xref: /openbmc/linux/drivers/firmware/iscsi_ibft.c (revision 275876e2)
1 /*
2  *  Copyright 2007-2010 Red Hat, Inc.
3  *  by Peter Jones <pjones@redhat.com>
4  *  Copyright 2008 IBM, Inc.
5  *  by Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
6  *  Copyright 2008
7  *  by Konrad Rzeszutek <ketuzsezr@darnok.org>
8  *
9  * This code exposes the iSCSI Boot Format Table to userland via sysfs.
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License v2.0 as published by
13  * the Free Software Foundation
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * Changelog:
21  *
22  *  06 Jan 2010 - Peter Jones <pjones@redhat.com>
23  *    New changelog entries are in the git log from now on.  Not here.
24  *
25  *  14 Mar 2008 - Konrad Rzeszutek <ketuzsezr@darnok.org>
26  *    Updated comments and copyrights. (v0.4.9)
27  *
28  *  11 Feb 2008 - Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
29  *    Converted to using ibft_addr. (v0.4.8)
30  *
31  *   8 Feb 2008 - Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
32  *    Combined two functions in one: reserve_ibft_region. (v0.4.7)
33  *
34  *  30 Jan 2008 - Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
35  *   Added logic to handle IPv6 addresses. (v0.4.6)
36  *
37  *  25 Jan 2008 - Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
38  *   Added logic to handle badly not-to-spec iBFT. (v0.4.5)
39  *
40  *   4 Jan 2008 - Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
41  *   Added __init to function declarations. (v0.4.4)
42  *
43  *  21 Dec 2007 - Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
44  *   Updated kobject registration, combined unregister functions in one
45  *   and code and style cleanup. (v0.4.3)
46  *
47  *   5 Dec 2007 - Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
48  *   Added end-markers to enums and re-organized kobject registration. (v0.4.2)
49  *
50  *   4 Dec 2007 - Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
51  *   Created 'device' sysfs link to the NIC and style cleanup. (v0.4.1)
52  *
53  *  28 Nov 2007 - Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
54  *   Added sysfs-ibft documentation, moved 'find_ibft' function to
55  *   in its own file and added text attributes for every struct field.  (v0.4)
56  *
57  *  21 Nov 2007 - Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
58  *   Added text attributes emulating OpenFirmware /proc/device-tree naming.
59  *   Removed binary /sysfs interface (v0.3)
60  *
61  *  29 Aug 2007 - Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
62  *   Added functionality in setup.c to reserve iBFT region. (v0.2)
63  *
64  *  27 Aug 2007 - Konrad Rzeszutek <konradr@linux.vnet.ibm.com>
65  *   First version exposing iBFT data via a binary /sysfs. (v0.1)
66  *
67  */
68 
69 
70 #include <linux/blkdev.h>
71 #include <linux/capability.h>
72 #include <linux/ctype.h>
73 #include <linux/device.h>
74 #include <linux/err.h>
75 #include <linux/init.h>
76 #include <linux/iscsi_ibft.h>
77 #include <linux/limits.h>
78 #include <linux/module.h>
79 #include <linux/pci.h>
80 #include <linux/slab.h>
81 #include <linux/stat.h>
82 #include <linux/string.h>
83 #include <linux/types.h>
84 #include <linux/acpi.h>
85 #include <linux/iscsi_boot_sysfs.h>
86 
87 #define IBFT_ISCSI_VERSION "0.5.0"
88 #define IBFT_ISCSI_DATE "2010-Feb-25"
89 
90 MODULE_AUTHOR("Peter Jones <pjones@redhat.com> and "
91 	      "Konrad Rzeszutek <ketuzsezr@darnok.org>");
92 MODULE_DESCRIPTION("sysfs interface to BIOS iBFT information");
93 MODULE_LICENSE("GPL");
