xref: /linux/drivers/target/target_core_pscsi.c (revision 4949009eb8d40a441dcddcd96e101e77d31cf1b2)
1 /*******************************************************************************
2  * Filename:  target_core_pscsi.c
3  *
4  * This file contains the generic target mode <-> Linux SCSI subsystem plugin.
5  *
6  * (c) Copyright 2003-2013 Datera, Inc.
7  *
8  * Nicholas A. Bellinger <nab@kernel.org>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23  *
24  ******************************************************************************/
25 
26 #include <linux/string.h>
27 #include <linux/parser.h>
28 #include <linux/timer.h>
29 #include <linux/blkdev.h>
30 #include <linux/blk_types.h>
31 #include <linux/slab.h>
32 #include <linux/spinlock.h>
33 #include <linux/genhd.h>
34 #include <linux/cdrom.h>
35 #include <linux/ratelimit.h>
36 #include <linux/module.h>
37 #include <asm/unaligned.h>
38 
39 #include <scsi/scsi.h>
40 #include <scsi/scsi_device.h>
41 #include <scsi/scsi_cmnd.h>
42 #include <scsi/scsi_host.h>
43 #include <scsi/scsi_tcq.h>
44 
45 #include <target/target_core_base.h>
46 #include <target/target_core_backend.h>
47 #include <target/target_core_backend_configfs.h>
48 
49 #include "target_core_alua.h"
50 #include "target_core_pscsi.h"
51 
52 #define ISPRINT(a)  ((a >= ' ') && (a <= '~'))
53 
54 static inline struct pscsi_dev_virt *PSCSI_DEV(struct se_device *dev)
55 {
56 	return container_of(dev, struct pscsi_dev_virt, dev);
57 }
58 
59 static struct se_subsystem_api pscsi_template;
60 
61 static sense_reason_t pscsi_execute_cmd(struct se_cmd *cmd);
62 static void pscsi_req_done(struct request *, int);
63 
64 /*	pscsi_attach_hba():
65  *
66  * 	pscsi_get_sh() used scsi_host_lookup() to locate struct Scsi_Host.
67  *	from the passed SCSI Host ID.
68  */
69 static int pscsi_attach_hba(struct se_hba *hba, u32 host_id)
70 {
71 	struct pscsi_hba_virt *phv;
72 
73 	phv = kzalloc(sizeof(struct pscsi_hba_virt), GFP_KERNEL);
74 	if (!phv) {
75 		pr_err("Unable to allocate struct pscsi_hba_virt\n");
76 		return -ENOMEM;
77 	}
78 	phv->phv_host_id = host_id;
79 	phv->phv_mode = PHV_VIRTUAL_HOST_ID;
80 
81 	hba->hba_ptr = phv;
82 
83 	pr_debug("CORE_HBA[%d] - TCM SCSI HBA Driver %s on"
84 		" Generic Target Core Stack %s\n", hba->hba_id,
85 		PSCSI_VERSION, TARGET_CORE_MOD_VERSION);
86 	pr_debug("CORE_HBA[%d] - Attached SCSI HBA to Generic\n",
87 	       hba->hba_id);
88 
89 	return 0;
90 }
91 
92 static void pscsi_detach_hba(struct se_hba *hba)
93 {
94 	struct pscsi_hba_virt *phv = hba->hba_ptr;
95 	struct Scsi_Host *scsi_host = phv->phv_lld_host;
96 
97 	if (scsi_host) {
98 		scsi_host_put(scsi_host);
99 
100 		pr_debug("CORE_HBA[%d] - Detached SCSI HBA: %s from"
101 			" Generic Target Core\n", hba->hba_id,
102 			(scsi_host->hostt->name) ? (scsi_host->hostt->name) :
103 			"Unknown");
104 	} else
105 		pr_debug("CORE_HBA[%d] - Detached Virtual SCSI HBA"
106 			" from Generic Target Core\n", hba->hba_id);
107 
108 	kfree(phv);
109 	hba->hba_ptr = NULL;
110 }
111 
112 static int pscsi_pmode_enable_hba(struct se_hba *hba, unsigned long mode_flag)
113 {
114 	struct pscsi_hba_virt *phv = hba->hba_ptr;
115 	struct Scsi_Host *sh = phv->phv_lld_host;
116 	/*
117 	 * Release the struct Scsi_Host
118 	 */
119 	if (!mode_flag) {
120 		if (!sh)
121 			return 0;
122 
123 		phv->phv_lld_host = NULL;
124 		phv->phv_mode = PHV_VIRTUAL_HOST_ID;
125 
126 		pr_debug("CORE_HBA[%d] - Disabled pSCSI HBA Passthrough"
127 			" %s\n", hba->hba_id, (sh->hostt->name) ?
128 			(sh->hostt->name) : "Unknown");
129 
130 		scsi_host_put(sh);
131 		return 0;
132 	}
133 	/*
134 	 * Otherwise, locate struct Scsi_Host from the original passed
135 	 * pSCSI Host ID and enable for phba mode
136 	 */
137 	sh = scsi_host_lookup(phv->phv_host_id);
138 	if (!sh) {
139 		pr_err("pSCSI: Unable to locate SCSI Host for"
140 			" phv_host_id: %d\n", phv->phv_host_id);
141 		return -EINVAL;
142 	}
143 
144 	phv->phv_lld_host = sh;
145 	phv->phv_mode = PHV_LLD_SCSI_HOST_NO;
146 
147 	pr_debug("CORE_HBA[%d] - Enabled pSCSI HBA Passthrough %s\n",
148 		hba->hba_id, (sh->hostt->name) ? (sh->hostt->name) : "Unknown");
149 
150 	return 1;
151 }
152 
153 static void pscsi_tape_read_blocksize(struct se_device *dev,
154 		struct scsi_device *sdev)
155 {
156 	unsigned char cdb[MAX_COMMAND_SIZE], *buf;
157 	int ret;
158 
159 	buf = kzalloc(12, GFP_KERNEL);
160 	if (!buf)
161 		return;
162 
163 	memset(cdb, 0, MAX_COMMAND_SIZE);
164 	cdb[0] = MODE_SENSE;
165 	cdb[4] = 0x0c; /* 12 bytes */
166 
167 	ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf, 12, NULL,
168 			HZ, 1, NULL);
169 	if (ret)
170 		goto out_free;
171 
172 	/*
173 	 * If MODE_SENSE still returns zero, set the default value to 1024.
