xref: /linux/drivers/s390/cio/chsc.c (revision a8b70ccf10e38775785d9cb12ead916474549f99)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *   S/390 common I/O routines -- channel subsystem call
4  *
5  *    Copyright IBM Corp. 1999,2012
6  *    Author(s): Ingo Adlung (adlung@de.ibm.com)
7  *		 Cornelia Huck (cornelia.huck@de.ibm.com)
8  *		 Arnd Bergmann (arndb@de.ibm.com)
9  */
10 
11 #define KMSG_COMPONENT "cio"
12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13 
14 #include <linux/module.h>
15 #include <linux/slab.h>
16 #include <linux/init.h>
17 #include <linux/device.h>
18 #include <linux/mutex.h>
19 #include <linux/pci.h>
20 
21 #include <asm/cio.h>
22 #include <asm/chpid.h>
23 #include <asm/chsc.h>
24 #include <asm/crw.h>
25 #include <asm/isc.h>
26 #include <asm/ebcdic.h>
27 
28 #include "css.h"
29 #include "cio.h"
30 #include "cio_debug.h"
31 #include "ioasm.h"
32 #include "chp.h"
33 #include "chsc.h"
34 
35 static void *sei_page;
36 static void *chsc_page;
37 static DEFINE_SPINLOCK(chsc_page_lock);
38 
39 /**
40  * chsc_error_from_response() - convert a chsc response to an error
41  * @response: chsc response code
42  *
43  * Returns an appropriate Linux error code for @response.
44  */
45 int chsc_error_from_response(int response)
46 {
47 	switch (response) {
48 	case 0x0001:
49 		return 0;
50 	case 0x0002:
51 	case 0x0003:
52 	case 0x0006:
53 	case 0x0007:
54 	case 0x0008:
55 	case 0x000a:
56 	case 0x0104:
57 		return -EINVAL;
58 	case 0x0004:
59 		return -EOPNOTSUPP;
60 	case 0x000b:
61 	case 0x0107:		/* "Channel busy" for the op 0x003d */
62 		return -EBUSY;
63 	case 0x0100:
64 	case 0x0102:
65 		return -ENOMEM;
66 	default:
67 		return -EIO;
68 	}
69 }
70 EXPORT_SYMBOL_GPL(chsc_error_from_response);
71 
72 struct chsc_ssd_area {
73 	struct chsc_header request;
74 	u16 :10;
75 	u16 ssid:2;
76 	u16 :4;
77 	u16 f_sch;	  /* first subchannel */
78 	u16 :16;
79 	u16 l_sch;	  /* last subchannel */
80 	u32 :32;
81 	struct chsc_header response;
82 	u32 :32;
83 	u8 sch_valid : 1;
84 	u8 dev_valid : 1;
85 	u8 st	     : 3; /* subchannel type */
86 	u8 zeroes    : 3;
87 	u8  unit_addr;	  /* unit address */
88 	u16 devno;	  /* device number */
89 	u8 path_mask;
90 	u8 fla_valid_mask;
91 	u16 sch;	  /* subchannel */
92 	u8 chpid[8];	  /* chpids 0-7 */
93 	u16 fla[8];	  /* full link addresses 0-7 */
94 } __attribute__ ((packed));
95 
96 int chsc_get_ssd_info(struct subchannel_id schid, struct chsc_ssd_info *ssd)
97 {
98 	struct chsc_ssd_area *ssd_area;
99 	unsigned long flags;
100 	int ccode;
101 	int ret;
102 	int i;
103 	int mask;
104 
105 	spin_lock_irqsave(&chsc_page_lock, flags);
106 	memset(chsc_page, 0, PAGE_SIZE);
107 	ssd_area = chsc_page;
108 	ssd_area->request.length = 0x0010;
109 	ssd_area->request.code = 0x0004;
110 	ssd_area->ssid = schid.ssid;
111 	ssd_area->f_sch = schid.sch_no;
112 	ssd_area->l_sch = schid.sch_no;
113 
114 	ccode = chsc(ssd_area);
115 	/* Check response. */
116 	if (ccode > 0) {
117 		ret = (ccode == 3) ? -ENODEV : -EBUSY;
118 		goto out;
119 	}
120 	ret = chsc_error_from_response(ssd_area->response.code);
121 	if (ret != 0) {
122 		CIO_MSG_EVENT(2, "chsc: ssd failed for 0.%x.%04x (rc=%04x)\n",
123 			      schid.ssid, schid.sch_no,
124 			      ssd_area->response.code);
125 		goto out;
126 	}
127 	if (!ssd_area->sch_valid) {
128 		ret = -ENODEV;
129 		goto out;
130 	}
131 	/* Copy data */
132 	ret = 0;
133 	memset(ssd, 0, sizeof(struct chsc_ssd_info));
134 	if ((ssd_area->st != SUBCHANNEL_TYPE_IO) &&
135 	    (ssd_area->st != SUBCHANNEL_TYPE_MSG))
136 		goto out;
137 	ssd->path_mask = ssd_area->path_mask;
138 	ssd->fla_valid_mask = ssd_area->fla_valid_mask;
139 	for (i = 0; i < 8; i++) {
140 		mask = 0x80 >> i;
141 		if (ssd_area->path_mask & mask) {
142 			chp_id_init(&ssd->chpid[i]);
143 			ssd->chpid[i].id = ssd_area->chpid[i];
144 		}
145 		if (ssd_area->fla_valid_mask & mask)
146 			ssd->fla[i] = ssd_area->fla[i];
147 	}
148 out:
149 	spin_unlock_irqrestore(&chsc_page_lock, flags);
150 	return ret;
151 }
152 
153 /**
154  * chsc_ssqd() - store subchannel QDIO data (SSQD)
155  * @schid: id of the subchannel on which SSQD is performed
156  * @ssqd: request and response block for SSQD
157  *
158  * Returns 0 on success.
159  */
160 int chsc_ssqd(struct subchannel_id schid, struct chsc_ssqd_area *ssqd)
161 {
162 	memset(ssqd, 0, sizeof(*ssqd));
163 	ssqd->request.length = 0x0010;
164 	ssqd->request.code = 0x0024;
165 	ssqd->first_sch = schid.sch_no;
166 	ssqd->last_sch = schid.sch_no;
167 	ssqd->ssid = schid.ssid;
168 
169 	if (chsc(ssqd))
170 		return -EIO;
171 
172 	return chsc_error_from_response(ssqd->response.code);
173 }
174 EXPORT_SYMBOL_GPL(chsc_ssqd);
175 
176 /**
177  * chsc_sadc() - set adapter device controls (SADC)
178  * @schid: id of the subchannel on which SADC is performed
179  * @scssc: request and response block for SADC
180  * @summary_indicator_addr: summary indicator address
181  * @subchannel_indicator_addr: subchannel indicator address
182  *
183  * Returns 0 on success.
