xref: /linux/drivers/scsi/ses.c (revision 83bce9c2baa51e439480a713119a73d3c8b61083)
1 /*
2  * SCSI Enclosure Services
3  *
4  * Copyright (C) 2008 James Bottomley <James.Bottomley@HansenPartnership.com>
5  *
6 **-----------------------------------------------------------------------------
7 **
8 **  This program is free software; you can redistribute it and/or
9 **  modify it under the terms of the GNU General Public License
10 **  version 2 as published by the Free Software Foundation.
11 **
12 **  This program is distributed in the hope that it will be useful,
13 **  but WITHOUT ANY WARRANTY; without even the implied warranty of
14 **  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 **  GNU General Public License for more details.
16 **
17 **  You should have received a copy of the GNU General Public License
18 **  along with this program; if not, write to the Free Software
19 **  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 **
21 **-----------------------------------------------------------------------------
22 */
23 
24 #include <linux/slab.h>
25 #include <linux/module.h>
26 #include <linux/kernel.h>
27 #include <linux/enclosure.h>
28 #include <asm/unaligned.h>
29 
30 #include <scsi/scsi.h>
31 #include <scsi/scsi_cmnd.h>
32 #include <scsi/scsi_dbg.h>
33 #include <scsi/scsi_device.h>
34 #include <scsi/scsi_driver.h>
35 #include <scsi/scsi_host.h>
36 
37 #include <scsi/scsi_transport_sas.h>
38 
39 struct ses_device {
40 	unsigned char *page1;
41 	unsigned char *page1_types;
42 	unsigned char *page2;
43 	unsigned char *page10;
44 	short page1_len;
45 	short page1_num_types;
46 	short page2_len;
47 	short page10_len;
48 };
49 
50 struct ses_component {
51 	u64 addr;
52 };
53 
54 static int ses_probe(struct device *dev)
55 {
56 	struct scsi_device *sdev = to_scsi_device(dev);
57 	int err = -ENODEV;
58 
59 	if (sdev->type != TYPE_ENCLOSURE)
60 		goto out;
61 
62 	err = 0;
63 	sdev_printk(KERN_NOTICE, sdev, "Attached Enclosure device\n");
64 
65  out:
66 	return err;
67 }
68 
69 #define SES_TIMEOUT (30 * HZ)
70 #define SES_RETRIES 3
71 
72 static void init_device_slot_control(unsigned char *dest_desc,
73 				     struct enclosure_component *ecomp,
74 				     unsigned char *status)
75 {
76 	memcpy(dest_desc, status, 4);
77 	dest_desc[0] = 0;
78 	/* only clear byte 1 for ENCLOSURE_COMPONENT_DEVICE */
79 	if (ecomp->type == ENCLOSURE_COMPONENT_DEVICE)
80 		dest_desc[1] = 0;
81 	dest_desc[2] &= 0xde;
82 	dest_desc[3] &= 0x3c;
83 }
84 
85 
86 static int ses_recv_diag(struct scsi_device *sdev, int page_code,
87 			 void *buf, int bufflen)
88 {
89 	int ret;
90 	unsigned char cmd[] = {
91 		RECEIVE_DIAGNOSTIC,
92 		1,		/* Set PCV bit */
93 		page_code,
94 		bufflen >> 8,
95 		bufflen & 0xff,
96 		0
97 	};
98 	unsigned char recv_page_code;
99 
100 	ret =  scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buf, bufflen,
101 				NULL, SES_TIMEOUT, SES_RETRIES, NULL);
102 	if (unlikely(!ret))
103 		return ret;
104 
105 	recv_page_code = ((unsigned char *)buf)[0];
106 
107 	if (likely(recv_page_code == page_code))
108 		return ret;
109 
110 	/* successful diagnostic but wrong page code.  This happens to some
111 	 * USB devices, just print a message and pretend there was an error */
112 
113 	sdev_printk(KERN_ERR, sdev,
114 		    "Wrong diagnostic page; asked for %d got %u\n",
115 		    page_code, recv_page_code);
116 
