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v6.8
   1/*
   2 * iSCSI Initiator over iSER Data-Path
   3 *
   4 * Copyright (C) 2004 Dmitry Yusupov
   5 * Copyright (C) 2004 Alex Aizman
   6 * Copyright (C) 2005 Mike Christie
   7 * Copyright (c) 2005, 2006 Voltaire, Inc. All rights reserved.
   8 * Copyright (c) 2013-2014 Mellanox Technologies. All rights reserved.
   9 * maintained by openib-general@openib.org
  10 *
  11 * This software is available to you under a choice of one of two
  12 * licenses.  You may choose to be licensed under the terms of the GNU
  13 * General Public License (GPL) Version 2, available from the file
  14 * COPYING in the main directory of this source tree, or the
  15 * OpenIB.org BSD license below:
  16 *
  17 *     Redistribution and use in source and binary forms, with or
  18 *     without modification, are permitted provided that the following
  19 *     conditions are met:
  20 *
  21 *	- Redistributions of source code must retain the above
  22 *	  copyright notice, this list of conditions and the following
  23 *	  disclaimer.
  24 *
  25 *	- Redistributions in binary form must reproduce the above
  26 *	  copyright notice, this list of conditions and the following
  27 *	  disclaimer in the documentation and/or other materials
  28 *	  provided with the distribution.
  29 *
  30 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  31 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  32 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  33 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  34 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  35 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  36 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  37 * SOFTWARE.
  38 *
  39 * Credits:
  40 *	Christoph Hellwig
  41 *	FUJITA Tomonori
  42 *	Arne Redlich
  43 *	Zhenyu Wang
  44 * Modified by:
  45 *      Erez Zilber
  46 */
  47
  48#include <linux/types.h>
  49#include <linux/list.h>
  50#include <linux/hardirq.h>
  51#include <linux/kfifo.h>
  52#include <linux/blkdev.h>
  53#include <linux/init.h>
  54#include <linux/ioctl.h>
  55#include <linux/cdev.h>
  56#include <linux/in.h>
  57#include <linux/net.h>
  58#include <linux/scatterlist.h>
  59#include <linux/delay.h>
  60#include <linux/slab.h>
  61#include <linux/module.h>
  62
  63#include <net/sock.h>
  64
  65#include <linux/uaccess.h>
  66
  67#include <scsi/scsi_cmnd.h>
  68#include <scsi/scsi_device.h>
  69#include <scsi/scsi_eh.h>
  70#include <scsi/scsi_tcq.h>
  71#include <scsi/scsi_host.h>
  72#include <scsi/scsi.h>
  73#include <scsi/scsi_transport_iscsi.h>
  74
  75#include "iscsi_iser.h"
  76
  77MODULE_DESCRIPTION("iSER (iSCSI Extensions for RDMA) Datamover");
  78MODULE_LICENSE("Dual BSD/GPL");
  79MODULE_AUTHOR("Alex Nezhinsky, Dan Bar Dov, Or Gerlitz");
 
  80
  81static const struct scsi_host_template iscsi_iser_sht;
  82static struct iscsi_transport iscsi_iser_transport;
  83static struct scsi_transport_template *iscsi_iser_scsi_transport;
  84static struct workqueue_struct *release_wq;
  85static DEFINE_MUTEX(unbind_iser_conn_mutex);
  86struct iser_global ig;
  87
  88int iser_debug_level = 0;
  89module_param_named(debug_level, iser_debug_level, int, S_IRUGO | S_IWUSR);
  90MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:disabled)");
  91
  92static int iscsi_iser_set(const char *val, const struct kernel_param *kp);
  93static const struct kernel_param_ops iscsi_iser_size_ops = {
  94	.set = iscsi_iser_set,
  95	.get = param_get_uint,
  96};
  97
  98static unsigned int iscsi_max_lun = 512;
  99module_param_cb(max_lun, &iscsi_iser_size_ops, &iscsi_max_lun, S_IRUGO);
 100MODULE_PARM_DESC(max_lun, "Max LUNs to allow per session, should > 0 (default:512)");
 101
 102unsigned int iser_max_sectors = ISER_DEF_MAX_SECTORS;
 103module_param_cb(max_sectors, &iscsi_iser_size_ops, &iser_max_sectors,
 104		S_IRUGO | S_IWUSR);
 105MODULE_PARM_DESC(max_sectors, "Max number of sectors in a single scsi command, should > 0 (default:1024)");
 106
 107bool iser_always_reg = true;
 108module_param_named(always_register, iser_always_reg, bool, S_IRUGO);
 109MODULE_PARM_DESC(always_register,
 110		 "Always register memory, even for continuous memory regions (default:true)");
 111
 112bool iser_pi_enable = false;
 113module_param_named(pi_enable, iser_pi_enable, bool, S_IRUGO);
 114MODULE_PARM_DESC(pi_enable, "Enable T10-PI offload support (default:disabled)");
 115
 116static int iscsi_iser_set(const char *val, const struct kernel_param *kp)
 117{
 118	int ret;
 119	unsigned int n = 0;
 120
 121	ret = kstrtouint(val, 10, &n);
 122	if (ret != 0 || n == 0)
 123		return -EINVAL;
 124
 125	return param_set_uint(val, kp);
 126}
 127
 128/*
 129 * iscsi_iser_recv() - Process a successful recv completion
 130 * @conn:         iscsi connection
 131 * @hdr:          iscsi header
 132 * @rx_data:      buffer containing receive data payload
 133 * @rx_data_len:  length of rx_data
 134 *
 135 * Notes: In case of data length errors or iscsi PDU completion failures
 136 *        this routine will signal iscsi layer of connection failure.
 137 */
 138void iscsi_iser_recv(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 139		     char *rx_data, int rx_data_len)
 
 140{
 141	int rc = 0;
 142	int datalen;
 143
 144	/* verify PDU length */
 145	datalen = ntoh24(hdr->dlength);
 146	if (datalen > rx_data_len || (datalen + 4) < rx_data_len) {
 147		iser_err("wrong datalen %d (hdr), %d (IB)\n",
 148			datalen, rx_data_len);
 149		rc = ISCSI_ERR_DATALEN;
 150		goto error;
 151	}
 152
 153	if (datalen != rx_data_len)
 154		iser_dbg("aligned datalen (%d) hdr, %d (IB)\n",
 155			datalen, rx_data_len);
 156
 157	rc = iscsi_complete_pdu(conn, hdr, rx_data, rx_data_len);
 158	if (rc && rc != ISCSI_ERR_NO_SCSI_CMD)
 159		goto error;
 160
 161	return;
 162error:
 163	iscsi_conn_failure(conn, rc);
 164}
 165
 166/**
 167 * iscsi_iser_pdu_alloc() - allocate an iscsi-iser PDU
 168 * @task:     iscsi task
 169 * @opcode:   iscsi command opcode
 170 *
 171 * Netes: This routine can't fail, just assign iscsi task
 172 *        hdr and max hdr size.
 173 */
 174static int iscsi_iser_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
 
 175{
 176	struct iscsi_iser_task *iser_task = task->dd_data;
 177
 178	task->hdr = (struct iscsi_hdr *)&iser_task->desc.iscsi_header;
 179	task->hdr_max = sizeof(iser_task->desc.iscsi_header);
 180
 181	return 0;
 182}
 183
 184/**
 185 * iser_initialize_task_headers() - Initialize task headers
 186 * @task:       iscsi task
 187 * @tx_desc:    iser tx descriptor
 188 *
 189 * Notes:
 190 * This routine may race with iser teardown flow for scsi
 191 * error handling TMFs. So for TMF we should acquire the
 192 * state mutex to avoid dereferencing the IB device which
 193 * may have already been terminated.
 194 */
 195int iser_initialize_task_headers(struct iscsi_task *task,
 196				 struct iser_tx_desc *tx_desc)
 
 197{
 198	struct iser_conn *iser_conn = task->conn->dd_data;
 199	struct iser_device *device = iser_conn->ib_conn.device;
 200	struct iscsi_iser_task *iser_task = task->dd_data;
 201	u64 dma_addr;
 
 
 202
 203	if (unlikely(iser_conn->state != ISER_CONN_UP))
 204		return -ENODEV;
 
 
 
 
 
 205
 206	dma_addr = ib_dma_map_single(device->ib_device, (void *)tx_desc,
 207				ISER_HEADERS_LEN, DMA_TO_DEVICE);
 208	if (ib_dma_mapping_error(device->ib_device, dma_addr))
 209		return -ENOMEM;
 
 
 210
 211	tx_desc->inv_wr.next = NULL;
 212	tx_desc->reg_wr.wr.next = NULL;
 213	tx_desc->mapped = true;
 214	tx_desc->dma_addr = dma_addr;
 215	tx_desc->tx_sg[0].addr   = tx_desc->dma_addr;
 216	tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
 217	tx_desc->tx_sg[0].lkey   = device->pd->local_dma_lkey;
 218
 219	iser_task->iser_conn = iser_conn;
 
 
 
 220
 221	return 0;
 222}
 223
 224/**
 225 * iscsi_iser_task_init() - Initialize iscsi-iser task
 226 * @task: iscsi task
 227 *
 228 * Initialize the task for the scsi command or mgmt command.
 229 *
 230 * Return: Returns zero on success or -ENOMEM when failing
 231 *         to init task headers (dma mapping error).
 232 */
 233static int iscsi_iser_task_init(struct iscsi_task *task)
 
 234{
 235	struct iscsi_iser_task *iser_task = task->dd_data;
 236	int ret;
 237
 238	ret = iser_initialize_task_headers(task, &iser_task->desc);
 239	if (ret) {
 240		iser_err("Failed to init task %p, err = %d\n",
 241			 iser_task, ret);
 242		return ret;
 243	}
 244
 245	/* mgmt task */
 246	if (!task->sc)
 247		return 0;
 248
 249	iser_task->command_sent = 0;
 250	iser_task_rdma_init(iser_task);
 251	iser_task->sc = task->sc;
 252
 253	return 0;
 254}
 255
 256/**
 257 * iscsi_iser_mtask_xmit() - xmit management (immediate) task
 258 * @conn: iscsi connection
 259 * @task: task management task
 260 *
 261 * Notes:
 262 *	The function can return -EAGAIN in which case caller must
 263 *	call it again later, or recover. '0' return code means successful
 264 *	xmit.
 265 *
 266 **/
 267static int iscsi_iser_mtask_xmit(struct iscsi_conn *conn,
 268				 struct iscsi_task *task)
 269{
 270	int error = 0;
 271
 272	iser_dbg("mtask xmit [cid %d itt 0x%x]\n", conn->id, task->itt);
 273
 274	error = iser_send_control(conn, task);
 275
 276	/* since iser xmits control with zero copy, tasks can not be recycled
 277	 * right after sending them.
 278	 * The recycling scheme is based on whether a response is expected
 279	 * - if yes, the task is recycled at iscsi_complete_pdu
 280	 * - if no,  the task is recycled at iser_snd_completion
 281	 */
 282	return error;
 283}
 284
 285static int iscsi_iser_task_xmit_unsol_data(struct iscsi_conn *conn,
 286					   struct iscsi_task *task)
 