184  */
185 int chsc_sadc(struct subchannel_id schid, struct chsc_scssc_area *scssc,
186 	      u64 summary_indicator_addr, u64 subchannel_indicator_addr)
187 {
188 	memset(scssc, 0, sizeof(*scssc));
189 	scssc->request.length = 0x0fe0;
190 	scssc->request.code = 0x0021;
191 	scssc->operation_code = 0;
192 
193 	scssc->summary_indicator_addr = summary_indicator_addr;
194 	scssc->subchannel_indicator_addr = subchannel_indicator_addr;
195 
196 	scssc->ks = PAGE_DEFAULT_KEY >> 4;
197 	scssc->kc = PAGE_DEFAULT_KEY >> 4;
198 	scssc->isc = QDIO_AIRQ_ISC;
199 	scssc->schid = schid;
200 
201 	/* enable the time delay disablement facility */
202 	if (css_general_characteristics.aif_tdd)
203 		scssc->word_with_d_bit = 0x10000000;
204 
205 	if (chsc(scssc))
206 		return -EIO;
207 
208 	return chsc_error_from_response(scssc->response.code);
209 }
210 EXPORT_SYMBOL_GPL(chsc_sadc);
211 
212 static int s390_subchannel_remove_chpid(struct subchannel *sch, void *data)
213 {
214 	spin_lock_irq(sch->lock);
215 	if (sch->driver && sch->driver->chp_event)
216 		if (sch->driver->chp_event(sch, data, CHP_OFFLINE) != 0)
217 			goto out_unreg;
218 	spin_unlock_irq(sch->lock);
219 	return 0;
220 
221 out_unreg:
222 	sch->lpm = 0;
223 	spin_unlock_irq(sch->lock);
224 	css_schedule_eval(sch->schid);
225 	return 0;
226 }
227 
228 void chsc_chp_offline(struct chp_id chpid)
229 {
230 	struct channel_path *chp = chpid_to_chp(chpid);
231 	struct chp_link link;
232 	char dbf_txt[15];
233 
234 	sprintf(dbf_txt, "chpr%x.%02x", chpid.cssid, chpid.id);
235 	CIO_TRACE_EVENT(2, dbf_txt);
236 
237 	if (chp_get_status(chpid) <= 0)
238 		return;
239 	memset(&link, 0, sizeof(struct chp_link));
240 	link.chpid = chpid;
241 	/* Wait until previous actions have settled. */
242 	css_wait_for_slow_path();
243 
244 	mutex_lock(&chp->lock);
245 	chp_update_desc(chp);
246 	mutex_unlock(&chp->lock);
247 
248 	for_each_subchannel_staged(s390_subchannel_remove_chpid, NULL, &link);
249 }
250 
251 static int __s390_process_res_acc(struct subchannel *sch, void *data)
252 {
253 	spin_lock_irq(sch->lock);
254 	if (sch->driver && sch->driver->chp_event)
255 		sch->driver->chp_event(sch, data, CHP_ONLINE);
256 	spin_unlock_irq(sch->lock);
257 
258 	return 0;
259 }
260 
261 static void s390_process_res_acc(struct chp_link *link)
262 {
263 	char dbf_txt[15];
264 
265 	sprintf(dbf_txt, "accpr%x.%02x", link->chpid.cssid,
266 		link->chpid.id);
267 	CIO_TRACE_EVENT( 2, dbf_txt);
268 	if (link->fla != 0) {
269 		sprintf(dbf_txt, "fla%x", link->fla);
270 		CIO_TRACE_EVENT( 2, dbf_txt);
271 	}
272 	/* Wait until previous actions have settled. */
273 	css_wait_for_slow_path();
274 	/*
275 	 * I/O resources may have become accessible.
276 	 * Scan through all subchannels that may be concerned and
277 	 * do a validation on those.
278 	 * The more information we have (info), the less scanning
279 	 * will we have to do.
280 	 */
281 	for_each_subchannel_staged(__s390_process_res_acc, NULL, link);
282 	css_schedule_reprobe();
283 }
284 
285 struct chsc_sei_nt0_area {
286 	u8  flags;
287 	u8  vf;				/* validity flags */
288 	u8  rs;				/* reporting source */
289 	u8  cc;				/* content code */
290 	u16 fla;			/* full link address */
291 	u16 rsid;			/* reporting source id */
292 	u32 reserved1;
293 	u32 reserved2;
294 	/* ccdf has to be big enough for a link-incident record */
295 	u8  ccdf[PAGE_SIZE - 24 - 16];	/* content-code dependent field */
296 } __packed;
297 
298 struct chsc_sei_nt2_area {
299 	u8  flags;			/* p and v bit */
300 	u8  reserved1;
301 	u8  reserved2;
302 	u8  cc;				/* content code */
303 	u32 reserved3[13];
304 	u8  ccdf[PAGE_SIZE - 24 - 56];	/* content-code dependent field */
305 } __packed;
306 
307 #define CHSC_SEI_NT0	(1ULL << 63)
308 #define CHSC_SEI_NT2	(1ULL << 61)
309 
310 struct chsc_sei {
311 	struct chsc_header request;
312 	u32 reserved1;
313 	u64 ntsm;			/* notification type mask */
314 	struct chsc_header response;
315 	u32 :24;
316 	u8 nt;
317 	union {
318 		struct chsc_sei_nt0_area nt0_area;
319 		struct chsc_sei_nt2_area nt2_area;
320 		u8 nt_area[PAGE_SIZE - 24];
321 	} u;
322 } __packed;
323 
324 /*
325  * Node Descriptor as defined in SA22-7204, "Common I/O-Device Commands"
326  */
327 
328 #define ND_VALIDITY_VALID	0
329 #define ND_VALIDITY_OUTDATED	1
330 #define ND_VALIDITY_INVALID	2
331 
332 struct node_descriptor {
333 	/* Flags. */
334 	union {
335 		struct {
336 			u32 validity:3;
337 			u32 reserved:5;
338 		} __packed;
339 		u8 byte0;
340 	} __packed;
341 
342 	/* Node parameters. */
343 	u32 params:24;
344 
345 	/* Node ID. */
346 	char type[6];
347 	char model[3];
348 	char manufacturer[3];
349 	char plant[2];
350 	char seq[12];
351 	u16 tag;
352 } __packed;
353 
354 /*
355  * Link Incident Record as defined in SA22-7202, "ESCON I/O Interface"
