xref: /linux/drivers/scsi/ses.c (revision ea8a163e02d6925773129e2dd86e419e491b791d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * SCSI Enclosure Services
4  *
5  * Copyright (C) 2008 James Bottomley <James.Bottomley@HansenPartnership.com>
6  */
7 
8 #include <linux/slab.h>
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/enclosure.h>
12 #include <asm/unaligned.h>
13 
14 #include <scsi/scsi.h>
15 #include <scsi/scsi_cmnd.h>
16 #include <scsi/scsi_dbg.h>
17 #include <scsi/scsi_device.h>
18 #include <scsi/scsi_driver.h>
19 #include <scsi/scsi_host.h>
20 
21 #include <scsi/scsi_transport_sas.h>
22 
23 struct ses_device {
24 	unsigned char *page1;
25 	unsigned char *page1_types;
26 	unsigned char *page2;
27 	unsigned char *page10;
28 	short page1_len;
29 	short page1_num_types;
30 	short page2_len;
31 	short page10_len;
32 };
33 
34 struct ses_component {
35 	u64 addr;
36 };
37 
38 static bool ses_page2_supported(struct enclosure_device *edev)
39 {
40 	struct ses_device *ses_dev = edev->scratch;
41 
42 	return (ses_dev->page2 != NULL);
43 }
44 
45 static int ses_probe(struct device *dev)
46 {
47 	struct scsi_device *sdev = to_scsi_device(dev);
48 	int err = -ENODEV;
49 
50 	if (sdev->type != TYPE_ENCLOSURE)
51 		goto out;
52 
53 	err = 0;
54 	sdev_printk(KERN_NOTICE, sdev, "Attached Enclosure device\n");
55 
56  out:
57 	return err;
58 }
59 
60 #define SES_TIMEOUT (30 * HZ)
61 #define SES_RETRIES 3
62 
63 static void init_device_slot_control(unsigned char *dest_desc,
64 				     struct enclosure_component *ecomp,
65 				     unsigned char *status)
66 {
67 	memcpy(dest_desc, status, 4);
68 	dest_desc[0] = 0;
69 	/* only clear byte 1 for ENCLOSURE_COMPONENT_DEVICE */
70 	if (ecomp->type == ENCLOSURE_COMPONENT_DEVICE)
71 		dest_desc[1] = 0;
72 	dest_desc[2] &= 0xde;
73 	dest_desc[3] &= 0x3c;
74 }
75 
76 
77 static int ses_recv_diag(struct scsi_device *sdev, int page_code,
78 			 void *buf, int bufflen)
79 {
80 	int ret;
81 	unsigned char cmd[] = {
82 		RECEIVE_DIAGNOSTIC,
83 		1,		/* Set PCV bit */
84 		page_code,
85 		bufflen >> 8,
86 		bufflen & 0xff,
87 		0
88 	};
89 	unsigned char recv_page_code;
90 	unsigned int retries = SES_RETRIES;
91 	struct scsi_sense_hdr sshdr;
92 
93 	do {
94 		ret = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buf, bufflen,
95 				       &sshdr, SES_TIMEOUT, 1, NULL);
96 	} while (ret > 0 && --retries && scsi_sense_valid(&sshdr) &&
97 		 (sshdr.sense_key == NOT_READY ||
98 		  (sshdr.sense_key == UNIT_ATTENTION && sshdr.asc == 0x29)));
99 
100 	if (unlikely(ret))
101 		return ret;
102 
103 	recv_page_code = ((unsigned char *)buf)[0];
104 
105 	if (likely(recv_page_code == page_code))
106 		return ret;
107 
108 	/* successful diagnostic but wrong page code.  This happens to some
109 	 * USB devices, just print a message and pretend there was an error */
110 
111 	sdev_printk(KERN_ERR, sdev,
112 		    "Wrong diagnostic page; asked for %d got %u\n",
113 		    page_code, recv_page_code);
114 
115 	return -EINVAL;
116 }
117 
