Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / s390 / char / sclp_cmd.c
1 /*
2  * Copyright IBM Corp. 2007,2012
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/export.h>
16 #include <linux/slab.h>
17 #include <linux/string.h>
18 #include <linux/mm.h>
19 #include <linux/mmzone.h>
20 #include <linux/memory.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <asm/ctl_reg.h>
24 #include <asm/chpid.h>
25 #include <asm/setup.h>
26 #include <asm/page.h>
27 #include <asm/sclp.h>
28
29 #include "sclp.h"
30
31 static void sclp_sync_callback(struct sclp_req *req, void *data)
32 {
33         struct completion *completion = data;
34
35         complete(completion);
36 }
37
38 int sclp_sync_request(sclp_cmdw_t cmd, void *sccb)
39 {
40         return sclp_sync_request_timeout(cmd, sccb, 0);
41 }
42
43 int sclp_sync_request_timeout(sclp_cmdw_t cmd, void *sccb, int timeout)
44 {
45         struct completion completion;
46         struct sclp_req *request;
47         int rc;
48
49         request = kzalloc(sizeof(*request), GFP_KERNEL);
50         if (!request)
51                 return -ENOMEM;
52         if (timeout)
53                 request->queue_timeout = timeout;
54         request->command = cmd;
55         request->sccb = sccb;
56         request->status = SCLP_REQ_FILLED;
57         request->callback = sclp_sync_callback;
58         request->callback_data = &completion;
59         init_completion(&completion);
60
61         /* Perform sclp request. */
62         rc = sclp_add_request(request);
63         if (rc)
64                 goto out;
65         wait_for_completion(&completion);
66
67         /* Check response. */
68         if (request->status != SCLP_REQ_DONE) {
69                 pr_warning("sync request failed (cmd=0x%08x, "
70                            "status=0x%02x)\n", cmd, request->status);
71                 rc = -EIO;
72         }
73 out:
74         kfree(request);
75         return rc;
76 }
77
78 /*
79  * CPU configuration related functions.
80  */
81
82 #define SCLP_CMDW_READ_CPU_INFO         0x00010001
83 #define SCLP_CMDW_CONFIGURE_CPU         0x00110001
84 #define SCLP_CMDW_DECONFIGURE_CPU       0x00100001
85
86 struct read_cpu_info_sccb {
87         struct  sccb_header header;
88         u16     nr_configured;
89         u16     offset_configured;
90         u16     nr_standby;
91         u16     offset_standby;
92         u8      reserved[4096 - 16];
93 } __attribute__((packed, aligned(PAGE_SIZE)));
94
95 static void sclp_fill_cpu_info(struct sclp_cpu_info *info,
96                                struct read_cpu_info_sccb *sccb)
97 {
98         char *page = (char *) sccb;
99
100         memset(info, 0, sizeof(*info));
101         info->configured = sccb->nr_configured;
102         info->standby = sccb->nr_standby;
103         info->combined = sccb->nr_configured + sccb->nr_standby;
104         info->has_cpu_type = sclp_fac84 & 0x1;
105         memcpy(&info->cpu, page + sccb->offset_configured,
106                info->combined * sizeof(struct sclp_cpu_entry));
107 }
108
109 int sclp_get_cpu_info(struct sclp_cpu_info *info)
110 {
111         int rc;
112         struct read_cpu_info_sccb *sccb;
113
114         if (!SCLP_HAS_CPU_INFO)
115                 return -EOPNOTSUPP;
116         sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
117         if (!sccb)
118                 return -ENOMEM;
119         sccb->header.length = sizeof(*sccb);
120         rc = sclp_sync_request_timeout(SCLP_CMDW_READ_CPU_INFO, sccb,
121                                        SCLP_QUEUE_INTERVAL);
122         if (rc)
123                 goto out;
124         if (sccb->header.response_code != 0x0010) {
125                 pr_warning("readcpuinfo failed (response=0x%04x)\n",
126                            sccb->header.response_code);
127                 rc = -EIO;
128                 goto out;
129         }
130         sclp_fill_cpu_info(info, sccb);
131 out:
132         free_page((unsigned long) sccb);
133         return rc;
134 }
135
136 struct cpu_configure_sccb {
137         struct sccb_header header;
138 } __attribute__((packed, aligned(8)));
139
140 static int do_cpu_configure(sclp_cmdw_t cmd)
141 {
142         struct cpu_configure_sccb *sccb;
143         int rc;
144
145         if (!SCLP_HAS_CPU_RECONFIG)
146                 return -EOPNOTSUPP;
147         /*
148          * This is not going to cross a page boundary since we force
149          * kmalloc to have a minimum alignment of 8 bytes on s390.
