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OMAPDSS: VENC: fix NULL pointer dereference in DSS2 VENC sysfs debug attr on OMAP4
[zen-stable.git] / drivers / s390 / char / sclp_cmd.c
blob0b54a91f8dcd2aa23d23634910fb92a683cea949
1 /*
2 * Copyright IBM Corp. 2007, 2009
3 *
4 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
5 * Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
6 */
7
8 #define KMSG_COMPONENT "sclp_cmd"
9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
10
11 #include <linux/completion.h>
12 #include <linux/init.h>
13 #include <linux/errno.h>
14 #include <linux/err.h>
15 #include <linux/slab.h>
16 #include <linux/string.h>
17 #include <linux/mm.h>
18 #include <linux/mmzone.h>
19 #include <linux/memory.h>
20 #include <linux/platform_device.h>
21 #include <asm/chpid.h>
22 #include <asm/sclp.h>
23 #include <asm/setup.h>
24
25 #include "sclp.h"
26
27 #define SCLP_CMDW_READ_SCP_INFO 0x00020001
28 #define SCLP_CMDW_READ_SCP_INFO_FORCED 0x00120001
29
30 struct read_info_sccb {
31 struct sccb_header header; /* 0-7 */
32 u16 rnmax; /* 8-9 */
33 u8 rnsize; /* 10 */
34 u8 _reserved0[24 - 11]; /* 11-15 */
35 u8 loadparm[8]; /* 24-31 */
36 u8 _reserved1[48 - 32]; /* 32-47 */
37 u64 facilities; /* 48-55 */
38 u8 _reserved2[84 - 56]; /* 56-83 */
39 u8 fac84; /* 84 */
40 u8 _reserved3[91 - 85]; /* 85-90 */
41 u8 flags; /* 91 */
42 u8 _reserved4[100 - 92]; /* 92-99 */
43 u32 rnsize2; /* 100-103 */
44 u64 rnmax2; /* 104-111 */
45 u8 _reserved5[4096 - 112]; /* 112-4095 */
46 } __attribute__((packed, aligned(PAGE_SIZE)));
47
48 static struct read_info_sccb __initdata early_read_info_sccb;
49 static int __initdata early_read_info_sccb_valid;
50
51 u64 sclp_facilities;
52 static u8 sclp_fac84;
53 static unsigned long long rzm;
54 static unsigned long long rnmax;
55
56 static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
57 {
58 int rc;
59
60 __ctl_set_bit(0, 9);
61 rc = sclp_service_call(cmd, sccb);
62 if (rc)
63 goto out;
64 __load_psw_mask(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA |
65 PSW_MASK_BA | PSW_MASK_EXT | PSW_MASK_WAIT);
66 local_irq_disable();
67 out:
68 /* Contents of the sccb might have changed. */
69 barrier();
70 __ctl_clear_bit(0, 9);
71 return rc;
72 }
73
74 static void __init sclp_read_info_early(void)
75 {
76 int rc;
77 int i;
78 struct read_info_sccb *sccb;
79 sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
80 SCLP_CMDW_READ_SCP_INFO};
81
82 sccb = &early_read_info_sccb;
83 for (i = 0; i < ARRAY_SIZE(commands); i++) {
84 do {
85 memset(sccb, 0, sizeof(*sccb));
86 sccb->header.length = sizeof(*sccb);
87 sccb->header.function_code = 0x80;
88 sccb->header.control_mask[2] = 0x80;
89 rc = sclp_cmd_sync_early(commands[i], sccb);
90 } while (rc == -EBUSY);
91
92 if (rc)
93 break;
94 if (sccb->header.response_code == 0x10) {
95 early_read_info_sccb_valid = 1;
96 break;
97 }
98 if (sccb->header.response_code != 0x1f0)
99 break;
100 }
101 }
102
103 void __init sclp_facilities_detect(void)
104 {
105 struct read_info_sccb *sccb;
106
107 sclp_read_info_early();
108 if (!early_read_info_sccb_valid)
109 return;
110
111 sccb = &early_read_info_sccb;
112 sclp_facilities = sccb->facilities;
113 sclp_fac84 = sccb->fac84;
114 rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
115 rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
116 rzm <<= 20;
117 }
118
119 unsigned long long sclp_get_rnmax(void)
120 {
121 return rnmax;
122 }
123
124 unsigned long long sclp_get_rzm(void)
125 {
126 return rzm;
127 }
128
129 /*
130 * This function will be called after sclp_facilities_detect(), which gets
131 * called from early.c code. Therefore the sccb should have valid contents.