118 static int ses_send_diag(struct scsi_device *sdev, int page_code,
119 			 void *buf, int bufflen)
120 {
121 	int result;
122 
123 	unsigned char cmd[] = {
124 		SEND_DIAGNOSTIC,
125 		0x10,		/* Set PF bit */
126 		0,
127 		bufflen >> 8,
128 		bufflen & 0xff,
129 		0
130 	};
131 	struct scsi_sense_hdr sshdr;
132 	unsigned int retries = SES_RETRIES;
133 
134 	do {
135 		result = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, buf, bufflen,
136 					  &sshdr, SES_TIMEOUT, 1, NULL);
137 	} while (result > 0 && --retries && scsi_sense_valid(&sshdr) &&
138 		 (sshdr.sense_key == NOT_READY ||
139 		  (sshdr.sense_key == UNIT_ATTENTION && sshdr.asc == 0x29)));
140 
141 	if (result)
142 		sdev_printk(KERN_ERR, sdev, "SEND DIAGNOSTIC result: %8x\n",
143 			    result);
144 	return result;
145 }
146 
147 static int ses_set_page2_descriptor(struct enclosure_device *edev,
148 				      struct enclosure_component *ecomp,
149 				      unsigned char *desc)
150 {
151 	int i, j, count = 0, descriptor = ecomp->number;
152 	struct scsi_device *sdev = to_scsi_device(edev->edev.parent);
153 	struct ses_device *ses_dev = edev->scratch;
154 	unsigned char *type_ptr = ses_dev->page1_types;
155 	unsigned char *desc_ptr = ses_dev->page2 + 8;
156 
157 	/* Clear everything */
158 	memset(desc_ptr, 0, ses_dev->page2_len - 8);
159 	for (i = 0; i < ses_dev->page1_num_types; i++, type_ptr += 4) {
160 		for (j = 0; j < type_ptr[1]; j++) {
161 			desc_ptr += 4;
162 			if (type_ptr[0] != ENCLOSURE_COMPONENT_DEVICE &&
163 			    type_ptr[0] != ENCLOSURE_COMPONENT_ARRAY_DEVICE)
164 				continue;
165 			if (count++ == descriptor) {
166 				memcpy(desc_ptr, desc, 4);
167 				/* set select */
168 				desc_ptr[0] |= 0x80;
169 				/* clear reserved, just in case */
170 				desc_ptr[0] &= 0xf0;
171 			}
172 		}
173 	}
174 
175 	return ses_send_diag(sdev, 2, ses_dev->page2, ses_dev->page2_len);
176 }
177 
178 static unsigned char *ses_get_page2_descriptor(struct enclosure_device *edev,
179 				      struct enclosure_component *ecomp)
180 {
181 	int i, j, count = 0, descriptor = ecomp->number;
182 	struct scsi_device *sdev = to_scsi_device(edev->edev.parent);
183 	struct ses_device *ses_dev = edev->scratch;
184 	unsigned char *type_ptr = ses_dev->page1_types;
185 	unsigned char *desc_ptr = ses_dev->page2 + 8;
186 
187 	if (ses_recv_diag(sdev, 2, ses_dev->page2, ses_dev->page2_len) < 0)
188 		return NULL;
189 
190 	for (i = 0; i < ses_dev->page1_num_types; i++, type_ptr += 4) {
191 		for (j = 0; j < type_ptr[1]; j++) {
192 			desc_ptr += 4;
193 			if (type_ptr[0] != ENCLOSURE_COMPONENT_DEVICE &&
194 			    type_ptr[0] != ENCLOSURE_COMPONENT_ARRAY_DEVICE)
195 				continue;
196 			if (count++ == descriptor)
197 				return desc_ptr;
198 		}
199 	}
200 	return NULL;
201 }
202 
203 /* For device slot and array device slot elements, byte 3 bit 6
204  * is "fault sensed" while byte 3 bit 5 is "fault reqstd". As this
205  * code stands these bits are shifted 4 positions right so in
206  * sysfs they will appear as bits 2 and 1 respectively. Strange. */