150          */
151         sccb = kzalloc(sizeof(*sccb), GFP_KERNEL | GFP_DMA);
152         if (!sccb)
153                 return -ENOMEM;
154         sccb->header.length = sizeof(*sccb);
155         rc = sclp_sync_request_timeout(cmd, sccb, SCLP_QUEUE_INTERVAL);
156         if (rc)
157                 goto out;
158         switch (sccb->header.response_code) {
159         case 0x0020:
160         case 0x0120:
161                 break;
162         default:
163                 pr_warning("configure cpu failed (cmd=0x%08x, "
164                            "response=0x%04x)\n", cmd,
165                            sccb->header.response_code);
166                 rc = -EIO;
167                 break;
168         }
169 out:
170         kfree(sccb);
171         return rc;
172 }
173
174 int sclp_cpu_configure(u8 cpu)
175 {
176         return do_cpu_configure(SCLP_CMDW_CONFIGURE_CPU | cpu << 8);
177 }
178
179 int sclp_cpu_deconfigure(u8 cpu)
180 {
181         return do_cpu_configure(SCLP_CMDW_DECONFIGURE_CPU | cpu << 8);
182 }
183
184 #ifdef CONFIG_MEMORY_HOTPLUG
185
186 static DEFINE_MUTEX(sclp_mem_mutex);
187 static LIST_HEAD(sclp_mem_list);
188 static u8 sclp_max_storage_id;
189 static unsigned long sclp_storage_ids[256 / BITS_PER_LONG];
190 static int sclp_mem_state_changed;
191
192 struct memory_increment {
193         struct list_head list;
194         u16 rn;
195         int standby;
196 };
197
198 struct assign_storage_sccb {
199         struct sccb_header header;
200         u16 rn;
201 } __packed;
202
203 int arch_get_memory_phys_device(unsigned long start_pfn)
204 {
205         if (!sclp_rzm)
206                 return 0;
207         return PFN_PHYS(start_pfn) >> ilog2(sclp_rzm);
208 }
209
210 static unsigned long long rn2addr(u16 rn)
211 {
212         return (unsigned long long) (rn - 1) * sclp_rzm;
213 }
214
215 static int do_assign_storage(sclp_cmdw_t cmd, u16 rn)
216 {
217         struct assign_storage_sccb *sccb;
218         int rc;
219
220         sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
221         if (!sccb)
222                 return -ENOMEM;
223         sccb->header.length = PAGE_SIZE;
224         sccb->rn = rn;
225         rc = sclp_sync_request_timeout(cmd, sccb, SCLP_QUEUE_INTERVAL);
226         if (rc)
227                 goto out;
228         switch (sccb->header.response_code) {
229         case 0x0020:
230         case 0x0120:
231                 break;
232         default:
233                 pr_warning("assign storage failed (cmd=0x%08x, "
234                            "response=0x%04x, rn=0x%04x)\n", cmd,
235                            sccb->header.response_code, rn);
236                 rc = -EIO;
237                 break;
238         }
239 out:
240         free_page((unsigned long) sccb);
241         return rc;
242 }
243
244 static int sclp_assign_storage(u16 rn)
245 {
246         unsigned long long start;
247         int rc;
248
249         rc = do_assign_storage(0x000d0001, rn);
250         if (rc)
251                 return rc;
252         start = rn2addr(rn);
253         storage_key_init_range(start, start + sclp_rzm);
254         return 0;
255 }
256
257 static int sclp_unassign_storage(u16 rn)
258 {
259         return do_assign_storage(0x000c0001, rn);
260 }
261
262 struct attach_storage_sccb {
263         struct sccb_header header;
264         u16 :16;
265         u16 assigned;
266         u32 :32;
267         u32 entries[0];
268 } __packed;
269
270 static int sclp_attach_storage(u8 id)
271 {
272         struct attach_storage_sccb *sccb;
273         int rc;
274         int i;
275
276         sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
277         if (!sccb)
278                 return -ENOMEM;
279         sccb->header.length = PAGE_SIZE;
280         rc = sclp_sync_request_timeout(0x00080001 | id << 8, sccb,
281                                        SCLP_QUEUE_INTERVAL);
282         if (rc)
283                 goto out;
284         switch (sccb->header.response_code) {
285         case 0x0020:
286                 set_bit(id, sclp_storage_ids);