132 */
133 void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
134 {
135 struct read_info_sccb *sccb;
136
137 if (!early_read_info_sccb_valid)
138 return;
139 sccb = &early_read_info_sccb;
140 info->is_valid = 1;
141 if (sccb->flags & 0x2)
142 info->has_dump = 1;
143 memcpy(&info->loadparm, &sccb->loadparm, LOADPARM_LEN);
144 }
145
146 static void sclp_sync_callback(struct sclp_req *req, void *data)
147 {
148 struct completion *completion = data;
149
150 complete(completion);
151 }
152
153 static int do_sync_request(sclp_cmdw_t cmd, void *sccb)
154 {
155 struct completion completion;
156 struct sclp_req *request;
157 int rc;
158
159 request = kzalloc(sizeof(*request), GFP_KERNEL);
160 if (!request)
161 return -ENOMEM;
162 request->command = cmd;
163 request->sccb = sccb;
164 request->status = SCLP_REQ_FILLED;
165 request->callback = sclp_sync_callback;
166 request->callback_data = &completion;
167 init_completion(&completion);
168
169 /* Perform sclp request. */
170 rc = sclp_add_request(request);
171 if (rc)
172 goto out;
173 wait_for_completion(&completion);
174
175 /* Check response. */
176 if (request->status != SCLP_REQ_DONE) {
177 pr_warning("sync request failed (cmd=0x%08x, "
178 "status=0x%02x)\n", cmd, request->status);
179 rc = -EIO;
180 }
181 out:
182 kfree(request);
183 return rc;
184 }
185
186 /*
187 * CPU configuration related functions.
188 */
189
190 #define SCLP_CMDW_READ_CPU_INFO 0x00010001
191 #define SCLP_CMDW_CONFIGURE_CPU 0x00110001
192 #define SCLP_CMDW_DECONFIGURE_CPU 0x00100001
193
194 struct read_cpu_info_sccb {
195 struct sccb_header header;
196 u16 nr_configured;
197 u16 offset_configured;
198 u16 nr_standby;
199 u16 offset_standby;
200 u8 reserved[4096 - 16];
201 } __attribute__((packed, aligned(PAGE_SIZE)));
202
203 static void sclp_fill_cpu_info(struct sclp_cpu_info *info,
204 struct read_cpu_info_sccb *sccb)
205 {
206 char *page = (char *) sccb;
207
208 memset(info, 0, sizeof(*info));
209 info->configured = sccb->nr_configured;
210 info->standby = sccb->nr_standby;
211 info->combined = sccb->nr_configured + sccb->nr_standby;
212 info->has_cpu_type = sclp_fac84 & 0x1;
213 memcpy(&info->cpu, page + sccb->offset_configured,
214 info->combined * sizeof(struct sclp_cpu_entry));
215 }
216
217 int sclp_get_cpu_info(struct sclp_cpu_info *info)
218 {
219 int rc;
220 struct read_cpu_info_sccb *sccb;
221
222 if (!SCLP_HAS_CPU_INFO)
223 return -EOPNOTSUPP;
224 sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
225 if (!sccb)
226 return -ENOMEM;
227 sccb->header.length = sizeof(*sccb);
228 rc = do_sync_request(SCLP_CMDW_READ_CPU_INFO, sccb);
229 if (rc)
230 goto out;
231 if (sccb->header.response_code != 0x0010) {
232 pr_warning("readcpuinfo failed (response=0x%04x)\n",
233 sccb->header.response_code);
234 rc = -EIO;
235 goto out;
236 }
237 sclp_fill_cpu_info(info, sccb);
238 out:
239 free_page((unsigned long) sccb);
240 return rc;
241 }
242
243 struct cpu_configure_sccb {
244 struct sccb_header header;
245 } __attribute__((packed, aligned(8)));
246
247 static int do_cpu_configure(sclp_cmdw_t cmd)
248 {
249 struct cpu_configure_sccb *sccb;
250 int rc;
251
252 if (!SCLP_HAS_CPU_RECONFIG)
253 return -EOPNOTSUPP;
254 /*
255 * This is not going to cross a page boundary since we force
256 * kmalloc to have a minimum alignment of 8 bytes on s390.
