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
sclp_cmd_sync_early(sclp_cmdw_t cmd,void * sccb)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_BASE_BITS | PSW_MASK_EXT |
65 PSW_MASK_WAIT | PSW_DEFAULT_KEY);
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
sclp_read_info_early(void)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
sclp_facilities_detect(void)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
sclp_get_rnmax(void)119 unsigned long long sclp_get_rnmax(void)
120 {
121 return rnmax;
122 }
123
sclp_get_rzm(void)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 */
sclp_get_ipl_info(struct sclp_ipl_info * info)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
sclp_sync_callback(struct sclp_req * req,void * data)146 static void sclp_sync_callback(struct sclp_req *req, void *data)
147 {
148 struct completion *completion = data;
149
150 complete(completion);
151 }
152
do_sync_request(sclp_cmdw_t cmd,void * sccb)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
sclp_fill_cpu_info(struct sclp_cpu_info * info,struct read_cpu_info_sccb * sccb)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
sclp_get_cpu_info(struct sclp_cpu_info * info)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
do_cpu_configure(sclp_cmdw_t cmd)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
sclp_cpu_configure(u8 cpu)281 int sclp_cpu_configure(u8 cpu)
282 {
283 return do_cpu_configure(SCLP_CMDW_CONFIGURE_CPU | cpu << 8);
284 }
285
sclp_cpu_deconfigure(u8 cpu)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
arch_get_memory_phys_device(unsigned long start_pfn)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
rn2addr(u16 rn)318 static unsigned long long rn2addr(u16 rn)
319 {
320 return (unsigned long long) (rn - 1) * rzm;
321 }
322
do_assign_storage(sclp_cmdw_t cmd,u16 rn)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
sclp_assign_storage(u16 rn)352 static int sclp_assign_storage(u16 rn)
353 {
354 return do_assign_storage(0x000d0001, rn);
355 }
356
sclp_unassign_storage(u16 rn)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
sclp_attach_storage(u8 id)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 sclp_unassign_storage(sccb->entries[i] >> 16);
388 break;
389 default:
390 rc = -EIO;
391 break;
392 }
393 out:
394 free_page((unsigned long) sccb);
395 return rc;
396 }
397
sclp_mem_change_state(unsigned long start,unsigned long size,int online)398 static int sclp_mem_change_state(unsigned long start, unsigned long size,
399 int online)
400 {
401 struct memory_increment *incr;
402 unsigned long long istart;
403 int rc = 0;
404
405 list_for_each_entry(incr, &sclp_mem_list, list) {
406 istart = rn2addr(incr->rn);
407 if (start + size - 1 < istart)
408 break;
409 if (start > istart + rzm - 1)
410 continue;
411 if (online) {
412 if (incr->usecount++)
413 continue;
414 /*
415 * Don't break the loop if one assign fails. Loop may
416 * be walked again on CANCEL and we can't save
417 * information if state changed before or not.
418 * So continue and increase usecount for all increments.
419 */
420 rc |= sclp_assign_storage(incr->rn);
421 } else {
422 if (--incr->usecount)
423 continue;
424 sclp_unassign_storage(incr->rn);
425 }
426 }
427 return rc ? -EIO : 0;
428 }
429
sclp_mem_notifier(struct notifier_block * nb,unsigned long action,void * data)430 static int sclp_mem_notifier(struct notifier_block *nb,
431 unsigned long action, void *data)
432 {
433 unsigned long start, size;
434 struct memory_notify *arg;
435 unsigned char id;
436 int rc = 0;
437
438 arg = data;
439 start = arg->start_pfn << PAGE_SHIFT;
440 size = arg->nr_pages << PAGE_SHIFT;
441 mutex_lock(&sclp_mem_mutex);
442 for (id = 0; id <= sclp_max_storage_id; id++)
443 if (!test_bit(id, sclp_storage_ids))
444 sclp_attach_storage(id);
445 switch (action) {
446 case MEM_ONLINE:
447 case MEM_GOING_OFFLINE:
448 case MEM_CANCEL_OFFLINE:
449 break;
450 case MEM_GOING_ONLINE:
451 rc = sclp_mem_change_state(start, size, 1);
452 break;
453 case MEM_CANCEL_ONLINE:
454 sclp_mem_change_state(start, size, 0);
455 break;
456 case MEM_OFFLINE:
457 sclp_mem_change_state(start, size, 0);
458 break;
459 default:
460 rc = -EINVAL;
461 break;
462 }
463 if (!rc)
464 sclp_mem_state_changed = 1;
465 mutex_unlock(&sclp_mem_mutex);
466 return rc ? NOTIFY_BAD : NOTIFY_OK;
467 }
468
469 static struct notifier_block sclp_mem_nb = {
470 .notifier_call = sclp_mem_notifier,
471 };
472