117 	return -EINVAL;
118 }
119 
120 static int ses_send_diag(struct scsi_device *sdev, int page_code,
121 			 void *buf, int bufflen)
122 {
123 	u32 result;
124 
125 	unsigned char cmd[] = {
126 		SEND_DIAGNOSTIC,
127 		0x10,		/* Set PF bit */
128 		0,
129 		bufflen >> 8,
130 		bufflen & 0xff,
131 		0
132 	};
133 
134 	result = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, buf, bufflen,
135 				  NULL, SES_TIMEOUT, SES_RETRIES, NULL);
136 	if (result)
137 		sdev_printk(KERN_ERR, sdev, "SEND DIAGNOSTIC result: %8x\n",
138 			    result);
139 	return result;
140 }
141 
142 static int ses_set_page2_descriptor(struct enclosure_device *edev,
143 				      struct enclosure_component *ecomp,
144 				      unsigned char *desc)
145 {
146 	int i, j, count = 0, descriptor = ecomp->number;
147 	struct scsi_device *sdev = to_scsi_device(edev->edev.parent);
148 	struct ses_device *ses_dev = edev->scratch;
149 	unsigned char *type_ptr = ses_dev->page1_types;
150 	unsigned char *desc_ptr = ses_dev->page2 + 8;
151 
152 	/* Clear everything */
153 	memset(desc_ptr, 0, ses_dev->page2_len - 8);
154 	for (i = 0; i < ses_dev->page1_num_types; i++, type_ptr += 4) {
155 		for (j = 0; j < type_ptr[1]; j++) {
156 			desc_ptr += 4;
157 			if (type_ptr[0] != ENCLOSURE_COMPONENT_DEVICE &&
158 			    type_ptr[0] != ENCLOSURE_COMPONENT_ARRAY_DEVICE)
159 				continue;
160 			if (count++ == descriptor) {
161 				memcpy(desc_ptr, desc, 4);
162 				/* set select */
163 				desc_ptr[0] |= 0x80;
164 				/* clear reserved, just in case */
165 				desc_ptr[0] &= 0xf0;
166 			}
167 		}
168 	}
169 
170 	return ses_send_diag(sdev, 2, ses_dev->page2, ses_dev->page2_len);
171 }
172 
173 static unsigned char *ses_get_page2_descriptor(struct enclosure_device *edev,
174 				      struct enclosure_component *ecomp)
175 {
176 	int i, j, count = 0, descriptor = ecomp->number;
177 	struct scsi_device *sdev = to_scsi_device(edev->edev.parent);
178 	struct ses_device *ses_dev = edev->scratch;
179 	unsigned char *type_ptr = ses_dev->page1_types;
180 	unsigned char *desc_ptr = ses_dev->page2 + 8;
181 
182 	ses_recv_diag(sdev, 2, ses_dev->page2, ses_dev->page2_len);
183 
184 	for (i = 0; i < ses_dev->page1_num_types; i++, type_ptr += 4) {
185 		for (j = 0; j < type_ptr[1]; j++) {
186 			desc_ptr += 4;
187 			if (type_ptr[0] != ENCLOSURE_COMPONENT_DEVICE &&
188 			    type_ptr[0] != ENCLOSURE_COMPONENT_ARRAY_DEVICE)
189 				continue;
190 			if (count++ == descriptor)
191 				return desc_ptr;
192 		}
193 	}
194 	return NULL;
195 }
196 
197 /* For device slot and array device slot elements, byte 3 bit 6
198  * is "fault sensed" while byte 3 bit 5 is "fault reqstd". As this
199  * code stands these bits are shifted 4 positions right so in
200  * sysfs they will appear as bits 2 and 1 respectively. Strange. */
201 static void ses_get_fault(struct enclosure_device *edev,
202 			  struct enclosure_component *ecomp)
203 {
204 	unsigned char *desc;
205 
206 	desc = ses_get_page2_descriptor(edev, ecomp);
207 	if (desc)
208 		ecomp->fault = (desc[3] & 0x60) >> 4;
209 }
210 
211 static int ses_set_fault(struct enclosure_device *edev,
212 			  struct enclosure_component *ecomp,
213 			 enum enclosure_component_setting val)
214 {
215 	unsigned char desc[4];
216 	unsigned char *desc_ptr;
217 
218 	desc_ptr = ses_get_page2_descriptor(edev, ecomp);
219 
220 	if (!desc_ptr)
221 		return -EIO;
222 