 287{
 288	struct iscsi_r2t_info *r2t = &task->unsol_r2t;
 289	struct iscsi_data hdr;
 290	int error = 0;
 291
 292	/* Send data-out PDUs while there's still unsolicited data to send */
 293	while (iscsi_task_has_unsol_data(task)) {
 294		iscsi_prep_data_out_pdu(task, r2t, &hdr);
 295		iser_dbg("Sending data-out: itt 0x%x, data count %d\n",
 296			   hdr.itt, r2t->data_count);
 297
 298		/* the buffer description has been passed with the command */
 299		/* Send the command */
 300		error = iser_send_data_out(conn, task, &hdr);
 301		if (error) {
 302			r2t->datasn--;
 303			goto iscsi_iser_task_xmit_unsol_data_exit;
 304		}
 305		r2t->sent += r2t->data_count;
 306		iser_dbg("Need to send %d more as data-out PDUs\n",
 307			   r2t->data_length - r2t->sent);
 308	}
 309
 310iscsi_iser_task_xmit_unsol_data_exit:
 311	return error;
 312}
 313
 314/**
 315 * iscsi_iser_task_xmit() - xmit iscsi-iser task
 316 * @task: iscsi task
 317 *
 318 * Return: zero on success or escalates $error on failure.
 319 */
 320static int iscsi_iser_task_xmit(struct iscsi_task *task)
 
 321{
 322	struct iscsi_conn *conn = task->conn;
 323	struct iscsi_iser_task *iser_task = task->dd_data;
 324	int error = 0;
 325
 326	if (!task->sc)
 327		return iscsi_iser_mtask_xmit(conn, task);
 328
 329	if (task->sc->sc_data_direction == DMA_TO_DEVICE) {
 330		BUG_ON(scsi_bufflen(task->sc) == 0);
 331
 332		iser_dbg("cmd [itt %x total %d imm %d unsol_data %d\n",
 333			   task->itt, scsi_bufflen(task->sc),
 334			   task->imm_count, task->unsol_r2t.data_length);
 335	}
 336
 337	iser_dbg("ctask xmit [cid %d itt 0x%x]\n",
 338		   conn->id, task->itt);
 339
 340	/* Send the cmd PDU */
 341	if (!iser_task->command_sent) {
 342		error = iser_send_command(conn, task);
 343		if (error)
 344			goto iscsi_iser_task_xmit_exit;
 345		iser_task->command_sent = 1;
 346	}
 347
 348	/* Send unsolicited data-out PDU(s) if necessary */
 349	if (iscsi_task_has_unsol_data(task))
 350		error = iscsi_iser_task_xmit_unsol_data(conn, task);
 351
 352 iscsi_iser_task_xmit_exit:
 353	return error;
 354}
 355
 356/**
 357 * iscsi_iser_cleanup_task() - cleanup an iscsi-iser task
 358 * @task: iscsi task
 359 *
 360 * Notes: In case the RDMA device is already NULL (might have
 361 *        been removed in DEVICE_REMOVAL CM event it will bail-out
 362 *        without doing dma unmapping.
 363 */
 364static void iscsi_iser_cleanup_task(struct iscsi_task *task)
 365{
 366	struct iscsi_iser_task *iser_task = task->dd_data;
 367	struct iser_tx_desc *tx_desc = &iser_task->desc;
 368	struct iser_conn *iser_conn = task->conn->dd_data;
 369	struct iser_device *device = iser_conn->ib_conn.device;
 370
 371	/* DEVICE_REMOVAL event might have already released the device */
 372	if (!device)
 373		return;
 374
 375	if (likely(tx_desc->mapped)) {
 376		ib_dma_unmap_single(device->ib_device, tx_desc->dma_addr,
 377				    ISER_HEADERS_LEN, DMA_TO_DEVICE);
 378		tx_desc->mapped = false;
 379	}
 380
 381	/* mgmt tasks do not need special cleanup */
 382	if (!task->sc)
 383		return;
 384
 385	if (iser_task->status == ISER_TASK_STATUS_STARTED) {
 386		iser_task->status = ISER_TASK_STATUS_COMPLETED;
 387		iser_task_rdma_finalize(iser_task);
 388	}
 389}
 390
 391/**
 392 * iscsi_iser_check_protection() - check protection information status of task.
 393 * @task:     iscsi task
 394 * @sector:   error sector if exsists (output)
 395 *
 396 * Return: zero if no data-integrity errors have occured
 397 *         0x1: data-integrity error occured in the guard-block
 398 *         0x2: data-integrity error occured in the reference tag
 399 *         0x3: data-integrity error occured in the application tag
 400 *
 401 *         In addition the error sector is marked.
 402 */
 403static u8 iscsi_iser_check_protection(struct iscsi_task *task, sector_t *sector)
 
 404{
 405	struct iscsi_iser_task *iser_task = task->dd_data;
 406	enum iser_data_dir dir = iser_task->dir[ISER_DIR_IN] ?
 407					ISER_DIR_IN : ISER_DIR_OUT;
 408
 409	return iser_check_task_pi_status(iser_task, dir, sector);
 
 
 
 
 
 410}
 411
 412/**
 413 * iscsi_iser_conn_create() - create a new iscsi-iser connection
 414 * @cls_session: iscsi class connection
 415 * @conn_idx:    connection index within the session (for MCS)
 416 *
 417 * Return: iscsi_cls_conn when iscsi_conn_setup succeeds or NULL
 418 *         otherwise.
 419 */
 420static struct iscsi_cls_conn *
 421iscsi_iser_conn_create(struct iscsi_cls_session *cls_session,
 422		       uint32_t conn_idx)
 423{
 424	struct iscsi_conn *conn;
 425	struct iscsi_cls_conn *cls_conn;
 426
 427	cls_conn = iscsi_conn_setup(cls_session, 0, conn_idx);
 428	if (!cls_conn)
 429		return NULL;
 430	conn = cls_conn->dd_data;
 431
 432	/*
 433	 * due to issues with the login code re iser sematics
 434	 * this not set in iscsi_conn_setup - FIXME
 435	 */
 436	conn->max_recv_dlength = ISER_RECV_DATA_SEG_LEN;
 437
 438	return cls_conn;
 439}
 440
 441/**
 442 * iscsi_iser_conn_bind() - bind iscsi and iser connection structures
 443 * @cls_session:     iscsi class session
 444 * @cls_conn:        iscsi class connection
 445 * @transport_eph:   transport end-point handle
 446 * @is_leading:      indicate if this is the session leading connection (MCS)
 447 *
 448 * Return: zero on success, $error if iscsi_conn_bind fails and
 449 *         -EINVAL in case end-point doesn't exists anymore or iser connection
 450 *         state is not UP (teardown already started).
 451 */
 452static int iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session,
 453				struct iscsi_cls_conn *cls_conn,
 454				uint64_t transport_eph, int is_leading)
 
 
 455{
 456	struct iscsi_conn *conn = cls_conn->dd_data;
 457	struct iser_conn *iser_conn;
 458	struct iscsi_endpoint *ep;
 459	int error;
 460
 461	error = iscsi_conn_bind(cls_session, cls_conn, is_leading);
 462	if (error)
 463		return error;
 464
 465	/* the transport ep handle comes from user space so it must be
 466	 * verified against the global ib connections list */
 467	ep = iscsi_lookup_endpoint(transport_eph);
 468	if (!ep) {
 469		iser_err("can't bind eph %llx\n",
 470			 (unsigned long long)transport_eph);
 471		return -EINVAL;
 472	}
 473	iser_conn = ep->dd_data;
 474
 475	mutex_lock(&iser_conn->state_mutex);
 476	if (iser_conn->state != ISER_CONN_UP) {
 477		error = -EINVAL;
 478		iser_err("iser_conn %p state is %d, teardown started\n",
 479			 iser_conn, iser_conn->state);
 480		goto out;
 481	}
 482
 483	error = iser_alloc_rx_descriptors(iser_conn, conn->session);
 484	if (error)
 485		goto out;
 486
 487	/* binds the iSER connection retrieved from the previously
 488	 * connected ep_handle to the iSCSI layer connection. exchanges
 489	 * connection pointers */
 490	iser_info("binding iscsi conn %p to iser_conn %p\n", conn, iser_conn);
 491
 492	conn->dd_data = iser_conn;
 493	iser_conn->iscsi_conn = conn;
 494
 495out:
 496	iscsi_put_endpoint(ep);
 497	mutex_unlock(&iser_conn->state_mutex);
 498	return error;
 499}
 500
 501/**
 502 * iscsi_iser_conn_start() - start iscsi-iser connection
 503 * @cls_conn: iscsi class connection
 504 *
 505 * Notes: Here iser intialize (or re-initialize) stop_completion as
 506 *        from this point iscsi must call conn_stop in session/connection
 507 *        teardown so iser transport must wait for it.
 508 */
 509static int iscsi_iser_conn_start(struct iscsi_cls_conn *cls_conn)
 
 510{
 511	struct iscsi_conn *iscsi_conn;
 512	struct iser_conn *iser_conn;
 513
 514	iscsi_conn = cls_conn->dd_data;
 515	iser_conn = iscsi_conn->dd_data;
 516	reinit_completion(&iser_conn->stop_completion);
 517
 518	return iscsi_conn_start(cls_conn);
 519}
 520
 521/**
 522 * iscsi_iser_conn_stop() - stop iscsi-iser connection
 523 * @cls_conn:  iscsi class connection
 524 * @flag:      indicate if recover or terminate (passed as is)
 525 *
 526 * Notes: Calling iscsi_conn_stop might theoretically race with
 527 *        DEVICE_REMOVAL event and dereference a previously freed RDMA device
 528 *        handle, so we call it under iser the state lock to protect against
 529 *        this kind of race.
 530 */
 531static void iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
 
 532{
 533	struct iscsi_conn *conn = cls_conn->dd_data;
 534	struct iser_conn *iser_conn = conn->dd_data;
 535
 536	iser_info("stopping iscsi_conn: %p, iser_conn: %p\n", conn, iser_conn);
 537
 538	/*
 539	 * Userspace may have goofed up and not bound the connection or
 540	 * might have only partially setup the connection.
 541	 */
 542	if (iser_conn) {
 543		mutex_lock(&iser_conn->state_mutex);
 544		mutex_lock(&unbind_iser_conn_mutex);
 545		iser_conn_terminate(iser_conn);
 546		iscsi_conn_stop(cls_conn, flag);
 547
 548		/* unbind */
 549		iser_conn->iscsi_conn = NULL;
 550		conn->dd_data = NULL;
 551		mutex_unlock(&unbind_iser_conn_mutex);
 552
 553		complete(&iser_conn->stop_completion);
 554		mutex_unlock(&iser_conn->state_mutex);
 555	} else {
 556		iscsi_conn_stop(cls_conn, flag);
 557	}
 558}
 559
 560/**
 561 * iscsi_iser_session_destroy() - destroy iscsi-iser session
 562 * @cls_session: iscsi class session
 563 *
 564 * Removes and free iscsi host.
 565 */
 566static void iscsi_iser_session_destroy(struct iscsi_cls_session *cls_session)
 