207 static void ses_get_fault(struct enclosure_device *edev,
208 			  struct enclosure_component *ecomp)
209 {
210 	unsigned char *desc;
211 
212 	if (!ses_page2_supported(edev)) {
213 		ecomp->fault = 0;
214 		return;
215 	}
216 	desc = ses_get_page2_descriptor(edev, ecomp);
217 	if (desc)
218 		ecomp->fault = (desc[3] & 0x60) >> 4;
219 }
220 
221 static int ses_set_fault(struct enclosure_device *edev,
222 			  struct enclosure_component *ecomp,
223 			 enum enclosure_component_setting val)
224 {
225 	unsigned char desc[4];
226 	unsigned char *desc_ptr;
227 
228 	if (!ses_page2_supported(edev))
229 		return -EINVAL;
230 
231 	desc_ptr = ses_get_page2_descriptor(edev, ecomp);
232 
233 	if (!desc_ptr)
234 		return -EIO;
235 
236 	init_device_slot_control(desc, ecomp, desc_ptr);
237 
238 	switch (val) {
239 	case ENCLOSURE_SETTING_DISABLED:
240 		desc[3] &= 0xdf;
241 		break;
242 	case ENCLOSURE_SETTING_ENABLED:
243 		desc[3] |= 0x20;
244 		break;
245 	default:
246 		/* SES doesn't do the SGPIO blink settings */
247 		return -EINVAL;
248 	}
249 
250 	return ses_set_page2_descriptor(edev, ecomp, desc);
251 }
252 
253 static void ses_get_status(struct enclosure_device *edev,
254 			   struct enclosure_component *ecomp)
255 {
256 	unsigned char *desc;
257 
258 	if (!ses_page2_supported(edev)) {
259 		ecomp->status = 0;
260 		return;
261 	}
262 	desc = ses_get_page2_descriptor(edev, ecomp);
263 	if (desc)
264 		ecomp->status = (desc[0] & 0x0f);
265 }
266 
267 static void ses_get_locate(struct enclosure_device *edev,
268 			   struct enclosure_component *ecomp)
269 {
270 	unsigned char *desc;
271 
272 	if (!ses_page2_supported(edev)) {
273 		ecomp->locate = 0;
274 		return;
275 	}
276 	desc = ses_get_page2_descriptor(edev, ecomp);
277 	if (desc)
278 		ecomp->locate = (desc[2] & 0x02) ? 1 : 0;
279 }
280 
281 static int ses_set_locate(struct enclosure_device *edev,
282 			  struct enclosure_component *ecomp,
283 			  enum enclosure_component_setting val)
284 {
285 	unsigned char desc[4];
286 	unsigned char *desc_ptr;
287 
288 	if (!ses_page2_supported(edev))
289 		return -EINVAL;
290 
291 	desc_ptr = ses_get_page2_descriptor(edev, ecomp);
292 
293 	if (!desc_ptr)
294 		return -EIO;
295 
296 	init_device_slot_control(desc, ecomp, desc_ptr);
297 
298 	switch (val) {
299 	case ENCLOSURE_SETTING_DISABLED:
300 		desc[2] &= 0xfd;
301 		break;
302 	case ENCLOSURE_SETTING_ENABLED:
303 		desc[2] |= 0x02;
304 		break;
305 	default:
306 		/* SES doesn't do the SGPIO blink settings */
307 		return -EINVAL;
308 	}
309 	return ses_set_page2_descriptor(edev, ecomp, desc);
310 }
311 
312 static int ses_set_active(struct enclosure_device *edev,
313 			  struct enclosure_component *ecomp,
314 			  enum enclosure_component_setting val)
315 {
316 	unsigned char desc[4];
317 	unsigned char *desc_ptr;
318 
319 	if (!ses_page2_supported(edev))
320 		return -EINVAL;
321 
322 	desc_ptr = ses_get_page2_descriptor(edev, ecomp);
323 
324 	if (!desc_ptr)
325 		return -EIO;
326 
327 	init_device_slot_control(desc, ecomp, desc_ptr);
328 