257 */
258 sccb = kzalloc(sizeof(*sccb), GFP_KERNEL | GFP_DMA);
259 if (!sccb)
260 return -ENOMEM;
261 sccb->header.length = sizeof(*sccb);
262 rc = do_sync_request(cmd, sccb);
263 if (rc)
264 goto out;
265 switch (sccb->header.response_code) {
266 case 0x0020:
267 case 0x0120:
268 break;
269 default:
270 pr_warning("configure cpu failed (cmd=0x%08x, "
271 "response=0x%04x)\n", cmd,
272 sccb->header.response_code);
273 rc = -EIO;
274 break;
275 }
276 out:
277 kfree(sccb);
278 return rc;
279 }
280
281 int sclp_cpu_configure(u8 cpu)
282 {
283 return do_cpu_configure(SCLP_CMDW_CONFIGURE_CPU | cpu << 8);
284 }
285
286 int sclp_cpu_deconfigure(u8 cpu)
287 {
288 return do_cpu_configure(SCLP_CMDW_DECONFIGURE_CPU | cpu << 8);
289 }
290
291 #ifdef CONFIG_MEMORY_HOTPLUG
292
293 static DEFINE_MUTEX(sclp_mem_mutex);
294 static LIST_HEAD(sclp_mem_list);
295 static u8 sclp_max_storage_id;
296 static unsigned long sclp_storage_ids[256 / BITS_PER_LONG];
297 static int sclp_mem_state_changed;
298
299 struct memory_increment {
300 struct list_head list;
301 u16 rn;
302 int standby;
303 int usecount;
304 };
305
306 struct assign_storage_sccb {
307 struct sccb_header header;
308 u16 rn;
309 } __packed;
310
311 int arch_get_memory_phys_device(unsigned long start_pfn)
312 {
313 if (!rzm)
314 return 0;
315 return PFN_PHYS(start_pfn) >> ilog2(rzm);
316 }
317
318 static unsigned long long rn2addr(u16 rn)
319 {
320 return (unsigned long long) (rn - 1) * rzm;
321 }
322
323 static int do_assign_storage(sclp_cmdw_t cmd, u16 rn)
324 {
325 struct assign_storage_sccb *sccb;
326 int rc;
327
328 sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
329 if (!sccb)
330 return -ENOMEM;
331 sccb->header.length = PAGE_SIZE;
332 sccb->rn = rn;
333 rc = do_sync_request(cmd, sccb);
334 if (rc)
335 goto out;
336 switch (sccb->header.response_code) {
337 case 0x0020:
338 case 0x0120:
339 break;
340 default:
341 pr_warning("assign storage failed (cmd=0x%08x, "
342 "response=0x%04x, rn=0x%04x)\n", cmd,
343 sccb->header.response_code, rn);
344 rc = -EIO;
345 break;
346 }
347 out:
348 free_page((unsigned long) sccb);
349 return rc;
350 }
351
352 static int sclp_assign_storage(u16 rn)
353 {
354 return do_assign_storage(0x000d0001, rn);
355 }
356
357 static int sclp_unassign_storage(u16 rn)
358 {
359 return do_assign_storage(0x000c0001, rn);
360 }
361
362 struct attach_storage_sccb {
363 struct sccb_header header;
364 u16 :16;
365 u16 assigned;
366 u32 :32;
367 u32 entries[0];
368 } __packed;
369
370 static int sclp_attach_storage(u8 id)
371 {
372 struct attach_storage_sccb *sccb;
373 int rc;
374 int i;
375
376 sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
377 if (!sccb)
378 return -ENOMEM;
379 sccb->header.length = PAGE_SIZE;
380 rc = do_sync_request(0x00080001 | id << 8, sccb);
381 if (rc)
382 goto out;
383 switch (sccb->header.response_code) {
384 case 0x0020:
385 set_bit(id, sclp_storage_ids);
386 for (i = 0; i < sccb->assigned; i++) {
387 if (sccb->entries[i])
388 sclp_unassign_storage(sccb->entries[i] >> 16);
389 }
390 break;
391 default:
392 rc = -EIO;
393 break;
394 }
395 out:
396 free_page((unsigned long) sccb);
397 return rc;
398 }
399
400 static int sclp_mem_change_state(unsigned long start, unsigned long size,
401 int online)
402 {
403 struct memory_increment *incr;
404 unsigned long long istart;
405 int rc = 0;
406
407 list_for_each_entry(incr, &sclp_mem_list, list) {
408 istart = rn2addr(incr->rn);
409 if (start + size - 1 < istart)
410 break;
411 if (start > istart + rzm - 1)
412 continue;
413 if (online) {
414 if (incr->usecount++)
415 continue;
416 /*
417 * Don't break the loop if one assign fails. Loop may
418 * be walked again on CANCEL and we can't save
419 * information if state changed before or not.