223 	init_device_slot_control(desc, ecomp, desc_ptr);
224 
225 	switch (val) {
226 	case ENCLOSURE_SETTING_DISABLED:
227 		desc[3] &= 0xdf;
228 		break;
229 	case ENCLOSURE_SETTING_ENABLED:
230 		desc[3] |= 0x20;
231 		break;
232 	default:
233 		/* SES doesn't do the SGPIO blink settings */
234 		return -EINVAL;
235 	}
236 
237 	return ses_set_page2_descriptor(edev, ecomp, desc);
238 }
239 
240 static void ses_get_status(struct enclosure_device *edev,
241 			   struct enclosure_component *ecomp)
242 {
243 	unsigned char *desc;
244 
245 	desc = ses_get_page2_descriptor(edev, ecomp);
246 	if (desc)
247 		ecomp->status = (desc[0] & 0x0f);
248 }
249 
250 static void ses_get_locate(struct enclosure_device *edev,
251 			   struct enclosure_component *ecomp)
252 {
253 	unsigned char *desc;
254 
255 	desc = ses_get_page2_descriptor(edev, ecomp);
256 	if (desc)
257 		ecomp->locate = (desc[2] & 0x02) ? 1 : 0;
258 }
259 
260 static int ses_set_locate(struct enclosure_device *edev,
261 			  struct enclosure_component *ecomp,
262 			  enum enclosure_component_setting val)
263 {
264 	unsigned char desc[4];
265 	unsigned char *desc_ptr;
266 
267 	desc_ptr = ses_get_page2_descriptor(edev, ecomp);
268 
269 	if (!desc_ptr)
270 		return -EIO;
271 
272 	init_device_slot_control(desc, ecomp, desc_ptr);
273 
274 	switch (val) {
275 	case ENCLOSURE_SETTING_DISABLED:
276 		desc[2] &= 0xfd;
277 		break;
278 	case ENCLOSURE_SETTING_ENABLED:
279 		desc[2] |= 0x02;
280 		break;
281 	default:
282 		/* SES doesn't do the SGPIO blink settings */
283 		return -EINVAL;
284 	}
285 	return ses_set_page2_descriptor(edev, ecomp, desc);
286 }
287 
288 static int ses_set_active(struct enclosure_device *edev,
289 			  struct enclosure_component *ecomp,
290 			  enum enclosure_component_setting val)
291 {
292 	unsigned char desc[4];
293 	unsigned char *desc_ptr;
294 
295 	desc_ptr = ses_get_page2_descriptor(edev, ecomp);
296 
297 	if (!desc_ptr)
298 		return -EIO;
299 
300 	init_device_slot_control(desc, ecomp, desc_ptr);
301 
302 	switch (val) {
303 	case ENCLOSURE_SETTING_DISABLED:
304 		desc[2] &= 0x7f;
305 		ecomp->active = 0;
306 		break;
307 	case ENCLOSURE_SETTING_ENABLED:
308 		desc[2] |= 0x80;
309 		ecomp->active = 1;
310 		break;
311 	default:
312 		/* SES doesn't do the SGPIO blink settings */
313 		return -EINVAL;
314 	}
315 	return ses_set_page2_descriptor(edev, ecomp, desc);
316 }
317 
318 static int ses_show_id(struct enclosure_device *edev, char *buf)
319 {
320 	struct ses_device *ses_dev = edev->scratch;
321 	unsigned long long id = get_unaligned_be64(ses_dev->page1+8+4);
322 
323 	return sprintf(buf, "%#llx\n", id);
324 }
325 
326 static void ses_get_power_status(struct enclosure_device *edev,
327 				 struct enclosure_component *ecomp)
328 {
329 	unsigned char *desc;
330 
331 	desc = ses_get_page2_descriptor(edev, ecomp);
332 	if (desc)
333 		ecomp->power_status = (desc[3] & 0x10) ? 0 : 1;
334 }
335 
336 static int ses_set_power_status(struct enclosure_device *edev,
337 				struct enclosure_component *ecomp,
338 				int val)
339 {
340 	unsigned char desc[4];
341 	unsigned char *desc_ptr;
342 
343 	desc_ptr = ses_get_page2_descriptor(edev, ecomp);
344 
345 	if (!desc_ptr)
346 		return -EIO;
347 
348 	init_device_slot_control(desc, ecomp, desc_ptr);
349 
350 	switch (val) {
351 	/* power = 1 is device_off = 0 and vice versa */
352 	case 0:
353 		desc[3] |= 0x10;
