xref: /openbmc/linux/drivers/s390/cio/chsc.c (revision b9b77222)
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 channel_path *chp;
456 	struct chp_link link;
457 	struct chp_id chpid;
458 	int status;
459 
460 	CIO_CRW_EVENT(4, "chsc: resource accessibility event (rs=%02x, "
461 		      "rs_id=%04x)\n", sei_area->rs, sei_area->rsid);
462 	if (sei_area->rs != 4)
463 		return;
464 	chp_id_init(&chpid);
465 	chpid.id = sei_area->rsid;
466 	/* allocate a new channel path structure, if needed */
467 	status = chp_get_status(chpid);
468 	if (!status)
469 		return;
470 
471 	if (status < 0) {
472 		chp_new(chpid);
473 	} else {
474 		chp = chpid_to_chp(chpid);
475 		mutex_lock(&chp->lock);
476 		chp_update_desc(chp);
477 		mutex_unlock(&chp->lock);
478 	}
479 	memset(&link, 0, sizeof(struct chp_link));
480 	link.chpid = chpid;
481 	if ((sei_area->vf & 0xc0) != 0) {
482 		link.fla = sei_area->fla;
483 		if ((sei_area->vf & 0xc0) == 0xc0)
484 			/* full link address */
485 			link.fla_mask = 0xffff;
486 		else
487 			/* link address */
488 			link.fla_mask = 0xff00;
489 	}
490 	s390_process_res_acc(&link);
491 }
492 
493 static void chsc_process_sei_chp_avail(struct chsc_sei_nt0_area *sei_area)
494 {
495 	struct channel_path *chp;
496 	struct chp_id chpid;
497 	u8 *data;
498 	int num;
499 
500 	CIO_CRW_EVENT(4, "chsc: channel path availability information\n");
501 	if (sei_area->rs != 0)
502 		return;
503 	data = sei_area->ccdf;
504 	chp_id_init(&chpid);
505 	for (num = 0; num <= __MAX_CHPID; num++) {
506 		if (!chp_test_bit(data, num))
507 			continue;
508 		chpid.id = num;
509 
510 		CIO_CRW_EVENT(4, "Update information for channel path "
511 			      "%x.%02x\n", chpid.cssid, chpid.id);
512 		chp = chpid_to_chp(chpid);
513 		if (!chp) {
514 			chp_new(chpid);
515 			continue;
516 		}
517 		mutex_lock(&chp->lock);
518 		chp_update_desc(chp);
519 		mutex_unlock(&chp->lock);
520 	}
521 }
522 
523 struct chp_config_data {
524 	u8 map[32];
525 	u8 op;
526 	u8 pc;
527 };
528 
529 static void chsc_process_sei_chp_config(struct chsc_sei_nt0_area *sei_area)
530 {
531 	struct chp_config_data *data;
532 	struct chp_id chpid;
533 	int num;
534 	char *events[3] = {"configure", "deconfigure", "cancel deconfigure"};
535 
536 	CIO_CRW_EVENT(4, "chsc: channel-path-configuration notification\n");
537 	if (sei_area->rs != 0)
538 		return;
539 	data = (struct chp_config_data *) &(sei_area->ccdf);
540 	chp_id_init(&chpid);
541 	for (num = 0; num <= __MAX_CHPID; num++) {
542 		if (!chp_test_bit(data->map, num))
543 			continue;
544 		chpid.id = num;
545 		pr_notice("Processing %s for channel path %x.%02x\n",
546 			  events[data->op], chpid.cssid, chpid.id);
547 		switch (data->op) {
548 		case 0:
549 			chp_cfg_schedule(chpid, 1);
550 			break;
551 		case 1:
552 			chp_cfg_schedule(chpid, 0);
553 			break;
554 		case 2:
555 			chp_cfg_cancel_deconfigure(chpid);
556 			break;
557 		}
558 	}
559 }
560 
561 static void chsc_process_sei_scm_change(struct chsc_sei_nt0_area *sei_area)
562 {
563 	int ret;
564 
565 	CIO_CRW_EVENT(4, "chsc: scm change notification\n");
566 	if (sei_area->rs != 7)
567 		return;
568 
569 	ret = scm_update_information();
570 	if (ret)
571 		CIO_CRW_EVENT(0, "chsc: updating change notification"