420 * So continue and increase usecount for all increments.
421 */
422 rc |= sclp_assign_storage(incr->rn);
423 } else {
424 if (--incr->usecount)
425 continue;
426 sclp_unassign_storage(incr->rn);
427 }
428 }
429 return rc ? -EIO : 0;
430 }
431
432 static int sclp_mem_notifier(struct notifier_block *nb,
433 unsigned long action, void *data)
434 {
435 unsigned long start, size;
436 struct memory_notify *arg;
437 unsigned char id;
438 int rc = 0;
439
440 arg = data;
441 start = arg->start_pfn << PAGE_SHIFT;
442 size = arg->nr_pages << PAGE_SHIFT;
443 mutex_lock(&sclp_mem_mutex);
444 for (id = 0; id <= sclp_max_storage_id; id++)
445 if (!test_bit(id, sclp_storage_ids))
446 sclp_attach_storage(id);
447 switch (action) {
448 case MEM_ONLINE:
449 case MEM_GOING_OFFLINE:
450 case MEM_CANCEL_OFFLINE:
451 break;
452 case MEM_GOING_ONLINE:
453 rc = sclp_mem_change_state(start, size, 1);
454 break;
455 case MEM_CANCEL_ONLINE:
456 sclp_mem_change_state(start, size, 0);
457 break;
458 case MEM_OFFLINE:
459 sclp_mem_change_state(start, size, 0);
460 break;
461 default:
462 rc = -EINVAL;
463 break;
464 }
465 if (!rc)
466 sclp_mem_state_changed = 1;
467 mutex_unlock(&sclp_mem_mutex);
468 return rc ? NOTIFY_BAD : NOTIFY_OK;
469 }
470
471 static struct notifier_block sclp_mem_nb = {
472 .notifier_call = sclp_mem_notifier,
473 };
474
475 static void __init add_memory_merged(u16 rn)
476 {
477 static u16 first_rn, num;
478 unsigned long long start, size;
479
480 if (rn && first_rn && (first_rn + num == rn)) {
481 num++;
482 return;
483 }
484 if (!first_rn)
485 goto skip_add;
486 start = rn2addr(first_rn);
487 size = (unsigned long long ) num * rzm;
488 if (start >= VMEM_MAX_PHYS)
489 goto skip_add;
490 if (start + size > VMEM_MAX_PHYS)
491 size = VMEM_MAX_PHYS - start;
492 if (memory_end_set && (start >= memory_end))
493 goto skip_add;
494 if (memory_end_set && (start + size > memory_end))
495 size = memory_end - start;
496 add_memory(0, start, size);
497 skip_add:
498 first_rn = rn;
499 num = 1;
500 }
501
502 static void __init sclp_add_standby_memory(void)
503 {
504 struct memory_increment *incr;
505
506 list_for_each_entry(incr, &sclp_mem_list, list)
507 if (incr->standby)
508 add_memory_merged(incr->rn);
509 add_memory_merged(0);
510 }
511
512 static void __init insert_increment(u16 rn, int standby, int assigned)
513 {
514 struct memory_increment *incr, *new_incr;
515 struct list_head *prev;
516 u16 last_rn;
517
518 new_incr = kzalloc(sizeof(*new_incr), GFP_KERNEL);
519 if (!new_incr)
520 return;
521 new_incr->rn = rn;
522 new_incr->standby = standby;
523 if (!standby)
524 new_incr->usecount = 1;
525 last_rn = 0;
526 prev = &sclp_mem_list;
527 list_for_each_entry(incr, &sclp_mem_list, list) {
528 if (assigned && incr->rn > rn)
529 break;
530 if (!assigned && incr->rn - last_rn > 1)