354 		break;
355 	case 1:
356 		desc[3] &= 0xef;
357 		break;
358 	default:
359 		return -EINVAL;
360 	}
361 	ecomp->power_status = val;
362 	return ses_set_page2_descriptor(edev, ecomp, desc);
363 }
364 
365 static struct enclosure_component_callbacks ses_enclosure_callbacks = {
366 	.get_fault		= ses_get_fault,
367 	.set_fault		= ses_set_fault,
368 	.get_status		= ses_get_status,
369 	.get_locate		= ses_get_locate,
370 	.set_locate		= ses_set_locate,
371 	.get_power_status	= ses_get_power_status,
372 	.set_power_status	= ses_set_power_status,
373 	.set_active		= ses_set_active,
374 	.show_id		= ses_show_id,
375 };
376 
377 struct ses_host_edev {
378 	struct Scsi_Host *shost;
379 	struct enclosure_device *edev;
380 };
381 
382 #if 0
383 int ses_match_host(struct enclosure_device *edev, void *data)
384 {
385 	struct ses_host_edev *sed = data;
386 	struct scsi_device *sdev;
387 
388 	if (!scsi_is_sdev_device(edev->edev.parent))
389 		return 0;
390 
391 	sdev = to_scsi_device(edev->edev.parent);
392 
393 	if (sdev->host != sed->shost)
394 		return 0;
395 
396 	sed->edev = edev;
397 	return 1;
398 }
399 #endif  /*  0  */
400 
401 static void ses_process_descriptor(struct enclosure_component *ecomp,
402 				   unsigned char *desc)
403 {
404 	int eip = desc[0] & 0x10;
405 	int invalid = desc[0] & 0x80;
406 	enum scsi_protocol proto = desc[0] & 0x0f;
407 	u64 addr = 0;
408 	int slot = -1;
409 	struct ses_component *scomp = ecomp->scratch;
410 	unsigned char *d;
411 
412 	if (invalid)
413 		return;
414 
415 	switch (proto) {
416 	case SCSI_PROTOCOL_FCP:
417 		if (eip) {
418 			d = desc + 4;
419 			slot = d[3];
420 		}
421 		break;
422 	case SCSI_PROTOCOL_SAS:
423 		if (eip) {
424 			d = desc + 4;
425 			slot = d[3];
426 			d = desc + 8;
427 		} else
428 			d = desc + 4;
429 		/* only take the phy0 addr */
430 		addr = (u64)d[12] << 56 |
431 			(u64)d[13] << 48 |
432 			(u64)d[14] << 40 |
433 			(u64)d[15] << 32 |
434 			(u64)d[16] << 24 |
435 			(u64)d[17] << 16 |
436 			(u64)d[18] << 8 |
437 			(u64)d[19];
438 		break;
439 	default:
440 		/* FIXME: Need to add more protocols than just SAS */
441 		break;
442 	}
443 	ecomp->slot = slot;
444 	scomp->addr = addr;
445 }
446 
447 struct efd {
448 	u64 addr;
449 	struct device *dev;
450 };
451 
452 static int ses_enclosure_find_by_addr(struct enclosure_device *edev,
453 				      void *data)
454 {
455 	struct efd *efd = data;
456 	int i;
457 	struct ses_component *scomp;
458 
459 	if (!edev->component[0].scratch)
460 		return 0;
461 
462 	for (i = 0; i < edev->components; i++) {
463 		scomp = edev->component[i].scratch;
464 		if (scomp->addr != efd->addr)
465 			continue;
466 
467 		if (enclosure_add_device(edev, i, efd->dev) == 0)
468 			kobject_uevent(&efd->dev->kobj, KOBJ_CHANGE);
469 		return 1;
470 	}
471 	return 0;
472 }
473 
474 #define INIT_ALLOC_SIZE 32
475 
476 static void ses_enclosure_data_process(struct enclosure_device *edev,
477 				       struct scsi_device *sdev,
478 				       int create)
479 {
480 	u32 result;
481 	unsigned char *buf = NULL, *type_ptr, *desc_ptr, *addl_desc_ptr = NULL;
482 	int i, j, page7_len, len, components;
483 	struct ses_device *ses_dev = edev->scratch;
484 	int types = ses_dev->page1_num_types;
485 	unsigned char *hdr_buf = kzalloc(INIT_ALLOC_SIZE, GFP_KERNEL);
486 
487 	if (!hdr_buf)
488 		goto simple_populate;
489 
490 	/* re-read page 10 */
491 	if (ses_dev->page10)
