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v5.14.15
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * iSCSI lib functions
   4 *
   5 * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
   6 * Copyright (C) 2004 - 2006 Mike Christie
   7 * Copyright (C) 2004 - 2005 Dmitry Yusupov
   8 * Copyright (C) 2004 - 2005 Alex Aizman
   9 * maintained by open-iscsi@googlegroups.com
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  10 */
  11#include <linux/types.h>
  12#include <linux/kfifo.h>
  13#include <linux/delay.h>
  14#include <linux/log2.h>
  15#include <linux/slab.h>
  16#include <linux/sched/signal.h>
  17#include <linux/module.h>
  18#include <asm/unaligned.h>
  19#include <net/tcp.h>
  20#include <scsi/scsi_cmnd.h>
  21#include <scsi/scsi_device.h>
  22#include <scsi/scsi_eh.h>
  23#include <scsi/scsi_tcq.h>
  24#include <scsi/scsi_host.h>
  25#include <scsi/scsi.h>
  26#include <scsi/iscsi_proto.h>
  27#include <scsi/scsi_transport.h>
  28#include <scsi/scsi_transport_iscsi.h>
  29#include <scsi/libiscsi.h>
  30#include <trace/events/iscsi.h>
  31
  32static int iscsi_dbg_lib_conn;
  33module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
  34		   S_IRUGO | S_IWUSR);
  35MODULE_PARM_DESC(debug_libiscsi_conn,
  36		 "Turn on debugging for connections in libiscsi module. "
  37		 "Set to 1 to turn on, and zero to turn off. Default is off.");
  38
  39static int iscsi_dbg_lib_session;
  40module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int,
  41		   S_IRUGO | S_IWUSR);
  42MODULE_PARM_DESC(debug_libiscsi_session,
  43		 "Turn on debugging for sessions in libiscsi module. "
  44		 "Set to 1 to turn on, and zero to turn off. Default is off.");
  45
  46static int iscsi_dbg_lib_eh;
  47module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int,
  48		   S_IRUGO | S_IWUSR);
  49MODULE_PARM_DESC(debug_libiscsi_eh,
  50		 "Turn on debugging for error handling in libiscsi module. "
  51		 "Set to 1 to turn on, and zero to turn off. Default is off.");
  52
  53#define ISCSI_DBG_CONN(_conn, dbg_fmt, arg...)			\
  54	do {							\
  55		if (iscsi_dbg_lib_conn)				\
  56			iscsi_conn_printk(KERN_INFO, _conn,	\
  57					     "%s " dbg_fmt,	\
  58					     __func__, ##arg);	\
  59		iscsi_dbg_trace(trace_iscsi_dbg_conn,		\
  60				&(_conn)->cls_conn->dev,	\
  61				"%s " dbg_fmt, __func__, ##arg);\
  62	} while (0);
  63
  64#define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...)			\
  65	do {								\
  66		if (iscsi_dbg_lib_session)				\
  67			iscsi_session_printk(KERN_INFO, _session,	\
  68					     "%s " dbg_fmt,		\
  69					     __func__, ##arg);		\
  70		iscsi_dbg_trace(trace_iscsi_dbg_session, 		\
  71				&(_session)->cls_session->dev,		\
  72				"%s " dbg_fmt, __func__, ##arg);	\
  73	} while (0);
  74
  75#define ISCSI_DBG_EH(_session, dbg_fmt, arg...)				\
  76	do {								\
  77		if (iscsi_dbg_lib_eh)					\
  78			iscsi_session_printk(KERN_INFO, _session,	\
  79					     "%s " dbg_fmt,		\
  80					     __func__, ##arg);		\
  81		iscsi_dbg_trace(trace_iscsi_dbg_eh,			\
  82				&(_session)->cls_session->dev,		\
  83				"%s " dbg_fmt, __func__, ##arg);	\
  84	} while (0);
  85
  86inline void iscsi_conn_queue_work(struct iscsi_conn *conn)
  87{
  88	struct Scsi_Host *shost = conn->session->host;
  89	struct iscsi_host *ihost = shost_priv(shost);
  90
  91	if (ihost->workq)
  92		queue_work(ihost->workq, &conn->xmitwork);
  93}
  94EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
  95
  96static void __iscsi_update_cmdsn(struct iscsi_session *session,
  97				 uint32_t exp_cmdsn, uint32_t max_cmdsn)
  98{
  99	/*
 100	 * standard specifies this check for when to update expected and
 101	 * max sequence numbers
 102	 */
 103	if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
 104		return;
 105
 106	if (exp_cmdsn != session->exp_cmdsn &&
 107	    !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
 108		session->exp_cmdsn = exp_cmdsn;
 109
 110	if (max_cmdsn != session->max_cmdsn &&
 111	    !iscsi_sna_lt(max_cmdsn, session->max_cmdsn))
 112		session->max_cmdsn = max_cmdsn;
 
 
 
 
 
 
 
 
 113}
 114
 115void iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
 116{
 117	__iscsi_update_cmdsn(session, be32_to_cpu(hdr->exp_cmdsn),
 118			     be32_to_cpu(hdr->max_cmdsn));
 119}
 120EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
 121
 122/**
 123 * iscsi_prep_data_out_pdu - initialize Data-Out
 124 * @task: scsi command task
 125 * @r2t: R2T info
 126 * @hdr: iscsi data in pdu
 127 *
 128 * Notes:
 129 *	Initialize Data-Out within this R2T sequence and finds
 130 *	proper data_offset within this SCSI command.
 131 *
 132 *	This function is called with connection lock taken.
 133 **/
 134void iscsi_prep_data_out_pdu(struct iscsi_task *task, struct iscsi_r2t_info *r2t,
 135			   struct iscsi_data *hdr)
 136{
 137	struct iscsi_conn *conn = task->conn;
 138	unsigned int left = r2t->data_length - r2t->sent;
 139
 140	task->hdr_len = sizeof(struct iscsi_data);
 141
 142	memset(hdr, 0, sizeof(struct iscsi_data));
 143	hdr->ttt = r2t->ttt;
 144	hdr->datasn = cpu_to_be32(r2t->datasn);
 145	r2t->datasn++;
 146	hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
 147	hdr->lun = task->lun;
 148	hdr->itt = task->hdr_itt;
 149	hdr->exp_statsn = r2t->exp_statsn;
 150	hdr->offset = cpu_to_be32(r2t->data_offset + r2t->sent);
 151	if (left > conn->max_xmit_dlength) {
 152		hton24(hdr->dlength, conn->max_xmit_dlength);
 153		r2t->data_count = conn->max_xmit_dlength;
 154		hdr->flags = 0;
 155	} else {
 156		hton24(hdr->dlength, left);
 157		r2t->data_count = left;
 158		hdr->flags = ISCSI_FLAG_CMD_FINAL;
 159	}
 160	conn->dataout_pdus_cnt++;
 161}
 162EXPORT_SYMBOL_GPL(iscsi_prep_data_out_pdu);
 163
 164static int iscsi_add_hdr(struct iscsi_task *task, unsigned len)
 165{
 166	unsigned exp_len = task->hdr_len + len;
 167
 168	if (exp_len > task->hdr_max) {
 169		WARN_ON(1);
 170		return -EINVAL;
 171	}
 172
 173	WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
 174	task->hdr_len = exp_len;
 175	return 0;
 176}
 177
 178/*
 179 * make an extended cdb AHS
 180 */
 181static int iscsi_prep_ecdb_ahs(struct iscsi_task *task)
 182{
 183	struct scsi_cmnd *cmd = task->sc;
 184	unsigned rlen, pad_len;
 185	unsigned short ahslength;
 186	struct iscsi_ecdb_ahdr *ecdb_ahdr;
 187	int rc;
 188
 189	ecdb_ahdr = iscsi_next_hdr(task);
 190	rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
 191
 192	BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
 193	ahslength = rlen + sizeof(ecdb_ahdr->reserved);
 194
 195	pad_len = iscsi_padding(rlen);
 196
 197	rc = iscsi_add_hdr(task, sizeof(ecdb_ahdr->ahslength) +
 198	                   sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
 199	if (rc)
 200		return rc;
 201
 202	if (pad_len)
 203		memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
 204
 205	ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
 206	ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
 207	ecdb_ahdr->reserved = 0;
 208	memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
 209
 210	ISCSI_DBG_SESSION(task->conn->session,
 211			  "iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
 212		          "rlen %d pad_len %d ahs_length %d iscsi_headers_size "
 213		          "%u\n", cmd->cmd_len, rlen, pad_len, ahslength,
 214		          task->hdr_len);
 215	return 0;
 216}
 217
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 218/**
 219 * iscsi_check_tmf_restrictions - check if a task is affected by TMF
 220 * @task: iscsi task
 221 * @opcode: opcode to check for
 222 *
 223 * During TMF a task has to be checked if it's affected.
 224 * All unrelated I/O can be passed through, but I/O to the
 225 * affected LUN should be restricted.
 226 * If 'fast_abort' is set we won't be sending any I/O to the
 227 * affected LUN.
 228 * Otherwise the target is waiting for all TTTs to be completed,
 229 * so we have to send all outstanding Data-Out PDUs to the target.
 230 */
 231static int iscsi_check_tmf_restrictions(struct iscsi_task *task, int opcode)
 232{
 233	struct iscsi_session *session = task->conn->session;
 234	struct iscsi_tm *tmf = &session->tmhdr;
 235	u64 hdr_lun;
 236
 237	if (session->tmf_state == TMF_INITIAL)
 238		return 0;
 239
 240	if ((tmf->opcode & ISCSI_OPCODE_MASK) != ISCSI_OP_SCSI_TMFUNC)
 241		return 0;
 242
 243	switch (ISCSI_TM_FUNC_VALUE(tmf)) {
 244	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
 245		/*
 246		 * Allow PDUs for unrelated LUNs
 247		 */
 248		hdr_lun = scsilun_to_int(&tmf->lun);
 249		if (hdr_lun != task->sc->device->lun)
 250			return 0;
 251		fallthrough;
 252	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
 253		/*
 254		 * Fail all SCSI cmd PDUs
 255		 */
 256		if (opcode != ISCSI_OP_SCSI_DATA_OUT) {
 257			iscsi_session_printk(KERN_INFO, session,
 258					     "task [op %x itt 0x%x/0x%x] rejected.\n",
 259					     opcode, task->itt, task->hdr_itt);
 
 
 
 260			return -EACCES;
 261		}
 262		/*
 263		 * And also all data-out PDUs in response to R2T
 264		 * if fast_abort is set.
 265		 */
 266		if (session->fast_abort) {
 267			iscsi_session_printk(KERN_INFO, session,
 268					     "task [op %x itt 0x%x/0x%x] fast abort.\n",
 269					     opcode, task->itt, task->hdr_itt);
 
 
 270			return -EACCES;
 271		}
 272		break;
 273	case ISCSI_TM_FUNC_ABORT_TASK:
 274		/*
 275		 * the caller has already checked if the task
 276		 * they want to abort was in the pending queue so if
 277		 * we are here the cmd pdu has gone out already, and
 278		 * we will only hit this for data-outs
 279		 */
 280		if (opcode == ISCSI_OP_SCSI_DATA_OUT &&
 281		    task->hdr_itt == tmf->rtt) {
 282			ISCSI_DBG_SESSION(session,
 283					  "Preventing task %x/%x from sending "
 284					  "data-out due to abort task in "
 285					  "progress\n", task->itt,
 286					  task->hdr_itt);
 287			return -EACCES;
 288		}
 289		break;
 290	}
 291
 292	return 0;
 293}
 294
 295/**
 296 * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
 297 * @task: iscsi task
 298 *
 299 * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
 300 * fields like dlength or final based on how much data it sends
 301 */
 302static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
 303{
 304	struct iscsi_conn *conn = task->conn;
 305	struct iscsi_session *session = conn->session;
 306	struct scsi_cmnd *sc = task->sc;
 307	struct iscsi_scsi_req *hdr;
 308	unsigned hdrlength, cmd_len, transfer_length;
 309	itt_t itt;
 310	int rc;
 311
 312	rc = iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_CMD);
 313	if (rc)
 314		return rc;
 315
 316	if (conn->session->tt->alloc_pdu) {
 317		rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_CMD);
 318		if (rc)
 319			return rc;
 320	}
 321	hdr = (struct iscsi_scsi_req *)task->hdr;
 322	itt = hdr->itt;
 323	memset(hdr, 0, sizeof(*hdr));
 324
 325	if (session->tt->parse_pdu_itt)
 326		hdr->itt = task->hdr_itt = itt;
 327	else
 328		hdr->itt = task->hdr_itt = build_itt(task->itt,
 329						     task->conn->session->age);
 330	task->hdr_len = 0;
 331	rc = iscsi_add_hdr(task, sizeof(*hdr));
 332	if (rc)
 333		return rc;
 334	hdr->opcode = ISCSI_OP_SCSI_CMD;
 335	hdr->flags = ISCSI_ATTR_SIMPLE;
 336	int_to_scsilun(sc->device->lun, &hdr->lun);
 337	task->lun = hdr->lun;
 338	hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 339	cmd_len = sc->cmd_len;
 340	if (cmd_len < ISCSI_CDB_SIZE)
 341		memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
 342	else if (cmd_len > ISCSI_CDB_SIZE) {
 343		rc = iscsi_prep_ecdb_ahs(task);
 344		if (rc)
 345			return rc;
 346		cmd_len = ISCSI_CDB_SIZE;
 347	}
 348	memcpy(hdr->cdb, sc->cmnd, cmd_len);
 349
 350	task->imm_count = 0;
 351	if (scsi_get_prot_op(sc) != SCSI_PROT_NORMAL)
 352		task->protected = true;
 353
 354	transfer_length = scsi_transfer_length(sc);
 355	hdr->data_length = cpu_to_be32(transfer_length);
 
 356	if (sc->sc_data_direction == DMA_TO_DEVICE) {
 
 357		struct iscsi_r2t_info *r2t = &task->unsol_r2t;
 358
 
 359		hdr->flags |= ISCSI_FLAG_CMD_WRITE;
 360		/*
 361		 * Write counters:
 362		 *
 363		 *	imm_count	bytes to be sent right after
 364		 *			SCSI PDU Header
 365		 *
 366		 *	unsol_count	bytes(as Data-Out) to be sent
 367		 *			without	R2T ack right after
 368		 *			immediate data
 369		 *
 370		 *	r2t data_length bytes to be sent via R2T ack's
 371		 *
 372		 *      pad_count       bytes to be sent as zero-padding
 373		 */
 374		memset(r2t, 0, sizeof(*r2t));
 375
 376		if (session->imm_data_en) {
 377			if (transfer_length >= session->first_burst)
 378				task->imm_count = min(session->first_burst,
 379							conn->max_xmit_dlength);
 380			else
 381				task->imm_count = min(transfer_length,
 382						      conn->max_xmit_dlength);
 383			hton24(hdr->dlength, task->imm_count);
 384		} else
 385			zero_data(hdr->dlength);
 386
 387		if (!session->initial_r2t_en) {
 388			r2t->data_length = min(session->first_burst,
 389					       transfer_length) -
 390					       task->imm_count;
 391			r2t->data_offset = task->imm_count;
 392			r2t->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
 393			r2t->exp_statsn = cpu_to_be32(conn->exp_statsn);
 394		}
 395
 396		if (!task->unsol_r2t.data_length)
 397			/* No unsolicit Data-Out's */
 398			hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 399	} else {
 400		hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 401		zero_data(hdr->dlength);
 
 402
 403		if (sc->sc_data_direction == DMA_FROM_DEVICE)
 404			hdr->flags |= ISCSI_FLAG_CMD_READ;
 405	}
 406
 407	/* calculate size of additional header segments (AHSs) */
 408	hdrlength = task->hdr_len - sizeof(*hdr);
 409
 410	WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
 411	hdrlength /= ISCSI_PAD_LEN;
 412
 413	WARN_ON(hdrlength >= 256);
 414	hdr->hlength = hdrlength & 0xFF;
 415	hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
 416
 417	if (session->tt->init_task && session->tt->init_task(task))
 418		return -EIO;
 419
 420	task->state = ISCSI_TASK_RUNNING;
 421	session->cmdsn++;
 422
 423	conn->scsicmd_pdus_cnt++;
 424	ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
 425			  "itt 0x%x len %d cmdsn %d win %d]\n",
 
 426			  sc->sc_data_direction == DMA_TO_DEVICE ?
 427			  "write" : "read", conn->id, sc, sc->cmnd[0],
 428			  task->itt, transfer_length,
 
 429			  session->cmdsn,
 430			  session->max_cmdsn - session->exp_cmdsn + 1);
 431	return 0;
 432}
 433
 434/**
 435 * iscsi_free_task - free a task
 436 * @task: iscsi cmd task
 437 *
 438 * Must be called with session back_lock.
 439 * This function returns the scsi command to scsi-ml or cleans
 440 * up mgmt tasks then returns the task to the pool.
 441 */
 442static void iscsi_free_task(struct iscsi_task *task)
 443{
 444	struct iscsi_conn *conn = task->conn;
 445	struct iscsi_session *session = conn->session;
 446	struct scsi_cmnd *sc = task->sc;
 447	int oldstate = task->state;
 448
 449	ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
 450			  task->itt, task->state, task->sc);
 451
 452	session->tt->cleanup_task(task);
 453	task->state = ISCSI_TASK_FREE;
 454	task->sc = NULL;
 455	/*
 456	 * login task is preallocated so do not free
 457	 */
 458	if (conn->login_task == task)
 459		return;
 460
 461	kfifo_in(&session->cmdpool.queue, (void*)&task, sizeof(void*));
 462
 463	if (sc) {
 
 464		/* SCSI eh reuses commands to verify us */
 465		sc->SCp.ptr = NULL;
 466		/*
 467		 * queue command may call this to free the task, so
 468		 * it will decide how to return sc to scsi-ml.
 469		 */
 470		if (oldstate != ISCSI_TASK_REQUEUE_SCSIQ)
 471			sc->scsi_done(sc);
 472	}
 473}
 474
 475void __iscsi_get_task(struct iscsi_task *task)
 476{
 477	refcount_inc(&task->refcount);
 478}
 479EXPORT_SYMBOL_GPL(__iscsi_get_task);
 480
 481void __iscsi_put_task(struct iscsi_task *task)
 482{
 483	if (refcount_dec_and_test(&task->refcount))
 484		iscsi_free_task(task);
 485}
 486EXPORT_SYMBOL_GPL(__iscsi_put_task);
 487
 488void iscsi_put_task(struct iscsi_task *task)
 489{
 490	struct iscsi_session *session = task->conn->session;
 491
 492	/* regular RX path uses back_lock */
 493	spin_lock_bh(&session->back_lock);
 494	__iscsi_put_task(task);
 495	spin_unlock_bh(&session->back_lock);
 496}
 497EXPORT_SYMBOL_GPL(iscsi_put_task);
 498
 499/**
 500 * iscsi_complete_task - finish a task
 501 * @task: iscsi cmd task
 502 * @state: state to complete task with
 503 *
 504 * Must be called with session back_lock.
 505 */
 506static void iscsi_complete_task(struct iscsi_task *task, int state)
 507{
 508	struct iscsi_conn *conn = task->conn;
 509
 510	ISCSI_DBG_SESSION(conn->session,
 511			  "complete task itt 0x%x state %d sc %p\n",
 512			  task->itt, task->state, task->sc);
 513	if (task->state == ISCSI_TASK_COMPLETED ||
 514	    task->state == ISCSI_TASK_ABRT_TMF ||
 515	    task->state == ISCSI_TASK_ABRT_SESS_RECOV ||
 516	    task->state == ISCSI_TASK_REQUEUE_SCSIQ)
 517		return;
 518	WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
 519	task->state = state;
 520
 521	if (READ_ONCE(conn->ping_task) == task)
 522		WRITE_ONCE(conn->ping_task, NULL);
 
 
 
 
 
 
 523
 524	/* release get from queueing */
 525	__iscsi_put_task(task);
 526}
 527
 528/**
 529 * iscsi_complete_scsi_task - finish scsi task normally
 530 * @task: iscsi task for scsi cmd
 531 * @exp_cmdsn: expected cmd sn in cpu format
 532 * @max_cmdsn: max cmd sn in cpu format
 533 *
 534 * This is used when drivers do not need or cannot perform
 535 * lower level pdu processing.
 536 *
 537 * Called with session back_lock
 538 */
 539void iscsi_complete_scsi_task(struct iscsi_task *task,
 540			      uint32_t exp_cmdsn, uint32_t max_cmdsn)
 541{
 542	struct iscsi_conn *conn = task->conn;
 543
 544	ISCSI_DBG_SESSION(conn->session, "[itt 0x%x]\n", task->itt);
 545
 546	conn->last_recv = jiffies;
 547	__iscsi_update_cmdsn(conn->session, exp_cmdsn, max_cmdsn);
 548	iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 549}
 550EXPORT_SYMBOL_GPL(iscsi_complete_scsi_task);
 551
 552/*
 553 * Must be called with back and frwd lock
 554 */
 555static bool cleanup_queued_task(struct iscsi_task *task)
 556{
 557	struct iscsi_conn *conn = task->conn;
 558	bool early_complete = false;
 559
 560	/* Bad target might have completed task while it was still running */
 561	if (task->state == ISCSI_TASK_COMPLETED)
 562		early_complete = true;
 563
 564	if (!list_empty(&task->running)) {
 565		list_del_init(&task->running);
 566		/*
 567		 * If it's on a list but still running, this could be from
 568		 * a bad target sending a rsp early, cleanup from a TMF, or
 569		 * session recovery.
 570		 */
 571		if (task->state == ISCSI_TASK_RUNNING ||
 572		    task->state == ISCSI_TASK_COMPLETED)
 573			__iscsi_put_task(task);
 574	}
 575
 576	if (conn->session->running_aborted_task == task) {
 577		conn->session->running_aborted_task = NULL;
 578		__iscsi_put_task(task);
 579	}
 580
 581	if (conn->task == task) {
 582		conn->task = NULL;
 583		__iscsi_put_task(task);
 584	}
 585
 586	return early_complete;
 587}
 588
 589/*
 590 * session frwd lock must be held and if not called for a task that is still
 591 * pending or from the xmit thread, then xmit thread must be suspended
 
 592 */
 593static void fail_scsi_task(struct iscsi_task *task, int err)
 594{
 595	struct iscsi_conn *conn = task->conn;
 596	struct scsi_cmnd *sc;
 597	int state;
 598
 599	spin_lock_bh(&conn->session->back_lock);
 600	if (cleanup_queued_task(task)) {
 601		spin_unlock_bh(&conn->session->back_lock);
 
 
 
 
 602		return;
 603	}
 604
 605	if (task->state == ISCSI_TASK_PENDING) {
 606		/*
 607		 * cmd never made it to the xmit thread, so we should not count
 608		 * the cmd in the sequencing
 609		 */
 610		conn->session->queued_cmdsn--;
 611		/* it was never sent so just complete like normal */
 612		state = ISCSI_TASK_COMPLETED;
 613	} else if (err == DID_TRANSPORT_DISRUPTED)
 614		state = ISCSI_TASK_ABRT_SESS_RECOV;
 615	else
 616		state = ISCSI_TASK_ABRT_TMF;
 617
 618	sc = task->sc;
 619	sc->result = err << 16;
 620	scsi_set_resid(sc, scsi_bufflen(sc));
 
 
 
 
 
 
 621	iscsi_complete_task(task, state);
 622	spin_unlock_bh(&conn->session->back_lock);
 623}
 624
 625static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
 626				struct iscsi_task *task)
 627{
 628	struct iscsi_session *session = conn->session;
 629	struct iscsi_hdr *hdr = task->hdr;
 630	struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 631	uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
 632
 633	if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
 634		return -ENOTCONN;
 635
 636	if (opcode != ISCSI_OP_LOGIN && opcode != ISCSI_OP_TEXT)
 637		nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 638	/*
 639	 * pre-format CmdSN for outgoing PDU.
 640	 */
 641	nop->cmdsn = cpu_to_be32(session->cmdsn);
 642	if (hdr->itt != RESERVED_ITT) {
 643		/*
 644		 * TODO: We always use immediate for normal session pdus.
 645		 * If we start to send tmfs or nops as non-immediate then
 646		 * we should start checking the cmdsn numbers for mgmt tasks.
 647		 *
 648		 * During discovery sessions iscsid sends TEXT as non immediate,
 649		 * but we always only send one PDU at a time.
 650		 */
 651		if (conn->c_stage == ISCSI_CONN_STARTED &&
 652		    !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
 653			session->queued_cmdsn++;
 654			session->cmdsn++;
 655		}
 656	}
 657
 658	if (session->tt->init_task && session->tt->init_task(task))
 659		return -EIO;
 660
 661	if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
 662		session->state = ISCSI_STATE_LOGGING_OUT;
 663
 664	task->state = ISCSI_TASK_RUNNING;
 665	ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x "
 666			  "datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK,
 667			  hdr->itt, task->data_count);
 668	return 0;
 669}
 670
 671static struct iscsi_task *
 672__iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 673		      char *data, uint32_t data_size)
 674{
 675	struct iscsi_session *session = conn->session;
 676	struct iscsi_host *ihost = shost_priv(session->host);
 677	uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
 678	struct iscsi_task *task;
 679	itt_t itt;
 680
 681	if (session->state == ISCSI_STATE_TERMINATE)
 682		return NULL;
 683
 684	if (opcode == ISCSI_OP_LOGIN || opcode == ISCSI_OP_TEXT) {
 685		/*
 686		 * Login and Text are sent serially, in
 687		 * request-followed-by-response sequence.
 688		 * Same task can be used. Same ITT must be used.
 689		 * Note that login_task is preallocated at conn_create().
 690		 */
 691		if (conn->login_task->state != ISCSI_TASK_FREE) {
 692			iscsi_conn_printk(KERN_ERR, conn, "Login/Text in "
 693					  "progress. Cannot start new task.\n");
 694			return NULL;
 695		}
 696
 697		if (data_size > ISCSI_DEF_MAX_RECV_SEG_LEN) {
 698			iscsi_conn_printk(KERN_ERR, conn, "Invalid buffer len of %u for login task. Max len is %u\n", data_size, ISCSI_DEF_MAX_RECV_SEG_LEN);
 699			return NULL;
 700		}
 701
 702		task = conn->login_task;
 703	} else {
 704		if (session->state != ISCSI_STATE_LOGGED_IN)
 705			return NULL;
 706
 707		if (data_size != 0) {
 708			iscsi_conn_printk(KERN_ERR, conn, "Can not send data buffer of len %u for op 0x%x\n", data_size, opcode);
 709			return NULL;
 710		}
 711
 712		BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 713		BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 714
 715		if (!kfifo_out(&session->cmdpool.queue,
 716				 (void*)&task, sizeof(void*)))
 717			return NULL;
 718	}
 719	/*
 720	 * released in complete pdu for task we expect a response for, and
 721	 * released by the lld when it has transmitted the task for
 722	 * pdus we do not expect a response for.
 723	 */
 724	refcount_set(&task->refcount, 1);
 725	task->conn = conn;
 726	task->sc = NULL;
 727	INIT_LIST_HEAD(&task->running);
 728	task->state = ISCSI_TASK_PENDING;
 729
 730	if (data_size) {
 731		memcpy(task->data, data, data_size);
 732		task->data_count = data_size;
 733	} else
 734		task->data_count = 0;
 735
 736	if (conn->session->tt->alloc_pdu) {
 737		if (conn->session->tt->alloc_pdu(task, hdr->opcode)) {
 738			iscsi_conn_printk(KERN_ERR, conn, "Could not allocate "
 739					 "pdu for mgmt task.\n");
 740			goto free_task;
 741		}
 742	}
 743
 744	itt = task->hdr->itt;
 745	task->hdr_len = sizeof(struct iscsi_hdr);
 746	memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr));
 747
 748	if (hdr->itt != RESERVED_ITT) {
 749		if (session->tt->parse_pdu_itt)
 750			task->hdr->itt = itt;
 751		else
 752			task->hdr->itt = build_itt(task->itt,
 753						   task->conn->session->age);
 754	}
 755
 756	if (unlikely(READ_ONCE(conn->ping_task) == INVALID_SCSI_TASK))
 757		WRITE_ONCE(conn->ping_task, task);
 758
 759	if (!ihost->workq) {
 760		if (iscsi_prep_mgmt_task(conn, task))
 761			goto free_task;
 762
 763		if (session->tt->xmit_task(task))
 764			goto free_task;
 765	} else {
 766		list_add_tail(&task->running, &conn->mgmtqueue);
 767		iscsi_conn_queue_work(conn);
 768	}
 769
 770	return task;
 771
 772free_task:
 773	/* regular RX path uses back_lock */
 774	spin_lock(&session->back_lock);
 775	__iscsi_put_task(task);
 776	spin_unlock(&session->back_lock);
 777	return NULL;
 778}
 779
 780int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 781			char *data, uint32_t data_size)
 782{
 783	struct iscsi_conn *conn = cls_conn->dd_data;
 784	struct iscsi_session *session = conn->session;
 785	int err = 0;
 786
 787	spin_lock_bh(&session->frwd_lock);
 788	if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
 789		err = -EPERM;
 790	spin_unlock_bh(&session->frwd_lock);
 791	return err;
 792}
 793EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 794
 795/**
 796 * iscsi_scsi_cmd_rsp - SCSI Command Response processing
 797 * @conn: iscsi connection
 798 * @hdr: iscsi header
 799 * @task: scsi command task
 800 * @data: cmd data buffer
 801 * @datalen: len of buffer
 802 *
 803 * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
 804 * then completes the command and task. called under back_lock
 805 **/
 806static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 807			       struct iscsi_task *task, char *data,
 808			       int datalen)
 809{
 810	struct iscsi_scsi_rsp *rhdr = (struct iscsi_scsi_rsp *)hdr;
 811	struct iscsi_session *session = conn->session;
 812	struct scsi_cmnd *sc = task->sc;
 813
 814	iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
 815	conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 816
 817	sc->result = (DID_OK << 16) | rhdr->cmd_status;
 818
 819	if (task->protected) {
 820		sector_t sector;
 821		u8 ascq;
 822
 823		/**
 824		 * Transports that didn't implement check_protection
 825		 * callback but still published T10-PI support to scsi-mid
 826		 * deserve this BUG_ON.
 827		 **/
 828		BUG_ON(!session->tt->check_protection);
 829
 830		ascq = session->tt->check_protection(task, &sector);
 831		if (ascq) {
 832			scsi_build_sense(sc, 1, ILLEGAL_REQUEST, 0x10, ascq);
 833			scsi_set_sense_information(sc->sense_buffer,
 834						   SCSI_SENSE_BUFFERSIZE,
 835						   sector);
 836			goto out;
 837		}
 838	}
 839
 840	if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
 841		sc->result = DID_ERROR << 16;
 842		goto out;
 843	}
 844
 845	if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
 846		uint16_t senselen;
 847
 848		if (datalen < 2) {
 849invalid_datalen:
 850			iscsi_conn_printk(KERN_ERR,  conn,
 851					 "Got CHECK_CONDITION but invalid data "
 852					 "buffer size of %d\n", datalen);
 853			sc->result = DID_BAD_TARGET << 16;
 854			goto out;
 855		}
 856
 857		senselen = get_unaligned_be16(data);
 858		if (datalen < senselen)
 859			goto invalid_datalen;
 860
 861		memcpy(sc->sense_buffer, data + 2,
 862		       min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 863		ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n",
 864				  min_t(uint16_t, senselen,
 865				  SCSI_SENSE_BUFFERSIZE));
 866	}
 867
 868	if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
 869			   ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
 870		sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 
 
 
 
 
 