531 break;
532 last_rn = incr->rn;
533 prev = &incr->list;
534 }
535 if (!assigned)
536 new_incr->rn = last_rn + 1;
537 if (new_incr->rn > rnmax) {
538 kfree(new_incr);
539 return;
540 }
541 list_add(&new_incr->list, prev);
542 }
543
544 static int sclp_mem_freeze(struct device *dev)
545 {
546 if (!sclp_mem_state_changed)
547 return 0;
548 pr_err("Memory hotplug state changed, suspend refused.\n");
549 return -EPERM;
550 }
551
552 struct read_storage_sccb {
553 struct sccb_header header;
554 u16 max_id;
555 u16 assigned;
556 u16 standby;
557 u16 :16;
558 u32 entries[0];
559 } __packed;
560
561 static const struct dev_pm_ops sclp_mem_pm_ops = {
562 .freeze = sclp_mem_freeze,
563 };
564
565 static struct platform_driver sclp_mem_pdrv = {
566 .driver = {
567 .name = "sclp_mem",
568 .pm = &sclp_mem_pm_ops,
569 },
570 };
571
572 static int __init sclp_detect_standby_memory(void)
573 {
574 struct platform_device *sclp_pdev;
575 struct read_storage_sccb *sccb;
576 int i, id, assigned, rc;
577
578 if (!early_read_info_sccb_valid)
579 return 0;
580 if ((sclp_facilities & 0xe00000000000ULL) != 0xe00000000000ULL)
581 return 0;
582 rc = -ENOMEM;
583 sccb = (void *) __get_free_page(GFP_KERNEL | GFP_DMA);
584 if (!sccb)
585 goto out;
586 assigned = 0;
587 for (id = 0; id <= sclp_max_storage_id; id++) {
588 memset(sccb, 0, PAGE_SIZE);
589 sccb->header.length = PAGE_SIZE;
590 rc = do_sync_request(0x00040001 | id << 8, sccb);
591 if (rc)
592 goto out;
593 switch (sccb->header.response_code) {
594 case 0x0010:
595 set_bit(id, sclp_storage_ids);
596 for (i = 0; i < sccb->assigned; i++) {
597 if (!sccb->entries[i])
598 continue;
599 assigned++;
600 insert_increment(sccb->entries[i] >> 16, 0, 1);
601 }
602 break;
603 case 0x0310:
604 break;
605 case 0x0410:
606 for (i = 0; i < sccb->assigned; i++) {
607 if (!sccb->entries[i])
608 continue;
609 assigned++;
610 insert_increment(sccb->entries[i] >> 16, 1, 1);
611 }
612 break;
613 default:
614 rc = -EIO;
615 break;
616 }
617 if (!rc)
618 sclp_max_storage_id = sccb->max_id;
619 }
620 if (rc || list_empty(&sclp_mem_list))
621 goto out;
622 for (i = 1; i <= rnmax - assigned; i++)
623 insert_increment(0, 1, 0);
624 rc = register_memory_notifier(&sclp_mem_nb);
625 if (rc)
626 goto out;
627 rc = platform_driver_register(&sclp_mem_pdrv);
628 if (rc)
629 goto out;
630 sclp_pdev = platform_device_register_simple("sclp_mem", -1, NULL, 0);
631 rc = IS_ERR(sclp_pdev) ? PTR_ERR(sclp_pdev) : 0;
632 if (rc)
633 goto out_driver;
634 sclp_add_standby_memory();
635 goto out;
636 out_driver:
637 platform_driver_unregister(&sclp_mem_pdrv);
638 out:
639 free_page((unsigned long) sccb);
640 return rc;
641 }
642 __initcall(sclp_detect_standby_memory);
643
644 #endif /* CONFIG_MEMORY_HOTPLUG */
645
646 /*
647 * Channel path configuration related functions.
