1 /*
2  * Target driver for EMC CLARiiON AX/CX-series hardware.
3  * Based on code from Lars Marowsky-Bree <lmb@suse.de>
4  * and Ed Goggin <egoggin@emc.com>.
5  *
6  * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
7  * Copyright (C) 2006 Mike Christie
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2, or (at your option)
12  * any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; see the file COPYING.  If not, write to
21  * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
22  */
23 #include <linux/slab.h>
24 #include <linux/module.h>
25 #include <scsi/scsi.h>
26 #include <scsi/scsi_eh.h>
27 #include <scsi/scsi_dh.h>
28 #include <scsi/scsi_device.h>
29 
30 #define CLARIION_NAME			"emc"
31 
32 #define CLARIION_TRESPASS_PAGE		0x22
33 #define CLARIION_BUFFER_SIZE		0xFC
34 #define CLARIION_TIMEOUT		(60 * HZ)
35 #define CLARIION_RETRIES		3
36 #define CLARIION_UNBOUND_LU		-1
37 #define CLARIION_SP_A			0
38 #define CLARIION_SP_B			1
39 
40 /* Flags */
41 #define CLARIION_SHORT_TRESPASS		1
42 #define CLARIION_HONOR_RESERVATIONS	2
43 
44 /* LUN states */
45 #define CLARIION_LUN_UNINITIALIZED	-1
46 #define CLARIION_LUN_UNBOUND		0
47 #define CLARIION_LUN_BOUND		1
48 #define CLARIION_LUN_OWNED		2
49 
50 static unsigned char long_trespass[] = {
51 	0, 0, 0, 0, 0, 0, 0, 0,
52 	CLARIION_TRESPASS_PAGE,	/* Page code */
53 	0x09,			/* Page length - 2 */
54 	0x01,			/* Trespass code */
55 	0xff, 0xff,		/* Trespass target */
56 	0, 0, 0, 0, 0, 0	/* Reserved bytes / unknown */
57 };
58 
59 static unsigned char short_trespass[] = {
60 	0, 0, 0, 0,
61 	CLARIION_TRESPASS_PAGE,	/* Page code */
62 	0x02,			/* Page length - 2 */
63 	0x01,			/* Trespass code */
64 	0xff,			/* Trespass target */
65 };
66 
67 static const char * lun_state[] =
68 {
69     "not bound",
70     "bound",
71     "owned",
72 };
73 
74 struct clariion_dh_data {
75 	/*
76 	 * Flags:
77 	 *  CLARIION_SHORT_TRESPASS
78 	 * Use short trespass command (FC-series) or the long version
79 	 * (default for AX/CX CLARiiON arrays).
80 	 *
81 	 *  CLARIION_HONOR_RESERVATIONS
82 	 * Whether or not (default) to honor SCSI reservations when
83 	 * initiating a switch-over.
84 	 */
85 	unsigned flags;
86 	/*
87 	 * I/O buffer for both MODE_SELECT and INQUIRY commands.
88 	 */
89 	unsigned char buffer[CLARIION_BUFFER_SIZE];
90 	/*
91 	 * SCSI sense buffer for commands -- assumes serial issuance
92 	 * and completion sequence of all commands for same multipath.
93 	 */
94 	unsigned char sense[SCSI_SENSE_BUFFERSIZE];
95 	unsigned int senselen;
96 	/*
97 	 * LUN state
98 	 */
99 	int lun_state;
100 	/*
101 	 * SP Port number
102 	 */
103 	int port;
104 	/*
105 	 * which SP (A=0,B=1,UNBOUND=-1) is the default SP for this
106 	 * path's mapped LUN
107 	 */
108 	int default_sp;
109 	/*
110 	 * which SP (A=0,B=1,UNBOUND=-1) is the active SP for this
111 	 * path's mapped LUN
112 	 */
113 	int current_sp;
114 };
115 
116 static inline struct clariion_dh_data
117 			*get_clariion_data(struct scsi_device *sdev)
118 {
119 	struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
120 	BUG_ON(scsi_dh_data == NULL);
121 	return ((struct clariion_dh_data *) scsi_dh_data->buf);
122 }
123 
124 /*
125  * Parse MODE_SELECT cmd reply.
