xref: /linux/drivers/target/target_core_pscsi.c (revision 60063497a95e716c9a689af3be2687d261f115b4)
1 /*******************************************************************************
2  * Filename:  target_core_pscsi.c
3  *
4  * This file contains the generic target mode <-> Linux SCSI subsystem plugin.
5  *
6  * Copyright (c) 2003, 2004, 2005 PyX Technologies, Inc.
7  * Copyright (c) 2005, 2006, 2007 SBE, Inc.
8  * Copyright (c) 2007-2010 Rising Tide Systems
9  * Copyright (c) 2008-2010 Linux-iSCSI.org
10  *
11  * Nicholas A. Bellinger <nab@kernel.org>
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  * GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software
25  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26  *
27  ******************************************************************************/
28 
29 #include <linux/version.h>
30 #include <linux/string.h>
31 #include <linux/parser.h>
32 #include <linux/timer.h>
33 #include <linux/blkdev.h>
34 #include <linux/blk_types.h>
35 #include <linux/slab.h>
36 #include <linux/spinlock.h>
37 #include <linux/genhd.h>
38 #include <linux/cdrom.h>
39 #include <linux/file.h>
40 #include <scsi/scsi.h>
41 #include <scsi/scsi_device.h>
42 #include <scsi/scsi_cmnd.h>
43 #include <scsi/scsi_host.h>
44 #include <scsi/scsi_tcq.h>
45 
46 #include <target/target_core_base.h>
47 #include <target/target_core_device.h>
48 #include <target/target_core_transport.h>
49 
50 #include "target_core_pscsi.h"
51 
52 #define ISPRINT(a)  ((a >= ' ') && (a <= '~'))
53 
54 static struct se_subsystem_api pscsi_template;
55 
56 static void pscsi_req_done(struct request *, int);
57 
58 /*	pscsi_attach_hba():
59  *
60  * 	pscsi_get_sh() used scsi_host_lookup() to locate struct Scsi_Host.
61  *	from the passed SCSI Host ID.
62  */
63 static int pscsi_attach_hba(struct se_hba *hba, u32 host_id)
64 {
65 	struct pscsi_hba_virt *phv;
66 
67 	phv = kzalloc(sizeof(struct pscsi_hba_virt), GFP_KERNEL);
68 	if (!phv) {
69 		pr_err("Unable to allocate struct pscsi_hba_virt\n");
70 		return -ENOMEM;
71 	}
72 	phv->phv_host_id = host_id;
73 	phv->phv_mode = PHV_VIRUTAL_HOST_ID;
74 
75 	hba->hba_ptr = phv;
76 
77 	pr_debug("CORE_HBA[%d] - TCM SCSI HBA Driver %s on"
78 		" Generic Target Core Stack %s\n", hba->hba_id,
79 		PSCSI_VERSION, TARGET_CORE_MOD_VERSION);
80 	pr_debug("CORE_HBA[%d] - Attached SCSI HBA to Generic\n",
81 	       hba->hba_id);
82 
83 	return 0;
84 }
85 
86 static void pscsi_detach_hba(struct se_hba *hba)
87 {
88 	struct pscsi_hba_virt *phv = hba->hba_ptr;
89 	struct Scsi_Host *scsi_host = phv->phv_lld_host;
90 
91 	if (scsi_host) {
92 		scsi_host_put(scsi_host);
93 
94 		pr_debug("CORE_HBA[%d] - Detached SCSI HBA: %s from"
95 			" Generic Target Core\n", hba->hba_id,
96 			(scsi_host->hostt->name) ? (scsi_host->hostt->name) :
97 			"Unknown");
98 	} else
99 		pr_debug("CORE_HBA[%d] - Detached Virtual SCSI HBA"
100 			" from Generic Target Core\n", hba->hba_id);
101 
102 	kfree(phv);
103 	hba->hba_ptr = NULL;
104 }
105 
106 static int pscsi_pmode_enable_hba(struct se_hba *hba, unsigned long mode_flag)
107 {
108 	struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)hba->hba_ptr;
109 	struct Scsi_Host *sh = phv->phv_lld_host;
110 	/*
111 	 * Release the struct Scsi_Host
112 	 */
113 	if (!mode_flag) {
114 		if (!sh)
115 			return 0;
116 
117 		phv->phv_lld_host = NULL;
118 		phv->phv_mode = PHV_VIRUTAL_HOST_ID;
119 
120 		pr_debug("CORE_HBA[%d] - Disabled pSCSI HBA Passthrough"
121 			" %s\n", hba->hba_id, (sh->hostt->name) ?
122 			(sh->hostt->name) : "Unknown");
123 
124 		scsi_host_put(sh);
125 		return 0;
126 	}
127 	/*
128 	 * Otherwise, locate struct Scsi_Host from the original passed
129 	 * pSCSI Host ID and enable for phba mode
130 	 */
131 	sh = scsi_host_lookup(phv->phv_host_id);
132 	if (IS_ERR(sh)) {
133 		pr_err("pSCSI: Unable to locate SCSI Host for"
134 			" phv_host_id: %d\n", phv->phv_host_id);
135 		return PTR_ERR(sh);
136 	}
137 
138 	phv->phv_lld_host = sh;
139 	phv->phv_mode = PHV_LLD_SCSI_HOST_NO;
140 
141 	pr_debug("CORE_HBA[%d] - Enabled pSCSI HBA Passthrough %s\n",
142 		hba->hba_id, (sh->hostt->name) ? (sh->hostt->name) : "Unknown");
143 
144 	return 1;
145 }
146 
147 static void pscsi_tape_read_blocksize(struct se_device *dev,
148 		struct scsi_device *sdev)
149 {
150 	unsigned char cdb[MAX_COMMAND_SIZE], *buf;
151 	int ret;
152 
153 	buf = kzalloc(12, GFP_KERNEL);
154 	if (!buf)
155 		return;
156 
157 	memset(cdb, 0, MAX_COMMAND_SIZE);
158 	cdb[0] = MODE_SENSE;
159 	cdb[4] = 0x0c; /* 12 bytes */
160 
161 	ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf, 12, NULL,
162 			HZ, 1, NULL);
163 	if (ret)
164 		goto out_free;
165 
166 	/*
167 	 * If MODE_SENSE still returns zero, set the default value to 1024.
