xref: /linux/drivers/infiniband/ulp/iser/iscsi_iser.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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  * maintained by openib-general@openib.org
9  *
10  * This software is available to you under a choice of one of two
11  * licenses.  You may choose to be licensed under the terms of the GNU
12  * General Public License (GPL) Version 2, available from the file
13  * COPYING in the main directory of this source tree, or the
14  * OpenIB.org BSD license below:
15  *
16  *     Redistribution and use in source and binary forms, with or
17  *     without modification, are permitted provided that the following
18  *     conditions are met:
19  *
20  *	- Redistributions of source code must retain the above
21  *	  copyright notice, this list of conditions and the following
22  *	  disclaimer.
23  *
24  *	- Redistributions in binary form must reproduce the above
25  *	  copyright notice, this list of conditions and the following
26  *	  disclaimer in the documentation and/or other materials
27  *	  provided with the distribution.
28  *
29  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
30  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
31  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
32  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
33  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
34  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
35  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
36  * SOFTWARE.
37  *
38  * Credits:
39  *	Christoph Hellwig
40  *	FUJITA Tomonori
41  *	Arne Redlich
42  *	Zhenyu Wang
43  * Modified by:
44  *      Erez Zilber
45  */
46 
47 #include <linux/types.h>
48 #include <linux/list.h>
49 #include <linux/hardirq.h>
50 #include <linux/kfifo.h>
51 #include <linux/blkdev.h>
52 #include <linux/init.h>
53 #include <linux/ioctl.h>
54 #include <linux/cdev.h>
55 #include <linux/in.h>
56 #include <linux/net.h>
57 #include <linux/scatterlist.h>
58 #include <linux/delay.h>
59 #include <linux/slab.h>
60 #include <linux/module.h>
61 
62 #include <net/sock.h>
63 
64 #include <asm/uaccess.h>
65 
66 #include <scsi/scsi_cmnd.h>
67 #include <scsi/scsi_device.h>
68 #include <scsi/scsi_eh.h>
69 #include <scsi/scsi_tcq.h>
70 #include <scsi/scsi_host.h>
71 #include <scsi/scsi.h>
72 #include <scsi/scsi_transport_iscsi.h>
73 
74 #include "iscsi_iser.h"
75 
76 static struct scsi_host_template iscsi_iser_sht;
77 static struct iscsi_transport iscsi_iser_transport;
78 static struct scsi_transport_template *iscsi_iser_scsi_transport;
79 
80 static unsigned int iscsi_max_lun = 512;
81 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
82 
83 int iser_debug_level = 0;
84 
85 MODULE_DESCRIPTION("iSER (iSCSI Extensions for RDMA) Datamover "
86 		   "v" DRV_VER " (" DRV_DATE ")");
87 MODULE_LICENSE("Dual BSD/GPL");
88 MODULE_AUTHOR("Alex Nezhinsky, Dan Bar Dov, Or Gerlitz");
89 
90 module_param_named(debug_level, iser_debug_level, int, 0644);
91 MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:disabled)");
92 
93 struct iser_global ig;
94 
95 void
96 iscsi_iser_recv(struct iscsi_conn *conn,
97 		struct iscsi_hdr *hdr, char *rx_data, int rx_data_len)
98 {
99 	int rc = 0;
100 	int datalen;
101 	int ahslen;
102 
103 	/* verify PDU length */
104 	datalen = ntoh24(hdr->dlength);
105 	if (datalen > rx_data_len || (datalen + 4) < rx_data_len) {
106 		iser_err("wrong datalen %d (hdr), %d (IB)\n",