572 			      " failed (rc=%d).\n", ret);
573 }
574 
575 static void chsc_process_sei_scm_avail(struct chsc_sei_nt0_area *sei_area)
576 {
577 	int ret;
578 
579 	CIO_CRW_EVENT(4, "chsc: scm available information\n");
580 	if (sei_area->rs != 7)
581 		return;
582 
583 	ret = scm_process_availability_information();
584 	if (ret)
585 		CIO_CRW_EVENT(0, "chsc: process availability information"
586 			      " failed (rc=%d).\n", ret);
587 }
588 
589 static void chsc_process_sei_nt2(struct chsc_sei_nt2_area *sei_area)
590 {
591 	switch (sei_area->cc) {
592 	case 1:
593 		zpci_event_error(sei_area->ccdf);
594 		break;
595 	case 2:
596 		zpci_event_availability(sei_area->ccdf);
597 		break;
598 	default:
599 		CIO_CRW_EVENT(2, "chsc: sei nt2 unhandled cc=%d\n",
600 			      sei_area->cc);
601 		break;
602 	}
603 }
604 
605 static void chsc_process_sei_nt0(struct chsc_sei_nt0_area *sei_area)
606 {
607 	/* which kind of information was stored? */
608 	switch (sei_area->cc) {
609 	case 1: /* link incident*/
610 		chsc_process_sei_link_incident(sei_area);
611 		break;
612 	case 2: /* i/o resource accessibility */
613 		chsc_process_sei_res_acc(sei_area);
614 		break;
615 	case 7: /* channel-path-availability information */
616 		chsc_process_sei_chp_avail(sei_area);
617 		break;
618 	case 8: /* channel-path-configuration notification */
619 		chsc_process_sei_chp_config(sei_area);
620 		break;
621 	case 12: /* scm change notification */
622 		chsc_process_sei_scm_change(sei_area);
623 		break;
624 	case 14: /* scm available notification */
625 		chsc_process_sei_scm_avail(sei_area);
626 		break;
627 	default: /* other stuff */
628 		CIO_CRW_EVENT(2, "chsc: sei nt0 unhandled cc=%d\n",
629 			      sei_area->cc);
630 		break;
631 	}
632 
633 	/* Check if we might have lost some information. */
634 	if (sei_area->flags & 0x40) {
635 		CIO_CRW_EVENT(2, "chsc: event overflow\n");
636 		css_schedule_eval_all();
637 	}
638 }
639 
640 static void chsc_process_event_information(struct chsc_sei *sei, u64 ntsm)
641 {
642 	static int ntsm_unsupported;
643 
644 	while (true) {
645 		memset(sei, 0, sizeof(*sei));
646 		sei->request.length = 0x0010;
647 		sei->request.code = 0x000e;
648 		if (!ntsm_unsupported)
649 			sei->ntsm = ntsm;
650 
651 		if (chsc(sei))
652 			break;
653 
654 		if (sei->response.code != 0x0001) {
655 			CIO_CRW_EVENT(2, "chsc: sei failed (rc=%04x, ntsm=%llx)\n",
656 				      sei->response.code, sei->ntsm);
657 
658 			if (sei->response.code == 3 && sei->ntsm) {
659 				/* Fallback for old firmware. */
660 				ntsm_unsupported = 1;
661 				continue;
662 			}
663 			break;
664 		}
665 
666 		CIO_CRW_EVENT(2, "chsc: sei successful (nt=%d)\n", sei->nt);
667 		switch (sei->nt) {
668 		case 0:
669 			chsc_process_sei_nt0(&sei->u.nt0_area);
670 			break;
671 		case 2:
672 			chsc_process_sei_nt2(&sei->u.nt2_area);
673 			break;
674 		default:
675 			CIO_CRW_EVENT(2, "chsc: unhandled nt: %d\n", sei->nt);
676 			break;
677 		}
678 
679 		if (!(sei->u.nt0_area.flags & 0x80))
680 			break;
681 	}
682 }
683 
684 /*
685  * Handle channel subsystem related CRWs.
686  * Use store event information to find out what's going on.
687  *
688  * Note: Access to sei_page is serialized through machine check handler
689  * thread, so no need for locking.