126  */
127 static int trespass_endio(struct scsi_device *sdev, char *sense)
128 {
129 	int err = SCSI_DH_IO;
130 	struct scsi_sense_hdr sshdr;
131 
132 	if (!scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)) {
133 		sdev_printk(KERN_ERR, sdev, "%s: Found valid sense data 0x%2x, "
134 			    "0x%2x, 0x%2x while sending CLARiiON trespass "
135 			    "command.\n", CLARIION_NAME, sshdr.sense_key,
136 			    sshdr.asc, sshdr.ascq);
137 
138 		if ((sshdr.sense_key == 0x05) && (sshdr.asc == 0x04) &&
139 		     (sshdr.ascq == 0x00)) {
140 			/*
141 			 * Array based copy in progress -- do not send
142 			 * mode_select or copy will be aborted mid-stream.
143 			 */
144 			sdev_printk(KERN_INFO, sdev, "%s: Array Based Copy in "
145 				    "progress while sending CLARiiON trespass "
146 				    "command.\n", CLARIION_NAME);
147 			err = SCSI_DH_DEV_TEMP_BUSY;
148 		} else if ((sshdr.sense_key == 0x02) && (sshdr.asc == 0x04) &&
149 			    (sshdr.ascq == 0x03)) {
150 			/*
151 			 * LUN Not Ready - Manual Intervention Required
152 			 * indicates in-progress ucode upgrade (NDU).
153 			 */
154 			sdev_printk(KERN_INFO, sdev, "%s: Detected in-progress "
155 				    "ucode upgrade NDU operation while sending "
156 				    "CLARiiON trespass command.\n", CLARIION_NAME);
157 			err = SCSI_DH_DEV_TEMP_BUSY;
158 		} else
159 			err = SCSI_DH_DEV_FAILED;
160 	} else {
161 		sdev_printk(KERN_INFO, sdev,
162 			    "%s: failed to send MODE SELECT, no sense available\n",
163 			    CLARIION_NAME);
164 	}
165 	return err;
166 }
167 
168 static int parse_sp_info_reply(struct scsi_device *sdev,
169 			       struct clariion_dh_data *csdev)
170 {
171 	int err = SCSI_DH_OK;
172 
173 	/* check for in-progress ucode upgrade (NDU) */
174 	if (csdev->buffer[48] != 0) {
175 		sdev_printk(KERN_NOTICE, sdev, "%s: Detected in-progress "
176 			    "ucode upgrade NDU operation while finding "
177 			    "current active SP.", CLARIION_NAME);
178 		err = SCSI_DH_DEV_TEMP_BUSY;
179 		goto out;
180 	}
181 	if (csdev->buffer[4] > 2) {
182 		/* Invalid buffer format */
183 		sdev_printk(KERN_NOTICE, sdev,
184 			    "%s: invalid VPD page 0xC0 format\n",
185 			    CLARIION_NAME);
186 		err = SCSI_DH_NOSYS;
187 		goto out;
188 	}
189 	switch (csdev->buffer[28] & 0x0f) {
190 	case 6:
191 		sdev_printk(KERN_NOTICE, sdev,
192 			    "%s: ALUA failover mode detected\n",
193 			    CLARIION_NAME);
194 		break;
195 	case 4:
196 		/* Linux failover */
197 		break;
198 	default:
199 		sdev_printk(KERN_WARNING, sdev,
200 			    "%s: Invalid failover mode %d\n",
201 			    CLARIION_NAME, csdev->buffer[28] & 0x0f);
202 		err = SCSI_DH_NOSYS;
203 		goto out;
204 	}
205 
206 	csdev->default_sp = csdev->buffer[5];
207 	csdev->lun_state = csdev->buffer[4];
208 	csdev->current_sp = csdev->buffer[8];
209 	csdev->port = csdev->buffer[7];
210 
211 out:
212 	return err;
213 }
214 
215 #define emc_default_str "FC (Legacy)"
216 
217 static char * parse_sp_model(struct scsi_device *sdev, unsigned char *buffer)
218 {
219 	unsigned char len = buffer[4] + 5;