329 	switch (val) {
330 	case ENCLOSURE_SETTING_DISABLED:
331 		desc[2] &= 0x7f;
332 		ecomp->active = 0;
333 		break;
334 	case ENCLOSURE_SETTING_ENABLED:
335 		desc[2] |= 0x80;
336 		ecomp->active = 1;
337 		break;
338 	default:
339 		/* SES doesn't do the SGPIO blink settings */
340 		return -EINVAL;
341 	}
342 	return ses_set_page2_descriptor(edev, ecomp, desc);
343 }
344 
345 static int ses_show_id(struct enclosure_device *edev, char *buf)
346 {
347 	struct ses_device *ses_dev = edev->scratch;
348 	unsigned long long id = get_unaligned_be64(ses_dev->page1+8+4);
349 
350 	return sprintf(buf, "%#llx\n", id);
351 }
352 
353 static void ses_get_power_status(struct enclosure_device *edev,
354 				 struct enclosure_component *ecomp)
355 {
356 	unsigned char *desc;
357 
358 	if (!ses_page2_supported(edev)) {
359 		ecomp->power_status = 0;
360 		return;
361 	}
362 
363 	desc = ses_get_page2_descriptor(edev, ecomp);
364 	if (desc)
365 		ecomp->power_status = (desc[3] & 0x10) ? 0 : 1;
366 }
367 
368 static int ses_set_power_status(struct enclosure_device *edev,
369 				struct enclosure_component *ecomp,
370 				int val)
371 {
372 	unsigned char desc[4];
373 	unsigned char *desc_ptr;
374 
375 	if (!ses_page2_supported(edev))
376 		return -EINVAL;
377 
378 	desc_ptr = ses_get_page2_descriptor(edev, ecomp);
379 
380 	if (!desc_ptr)
381 		return -EIO;
382 
383 	init_device_slot_control(desc, ecomp, desc_ptr);
384 
385 	switch (val) {
386 	/* power = 1 is device_off = 0 and vice versa */
387 	case 0:
388 		desc[3] |= 0x10;
389 		break;
390 	case 1:
391 		desc[3] &= 0xef;
392 		break;
393 	default:
394 		return -EINVAL;
395 	}
396 	ecomp->power_status = val;
397 	return ses_set_page2_descriptor(edev, ecomp, desc);
398 }
399 
400 static struct enclosure_component_callbacks ses_enclosure_callbacks = {
401 	.get_fault		= ses_get_fault,
402 	.set_fault		= ses_set_fault,
403 	.get_status		= ses_get_status,
404 	.get_locate		= ses_get_locate,
405 	.set_locate		= ses_set_locate,
406 	.get_power_status	= ses_get_power_status,
407 	.set_power_status	= ses_set_power_status,
408 	.set_active		= ses_set_active,
409 	.show_id		= ses_show_id,
410 };
411 
412 struct ses_host_edev {
413 	struct Scsi_Host *shost;
414 	struct enclosure_device *edev;
415 };
416 
417 #if 0
418 int ses_match_host(struct enclosure_device *edev, void *data)
419 {
420 	struct ses_host_edev *sed = data;
421 	struct scsi_device *sdev;
422 
423 	if (!scsi_is_sdev_device(edev->edev.parent))
424 		return 0;
425 
426 	sdev = to_scsi_device(edev->edev.parent);
427 
428 	if (sdev->host != sed->shost)
429 		return 0;
430 
431 	sed->edev = edev;
432 	return 1;
433 }
434 #endif  /*  0  */
435 
436 static void ses_process_descriptor(struct enclosure_component *ecomp,
437 				   unsigned char *desc)
438 {
439 	int eip = desc[0] & 0x10;
440 	int invalid = desc[0] & 0x80;
441 	enum scsi_protocol proto = desc[0] & 0x0f;
442 	u64 addr = 0;
443 	int slot = -1;
444 	struct ses_component *scomp = ecomp->scratch;
445 	unsigned char *d;
446 
447 	if (invalid)
448 		return;