690  */
691 static void chsc_process_crw(struct crw *crw0, struct crw *crw1, int overflow)
692 {
693 	struct chsc_sei *sei = sei_page;
694 
695 	if (overflow) {
696 		css_schedule_eval_all();
697 		return;
698 	}
699 	CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, "
700 		      "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
701 		      crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
702 		      crw0->erc, crw0->rsid);
703 
704 	CIO_TRACE_EVENT(2, "prcss");
705 	chsc_process_event_information(sei, CHSC_SEI_NT0 | CHSC_SEI_NT2);
706 }
707 
708 void chsc_chp_online(struct chp_id chpid)
709 {
710 	struct channel_path *chp = chpid_to_chp(chpid);
711 	struct chp_link link;
712 	char dbf_txt[15];
713 
714 	sprintf(dbf_txt, "cadd%x.%02x", chpid.cssid, chpid.id);
715 	CIO_TRACE_EVENT(2, dbf_txt);
716 
717 	if (chp_get_status(chpid) != 0) {
718 		memset(&link, 0, sizeof(struct chp_link));
719 		link.chpid = chpid;
720 		/* Wait until previous actions have settled. */
721 		css_wait_for_slow_path();
722 
723 		mutex_lock(&chp->lock);
724 		chp_update_desc(chp);
725 		mutex_unlock(&chp->lock);
726 
727 		for_each_subchannel_staged(__s390_process_res_acc, NULL,
728 					   &link);
729 		css_schedule_reprobe();
730 	}
731 }
732 
733 static void __s390_subchannel_vary_chpid(struct subchannel *sch,
734 					 struct chp_id chpid, int on)
735 {
736 	unsigned long flags;
737 	struct chp_link link;
738 
739 	memset(&link, 0, sizeof(struct chp_link));
740 	link.chpid = chpid;
741 	spin_lock_irqsave(sch->lock, flags);
742 	if (sch->driver && sch->driver->chp_event)
743 		sch->driver->chp_event(sch, &link,
744 				       on ? CHP_VARY_ON : CHP_VARY_OFF);
745 	spin_unlock_irqrestore(sch->lock, flags);
746 }
747 
748 static int s390_subchannel_vary_chpid_off(struct subchannel *sch, void *data)
749 {
750 	struct chp_id *chpid = data;
751 
752 	__s390_subchannel_vary_chpid(sch, *chpid, 0);
753 	return 0;
754 }
755 
756 static int s390_subchannel_vary_chpid_on(struct subchannel *sch, void *data)
757 {
758 	struct chp_id *chpid = data;
759 
760 	__s390_subchannel_vary_chpid(sch, *chpid, 1);
761 	return 0;
762 }
763 
764 /**
765  * chsc_chp_vary - propagate channel-path vary operation to subchannels
766  * @chpid: channl-path ID
767  * @on: non-zero for vary online, zero for vary offline
768  */
769 int chsc_chp_vary(struct chp_id chpid, int on)
770 {
771 	struct channel_path *chp = chpid_to_chp(chpid);
772 
773 	/* Wait until previous actions have settled. */
774 	css_wait_for_slow_path();
775 	/*
776 	 * Redo PathVerification on the devices the chpid connects to
777 	 */
778 	if (on) {
779 		/* Try to update the channel path description. */
780 		chp_update_desc(chp);
781 		for_each_subchannel_staged(s390_subchannel_vary_chpid_on,
782 					   NULL, &chpid);
783 		css_schedule_reprobe();
784 	} else
785 		for_each_subchannel_staged(s390_subchannel_vary_chpid_off,
786 					   NULL, &chpid);
787 
788 	return 0;
789 }
790 
791 static void
792 chsc_remove_cmg_attr(struct channel_subsystem *css)
793 {
794 	int i;
795 
796 	for (i = 0; i <= __MAX_CHPID; i++) {
797 		if (!css->chps[i])
798 			continue;
799 		chp_remove_cmg_attr(css->chps[i]);
800 	}
801 }
802 
803 static int
804 chsc_add_cmg_attr(struct channel_subsystem *css)