107 			datalen, rx_data_len);
108 		rc = ISCSI_ERR_DATALEN;
109 		goto error;
110 	}
111 
112 	if (datalen != rx_data_len)
113 		iser_dbg("aligned datalen (%d) hdr, %d (IB)\n",
114 			datalen, rx_data_len);
115 
116 	/* read AHS */
117 	ahslen = hdr->hlength * 4;
118 
119 	rc = iscsi_complete_pdu(conn, hdr, rx_data, rx_data_len);
120 	if (rc && rc != ISCSI_ERR_NO_SCSI_CMD)
121 		goto error;
122 
123 	return;
124 error:
125 	iscsi_conn_failure(conn, rc);
126 }
127 
128 static int iscsi_iser_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
129 {
130 	struct iscsi_iser_task *iser_task = task->dd_data;
131 
132 	task->hdr = (struct iscsi_hdr *)&iser_task->desc.iscsi_header;
133 	task->hdr_max = sizeof(iser_task->desc.iscsi_header);
134 	return 0;
135 }
136 
137 int iser_initialize_task_headers(struct iscsi_task *task,
138 						struct iser_tx_desc *tx_desc)
139 {
140 	struct iscsi_iser_conn *iser_conn = task->conn->dd_data;
141 	struct iser_device     *device    = iser_conn->ib_conn->device;
142 	struct iscsi_iser_task *iser_task = task->dd_data;
143 	u64 dma_addr;
144 
145 	dma_addr = ib_dma_map_single(device->ib_device, (void *)tx_desc,
146 				ISER_HEADERS_LEN, DMA_TO_DEVICE);
147 	if (ib_dma_mapping_error(device->ib_device, dma_addr))
148 		return -ENOMEM;
149 
150 	tx_desc->dma_addr = dma_addr;
151 	tx_desc->tx_sg[0].addr   = tx_desc->dma_addr;
152 	tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
153 	tx_desc->tx_sg[0].lkey   = device->mr->lkey;
154 
155 	iser_task->iser_conn		= iser_conn;
156 	return 0;
157 }
158 /**
159  * iscsi_iser_task_init - Initialize task
160  * @task: iscsi task
161  *
162  * Initialize the task for the scsi command or mgmt command.
163  */
164 static int
165 iscsi_iser_task_init(struct iscsi_task *task)
166 {
167 	struct iscsi_iser_task *iser_task = task->dd_data;
168 
169 	if (iser_initialize_task_headers(task, &iser_task->desc))
170 			return -ENOMEM;
171 
172 	/* mgmt task */
173 	if (!task->sc)
174 		return 0;
175 
176 	iser_task->command_sent = 0;
177 	iser_task_rdma_init(iser_task);
178 	return 0;
179 }
180 
181 /**
182  * iscsi_iser_mtask_xmit - xmit management(immediate) task
183  * @conn: iscsi connection
184  * @task: task management task
185  *
186  * Notes:
187  *	The function can return -EAGAIN in which case caller must
188  *	call it again later, or recover. '0' return code means successful
189  *	xmit.
190  *
191  **/
192 static int
193 iscsi_iser_mtask_xmit(struct iscsi_conn *conn, struct iscsi_task *task)
194 {
195 	int error = 0;
196 
197 	iser_dbg("mtask xmit [cid %d itt 0x%x]\n", conn->id, task->itt);
198 
199 	error = iser_send_control(conn, task);
200 
201 	/* since iser xmits control with zero copy, tasks can not be recycled
202 	 * right after sending them.
203 	 * The recycling scheme is based on whether a response is expected
204 	 * - if yes, the task is recycled at iscsi_complete_pdu
205 	 * - if no,  the task is recycled at iser_snd_completion
206 	 */
207 	return error;
208 }
209 
210 static int
211 iscsi_iser_task_xmit_unsol_data(struct iscsi_conn *conn,
212 				 struct iscsi_task *task)
213 {
214 	struct iscsi_r2t_info *r2t = &task->unsol_r2t;
215 	struct iscsi_data hdr;
216 	int error = 0;
217 
218 	/* Send data-out PDUs while there's still unsolicited data to send */
219 	while (iscsi_task_has_unsol_data(task)) {
220 		iscsi_prep_data_out_pdu(task, r2t, &hdr);
221 		iser_dbg("Sending data-out: itt 0x%x, data count %d\n",