94 MODULE_VERSION(IBFT_ISCSI_VERSION);
95 
96 struct ibft_hdr {
97 	u8 id;
98 	u8 version;
99 	u16 length;
100 	u8 index;
101 	u8 flags;
102 } __attribute__((__packed__));
103 
104 struct ibft_control {
105 	struct ibft_hdr hdr;
106 	u16 extensions;
107 	u16 initiator_off;
108 	u16 nic0_off;
109 	u16 tgt0_off;
110 	u16 nic1_off;
111 	u16 tgt1_off;
112 } __attribute__((__packed__));
113 
114 struct ibft_initiator {
115 	struct ibft_hdr hdr;
116 	char isns_server[16];
117 	char slp_server[16];
118 	char pri_radius_server[16];
119 	char sec_radius_server[16];
120 	u16 initiator_name_len;
121 	u16 initiator_name_off;
122 } __attribute__((__packed__));
123 
124 struct ibft_nic {
125 	struct ibft_hdr hdr;
126 	char ip_addr[16];
127 	u8 subnet_mask_prefix;
128 	u8 origin;
129 	char gateway[16];
130 	char primary_dns[16];
131 	char secondary_dns[16];
132 	char dhcp[16];
133 	u16 vlan;
134 	char mac[6];
135 	u16 pci_bdf;
136 	u16 hostname_len;
137 	u16 hostname_off;
138 } __attribute__((__packed__));
139 
140 struct ibft_tgt {
141 	struct ibft_hdr hdr;
142 	char ip_addr[16];
143 	u16 port;
144 	char lun[8];
145 	u8 chap_type;
146 	u8 nic_assoc;
147 	u16 tgt_name_len;
148 	u16 tgt_name_off;
149 	u16 chap_name_len;
150 	u16 chap_name_off;
151 	u16 chap_secret_len;
152 	u16 chap_secret_off;
153 	u16 rev_chap_name_len;
154 	u16 rev_chap_name_off;
155 	u16 rev_chap_secret_len;
156 	u16 rev_chap_secret_off;
157 } __attribute__((__packed__));
158 
159 /*
160  * The kobject different types and its names.
161  *
162 */
163 enum ibft_id {
164 	id_reserved = 0, /* We don't support. */
165 	id_control = 1, /* Should show up only once and is not exported. */
166 	id_initiator = 2,
167 	id_nic = 3,
168 	id_target = 4,
169 	id_extensions = 5, /* We don't support. */
170 	id_end_marker,
171 };
172 
173 /*
174  * The kobject and attribute structures.
175  */
176 
177 struct ibft_kobject {
178 	struct acpi_table_ibft *header;
179 	union {
180 		struct ibft_initiator *initiator;
181 		struct ibft_nic *nic;
182 		struct ibft_tgt *tgt;
183 		struct ibft_hdr *hdr;
184 	};
185 };
186 
187 static struct iscsi_boot_kset *boot_kset;
188 
189 static const char nulls[16];
190 
191 /*
192  * Helper functions to parse data properly.
193  */
194 static ssize_t sprintf_ipaddr(char *buf, u8 *ip)
195 {
196 	char *str = buf;
197 
198 	if (ip[0] == 0 && ip[1] == 0 && ip[2] == 0 && ip[3] == 0 &&
199 	    ip[4] == 0 && ip[5] == 0 && ip[6] == 0 && ip[7] == 0 &&
200 	    ip[8] == 0 && ip[9] == 0 && ip[10] == 0xff && ip[11] == 0xff) {
201 		/*
202 		 * IPV4
203 		 */
204 		str += sprintf(buf, "%pI4", ip + 12);
205 	} else {
206 		/*
207 		 * IPv6
208 		 */
209 		str += sprintf(str, "%pI6", ip);
210 	}
211 	str += sprintf(str, "\n");
212 	return str - buf;
213 }
214 
215 static ssize_t sprintf_string(char *str, int len, char *buf)
216 {
217 	return sprintf(str, "%.*s\n", len, buf);
218 }
219 
220 /*
221  * Helper function to verify the IBFT header.
222  */
223 static int ibft_verify_hdr(char *t, struct ibft_hdr *hdr, int id, int length)
224 {
225 	if (hdr->id != id) {
226 		printk(KERN_ERR "iBFT error: We expected the %s " \
227 				"field header.id to have %d but " \
228 				"found %d instead!\n", t, id, hdr->id);
229 		return -ENODEV;
230 	}
231 	if (hdr->length != length) {
232 		printk(KERN_ERR "iBFT error: We expected the %s " \
233 				"field header.length to have %d but " \
234 				"found %d instead!\n", t, length, hdr->length);
235 		return -ENODEV;
236 	}
237 
238 	return 0;
239 }
240 
241 /*
242  *  Routines for parsing the iBFT data to be human readable.