356  */
357 
358 #define LIR_IQ_CLASS_INFO		0
359 #define LIR_IQ_CLASS_DEGRADED		1
360 #define LIR_IQ_CLASS_NOT_OPERATIONAL	2
361 
362 struct lir {
363 	struct {
364 		u32 null:1;
365 		u32 reserved:3;
366 		u32 class:2;
367 		u32 reserved2:2;
368 	} __packed iq;
369 	u32 ic:8;
370 	u32 reserved:16;
371 	struct node_descriptor incident_node;
372 	struct node_descriptor attached_node;
373 	u8 reserved2[32];
374 } __packed;
375 
376 #define PARAMS_LEN	10	/* PARAMS=xx,xxxxxx */
377 #define NODEID_LEN	35	/* NODEID=tttttt/mdl,mmm.ppssssssssssss,xxxx */
378 
379 /* Copy EBCIDC text, convert to ASCII and optionally add delimiter. */
380 static char *store_ebcdic(char *dest, const char *src, unsigned long len,
381 			  char delim)
382 {
383 	memcpy(dest, src, len);
384 	EBCASC(dest, len);
385 
386 	if (delim)
387 		dest[len++] = delim;
388 
389 	return dest + len;
390 }
391 
392 /* Format node ID and parameters for output in LIR log message. */
393 static void format_node_data(char *params, char *id, struct node_descriptor *nd)
394 {
395 	memset(params, 0, PARAMS_LEN);
396 	memset(id, 0, NODEID_LEN);
397 
398 	if (nd->validity != ND_VALIDITY_VALID) {
399 		strncpy(params, "n/a", PARAMS_LEN - 1);
400 		strncpy(id, "n/a", NODEID_LEN - 1);
401 		return;
402 	}
403 
404 	/* PARAMS=xx,xxxxxx */
405 	snprintf(params, PARAMS_LEN, "%02x,%06x", nd->byte0, nd->params);
406 	/* NODEID=tttttt/mdl,mmm.ppssssssssssss,xxxx */
407 	id = store_ebcdic(id, nd->type, sizeof(nd->type), '/');
408 	id = store_ebcdic(id, nd->model, sizeof(nd->model), ',');
409 	id = store_ebcdic(id, nd->manufacturer, sizeof(nd->manufacturer), '.');
410 	id = store_ebcdic(id, nd->plant, sizeof(nd->plant), 0);
411 	id = store_ebcdic(id, nd->seq, sizeof(nd->seq), ',');
412 	sprintf(id, "%04X", nd->tag);
413 }
414 
415 static void chsc_process_sei_link_incident(struct chsc_sei_nt0_area *sei_area)
416 {
417 	struct lir *lir = (struct lir *) &sei_area->ccdf;
418 	char iuparams[PARAMS_LEN], iunodeid[NODEID_LEN], auparams[PARAMS_LEN],
419 	     aunodeid[NODEID_LEN];
420 
421 	CIO_CRW_EVENT(4, "chsc: link incident (rs=%02x, rs_id=%04x, iq=%02x)\n",
422 		      sei_area->rs, sei_area->rsid, sei_area->ccdf[0]);
423 
424 	/* Ignore NULL Link Incident Records. */
425 	if (lir->iq.null)
426 		return;
427 
428 	/* Inform user that a link requires maintenance actions because it has
429 	 * become degraded or not operational. Note that this log message is
430 	 * the primary intention behind a Link Incident Record. */
431 
432 	format_node_data(iuparams, iunodeid, &lir->incident_node);
433 	format_node_data(auparams, aunodeid, &lir->attached_node);
434 
435 	switch (lir->iq.class) {
436 	case LIR_IQ_CLASS_DEGRADED:
437 		pr_warn("Link degraded: RS=%02x RSID=%04x IC=%02x "
438 			"IUPARAMS=%s IUNODEID=%s AUPARAMS=%s AUNODEID=%s\n",
439 			sei_area->rs, sei_area->rsid, lir->ic, iuparams,
440 			iunodeid, auparams, aunodeid);
441 		break;
442 	case LIR_IQ_CLASS_NOT_OPERATIONAL:
443 		pr_err("Link stopped: RS=%02x RSID=%04x IC=%02x "
444 		       "IUPARAMS=%s IUNODEID=%s AUPARAMS=%s AUNODEID=%s\n",
445 		       sei_area->rs, sei_area->rsid, lir->ic, iuparams,
446 		       iunodeid, auparams, aunodeid);
447 		break;
448 	default:
449 		break;
450 	}
451 }
452 
453 static void chsc_process_sei_res_acc(struct chsc_sei_nt0_area *sei_area)
454 {
455 	struct chp_link link;
456 	struct chp_id chpid;
457 	int status;
458 
459 	CIO_CRW_EVENT(4, "chsc: resource accessibility event (rs=%02x, "
460 		      "rs_id=%04x)\n", sei_area->rs, sei_area->rsid);
461 	if (sei_area->rs != 4)
462 		return;
463 	chp_id_init(&chpid);
464 	chpid.id = sei_area->rsid;
465 	/* allocate a new channel path structure, if needed */
466 	status = chp_get_status(chpid);
467 	if (status < 0)
468 		chp_new(chpid);
469 	else if (!status)
470 		return;
471 	memset(&link, 0, sizeof(struct chp_link));
472 	link.chpid = chpid;
473 	if ((sei_area->vf & 0xc0) != 0) {
474 		link.fla = sei_area->fla;
475 		if ((sei_area->vf & 0xc0) == 0xc0)
476 			/* full link address */
477 			link.fla_mask = 0xffff;
478 		else
479 			/* link address */
480 			link.fla_mask = 0xff00;
481 	}
482 	s390_process_res_acc(&link);
483 }
484 
485 static void chsc_process_sei_chp_avail(struct chsc_sei_nt0_area *sei_area)
486 {
487 	struct channel_path *chp;
488 	struct chp_id chpid;
489 	u8 *data;
490 	int num;
491 
492 	CIO_CRW_EVENT(4, "chsc: channel path availability information\n");
493 	if (sei_area->rs != 0)
494 		return;
495 	data = sei_area->ccdf;
496 	chp_id_init(&chpid);
497 	for (num = 0; num <= __MAX_CHPID; num++) {
498 		if (!chp_test_bit(data, num))
499 			continue;
500 		chpid.id = num;
501 
502 		CIO_CRW_EVENT(4, "Update information for channel path "
503 			      "%x.%02x\n", chpid.cssid, chpid.id);
504 		chp = chpid_to_chp(chpid);