805 {
806 	int i, ret;
807 
808 	ret = 0;
809 	for (i = 0; i <= __MAX_CHPID; i++) {
810 		if (!css->chps[i])
811 			continue;
812 		ret = chp_add_cmg_attr(css->chps[i]);
813 		if (ret)
814 			goto cleanup;
815 	}
816 	return ret;
817 cleanup:
818 	for (--i; i >= 0; i--) {
819 		if (!css->chps[i])
820 			continue;
821 		chp_remove_cmg_attr(css->chps[i]);
822 	}
823 	return ret;
824 }
825 
826 int __chsc_do_secm(struct channel_subsystem *css, int enable)
827 {
828 	struct {
829 		struct chsc_header request;
830 		u32 operation_code : 2;
831 		u32 : 30;
832 		u32 key : 4;
833 		u32 : 28;
834 		u32 zeroes1;
835 		u32 cub_addr1;
836 		u32 zeroes2;
837 		u32 cub_addr2;
838 		u32 reserved[13];
839 		struct chsc_header response;
840 		u32 status : 8;
841 		u32 : 4;
842 		u32 fmt : 4;
843 		u32 : 16;
844 	} __attribute__ ((packed)) *secm_area;
845 	unsigned long flags;
846 	int ret, ccode;
847 
848 	spin_lock_irqsave(&chsc_page_lock, flags);
849 	memset(chsc_page, 0, PAGE_SIZE);
850 	secm_area = chsc_page;
851 	secm_area->request.length = 0x0050;
852 	secm_area->request.code = 0x0016;
853 
854 	secm_area->key = PAGE_DEFAULT_KEY >> 4;
855 	secm_area->cub_addr1 = (u64)(unsigned long)css->cub_addr1;
856 	secm_area->cub_addr2 = (u64)(unsigned long)css->cub_addr2;
857 
858 	secm_area->operation_code = enable ? 0 : 1;
859 
860 	ccode = chsc(secm_area);
861 	if (ccode > 0) {
862 		ret = (ccode == 3) ? -ENODEV : -EBUSY;
863 		goto out;
864 	}
865 
866 	switch (secm_area->response.code) {
867 	case 0x0102:
868 	case 0x0103:
869 		ret = -EINVAL;
870 		break;
871 	default:
872 		ret = chsc_error_from_response(secm_area->response.code);
873 	}
874 	if (ret != 0)
875 		CIO_CRW_EVENT(2, "chsc: secm failed (rc=%04x)\n",
876 			      secm_area->response.code);
877 out:
878 	spin_unlock_irqrestore(&chsc_page_lock, flags);
879 	return ret;
880 }
881 
882 int
883 chsc_secm(struct channel_subsystem *css, int enable)
884 {
885 	int ret;
886 
887 	if (enable && !css->cm_enabled) {
888 		css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
889 		css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
890 		if (!css->cub_addr1 || !css->cub_addr2) {
891 			free_page((unsigned long)css->cub_addr1);
892 			free_page((unsigned long)css->cub_addr2);
893 			return -ENOMEM;
894 		}
895 	}
896 	ret = __chsc_do_secm(css, enable);
897 	if (!ret) {
898 		css->cm_enabled = enable;
899 		if (css->cm_enabled) {
900 			ret = chsc_add_cmg_attr(css);
901 			if (ret) {
902 				__chsc_do_secm(css, 0);
903 				css->cm_enabled = 0;
904 			}
905 		} else
906 			chsc_remove_cmg_attr(css);
907 	}
908 	if (!css->cm_enabled) {
909 		free_page((unsigned long)css->cub_addr1);
910 		free_page((unsigned long)css->cub_addr2);
911 	}
912 	return ret;
913 }
914 
915 int chsc_determine_channel_path_desc(struct chp_id chpid, int fmt, int rfmt,
916 				     int c, int m, void *page)
917 {
918 	struct chsc_scpd *scpd_area;
919 	int ccode, ret;
920 
921 	if ((rfmt == 1 || rfmt == 0) && c == 1 &&
922 	    !css_general_characteristics.fcs)
923 		return -EINVAL;
924 	if ((rfmt == 2) && !css_general_characteristics.cib)
925 		return -EINVAL;
926 	if ((rfmt == 3) && !css_general_characteristics.util_str)
927 		return -EINVAL;
928 
929 	memset(page, 0, PAGE_SIZE);
930 	scpd_area = page;