492 		ses_recv_diag(sdev, 10, ses_dev->page10, ses_dev->page10_len);
493 	/* Page 7 for the descriptors is optional */
494 	result = ses_recv_diag(sdev, 7, hdr_buf, INIT_ALLOC_SIZE);
495 	if (result)
496 		goto simple_populate;
497 
498 	page7_len = len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
499 	/* add 1 for trailing '\0' we'll use */
500 	buf = kzalloc(len + 1, GFP_KERNEL);
501 	if (!buf)
502 		goto simple_populate;
503 	result = ses_recv_diag(sdev, 7, buf, len);
504 	if (result) {
505  simple_populate:
506 		kfree(buf);
507 		buf = NULL;
508 		desc_ptr = NULL;
509 		len = 0;
510 		page7_len = 0;
511 	} else {
512 		desc_ptr = buf + 8;
513 		len = (desc_ptr[2] << 8) + desc_ptr[3];
514 		/* skip past overall descriptor */
515 		desc_ptr += len + 4;
516 	}
517 	if (ses_dev->page10)
518 		addl_desc_ptr = ses_dev->page10 + 8;
519 	type_ptr = ses_dev->page1_types;
520 	components = 0;
521 	for (i = 0; i < types; i++, type_ptr += 4) {
522 		for (j = 0; j < type_ptr[1]; j++) {
523 			char *name = NULL;
524 			struct enclosure_component *ecomp;
525 
526 			if (desc_ptr) {
527 				if (desc_ptr >= buf + page7_len) {
528 					desc_ptr = NULL;
529 				} else {
530 					len = (desc_ptr[2] << 8) + desc_ptr[3];
531 					desc_ptr += 4;
532 					/* Add trailing zero - pushes into
533 					 * reserved space */
534 					desc_ptr[len] = '\0';
535 					name = desc_ptr;
536 				}
537 			}
538 			if (type_ptr[0] == ENCLOSURE_COMPONENT_DEVICE ||
539 			    type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE) {
540 
541 				if (create)
542 					ecomp =	enclosure_component_alloc(
543 						edev,
544 						components++,
545 						type_ptr[0],
546 						name);
547 				else
548 					ecomp = &edev->component[components++];
549 
550 				if (!IS_ERR(ecomp)) {
551 					ses_get_power_status(edev, ecomp);
552 					if (addl_desc_ptr)
553 						ses_process_descriptor(
554 							ecomp,
555 							addl_desc_ptr);
556 					if (create)
557 						enclosure_component_register(
558 							ecomp);
559 				}
560 			}
561 			if (desc_ptr)
562 				desc_ptr += len;
563 
564 			if (addl_desc_ptr &&
565 			    /* only find additional descriptions for specific devices */
566 			    (type_ptr[0] == ENCLOSURE_COMPONENT_DEVICE ||
567 			     type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE ||
568 			     type_ptr[0] == ENCLOSURE_COMPONENT_SAS_EXPANDER ||
569 			     /* these elements are optional */
570 			     type_ptr[0] == ENCLOSURE_COMPONENT_SCSI_TARGET_PORT ||
571 			     type_ptr[0] == ENCLOSURE_COMPONENT_SCSI_INITIATOR_PORT ||
572 			     type_ptr[0] == ENCLOSURE_COMPONENT_CONTROLLER_ELECTRONICS))
573 				addl_desc_ptr += addl_desc_ptr[1] + 2;
574 
575 		}
576 	}
577 	kfree(buf);
578 	kfree(hdr_buf);
579 }
580 
581 static void ses_match_to_enclosure(struct enclosure_device *edev,
582 				   struct scsi_device *sdev)
583 {
584 	struct efd efd = {
585 		.addr = 0,
586 	};
587 
588 	ses_enclosure_data_process(edev, to_scsi_device(edev->edev.parent), 0);
589 
590 	if (scsi_is_sas_rphy(sdev->sdev_target->dev.parent))
591 		efd.addr = sas_get_address(sdev);
592 
593 	if (efd.addr) {
594 		efd.dev = &sdev->sdev_gendev;
595 
596 		enclosure_for_each_device(ses_enclosure_find_by_addr, &efd);
597 	}
598 }
599 
600 static int ses_intf_add(struct device *cdev,
601 			struct class_interface *intf)
602 {
603 	struct scsi_device *sdev = to_scsi_device(cdev->parent);