168 	 */
169 	sdev->sector_size = (buf[9] << 16) | (buf[10] << 8) | (buf[11]);
170 	if (!sdev->sector_size)
171 		sdev->sector_size = 1024;
172 out_free:
173 	kfree(buf);
174 }
175 
176 static void
177 pscsi_set_inquiry_info(struct scsi_device *sdev, struct t10_wwn *wwn)
178 {
179 	unsigned char *buf;
180 
181 	if (sdev->inquiry_len < INQUIRY_LEN)
182 		return;
183 
184 	buf = sdev->inquiry;
185 	if (!buf)
186 		return;
187 	/*
188 	 * Use sdev->inquiry from drivers/scsi/scsi_scan.c:scsi_alloc_sdev()
189 	 */
190 	memcpy(&wwn->vendor[0], &buf[8], sizeof(wwn->vendor));
191 	memcpy(&wwn->model[0], &buf[16], sizeof(wwn->model));
192 	memcpy(&wwn->revision[0], &buf[32], sizeof(wwn->revision));
193 }
194 
195 static int
196 pscsi_get_inquiry_vpd_serial(struct scsi_device *sdev, struct t10_wwn *wwn)
197 {
198 	unsigned char cdb[MAX_COMMAND_SIZE], *buf;
199 	int ret;
200 
201 	buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
202 	if (!buf)
203 		return -ENOMEM;
204 
205 	memset(cdb, 0, MAX_COMMAND_SIZE);
206 	cdb[0] = INQUIRY;
207 	cdb[1] = 0x01; /* Query VPD */
208 	cdb[2] = 0x80; /* Unit Serial Number */
209 	cdb[3] = (INQUIRY_VPD_SERIAL_LEN >> 8) & 0xff;
210 	cdb[4] = (INQUIRY_VPD_SERIAL_LEN & 0xff);
211 
212 	ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
213 			      INQUIRY_VPD_SERIAL_LEN, NULL, HZ, 1, NULL);
214 	if (ret)
215 		goto out_free;
216 
217 	snprintf(&wwn->unit_serial[0], INQUIRY_VPD_SERIAL_LEN, "%s", &buf[4]);
218 
219 	wwn->t10_sub_dev->su_dev_flags |= SDF_FIRMWARE_VPD_UNIT_SERIAL;
220 
221 	kfree(buf);
222 	return 0;
223 
224 out_free:
225 	kfree(buf);
226 	return -EPERM;
227 }
228 
229 static void
230 pscsi_get_inquiry_vpd_device_ident(struct scsi_device *sdev,
231 		struct t10_wwn *wwn)
232 {
233 	unsigned char cdb[MAX_COMMAND_SIZE], *buf, *page_83;
234 	int ident_len, page_len, off = 4, ret;
235 	struct t10_vpd *vpd;
236 
237 	buf = kzalloc(INQUIRY_VPD_SERIAL_LEN, GFP_KERNEL);
238 	if (!buf)
239 		return;
240 
241 	memset(cdb, 0, MAX_COMMAND_SIZE);
242 	cdb[0] = INQUIRY;
243 	cdb[1] = 0x01; /* Query VPD */
244 	cdb[2] = 0x83; /* Device Identifier */
245 	cdb[3] = (INQUIRY_VPD_DEVICE_IDENTIFIER_LEN >> 8) & 0xff;
246 	cdb[4] = (INQUIRY_VPD_DEVICE_IDENTIFIER_LEN & 0xff);
247 
248 	ret = scsi_execute_req(sdev, cdb, DMA_FROM_DEVICE, buf,
249 			      INQUIRY_VPD_DEVICE_IDENTIFIER_LEN,
250 			      NULL, HZ, 1, NULL);
251 	if (ret)
252 		goto out;
253 
254 	page_len = (buf[2] << 8) | buf[3];
255 	while (page_len > 0) {
256 		/* Grab a pointer to the Identification descriptor */
257 		page_83 = &buf[off];
258 		ident_len = page_83[3];
259 		if (!ident_len) {
260 			pr_err("page_83[3]: identifier"
261 					" length zero!\n");
262 			break;
263 		}
264 		pr_debug("T10 VPD Identifer Length: %d\n", ident_len);
265 
266 		vpd = kzalloc(sizeof(struct t10_vpd), GFP_KERNEL);
267 		if (!vpd) {
268 			pr_err("Unable to allocate memory for"
269 					" struct t10_vpd\n");
270 			goto out;
271 		}
272 		INIT_LIST_HEAD(&vpd->vpd_list);
273 
274 		transport_set_vpd_proto_id(vpd, page_83);
275 		transport_set_vpd_assoc(vpd, page_83);
276 
277 		if (transport_set_vpd_ident_type(vpd, page_83) < 0) {
278 			off += (ident_len + 4);
279 			page_len -= (ident_len + 4);
280 			kfree(vpd);
281 			continue;
282 		}
283 		if (transport_set_vpd_ident(vpd, page_83) < 0) {
284 			off += (ident_len + 4);
285 			page_len -= (ident_len + 4);
286 			kfree(vpd);
287 			continue;
288 		}
289 
290 		list_add_tail(&vpd->vpd_list, &wwn->t10_vpd_list);
291 		off += (ident_len + 4);
292 		page_len -= (ident_len + 4);
293 	}
294 
295 out:
296 	kfree(buf);
297 }
298 
299 /*	pscsi_add_device_to_list():
300  *
301  *
302  */
303 static struct se_device *pscsi_add_device_to_list(
304 	struct se_hba *hba,
305 	struct se_subsystem_dev *se_dev,
306 	struct pscsi_dev_virt *pdv,
307 	struct scsi_device *sd,
308 	int dev_flags)
309 {
310 	struct se_device *dev;
311 	struct se_dev_limits dev_limits;
312 	struct request_queue *q;
313 	struct queue_limits *limits;
314 
315 	memset(&dev_limits, 0, sizeof(struct se_dev_limits));
316 
317 	if (!sd->queue_depth) {
318 		sd->queue_depth = PSCSI_DEFAULT_QUEUEDEPTH;
319 
320 		pr_err("Set broken SCSI Device %d:%d:%d"
321 			" queue_depth to %d\n", sd->channel, sd->id,
322 				sd->lun, sd->queue_depth);
323 	}
324 	/*
325 	 * Setup the local scope queue_limits from struct request_queue->limits
326 	 * to pass into transport_add_device_to_core_hba() as struct se_dev_limits.
327 	 */
328 	q = sd->request_queue;
329 	limits = &dev_limits.limits;
330 	limits->logical_block_size = sd->sector_size;
331 	limits->max_hw_sectors = min_t(int, sd->host->max_sectors, queue_max_hw_sectors(q));
332 	limits->max_sectors = min_t(int, sd->host->max_sectors, queue_max_sectors(q));
333 	dev_limits.hw_queue_depth = sd->queue_depth;
334 	dev_limits.queue_depth = sd->queue_depth;
335 	/*
336 	 * Setup our standard INQUIRY info into se_dev->t10_wwn
337 	 */
338 	pscsi_set_inquiry_info(sd, &se_dev->t10_wwn);
339 
340 	/*
341 	 * Set the pointer pdv->pdv_sd to from passed struct scsi_device,
342 	 * which has already been referenced with Linux SCSI code with
343 	 * scsi_device_get() in this file's pscsi_create_virtdevice().
344 	 *
345 	 * The passthrough operations called by the transport_add_device_*
346 	 * function below will require this pointer to be set for passthroug
347 	 *  ops.
348 	 *
349 	 * For the shutdown case in pscsi_free_device(), this struct
350 	 * scsi_device  reference is released with Linux SCSI code
351 	 * scsi_device_put() and the pdv->pdv_sd cleared.