222 			   hdr.itt, r2t->data_count);
223 
224 		/* the buffer description has been passed with the command */
225 		/* Send the command */
226 		error = iser_send_data_out(conn, task, &hdr);
227 		if (error) {
228 			r2t->datasn--;
229 			goto iscsi_iser_task_xmit_unsol_data_exit;
230 		}
231 		r2t->sent += r2t->data_count;
232 		iser_dbg("Need to send %d more as data-out PDUs\n",
233 			   r2t->data_length - r2t->sent);
234 	}
235 
236 iscsi_iser_task_xmit_unsol_data_exit:
237 	return error;
238 }
239 
240 static int
241 iscsi_iser_task_xmit(struct iscsi_task *task)
242 {
243 	struct iscsi_conn *conn = task->conn;
244 	struct iscsi_iser_task *iser_task = task->dd_data;
245 	int error = 0;
246 
247 	if (!task->sc)
248 		return iscsi_iser_mtask_xmit(conn, task);
249 
250 	if (task->sc->sc_data_direction == DMA_TO_DEVICE) {
251 		BUG_ON(scsi_bufflen(task->sc) == 0);
252 
253 		iser_dbg("cmd [itt %x total %d imm %d unsol_data %d\n",
254 			   task->itt, scsi_bufflen(task->sc),
255 			   task->imm_count, task->unsol_r2t.data_length);
256 	}
257 
258 	iser_dbg("ctask xmit [cid %d itt 0x%x]\n",
259 		   conn->id, task->itt);
260 
261 	/* Send the cmd PDU */
262 	if (!iser_task->command_sent) {
263 		error = iser_send_command(conn, task);
264 		if (error)
265 			goto iscsi_iser_task_xmit_exit;
266 		iser_task->command_sent = 1;
267 	}
268 
269 	/* Send unsolicited data-out PDU(s) if necessary */
270 	if (iscsi_task_has_unsol_data(task))
271 		error = iscsi_iser_task_xmit_unsol_data(conn, task);
272 
273  iscsi_iser_task_xmit_exit:
274 	return error;
275 }
276 
277 static void iscsi_iser_cleanup_task(struct iscsi_task *task)
278 {
279 	struct iscsi_iser_task *iser_task = task->dd_data;
280 	struct iser_tx_desc	*tx_desc = &iser_task->desc;
281 
282 	struct iscsi_iser_conn *iser_conn = task->conn->dd_data;
283 	struct iser_device     *device    = iser_conn->ib_conn->device;
284 
285 	ib_dma_unmap_single(device->ib_device,
286 		tx_desc->dma_addr, ISER_HEADERS_LEN, DMA_TO_DEVICE);
287 
288 	/* mgmt tasks do not need special cleanup */
289 	if (!task->sc)
290 		return;
291 
292 	if (iser_task->status == ISER_TASK_STATUS_STARTED) {
293 		iser_task->status = ISER_TASK_STATUS_COMPLETED;
294 		iser_task_rdma_finalize(iser_task);
295 	}
296 }
297 
298 static struct iscsi_cls_conn *
299 iscsi_iser_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
300 {
301 	struct iscsi_conn *conn;
302 	struct iscsi_cls_conn *cls_conn;
303 	struct iscsi_iser_conn *iser_conn;
304 
305 	cls_conn = iscsi_conn_setup(cls_session, sizeof(*iser_conn), conn_idx);
306 	if (!cls_conn)
307 		return NULL;
308 	conn = cls_conn->dd_data;
309 
310 	/*
311 	 * due to issues with the login code re iser sematics
312 	 * this not set in iscsi_conn_setup - FIXME
313 	 */
314 	conn->max_recv_dlength = ISER_RECV_DATA_SEG_LEN;
315 
316 	iser_conn = conn->dd_data;
317 	conn->dd_data = iser_conn;
318 	iser_conn->iscsi_conn = conn;
319 
320 	return cls_conn;
321 }
322 
323 static void
324 iscsi_iser_conn_destroy(struct iscsi_cls_conn *cls_conn)
325 {
326 	struct iscsi_conn *conn = cls_conn->dd_data;
327 	struct iscsi_iser_conn *iser_conn = conn->dd_data;
328 	struct iser_conn *ib_conn = iser_conn->ib_conn;
329 
330 	iscsi_conn_teardown(cls_conn);
331 	/*
332 	 * Userspace will normally call the stop callback and
333 	 * already have freed the ib_conn, but if it goofed up then
334 	 * we free it here.