 
 871	}
 872
 873	if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
 874	                   ISCSI_FLAG_CMD_OVERFLOW)) {
 875		int res_count = be32_to_cpu(rhdr->residual_count);
 876
 877		if (res_count > 0 &&
 878		    (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 879		     res_count <= scsi_bufflen(sc)))
 880			/* write side for bidi or uni-io set_resid */
 881			scsi_set_resid(sc, res_count);
 882		else
 883			sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 884	}
 885out:
 886	ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n",
 887			  sc, sc->result, task->itt);
 888	conn->scsirsp_pdus_cnt++;
 889	iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 890}
 891
 892/**
 893 * iscsi_data_in_rsp - SCSI Data-In Response processing
 894 * @conn: iscsi connection
 895 * @hdr:  iscsi pdu
 896 * @task: scsi command task
 897 *
 898 * iscsi_data_in_rsp sets up the scsi_cmnd fields based on the data received
 899 * then completes the command and task. called under back_lock
 900 **/
 901static void
 902iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 903		  struct iscsi_task *task)
 904{
 905	struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr;
 906	struct scsi_cmnd *sc = task->sc;
 907
 908	if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
 909		return;
 910
 911	iscsi_update_cmdsn(conn->session, (struct iscsi_nopin *)hdr);
 912	sc->result = (DID_OK << 16) | rhdr->cmd_status;
 913	conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 914	if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
 915	                   ISCSI_FLAG_DATA_OVERFLOW)) {
 916		int res_count = be32_to_cpu(rhdr->residual_count);
 917
 918		if (res_count > 0 &&
 919		    (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 920		     res_count <= sc->sdb.length))
 921			scsi_set_resid(sc, res_count);
 922		else
 923			sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 924	}
 925
 926	ISCSI_DBG_SESSION(conn->session, "data in with status done "
 927			  "[sc %p res %d itt 0x%x]\n",
 928			  sc, sc->result, task->itt);
 929	conn->scsirsp_pdus_cnt++;
 930	iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 931}
 932
 933static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 934{
 935	struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
 936	struct iscsi_session *session = conn->session;
 937
 938	conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 939	conn->tmfrsp_pdus_cnt++;
 940
 941	if (session->tmf_state != TMF_QUEUED)
 942		return;
 943
 944	if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
 945		session->tmf_state = TMF_SUCCESS;
 946	else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
 947		session->tmf_state = TMF_NOT_FOUND;
 948	else
 949		session->tmf_state = TMF_FAILED;
 950	wake_up(&session->ehwait);
 951}
 952
 953static int iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
 954{
 955        struct iscsi_nopout hdr;
 956	struct iscsi_task *task;
 957
 958	if (!rhdr) {
 959		if (READ_ONCE(conn->ping_task))
 960			return -EINVAL;
 961		WRITE_ONCE(conn->ping_task, INVALID_SCSI_TASK);
 962	}
 963
 964	memset(&hdr, 0, sizeof(struct iscsi_nopout));
 965	hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
 966	hdr.flags = ISCSI_FLAG_CMD_FINAL;
 967
 968	if (rhdr) {
 969		hdr.lun = rhdr->lun;
 970		hdr.ttt = rhdr->ttt;
 971		hdr.itt = RESERVED_ITT;
 972	} else
 973		hdr.ttt = RESERVED_ITT;
 974
 975	task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
 976	if (!task) {
 977		if (!rhdr)
 978			WRITE_ONCE(conn->ping_task, NULL);
 979		iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
 980		return -EIO;
 981	} else if (!rhdr) {
 982		/* only track our nops */
 
 983		conn->last_ping = jiffies;
 984	}
 985
 986	return 0;
 987}
 988
 989/**
 990 * iscsi_nop_out_rsp - SCSI NOP Response processing
 991 * @task: scsi command task
 992 * @nop: the nop structure
 993 * @data: where to put the data
 994 * @datalen: length of data
 995 *
 996 * iscsi_nop_out_rsp handles nop response from use or
 997 * from user space. called under back_lock
 998 **/
 999static int iscsi_nop_out_rsp(struct iscsi_task *task,
1000			     struct iscsi_nopin *nop, char *data, int datalen)
1001{
1002	struct iscsi_conn *conn = task->conn;
1003	int rc = 0;
1004
1005	if (READ_ONCE(conn->ping_task) != task) {
1006		/*
1007		 * If this is not in response to one of our
1008		 * nops then it must be from userspace.
1009		 */
1010		if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop,
1011				   data, datalen))
1012			rc = ISCSI_ERR_CONN_FAILED;
1013	} else
1014		mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
1015	iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1016	return rc;
1017}
1018
1019static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1020			       char *data, int datalen)
1021{
1022	struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
1023	struct iscsi_hdr rejected_pdu;
1024	int opcode, rc = 0;
1025
1026	conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
1027
1028	if (ntoh24(reject->dlength) > datalen ||
1029	    ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) {
1030		iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected "
1031				  "pdu. Invalid data length (pdu dlength "
1032				  "%u, datalen %d\n", ntoh24(reject->dlength),
1033				  datalen);
1034		return ISCSI_ERR_PROTO;
1035	}
1036	memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
1037	opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK;
1038
1039	switch (reject->reason) {
1040	case ISCSI_REASON_DATA_DIGEST_ERROR:
1041		iscsi_conn_printk(KERN_ERR, conn,
1042				  "pdu (op 0x%x itt 0x%x) rejected "
1043				  "due to DataDigest error.\n",
1044				  opcode, rejected_pdu.itt);
1045		break;
1046	case ISCSI_REASON_IMM_CMD_REJECT:
1047		iscsi_conn_printk(KERN_ERR, conn,
1048				  "pdu (op 0x%x itt 0x%x) rejected. Too many "
1049				  "immediate commands.\n",
1050				  opcode, rejected_pdu.itt);
1051		/*
1052		 * We only send one TMF at a time so if the target could not
1053		 * handle it, then it should get fixed (RFC mandates that
1054		 * a target can handle one immediate TMF per conn).
1055		 *
1056		 * For nops-outs, we could have sent more than one if
1057		 * the target is sending us lots of nop-ins
1058		 */
1059		if (opcode != ISCSI_OP_NOOP_OUT)
1060			return 0;
1061
1062		if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG)) {
1063			/*
1064			 * nop-out in response to target's nop-out rejected.
1065			 * Just resend.
1066			 */
1067			/* In RX path we are under back lock */
1068			spin_unlock(&conn->session->back_lock);
1069			spin_lock(&conn->session->frwd_lock);
1070			iscsi_send_nopout(conn,
1071					  (struct iscsi_nopin*)&rejected_pdu);
1072			spin_unlock(&conn->session->frwd_lock);
1073			spin_lock(&conn->session->back_lock);
1074		} else {
1075			struct iscsi_task *task;
1076			/*
1077			 * Our nop as ping got dropped. We know the target
1078			 * and transport are ok so just clean up
1079			 */
1080			task = iscsi_itt_to_task(conn, rejected_pdu.itt);
1081			if (!task) {
1082				iscsi_conn_printk(KERN_ERR, conn,
1083						 "Invalid pdu reject. Could "
1084						 "not lookup rejected task.\n");
1085				rc = ISCSI_ERR_BAD_ITT;
1086			} else
1087				rc = iscsi_nop_out_rsp(task,
1088					(struct iscsi_nopin*)&rejected_pdu,
1089					NULL, 0);
1090		}
1091		break;
1092	default:
1093		iscsi_conn_printk(KERN_ERR, conn,
1094				  "pdu (op 0x%x itt 0x%x) rejected. Reason "
1095				  "code 0x%x\n", rejected_pdu.opcode,
1096				  rejected_pdu.itt, reject->reason);
1097		break;
1098	}
1099	return rc;
1100}
1101
1102/**
1103 * iscsi_itt_to_task - look up task by itt
1104 * @conn: iscsi connection
1105 * @itt: itt
1106 *
1107 * This should be used for mgmt tasks like login and nops, or if
1108 * the LDD's itt space does not include the session age.
1109 *
1110 * The session back_lock must be held.
1111 */
1112struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
1113{
1114	struct iscsi_session *session = conn->session;
1115	int i;
1116
1117	if (itt == RESERVED_ITT)
1118		return NULL;
1119
1120	if (session->tt->parse_pdu_itt)
1121		session->tt->parse_pdu_itt(conn, itt, &i, NULL);
1122	else
1123		i = get_itt(itt);
1124	if (i >= session->cmds_max)
1125		return NULL;
1126
1127	return session->cmds[i];
1128}
1129EXPORT_SYMBOL_GPL(iscsi_itt_to_task);
1130
1131/**
1132 * __iscsi_complete_pdu - complete pdu
1133 * @conn: iscsi conn
1134 * @hdr: iscsi header
1135 * @data: data buffer
1136 * @datalen: len of data buffer
1137 *
1138 * Completes pdu processing by freeing any resources allocated at
1139 * queuecommand or send generic. session back_lock must be held and verify
1140 * itt must have been called.
1141 */
1142int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1143			 char *data, int datalen)
1144{
1145	struct iscsi_session *session = conn->session;
1146	int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
1147	struct iscsi_task *task;
1148	uint32_t itt;
1149
1150	conn->last_recv = jiffies;
1151	rc = iscsi_verify_itt(conn, hdr->itt);
1152	if (rc)
1153		return rc;
1154
1155	if (hdr->itt != RESERVED_ITT)
1156		itt = get_itt(hdr->itt);
1157	else
1158		itt = ~0U;
1159
1160	ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n",
1161			  opcode, conn->id, itt, datalen);
1162
1163	if (itt == ~0U) {
1164		iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1165
1166		switch(opcode) {
1167		case ISCSI_OP_NOOP_IN:
1168			if (datalen) {
1169				rc = ISCSI_ERR_PROTO;
1170				break;
1171			}
1172
1173			if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
1174				break;
1175
1176			/* In RX path we are under back lock */
1177			spin_unlock(&session->back_lock);
1178			spin_lock(&session->frwd_lock);
1179			iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
1180			spin_unlock(&session->frwd_lock);
1181			spin_lock(&session->back_lock);
1182			break;
1183		case ISCSI_OP_REJECT:
1184			rc = iscsi_handle_reject(conn, hdr, data, datalen);
1185			break;
1186		case ISCSI_OP_ASYNC_EVENT:
1187			conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1188			if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1189				rc = ISCSI_ERR_CONN_FAILED;
1190			break;
1191		default:
1192			rc = ISCSI_ERR_BAD_OPCODE;
1193			break;
1194		}
1195		goto out;
1196	}
1197
1198	switch(opcode) {
1199	case ISCSI_OP_SCSI_CMD_RSP:
1200	case ISCSI_OP_SCSI_DATA_IN:
1201		task = iscsi_itt_to_ctask(conn, hdr->itt);
1202		if (!task)
1203			return ISCSI_ERR_BAD_ITT;
1204		task->last_xfer = jiffies;
1205		break;
1206	case ISCSI_OP_R2T:
1207		/*
1208		 * LLD handles R2Ts if they need to.
1209		 */
1210		return 0;
1211	case ISCSI_OP_LOGOUT_RSP:
1212	case ISCSI_OP_LOGIN_RSP:
1213	case ISCSI_OP_TEXT_RSP:
1214	case ISCSI_OP_SCSI_TMFUNC_RSP:
1215	case ISCSI_OP_NOOP_IN:
1216		task = iscsi_itt_to_task(conn, hdr->itt);
1217		if (!task)
1218			return ISCSI_ERR_BAD_ITT;
1219		break;
1220	default:
1221		return ISCSI_ERR_BAD_OPCODE;
1222	}
1223
1224	switch(opcode) {
1225	case ISCSI_OP_SCSI_CMD_RSP:
1226		iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
1227		break;
1228	case ISCSI_OP_SCSI_DATA_IN:
1229		iscsi_data_in_rsp(conn, hdr, task);
1230		break;
1231	case ISCSI_OP_LOGOUT_RSP:
1232		iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1233		if (datalen) {
1234			rc = ISCSI_ERR_PROTO;
1235			break;
1236		}
1237		conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1238		goto recv_pdu;
1239	case ISCSI_OP_LOGIN_RSP:
1240	case ISCSI_OP_TEXT_RSP:
1241		iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1242		/*
1243		 * login related PDU's exp_statsn is handled in
1244		 * userspace
1245		 */
1246		goto recv_pdu;
1247	case ISCSI_OP_SCSI_TMFUNC_RSP:
1248		iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1249		if (datalen) {
1250			rc = ISCSI_ERR_PROTO;
1251			break;
1252		}
1253
1254		iscsi_tmf_rsp(conn, hdr);
1255		iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1256		break;
1257	case ISCSI_OP_NOOP_IN:
1258		iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1259		if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
1260			rc = ISCSI_ERR_PROTO;
1261			break;
1262		}
1263		conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1264
1265		rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr,
1266				       data, datalen);
1267		break;
1268	default:
1269		rc = ISCSI_ERR_BAD_OPCODE;
1270		break;
1271	}
1272
1273out:
1274	return rc;
1275recv_pdu:
1276	if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1277		rc = ISCSI_ERR_CONN_FAILED;
1278	iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1279	return rc;
1280}
1281EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
1282
1283int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1284		       char *data, int datalen)
1285{
1286	int rc;
1287
1288	spin_lock(&conn->session->back_lock);
1289	rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
1290	spin_unlock(&conn->session->back_lock);
1291	return rc;
1292}
1293EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
1294
1295int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
1296{
1297	struct iscsi_session *session = conn->session;
1298	int age = 0, i = 0;
1299
1300	if (itt == RESERVED_ITT)
1301		return 0;
1302
1303	if (session->tt->parse_pdu_itt)
1304		session->tt->parse_pdu_itt(conn, itt, &i, &age);
1305	else {
1306		i = get_itt(itt);
1307		age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK;
1308	}
1309
1310	if (age != session->age) {
1311		iscsi_conn_printk(KERN_ERR, conn,
1312				  "received itt %x expected session age (%x)\n",
1313				  (__force u32)itt, session->age);
1314		return ISCSI_ERR_BAD_ITT;
1315	}
1316
1317	if (i >= session->cmds_max) {
1318		iscsi_conn_printk(KERN_ERR, conn,
1319				  "received invalid itt index %u (max cmds "
1320				   "%u.\n", i, session->cmds_max);
1321		return ISCSI_ERR_BAD_ITT;
1322	}
1323	return 0;
1324}
1325EXPORT_SYMBOL_GPL(iscsi_verify_itt);
1326
1327/**
1328 * iscsi_itt_to_ctask - look up ctask by itt
1329 * @conn: iscsi connection
1330 * @itt: itt
1331 *
1332 * This should be used for cmd tasks.
1333 *
1334 * The session back_lock must be held.
1335 */
1336struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
1337{
1338	struct iscsi_task *task;
1339
1340	if (iscsi_verify_itt(conn, itt))
1341		return NULL;
1342
1343	task = iscsi_itt_to_task(conn, itt);
1344	if (!task || !task->sc)
1345		return NULL;
1346
1347	if (task->sc->SCp.phase != conn->session->age) {
1348		iscsi_session_printk(KERN_ERR, conn->session,
1349				  "task's session age %d, expected %d\n",
1350				  task->sc->SCp.phase, conn->session->age);
1351		return NULL;
1352	}
1353
1354	return task;
1355}
1356EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
1357
1358void iscsi_session_failure(struct iscsi_session *session,
1359			   enum iscsi_err err)
1360{
1361	struct iscsi_conn *conn;
 
1362
1363	spin_lock_bh(&session->frwd_lock);
1364	conn = session->leadconn;
1365	if (session->state == ISCSI_STATE_TERMINATE || !conn) {
1366		spin_unlock_bh(&session->frwd_lock);
1367		return;
1368	}
1369
1370	iscsi_get_conn(conn->cls_conn);
1371	spin_unlock_bh(&session->frwd_lock);
 
 
1372	/*
1373	 * if the host is being removed bypass the connection
1374	 * recovery initialization because we are going to kill
1375	 * the session.
1376	 */
1377	if (err == ISCSI_ERR_INVALID_HOST)
1378		iscsi_conn_error_event(conn->cls_conn, err);
1379	else
1380		iscsi_conn_failure(conn, err);
1381	iscsi_put_conn(conn->cls_conn);
1382}
1383EXPORT_SYMBOL_GPL(iscsi_session_failure);
1384
1385static bool iscsi_set_conn_failed(struct iscsi_conn *conn)
1386{
1387	struct iscsi_session *session = conn->session;
1388
1389	if (session->state == ISCSI_STATE_FAILED)
1390		return false;
 
 
 
1391
1392	if (conn->stop_stage == 0)
1393		session->state = ISCSI_STATE_FAILED;
 
1394
1395	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1396	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1397	return true;
1398}
1399
1400void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
1401{
1402	struct iscsi_session *session = conn->session;
1403	bool needs_evt;
1404
1405	spin_lock_bh(&session->frwd_lock);
1406	needs_evt = iscsi_set_conn_failed(conn);
1407	spin_unlock_bh(&session->frwd_lock);
1408
1409	if (needs_evt)
1410		iscsi_conn_error_event(conn->cls_conn, err);
1411}
1412EXPORT_SYMBOL_GPL(iscsi_conn_failure);
1413
1414static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
1415{
1416	struct iscsi_session *session = conn->session;
1417
1418	/*
1419	 * Check for iSCSI window and take care of CmdSN wrap-around
1420	 */
1421	if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
1422		ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn "
1423				  "%u MaxCmdSN %u CmdSN %u/%u\n",
1424				  session->exp_cmdsn, session->max_cmdsn,
1425				  session->cmdsn, session->queued_cmdsn);
1426		return -ENOSPC;
1427	}
1428	return 0;
1429}
1430
1431static int iscsi_xmit_task(struct iscsi_conn *conn, struct iscsi_task *task,
1432			   bool was_requeue)
1433{
 
1434	int rc;
1435
1436	spin_lock_bh(&conn->session->back_lock);
1437
1438	if (!conn->task) {
1439		/* Take a ref so we can access it after xmit_task() */
1440		__iscsi_get_task(task);
1441	} else {
1442		/* Already have a ref from when we failed to send it last call */
1443		conn->task = NULL;
1444	}
1445
1446	/*
1447	 * If this was a requeue for a R2T we have an extra ref on the task in
1448	 * case a bad target sends a cmd rsp before we have handled the task.
1449	 */
1450	if (was_requeue)
1451		__iscsi_put_task(task);
1452
1453	/*
1454	 * Do this after dropping the extra ref because if this was a requeue
1455	 * it's removed from that list and cleanup_queued_task would miss it.
1456	 */
1457	if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1458		/*
1459		 * Save the task and ref in case we weren't cleaning up this
1460		 * task and get woken up again.
1461		 */
1462		conn->task = task;
1463		spin_unlock_bh(&conn->session->back_lock);
1464		return -ENODATA;
1465	}
1466	spin_unlock_bh(&conn->session->back_lock);
1467
1468	spin_unlock_bh(&conn->session->frwd_lock);
 
1469	rc = conn->session->tt->xmit_task(task);
1470	spin_lock_bh(&conn->session->frwd_lock);
1471	if (!rc) {
1472		/* done with this task */
1473		task->last_xfer = jiffies;
 
1474	}
1475	/* regular RX path uses back_lock */
1476	spin_lock(&conn->session->back_lock);
1477	if (rc && task->state == ISCSI_TASK_RUNNING) {
1478		/*
1479		 * get an extra ref that is released next time we access it
1480		 * as conn->task above.
1481		 */
1482		__iscsi_get_task(task);
1483		conn->task = task;
1484	}
1485
1486	__iscsi_put_task(task);
1487	spin_unlock(&conn->session->back_lock);
1488	return rc;
1489}
1490
1491/**
1492 * iscsi_requeue_task - requeue task to run from session workqueue
1493 * @task: task to requeue
1494 *
1495 * Callers must have taken a ref to the task that is going to be requeued.
 
 
1496 */
1497void iscsi_requeue_task(struct iscsi_task *task)
1498{
1499	struct iscsi_conn *conn = task->conn;
1500
1501	/*
1502	 * this may be on the requeue list already if the xmit_task callout
1503	 * is handling the r2ts while we are adding new ones
1504	 */
1505	spin_lock_bh(&conn->session->frwd_lock);
1506	if (list_empty(&task->running)) {
1507		list_add_tail(&task->running, &conn->requeue);
1508	} else {
1509		/*
1510		 * Don't need the extra ref since it's already requeued and
1511		 * has a ref.
1512		 */
1513		iscsi_put_task(task);
1514	}
1515	iscsi_conn_queue_work(conn);
1516	spin_unlock_bh(&conn->session->frwd_lock);
1517}
1518EXPORT_SYMBOL_GPL(iscsi_requeue_task);
1519
1520/**
1521 * iscsi_data_xmit - xmit any command into the scheduled connection
1522 * @conn: iscsi connection
1523 *
1524 * Notes:
1525 *	The function can return -EAGAIN in which case the caller must
1526 *	re-schedule it again later or recover. '0' return code means
1527 *	successful xmit.
1528 **/
1529static int iscsi_data_xmit(struct iscsi_conn *conn)
1530{
1531	struct iscsi_task *task;
1532	int rc = 0;
1533
1534	spin_lock_bh(&conn->session->frwd_lock);
1535	if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1536		ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n");
1537		spin_unlock_bh(&conn->session->frwd_lock);
1538		return -ENODATA;
1539	}
1540
1541	if (conn->task) {
1542		rc = iscsi_xmit_task(conn, conn->task, false);
1543	        if (rc)
1544		        goto done;
1545	}
1546
1547	/*
1548	 * process mgmt pdus like nops before commands since we should
1549	 * only have one nop-out as a ping from us and targets should not
1550	 * overflow us with nop-ins
1551	 */
1552check_mgmt:
1553	while (!list_empty(&conn->mgmtqueue)) {
1554		task = list_entry(conn->mgmtqueue.next, struct iscsi_task,
1555				  running);
1556		list_del_init(&task->running);
1557		if (iscsi_prep_mgmt_task(conn, task)) {
1558			/* regular RX path uses back_lock */
1559			spin_lock_bh(&conn->session->back_lock);
1560			__iscsi_put_task(task);
1561			spin_unlock_bh(&conn->session->back_lock);
1562			continue;
1563		}
1564		rc = iscsi_xmit_task(conn, task, false);
1565		if (rc)
1566			goto done;
1567	}
1568
1569	/* process pending command queue */
1570	while (!list_empty(&conn->cmdqueue)) {
1571		task = list_entry(conn->cmdqueue.next, struct iscsi_task,
1572				  running);
1573		list_del_init(&task->running);
1574		if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1575			fail_scsi_task(task, DID_IMM_RETRY);
1576			continue;
1577		}
1578		rc = iscsi_prep_scsi_cmd_pdu(task);
1579		if (rc) {
1580			if (rc == -ENOMEM || rc == -EACCES)
1581				fail_scsi_task(task, DID_IMM_RETRY);
1582			else
1583				fail_scsi_task(task, DID_ABORT);
 
 
 
1584			continue;
1585		}
1586		rc = iscsi_xmit_task(conn, task, false);
1587		if (rc)
1588			goto done;
1589		/*
1590		 * we could continuously get new task requests so
1591		 * we need to check the mgmt queue for nops that need to
1592		 * be sent to aviod starvation
1593		 */
1594		if (!list_empty(&conn->mgmtqueue))
1595			goto check_mgmt;
1596	}
1597
1598	while (!list_empty(&conn->requeue)) {
1599		/*
1600		 * we always do fastlogout - conn stop code will clean up.
1601		 */
1602		if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1603			break;
1604
1605		task = list_entry(conn->requeue.next, struct iscsi_task,
1606				  running);
1607
1608		if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT))
1609			break;
1610
1611		list_del_init(&task->running);
1612		rc = iscsi_xmit_task(conn, task, true);
 
 
1613		if (rc)
1614			goto done;
1615		if (!list_empty(&conn->mgmtqueue))
1616			goto check_mgmt;
1617	}
1618	spin_unlock_bh(&conn->session->frwd_lock);
1619	return -ENODATA;
1620
1621done:
1622	spin_unlock_bh(&conn->session->frwd_lock);
1623	return rc;
1624}
1625
1626static void iscsi_xmitworker(struct work_struct *work)
1627{
1628	struct iscsi_conn *conn =
1629		container_of(work, struct iscsi_conn, xmitwork);
1630	int rc;
1631	/*
1632	 * serialize Xmit worker on a per-connection basis.
1633	 */
1634	do {
1635		rc = iscsi_data_xmit(conn);
1636	} while (rc >= 0 || rc == -EAGAIN);
1637}
1638
1639static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
1640						  struct scsi_cmnd *sc)
1641{
1642	struct iscsi_task *task;
1643
1644	if (!kfifo_out(&conn->session->cmdpool.queue,
1645			 (void *) &task, sizeof(void *)))
1646		return NULL;
1647
1648	sc->SCp.phase = conn->session->age;
1649	sc->SCp.ptr = (char *) task;
1650
1651	refcount_set(&task->refcount, 1);
1652	task->state = ISCSI_TASK_PENDING;
1653	task->conn = conn;
1654	task->sc = sc;
1655	task->have_checked_conn = false;
1656	task->last_timeout = jiffies;
1657	task->last_xfer = jiffies;
1658	task->protected = false;
1659	INIT_LIST_HEAD(&task->running);
1660	return task;
1661}
1662
1663enum {
1664	FAILURE_BAD_HOST = 1,
1665	FAILURE_SESSION_FAILED,
1666	FAILURE_SESSION_FREED,
1667	FAILURE_WINDOW_CLOSED,
1668	FAILURE_OOM,
1669	FAILURE_SESSION_TERMINATE,
1670	FAILURE_SESSION_IN_RECOVERY,
1671	FAILURE_SESSION_RECOVERY_TIMEOUT,
1672	FAILURE_SESSION_LOGGING_OUT,
1673	FAILURE_SESSION_NOT_READY,
1674};
1675
1676int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
1677{
1678	struct iscsi_cls_session *cls_session;
1679	struct iscsi_host *ihost;
1680	int reason = 0;
1681	struct iscsi_session *session;
1682	struct iscsi_conn *conn;
1683	struct iscsi_task *task = NULL;
1684
1685	sc->result = 0;
1686	sc->SCp.ptr = NULL;
1687
1688	ihost = shost_priv(host);
1689
1690	cls_session = starget_to_session(scsi_target(sc->device));
1691	session = cls_session->dd_data;
1692	spin_lock_bh(&session->frwd_lock);
1693
1694	reason = iscsi_session_chkready(cls_session);
1695	if (reason) {
1696		sc->result = reason;
1697		goto fault;
1698	}
1699
1700	if (session->state != ISCSI_STATE_LOGGED_IN) {
1701		/*
1702		 * to handle the race between when we set the recovery state
1703		 * and block the session we requeue here (commands could
1704		 * be entering our queuecommand while a block is starting
1705		 * up because the block code is not locked)
1706		 */
1707		switch (session->state) {
1708		case ISCSI_STATE_FAILED:
1709			/*
1710			 * cmds should fail during shutdown, if the session
1711			 * state is bad, allowing completion to happen
1712			 */
1713			if (unlikely(system_state != SYSTEM_RUNNING)) {
1714				reason = FAILURE_SESSION_FAILED;
1715				sc->result = DID_NO_CONNECT << 16;
1716				break;
1717			}
1718			fallthrough;
1719		case ISCSI_STATE_IN_RECOVERY:
1720			reason = FAILURE_SESSION_IN_RECOVERY;
1721			sc->result = DID_IMM_RETRY << 16;
1722			break;
1723		case ISCSI_STATE_LOGGING_OUT:
1724			reason = FAILURE_SESSION_LOGGING_OUT;
1725			sc->result = DID_IMM_RETRY << 16;
1726			break;
1727		case ISCSI_STATE_RECOVERY_FAILED:
1728			reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1729			sc->result = DID_TRANSPORT_FAILFAST << 16;
1730			break;
1731		case ISCSI_STATE_TERMINATE:
1732			reason = FAILURE_SESSION_TERMINATE;
1733			sc->result = DID_NO_CONNECT << 16;
1734			break;
1735		default:
1736			reason = FAILURE_SESSION_FREED;
1737			sc->result = DID_NO_CONNECT << 16;
1738		}
1739		goto fault;
1740	}
1741
1742	conn = session->leadconn;
1743	if (!conn) {
1744		reason = FAILURE_SESSION_FREED;
1745		sc->result = DID_NO_CONNECT << 16;
1746		goto fault;
1747	}
1748
1749	if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1750		reason = FAILURE_SESSION_IN_RECOVERY;
1751		sc->result = DID_REQUEUE << 16;
1752		goto fault;
1753	}
1754
1755	if (iscsi_check_cmdsn_window_closed(conn)) {
1756		reason = FAILURE_WINDOW_CLOSED;
1757		goto reject;
1758	}
1759
1760	task = iscsi_alloc_task(conn, sc);
1761	if (!task) {
1762		reason = FAILURE_OOM;
1763		goto reject;
1764	}
1765
1766	if (!ihost->workq) {
1767		reason = iscsi_prep_scsi_cmd_pdu(task);
1768		if (reason) {
1769			if (reason == -ENOMEM ||  reason == -EACCES) {
1770				reason = FAILURE_OOM;
1771				goto prepd_reject;
1772			} else {
1773				sc->result = DID_ABORT << 16;
1774				goto prepd_fault;
1775			}
1776		}
1777		if (session->tt->xmit_task(task)) {
1778			session->cmdsn--;
1779			reason = FAILURE_SESSION_NOT_READY;
1780			goto prepd_reject;
1781		}
1782	} else {
1783		list_add_tail(&task->running, &conn->cmdqueue);
1784		iscsi_conn_queue_work(conn);
1785	}
1786
1787	session->queued_cmdsn++;
1788	spin_unlock_bh(&session->frwd_lock);
1789	return 0;
1790
1791prepd_reject:
1792	spin_lock_bh(&session->back_lock);
1793	iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1794	spin_unlock_bh(&session->back_lock);
1795reject:
1796	spin_unlock_bh(&session->frwd_lock);
1797	ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
1798			  sc->cmnd[0], reason);
1799	return SCSI_MLQUEUE_TARGET_BUSY;
1800
1801prepd_fault:
1802	spin_lock_bh(&session->back_lock);
1803	iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1804	spin_unlock_bh(&session->back_lock);
1805fault:
1806	spin_unlock_bh(&session->frwd_lock);
1807	ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
1808			  sc->cmnd[0], reason);
1809	scsi_set_resid(sc, scsi_bufflen(sc));
 
 
 
 
 
1810	sc->scsi_done(sc);
1811	return 0;
1812}
1813EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1814
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1815int iscsi_target_alloc(struct scsi_target *starget)
1816{
1817	struct iscsi_cls_session *cls_session = starget_to_session(starget);
1818	struct iscsi_session *session = cls_session->dd_data;
1819
1820	starget->can_queue = session->scsi_cmds_max;
1821	return 0;
1822}
1823EXPORT_SYMBOL_GPL(iscsi_target_alloc);
1824
1825static void iscsi_tmf_timedout(struct timer_list *t)
1826{
1827	struct iscsi_session *session = from_timer(session, t, tmf_timer);
 
1828
1829	spin_lock(&session->frwd_lock);
1830	if (session->tmf_state == TMF_QUEUED) {
1831		session->tmf_state = TMF_TIMEDOUT;
1832		ISCSI_DBG_EH(session, "tmf timedout\n");
1833		/* unblock eh_abort() */
1834		wake_up(&session->ehwait);
1835	}
1836	spin_unlock(&session->frwd_lock);
1837}
1838
1839static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1840				   struct iscsi_tm *hdr, int age,
1841				   int timeout)
1842	__must_hold(&session->frwd_lock)
1843{
1844	struct iscsi_session *session = conn->session;
1845	struct iscsi_task *task;
1846
1847	task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1848				      NULL, 0);
1849	if (!task) {
1850		spin_unlock_bh(&session->frwd_lock);
1851		iscsi_conn_printk(KERN_ERR, conn, "Could not send TMF.\n");
1852		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1853		spin_lock_bh(&session->frwd_lock);
1854		return -EPERM;
1855	}
1856	conn->tmfcmd_pdus_cnt++;
1857	session->tmf_timer.expires = timeout * HZ + jiffies;
1858	add_timer(&session->tmf_timer);
 
 
1859	ISCSI_DBG_EH(session, "tmf set timeout\n");
1860
1861	spin_unlock_bh(&session->frwd_lock);
1862	mutex_unlock(&session->eh_mutex);
1863
1864	/*
1865	 * block eh thread until:
1866	 *
1867	 * 1) tmf response
1868	 * 2) tmf timeout
1869	 * 3) session is terminated or restarted or userspace has
1870	 * given up on recovery
1871	 */
1872	wait_event_interruptible(session->ehwait, age != session->age ||
1873				 session->state != ISCSI_STATE_LOGGED_IN ||
1874				 session->tmf_state != TMF_QUEUED);
1875	if (signal_pending(current))
1876		flush_signals(current);
1877	del_timer_sync(&session->tmf_timer);
1878
1879	mutex_lock(&session->eh_mutex);
1880	spin_lock_bh(&session->frwd_lock);
1881	/* if the session drops it will clean up the task */
1882	if (age != session->age ||
1883	    session->state != ISCSI_STATE_LOGGED_IN)
1884		return -ENOTCONN;
1885	return 0;
1886}
1887
1888/*
1889 * Fail commands. session frwd lock held and xmit thread flushed.
 