352 	 */
353 	pdv->pdv_sd = sd;
354 
355 	dev = transport_add_device_to_core_hba(hba, &pscsi_template,
356 				se_dev, dev_flags, pdv,
357 				&dev_limits, NULL, NULL);
358 	if (!dev) {
359 		pdv->pdv_sd = NULL;
360 		return NULL;
361 	}
362 
363 	/*
364 	 * Locate VPD WWN Information used for various purposes within
365 	 * the Storage Engine.
366 	 */
367 	if (!pscsi_get_inquiry_vpd_serial(sd, &se_dev->t10_wwn)) {
368 		/*
369 		 * If VPD Unit Serial returned GOOD status, try
370 		 * VPD Device Identification page (0x83).
371 		 */
372 		pscsi_get_inquiry_vpd_device_ident(sd, &se_dev->t10_wwn);
373 	}
374 
375 	/*
376 	 * For TYPE_TAPE, attempt to determine blocksize with MODE_SENSE.
377 	 */
378 	if (sd->type == TYPE_TAPE)
379 		pscsi_tape_read_blocksize(dev, sd);
380 	return dev;
381 }
382 
383 static void *pscsi_allocate_virtdevice(struct se_hba *hba, const char *name)
384 {
385 	struct pscsi_dev_virt *pdv;
386 
387 	pdv = kzalloc(sizeof(struct pscsi_dev_virt), GFP_KERNEL);
388 	if (!pdv) {
389 		pr_err("Unable to allocate memory for struct pscsi_dev_virt\n");
390 		return NULL;
391 	}
392 	pdv->pdv_se_hba = hba;
393 
394 	pr_debug("PSCSI: Allocated pdv: %p for %s\n", pdv, name);
395 	return pdv;
396 }
397 
398 /*
399  * Called with struct Scsi_Host->host_lock called.
400  */
401 static struct se_device *pscsi_create_type_disk(
402 	struct scsi_device *sd,
403 	struct pscsi_dev_virt *pdv,
404 	struct se_subsystem_dev *se_dev,
405 	struct se_hba *hba)
406 	__releases(sh->host_lock)
407 {
408 	struct se_device *dev;
409 	struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)pdv->pdv_se_hba->hba_ptr;
410 	struct Scsi_Host *sh = sd->host;
411 	struct block_device *bd;
412 	u32 dev_flags = 0;
413 
414 	if (scsi_device_get(sd)) {
415 		pr_err("scsi_device_get() failed for %d:%d:%d:%d\n",
416 			sh->host_no, sd->channel, sd->id, sd->lun);
417 		spin_unlock_irq(sh->host_lock);
418 		return NULL;
419 	}
420 	spin_unlock_irq(sh->host_lock);
421 	/*
422 	 * Claim exclusive struct block_device access to struct scsi_device
423 	 * for TYPE_DISK using supplied udev_path
424 	 */
425 	bd = blkdev_get_by_path(se_dev->se_dev_udev_path,
426 				FMODE_WRITE|FMODE_READ|FMODE_EXCL, pdv);
427 	if (IS_ERR(bd)) {
428 		pr_err("pSCSI: blkdev_get_by_path() failed\n");
429 		scsi_device_put(sd);
430 		return NULL;
431 	}
432 	pdv->pdv_bd = bd;
433 
434 	dev = pscsi_add_device_to_list(hba, se_dev, pdv, sd, dev_flags);
435 	if (!dev) {
436 		blkdev_put(pdv->pdv_bd, FMODE_WRITE|FMODE_READ|FMODE_EXCL);
437 		scsi_device_put(sd);
438 		return NULL;
439 	}
440 	pr_debug("CORE_PSCSI[%d] - Added TYPE_DISK for %d:%d:%d:%d\n",
441 		phv->phv_host_id, sh->host_no, sd->channel, sd->id, sd->lun);
442 
443 	return dev;
444 }
445 
446 /*
447  * Called with struct Scsi_Host->host_lock called.
448  */
449 static struct se_device *pscsi_create_type_rom(
450 	struct scsi_device *sd,
451 	struct pscsi_dev_virt *pdv,
452 	struct se_subsystem_dev *se_dev,
453 	struct se_hba *hba)
454 	__releases(sh->host_lock)
455 {
456 	struct se_device *dev;
457 	struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)pdv->pdv_se_hba->hba_ptr;
458 	struct Scsi_Host *sh = sd->host;
459 	u32 dev_flags = 0;
460 
461 	if (scsi_device_get(sd)) {
462 		pr_err("scsi_device_get() failed for %d:%d:%d:%d\n",
463 			sh->host_no, sd->channel, sd->id, sd->lun);
464 		spin_unlock_irq(sh->host_lock);
465 		return NULL;
466 	}
467 	spin_unlock_irq(sh->host_lock);
468 
469 	dev = pscsi_add_device_to_list(hba, se_dev, pdv, sd, dev_flags);
470 	if (!dev) {
471 		scsi_device_put(sd);
472 		return NULL;
473 	}
474 	pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%d\n",
475 		phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
476 		sd->channel, sd->id, sd->lun);
477 
478 	return dev;
479 }
480 
481 /*
482  *Called with struct Scsi_Host->host_lock called.
483  */
484 static struct se_device *pscsi_create_type_other(
485 	struct scsi_device *sd,
486 	struct pscsi_dev_virt *pdv,
487 	struct se_subsystem_dev *se_dev,
488 	struct se_hba *hba)
489 	__releases(sh->host_lock)
490 {
491 	struct se_device *dev;
492 	struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)pdv->pdv_se_hba->hba_ptr;
493 	struct Scsi_Host *sh = sd->host;
494 	u32 dev_flags = 0;
495 
496 	spin_unlock_irq(sh->host_lock);
497 	dev = pscsi_add_device_to_list(hba, se_dev, pdv, sd, dev_flags);
498 	if (!dev)
499 		return NULL;
500 
501 	pr_debug("CORE_PSCSI[%d] - Added Type: %s for %d:%d:%d:%d\n",
502 		phv->phv_host_id, scsi_device_type(sd->type), sh->host_no,
503 		sd->channel, sd->id, sd->lun);
504 
505 	return dev;
506 }
507 
508 static struct se_device *pscsi_create_virtdevice(
509 	struct se_hba *hba,
510 	struct se_subsystem_dev *se_dev,
511 	void *p)
512 {
513 	struct pscsi_dev_virt *pdv = (struct pscsi_dev_virt *)p;
514 	struct se_device *dev;
515 	struct scsi_device *sd;
516 	struct pscsi_hba_virt *phv = (struct pscsi_hba_virt *)hba->hba_ptr;
517 	struct Scsi_Host *sh = phv->phv_lld_host;
518 	int legacy_mode_enable = 0;
519 
520 	if (!pdv) {
521 		pr_err("Unable to locate struct pscsi_dev_virt"
522 				" parameter\n");
523 		return ERR_PTR(-EINVAL);
524 	}
525 	/*
526 	 * If not running in PHV_LLD_SCSI_HOST_NO mode, locate the
527 	 * struct Scsi_Host we will need to bring the TCM/pSCSI object online
528 	 */
529 	if (!sh) {
530 		if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
531 			pr_err("pSCSI: Unable to locate struct"
532 				" Scsi_Host for PHV_LLD_SCSI_HOST_NO\n");
533 			return ERR_PTR(-ENODEV);
534 		}
535 		/*
536 		 * For the newer PHV_VIRUTAL_HOST_ID struct scsi_device
537 		 * reference, we enforce that udev_path has been set
538 		 */
539 		if (!(se_dev->su_dev_flags & SDF_USING_UDEV_PATH)) {
540 			pr_err("pSCSI: udev_path attribute has not"
541 				" been set before ENABLE=1\n");
542 			return ERR_PTR(-EINVAL);
543 		}
544 		/*
545 		 * If no scsi_host_id= was passed for PHV_VIRUTAL_HOST_ID,
546 		 * use the original TCM hba ID to reference Linux/SCSI Host No
547 		 * and enable for PHV_LLD_SCSI_HOST_NO mode.