287                 for (i = 0; i < sccb->assigned; i++) {
288                         if (sccb->entries[i])
289                                 sclp_unassign_storage(sccb->entries[i] >> 16);
290                 }
291                 break;
292         default:
293                 rc = -EIO;
294                 break;
295         }
296 out:
297         free_page((unsigned long) sccb);
298         return rc;
299 }
300
301 static int sclp_mem_change_state(unsigned long start, unsigned long size,
302                                  int online)
303 {
304         struct memory_increment *incr;
305         unsigned long long istart;
306         int rc = 0;
307
308         list_for_each_entry(incr, &sclp_mem_list, list) {
309                 istart = rn2addr(incr->rn);
310                 if (start + size - 1 < istart)
311                         break;
312                 if (start > istart + sclp_rzm - 1)
313                         continue;
314                 if (online)
315                         rc |= sclp_assign_storage(incr->rn);
316                 else
317                         sclp_unassign_storage(incr->rn);
318                 if (rc == 0)
319                         incr->standby = online ? 0 : 1;
320         }
321         return rc ? -EIO : 0;
322 }
323
324 static bool contains_standby_increment(unsigned long start, unsigned long end)
325 {
326         struct memory_increment *incr;
327         unsigned long istart;
328
329         list_for_each_entry(incr, &sclp_mem_list, list) {
330                 istart = rn2addr(incr->rn);
331                 if (end - 1 < istart)
332                         continue;
333                 if (start > istart + sclp_rzm - 1)
334                         continue;
335                 if (incr->standby)
336                         return true;
337         }
338         return false;
339 }
340
341 static int sclp_mem_notifier(struct notifier_block *nb,
342                              unsigned long action, void *data)
343 {
344         unsigned long start, size;
345         struct memory_notify *arg;
346         unsigned char id;
347         int rc = 0;
348
349         arg = data;
350         start = arg->start_pfn << PAGE_SHIFT;
351         size = arg->nr_pages << PAGE_SHIFT;
352         mutex_lock(&sclp_mem_mutex);
353         for_each_clear_bit(id, sclp_storage_ids, sclp_max_storage_id + 1)
354                 sclp_attach_storage(id);
355         switch (action) {
356         case MEM_GOING_OFFLINE:
357                 /*
358                  * We do not allow to set memory blocks offline that contain
359                  * standby memory. This is done to simplify the "memory online"
360                  * case.
361                  */
362                 if (contains_standby_increment(start, start + size))
363                         rc = -EPERM;
364                 break;
365         case MEM_ONLINE:
366         case MEM_CANCEL_OFFLINE:
367                 break;
368         case MEM_GOING_ONLINE:
369                 rc = sclp_mem_change_state(start, size, 1);
370                 break;
371         case MEM_CANCEL_ONLINE:
372                 sclp_mem_change_state(start, size, 0);
373                 break;
374         case MEM_OFFLINE:
375                 sclp_mem_change_state(start, size, 0);
376                 break;
377         default:
378                 rc = -EINVAL;
379                 break;
380         }
381         if (!rc)
382                 sclp_mem_state_changed = 1;
383         mutex_unlock(&sclp_mem_mutex);
384         return rc ? NOTIFY_BAD : NOTIFY_OK;
385 }
386
387 static struct notifier_block sclp_mem_nb = {
388         .notifier_call = sclp_mem_notifier,
389 };
390
391 static void __init align_to_block_size(unsigned long long *start,
392                                        unsigned long long *size)
393 {
394         unsigned long long start_align, size_align, alignment;
395
396         alignment = memory_block_size_bytes();
397         start_align = roundup(*start, alignment);
398         size_align = rounddown(*start + *size, alignment) - start_align;
399