220 	char *sp_model = NULL;
221 	unsigned char sp_len, serial_len;
222 
223 	if (len < 160) {
224 		sdev_printk(KERN_WARNING, sdev,
225 			    "%s: Invalid information section length %d\n",
226 			    CLARIION_NAME, len);
227 		/* Check for old FC arrays */
228 		if (!strncmp(buffer + 8, "DGC", 3)) {
229 			/* Old FC array, not supporting extended information */
230 			sp_model = emc_default_str;
231 		}
232 		goto out;
233 	}
234 
235 	/*
236 	 * Parse extended information for SP model number
237 	 */
238 	serial_len = buffer[160];
239 	if (serial_len == 0 || serial_len + 161 > len) {
240 		sdev_printk(KERN_WARNING, sdev,
241 			    "%s: Invalid array serial number length %d\n",
242 			    CLARIION_NAME, serial_len);
243 		goto out;
244 	}
245 	sp_len = buffer[99];
246 	if (sp_len == 0 || serial_len + sp_len + 161 > len) {
247 		sdev_printk(KERN_WARNING, sdev,
248 			    "%s: Invalid model number length %d\n",
249 			    CLARIION_NAME, sp_len);
250 		goto out;
251 	}
252 	sp_model = &buffer[serial_len + 161];
253 	/* Strip whitespace at the end */
254 	while (sp_len > 1 && sp_model[sp_len - 1] == ' ')
255 		sp_len--;
256 
257 	sp_model[sp_len] = '\0';
258 
259 out:
260 	return sp_model;
261 }
262 
263 /*
264  * Get block request for REQ_BLOCK_PC command issued to path.  Currently
265  * limited to MODE_SELECT (trespass) and INQUIRY (VPD page 0xC0) commands.
266  *
267  * Uses data and sense buffers in hardware handler context structure and
268  * assumes serial servicing of commands, both issuance and completion.
269  */
270 static struct request *get_req(struct scsi_device *sdev, int cmd,
271 				unsigned char *buffer)
272 {
273 	struct request *rq;
274 	int len = 0;
275 
276 	rq = blk_get_request(sdev->request_queue,
277 			(cmd != INQUIRY) ? WRITE : READ, GFP_NOIO);
278 	if (IS_ERR(rq)) {
279 		sdev_printk(KERN_INFO, sdev, "get_req: blk_get_request failed");
280 		return NULL;
281 	}
282 
283 	blk_rq_set_block_pc(rq);
284 	rq->cmd_len = COMMAND_SIZE(cmd);
285 	rq->cmd[0] = cmd;
286 
287 	switch (cmd) {
288 	case MODE_SELECT:
289 		len = sizeof(short_trespass);
290 		rq->cmd[1] = 0x10;
291 		rq->cmd[4] = len;
292 		break;
293 	case MODE_SELECT_10:
294 		len = sizeof(long_trespass);
295 		rq->cmd[1] = 0x10;
296 		rq->cmd[8] = len;
297 		break;
298 	case INQUIRY:
299 		len = CLARIION_BUFFER_SIZE;
300 		rq->cmd[4] = len;
301 		memset(buffer, 0, len);
302 		break;
303 	default:
304 		BUG_ON(1);
305 		break;
306 	}
307 
308 	rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
309 			 REQ_FAILFAST_DRIVER;
310 	rq->timeout = CLARIION_TIMEOUT;
311 	rq->retries = CLARIION_RETRIES;
312 
313 	if (blk_rq_map_kern(rq->q, rq, buffer, len, GFP_NOIO)) {
314 		blk_put_request(rq);
315 		return NULL;
316 	}
317 
318 	return rq;
319 }
320 
321 static int send_inquiry_cmd(struct scsi_device *sdev, int page,
322 			    struct clariion_dh_data *csdev)
323 {
324 	struct request *rq = get_req(sdev, INQUIRY, csdev->buffer);
325 	int err;
326 
327 	if (!rq)
328 		return SCSI_DH_RES_TEMP_UNAVAIL;