548 		 */
549 		if (!(pdv->pdv_flags & PDF_HAS_VIRT_HOST_ID)) {
550 			spin_lock(&hba->device_lock);
551 			if (!list_empty(&hba->hba_dev_list)) {
552 				pr_err("pSCSI: Unable to set hba_mode"
553 					" with active devices\n");
554 				spin_unlock(&hba->device_lock);
555 				return ERR_PTR(-EEXIST);
556 			}
557 			spin_unlock(&hba->device_lock);
558 
559 			if (pscsi_pmode_enable_hba(hba, 1) != 1)
560 				return ERR_PTR(-ENODEV);
561 
562 			legacy_mode_enable = 1;
563 			hba->hba_flags |= HBA_FLAGS_PSCSI_MODE;
564 			sh = phv->phv_lld_host;
565 		} else {
566 			sh = scsi_host_lookup(pdv->pdv_host_id);
567 			if (IS_ERR(sh)) {
568 				pr_err("pSCSI: Unable to locate"
569 					" pdv_host_id: %d\n", pdv->pdv_host_id);
570 				return (struct se_device *) sh;
571 			}
572 		}
573 	} else {
574 		if (phv->phv_mode == PHV_VIRUTAL_HOST_ID) {
575 			pr_err("pSCSI: PHV_VIRUTAL_HOST_ID set while"
576 				" struct Scsi_Host exists\n");
577 			return ERR_PTR(-EEXIST);
578 		}
579 	}
580 
581 	spin_lock_irq(sh->host_lock);
582 	list_for_each_entry(sd, &sh->__devices, siblings) {
583 		if ((pdv->pdv_channel_id != sd->channel) ||
584 		    (pdv->pdv_target_id != sd->id) ||
585 		    (pdv->pdv_lun_id != sd->lun))
586 			continue;
587 		/*
588 		 * Functions will release the held struct scsi_host->host_lock
589 		 * before calling calling pscsi_add_device_to_list() to register
590 		 * struct scsi_device with target_core_mod.
591 		 */
592 		switch (sd->type) {
593 		case TYPE_DISK:
594 			dev = pscsi_create_type_disk(sd, pdv, se_dev, hba);
595 			break;
596 		case TYPE_ROM:
597 			dev = pscsi_create_type_rom(sd, pdv, se_dev, hba);
598 			break;
599 		default:
600 			dev = pscsi_create_type_other(sd, pdv, se_dev, hba);
601 			break;
602 		}
603 
604 		if (!dev) {
605 			if (phv->phv_mode == PHV_VIRUTAL_HOST_ID)
606 				scsi_host_put(sh);
607 			else if (legacy_mode_enable) {
608 				pscsi_pmode_enable_hba(hba, 0);
609 				hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
610 			}
611 			pdv->pdv_sd = NULL;
612 			return ERR_PTR(-ENODEV);
613 		}
614 		return dev;
615 	}
616 	spin_unlock_irq(sh->host_lock);
617 
618 	pr_err("pSCSI: Unable to locate %d:%d:%d:%d\n", sh->host_no,
619 		pdv->pdv_channel_id,  pdv->pdv_target_id, pdv->pdv_lun_id);
620 
621 	if (phv->phv_mode == PHV_VIRUTAL_HOST_ID)
622 		scsi_host_put(sh);
623 	else if (legacy_mode_enable) {
624 		pscsi_pmode_enable_hba(hba, 0);
625 		hba->hba_flags &= ~HBA_FLAGS_PSCSI_MODE;
626 	}
627 
628 	return ERR_PTR(-ENODEV);
629 }
630 
631 /*	pscsi_free_device(): (Part of se_subsystem_api_t template)
632  *
633  *
634  */
635 static void pscsi_free_device(void *p)
636 {
637 	struct pscsi_dev_virt *pdv = p;
638 	struct pscsi_hba_virt *phv = pdv->pdv_se_hba->hba_ptr;
639 	struct scsi_device *sd = pdv->pdv_sd;
640 
641 	if (sd) {
642 		/*
643 		 * Release exclusive pSCSI internal struct block_device claim for
644 		 * struct scsi_device with TYPE_DISK from pscsi_create_type_disk()
645 		 */
646 		if ((sd->type == TYPE_DISK) && pdv->pdv_bd) {
647 			blkdev_put(pdv->pdv_bd,
648 				   FMODE_WRITE|FMODE_READ|FMODE_EXCL);
649 			pdv->pdv_bd = NULL;
650 		}
651 		/*
652 		 * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
653 		 * to struct Scsi_Host now.
654 		 */
655 		if ((phv->phv_mode == PHV_LLD_SCSI_HOST_NO) &&
656 		    (phv->phv_lld_host != NULL))
657 			scsi_host_put(phv->phv_lld_host);
658 
659 		if ((sd->type == TYPE_DISK) || (sd->type == TYPE_ROM))
660 			scsi_device_put(sd);
661 
662 		pdv->pdv_sd = NULL;
663 	}
664 
665 	kfree(pdv);
666 }
667 
668 static inline struct pscsi_plugin_task *PSCSI_TASK(struct se_task *task)
669 {
670 	return container_of(task, struct pscsi_plugin_task, pscsi_task);
671 }
672 
673 
674 /*	pscsi_transport_complete():
675  *
676  *
677  */
678 static int pscsi_transport_complete(struct se_task *task)
679 {
680 	struct pscsi_dev_virt *pdv = task->se_dev->dev_ptr;
681 	struct scsi_device *sd = pdv->pdv_sd;
682 	int result;
683 	struct pscsi_plugin_task *pt = PSCSI_TASK(task);
684 	unsigned char *cdb = &pt->pscsi_cdb[0];
685 
686 	result = pt->pscsi_result;
687 	/*
688 	 * Hack to make sure that Write-Protect modepage is set if R/O mode is
689 	 * forced.