449 
450 	switch (proto) {
451 	case SCSI_PROTOCOL_FCP:
452 		if (eip) {
453 			d = desc + 4;
454 			slot = d[3];
455 		}
456 		break;
457 	case SCSI_PROTOCOL_SAS:
458 		if (eip) {
459 			d = desc + 4;
460 			slot = d[3];
461 			d = desc + 8;
462 		} else
463 			d = desc + 4;
464 		/* only take the phy0 addr */
465 		addr = (u64)d[12] << 56 |
466 			(u64)d[13] << 48 |
467 			(u64)d[14] << 40 |
468 			(u64)d[15] << 32 |
469 			(u64)d[16] << 24 |
470 			(u64)d[17] << 16 |
471 			(u64)d[18] << 8 |
472 			(u64)d[19];
473 		break;
474 	default:
475 		/* FIXME: Need to add more protocols than just SAS */
476 		break;
477 	}
478 	ecomp->slot = slot;
479 	scomp->addr = addr;
480 }
481 
482 struct efd {
483 	u64 addr;
484 	struct device *dev;
485 };
486 
487 static int ses_enclosure_find_by_addr(struct enclosure_device *edev,
488 				      void *data)
489 {
490 	struct efd *efd = data;
491 	int i;
492 	struct ses_component *scomp;
493 
494 	if (!edev->component[0].scratch)
495 		return 0;
496 
497 	for (i = 0; i < edev->components; i++) {
498 		scomp = edev->component[i].scratch;
499 		if (scomp->addr != efd->addr)
500 			continue;
501 
502 		if (enclosure_add_device(edev, i, efd->dev) == 0)
503 			kobject_uevent(&efd->dev->kobj, KOBJ_CHANGE);
504 		return 1;
505 	}
506 	return 0;
507 }
508 
509 #define INIT_ALLOC_SIZE 32
510 
511 static void ses_enclosure_data_process(struct enclosure_device *edev,
512 				       struct scsi_device *sdev,
513 				       int create)
514 {
515 	u32 result;
516 	unsigned char *buf = NULL, *type_ptr, *desc_ptr, *addl_desc_ptr = NULL;
517 	int i, j, page7_len, len, components;
518 	struct ses_device *ses_dev = edev->scratch;
519 	int types = ses_dev->page1_num_types;
520 	unsigned char *hdr_buf = kzalloc(INIT_ALLOC_SIZE, GFP_KERNEL);
521 
522 	if (!hdr_buf)
523 		goto simple_populate;
524 
525 	/* re-read page 10 */
526 	if (ses_dev->page10)
527 		ses_recv_diag(sdev, 10, ses_dev->page10, ses_dev->page10_len);
528 	/* Page 7 for the descriptors is optional */
529 	result = ses_recv_diag(sdev, 7, hdr_buf, INIT_ALLOC_SIZE);
530 	if (result)
531 		goto simple_populate;
532 
533 	page7_len = len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
534 	/* add 1 for trailing '\0' we'll use */
535 	buf = kzalloc(len + 1, GFP_KERNEL);
536 	if (!buf)
537 		goto simple_populate;
538 	result = ses_recv_diag(sdev, 7, buf, len);
539 	if (result) {
540  simple_populate:
541 		kfree(buf);
542 		buf = NULL;
543 		desc_ptr = NULL;
544 		len = 0;
545 		page7_len = 0;
546 	} else {
547 		desc_ptr = buf + 8;
548 		len = (desc_ptr[2] << 8) + desc_ptr[3];
549 		/* skip past overall descriptor */
550 		desc_ptr += len + 4;
551 	}
552 	if (ses_dev->page10)
553 		addl_desc_ptr = ses_dev->page10 + 8;
554 	type_ptr = ses_dev->page1_types;
555 	components = 0;
556 	for (i = 0; i < types; i++, type_ptr += 4) {
557 		for (j = 0; j < type_ptr[1]; j++) {
558 			char *name = NULL;
559 			struct enclosure_component *ecomp;
560 
561 			if (desc_ptr) {
562 				if (desc_ptr >= buf + page7_len) {