505 		if (!chp) {
506 			chp_new(chpid);
507 			continue;
508 		}
509 		mutex_lock(&chp->lock);
510 		chp_update_desc(chp);
511 		mutex_unlock(&chp->lock);
512 	}
513 }
514 
515 struct chp_config_data {
516 	u8 map[32];
517 	u8 op;
518 	u8 pc;
519 };
520 
521 static void chsc_process_sei_chp_config(struct chsc_sei_nt0_area *sei_area)
522 {
523 	struct chp_config_data *data;
524 	struct chp_id chpid;
525 	int num;
526 	char *events[3] = {"configure", "deconfigure", "cancel deconfigure"};
527 
528 	CIO_CRW_EVENT(4, "chsc: channel-path-configuration notification\n");
529 	if (sei_area->rs != 0)
530 		return;
531 	data = (struct chp_config_data *) &(sei_area->ccdf);
532 	chp_id_init(&chpid);
533 	for (num = 0; num <= __MAX_CHPID; num++) {
534 		if (!chp_test_bit(data->map, num))
535 			continue;
536 		chpid.id = num;
537 		pr_notice("Processing %s for channel path %x.%02x\n",
538 			  events[data->op], chpid.cssid, chpid.id);
539 		switch (data->op) {
540 		case 0:
541 			chp_cfg_schedule(chpid, 1);
542 			break;
543 		case 1:
544 			chp_cfg_schedule(chpid, 0);
545 			break;
546 		case 2:
547 			chp_cfg_cancel_deconfigure(chpid);
548 			break;
549 		}
550 	}
551 }
552 
553 static void chsc_process_sei_scm_change(struct chsc_sei_nt0_area *sei_area)
554 {
555 	int ret;
556 
557 	CIO_CRW_EVENT(4, "chsc: scm change notification\n");
558 	if (sei_area->rs != 7)
559 		return;
560 
561 	ret = scm_update_information();
562 	if (ret)
563 		CIO_CRW_EVENT(0, "chsc: updating change notification"
564 			      " failed (rc=%d).\n", ret);
565 }
566 
567 static void chsc_process_sei_scm_avail(struct chsc_sei_nt0_area *sei_area)
568 {
569 	int ret;
570 
571 	CIO_CRW_EVENT(4, "chsc: scm available information\n");
572 	if (sei_area->rs != 7)
573 		return;
574 
575 	ret = scm_process_availability_information();
576 	if (ret)
577 		CIO_CRW_EVENT(0, "chsc: process availability information"
578 			      " failed (rc=%d).\n", ret);
579 }
580 
581 static void chsc_process_sei_nt2(struct chsc_sei_nt2_area *sei_area)
582 {
583 	switch (sei_area->cc) {
584 	case 1:
585 		zpci_event_error(sei_area->ccdf);
586 		break;
587 	case 2:
588 		zpci_event_availability(sei_area->ccdf);
589 		break;
590 	default:
591 		CIO_CRW_EVENT(2, "chsc: sei nt2 unhandled cc=%d\n",
592 			      sei_area->cc);
593 		break;
594 	}
595 }
596 
597 static void chsc_process_sei_nt0(struct chsc_sei_nt0_area *sei_area)
598 {
599 	/* which kind of information was stored? */
600 	switch (sei_area->cc) {
601 	case 1: /* link incident*/
602 		chsc_process_sei_link_incident(sei_area);
603 		break;
604 	case 2: /* i/o resource accessibility */
605 		chsc_process_sei_res_acc(sei_area);
606 		break;
607 	case 7: /* channel-path-availability information */
608 		chsc_process_sei_chp_avail(sei_area);
609 		break;
610 	case 8: /* channel-path-configuration notification */
611 		chsc_process_sei_chp_config(sei_area);
612 		break;
613 	case 12: /* scm change notification */
614 		chsc_process_sei_scm_change(sei_area);
615 		break;
616 	case 14: /* scm available notification */
617 		chsc_process_sei_scm_avail(sei_area);
618 		break;
619 	default: /* other stuff */
620 		CIO_CRW_EVENT(2, "chsc: sei nt0 unhandled cc=%d\n",
621 			      sei_area->cc);
622 		break;
623 	}
624 
625 	/* Check if we might have lost some information. */
626 	if (sei_area->flags & 0x40) {
627 		CIO_CRW_EVENT(2, "chsc: event overflow\n");
628 		css_schedule_eval_all();
629 	}
630 }
631 
632 static void chsc_process_event_information(struct chsc_sei *sei, u64 ntsm)
633 {
634 	static int ntsm_unsupported;
635 
636 	while (true) {
637 		memset(sei, 0, sizeof(*sei));
638 		sei->request.length = 0x0010;
639 		sei->request.code = 0x000e;
640 		if (!ntsm_unsupported)
641 			sei->ntsm = ntsm;
642 
643 		if (chsc(sei))
644 			break;
645 
646 		if (sei->response.code != 0x0001) {
647 			CIO_CRW_EVENT(2, "chsc: sei failed (rc=%04x, ntsm=%llx)\n",
648 				      sei->response.code, sei->ntsm);
649 
650 			if (sei->response.code == 3 && sei->ntsm) {
651 				/* Fallback for old firmware. */
652 				ntsm_unsupported = 1;
653 				continue;
654 			}
655 			break;
656 		}
657 
658 		CIO_CRW_EVENT(2, "chsc: sei successful (nt=%d)\n", sei->nt);
659 		switch (sei->nt) {
660 		case 0:
661 			chsc_process_sei_nt0(&sei->u.nt0_area);
662 			break;
663 		case 2:
664 			chsc_process_sei_nt2(&sei->u.nt2_area);
665 			break;
666 		default:
667 			CIO_CRW_EVENT(2, "chsc: unhandled nt: %d\n", sei->nt);
668 			break;
669 		}
670 
671 		if (!(sei->u.nt0_area.flags & 0x80))
672 			break;
673 	}
674 }
675 
676 /*
677  * Handle channel subsystem related CRWs.
678  * Use store event information to find out what's going on.
679  *
680  * Note: Access to sei_page is serialized through machine check handler
681  * thread, so no need for locking.