690 	 */
691 	if (((cdb[0] == MODE_SENSE) || (cdb[0] == MODE_SENSE_10)) &&
692 	     (status_byte(result) << 1) == SAM_STAT_GOOD) {
693 		if (!task->task_se_cmd->se_deve)
694 			goto after_mode_sense;
695 
696 		if (task->task_se_cmd->se_deve->lun_flags &
697 				TRANSPORT_LUNFLAGS_READ_ONLY) {
698 			unsigned char *buf = transport_kmap_first_data_page(task->task_se_cmd);
699 
700 			if (cdb[0] == MODE_SENSE_10) {
701 				if (!(buf[3] & 0x80))
702 					buf[3] |= 0x80;
703 			} else {
704 				if (!(buf[2] & 0x80))
705 					buf[2] |= 0x80;
706 			}
707 
708 			transport_kunmap_first_data_page(task->task_se_cmd);
709 		}
710 	}
711 after_mode_sense:
712 
713 	if (sd->type != TYPE_TAPE)
714 		goto after_mode_select;
715 
716 	/*
717 	 * Hack to correctly obtain the initiator requested blocksize for
718 	 * TYPE_TAPE.  Since this value is dependent upon each tape media,
719 	 * struct scsi_device->sector_size will not contain the correct value
720 	 * by default, so we go ahead and set it so
721 	 * TRANSPORT(dev)->get_blockdev() returns the correct value to the
722 	 * storage engine.
723 	 */
724 	if (((cdb[0] == MODE_SELECT) || (cdb[0] == MODE_SELECT_10)) &&
725 	      (status_byte(result) << 1) == SAM_STAT_GOOD) {
726 		unsigned char *buf;
727 		struct scatterlist *sg = task->task_sg;
728 		u16 bdl;
729 		u32 blocksize;
730 
731 		buf = sg_virt(&sg[0]);
732 		if (!buf) {
733 			pr_err("Unable to get buf for scatterlist\n");
734 			goto after_mode_select;
735 		}
736 
737 		if (cdb[0] == MODE_SELECT)
738 			bdl = (buf[3]);
739 		else
740 			bdl = (buf[6] << 8) | (buf[7]);
741 
742 		if (!bdl)
743 			goto after_mode_select;
744 
745 		if (cdb[0] == MODE_SELECT)
746 			blocksize = (buf[9] << 16) | (buf[10] << 8) |
747 					(buf[11]);
748 		else
749 			blocksize = (buf[13] << 16) | (buf[14] << 8) |
750 					(buf[15]);
751 
752 		sd->sector_size = blocksize;
753 	}
754 after_mode_select:
755 
756 	if (status_byte(result) & CHECK_CONDITION)
757 		return 1;
758 
759 	return 0;
760 }
761 
762 static struct se_task *
763 pscsi_alloc_task(unsigned char *cdb)
764 {
765 	struct pscsi_plugin_task *pt;
766 
767 	/*
768 	 * Dynamically alloc cdb space, since it may be larger than
769 	 * TCM_MAX_COMMAND_SIZE
770 	 */
771 	pt = kzalloc(sizeof(*pt) + scsi_command_size(cdb), GFP_KERNEL);
772 	if (!pt) {
773 		pr_err("Unable to allocate struct pscsi_plugin_task\n");
774 		return NULL;
775 	}
776 
777 	return &pt->pscsi_task;
778 }
779 
780 static inline void pscsi_blk_init_request(
781 	struct se_task *task,
782 	struct pscsi_plugin_task *pt,
783 	struct request *req,
784 	int bidi_read)
785 {
786 	/*
787 	 * Defined as "scsi command" in include/linux/blkdev.h.
788 	 */
789 	req->cmd_type = REQ_TYPE_BLOCK_PC;
790 	/*
791 	 * For the extra BIDI-COMMAND READ struct request we do not
792 	 * need to setup the remaining structure members
793 	 */
794 	if (bidi_read)
795 		return;
796 	/*
797 	 * Setup the done function pointer for struct request,
798 	 * also set the end_io_data pointer.to struct se_task.
799 	 */
800 	req->end_io = pscsi_req_done;
801 	req->end_io_data = task;
802 	/*
803 	 * Load the referenced struct se_task's SCSI CDB into
804 	 * include/linux/blkdev.h:struct request->cmd
805 	 */
806 	req->cmd_len = scsi_command_size(pt->pscsi_cdb);
807 	req->cmd = &pt->pscsi_cdb[0];
808 	/*
809 	 * Setup pointer for outgoing sense data.
810 	 */
811 	req->sense = &pt->pscsi_sense[0];
812 	req->sense_len = 0;
813 }
814 
815 /*
816  * Used for pSCSI data payloads for all *NON* SCF_SCSI_DATA_SG_IO_CDB
817 */
818 static int pscsi_blk_get_request(struct se_task *task)
819 {
820 	struct pscsi_plugin_task *pt = PSCSI_TASK(task);
821 	struct pscsi_dev_virt *pdv = task->se_dev->dev_ptr;
822 
823 	pt->pscsi_req = blk_get_request(pdv->pdv_sd->request_queue,
824 			(task->task_data_direction == DMA_TO_DEVICE),
825 			GFP_KERNEL);
826 	if (!pt->pscsi_req || IS_ERR(pt->pscsi_req)) {
827 		pr_err("PSCSI: blk_get_request() failed: %ld\n",
828 				IS_ERR(pt->pscsi_req));
829 		return PYX_TRANSPORT_LU_COMM_FAILURE;
830 	}
831 	/*
832 	 * Setup the newly allocated struct request for REQ_TYPE_BLOCK_PC,
833 	 * and setup rq callback, CDB and sense.
834 	 */
835 	pscsi_blk_init_request(task, pt, pt->pscsi_req, 0);
836 	return 0;
837 }
838 
839 /*      pscsi_do_task(): (Part of se_subsystem_api_t template)
840  *
841  *
842  */
843 static int pscsi_do_task(struct se_task *task)
844 {
845 	struct pscsi_plugin_task *pt = PSCSI_TASK(task);
846 	struct pscsi_dev_virt *pdv = task->se_dev->dev_ptr;
847 	/*
848 	 * Set the struct request->timeout value based on peripheral
849 	 * device type from SCSI.
850 	 */
851 	if (pdv->pdv_sd->type == TYPE_DISK)
852 		pt->pscsi_req->timeout = PS_TIMEOUT_DISK;
853 	else
854 		pt->pscsi_req->timeout = PS_TIMEOUT_OTHER;
855 
856 	pt->pscsi_req->retries = PS_RETRY;
857 	/*
858 	 * Queue the struct request into the struct scsi_device->request_queue.
859 	 * Also check for HEAD_OF_QUEUE SAM TASK attr from received se_cmd
860 	 * descriptor
861 	 */
862 	blk_execute_rq_nowait(pdv->pdv_sd->request_queue, NULL, pt->pscsi_req,
863 			(task->task_se_cmd->sam_task_attr == MSG_HEAD_TAG),
864 			pscsi_req_done);
865 
866 	return PYX_TRANSPORT_SENT_TO_TRANSPORT;
867 }
868 
869 static void pscsi_free_task(struct se_task *task)
870 {
871 	struct pscsi_plugin_task *pt = PSCSI_TASK(task);
872 
873 	/*
874 	 * We do not release the bio(s) here associated with this task, as
875 	 * this is handled by bio_put() and pscsi_bi_endio().