335 	 */
336 	if (ib_conn) {
337 		ib_conn->iser_conn = NULL;
338 		iser_conn_put(ib_conn, 1); /* deref iscsi/ib conn unbinding */
339 	}
340 }
341 
342 static int
343 iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session,
344 		     struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
345 		     int is_leading)
346 {
347 	struct iscsi_conn *conn = cls_conn->dd_data;
348 	struct iscsi_iser_conn *iser_conn;
349 	struct iser_conn *ib_conn;
350 	struct iscsi_endpoint *ep;
351 	int error;
352 
353 	error = iscsi_conn_bind(cls_session, cls_conn, is_leading);
354 	if (error)
355 		return error;
356 
357 	/* the transport ep handle comes from user space so it must be
358 	 * verified against the global ib connections list */
359 	ep = iscsi_lookup_endpoint(transport_eph);
360 	if (!ep) {
361 		iser_err("can't bind eph %llx\n",
362 			 (unsigned long long)transport_eph);
363 		return -EINVAL;
364 	}
365 	ib_conn = ep->dd_data;
366 
367 	if (iser_alloc_rx_descriptors(ib_conn))
368 		return -ENOMEM;
369 
370 	/* binds the iSER connection retrieved from the previously
371 	 * connected ep_handle to the iSCSI layer connection. exchanges
372 	 * connection pointers */
373 	iser_err("binding iscsi/iser conn %p %p to ib_conn %p\n",
374 					conn, conn->dd_data, ib_conn);
375 	iser_conn = conn->dd_data;
376 	ib_conn->iser_conn = iser_conn;
377 	iser_conn->ib_conn  = ib_conn;
378 	iser_conn_get(ib_conn); /* ref iscsi/ib conn binding */
379 	return 0;
380 }
381 
382 static void
383 iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
384 {
385 	struct iscsi_conn *conn = cls_conn->dd_data;
386 	struct iscsi_iser_conn *iser_conn = conn->dd_data;
387 	struct iser_conn *ib_conn = iser_conn->ib_conn;
388 
389 	/*
390 	 * Userspace may have goofed up and not bound the connection or
391 	 * might have only partially setup the connection.
392 	 */
393 	if (ib_conn) {
394 		iscsi_conn_stop(cls_conn, flag);
395 		/*
396 		 * There is no unbind event so the stop callback
397 		 * must release the ref from the bind.
398 		 */
399 		iser_conn_put(ib_conn, 1); /* deref iscsi/ib conn unbinding */
400 	}
401 	iser_conn->ib_conn = NULL;
402 }
403 
404 static void iscsi_iser_session_destroy(struct iscsi_cls_session *cls_session)
405 {
406 	struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
407 
408 	iscsi_session_teardown(cls_session);
409 	iscsi_host_remove(shost);
410 	iscsi_host_free(shost);
411 }
412 
413 static struct iscsi_cls_session *
414 iscsi_iser_session_create(struct iscsi_endpoint *ep,
415 			  uint16_t cmds_max, uint16_t qdepth,
416 			  uint32_t initial_cmdsn)
417 {
418 	struct iscsi_cls_session *cls_session;
419 	struct iscsi_session *session;
420 	struct Scsi_Host *shost;
421 	struct iser_conn *ib_conn;
422 
423 	shost = iscsi_host_alloc(&iscsi_iser_sht, 0, 0);
424 	if (!shost)
425 		return NULL;
426 	shost->transportt = iscsi_iser_scsi_transport;
427 	shost->max_lun = iscsi_max_lun;
428 	shost->max_id = 0;
429 	shost->max_channel = 0;
430 	shost->max_cmd_len = 16;
431 
432 	/*
433 	 * older userspace tools (before 2.0-870) did not pass us
434 	 * the leading conn's ep so this will be NULL;
435 	 */
436 	if (ep)
437 		ib_conn = ep->dd_data;
438 
439 	if (iscsi_host_add(shost,
440 			   ep ? ib_conn->device->ib_device->dma_device : NULL))
441 		goto free_host;
442 
443 	/*
444 	 * we do not support setting can_queue cmd_per_lun from userspace yet
445 	 * because we preallocate so many resources
446 	 */
447 	cls_session = iscsi_session_setup(&iscsi_iser_transport, shost,
448 					  ISCSI_DEF_XMIT_CMDS_MAX, 0,
449 					  sizeof(struct iscsi_iser_task),
450 					  initial_cmdsn, 0);
451 	if (!cls_session)
452 		goto remove_host;
453 	session = cls_session->dd_data;
454 
455 	shost->can_queue = session->scsi_cmds_max;
456 	return cls_session;
457 
458 remove_host:
459 	iscsi_host_remove(shost);
460 free_host:
461 	iscsi_host_free(shost);
462 	return NULL;
463 }
464 
465 static int
466 iscsi_iser_set_param(struct iscsi_cls_conn *cls_conn,
467 		     enum iscsi_param param, char *buf, int buflen)
468 {
469 	int value;
470 
471 	switch (param) {
472 	case ISCSI_PARAM_MAX_RECV_DLENGTH:
473 		/* TBD */
474 		break;
475 	case ISCSI_PARAM_HDRDGST_EN:
476 		sscanf(buf, "%d", &value);