 567{
 568	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
 569
 570	iscsi_session_teardown(cls_session);
 571	iscsi_host_remove(shost, false);
 572	iscsi_host_free(shost);
 573}
 574
 575static inline unsigned int iser_dif_prot_caps(int prot_caps)
 
 576{
 577	int ret = 0;
 578
 579	if (prot_caps & IB_PROT_T10DIF_TYPE_1)
 580		ret |= SHOST_DIF_TYPE1_PROTECTION |
 581		       SHOST_DIX_TYPE0_PROTECTION |
 582		       SHOST_DIX_TYPE1_PROTECTION;
 583	if (prot_caps & IB_PROT_T10DIF_TYPE_2)
 584		ret |= SHOST_DIF_TYPE2_PROTECTION |
 585		       SHOST_DIX_TYPE2_PROTECTION;
 586	if (prot_caps & IB_PROT_T10DIF_TYPE_3)
 587		ret |= SHOST_DIF_TYPE3_PROTECTION |
 588		       SHOST_DIX_TYPE3_PROTECTION;
 589
 590	return ret;
 591}
 592
 593/**
 594 * iscsi_iser_session_create() - create an iscsi-iser session
 595 * @ep:             iscsi end-point handle
 596 * @cmds_max:       maximum commands in this session
 597 * @qdepth:         session command queue depth
 598 * @initial_cmdsn:  initiator command sequnce number
 599 *
 600 * Allocates and adds a scsi host, expose DIF supprot if
 601 * exists, and sets up an iscsi session.
 602 */
 603static struct iscsi_cls_session *
 604iscsi_iser_session_create(struct iscsi_endpoint *ep,
 605			  uint16_t cmds_max, uint16_t qdepth,
 606			  uint32_t initial_cmdsn)
 607{
 608	struct iscsi_cls_session *cls_session;
 
 609	struct Scsi_Host *shost;
 610	struct iser_conn *iser_conn = NULL;
 611	struct ib_conn *ib_conn;
 612	struct ib_device *ib_dev;
 613	u32 max_fr_sectors;
 
 614
 615	shost = iscsi_host_alloc(&iscsi_iser_sht, 0, 0);
 616	if (!shost)
 617		return NULL;
 618	shost->transportt = iscsi_iser_scsi_transport;
 619	shost->cmd_per_lun = qdepth;
 620	shost->max_lun = iscsi_max_lun;
 621	shost->max_id = 0;
 622	shost->max_channel = 0;
 623	shost->max_cmd_len = 16;
 624
 625	/*
 626	 * older userspace tools (before 2.0-870) did not pass us
 627	 * the leading conn's ep so this will be NULL;
 628	 */
 629	if (ep) {
 630		iser_conn = ep->dd_data;
 
 631		shost->sg_tablesize = iser_conn->scsi_sg_tablesize;
 632		shost->can_queue = min_t(u16, cmds_max, iser_conn->max_cmds);
 633
 634		mutex_lock(&iser_conn->state_mutex);
 635		if (iser_conn->state != ISER_CONN_UP) {
 636			iser_err("iser conn %p already started teardown\n",
 637				 iser_conn);
 638			mutex_unlock(&iser_conn->state_mutex);
 639			goto free_host;
 640		}
 641
 642		ib_conn = &iser_conn->ib_conn;
 643		ib_dev = ib_conn->device->ib_device;
 644		if (ib_conn->pi_support) {
 645			u32 sig_caps = ib_dev->attrs.sig_prot_cap;
 646
 647			shost->sg_prot_tablesize = shost->sg_tablesize;
 648			scsi_host_set_prot(shost, iser_dif_prot_caps(sig_caps));
 649			scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP |
 650						   SHOST_DIX_GUARD_CRC);
 651		}
 652
 653		if (!(ib_dev->attrs.kernel_cap_flags & IBK_SG_GAPS_REG))
 654			shost->virt_boundary_mask = SZ_4K - 1;
 
 
 
 
 655
 656		if (iscsi_host_add(shost, ib_dev->dev.parent)) {
 
 657			mutex_unlock(&iser_conn->state_mutex);
 658			goto free_host;
 659		}
 660		mutex_unlock(&iser_conn->state_mutex);
 661	} else {
 662		shost->can_queue = min_t(u16, cmds_max, ISER_DEF_XMIT_CMDS_MAX);
 663		if (iscsi_host_add(shost, NULL))
 664			goto free_host;
 665	}
 666
 667	max_fr_sectors = (shost->sg_tablesize * PAGE_SIZE) >> 9;
 
 
 
 
 
 
 668	shost->max_sectors = min(iser_max_sectors, max_fr_sectors);
 669
 670	iser_dbg("iser_conn %p, sg_tablesize %u, max_sectors %u\n",
 671		 iser_conn, shost->sg_tablesize,
 672		 shost->max_sectors);
 673
 674	if (shost->max_sectors < iser_max_sectors)
 675		iser_warn("max_sectors was reduced from %u to %u\n",
 676			  iser_max_sectors, shost->max_sectors);
 677
 678	cls_session = iscsi_session_setup(&iscsi_iser_transport, shost,
 679					  shost->can_queue, 0,
 680					  sizeof(struct iscsi_iser_task),
 681					  initial_cmdsn, 0);
 682	if (!cls_session)
 683		goto remove_host;
 
 684
 
 685	return cls_session;
 686
 687remove_host:
 688	iscsi_host_remove(shost, false);
 689free_host:
 690	iscsi_host_free(shost);
 691	return NULL;
 692}
 693
 694static int iscsi_iser_set_param(struct iscsi_cls_conn *cls_conn,
 695				enum iscsi_param param, char *buf, int buflen)
 
 696{
 697	int value;
 698
 699	switch (param) {
 700	case ISCSI_PARAM_MAX_RECV_DLENGTH:
 701		/* TBD */
 702		break;
 703	case ISCSI_PARAM_HDRDGST_EN:
 704		sscanf(buf, "%d", &value);
 705		if (value) {
 706			iser_err("DataDigest wasn't negotiated to None\n");
 707			return -EPROTO;
 708		}
 709		break;
 710	case ISCSI_PARAM_DATADGST_EN:
 711		sscanf(buf, "%d", &value);
 712		if (value) {
 713			iser_err("DataDigest wasn't negotiated to None\n");
 714			return -EPROTO;
 715		}
 716		break;
 717	case ISCSI_PARAM_IFMARKER_EN:
 718		sscanf(buf, "%d", &value);
 719		if (value) {
 720			iser_err("IFMarker wasn't negotiated to No\n");
 721			return -EPROTO;
 722		}
 723		break;
 724	case ISCSI_PARAM_OFMARKER_EN:
 725		sscanf(buf, "%d", &value);
 726		if (value) {
 727			iser_err("OFMarker wasn't negotiated to No\n");
 728			return -EPROTO;
 729		}
 730		break;
 731	default:
 732		return iscsi_set_param(cls_conn, param, buf, buflen);
 733	}
 734
 735	return 0;
 736}
 737
 738/**
 739 * iscsi_iser_conn_get_stats() - get iscsi connection statistics
 740 * @cls_conn:    iscsi class connection
 741 * @stats:       iscsi stats to output
 742 *
 743 * Output connection statistics.
 744 */
 745static void iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn,
 746				      struct iscsi_stats *stats)
 747{
 748	struct iscsi_conn *conn = cls_conn->dd_data;
 749
 750	stats->txdata_octets = conn->txdata_octets;
 751	stats->rxdata_octets = conn->rxdata_octets;
 752	stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
 753	stats->dataout_pdus = conn->dataout_pdus_cnt;
 754	stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
 755	stats->datain_pdus = conn->datain_pdus_cnt; /* always 0 */
 756	stats->r2t_pdus = conn->r2t_pdus_cnt; /* always 0 */
 757	stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
 758	stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
 759	stats->custom_length = 0;
 760}
 761
 762static int iscsi_iser_get_ep_param(struct iscsi_endpoint *ep,
 763				   enum iscsi_param param, char *buf)
 764{
 765	struct iser_conn *iser_conn = ep->dd_data;
 
 766
 767	switch (param) {
 768	case ISCSI_PARAM_CONN_PORT:
 769	case ISCSI_PARAM_CONN_ADDRESS:
 770		if (!iser_conn || !iser_conn->ib_conn.cma_id)
 771			return -ENOTCONN;
 772
 773		return iscsi_conn_get_addr_param((struct sockaddr_storage *)
 774				&iser_conn->ib_conn.cma_id->route.addr.dst_addr,
 775				param, buf);
 776	default:
 777		break;
 
 
 778	}
 779	return -ENOSYS;
 
 780}
 781
 782/**
 783 * iscsi_iser_ep_connect() - Initiate iSER connection establishment
 784 * @shost:          scsi_host
 785 * @dst_addr:       destination address
 786 * @non_blocking:   indicate if routine can block
 787 *
 788 * Allocate an iscsi endpoint, an iser_conn structure and bind them.
 789 * After that start RDMA connection establishment via rdma_cm. We
 790 * don't allocate iser_conn embedded in iscsi_endpoint since in teardown
 791 * the endpoint will be destroyed at ep_disconnect while iser_conn will
 792 * cleanup its resources asynchronuously.
 793 *
 794 * Return: iscsi_endpoint created by iscsi layer or ERR_PTR(error)
 795 *         if fails.
 796 */
 797static struct iscsi_endpoint *iscsi_iser_ep_connect(struct Scsi_Host *shost,
 798						    struct sockaddr *dst_addr,
 799						    int non_blocking)
 800{
 801	int err;
 802	struct iser_conn *iser_conn;
 803	struct iscsi_endpoint *ep;
 804
 805	ep = iscsi_create_endpoint(0);
 806	if (!ep)
 807		return ERR_PTR(-ENOMEM);
 808
 809	iser_conn = kzalloc(sizeof(*iser_conn), GFP_KERNEL);
 810	if (!iser_conn) {
 811		err = -ENOMEM;
 812		goto failure;
 813	}
 814
 815	ep->dd_data = iser_conn;
 816	iser_conn->ep = ep;
 817	iser_conn_init(iser_conn);
 818
 819	err = iser_connect(iser_conn, NULL, dst_addr, non_blocking);
 820	if (err)
 821		goto failure;
 822
 823	return ep;
 824failure:
 825	iscsi_destroy_endpoint(ep);
 826	return ERR_PTR(err);
 827}
 828
 829/**
 830 * iscsi_iser_ep_poll() - poll for iser connection establishment to complete
 831 * @ep:            iscsi endpoint (created at ep_connect)
 832 * @timeout_ms:    polling timeout allowed in ms.
 833 *
 834 * This routine boils down to waiting for up_completion signaling
 835 * that cma_id got CONNECTED event.
 836 *
 837 * Return: 1 if succeeded in connection establishment, 0 if timeout expired
 838 *         (libiscsi will retry will kick in) or -1 if interrupted by signal
 839 *         or more likely iser connection state transitioned to TEMINATING or
 840 *         DOWN during the wait period.
 841 */
 842static int iscsi_iser_ep_poll(struct iscsi_endpoint *ep, int timeout_ms)
 