243  */
244 static ssize_t ibft_attr_show_initiator(void *data, int type, char *buf)
245 {
246 	struct ibft_kobject *entry = data;
247 	struct ibft_initiator *initiator = entry->initiator;
248 	void *ibft_loc = entry->header;
249 	char *str = buf;
250 
251 	if (!initiator)
252 		return 0;
253 
254 	switch (type) {
255 	case ISCSI_BOOT_INI_INDEX:
256 		str += sprintf(str, "%d\n", initiator->hdr.index);
257 		break;
258 	case ISCSI_BOOT_INI_FLAGS:
259 		str += sprintf(str, "%d\n", initiator->hdr.flags);
260 		break;
261 	case ISCSI_BOOT_INI_ISNS_SERVER:
262 		str += sprintf_ipaddr(str, initiator->isns_server);
263 		break;
264 	case ISCSI_BOOT_INI_SLP_SERVER:
265 		str += sprintf_ipaddr(str, initiator->slp_server);
266 		break;
267 	case ISCSI_BOOT_INI_PRI_RADIUS_SERVER:
268 		str += sprintf_ipaddr(str, initiator->pri_radius_server);
269 		break;
270 	case ISCSI_BOOT_INI_SEC_RADIUS_SERVER:
271 		str += sprintf_ipaddr(str, initiator->sec_radius_server);
272 		break;
273 	case ISCSI_BOOT_INI_INITIATOR_NAME:
274 		str += sprintf_string(str, initiator->initiator_name_len,
275 				      (char *)ibft_loc +
276 				      initiator->initiator_name_off);
277 		break;
278 	default:
279 		break;
280 	}
281 
282 	return str - buf;
283 }
284 
285 static ssize_t ibft_attr_show_nic(void *data, int type, char *buf)
286 {
287 	struct ibft_kobject *entry = data;
288 	struct ibft_nic *nic = entry->nic;
289 	void *ibft_loc = entry->header;
290 	char *str = buf;
291 	__be32 val;
292 
293 	if (!nic)
294 		return 0;
295 
296 	switch (type) {
297 	case ISCSI_BOOT_ETH_INDEX:
298 		str += sprintf(str, "%d\n", nic->hdr.index);
299 		break;
300 	case ISCSI_BOOT_ETH_FLAGS:
301 		str += sprintf(str, "%d\n", nic->hdr.flags);
302 		break;
303 	case ISCSI_BOOT_ETH_IP_ADDR:
304 		str += sprintf_ipaddr(str, nic->ip_addr);
305 		break;
306 	case ISCSI_BOOT_ETH_SUBNET_MASK:
307 		val = cpu_to_be32(~((1 << (32-nic->subnet_mask_prefix))-1));
308 		str += sprintf(str, "%pI4", &val);
309 		break;
310 	case ISCSI_BOOT_ETH_ORIGIN:
311 		str += sprintf(str, "%d\n", nic->origin);
312 		break;
313 	case ISCSI_BOOT_ETH_GATEWAY:
314 		str += sprintf_ipaddr(str, nic->gateway);
315 		break;
316 	case ISCSI_BOOT_ETH_PRIMARY_DNS:
317 		str += sprintf_ipaddr(str, nic->primary_dns);
318 		break;
319 	case ISCSI_BOOT_ETH_SECONDARY_DNS:
320 		str += sprintf_ipaddr(str, nic->secondary_dns);
321 		break;
322 	case ISCSI_BOOT_ETH_DHCP:
323 		str += sprintf_ipaddr(str, nic->dhcp);
324 		break;
325 	case ISCSI_BOOT_ETH_VLAN:
326 		str += sprintf(str, "%d\n", nic->vlan);
327 		break;
328 	case ISCSI_BOOT_ETH_MAC:
329 		str += sprintf(str, "%pM\n", nic->mac);
330 		break;
331 	case ISCSI_BOOT_ETH_HOSTNAME:
332 		str += sprintf_string(str, nic->hostname_len,
333 				      (char *)ibft_loc + nic->hostname_off);