682  */
683 static void chsc_process_crw(struct crw *crw0, struct crw *crw1, int overflow)
684 {
685 	struct chsc_sei *sei = sei_page;
686 
687 	if (overflow) {
688 		css_schedule_eval_all();
689 		return;
690 	}
691 	CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, "
692 		      "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
693 		      crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
694 		      crw0->erc, crw0->rsid);
695 
696 	CIO_TRACE_EVENT(2, "prcss");
697 	chsc_process_event_information(sei, CHSC_SEI_NT0 | CHSC_SEI_NT2);
698 }
699 
700 void chsc_chp_online(struct chp_id chpid)
701 {
702 	struct channel_path *chp = chpid_to_chp(chpid);
703 	struct chp_link link;
704 	char dbf_txt[15];
705 
706 	sprintf(dbf_txt, "cadd%x.%02x", chpid.cssid, chpid.id);
707 	CIO_TRACE_EVENT(2, dbf_txt);
708 
709 	if (chp_get_status(chpid) != 0) {
710 		memset(&link, 0, sizeof(struct chp_link));
711 		link.chpid = chpid;
712 		/* Wait until previous actions have settled. */
713 		css_wait_for_slow_path();
714 
715 		mutex_lock(&chp->lock);
716 		chp_update_desc(chp);
717 		mutex_unlock(&chp->lock);
718 
719 		for_each_subchannel_staged(__s390_process_res_acc, NULL,
720 					   &link);
721 		css_schedule_reprobe();
722 	}
723 }
724 
725 static void __s390_subchannel_vary_chpid(struct subchannel *sch,
726 					 struct chp_id chpid, int on)
727 {
728 	unsigned long flags;
729 	struct chp_link link;
730 
731 	memset(&link, 0, sizeof(struct chp_link));
732 	link.chpid = chpid;
733 	spin_lock_irqsave(sch->lock, flags);
734 	if (sch->driver && sch->driver->chp_event)
735 		sch->driver->chp_event(sch, &link,
736 				       on ? CHP_VARY_ON : CHP_VARY_OFF);
737 	spin_unlock_irqrestore(sch->lock, flags);
738 }
739 
740 static int s390_subchannel_vary_chpid_off(struct subchannel *sch, void *data)
741 {
742 	struct chp_id *chpid = data;
743 
744 	__s390_subchannel_vary_chpid(sch, *chpid, 0);
745 	return 0;
746 }
747 
748 static int s390_subchannel_vary_chpid_on(struct subchannel *sch, void *data)
749 {
750 	struct chp_id *chpid = data;
751 
752 	__s390_subchannel_vary_chpid(sch, *chpid, 1);
753 	return 0;
754 }
755 
756 /**
757  * chsc_chp_vary - propagate channel-path vary operation to subchannels
758  * @chpid: channl-path ID
759  * @on: non-zero for vary online, zero for vary offline
760  */
761 int chsc_chp_vary(struct chp_id chpid, int on)
762 {
763 	struct channel_path *chp = chpid_to_chp(chpid);
764 
765 	/* Wait until previous actions have settled. */
766 	css_wait_for_slow_path();
767 	/*
768 	 * Redo PathVerification on the devices the chpid connects to
769 	 */
770 	if (on) {
771 		/* Try to update the channel path description. */
772 		chp_update_desc(chp);
773 		for_each_subchannel_staged(s390_subchannel_vary_chpid_on,
774 					   NULL, &chpid);
775 		css_schedule_reprobe();
776 	} else
777 		for_each_subchannel_staged(s390_subchannel_vary_chpid_off,
778 					   NULL, &chpid);
779 
780 	return 0;
781 }
782 
783 static void
784 chsc_remove_cmg_attr(struct channel_subsystem *css)
785 {
786 	int i;
787 
788 	for (i = 0; i <= __MAX_CHPID; i++) {
789 		if (!css->chps[i])
790 			continue;
791 		chp_remove_cmg_attr(css->chps[i]);
792 	}
793 }
794 
795 static int
796 chsc_add_cmg_attr(struct channel_subsystem *css)
797 {
798 	int i, ret;
799 
800 	ret = 0;
801 	for (i = 0; i <= __MAX_CHPID; i++) {
802 		if (!css->chps[i])
803 			continue;
804 		ret = chp_add_cmg_attr(css->chps[i]);
805 		if (ret)
806 			goto cleanup;
807 	}
808 	return ret;
809 cleanup:
810 	for (--i; i >= 0; i--) {
811 		if (!css->chps[i])
812 			continue;
813 		chp_remove_cmg_attr(css->chps[i]);
814 	}
815 	return ret;
816 }
817 
818 int __chsc_do_secm(struct channel_subsystem *css, int enable)
819 {
820 	struct {
821 		struct chsc_header request;
822 		u32 operation_code : 2;
823 		u32 : 30;
824 		u32 key : 4;
825 		u32 : 28;
826 		u32 zeroes1;
827 		u32 cub_addr1;
828 		u32 zeroes2;
829 		u32 cub_addr2;
830 		u32 reserved[13];
831 		struct chsc_header response;
832 		u32 status : 8;
833 		u32 : 4;
834 		u32 fmt : 4;
835 		u32 : 16;
836 	} __attribute__ ((packed)) *secm_area;
837 	unsigned long flags;
838 	int ret, ccode;
839 
840 	spin_lock_irqsave(&chsc_page_lock, flags);
841 	memset(chsc_page, 0, PAGE_SIZE);
842 	secm_area = chsc_page;
843 	secm_area->request.length = 0x0050;
844 	secm_area->request.code = 0x0016;
845 
846 	secm_area->key = PAGE_DEFAULT_KEY >> 4;
847 	secm_area->cub_addr1 = (u64)(unsigned long)css->cub_addr1;
848 	secm_area->cub_addr2 = (u64)(unsigned long)css->cub_addr2;
849 
850 	secm_area->operation_code = enable ? 0 : 1;
851 
852 	ccode = chsc(secm_area);
853 	if (ccode > 0) {
854 		ret = (ccode == 3) ? -ENODEV : -EBUSY;
855 		goto out;
856 	}
857 
858 	switch (secm_area->response.code) {
859 	case 0x0102:
860 	case 0x0103:
861 		ret = -EINVAL;
862 		break;
863 	default:
864 		ret = chsc_error_from_response(secm_area->response.code);