 843{
 844	struct iser_conn *iser_conn = ep->dd_data;
 845	int rc;
 846
 847	rc = wait_for_completion_interruptible_timeout(&iser_conn->up_completion,
 848						       msecs_to_jiffies(timeout_ms));
 849	/* if conn establishment failed, return error code to iscsi */
 850	if (rc == 0) {
 851		mutex_lock(&iser_conn->state_mutex);
 852		if (iser_conn->state == ISER_CONN_TERMINATING ||
 853		    iser_conn->state == ISER_CONN_DOWN)
 854			rc = -1;
 855		mutex_unlock(&iser_conn->state_mutex);
 856	}
 857
 858	iser_info("iser conn %p rc = %d\n", iser_conn, rc);
 859
 860	if (rc > 0)
 861		return 1; /* success, this is the equivalent of EPOLLOUT */
 862	else if (!rc)
 863		return 0; /* timeout */
 864	else
 865		return rc; /* signal */
 866}
 867
 868/**
 869 * iscsi_iser_ep_disconnect() - Initiate connection teardown process
 870 * @ep:    iscsi endpoint handle
 871 *
 872 * This routine is not blocked by iser and RDMA termination process
 873 * completion as we queue a deffered work for iser/RDMA destruction
 874 * and cleanup or actually call it immediately in case we didn't pass
 875 * iscsi conn bind/start stage, thus it is safe.
 876 */
 877static void iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep)
 
 878{
 879	struct iser_conn *iser_conn = ep->dd_data;
 880
 881	iser_info("ep %p iser conn %p\n", ep, iser_conn);
 882
 883	mutex_lock(&iser_conn->state_mutex);
 884	iser_conn_terminate(iser_conn);
 885
 886	/*
 887	 * if iser_conn and iscsi_conn are bound, we must wait for
 888	 * iscsi_conn_stop and flush errors completion before freeing
 889	 * the iser resources. Otherwise we are safe to free resources
 890	 * immediately.
 891	 */
 892	if (iser_conn->iscsi_conn) {
 893		INIT_WORK(&iser_conn->release_work, iser_release_work);
 894		queue_work(release_wq, &iser_conn->release_work);
 895		mutex_unlock(&iser_conn->state_mutex);
 896	} else {
 897		iser_conn->state = ISER_CONN_DOWN;
 898		mutex_unlock(&iser_conn->state_mutex);
 899		iser_conn_release(iser_conn);
 900	}
 901
 902	iscsi_destroy_endpoint(ep);
 903}
 904
 905static umode_t iser_attr_is_visible(int param_type, int param)
 906{
 907	switch (param_type) {
 908	case ISCSI_HOST_PARAM:
 909		switch (param) {
 910		case ISCSI_HOST_PARAM_NETDEV_NAME:
 911		case ISCSI_HOST_PARAM_HWADDRESS:
 912		case ISCSI_HOST_PARAM_INITIATOR_NAME:
 913			return S_IRUGO;
 914		default:
 915			return 0;
 916		}
 917	case ISCSI_PARAM:
 918		switch (param) {
 919		case ISCSI_PARAM_MAX_RECV_DLENGTH:
 920		case ISCSI_PARAM_MAX_XMIT_DLENGTH:
 921		case ISCSI_PARAM_HDRDGST_EN:
 922		case ISCSI_PARAM_DATADGST_EN:
 923		case ISCSI_PARAM_CONN_ADDRESS:
 924		case ISCSI_PARAM_CONN_PORT:
 925		case ISCSI_PARAM_EXP_STATSN:
 926		case ISCSI_PARAM_PERSISTENT_ADDRESS:
 927		case ISCSI_PARAM_PERSISTENT_PORT:
 928		case ISCSI_PARAM_PING_TMO:
 929		case ISCSI_PARAM_RECV_TMO:
 930		case ISCSI_PARAM_INITIAL_R2T_EN:
 931		case ISCSI_PARAM_MAX_R2T:
 932		case ISCSI_PARAM_IMM_DATA_EN:
 933		case ISCSI_PARAM_FIRST_BURST:
 934		case ISCSI_PARAM_MAX_BURST:
 935		case ISCSI_PARAM_PDU_INORDER_EN:
 936		case ISCSI_PARAM_DATASEQ_INORDER_EN:
 937		case ISCSI_PARAM_TARGET_NAME:
 938		case ISCSI_PARAM_TPGT:
 939		case ISCSI_PARAM_USERNAME:
 940		case ISCSI_PARAM_PASSWORD:
 941		case ISCSI_PARAM_USERNAME_IN:
 942		case ISCSI_PARAM_PASSWORD_IN:
 943		case ISCSI_PARAM_FAST_ABORT:
 944		case ISCSI_PARAM_ABORT_TMO:
 945		case ISCSI_PARAM_LU_RESET_TMO:
 946		case ISCSI_PARAM_TGT_RESET_TMO:
 947		case ISCSI_PARAM_IFACE_NAME:
 948		case ISCSI_PARAM_INITIATOR_NAME:
 949		case ISCSI_PARAM_DISCOVERY_SESS:
 950			return S_IRUGO;
 951		default:
 952			return 0;
 953		}
 954	}
 955
 956	return 0;
 957}
 958
 959static const struct scsi_host_template iscsi_iser_sht = {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 960	.module                 = THIS_MODULE,
 961	.name                   = "iSCSI Initiator over iSER",
 962	.queuecommand           = iscsi_queuecommand,
 963	.change_queue_depth	= scsi_change_queue_depth,
 964	.sg_tablesize           = ISCSI_ISER_DEF_SG_TABLESIZE,
 965	.cmd_per_lun            = ISER_DEF_CMD_PER_LUN,
 966	.eh_timed_out		= iscsi_eh_cmd_timed_out,
 967	.eh_abort_handler       = iscsi_eh_abort,
 968	.eh_device_reset_handler= iscsi_eh_device_reset,
 969	.eh_target_reset_handler = iscsi_eh_recover_target,
 970	.target_alloc		= iscsi_target_alloc,
 
 
 971	.proc_name              = "iscsi_iser",
 972	.this_id                = -1,
 973	.track_queue_depth	= 1,
 974	.cmd_size		= sizeof(struct iscsi_cmd),
 975};
 976
 977static struct iscsi_transport iscsi_iser_transport = {
 978	.owner                  = THIS_MODULE,
 979	.name                   = "iser",
 980	.caps                   = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_TEXT_NEGO,
 981	/* session management */
 982	.create_session         = iscsi_iser_session_create,
 983	.destroy_session        = iscsi_iser_session_destroy,
 984	/* connection management */
 985	.create_conn            = iscsi_iser_conn_create,
 986	.bind_conn              = iscsi_iser_conn_bind,
 987	.unbind_conn		= iscsi_conn_unbind,
 988	.destroy_conn           = iscsi_conn_teardown,
 989	.attr_is_visible	= iser_attr_is_visible,
 990	.set_param              = iscsi_iser_set_param,
 991	.get_conn_param		= iscsi_conn_get_param,
 992	.get_ep_param		= iscsi_iser_get_ep_param,
 993	.get_session_param	= iscsi_session_get_param,
 994	.start_conn             = iscsi_iser_conn_start,
 995	.stop_conn              = iscsi_iser_conn_stop,
 996	/* iscsi host params */
 997	.get_host_param		= iscsi_host_get_param,
 998	.set_host_param		= iscsi_host_set_param,
 999	/* IO */
1000	.send_pdu		= iscsi_conn_send_pdu,
1001	.get_stats		= iscsi_iser_conn_get_stats,
1002	.init_task		= iscsi_iser_task_init,
1003	.xmit_task		= iscsi_iser_task_xmit,
1004	.cleanup_task		= iscsi_iser_cleanup_task,
1005	.alloc_pdu		= iscsi_iser_pdu_alloc,
1006	.check_protection	= iscsi_iser_check_protection,
1007	/* recovery */
1008	.session_recovery_timedout = iscsi_session_recovery_timedout,
1009
1010	.ep_connect             = iscsi_iser_ep_connect,
1011	.ep_poll                = iscsi_iser_ep_poll,
1012	.ep_disconnect          = iscsi_iser_ep_disconnect
1013};
1014
1015static int __init iser_init(void)
1016{
1017	int err;
1018
1019	iser_dbg("Starting iSER datamover...\n");
 
 
 
 
 