174 	 */
175 	sdev->sector_size = (buf[9] << 16) | (buf[10] << 8) | (buf[11]);
176 	if (!sdev->sector_size)
177 		sdev->sector_size = 1024;
178 out_free:
179 	kfree(buf);
180 }
181 
182 static void
183 pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
184 {
185 	unsigned char *buf;
186 
187 	if (sdev->inquiry_len < INQUIRY_LEN)
188 		return;
189 
190 	buf = sdev->inquiry;
191 	if (!buf)
192 		return;
193 	/*
194 	 * Use sdev->inquiry from drivers/scsi/scsi_scan.c:scsi_alloc_sdev()
195 	 */
196 	memcpy(&wwn->vendor[0], &buf[8], sizeof(wwn->vendor));
197 	memcpy(&wwn->model[0], &buf[16], sizeof(wwn->model));
198 	memcpy(&wwn->revision[0], &buf[32], sizeof(wwn->revision));
199 }
200 
201 static int
202 pscsi_get_inquiry_vpd_serial(struct scsi_device *sdev, struct t10_wwn *wwn)
203 {
204 	unsigned char cdb[MAX_COMMAND_SIZE], *buf;
205 	int ret;
206 
207 	buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
208 	if (!buf)
209 		return -ENOMEM;
210 
211 	memset(cdb, 0, MAX_COMMAND_SIZE);
212 	cdb[0] = INQUIRY;
213 	cdb[1] = 0x01; /* Query VPD */
214 	cdb[2] = 0x80; /* Unit Serial Number */
215 	cdb[3] = (INQUIRY_VPD_SERIAL_LEN >> 8) & 0xff;
216 	cdb[4] = (INQUIRY_VPD_SERIAL_LEN & 0xff);
217 
218 	ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
219 			      INQUIRY_VPD_SERIAL_LEN, NULL, HZ, 1, NULL);
220 	if (ret)
221 		goto out_free;
222 
223 	snprintf(&wwn->unit_serial[0], INQUIRY_VPD_SERIAL_LEN, "%s", &buf[4]);
224 
225 	wwn->t10_dev->dev_flags |= DF_FIRMWARE_VPD_UNIT_SERIAL;
226 
227 	kfree(buf);
228 	return 0;
229 
230 out_free:
231 	kfree(buf);
232 	return -EPERM;
233 }
234 
235 static void
236 pscsi_get_inquiry_vpd_device_ident(struct scsi_device *sdev,
237 		struct t10_wwn *wwn)
238 {
239 	unsigned char cdb[MAX_COMMAND_SIZE], *buf, *page_83;
240 	int ident_len, page_len, off = 4, ret;
241 	struct t10_vpd *vpd;
242 
243 	buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
244 	if (!buf)
245 		return;
246 
247 	memset(cdb, 0, MAX_COMMAND_SIZE);
248 	cdb[0] = INQUIRY;
249 	cdb[1] = 0x01; /* Query VPD */
250 	cdb[2] = 0x83; /* Device Identifier */
251 	cdb[3] = (INQUIRY_VPD_DEVICE_IDENTIFIER_LEN >> 8) & 0xff;
252 	cdb[4] = (INQUIRY_VPD_DEVICE_IDENTIFIER_LEN & 0xff);
253 
254 	ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
255 			      INQUIRY_VPD_DEVICE_IDENTIFIER_LEN,
256 			      NULL, HZ, 1, NULL);
257 	if (ret)
258 		goto out;
259 
260 	page_len = (buf[2] << 8) | buf[3];
261 	while (page_len > 0) {
262 		/* Grab a pointer to the Identification descriptor */
263 		page_83 = &buf[off];
264 		ident_len = page_83[3];
265 		if (!ident_len) {
266 			pr_err("page_83[3]: identifier"
267 					" length zero!\n");
268 			break;
269 		}
270 		pr_debug("T10 VPD Identifier Length: %d\n", ident_len);
271 
272 		vpd = kzalloc(sizeof(struct t10_vpd), GFP_KERNEL);
273 		if (!vpd) {
274 			pr_err("Unable to allocate memory for"
275 					" struct t10_vpd\n");
276 			goto out;
277 		}
278 		INIT_LIST_HEAD(&vpd->vpd_list);
279 
280 		transport_set_vpd_proto_id(vpd, page_83);
281 		transport_set_vpd_assoc(vpd, page_83);
282 
283 		if (transport_set_vpd_ident_type(vpd, page_83) < 0) {
284 			off += (ident_len + 4);
285 			page_len -= (ident_len + 4);
286 			kfree(vpd);
287 			continue;
288 		}
289 		if (transport_set_vpd_ident(vpd, page_83) < 0) {
290 			off += (ident_len + 4);
291 			page_len -= (ident_len + 4);
292 			kfree(vpd);
293 			continue;
294 		}
295 
296 		list_add_tail(&vpd->vpd_list, &wwn->t10_vpd_list);
297 		off += (ident_len + 4);
298 		page_len -= (ident_len + 4);
299 	}
300 
301 out:
302 	kfree(buf);
303 }
304 
305 static int pscsi_add_device_to_list(struct se_device *dev,
306 		struct scsi_device *sd)
307 {
308 	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
309 	struct request_queue *q = sd->request_queue;
310 
311 	pdv->pdv_sd = sd;
312 
313 	if (!sd->queue_depth) {
314 		sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
315 
316 		pr_err("Set broken SCSI Device %d:%d:%llu"
317 			" queue_depth to %d\n", sd->channel, sd->id,
318 				sd->lun, sd->queue_depth);
319 	}
320 
321 	dev->dev_attrib.hw_block_size = sd->sector_size;
322 	dev->dev_attrib.hw_max_sectors =
323 		min_t(int, sd->host->max_sectors, queue_max_hw_sectors(q));
324 	dev->dev_attrib.hw_queue_depth = sd->queue_depth;
325 
326 	/*
327 	 * Setup our standard INQUIRY info into se_dev->t10_wwn
328 	 */
329 	pscsi_set_inquiry_info(sd, &dev->t10_wwn);
330 
331 	/*
332 	 * Locate VPD WWN Information used for various purposes within
333 	 * the Storage Engine.