931 	scpd_area->request.length = 0x0010;
932 	scpd_area->request.code = 0x0002;
933 	scpd_area->cssid = chpid.cssid;
934 	scpd_area->first_chpid = chpid.id;
935 	scpd_area->last_chpid = chpid.id;
936 	scpd_area->m = m;
937 	scpd_area->c = c;
938 	scpd_area->fmt = fmt;
939 	scpd_area->rfmt = rfmt;
940 
941 	ccode = chsc(scpd_area);
942 	if (ccode > 0)
943 		return (ccode == 3) ? -ENODEV : -EBUSY;
944 
945 	ret = chsc_error_from_response(scpd_area->response.code);
946 	if (ret)
947 		CIO_CRW_EVENT(2, "chsc: scpd failed (rc=%04x)\n",
948 			      scpd_area->response.code);
949 	return ret;
950 }
951 EXPORT_SYMBOL_GPL(chsc_determine_channel_path_desc);
952 
953 #define chsc_det_chp_desc(FMT, c)					\
954 int chsc_determine_fmt##FMT##_channel_path_desc(			\
955 	struct chp_id chpid, struct channel_path_desc_fmt##FMT *desc)	\
956 {									\
957 	struct chsc_scpd *scpd_area;					\
958 	unsigned long flags;						\
959 	int ret;							\
960 									\
961 	spin_lock_irqsave(&chsc_page_lock, flags);			\
962 	scpd_area = chsc_page;						\
963 	ret = chsc_determine_channel_path_desc(chpid, 0, FMT, c, 0,	\
964 					       scpd_area);		\
965 	if (ret)							\
966 		goto out;						\
967 									\
968 	memcpy(desc, scpd_area->data, sizeof(*desc));			\
969 out:									\
970 	spin_unlock_irqrestore(&chsc_page_lock, flags);			\
971 	return ret;							\
972 }
973 
974 chsc_det_chp_desc(0, 0)
975 chsc_det_chp_desc(1, 1)
976 chsc_det_chp_desc(3, 0)
977 
978 static void
979 chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
980 			  struct cmg_chars *chars)
981 {
982 	int i, mask;
983 
984 	for (i = 0; i < NR_MEASUREMENT_CHARS; i++) {
985 		mask = 0x80 >> (i + 3);
986 		if (cmcv & mask)
987 			chp->cmg_chars.values[i] = chars->values[i];
988 		else
989 			chp->cmg_chars.values[i] = 0;
990 	}
991 }
992 
993 int chsc_get_channel_measurement_chars(struct channel_path *chp)
994 {
995 	unsigned long flags;
996 	int ccode, ret;
997 
998 	struct {
999 		struct chsc_header request;
1000 		u32 : 24;
1001 		u32 first_chpid : 8;
1002 		u32 : 24;
1003 		u32 last_chpid : 8;
1004 		u32 zeroes1;
1005 		struct chsc_header response;
1006 		u32 zeroes2;
1007 		u32 not_valid : 1;
1008 		u32 shared : 1;
1009 		u32 : 22;
1010 		u32 chpid : 8;
1011 		u32 cmcv : 5;
1012 		u32 : 11;
1013 		u32 cmgq : 8;
1014 		u32 cmg : 8;
1015 		u32 zeroes3;
1016 		u32 data[NR_MEASUREMENT_CHARS];
1017 	} __attribute__ ((packed)) *scmc_area;
1018 
1019 	chp->shared = -1;
1020 	chp->cmg = -1;
1021 
1022 	if (!css_chsc_characteristics.scmc || !css_chsc_characteristics.secm)
1023 		return -EINVAL;
1024 
1025 	spin_lock_irqsave(&chsc_page_lock, flags);
1026 	memset(chsc_page, 0, PAGE_SIZE);
1027 	scmc_area = chsc_page;
1028 	scmc_area->request.length = 0x0010;
1029 	scmc_area->request.code = 0x0022;
1030 	scmc_area->first_chpid = chp->chpid.id;
1031 	scmc_area->last_chpid = chp->chpid.id;
1032 
1033 	ccode = chsc(scmc_area);
1034 	if (ccode > 0) {
1035 		ret = (ccode == 3) ? -ENODEV : -EBUSY;
1036 		goto out;
1037 	}
1038 
1039 	ret = chsc_error_from_response(scmc_area->response.code);
1040 	if (ret) {
1041 		CIO_CRW_EVENT(2, "chsc: scmc failed (rc=%04x)\n",
1042 			      scmc_area->response.code);
1043 		goto out;
1044 	}
1045 	if (scmc_area->not_valid)
1046 		goto out;