648 */
649
650 #define SCLP_CMDW_CONFIGURE_CHPATH 0x000f0001
651 #define SCLP_CMDW_DECONFIGURE_CHPATH 0x000e0001
652 #define SCLP_CMDW_READ_CHPATH_INFORMATION 0x00030001
653
654 struct chp_cfg_sccb {
655 struct sccb_header header;
656 u8 ccm;
657 u8 reserved[6];
658 u8 cssid;
659 } __attribute__((packed));
660
661 static int do_chp_configure(sclp_cmdw_t cmd)
662 {
663 struct chp_cfg_sccb *sccb;
664 int rc;
665
666 if (!SCLP_HAS_CHP_RECONFIG)
667 return -EOPNOTSUPP;
668 /* Prepare sccb. */
669 sccb = (struct chp_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
670 if (!sccb)
671 return -ENOMEM;
672 sccb->header.length = sizeof(*sccb);
673 rc = do_sync_request(cmd, sccb);
674 if (rc)
675 goto out;
676 switch (sccb->header.response_code) {
677 case 0x0020:
678 case 0x0120:
679 case 0x0440:
680 case 0x0450:
681 break;
682 default:
683 pr_warning("configure channel-path failed "
684 "(cmd=0x%08x, response=0x%04x)\n", cmd,
685 sccb->header.response_code);
686 rc = -EIO;
687 break;
688 }
689 out:
690 free_page((unsigned long) sccb);
691 return rc;
692 }
693
694 /**
695 * sclp_chp_configure - perform configure channel-path sclp command
696 * @chpid: channel-path ID
697 *
698 * Perform configure channel-path command sclp command for specified chpid.
699 * Return 0 after command successfully finished, non-zero otherwise.
700 */
701 int sclp_chp_configure(struct chp_id chpid)
702 {
703 return do_chp_configure(SCLP_CMDW_CONFIGURE_CHPATH | chpid.id << 8);
704 }
705
706 /**
707 * sclp_chp_deconfigure - perform deconfigure channel-path sclp command
708 * @chpid: channel-path ID
709 *
710 * Perform deconfigure channel-path command sclp command for specified chpid
711 * and wait for completion. On success return 0. Return non-zero otherwise.
712 */
713 int sclp_chp_deconfigure(struct chp_id chpid)
714 {
715 return do_chp_configure(SCLP_CMDW_DECONFIGURE_CHPATH | chpid.id << 8);
716 }
717
718 struct chp_info_sccb {
719 struct sccb_header header;
720 u8 recognized[SCLP_CHP_INFO_MASK_SIZE];
721 u8 standby[SCLP_CHP_INFO_MASK_SIZE];
722 u8 configured[SCLP_CHP_INFO_MASK_SIZE];
723 u8 ccm;
724 u8 reserved[6];
725 u8 cssid;
726 } __attribute__((packed));
727
728 /**
729 * sclp_chp_read_info - perform read channel-path information sclp command
730 * @info: resulting channel-path information data
731 *
732 * Perform read channel-path information sclp command and wait for completion.
733 * On success, store channel-path information in @info and return 0. Return
734 * non-zero otherwise.
735 */
736 int sclp_chp_read_info(struct sclp_chp_info *info)
737 {
738 struct chp_info_sccb *sccb;
739 int rc;
740
741 if (!SCLP_HAS_CHP_INFO)
742 return -EOPNOTSUPP;
743 /* Prepare sccb. */
744 sccb = (struct chp_info_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
745 if (!sccb)
746 return -ENOMEM;
747 sccb->header.length = sizeof(*sccb);
748 rc = do_sync_request(SCLP_CMDW_READ_CHPATH_INFORMATION, sccb);
749 if (rc)
750 goto out;
751 if (sccb->header.response_code != 0x0010) {
752 pr_warning("read channel-path info failed "
753 "(response=0x%04x)\n", sccb->header.response_code);
754 rc = -EIO;
755 goto out;
756 }
757 memcpy(info->recognized, sccb->recognized, SCLP_CHP_INFO_MASK_SIZE);
758 memcpy(info->standby, sccb->standby, SCLP_CHP_INFO_MASK_SIZE);
759 memcpy(info->configured, sccb->configured, SCLP_CHP_INFO_MASK_SIZE);
760 out:
761 free_page((unsigned long) sccb);
762 return rc;
763 }