334 		break;
335 	default:
336 		break;
337 	}
338 
339 	return str - buf;
340 };
341 
342 static ssize_t ibft_attr_show_target(void *data, int type, char *buf)
343 {
344 	struct ibft_kobject *entry = data;
345 	struct ibft_tgt *tgt = entry->tgt;
346 	void *ibft_loc = entry->header;
347 	char *str = buf;
348 	int i;
349 
350 	if (!tgt)
351 		return 0;
352 
353 	switch (type) {
354 	case ISCSI_BOOT_TGT_INDEX:
355 		str += sprintf(str, "%d\n", tgt->hdr.index);
356 		break;
357 	case ISCSI_BOOT_TGT_FLAGS:
358 		str += sprintf(str, "%d\n", tgt->hdr.flags);
359 		break;
360 	case ISCSI_BOOT_TGT_IP_ADDR:
361 		str += sprintf_ipaddr(str, tgt->ip_addr);
362 		break;
363 	case ISCSI_BOOT_TGT_PORT:
364 		str += sprintf(str, "%d\n", tgt->port);
365 		break;
366 	case ISCSI_BOOT_TGT_LUN:
367 		for (i = 0; i < 8; i++)
368 			str += sprintf(str, "%x", (u8)tgt->lun[i]);
369 		str += sprintf(str, "\n");
370 		break;
371 	case ISCSI_BOOT_TGT_NIC_ASSOC:
372 		str += sprintf(str, "%d\n", tgt->nic_assoc);
373 		break;
374 	case ISCSI_BOOT_TGT_CHAP_TYPE:
375 		str += sprintf(str, "%d\n", tgt->chap_type);
376 		break;
377 	case ISCSI_BOOT_TGT_NAME:
378 		str += sprintf_string(str, tgt->tgt_name_len,
379 				      (char *)ibft_loc + tgt->tgt_name_off);
380 		break;
381 	case ISCSI_BOOT_TGT_CHAP_NAME:
382 		str += sprintf_string(str, tgt->chap_name_len,
383 				      (char *)ibft_loc + tgt->chap_name_off);
384 		break;
385 	case ISCSI_BOOT_TGT_CHAP_SECRET:
386 		str += sprintf_string(str, tgt->chap_secret_len,
387 				      (char *)ibft_loc + tgt->chap_secret_off);
388 		break;
389 	case ISCSI_BOOT_TGT_REV_CHAP_NAME:
390 		str += sprintf_string(str, tgt->rev_chap_name_len,
391 				      (char *)ibft_loc +
392 				      tgt->rev_chap_name_off);
393 		break;
394 	case ISCSI_BOOT_TGT_REV_CHAP_SECRET:
395 		str += sprintf_string(str, tgt->rev_chap_secret_len,
396 				      (char *)ibft_loc +
397 				      tgt->rev_chap_secret_off);
398 		break;
399 	default:
400 		break;
401 	}
402 
403 	return str - buf;
404 }
405 
406 static int __init ibft_check_device(void)
407 {
408 	int len;
409 	u8 *pos;
410 	u8 csum = 0;
411 
412 	len = ibft_addr->header.length;
413 
414 	/* Sanity checking of iBFT. */
415 	if (ibft_addr->header.revision != 1) {
416 		printk(KERN_ERR "iBFT module supports only revision 1, " \
417 				"while this is %d.\n",
418 				ibft_addr->header.revision);
419 		return -ENOENT;
420 	}
421 	for (pos = (u8 *)ibft_addr; pos < (u8 *)ibft_addr + len; pos++)
422 		csum += *pos;
423 
424 	if (csum) {
425 		printk(KERN_ERR "iBFT has incorrect checksum (0x%x)!\n", csum);
426 		return -ENOENT;
427 	}
428 
429 	return 0;
430 }
431 
432 /*
433  * Helper routiners to check to determine if the entry is valid
434  * in the proper iBFT structure.