1047 
1048 	chp->cmg = scmc_area->cmg;
1049 	chp->shared = scmc_area->shared;
1050 	if (chp->cmg != 2 && chp->cmg != 3) {
1051 		/* No cmg-dependent data. */
1052 		goto out;
1053 	}
1054 	chsc_initialize_cmg_chars(chp, scmc_area->cmcv,
1055 				  (struct cmg_chars *) &scmc_area->data);
1056 out:
1057 	spin_unlock_irqrestore(&chsc_page_lock, flags);
1058 	return ret;
1059 }
1060 
1061 int __init chsc_init(void)
1062 {
1063 	int ret;
1064 
1065 	sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1066 	chsc_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
1067 	if (!sei_page || !chsc_page) {
1068 		ret = -ENOMEM;
1069 		goto out_err;
1070 	}
1071 	ret = crw_register_handler(CRW_RSC_CSS, chsc_process_crw);
1072 	if (ret)
1073 		goto out_err;
1074 	return ret;
1075 out_err:
1076 	free_page((unsigned long)chsc_page);
1077 	free_page((unsigned long)sei_page);
1078 	return ret;
1079 }
1080 
1081 void __init chsc_init_cleanup(void)
1082 {
1083 	crw_unregister_handler(CRW_RSC_CSS);
1084 	free_page((unsigned long)chsc_page);
1085 	free_page((unsigned long)sei_page);
1086 }
1087 
1088 int __chsc_enable_facility(struct chsc_sda_area *sda_area, int operation_code)
1089 {
1090 	int ret;
1091 
1092 	sda_area->request.length = 0x0400;
1093 	sda_area->request.code = 0x0031;
1094 	sda_area->operation_code = operation_code;
1095 
1096 	ret = chsc(sda_area);
1097 	if (ret > 0) {
1098 		ret = (ret == 3) ? -ENODEV : -EBUSY;
1099 		goto out;
1100 	}
1101 
1102 	switch (sda_area->response.code) {
1103 	case 0x0101:
1104 		ret = -EOPNOTSUPP;
1105 		break;
1106 	default:
1107 		ret = chsc_error_from_response(sda_area->response.code);
1108 	}
1109 out:
1110 	return ret;
1111 }
1112 
1113 int chsc_enable_facility(int operation_code)
1114 {
1115 	struct chsc_sda_area *sda_area;
1116 	unsigned long flags;
1117 	int ret;
1118 
1119 	spin_lock_irqsave(&chsc_page_lock, flags);
1120 	memset(chsc_page, 0, PAGE_SIZE);
1121 	sda_area = chsc_page;
1122 
1123 	ret = __chsc_enable_facility(sda_area, operation_code);
1124 	if (ret != 0)
1125 		CIO_CRW_EVENT(2, "chsc: sda (oc=%x) failed (rc=%04x)\n",
1126 			      operation_code, sda_area->response.code);
1127 
1128 	spin_unlock_irqrestore(&chsc_page_lock, flags);
1129 	return ret;
1130 }
1131 
1132 int __init chsc_get_cssid(int idx)
1133 {
1134 	struct {
1135 		struct chsc_header request;
1136 		u8 atype;
1137 		u32 : 24;
1138 		u32 reserved1[6];
1139 		struct chsc_header response;
1140 		u32 reserved2[3];
1141 		struct {
1142 			u8 cssid;
1143 			u32 : 24;
1144 		} list[0];
1145 	} __packed *sdcal_area;
1146 	int ret;
1147 
1148 	spin_lock_irq(&chsc_page_lock);
1149 	memset(chsc_page, 0, PAGE_SIZE);
1150 	sdcal_area = chsc_page;
1151 	sdcal_area->request.length = 0x0020;
1152 	sdcal_area->request.code = 0x0034;
1153 	sdcal_area->atype = 4;
1154 
1155 	ret = chsc(sdcal_area);
1156 	if (ret) {
1157 		ret = (ret == 3) ? -ENODEV : -EBUSY;
1158 		goto exit;
1159 	}
1160 
1161 	ret = chsc_error_from_response(sdcal_area->response.code);
1162 	if (ret) {
1163 		CIO_CRW_EVENT(2, "chsc: sdcal failed (rc=%04x)\n",
1164 			      sdcal_area->response.code);
1165 		goto exit;
1166 	}
1167 
1168 	if ((addr_t) &sdcal_area->list[idx] <
1169 	    (addr_t) &sdcal_area->response + sdcal_area->response.length)