1020
1021	memset(&ig, 0, sizeof(struct iser_global));
1022
1023	ig.desc_cache = kmem_cache_create("iser_descriptors",
1024					  sizeof(struct iser_tx_desc),
1025					  0, SLAB_HWCACHE_ALIGN,
1026					  NULL);
1027	if (ig.desc_cache == NULL)
1028		return -ENOMEM;
1029
1030	/* device init is called only after the first addr resolution */
1031	mutex_init(&ig.device_list_mutex);
1032	INIT_LIST_HEAD(&ig.device_list);
1033	mutex_init(&ig.connlist_mutex);
1034	INIT_LIST_HEAD(&ig.connlist);
1035
1036	release_wq = alloc_workqueue("release workqueue", 0, 0);
1037	if (!release_wq) {
1038		iser_err("failed to allocate release workqueue\n");
1039		err = -ENOMEM;
1040		goto err_alloc_wq;
1041	}
1042
1043	iscsi_iser_scsi_transport = iscsi_register_transport(
1044							&iscsi_iser_transport);
1045	if (!iscsi_iser_scsi_transport) {
1046		iser_err("iscsi_register_transport failed\n");
1047		err = -EINVAL;
1048		goto err_reg;
1049	}
1050
1051	return 0;
1052
1053err_reg:
1054	destroy_workqueue(release_wq);
1055err_alloc_wq:
1056	kmem_cache_destroy(ig.desc_cache);
1057
1058	return err;
1059}
1060
1061static void __exit iser_exit(void)
1062{
1063	struct iser_conn *iser_conn, *n;
1064	int connlist_empty;
1065
1066	iser_dbg("Removing iSER datamover...\n");
1067	destroy_workqueue(release_wq);
1068
1069	mutex_lock(&ig.connlist_mutex);
1070	connlist_empty = list_empty(&ig.connlist);
1071	mutex_unlock(&ig.connlist_mutex);
1072
1073	if (!connlist_empty) {
1074		iser_err("Error cleanup stage completed but we still have iser "
1075			 "connections, destroying them anyway\n");
1076		list_for_each_entry_safe(iser_conn, n, &ig.connlist,
1077					 conn_list) {
1078			iser_conn_release(iser_conn);
1079		}
1080	}
1081
1082	iscsi_unregister_transport(&iscsi_iser_transport);
1083	kmem_cache_destroy(ig.desc_cache);
1084}
1085
1086module_init(iser_init);
1087module_exit(iser_exit);
v4.6
   1/*
   2 * iSCSI Initiator over iSER Data-Path
   3 *
   4 * Copyright (C) 2004 Dmitry Yusupov
   5 * Copyright (C) 2004 Alex Aizman
   6 * Copyright (C) 2005 Mike Christie
   7 * Copyright (c) 2005, 2006 Voltaire, Inc. All rights reserved.
   8 * Copyright (c) 2013-2014 Mellanox Technologies. All rights reserved.
   9 * maintained by openib-general@openib.org
  10 *
  11 * This software is available to you under a choice of one of two
  12 * licenses.  You may choose to be licensed under the terms of the GNU
  13 * General Public License (GPL) Version 2, available from the file
  14 * COPYING in the main directory of this source tree, or the
  15 * OpenIB.org BSD license below:
  16 *
  17 *     Redistribution and use in source and binary forms, with or
  18 *     without modification, are permitted provided that the following
  19 *     conditions are met:
  20 *
  21 *	- Redistributions of source code must retain the above
  22 *	  copyright notice, this list of conditions and the following
  23 *	  disclaimer.
  24 *
  25 *	- Redistributions in binary form must reproduce the above
  26 *	  copyright notice, this list of conditions and the following
  27 *	  disclaimer in the documentation and/or other materials
  28 *	  provided with the distribution.
  29 *
  30 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  31 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  32 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  33 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  34 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  35 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  36 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  37 * SOFTWARE.
  38 *
  39 * Credits:
  40 *	Christoph Hellwig
  41 *	FUJITA Tomonori
  42 *	Arne Redlich
  43 *	Zhenyu Wang
  44 * Modified by:
  45 *      Erez Zilber
  46 */
  47
  48#include <linux/types.h>
  49#include <linux/list.h>
  50#include <linux/hardirq.h>
  51#include <linux/kfifo.h>
  52#include <linux/blkdev.h>
  53#include <linux/init.h>
  54#include <linux/ioctl.h>
  55#include <linux/cdev.h>
  56#include <linux/in.h>
  57#include <linux/net.h>
  58#include <linux/scatterlist.h>
  59#include <linux/delay.h>
  60#include <linux/slab.h>
  61#include <linux/module.h>
  62
  63#include <net/sock.h>
  64
  65#include <asm/uaccess.h>
  66
  67#include <scsi/scsi_cmnd.h>
  68#include <scsi/scsi_device.h>
  69#include <scsi/scsi_eh.h>
  70#include <scsi/scsi_tcq.h>
  71#include <scsi/scsi_host.h>
  72#include <scsi/scsi.h>
  73#include <scsi/scsi_transport_iscsi.h>
  74
  75#include "iscsi_iser.h"
  76
  77MODULE_DESCRIPTION("iSER (iSCSI Extensions for RDMA) Datamover");
  78MODULE_LICENSE("Dual BSD/GPL");
  79MODULE_AUTHOR("Alex Nezhinsky, Dan Bar Dov, Or Gerlitz");
  80MODULE_VERSION(DRV_VER);
  81
  82static struct scsi_host_template iscsi_iser_sht;
  83static struct iscsi_transport iscsi_iser_transport;
  84static struct scsi_transport_template *iscsi_iser_scsi_transport;
  85static struct workqueue_struct *release_wq;
 
  86struct iser_global ig;
  87
  88int iser_debug_level = 0;
  89module_param_named(debug_level, iser_debug_level, int, S_IRUGO | S_IWUSR);
  90MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:disabled)");
  91
 
 
 
 
 
 
  92static unsigned int iscsi_max_lun = 512;
  93module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
  94MODULE_PARM_DESC(max_lun, "Max LUNs to allow per session (default:512");
  95
  96unsigned int iser_max_sectors = ISER_DEF_MAX_SECTORS;
  97module_param_named(max_sectors, iser_max_sectors, uint, S_IRUGO | S_IWUSR);
  98MODULE_PARM_DESC(max_sectors, "Max number of sectors in a single scsi command (default:1024");
 
  99
 100bool iser_always_reg = true;
 101module_param_named(always_register, iser_always_reg, bool, S_IRUGO);
 102MODULE_PARM_DESC(always_register,
 103		 "Always register memory, even for continuous memory regions (default:true)");
 104
 105bool iser_pi_enable = false;
 106module_param_named(pi_enable, iser_pi_enable, bool, S_IRUGO);
 107MODULE_PARM_DESC(pi_enable, "Enable T10-PI offload support (default:disabled)");
 108
 109int iser_pi_guard;
 110module_param_named(pi_guard, iser_pi_guard, int, S_IRUGO);
 111MODULE_PARM_DESC(pi_guard, "T10-PI guard_type [deprecated]");
 
 
 
 
 
 
 
 
 112
 113/*
 114 * iscsi_iser_recv() - Process a successful recv completion
 115 * @conn:         iscsi connection
 116 * @hdr:          iscsi header
 117 * @rx_data:      buffer containing receive data payload
 118 * @rx_data_len:  length of rx_data
 119 *
 120 * Notes: In case of data length errors or iscsi PDU completion failures
 121 *        this routine will signal iscsi layer of connection failure.
 122 */
 123void
 124iscsi_iser_recv(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 125		char *rx_data, int rx_data_len)
 126{
 127	int rc = 0;
 128	int datalen;
 129
 130	/* verify PDU length */
 131	datalen = ntoh24(hdr->dlength);
 132	if (datalen > rx_data_len || (datalen + 4) < rx_data_len) {
 133		iser_err("wrong datalen %d (hdr), %d (IB)\n",
 134			datalen, rx_data_len);
 135		rc = ISCSI_ERR_DATALEN;
 136		goto error;
 137	}
 138
 139	if (datalen != rx_data_len)
 140		iser_dbg("aligned datalen (%d) hdr, %d (IB)\n",
 141			datalen, rx_data_len);
 142
 143	rc = iscsi_complete_pdu(conn, hdr, rx_data, rx_data_len);
 144	if (rc && rc != ISCSI_ERR_NO_SCSI_CMD)
 145		goto error;
 146
 147	return;
 148error:
 149	iscsi_conn_failure(conn, rc);
 150}
 151
 152/**
 153 * iscsi_iser_pdu_alloc() - allocate an iscsi-iser PDU
 154 * @task:     iscsi task
 155 * @opcode:   iscsi command opcode
 156 *
 157 * Netes: This routine can't fail, just assign iscsi task
 158 *        hdr and max hdr size.
 159 */
 160static int
 161iscsi_iser_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
 162{
 163	struct iscsi_iser_task *iser_task = task->dd_data;
 164
 165	task->hdr = (struct iscsi_hdr *)&iser_task->desc.iscsi_header;
 166	task->hdr_max = sizeof(iser_task->desc.iscsi_header);
 167
 168	return 0;
 169}
 170
 171/**
 172 * iser_initialize_task_headers() - Initialize task headers
 173 * @task:       iscsi task
 174 * @tx_desc:    iser tx descriptor
 175 *
 176 * Notes:
 177 * This routine may race with iser teardown flow for scsi
 178 * error handling TMFs. So for TMF we should acquire the
 179 * state mutex to avoid dereferencing the IB device which
 180 * may have already been terminated.
 181 */
 182int
 183iser_initialize_task_headers(struct iscsi_task *task,
 184			     struct iser_tx_desc *tx_desc)
 185{
 186	struct iser_conn *iser_conn = task->conn->dd_data;
 187	struct iser_device *device = iser_conn->ib_conn.device;
 188	struct iscsi_iser_task *iser_task = task->dd_data;
 189	u64 dma_addr;
 190	const bool mgmt_task = !task->sc && !in_interrupt();
 191	int ret = 0;
 192
 193	if (unlikely(mgmt_task))
 194		mutex_lock(&iser_conn->state_mutex);
 195
 196	if (unlikely(iser_conn->state != ISER_CONN_UP)) {
 197		ret = -ENODEV;
 198		goto out;
 199	}
 200
 201	dma_addr = ib_dma_map_single(device->ib_device, (void *)tx_desc,
 202				ISER_HEADERS_LEN, DMA_TO_DEVICE);
 203	if (ib_dma_mapping_error(device->ib_device, dma_addr)) {
 204		ret = -ENOMEM;
 205		goto out;
 206	}
 207
 208	tx_desc->wr_idx = 0;
 