400         pr_info("Standby memory at 0x%llx (%lluM of %lluM usable)\n",
401                 *start, size_align >> 20, *size >> 20);
402         *start = start_align;
403         *size = size_align;
404 }
405
406 static void __init add_memory_merged(u16 rn)
407 {
408         static u16 first_rn, num;
409         unsigned long long start, size;
410
411         if (rn && first_rn && (first_rn + num == rn)) {
412                 num++;
413                 return;
414         }
415         if (!first_rn)
416                 goto skip_add;
417         start = rn2addr(first_rn);
418         size = (unsigned long long) num * sclp_rzm;
419         if (start >= VMEM_MAX_PHYS)
420                 goto skip_add;
421         if (start + size > VMEM_MAX_PHYS)
422                 size = VMEM_MAX_PHYS - start;
423         if (memory_end_set && (start >= memory_end))
424                 goto skip_add;
425         if (memory_end_set && (start + size > memory_end))
426                 size = memory_end - start;
427         align_to_block_size(&start, &size);
428         if (size)
429                 add_memory(0, start, size);
430 skip_add:
431         first_rn = rn;
432         num = 1;
433 }
434
435 static void __init sclp_add_standby_memory(void)
436 {
437         struct memory_increment *incr;
438
439         list_for_each_entry(incr, &sclp_mem_list, list)
440                 if (incr->standby)
441                         add_memory_merged(incr->rn);
442         add_memory_merged(0);
443 }
444
445 static void __init insert_increment(u16 rn, int standby, int assigned)
446 {
447         struct memory_increment *incr, *new_incr;
448         struct list_head *prev;
449         u16 last_rn;
450
451         new_incr = kzalloc(sizeof(*new_incr), GFP_KERNEL);
452         if (!new_incr)
453                 return;
454         new_incr->rn = rn;
455         new_incr->standby = standby;
456         last_rn = 0;
457         prev = &sclp_mem_list;
458         list_for_each_entry(incr, &sclp_mem_list, list) {
459                 if (assigned && incr->rn > rn)
460                         break;
461                 if (!assigned && incr->rn - last_rn > 1)
462                         break;
463                 last_rn = incr->rn;
464                 prev = &incr->list;
465         }
466         if (!assigned)
467                 new_incr->rn = last_rn + 1;
468         if (new_incr->rn > sclp_rnmax) {
469                 kfree(new_incr);
470                 return;
471         }
472         list_add(&new_incr->list, prev);
473 }
474
475 static int sclp_mem_freeze(struct device *dev)
476 {
477         if (!sclp_mem_state_changed)
478                 return 0;
479         pr_err("Memory hotplug state changed, suspend refused.\n");
480         return -EPERM;
481 }
482
483 struct read_storage_sccb {
484         struct sccb_header header;
485         u16 max_id;
486         u16 assigned;
487         u16 standby;
488         u16 :16;
489         u32 entries[0];
490 } __packed;
491
492 static const struct dev_pm_ops sclp_mem_pm_ops = {
493         .freeze         = sclp_mem_freeze,
494 };
495
496 static struct platform_driver sclp_mem_pdrv = {
497         .driver = {
498                 .name   = "sclp_mem",
499                 .pm     = &sclp_mem_pm_ops,
500         },
501 };
502
503 static int __init sclp_detect_standby_memory(void)
504 {
505         struct platform_device *sclp_pdev;
506         struct read_storage_sccb *sccb;
507         int i, id, assigned, rc;
508
509         if (OLDMEM_BASE) /* No standby memory in kdump mode */
510                 return 0;
511         if ((sclp_facilities & 0xe00000000000ULL) != 0xe00000000000ULL)
512                 return 0;
513         rc = -ENOMEM;
514         sccb = (void *) __get_free_page(GFP_KERNEL | GFP_DMA);
515         if (!sccb)
516                 goto out;
517         assigned = 0;
518         for (id = 0; id <= sclp_max_storage_id; id++) {
519                 memset(sccb, 0, PAGE_SIZE);
520                 sccb->header.length = PAGE_SIZE;
521                 rc = sclp_sync_request(0x00040001 | id << 8, sccb);
522                 if (rc)