add_memory_merged(u16 rn)473 static void __init add_memory_merged(u16 rn)
474 {
475 static u16 first_rn, num;
476 unsigned long long start, size;
477
478 if (rn && first_rn && (first_rn + num == rn)) {
479 num++;
480 return;
481 }
482 if (!first_rn)
483 goto skip_add;
484 start = rn2addr(first_rn);
485 size = (unsigned long long ) num * rzm;
486 if (start >= VMEM_MAX_PHYS)
487 goto skip_add;
488 if (start + size > VMEM_MAX_PHYS)
489 size = VMEM_MAX_PHYS - start;
490 if (memory_end_set && (start >= memory_end))
491 goto skip_add;
492 if (memory_end_set && (start + size > memory_end))
493 size = memory_end - start;
494 add_memory(0, start, size);
495 skip_add:
496 first_rn = rn;
497 num = 1;
498 }
499
sclp_add_standby_memory(void)500 static void __init sclp_add_standby_memory(void)
501 {
502 struct memory_increment *incr;
503
504 list_for_each_entry(incr, &sclp_mem_list, list)
505 if (incr->standby)
506 add_memory_merged(incr->rn);
507 add_memory_merged(0);
508 }
509
insert_increment(u16 rn,int standby,int assigned)510 static void __init insert_increment(u16 rn, int standby, int assigned)
511 {
512 struct memory_increment *incr, *new_incr;
513 struct list_head *prev;
514 u16 last_rn;
515
516 new_incr = kzalloc(sizeof(*new_incr), GFP_KERNEL);
517 if (!new_incr)
518 return;
519 new_incr->rn = rn;
520 new_incr->standby = standby;
521 if (!standby)
522 new_incr->usecount = 1;
523 last_rn = 0;
524 prev = &sclp_mem_list;
525 list_for_each_entry(incr, &sclp_mem_list, list) {
526 if (assigned && incr->rn > rn)
527 break;
528 if (!assigned && incr->rn - last_rn > 1)
529 break;
530 last_rn = incr->rn;
531 prev = &incr->list;
532 }
533 if (!assigned)
534 new_incr->rn = last_rn + 1;
535 if (new_incr->rn > rnmax) {
536 kfree(new_incr);
537 return;
538 }
539 list_add(&new_incr->list, prev);
540 }
541
sclp_mem_freeze(struct device * dev)542 static int sclp_mem_freeze(struct device *dev)
543 {
544 if (!sclp_mem_state_changed)
545 return 0;
546 pr_err("Memory hotplug state changed, suspend refused.\n");
547 return -EPERM;
548 }
549
550 struct read_storage_sccb {
551 struct sccb_header header;
552 u16 max_id;
553 u16 assigned;
554 u16 standby;
555 u16 :16;
556 u32 entries[0];
557 } __packed;
558
559 static const struct dev_pm_ops sclp_mem_pm_ops = {
560 .freeze = sclp_mem_freeze,
561 };
562
563 static struct platform_driver sclp_mem_pdrv = {
564 .driver = {
565 .name = "sclp_mem",
566 .pm = &sclp_mem_pm_ops,
567 },
568 };
569
sclp_detect_standby_memory(void)570 static int __init sclp_detect_standby_memory(void)
571 {
572 struct platform_device *sclp_pdev;
573 struct read_storage_sccb *sccb;
574 int i, id, assigned, rc;
575
576 if (!early_read_info_sccb_valid)
577 return 0;
578 if ((sclp_facilities & 0xe00000000000ULL) != 0xe00000000000ULL)
579 return 0;
580 rc = -ENOMEM;
581 sccb = (void *) __get_free_page(GFP_KERNEL | GFP_DMA);
582 if (!sccb)
583 goto out;
584 assigned = 0;
585 for (id = 0; id <= sclp_max_storage_id; id++) {
586 memset(sccb, 0, PAGE_SIZE);
587 sccb->header.length = PAGE_SIZE;
588 rc = do_sync_request(0x00040001 | id << 8, sccb);
589 if (rc)
590 goto out;
591 switch (sccb->header.response_code) {
592 case 0x0010:
593 set_bit(id, sclp_storage_ids);
594 for (i = 0; i < sccb->assigned; i++) {
595 if (!sccb->entries[i])
596 continue;
597 assigned++;
598 insert_increment(sccb->entries[i] >> 16, 0, 1);
599 }
600 break;
601 case 0x0310:
602 break;
603 case 0x0410:
604 for (i = 0; i < sccb->assigned; i++) {
605 if (!sccb->entries[i])
606 continue;
607 assigned++;
608 insert_increment(sccb->entries[i] >> 16, 1, 1);
609 }
610 break;
611 default:
612 rc = -EIO;
613 break;
614 }
615 if (!rc)
616 sclp_max_storage_id = sccb->max_id;
617 }
618 if (rc || list_empty(&sclp_mem_list))
619 goto out;
620 for (i = 1; i <= rnmax - assigned; i++)
621 insert_increment(0, 1, 0);
622 rc = register_memory_notifier(&sclp_mem_nb);
623 if (rc)
624 goto out;
625 rc = platform_driver_register(&sclp_mem_pdrv);
626 if (rc)
627 goto out;
628 sclp_pdev = platform_device_register_simple("sclp_mem", -1, NULL, 0);
629 rc = IS_ERR(sclp_pdev) ? PTR_ERR(sclp_pdev) : 0;
630 if (rc)
631 goto out_driver;
632 sclp_add_standby_memory();
633 goto out;
634 out_driver:
635 platform_driver_unregister(&sclp_mem_pdrv);
636 out:
637 free_page((unsigned long) sccb);
638 return rc;
639 }
640 __initcall(sclp_detect_standby_memory);
641
642 #endif /* CONFIG_MEMORY_HOTPLUG */
643
644 /*
645 * Channel path configuration related functions.