 209	tx_desc->mapped = true;
 210	tx_desc->dma_addr = dma_addr;
 211	tx_desc->tx_sg[0].addr   = tx_desc->dma_addr;
 212	tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
 213	tx_desc->tx_sg[0].lkey   = device->pd->local_dma_lkey;
 214
 215	iser_task->iser_conn = iser_conn;
 216out:
 217	if (unlikely(mgmt_task))
 218		mutex_unlock(&iser_conn->state_mutex);
 219
 220	return ret;
 221}
 222
 223/**
 224 * iscsi_iser_task_init() - Initialize iscsi-iser task
 225 * @task: iscsi task
 226 *
 227 * Initialize the task for the scsi command or mgmt command.
 228 *
 229 * Return: Returns zero on success or -ENOMEM when failing
 230 *         to init task headers (dma mapping error).
 231 */
 232static int
 233iscsi_iser_task_init(struct iscsi_task *task)
 234{
 235	struct iscsi_iser_task *iser_task = task->dd_data;
 236	int ret;
 237
 238	ret = iser_initialize_task_headers(task, &iser_task->desc);
 239	if (ret) {
 240		iser_err("Failed to init task %p, err = %d\n",
 241			 iser_task, ret);
 242		return ret;
 243	}
 244
 245	/* mgmt task */
 246	if (!task->sc)
 247		return 0;
 248
 249	iser_task->command_sent = 0;
 250	iser_task_rdma_init(iser_task);
 251	iser_task->sc = task->sc;
 252
 253	return 0;
 254}
 255
 256/**
 257 * iscsi_iser_mtask_xmit() - xmit management (immediate) task
 258 * @conn: iscsi connection
 259 * @task: task management task
 260 *
 261 * Notes:
 262 *	The function can return -EAGAIN in which case caller must
 263 *	call it again later, or recover. '0' return code means successful
 264 *	xmit.
 265 *
 266 **/
 267static int
 268iscsi_iser_mtask_xmit(struct iscsi_conn *conn, struct iscsi_task *task)
 269{
 270	int error = 0;
 271
 272	iser_dbg("mtask xmit [cid %d itt 0x%x]\n", conn->id, task->itt);
 273
 274	error = iser_send_control(conn, task);
 275
 276	/* since iser xmits control with zero copy, tasks can not be recycled
 277	 * right after sending them.
 278	 * The recycling scheme is based on whether a response is expected
 279	 * - if yes, the task is recycled at iscsi_complete_pdu
 280	 * - if no,  the task is recycled at iser_snd_completion
 281	 */
 282	return error;
 283}
 284
 285static int
 286iscsi_iser_task_xmit_unsol_data(struct iscsi_conn *conn,
 287				 struct iscsi_task *task)
 288{
 289	struct iscsi_r2t_info *r2t = &task->unsol_r2t;
 290	struct iscsi_data hdr;
 291	int error = 0;
 292
 293	/* Send data-out PDUs while there's still unsolicited data to send */
 294	while (iscsi_task_has_unsol_data(task)) {
 295		iscsi_prep_data_out_pdu(task, r2t, &hdr);
 296		iser_dbg("Sending data-out: itt 0x%x, data count %d\n",
 297			   hdr.itt, r2t->data_count);
 298
 299		/* the buffer description has been passed with the command */
 300		/* Send the command */
 301		error = iser_send_data_out(conn, task, &hdr);
 302		if (error) {
 303			r2t->datasn--;
 304			goto iscsi_iser_task_xmit_unsol_data_exit;
 305		}
 306		r2t->sent += r2t->data_count;
 307		iser_dbg("Need to send %d more as data-out PDUs\n",
 308			   r2t->data_length - r2t->sent);
 309	}
 310
 311iscsi_iser_task_xmit_unsol_data_exit:
 312	return error;
 313}
 314
 315/**
 316 * iscsi_iser_task_xmit() - xmit iscsi-iser task
 317 * @task: iscsi task
 318 *
 319 * Return: zero on success or escalates $error on failure.
 320 */
 321static int
 322iscsi_iser_task_xmit(struct iscsi_task *task)
 323{
 324	struct iscsi_conn *conn = task->conn;
 325	struct iscsi_iser_task *iser_task = task->dd_data;
 326	int error = 0;
 327
 328	if (!task->sc)
 329		return iscsi_iser_mtask_xmit(conn, task);
 330
 331	if (task->sc->sc_data_direction == DMA_TO_DEVICE) {
 332		BUG_ON(scsi_bufflen(task->sc) == 0);
 333
 334		iser_dbg("cmd [itt %x total %d imm %d unsol_data %d\n",
 335			   task->itt, scsi_bufflen(task->sc),
 336			   task->imm_count, task->unsol_r2t.data_length);
 337	}
 338
 339	iser_dbg("ctask xmit [cid %d itt 0x%x]\n",
 340		   conn->id, task->itt);
 341
 342	/* Send the cmd PDU */
 343	if (!iser_task->command_sent) {
 344		error = iser_send_command(conn, task);
 345		if (error)
 346			goto iscsi_iser_task_xmit_exit;
 347		iser_task->command_sent = 1;
 348	}
 349
 350	/* Send unsolicited data-out PDU(s) if necessary */
 351	if (iscsi_task_has_unsol_data(task))
 352		error = iscsi_iser_task_xmit_unsol_data(conn, task);
 353
 354 iscsi_iser_task_xmit_exit:
 355	return error;
 356}
 357
 358/**
 359 * iscsi_iser_cleanup_task() - cleanup an iscsi-iser task
 360 * @task: iscsi task
 361 *
 362 * Notes: In case the RDMA device is already NULL (might have
 363 *        been removed in DEVICE_REMOVAL CM event it will bail-out
 364 *        without doing dma unmapping.
 365 */
 366static void iscsi_iser_cleanup_task(struct iscsi_task *task)
 367{
 368	struct iscsi_iser_task *iser_task = task->dd_data;
 369	struct iser_tx_desc *tx_desc = &iser_task->desc;
 370	struct iser_conn *iser_conn = task->conn->dd_data;
 371	struct iser_device *device = iser_conn->ib_conn.device;
 372
 373	/* DEVICE_REMOVAL event might have already released the device */
 374	if (!device)
 375		return;
 376
 377	if (likely(tx_desc->mapped)) {
 378		ib_dma_unmap_single(device->ib_device, tx_desc->dma_addr,
 379				    ISER_HEADERS_LEN, DMA_TO_DEVICE);
 380		tx_desc->mapped = false;
 381	}
 382
 383	/* mgmt tasks do not need special cleanup */
 384	if (!task->sc)
 385		return;
 386
 387	if (iser_task->status == ISER_TASK_STATUS_STARTED) {
 388		iser_task->status = ISER_TASK_STATUS_COMPLETED;
 389		iser_task_rdma_finalize(iser_task);
 390	}
 391}
 392
 393/**
 394 * iscsi_iser_check_protection() - check protection information status of task.
 395 * @task:     iscsi task
 396 * @sector:   error sector if exsists (output)
 397 *
 398 * Return: zero if no data-integrity errors have occured
 399 *         0x1: data-integrity error occured in the guard-block
 400 *         0x2: data-integrity error occured in the reference tag
 401 *         0x3: data-integrity error occured in the application tag
 402 *
 403 *         In addition the error sector is marked.
 404 */
 405static u8
 406iscsi_iser_check_protection(struct iscsi_task *task, sector_t *sector)
 407{
 408	struct iscsi_iser_task *iser_task = task->dd_data;
 
 
 409
 410	if (iser_task->dir[ISER_DIR_IN])
 411		return iser_check_task_pi_status(iser_task, ISER_DIR_IN,
 412						 sector);
 413	else
 414		return iser_check_task_pi_status(iser_task, ISER_DIR_OUT,
 415						 sector);
 416}
 417
 418/**
 419 * iscsi_iser_conn_create() - create a new iscsi-iser connection
 420 * @cls_session: iscsi class connection
 421 * @conn_idx:    connection index within the session (for MCS)
 422 *
 423 * Return: iscsi_cls_conn when iscsi_conn_setup succeeds or NULL
 424 *         otherwise.
 425 */
 426static struct iscsi_cls_conn *
 427iscsi_iser_conn_create(struct iscsi_cls_session *cls_session,
 428		       uint32_t conn_idx)
 429{
 430	struct iscsi_conn *conn;
 431	struct iscsi_cls_conn *cls_conn;
 432
 433	cls_conn = iscsi_conn_setup(cls_session, 0, conn_idx);
 434	if (!cls_conn)
 435		return NULL;
 436	conn = cls_conn->dd_data;
 437
 438	/*
 439	 * due to issues with the login code re iser sematics
 440	 * this not set in iscsi_conn_setup - FIXME
 441	 */
 442	conn->max_recv_dlength = ISER_RECV_DATA_SEG_LEN;
 443
 444	return cls_conn;
 445}
 446
 447/**
 448 * iscsi_iser_conn_bind() - bind iscsi and iser connection structures
 449 * @cls_session:     iscsi class session
 450 * @cls_conn:        iscsi class connection
 451 * @transport_eph:   transport end-point handle
 452 * @is_leading:      indicate if this is the session leading connection (MCS)
 453 *
 454 * Return: zero on success, $error if iscsi_conn_bind fails and
 455 *         -EINVAL in case end-point doesn't exsits anymore or iser connection
 456 *         state is not UP (teardown already started).
 457 */
 458static int
 459iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session,
 460		     struct iscsi_cls_conn *cls_conn,
 461		     uint64_t transport_eph,
 462		     int is_leading)
 463{
 464	struct iscsi_conn *conn = cls_conn->dd_data;
 465	struct iser_conn *iser_conn;
 466	struct iscsi_endpoint *ep;
 467	int error;
 468
 469	error = iscsi_conn_bind(cls_session, cls_conn, is_leading);
 470	if (error)
 471		return error;
 472
 473	/* the transport ep handle comes from user space so it must be
 474	 * verified against the global ib connections list */
 475	ep = iscsi_lookup_endpoint(transport_eph);
 476	if (!ep) {
 477		iser_err("can't bind eph %llx\n",
 478			 (unsigned long long)transport_eph);
 479		return -EINVAL;
 480	}
 481	iser_conn = ep->dd_data;
 482
 483	mutex_lock(&iser_conn->state_mutex);
 484	if (iser_conn->state != ISER_CONN_UP) {
 485		error = -EINVAL;
 486		iser_err("iser_conn %p state is %d, teardown started\n",
 487			 iser_conn, iser_conn->state);
 488		goto out;
 489	}
 490
 491	error = iser_alloc_rx_descriptors(iser_conn, conn->session);
 492	if (error)
 493		goto out;
 494
 495	/* binds the iSER connection retrieved from the previously
 496	 * connected ep_handle to the iSCSI layer connection. exchanges
 497	 * connection pointers */
 498	iser_info("binding iscsi conn %p to iser_conn %p\n", conn, iser_conn);
 499
 500	conn->dd_data = iser_conn;
 501	iser_conn->iscsi_conn = conn;
 502
 503out:
 
 504	mutex_unlock(&iser_conn->state_mutex);
 505	return error;
 506}
 507
 508/**
 509 * iscsi_iser_conn_start() - start iscsi-iser connection
 510 * @cls_conn: iscsi class connection
 511 *
 512 * Notes: Here iser intialize (or re-initialize) stop_completion as
 513 *        from this point iscsi must call conn_stop in session/connection
 514 *        teardown so iser transport must wait for it.
 515 */
 516static int
 517iscsi_iser_conn_start(struct iscsi_cls_conn *cls_conn)
 518{
 519	struct iscsi_conn *iscsi_conn;
 520	struct iser_conn *iser_conn;
 521
 522	iscsi_conn = cls_conn->dd_data;
 523	iser_conn = iscsi_conn->dd_data;
 524	reinit_completion(&iser_conn->stop_completion);
 525
 526	return iscsi_conn_start(cls_conn);
 527}
 528
 529/**
 530 * iscsi_iser_conn_stop() - stop iscsi-iser connection
 531 * @cls_conn:  iscsi class connection
 532 * @flag:      indicate if recover or terminate (passed as is)
 533 *
 534 * Notes: Calling iscsi_conn_stop might theoretically race with
 535 *        DEVICE_REMOVAL event and dereference a previously freed RDMA device
 536 *        handle, so we call it under iser the state lock to protect against
 537 *        this kind of race.
 538 */
 539static void
 540iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
 541{
 542	struct iscsi_conn *conn = cls_conn->dd_data;
 543	struct iser_conn *iser_conn = conn->dd_data;
 544
 545	iser_info("stopping iscsi_conn: %p, iser_conn: %p\n", conn, iser_conn);
 546
 547	/*
 548	 * Userspace may have goofed up and not bound the connection or
 549	 * might have only partially setup the connection.
 550	 */
 551	if (iser_conn) {
 552		mutex_lock(&iser_conn->state_mutex);
 
 553		iser_conn_terminate(iser_conn);
 554		iscsi_conn_stop(cls_conn, flag);
 555
 556		/* unbind */
 557		iser_conn->iscsi_conn = NULL;
 558		conn->dd_data = NULL;
 
 559
 560		complete(&iser_conn->stop_completion);
 561		mutex_unlock(&iser_conn->state_mutex);
 562	} else {
 563		iscsi_conn_stop(cls_conn, flag);
 564	}
 565}
 566
 567/**
 568 * iscsi_iser_session_destroy() - destroy iscsi-iser session
 569 * @cls_session: iscsi class session
 570 *
 571 * Removes and free iscsi host.
 572 */
 573static void
 574iscsi_iser_session_destroy(struct iscsi_cls_session *cls_session)
 575{
 576	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
 577
 578	iscsi_session_teardown(cls_session);
 579	iscsi_host_remove(shost);
 580	iscsi_host_free(shost);
 581}
 582
 583static inline unsigned int
 584iser_dif_prot_caps(int prot_caps)
 585{
 586	return ((prot_caps & IB_PROT_T10DIF_TYPE_1) ?
 587		SHOST_DIF_TYPE1_PROTECTION | SHOST_DIX_TYPE0_PROTECTION |
 588		SHOST_DIX_TYPE1_PROTECTION : 0) |
 589	       ((prot_caps & IB_PROT_T10DIF_TYPE_2) ?
 590		SHOST_DIF_TYPE2_PROTECTION | SHOST_DIX_TYPE2_PROTECTION : 0) |
 591	       ((prot_caps & IB_PROT_T10DIF_TYPE_3) ?
 592		SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE3_PROTECTION : 0);
 