523                         goto out;
524                 switch (sccb->header.response_code) {
525                 case 0x0010:
526                         set_bit(id, sclp_storage_ids);
527                         for (i = 0; i < sccb->assigned; i++) {
528                                 if (!sccb->entries[i])
529                                         continue;
530                                 assigned++;
531                                 insert_increment(sccb->entries[i] >> 16, 0, 1);
532                         }
533                         break;
534                 case 0x0310:
535                         break;
536                 case 0x0410:
537                         for (i = 0; i < sccb->assigned; i++) {
538                                 if (!sccb->entries[i])
539                                         continue;
540                                 assigned++;
541                                 insert_increment(sccb->entries[i] >> 16, 1, 1);
542                         }
543                         break;
544                 default:
545                         rc = -EIO;
546                         break;
547                 }
548                 if (!rc)
549                         sclp_max_storage_id = sccb->max_id;
550         }
551         if (rc || list_empty(&sclp_mem_list))
552                 goto out;
553         for (i = 1; i <= sclp_rnmax - assigned; i++)
554                 insert_increment(0, 1, 0);
555         rc = register_memory_notifier(&sclp_mem_nb);
556         if (rc)
557                 goto out;
558         rc = platform_driver_register(&sclp_mem_pdrv);
559         if (rc)
560                 goto out;
561         sclp_pdev = platform_device_register_simple("sclp_mem", -1, NULL, 0);
562         rc = PTR_ERR_OR_ZERO(sclp_pdev);
563         if (rc)
564                 goto out_driver;
565         sclp_add_standby_memory();
566         goto out;
567 out_driver:
568         platform_driver_unregister(&sclp_mem_pdrv);
569 out:
570         free_page((unsigned long) sccb);
571         return rc;
572 }
573 __initcall(sclp_detect_standby_memory);
574
575 #endif /* CONFIG_MEMORY_HOTPLUG */
576
577 /*
578  * PCI I/O adapter configuration related functions.
579  */
580 #define SCLP_CMDW_CONFIGURE_PCI                 0x001a0001
581 #define SCLP_CMDW_DECONFIGURE_PCI               0x001b0001
582
583 #define SCLP_RECONFIG_PCI_ATPYE                 2
584
585 struct pci_cfg_sccb {
586         struct sccb_header header;
587         u8 atype;               /* adapter type */
588         u8 reserved1;
589         u16 reserved2;
590         u32 aid;                /* adapter identifier */
591 } __packed;
592
593 static int do_pci_configure(sclp_cmdw_t cmd, u32 fid)
594 {
595         struct pci_cfg_sccb *sccb;
596         int rc;
597
598         if (!SCLP_HAS_PCI_RECONFIG)
599                 return -EOPNOTSUPP;
600
601         sccb = (struct pci_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
602         if (!sccb)
603                 return -ENOMEM;
604
605         sccb->header.length = PAGE_SIZE;
606         sccb->atype = SCLP_RECONFIG_PCI_ATPYE;
607         sccb->aid = fid;
608         rc = sclp_sync_request(cmd, sccb);
609         if (rc)
610                 goto out;
611         switch (sccb->header.response_code) {
612         case 0x0020:
613         case 0x0120:
614                 break;
615         default:
616                 pr_warn("configure PCI I/O adapter failed: cmd=0x%08x  response=0x%04x\n",
617                         cmd, sccb->header.response_code);
618                 rc = -EIO;
619                 break;
620         }
621 out:
622         free_page((unsigned long) sccb);
623         return rc;
624 }
625
626 int sclp_pci_configure(u32 fid)
627 {
628         return do_pci_configure(SCLP_CMDW_CONFIGURE_PCI, fid);
629 }
630 EXPORT_SYMBOL(sclp_pci_configure);
631
632 int sclp_pci_deconfigure(u32 fid)
633 {
634         return do_pci_configure(SCLP_CMDW_DECONFIGURE_PCI, fid);
635 }
636 EXPORT_SYMBOL(sclp_pci_deconfigure);
637
638 /*
639  * Channel path configuration related functions.