477 		if (value) {
478 			printk(KERN_ERR "DataDigest wasn't negotiated to None");
479 			return -EPROTO;
480 		}
481 		break;
482 	case ISCSI_PARAM_DATADGST_EN:
483 		sscanf(buf, "%d", &value);
484 		if (value) {
485 			printk(KERN_ERR "DataDigest wasn't negotiated to None");
486 			return -EPROTO;
487 		}
488 		break;
489 	case ISCSI_PARAM_IFMARKER_EN:
490 		sscanf(buf, "%d", &value);
491 		if (value) {
492 			printk(KERN_ERR "IFMarker wasn't negotiated to No");
493 			return -EPROTO;
494 		}
495 		break;
496 	case ISCSI_PARAM_OFMARKER_EN:
497 		sscanf(buf, "%d", &value);
498 		if (value) {
499 			printk(KERN_ERR "OFMarker wasn't negotiated to No");
500 			return -EPROTO;
501 		}
502 		break;
503 	default:
504 		return iscsi_set_param(cls_conn, param, buf, buflen);
505 	}
506 
507 	return 0;
508 }
509 
510 static void
511 iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
512 {
513 	struct iscsi_conn *conn = cls_conn->dd_data;
514 
515 	stats->txdata_octets = conn->txdata_octets;
516 	stats->rxdata_octets = conn->rxdata_octets;
517 	stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
518 	stats->dataout_pdus = conn->dataout_pdus_cnt;
519 	stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
520 	stats->datain_pdus = conn->datain_pdus_cnt; /* always 0 */
521 	stats->r2t_pdus = conn->r2t_pdus_cnt; /* always 0 */
522 	stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
523 	stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
524 	stats->custom_length = 4;
525 	strcpy(stats->custom[0].desc, "qp_tx_queue_full");
526 	stats->custom[0].value = 0; /* TB iser_conn->qp_tx_queue_full; */
527 	strcpy(stats->custom[1].desc, "fmr_map_not_avail");
528 	stats->custom[1].value = 0; /* TB iser_conn->fmr_map_not_avail */;
529 	strcpy(stats->custom[2].desc, "eh_abort_cnt");
530 	stats->custom[2].value = conn->eh_abort_cnt;
531 	strcpy(stats->custom[3].desc, "fmr_unalign_cnt");
532 	stats->custom[3].value = conn->fmr_unalign_cnt;
533 }
534 
535 static int iscsi_iser_get_ep_param(struct iscsi_endpoint *ep,
536 				   enum iscsi_param param, char *buf)
537 {
538 	struct iser_conn *ib_conn = ep->dd_data;
539 	int len;
540 
541 	switch (param) {
542 	case ISCSI_PARAM_CONN_PORT:
543 	case ISCSI_PARAM_CONN_ADDRESS:
544 		if (!ib_conn || !ib_conn->cma_id)
545 			return -ENOTCONN;
546 
547 		return iscsi_conn_get_addr_param((struct sockaddr_storage *)
548 					&ib_conn->cma_id->route.addr.dst_addr,
549 					param, buf);
550 		break;
551 	default:
552 		return -ENOSYS;
553 	}
554 
555 	return len;
556 }
557 
558 static struct iscsi_endpoint *
559 iscsi_iser_ep_connect(struct Scsi_Host *shost, struct sockaddr *dst_addr,
560 		      int non_blocking)
561 {
562 	int err;
563 	struct iser_conn *ib_conn;
564 	struct iscsi_endpoint *ep;
565 
566 	ep = iscsi_create_endpoint(sizeof(*ib_conn));
567 	if (!ep)
568 		return ERR_PTR(-ENOMEM);
569 
570 	ib_conn = ep->dd_data;
571 	ib_conn->ep = ep;
572 	iser_conn_init(ib_conn);
573 
574 	err = iser_connect(ib_conn, NULL, (struct sockaddr_in *)dst_addr,
575 			   non_blocking);
576 	if (err)
577 		return ERR_PTR(err);
578 
579 	return ep;
580 }
581 
582 static int
583 iscsi_iser_ep_poll(struct iscsi_endpoint *ep, int timeout_ms)
584 {
585 	struct iser_conn *ib_conn;
586 	int rc;
587 
588 	ib_conn = ep->dd_data;
589 	rc = wait_event_interruptible_timeout(ib_conn->wait,
590 			     ib_conn->state == ISER_CONN_UP,
591 			     msecs_to_jiffies(timeout_ms));
592 
593 	/* if conn establishment failed, return error code to iscsi */
594 	if (!rc &&
595 	    (ib_conn->state == ISER_CONN_TERMINATING ||
596 	     ib_conn->state == ISER_CONN_DOWN))
597 		rc = -1;
598 
599 	iser_err("ib conn %p rc = %d\n", ib_conn, rc);
600 
601 	if (rc > 0)
602 		return 1; /* success, this is the equivalent of POLLOUT */
603 	else if (!rc)
604 		return 0; /* timeout */
605 	else
606 		return rc; /* signal */
607 }
608 
609 static void
610 iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep)
611 {
612 	struct iser_conn *ib_conn;
613 
614 	ib_conn = ep->dd_data;
615 	if (ib_conn->iser_conn)
616 		/*
617 		 * Must suspend xmit path if the ep is bound to the
618 		 * iscsi_conn, so we know we are not accessing the ib_conn
619 		 * when we free it.