 
 
 
 
 
 
 593}
 594
 595/**
 596 * iscsi_iser_session_create() - create an iscsi-iser session
 597 * @ep:             iscsi end-point handle
 598 * @cmds_max:       maximum commands in this session
 599 * @qdepth:         session command queue depth
 600 * @initial_cmdsn:  initiator command sequnce number
 601 *
 602 * Allocates and adds a scsi host, expose DIF supprot if
 603 * exists, and sets up an iscsi session.
 604 */
 605static struct iscsi_cls_session *
 606iscsi_iser_session_create(struct iscsi_endpoint *ep,
 607			  uint16_t cmds_max, uint16_t qdepth,
 608			  uint32_t initial_cmdsn)
 609{
 610	struct iscsi_cls_session *cls_session;
 611	struct iscsi_session *session;
 612	struct Scsi_Host *shost;
 613	struct iser_conn *iser_conn = NULL;
 614	struct ib_conn *ib_conn;
 
 615	u32 max_fr_sectors;
 616	u16 max_cmds;
 617
 618	shost = iscsi_host_alloc(&iscsi_iser_sht, 0, 0);
 619	if (!shost)
 620		return NULL;
 621	shost->transportt = iscsi_iser_scsi_transport;
 622	shost->cmd_per_lun = qdepth;
 623	shost->max_lun = iscsi_max_lun;
 624	shost->max_id = 0;
 625	shost->max_channel = 0;
 626	shost->max_cmd_len = 16;
 627
 628	/*
 629	 * older userspace tools (before 2.0-870) did not pass us
 630	 * the leading conn's ep so this will be NULL;
 631	 */
 632	if (ep) {
 633		iser_conn = ep->dd_data;
 634		max_cmds = iser_conn->max_cmds;
 635		shost->sg_tablesize = iser_conn->scsi_sg_tablesize;
 
 636
 637		mutex_lock(&iser_conn->state_mutex);
 638		if (iser_conn->state != ISER_CONN_UP) {
 639			iser_err("iser conn %p already started teardown\n",
 640				 iser_conn);
 641			mutex_unlock(&iser_conn->state_mutex);
 642			goto free_host;
 643		}
 644
 645		ib_conn = &iser_conn->ib_conn;
 
 646		if (ib_conn->pi_support) {
 647			u32 sig_caps = ib_conn->device->ib_device->attrs.sig_prot_cap;
 648
 
 649			scsi_host_set_prot(shost, iser_dif_prot_caps(sig_caps));
 650			scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP |
 651						   SHOST_DIX_GUARD_CRC);
 652		}
 653
 654		/*
 655		 * Limit the sg_tablesize and max_sectors based on the device
 656		 * max fastreg page list length.
 657		 */
 658		shost->sg_tablesize = min_t(unsigned short, shost->sg_tablesize,
 659			ib_conn->device->ib_device->attrs.max_fast_reg_page_list_len);
 660
 661		if (iscsi_host_add(shost,
 662				   ib_conn->device->ib_device->dma_device)) {
 663			mutex_unlock(&iser_conn->state_mutex);
 664			goto free_host;
 665		}
 666		mutex_unlock(&iser_conn->state_mutex);
 667	} else {
 668		max_cmds = ISER_DEF_XMIT_CMDS_MAX;
 669		if (iscsi_host_add(shost, NULL))
 670			goto free_host;
 671	}
 672
 673	/*
 674	 * FRs or FMRs can only map up to a (device) page per entry, but if the
 675	 * first entry is misaligned we'll end up using using two entries
 676	 * (head and tail) for a single page worth data, so we have to drop
 677	 * one segment from the calculation.
 678	 */
 679	max_fr_sectors = ((shost->sg_tablesize - 1) * PAGE_SIZE) >> 9;
 680	shost->max_sectors = min(iser_max_sectors, max_fr_sectors);
 681
 682	if (cmds_max > max_cmds) {
 683		iser_info("cmds_max changed from %u to %u\n",
 684			  cmds_max, max_cmds);
 685		cmds_max = max_cmds;
 686	}
 
 
 687
 688	cls_session = iscsi_session_setup(&iscsi_iser_transport, shost,
 689					  cmds_max, 0,
 690					  sizeof(struct iscsi_iser_task),
 691					  initial_cmdsn, 0);
 692	if (!cls_session)
 693		goto remove_host;
 694	session = cls_session->dd_data;
 695
 696	shost->can_queue = session->scsi_cmds_max;
 697	return cls_session;
 698
 699remove_host:
 700	iscsi_host_remove(shost);
 701free_host:
 702	iscsi_host_free(shost);
 703	return NULL;
 704}
 705
 706static int
 707iscsi_iser_set_param(struct iscsi_cls_conn *cls_conn,
 708		     enum iscsi_param param, char *buf, int buflen)
 709{
 710	int value;
 711
 712	switch (param) {
 713	case ISCSI_PARAM_MAX_RECV_DLENGTH:
 714		/* TBD */
 715		break;
 716	case ISCSI_PARAM_HDRDGST_EN:
 717		sscanf(buf, "%d", &value);
 718		if (value) {
 719			iser_err("DataDigest wasn't negotiated to None\n");
 720			return -EPROTO;
 721		}
 722		break;
 723	case ISCSI_PARAM_DATADGST_EN:
 724		sscanf(buf, "%d", &value);
 725		if (value) {
 726			iser_err("DataDigest wasn't negotiated to None\n");
 727			return -EPROTO;
 728		}
 729		break;
 730	case ISCSI_PARAM_IFMARKER_EN:
 731		sscanf(buf, "%d", &value);
 732		if (value) {
 733			iser_err("IFMarker wasn't negotiated to No\n");
 734			return -EPROTO;
 735		}
 736		break;
 737	case ISCSI_PARAM_OFMARKER_EN:
 738		sscanf(buf, "%d", &value);
 739		if (value) {
 740			iser_err("OFMarker wasn't negotiated to No\n");
 741			return -EPROTO;
 742		}
 743		break;
 744	default:
 745		return iscsi_set_param(cls_conn, param, buf, buflen);
 746	}
 747
 748	return 0;
 749}
 750
 751/**
 752 * iscsi_iser_set_param() - set class connection parameter
 753 * @cls_conn:    iscsi class connection
 754 * @stats:       iscsi stats to output
 755 *
 756 * Output connection statistics.
 757 */
 758static void
 759iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
 760{
 761	struct iscsi_conn *conn = cls_conn->dd_data;
 762
 763	stats->txdata_octets = conn->txdata_octets;
 764	stats->rxdata_octets = conn->rxdata_octets;
 765	stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
 766	stats->dataout_pdus = conn->dataout_pdus_cnt;
 767	stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
 768	stats->datain_pdus = conn->datain_pdus_cnt; /* always 0 */
 769	stats->r2t_pdus = conn->r2t_pdus_cnt; /* always 0 */
 770	stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
 771	stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
 772	stats->custom_length = 0;
 773}
 774
 775static int iscsi_iser_get_ep_param(struct iscsi_endpoint *ep,
 776				   enum iscsi_param param, char *buf)
 777{
 778	struct iser_conn *iser_conn = ep->dd_data;
 779	int len;
 780
 781	switch (param) {
 782	case ISCSI_PARAM_CONN_PORT:
 783	case ISCSI_PARAM_CONN_ADDRESS:
 784		if (!iser_conn || !iser_conn->ib_conn.cma_id)
 785			return -ENOTCONN;
 786
 787		return iscsi_conn_get_addr_param((struct sockaddr_storage *)
 788				&iser_conn->ib_conn.cma_id->route.addr.dst_addr,
 789				param, buf);
 