604 	struct scsi_device *tmp_sdev;
605 	unsigned char *buf = NULL, *hdr_buf, *type_ptr;
606 	struct ses_device *ses_dev;
607 	u32 result;
608 	int i, types, len, components = 0;
609 	int err = -ENOMEM;
610 	int num_enclosures;
611 	struct enclosure_device *edev;
612 	struct ses_component *scomp = NULL;
613 
614 	if (!scsi_device_enclosure(sdev)) {
615 		/* not an enclosure, but might be in one */
616 		struct enclosure_device *prev = NULL;
617 
618 		while ((edev = enclosure_find(&sdev->host->shost_gendev, prev)) != NULL) {
619 			ses_match_to_enclosure(edev, sdev);
620 			prev = edev;
621 		}
622 		return -ENODEV;
623 	}
624 
625 	/* TYPE_ENCLOSURE prints a message in probe */
626 	if (sdev->type != TYPE_ENCLOSURE)
627 		sdev_printk(KERN_NOTICE, sdev, "Embedded Enclosure Device\n");
628 
629 	ses_dev = kzalloc(sizeof(*ses_dev), GFP_KERNEL);
630 	hdr_buf = kzalloc(INIT_ALLOC_SIZE, GFP_KERNEL);
631 	if (!hdr_buf || !ses_dev)
632 		goto err_init_free;
633 
634 	result = ses_recv_diag(sdev, 1, hdr_buf, INIT_ALLOC_SIZE);
635 	if (result)
636 		goto recv_failed;
637 
638 	len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
639 	buf = kzalloc(len, GFP_KERNEL);
640 	if (!buf)
641 		goto err_free;
642 
643 	result = ses_recv_diag(sdev, 1, buf, len);
644 	if (result)
645 		goto recv_failed;
646 
647 	types = 0;
648 
649 	/* we always have one main enclosure and the rest are referred
650 	 * to as secondary subenclosures */
651 	num_enclosures = buf[1] + 1;
652 
653 	/* begin at the enclosure descriptor */
654 	type_ptr = buf + 8;
655 	/* skip all the enclosure descriptors */
656 	for (i = 0; i < num_enclosures && type_ptr < buf + len; i++) {
657 		types += type_ptr[2];
658 		type_ptr += type_ptr[3] + 4;
659 	}
660 
661 	ses_dev->page1_types = type_ptr;
662 	ses_dev->page1_num_types = types;
663 
664 	for (i = 0; i < types && type_ptr < buf + len; i++, type_ptr += 4) {
665 		if (type_ptr[0] == ENCLOSURE_COMPONENT_DEVICE ||
666 		    type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE)
667 			components += type_ptr[1];
668 	}
669 	ses_dev->page1 = buf;
670 	ses_dev->page1_len = len;
671 	buf = NULL;
672 
673 	result = ses_recv_diag(sdev, 2, hdr_buf, INIT_ALLOC_SIZE);
674 	if (result)
675 		goto recv_failed;
676 
677 	len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
678 	buf = kzalloc(len, GFP_KERNEL);
679 	if (!buf)
680 		goto err_free;
681 
682 	/* make sure getting page 2 actually works */
683 	result = ses_recv_diag(sdev, 2, buf, len);
684 	if (result)
685 		goto recv_failed;
686 	ses_dev->page2 = buf;
687 	ses_dev->page2_len = len;
688 	buf = NULL;
689 
690 	/* The additional information page --- allows us
691 	 * to match up the devices */
692 	result = ses_recv_diag(sdev, 10, hdr_buf, INIT_ALLOC_SIZE);
693 	if (!result) {
694 
695 		len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
696 		buf = kzalloc(len, GFP_KERNEL);
697 		if (!buf)
698 			goto err_free;
699 
700 		result = ses_recv_diag(sdev, 10, buf, len);
701 		if (result)
702 			goto recv_failed;
703 		ses_dev->page10 = buf;
704 		ses_dev->page10_len = len;
705 		buf = NULL;
706 	}
707 	scomp = kzalloc(sizeof(struct ses_component) * components, GFP_KERNEL);
708 	if (!scomp)
709 		goto err_free;
710 
711 	edev = enclosure_register(cdev->parent, dev_name(&sdev->sdev_gendev),
712 				  components, &ses_enclosure_callbacks);
713 	if (IS_ERR(edev)) {