865 	}
866 	if (ret != 0)
867 		CIO_CRW_EVENT(2, "chsc: secm failed (rc=%04x)\n",
868 			      secm_area->response.code);
869 out:
870 	spin_unlock_irqrestore(&chsc_page_lock, flags);
871 	return ret;
872 }
873 
874 int
875 chsc_secm(struct channel_subsystem *css, int enable)
876 {
877 	int ret;
878 
879 	if (enable && !css->cm_enabled) {
880 		css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
881 		css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
882 		if (!css->cub_addr1 || !css->cub_addr2) {
883 			free_page((unsigned long)css->cub_addr1);
884 			free_page((unsigned long)css->cub_addr2);
885 			return -ENOMEM;
886 		}
887 	}
888 	ret = __chsc_do_secm(css, enable);
889 	if (!ret) {
890 		css->cm_enabled = enable;
891 		if (css->cm_enabled) {
892 			ret = chsc_add_cmg_attr(css);
893 			if (ret) {
894 				__chsc_do_secm(css, 0);
895 				css->cm_enabled = 0;
896 			}
897 		} else
898 			chsc_remove_cmg_attr(css);
899 	}
900 	if (!css->cm_enabled) {
901 		free_page((unsigned long)css->cub_addr1);
902 		free_page((unsigned long)css->cub_addr2);
903 	}
904 	return ret;
905 }
906 
907 int chsc_determine_channel_path_desc(struct chp_id chpid, int fmt, int rfmt,
908 				     int c, int m, void *page)
909 {
910 	struct chsc_scpd *scpd_area;
911 	int ccode, ret;
912 
913 	if ((rfmt == 1 || rfmt == 0) && c == 1 &&
914 	    !css_general_characteristics.fcs)
915 		return -EINVAL;
916 	if ((rfmt == 2) && !css_general_characteristics.cib)
917 		return -EINVAL;
918 	if ((rfmt == 3) && !css_general_characteristics.util_str)
919 		return -EINVAL;
920 
921 	memset(page, 0, PAGE_SIZE);
922 	scpd_area = page;
923 	scpd_area->request.length = 0x0010;
924 	scpd_area->request.code = 0x0002;
925 	scpd_area->cssid = chpid.cssid;
926 	scpd_area->first_chpid = chpid.id;
927 	scpd_area->last_chpid = chpid.id;
928 	scpd_area->m = m;
929 	scpd_area->c = c;
930 	scpd_area->fmt = fmt;
931 	scpd_area->rfmt = rfmt;
932 
933 	ccode = chsc(scpd_area);
934 	if (ccode > 0)
935 		return (ccode == 3) ? -ENODEV : -EBUSY;
936 
937 	ret = chsc_error_from_response(scpd_area->response.code);
938 	if (ret)
939 		CIO_CRW_EVENT(2, "chsc: scpd failed (rc=%04x)\n",
940 			      scpd_area->response.code);
941 	return ret;
942 }
943 EXPORT_SYMBOL_GPL(chsc_determine_channel_path_desc);
944 
945 #define chsc_det_chp_desc(FMT, c)					\
946 int chsc_determine_fmt##FMT##_channel_path_desc(			\
947 	struct chp_id chpid, struct channel_path_desc_fmt##FMT *desc)	\
948 {									\
949 	struct chsc_scpd *scpd_area;					\
950 	unsigned long flags;						\
951 	int ret;							\
952 									\
953 	spin_lock_irqsave(&chsc_page_lock, flags);			\
954 	scpd_area = chsc_page;						\
955 	ret = chsc_determine_channel_path_desc(chpid, 0, FMT, c, 0,	\
956 					       scpd_area);		\
957 	if (ret)							\
958 		goto out;						\
959 									\
960 	memcpy(desc, scpd_area->data, sizeof(*desc));			\
961 out:									\
962 	spin_unlock_irqrestore(&chsc_page_lock, flags);			\
963 	return ret;							\
964 }
965 
966 chsc_det_chp_desc(0, 0)
967 chsc_det_chp_desc(1, 1)
968 chsc_det_chp_desc(3, 0)
969 
970 static void
971 chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
972 			  struct cmg_chars *chars)
973 {
974 	int i, mask;
975 
976 	for (i = 0; i < NR_MEASUREMENT_CHARS; i++) {
977 		mask = 0x80 >> (i + 3);
978 		if (cmcv & mask)
979 			chp->cmg_chars.values[i] = chars->values[i];
980 		else
981 			chp->cmg_chars.values[i] = 0;
982 	}
983 }
984 
985 int chsc_get_channel_measurement_chars(struct channel_path *chp)
986 {
987 	unsigned long flags;
988 	int ccode, ret;
989 
990 	struct {
991 		struct chsc_header request;
992 		u32 : 24;
993 		u32 first_chpid : 8;
994 		u32 : 24;
995 		u32 last_chpid : 8;
996 		u32 zeroes1;
997 		struct chsc_header response;
998 		u32 zeroes2;
999 		u32 not_valid : 1;
1000 		u32 shared : 1;
1001 		u32 : 22;
1002 		u32 chpid : 8;
1003 		u32 cmcv : 5;
1004 		u32 : 11;
1005 		u32 cmgq : 8;
1006 		u32 cmg : 8;
1007 		u32 zeroes3;
1008 		u32 data[NR_MEASUREMENT_CHARS];
1009 	} __attribute__ ((packed)) *scmc_area;
1010 
1011 	chp->shared = -1;
1012 	chp->cmg = -1;
1013 
1014 	if (!css_chsc_characteristics.scmc || !css_chsc_characteristics.secm)
1015 		return -EINVAL;
1016 
1017 	spin_lock_irqsave(&chsc_page_lock, flags);
1018 	memset(chsc_page, 0, PAGE_SIZE);
1019 	scmc_area = chsc_page;
1020 	scmc_area->request.length = 0x0010;
1021 	scmc_area->request.code = 0x0022;
1022 	scmc_area->first_chpid = chp->chpid.id;
1023 	scmc_area->last_chpid = chp->chpid.id;
1024 
1025 	ccode = chsc(scmc_area);
1026 	if (ccode > 0) {
1027 		ret = (ccode == 3) ? -ENODEV : -EBUSY;
1028 		goto out;
1029 	}
1030 
1031 	ret = chsc_error_from_response(scmc_area->response.code);
1032 	if (ret) {
1033 		CIO_CRW_EVENT(2, "chsc: scmc failed (rc=%04x)\n",
1034 			      scmc_area->response.code);
1035 		goto out;
1036 	}
1037 	if (scmc_area->not_valid)
1038 		goto out;