 790		break;
 791	default:
 792		return -ENOSYS;
 793	}
 794
 795	return len;
 796}
 797
 798/**
 799 * iscsi_iser_ep_connect() - Initiate iSER connection establishment
 800 * @shost:          scsi_host
 801 * @dst_addr:       destination address
 802 * @non-blocking:   indicate if routine can block
 803 *
 804 * Allocate an iscsi endpoint, an iser_conn structure and bind them.
 805 * After that start RDMA connection establishment via rdma_cm. We
 806 * don't allocate iser_conn embedded in iscsi_endpoint since in teardown
 807 * the endpoint will be destroyed at ep_disconnect while iser_conn will
 808 * cleanup its resources asynchronuously.
 809 *
 810 * Return: iscsi_endpoint created by iscsi layer or ERR_PTR(error)
 811 *         if fails.
 812 */
 813static struct iscsi_endpoint *
 814iscsi_iser_ep_connect(struct Scsi_Host *shost, struct sockaddr *dst_addr,
 815		      int non_blocking)
 816{
 817	int err;
 818	struct iser_conn *iser_conn;
 819	struct iscsi_endpoint *ep;
 820
 821	ep = iscsi_create_endpoint(0);
 822	if (!ep)
 823		return ERR_PTR(-ENOMEM);
 824
 825	iser_conn = kzalloc(sizeof(*iser_conn), GFP_KERNEL);
 826	if (!iser_conn) {
 827		err = -ENOMEM;
 828		goto failure;
 829	}
 830
 831	ep->dd_data = iser_conn;
 832	iser_conn->ep = ep;
 833	iser_conn_init(iser_conn);
 834
 835	err = iser_connect(iser_conn, NULL, dst_addr, non_blocking);
 836	if (err)
 837		goto failure;
 838
 839	return ep;
 840failure:
 841	iscsi_destroy_endpoint(ep);
 842	return ERR_PTR(err);
 843}
 844
 845/**
 846 * iscsi_iser_ep_poll() - poll for iser connection establishment to complete
 847 * @ep:            iscsi endpoint (created at ep_connect)
 848 * @timeout_ms:    polling timeout allowed in ms.
 849 *
 850 * This routine boils down to waiting for up_completion signaling
 851 * that cma_id got CONNECTED event.
 852 *
 853 * Return: 1 if succeeded in connection establishment, 0 if timeout expired
 854 *         (libiscsi will retry will kick in) or -1 if interrupted by signal
 855 *         or more likely iser connection state transitioned to TEMINATING or
 856 *         DOWN during the wait period.
 857 */
 858static int
 859iscsi_iser_ep_poll(struct iscsi_endpoint *ep, int timeout_ms)
 860{
 861	struct iser_conn *iser_conn = ep->dd_data;
 862	int rc;
 863
 864	rc = wait_for_completion_interruptible_timeout(&iser_conn->up_completion,
 865						       msecs_to_jiffies(timeout_ms));
 866	/* if conn establishment failed, return error code to iscsi */
 867	if (rc == 0) {
 868		mutex_lock(&iser_conn->state_mutex);
 869		if (iser_conn->state == ISER_CONN_TERMINATING ||
 870		    iser_conn->state == ISER_CONN_DOWN)
 871			rc = -1;
 872		mutex_unlock(&iser_conn->state_mutex);
 873	}
 874
 875	iser_info("iser conn %p rc = %d\n", iser_conn, rc);
 876
 877	if (rc > 0)
 878		return 1; /* success, this is the equivalent of POLLOUT */
 879	else if (!rc)
 880		return 0; /* timeout */
 881	else
 882		return rc; /* signal */
 883}
 884
 885/**
 886 * iscsi_iser_ep_disconnect() - Initiate connection teardown process
 887 * @ep:    iscsi endpoint handle
 888 *
 889 * This routine is not blocked by iser and RDMA termination process
 890 * completion as we queue a deffered work for iser/RDMA destruction
 891 * and cleanup or actually call it immediately in case we didn't pass
 892 * iscsi conn bind/start stage, thus it is safe.
 893 */
 894static void
 895iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep)
 896{
 897	struct iser_conn *iser_conn = ep->dd_data;
 898
 899	iser_info("ep %p iser conn %p\n", ep, iser_conn);
 900
 901	mutex_lock(&iser_conn->state_mutex);
 902	iser_conn_terminate(iser_conn);
 903
 904	/*
 905	 * if iser_conn and iscsi_conn are bound, we must wait for
 906	 * iscsi_conn_stop and flush errors completion before freeing
 907	 * the iser resources. Otherwise we are safe to free resources
 908	 * immediately.
 909	 */
 910	if (iser_conn->iscsi_conn) {
 911		INIT_WORK(&iser_conn->release_work, iser_release_work);
 912		queue_work(release_wq, &iser_conn->release_work);
 913		mutex_unlock(&iser_conn->state_mutex);
 914	} else {
 915		iser_conn->state = ISER_CONN_DOWN;
 916		mutex_unlock(&iser_conn->state_mutex);
 917		iser_conn_release(iser_conn);
 918	}
 919
 920	iscsi_destroy_endpoint(ep);
 921}
 922
 923static umode_t iser_attr_is_visible(int param_type, int param)
 924{
 925	switch (param_type) {
 926	case ISCSI_HOST_PARAM:
 927		switch (param) {
 928		case ISCSI_HOST_PARAM_NETDEV_NAME:
 929		case ISCSI_HOST_PARAM_HWADDRESS:
 930		case ISCSI_HOST_PARAM_INITIATOR_NAME:
 931			return S_IRUGO;
 932		default:
 933			return 0;
 934		}
 935	case ISCSI_PARAM:
 936		switch (param) {
 937		case ISCSI_PARAM_MAX_RECV_DLENGTH:
 938		case ISCSI_PARAM_MAX_XMIT_DLENGTH:
 939		case ISCSI_PARAM_HDRDGST_EN:
 940		case ISCSI_PARAM_DATADGST_EN:
 941		case ISCSI_PARAM_CONN_ADDRESS:
 942		case ISCSI_PARAM_CONN_PORT:
 943		case ISCSI_PARAM_EXP_STATSN:
 944		case ISCSI_PARAM_PERSISTENT_ADDRESS:
 945		case ISCSI_PARAM_PERSISTENT_PORT:
 946		case ISCSI_PARAM_PING_TMO:
 947		case ISCSI_PARAM_RECV_TMO:
 948		case ISCSI_PARAM_INITIAL_R2T_EN:
 949		case ISCSI_PARAM_MAX_R2T:
 950		case ISCSI_PARAM_IMM_DATA_EN:
 951		case ISCSI_PARAM_FIRST_BURST:
 952		case ISCSI_PARAM_MAX_BURST:
 953		case ISCSI_PARAM_PDU_INORDER_EN:
 954		case ISCSI_PARAM_DATASEQ_INORDER_EN:
 955		case ISCSI_PARAM_TARGET_NAME:
 956		case ISCSI_PARAM_TPGT:
 957		case ISCSI_PARAM_USERNAME:
 958		case ISCSI_PARAM_PASSWORD:
 959		case ISCSI_PARAM_USERNAME_IN:
 960		case ISCSI_PARAM_PASSWORD_IN:
 961		case ISCSI_PARAM_FAST_ABORT:
 962		case ISCSI_PARAM_ABORT_TMO:
 963		case ISCSI_PARAM_LU_RESET_TMO:
 964		case ISCSI_PARAM_TGT_RESET_TMO:
 965		case ISCSI_PARAM_IFACE_NAME:
 966		case ISCSI_PARAM_INITIATOR_NAME:
 967		case ISCSI_PARAM_DISCOVERY_SESS:
 968			return S_IRUGO;
 969		default:
 970			return 0;
 971		}
 972	}
 973
 974	return 0;
 975}
 976
 977static int iscsi_iser_slave_alloc(struct scsi_device *sdev)
 978{
 979	struct iscsi_session *session;
 980	struct iser_conn *iser_conn;
 981	struct ib_device *ib_dev;
 982
 983	session = starget_to_session(scsi_target(sdev))->dd_data;
 984	iser_conn = session->leadconn->dd_data;
 985	ib_dev = iser_conn->ib_conn.device->ib_device;
 986
 987	if (!(ib_dev->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG))
 988		blk_queue_virt_boundary(sdev->request_queue, ~MASK_4K);
 989
 990	return 0;
 991}
 992
 993static struct scsi_host_template iscsi_iser_sht = {
 994	.module                 = THIS_MODULE,
 995	.name                   = "iSCSI Initiator over iSER",
 996	.queuecommand           = iscsi_queuecommand,
 997	.change_queue_depth	= scsi_change_queue_depth,
 998	.sg_tablesize           = ISCSI_ISER_DEF_SG_TABLESIZE,
 999	.cmd_per_lun            = ISER_DEF_CMD_PER_LUN,
 
1000	.eh_abort_handler       = iscsi_eh_abort,
1001	.eh_device_reset_handler= iscsi_eh_device_reset,
1002	.eh_target_reset_handler = iscsi_eh_recover_target,
1003	.target_alloc		= iscsi_target_alloc,
1004	.use_clustering         = ENABLE_CLUSTERING,
1005	.slave_alloc            = iscsi_iser_slave_alloc,
1006	.proc_name              = "iscsi_iser",
1007	.this_id                = -1,
1008	.track_queue_depth	= 1,
 
1009};
1010
1011static struct iscsi_transport iscsi_iser_transport = {
1012	.owner                  = THIS_MODULE,
1013	.name                   = "iser",
1014	.caps                   = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_TEXT_NEGO,
1015	/* session management */
1016	.create_session         = iscsi_iser_session_create,
1017	.destroy_session        = iscsi_iser_session_destroy,
1018	/* connection management */
1019	.create_conn            = iscsi_iser_conn_create,
1020	.bind_conn              = iscsi_iser_conn_bind,
 
1021	.destroy_conn           = iscsi_conn_teardown,
1022	.attr_is_visible	= iser_attr_is_visible,
1023	.set_param              = iscsi_iser_set_param,
1024	.get_conn_param		= iscsi_conn_get_param,
1025	.get_ep_param		= iscsi_iser_get_ep_param,
1026	.get_session_param	= iscsi_session_get_param,
1027	.start_conn             = iscsi_iser_conn_start,
1028	.stop_conn              = iscsi_iser_conn_stop,
1029	/* iscsi host params */
1030	.get_host_param		= iscsi_host_get_param,
1031	.set_host_param		= iscsi_host_set_param,
1032	/* IO */
1033	.send_pdu		= iscsi_conn_send_pdu,
1034	.get_stats		= iscsi_iser_conn_get_stats,
1035	.init_task		= iscsi_iser_task_init,
1036	.xmit_task		= iscsi_iser_task_xmit,
1037	.cleanup_task		= iscsi_iser_cleanup_task,
1038	.alloc_pdu		= iscsi_iser_pdu_alloc,
1039	.check_protection	= iscsi_iser_check_protection,
1040	/* recovery */
1041	.session_recovery_timedout = iscsi_session_recovery_timedout,
1042
1043	.ep_connect             = iscsi_iser_ep_connect,
1044	.ep_poll                = iscsi_iser_ep_poll,
1045	.ep_disconnect          = iscsi_iser_ep_disconnect
1046};
1047
1048static int __init iser_init(void)
1049{
1050	int err;
1051
1052	iser_dbg("Starting iSER datamover...\n");
1053
1054	if (iscsi_max_lun < 1) {
1055		iser_err("Invalid max_lun value of %u\n", iscsi_max_lun);
1056		return -EINVAL;
1057	}
1058
1059	memset(&ig, 0, sizeof(struct iser_global));
1060
1061	ig.desc_cache = kmem_cache_create("iser_descriptors",
1062					  sizeof(struct iser_tx_desc),
1063					  0, SLAB_HWCACHE_ALIGN,
1064					  NULL);
1065	if (ig.desc_cache == NULL)
1066		return -ENOMEM;
1067
1068	/* device init is called only after the first addr resolution */
1069	mutex_init(&ig.device_list_mutex);
1070	INIT_LIST_HEAD(&ig.device_list);
1071	mutex_init(&ig.connlist_mutex);
1072	INIT_LIST_HEAD(&ig.connlist);
1073
1074	release_wq = alloc_workqueue("release workqueue", 0, 0);
1075	if (!release_wq) {
1076		iser_err("failed to allocate release workqueue\n");
1077		err = -ENOMEM;
1078		goto err_alloc_wq;
1079	}
1080
1081	iscsi_iser_scsi_transport = iscsi_register_transport(
1082							&iscsi_iser_transport);
1083	if (!iscsi_iser_scsi_transport) {
1084		iser_err("iscsi_register_transport failed\n");
1085		err = -EINVAL;
1086		goto err_reg;
1087	}
1088
1089	return 0;
1090
1091err_reg:
1092	destroy_workqueue(release_wq);
1093err_alloc_wq:
1094	kmem_cache_destroy(ig.desc_cache);
1095
1096	return err;
1097}
1098
1099static void __exit iser_exit(void)
1100{
1101	struct iser_conn *iser_conn, *n;
1102	int connlist_empty;
1103
1104	iser_dbg("Removing iSER datamover...\n");
1105	destroy_workqueue(release_wq);
1106
1107	mutex_lock(&ig.connlist_mutex);
1108	connlist_empty = list_empty(&ig.connlist);
1109	mutex_unlock(&ig.connlist_mutex);
1110
1111	if (!connlist_empty) {
1112		iser_err("Error cleanup stage completed but we still have iser "
1113			 "connections, destroying them anyway\n");
1114		list_for_each_entry_safe(iser_conn, n, &ig.connlist,
1115					 conn_list) {
1116			iser_conn_release(iser_conn);
1117		}
1118	}
1119
1120	iscsi_unregister_transport(&iscsi_iser_transport);
1121	kmem_cache_destroy(ig.desc_cache);
1122}
1123
1124module_init(iser_init);
1125module_exit(iser_exit);