620 		 *
621 		 * This may not be bound if the ep poll failed.
622 		 */
623 		iscsi_suspend_tx(ib_conn->iser_conn->iscsi_conn);
624 
625 
626 	iser_err("ib conn %p state %d\n",ib_conn, ib_conn->state);
627 	iser_conn_terminate(ib_conn);
628 }
629 
630 static umode_t iser_attr_is_visible(int param_type, int param)
631 {
632 	switch (param_type) {
633 	case ISCSI_HOST_PARAM:
634 		switch (param) {
635 		case ISCSI_HOST_PARAM_NETDEV_NAME:
636 		case ISCSI_HOST_PARAM_HWADDRESS:
637 		case ISCSI_HOST_PARAM_INITIATOR_NAME:
638 			return S_IRUGO;
639 		default:
640 			return 0;
641 		}
642 	case ISCSI_PARAM:
643 		switch (param) {
644 		case ISCSI_PARAM_MAX_RECV_DLENGTH:
645 		case ISCSI_PARAM_MAX_XMIT_DLENGTH:
646 		case ISCSI_PARAM_HDRDGST_EN:
647 		case ISCSI_PARAM_DATADGST_EN:
648 		case ISCSI_PARAM_CONN_ADDRESS:
649 		case ISCSI_PARAM_CONN_PORT:
650 		case ISCSI_PARAM_EXP_STATSN:
651 		case ISCSI_PARAM_PERSISTENT_ADDRESS:
652 		case ISCSI_PARAM_PERSISTENT_PORT:
653 		case ISCSI_PARAM_PING_TMO:
654 		case ISCSI_PARAM_RECV_TMO:
655 		case ISCSI_PARAM_INITIAL_R2T_EN:
656 		case ISCSI_PARAM_MAX_R2T:
657 		case ISCSI_PARAM_IMM_DATA_EN:
658 		case ISCSI_PARAM_FIRST_BURST:
659 		case ISCSI_PARAM_MAX_BURST:
660 		case ISCSI_PARAM_PDU_INORDER_EN:
661 		case ISCSI_PARAM_DATASEQ_INORDER_EN:
662 		case ISCSI_PARAM_TARGET_NAME:
663 		case ISCSI_PARAM_TPGT:
664 		case ISCSI_PARAM_USERNAME:
665 		case ISCSI_PARAM_PASSWORD:
666 		case ISCSI_PARAM_USERNAME_IN:
667 		case ISCSI_PARAM_PASSWORD_IN:
668 		case ISCSI_PARAM_FAST_ABORT:
669 		case ISCSI_PARAM_ABORT_TMO:
670 		case ISCSI_PARAM_LU_RESET_TMO:
671 		case ISCSI_PARAM_TGT_RESET_TMO:
672 		case ISCSI_PARAM_IFACE_NAME:
673 		case ISCSI_PARAM_INITIATOR_NAME:
674 			return S_IRUGO;
675 		default:
676 			return 0;
677 		}
678 	}
679 
680 	return 0;
681 }
682 
683 static struct scsi_host_template iscsi_iser_sht = {
684 	.module                 = THIS_MODULE,
685 	.name                   = "iSCSI Initiator over iSER, v." DRV_VER,
686 	.queuecommand           = iscsi_queuecommand,
687 	.change_queue_depth	= iscsi_change_queue_depth,
688 	.sg_tablesize           = ISCSI_ISER_SG_TABLESIZE,
689 	.max_sectors		= 1024,
690 	.cmd_per_lun            = ISER_DEF_CMD_PER_LUN,
691 	.eh_abort_handler       = iscsi_eh_abort,
692 	.eh_device_reset_handler= iscsi_eh_device_reset,
693 	.eh_target_reset_handler = iscsi_eh_recover_target,
694 	.target_alloc		= iscsi_target_alloc,
695 	.use_clustering         = DISABLE_CLUSTERING,
696 	.proc_name              = "iscsi_iser",
697 	.this_id                = -1,
698 };
699 
700 static struct iscsi_transport iscsi_iser_transport = {
701 	.owner                  = THIS_MODULE,
702 	.name                   = "iser",
703 	.caps                   = CAP_RECOVERY_L0 | CAP_MULTI_R2T,