1890 */
1891static void fail_scsi_tasks(struct iscsi_conn *conn, u64 lun, int error)
 
1892{
1893	struct iscsi_session *session = conn->session;
1894	struct iscsi_task *task;
1895	int i;
1896
1897	spin_lock_bh(&session->back_lock);
1898	for (i = 0; i < session->cmds_max; i++) {
1899		task = session->cmds[i];
1900		if (!task->sc || task->state == ISCSI_TASK_FREE)
1901			continue;
1902
1903		if (lun != -1 && lun != task->sc->device->lun)
1904			continue;
1905
1906		__iscsi_get_task(task);
1907		spin_unlock_bh(&session->back_lock);
1908
1909		ISCSI_DBG_SESSION(session,
1910				  "failing sc %p itt 0x%x state %d\n",
1911				  task->sc, task->itt, task->state);
1912		fail_scsi_task(task, error);
1913
1914		spin_unlock_bh(&session->frwd_lock);
1915		iscsi_put_task(task);
1916		spin_lock_bh(&session->frwd_lock);
1917
1918		spin_lock_bh(&session->back_lock);
1919	}
1920
1921	spin_unlock_bh(&session->back_lock);
1922}
1923
1924/**
1925 * iscsi_suspend_queue - suspend iscsi_queuecommand
1926 * @conn: iscsi conn to stop queueing IO on
1927 *
1928 * This grabs the session frwd_lock to make sure no one is in
1929 * xmit_task/queuecommand, and then sets suspend to prevent
1930 * new commands from being queued. This only needs to be called
1931 * by offload drivers that need to sync a path like ep disconnect
1932 * with the iscsi_queuecommand/xmit_task. To start IO again libiscsi
1933 * will call iscsi_start_tx and iscsi_unblock_session when in FFP.
1934 */
1935void iscsi_suspend_queue(struct iscsi_conn *conn)
1936{
1937	spin_lock_bh(&conn->session->frwd_lock);
1938	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1939	spin_unlock_bh(&conn->session->frwd_lock);
1940}
1941EXPORT_SYMBOL_GPL(iscsi_suspend_queue);
1942
1943/**
1944 * iscsi_suspend_tx - suspend iscsi_data_xmit
1945 * @conn: iscsi conn tp stop processing IO on.
1946 *
1947 * This function sets the suspend bit to prevent iscsi_data_xmit
1948 * from sending new IO, and if work is queued on the xmit thread
1949 * it will wait for it to be completed.
1950 */
1951void iscsi_suspend_tx(struct iscsi_conn *conn)
1952{
1953	struct Scsi_Host *shost = conn->session->host;
1954	struct iscsi_host *ihost = shost_priv(shost);
1955
1956	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1957	if (ihost->workq)
1958		flush_workqueue(ihost->workq);
1959}
1960EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
1961
1962static void iscsi_start_tx(struct iscsi_conn *conn)
1963{
1964	clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1965	iscsi_conn_queue_work(conn);
1966}
1967
1968/*
1969 * We want to make sure a ping is in flight. It has timed out.
1970 * And we are not busy processing a pdu that is making
1971 * progress but got started before the ping and is taking a while
1972 * to complete so the ping is just stuck behind it in a queue.
1973 */
1974static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
1975{
1976	if (READ_ONCE(conn->ping_task) &&
1977	    time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1978			   (conn->ping_timeout * HZ), jiffies))
1979		return 1;
1980	else
1981		return 0;
1982}
1983
1984enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
1985{
1986	enum blk_eh_timer_return rc = BLK_EH_DONE;
1987	struct iscsi_task *task = NULL, *running_task;
1988	struct iscsi_cls_session *cls_session;
1989	struct iscsi_session *session;
1990	struct iscsi_conn *conn;
1991	int i;
1992
1993	cls_session = starget_to_session(scsi_target(sc->device));
1994	session = cls_session->dd_data;
1995
1996	ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc);
1997
1998	spin_lock_bh(&session->frwd_lock);
1999	spin_lock(&session->back_lock);
2000	task = (struct iscsi_task *)sc->SCp.ptr;
2001	if (!task) {
2002		/*
2003		 * Raced with completion. Blk layer has taken ownership
2004		 * so let timeout code complete it now.
2005		 */
2006		rc = BLK_EH_DONE;
2007		spin_unlock(&session->back_lock);
2008		goto done;
2009	}
2010	__iscsi_get_task(task);
2011	spin_unlock(&session->back_lock);
2012
2013	if (session->state != ISCSI_STATE_LOGGED_IN) {
2014		/*
2015		 * During shutdown, if session is prematurely disconnected,
2016		 * recovery won't happen and there will be hung cmds. Not
2017		 * handling cmds would trigger EH, also bad in this case.
2018		 * Instead, handle cmd, allow completion to happen and let
2019		 * upper layer to deal with the result.
2020		 */
2021		if (unlikely(system_state != SYSTEM_RUNNING)) {
2022			sc->result = DID_NO_CONNECT << 16;
2023			ISCSI_DBG_EH(session, "sc on shutdown, handled\n");
2024			rc = BLK_EH_DONE;
2025			goto done;
2026		}
2027		/*
2028		 * We are probably in the middle of iscsi recovery so let
2029		 * that complete and handle the error.
2030		 */
2031		rc = BLK_EH_RESET_TIMER;
2032		goto done;
2033	}
2034
2035	conn = session->leadconn;
2036	if (!conn) {
2037		/* In the middle of shuting down */
2038		rc = BLK_EH_RESET_TIMER;
2039		goto done;
2040	}
2041
 
 
 
 
 
 
 
 
 
 
2042	/*
2043	 * If we have sent (at least queued to the network layer) a pdu or
2044	 * recvd one for the task since the last timeout ask for
2045	 * more time. If on the next timeout we have not made progress
2046	 * we can check if it is the task or connection when we send the
2047	 * nop as a ping.
2048	 */
2049	if (time_after(task->last_xfer, task->last_timeout)) {
2050		ISCSI_DBG_EH(session, "Command making progress. Asking "
2051			     "scsi-ml for more time to complete. "
2052			     "Last data xfer at %lu. Last timeout was at "
2053			     "%lu\n.", task->last_xfer, task->last_timeout);
2054		task->have_checked_conn = false;
2055		rc = BLK_EH_RESET_TIMER;
2056		goto done;
2057	}
2058
2059	if (!conn->recv_timeout && !conn->ping_timeout)
2060		goto done;
2061	/*
2062	 * if the ping timedout then we are in the middle of cleaning up
2063	 * and can let the iscsi eh handle it
2064	 */
2065	if (iscsi_has_ping_timed_out(conn)) {
2066		rc = BLK_EH_RESET_TIMER;
2067		goto done;
2068	}
2069
2070	spin_lock(&session->back_lock);
2071	for (i = 0; i < conn->session->cmds_max; i++) {
2072		running_task = conn->session->cmds[i];
2073		if (!running_task->sc || running_task == task ||
2074		     running_task->state != ISCSI_TASK_RUNNING)
2075			continue;
2076
2077		/*
2078		 * Only check if cmds started before this one have made
2079		 * progress, or this could never fail
2080		 */
2081		if (time_after(running_task->sc->jiffies_at_alloc,
2082			       task->sc->jiffies_at_alloc))
2083			continue;
2084
2085		if (time_after(running_task->last_xfer, task->last_timeout)) {
2086			/*
2087			 * This task has not made progress, but a task
2088			 * started before us has transferred data since
2089			 * we started/last-checked. We could be queueing
2090			 * too many tasks or the LU is bad.
2091			 *
2092			 * If the device is bad the cmds ahead of us on
2093			 * other devs will complete, and this loop will
2094			 * eventually fail starting the scsi eh.
2095			 */
2096			ISCSI_DBG_EH(session, "Command has not made progress "
2097				     "but commands ahead of it have. "
2098				     "Asking scsi-ml for more time to "
2099				     "complete. Our last xfer vs running task "
2100				     "last xfer %lu/%lu. Last check %lu.\n",
2101				     task->last_xfer, running_task->last_xfer,
2102				     task->last_timeout);
2103			spin_unlock(&session->back_lock);
2104			rc = BLK_EH_RESET_TIMER;
2105			goto done;
2106		}
2107	}
2108	spin_unlock(&session->back_lock);
2109
2110	/* Assumes nop timeout is shorter than scsi cmd timeout */
2111	if (task->have_checked_conn)
2112		goto done;
2113
2114	/*
2115	 * Checking the transport already or nop from a cmd timeout still
2116	 * running
2117	 */
2118	if (READ_ONCE(conn->ping_task)) {
2119		task->have_checked_conn = true;
2120		rc = BLK_EH_RESET_TIMER;
2121		goto done;
2122	}
2123
2124	/* Make sure there is a transport check done */
2125	iscsi_send_nopout(conn, NULL);
2126	task->have_checked_conn = true;
2127	rc = BLK_EH_RESET_TIMER;
2128
2129done:
2130	spin_unlock_bh(&session->frwd_lock);
2131
2132	if (task) {
2133		task->last_timeout = jiffies;
2134		iscsi_put_task(task);
2135	}
2136	ISCSI_DBG_EH(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
2137		     "timer reset" : "shutdown or nh");
2138	return rc;
2139}
2140EXPORT_SYMBOL_GPL(iscsi_eh_cmd_timed_out);
2141
2142static void iscsi_check_transport_timeouts(struct timer_list *t)
2143{
2144	struct iscsi_conn *conn = from_timer(conn, t, transport_timer);
2145	struct iscsi_session *session = conn->session;
2146	unsigned long recv_timeout, next_timeout = 0, last_recv;
2147
2148	spin_lock(&session->frwd_lock);
2149	if (session->state != ISCSI_STATE_LOGGED_IN)
2150		goto done;
2151
2152	recv_timeout = conn->recv_timeout;
2153	if (!recv_timeout)
2154		goto done;
2155
2156	recv_timeout *= HZ;
2157	last_recv = conn->last_recv;
2158
2159	if (iscsi_has_ping_timed_out(conn)) {
2160		iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
2161				  "expired, recv timeout %d, last rx %lu, "
2162				  "last ping %lu, now %lu\n",
2163				  conn->ping_timeout, conn->recv_timeout,
2164				  last_recv, conn->last_ping, jiffies);
2165		spin_unlock(&session->frwd_lock);
2166		iscsi_conn_failure(conn, ISCSI_ERR_NOP_TIMEDOUT);
2167		return;
2168	}
2169
2170	if (time_before_eq(last_recv + recv_timeout, jiffies)) {
2171		/* send a ping to try to provoke some traffic */
2172		ISCSI_DBG_CONN(conn, "Sending nopout as ping\n");
2173		if (iscsi_send_nopout(conn, NULL))
2174			next_timeout = jiffies + (1 * HZ);
2175		else
2176			next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
2177	} else
2178		next_timeout = last_recv + recv_timeout;
2179
2180	ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout);
2181	mod_timer(&conn->transport_timer, next_timeout);
2182done:
2183	spin_unlock(&session->frwd_lock);
2184}
2185
2186/**
2187 * iscsi_conn_unbind - prevent queueing to conn.
2188 * @cls_conn: iscsi conn ep is bound to.
2189 * @is_active: is the conn in use for boot or is this for EH/termination
2190 *
2191 * This must be called by drivers implementing the ep_disconnect callout.
2192 * It disables queueing to the connection from libiscsi in preparation for
2193 * an ep_disconnect call.
2194 */
2195void iscsi_conn_unbind(struct iscsi_cls_conn *cls_conn, bool is_active)
2196{
2197	struct iscsi_session *session;
2198	struct iscsi_conn *conn;
2199
2200	if (!cls_conn)
2201		return;
2202
2203	conn = cls_conn->dd_data;
2204	session = conn->session;
2205	/*
2206	 * Wait for iscsi_eh calls to exit. We don't wait for the tmf to
2207	 * complete or timeout. The caller just wants to know what's running
2208	 * is everything that needs to be cleaned up, and no cmds will be
2209	 * queued.
2210	 */
2211	mutex_lock(&session->eh_mutex);
2212
2213	iscsi_suspend_queue(conn);
2214	iscsi_suspend_tx(conn);
2215
2216	spin_lock_bh(&session->frwd_lock);
2217	if (!is_active) {
2218		/*
2219		 * if logout timed out before userspace could even send a PDU
2220		 * the state might still be in ISCSI_STATE_LOGGED_IN and
2221		 * allowing new cmds and TMFs.
2222		 */
2223		if (session->state == ISCSI_STATE_LOGGED_IN)
2224			iscsi_set_conn_failed(conn);
2225	}
2226	spin_unlock_bh(&session->frwd_lock);
2227	mutex_unlock(&session->eh_mutex);
2228}
2229EXPORT_SYMBOL_GPL(iscsi_conn_unbind);
2230
2231static void iscsi_prep_abort_task_pdu(struct iscsi_task *task,
2232				      struct iscsi_tm *hdr)
2233{
2234	memset(hdr, 0, sizeof(*hdr));
2235	hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2236	hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
2237	hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2238	hdr->lun = task->lun;
2239	hdr->rtt = task->hdr_itt;
2240	hdr->refcmdsn = task->cmdsn;
2241}
2242
2243int iscsi_eh_abort(struct scsi_cmnd *sc)
2244{
2245	struct iscsi_cls_session *cls_session;
2246	struct iscsi_session *session;
2247	struct iscsi_conn *conn;
2248	struct iscsi_task *task;
2249	struct iscsi_tm *hdr;
2250	int age;
2251
2252	cls_session = starget_to_session(scsi_target(sc->device));
2253	session = cls_session->dd_data;
2254
2255	ISCSI_DBG_EH(session, "aborting sc %p\n", sc);
2256
2257	mutex_lock(&session->eh_mutex);
2258	spin_lock_bh(&session->frwd_lock);
2259	/*
2260	 * if session was ISCSI_STATE_IN_RECOVERY then we may not have
2261	 * got the command.
2262	 */
2263	if (!sc->SCp.ptr) {
2264		ISCSI_DBG_EH(session, "sc never reached iscsi layer or "
2265				      "it completed.\n");
2266		spin_unlock_bh(&session->frwd_lock);
2267		mutex_unlock(&session->eh_mutex);
2268		return SUCCESS;
2269	}
2270
2271	/*
2272	 * If we are not logged in or we have started a new session
2273	 * then let the host reset code handle this
2274	 */
2275	if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
2276	    sc->SCp.phase != session->age) {
2277		spin_unlock_bh(&session->frwd_lock);
2278		mutex_unlock(&session->eh_mutex);
2279		ISCSI_DBG_EH(session, "failing abort due to dropped "
2280				  "session.\n");
2281		return FAILED;
2282	}
2283
2284	spin_lock(&session->back_lock);
2285	task = (struct iscsi_task *)sc->SCp.ptr;
2286	if (!task || !task->sc) {
2287		/* task completed before time out */
2288		ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
2289
2290		spin_unlock(&session->back_lock);
2291		spin_unlock_bh(&session->frwd_lock);
2292		mutex_unlock(&session->eh_mutex);
2293		return SUCCESS;
2294	}
2295
2296	conn = session->leadconn;
2297	iscsi_get_conn(conn->cls_conn);
2298	conn->eh_abort_cnt++;
2299	age = session->age;
2300
2301	ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n", sc, task->itt);
2302	__iscsi_get_task(task);
2303	spin_unlock(&session->back_lock);
 
 
 
 
 
 
2304
2305	if (task->state == ISCSI_TASK_PENDING) {
2306		fail_scsi_task(task, DID_ABORT);
2307		goto success;
2308	}
2309
2310	/* only have one tmf outstanding at a time */
2311	if (session->tmf_state != TMF_INITIAL)
2312		goto failed;
2313	session->tmf_state = TMF_QUEUED;
2314
2315	hdr = &session->tmhdr;
2316	iscsi_prep_abort_task_pdu(task, hdr);
2317
2318	if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout))
 
2319		goto failed;
 
2320
2321	switch (session->tmf_state) {
2322	case TMF_SUCCESS:
2323		spin_unlock_bh(&session->frwd_lock);
2324		/*
2325		 * stop tx side incase the target had sent a abort rsp but
2326		 * the initiator was still writing out data.
2327		 */
2328		iscsi_suspend_tx(conn);
2329		/*
2330		 * we do not stop the recv side because targets have been
2331		 * good and have never sent us a successful tmf response
2332		 * then sent more data for the cmd.
2333		 */
2334		spin_lock_bh(&session->frwd_lock);
2335		fail_scsi_task(task, DID_ABORT);
2336		session->tmf_state = TMF_INITIAL;
2337		memset(hdr, 0, sizeof(*hdr));
2338		spin_unlock_bh(&session->frwd_lock);
2339		iscsi_start_tx(conn);
2340		goto success_unlocked;
2341	case TMF_TIMEDOUT:
2342		session->running_aborted_task = task;
2343		spin_unlock_bh(&session->frwd_lock);
2344		iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2345		goto failed_unlocked;
2346	case TMF_NOT_FOUND:
2347		if (iscsi_task_is_completed(task)) {
2348			session->tmf_state = TMF_INITIAL;
2349			memset(hdr, 0, sizeof(*hdr));
2350			/* task completed before tmf abort response */
2351			ISCSI_DBG_EH(session, "sc completed while abort	in "
2352					      "progress\n");
2353			goto success;
2354		}
2355		fallthrough;
2356	default:
2357		session->tmf_state = TMF_INITIAL;
2358		goto failed;
2359	}
2360
2361success:
2362	spin_unlock_bh(&session->frwd_lock);
2363success_unlocked:
2364	ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n",
2365		     sc, task->itt);
2366	iscsi_put_task(task);
2367	iscsi_put_conn(conn->cls_conn);
2368	mutex_unlock(&session->eh_mutex);
2369	return SUCCESS;
2370
2371failed:
2372	spin_unlock_bh(&session->frwd_lock);
2373failed_unlocked:
2374	ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
2375		     task ? task->itt : 0);
2376	/*
2377	 * The driver might be accessing the task so hold the ref. The conn
2378	 * stop cleanup will drop the ref after ep_disconnect so we know the
2379	 * driver's no longer touching the task.
2380	 */
2381	if (!session->running_aborted_task)
2382		iscsi_put_task(task);
2383
2384	iscsi_put_conn(conn->cls_conn);
2385	mutex_unlock(&session->eh_mutex);
2386	return FAILED;
2387}
2388EXPORT_SYMBOL_GPL(iscsi_eh_abort);
2389
2390static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2391{
2392	memset(hdr, 0, sizeof(*hdr));
2393	hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2394	hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2395	hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2396	int_to_scsilun(sc->device->lun, &hdr->lun);
2397	hdr->rtt = RESERVED_ITT;
2398}
2399
2400int iscsi_eh_device_reset(struct scsi_cmnd *sc)
2401{
2402	struct iscsi_cls_session *cls_session;
2403	struct iscsi_session *session;
2404	struct iscsi_conn *conn;
2405	struct iscsi_tm *hdr;
2406	int rc = FAILED;
2407
2408	cls_session = starget_to_session(scsi_target(sc->device));
2409	session = cls_session->dd_data;
2410
2411	ISCSI_DBG_EH(session, "LU Reset [sc %p lun %llu]\n", sc,
2412		     sc->device->lun);
2413
2414	mutex_lock(&session->eh_mutex);
2415	spin_lock_bh(&session->frwd_lock);
2416	/*
2417	 * Just check if we are not logged in. We cannot check for
2418	 * the phase because the reset could come from a ioctl.
2419	 */
2420	if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2421		goto unlock;
2422	conn = session->leadconn;
2423
2424	/* only have one tmf outstanding at a time */
2425	if (session->tmf_state != TMF_INITIAL)
2426		goto unlock;
2427	session->tmf_state = TMF_QUEUED;
2428
2429	hdr = &session->tmhdr;
2430	iscsi_prep_lun_reset_pdu(sc, hdr);
2431
2432	if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2433				    session->lu_reset_timeout)) {
2434		rc = FAILED;
2435		goto unlock;
2436	}
2437
2438	switch (session->tmf_state) {
2439	case TMF_SUCCESS:
2440		break;
2441	case TMF_TIMEDOUT:
2442		spin_unlock_bh(&session->frwd_lock);
2443		iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2444		goto done;
2445	default:
2446		session->tmf_state = TMF_INITIAL;
2447		goto unlock;
2448	}
2449
2450	rc = SUCCESS;
2451	spin_unlock_bh(&session->frwd_lock);
2452
2453	iscsi_suspend_tx(conn);
2454
2455	spin_lock_bh(&session->frwd_lock);
2456	memset(hdr, 0, sizeof(*hdr));
2457	fail_scsi_tasks(conn, sc->device->lun, DID_ERROR);
2458	session->tmf_state = TMF_INITIAL;
2459	spin_unlock_bh(&session->frwd_lock);
2460
2461	iscsi_start_tx(conn);
2462	goto done;
2463
2464unlock:
2465	spin_unlock_bh(&session->frwd_lock);
2466done:
2467	ISCSI_DBG_EH(session, "dev reset result = %s\n",
2468		     rc == SUCCESS ? "SUCCESS" : "FAILED");
2469	mutex_unlock(&session->eh_mutex);
2470	return rc;
2471}
2472EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
2473
2474void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
2475{
2476	struct iscsi_session *session = cls_session->dd_data;
2477
2478	spin_lock_bh(&session->frwd_lock);
2479	if (session->state != ISCSI_STATE_LOGGED_IN) {
2480		session->state = ISCSI_STATE_RECOVERY_FAILED;
2481		wake_up(&session->ehwait);
 
2482	}
2483	spin_unlock_bh(&session->frwd_lock);
2484}
2485EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
2486
2487/**
2488 * iscsi_eh_session_reset - drop session and attempt relogin
2489 * @sc: scsi command
2490 *
2491 * This function will wait for a relogin, session termination from
2492 * userspace, or a recovery/replacement timeout.
2493 */
2494int iscsi_eh_session_reset(struct scsi_cmnd *sc)
2495{
2496	struct iscsi_cls_session *cls_session;
2497	struct iscsi_session *session;
2498	struct iscsi_conn *conn;
2499
2500	cls_session = starget_to_session(scsi_target(sc->device));
2501	session = cls_session->dd_data;
 
2502
2503	mutex_lock(&session->eh_mutex);
2504	spin_lock_bh(&session->frwd_lock);
2505	if (session->state == ISCSI_STATE_TERMINATE) {
2506failed:
2507		ISCSI_DBG_EH(session,
2508			     "failing session reset: Could not log back into "
2509			     "%s [age %d]\n", session->targetname,
2510			     session->age);
2511		spin_unlock_bh(&session->frwd_lock);
2512		mutex_unlock(&session->eh_mutex);
2513		return FAILED;
2514	}
2515
2516	conn = session->leadconn;
2517	iscsi_get_conn(conn->cls_conn);
2518
2519	spin_unlock_bh(&session->frwd_lock);
2520	mutex_unlock(&session->eh_mutex);
2521
 
 
 
2522	iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2523	iscsi_put_conn(conn->cls_conn);
2524
2525	ISCSI_DBG_EH(session, "wait for relogin\n");
2526	wait_event_interruptible(session->ehwait,
2527				 session->state == ISCSI_STATE_TERMINATE ||
2528				 session->state == ISCSI_STATE_LOGGED_IN ||
2529				 session->state == ISCSI_STATE_RECOVERY_FAILED);
2530	if (signal_pending(current))
2531		flush_signals(current);
2532
2533	mutex_lock(&session->eh_mutex);
2534	spin_lock_bh(&session->frwd_lock);
2535	if (session->state == ISCSI_STATE_LOGGED_IN) {
2536		ISCSI_DBG_EH(session,
2537			     "session reset succeeded for %s,%s\n",
2538			     session->targetname, conn->persistent_address);
2539	} else
2540		goto failed;
2541	spin_unlock_bh(&session->frwd_lock);
2542	mutex_unlock(&session->eh_mutex);
2543	return SUCCESS;
2544}
2545EXPORT_SYMBOL_GPL(iscsi_eh_session_reset);
2546
2547static void iscsi_prep_tgt_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2548{
2549	memset(hdr, 0, sizeof(*hdr));
2550	hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2551	hdr->flags = ISCSI_TM_FUNC_TARGET_WARM_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2552	hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2553	hdr->rtt = RESERVED_ITT;
2554}
2555
2556/**
2557 * iscsi_eh_target_reset - reset target
2558 * @sc: scsi command
2559 *
2560 * This will attempt to send a warm target reset.
2561 */
2562static int iscsi_eh_target_reset(struct scsi_cmnd *sc)
2563{
2564	struct iscsi_cls_session *cls_session;
2565	struct iscsi_session *session;
2566	struct iscsi_conn *conn;
2567	struct iscsi_tm *hdr;
2568	int rc = FAILED;
2569
2570	cls_session = starget_to_session(scsi_target(sc->device));
2571	session = cls_session->dd_data;
2572
2573	ISCSI_DBG_EH(session, "tgt Reset [sc %p tgt %s]\n", sc,
2574		     session->targetname);
2575
2576	mutex_lock(&session->eh_mutex);
2577	spin_lock_bh(&session->frwd_lock);
2578	/*
2579	 * Just check if we are not logged in. We cannot check for
2580	 * the phase because the reset could come from a ioctl.
2581	 */
2582	if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2583		goto unlock;
2584	conn = session->leadconn;
2585
2586	/* only have one tmf outstanding at a time */
2587	if (session->tmf_state != TMF_INITIAL)
2588		goto unlock;
2589	session->tmf_state = TMF_QUEUED;
2590
2591	hdr = &session->tmhdr;
2592	iscsi_prep_tgt_reset_pdu(sc, hdr);
2593
2594	if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2595				    session->tgt_reset_timeout)) {
2596		rc = FAILED;
2597		goto unlock;
2598	}
2599
2600	switch (session->tmf_state) {
2601	case TMF_SUCCESS:
2602		break;
2603	case TMF_TIMEDOUT:
2604		spin_unlock_bh(&session->frwd_lock);
2605		iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2606		goto done;
2607	default:
2608		session->tmf_state = TMF_INITIAL;
2609		goto unlock;
2610	}
2611
2612	rc = SUCCESS;
2613	spin_unlock_bh(&session->frwd_lock);
2614
2615	iscsi_suspend_tx(conn);
2616
2617	spin_lock_bh(&session->frwd_lock);
2618	memset(hdr, 0, sizeof(*hdr));
2619	fail_scsi_tasks(conn, -1, DID_ERROR);
2620	session->tmf_state = TMF_INITIAL;
2621	spin_unlock_bh(&session->frwd_lock);
2622
2623	iscsi_start_tx(conn);
2624	goto done;
2625
2626unlock:
2627	spin_unlock_bh(&session->frwd_lock);
2628done:
2629	ISCSI_DBG_EH(session, "tgt %s reset result = %s\n", session->targetname,
2630		     rc == SUCCESS ? "SUCCESS" : "FAILED");
2631	mutex_unlock(&session->eh_mutex);
2632	return rc;
2633}
 
2634
2635/**
2636 * iscsi_eh_recover_target - reset target and possibly the session
2637 * @sc: scsi command
2638 *
2639 * This will attempt to send a warm target reset. If that fails,
2640 * we will escalate to ERL0 session recovery.
2641 */
2642int iscsi_eh_recover_target(struct scsi_cmnd *sc)
2643{
2644	int rc;
2645
2646	rc = iscsi_eh_target_reset(sc);
2647	if (rc == FAILED)
2648		rc = iscsi_eh_session_reset(sc);
2649	return rc;
2650}
2651EXPORT_SYMBOL_GPL(iscsi_eh_recover_target);
2652
2653/*
2654 * Pre-allocate a pool of @max items of @item_size. By default, the pool
2655 * should be accessed via kfifo_{get,put} on q->queue.
2656 * Optionally, the caller can obtain the array of object pointers
2657 * by passing in a non-NULL @items pointer
2658 */
2659int
2660iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
2661{
2662	int i, num_arrays = 1;
2663
2664	memset(q, 0, sizeof(*q));
2665
2666	q->max = max;
2667
2668	/* If the user passed an items pointer, he wants a copy of
2669	 * the array. */
2670	if (items)
2671		num_arrays++;
2672	q->pool = kvcalloc(num_arrays * max, sizeof(void *), GFP_KERNEL);
2673	if (q->pool == NULL)
2674		return -ENOMEM;
2675
2676	kfifo_init(&q->queue, (void*)q->pool, max * sizeof(void*));
2677
2678	for (i = 0; i < max; i++) {
2679		q->pool[i] = kzalloc(item_size, GFP_KERNEL);
2680		if (q->pool[i] == NULL) {
2681			q->max = i;
2682			goto enomem;
2683		}
2684		kfifo_in(&q->queue, (void*)&q->pool[i], sizeof(void*));
2685	}
2686
2687	if (items) {
2688		*items = q->pool + max;
2689		memcpy(*items, q->pool, max * sizeof(void *));
2690	}
2691
2692	return 0;
2693
2694enomem:
2695	iscsi_pool_free(q);
2696	return -ENOMEM;
2697}
2698EXPORT_SYMBOL_GPL(iscsi_pool_init);
2699
2700void iscsi_pool_free(struct iscsi_pool *q)
2701{
2702	int i;
2703
2704	for (i = 0; i < q->max; i++)
2705		kfree(q->pool[i]);
2706	kvfree(q->pool);
2707}
2708EXPORT_SYMBOL_GPL(iscsi_pool_free);
2709
2710int iscsi_host_get_max_scsi_cmds(struct Scsi_Host *shost,
2711				 uint16_t requested_cmds_max)
2712{
2713	int scsi_cmds, total_cmds = requested_cmds_max;
2714
2715check:
2716	if (!total_cmds)
2717		total_cmds = ISCSI_DEF_XMIT_CMDS_MAX;
2718	/*
2719	 * The iscsi layer needs some tasks for nop handling and tmfs,
2720	 * so the cmds_max must at least be greater than ISCSI_MGMT_CMDS_MAX
2721	 * + 1 command for scsi IO.
2722	 */
2723	if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
2724		printk(KERN_ERR "iscsi: invalid max cmds of %d. Must be a power of two that is at least %d.\n",
2725		       total_cmds, ISCSI_TOTAL_CMDS_MIN);
2726		return -EINVAL;
2727	}
2728
2729	if (total_cmds > ISCSI_TOTAL_CMDS_MAX) {
2730		printk(KERN_INFO "iscsi: invalid max cmds of %d. Must be a power of 2 less than or equal to %d. Using %d.\n",
2731		       requested_cmds_max, ISCSI_TOTAL_CMDS_MAX,
2732		       ISCSI_TOTAL_CMDS_MAX);
2733		total_cmds = ISCSI_TOTAL_CMDS_MAX;
2734	}
2735
2736	if (!is_power_of_2(total_cmds)) {
2737		total_cmds = rounddown_pow_of_two(total_cmds);
2738		if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
2739			printk(KERN_ERR "iscsi: invalid max cmds of %d. Must be a power of 2 greater than %d.\n", requested_cmds_max, ISCSI_TOTAL_CMDS_MIN);
2740			return -EINVAL;
2741		}
2742
2743		printk(KERN_INFO "iscsi: invalid max cmds %d. Must be a power of 2. Rounding max cmds down to %d.\n",
2744		       requested_cmds_max, total_cmds);
2745	}
2746
2747	scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX;
2748	if (shost->can_queue && scsi_cmds > shost->can_queue) {
2749		total_cmds = shost->can_queue;
2750
2751		printk(KERN_INFO "iscsi: requested max cmds %u is higher than driver limit. Using driver limit %u\n",
2752		       requested_cmds_max, shost->can_queue);
2753		goto check;
2754	}
2755
2756	return scsi_cmds;
2757}
2758EXPORT_SYMBOL_GPL(iscsi_host_get_max_scsi_cmds);
2759
2760/**
2761 * iscsi_host_add - add host to system
2762 * @shost: scsi host
2763 * @pdev: parent device
2764 *
2765 * This should be called by partial offload and software iscsi drivers
2766 * to add a host to the system.
2767 */
2768int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
2769{
2770	if (!shost->can_queue)
2771		shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX;
2772
2773	if (!shost->cmd_per_lun)
2774		shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN;
2775
 