640  */
641
642 #define SCLP_CMDW_CONFIGURE_CHPATH              0x000f0001
643 #define SCLP_CMDW_DECONFIGURE_CHPATH            0x000e0001
644 #define SCLP_CMDW_READ_CHPATH_INFORMATION       0x00030001
645
646 struct chp_cfg_sccb {
647         struct sccb_header header;
648         u8 ccm;
649         u8 reserved[6];
650         u8 cssid;
651 } __attribute__((packed));
652
653 static int do_chp_configure(sclp_cmdw_t cmd)
654 {
655         struct chp_cfg_sccb *sccb;
656         int rc;
657
658         if (!SCLP_HAS_CHP_RECONFIG)
659                 return -EOPNOTSUPP;
660         /* Prepare sccb. */
661         sccb = (struct chp_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
662         if (!sccb)
663                 return -ENOMEM;
664         sccb->header.length = sizeof(*sccb);
665         rc = sclp_sync_request(cmd, sccb);
666         if (rc)
667                 goto out;
668         switch (sccb->header.response_code) {
669         case 0x0020:
670         case 0x0120:
671         case 0x0440:
672         case 0x0450:
673                 break;
674         default:
675                 pr_warning("configure channel-path failed "
676                            "(cmd=0x%08x, response=0x%04x)\n", cmd,
677                            sccb->header.response_code);
678                 rc = -EIO;
679                 break;
680         }
681 out:
682         free_page((unsigned long) sccb);
683         return rc;
684 }
685
686 /**
687  * sclp_chp_configure - perform configure channel-path sclp command
688  * @chpid: channel-path ID
689  *
690  * Perform configure channel-path command sclp command for specified chpid.
691  * Return 0 after command successfully finished, non-zero otherwise.
692  */
693 int sclp_chp_configure(struct chp_id chpid)
694 {
695         return do_chp_configure(SCLP_CMDW_CONFIGURE_CHPATH | chpid.id << 8);
696 }
697
698 /**
699  * sclp_chp_deconfigure - perform deconfigure channel-path sclp command
700  * @chpid: channel-path ID
701  *
702  * Perform deconfigure channel-path command sclp command for specified chpid
703  * and wait for completion. On success return 0. Return non-zero otherwise.
704  */
705 int sclp_chp_deconfigure(struct chp_id chpid)
706 {
707         return do_chp_configure(SCLP_CMDW_DECONFIGURE_CHPATH | chpid.id << 8);
708 }
709
710 struct chp_info_sccb {
711         struct sccb_header header;
712         u8 recognized[SCLP_CHP_INFO_MASK_SIZE];
713         u8 standby[SCLP_CHP_INFO_MASK_SIZE];
714         u8 configured[SCLP_CHP_INFO_MASK_SIZE];
715         u8 ccm;
716         u8 reserved[6];
717         u8 cssid;
718 } __attribute__((packed));
719
720 /**
721  * sclp_chp_read_info - perform read channel-path information sclp command
722  * @info: resulting channel-path information data
723  *
724  * Perform read channel-path information sclp command and wait for completion.
725  * On success, store channel-path information in @info and return 0. Return
726  * non-zero otherwise.
727  */
728 int sclp_chp_read_info(struct sclp_chp_info *info)
729 {
730         struct chp_info_sccb *sccb;
731         int rc;
732
733         if (!SCLP_HAS_CHP_INFO)
734                 return -EOPNOTSUPP;
735         /* Prepare sccb. */
736         sccb = (struct chp_info_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
737         if (!sccb)
738                 return -ENOMEM;
739         sccb->header.length = sizeof(*sccb);
740         rc = sclp_sync_request(SCLP_CMDW_READ_CHPATH_INFORMATION, sccb);
741         if (rc)
742                 goto out;
743         if (sccb->header.response_code != 0x0010) {
744                 pr_warning("read channel-path info failed "
745                            "(response=0x%04x)\n", sccb->header.response_code);
746                 rc = -EIO;
747                 goto out;
748         }
749         memcpy(info->recognized, sccb->recognized, SCLP_CHP_INFO_MASK_SIZE);
750         memcpy(info->standby, sccb->standby, SCLP_CHP_INFO_MASK_SIZE);
751         memcpy(info->configured, sccb->configured, SCLP_CHP_INFO_MASK_SIZE);
752 out:
753         free_page((unsigned long) sccb);
754         return rc;
755 }
756
757 bool sclp_has_sprp(void)
758 {
759         return !!(sclp_fac84 & 0x2);
760 }