714 		err = PTR_ERR(edev);
715 		goto err_free;
716 	}
717 
718 	kfree(hdr_buf);
719 
720 	edev->scratch = ses_dev;
721 	for (i = 0; i < components; i++)
722 		edev->component[i].scratch = scomp + i;
723 
724 	ses_enclosure_data_process(edev, sdev, 1);
725 
726 	/* see if there are any devices matching before
727 	 * we found the enclosure */
728 	shost_for_each_device(tmp_sdev, sdev->host) {
729 		if (tmp_sdev->lun != 0 || scsi_device_enclosure(tmp_sdev))
730 			continue;
731 		ses_match_to_enclosure(edev, tmp_sdev);
732 	}
733 
734 	return 0;
735 
736  recv_failed:
737 	sdev_printk(KERN_ERR, sdev, "Failed to get diagnostic page 0x%x\n",
738 		    result);
739 	err = -ENODEV;
740  err_free:
741 	kfree(buf);
742 	kfree(scomp);
743 	kfree(ses_dev->page10);
744 	kfree(ses_dev->page2);
745 	kfree(ses_dev->page1);
746  err_init_free:
747 	kfree(ses_dev);
748 	kfree(hdr_buf);
749 	sdev_printk(KERN_ERR, sdev, "Failed to bind enclosure %d\n", err);
750 	return err;
751 }
752 
753 static int ses_remove(struct device *dev)
754 {
755 	return 0;
756 }
757 
758 static void ses_intf_remove_component(struct scsi_device *sdev)
759 {
760 	struct enclosure_device *edev, *prev = NULL;
761 
762 	while ((edev = enclosure_find(&sdev->host->shost_gendev, prev)) != NULL) {
763 		prev = edev;
764 		if (!enclosure_remove_device(edev, &sdev->sdev_gendev))
765 			break;
766 	}
767 	if (edev)
768 		put_device(&edev->edev);
769 }
770 
771 static void ses_intf_remove_enclosure(struct scsi_device *sdev)
772 {
773 	struct enclosure_device *edev;
774 	struct ses_device *ses_dev;
775 
776 	/*  exact match to this enclosure */
777 	edev = enclosure_find(&sdev->sdev_gendev, NULL);
778 	if (!edev)
779 		return;
780 
781 	enclosure_unregister(edev);
782 
783 	ses_dev = edev->scratch;
784 	edev->scratch = NULL;
785 
786 	kfree(ses_dev->page10);
787 	kfree(ses_dev->page1);
788 	kfree(ses_dev->page2);
789 	kfree(ses_dev);
790 
791 	kfree(edev->component[0].scratch);
792 
793 	put_device(&edev->edev);
794 }
795 
796 static void ses_intf_remove(struct device *cdev,
797 			    struct class_interface *intf)
798 {
799 	struct scsi_device *sdev = to_scsi_device(cdev->parent);
800 
801 	if (!scsi_device_enclosure(sdev))
802 		ses_intf_remove_component(sdev);
803 	else
804 		ses_intf_remove_enclosure(sdev);
805 }
806 
807 static struct class_interface ses_interface = {
808 	.add_dev	= ses_intf_add,
809 	.remove_dev	= ses_intf_remove,
810 };
811 
812 static struct scsi_driver ses_template = {
813 	.gendrv = {
814 		.name		= "ses",
815 		.owner		= THIS_MODULE,
816 		.probe		= ses_probe,
817 		.remove		= ses_remove,
818 	},
819 };
820 
821 static int __init ses_init(void)
822 {
823 	int err;
824 
825 	err = scsi_register_interface(&ses_interface);
826 	if (err)
827 		return err;
828 
829 	err = scsi_register_driver(&ses_template.gendrv);
830 	if (err)
831 		goto out_unreg;
832 
833 	return 0;
834 
835  out_unreg:
836 	scsi_unregister_interface(&ses_interface);
837 	return err;
838 }
839 
840 static void __exit ses_exit(void)
841 {
842 	scsi_unregister_driver(&ses_template.gendrv);
843 	scsi_unregister_interface(&ses_interface);
844 }
845 
846 module_init(ses_init);
847 module_exit(ses_exit);
848 
849 MODULE_ALIAS_SCSI_DEVICE(TYPE_ENCLOSURE);
850 
851 MODULE_AUTHOR("James Bottomley");
852 MODULE_DESCRIPTION("SCSI Enclosure Services (ses) driver");
853 MODULE_LICENSE("GPL v2");
854