334 	 */
335 	if (!pscsi_get_inquiry_vpd_serial(sd, &dev->t10_wwn)) {
336 		/*
337 		 * If VPD Unit Serial returned GOOD status, try
338 		 * VPD Device Identification page (0x83).
339 		 */
340 		pscsi_get_inquiry_vpd_device_ident(sd, &dev->t10_wwn);
341 	}
342 
343 	/*
344 	 * For TYPE_TAPE, attempt to determine blocksize with MODE_SENSE.
345 	 */
346 	if (sd->type == TYPE_TAPE)
347 		pscsi_tape_read_blocksize(dev, sd);
348 	return 0;
349 }
350 
351 static struct se_device *pscsi_alloc_device(struct se_hba *hba,
352 		const char *name)
353 {
354 	struct pscsi_dev_virt *pdv;
355 
356 	pdv = kzalloc(sizeof(struct pscsi_dev_virt), GFP_KERNEL);
357 	if (!pdv) {
358 		pr_err("Unable to allocate memory for struct pscsi_dev_virt\n");
359 		return NULL;
360 	}
361 
362 	pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
363 	return &pdv->dev;
364 }
365 
366 /*
367  * Called with struct Scsi_Host->host_lock called.
368  */
369 static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
370 	__releases(sh->host_lock)
371 {
372 	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
373 	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
374 	struct Scsi_Host *sh = sd->host;
375 	struct block_device *bd;
376 	int ret;
377 
378 	if (scsi_device_get(sd)) {
379 		pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
380 			sh->host_no, sd->channel, sd->id, sd->lun);
381 		spin_unlock_irq(sh->host_lock);
382 		return -EIO;
383 	}
384 	spin_unlock_irq(sh->host_lock);
385 	/*
386 	 * Claim exclusive struct block_device access to struct scsi_device
387 	 * for TYPE_DISK using supplied udev_path
388 	 */
389 	bd = blkdev_get_by_path(dev->udev_path,
390 				FMODE_WRITE|FMODE_READ|FMODE_EXCL, pdv);
391 	if (IS_ERR(bd)) {
392 		pr_err("pSCSI: blkdev_get_by_path() failed\n");
393 		scsi_device_put(sd);
394 		return PTR_ERR(bd);
395 	}
396 	pdv->pdv_bd = bd;
397 
398 	ret = pscsi_add_device_to_list(dev, sd);
399 	if (ret) {
400 		blkdev_put(pdv->pdv_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
401 		scsi_device_put(sd);
402 		return ret;
403 	}
404 
405 	pr_debug("CORE_PSCSI[%d] - Added TYPE_DISK for %d:%d:%d:%llu\n",
406 		phv->phv_host_id, sh->host_no, sd->channel, sd->id, sd->lun);
407 	return 0;
408 }
409 
410 /*
411  * Called with struct Scsi_Host->host_lock called.
412  */
413 static int pscsi_create_type_rom(struct se_device *dev, struct scsi_device *sd)
414 	__releases(sh->host_lock)
415 {
416 	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
417 	struct Scsi_Host *sh = sd->host;
418 	int ret;
419 
420 	if (scsi_device_get(sd)) {
421 		pr_err("scsi_device_get() failed for %d:%d:%d:%llu\n",
422 			sh->host_no, sd->channel, sd->id, sd->lun);
423 		spin_unlock_irq(sh->host_lock);
424 		return -EIO;
425 	}
426 	spin_unlock_irq(sh->host_lock);
427 
428 	ret = pscsi_add_device_to_list(dev, sd);
429 	if (ret) {
430 		scsi_device_put(sd);
431 		return ret;
432 	}
433 	pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
434 		phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
435 		sd->channel, sd->id, sd->lun);
436 
437 	return 0;
438 }
439 
440 /*
441  * Called with struct Scsi_Host->host_lock called.