646 */
647
648 #define SCLP_CMDW_CONFIGURE_CHPATH 0x000f0001
649 #define SCLP_CMDW_DECONFIGURE_CHPATH 0x000e0001
650 #define SCLP_CMDW_READ_CHPATH_INFORMATION 0x00030001
651
652 struct chp_cfg_sccb {
653 struct sccb_header header;
654 u8 ccm;
655 u8 reserved[6];
656 u8 cssid;
657 } __attribute__((packed));
658
do_chp_configure(sclp_cmdw_t cmd)659 static int do_chp_configure(sclp_cmdw_t cmd)
660 {
661 struct chp_cfg_sccb *sccb;
662 int rc;
663
664 if (!SCLP_HAS_CHP_RECONFIG)
665 return -EOPNOTSUPP;
666 /* Prepare sccb. */
667 sccb = (struct chp_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
668 if (!sccb)
669 return -ENOMEM;
670 sccb->header.length = sizeof(*sccb);
671 rc = do_sync_request(cmd, sccb);
672 if (rc)
673 goto out;
674 switch (sccb->header.response_code) {
675 case 0x0020:
676 case 0x0120:
677 case 0x0440:
678 case 0x0450:
679 break;
680 default:
681 pr_warning("configure channel-path failed "
682 "(cmd=0x%08x, response=0x%04x)\n", cmd,
683 sccb->header.response_code);
684 rc = -EIO;
685 break;
686 }
687 out:
688 free_page((unsigned long) sccb);
689 return rc;
690 }
691
692 /**
693 * sclp_chp_configure - perform configure channel-path sclp command
694 * @chpid: channel-path ID
695 *
696 * Perform configure channel-path command sclp command for specified chpid.
697 * Return 0 after command successfully finished, non-zero otherwise.
698 */
sclp_chp_configure(struct chp_id chpid)699 int sclp_chp_configure(struct chp_id chpid)
700 {
701 return do_chp_configure(SCLP_CMDW_CONFIGURE_CHPATH | chpid.id << 8);
702 }
703
704 /**
705 * sclp_chp_deconfigure - perform deconfigure channel-path sclp command
706 * @chpid: channel-path ID
707 *
708 * Perform deconfigure channel-path command sclp command for specified chpid
709 * and wait for completion. On success return 0. Return non-zero otherwise.
710 */
sclp_chp_deconfigure(struct chp_id chpid)711 int sclp_chp_deconfigure(struct chp_id chpid)
712 {
713 return do_chp_configure(SCLP_CMDW_DECONFIGURE_CHPATH | chpid.id << 8);
714 }
715
716 struct chp_info_sccb {
717 struct sccb_header header;
718 u8 recognized[SCLP_CHP_INFO_MASK_SIZE];
719 u8 standby[SCLP_CHP_INFO_MASK_SIZE];
720 u8 configured[SCLP_CHP_INFO_MASK_SIZE];
721 u8 ccm;
722 u8 reserved[6];
723 u8 cssid;
724 } __attribute__((packed));
725
726 /**
727 * sclp_chp_read_info - perform read channel-path information sclp command
728 * @info: resulting channel-path information data
729 *
730 * Perform read channel-path information sclp command and wait for completion.
731 * On success, store channel-path information in @info and return 0. Return
732 * non-zero otherwise.
733 */
sclp_chp_read_info(struct sclp_chp_info * info)734 int sclp_chp_read_info(struct sclp_chp_info *info)
735 {
736 struct chp_info_sccb *sccb;
737 int rc;
738
739 if (!SCLP_HAS_CHP_INFO)
740 return -EOPNOTSUPP;
741 /* Prepare sccb. */
742 sccb = (struct chp_info_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
743 if (!sccb)
744 return -ENOMEM;
745 sccb->header.length = sizeof(*sccb);
746 rc = do_sync_request(SCLP_CMDW_READ_CHPATH_INFORMATION, sccb);
747 if (rc)
748 goto out;
749 if (sccb->header.response_code != 0x0010) {
750 pr_warning("read channel-path info failed "
751 "(response=0x%04x)\n", sccb->header.response_code);
752 rc = -EIO;
753 goto out;
754 }
755 memcpy(info->recognized, sccb->recognized, SCLP_CHP_INFO_MASK_SIZE);
756 memcpy(info->standby, sccb->standby, SCLP_CHP_INFO_MASK_SIZE);
757 memcpy(info->configured, sccb->configured, SCLP_CHP_INFO_MASK_SIZE);
758 out:
759 free_page((unsigned long) sccb);
760 return rc;
761 }
762