329 
330 	rq->sense = csdev->sense;
331 	memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
332 	rq->sense_len = csdev->senselen = 0;
333 
334 	rq->cmd[0] = INQUIRY;
335 	if (page != 0) {
336 		rq->cmd[1] = 1;
337 		rq->cmd[2] = page;
338 	}
339 	err = blk_execute_rq(sdev->request_queue, NULL, rq, 1);
340 	if (err == -EIO) {
341 		sdev_printk(KERN_INFO, sdev,
342 			    "%s: failed to send %s INQUIRY: %x\n",
343 			    CLARIION_NAME, page?"EVPD":"standard",
344 			    rq->errors);
345 		csdev->senselen = rq->sense_len;
346 		err = SCSI_DH_IO;
347 	}
348 
349 	blk_put_request(rq);
350 
351 	return err;
352 }
353 
354 static int send_trespass_cmd(struct scsi_device *sdev,
355 			    struct clariion_dh_data *csdev)
356 {
357 	struct request *rq;
358 	unsigned char *page22;
359 	int err, len, cmd;
360 
361 	if (csdev->flags & CLARIION_SHORT_TRESPASS) {
362 		page22 = short_trespass;
363 		if (!(csdev->flags & CLARIION_HONOR_RESERVATIONS))
364 			/* Set Honor Reservations bit */
365 			page22[6] |= 0x80;
366 		len = sizeof(short_trespass);
367 		cmd = MODE_SELECT;
368 	} else {
369 		page22 = long_trespass;
370 		if (!(csdev->flags & CLARIION_HONOR_RESERVATIONS))
371 			/* Set Honor Reservations bit */
372 			page22[10] |= 0x80;
373 		len = sizeof(long_trespass);
374 		cmd = MODE_SELECT_10;
375 	}
376 	BUG_ON((len > CLARIION_BUFFER_SIZE));
377 	memcpy(csdev->buffer, page22, len);
378 
379 	rq = get_req(sdev, cmd, csdev->buffer);
380 	if (!rq)
381 		return SCSI_DH_RES_TEMP_UNAVAIL;
382 
383 	rq->sense = csdev->sense;
384 	memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
385 	rq->sense_len = csdev->senselen = 0;
386 
387 	err = blk_execute_rq(sdev->request_queue, NULL, rq, 1);
388 	if (err == -EIO) {
389 		if (rq->sense_len) {
390 			err = trespass_endio(sdev, csdev->sense);
391 		} else {
392 			sdev_printk(KERN_INFO, sdev,
393 				    "%s: failed to send MODE SELECT: %x\n",
394 				    CLARIION_NAME, rq->errors);
395 		}
396 	}
397 
398 	blk_put_request(rq);
399 
400 	return err;
401 }
402 
403 static int clariion_check_sense(struct scsi_device *sdev,
404 				struct scsi_sense_hdr *sense_hdr)
405 {
406 	switch (sense_hdr->sense_key) {
407 	case NOT_READY:
408 		if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x03)
409 			/*
410 			 * LUN Not Ready - Manual Intervention Required
411 			 * indicates this is a passive path.
412 			 *
413 			 * FIXME: However, if this is seen and EVPD C0
414 			 * indicates that this is due to a NDU in
415 			 * progress, we should set FAIL_PATH too.
416 			 * This indicates we might have to do a SCSI
417 			 * inquiry in the end_io path. Ugh.
418 			 *
419 			 * Can return FAILED only when we want the error
420 			 * recovery process to kick in.
421 			 */
422 			return SUCCESS;
423 		break;
424 	case ILLEGAL_REQUEST:
425 		if (sense_hdr->asc == 0x25 && sense_hdr->ascq == 0x01)
426 			/*
427 			 * An array based copy is in progress. Do not
428 			 * fail the path, do not bypass to another PG,
429 			 * do not retry. Fail the IO immediately.