1039 
1040 	chp->cmg = scmc_area->cmg;
1041 	chp->shared = scmc_area->shared;
1042 	if (chp->cmg != 2 && chp->cmg != 3) {
1043 		/* No cmg-dependent data. */
1044 		goto out;
1045 	}
1046 	chsc_initialize_cmg_chars(chp, scmc_area->cmcv,
1047 				  (struct cmg_chars *) &scmc_area->data);
1048 out:
1049 	spin_unlock_irqrestore(&chsc_page_lock, flags);
1050 	return ret;
1051 }
1052 
1053 int __init chsc_init(void)
1054 {
1055 	int ret;
1056 
1057 	sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1058 	chsc_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1059 	if (!sei_page || !chsc_page) {
1060 		ret = -ENOMEM;
1061 		goto out_err;
1062 	}
1063 	ret = crw_register_handler(CRW_RSC_CSS, chsc_process_crw);
1064 	if (ret)
1065 		goto out_err;
1066 	return ret;
1067 out_err:
1068 	free_page((unsigned long)chsc_page);
1069 	free_page((unsigned long)sei_page);
1070 	return ret;
1071 }
1072 
1073 void __init chsc_init_cleanup(void)
1074 {
1075 	crw_unregister_handler(CRW_RSC_CSS);
1076 	free_page((unsigned long)chsc_page);
1077 	free_page((unsigned long)sei_page);
1078 }
1079 
1080 int __chsc_enable_facility(struct chsc_sda_area *sda_area, int operation_code)
1081 {
1082 	int ret;
1083 
1084 	sda_area->request.length = 0x0400;
1085 	sda_area->request.code = 0x0031;
1086 	sda_area->operation_code = operation_code;
1087 
1088 	ret = chsc(sda_area);
1089 	if (ret > 0) {
1090 		ret = (ret == 3) ? -ENODEV : -EBUSY;
1091 		goto out;
1092 	}
1093 
1094 	switch (sda_area->response.code) {
1095 	case 0x0101:
1096 		ret = -EOPNOTSUPP;
1097 		break;
1098 	default:
1099 		ret = chsc_error_from_response(sda_area->response.code);
1100 	}
1101 out:
1102 	return ret;
1103 }
1104 
1105 int chsc_enable_facility(int operation_code)
1106 {
1107 	struct chsc_sda_area *sda_area;
1108 	unsigned long flags;
1109 	int ret;
1110 
1111 	spin_lock_irqsave(&chsc_page_lock, flags);
1112 	memset(chsc_page, 0, PAGE_SIZE);
1113 	sda_area = chsc_page;
1114 
1115 	ret = __chsc_enable_facility(sda_area, operation_code);
1116 	if (ret != 0)
1117 		CIO_CRW_EVENT(2, "chsc: sda (oc=%x) failed (rc=%04x)\n",
1118 			      operation_code, sda_area->response.code);
1119 
1120 	spin_unlock_irqrestore(&chsc_page_lock, flags);
1121 	return ret;
1122 }
1123 
1124 int __init chsc_get_cssid(int idx)
1125 {
1126 	struct {
1127 		struct chsc_header request;
1128 		u8 atype;
1129 		u32 : 24;
1130 		u32 reserved1[6];
1131 		struct chsc_header response;
1132 		u32 reserved2[3];
1133 		struct {
1134 			u8 cssid;
1135 			u32 : 24;
1136 		} list[0];
1137 	} __packed *sdcal_area;
1138 	int ret;
1139 
1140 	spin_lock_irq(&chsc_page_lock);
1141 	memset(chsc_page, 0, PAGE_SIZE);
1142 	sdcal_area = chsc_page;
1143 	sdcal_area->request.length = 0x0020;
1144 	sdcal_area->request.code = 0x0034;
1145 	sdcal_area->atype = 4;
1146 
1147 	ret = chsc(sdcal_area);
1148 	if (ret) {
1149 		ret = (ret == 3) ? -ENODEV : -EBUSY;
1150 		goto exit;
1151 	}
1152 
1153 	ret = chsc_error_from_response(sdcal_area->response.code);
1154 	if (ret) {
1155 		CIO_CRW_EVENT(2, "chsc: sdcal failed (rc=%04x)\n",
1156 			      sdcal_area->response.code);
1157 		goto exit;
1158 	}
1159 
1160 	if ((addr_t) &sdcal_area->list[idx] <
1161 	    (addr_t) &sdcal_area->response + sdcal_area->response.length)
1162 		ret = sdcal_area->list[idx].cssid;
1163 	else
1164 		ret = -ENODEV;
1165 exit:
1166 	spin_unlock_irq(&chsc_page_lock);
1167 	return ret;
1168 }
1169 
1170 struct css_general_char css_general_characteristics;
1171 struct css_chsc_char css_chsc_characteristics;
1172 
1173 int __init
1174 chsc_determine_css_characteristics(void)
1175 {
1176 	unsigned long flags;
1177 	int result;
1178 	struct {
1179 		struct chsc_header request;
1180 		u32 reserved1;
1181 		u32 reserved2;
1182 		u32 reserved3;
1183 		struct chsc_header response;
1184 		u32 reserved4;
1185 		u32 general_char[510];
1186 		u32 chsc_char[508];
1187 	} __attribute__ ((packed)) *scsc_area;
1188 
1189 	spin_lock_irqsave(&chsc_page_lock, flags);
1190 	memset(chsc_page, 0, PAGE_SIZE);
1191 	scsc_area = chsc_page;
1192 	scsc_area->request.length = 0x0010;
1193 	scsc_area->request.code = 0x0010;
1194 
1195 	result = chsc(scsc_area);
1196 	if (result) {
1197 		result = (result == 3) ? -ENODEV : -EBUSY;
1198 		goto exit;
1199 	}
1200 
1201 	result = chsc_error_from_response(scsc_area->response.code);
1202 	if (result == 0) {
1203 		memcpy(&css_general_characteristics, scsc_area->general_char,
1204 		       sizeof(css_general_characteristics));
1205 		memcpy(&css_chsc_characteristics, scsc_area->chsc_char,
1206 		       sizeof(css_chsc_characteristics));
1207 	} else
1208 		CIO_CRW_EVENT(2, "chsc: scsc failed (rc=%04x)\n",
1209 			      scsc_area->response.code);
1210 exit:
1211 	spin_unlock_irqrestore(&chsc_page_lock, flags);
1212 	return result;
1213 }
1214 
1215 EXPORT_SYMBOL_GPL(css_general_characteristics);
1216 EXPORT_SYMBOL_GPL(css_chsc_characteristics);