704 	/* session management */
705 	.create_session         = iscsi_iser_session_create,
706 	.destroy_session        = iscsi_iser_session_destroy,
707 	/* connection management */
708 	.create_conn            = iscsi_iser_conn_create,
709 	.bind_conn              = iscsi_iser_conn_bind,
710 	.destroy_conn           = iscsi_iser_conn_destroy,
711 	.attr_is_visible	= iser_attr_is_visible,
712 	.set_param              = iscsi_iser_set_param,
713 	.get_conn_param		= iscsi_conn_get_param,
714 	.get_ep_param		= iscsi_iser_get_ep_param,
715 	.get_session_param	= iscsi_session_get_param,
716 	.start_conn             = iscsi_conn_start,
717 	.stop_conn              = iscsi_iser_conn_stop,
718 	/* iscsi host params */
719 	.get_host_param		= iscsi_host_get_param,
720 	.set_host_param		= iscsi_host_set_param,
721 	/* IO */
722 	.send_pdu		= iscsi_conn_send_pdu,
723 	.get_stats		= iscsi_iser_conn_get_stats,
724 	.init_task		= iscsi_iser_task_init,
725 	.xmit_task		= iscsi_iser_task_xmit,
726 	.cleanup_task		= iscsi_iser_cleanup_task,
727 	.alloc_pdu		= iscsi_iser_pdu_alloc,
728 	/* recovery */
729 	.session_recovery_timedout = iscsi_session_recovery_timedout,
730 
731 	.ep_connect             = iscsi_iser_ep_connect,
732 	.ep_poll                = iscsi_iser_ep_poll,
733 	.ep_disconnect          = iscsi_iser_ep_disconnect
734 };
735 
736 static int __init iser_init(void)
737 {
738 	int err;
739 
740 	iser_dbg("Starting iSER datamover...\n");
741 
742 	if (iscsi_max_lun < 1) {
743 		printk(KERN_ERR "Invalid max_lun value of %u\n", iscsi_max_lun);
744 		return -EINVAL;
745 	}
746 
747 	memset(&ig, 0, sizeof(struct iser_global));
748 
749 	ig.desc_cache = kmem_cache_create("iser_descriptors",
750 					  sizeof(struct iser_tx_desc),
751 					  0, SLAB_HWCACHE_ALIGN,
752 					  NULL);
753 	if (ig.desc_cache == NULL)
754 		return -ENOMEM;
755 
756 	/* device init is called only after the first addr resolution */
757 	mutex_init(&ig.device_list_mutex);
758 	INIT_LIST_HEAD(&ig.device_list);
759 	mutex_init(&ig.connlist_mutex);
760 	INIT_LIST_HEAD(&ig.connlist);
761 
762 	iscsi_iser_scsi_transport = iscsi_register_transport(
763 							&iscsi_iser_transport);
764 	if (!iscsi_iser_scsi_transport) {
765 		iser_err("iscsi_register_transport failed\n");
766 		err = -EINVAL;
767 		goto register_transport_failure;
768 	}
769 
770 	return 0;
771 
772 register_transport_failure:
773 	kmem_cache_destroy(ig.desc_cache);
774 
775 	return err;
776 }
777 
778 static void __exit iser_exit(void)
779 {
780 	iser_dbg("Removing iSER datamover...\n");
781 	iscsi_unregister_transport(&iscsi_iser_transport);
782 	kmem_cache_destroy(ig.desc_cache);
783 }
784 
785 module_init(iser_init);
786 module_exit(iser_exit);
787