 
2776	return scsi_add_host(shost, pdev);
2777}
2778EXPORT_SYMBOL_GPL(iscsi_host_add);
2779
2780/**
2781 * iscsi_host_alloc - allocate a host and driver data
2782 * @sht: scsi host template
2783 * @dd_data_size: driver host data size
2784 * @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
2785 *
2786 * This should be called by partial offload and software iscsi drivers.
2787 * To access the driver specific memory use the iscsi_host_priv() macro.
2788 */
2789struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
2790				   int dd_data_size, bool xmit_can_sleep)
2791{
2792	struct Scsi_Host *shost;
2793	struct iscsi_host *ihost;
2794
2795	shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
2796	if (!shost)
2797		return NULL;
2798	ihost = shost_priv(shost);
2799
2800	if (xmit_can_sleep) {
2801		snprintf(ihost->workq_name, sizeof(ihost->workq_name),
2802			"iscsi_q_%d", shost->host_no);
2803		ihost->workq = alloc_workqueue("%s",
2804			WQ_SYSFS | __WQ_LEGACY | WQ_MEM_RECLAIM | WQ_UNBOUND,
2805			1, ihost->workq_name);
2806		if (!ihost->workq)
2807			goto free_host;
2808	}
2809
2810	spin_lock_init(&ihost->lock);
2811	ihost->state = ISCSI_HOST_SETUP;
2812	ihost->num_sessions = 0;
2813	init_waitqueue_head(&ihost->session_removal_wq);
2814	return shost;
2815
2816free_host:
2817	scsi_host_put(shost);
2818	return NULL;
2819}
2820EXPORT_SYMBOL_GPL(iscsi_host_alloc);
2821
2822static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
2823{
2824	iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST);
2825}
2826
2827/**
2828 * iscsi_host_remove - remove host and sessions
2829 * @shost: scsi host
2830 *
2831 * If there are any sessions left, this will initiate the removal and wait
2832 * for the completion.
2833 */
2834void iscsi_host_remove(struct Scsi_Host *shost)
2835{
2836	struct iscsi_host *ihost = shost_priv(shost);
2837	unsigned long flags;
2838
2839	spin_lock_irqsave(&ihost->lock, flags);
2840	ihost->state = ISCSI_HOST_REMOVED;
2841	spin_unlock_irqrestore(&ihost->lock, flags);
2842
2843	iscsi_host_for_each_session(shost, iscsi_notify_host_removed);
2844	wait_event_interruptible(ihost->session_removal_wq,
2845				 ihost->num_sessions == 0);
2846	if (signal_pending(current))
2847		flush_signals(current);
2848
2849	scsi_remove_host(shost);
 
 
2850}
2851EXPORT_SYMBOL_GPL(iscsi_host_remove);
2852
2853void iscsi_host_free(struct Scsi_Host *shost)
2854{
2855	struct iscsi_host *ihost = shost_priv(shost);
2856
2857	if (ihost->workq)
2858		destroy_workqueue(ihost->workq);
2859
2860	kfree(ihost->netdev);
2861	kfree(ihost->hwaddress);
2862	kfree(ihost->initiatorname);
2863	scsi_host_put(shost);
2864}
2865EXPORT_SYMBOL_GPL(iscsi_host_free);
2866
2867static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost)
2868{
2869	struct iscsi_host *ihost = shost_priv(shost);
2870	unsigned long flags;
2871
2872	shost = scsi_host_get(shost);
2873	if (!shost) {
2874		printk(KERN_ERR "Invalid state. Cannot notify host removal "
2875		      "of session teardown event because host already "
2876		      "removed.\n");
2877		return;
2878	}
2879
2880	spin_lock_irqsave(&ihost->lock, flags);
2881	ihost->num_sessions--;
2882	if (ihost->num_sessions == 0)
2883		wake_up(&ihost->session_removal_wq);
2884	spin_unlock_irqrestore(&ihost->lock, flags);
2885	scsi_host_put(shost);
2886}
2887
2888/**
2889 * iscsi_session_setup - create iscsi cls session and host and session
2890 * @iscsit: iscsi transport template
2891 * @shost: scsi host
2892 * @cmds_max: session can queue
2893 * @dd_size: private driver data size, added to session allocation size
2894 * @cmd_task_size: LLD task private data size
2895 * @initial_cmdsn: initial CmdSN
2896 * @id: target ID to add to this session
2897 *
2898 * This can be used by software iscsi_transports that allocate
2899 * a session per scsi host.
2900 *
2901 * Callers should set cmds_max to the largest total numer (mgmt + scsi) of
2902 * tasks they support. The iscsi layer reserves ISCSI_MGMT_CMDS_MAX tasks
2903 * for nop handling and login/logout requests.
2904 */
2905struct iscsi_cls_session *
2906iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
2907		    uint16_t cmds_max, int dd_size, int cmd_task_size,
2908		    uint32_t initial_cmdsn, unsigned int id)
2909{
2910	struct iscsi_host *ihost = shost_priv(shost);
2911	struct iscsi_session *session;
2912	struct iscsi_cls_session *cls_session;
2913	int cmd_i, scsi_cmds;
2914	unsigned long flags;
2915
2916	spin_lock_irqsave(&ihost->lock, flags);
2917	if (ihost->state == ISCSI_HOST_REMOVED) {
2918		spin_unlock_irqrestore(&ihost->lock, flags);
2919		return NULL;
2920	}
2921	ihost->num_sessions++;
2922	spin_unlock_irqrestore(&ihost->lock, flags);
2923
2924	scsi_cmds = iscsi_host_get_max_scsi_cmds(shost, cmds_max);
2925	if (scsi_cmds < 0)
 
 
 
 
 
 
 
 
 
2926		goto dec_session_count;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2927
2928	cls_session = iscsi_alloc_session(shost, iscsit,
2929					  sizeof(struct iscsi_session) +
2930					  dd_size);
2931	if (!cls_session)
2932		goto dec_session_count;
2933	session = cls_session->dd_data;
2934	session->cls_session = cls_session;
2935	session->host = shost;
2936	session->state = ISCSI_STATE_FREE;
2937	session->fast_abort = 1;
2938	session->tgt_reset_timeout = 30;
2939	session->lu_reset_timeout = 15;
2940	session->abort_timeout = 10;
2941	session->scsi_cmds_max = scsi_cmds;
2942	session->cmds_max = scsi_cmds + ISCSI_MGMT_CMDS_MAX;
2943	session->queued_cmdsn = session->cmdsn = initial_cmdsn;
2944	session->exp_cmdsn = initial_cmdsn + 1;
2945	session->max_cmdsn = initial_cmdsn + 1;
2946	session->max_r2t = 1;
2947	session->tt = iscsit;
2948	session->dd_data = cls_session->dd_data + sizeof(*session);
2949
2950	session->tmf_state = TMF_INITIAL;
2951	timer_setup(&session->tmf_timer, iscsi_tmf_timedout, 0);
2952	mutex_init(&session->eh_mutex);
2953
2954	spin_lock_init(&session->frwd_lock);
2955	spin_lock_init(&session->back_lock);
2956
2957	/* initialize SCSI PDU commands pool */
2958	if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
2959			    (void***)&session->cmds,
2960			    cmd_task_size + sizeof(struct iscsi_task)))
2961		goto cmdpool_alloc_fail;
2962
2963	/* pre-format cmds pool with ITT */
2964	for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
2965		struct iscsi_task *task = session->cmds[cmd_i];
2966
2967		if (cmd_task_size)
2968			task->dd_data = &task[1];
2969		task->itt = cmd_i;
2970		task->state = ISCSI_TASK_FREE;
2971		INIT_LIST_HEAD(&task->running);
2972	}
2973
2974	if (!try_module_get(iscsit->owner))
2975		goto module_get_fail;
2976
2977	if (iscsi_add_session(cls_session, id))
2978		goto cls_session_fail;
2979
2980	return cls_session;
2981
2982cls_session_fail:
2983	module_put(iscsit->owner);
2984module_get_fail:
2985	iscsi_pool_free(&session->cmdpool);
2986cmdpool_alloc_fail:
2987	iscsi_free_session(cls_session);
2988dec_session_count:
2989	iscsi_host_dec_session_cnt(shost);
2990	return NULL;
2991}
2992EXPORT_SYMBOL_GPL(iscsi_session_setup);
2993
2994/**
2995 * iscsi_session_teardown - destroy session, host, and cls_session
2996 * @cls_session: iscsi session
 
 
 
2997 */
2998void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
2999{
3000	struct iscsi_session *session = cls_session->dd_data;
3001	struct module *owner = cls_session->transport->owner;
3002	struct Scsi_Host *shost = session->host;
3003
3004	iscsi_remove_session(cls_session);
3005
3006	iscsi_pool_free(&session->cmdpool);
 
3007	kfree(session->password);
3008	kfree(session->password_in);
3009	kfree(session->username);
3010	kfree(session->username_in);
3011	kfree(session->targetname);
3012	kfree(session->targetalias);
3013	kfree(session->initiatorname);
3014	kfree(session->boot_root);
3015	kfree(session->boot_nic);
3016	kfree(session->boot_target);
3017	kfree(session->ifacename);
3018	kfree(session->portal_type);
3019	kfree(session->discovery_parent_type);
3020
3021	iscsi_free_session(cls_session);
3022
 
3023	iscsi_host_dec_session_cnt(shost);
3024	module_put(owner);
3025}
3026EXPORT_SYMBOL_GPL(iscsi_session_teardown);
3027
3028/**
3029 * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
3030 * @cls_session: iscsi_cls_session
3031 * @dd_size: private driver data size
3032 * @conn_idx: cid
3033 */
3034struct iscsi_cls_conn *
3035iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
3036		 uint32_t conn_idx)
3037{
3038	struct iscsi_session *session = cls_session->dd_data;
3039	struct iscsi_conn *conn;
3040	struct iscsi_cls_conn *cls_conn;
3041	char *data;
3042
3043	cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size,
3044				     conn_idx);
3045	if (!cls_conn)
3046		return NULL;
3047	conn = cls_conn->dd_data;
3048	memset(conn, 0, sizeof(*conn) + dd_size);
3049
3050	conn->dd_data = cls_conn->dd_data + sizeof(*conn);
3051	conn->session = session;
3052	conn->cls_conn = cls_conn;
3053	conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
3054	conn->id = conn_idx;
3055	conn->exp_statsn = 0;
 
3056
3057	timer_setup(&conn->transport_timer, iscsi_check_transport_timeouts, 0);
 
 
3058
3059	INIT_LIST_HEAD(&conn->mgmtqueue);
3060	INIT_LIST_HEAD(&conn->cmdqueue);
3061	INIT_LIST_HEAD(&conn->requeue);
3062	INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
3063
3064	/* allocate login_task used for the login/text sequences */
3065	spin_lock_bh(&session->frwd_lock);
3066	if (!kfifo_out(&session->cmdpool.queue,
3067                         (void*)&conn->login_task,
3068			 sizeof(void*))) {
3069		spin_unlock_bh(&session->frwd_lock);
3070		goto login_task_alloc_fail;
3071	}
3072	spin_unlock_bh(&session->frwd_lock);
3073
3074	data = (char *) __get_free_pages(GFP_KERNEL,
3075					 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
3076	if (!data)
3077		goto login_task_data_alloc_fail;
3078	conn->login_task->data = conn->data = data;
3079
3080	init_waitqueue_head(&session->ehwait);
 
3081
3082	return cls_conn;
3083
3084login_task_data_alloc_fail:
3085	kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
3086		    sizeof(void*));
3087login_task_alloc_fail:
3088	iscsi_destroy_conn(cls_conn);
3089	return NULL;
3090}
3091EXPORT_SYMBOL_GPL(iscsi_conn_setup);
3092
3093/**
3094 * iscsi_conn_teardown - teardown iscsi connection
3095 * @cls_conn: iscsi class connection
3096 *
3097 * TODO: we may need to make this into a two step process
3098 * like scsi-mls remove + put host
3099 */
3100void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
3101{
3102	struct iscsi_conn *conn = cls_conn->dd_data;
3103	struct iscsi_session *session = conn->session;
 
3104
3105	del_timer_sync(&conn->transport_timer);
3106
3107	mutex_lock(&session->eh_mutex);
3108	spin_lock_bh(&session->frwd_lock);
3109	conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
3110	if (session->leadconn == conn) {
3111		/*
3112		 * leading connection? then give up on recovery.
3113		 */
3114		session->state = ISCSI_STATE_TERMINATE;
3115		wake_up(&session->ehwait);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3116	}
3117	spin_unlock_bh(&session->frwd_lock);
3118
3119	/* flush queued up work because we free the connection below */
3120	iscsi_suspend_tx(conn);
3121
3122	spin_lock_bh(&session->frwd_lock);
3123	free_pages((unsigned long) conn->data,
3124		   get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
3125	kfree(conn->persistent_address);
3126	kfree(conn->local_ipaddr);
3127	/* regular RX path uses back_lock */
3128	spin_lock_bh(&session->back_lock);
3129	kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
3130		    sizeof(void*));
3131	spin_unlock_bh(&session->back_lock);
3132	if (session->leadconn == conn)
3133		session->leadconn = NULL;
3134	spin_unlock_bh(&session->frwd_lock);
3135	mutex_unlock(&session->eh_mutex);
3136
3137	iscsi_destroy_conn(cls_conn);
3138}
3139EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
3140
3141int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
3142{
3143	struct iscsi_conn *conn = cls_conn->dd_data;
3144	struct iscsi_session *session = conn->session;
3145
3146	if (!session) {
3147		iscsi_conn_printk(KERN_ERR, conn,
3148				  "can't start unbound connection\n");
3149		return -EPERM;
3150	}
3151
3152	if ((session->imm_data_en || !session->initial_r2t_en) &&
3153	     session->first_burst > session->max_burst) {
3154		iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
3155				  "first_burst %d max_burst %d\n",
3156				  session->first_burst, session->max_burst);
3157		return -EINVAL;
3158	}
3159
3160	if (conn->ping_timeout && !conn->recv_timeout) {
3161		iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
3162				  "zero. Using 5 seconds\n.");
3163		conn->recv_timeout = 5;
3164	}
3165
3166	if (conn->recv_timeout && !conn->ping_timeout) {
3167		iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
3168				  "zero. Using 5 seconds.\n");
3169		conn->ping_timeout = 5;
3170	}
3171
3172	spin_lock_bh(&session->frwd_lock);
3173	conn->c_stage = ISCSI_CONN_STARTED;
3174	session->state = ISCSI_STATE_LOGGED_IN;
3175	session->queued_cmdsn = session->cmdsn;
3176
3177	conn->last_recv = jiffies;
3178	conn->last_ping = jiffies;
3179	if (conn->recv_timeout && conn->ping_timeout)
3180		mod_timer(&conn->transport_timer,
3181			  jiffies + (conn->recv_timeout * HZ));
3182
3183	switch(conn->stop_stage) {
3184	case STOP_CONN_RECOVER:
3185		/*
3186		 * unblock eh_abort() if it is blocked. re-try all
3187		 * commands after successful recovery
3188		 */
3189		conn->stop_stage = 0;
3190		session->tmf_state = TMF_INITIAL;
3191		session->age++;
3192		if (session->age == 16)
3193			session->age = 0;
3194		break;
3195	case STOP_CONN_TERM:
3196		conn->stop_stage = 0;
3197		break;
3198	default:
3199		break;
3200	}
3201	spin_unlock_bh(&session->frwd_lock);
3202
3203	iscsi_unblock_session(session->cls_session);
3204	wake_up(&session->ehwait);
3205	return 0;
3206}
3207EXPORT_SYMBOL_GPL(iscsi_conn_start);
3208
3209static void
3210fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn)
3211{
3212	struct iscsi_task *task;
3213	int i, state;
3214
3215	for (i = 0; i < conn->session->cmds_max; i++) {
3216		task = conn->session->cmds[i];
3217		if (task->sc)
3218			continue;
3219
3220		if (task->state == ISCSI_TASK_FREE)
3221			continue;
3222
3223		ISCSI_DBG_SESSION(conn->session,
3224				  "failing mgmt itt 0x%x state %d\n",
3225				  task->itt, task->state);
3226
3227		spin_lock_bh(&session->back_lock);
3228		if (cleanup_queued_task(task)) {
3229			spin_unlock_bh(&session->back_lock);
3230			continue;
3231		}
3232
3233		state = ISCSI_TASK_ABRT_SESS_RECOV;
3234		if (task->state == ISCSI_TASK_PENDING)
3235			state = ISCSI_TASK_COMPLETED;
3236		iscsi_complete_task(task, state);
3237		spin_unlock_bh(&session->back_lock);
3238	}
3239}
3240
3241void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
 
3242{
3243	struct iscsi_conn *conn = cls_conn->dd_data;
3244	struct iscsi_session *session = conn->session;
3245	int old_stop_stage;
3246
3247	mutex_lock(&session->eh_mutex);
3248	spin_lock_bh(&session->frwd_lock);
3249	if (conn->stop_stage == STOP_CONN_TERM) {
3250		spin_unlock_bh(&session->frwd_lock);
3251		mutex_unlock(&session->eh_mutex);
3252		return;
3253	}
3254
3255	/*
3256	 * When this is called for the in_login state, we only want to clean
3257	 * up the login task and connection. We do not need to block and set
3258	 * the recovery state again
3259	 */
3260	if (flag == STOP_CONN_TERM)
3261		session->state = ISCSI_STATE_TERMINATE;
3262	else if (conn->stop_stage != STOP_CONN_RECOVER)
3263		session->state = ISCSI_STATE_IN_RECOVERY;
3264
3265	old_stop_stage = conn->stop_stage;
3266	conn->stop_stage = flag;
3267	spin_unlock_bh(&session->frwd_lock);
3268
3269	del_timer_sync(&conn->transport_timer);
3270	iscsi_suspend_tx(conn);
3271
3272	spin_lock_bh(&session->frwd_lock);
3273	conn->c_stage = ISCSI_CONN_STOPPED;
3274	spin_unlock_bh(&session->frwd_lock);
3275
3276	/*
3277	 * for connection level recovery we should not calculate
3278	 * header digest. conn->hdr_size used for optimization
3279	 * in hdr_extract() and will be re-negotiated at
3280	 * set_param() time.
3281	 */
3282	if (flag == STOP_CONN_RECOVER) {
3283		conn->hdrdgst_en = 0;
3284		conn->datadgst_en = 0;
3285		if (session->state == ISCSI_STATE_IN_RECOVERY &&
3286		    old_stop_stage != STOP_CONN_RECOVER) {
3287			ISCSI_DBG_SESSION(session, "blocking session\n");
3288			iscsi_block_session(session->cls_session);
3289		}
3290	}
3291
3292	/*
3293	 * flush queues.
3294	 */
3295	spin_lock_bh(&session->frwd_lock);
3296	fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED);
3297	fail_mgmt_tasks(session, conn);
3298	memset(&session->tmhdr, 0, sizeof(session->tmhdr));
3299	spin_unlock_bh(&session->frwd_lock);
3300	mutex_unlock(&session->eh_mutex);
3301}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3302EXPORT_SYMBOL_GPL(iscsi_conn_stop);
3303
3304int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
3305		    struct iscsi_cls_conn *cls_conn, int is_leading)
3306{
3307	struct iscsi_session *session = cls_session->dd_data;
3308	struct iscsi_conn *conn = cls_conn->dd_data;
3309
3310	spin_lock_bh(&session->frwd_lock);
3311	if (is_leading)
3312		session->leadconn = conn;
3313	spin_unlock_bh(&session->frwd_lock);
3314
3315	/*
3316	 * The target could have reduced it's window size between logins, so
3317	 * we have to reset max/exp cmdsn so we can see the new values.
3318	 */
3319	spin_lock_bh(&session->back_lock);
3320	session->max_cmdsn = session->exp_cmdsn = session->cmdsn + 1;
3321	spin_unlock_bh(&session->back_lock);
3322	/*
3323	 * Unblock xmitworker(), Login Phase will pass through.
3324	 */
3325	clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
3326	clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
3327	return 0;
3328}
3329EXPORT_SYMBOL_GPL(iscsi_conn_bind);
3330
3331int iscsi_switch_str_param(char **param, char *new_val_buf)
3332{
3333	char *new_val;
3334
3335	if (*param) {
3336		if (!strcmp(*param, new_val_buf))
3337			return 0;
3338	}
3339
3340	new_val = kstrdup(new_val_buf, GFP_NOIO);
3341	if (!new_val)
3342		return -ENOMEM;
3343
3344	kfree(*param);
3345	*param = new_val;
3346	return 0;
3347}
3348EXPORT_SYMBOL_GPL(iscsi_switch_str_param);
3349
3350int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
3351		    enum iscsi_param param, char *buf, int buflen)
3352{
3353	struct iscsi_conn *conn = cls_conn->dd_data;
3354	struct iscsi_session *session = conn->session;
3355	int val;
3356
3357	switch(param) {
3358	case ISCSI_PARAM_FAST_ABORT:
3359		sscanf(buf, "%d", &session->fast_abort);
3360		break;
3361	case ISCSI_PARAM_ABORT_TMO:
3362		sscanf(buf, "%d", &session->abort_timeout);
3363		break;
3364	case ISCSI_PARAM_LU_RESET_TMO:
3365		sscanf(buf, "%d", &session->lu_reset_timeout);
3366		break;
3367	case ISCSI_PARAM_TGT_RESET_TMO:
3368		sscanf(buf, "%d", &session->tgt_reset_timeout);
3369		break;
3370	case ISCSI_PARAM_PING_TMO:
3371		sscanf(buf, "%d", &conn->ping_timeout);
3372		break;
3373	case ISCSI_PARAM_RECV_TMO:
3374		sscanf(buf, "%d", &conn->recv_timeout);
3375		break;
3376	case ISCSI_PARAM_MAX_RECV_DLENGTH:
3377		sscanf(buf, "%d", &conn->max_recv_dlength);
3378		break;
3379	case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3380		sscanf(buf, "%d", &conn->max_xmit_dlength);
3381		break;
3382	case ISCSI_PARAM_HDRDGST_EN:
3383		sscanf(buf, "%d", &conn->hdrdgst_en);
3384		break;
3385	case ISCSI_PARAM_DATADGST_EN:
3386		sscanf(buf, "%d", &conn->datadgst_en);
3387		break;
3388	case ISCSI_PARAM_INITIAL_R2T_EN:
3389		sscanf(buf, "%d", &session->initial_r2t_en);
3390		break;
3391	case ISCSI_PARAM_MAX_R2T:
3392		sscanf(buf, "%hu", &session->max_r2t);
3393		break;
3394	case ISCSI_PARAM_IMM_DATA_EN:
3395		sscanf(buf, "%d", &session->imm_data_en);
3396		break;
3397	case ISCSI_PARAM_FIRST_BURST:
3398		sscanf(buf, "%d", &session->first_burst);
3399		break;
3400	case ISCSI_PARAM_MAX_BURST:
3401		sscanf(buf, "%d", &session->max_burst);
3402		break;
3403	case ISCSI_PARAM_PDU_INORDER_EN:
3404		sscanf(buf, "%d", &session->pdu_inorder_en);
3405		break;
3406	case ISCSI_PARAM_DATASEQ_INORDER_EN:
3407		sscanf(buf, "%d", &session->dataseq_inorder_en);
3408		break;
3409	case ISCSI_PARAM_ERL:
3410		sscanf(buf, "%d", &session->erl);
3411		break;
 
 
 
 
 
 
 
 
3412	case ISCSI_PARAM_EXP_STATSN:
3413		sscanf(buf, "%u", &conn->exp_statsn);
3414		break;
3415	case ISCSI_PARAM_USERNAME:
3416		return iscsi_switch_str_param(&session->username, buf);
3417	case ISCSI_PARAM_USERNAME_IN:
3418		return iscsi_switch_str_param(&session->username_in, buf);
3419	case ISCSI_PARAM_PASSWORD:
3420		return iscsi_switch_str_param(&session->password, buf);
3421	case ISCSI_PARAM_PASSWORD_IN:
3422		return iscsi_switch_str_param(&session->password_in, buf);
3423	case ISCSI_PARAM_TARGET_NAME:
3424		return iscsi_switch_str_param(&session->targetname, buf);
3425	case ISCSI_PARAM_TARGET_ALIAS:
3426		return iscsi_switch_str_param(&session->targetalias, buf);
3427	case ISCSI_PARAM_TPGT:
3428		sscanf(buf, "%d", &session->tpgt);
3429		break;
3430	case ISCSI_PARAM_PERSISTENT_PORT:
3431		sscanf(buf, "%d", &conn->persistent_port);
3432		break;
3433	case ISCSI_PARAM_PERSISTENT_ADDRESS:
3434		return iscsi_switch_str_param(&conn->persistent_address, buf);
3435	case ISCSI_PARAM_IFACE_NAME:
3436		return iscsi_switch_str_param(&session->ifacename, buf);
3437	case ISCSI_PARAM_INITIATOR_NAME:
3438		return iscsi_switch_str_param(&session->initiatorname, buf);
3439	case ISCSI_PARAM_BOOT_ROOT:
3440		return iscsi_switch_str_param(&session->boot_root, buf);
3441	case ISCSI_PARAM_BOOT_NIC:
3442		return iscsi_switch_str_param(&session->boot_nic, buf);
3443	case ISCSI_PARAM_BOOT_TARGET:
3444		return iscsi_switch_str_param(&session->boot_target, buf);
3445	case ISCSI_PARAM_PORTAL_TYPE:
3446		return iscsi_switch_str_param(&session->portal_type, buf);
3447	case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3448		return iscsi_switch_str_param(&session->discovery_parent_type,
3449					      buf);
3450	case ISCSI_PARAM_DISCOVERY_SESS:
3451		sscanf(buf, "%d", &val);
3452		session->discovery_sess = !!val;
3453		break;
3454	case ISCSI_PARAM_LOCAL_IPADDR:
3455		return iscsi_switch_str_param(&conn->local_ipaddr, buf);
3456	default:
3457		return -ENOSYS;
3458	}
3459
3460	return 0;
3461}
3462EXPORT_SYMBOL_GPL(iscsi_set_param);
3463
3464int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
3465			    enum iscsi_param param, char *buf)
3466{
3467	struct iscsi_session *session = cls_session->dd_data;
3468	int len;
3469
3470	switch(param) {
3471	case ISCSI_PARAM_FAST_ABORT:
3472		len = sysfs_emit(buf, "%d\n", session->fast_abort);
3473		break;
3474	case ISCSI_PARAM_ABORT_TMO:
3475		len = sysfs_emit(buf, "%d\n", session->abort_timeout);
3476		break;
3477	case ISCSI_PARAM_LU_RESET_TMO:
3478		len = sysfs_emit(buf, "%d\n", session->lu_reset_timeout);
3479		break;
3480	case ISCSI_PARAM_TGT_RESET_TMO:
3481		len = sysfs_emit(buf, "%d\n", session->tgt_reset_timeout);
3482		break;
3483	case ISCSI_PARAM_INITIAL_R2T_EN:
3484		len = sysfs_emit(buf, "%d\n", session->initial_r2t_en);
3485		break;
3486	case ISCSI_PARAM_MAX_R2T:
3487		len = sysfs_emit(buf, "%hu\n", session->max_r2t);
3488		break;
3489	case ISCSI_PARAM_IMM_DATA_EN:
3490		len = sysfs_emit(buf, "%d\n", session->imm_data_en);
3491		break;
3492	case ISCSI_PARAM_FIRST_BURST:
3493		len = sysfs_emit(buf, "%u\n", session->first_burst);
3494		break;
3495	case ISCSI_PARAM_MAX_BURST:
3496		len = sysfs_emit(buf, "%u\n", session->max_burst);
3497		break;
3498	case ISCSI_PARAM_PDU_INORDER_EN:
3499		len = sysfs_emit(buf, "%d\n", session->pdu_inorder_en);
3500		break;
3501	case ISCSI_PARAM_DATASEQ_INORDER_EN:
3502		len = sysfs_emit(buf, "%d\n", session->dataseq_inorder_en);
3503		break;
3504	case ISCSI_PARAM_DEF_TASKMGMT_TMO:
3505		len = sysfs_emit(buf, "%d\n", session->def_taskmgmt_tmo);
3506		break;
3507	case ISCSI_PARAM_ERL:
3508		len = sysfs_emit(buf, "%d\n", session->erl);
3509		break;
3510	case ISCSI_PARAM_TARGET_NAME:
3511		len = sysfs_emit(buf, "%s\n", session->targetname);
3512		break;
3513	case ISCSI_PARAM_TARGET_ALIAS:
3514		len = sysfs_emit(buf, "%s\n", session->targetalias);
3515		break;
3516	case ISCSI_PARAM_TPGT:
3517		len = sysfs_emit(buf, "%d\n", session->tpgt);
3518		break;
3519	case ISCSI_PARAM_USERNAME:
3520		len = sysfs_emit(buf, "%s\n", session->username);
3521		break;
3522	case ISCSI_PARAM_USERNAME_IN:
3523		len = sysfs_emit(buf, "%s\n", session->username_in);
3524		break;
3525	case ISCSI_PARAM_PASSWORD:
3526		len = sysfs_emit(buf, "%s\n", session->password);
3527		break;
3528	case ISCSI_PARAM_PASSWORD_IN:
3529		len = sysfs_emit(buf, "%s\n", session->password_in);
3530		break;
3531	case ISCSI_PARAM_IFACE_NAME:
3532		len = sysfs_emit(buf, "%s\n", session->ifacename);
3533		break;
3534	case ISCSI_PARAM_INITIATOR_NAME:
3535		len = sysfs_emit(buf, "%s\n", session->initiatorname);
3536		break;
3537	case ISCSI_PARAM_BOOT_ROOT:
3538		len = sysfs_emit(buf, "%s\n", session->boot_root);
3539		break;
3540	case ISCSI_PARAM_BOOT_NIC:
3541		len = sysfs_emit(buf, "%s\n", session->boot_nic);
3542		break;
3543	case ISCSI_PARAM_BOOT_TARGET:
3544		len = sysfs_emit(buf, "%s\n", session->boot_target);
3545		break;
3546	case ISCSI_PARAM_AUTO_SND_TGT_DISABLE:
3547		len = sysfs_emit(buf, "%u\n", session->auto_snd_tgt_disable);
3548		break;
3549	case ISCSI_PARAM_DISCOVERY_SESS:
3550		len = sysfs_emit(buf, "%u\n", session->discovery_sess);
3551		break;
3552	case ISCSI_PARAM_PORTAL_TYPE:
3553		len = sysfs_emit(buf, "%s\n", session->portal_type);
3554		break;
3555	case ISCSI_PARAM_CHAP_AUTH_EN:
3556		len = sysfs_emit(buf, "%u\n", session->chap_auth_en);
3557		break;
3558	case ISCSI_PARAM_DISCOVERY_LOGOUT_EN:
3559		len = sysfs_emit(buf, "%u\n", session->discovery_logout_en);
3560		break;
3561	case ISCSI_PARAM_BIDI_CHAP_EN:
3562		len = sysfs_emit(buf, "%u\n", session->bidi_chap_en);
3563		break;
3564	case ISCSI_PARAM_DISCOVERY_AUTH_OPTIONAL:
3565		len = sysfs_emit(buf, "%u\n", session->discovery_auth_optional);
3566		break;
3567	case ISCSI_PARAM_DEF_TIME2WAIT:
3568		len = sysfs_emit(buf, "%d\n", session->time2wait);
3569		break;
3570	case ISCSI_PARAM_DEF_TIME2RETAIN:
3571		len = sysfs_emit(buf, "%d\n", session->time2retain);
3572		break;
3573	case ISCSI_PARAM_TSID:
3574		len = sysfs_emit(buf, "%u\n", session->tsid);
3575		break;
3576	case ISCSI_PARAM_ISID:
3577		len = sysfs_emit(buf, "%02x%02x%02x%02x%02x%02x\n",
3578			      session->isid[0], session->isid[1],
3579			      session->isid[2], session->isid[3],
3580			      session->isid[4], session->isid[5]);
3581		break;
3582	case ISCSI_PARAM_DISCOVERY_PARENT_IDX:
3583		len = sysfs_emit(buf, "%u\n", session->discovery_parent_idx);
3584		break;
3585	case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3586		if (session->discovery_parent_type)
3587			len = sysfs_emit(buf, "%s\n",
3588				      session->discovery_parent_type);
3589		else
3590			len = sysfs_emit(buf, "\n");
3591		break;
3592	default:
3593		return -ENOSYS;
3594	}
3595
3596	return len;
3597}
3598EXPORT_SYMBOL_GPL(iscsi_session_get_param);
3599
3600int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
3601			      enum iscsi_param param, char *buf)
3602{
3603	struct sockaddr_in6 *sin6 = NULL;
3604	struct sockaddr_in *sin = NULL;
3605	int len;
3606
3607	switch (addr->ss_family) {
3608	case AF_INET:
3609		sin = (struct sockaddr_in *)addr;
3610		break;
3611	case AF_INET6:
3612		sin6 = (struct sockaddr_in6 *)addr;
3613		break;
3614	default:
3615		return -EINVAL;
3616	}
3617
3618	switch (param) {
3619	case ISCSI_PARAM_CONN_ADDRESS:
3620	case ISCSI_HOST_PARAM_IPADDRESS:
3621		if (sin)
3622			len = sysfs_emit(buf, "%pI4\n", &sin->sin_addr.s_addr);
3623		else
3624			len = sysfs_emit(buf, "%pI6\n", &sin6->sin6_addr);
3625		break;
3626	case ISCSI_PARAM_CONN_PORT:
3627	case ISCSI_PARAM_LOCAL_PORT:
3628		if (sin)
3629			len = sysfs_emit(buf, "%hu\n", be16_to_cpu(sin->sin_port));
3630		else
3631			len = sysfs_emit(buf, "%hu\n",
3632				      be16_to_cpu(sin6->sin6_port));
3633		break;
3634	default:
3635		return -EINVAL;
3636	}
3637
3638	return len;
3639}
3640EXPORT_SYMBOL_GPL(iscsi_conn_get_addr_param);
3641
3642int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
3643			 enum iscsi_param param, char *buf)
3644{
3645	struct iscsi_conn *conn = cls_conn->dd_data;
3646	int len;
3647
3648	switch(param) {
3649	case ISCSI_PARAM_PING_TMO:
3650		len = sysfs_emit(buf, "%u\n", conn->ping_timeout);
3651		break;
3652	case ISCSI_PARAM_RECV_TMO:
3653		len = sysfs_emit(buf, "%u\n", conn->recv_timeout);
3654		break;
3655	case ISCSI_PARAM_MAX_RECV_DLENGTH:
3656		len = sysfs_emit(buf, "%u\n", conn->max_recv_dlength);
3657		break;
3658	case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3659		len = sysfs_emit(buf, "%u\n", conn->max_xmit_dlength);
3660		break;
3661	case ISCSI_PARAM_HDRDGST_EN:
3662		len = sysfs_emit(buf, "%d\n", conn->hdrdgst_en);
3663		break;
3664	case ISCSI_PARAM_DATADGST_EN:
3665		len = sysfs_emit(buf, "%d\n", conn->datadgst_en);
3666		break;
3667	case ISCSI_PARAM_IFMARKER_EN:
3668		len = sysfs_emit(buf, "%d\n", conn->ifmarker_en);
3669		break;
3670	case ISCSI_PARAM_OFMARKER_EN:
3671		len = sysfs_emit(buf, "%d\n", conn->ofmarker_en);
3672		break;
3673	case ISCSI_PARAM_EXP_STATSN:
3674		len = sysfs_emit(buf, "%u\n", conn->exp_statsn);
3675		break;
3676	case ISCSI_PARAM_PERSISTENT_PORT:
3677		len = sysfs_emit(buf, "%d\n", conn->persistent_port);
3678		break;
3679	case ISCSI_PARAM_PERSISTENT_ADDRESS:
3680		len = sysfs_emit(buf, "%s\n", conn->persistent_address);
3681		break;
3682	case ISCSI_PARAM_STATSN:
3683		len = sysfs_emit(buf, "%u\n", conn->statsn);
3684		break;
3685	case ISCSI_PARAM_MAX_SEGMENT_SIZE:
3686		len = sysfs_emit(buf, "%u\n", conn->max_segment_size);
3687		break;
3688	case ISCSI_PARAM_KEEPALIVE_TMO:
3689		len = sysfs_emit(buf, "%u\n", conn->keepalive_tmo);
3690		break;
3691	case ISCSI_PARAM_LOCAL_PORT:
3692		len = sysfs_emit(buf, "%u\n", conn->local_port);
3693		break;
3694	case ISCSI_PARAM_TCP_TIMESTAMP_STAT:
3695		len = sysfs_emit(buf, "%u\n", conn->tcp_timestamp_stat);
3696		break;
3697	case ISCSI_PARAM_TCP_NAGLE_DISABLE:
3698		len = sysfs_emit(buf, "%u\n", conn->tcp_nagle_disable);
3699		break;
3700	case ISCSI_PARAM_TCP_WSF_DISABLE:
3701		len = sysfs_emit(buf, "%u\n", conn->tcp_wsf_disable);
3702		break;
3703	case ISCSI_PARAM_TCP_TIMER_SCALE:
3704		len = sysfs_emit(buf, "%u\n", conn->tcp_timer_scale);
3705		break;
3706	case ISCSI_PARAM_TCP_TIMESTAMP_EN:
3707		len = sysfs_emit(buf, "%u\n", conn->tcp_timestamp_en);
3708		break;
3709	case ISCSI_PARAM_IP_FRAGMENT_DISABLE:
3710		len = sysfs_emit(buf, "%u\n", conn->fragment_disable);
3711		break;
3712	case ISCSI_PARAM_IPV4_TOS:
3713		len = sysfs_emit(buf, "%u\n", conn->ipv4_tos);
3714		break;
3715	case ISCSI_PARAM_IPV6_TC:
3716		len = sysfs_emit(buf, "%u\n", conn->ipv6_traffic_class);
3717		break;
3718	case ISCSI_PARAM_IPV6_FLOW_LABEL:
3719		len = sysfs_emit(buf, "%u\n", conn->ipv6_flow_label);
3720		break;
3721	case ISCSI_PARAM_IS_FW_ASSIGNED_IPV6:
3722		len = sysfs_emit(buf, "%u\n", conn->is_fw_assigned_ipv6);
3723		break;
3724	case ISCSI_PARAM_TCP_XMIT_WSF:
3725		len = sysfs_emit(buf, "%u\n", conn->tcp_xmit_wsf);
3726		break;
3727	case ISCSI_PARAM_TCP_RECV_WSF:
3728		len = sysfs_emit(buf, "%u\n", conn->tcp_recv_wsf);
3729		break;
3730	case ISCSI_PARAM_LOCAL_IPADDR:
3731		len = sysfs_emit(buf, "%s\n", conn->local_ipaddr);
3732		break;
3733	default:
3734		return -ENOSYS;
3735	}
3736
3737	return len;
3738}
3739EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
3740
3741int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3742			 char *buf)
3743{
3744	struct iscsi_host *ihost = shost_priv(shost);
3745	int len;
3746
3747	switch (param) {
3748	case ISCSI_HOST_PARAM_NETDEV_NAME:
3749		len = sysfs_emit(buf, "%s\n", ihost->netdev);
3750		break;
3751	case ISCSI_HOST_PARAM_HWADDRESS:
3752		len = sysfs_emit(buf, "%s\n", ihost->hwaddress);
3753		break;
3754	case ISCSI_HOST_PARAM_INITIATOR_NAME:
3755		len = sysfs_emit(buf, "%s\n", ihost->initiatorname);
3756		break;
3757	default:
3758		return -ENOSYS;
3759	}
3760
3761	return len;
3762}
3763EXPORT_SYMBOL_GPL(iscsi_host_get_param);
3764
3765int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3766			 char *buf, int buflen)
3767{
3768	struct iscsi_host *ihost = shost_priv(shost);
3769
3770	switch (param) {
3771	case ISCSI_HOST_PARAM_NETDEV_NAME:
3772		return iscsi_switch_str_param(&ihost->netdev, buf);
3773	case ISCSI_HOST_PARAM_HWADDRESS:
3774		return iscsi_switch_str_param(&ihost->hwaddress, buf);
3775	case ISCSI_HOST_PARAM_INITIATOR_NAME:
3776		return iscsi_switch_str_param(&ihost->initiatorname, buf);
3777	default:
3778		return -ENOSYS;
3779	}
3780
3781	return 0;
3782}
3783EXPORT_SYMBOL_GPL(iscsi_host_set_param);
3784
3785MODULE_AUTHOR("Mike Christie");
3786MODULE_DESCRIPTION("iSCSI library functions");
3787MODULE_LICENSE("GPL");
v3.1
 