435  */
436 static umode_t ibft_check_nic_for(void *data, int type)
437 {
438 	struct ibft_kobject *entry = data;
439 	struct ibft_nic *nic = entry->nic;
440 	umode_t rc = 0;
441 
442 	switch (type) {
443 	case ISCSI_BOOT_ETH_INDEX:
444 	case ISCSI_BOOT_ETH_FLAGS:
445 		rc = S_IRUGO;
446 		break;
447 	case ISCSI_BOOT_ETH_IP_ADDR:
448 		if (memcmp(nic->ip_addr, nulls, sizeof(nic->ip_addr)))
449 			rc = S_IRUGO;
450 		break;
451 	case ISCSI_BOOT_ETH_SUBNET_MASK:
452 		if (nic->subnet_mask_prefix)
453 			rc = S_IRUGO;
454 		break;
455 	case ISCSI_BOOT_ETH_ORIGIN:
456 		rc = S_IRUGO;
457 		break;
458 	case ISCSI_BOOT_ETH_GATEWAY:
459 		if (memcmp(nic->gateway, nulls, sizeof(nic->gateway)))
460 			rc = S_IRUGO;
461 		break;
462 	case ISCSI_BOOT_ETH_PRIMARY_DNS:
463 		if (memcmp(nic->primary_dns, nulls,
464 			   sizeof(nic->primary_dns)))
465 			rc = S_IRUGO;
466 		break;
467 	case ISCSI_BOOT_ETH_SECONDARY_DNS:
468 		if (memcmp(nic->secondary_dns, nulls,
469 			   sizeof(nic->secondary_dns)))
470 			rc = S_IRUGO;
471 		break;
472 	case ISCSI_BOOT_ETH_DHCP:
473 		if (memcmp(nic->dhcp, nulls, sizeof(nic->dhcp)))
474 			rc = S_IRUGO;
475 		break;
476 	case ISCSI_BOOT_ETH_VLAN:
477 	case ISCSI_BOOT_ETH_MAC:
478 		rc = S_IRUGO;
479 		break;
480 	case ISCSI_BOOT_ETH_HOSTNAME:
481 		if (nic->hostname_off)
482 			rc = S_IRUGO;
483 		break;
484 	default:
485 		break;
486 	}
487 
488 	return rc;
489 }
490 
491 static umode_t __init ibft_check_tgt_for(void *data, int type)
492 {
493 	struct ibft_kobject *entry = data;
494 	struct ibft_tgt *tgt = entry->tgt;
495 	umode_t rc = 0;
496 
497 	switch (type) {
498 	case ISCSI_BOOT_TGT_INDEX:
499 	case ISCSI_BOOT_TGT_FLAGS:
500 	case ISCSI_BOOT_TGT_IP_ADDR:
501 	case ISCSI_BOOT_TGT_PORT:
502 	case ISCSI_BOOT_TGT_LUN:
503 	case ISCSI_BOOT_TGT_NIC_ASSOC:
504 	case ISCSI_BOOT_TGT_CHAP_TYPE:
505 		rc = S_IRUGO;
506 	case ISCSI_BOOT_TGT_NAME:
507 		if (tgt->tgt_name_len)
508 			rc = S_IRUGO;
509 		break;
510 	case ISCSI_BOOT_TGT_CHAP_NAME:
511 	case ISCSI_BOOT_TGT_CHAP_SECRET:
512 		if (tgt->chap_name_len)
513 			rc = S_IRUGO;
514 		break;
515 	case ISCSI_BOOT_TGT_REV_CHAP_NAME:
516 	case ISCSI_BOOT_TGT_REV_CHAP_SECRET:
517 		if (tgt->rev_chap_name_len)
518 			rc = S_IRUGO;
519 		break;
520 	default:
521 		break;
522 	}
523 
524 	return rc;
525 }
526 
527 static umode_t __init ibft_check_initiator_for(void *data, int type)
528 {
529 	struct ibft_kobject *entry = data;
530 	struct ibft_initiator *init = entry->initiator;
531 	umode_t rc = 0;
532 
533 	switch (type) {
534 	case ISCSI_BOOT_INI_INDEX:
535 	case ISCSI_BOOT_INI_FLAGS:
536 		rc = S_IRUGO;
537 		break;
538 	case ISCSI_BOOT_INI_ISNS_SERVER:
539 		if (memcmp(init->isns_server, nulls,
540 			   sizeof(init->isns_server)))
541 			rc = S_IRUGO;
542 		break;
543 	case ISCSI_BOOT_INI_SLP_SERVER:
544 		if (memcmp(init->slp_server, nulls,
545 			   sizeof(init->slp_server)))
546 			rc = S_IRUGO;
547 		break;
548 	case ISCSI_BOOT_INI_PRI_RADIUS_SERVER:
549 		if (memcmp(init->pri_radius_server, nulls,
550 			   sizeof(init->pri_radius_server)))
551 			rc = S_IRUGO;
552 		break;
553 	case ISCSI_BOOT_INI_SEC_RADIUS_SERVER:
554 		if (memcmp(init->sec_radius_server, nulls,
555 			   sizeof(init->sec_radius_server)))
556 			rc = S_IRUGO;
557 		break;
558 	case ISCSI_BOOT_INI_INITIATOR_NAME:
559 		if (init->initiator_name_len)
560 			rc = S_IRUGO;
561 		break;
562 	default:
563 		break;
564 	}
565 
566 	return rc;
567 }
568 
569 static void ibft_kobj_release(void *data)
570 {
571 	kfree(data);
572 }
573 
574 /*
575  * Helper function for ibft_register_kobjects.