1217 
1218 int chsc_sstpc(void *page, unsigned int op, u16 ctrl, u64 *clock_delta)
1219 {
1220 	struct {
1221 		struct chsc_header request;
1222 		unsigned int rsvd0;
1223 		unsigned int op : 8;
1224 		unsigned int rsvd1 : 8;
1225 		unsigned int ctrl : 16;
1226 		unsigned int rsvd2[5];
1227 		struct chsc_header response;
1228 		unsigned int rsvd3[3];
1229 		u64 clock_delta;
1230 		unsigned int rsvd4[2];
1231 	} __attribute__ ((packed)) *rr;
1232 	int rc;
1233 
1234 	memset(page, 0, PAGE_SIZE);
1235 	rr = page;
1236 	rr->request.length = 0x0020;
1237 	rr->request.code = 0x0033;
1238 	rr->op = op;
1239 	rr->ctrl = ctrl;
1240 	rc = chsc(rr);
1241 	if (rc)
1242 		return -EIO;
1243 	rc = (rr->response.code == 0x0001) ? 0 : -EIO;
1244 	if (clock_delta)
1245 		*clock_delta = rr->clock_delta;
1246 	return rc;
1247 }
1248 
1249 int chsc_sstpi(void *page, void *result, size_t size)
1250 {
1251 	struct {
1252 		struct chsc_header request;
1253 		unsigned int rsvd0[3];
1254 		struct chsc_header response;
1255 		char data[];
1256 	} __attribute__ ((packed)) *rr;
1257 	int rc;
1258 
1259 	memset(page, 0, PAGE_SIZE);
1260 	rr = page;
1261 	rr->request.length = 0x0010;
1262 	rr->request.code = 0x0038;
1263 	rc = chsc(rr);
1264 	if (rc)
1265 		return -EIO;
1266 	memcpy(result, &rr->data, size);
1267 	return (rr->response.code == 0x0001) ? 0 : -EIO;
1268 }
1269 
1270 int chsc_siosl(struct subchannel_id schid)
1271 {
1272 	struct {
1273 		struct chsc_header request;
1274 		u32 word1;
1275 		struct subchannel_id sid;
1276 		u32 word3;
1277 		struct chsc_header response;
1278 		u32 word[11];
1279 	} __attribute__ ((packed)) *siosl_area;
1280 	unsigned long flags;
1281 	int ccode;
1282 	int rc;
1283 
1284 	spin_lock_irqsave(&chsc_page_lock, flags);
1285 	memset(chsc_page, 0, PAGE_SIZE);
1286 	siosl_area = chsc_page;
1287 	siosl_area->request.length = 0x0010;
1288 	siosl_area->request.code = 0x0046;
1289 	siosl_area->word1 = 0x80000000;
1290 	siosl_area->sid = schid;
1291 
1292 	ccode = chsc(siosl_area);
1293 	if (ccode > 0) {
1294 		if (ccode == 3)
1295 			rc = -ENODEV;
1296 		else
1297 			rc = -EBUSY;
1298 		CIO_MSG_EVENT(2, "chsc: chsc failed for 0.%x.%04x (ccode=%d)\n",
1299 			      schid.ssid, schid.sch_no, ccode);
1300 		goto out;
1301 	}
1302 	rc = chsc_error_from_response(siosl_area->response.code);
1303 	if (rc)
1304 		CIO_MSG_EVENT(2, "chsc: siosl failed for 0.%x.%04x (rc=%04x)\n",
1305 			      schid.ssid, schid.sch_no,
1306 			      siosl_area->response.code);
1307 	else
1308 		CIO_MSG_EVENT(4, "chsc: siosl succeeded for 0.%x.%04x\n",
1309 			      schid.ssid, schid.sch_no);
1310 out:
1311 	spin_unlock_irqrestore(&chsc_page_lock, flags);
1312 	return rc;
1313 }
1314 EXPORT_SYMBOL_GPL(chsc_siosl);
1315 
1316 /**
1317  * chsc_scm_info() - store SCM information (SSI)
1318  * @scm_area: request and response block for SSI
1319  * @token: continuation token
1320  *
1321  * Returns 0 on success.
1322  */
1323 int chsc_scm_info(struct chsc_scm_info *scm_area, u64 token)
1324 {
1325 	int ccode, ret;
1326 
1327 	memset(scm_area, 0, sizeof(*scm_area));
1328 	scm_area->request.length = 0x0020;
1329 	scm_area->request.code = 0x004C;
1330 	scm_area->reqtok = token;
1331 
1332 	ccode = chsc(scm_area);
1333 	if (ccode > 0) {
1334 		ret = (ccode == 3) ? -ENODEV : -EBUSY;
1335 		goto out;
1336 	}
1337 	ret = chsc_error_from_response(scm_area->response.code);
1338 	if (ret != 0)
1339 		CIO_MSG_EVENT(2, "chsc: scm info failed (rc=%04x)\n",
1340 			      scm_area->response.code);
1341 out:
1342 	return ret;
1343 }
1344 EXPORT_SYMBOL_GPL(chsc_scm_info);
1345 
1346 /**
1347  * chsc_pnso_brinfo() - Perform Network-Subchannel Operation, Bridge Info.
1348  * @schid:		id of the subchannel on which PNSO is performed
1349  * @brinfo_area:	request and response block for the operation
1350  * @resume_token:	resume token for multiblock response
1351  * @cnc:		Boolean change-notification control
1352  *
1353  * brinfo_area must be allocated by the caller with get_zeroed_page(GFP_KERNEL)
1354  *
1355  * Returns 0 on success.
1356  */
1357 int chsc_pnso_brinfo(struct subchannel_id schid,
1358 		struct chsc_pnso_area *brinfo_area,
1359 		struct chsc_brinfo_resume_token resume_token,
1360 		int cnc)
1361 {
1362 	memset(brinfo_area, 0, sizeof(*brinfo_area));
1363 	brinfo_area->request.length = 0x0030;
1364 	brinfo_area->request.code = 0x003d; /* network-subchannel operation */
1365 	brinfo_area->m	   = schid.m;
1366 	brinfo_area->ssid  = schid.ssid;
1367 	brinfo_area->sch   = schid.sch_no;
1368 	brinfo_area->cssid = schid.cssid;
1369 	brinfo_area->oc    = 0; /* Store-network-bridging-information list */
1370 	brinfo_area->resume_token = resume_token;
1371 	brinfo_area->n	   = (cnc != 0);
1372 	if (chsc(brinfo_area))
1373 		return -EIO;
1374 	return chsc_error_from_response(brinfo_area->response.code);
1375 }
1376 EXPORT_SYMBOL_GPL(chsc_pnso_brinfo);
1377