1170 		ret = sdcal_area->list[idx].cssid;
1171 	else
1172 		ret = -ENODEV;
1173 exit:
1174 	spin_unlock_irq(&chsc_page_lock);
1175 	return ret;
1176 }
1177 
1178 struct css_general_char css_general_characteristics;
1179 struct css_chsc_char css_chsc_characteristics;
1180 
1181 int __init
1182 chsc_determine_css_characteristics(void)
1183 {
1184 	unsigned long flags;
1185 	int result;
1186 	struct {
1187 		struct chsc_header request;
1188 		u32 reserved1;
1189 		u32 reserved2;
1190 		u32 reserved3;
1191 		struct chsc_header response;
1192 		u32 reserved4;
1193 		u32 general_char[510];
1194 		u32 chsc_char[508];
1195 	} __attribute__ ((packed)) *scsc_area;
1196 
1197 	spin_lock_irqsave(&chsc_page_lock, flags);
1198 	memset(chsc_page, 0, PAGE_SIZE);
1199 	scsc_area = chsc_page;
1200 	scsc_area->request.length = 0x0010;
1201 	scsc_area->request.code = 0x0010;
1202 
1203 	result = chsc(scsc_area);
1204 	if (result) {
1205 		result = (result == 3) ? -ENODEV : -EBUSY;
1206 		goto exit;
1207 	}
1208 
1209 	result = chsc_error_from_response(scsc_area->response.code);
1210 	if (result == 0) {
1211 		memcpy(&css_general_characteristics, scsc_area->general_char,
1212 		       sizeof(css_general_characteristics));
1213 		memcpy(&css_chsc_characteristics, scsc_area->chsc_char,
1214 		       sizeof(css_chsc_characteristics));
1215 	} else
1216 		CIO_CRW_EVENT(2, "chsc: scsc failed (rc=%04x)\n",
1217 			      scsc_area->response.code);
1218 exit:
1219 	spin_unlock_irqrestore(&chsc_page_lock, flags);
1220 	return result;
1221 }
1222 
1223 EXPORT_SYMBOL_GPL(css_general_characteristics);
1224 EXPORT_SYMBOL_GPL(css_chsc_characteristics);
1225 
1226 int chsc_sstpc(void *page, unsigned int op, u16 ctrl, u64 *clock_delta)
1227 {
1228 	struct {
1229 		struct chsc_header request;
1230 		unsigned int rsvd0;
1231 		unsigned int op : 8;
1232 		unsigned int rsvd1 : 8;
1233 		unsigned int ctrl : 16;
1234 		unsigned int rsvd2[5];
1235 		struct chsc_header response;
1236 		unsigned int rsvd3[3];
1237 		u64 clock_delta;
1238 		unsigned int rsvd4[2];
1239 	} __attribute__ ((packed)) *rr;
1240 	int rc;
1241 
1242 	memset(page, 0, PAGE_SIZE);
1243 	rr = page;
1244 	rr->request.length = 0x0020;
1245 	rr->request.code = 0x0033;
1246 	rr->op = op;
1247 	rr->ctrl = ctrl;
1248 	rc = chsc(rr);
1249 	if (rc)
1250 		return -EIO;
1251 	rc = (rr->response.code == 0x0001) ? 0 : -EIO;
1252 	if (clock_delta)
1253 		*clock_delta = rr->clock_delta;
1254 	return rc;
1255 }
1256 
1257 int chsc_sstpi(void *page, void *result, size_t size)
1258 {
1259 	struct {
1260 		struct chsc_header request;
1261 		unsigned int rsvd0[3];
1262 		struct chsc_header response;
1263 		char data[];
1264 	} __attribute__ ((packed)) *rr;
1265 	int rc;
1266 
1267 	memset(page, 0, PAGE_SIZE);
1268 	rr = page;
1269 	rr->request.length = 0x0010;
1270 	rr->request.code = 0x0038;
1271 	rc = chsc(rr);
1272 	if (rc)
1273 		return -EIO;
1274 	memcpy(result, &rr->data, size);
1275 	return (rr->response.code == 0x0001) ? 0 : -EIO;
1276 }
1277 
1278 int chsc_siosl(struct subchannel_id schid)
1279 {
1280 	struct {
1281 		struct chsc_header request;
1282 		u32 word1;
1283 		struct subchannel_id sid;
1284 		u32 word3;
1285 		struct chsc_header response;
1286 		u32 word[11];
1287 	} __attribute__ ((packed)) *siosl_area;