576  */
577 static int __init ibft_create_kobject(struct acpi_table_ibft *header,
578 				      struct ibft_hdr *hdr)
579 {
580 	struct iscsi_boot_kobj *boot_kobj = NULL;
581 	struct ibft_kobject *ibft_kobj = NULL;
582 	struct ibft_nic *nic = (struct ibft_nic *)hdr;
583 	struct pci_dev *pci_dev;
584 	int rc = 0;
585 
586 	ibft_kobj = kzalloc(sizeof(*ibft_kobj), GFP_KERNEL);
587 	if (!ibft_kobj)
588 		return -ENOMEM;
589 
590 	ibft_kobj->header = header;
591 	ibft_kobj->hdr = hdr;
592 
593 	switch (hdr->id) {
594 	case id_initiator:
595 		rc = ibft_verify_hdr("initiator", hdr, id_initiator,
596 				     sizeof(*ibft_kobj->initiator));
597 		if (rc)
598 			break;
599 
600 		boot_kobj = iscsi_boot_create_initiator(boot_kset, hdr->index,
601 						ibft_kobj,
602 						ibft_attr_show_initiator,
603 						ibft_check_initiator_for,
604 						ibft_kobj_release);
605 		if (!boot_kobj) {
606 			rc = -ENOMEM;
607 			goto free_ibft_obj;
608 		}
609 		break;
610 	case id_nic:
611 		rc = ibft_verify_hdr("ethernet", hdr, id_nic,
612 				     sizeof(*ibft_kobj->nic));
613 		if (rc)
614 			break;
615 
616 		boot_kobj = iscsi_boot_create_ethernet(boot_kset, hdr->index,
617 						       ibft_kobj,
618 						       ibft_attr_show_nic,
619 						       ibft_check_nic_for,
620 						       ibft_kobj_release);
621 		if (!boot_kobj) {
622 			rc = -ENOMEM;
623 			goto free_ibft_obj;
624 		}
625 		break;
626 	case id_target:
627 		rc = ibft_verify_hdr("target", hdr, id_target,
628 				     sizeof(*ibft_kobj->tgt));
629 		if (rc)
630 			break;
631 
632 		boot_kobj = iscsi_boot_create_target(boot_kset, hdr->index,
633 						     ibft_kobj,
634 						     ibft_attr_show_target,
635 						     ibft_check_tgt_for,
636 						     ibft_kobj_release);
637 		if (!boot_kobj) {
638 			rc = -ENOMEM;
639 			goto free_ibft_obj;
640 		}
641 		break;
642 	case id_reserved:
643 	case id_control:
644 	case id_extensions:
645 		/* Fields which we don't support. Ignore them */
646 		rc = 1;
647 		break;
648 	default:
649 		printk(KERN_ERR "iBFT has unknown structure type (%d). " \
650 				"Report this bug to %.6s!\n", hdr->id,
651 				header->header.oem_id);
652 		rc = 1;
653 		break;
654 	}
655 
656 	if (rc) {
657 		/* Skip adding this kobject, but exit with non-fatal error. */
658 		rc = 0;
659 		goto free_ibft_obj;
660 	}
661 
662 	if (hdr->id == id_nic) {
663 		/*
664 		* We don't search for the device in other domains than
665 		* zero. This is because on x86 platforms the BIOS
666 		* executes only devices which are in domain 0. Furthermore, the
667 		* iBFT spec doesn't have a domain id field :-(
668 		*/
669 		pci_dev = pci_get_bus_and_slot((nic->pci_bdf & 0xff00) >> 8,
670 					       (nic->pci_bdf & 0xff));
671 		if (pci_dev) {
672 			rc = sysfs_create_link(&boot_kobj->kobj,
673 					       &pci_dev->dev.kobj, "device");
674 			pci_dev_put(pci_dev);
675 		}
676 	}
677 	return 0;
678 
679 free_ibft_obj:
680 	kfree(ibft_kobj);
681 	return rc;
682 }
683 
684 /*
685  * Scan the IBFT table structure for the NIC and Target fields. When
686  * found add them on the passed-in list. We do not support the other
687  * fields at this point, so they are skipped.