   1/*
   2 * iSCSI lib functions
   3 *
   4 * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
   5 * Copyright (C) 2004 - 2006 Mike Christie
   6 * Copyright (C) 2004 - 2005 Dmitry Yusupov
   7 * Copyright (C) 2004 - 2005 Alex Aizman
   8 * maintained by open-iscsi@googlegroups.com
   9 *
  10 * This program is free software; you can redistribute it and/or modify
  11 * it under the terms of the GNU General Public License as published by
  12 * the Free Software Foundation; either version 2 of the License, or
  13 * (at your option) any later version.
  14 *
  15 * This program is distributed in the hope that it will be useful,
  16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 * GNU General Public License for more details.
  19 *
  20 * You should have received a copy of the GNU General Public License
  21 * along with this program; if not, write to the Free Software
  22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23 */
  24#include <linux/types.h>
  25#include <linux/kfifo.h>
  26#include <linux/delay.h>
  27#include <linux/log2.h>
  28#include <linux/slab.h>
 
 
  29#include <asm/unaligned.h>
  30#include <net/tcp.h>
  31#include <scsi/scsi_cmnd.h>
  32#include <scsi/scsi_device.h>
  33#include <scsi/scsi_eh.h>
  34#include <scsi/scsi_tcq.h>
  35#include <scsi/scsi_host.h>
  36#include <scsi/scsi.h>
  37#include <scsi/iscsi_proto.h>
  38#include <scsi/scsi_transport.h>
  39#include <scsi/scsi_transport_iscsi.h>
  40#include <scsi/libiscsi.h>
 
  41
  42static int iscsi_dbg_lib_conn;
  43module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
  44		   S_IRUGO | S_IWUSR);
  45MODULE_PARM_DESC(debug_libiscsi_conn,
  46		 "Turn on debugging for connections in libiscsi module. "
  47		 "Set to 1 to turn on, and zero to turn off. Default is off.");
  48
  49static int iscsi_dbg_lib_session;
  50module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int,
  51		   S_IRUGO | S_IWUSR);
  52MODULE_PARM_DESC(debug_libiscsi_session,
  53		 "Turn on debugging for sessions in libiscsi module. "
  54		 "Set to 1 to turn on, and zero to turn off. Default is off.");
  55
  56static int iscsi_dbg_lib_eh;
  57module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int,
  58		   S_IRUGO | S_IWUSR);
  59MODULE_PARM_DESC(debug_libiscsi_eh,
  60		 "Turn on debugging for error handling in libiscsi module. "
  61		 "Set to 1 to turn on, and zero to turn off. Default is off.");
  62
  63#define ISCSI_DBG_CONN(_conn, dbg_fmt, arg...)			\
  64	do {							\
  65		if (iscsi_dbg_lib_conn)				\
  66			iscsi_conn_printk(KERN_INFO, _conn,	\
  67					     "%s " dbg_fmt,	\
  68					     __func__, ##arg);	\
 
 
 
  69	} while (0);
  70
  71#define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...)			\
  72	do {								\
  73		if (iscsi_dbg_lib_session)				\
  74			iscsi_session_printk(KERN_INFO, _session,	\
  75					     "%s " dbg_fmt,		\
  76					     __func__, ##arg);		\
 
 
 
  77	} while (0);
  78
  79#define ISCSI_DBG_EH(_session, dbg_fmt, arg...)				\
  80	do {								\
  81		if (iscsi_dbg_lib_eh)					\
  82			iscsi_session_printk(KERN_INFO, _session,	\
  83					     "%s " dbg_fmt,		\
  84					     __func__, ##arg);		\
 
 
 
  85	} while (0);
  86
  87inline void iscsi_conn_queue_work(struct iscsi_conn *conn)
  88{
  89	struct Scsi_Host *shost = conn->session->host;
  90	struct iscsi_host *ihost = shost_priv(shost);
  91
  92	if (ihost->workq)
  93		queue_work(ihost->workq, &conn->xmitwork);
  94}
  95EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
  96
  97static void __iscsi_update_cmdsn(struct iscsi_session *session,
  98				 uint32_t exp_cmdsn, uint32_t max_cmdsn)
  99{
 100	/*
 101	 * standard specifies this check for when to update expected and
 102	 * max sequence numbers
 103	 */
 104	if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
 105		return;
 106
 107	if (exp_cmdsn != session->exp_cmdsn &&
 108	    !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
 109		session->exp_cmdsn = exp_cmdsn;
 110
 111	if (max_cmdsn != session->max_cmdsn &&
 112	    !iscsi_sna_lt(max_cmdsn, session->max_cmdsn)) {
 113		session->max_cmdsn = max_cmdsn;
 114		/*
 115		 * if the window closed with IO queued, then kick the
 116		 * xmit thread
 117		 */
 118		if (!list_empty(&session->leadconn->cmdqueue) ||
 119		    !list_empty(&session->leadconn->mgmtqueue))
 120			iscsi_conn_queue_work(session->leadconn);
 121	}
 122}
 123
 124void iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
 125{
 126	__iscsi_update_cmdsn(session, be32_to_cpu(hdr->exp_cmdsn),
 127			     be32_to_cpu(hdr->max_cmdsn));
 128}
 129EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
 130
 131/**
 132 * iscsi_prep_data_out_pdu - initialize Data-Out
 133 * @task: scsi command task
 134 * @r2t: R2T info
 135 * @hdr: iscsi data in pdu
 136 *
 137 * Notes:
 138 *	Initialize Data-Out within this R2T sequence and finds
 139 *	proper data_offset within this SCSI command.
 140 *
 141 *	This function is called with connection lock taken.
 142 **/
 143void iscsi_prep_data_out_pdu(struct iscsi_task *task, struct iscsi_r2t_info *r2t,
 144			   struct iscsi_data *hdr)
 145{
 146	struct iscsi_conn *conn = task->conn;
 147	unsigned int left = r2t->data_length - r2t->sent;
 148
 149	task->hdr_len = sizeof(struct iscsi_data);
 150
 151	memset(hdr, 0, sizeof(struct iscsi_data));
 152	hdr->ttt = r2t->ttt;
 153	hdr->datasn = cpu_to_be32(r2t->datasn);
 154	r2t->datasn++;
 155	hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
 156	hdr->lun = task->lun;
 157	hdr->itt = task->hdr_itt;
 158	hdr->exp_statsn = r2t->exp_statsn;
 159	hdr->offset = cpu_to_be32(r2t->data_offset + r2t->sent);
 160	if (left > conn->max_xmit_dlength) {
 161		hton24(hdr->dlength, conn->max_xmit_dlength);
 162		r2t->data_count = conn->max_xmit_dlength;
 163		hdr->flags = 0;
 164	} else {
 165		hton24(hdr->dlength, left);
 166		r2t->data_count = left;
 167		hdr->flags = ISCSI_FLAG_CMD_FINAL;
 168	}
 169	conn->dataout_pdus_cnt++;
 170}
 171EXPORT_SYMBOL_GPL(iscsi_prep_data_out_pdu);
 172
 173static int iscsi_add_hdr(struct iscsi_task *task, unsigned len)
 174{
 175	unsigned exp_len = task->hdr_len + len;
 176
 177	if (exp_len > task->hdr_max) {
 178		WARN_ON(1);
 179		return -EINVAL;
 180	}
 181
 182	WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
 183	task->hdr_len = exp_len;
 184	return 0;
 185}
 186
 187/*
 188 * make an extended cdb AHS
 189 */
 190static int iscsi_prep_ecdb_ahs(struct iscsi_task *task)
 191{
 192	struct scsi_cmnd *cmd = task->sc;
 193	unsigned rlen, pad_len;
 194	unsigned short ahslength;
 195	struct iscsi_ecdb_ahdr *ecdb_ahdr;
 196	int rc;
 197
 198	ecdb_ahdr = iscsi_next_hdr(task);
 199	rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
 200
 201	BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
 202	ahslength = rlen + sizeof(ecdb_ahdr->reserved);
 203
 204	pad_len = iscsi_padding(rlen);
 205
 206	rc = iscsi_add_hdr(task, sizeof(ecdb_ahdr->ahslength) +
 207	                   sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
 208	if (rc)
 209		return rc;
 210
 211	if (pad_len)
 212		memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
 213
 214	ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
 215	ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
 216	ecdb_ahdr->reserved = 0;
 217	memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
 218
 219	ISCSI_DBG_SESSION(task->conn->session,
 220			  "iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
 221		          "rlen %d pad_len %d ahs_length %d iscsi_headers_size "
 222		          "%u\n", cmd->cmd_len, rlen, pad_len, ahslength,
 223		          task->hdr_len);
 224	return 0;
 225}
 226
 227static int iscsi_prep_bidi_ahs(struct iscsi_task *task)
 228{
 229	struct scsi_cmnd *sc = task->sc;
 230	struct iscsi_rlength_ahdr *rlen_ahdr;
 231	int rc;
 232
 233	rlen_ahdr = iscsi_next_hdr(task);
 234	rc = iscsi_add_hdr(task, sizeof(*rlen_ahdr));
 235	if (rc)
 236		return rc;
 237
 238	rlen_ahdr->ahslength =
 239		cpu_to_be16(sizeof(rlen_ahdr->read_length) +
 240						  sizeof(rlen_ahdr->reserved));
 241	rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
 242	rlen_ahdr->reserved = 0;
 243	rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
 244
 245	ISCSI_DBG_SESSION(task->conn->session,
 246			  "bidi-in rlen_ahdr->read_length(%d) "
 247		          "rlen_ahdr->ahslength(%d)\n",
 248		          be32_to_cpu(rlen_ahdr->read_length),
 249		          be16_to_cpu(rlen_ahdr->ahslength));
 250	return 0;
 251}
 252
 253/**
 254 * iscsi_check_tmf_restrictions - check if a task is affected by TMF
 255 * @task: iscsi task
 256 * @opcode: opcode to check for
 257 *
 258 * During TMF a task has to be checked if it's affected.
 259 * All unrelated I/O can be passed through, but I/O to the
 260 * affected LUN should be restricted.
 261 * If 'fast_abort' is set we won't be sending any I/O to the
 262 * affected LUN.
 263 * Otherwise the target is waiting for all TTTs to be completed,
 264 * so we have to send all outstanding Data-Out PDUs to the target.
 265 */
 266static int iscsi_check_tmf_restrictions(struct iscsi_task *task, int opcode)
 267{
 268	struct iscsi_conn *conn = task->conn;
 269	struct iscsi_tm *tmf = &conn->tmhdr;
 270	unsigned int hdr_lun;
 271
 272	if (conn->tmf_state == TMF_INITIAL)
 273		return 0;
 274
 275	if ((tmf->opcode & ISCSI_OPCODE_MASK) != ISCSI_OP_SCSI_TMFUNC)
 276		return 0;
 277
 278	switch (ISCSI_TM_FUNC_VALUE(tmf)) {
 279	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
 280		/*
 281		 * Allow PDUs for unrelated LUNs
 282		 */
 283		hdr_lun = scsilun_to_int(&tmf->lun);
 284		if (hdr_lun != task->sc->device->lun)
 285			return 0;
 286		/* fall through */
 287	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
 288		/*
 289		 * Fail all SCSI cmd PDUs
 290		 */
 291		if (opcode != ISCSI_OP_SCSI_DATA_OUT) {
 292			iscsi_conn_printk(KERN_INFO, conn,
 293					  "task [op %x/%x itt "
 294					  "0x%x/0x%x] "
 295					  "rejected.\n",
 296					  task->hdr->opcode, opcode,
 297					  task->itt, task->hdr_itt);
 298			return -EACCES;
 299		}
 300		/*
 301		 * And also all data-out PDUs in response to R2T
 302		 * if fast_abort is set.
 303		 */
 304		if (conn->session->fast_abort) {
 305			iscsi_conn_printk(KERN_INFO, conn,
 306					  "task [op %x/%x itt "
 307					  "0x%x/0x%x] fast abort.\n",
 308					  task->hdr->opcode, opcode,
 309					  task->itt, task->hdr_itt);
 310			return -EACCES;
 311		}
 312		break;
 313	case ISCSI_TM_FUNC_ABORT_TASK:
 314		/*
 315		 * the caller has already checked if the task
 316		 * they want to abort was in the pending queue so if
 317		 * we are here the cmd pdu has gone out already, and
 318		 * we will only hit this for data-outs
 319		 */
 320		if (opcode == ISCSI_OP_SCSI_DATA_OUT &&
 321		    task->hdr_itt == tmf->rtt) {
 322			ISCSI_DBG_SESSION(conn->session,
 323					  "Preventing task %x/%x from sending "
 324					  "data-out due to abort task in "
 325					  "progress\n", task->itt,
 326					  task->hdr_itt);
 327			return -EACCES;
 328		}
 329		break;
 330	}
 331
 332	return 0;
 333}
 334
 335/**
 336 * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
 337 * @task: iscsi task
 338 *
 339 * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
 340 * fields like dlength or final based on how much data it sends
 341 */
 342static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
 343{
 344	struct iscsi_conn *conn = task->conn;
 345	struct iscsi_session *session = conn->session;
 346	struct scsi_cmnd *sc = task->sc;
 347	struct iscsi_scsi_req *hdr;
 348	unsigned hdrlength, cmd_len;
 349	itt_t itt;
 350	int rc;
 351
 352	rc = iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_CMD);
 353	if (rc)
 354		return rc;
 355
 356	if (conn->session->tt->alloc_pdu) {
 357		rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_CMD);
 358		if (rc)
 359			return rc;
 360	}
 361	hdr = (struct iscsi_scsi_req *)task->hdr;
 362	itt = hdr->itt;
 363	memset(hdr, 0, sizeof(*hdr));
 364
 365	if (session->tt->parse_pdu_itt)
 366		hdr->itt = task->hdr_itt = itt;
 367	else
 368		hdr->itt = task->hdr_itt = build_itt(task->itt,
 369						     task->conn->session->age);
 370	task->hdr_len = 0;
 371	rc = iscsi_add_hdr(task, sizeof(*hdr));
 372	if (rc)
 373		return rc;
 374	hdr->opcode = ISCSI_OP_SCSI_CMD;
 375	hdr->flags = ISCSI_ATTR_SIMPLE;
 376	int_to_scsilun(sc->device->lun, &hdr->lun);
 377	task->lun = hdr->lun;
 378	hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
 379	cmd_len = sc->cmd_len;
 380	if (cmd_len < ISCSI_CDB_SIZE)
 381		memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
 382	else if (cmd_len > ISCSI_CDB_SIZE) {
 383		rc = iscsi_prep_ecdb_ahs(task);
 384		if (rc)
 385			return rc;
 386		cmd_len = ISCSI_CDB_SIZE;
 387	}
 388	memcpy(hdr->cdb, sc->cmnd, cmd_len);
 389
 390	task->imm_count = 0;
 391	if (scsi_bidi_cmnd(sc)) {
 392		hdr->flags |= ISCSI_FLAG_CMD_READ;
 393		rc = iscsi_prep_bidi_ahs(task);
 394		if (rc)
 395			return rc;
 396	}
 397	if (sc->sc_data_direction == DMA_TO_DEVICE) {
 398		unsigned out_len = scsi_out(sc)->length;
 399		struct iscsi_r2t_info *r2t = &task->unsol_r2t;
 400
 401		hdr->data_length = cpu_to_be32(out_len);
 402		hdr->flags |= ISCSI_FLAG_CMD_WRITE;
 403		/*
 404		 * Write counters:
 405		 *
 406		 *	imm_count	bytes to be sent right after
 407		 *			SCSI PDU Header
 408		 *
 409		 *	unsol_count	bytes(as Data-Out) to be sent
 410		 *			without	R2T ack right after
 411		 *			immediate data
 412		 *
 413		 *	r2t data_length bytes to be sent via R2T ack's
 414		 *
 415		 *      pad_count       bytes to be sent as zero-padding
 416		 */
 417		memset(r2t, 0, sizeof(*r2t));
 418
 419		if (session->imm_data_en) {
 420			if (out_len >= session->first_burst)
 421				task->imm_count = min(session->first_burst,
 422							conn->max_xmit_dlength);
 423			else
 424				task->imm_count = min(out_len,
 425							conn->max_xmit_dlength);
 426			hton24(hdr->dlength, task->imm_count);
 427		} else
 428			zero_data(hdr->dlength);
 429
 430		if (!session->initial_r2t_en) {
 431			r2t->data_length = min(session->first_burst, out_len) -
 
 432					       task->imm_count;
 433			r2t->data_offset = task->imm_count;
 434			r2t->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
 435			r2t->exp_statsn = cpu_to_be32(conn->exp_statsn);
 436		}
 437
 438		if (!task->unsol_r2t.data_length)
 439			/* No unsolicit Data-Out's */
 440			hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 441	} else {
 442		hdr->flags |= ISCSI_FLAG_CMD_FINAL;
 443		zero_data(hdr->dlength);
 444		hdr->data_length = cpu_to_be32(scsi_in(sc)->length);
 445
 446		if (sc->sc_data_direction == DMA_FROM_DEVICE)
 447			hdr->flags |= ISCSI_FLAG_CMD_READ;
 448	}
 449
 450	/* calculate size of additional header segments (AHSs) */
 451	hdrlength = task->hdr_len - sizeof(*hdr);
 452
 453	WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
 454	hdrlength /= ISCSI_PAD_LEN;
 455
 456	WARN_ON(hdrlength >= 256);
 457	hdr->hlength = hdrlength & 0xFF;
 458	hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
 459
 460	if (session->tt->init_task && session->tt->init_task(task))
 461		return -EIO;
 462
 463	task->state = ISCSI_TASK_RUNNING;
 464	session->cmdsn++;
 465
 466	conn->scsicmd_pdus_cnt++;
 467	ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
 468			  "itt 0x%x len %d bidi_len %d cmdsn %d win %d]\n",
 469			  scsi_bidi_cmnd(sc) ? "bidirectional" :
 470			  sc->sc_data_direction == DMA_TO_DEVICE ?
 471			  "write" : "read", conn->id, sc, sc->cmnd[0],
 472			  task->itt, scsi_bufflen(sc),
 473			  scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
 474			  session->cmdsn,
 475			  session->max_cmdsn - session->exp_cmdsn + 1);
 476	return 0;
 477}
 478
 479/**
 480 * iscsi_free_task - free a task
 481 * @task: iscsi cmd task
 482 *
 483 * Must be called with session lock.
 484 * This function returns the scsi command to scsi-ml or cleans
 485 * up mgmt tasks then returns the task to the pool.
 486 */
 487static void iscsi_free_task(struct iscsi_task *task)
 488{
 489	struct iscsi_conn *conn = task->conn;
 490	struct iscsi_session *session = conn->session;
 491	struct scsi_cmnd *sc = task->sc;
 492	int oldstate = task->state;
 493
 494	ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
 495			  task->itt, task->state, task->sc);
 496
 497	session->tt->cleanup_task(task);
 498	task->state = ISCSI_TASK_FREE;
 499	task->sc = NULL;
 500	/*
 501	 * login task is preallocated so do not free
 502	 */
 503	if (conn->login_task == task)
 504		return;
 505
 506	kfifo_in(&session->cmdpool.queue, (void*)&task, sizeof(void*));
 507
 508	if (sc) {
 509		task->sc = NULL;
 510		/* SCSI eh reuses commands to verify us */
 511		sc->SCp.ptr = NULL;
 512		/*
 513		 * queue command may call this to free the task, so
 514		 * it will decide how to return sc to scsi-ml.
 515		 */
 516		if (oldstate != ISCSI_TASK_REQUEUE_SCSIQ)
 517			sc->scsi_done(sc);
 518	}
 519}
 520
 521void __iscsi_get_task(struct iscsi_task *task)
 522{
 523	atomic_inc(&task->refcount);
 524}
 525EXPORT_SYMBOL_GPL(__iscsi_get_task);
 526
 527void __iscsi_put_task(struct iscsi_task *task)
 528{
 529	if (atomic_dec_and_test(&task->refcount))
 530		iscsi_free_task(task);
 531}
 532EXPORT_SYMBOL_GPL(__iscsi_put_task);
 533
 534void iscsi_put_task(struct iscsi_task *task)
 535{
 536	struct iscsi_session *session = task->conn->session;
 537
 538	spin_lock_bh(&session->lock);
 
 539	__iscsi_put_task(task);
 540	spin_unlock_bh(&session->lock);
 541}
 542EXPORT_SYMBOL_GPL(iscsi_put_task);
 543
 544/**
 545 * iscsi_complete_task - finish a task
 546 * @task: iscsi cmd task
 547 * @state: state to complete task with
 548 *
 549 * Must be called with session lock.
 550 */
 551static void iscsi_complete_task(struct iscsi_task *task, int state)
 552{
 553	struct iscsi_conn *conn = task->conn;
 554
 555	ISCSI_DBG_SESSION(conn->session,
 556			  "complete task itt 0x%x state %d sc %p\n",
 557			  task->itt, task->state, task->sc);
 558	if (task->state == ISCSI_TASK_COMPLETED ||
 559	    task->state == ISCSI_TASK_ABRT_TMF ||
 560	    task->state == ISCSI_TASK_ABRT_SESS_RECOV ||
 561	    task->state == ISCSI_TASK_REQUEUE_SCSIQ)
 562		return;
 563	WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
 564	task->state = state;
 565
 566	if (!list_empty(&task->running))
 567		list_del_init(&task->running);
 568
 569	if (conn->task == task)
 570		conn->task = NULL;
 571
 572	if (conn->ping_task == task)
 573		conn->ping_task = NULL;
 574
 575	/* release get from queueing */
 576	__iscsi_put_task(task);
 577}
 578
 579/**
 580 * iscsi_complete_scsi_task - finish scsi task normally
 581 * @task: iscsi task for scsi cmd
 582 * @exp_cmdsn: expected cmd sn in cpu format
 583 * @max_cmdsn: max cmd sn in cpu format
 584 *
 585 * This is used when drivers do not need or cannot perform
 586 * lower level pdu processing.
 587 *
 588 * Called with session lock
 589 */
 590void iscsi_complete_scsi_task(struct iscsi_task *task,
 591			      uint32_t exp_cmdsn, uint32_t max_cmdsn)
 592{
 593	struct iscsi_conn *conn = task->conn;
 594
 595	ISCSI_DBG_SESSION(conn->session, "[itt 0x%x]\n", task->itt);
 596
 597	conn->last_recv = jiffies;
 598	__iscsi_update_cmdsn(conn->session, exp_cmdsn, max_cmdsn);
 599	iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 600}
 601EXPORT_SYMBOL_GPL(iscsi_complete_scsi_task);
 602
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 603
 604/*
 605 * session lock must be held and if not called for a task that is
 606 * still pending or from the xmit thread, then xmit thread must
 607 * be suspended.
 608 */
 609static void fail_scsi_task(struct iscsi_task *task, int err)
 610{
 611	struct iscsi_conn *conn = task->conn;
 612	struct scsi_cmnd *sc;
 613	int state;
 614
 615	/*
 616	 * if a command completes and we get a successful tmf response
 617	 * we will hit this because the scsi eh abort code does not take
 618	 * a ref to the task.
 619	 */
 620	sc = task->sc;
 621	if (!sc)
 622		return;
 
 623
 624	if (task->state == ISCSI_TASK_PENDING) {
 625		/*
 626		 * cmd never made it to the xmit thread, so we should not count
 627		 * the cmd in the sequencing
 628		 */
 629		conn->session->queued_cmdsn--;
 630		/* it was never sent so just complete like normal */
 631		state = ISCSI_TASK_COMPLETED;
 632	} else if (err == DID_TRANSPORT_DISRUPTED)
 633		state = ISCSI_TASK_ABRT_SESS_RECOV;
 634	else
 635		state = ISCSI_TASK_ABRT_TMF;
 636
 
 637	sc->result = err << 16;
 638	if (!scsi_bidi_cmnd(sc))
 639		scsi_set_resid(sc, scsi_bufflen(sc));
 640	else {
 641		scsi_out(sc)->resid = scsi_out(sc)->length;
 642		scsi_in(sc)->resid = scsi_in(sc)->length;
 643	}
 644
 645	iscsi_complete_task(task, state);
 