442  */
443 static int pscsi_create_type_other(struct se_device *dev,
444 		struct scsi_device *sd)
445 	__releases(sh->host_lock)
446 {
447 	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
448 	struct Scsi_Host *sh = sd->host;
449 	int ret;
450 
451 	spin_unlock_irq(sh->host_lock);
452 	ret = pscsi_add_device_to_list(dev, sd);
453 	if (ret)
454 		return ret;
455 
456 	pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%llu\n",
457 		phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
458 		sd->channel, sd->id, sd->lun);
459 	return 0;
460 }
461 
462 static int pscsi_configure_device(struct se_device *dev)
463 {
464 	struct se_hba *hba = dev->se_hba;
465 	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
466 	struct scsi_device *sd;
467 	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
468 	struct Scsi_Host *sh = phv->phv_lld_host;
469 	int legacy_mode_enable = 0;
470 	int ret;
471 
472 	if (!(pdv->pdv_flags & PDF_HAS_CHANNEL_ID) ||
473 	    !(pdv->pdv_flags & PDF_HAS_TARGET_ID) ||
474 	    !(pdv->pdv_flags & PDF_HAS_LUN_ID)) {
475 		pr_err("Missing scsi_channel_id=, scsi_target_id= and"
476 			" scsi_lun_id= parameters\n");
477 		return -EINVAL;
478 	}
479 
480 	/*
481 	 * If not running in PHV_LLD_SCSI_HOST_NO mode, locate the
482 	 * struct Scsi_Host we will need to bring the TCM/pSCSI object online
483 	 */
484 	if (!sh) {
485 		if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
486 			pr_err("pSCSI: Unable to locate struct"
487 				" Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
488 			return -ENODEV;
489 		}
490 		/*
491 		 * For the newer PHV_VIRTUAL_HOST_ID struct scsi_device
492 		 * reference, we enforce that udev_path has been set
493 		 */
494 		if (!(dev->dev_flags & DF_USING_UDEV_PATH)) {
495 			pr_err("pSCSI: udev_path attribute has not"
496 				" been set before ENABLE=1\n");
497 			return -EINVAL;
498 		}
499 		/*
500 		 * If no scsi_host_id= was passed for PHV_VIRTUAL_HOST_ID,
501 		 * use the original TCM hba ID to reference Linux/SCSI Host No
502 		 * and enable for PHV_LLD_SCSI_HOST_NO mode.
503 		 */
504 		if (!(pdv->pdv_flags & PDF_HAS_VIRT_HOST_ID)) {
505 			if (hba->dev_count) {
506 				pr_err("pSCSI: Unable to set hba_mode"
507 					" with active devices\n");
508 				return -EEXIST;
509 			}
510 
511 			if (pscsi_pmode_enable_hba(hba, 1) != 1)
512 				return -ENODEV;
513 
514 			legacy_mode_enable = 1;
515 			hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
516 			sh = phv->phv_lld_host;
517 		} else {
518 			sh = scsi_host_lookup(pdv->pdv_host_id);
519 			if (!sh) {
520 				pr_err("pSCSI: Unable to locate"
521 					" pdv_host_id: %d\n", pdv->pdv_host_id);
522 				return -EINVAL;
523 			}
524 		}
525 	} else {
526 		if (phv->phv_mode == PHV_VIRTUAL_HOST_ID) {
527 			pr_err("pSCSI: PHV_VIRTUAL_HOST_ID set while"
528 				" struct Scsi_Host exists\n");
529 			return -EEXIST;
530 		}
531 	}
532 
533 	spin_lock_irq(sh->host_lock);
534 	list_for_each_entry(sd, &sh->__devices, siblings) {
535 		if ((pdv->pdv_channel_id != sd->channel) ||
536 		    (pdv->pdv_target_id != sd->id) ||
537 		    (pdv->pdv_lun_id != sd->lun))
538 			continue;
539 		/*
540 		 * Functions will release the held struct scsi_host->host_lock
541 		 * before calling calling pscsi_add_device_to_list() to register
542 		 * struct scsi_device with target_core_mod.
543 		 */
544 		switch (sd->type) {
545 		case TYPE_DISK:
546 			ret = pscsi_create_type_disk(dev, sd);
547 			break;
548 		case TYPE_ROM:
549 			ret = pscsi_create_type_rom(dev, sd);
550 			break;
551 		default:
552 			ret = pscsi_create_type_other(dev, sd);
553 			break;
554 		}
555 
556 		if (ret) {
557 			if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
558 				scsi_host_put(sh);
559 			else if (legacy_mode_enable) {
560 				pscsi_pmode_enable_hba(hba, 0);
561 				hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
562 			}
563 			pdv->pdv_sd = NULL;
564 			return ret;
565 		}
566 		return 0;
567 	}
568 	spin_unlock_irq(sh->host_lock);
569 
570 	pr_err("pSCSI: Unable to locate %d:%d:%d:%d\n", sh->host_no,
571 		pdv->pdv_channel_id,  pdv->pdv_target_id, pdv->pdv_lun_id);
572 
573 	if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
574 		scsi_host_put(sh);
575 	else if (legacy_mode_enable) {
576 		pscsi_pmode_enable_hba(hba, 0);
577 		hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
578 	}
579 
580 	return -ENODEV;
581 }
582 
583 static void pscsi_free_device(struct se_device *dev)
584 {
585 	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
586 	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
587 	struct scsi_device *sd = pdv->pdv_sd;
588 
589 	if (sd) {
590 		/*
591 		 * Release exclusive pSCSI internal struct block_device claim for
592 		 * struct scsi_device with TYPE_DISK from pscsi_create_type_disk()
593 		 */
594 		if ((sd->type == TYPE_DISK) && pdv->pdv_bd) {
595 			blkdev_put(pdv->pdv_bd,
596 				   FMODE_WRITE|FMODE_READ|FMODE_EXCL);
597 			pdv->pdv_bd = NULL;
598 		}
599 		/*
600 		 * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
601 		 * to struct Scsi_Host now.
602 		 */
603 		if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
604 		    (phv->phv_lld_host != NULL))
605 			scsi_host_put(phv->phv_lld_host);
606 
607 		if ((sd->type == TYPE_DISK) || (sd->type == TYPE_ROM))
608 			scsi_device_put(sd);
609 
610 		pdv->pdv_sd = NULL;
611 	}
612 
613 	kfree(pdv);
614 }
615 
616 static void pscsi_transport_complete(struct se_cmd *cmd, struct scatterlist *sg,
617 				     unsigned char *sense_buffer)
618 {
619 	struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
620 	struct scsi_device *sd = pdv->pdv_sd;
621 	int result;
622 	struct pscsi_plugin_task *pt = cmd->priv;
623 	unsigned char *cdb;
624 	/*
625 	 * Special case for REPORT_LUNs handling where pscsi_plugin_task has
626 	 * not been allocated because TCM is handling the emulation directly.