430 			 * (Actually this is the same conclusion as in
431 			 * the default handler, but lets make sure.)
432 			 *
433 			 * Can return FAILED only when we want the error
434 			 * recovery process to kick in.
435 			 */
436 			return SUCCESS;
437 		break;
438 	case UNIT_ATTENTION:
439 		if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
440 			/*
441 			 * Unit Attention Code. This is the first IO
442 			 * to the new path, so just retry.
443 			 */
444 			return ADD_TO_MLQUEUE;
445 		break;
446 	}
447 
448 	return SCSI_RETURN_NOT_HANDLED;
449 }
450 
451 static int clariion_prep_fn(struct scsi_device *sdev, struct request *req)
452 {
453 	struct clariion_dh_data *h = get_clariion_data(sdev);
454 	int ret = BLKPREP_OK;
455 
456 	if (h->lun_state != CLARIION_LUN_OWNED) {
457 		ret = BLKPREP_KILL;
458 		req->cmd_flags |= REQ_QUIET;
459 	}
460 	return ret;
461 
462 }
463 
464 static int clariion_std_inquiry(struct scsi_device *sdev,
465 				struct clariion_dh_data *csdev)
466 {
467 	int err;
468 	char *sp_model;
469 
470 	err = send_inquiry_cmd(sdev, 0, csdev);
471 	if (err != SCSI_DH_OK && csdev->senselen) {
472 		struct scsi_sense_hdr sshdr;
473 
474 		if (scsi_normalize_sense(csdev->sense, SCSI_SENSE_BUFFERSIZE,
475 					 &sshdr)) {
476 			sdev_printk(KERN_ERR, sdev, "%s: INQUIRY sense code "
477 				    "%02x/%02x/%02x\n", CLARIION_NAME,
478 				    sshdr.sense_key, sshdr.asc, sshdr.ascq);
479 		}
480 		err = SCSI_DH_IO;
481 		goto out;
482 	}
483 
484 	sp_model = parse_sp_model(sdev, csdev->buffer);
485 	if (!sp_model) {
486 		err = SCSI_DH_DEV_UNSUPP;
487 		goto out;
488 	}
489 
490 	/*
491 	 * FC Series arrays do not support long trespass
492 	 */
493 	if (!strlen(sp_model) || !strncmp(sp_model, "FC",2))
494 		csdev->flags |= CLARIION_SHORT_TRESPASS;
495 
496 	sdev_printk(KERN_INFO, sdev,
497 		    "%s: detected Clariion %s, flags %x\n",
498 		    CLARIION_NAME, sp_model, csdev->flags);
499 out:
500 	return err;
501 }
502 
503 static int clariion_send_inquiry(struct scsi_device *sdev,
504 				 struct clariion_dh_data *csdev)
505 {
506 	int err, retry = CLARIION_RETRIES;
507 
508 retry:
509 	err = send_inquiry_cmd(sdev, 0xC0, csdev);
510 	if (err != SCSI_DH_OK && csdev->senselen) {
511 		struct scsi_sense_hdr sshdr;
512 
513 		err = scsi_normalize_sense(csdev->sense, SCSI_SENSE_BUFFERSIZE,
514 					   &sshdr);
515 		if (!err)
516 			return SCSI_DH_IO;
517 
518 		err = clariion_check_sense(sdev, &sshdr);
519 		if (retry > 0 && err == ADD_TO_MLQUEUE) {
520 			retry--;
521 			goto retry;
522 		}