 646}
 647
 648static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
 649				struct iscsi_task *task)
 650{
 651	struct iscsi_session *session = conn->session;
 652	struct iscsi_hdr *hdr = task->hdr;
 653	struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
 654	uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
 655
 656	if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
 657		return -ENOTCONN;
 658
 659	if (opcode != ISCSI_OP_LOGIN && opcode != ISCSI_OP_TEXT)
 660		nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
 661	/*
 662	 * pre-format CmdSN for outgoing PDU.
 663	 */
 664	nop->cmdsn = cpu_to_be32(session->cmdsn);
 665	if (hdr->itt != RESERVED_ITT) {
 666		/*
 667		 * TODO: We always use immediate for normal session pdus.
 668		 * If we start to send tmfs or nops as non-immediate then
 669		 * we should start checking the cmdsn numbers for mgmt tasks.
 670		 *
 671		 * During discovery sessions iscsid sends TEXT as non immediate,
 672		 * but we always only send one PDU at a time.
 673		 */
 674		if (conn->c_stage == ISCSI_CONN_STARTED &&
 675		    !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
 676			session->queued_cmdsn++;
 677			session->cmdsn++;
 678		}
 679	}
 680
 681	if (session->tt->init_task && session->tt->init_task(task))
 682		return -EIO;
 683
 684	if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
 685		session->state = ISCSI_STATE_LOGGING_OUT;
 686
 687	task->state = ISCSI_TASK_RUNNING;
 688	ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x "
 689			  "datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK,
 690			  hdr->itt, task->data_count);
 691	return 0;
 692}
 693
 694static struct iscsi_task *
 695__iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 696		      char *data, uint32_t data_size)
 697{
 698	struct iscsi_session *session = conn->session;
 699	struct iscsi_host *ihost = shost_priv(session->host);
 700	uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
 701	struct iscsi_task *task;
 702	itt_t itt;
 703
 704	if (session->state == ISCSI_STATE_TERMINATE)
 705		return NULL;
 706
 707	if (opcode == ISCSI_OP_LOGIN || opcode == ISCSI_OP_TEXT) {
 708		/*
 709		 * Login and Text are sent serially, in
 710		 * request-followed-by-response sequence.
 711		 * Same task can be used. Same ITT must be used.
 712		 * Note that login_task is preallocated at conn_create().
 713		 */
 714		if (conn->login_task->state != ISCSI_TASK_FREE) {
 715			iscsi_conn_printk(KERN_ERR, conn, "Login/Text in "
 716					  "progress. Cannot start new task.\n");
 717			return NULL;
 718		}
 719
 
 
 
 
 
 720		task = conn->login_task;
 721	} else {
 722		if (session->state != ISCSI_STATE_LOGGED_IN)
 723			return NULL;
 724
 
 
 
 
 
 725		BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
 726		BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
 727
 728		if (!kfifo_out(&session->cmdpool.queue,
 729				 (void*)&task, sizeof(void*)))
 730			return NULL;
 731	}
 732	/*
 733	 * released in complete pdu for task we expect a response for, and
 734	 * released by the lld when it has transmitted the task for
 735	 * pdus we do not expect a response for.
 736	 */
 737	atomic_set(&task->refcount, 1);
 738	task->conn = conn;
 739	task->sc = NULL;
 740	INIT_LIST_HEAD(&task->running);
 741	task->state = ISCSI_TASK_PENDING;
 742
 743	if (data_size) {
 744		memcpy(task->data, data, data_size);
 745		task->data_count = data_size;
 746	} else
 747		task->data_count = 0;
 748
 749	if (conn->session->tt->alloc_pdu) {
 750		if (conn->session->tt->alloc_pdu(task, hdr->opcode)) {
 751			iscsi_conn_printk(KERN_ERR, conn, "Could not allocate "
 752					 "pdu for mgmt task.\n");
 753			goto free_task;
 754		}
 755	}
 756
 757	itt = task->hdr->itt;
 758	task->hdr_len = sizeof(struct iscsi_hdr);
 759	memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr));
 760
 761	if (hdr->itt != RESERVED_ITT) {
 762		if (session->tt->parse_pdu_itt)
 763			task->hdr->itt = itt;
 764		else
 765			task->hdr->itt = build_itt(task->itt,
 766						   task->conn->session->age);
 767	}
 768
 
 
 
 769	if (!ihost->workq) {
 770		if (iscsi_prep_mgmt_task(conn, task))
 771			goto free_task;
 772
 773		if (session->tt->xmit_task(task))
 774			goto free_task;
 775	} else {
 776		list_add_tail(&task->running, &conn->mgmtqueue);
 777		iscsi_conn_queue_work(conn);
 778	}
 779
 780	return task;
 781
 782free_task:
 
 
 783	__iscsi_put_task(task);
 
 784	return NULL;
 785}
 786
 787int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
 788			char *data, uint32_t data_size)
 789{
 790	struct iscsi_conn *conn = cls_conn->dd_data;
 791	struct iscsi_session *session = conn->session;
 792	int err = 0;
 793
 794	spin_lock_bh(&session->lock);
 795	if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
 796		err = -EPERM;
 797	spin_unlock_bh(&session->lock);
 798	return err;
 799}
 800EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
 801
 802/**
 803 * iscsi_cmd_rsp - SCSI Command Response processing
 804 * @conn: iscsi connection
 805 * @hdr: iscsi header
 806 * @task: scsi command task
 807 * @data: cmd data buffer
 808 * @datalen: len of buffer
 809 *
 810 * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
 811 * then completes the command and task.
 812 **/
 813static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 814			       struct iscsi_task *task, char *data,
 815			       int datalen)
 816{
 817	struct iscsi_scsi_rsp *rhdr = (struct iscsi_scsi_rsp *)hdr;
 818	struct iscsi_session *session = conn->session;
 819	struct scsi_cmnd *sc = task->sc;
 820
 821	iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
 822	conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 823
 824	sc->result = (DID_OK << 16) | rhdr->cmd_status;
 825
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 826	if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
 827		sc->result = DID_ERROR << 16;
 828		goto out;
 829	}
 830
 831	if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
 832		uint16_t senselen;
 833
 834		if (datalen < 2) {
 835invalid_datalen:
 836			iscsi_conn_printk(KERN_ERR,  conn,
 837					 "Got CHECK_CONDITION but invalid data "
 838					 "buffer size of %d\n", datalen);
 839			sc->result = DID_BAD_TARGET << 16;
 840			goto out;
 841		}
 842
 843		senselen = get_unaligned_be16(data);
 844		if (datalen < senselen)
 845			goto invalid_datalen;
 846
 847		memcpy(sc->sense_buffer, data + 2,
 848		       min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
 849		ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n",
 850				  min_t(uint16_t, senselen,
 851				  SCSI_SENSE_BUFFERSIZE));
 852	}
 853
 854	if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
 855			   ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
 856		int res_count = be32_to_cpu(rhdr->bi_residual_count);
 857
 858		if (scsi_bidi_cmnd(sc) && res_count > 0 &&
 859				(rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW ||
 860				 res_count <= scsi_in(sc)->length))
 861			scsi_in(sc)->resid = res_count;
 862		else
 863			sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 864	}
 865
 866	if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
 867	                   ISCSI_FLAG_CMD_OVERFLOW)) {
 868		int res_count = be32_to_cpu(rhdr->residual_count);
 869
 870		if (res_count > 0 &&
 871		    (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 872		     res_count <= scsi_bufflen(sc)))
 873			/* write side for bidi or uni-io set_resid */
 874			scsi_set_resid(sc, res_count);
 875		else
 876			sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 877	}
 878out:
 879	ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n",
 880			  sc, sc->result, task->itt);
 881	conn->scsirsp_pdus_cnt++;
 882	iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 883}
 884
 885/**
 886 * iscsi_data_in_rsp - SCSI Data-In Response processing
 887 * @conn: iscsi connection
 888 * @hdr:  iscsi pdu
 889 * @task: scsi command task
 
 
 
 890 **/
 891static void
 892iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 893		  struct iscsi_task *task)
 894{
 895	struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr;
 896	struct scsi_cmnd *sc = task->sc;
 897
 898	if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
 899		return;
 900
 901	iscsi_update_cmdsn(conn->session, (struct iscsi_nopin *)hdr);
 902	sc->result = (DID_OK << 16) | rhdr->cmd_status;
 903	conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
 904	if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
 905	                   ISCSI_FLAG_DATA_OVERFLOW)) {
 906		int res_count = be32_to_cpu(rhdr->residual_count);
 907
 908		if (res_count > 0 &&
 909		    (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
 910		     res_count <= scsi_in(sc)->length))
 911			scsi_in(sc)->resid = res_count;
 912		else
 913			sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 914	}
 915
 916	ISCSI_DBG_SESSION(conn->session, "data in with status done "
 917			  "[sc %p res %d itt 0x%x]\n",
 918			  sc, sc->result, task->itt);
 919	conn->scsirsp_pdus_cnt++;
 920	iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 921}
 922
 923static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
 924{
 925	struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
 
 926
 927	conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
 928	conn->tmfrsp_pdus_cnt++;
 929
 930	if (conn->tmf_state != TMF_QUEUED)
 931		return;
 932
 933	if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
 934		conn->tmf_state = TMF_SUCCESS;
 935	else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
 936		conn->tmf_state = TMF_NOT_FOUND;
 937	else
 938		conn->tmf_state = TMF_FAILED;
 939	wake_up(&conn->ehwait);
 940}
 941
 942static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
 943{
 944        struct iscsi_nopout hdr;
 945	struct iscsi_task *task;
 946
 947	if (!rhdr && conn->ping_task)
 948		return;
 
 
 
 949
 950	memset(&hdr, 0, sizeof(struct iscsi_nopout));
 951	hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
 952	hdr.flags = ISCSI_FLAG_CMD_FINAL;
 953
 954	if (rhdr) {
 955		hdr.lun = rhdr->lun;
 956		hdr.ttt = rhdr->ttt;
 957		hdr.itt = RESERVED_ITT;
 958	} else
 959		hdr.ttt = RESERVED_ITT;
 960
 961	task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
 962	if (!task)
 
 
 963		iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
 964	else if (!rhdr) {
 
 965		/* only track our nops */
 966		conn->ping_task = task;
 967		conn->last_ping = jiffies;
 968	}
 
 
 969}
 970
 
 
 
 
 
 
 
 
 
 
 971static int iscsi_nop_out_rsp(struct iscsi_task *task,
 972			     struct iscsi_nopin *nop, char *data, int datalen)
 973{
 974	struct iscsi_conn *conn = task->conn;
 975	int rc = 0;
 976
 977	if (conn->ping_task != task) {
 978		/*
 979		 * If this is not in response to one of our
 980		 * nops then it must be from userspace.
 981		 */
 982		if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop,
 983				   data, datalen))
 984			rc = ISCSI_ERR_CONN_FAILED;
 985	} else
 986		mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
 987	iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 988	return rc;
 989}
 990
 991static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 992			       char *data, int datalen)
 993{
 994	struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
 995	struct iscsi_hdr rejected_pdu;
 996	int opcode, rc = 0;
 997
 998	conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
 999
1000	if (ntoh24(reject->dlength) > datalen ||
1001	    ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) {
1002		iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected "
1003				  "pdu. Invalid data length (pdu dlength "
1004				  "%u, datalen %d\n", ntoh24(reject->dlength),
1005				  datalen);
1006		return ISCSI_ERR_PROTO;
1007	}
1008	memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
1009	opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK;
1010
1011	switch (reject->reason) {
1012	case ISCSI_REASON_DATA_DIGEST_ERROR:
1013		iscsi_conn_printk(KERN_ERR, conn,
1014				  "pdu (op 0x%x itt 0x%x) rejected "
1015				  "due to DataDigest error.\n",
1016				  rejected_pdu.itt, opcode);
1017		break;
1018	case ISCSI_REASON_IMM_CMD_REJECT:
1019		iscsi_conn_printk(KERN_ERR, conn,
1020				  "pdu (op 0x%x itt 0x%x) rejected. Too many "
1021				  "immediate commands.\n",
1022				  rejected_pdu.itt, opcode);
1023		/*
1024		 * We only send one TMF at a time so if the target could not
1025		 * handle it, then it should get fixed (RFC mandates that
1026		 * a target can handle one immediate TMF per conn).
1027		 *
1028		 * For nops-outs, we could have sent more than one if
1029		 * the target is sending us lots of nop-ins
1030		 */
1031		if (opcode != ISCSI_OP_NOOP_OUT)
1032			return 0;
1033
1034		 if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG))
1035			/*
1036			 * nop-out in response to target's nop-out rejected.
1037			 * Just resend.
1038			 */
 
 
 
1039			iscsi_send_nopout(conn,
1040					  (struct iscsi_nopin*)&rejected_pdu);
1041		else {
 
 
1042			struct iscsi_task *task;
1043			/*
1044			 * Our nop as ping got dropped. We know the target
1045			 * and transport are ok so just clean up
1046			 */
1047			task = iscsi_itt_to_task(conn, rejected_pdu.itt);
1048			if (!task) {
1049				iscsi_conn_printk(KERN_ERR, conn,
1050						 "Invalid pdu reject. Could "
1051						 "not lookup rejected task.\n");
1052				rc = ISCSI_ERR_BAD_ITT;
1053			} else
1054				rc = iscsi_nop_out_rsp(task,
1055					(struct iscsi_nopin*)&rejected_pdu,
1056					NULL, 0);
1057		}
1058		break;
1059	default:
1060		iscsi_conn_printk(KERN_ERR, conn,
1061				  "pdu (op 0x%x itt 0x%x) rejected. Reason "
1062				  "code 0x%x\n", rejected_pdu.itt,
1063				  rejected_pdu.opcode, reject->reason);
1064		break;
1065	}
1066	return rc;
1067}
1068
1069/**
1070 * iscsi_itt_to_task - look up task by itt
1071 * @conn: iscsi connection
1072 * @itt: itt
1073 *
1074 * This should be used for mgmt tasks like login and nops, or if
1075 * the LDD's itt space does not include the session age.
1076 *
1077 * The session lock must be held.
1078 */
1079struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
1080{
1081	struct iscsi_session *session = conn->session;
1082	int i;
1083
1084	if (itt == RESERVED_ITT)
1085		return NULL;
1086
1087	if (session->tt->parse_pdu_itt)
1088		session->tt->parse_pdu_itt(conn, itt, &i, NULL);
1089	else
1090		i = get_itt(itt);
1091	if (i >= session->cmds_max)
1092		return NULL;
1093
1094	return session->cmds[i];
1095}
1096EXPORT_SYMBOL_GPL(iscsi_itt_to_task);
1097
1098/**
1099 * __iscsi_complete_pdu - complete pdu
1100 * @conn: iscsi conn
1101 * @hdr: iscsi header
1102 * @data: data buffer
1103 * @datalen: len of data buffer
1104 *
1105 * Completes pdu processing by freeing any resources allocated at
1106 * queuecommand or send generic. session lock must be held and verify
1107 * itt must have been called.
1108 */
1109int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1110			 char *data, int datalen)
1111{
1112	struct iscsi_session *session = conn->session;
1113	int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
1114	struct iscsi_task *task;
1115	uint32_t itt;
1116
1117	conn->last_recv = jiffies;
1118	rc = iscsi_verify_itt(conn, hdr->itt);
1119	if (rc)
1120		return rc;
1121
1122	if (hdr->itt != RESERVED_ITT)
1123		itt = get_itt(hdr->itt);
1124	else
1125		itt = ~0U;
1126
1127	ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n",
1128			  opcode, conn->id, itt, datalen);
1129
1130	if (itt == ~0U) {
1131		iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1132
1133		switch(opcode) {
1134		case ISCSI_OP_NOOP_IN:
1135			if (datalen) {
1136				rc = ISCSI_ERR_PROTO;
1137				break;
1138			}
1139
1140			if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
1141				break;
1142
 
 
 
1143			iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
 
 
1144			break;
1145		case ISCSI_OP_REJECT:
1146			rc = iscsi_handle_reject(conn, hdr, data, datalen);
1147			break;
1148		case ISCSI_OP_ASYNC_EVENT:
1149			conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1150			if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1151				rc = ISCSI_ERR_CONN_FAILED;
1152			break;
1153		default:
1154			rc = ISCSI_ERR_BAD_OPCODE;
1155			break;
1156		}
1157		goto out;
1158	}
1159
1160	switch(opcode) {
1161	case ISCSI_OP_SCSI_CMD_RSP:
1162	case ISCSI_OP_SCSI_DATA_IN:
1163		task = iscsi_itt_to_ctask(conn, hdr->itt);
1164		if (!task)
1165			return ISCSI_ERR_BAD_ITT;
1166		task->last_xfer = jiffies;
1167		break;
1168	case ISCSI_OP_R2T:
1169		/*
1170		 * LLD handles R2Ts if they need to.
1171		 */
1172		return 0;
1173	case ISCSI_OP_LOGOUT_RSP:
1174	case ISCSI_OP_LOGIN_RSP:
1175	case ISCSI_OP_TEXT_RSP:
1176	case ISCSI_OP_SCSI_TMFUNC_RSP:
1177	case ISCSI_OP_NOOP_IN:
1178		task = iscsi_itt_to_task(conn, hdr->itt);
1179		if (!task)
1180			return ISCSI_ERR_BAD_ITT;
1181		break;
1182	default:
1183		return ISCSI_ERR_BAD_OPCODE;
1184	}
1185
1186	switch(opcode) {
1187	case ISCSI_OP_SCSI_CMD_RSP:
1188		iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
1189		break;
1190	case ISCSI_OP_SCSI_DATA_IN:
1191		iscsi_data_in_rsp(conn, hdr, task);
1192		break;
1193	case ISCSI_OP_LOGOUT_RSP:
1194		iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1195		if (datalen) {
1196			rc = ISCSI_ERR_PROTO;
1197			break;
1198		}
1199		conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1200		goto recv_pdu;
1201	case ISCSI_OP_LOGIN_RSP:
1202	case ISCSI_OP_TEXT_RSP:
1203		iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1204		/*
1205		 * login related PDU's exp_statsn is handled in
1206		 * userspace
1207		 */
1208		goto recv_pdu;
1209	case ISCSI_OP_SCSI_TMFUNC_RSP:
1210		iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1211		if (datalen) {
1212			rc = ISCSI_ERR_PROTO;
1213			break;
1214		}
1215
1216		iscsi_tmf_rsp(conn, hdr);
1217		iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1218		break;
1219	case ISCSI_OP_NOOP_IN:
1220		iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1221		if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
1222			rc = ISCSI_ERR_PROTO;
1223			break;
1224		}
1225		conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1226
1227		rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr,
1228				       data, datalen);
1229		break;
1230	default:
1231		rc = ISCSI_ERR_BAD_OPCODE;
1232		break;
1233	}
1234
1235out:
1236	return rc;
1237recv_pdu:
1238	if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1239		rc = ISCSI_ERR_CONN_FAILED;
1240	iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1241	return rc;
1242}
1243EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
1244
1245int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1246		       char *data, int datalen)
1247{
1248	int rc;
1249
1250	spin_lock(&conn->session->lock);
1251	rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
1252	spin_unlock(&conn->session->lock);
1253	return rc;
1254}
1255EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
1256
1257int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
1258{
1259	struct iscsi_session *session = conn->session;
1260	int age = 0, i = 0;
1261
1262	if (itt == RESERVED_ITT)
1263		return 0;
1264
1265	if (session->tt->parse_pdu_itt)
1266		session->tt->parse_pdu_itt(conn, itt, &i, &age);
1267	else {
1268		i = get_itt(itt);
1269		age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK;
1270	}
1271
1272	if (age != session->age) {
1273		iscsi_conn_printk(KERN_ERR, conn,
1274				  "received itt %x expected session age (%x)\n",
1275				  (__force u32)itt, session->age);
1276		return ISCSI_ERR_BAD_ITT;
1277	}
1278
1279	if (i >= session->cmds_max) {
1280		iscsi_conn_printk(KERN_ERR, conn,
1281				  "received invalid itt index %u (max cmds "
1282				   "%u.\n", i, session->cmds_max);
1283		return ISCSI_ERR_BAD_ITT;
1284	}
1285	return 0;
1286}
1287EXPORT_SYMBOL_GPL(iscsi_verify_itt);
1288
1289/**
1290 * iscsi_itt_to_ctask - look up ctask by itt
1291 * @conn: iscsi connection
1292 * @itt: itt
1293 *
1294 * This should be used for cmd tasks.
1295 *
1296 * The session lock must be held.
1297 */
1298struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
1299{
1300	struct iscsi_task *task;
1301
1302	if (iscsi_verify_itt(conn, itt))
1303		return NULL;
1304
1305	task = iscsi_itt_to_task(conn, itt);
1306	if (!task || !task->sc)
1307		return NULL;
1308
1309	if (task->sc->SCp.phase != conn->session->age) {
1310		iscsi_session_printk(KERN_ERR, conn->session,
1311				  "task's session age %d, expected %d\n",
1312				  task->sc->SCp.phase, conn->session->age);
1313		return NULL;
1314	}
1315
1316	return task;
1317}
1318EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
1319
1320void iscsi_session_failure(struct iscsi_session *session,
1321			   enum iscsi_err err)
1322{
1323	struct iscsi_conn *conn;
1324	struct device *dev;
1325
1326	spin_lock_bh(&session->lock);
1327	conn = session->leadconn;
1328	if (session->state == ISCSI_STATE_TERMINATE || !conn) {
1329		spin_unlock_bh(&session->lock);
1330		return;
1331	}
1332
1333	dev = get_device(&conn->cls_conn->dev);
1334	spin_unlock_bh(&session->lock);
1335	if (!dev)
1336	        return;
1337	/*
1338	 * if the host is being removed bypass the connection
1339	 * recovery initialization because we are going to kill
1340	 * the session.
1341	 */
1342	if (err == ISCSI_ERR_INVALID_HOST)
1343		iscsi_conn_error_event(conn->cls_conn, err);
1344	else
1345		iscsi_conn_failure(conn, err);
1346	put_device(dev);
1347}
1348EXPORT_SYMBOL_GPL(iscsi_session_failure);
1349
1350void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
1351{
1352	struct iscsi_session *session = conn->session;
1353
1354	spin_lock_bh(&session->lock);
1355	if (session->state == ISCSI_STATE_FAILED) {
1356		spin_unlock_bh(&session->lock);
1357		return;
1358	}
1359
1360	if (conn->stop_stage == 0)
1361		session->state = ISCSI_STATE_FAILED;
1362	spin_unlock_bh(&session->lock);
1363
1364	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1365	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1366	iscsi_conn_error_event(conn->cls_conn, err);
 
 
 
 
 
 
 
 
 
 
 
 
 
1367}
1368EXPORT_SYMBOL_GPL(iscsi_conn_failure);
1369
1370static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
1371{
1372	struct iscsi_session *session = conn->session;
1373
1374	/*
1375	 * Check for iSCSI window and take care of CmdSN wrap-around
1376	 */
1377	if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
1378		ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn "
1379				  "%u MaxCmdSN %u CmdSN %u/%u\n",
1380				  session->exp_cmdsn, session->max_cmdsn,
1381				  session->cmdsn, session->queued_cmdsn);
1382		return -ENOSPC;
1383	}
1384	return 0;
1385}
1386
1387static int iscsi_xmit_task(struct iscsi_conn *conn)
 
1388{
1389	struct iscsi_task *task = conn->task;
1390	int rc;
1391
1392	if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1393		return -ENODATA;
 
 
1394
1395	__iscsi_get_task(task);
1396	spin_unlock_bh(&conn->session->lock);
1397	rc = conn->session->tt->xmit_task(task);
1398	spin_lock_bh(&conn->session->lock);
1399	if (!rc) {
1400		/* done with this task */
1401		task->last_xfer = jiffies;
1402		conn->task = NULL;
1403	}
 
 
 
 
 
 
 
 
 
 
 
1404	__iscsi_put_task(task);
 
1405	return rc;
1406}
1407
1408/**
1409 * iscsi_requeue_task - requeue task to run from session workqueue
1410 * @task: task to requeue
1411 *
1412 * LLDs that need to run a task from the session workqueue should call
1413 * this. The session lock must be held. This should only be called
1414 * by software drivers.
1415 */
1416void iscsi_requeue_task(struct iscsi_task *task)
1417{
1418	struct iscsi_conn *conn = task->conn;
1419
1420	/*
1421	 * this may be on the requeue list already if the xmit_task callout
1422	 * is handling the r2ts while we are adding new ones
1423	 */
1424	if (list_empty(&task->running))
 
1425		list_add_tail(&task->running, &conn->requeue);
 
 
 
 
 
 
 
1426	iscsi_conn_queue_work(conn);
 
1427}
1428EXPORT_SYMBOL_GPL(iscsi_requeue_task);
1429
1430/**
1431 * iscsi_data_xmit - xmit any command into the scheduled connection
1432 * @conn: iscsi connection
1433 *
1434 * Notes:
1435 *	The function can return -EAGAIN in which case the caller must
1436 *	re-schedule it again later or recover. '0' return code means
1437 *	successful xmit.
1438 **/
1439static int iscsi_data_xmit(struct iscsi_conn *conn)
1440{
1441	struct iscsi_task *task;
1442	int rc = 0;
1443
1444	spin_lock_bh(&conn->session->lock);
1445	if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1446		ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n");
1447		spin_unlock_bh(&conn->session->lock);
1448		return -ENODATA;
1449	}
1450
1451	if (conn->task) {
1452		rc = iscsi_xmit_task(conn);
1453	        if (rc)
1454		        goto done;
1455	}
1456
1457	/*
1458	 * process mgmt pdus like nops before commands since we should
1459	 * only have one nop-out as a ping from us and targets should not
1460	 * overflow us with nop-ins
1461	 */
1462check_mgmt:
1463	while (!list_empty(&conn->mgmtqueue)) {
1464		conn->task = list_entry(conn->mgmtqueue.next,
1465					 struct iscsi_task, running);
1466		list_del_init(&conn->task->running);
1467		if (iscsi_prep_mgmt_task(conn, conn->task)) {
1468			__iscsi_put_task(conn->task);
1469			conn->task = NULL;
 
 
1470			continue;
1471		}
1472		rc = iscsi_xmit_task(conn);
1473		if (rc)
1474			goto done;
1475	}
1476
1477	/* process pending command queue */
1478	while (!list_empty(&conn->cmdqueue)) {
1479		conn->task = list_entry(conn->cmdqueue.next, struct iscsi_task,
1480					running);
1481		list_del_init(&conn->task->running);
1482		if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1483			fail_scsi_task(conn->task, DID_IMM_RETRY);
1484			continue;
1485		}
1486		rc = iscsi_prep_scsi_cmd_pdu(conn->task);
1487		if (rc) {
1488			if (rc == -ENOMEM || rc == -EACCES) {
1489				list_add_tail(&conn->task->running,
1490					      &conn->cmdqueue);
1491				conn->task = NULL;
1492				goto done;
1493			} else
1494				fail_scsi_task(conn->task, DID_ABORT);
1495			continue;
1496		}
1497		rc = iscsi_xmit_task(conn);
1498		if (rc)
1499			goto done;
1500		/*
1501		 * we could continuously get new task requests so
1502		 * we need to check the mgmt queue for nops that need to
1503		 * be sent to aviod starvation
1504		 */
1505		if (!list_empty(&conn->mgmtqueue))
1506			goto check_mgmt;
1507	}
1508
1509	while (!list_empty(&conn->requeue)) {
1510		/*
1511		 * we always do fastlogout - conn stop code will clean up.
1512		 */
1513		if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1514			break;
1515
1516		task = list_entry(conn->requeue.next, struct iscsi_task,
1517				  running);
 
1518		if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT))
1519			break;
1520
1521		conn->task = task;
1522		list_del_init(&conn->task->running);
1523		conn->task->state = ISCSI_TASK_RUNNING;
1524		rc = iscsi_xmit_task(conn);
1525		if (rc)
1526			goto done;
1527		if (!list_empty(&conn->mgmtqueue))
1528			goto check_mgmt;
1529	}
1530	spin_unlock_bh(&conn->session->lock);
1531	return -ENODATA;
1532
1533done:
1534	spin_unlock_bh(&conn->session->lock);
1535	return rc;
1536}
1537
1538static void iscsi_xmitworker(struct work_struct *work)
1539{
1540	struct iscsi_conn *conn =
1541		container_of(work, struct iscsi_conn, xmitwork);
1542	int rc;
1543	/*
1544	 * serialize Xmit worker on a per-connection basis.
1545	 */
1546	do {
1547		rc = iscsi_data_xmit(conn);
1548	} while (rc >= 0 || rc == -EAGAIN);
1549}
1550
1551static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
1552						  struct scsi_cmnd *sc)
1553{
1554	struct iscsi_task *task;
1555
1556	if (!kfifo_out(&conn->session->cmdpool.queue,
1557			 (void *) &task, sizeof(void *)))
1558		return NULL;
1559
1560	sc->SCp.phase = conn->session->age;
1561	sc->SCp.ptr = (char *) task;
1562
1563	atomic_set(&task->refcount, 1);
1564	task->state = ISCSI_TASK_PENDING;
1565	task->conn = conn;
1566	task->sc = sc;
1567	task->have_checked_conn = false;
1568	task->last_timeout = jiffies;
1569	task->last_xfer = jiffies;
 
1570	INIT_LIST_HEAD(&task->running);
1571	return task;
1572}
1573
1574enum {
1575	FAILURE_BAD_HOST = 1,
1576	FAILURE_SESSION_FAILED,
1577	FAILURE_SESSION_FREED,
1578	FAILURE_WINDOW_CLOSED,
1579	FAILURE_OOM,
1580	FAILURE_SESSION_TERMINATE,
1581	FAILURE_SESSION_IN_RECOVERY,
1582	FAILURE_SESSION_RECOVERY_TIMEOUT,
1583	FAILURE_SESSION_LOGGING_OUT,
1584	FAILURE_SESSION_NOT_READY,
1585};
1586
1587int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
1588{
1589	struct iscsi_cls_session *cls_session;
1590	struct iscsi_host *ihost;
1591	int reason = 0;
1592	struct iscsi_session *session;
1593	struct iscsi_conn *conn;
1594	struct iscsi_task *task = NULL;
1595
1596	sc->result = 0;
1597	sc->SCp.ptr = NULL;
1598
1599	ihost = shost_priv(host);
1600
1601	cls_session = starget_to_session(scsi_target(sc->device));
1602	session = cls_session->dd_data;
1603	spin_lock_bh(&session->lock);
1604
1605	reason = iscsi_session_chkready(cls_session);
1606	if (reason) {
1607		sc->result = reason;
1608		goto fault;
1609	}
1610
1611	if (session->state != ISCSI_STATE_LOGGED_IN) {
1612		/*
1613		 * to handle the race between when we set the recovery state
1614		 * and block the session we requeue here (commands could
1615		 * be entering our queuecommand while a block is starting
1616		 * up because the block code is not locked)
1617		 */
1618		switch (session->state) {
1619		case ISCSI_STATE_FAILED:
 
 
 
 
 
 
 
 
 
 
1620		case ISCSI_STATE_IN_RECOVERY:
1621			reason = FAILURE_SESSION_IN_RECOVERY;
1622			sc->result = DID_IMM_RETRY << 16;
1623			break;
1624		case ISCSI_STATE_LOGGING_OUT:
1625			reason = FAILURE_SESSION_LOGGING_OUT;
1626			sc->result = DID_IMM_RETRY << 16;
1627			break;
1628		case ISCSI_STATE_RECOVERY_FAILED:
1629			reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1630			sc->result = DID_TRANSPORT_FAILFAST << 16;
1631			break;
1632		case ISCSI_STATE_TERMINATE:
1633			reason = FAILURE_SESSION_TERMINATE;
1634			sc->result = DID_NO_CONNECT << 16;
1635			break;
1636		default:
1637			reason = FAILURE_SESSION_FREED;
1638			sc->result = DID_NO_CONNECT << 16;
1639		}
1640		goto fault;
1641	}
1642
1643	conn = session->leadconn;
1644	if (!conn) {
1645		reason = FAILURE_SESSION_FREED;
1646		sc->result = DID_NO_CONNECT << 16;
1647		goto fault;
1648	}
1649
1650	if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1651		reason = FAILURE_SESSION_IN_RECOVERY;
1652		sc->result = DID_REQUEUE;
1653		goto fault;
1654	}
1655
1656	if (iscsi_check_cmdsn_window_closed(conn)) {
1657		reason = FAILURE_WINDOW_CLOSED;
1658		goto reject;
1659	}
1660
1661	task = iscsi_alloc_task(conn, sc);
1662	if (!task) {
1663		reason = FAILURE_OOM;
1664		goto reject;
1665	}
1666
1667	if (!ihost->workq) {
1668		reason = iscsi_prep_scsi_cmd_pdu(task);
1669		if (reason) {
1670			if (reason == -ENOMEM ||  reason == -EACCES) {
1671				reason = FAILURE_OOM;
1672				goto prepd_reject;
1673			} else {
1674				sc->result = DID_ABORT << 16;
1675				goto prepd_fault;
1676			}
1677		}
1678		if (session->tt->xmit_task(task)) {
1679			session->cmdsn--;
1680			reason = FAILURE_SESSION_NOT_READY;
1681			goto prepd_reject;
1682		}
1683	} else {
1684		list_add_tail(&task->running, &conn->cmdqueue);
1685		iscsi_conn_queue_work(conn);
1686	}
1687
1688	session->queued_cmdsn++;
1689	spin_unlock_bh(&session->lock);
1690	return 0;
1691
1692prepd_reject:
 
