iscsi_mgmt_task *mtask); 127 void (*session_recovery_timedout) (struct iscsi_cls_session *session); 128 int (*ep_connect) (struct sockaddr *dst_addr, int non_blocking, 129 uint64_t *ep_handle); 130 int (*ep_poll) (uint64_t ep_handle, int timeout_ms); 131 void (*ep_disconnect) (uint64_t ep_handle); 132 int (*tgt_dscvr) (enum iscsi_tgt_dscvr type, uint32_t host_no, 133 uint32_t enable, struct sockaddr *dst_addr); 134 }; 135 136 /* 137 * transport registration upcalls 138 */ 139 extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt); 140 extern int iscsi_unregister_transport(struct iscsi_transport *tt); 141 142 /* 143 * control plane upcalls 144 */ 145 extern void iscsi_conn_error(struct iscsi_cls_conn *conn, enum iscsi_err error); 146 extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr, 147 char *data, uint32_t data_size); 148 149 150 /* Connection's states */ 151 #define ISCSI_CONN_INITIAL_STAGE 0 152 #define ISCSI_CONN_STARTED 1 153 #define ISCSI_CONN_STOPPED 2 154 #define ISCSI_CONN_CLEANUP_WAIT 3 155 156 struct iscsi_cls_conn { 157 struct list_head conn_list; /* item in connlist */ 158 void *dd_data; /* LLD private data */ 159 struct iscsi_transport *transport; 160 uint32_t cid; /* connection id */ 161 162 int active; /* must be accessed with the connlock */ 163 struct device dev; /* sysfs transport/container device */ 164 struct mempool_zone *z_error; 165 struct mempool_zone *z_pdu; 166 struct list_head freequeue; 167 }; 168 169 #define iscsi_dev_to_conn(_dev) \ 170 container_of(_dev, struct iscsi_cls_conn, dev) 171 172 /* Session's states */ 173 #define ISCSI_STATE_FREE 1 174 #define ISCSI_STATE_LOGGED_IN 2 175 #define ISCSI_STATE_FAILED 3 176 #define ISCSI_STATE_TERMINATE 4 177 #define ISCSI_STATE_IN_RECOVERY 5 178 #define ISCSI_STATE_RECOVERY_FAILED 6 179 180 struct iscsi_cls_session { 181 struct list_head sess_list; /* item in session_list */ 182 struct list_head host_list; 183 struct iscsi_transport *transport; 184 185 /* recovery fields */ 186 int recovery_tmo; 187 struct work_struct recovery_work; 188 189 int target_id; 190 int channel; 191 192 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 struct iscsi_host { 204 int next_target_id; 205 struct list_head sessions; 206 struct mutex mutex; 207 }; 208 209 /* 210 * session and connection functions that can be used by HW iSCSI LLDs 211 */ 212 extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost, 213 struct iscsi_transport *t, int channel); 214 extern int iscsi_destroy_session(struct iscsi_cls_session *session); 215 extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess, 216 uint32_t cid); 217 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn); 218 extern void iscsi_unblock_session(struct iscsi_cls_session *session); 219 extern void iscsi_block_session(struct iscsi_cls_session *session); 220 221 #endif 222