523 		sdev_printk(KERN_ERR, sdev, "%s: INQUIRY sense code "
524 			    "%02x/%02x/%02x\n", CLARIION_NAME,
525 			      sshdr.sense_key, sshdr.asc, sshdr.ascq);
526 		err = SCSI_DH_IO;
527 	} else {
528 		err = parse_sp_info_reply(sdev, csdev);
529 	}
530 	return err;
531 }
532 
533 static int clariion_activate(struct scsi_device *sdev,
534 				activate_complete fn, void *data)
535 {
536 	struct clariion_dh_data *csdev = get_clariion_data(sdev);
537 	int result;
538 
539 	result = clariion_send_inquiry(sdev, csdev);
540 	if (result != SCSI_DH_OK)
541 		goto done;
542 
543 	if (csdev->lun_state == CLARIION_LUN_OWNED)
544 		goto done;
545 
546 	result = send_trespass_cmd(sdev, csdev);
547 	if (result != SCSI_DH_OK)
548 		goto done;
549 	sdev_printk(KERN_INFO, sdev,"%s: %s trespass command sent\n",
550 		    CLARIION_NAME,
551 		    csdev->flags&CLARIION_SHORT_TRESPASS?"short":"long" );
552 
553 	/* Update status */
554 	result = clariion_send_inquiry(sdev, csdev);
555 	if (result != SCSI_DH_OK)
556 		goto done;
557 
558 done:
559 	sdev_printk(KERN_INFO, sdev,
560 		    "%s: at SP %c Port %d (%s, default SP %c)\n",
561 		    CLARIION_NAME, csdev->current_sp + 'A',
562 		    csdev->port, lun_state[csdev->lun_state],
563 		    csdev->default_sp + 'A');
564 
565 	if (fn)
566 		fn(data, result);
567 	return 0;
568 }
569 /*
570  * params - parameters in the following format
571  *      "no_of_params\0param1\0param2\0param3\0...\0"
572  *      for example, string for 2 parameters with value 10 and 21
573  *      is specified as "2\010\021\0".
574  */
575 static int clariion_set_params(struct scsi_device *sdev, const char *params)
576 {
577 	struct clariion_dh_data *csdev = get_clariion_data(sdev);
578 	unsigned int hr = 0, st = 0, argc;
579 	const char *p = params;
580 	int result = SCSI_DH_OK;
581 
582 	if ((sscanf(params, "%u", &argc) != 1) || (argc != 2))
583 		return -EINVAL;
584 
585 	while (*p++)
586 		;
587 	if ((sscanf(p, "%u", &st) != 1) || (st > 1))
588 		return -EINVAL;
589 
590 	while (*p++)
591 		;
592 	if ((sscanf(p, "%u", &hr) != 1) || (hr > 1))
593 		return -EINVAL;
594 
595 	if (st)
596 		csdev->flags |= CLARIION_SHORT_TRESPASS;
597 	else
598 		csdev->flags &= ~CLARIION_SHORT_TRESPASS;
599 
600 	if (hr)
601 		csdev->flags |= CLARIION_HONOR_RESERVATIONS;
602 	else
603 		csdev->flags &= ~CLARIION_HONOR_RESERVATIONS;
604 
605 	/*
606 	 * If this path is owned, we have to send a trespass command
607 	 * with the new parameters. If not, simply return. Next trespass
608 	 * command would use the parameters.