1693	iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
 
1694reject:
1695	spin_unlock_bh(&session->lock);
1696	ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
1697			  sc->cmnd[0], reason);
1698	return SCSI_MLQUEUE_TARGET_BUSY;
1699
1700prepd_fault:
 
1701	iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
 
1702fault:
1703	spin_unlock_bh(&session->lock);
1704	ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
1705			  sc->cmnd[0], reason);
1706	if (!scsi_bidi_cmnd(sc))
1707		scsi_set_resid(sc, scsi_bufflen(sc));
1708	else {
1709		scsi_out(sc)->resid = scsi_out(sc)->length;
1710		scsi_in(sc)->resid = scsi_in(sc)->length;
1711	}
1712	sc->scsi_done(sc);
1713	return 0;
1714}
1715EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1716
1717int iscsi_change_queue_depth(struct scsi_device *sdev, int depth, int reason)
1718{
1719	switch (reason) {
1720	case SCSI_QDEPTH_DEFAULT:
1721		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1722		break;
1723	case SCSI_QDEPTH_QFULL:
1724		scsi_track_queue_full(sdev, depth);
1725		break;
1726	case SCSI_QDEPTH_RAMP_UP:
1727		scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
1728		break;
1729	default:
1730		return -EOPNOTSUPP;
1731	}
1732	return sdev->queue_depth;
1733}
1734EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
1735
1736int iscsi_target_alloc(struct scsi_target *starget)
1737{
1738	struct iscsi_cls_session *cls_session = starget_to_session(starget);
1739	struct iscsi_session *session = cls_session->dd_data;
1740
1741	starget->can_queue = session->scsi_cmds_max;
1742	return 0;
1743}
1744EXPORT_SYMBOL_GPL(iscsi_target_alloc);
1745
1746static void iscsi_tmf_timedout(unsigned long data)
1747{
1748	struct iscsi_conn *conn = (struct iscsi_conn *)data;
1749	struct iscsi_session *session = conn->session;
1750
1751	spin_lock(&session->lock);
1752	if (conn->tmf_state == TMF_QUEUED) {
1753		conn->tmf_state = TMF_TIMEDOUT;
1754		ISCSI_DBG_EH(session, "tmf timedout\n");
1755		/* unblock eh_abort() */
1756		wake_up(&conn->ehwait);
1757	}
1758	spin_unlock(&session->lock);
1759}
1760
1761static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1762				   struct iscsi_tm *hdr, int age,
1763				   int timeout)
 
1764{
1765	struct iscsi_session *session = conn->session;
1766	struct iscsi_task *task;
1767
1768	task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1769				      NULL, 0);
1770	if (!task) {
1771		spin_unlock_bh(&session->lock);
1772		iscsi_conn_printk(KERN_ERR, conn, "Could not send TMF.\n");
1773		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1774		spin_lock_bh(&session->lock);
1775		return -EPERM;
1776	}
1777	conn->tmfcmd_pdus_cnt++;
1778	conn->tmf_timer.expires = timeout * HZ + jiffies;
1779	conn->tmf_timer.function = iscsi_tmf_timedout;
1780	conn->tmf_timer.data = (unsigned long)conn;
1781	add_timer(&conn->tmf_timer);
1782	ISCSI_DBG_EH(session, "tmf set timeout\n");
1783
1784	spin_unlock_bh(&session->lock);
1785	mutex_unlock(&session->eh_mutex);
1786
1787	/*
1788	 * block eh thread until:
1789	 *
1790	 * 1) tmf response
1791	 * 2) tmf timeout
1792	 * 3) session is terminated or restarted or userspace has
1793	 * given up on recovery
1794	 */
1795	wait_event_interruptible(conn->ehwait, age != session->age ||
1796				 session->state != ISCSI_STATE_LOGGED_IN ||
1797				 conn->tmf_state != TMF_QUEUED);
1798	if (signal_pending(current))
1799		flush_signals(current);
1800	del_timer_sync(&conn->tmf_timer);
1801
1802	mutex_lock(&session->eh_mutex);
1803	spin_lock_bh(&session->lock);
1804	/* if the session drops it will clean up the task */
1805	if (age != session->age ||
1806	    session->state != ISCSI_STATE_LOGGED_IN)
1807		return -ENOTCONN;
1808	return 0;
1809}
1810
1811/*
1812 * Fail commands. session lock held and recv side suspended and xmit
1813 * thread flushed
1814 */
1815static void fail_scsi_tasks(struct iscsi_conn *conn, unsigned lun,
1816			    int error)
1817{
 
1818	struct iscsi_task *task;
1819	int i;
1820
1821	for (i = 0; i < conn->session->cmds_max; i++) {
1822		task = conn->session->cmds[i];
 
1823		if (!task->sc || task->state == ISCSI_TASK_FREE)
1824			continue;
1825
1826		if (lun != -1 && lun != task->sc->device->lun)
1827			continue;
1828
1829		ISCSI_DBG_SESSION(conn->session,
 
 
 
1830				  "failing sc %p itt 0x%x state %d\n",
1831				  task->sc, task->itt, task->state);
1832		fail_scsi_task(task, error);
 
 
 
 
 
 
1833	}
 
 
1834}
1835
1836/**
1837 * iscsi_suspend_queue - suspend iscsi_queuecommand
1838 * @conn: iscsi conn to stop queueing IO on
1839 *
1840 * This grabs the session lock to make sure no one is in
1841 * xmit_task/queuecommand, and then sets suspend to prevent
1842 * new commands from being queued. This only needs to be called
1843 * by offload drivers that need to sync a path like ep disconnect
1844 * with the iscsi_queuecommand/xmit_task. To start IO again libiscsi
1845 * will call iscsi_start_tx and iscsi_unblock_session when in FFP.
1846 */
1847void iscsi_suspend_queue(struct iscsi_conn *conn)
1848{
1849	spin_lock_bh(&conn->session->lock);
1850	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1851	spin_unlock_bh(&conn->session->lock);
1852}
1853EXPORT_SYMBOL_GPL(iscsi_suspend_queue);
1854
1855/**
1856 * iscsi_suspend_tx - suspend iscsi_data_xmit
1857 * @conn: iscsi conn tp stop processing IO on.
1858 *
1859 * This function sets the suspend bit to prevent iscsi_data_xmit
1860 * from sending new IO, and if work is queued on the xmit thread
1861 * it will wait for it to be completed.
1862 */
1863void iscsi_suspend_tx(struct iscsi_conn *conn)
1864{
1865	struct Scsi_Host *shost = conn->session->host;
1866	struct iscsi_host *ihost = shost_priv(shost);
1867
1868	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1869	if (ihost->workq)
1870		flush_workqueue(ihost->workq);
1871}
1872EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
1873
1874static void iscsi_start_tx(struct iscsi_conn *conn)
1875{
1876	clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1877	iscsi_conn_queue_work(conn);
1878}
1879
1880/*
1881 * We want to make sure a ping is in flight. It has timed out.
1882 * And we are not busy processing a pdu that is making
1883 * progress but got started before the ping and is taking a while
1884 * to complete so the ping is just stuck behind it in a queue.
1885 */
1886static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
1887{
1888	if (conn->ping_task &&
1889	    time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1890			   (conn->ping_timeout * HZ), jiffies))
1891		return 1;
1892	else
1893		return 0;
1894}
1895
1896static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
1897{
1898	enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
1899	struct iscsi_task *task = NULL, *running_task;
1900	struct iscsi_cls_session *cls_session;
1901	struct iscsi_session *session;
1902	struct iscsi_conn *conn;
1903	int i;
1904
1905	cls_session = starget_to_session(scsi_target(sc->device));
1906	session = cls_session->dd_data;
1907
1908	ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc);
1909
1910	spin_lock(&session->lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1911	if (session->state != ISCSI_STATE_LOGGED_IN) {
1912		/*
 
 
 
 
 
 
 
 
 
 
 
 
 
1913		 * We are probably in the middle of iscsi recovery so let
1914		 * that complete and handle the error.
1915		 */
1916		rc = BLK_EH_RESET_TIMER;
1917		goto done;
1918	}
1919
1920	conn = session->leadconn;
1921	if (!conn) {
1922		/* In the middle of shuting down */
1923		rc = BLK_EH_RESET_TIMER;
1924		goto done;
1925	}
1926
1927	task = (struct iscsi_task *)sc->SCp.ptr;
1928	if (!task) {
1929		/*
1930		 * Raced with completion. Just reset timer, and let it
1931		 * complete normally
1932		 */
1933		rc = BLK_EH_RESET_TIMER;
1934		goto done;
1935	}
1936
1937	/*
1938	 * If we have sent (at least queued to the network layer) a pdu or
1939	 * recvd one for the task since the last timeout ask for
1940	 * more time. If on the next timeout we have not made progress
1941	 * we can check if it is the task or connection when we send the
1942	 * nop as a ping.
1943	 */
1944	if (time_after(task->last_xfer, task->last_timeout)) {
1945		ISCSI_DBG_EH(session, "Command making progress. Asking "
1946			     "scsi-ml for more time to complete. "
1947			     "Last data xfer at %lu. Last timeout was at "
1948			     "%lu\n.", task->last_xfer, task->last_timeout);
1949		task->have_checked_conn = false;
1950		rc = BLK_EH_RESET_TIMER;
1951		goto done;
1952	}
1953
1954	if (!conn->recv_timeout && !conn->ping_timeout)
1955		goto done;
1956	/*
1957	 * if the ping timedout then we are in the middle of cleaning up
1958	 * and can let the iscsi eh handle it
1959	 */
1960	if (iscsi_has_ping_timed_out(conn)) {
1961		rc = BLK_EH_RESET_TIMER;
1962		goto done;
1963	}
1964
 
1965	for (i = 0; i < conn->session->cmds_max; i++) {
1966		running_task = conn->session->cmds[i];
1967		if (!running_task->sc || running_task == task ||
1968		     running_task->state != ISCSI_TASK_RUNNING)
1969			continue;
1970
1971		/*
1972		 * Only check if cmds started before this one have made
1973		 * progress, or this could never fail
1974		 */
1975		if (time_after(running_task->sc->jiffies_at_alloc,
1976			       task->sc->jiffies_at_alloc))
1977			continue;
1978
1979		if (time_after(running_task->last_xfer, task->last_timeout)) {
1980			/*
1981			 * This task has not made progress, but a task
1982			 * started before us has transferred data since
1983			 * we started/last-checked. We could be queueing
1984			 * too many tasks or the LU is bad.
1985			 *
1986			 * If the device is bad the cmds ahead of us on
1987			 * other devs will complete, and this loop will
1988			 * eventually fail starting the scsi eh.
1989			 */
1990			ISCSI_DBG_EH(session, "Command has not made progress "
1991				     "but commands ahead of it have. "
1992				     "Asking scsi-ml for more time to "
1993				     "complete. Our last xfer vs running task "
1994				     "last xfer %lu/%lu. Last check %lu.\n",
1995				     task->last_xfer, running_task->last_xfer,
1996				     task->last_timeout);
 
1997			rc = BLK_EH_RESET_TIMER;
1998			goto done;
1999		}
2000	}
 
2001
2002	/* Assumes nop timeout is shorter than scsi cmd timeout */
2003	if (task->have_checked_conn)
2004		goto done;
2005
2006	/*
2007	 * Checking the transport already or nop from a cmd timeout still
2008	 * running
2009	 */
2010	if (conn->ping_task) {
2011		task->have_checked_conn = true;
2012		rc = BLK_EH_RESET_TIMER;
2013		goto done;
2014	}
2015
2016	/* Make sure there is a transport check done */
2017	iscsi_send_nopout(conn, NULL);
2018	task->have_checked_conn = true;
2019	rc = BLK_EH_RESET_TIMER;
2020
2021done:
2022	if (task)
 
 
2023		task->last_timeout = jiffies;
2024	spin_unlock(&session->lock);
 
2025	ISCSI_DBG_EH(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
2026		     "timer reset" : "nh");
2027	return rc;
2028}
 
2029
2030static void iscsi_check_transport_timeouts(unsigned long data)
2031{
2032	struct iscsi_conn *conn = (struct iscsi_conn *)data;
2033	struct iscsi_session *session = conn->session;
2034	unsigned long recv_timeout, next_timeout = 0, last_recv;
2035
2036	spin_lock(&session->lock);
2037	if (session->state != ISCSI_STATE_LOGGED_IN)
2038		goto done;
2039
2040	recv_timeout = conn->recv_timeout;
2041	if (!recv_timeout)
2042		goto done;
2043
2044	recv_timeout *= HZ;
2045	last_recv = conn->last_recv;
2046
2047	if (iscsi_has_ping_timed_out(conn)) {
2048		iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
2049				  "expired, recv timeout %d, last rx %lu, "
2050				  "last ping %lu, now %lu\n",
2051				  conn->ping_timeout, conn->recv_timeout,
2052				  last_recv, conn->last_ping, jiffies);
2053		spin_unlock(&session->lock);
2054		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
2055		return;
2056	}
2057
2058	if (time_before_eq(last_recv + recv_timeout, jiffies)) {
2059		/* send a ping to try to provoke some traffic */
2060		ISCSI_DBG_CONN(conn, "Sending nopout as ping\n");
2061		iscsi_send_nopout(conn, NULL);
2062		next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
 
 
2063	} else
2064		next_timeout = last_recv + recv_timeout;
2065
2066	ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout);
2067	mod_timer(&conn->transport_timer, next_timeout);
2068done:
2069	spin_unlock(&session->lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2070}
 
2071
2072static void iscsi_prep_abort_task_pdu(struct iscsi_task *task,
2073				      struct iscsi_tm *hdr)
2074{
2075	memset(hdr, 0, sizeof(*hdr));
2076	hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2077	hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
2078	hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2079	hdr->lun = task->lun;
2080	hdr->rtt = task->hdr_itt;
2081	hdr->refcmdsn = task->cmdsn;
2082}
2083
2084int iscsi_eh_abort(struct scsi_cmnd *sc)
2085{
2086	struct iscsi_cls_session *cls_session;
2087	struct iscsi_session *session;
2088	struct iscsi_conn *conn;
2089	struct iscsi_task *task;
2090	struct iscsi_tm *hdr;
2091	int rc, age;
2092
2093	cls_session = starget_to_session(scsi_target(sc->device));
2094	session = cls_session->dd_data;
2095
2096	ISCSI_DBG_EH(session, "aborting sc %p\n", sc);
2097
2098	mutex_lock(&session->eh_mutex);
2099	spin_lock_bh(&session->lock);
2100	/*
2101	 * if session was ISCSI_STATE_IN_RECOVERY then we may not have
2102	 * got the command.
2103	 */
2104	if (!sc->SCp.ptr) {
2105		ISCSI_DBG_EH(session, "sc never reached iscsi layer or "
2106				      "it completed.\n");
2107		spin_unlock_bh(&session->lock);
2108		mutex_unlock(&session->eh_mutex);
2109		return SUCCESS;
2110	}
2111
2112	/*
2113	 * If we are not logged in or we have started a new session
2114	 * then let the host reset code handle this
2115	 */
2116	if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
2117	    sc->SCp.phase != session->age) {
2118		spin_unlock_bh(&session->lock);
2119		mutex_unlock(&session->eh_mutex);
2120		ISCSI_DBG_EH(session, "failing abort due to dropped "
2121				  "session.\n");
2122		return FAILED;
2123	}
2124
 
 
 
 
 
 
 
 
 
 
 
 
2125	conn = session->leadconn;
 
2126	conn->eh_abort_cnt++;
2127	age = session->age;
2128
2129	task = (struct iscsi_task *)sc->SCp.ptr;
2130	ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n",
2131		     sc, task->itt);
2132
2133	/* task completed before time out */
2134	if (!task->sc) {
2135		ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
2136		goto success;
2137	}
2138
2139	if (task->state == ISCSI_TASK_PENDING) {
2140		fail_scsi_task(task, DID_ABORT);
2141		goto success;
2142	}
2143
2144	/* only have one tmf outstanding at a time */
2145	if (conn->tmf_state != TMF_INITIAL)
2146		goto failed;
2147	conn->tmf_state = TMF_QUEUED;
2148
2149	hdr = &conn->tmhdr;
2150	iscsi_prep_abort_task_pdu(task, hdr);
2151
2152	if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
2153		rc = FAILED;
2154		goto failed;
2155	}
2156
2157	switch (conn->tmf_state) {
2158	case TMF_SUCCESS:
2159		spin_unlock_bh(&session->lock);
2160		/*
2161		 * stop tx side incase the target had sent a abort rsp but
2162		 * the initiator was still writing out data.
2163		 */
2164		iscsi_suspend_tx(conn);
2165		/*
2166		 * we do not stop the recv side because targets have been
2167		 * good and have never sent us a successful tmf response
2168		 * then sent more data for the cmd.
2169		 */
2170		spin_lock_bh(&session->lock);
2171		fail_scsi_task(task, DID_ABORT);
2172		conn->tmf_state = TMF_INITIAL;
2173		memset(hdr, 0, sizeof(*hdr));
2174		spin_unlock_bh(&session->lock);
2175		iscsi_start_tx(conn);
2176		goto success_unlocked;
2177	case TMF_TIMEDOUT:
2178		spin_unlock_bh(&session->lock);
 
2179		iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2180		goto failed_unlocked;
2181	case TMF_NOT_FOUND:
2182		if (!sc->SCp.ptr) {
2183			conn->tmf_state = TMF_INITIAL;
2184			memset(hdr, 0, sizeof(*hdr));
2185			/* task completed before tmf abort response */
2186			ISCSI_DBG_EH(session, "sc completed while abort	in "
2187					      "progress\n");
2188			goto success;
2189		}
2190		/* fall through */
2191	default:
2192		conn->tmf_state = TMF_INITIAL;
2193		goto failed;
2194	}
2195
2196success:
2197	spin_unlock_bh(&session->lock);
2198success_unlocked:
2199	ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n",
2200		     sc, task->itt);
 
 
2201	mutex_unlock(&session->eh_mutex);
2202	return SUCCESS;
2203
2204failed:
2205	spin_unlock_bh(&session->lock);
2206failed_unlocked:
2207	ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
2208		     task ? task->itt : 0);
 
 
 
 
 
 
 
 
 
2209	mutex_unlock(&session->eh_mutex);
2210	return FAILED;
2211}
2212EXPORT_SYMBOL_GPL(iscsi_eh_abort);
2213
2214static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2215{
2216	memset(hdr, 0, sizeof(*hdr));
2217	hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2218	hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2219	hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2220	int_to_scsilun(sc->device->lun, &hdr->lun);
2221	hdr->rtt = RESERVED_ITT;
2222}
2223
2224int iscsi_eh_device_reset(struct scsi_cmnd *sc)
2225{
2226	struct iscsi_cls_session *cls_session;
2227	struct iscsi_session *session;
2228	struct iscsi_conn *conn;
2229	struct iscsi_tm *hdr;
2230	int rc = FAILED;
2231
2232	cls_session = starget_to_session(scsi_target(sc->device));
2233	session = cls_session->dd_data;
2234
2235	ISCSI_DBG_EH(session, "LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
 
2236
2237	mutex_lock(&session->eh_mutex);
2238	spin_lock_bh(&session->lock);
2239	/*
2240	 * Just check if we are not logged in. We cannot check for
2241	 * the phase because the reset could come from a ioctl.
2242	 */
2243	if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2244		goto unlock;
2245	conn = session->leadconn;
2246
2247	/* only have one tmf outstanding at a time */
2248	if (conn->tmf_state != TMF_INITIAL)
2249		goto unlock;
2250	conn->tmf_state = TMF_QUEUED;
2251
2252	hdr = &conn->tmhdr;
2253	iscsi_prep_lun_reset_pdu(sc, hdr);
2254
2255	if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2256				    session->lu_reset_timeout)) {
2257		rc = FAILED;
2258		goto unlock;
2259	}
2260
2261	switch (conn->tmf_state) {
2262	case TMF_SUCCESS:
2263		break;
2264	case TMF_TIMEDOUT:
2265		spin_unlock_bh(&session->lock);
2266		iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2267		goto done;
2268	default:
2269		conn->tmf_state = TMF_INITIAL;
2270		goto unlock;
2271	}
2272
2273	rc = SUCCESS;
2274	spin_unlock_bh(&session->lock);
2275
2276	iscsi_suspend_tx(conn);
2277
2278	spin_lock_bh(&session->lock);
2279	memset(hdr, 0, sizeof(*hdr));
2280	fail_scsi_tasks(conn, sc->device->lun, DID_ERROR);
2281	conn->tmf_state = TMF_INITIAL;
2282	spin_unlock_bh(&session->lock);
2283
2284	iscsi_start_tx(conn);
2285	goto done;
2286
2287unlock:
2288	spin_unlock_bh(&session->lock);
2289done:
2290	ISCSI_DBG_EH(session, "dev reset result = %s\n",
2291		     rc == SUCCESS ? "SUCCESS" : "FAILED");
2292	mutex_unlock(&session->eh_mutex);
2293	return rc;
2294}
2295EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
2296
2297void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
2298{
2299	struct iscsi_session *session = cls_session->dd_data;
2300
2301	spin_lock_bh(&session->lock);
2302	if (session->state != ISCSI_STATE_LOGGED_IN) {
2303		session->state = ISCSI_STATE_RECOVERY_FAILED;
2304		if (session->leadconn)
2305			wake_up(&session->leadconn->ehwait);
2306	}
2307	spin_unlock_bh(&session->lock);
2308}
2309EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
2310
2311/**
2312 * iscsi_eh_session_reset - drop session and attempt relogin
2313 * @sc: scsi command
2314 *
2315 * This function will wait for a relogin, session termination from
2316 * userspace, or a recovery/replacement timeout.
2317 */
2318int iscsi_eh_session_reset(struct scsi_cmnd *sc)
2319{
2320	struct iscsi_cls_session *cls_session;
2321	struct iscsi_session *session;
2322	struct iscsi_conn *conn;
2323
2324	cls_session = starget_to_session(scsi_target(sc->device));
2325	session = cls_session->dd_data;
2326	conn = session->leadconn;
2327
2328	mutex_lock(&session->eh_mutex);
2329	spin_lock_bh(&session->lock);
2330	if (session->state == ISCSI_STATE_TERMINATE) {
2331failed:
2332		ISCSI_DBG_EH(session,
2333			     "failing session reset: Could not log back into "
2334			     "%s, %s [age %d]\n", session->targetname,
2335			     conn->persistent_address, session->age);
2336		spin_unlock_bh(&session->lock);
2337		mutex_unlock(&session->eh_mutex);
2338		return FAILED;
2339	}
2340
2341	spin_unlock_bh(&session->lock);
 
 
 
2342	mutex_unlock(&session->eh_mutex);
2343	/*
2344	 * we drop the lock here but the leadconn cannot be destoyed while
2345	 * we are in the scsi eh
2346	 */
2347	iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
 
2348
2349	ISCSI_DBG_EH(session, "wait for relogin\n");
2350	wait_event_interruptible(conn->ehwait,
2351				 session->state == ISCSI_STATE_TERMINATE ||
2352				 session->state == ISCSI_STATE_LOGGED_IN ||
2353				 session->state == ISCSI_STATE_RECOVERY_FAILED);
2354	if (signal_pending(current))
2355		flush_signals(current);
2356
2357	mutex_lock(&session->eh_mutex);
2358	spin_lock_bh(&session->lock);
2359	if (session->state == ISCSI_STATE_LOGGED_IN) {
2360		ISCSI_DBG_EH(session,
2361			     "session reset succeeded for %s,%s\n",
2362			     session->targetname, conn->persistent_address);
2363	} else
2364		goto failed;
2365	spin_unlock_bh(&session->lock);
2366	mutex_unlock(&session->eh_mutex);
2367	return SUCCESS;
2368}
2369EXPORT_SYMBOL_GPL(iscsi_eh_session_reset);
2370
2371static void iscsi_prep_tgt_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2372{
2373	memset(hdr, 0, sizeof(*hdr));
2374	hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2375	hdr->flags = ISCSI_TM_FUNC_TARGET_WARM_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2376	hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2377	hdr->rtt = RESERVED_ITT;
2378}
2379
2380/**
2381 * iscsi_eh_target_reset - reset target
2382 * @sc: scsi command
2383 *
2384 * This will attempt to send a warm target reset.
2385 */
2386int iscsi_eh_target_reset(struct scsi_cmnd *sc)
2387{
2388	struct iscsi_cls_session *cls_session;
2389	struct iscsi_session *session;
2390	struct iscsi_conn *conn;
2391	struct iscsi_tm *hdr;
2392	int rc = FAILED;
2393
2394	cls_session = starget_to_session(scsi_target(sc->device));
2395	session = cls_session->dd_data;
2396
2397	ISCSI_DBG_EH(session, "tgt Reset [sc %p tgt %s]\n", sc,
2398		     session->targetname);
2399
2400	mutex_lock(&session->eh_mutex);
2401	spin_lock_bh(&session->lock);
2402	/*
2403	 * Just check if we are not logged in. We cannot check for
2404	 * the phase because the reset could come from a ioctl.
2405	 */
2406	if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2407		goto unlock;
2408	conn = session->leadconn;
2409
2410	/* only have one tmf outstanding at a time */
2411	if (conn->tmf_state != TMF_INITIAL)
2412		goto unlock;
2413	conn->tmf_state = TMF_QUEUED;
2414
2415	hdr = &conn->tmhdr;
2416	iscsi_prep_tgt_reset_pdu(sc, hdr);
2417
2418	if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2419				    session->tgt_reset_timeout)) {
2420		rc = FAILED;
2421		goto unlock;
2422	}
2423
2424	switch (conn->tmf_state) {
2425	case TMF_SUCCESS:
2426		break;
2427	case TMF_TIMEDOUT:
2428		spin_unlock_bh(&session->lock);
2429		iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2430		goto done;
2431	default:
2432		conn->tmf_state = TMF_INITIAL;
2433		goto unlock;
2434	}
2435
2436	rc = SUCCESS;
2437	spin_unlock_bh(&session->lock);
2438
2439	iscsi_suspend_tx(conn);
2440
2441	spin_lock_bh(&session->lock);
2442	memset(hdr, 0, sizeof(*hdr));
2443	fail_scsi_tasks(conn, -1, DID_ERROR);
2444	conn->tmf_state = TMF_INITIAL;
2445	spin_unlock_bh(&session->lock);
2446
2447	iscsi_start_tx(conn);
2448	goto done;
2449
2450unlock:
2451	spin_unlock_bh(&session->lock);
2452done:
2453	ISCSI_DBG_EH(session, "tgt %s reset result = %s\n", session->targetname,
2454		     rc == SUCCESS ? "SUCCESS" : "FAILED");
2455	mutex_unlock(&session->eh_mutex);
2456	return rc;
2457}
2458EXPORT_SYMBOL_GPL(iscsi_eh_target_reset);
2459
2460/**
2461 * iscsi_eh_recover_target - reset target and possibly the session
2462 * @sc: scsi command
2463 *
2464 * This will attempt to send a warm target reset. If that fails,
2465 * we will escalate to ERL0 session recovery.
2466 */
2467int iscsi_eh_recover_target(struct scsi_cmnd *sc)
2468{
2469	int rc;
2470
2471	rc = iscsi_eh_target_reset(sc);
2472	if (rc == FAILED)
2473		rc = iscsi_eh_session_reset(sc);
2474	return rc;
2475}
2476EXPORT_SYMBOL_GPL(iscsi_eh_recover_target);
2477
2478/*
2479 * Pre-allocate a pool of @max items of @item_size. By default, the pool
2480 * should be accessed via kfifo_{get,put} on q->queue.
2481 * Optionally, the caller can obtain the array of object pointers
2482 * by passing in a non-NULL @items pointer
2483 */
2484int
2485iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
2486{
2487	int i, num_arrays = 1;
2488
2489	memset(q, 0, sizeof(*q));
2490
2491	q->max = max;
2492
2493	/* If the user passed an items pointer, he wants a copy of
2494	 * the array. */
2495	if (items)
2496		num_arrays++;
2497	q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
2498	if (q->pool == NULL)
2499		return -ENOMEM;
2500
2501	kfifo_init(&q->queue, (void*)q->pool, max * sizeof(void*));
2502
2503	for (i = 0; i < max; i++) {
2504		q->pool[i] = kzalloc(item_size, GFP_KERNEL);
2505		if (q->pool[i] == NULL) {
2506			q->max = i;
2507			goto enomem;
2508		}
2509		kfifo_in(&q->queue, (void*)&q->pool[i], sizeof(void*));
2510	}
2511
2512	if (items) {
2513		*items = q->pool + max;
2514		memcpy(*items, q->pool, max * sizeof(void *));
2515	}
2516
2517	return 0;
2518
2519enomem:
2520	iscsi_pool_free(q);
2521	return -ENOMEM;
2522}
2523EXPORT_SYMBOL_GPL(iscsi_pool_init);
2524
2525void iscsi_pool_free(struct iscsi_pool *q)
2526{
2527	int i;
2528
2529	for (i = 0; i < q->max; i++)
2530		kfree(q->pool[i]);
2531	kfree(q->pool);
2532}
2533EXPORT_SYMBOL_GPL(iscsi_pool_free);
2534
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2535/**
2536 * iscsi_host_add - add host to system
2537 * @shost: scsi host
2538 * @pdev: parent device
2539 *
2540 * This should be called by partial offload and software iscsi drivers
2541 * to add a host to the system.
2542 */
2543int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
2544{
2545	if (!shost->can_queue)
2546		shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX;
2547
2548	if (!shost->cmd_per_lun)
2549		shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN;
2550
2551	if (!shost->transportt->eh_timed_out)
2552		shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
2553	return scsi_add_host(shost, pdev);
2554}
2555EXPORT_SYMBOL_GPL(iscsi_host_add);
2556
2557/**
2558 * iscsi_host_alloc - allocate a host and driver data
2559 * @sht: scsi host template
2560 * @dd_data_size: driver host data size
2561 * @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
2562 *
2563 * This should be called by partial offload and software iscsi drivers.
2564 * To access the driver specific memory use the iscsi_host_priv() macro.
2565 */
2566struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
2567				   int dd_data_size, bool xmit_can_sleep)
2568{
2569	struct Scsi_Host *shost;
2570	struct iscsi_host *ihost;
2571
2572	shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
2573	if (!shost)
2574		return NULL;
2575	ihost = shost_priv(shost);
2576
2577	if (xmit_can_sleep) {
2578		snprintf(ihost->workq_name, sizeof(ihost->workq_name),
2579			"iscsi_q_%d", shost->host_no);
2580		ihost->workq = create_singlethread_workqueue(ihost->workq_name);
 
 
2581		if (!ihost->workq)
2582			goto free_host;
2583	}
2584
2585	spin_lock_init(&ihost->lock);
2586	ihost->state = ISCSI_HOST_SETUP;
2587	ihost->num_sessions = 0;
2588	init_waitqueue_head(&ihost->session_removal_wq);
2589	return shost;
2590
2591free_host:
2592	scsi_host_put(shost);
2593	return NULL;
2594}
2595EXPORT_SYMBOL_GPL(iscsi_host_alloc);
2596
2597static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
2598{
2599	iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST);
2600}
2601
2602/**
2603 * iscsi_host_remove - remove host and sessions
2604 * @shost: scsi host
2605 *
2606 * If there are any sessions left, this will initiate the removal and wait
2607 * for the completion.
2608 */
2609void iscsi_host_remove(struct Scsi_Host *shost)
2610{
2611	struct iscsi_host *ihost = shost_priv(shost);
2612	unsigned long flags;
2613
2614	spin_lock_irqsave(&ihost->lock, flags);
2615	ihost->state = ISCSI_HOST_REMOVED;
2616	spin_unlock_irqrestore(&ihost->lock, flags);
2617
2618	iscsi_host_for_each_session(shost, iscsi_notify_host_removed);
2619	wait_event_interruptible(ihost->session_removal_wq,
2620				 ihost->num_sessions == 0);
2621	if (signal_pending(current))
2622		flush_signals(current);
2623
2624	scsi_remove_host(shost);
2625	if (ihost->workq)
2626		destroy_workqueue(ihost->workq);
2627}
2628EXPORT_SYMBOL_GPL(iscsi_host_remove);
2629
2630void iscsi_host_free(struct Scsi_Host *shost)
2631{
2632	struct iscsi_host *ihost = shost_priv(shost);
2633
 