563 					desc_ptr = NULL;
564 				} else {
565 					len = (desc_ptr[2] << 8) + desc_ptr[3];
566 					desc_ptr += 4;
567 					/* Add trailing zero - pushes into
568 					 * reserved space */
569 					desc_ptr[len] = '\0';
570 					name = desc_ptr;
571 				}
572 			}
573 			if (type_ptr[0] == ENCLOSURE_COMPONENT_DEVICE ||
574 			    type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE) {
575 
576 				if (create)
577 					ecomp =	enclosure_component_alloc(
578 						edev,
579 						components++,
580 						type_ptr[0],
581 						name);
582 				else
583 					ecomp = &edev->component[components++];
584 
585 				if (!IS_ERR(ecomp)) {
586 					if (addl_desc_ptr)
587 						ses_process_descriptor(
588 							ecomp,
589 							addl_desc_ptr);
590 					if (create)
591 						enclosure_component_register(
592 							ecomp);
593 				}
594 			}
595 			if (desc_ptr)
596 				desc_ptr += len;
597 
598 			if (addl_desc_ptr &&
599 			    /* only find additional descriptions for specific devices */
600 			    (type_ptr[0] == ENCLOSURE_COMPONENT_DEVICE ||
601 			     type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE ||
602 			     type_ptr[0] == ENCLOSURE_COMPONENT_SAS_EXPANDER ||
603 			     /* these elements are optional */
604 			     type_ptr[0] == ENCLOSURE_COMPONENT_SCSI_TARGET_PORT ||
605 			     type_ptr[0] == ENCLOSURE_COMPONENT_SCSI_INITIATOR_PORT ||
606 			     type_ptr[0] == ENCLOSURE_COMPONENT_CONTROLLER_ELECTRONICS))
607 				addl_desc_ptr += addl_desc_ptr[1] + 2;
608 
609 		}
610 	}
611 	kfree(buf);
612 	kfree(hdr_buf);
613 }
614 
615 static void ses_match_to_enclosure(struct enclosure_device *edev,
616 				   struct scsi_device *sdev,
617 				   int refresh)
618 {
619 	struct scsi_device *edev_sdev = to_scsi_device(edev->edev.parent);
620 	struct efd efd = {
621 		.addr = 0,
622 	};
623 
624 	if (refresh)
625 		ses_enclosure_data_process(edev, edev_sdev, 0);
626 
627 	if (scsi_is_sas_rphy(sdev->sdev_target->dev.parent))
628 		efd.addr = sas_get_address(sdev);
629 
630 	if (efd.addr) {
631 		efd.dev = &sdev->sdev_gendev;
632 
633 		enclosure_for_each_device(ses_enclosure_find_by_addr, &efd);
634 	}
635 }
636 
637 static int ses_intf_add(struct device *cdev,
638 			struct class_interface *intf)
639 {
640 	struct scsi_device *sdev = to_scsi_device(cdev->parent);
641 	struct scsi_device *tmp_sdev;
642 	unsigned char *buf = NULL, *hdr_buf, *type_ptr, page;
643 	struct ses_device *ses_dev;
644 	u32 result;
645 	int i, types, len, components = 0;
646 	int err = -ENOMEM;
647 	int num_enclosures;
648 	struct enclosure_device *edev;
649 	struct ses_component *scomp = NULL;
650 
651 	if (!scsi_device_enclosure(sdev)) {
652 		/* not an enclosure, but might be in one */
653 		struct enclosure_device *prev = NULL;
654 
655 		while ((edev = enclosure_find(&sdev->host->shost_gendev, prev)) != NULL) {
656 			ses_match_to_enclosure(edev, sdev, 1);
657 			prev = edev;
658 		}
659 		return -ENODEV;
660 	}
661 
662 	/* TYPE_ENCLOSURE prints a message in probe */
663 	if (sdev->type != TYPE_ENCLOSURE)
