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 31struct scsi_transport_template; 32struct iscsi_transport; 33struct iscsi_endpoint; 34struct Scsi_Host; 35struct scsi_cmnd; 36struct iscsi_cls_conn; 37struct iscsi_conn; 38struct iscsi_task; 39struct sockaddr; 40 41/** 42 * struct iscsi_transport - iSCSI Transport template 43 * 44 * @name: transport name 45 * @caps: iSCSI Data-Path capabilities 46 * @create_session: create new iSCSI session object 47 * @destroy_session: destroy existing iSCSI session object 48 * @create_conn: create new iSCSI connection 49 * @bind_conn: associate this connection with existing iSCSI session 50 * and specified transport descriptor 51 * @destroy_conn: destroy inactive iSCSI connection 52 * @set_param: set iSCSI parameter. Return 0 on success, -ENODATA 53 * when param is not supported, and a -Exx value on other 54 * error. 55 * @get_param get iSCSI parameter. Must return number of bytes 56 * copied to buffer on success, -ENODATA when param 57 * is not supported, and a -Exx value on other error 58 * @start_conn: set connection to be operational 59 * @stop_conn: suspend/recover/terminate connection 60 * @send_pdu: send iSCSI PDU, Login, Logout, NOP-Out, Reject, Text. 61 * @session_recovery_timedout: notify LLD a block during recovery timed out 62 * @init_task: Initialize a iscsi_task and any internal structs. 63 * When offloading the data path, this is called from 64 * queuecommand with the session lock, or from the 65 * iscsi_conn_send_pdu context with the session lock. 66 * When not offloading the data path, this is called 67 * from the scsi work queue without the session lock. 68 * @xmit_task Requests LLD to transfer cmd task. Returns 0 or the 69 * the number of bytes transferred on success, and -Exyz 70 * value on error. When offloading the data path, this 71 * is called from queuecommand with the session lock, or 72 * from the iscsi_conn_send_pdu context with the session 73 * lock. When not offloading the data path, this is called 74 * from the scsi work queue without the session lock. 75 * @cleanup_task: requests LLD to fail task. Called with session lock 76 * and after the connection has been suspended and 77 * terminated during recovery. If called 78 * from abort task then connection is not suspended 79 * or terminated but sk_callback_lock is held 80 * 81 * Template API provided by iSCSI Transport 82 */ 83struct iscsi_transport { 84 struct module *owner; 85 char *name; 86 unsigned int caps; 87 /* LLD sets this to indicate what values it can export to sysfs */ 88 uint64_t param_mask; 89 uint64_t host_param_mask; 90 struct iscsi_cls_session *(*create_session) (struct iscsi_endpoint *ep, 91 uint16_t cmds_max, uint16_t qdepth, 92 uint32_t sn); 93 void (*destroy_session) (struct iscsi_cls_session *session); 94 struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess, 95 uint32_t cid); 96 int (*bind_conn) (struct iscsi_cls_session *session, 97 struct iscsi_cls_conn *cls_conn, 98 uint64_t transport_eph, int is_leading); 99 int (*start_conn) (struct iscsi_cls_conn *conn); 100 void (*stop_conn) (struct iscsi_cls_conn *conn, int flag); 101 void (*destroy_conn) (struct iscsi_cls_conn *conn); 102 int (*set_param) (struct iscsi_cls_conn *conn, enum iscsi_param param, 103 char *buf, int buflen); 104 int (*get_conn_param) (struct iscsi_cls_conn *conn, 105 enum iscsi_param param, char *buf); 106 int (*get_session_param) (struct iscsi_cls_session *session, 107 enum iscsi_param param, char *buf); 108 int (*get_host_param) (struct Scsi_Host *shost, 109 enum iscsi_host_param param, char *buf); 110 int (*set_host_param) (struct Scsi_Host *shost, 111 enum iscsi_host_param param, char *buf, 112 int buflen); 113 int (*send_pdu) (struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr, 114 char *data, uint32_t data_size); 115 void (*get_stats) (struct iscsi_cls_conn *conn, 116 struct iscsi_stats *stats); 117 118 int (*init_task) (struct iscsi_task *task); 119 int (*xmit_task) (struct iscsi_task *task); 120 void (*cleanup_task) (struct iscsi_task *task); 121 122 int (*alloc_pdu) (struct iscsi_task *task, uint8_t opcode); 123 int (*xmit_pdu) (struct iscsi_task *task); 124 int (*init_pdu) (struct iscsi_task *task, unsigned int offset, 125 unsigned int count); 126 void (*parse_pdu_itt) (struct iscsi_conn *conn, itt_t itt, 127 int *index, int *age); 128 129 void (*session_recovery_timedout) (struct iscsi_cls_session *session); 130 struct iscsi_endpoint *(*ep_connect) (struct Scsi_Host *shost, 131 struct sockaddr *dst_addr, 132 int non_blocking); 133 int (*ep_poll) (struct iscsi_endpoint *ep, int timeout_ms); 134 void (*ep_disconnect) (struct iscsi_endpoint *ep); 135 int (*tgt_dscvr) (struct Scsi_Host *shost, enum iscsi_tgt_dscvr type, 136 uint32_t enable, struct sockaddr *dst_addr); 137 int (*set_path) (struct Scsi_Host *shost, struct iscsi_path *params); 138}; 139 140/* 141 * transport registration upcalls 142 */ 143extern struct scsi_transport_template *iscsi_register_transport(struct iscsi_transport *tt); 144extern int iscsi_unregister_transport(struct iscsi_transport *tt); 145 146/* 147 * control plane upcalls 148 */ 149extern void iscsi_conn_error_event(struct iscsi_cls_conn *conn, 150 enum iscsi_err error); 151extern int iscsi_recv_pdu(struct iscsi_cls_conn *conn, struct iscsi_hdr *hdr, 152 char *data, uint32_t data_size); 153 154extern int iscsi_offload_mesg(struct Scsi_Host *shost, 155 struct iscsi_transport *transport, uint32_t type, 156 char *data, uint16_t data_size); 157 158struct iscsi_cls_conn { 159 struct list_head conn_list; /* item in connlist */ 160 void *dd_data; /* LLD private data */ 161 struct iscsi_transport *transport; 162 uint32_t cid; /* connection id */ 163 164 int active; /* must be accessed with the connlock */ 165 struct device dev; /* sysfs transport/container device */ 166}; 167 168#define iscsi_dev_to_conn(_dev) \ 169 container_of(_dev, struct iscsi_cls_conn, dev) 170 171#define iscsi_conn_to_session(_conn) \ 172 iscsi_dev_to_session(_conn->dev.parent) 173 174/* iscsi class session state */ 175enum { 176 ISCSI_SESSION_LOGGED_IN, 177 ISCSI_SESSION_FAILED, 178 ISCSI_SESSION_FREE, 179}; 180 181#define ISCSI_MAX_TARGET -1 182 183struct iscsi_cls_session { 184 struct list_head sess_list; /* item in session_list */ 185 struct iscsi_transport *transport; 186 spinlock_t lock; 187 struct work_struct block_work; 188 struct work_struct unblock_work; 189 struct work_struct scan_work; 190 struct work_struct unbind_work; 191 192 /* recovery fields */ 193 int recovery_tmo; 194 struct delayed_work recovery_work; 195 196 unsigned int target_id; 197 198 int state; 199 int sid; /* session id */ 200 void *dd_data; /* LLD private data */ 201 struct device dev; /* sysfs transport/container device */ 202}; 203 204#define iscsi_dev_to_session(_dev) \ 205 container_of(_dev, struct iscsi_cls_session, dev) 206 207#define iscsi_session_to_shost(_session) \ 208 dev_to_shost(_session->dev.parent) 209 210#define starget_to_session(_stgt) \ 211 iscsi_dev_to_session(_stgt->dev.parent) 212 213struct iscsi_cls_host { 214 atomic_t nr_scans; 215 struct mutex mutex; 216}; 217 218extern void iscsi_host_for_each_session(struct Scsi_Host *shost, 219 void (*fn)(struct iscsi_cls_session *)); 220 221struct iscsi_endpoint { 222 void *dd_data; /* LLD private data */ 223 struct device dev; 224 uint64_t id; 225}; 226 227/* 228 * session and connection functions that can be used by HW iSCSI LLDs 229 */ 230#define iscsi_cls_session_printk(prefix, _cls_session, fmt, a...) \ 231 dev_printk(prefix, &(_cls_session)->dev, fmt, ##a) 232 233#define iscsi_cls_conn_printk(prefix, _cls_conn, fmt, a...) \ 234 dev_printk(prefix, &(_cls_conn)->dev, fmt, ##a) 235 236extern int iscsi_session_chkready(struct iscsi_cls_session *session); 237extern struct iscsi_cls_session *iscsi_alloc_session(struct Scsi_Host *shost, 238 struct iscsi_transport *transport, int dd_size); 239extern int iscsi_add_session(struct iscsi_cls_session *session, 240 unsigned int target_id); 241extern int iscsi_session_event(struct iscsi_cls_session *session, 242 enum iscsi_uevent_e event); 243extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost, 244 struct iscsi_transport *t, 245 int dd_size, 246 unsigned int target_id); 247extern void iscsi_remove_session(struct iscsi_cls_session *session); 248extern void iscsi_free_session(struct iscsi_cls_session *session); 249extern int iscsi_destroy_session(struct iscsi_cls_session *session); 250extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess, 251 int dd_size, uint32_t cid); 252extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn); 253extern void iscsi_unblock_session(struct iscsi_cls_session *session); 254extern void iscsi_block_session(struct iscsi_cls_session *session); 255extern int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time); 256extern struct iscsi_endpoint *iscsi_create_endpoint(int dd_size); 257extern void iscsi_destroy_endpoint(struct iscsi_endpoint *ep); 258extern struct iscsi_endpoint *iscsi_lookup_endpoint(u64 handle); 259extern int iscsi_block_scsi_eh(struct scsi_cmnd *cmd); 260 261#endif 262