609 	 */
610 	if (csdev->lun_state != CLARIION_LUN_OWNED)
611 		goto done;
612 
613 	csdev->lun_state = CLARIION_LUN_UNINITIALIZED;
614 	result = send_trespass_cmd(sdev, csdev);
615 	if (result != SCSI_DH_OK)
616 		goto done;
617 
618 	/* Update status */
619 	result = clariion_send_inquiry(sdev, csdev);
620 
621 done:
622 	return result;
623 }
624 
625 static const struct scsi_dh_devlist clariion_dev_list[] = {
626 	{"DGC", "RAID"},
627 	{"DGC", "DISK"},
628 	{"DGC", "VRAID"},
629 	{NULL, NULL},
630 };
631 
632 static bool clariion_match(struct scsi_device *sdev)
633 {
634 	int i;
635 
636 	if (scsi_device_tpgs(sdev))
637 		return false;
638 
639 	for (i = 0; clariion_dev_list[i].vendor; i++) {
640 		if (!strncmp(sdev->vendor, clariion_dev_list[i].vendor,
641 			strlen(clariion_dev_list[i].vendor)) &&
642 		    !strncmp(sdev->model, clariion_dev_list[i].model,
643 			strlen(clariion_dev_list[i].model))) {
644 			return true;
645 		}
646 	}
647 	return false;
648 }
649 
650 static int clariion_bus_attach(struct scsi_device *sdev);
651 static void clariion_bus_detach(struct scsi_device *sdev);
652 
653 static struct scsi_device_handler clariion_dh = {
654 	.name		= CLARIION_NAME,
655 	.module		= THIS_MODULE,
656 	.devlist	= clariion_dev_list,
657 	.attach		= clariion_bus_attach,
658 	.detach		= clariion_bus_detach,
659 	.check_sense	= clariion_check_sense,
660 	.activate	= clariion_activate,
661 	.prep_fn	= clariion_prep_fn,
662 	.set_params	= clariion_set_params,
663 	.match		= clariion_match,
664 };
665 
666 static int clariion_bus_attach(struct scsi_device *sdev)
667 {
668 	struct scsi_dh_data *scsi_dh_data;
669 	struct clariion_dh_data *h;
670 	unsigned long flags;
671 	int err;
672 
673 	scsi_dh_data = kzalloc(sizeof(*scsi_dh_data)
674 			       + sizeof(*h) , GFP_KERNEL);
675 	if (!scsi_dh_data) {
676 		sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n",
677 			    CLARIION_NAME);
678 		return -ENOMEM;
679 	}
680 
681 	scsi_dh_data->scsi_dh = &clariion_dh;
682 	h = (struct clariion_dh_data *) scsi_dh_data->buf;
683 	h->lun_state = CLARIION_LUN_UNINITIALIZED;
684 	h->default_sp = CLARIION_UNBOUND_LU;
685 	h->current_sp = CLARIION_UNBOUND_LU;
686 
687 	err = clariion_std_inquiry(sdev, h);
688 	if (err != SCSI_DH_OK)
689 		goto failed;
690 
691 	err = clariion_send_inquiry(sdev, h);
692 	if (err != SCSI_DH_OK)
693 		goto failed;
694 
695 	if (!try_module_get(THIS_MODULE))
696 		goto failed;
697 
698 	spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
699 	sdev->scsi_dh_data = scsi_dh_data;
700 	spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
701 
702 	sdev_printk(KERN_INFO, sdev,
703 		    "%s: connected to SP %c Port %d (%s, default SP %c)\n",
704 		    CLARIION_NAME, h->current_sp + 'A',
705 		    h->port, lun_state[h->lun_state],
706 		    h->default_sp + 'A');
707 
708 	return 0;
709 
710 failed:
711 	kfree(scsi_dh_data);
712 	sdev_printk(KERN_ERR, sdev, "%s: not attached\n",
713 		    CLARIION_NAME);
714 	return -EINVAL;
715 }
716 
717 static void clariion_bus_detach(struct scsi_device *sdev)
718 {
719 	struct scsi_dh_data *scsi_dh_data;
720 	unsigned long flags;
721 
722 	spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
723 	scsi_dh_data = sdev->scsi_dh_data;
724 	sdev->scsi_dh_data = NULL;
725 	spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
726 
727 	sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n",
728 		    CLARIION_NAME);
729 
730 	kfree(scsi_dh_data);
731 	module_put(THIS_MODULE);
732 }
733 
734 static int __init clariion_init(void)
735 {
736 	int r;
737 
738 	r = scsi_register_device_handler(&clariion_dh);
739 	if (r != 0)
740 		printk(KERN_ERR "%s: Failed to register scsi device handler.",
741 			CLARIION_NAME);
742 	return r;
743 }
744 
745 static void __exit clariion_exit(void)
746 {
747 	scsi_unregister_device_handler(&clariion_dh);
748 }
749 
750 module_init(clariion_init);
751 module_exit(clariion_exit);
752 
753 MODULE_DESCRIPTION("EMC CX/AX/FC-family driver");
754 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, Chandra Seetharaman <sekharan@us.ibm.com>");
755 MODULE_LICENSE("GPL");
756