664 		sdev_printk(KERN_NOTICE, sdev, "Embedded Enclosure Device\n");
665 
666 	ses_dev = kzalloc(sizeof(*ses_dev), GFP_KERNEL);
667 	hdr_buf = kzalloc(INIT_ALLOC_SIZE, GFP_KERNEL);
668 	if (!hdr_buf || !ses_dev)
669 		goto err_init_free;
670 
671 	page = 1;
672 	result = ses_recv_diag(sdev, page, hdr_buf, INIT_ALLOC_SIZE);
673 	if (result)
674 		goto recv_failed;
675 
676 	len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
677 	buf = kzalloc(len, GFP_KERNEL);
678 	if (!buf)
679 		goto err_free;
680 
681 	result = ses_recv_diag(sdev, page, buf, len);
682 	if (result)
683 		goto recv_failed;
684 
685 	types = 0;
686 
687 	/* we always have one main enclosure and the rest are referred
688 	 * to as secondary subenclosures */
689 	num_enclosures = buf[1] + 1;
690 
691 	/* begin at the enclosure descriptor */
692 	type_ptr = buf + 8;
693 	/* skip all the enclosure descriptors */
694 	for (i = 0; i < num_enclosures && type_ptr < buf + len; i++) {
695 		types += type_ptr[2];
696 		type_ptr += type_ptr[3] + 4;
697 	}
698 
699 	ses_dev->page1_types = type_ptr;
700 	ses_dev->page1_num_types = types;
701 
702 	for (i = 0; i < types && type_ptr < buf + len; i++, type_ptr += 4) {
703 		if (type_ptr[0] == ENCLOSURE_COMPONENT_DEVICE ||
704 		    type_ptr[0] == ENCLOSURE_COMPONENT_ARRAY_DEVICE)
705 			components += type_ptr[1];
706 	}
707 	ses_dev->page1 = buf;
708 	ses_dev->page1_len = len;
709 	buf = NULL;
710 
711 	page = 2;
712 	result = ses_recv_diag(sdev, page, hdr_buf, INIT_ALLOC_SIZE);
713 	if (result)
714 		goto page2_not_supported;
715 
716 	len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
717 	buf = kzalloc(len, GFP_KERNEL);
718 	if (!buf)
719 		goto err_free;
720 
721 	/* make sure getting page 2 actually works */
722 	result = ses_recv_diag(sdev, 2, buf, len);
723 	if (result)
724 		goto recv_failed;
725 	ses_dev->page2 = buf;
726 	ses_dev->page2_len = len;
727 	buf = NULL;
728 
729 	/* The additional information page --- allows us
730 	 * to match up the devices */
731 	page = 10;
732 	result = ses_recv_diag(sdev, page, hdr_buf, INIT_ALLOC_SIZE);
733 	if (!result) {
734 
735 		len = (hdr_buf[2] << 8) + hdr_buf[3] + 4;
736 		buf = kzalloc(len, GFP_KERNEL);
737 		if (!buf)
738 			goto err_free;
739 
740 		result = ses_recv_diag(sdev, page, buf, len);
741 		if (result)
742 			goto recv_failed;
743 		ses_dev->page10 = buf;
744 		ses_dev->page10_len = len;
745 		buf = NULL;
746 	}
747 page2_not_supported:
748 	scomp = kcalloc(components, sizeof(struct ses_component), GFP_KERNEL);
749 	if (!scomp)
750 		goto err_free;
751 
752 	edev = enclosure_register(cdev->parent, dev_name(&sdev->sdev_gendev),
753 				  components, &ses_enclosure_callbacks);
754 	if (IS_ERR(edev)) {
755 		err = PTR_ERR(edev);
756 		goto err_free;
757 	}
758 
759 	kfree(hdr_buf);
760 
761 	edev->scratch = ses_dev;
762 	for (i = 0; i < components; i++)
763 		edev->component[i].scratch = scomp + i;
764 
765 	ses_enclosure_data_process(edev, sdev, 1);
766 
767 	/* see if there are any devices matching before
768 	 * we found the enclosure */