876 	 */
877 	kfree(pt);
878 }
879 
880 enum {
881 	Opt_scsi_host_id, Opt_scsi_channel_id, Opt_scsi_target_id,
882 	Opt_scsi_lun_id, Opt_err
883 };
884 
885 static match_table_t tokens = {
886 	{Opt_scsi_host_id, "scsi_host_id=%d"},
887 	{Opt_scsi_channel_id, "scsi_channel_id=%d"},
888 	{Opt_scsi_target_id, "scsi_target_id=%d"},
889 	{Opt_scsi_lun_id, "scsi_lun_id=%d"},
890 	{Opt_err, NULL}
891 };
892 
893 static ssize_t pscsi_set_configfs_dev_params(struct se_hba *hba,
894 	struct se_subsystem_dev *se_dev,
895 	const char *page,
896 	ssize_t count)
897 {
898 	struct pscsi_dev_virt *pdv = se_dev->se_dev_su_ptr;
899 	struct pscsi_hba_virt *phv = hba->hba_ptr;
900 	char *orig, *ptr, *opts;
901 	substring_t args[MAX_OPT_ARGS];
902 	int ret = 0, arg, token;
903 
904 	opts = kstrdup(page, GFP_KERNEL);
905 	if (!opts)
906 		return -ENOMEM;
907 
908 	orig = opts;
909 
910 	while ((ptr = strsep(&opts, ",")) != NULL) {
911 		if (!*ptr)
912 			continue;
913 
914 		token = match_token(ptr, tokens, args);
915 		switch (token) {
916 		case Opt_scsi_host_id:
917 			if (phv->phv_mode == PHV_LLD_SCSI_HOST_NO) {
918 				pr_err("PSCSI[%d]: Unable to accept"
919 					" scsi_host_id while phv_mode =="
920 					" PHV_LLD_SCSI_HOST_NO\n",
921 					phv->phv_host_id);
922 				ret = -EINVAL;
923 				goto out;
924 			}
925 			match_int(args, &arg);
926 			pdv->pdv_host_id = arg;
927 			pr_debug("PSCSI[%d]: Referencing SCSI Host ID:"
928 				" %d\n", phv->phv_host_id, pdv->pdv_host_id);
929 			pdv->pdv_flags |= PDF_HAS_VIRT_HOST_ID;
930 			break;
931 		case Opt_scsi_channel_id:
932 			match_int(args, &arg);
933 			pdv->pdv_channel_id = arg;
934 			pr_debug("PSCSI[%d]: Referencing SCSI Channel"
935 				" ID: %d\n",  phv->phv_host_id,
936 				pdv->pdv_channel_id);
937 			pdv->pdv_flags |= PDF_HAS_CHANNEL_ID;
938 			break;
939 		case Opt_scsi_target_id:
940 			match_int(args, &arg);
941 			pdv->pdv_target_id = arg;
942 			pr_debug("PSCSI[%d]: Referencing SCSI Target"
943 				" ID: %d\n", phv->phv_host_id,
944 				pdv->pdv_target_id);
945 			pdv->pdv_flags |= PDF_HAS_TARGET_ID;
946 			break;
947 		case Opt_scsi_lun_id:
948 			match_int(args, &arg);
949 			pdv->pdv_lun_id = arg;
950 			pr_debug("PSCSI[%d]: Referencing SCSI LUN ID:"
951 				" %d\n", phv->phv_host_id, pdv->pdv_lun_id);
952 			pdv->pdv_flags |= PDF_HAS_LUN_ID;
953 			break;
954 		default:
955 			break;
956 		}
957 	}
958 
959 out:
960 	kfree(orig);
961 	return (!ret) ? count : ret;
962 }
963 
964 static ssize_t pscsi_check_configfs_dev_params(
965 	struct se_hba *hba,
966 	struct se_subsystem_dev *se_dev)
967 {
968 	struct pscsi_dev_virt *pdv = se_dev->se_dev_su_ptr;
969 
970 	if (!(pdv->pdv_flags & PDF_HAS_CHANNEL_ID) ||
971 	    !(pdv->pdv_flags & PDF_HAS_TARGET_ID) ||
972 	    !(pdv->pdv_flags & PDF_HAS_LUN_ID)) {
973 		pr_err("Missing scsi_channel_id=, scsi_target_id= and"
974 			" scsi_lun_id= parameters\n");
975 		return -EINVAL;
976 	}
977 
978 	return 0;
979 }
980 
981 static ssize_t pscsi_show_configfs_dev_params(struct se_hba *hba,
982 					      struct se_subsystem_dev *se_dev,
983 					      char *b)
984 {
985 	struct pscsi_hba_virt *phv = hba->hba_ptr;
986         struct pscsi_dev_virt *pdv = se_dev->se_dev_su_ptr;
987 	struct scsi_device *sd = pdv->pdv_sd;
988 	unsigned char host_id[16];
989 	ssize_t bl;
990 	int i;
991 
992 	if (phv->phv_mode == PHV_VIRUTAL_HOST_ID)
993 		snprintf(host_id, 16, "%d", pdv->pdv_host_id);
994 	else
995 		snprintf(host_id, 16, "PHBA Mode");
996 
997 	bl = sprintf(b, "SCSI Device Bus Location:"
998 		" Channel ID: %d Target ID: %d LUN: %d Host ID: %s\n",
999 		pdv->pdv_channel_id, pdv->pdv_target_id, pdv->pdv_lun_id,
1000 		host_id);
1001 
1002 	if (sd) {
1003 		bl += sprintf(b + bl, "        ");
1004 		bl += sprintf(b + bl, "Vendor: ");
1005 		for (i = 0; i < 8; i++) {
1006 			if (ISPRINT(sd->vendor[i]))   /* printable character? */
1007 				bl += sprintf(b + bl, "%c", sd->vendor[i]);
1008 			else
1009 				bl += sprintf(b + bl, " ");
1010 		}
1011 		bl += sprintf(b + bl, " Model: ");
1012 		for (i = 0; i < 16; i++) {
1013 			if (ISPRINT(sd->model[i]))   /* printable character ? */
1014 				bl += sprintf(b + bl, "%c", sd->model[i]);
1015 			else
1016 				bl += sprintf(b + bl, " ");
1017 		}
1018 		bl += sprintf(b + bl, " Rev: ");
1019 		for (i = 0; i < 4; i++) {
1020 			if (ISPRINT(sd->rev[i]))   /* printable character ? */
1021 				bl += sprintf(b + bl, "%c", sd->rev[i]);
1022 			else
1023 				bl += sprintf(b + bl, " ");
1024 		}
1025 		bl += sprintf(b + bl, "\n");
1026 	}
1027 	return bl;
1028 }
1029 
1030 static void pscsi_bi_endio(struct bio *bio, int error)
1031 {
1032 	bio_put(bio);
1033 }
1034 
1035 static inline struct bio *pscsi_get_bio(int sg_num)
1036 {
1037 	struct bio *bio;
1038 	/*
1039 	 * Use bio_malloc() following the comment in for bio -> struct request
1040 	 * in block/blk-core.c:blk_make_request()
1041 	 */
1042 	bio = bio_kmalloc(GFP_KERNEL, sg_num);
1043 	if (!bio) {
1044 		pr_err("PSCSI: bio_kmalloc() failed\n");
1045 		return NULL;
1046 	}
1047 	bio->bi_end_io = pscsi_bi_endio;
1048 
1049 	return bio;
1050 }
1051 
1052 static int __pscsi_map_SG(
1053 	struct se_task *task,
1054 	struct scatterlist *task_sg,
1055 	u32 task_sg_num,
1056 	int bidi_read)
1057 {
1058 	struct pscsi_plugin_task *pt = PSCSI_TASK(task);
1059 	struct pscsi_dev_virt *pdv = task->se_dev->dev_ptr;
1060 	struct bio *bio = NULL, *hbio = NULL, *tbio = NULL;
1061 	struct page *page;
1062 	struct scatterlist *sg;
1063 	u32 data_len = task->task_size, i, len, bytes, off;
1064 	int nr_pages = (task->task_size + task_sg[0].offset +
1065 			PAGE_SIZE - 1) >> PAGE_SHIFT;
1066 	int nr_vecs = 0, rc, ret = PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES;
1067 	int rw = (task->task_data_direction == DMA_TO_DEVICE);
1068 
1069 	if (!task->task_size)
1070 		return 0;
1071 	/*
1072 	 * For SCF_SCSI_DATA_SG_IO_CDB, Use fs/bio.c:bio_add_page() to setup
1073 	 * the bio_vec maplist from task->task_sg ->
1074 	 * struct scatterlist memory.  The struct se_task->task_sg[] currently needs
1075 	 * to be attached to struct bios for submission to Linux/SCSI using
1076 	 * struct request to struct scsi_device->request_queue.