 
 
2634	kfree(ihost->netdev);
2635	kfree(ihost->hwaddress);
2636	kfree(ihost->initiatorname);
2637	scsi_host_put(shost);
2638}
2639EXPORT_SYMBOL_GPL(iscsi_host_free);
2640
2641static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost)
2642{
2643	struct iscsi_host *ihost = shost_priv(shost);
2644	unsigned long flags;
2645
2646	shost = scsi_host_get(shost);
2647	if (!shost) {
2648		printk(KERN_ERR "Invalid state. Cannot notify host removal "
2649		      "of session teardown event because host already "
2650		      "removed.\n");
2651		return;
2652	}
2653
2654	spin_lock_irqsave(&ihost->lock, flags);
2655	ihost->num_sessions--;
2656	if (ihost->num_sessions == 0)
2657		wake_up(&ihost->session_removal_wq);
2658	spin_unlock_irqrestore(&ihost->lock, flags);
2659	scsi_host_put(shost);
2660}
2661
2662/**
2663 * iscsi_session_setup - create iscsi cls session and host and session
2664 * @iscsit: iscsi transport template
2665 * @shost: scsi host
2666 * @cmds_max: session can queue
 
2667 * @cmd_task_size: LLD task private data size
2668 * @initial_cmdsn: initial CmdSN
 
2669 *
2670 * This can be used by software iscsi_transports that allocate
2671 * a session per scsi host.
2672 *
2673 * Callers should set cmds_max to the largest total numer (mgmt + scsi) of
2674 * tasks they support. The iscsi layer reserves ISCSI_MGMT_CMDS_MAX tasks
2675 * for nop handling and login/logout requests.
2676 */
2677struct iscsi_cls_session *
2678iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
2679		    uint16_t cmds_max, int dd_size, int cmd_task_size,
2680		    uint32_t initial_cmdsn, unsigned int id)
2681{
2682	struct iscsi_host *ihost = shost_priv(shost);
2683	struct iscsi_session *session;
2684	struct iscsi_cls_session *cls_session;
2685	int cmd_i, scsi_cmds, total_cmds = cmds_max;
2686	unsigned long flags;
2687
2688	spin_lock_irqsave(&ihost->lock, flags);
2689	if (ihost->state == ISCSI_HOST_REMOVED) {
2690		spin_unlock_irqrestore(&ihost->lock, flags);
2691		return NULL;
2692	}
2693	ihost->num_sessions++;
2694	spin_unlock_irqrestore(&ihost->lock, flags);
2695
2696	if (!total_cmds)
2697		total_cmds = ISCSI_DEF_XMIT_CMDS_MAX;
2698	/*
2699	 * The iscsi layer needs some tasks for nop handling and tmfs,
2700	 * so the cmds_max must at least be greater than ISCSI_MGMT_CMDS_MAX
2701	 * + 1 command for scsi IO.
2702	 */
2703	if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
2704		printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2705		       "must be a power of two that is at least %d.\n",
2706		       total_cmds, ISCSI_TOTAL_CMDS_MIN);
2707		goto dec_session_count;
2708	}
2709
2710	if (total_cmds > ISCSI_TOTAL_CMDS_MAX) {
2711		printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2712		       "must be a power of 2 less than or equal to %d.\n",
2713		       cmds_max, ISCSI_TOTAL_CMDS_MAX);
2714		total_cmds = ISCSI_TOTAL_CMDS_MAX;
2715	}
2716
2717	if (!is_power_of_2(total_cmds)) {
2718		printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2719		       "must be a power of 2.\n", total_cmds);
2720		total_cmds = rounddown_pow_of_two(total_cmds);
2721		if (total_cmds < ISCSI_TOTAL_CMDS_MIN)
2722			return NULL;
2723		printk(KERN_INFO "iscsi: Rounding can_queue to %d.\n",
2724		       total_cmds);
2725	}
2726	scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX;
2727
2728	cls_session = iscsi_alloc_session(shost, iscsit,
2729					  sizeof(struct iscsi_session) +
2730					  dd_size);
2731	if (!cls_session)
2732		goto dec_session_count;
2733	session = cls_session->dd_data;
2734	session->cls_session = cls_session;
2735	session->host = shost;
2736	session->state = ISCSI_STATE_FREE;
2737	session->fast_abort = 1;
2738	session->tgt_reset_timeout = 30;
2739	session->lu_reset_timeout = 15;
2740	session->abort_timeout = 10;
2741	session->scsi_cmds_max = scsi_cmds;
2742	session->cmds_max = total_cmds;
2743	session->queued_cmdsn = session->cmdsn = initial_cmdsn;
2744	session->exp_cmdsn = initial_cmdsn + 1;
2745	session->max_cmdsn = initial_cmdsn + 1;
2746	session->max_r2t = 1;
2747	session->tt = iscsit;
2748	session->dd_data = cls_session->dd_data + sizeof(*session);
 
 
 
2749	mutex_init(&session->eh_mutex);
2750	spin_lock_init(&session->lock);
 
 
2751
2752	/* initialize SCSI PDU commands pool */
2753	if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
2754			    (void***)&session->cmds,
2755			    cmd_task_size + sizeof(struct iscsi_task)))
2756		goto cmdpool_alloc_fail;
2757
2758	/* pre-format cmds pool with ITT */
2759	for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
2760		struct iscsi_task *task = session->cmds[cmd_i];
2761
2762		if (cmd_task_size)
2763			task->dd_data = &task[1];
2764		task->itt = cmd_i;
2765		task->state = ISCSI_TASK_FREE;
2766		INIT_LIST_HEAD(&task->running);
2767	}
2768
2769	if (!try_module_get(iscsit->owner))
2770		goto module_get_fail;
2771
2772	if (iscsi_add_session(cls_session, id))
2773		goto cls_session_fail;
2774
2775	return cls_session;
2776
2777cls_session_fail:
2778	module_put(iscsit->owner);
2779module_get_fail:
2780	iscsi_pool_free(&session->cmdpool);
2781cmdpool_alloc_fail:
2782	iscsi_free_session(cls_session);
2783dec_session_count:
2784	iscsi_host_dec_session_cnt(shost);
2785	return NULL;
2786}
2787EXPORT_SYMBOL_GPL(iscsi_session_setup);
2788
2789/**
2790 * iscsi_session_teardown - destroy session, host, and cls_session
2791 * @cls_session: iscsi session
2792 *
2793 * The driver must have called iscsi_remove_session before
2794 * calling this.
2795 */
2796void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
2797{
2798	struct iscsi_session *session = cls_session->dd_data;
2799	struct module *owner = cls_session->transport->owner;
2800	struct Scsi_Host *shost = session->host;
2801
 
 
2802	iscsi_pool_free(&session->cmdpool);
2803
2804	kfree(session->password);
2805	kfree(session->password_in);
2806	kfree(session->username);
2807	kfree(session->username_in);
2808	kfree(session->targetname);
 
2809	kfree(session->initiatorname);
 
 
 
2810	kfree(session->ifacename);
 
 
 
 
2811
2812	iscsi_destroy_session(cls_session);
2813	iscsi_host_dec_session_cnt(shost);
2814	module_put(owner);
2815}
2816EXPORT_SYMBOL_GPL(iscsi_session_teardown);
2817
2818/**
2819 * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
2820 * @cls_session: iscsi_cls_session
2821 * @dd_size: private driver data size
2822 * @conn_idx: cid
2823 */
2824struct iscsi_cls_conn *
2825iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
2826		 uint32_t conn_idx)
2827{
2828	struct iscsi_session *session = cls_session->dd_data;
2829	struct iscsi_conn *conn;
2830	struct iscsi_cls_conn *cls_conn;
2831	char *data;
2832
2833	cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size,
2834				     conn_idx);
2835	if (!cls_conn)
2836		return NULL;
2837	conn = cls_conn->dd_data;
2838	memset(conn, 0, sizeof(*conn) + dd_size);
2839
2840	conn->dd_data = cls_conn->dd_data + sizeof(*conn);
2841	conn->session = session;
2842	conn->cls_conn = cls_conn;
2843	conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
2844	conn->id = conn_idx;
2845	conn->exp_statsn = 0;
2846	conn->tmf_state = TMF_INITIAL;
2847
2848	init_timer(&conn->transport_timer);
2849	conn->transport_timer.data = (unsigned long)conn;
2850	conn->transport_timer.function = iscsi_check_transport_timeouts;
2851
2852	INIT_LIST_HEAD(&conn->mgmtqueue);
2853	INIT_LIST_HEAD(&conn->cmdqueue);
2854	INIT_LIST_HEAD(&conn->requeue);
2855	INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
2856
2857	/* allocate login_task used for the login/text sequences */
2858	spin_lock_bh(&session->lock);
2859	if (!kfifo_out(&session->cmdpool.queue,
2860                         (void*)&conn->login_task,
2861			 sizeof(void*))) {
2862		spin_unlock_bh(&session->lock);
2863		goto login_task_alloc_fail;
2864	}
2865	spin_unlock_bh(&session->lock);
2866
2867	data = (char *) __get_free_pages(GFP_KERNEL,
2868					 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
2869	if (!data)
2870		goto login_task_data_alloc_fail;
2871	conn->login_task->data = conn->data = data;
2872
2873	init_timer(&conn->tmf_timer);
2874	init_waitqueue_head(&conn->ehwait);
2875
2876	return cls_conn;
2877
2878login_task_data_alloc_fail:
2879	kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
2880		    sizeof(void*));
2881login_task_alloc_fail:
2882	iscsi_destroy_conn(cls_conn);
2883	return NULL;
2884}
2885EXPORT_SYMBOL_GPL(iscsi_conn_setup);
2886
2887/**
2888 * iscsi_conn_teardown - teardown iscsi connection
2889 * cls_conn: iscsi class connection
2890 *
2891 * TODO: we may need to make this into a two step process
2892 * like scsi-mls remove + put host
2893 */
2894void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
2895{
2896	struct iscsi_conn *conn = cls_conn->dd_data;
2897	struct iscsi_session *session = conn->session;
2898	unsigned long flags;
2899
2900	del_timer_sync(&conn->transport_timer);
2901
2902	spin_lock_bh(&session->lock);
 
2903	conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
2904	if (session->leadconn == conn) {
2905		/*
2906		 * leading connection? then give up on recovery.
2907		 */
2908		session->state = ISCSI_STATE_TERMINATE;
2909		wake_up(&conn->ehwait);
2910	}
2911	spin_unlock_bh(&session->lock);
2912
2913	/*
2914	 * Block until all in-progress commands for this connection
2915	 * time out or fail.
2916	 */
2917	for (;;) {
2918		spin_lock_irqsave(session->host->host_lock, flags);
2919		if (!session->host->host_busy) { /* OK for ERL == 0 */
2920			spin_unlock_irqrestore(session->host->host_lock, flags);
2921			break;
2922		}
2923		spin_unlock_irqrestore(session->host->host_lock, flags);
2924		msleep_interruptible(500);
2925		iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
2926				  "host_busy %d host_failed %d\n",
2927				  session->host->host_busy,
2928				  session->host->host_failed);
2929		/*
2930		 * force eh_abort() to unblock
2931		 */
2932		wake_up(&conn->ehwait);
2933	}
 
2934
2935	/* flush queued up work because we free the connection below */
2936	iscsi_suspend_tx(conn);
2937
2938	spin_lock_bh(&session->lock);
2939	free_pages((unsigned long) conn->data,
2940		   get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
2941	kfree(conn->persistent_address);
 
 
 
2942	kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
2943		    sizeof(void*));
 
2944	if (session->leadconn == conn)
2945		session->leadconn = NULL;
2946	spin_unlock_bh(&session->lock);
 
2947
2948	iscsi_destroy_conn(cls_conn);
2949}
2950EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
2951
2952int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
2953{
2954	struct iscsi_conn *conn = cls_conn->dd_data;
2955	struct iscsi_session *session = conn->session;
2956
2957	if (!session) {
2958		iscsi_conn_printk(KERN_ERR, conn,
2959				  "can't start unbound connection\n");
2960		return -EPERM;
2961	}
2962
2963	if ((session->imm_data_en || !session->initial_r2t_en) &&
2964	     session->first_burst > session->max_burst) {
2965		iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
2966				  "first_burst %d max_burst %d\n",
2967				  session->first_burst, session->max_burst);
2968		return -EINVAL;
2969	}
2970
2971	if (conn->ping_timeout && !conn->recv_timeout) {
2972		iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
2973				  "zero. Using 5 seconds\n.");
2974		conn->recv_timeout = 5;
2975	}
2976
2977	if (conn->recv_timeout && !conn->ping_timeout) {
2978		iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
2979				  "zero. Using 5 seconds.\n");
2980		conn->ping_timeout = 5;
2981	}
2982
2983	spin_lock_bh(&session->lock);
2984	conn->c_stage = ISCSI_CONN_STARTED;
2985	session->state = ISCSI_STATE_LOGGED_IN;
2986	session->queued_cmdsn = session->cmdsn;
2987
2988	conn->last_recv = jiffies;
2989	conn->last_ping = jiffies;
2990	if (conn->recv_timeout && conn->ping_timeout)
2991		mod_timer(&conn->transport_timer,
2992			  jiffies + (conn->recv_timeout * HZ));
2993
2994	switch(conn->stop_stage) {
2995	case STOP_CONN_RECOVER:
2996		/*
2997		 * unblock eh_abort() if it is blocked. re-try all
2998		 * commands after successful recovery
2999		 */
3000		conn->stop_stage = 0;
3001		conn->tmf_state = TMF_INITIAL;
3002		session->age++;
3003		if (session->age == 16)
3004			session->age = 0;
3005		break;
3006	case STOP_CONN_TERM:
3007		conn->stop_stage = 0;
3008		break;
3009	default:
3010		break;
3011	}
3012	spin_unlock_bh(&session->lock);
3013
3014	iscsi_unblock_session(session->cls_session);
3015	wake_up(&conn->ehwait);
3016	return 0;
3017}
3018EXPORT_SYMBOL_GPL(iscsi_conn_start);
3019
3020static void
3021fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn)
3022{
3023	struct iscsi_task *task;
3024	int i, state;
3025
3026	for (i = 0; i < conn->session->cmds_max; i++) {
3027		task = conn->session->cmds[i];
3028		if (task->sc)
3029			continue;
3030
3031		if (task->state == ISCSI_TASK_FREE)
3032			continue;
3033
3034		ISCSI_DBG_SESSION(conn->session,
3035				  "failing mgmt itt 0x%x state %d\n",
3036				  task->itt, task->state);
 
 
 
 
 
 
 
3037		state = ISCSI_TASK_ABRT_SESS_RECOV;
3038		if (task->state == ISCSI_TASK_PENDING)
3039			state = ISCSI_TASK_COMPLETED;
3040		iscsi_complete_task(task, state);
3041
3042	}
3043}
3044
3045static void iscsi_start_session_recovery(struct iscsi_session *session,
3046					 struct iscsi_conn *conn, int flag)
3047{
 
 
3048	int old_stop_stage;
3049
3050	mutex_lock(&session->eh_mutex);
3051	spin_lock_bh(&session->lock);
3052	if (conn->stop_stage == STOP_CONN_TERM) {
3053		spin_unlock_bh(&session->lock);
3054		mutex_unlock(&session->eh_mutex);
3055		return;
3056	}
3057
3058	/*
3059	 * When this is called for the in_login state, we only want to clean
3060	 * up the login task and connection. We do not need to block and set
3061	 * the recovery state again
3062	 */
3063	if (flag == STOP_CONN_TERM)
3064		session->state = ISCSI_STATE_TERMINATE;
3065	else if (conn->stop_stage != STOP_CONN_RECOVER)
3066		session->state = ISCSI_STATE_IN_RECOVERY;
3067
3068	old_stop_stage = conn->stop_stage;
3069	conn->stop_stage = flag;
3070	spin_unlock_bh(&session->lock);
3071
3072	del_timer_sync(&conn->transport_timer);
3073	iscsi_suspend_tx(conn);
3074
3075	spin_lock_bh(&session->lock);
3076	conn->c_stage = ISCSI_CONN_STOPPED;
3077	spin_unlock_bh(&session->lock);
3078
3079	/*
3080	 * for connection level recovery we should not calculate
3081	 * header digest. conn->hdr_size used for optimization
3082	 * in hdr_extract() and will be re-negotiated at
3083	 * set_param() time.
3084	 */
3085	if (flag == STOP_CONN_RECOVER) {
3086		conn->hdrdgst_en = 0;
3087		conn->datadgst_en = 0;
3088		if (session->state == ISCSI_STATE_IN_RECOVERY &&
3089		    old_stop_stage != STOP_CONN_RECOVER) {
3090			ISCSI_DBG_SESSION(session, "blocking session\n");
3091			iscsi_block_session(session->cls_session);
3092		}
3093	}
3094
3095	/*
3096	 * flush queues.
3097	 */
3098	spin_lock_bh(&session->lock);
3099	fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED);
3100	fail_mgmt_tasks(session, conn);
3101	memset(&conn->tmhdr, 0, sizeof(conn->tmhdr));
3102	spin_unlock_bh(&session->lock);
3103	mutex_unlock(&session->eh_mutex);
3104}
3105
3106void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
3107{
3108	struct iscsi_conn *conn = cls_conn->dd_data;
3109	struct iscsi_session *session = conn->session;
3110
3111	switch (flag) {
3112	case STOP_CONN_RECOVER:
3113	case STOP_CONN_TERM:
3114		iscsi_start_session_recovery(session, conn, flag);
3115		break;
3116	default:
3117		iscsi_conn_printk(KERN_ERR, conn,
3118				  "invalid stop flag %d\n", flag);
3119	}
3120}
3121EXPORT_SYMBOL_GPL(iscsi_conn_stop);
3122
3123int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
3124		    struct iscsi_cls_conn *cls_conn, int is_leading)
3125{
3126	struct iscsi_session *session = cls_session->dd_data;
3127	struct iscsi_conn *conn = cls_conn->dd_data;
3128
3129	spin_lock_bh(&session->lock);
3130	if (is_leading)
3131		session->leadconn = conn;
3132	spin_unlock_bh(&session->lock);
3133
3134	/*
 
 
 
 
 
 
 
3135	 * Unblock xmitworker(), Login Phase will pass through.
3136	 */
3137	clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
3138	clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
3139	return 0;
3140}
3141EXPORT_SYMBOL_GPL(iscsi_conn_bind);
3142
3143static int iscsi_switch_str_param(char **param, char *new_val_buf)
3144{
3145	char *new_val;
3146
3147	if (*param) {
3148		if (!strcmp(*param, new_val_buf))
3149			return 0;
3150	}
3151
3152	new_val = kstrdup(new_val_buf, GFP_NOIO);
3153	if (!new_val)
3154		return -ENOMEM;
3155
3156	kfree(*param);
3157	*param = new_val;
3158	return 0;
3159}
 
3160
3161int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
3162		    enum iscsi_param param, char *buf, int buflen)
3163{
3164	struct iscsi_conn *conn = cls_conn->dd_data;
3165	struct iscsi_session *session = conn->session;
3166	uint32_t value;
3167
3168	switch(param) {
3169	case ISCSI_PARAM_FAST_ABORT:
3170		sscanf(buf, "%d", &session->fast_abort);
3171		break;
3172	case ISCSI_PARAM_ABORT_TMO:
3173		sscanf(buf, "%d", &session->abort_timeout);
3174		break;
3175	case ISCSI_PARAM_LU_RESET_TMO:
3176		sscanf(buf, "%d", &session->lu_reset_timeout);
3177		break;
3178	case ISCSI_PARAM_TGT_RESET_TMO:
3179		sscanf(buf, "%d", &session->tgt_reset_timeout);
3180		break;
3181	case ISCSI_PARAM_PING_TMO:
3182		sscanf(buf, "%d", &conn->ping_timeout);
3183		break;
3184	case ISCSI_PARAM_RECV_TMO:
3185		sscanf(buf, "%d", &conn->recv_timeout);
3186		break;
3187	case ISCSI_PARAM_MAX_RECV_DLENGTH:
3188		sscanf(buf, "%d", &conn->max_recv_dlength);
3189		break;
3190	case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3191		sscanf(buf, "%d", &conn->max_xmit_dlength);
3192		break;
3193	case ISCSI_PARAM_HDRDGST_EN:
3194		sscanf(buf, "%d", &conn->hdrdgst_en);
3195		break;
3196	case ISCSI_PARAM_DATADGST_EN:
3197		sscanf(buf, "%d", &conn->datadgst_en);
3198		break;
3199	case ISCSI_PARAM_INITIAL_R2T_EN:
3200		sscanf(buf, "%d", &session->initial_r2t_en);
3201		break;
3202	case ISCSI_PARAM_MAX_R2T:
3203		sscanf(buf, "%d", &session->max_r2t);
3204		break;
3205	case ISCSI_PARAM_IMM_DATA_EN:
3206		sscanf(buf, "%d", &session->imm_data_en);
3207		break;
3208	case ISCSI_PARAM_FIRST_BURST:
3209		sscanf(buf, "%d", &session->first_burst);
3210		break;
3211	case ISCSI_PARAM_MAX_BURST:
3212		sscanf(buf, "%d", &session->max_burst);
3213		break;
3214	case ISCSI_PARAM_PDU_INORDER_EN:
3215		sscanf(buf, "%d", &session->pdu_inorder_en);
3216		break;
3217	case ISCSI_PARAM_DATASEQ_INORDER_EN:
3218		sscanf(buf, "%d", &session->dataseq_inorder_en);
3219		break;
3220	case ISCSI_PARAM_ERL:
3221		sscanf(buf, "%d", &session->erl);
3222		break;
3223	case ISCSI_PARAM_IFMARKER_EN:
3224		sscanf(buf, "%d", &value);
3225		BUG_ON(value);
3226		break;
3227	case ISCSI_PARAM_OFMARKER_EN:
3228		sscanf(buf, "%d", &value);
3229		BUG_ON(value);
3230		break;
3231	case ISCSI_PARAM_EXP_STATSN:
3232		sscanf(buf, "%u", &conn->exp_statsn);
3233		break;
3234	case ISCSI_PARAM_USERNAME:
3235		return iscsi_switch_str_param(&session->username, buf);
3236	case ISCSI_PARAM_USERNAME_IN:
3237		return iscsi_switch_str_param(&session->username_in, buf);
3238	case ISCSI_PARAM_PASSWORD:
3239		return iscsi_switch_str_param(&session->password, buf);
3240	case ISCSI_PARAM_PASSWORD_IN:
3241		return iscsi_switch_str_param(&session->password_in, buf);
3242	case ISCSI_PARAM_TARGET_NAME:
3243		return iscsi_switch_str_param(&session->targetname, buf);
 
 
3244	case ISCSI_PARAM_TPGT:
3245		sscanf(buf, "%d", &session->tpgt);
3246		break;
3247	case ISCSI_PARAM_PERSISTENT_PORT:
3248		sscanf(buf, "%d", &conn->persistent_port);
3249		break;
3250	case ISCSI_PARAM_PERSISTENT_ADDRESS:
3251		return iscsi_switch_str_param(&conn->persistent_address, buf);
3252	case ISCSI_PARAM_IFACE_NAME:
3253		return iscsi_switch_str_param(&session->ifacename, buf);
3254	case ISCSI_PARAM_INITIATOR_NAME:
3255		return iscsi_switch_str_param(&session->initiatorname, buf);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3256	default:
3257		return -ENOSYS;
3258	}
3259
3260	return 0;
3261}
3262EXPORT_SYMBOL_GPL(iscsi_set_param);
3263
3264int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
3265			    enum iscsi_param param, char *buf)
3266{
3267	struct iscsi_session *session = cls_session->dd_data;
3268	int len;
3269
3270	switch(param) {
3271	case ISCSI_PARAM_FAST_ABORT:
3272		len = sprintf(buf, "%d\n", session->fast_abort);
3273		break;
3274	case ISCSI_PARAM_ABORT_TMO:
3275		len = sprintf(buf, "%d\n", session->abort_timeout);
3276		break;
3277	case ISCSI_PARAM_LU_RESET_TMO:
3278		len = sprintf(buf, "%d\n", session->lu_reset_timeout);
3279		break;
3280	case ISCSI_PARAM_TGT_RESET_TMO:
3281		len = sprintf(buf, "%d\n", session->tgt_reset_timeout);
3282		break;
3283	case ISCSI_PARAM_INITIAL_R2T_EN:
3284		len = sprintf(buf, "%d\n", session->initial_r2t_en);
3285		break;
3286	case ISCSI_PARAM_MAX_R2T:
3287		len = sprintf(buf, "%hu\n", session->max_r2t);
3288		break;
3289	case ISCSI_PARAM_IMM_DATA_EN:
3290		len = sprintf(buf, "%d\n", session->imm_data_en);
3291		break;
3292	case ISCSI_PARAM_FIRST_BURST:
3293		len = sprintf(buf, "%u\n", session->first_burst);
3294		break;
3295	case ISCSI_PARAM_MAX_BURST:
3296		len = sprintf(buf, "%u\n", session->max_burst);
3297		break;
3298	case ISCSI_PARAM_PDU_INORDER_EN:
3299		len = sprintf(buf, "%d\n", session->pdu_inorder_en);
3300		break;
3301	case ISCSI_PARAM_DATASEQ_INORDER_EN:
3302		len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
 
 
 
3303		break;
3304	case ISCSI_PARAM_ERL:
3305		len = sprintf(buf, "%d\n", session->erl);
3306		break;
3307	case ISCSI_PARAM_TARGET_NAME:
3308		len = sprintf(buf, "%s\n", session->targetname);
 
 
 
3309		break;
3310	case ISCSI_PARAM_TPGT:
3311		len = sprintf(buf, "%d\n", session->tpgt);
3312		break;
3313	case ISCSI_PARAM_USERNAME:
3314		len = sprintf(buf, "%s\n", session->username);
3315		break;
3316	case ISCSI_PARAM_USERNAME_IN:
3317		len = sprintf(buf, "%s\n", session->username_in);
3318		break;
3319	case ISCSI_PARAM_PASSWORD:
3320		len = sprintf(buf, "%s\n", session->password);
3321		break;
3322	case ISCSI_PARAM_PASSWORD_IN:
3323		len = sprintf(buf, "%s\n", session->password_in);
3324		break;
3325	case ISCSI_PARAM_IFACE_NAME:
3326		len = sprintf(buf, "%s\n", session->ifacename);
3327		break;
3328	case ISCSI_PARAM_INITIATOR_NAME:
3329		len = sprintf(buf, "%s\n", session->initiatorname);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3330		break;
3331	default:
3332		return -ENOSYS;
3333	}
3334
3335	return len;
3336}
3337EXPORT_SYMBOL_GPL(iscsi_session_get_param);
3338
3339int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
3340			      enum iscsi_param param, char *buf)
3341{
3342	struct sockaddr_in6 *sin6 = NULL;
3343	struct sockaddr_in *sin = NULL;
3344	int len;
3345
3346	switch (addr->ss_family) {
3347	case AF_INET:
3348		sin = (struct sockaddr_in *)addr;
3349		break;
3350	case AF_INET6:
3351		sin6 = (struct sockaddr_in6 *)addr;
3352		break;
3353	default:
3354		return -EINVAL;
3355	}
3356
3357	switch (param) {
3358	case ISCSI_PARAM_CONN_ADDRESS:
3359	case ISCSI_HOST_PARAM_IPADDRESS:
3360		if (sin)
3361			len = sprintf(buf, "%pI4\n", &sin->sin_addr.s_addr);
3362		else
3363			len = sprintf(buf, "%pI6\n", &sin6->sin6_addr);
3364		break;
3365	case ISCSI_PARAM_CONN_PORT:
 
3366		if (sin)
3367			len = sprintf(buf, "%hu\n", be16_to_cpu(sin->sin_port));
3368		else
3369			len = sprintf(buf, "%hu\n",
3370				      be16_to_cpu(sin6->sin6_port));
3371		break;
3372	default:
3373		return -EINVAL;
3374	}
3375
3376	return len;
3377}
3378EXPORT_SYMBOL_GPL(iscsi_conn_get_addr_param);
3379
3380int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
3381			 enum iscsi_param param, char *buf)
3382{
3383	struct iscsi_conn *conn = cls_conn->dd_data;
3384	int len;
3385
3386	switch(param) {
3387	case ISCSI_PARAM_PING_TMO:
3388		len = sprintf(buf, "%u\n", conn->ping_timeout);
3389		break;
3390	case ISCSI_PARAM_RECV_TMO:
3391		len = sprintf(buf, "%u\n", conn->recv_timeout);
3392		break;
3393	case ISCSI_PARAM_MAX_RECV_DLENGTH:
3394		len = sprintf(buf, "%u\n", conn->max_recv_dlength);
3395		break;
3396	case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3397		len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
3398		break;
3399	case ISCSI_PARAM_HDRDGST_EN:
3400		len = sprintf(buf, "%d\n", conn->hdrdgst_en);
3401		break;
3402	case ISCSI_PARAM_DATADGST_EN:
3403		len = sprintf(buf, "%d\n", conn->datadgst_en);
3404		break;
3405	case ISCSI_PARAM_IFMARKER_EN:
3406		len = sprintf(buf, "%d\n", conn->ifmarker_en);
3407		break;
3408	case ISCSI_PARAM_OFMARKER_EN:
3409		len = sprintf(buf, "%d\n", conn->ofmarker_en);
3410		break;
3411	case ISCSI_PARAM_EXP_STATSN:
3412		len = sprintf(buf, "%u\n", conn->exp_statsn);
3413		break;
3414	case ISCSI_PARAM_PERSISTENT_PORT:
3415		len = sprintf(buf, "%d\n", conn->persistent_port);
3416		break;
3417	case ISCSI_PARAM_PERSISTENT_ADDRESS:
3418		len = sprintf(buf, "%s\n", conn->persistent_address);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3419		break;
3420	default:
3421		return -ENOSYS;
3422	}
3423
3424	return len;
3425}
3426EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
3427
3428int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3429			 char *buf)
3430{
3431	struct iscsi_host *ihost = shost_priv(shost);
3432	int len;
3433
3434	switch (param) {
3435	case ISCSI_HOST_PARAM_NETDEV_NAME:
3436		len = sprintf(buf, "%s\n", ihost->netdev);
3437		break;
3438	case ISCSI_HOST_PARAM_HWADDRESS:
3439		len = sprintf(buf, "%s\n", ihost->hwaddress);
3440		break;
3441	case ISCSI_HOST_PARAM_INITIATOR_NAME:
3442		len = sprintf(buf, "%s\n", ihost->initiatorname);
3443		break;
3444	default:
3445		return -ENOSYS;
3446	}
3447
3448	return len;
3449}
3450EXPORT_SYMBOL_GPL(iscsi_host_get_param);
3451
3452int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3453			 char *buf, int buflen)
3454{
3455	struct iscsi_host *ihost = shost_priv(shost);
3456
3457	switch (param) {
3458	case ISCSI_HOST_PARAM_NETDEV_NAME:
3459		return iscsi_switch_str_param(&ihost->netdev, buf);
3460	case ISCSI_HOST_PARAM_HWADDRESS:
3461		return iscsi_switch_str_param(&ihost->hwaddress, buf);
3462	case ISCSI_HOST_PARAM_INITIATOR_NAME:
3463		return iscsi_switch_str_param(&ihost->initiatorname, buf);
3464	default:
3465		return -ENOSYS;
3466	}
3467
3468	return 0;
3469}
3470EXPORT_SYMBOL_GPL(iscsi_host_set_param);
3471
3472MODULE_AUTHOR("Mike Christie");
3473MODULE_DESCRIPTION("iSCSI library functions");
3474MODULE_LICENSE("GPL");