688  */
689 static int __init ibft_register_kobjects(struct acpi_table_ibft *header)
690 {
691 	struct ibft_control *control = NULL;
692 	void *ptr, *end;
693 	int rc = 0;
694 	u16 offset;
695 	u16 eot_offset;
696 
697 	control = (void *)header + sizeof(*header);
698 	end = (void *)control + control->hdr.length;
699 	eot_offset = (void *)header + header->header.length - (void *)control;
700 	rc = ibft_verify_hdr("control", (struct ibft_hdr *)control, id_control,
701 			     sizeof(*control));
702 
703 	/* iBFT table safety checking */
704 	rc |= ((control->hdr.index) ? -ENODEV : 0);
705 	if (rc) {
706 		printk(KERN_ERR "iBFT error: Control header is invalid!\n");
707 		return rc;
708 	}
709 	for (ptr = &control->initiator_off; ptr < end; ptr += sizeof(u16)) {
710 		offset = *(u16 *)ptr;
711 		if (offset && offset < header->header.length &&
712 						offset < eot_offset) {
713 			rc = ibft_create_kobject(header,
714 						 (void *)header + offset);
715 			if (rc)
716 				break;
717 		}
718 	}
719 
720 	return rc;
721 }
722 
723 static void ibft_unregister(void)
724 {
725 	struct iscsi_boot_kobj *boot_kobj, *tmp_kobj;
726 	struct ibft_kobject *ibft_kobj;
727 
728 	list_for_each_entry_safe(boot_kobj, tmp_kobj,
729 				 &boot_kset->kobj_list, list) {
730 		ibft_kobj = boot_kobj->data;
731 		if (ibft_kobj->hdr->id == id_nic)
732 			sysfs_remove_link(&boot_kobj->kobj, "device");
733 	};
734 }
735 
736 static void ibft_cleanup(void)
737 {
738 	if (boot_kset) {
739 		ibft_unregister();
740 		iscsi_boot_destroy_kset(boot_kset);
741 	}
742 }
743 
744 static void __exit ibft_exit(void)
745 {
746 	ibft_cleanup();
747 }
748 
749 #ifdef CONFIG_ACPI
750 static const struct {
751 	char *sign;
752 } ibft_signs[] = {
753 	/*
754 	 * One spec says "IBFT", the other says "iBFT". We have to check
755 	 * for both.
756 	 */
757 	{ ACPI_SIG_IBFT },
758 	{ "iBFT" },
759 	{ "BIFT" },	/* Broadcom iSCSI Offload */
760 };
761 
762 static void __init acpi_find_ibft_region(void)
763 {
764 	int i;
765 	struct acpi_table_header *table = NULL;
766 
767 	if (acpi_disabled)
768 		return;
769 
770 	for (i = 0; i < ARRAY_SIZE(ibft_signs) && !ibft_addr; i++) {
771 		acpi_get_table(ibft_signs[i].sign, 0, &table);
772 		ibft_addr = (struct acpi_table_ibft *)table;
773 	}
774 }
775 #else
776 static void __init acpi_find_ibft_region(void)
777 {
778 }
779 #endif
780 
781 /*
782  * ibft_init() - creates sysfs tree entries for the iBFT data.
783  */
784 static int __init ibft_init(void)
785 {
786 	int rc = 0;
787 
788 	/*
789 	   As on UEFI systems the setup_arch()/find_ibft_region()
790 	   is called before ACPI tables are parsed and it only does
791 	   legacy finding.
792 	*/
793 	if (!ibft_addr)
794 		acpi_find_ibft_region();
795 
796 	if (ibft_addr) {
797 		pr_info("iBFT detected.\n");
798 
799 		rc = ibft_check_device();
800 		if (rc)
801 			return rc;
802 
803 		boot_kset = iscsi_boot_create_kset("ibft");
804 		if (!boot_kset)
805 			return -ENOMEM;
806 
807 		/* Scan the IBFT for data and register the kobjects. */
808 		rc = ibft_register_kobjects(ibft_addr);
809 		if (rc)
810 			goto out_free;
811 	} else
812 		printk(KERN_INFO "No iBFT detected.\n");
813 
814 	return 0;
815 
816 out_free:
817 	ibft_cleanup();
818 	return rc;
819 }
820 
821 module_init(ibft_init);
822 module_exit(ibft_exit);
823