627 	 */
628 	if (!pt)
629 		return;
630 
631 	cdb = &pt->pscsi_cdb[0];
632 	result = pt->pscsi_result;
633 	/*
634 	 * Hack to make sure that Write-Protect modepage is set if R/O mode is
635 	 * forced.
636 	 */
637 	if (!cmd->se_deve || !cmd->data_length)
638 		goto after_mode_sense;
639 
640 	if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
641 	     (status_byte(result) << 1) == SAM_STAT_GOOD) {
642 		if (cmd->se_deve->lun_flags & TRANSPORT_LUNFLAGS_READ_ONLY) {
643 			unsigned char *buf;
644 
645 			buf = transport_kmap_data_sg(cmd);
646 			if (!buf)
647 				; /* XXX: TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE */
648 
649 			if (cdb[0] == MODE_SENSE_10) {
650 				if (!(buf[3] & 0x80))
651 					buf[3] |= 0x80;
652 			} else {
653 				if (!(buf[2] & 0x80))
654 					buf[2] |= 0x80;
655 			}
656 
657 			transport_kunmap_data_sg(cmd);
658 		}
659 	}
660 after_mode_sense:
661 
662 	if (sd->type != TYPE_TAPE || !cmd->data_length)
663 		goto after_mode_select;
664 
665 	/*
666 	 * Hack to correctly obtain the initiator requested blocksize for
667 	 * TYPE_TAPE.  Since this value is dependent upon each tape media,
668 	 * struct scsi_device->sector_size will not contain the correct value
669 	 * by default, so we go ahead and set it so
670 	 * TRANSPORT(dev)->get_blockdev() returns the correct value to the
671 	 * storage engine.
672 	 */
673 	if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
674 	      (status_byte(result) << 1) == SAM_STAT_GOOD) {
675 		unsigned char *buf;
676 		u16 bdl;
677 		u32 blocksize;
678 
679 		buf = sg_virt(&sg[0]);
680 		if (!buf) {
681 			pr_err("Unable to get buf for scatterlist\n");
682 			goto after_mode_select;
683 		}
684 
685 		if (cdb[0] == MODE_SELECT)
686 			bdl = (buf[3]);
687 		else
688 			bdl = (buf[6] << 8) | (buf[7]);
689 
690 		if (!bdl)
691 			goto after_mode_select;
692 
693 		if (cdb[0] == MODE_SELECT)
694 			blocksize = (buf[9] << 16) | (buf[10] << 8) |
695 					(buf[11]);
696 		else
697 			blocksize = (buf[13] << 16) | (buf[14] << 8) |
698 					(buf[15]);
699 
700 		sd->sector_size = blocksize;
701 	}
702 after_mode_select:
703 
704 	if (sense_buffer && (status_byte(result) & CHECK_CONDITION)) {
705 		memcpy(sense_buffer, pt->pscsi_sense, TRANSPORT_SENSE_BUFFER);
706 		cmd->se_cmd_flags |= SCF_TRANSPORT_TASK_SENSE;
707 	}
708 }
709 
710 enum {
711 	Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
712 	Opt_scsi_lun_id, Opt_err
713 };
714 
715 static match_table_t tokens = {
716 	{Opt_scsi_host_id, "scsi_host_id=%d"},
717 	{Opt_scsi_channel_id, "scsi_channel_id=%d"},
718 	{Opt_scsi_target_id, "scsi_target_id=%d"},
719 	{Opt_scsi_lun_id, "scsi_lun_id=%d"},
720 	{Opt_err, NULL}
721 };
722 
723 static ssize_t pscsi_set_configfs_dev_params(struct se_device *dev,
724 		const char *page, ssize_t count)
725 {
726 	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
727 	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
728 	char *orig, *ptr, *opts;
729 	substring_t args[MAX_OPT_ARGS];
730 	int ret = 0, arg, token;
731 
732 	opts = kstrdup(page, GFP_KERNEL);
733 	if (!opts)
734 		return -ENOMEM;
735 
736 	orig = opts;
737 
738 	while ((ptr = strsep(&opts, ",\n")) != NULL) {
739 		if (!*ptr)
740 			continue;
741 
742 		token = match_token(ptr, tokens, args);
743 		switch (token) {
744 		case Opt_scsi_host_id:
745 			if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
746 				pr_err("PSCSI[%d]: Unable to accept"
747 					" scsi_host_id while phv_mode =="
748 					" PHV_LLD_SCSI_HOST_NO\n",
749 					phv->phv_host_id);
750 				ret = -EINVAL;
751 				goto out;
752 			}
753 			ret = match_int(args, &arg);
754 			if (ret)
755 				goto out;
756 			pdv->pdv_host_id = arg;
757 			pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
758 				" %d\n", phv->phv_host_id, pdv->pdv_host_id);
759 			pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
760 			break;
761 		case Opt_scsi_channel_id:
762 			ret = match_int(args, &arg);
763 			if (ret)
764 				goto out;
765 			pdv->pdv_channel_id = arg;
766 			pr_debug("PSCSI[%d]: Referencing SCSI Channel"
767 				" ID: %d\n",  phv->phv_host_id,
768 				pdv->pdv_channel_id);
769 			pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
770 			break;
771 		case Opt_scsi_target_id:
772 			ret = match_int(args, &arg);
773 			if (ret)
774 				goto out;
775 			pdv->pdv_target_id = arg;
776 			pr_debug("PSCSI[%d]: Referencing SCSI Target"