1077 	 *
1078 	 * Note that this will be changing post v2.6.28 as Target_Core_Mod/pSCSI
1079 	 * is ported to upstream SCSI passthrough functionality that accepts
1080 	 * struct scatterlist->page_link or struct page as a paraemeter.
1081 	 */
1082 	pr_debug("PSCSI: nr_pages: %d\n", nr_pages);
1083 
1084 	for_each_sg(task_sg, sg, task_sg_num, i) {
1085 		page = sg_page(sg);
1086 		off = sg->offset;
1087 		len = sg->length;
1088 
1089 		pr_debug("PSCSI: i: %d page: %p len: %d off: %d\n", i,
1090 			page, len, off);
1091 
1092 		while (len > 0 && data_len > 0) {
1093 			bytes = min_t(unsigned int, len, PAGE_SIZE - off);
1094 			bytes = min(bytes, data_len);
1095 
1096 			if (!bio) {
1097 				nr_vecs = min_t(int, BIO_MAX_PAGES, nr_pages);
1098 				nr_pages -= nr_vecs;
1099 				/*
1100 				 * Calls bio_kmalloc() and sets bio->bi_end_io()
1101 				 */
1102 				bio = pscsi_get_bio(nr_vecs);
1103 				if (!bio)
1104 					goto fail;
1105 
1106 				if (rw)
1107 					bio->bi_rw |= REQ_WRITE;
1108 
1109 				pr_debug("PSCSI: Allocated bio: %p,"
1110 					" dir: %s nr_vecs: %d\n", bio,
1111 					(rw) ? "rw" : "r", nr_vecs);
1112 				/*
1113 				 * Set *hbio pointer to handle the case:
1114 				 * nr_pages > BIO_MAX_PAGES, where additional
1115 				 * bios need to be added to complete a given
1116 				 * struct se_task
1117 				 */
1118 				if (!hbio)
1119 					hbio = tbio = bio;
1120 				else
1121 					tbio = tbio->bi_next = bio;
1122 			}
1123 
1124 			pr_debug("PSCSI: Calling bio_add_pc_page() i: %d"
1125 				" bio: %p page: %p len: %d off: %d\n", i, bio,
1126 				page, len, off);
1127 
1128 			rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
1129 					bio, page, bytes, off);
1130 			if (rc != bytes)
1131 				goto fail;
1132 
1133 			pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
1134 				bio->bi_vcnt, nr_vecs);
1135 
1136 			if (bio->bi_vcnt > nr_vecs) {
1137 				pr_debug("PSCSI: Reached bio->bi_vcnt max:"
1138 					" %d i: %d bio: %p, allocating another"
1139 					" bio\n", bio->bi_vcnt, i, bio);
1140 				/*
1141 				 * Clear the pointer so that another bio will
1142 				 * be allocated with pscsi_get_bio() above, the
1143 				 * current bio has already been set *tbio and
1144 				 * bio->bi_next.
1145 				 */
1146 				bio = NULL;
1147 			}
1148 
1149 			page++;
1150 			len -= bytes;
1151 			data_len -= bytes;
1152 			off = 0;
1153 		}
1154 	}
1155 	/*
1156 	 * Setup the primary pt->pscsi_req used for non BIDI and BIDI-COMMAND
1157 	 * primary SCSI WRITE poayload mapped for struct se_task->task_sg[]
1158 	 */
1159 	if (!bidi_read) {
1160 		/*
1161 		 * Starting with v2.6.31, call blk_make_request() passing in *hbio to
1162 		 * allocate the pSCSI task a struct request.
1163 		 */
1164 		pt->pscsi_req = blk_make_request(pdv->pdv_sd->request_queue,
1165 					hbio, GFP_KERNEL);
1166 		if (!pt->pscsi_req) {
1167 			pr_err("pSCSI: blk_make_request() failed\n");
1168 			goto fail;
1169 		}
1170 		/*
1171 		 * Setup the newly allocated struct request for REQ_TYPE_BLOCK_PC,
1172 		 * and setup rq callback, CDB and sense.
1173 		 */
1174 		pscsi_blk_init_request(task, pt, pt->pscsi_req, 0);
1175 
1176 		return task->task_sg_nents;
1177 	}
1178 	/*
1179 	 * Setup the secondary pt->pscsi_req->next_rq used for the extra BIDI-COMMAND
1180 	 * SCSI READ paylaod mapped for struct se_task->task_sg_bidi[]
1181 	 */
1182 	pt->pscsi_req->next_rq = blk_make_request(pdv->pdv_sd->request_queue,
1183 					hbio, GFP_KERNEL);
1184 	if (!pt->pscsi_req->next_rq) {
1185 		pr_err("pSCSI: blk_make_request() failed for BIDI\n");
1186 		goto fail;
1187 	}
1188 	pscsi_blk_init_request(task, pt, pt->pscsi_req->next_rq, 1);
1189 
1190 	return task->task_sg_nents;
1191 fail:
1192 	while (hbio) {
1193 		bio = hbio;
1194 		hbio = hbio->bi_next;
1195 		bio->bi_next = NULL;
1196 		bio_endio(bio, 0);
1197 	}
1198 	return ret;
1199 }
1200 
1201 /*
1202  * pSCSI maps both ->map_control_SG() and ->map_data_SG() to a single call.