769 	shost_for_each_device(tmp_sdev, sdev->host) {
770 		if (tmp_sdev->lun != 0 || scsi_device_enclosure(tmp_sdev))
771 			continue;
772 		ses_match_to_enclosure(edev, tmp_sdev, 0);
773 	}
774 
775 	return 0;
776 
777  recv_failed:
778 	sdev_printk(KERN_ERR, sdev, "Failed to get diagnostic page 0x%x\n",
779 		    page);
780 	err = -ENODEV;
781  err_free:
782 	kfree(buf);
783 	kfree(scomp);
784 	kfree(ses_dev->page10);
785 	kfree(ses_dev->page2);
786 	kfree(ses_dev->page1);
787  err_init_free:
788 	kfree(ses_dev);
789 	kfree(hdr_buf);
790 	sdev_printk(KERN_ERR, sdev, "Failed to bind enclosure %d\n", err);
791 	return err;
792 }
793 
794 static int ses_remove(struct device *dev)
795 {
796 	return 0;
797 }
798 
799 static void ses_intf_remove_component(struct scsi_device *sdev)
800 {
801 	struct enclosure_device *edev, *prev = NULL;
802 
803 	while ((edev = enclosure_find(&sdev->host->shost_gendev, prev)) != NULL) {
804 		prev = edev;
805 		if (!enclosure_remove_device(edev, &sdev->sdev_gendev))
806 			break;
807 	}
808 	if (edev)
809 		put_device(&edev->edev);
810 }
811 
812 static void ses_intf_remove_enclosure(struct scsi_device *sdev)
813 {
814 	struct enclosure_device *edev;
815 	struct ses_device *ses_dev;
816 
817 	/*  exact match to this enclosure */
818 	edev = enclosure_find(&sdev->sdev_gendev, NULL);
819 	if (!edev)
820 		return;
821 
822 	ses_dev = edev->scratch;
823 	edev->scratch = NULL;
824 
825 	kfree(ses_dev->page10);
826 	kfree(ses_dev->page1);
827 	kfree(ses_dev->page2);
828 	kfree(ses_dev);
829 
830 	kfree(edev->component[0].scratch);
831 
832 	put_device(&edev->edev);
833 	enclosure_unregister(edev);
834 }
835 
836 static void ses_intf_remove(struct device *cdev,
837 			    struct class_interface *intf)
838 {
839 	struct scsi_device *sdev = to_scsi_device(cdev->parent);
840 
841 	if (!scsi_device_enclosure(sdev))
842 		ses_intf_remove_component(sdev);
843 	else
844 		ses_intf_remove_enclosure(sdev);
845 }
846 
847 static struct class_interface ses_interface = {
848 	.add_dev	= ses_intf_add,
849 	.remove_dev	= ses_intf_remove,
850 };
851 
852 static struct scsi_driver ses_template = {
853 	.gendrv = {
854 		.name		= "ses",
855 		.owner		= THIS_MODULE,
856 		.probe		= ses_probe,
857 		.remove		= ses_remove,
858 	},
859 };
860 
861 static int __init ses_init(void)
862 {
863 	int err;
864 
865 	err = scsi_register_interface(&ses_interface);
866 	if (err)
867 		return err;
868 
869 	err = scsi_register_driver(&ses_template.gendrv);
870 	if (err)
871 		goto out_unreg;
872 
873 	return 0;
874 
875  out_unreg:
876 	scsi_unregister_interface(&ses_interface);
877 	return err;
878 }
879 
880 static void __exit ses_exit(void)
881 {
882 	scsi_unregister_driver(&ses_template.gendrv);
883 	scsi_unregister_interface(&ses_interface);
884 }
885 
886 module_init(ses_init);
887 module_exit(ses_exit);
888 
889 MODULE_ALIAS_SCSI_DEVICE(TYPE_ENCLOSURE);
890 
891 MODULE_AUTHOR("James Bottomley");
892 MODULE_DESCRIPTION("SCSI Enclosure Services (ses) driver");
893 MODULE_LICENSE("GPL v2");
894