777 				" ID: %d\n", phv->phv_host_id,
778 				pdv->pdv_target_id);
779 			pdv->pdv_flags |= PDF_HAS_TARGET_ID;
780 			break;
781 		case Opt_scsi_lun_id:
782 			ret = match_int(args, &arg);
783 			if (ret)
784 				goto out;
785 			pdv->pdv_lun_id = arg;
786 			pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
787 				" %d\n", phv->phv_host_id, pdv->pdv_lun_id);
788 			pdv->pdv_flags |= PDF_HAS_LUN_ID;
789 			break;
790 		default:
791 			break;
792 		}
793 	}
794 
795 out:
796 	kfree(orig);
797 	return (!ret) ? count : ret;
798 }
799 
800 static ssize_t pscsi_show_configfs_dev_params(struct se_device *dev, char *b)
801 {
802 	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
803 	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
804 	struct scsi_device *sd = pdv->pdv_sd;
805 	unsigned char host_id[16];
806 	ssize_t bl;
807 	int i;
808 
809 	if (phv->phv_mode == PHV_VIRTUAL_HOST_ID)
810 		snprintf(host_id, 16, "%d", pdv->pdv_host_id);
811 	else
812 		snprintf(host_id, 16, "PHBA Mode");
813 
814 	bl = sprintf(b, "SCSI Device Bus Location:"
815 		" Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
816 		pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
817 		host_id);
818 
819 	if (sd) {
820 		bl += sprintf(b + bl, "        ");
821 		bl += sprintf(b + bl, "Vendor: ");
822 		for (i = 0; i < 8; i++) {
823 			if (ISPRINT(sd->vendor[i]))   /* printable character? */
824 				bl += sprintf(b + bl, "%c", sd->vendor[i]);
825 			else
826 				bl += sprintf(b + bl, " ");
827 		}
828 		bl += sprintf(b + bl, " Model: ");
829 		for (i = 0; i < 16; i++) {
830 			if (ISPRINT(sd->model[i]))   /* printable character ? */
831 				bl += sprintf(b + bl, "%c", sd->model[i]);
832 			else
833 				bl += sprintf(b + bl, " ");
834 		}
835 		bl += sprintf(b + bl, " Rev: ");
836 		for (i = 0; i < 4; i++) {
837 			if (ISPRINT(sd->rev[i]))   /* printable character ? */
838 				bl += sprintf(b + bl, "%c", sd->rev[i]);
839 			else
840 				bl += sprintf(b + bl, " ");
841 		}
842 		bl += sprintf(b + bl, "\n");
843 	}
844 	return bl;
845 }
846 
847 static void pscsi_bi_endio(struct bio *bio, int error)
848 {
849 	bio_put(bio);
850 }
851 
852 static inline struct bio *pscsi_get_bio(int nr_vecs)
853 {
854 	struct bio *bio;
855 	/*
856 	 * Use bio_malloc() following the comment in for bio -> struct request
857 	 * in block/blk-core.c:blk_make_request()
858 	 */
859 	bio = bio_kmalloc(GFP_KERNEL, nr_vecs);
860 	if (!bio) {
861 		pr_err("PSCSI: bio_kmalloc() failed\n");
862 		return NULL;
863 	}
864 	bio->bi_end_io = pscsi_bi_endio;
865 
866 	return bio;
867 }
868 
869 static sense_reason_t
870 pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
871 		enum dma_data_direction data_direction, struct bio **hbio)
872 {
873 	struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
874 	struct bio *bio = NULL, *tbio = NULL;
875 	struct page *page;
876 	struct scatterlist *sg;
877 	u32 data_len = cmd->data_length, i, len, bytes, off;
878 	int nr_pages = (cmd->data_length + sgl[0].offset +
879 			PAGE_SIZE - 1) >> PAGE_SHIFT;
880 	int nr_vecs = 0, rc;
881 	int rw = (data_direction == DMA_TO_DEVICE);
882 
883 	*hbio = NULL;
884 
885 	pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
886 
887 	for_each_sg(sgl, sg, sgl_nents, i) {
888 		page = sg_page(sg);
889 		off = sg->offset;
890 		len = sg->length;
891 
892 		pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
893 			page, len, off);
894 
895 		/*
896 		 * We only have one page of data in each sg element,
897 		 * we can not cross a page boundary.
898 		 */
899 		if (off + len > PAGE_SIZE)
900 			goto fail;
901 
902 		if (len > 0 && data_len > 0) {
903 			bytes = min_t(unsigned int, len, PAGE_SIZE - off);
904 			bytes = min(bytes, data_len);
905 
906 			if (!bio) {
907 				nr_vecs = min_t(int, BIO_MAX_PAGES, nr_pages);
908 				nr_pages -= nr_vecs;
909 				/*
910 				 * Calls bio_kmalloc() and sets bio->bi_end_io()
911 				 */
912 				bio = pscsi_get_bio(nr_vecs);
913 				if (!bio)
914 					goto fail;
915 
916 				if (rw)
917 					bio->bi_rw |= REQ_WRITE;
918 
919 				pr_debug("PSCSI: Allocated bio: %p,"
920 					" dir: %s nr_vecs: %d\n", bio,
921 					(rw) ? "rw" : "r", nr_vecs);
922 				/*
923 				 * Set *hbio pointer to handle the case:
924 				 * nr_pages > BIO_MAX_PAGES, where additional
925 				 * bios need to be added to complete a given
926 				 * command.