1203  */
1204 static int pscsi_map_SG(struct se_task *task)
1205 {
1206 	int ret;
1207 
1208 	/*
1209 	 * Setup the main struct request for the task->task_sg[] payload
1210 	 */
1211 
1212 	ret = __pscsi_map_SG(task, task->task_sg, task->task_sg_nents, 0);
1213 	if (ret >= 0 && task->task_sg_bidi) {
1214 		/*
1215 		 * If present, set up the extra BIDI-COMMAND SCSI READ
1216 		 * struct request and payload.
1217 		 */
1218 		ret = __pscsi_map_SG(task, task->task_sg_bidi,
1219 					task->task_sg_nents, 1);
1220 	}
1221 
1222 	if (ret < 0)
1223 		return PYX_TRANSPORT_LU_COMM_FAILURE;
1224 	return 0;
1225 }
1226 
1227 static int pscsi_CDB_none(struct se_task *task)
1228 {
1229 	return pscsi_blk_get_request(task);
1230 }
1231 
1232 /*	pscsi_get_cdb():
1233  *
1234  *
1235  */
1236 static unsigned char *pscsi_get_cdb(struct se_task *task)
1237 {
1238 	struct pscsi_plugin_task *pt = PSCSI_TASK(task);
1239 
1240 	return pt->pscsi_cdb;
1241 }
1242 
1243 /*	pscsi_get_sense_buffer():
1244  *
1245  *
1246  */
1247 static unsigned char *pscsi_get_sense_buffer(struct se_task *task)
1248 {
1249 	struct pscsi_plugin_task *pt = PSCSI_TASK(task);
1250 
1251 	return (unsigned char *)&pt->pscsi_sense[0];
1252 }
1253 
1254 /*	pscsi_get_device_rev():
1255  *
1256  *
1257  */
1258 static u32 pscsi_get_device_rev(struct se_device *dev)
1259 {
1260 	struct pscsi_dev_virt *pdv = dev->dev_ptr;
1261 	struct scsi_device *sd = pdv->pdv_sd;
1262 
1263 	return (sd->scsi_level - 1) ? sd->scsi_level - 1 : 1;
1264 }
1265 
1266 /*	pscsi_get_device_type():
1267  *
1268  *
1269  */
1270 static u32 pscsi_get_device_type(struct se_device *dev)
1271 {
1272 	struct pscsi_dev_virt *pdv = dev->dev_ptr;
1273 	struct scsi_device *sd = pdv->pdv_sd;
1274 
1275 	return sd->type;
1276 }
1277 
1278 static sector_t pscsi_get_blocks(struct se_device *dev)
1279 {
1280 	struct pscsi_dev_virt *pdv = dev->dev_ptr;
1281 
1282 	if (pdv->pdv_bd && pdv->pdv_bd->bd_part)
1283 		return pdv->pdv_bd->bd_part->nr_sects;
1284 
1285 	dump_stack();
1286 	return 0;
1287 }
1288 
1289 /*	pscsi_handle_SAM_STATUS_failures():
1290  *
1291  *
1292  */
1293 static inline void pscsi_process_SAM_status(
1294 	struct se_task *task,
1295 	struct pscsi_plugin_task *pt)
1296 {
1297 	task->task_scsi_status = status_byte(pt->pscsi_result);
1298 	if (task->task_scsi_status) {
1299 		task->task_scsi_status <<= 1;
1300 		pr_debug("PSCSI Status Byte exception at task: %p CDB:"
1301 			" 0x%02x Result: 0x%08x\n", task, pt->pscsi_cdb[0],
1302 			pt->pscsi_result);
1303 	}
1304 
1305 	switch (host_byte(pt->pscsi_result)) {
1306 	case DID_OK:
1307 		transport_complete_task(task, (!task->task_scsi_status));
1308 		break;
1309 	default:
1310 		pr_debug("PSCSI Host Byte exception at task: %p CDB:"
1311 			" 0x%02x Result: 0x%08x\n", task, pt->pscsi_cdb[0],
1312 			pt->pscsi_result);
1313 		task->task_scsi_status = SAM_STAT_CHECK_CONDITION;
1314 		task->task_error_status = PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
1315 		task->task_se_cmd->transport_error_status =
1316 					PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
1317 		transport_complete_task(task, 0);
1318 		break;
1319 	}
1320 }
1321 
1322 static void pscsi_req_done(struct request *req, int uptodate)
1323 {
1324 	struct se_task *task = req->end_io_data;
1325 	struct pscsi_plugin_task *pt = PSCSI_TASK(task);
1326 
1327 	pt->pscsi_result = req->errors;
1328 	pt->pscsi_resid = req->resid_len;
1329 
1330 	pscsi_process_SAM_status(task, pt);
1331 	/*
1332 	 * Release BIDI-READ if present
1333 	 */
1334 	if (req->next_rq != NULL)
1335 		__blk_put_request(req->q, req->next_rq);
1336 
1337 	__blk_put_request(req->q, req);
1338 	pt->pscsi_req = NULL;
1339 }
1340 
1341 static struct se_subsystem_api pscsi_template = {
1342 	.name			= "pscsi",
1343 	.owner			= THIS_MODULE,
1344 	.transport_type		= TRANSPORT_PLUGIN_PHBA_PDEV,
1345 	.cdb_none		= pscsi_CDB_none,
1346 	.map_control_SG		= pscsi_map_SG,
1347 	.map_data_SG		= pscsi_map_SG,
1348 	.attach_hba		= pscsi_attach_hba,
1349 	.detach_hba		= pscsi_detach_hba,
1350 	.pmode_enable_hba	= pscsi_pmode_enable_hba,
1351 	.allocate_virtdevice	= pscsi_allocate_virtdevice,
1352 	.create_virtdevice	= pscsi_create_virtdevice,
1353 	.free_device		= pscsi_free_device,
1354 	.transport_complete	= pscsi_transport_complete,
1355 	.alloc_task		= pscsi_alloc_task,
1356 	.do_task		= pscsi_do_task,
1357 	.free_task		= pscsi_free_task,
1358 	.check_configfs_dev_params = pscsi_check_configfs_dev_params,
1359 	.set_configfs_dev_params = pscsi_set_configfs_dev_params,
1360 	.show_configfs_dev_params = pscsi_show_configfs_dev_params,
1361 	.get_cdb		= pscsi_get_cdb,
1362 	.get_sense_buffer	= pscsi_get_sense_buffer,
1363 	.get_device_rev		= pscsi_get_device_rev,
1364 	.get_device_type	= pscsi_get_device_type,
1365 	.get_blocks		= pscsi_get_blocks,
1366 };
1367 
1368 static int __init pscsi_module_init(void)
1369 {
1370 	return transport_subsystem_register(&pscsi_template);
1371 }
1372 
1373 static void pscsi_module_exit(void)
1374 {
1375 	transport_subsystem_release(&pscsi_template);
1376 }
1377 
1378 MODULE_DESCRIPTION("TCM PSCSI subsystem plugin");
1379 MODULE_AUTHOR("nab@Linux-iSCSI.org");
1380 MODULE_LICENSE("GPL");
1381 
1382 module_init(pscsi_module_init);
1383 module_exit(pscsi_module_exit);
1384