1288 	unsigned long flags;
1289 	int ccode;
1290 	int rc;
1291 
1292 	spin_lock_irqsave(&chsc_page_lock, flags);
1293 	memset(chsc_page, 0, PAGE_SIZE);
1294 	siosl_area = chsc_page;
1295 	siosl_area->request.length = 0x0010;
1296 	siosl_area->request.code = 0x0046;
1297 	siosl_area->word1 = 0x80000000;
1298 	siosl_area->sid = schid;
1299 
1300 	ccode = chsc(siosl_area);
1301 	if (ccode > 0) {
1302 		if (ccode == 3)
1303 			rc = -ENODEV;
1304 		else
1305 			rc = -EBUSY;
1306 		CIO_MSG_EVENT(2, "chsc: chsc failed for 0.%x.%04x (ccode=%d)\n",
1307 			      schid.ssid, schid.sch_no, ccode);
1308 		goto out;
1309 	}
1310 	rc = chsc_error_from_response(siosl_area->response.code);
1311 	if (rc)
1312 		CIO_MSG_EVENT(2, "chsc: siosl failed for 0.%x.%04x (rc=%04x)\n",
1313 			      schid.ssid, schid.sch_no,
1314 			      siosl_area->response.code);
1315 	else
1316 		CIO_MSG_EVENT(4, "chsc: siosl succeeded for 0.%x.%04x\n",
1317 			      schid.ssid, schid.sch_no);
1318 out:
1319 	spin_unlock_irqrestore(&chsc_page_lock, flags);
1320 	return rc;
1321 }
1322 EXPORT_SYMBOL_GPL(chsc_siosl);
1323 
1324 /**
1325  * chsc_scm_info() - store SCM information (SSI)
1326  * @scm_area: request and response block for SSI
1327  * @token: continuation token
1328  *
1329  * Returns 0 on success.
1330  */
1331 int chsc_scm_info(struct chsc_scm_info *scm_area, u64 token)
1332 {
1333 	int ccode, ret;
1334 
1335 	memset(scm_area, 0, sizeof(*scm_area));
1336 	scm_area->request.length = 0x0020;
1337 	scm_area->request.code = 0x004C;
1338 	scm_area->reqtok = token;
1339 
1340 	ccode = chsc(scm_area);
1341 	if (ccode > 0) {
1342 		ret = (ccode == 3) ? -ENODEV : -EBUSY;
1343 		goto out;
1344 	}
1345 	ret = chsc_error_from_response(scm_area->response.code);
1346 	if (ret != 0)
1347 		CIO_MSG_EVENT(2, "chsc: scm info failed (rc=%04x)\n",
1348 			      scm_area->response.code);
1349 out:
1350 	return ret;
1351 }
1352 EXPORT_SYMBOL_GPL(chsc_scm_info);
1353 
1354 /**
1355  * chsc_pnso_brinfo() - Perform Network-Subchannel Operation, Bridge Info.
1356  * @schid:		id of the subchannel on which PNSO is performed
1357  * @brinfo_area:	request and response block for the operation
1358  * @resume_token:	resume token for multiblock response
1359  * @cnc:		Boolean change-notification control
1360  *
1361  * brinfo_area must be allocated by the caller with get_zeroed_page(GFP_KERNEL)
1362  *
1363  * Returns 0 on success.
1364  */
1365 int chsc_pnso_brinfo(struct subchannel_id schid,
1366 		struct chsc_pnso_area *brinfo_area,
1367 		struct chsc_brinfo_resume_token resume_token,
1368 		int cnc)
1369 {
1370 	memset(brinfo_area, 0, sizeof(*brinfo_area));
1371 	brinfo_area->request.length = 0x0030;
1372 	brinfo_area->request.code = 0x003d; /* network-subchannel operation */
1373 	brinfo_area->m	   = schid.m;
1374 	brinfo_area->ssid  = schid.ssid;
1375 	brinfo_area->sch   = schid.sch_no;
1376 	brinfo_area->cssid = schid.cssid;
1377 	brinfo_area->oc    = 0; /* Store-network-bridging-information list */
1378 	brinfo_area->resume_token = resume_token;
1379 	brinfo_area->n	   = (cnc != 0);
1380 	if (chsc(brinfo_area))
1381 		return -EIO;
1382 	return chsc_error_from_response(brinfo_area->response.code);
1383 }
1384 EXPORT_SYMBOL_GPL(chsc_pnso_brinfo);
1385