927 				 */
928 				if (!*hbio)
929 					*hbio = tbio = bio;
930 				else
931 					tbio = tbio->bi_next = bio;
932 			}
933 
934 			pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
935 				" bio: %p page: %p len: %d off: %d\n", i, bio,
936 				page, len, off);
937 
938 			rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
939 					bio, page, bytes, off);
940 			if (rc != bytes)
941 				goto fail;
942 
943 			pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
944 				bio->bi_vcnt, nr_vecs);
945 
946 			if (bio->bi_vcnt > nr_vecs) {
947 				pr_debug("PSCSI: Reached bio->bi_vcnt max:"
948 					" %d i: %d bio: %p, allocating another"
949 					" bio\n", bio->bi_vcnt, i, bio);
950 				/*
951 				 * Clear the pointer so that another bio will
952 				 * be allocated with pscsi_get_bio() above, the
953 				 * current bio has already been set *tbio and
954 				 * bio->bi_next.
955 				 */
956 				bio = NULL;
957 			}
958 
959 			data_len -= bytes;
960 		}
961 	}
962 
963 	return 0;
964 fail:
965 	while (*hbio) {
966 		bio = *hbio;
967 		*hbio = (*hbio)->bi_next;
968 		bio_endio(bio, 0);	/* XXX: should be error */
969 	}
970 	return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
971 }
972 
973 /*
974  * Clear a lun set in the cdb if the initiator talking to use spoke
975  * and old standards version, as we can't assume the underlying device
976  * won't choke up on it.
977  */
978 static inline void pscsi_clear_cdb_lun(unsigned char *cdb)
979 {
980 	switch (cdb[0]) {
981 	case READ_10: /* SBC - RDProtect */
982 	case READ_12: /* SBC - RDProtect */
983 	case READ_16: /* SBC - RDProtect */
984 	case SEND_DIAGNOSTIC: /* SPC - SELF-TEST Code */
985 	case VERIFY: /* SBC - VRProtect */
986 	case VERIFY_16: /* SBC - VRProtect */
987 	case WRITE_VERIFY: /* SBC - VRProtect */
988 	case WRITE_VERIFY_12: /* SBC - VRProtect */
989 	case MAINTENANCE_IN: /* SPC - Parameter Data Format for SA RTPG */
990 		break;
991 	default:
992 		cdb[1] &= 0x1f; /* clear logical unit number */
993 		break;
994 	}
995 }
996 
997 static sense_reason_t
998 pscsi_parse_cdb(struct se_cmd *cmd)
999 {
1000 	unsigned char *cdb = cmd->t_task_cdb;
1001 
1002 	if (cmd->se_cmd_flags & SCF_BIDI)
1003 		return TCM_UNSUPPORTED_SCSI_OPCODE;
1004 
1005 	pscsi_clear_cdb_lun(cdb);
1006 
1007 	/*
1008 	 * For REPORT LUNS we always need to emulate the response, for everything
1009 	 * else the default for pSCSI is to pass the command to the underlying
1010 	 * LLD / physical hardware.
1011 	 */
1012 	switch (cdb[0]) {
1013 	case REPORT_LUNS:
1014 		cmd->execute_cmd = spc_emulate_report_luns;
1015 		return 0;
1016 	case READ_6:
1017 	case READ_10:
1018 	case READ_12:
1019 	case READ_16:
1020 	case WRITE_6:
1021 	case WRITE_10:
1022 	case WRITE_12:
1023 	case WRITE_16:
1024 	case WRITE_VERIFY:
1025 		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
1026 		/* FALLTHROUGH*/
1027 	default:
1028 		cmd->execute_cmd = pscsi_execute_cmd;
1029 		return 0;
1030 	}
1031 }
1032 
1033 static sense_reason_t
1034 pscsi_execute_cmd(struct se_cmd *cmd)
1035 {
1036 	struct scatterlist *sgl = cmd->t_data_sg;
1037 	u32 sgl_nents = cmd->t_data_nents;
1038 	enum dma_data_direction data_direction = cmd->data_direction;
1039 	struct pscsi_dev_virt *pdv = PSCSI_DEV(cmd->se_dev);
1040 	struct pscsi_plugin_task *pt;
1041 	struct request *req;
1042 	struct bio *hbio;
1043 	sense_reason_t ret;
1044 
1045 	/*
1046 	 * Dynamically alloc cdb space, since it may be larger than
1047 	 * TCM_MAX_COMMAND_SIZE
1048 	 */
1049 	pt = kzalloc(sizeof(*pt) + scsi_command_size(cmd->t_task_cdb), GFP_KERNEL);
1050 	if (!pt) {
1051 		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1052 	}
1053 	cmd->priv = pt;
1054 
1055 	memcpy(pt->pscsi_cdb, cmd->t_task_cdb,
1056 		scsi_command_size(cmd->t_task_cdb));
1057 
1058 	if (!sgl) {
1059 		req = blk_get_request(pdv->pdv_sd->request_queue,
1060 				(data_direction == DMA_TO_DEVICE),
1061 				GFP_KERNEL);
1062 		if (IS_ERR(req)) {
1063 			pr_err("PSCSI: blk_get_request() failed\n");
1064 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1065 			goto fail;
1066 		}
1067 
1068 		blk_rq_set_block_pc(req);
1069 	} else {
1070 		BUG_ON(!cmd->data_length);
1071 
1072 		ret = pscsi_map_sg(cmd, sgl, sgl_nents, data_direction, &hbio);
1073 		if (ret)
1074 			goto fail;
1075 
1076 		req = blk_make_request(pdv->pdv_sd->request_queue, hbio,
1077 				       GFP_KERNEL);
1078 		if (IS_ERR(req)) {
1079 			pr_err("pSCSI: blk_make_request() failed\n");
1080 			ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1081 			goto fail_free_bio;
1082 		}
1083 	}
1084 
1085 	req->end_io = pscsi_req_done;
1086 	req->end_io_data = cmd;
1087 	req->cmd_len = scsi_command_size(pt->pscsi_cdb);
1088 	req->cmd = &pt->pscsi_cdb[0];
1089 	req->sense = &pt->pscsi_sense[0];
1090 	req->sense_len = 0;
1091 	if (pdv->pdv_sd->type == TYPE_DISK)
1092 		req->timeout = PS_TIMEOUT_DISK;
1093 	else
1094 		req->timeout = PS_TIMEOUT_OTHER;
1095 	req->retries = PS_RETRY;
1096 
1097 	blk_execute_rq_nowait(pdv->pdv_sd->request_queue, NULL, req,
1098 			(cmd->sam_task_attr == TCM_HEAD_TAG),
1099 			pscsi_req_done);
1100 
1101 	return 0;
1102 
1103 fail_free_bio:
1104 	while (hbio) {
1105 		struct bio *bio = hbio;
1106 		hbio = hbio->bi_next;
1107 		bio_endio(bio, 0);	/* XXX: should be error */
1108 	}
1109 	ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1110 fail:
1111 	kfree(pt);
1112 	return ret;
1113 }
1114 
1115 /*	pscsi_get_device_type():
1116  *
1117  *
1118  */
1119 static u32 pscsi_get_device_type(struct se_device *dev)
1120 {
1121 	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1122 	struct scsi_device *sd = pdv->pdv_sd;
1123 
1124 	return sd->type;
1125 }
1126 
1127 static sector_t pscsi_get_blocks(struct se_device *dev)
1128 {
1129 	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
1130 
1131 	if (pdv->pdv_bd && pdv->pdv_bd->bd_part)
1132 		return pdv->pdv_bd->bd_part->nr_sects;
1133 
1134 	dump_stack();
1135 	return 0;
1136 }
1137 
1138 static void pscsi_req_done(struct request *req, int uptodate)
1139 {
1140 	struct se_cmd *cmd = req->end_io_data;
1141 	struct pscsi_plugin_task *pt = cmd->priv;
1142 
1143 	pt->pscsi_result = req->errors;
1144 	pt->pscsi_resid = req->resid_len;
1145 
1146 	cmd->scsi_status = status_byte(pt->pscsi_result) << 1;
1147 	if (cmd->scsi_status) {
1148 		pr_debug("PSCSI Status Byte exception at cmd: %p CDB:"
1149 			" 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
1150 			pt->pscsi_result);
1151 	}
1152 
1153 	switch (host_byte(pt->pscsi_result)) {
1154 	case DID_OK:
1155 		target_complete_cmd(cmd, cmd->scsi_status);
1156 		break;
1157 	default:
1158 		pr_debug("PSCSI Host Byte exception at cmd: %p CDB:"
1159 			" 0x%02x Result: 0x%08x\n", cmd, pt->pscsi_cdb[0],
1160 			pt->pscsi_result);
1161 		target_complete_cmd(cmd, SAM_STAT_CHECK_CONDITION);
1162 		break;
1163 	}
1164 
1165 	__blk_put_request(req->q, req);
1166 	kfree(pt);
1167 }
1168 
1169 DEF_TB_DEV_ATTRIB_RO(pscsi, hw_pi_prot_type);
1170 TB_DEV_ATTR_RO(pscsi, hw_pi_prot_type);
1171 
1172 DEF_TB_DEV_ATTRIB_RO(pscsi, hw_block_size);
1173 TB_DEV_ATTR_RO(pscsi, hw_block_size);
1174 
1175 DEF_TB_DEV_ATTRIB_RO(pscsi, hw_max_sectors);
1176 TB_DEV_ATTR_RO(pscsi, hw_max_sectors);
1177 
1178 DEF_TB_DEV_ATTRIB_RO(pscsi, hw_queue_depth);
1179 TB_DEV_ATTR_RO(pscsi, hw_queue_depth);
1180 
1181 static struct configfs_attribute *pscsi_backend_dev_attrs[] = {
1182 	&pscsi_dev_attrib_hw_pi_prot_type.attr,
1183 	&pscsi_dev_attrib_hw_block_size.attr,
1184 	&pscsi_dev_attrib_hw_max_sectors.attr,
1185 	&pscsi_dev_attrib_hw_queue_depth.attr,
1186 	NULL,
1187 };
1188 
1189 static struct se_subsystem_api pscsi_template = {
1190 	.name			= "pscsi",
1191 	.owner			= THIS_MODULE,
1192 	.transport_type		= TRANSPORT_PLUGIN_PHBA_PDEV,
1193 	.attach_hba		= pscsi_attach_hba,
1194 	.detach_hba		= pscsi_detach_hba,
1195 	.pmode_enable_hba	= pscsi_pmode_enable_hba,
1196 	.alloc_device		= pscsi_alloc_device,
1197 	.configure_device	= pscsi_configure_device,
1198 	.free_device		= pscsi_free_device,
1199 	.transport_complete	= pscsi_transport_complete,
1200 	.parse_cdb		= pscsi_parse_cdb,
1201 	.set_configfs_dev_params = pscsi_set_configfs_dev_params,
1202 	.show_configfs_dev_params = pscsi_show_configfs_dev_params,
1203 	.get_device_type	= pscsi_get_device_type,
1204 	.get_blocks		= pscsi_get_blocks,
1205 };
1206 
1207 static int __init pscsi_module_init(void)
1208 {
1209 	struct target_backend_cits *tbc = &pscsi_template.tb_cits;
1210 
1211 	target_core_setup_sub_cits(&pscsi_template);
1212 	tbc->tb_dev_attrib_cit.ct_attrs = pscsi_backend_dev_attrs;
1213 
1214 	return transport_subsystem_register(&pscsi_template);
1215 }
1216 
1217 static void __exit pscsi_module_exit(void)
1218 {
1219 	transport_subsystem_release(&pscsi_template);
1220 }
1221 
1222 MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
1223 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1224 MODULE_LICENSE("GPL");
1225 
1226 module_init(pscsi_module_init);
1227 module_exit(pscsi_module_exit);
1228