xref: /openbmc/linux/drivers/s390/cio/chsc.c (revision 7b6d864b)
1 /*
2  *   S/390 common I/O routines -- channel subsystem call
3  *
4  *    Copyright IBM Corp. 1999,2012
5  *    Author(s): Ingo Adlung (adlung@de.ibm.com)
6  *		 Cornelia Huck (cornelia.huck@de.ibm.com)
7  *		 Arnd Bergmann (arndb@de.ibm.com)
8  */
9 
10 #define KMSG_COMPONENT "cio"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12 
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/init.h>
16 #include <linux/device.h>
17 #include <linux/pci.h>
18 
19 #include <asm/cio.h>
20 #include <asm/chpid.h>
21 #include <asm/chsc.h>
22 #include <asm/crw.h>
23 #include <asm/isc.h>
24 
25 #include "css.h"
26 #include "cio.h"
27 #include "cio_debug.h"
28 #include "ioasm.h"
29 #include "chp.h"
30 #include "chsc.h"
31 
32 static void *sei_page;
33 static void *chsc_page;
34 static DEFINE_SPINLOCK(chsc_page_lock);
35 
36 /**
37  * chsc_error_from_response() - convert a chsc response to an error
38  * @response: chsc response code
39  *
40  * Returns an appropriate Linux error code for @response.
41  */
42 int chsc_error_from_response(int response)
43 {
44 	switch (response) {
45 	case 0x0001:
46 		return 0;
47 	case 0x0002:
48 	case 0x0003:
49 	case 0x0006:
50 	case 0x0007:
51 	case 0x0008:
52 	case 0x000a:
53 	case 0x0104:
54 		return -EINVAL;
55 	case 0x0004:
56 		return -EOPNOTSUPP;
57 	case 0x000b:
58 		return -EBUSY;
59 	case 0x0100:
60 	case 0x0102:
61 		return -ENOMEM;
62 	default:
63 		return -EIO;
64 	}
65 }
66 EXPORT_SYMBOL_GPL(chsc_error_from_response);
67 
68 struct chsc_ssd_area {
69 	struct chsc_header request;
70 	u16 :10;
71 	u16 ssid:2;
72 	u16 :4;
73 	u16 f_sch;	  /* first subchannel */
74 	u16 :16;
75 	u16 l_sch;	  /* last subchannel */
76 	u32 :32;
77 	struct chsc_header response;
78 	u32 :32;
79 	u8 sch_valid : 1;
80 	u8 dev_valid : 1;
81 	u8 st	     : 3; /* subchannel type */
82 	u8 zeroes    : 3;
83 	u8  unit_addr;	  /* unit address */
84 	u16 devno;	  /* device number */
85 	u8 path_mask;
86 	u8 fla_valid_mask;
87 	u16 sch;	  /* subchannel */
88 	u8 chpid[8];	  /* chpids 0-7 */
89 	u16 fla[8];	  /* full link addresses 0-7 */
90 } __attribute__ ((packed));
91 
92 int chsc_get_ssd_info(struct subchannel_id schid, struct chsc_ssd_info *ssd)
93 {
94 	struct chsc_ssd_area *ssd_area;
95 	int ccode;
96 	int ret;
97 	int i;
98 	int mask;
99 
100 	spin_lock_irq(&chsc_page_lock);
101 	memset(chsc_page, 0, PAGE_SIZE);
102 	ssd_area = chsc_page;
103 	ssd_area->request.length = 0x0010;
104 	ssd_area->request.code = 0x0004;
105 	ssd_area->ssid = schid.ssid;
106 	ssd_area->f_sch = schid.sch_no;
107 	ssd_area->l_sch = schid.sch_no;
108 
109 	ccode = chsc(ssd_area);
110 	/* Check response. */
111 	if (ccode > 0) {
112 		ret = (ccode == 3) ? -ENODEV : -EBUSY;
113 		goto out;
114 	}
115 	ret = chsc_error_from_response(ssd_area->response.code);
116 	if (ret != 0) {
117 		CIO_MSG_EVENT(2, "chsc: ssd failed for 0.%x.%04x (rc=%04x)\n",
118 			      schid.ssid, schid.sch_no,
119 			      ssd_area->response.code);
120 		goto out;
121 	}
122 	if (!ssd_area->sch_valid) {
123 		ret = -ENODEV;
124 		goto out;
125 	}
126 	/* Copy data */
127 	ret = 0;
128 	memset(ssd, 0, sizeof(struct chsc_ssd_info));
129 	if ((ssd_area->st != SUBCHANNEL_TYPE_IO) &&
130 	    (ssd_area->st != SUBCHANNEL_TYPE_MSG))
131 		goto out;
132 	ssd->path_mask = ssd_area->path_mask;
133 	ssd->fla_valid_mask = ssd_area->fla_valid_mask;
134 	for (i = 0; i < 8; i++) {
135 		mask = 0x80 >> i;
136 		if (ssd_area->path_mask & mask) {
137 			chp_id_init(&ssd->chpid[i]);
138 			ssd->chpid[i].id = ssd_area->chpid[i];
139 		}
140 		if (ssd_area->fla_valid_mask & mask)
141 			ssd->fla[i] = ssd_area->fla[i];
142 	}
143 out:
144 	spin_unlock_irq(&chsc_page_lock);
145 	return ret;
146 }
147 
148 /**
149  * chsc_ssqd() - store subchannel QDIO data (SSQD)
150  * @schid: id of the subchannel on which SSQD is performed
151  * @ssqd: request and response block for SSQD
152  *
153  * Returns 0 on success.
154  */
155 int chsc_ssqd(struct subchannel_id schid, struct chsc_ssqd_area *ssqd)
156 {
157 	memset(ssqd, 0, sizeof(*ssqd));
158 	ssqd->request.length = 0x0010;
159 	ssqd->request.code = 0x0024;
160 	ssqd->first_sch = schid.sch_no;
161 	ssqd->last_sch = schid.sch_no;
162 	ssqd->ssid = schid.ssid;
163 
164 	if (chsc(ssqd))
165 		return -EIO;
166 
167 	return chsc_error_from_response(ssqd->response.code);
168 }
169 EXPORT_SYMBOL_GPL(chsc_ssqd);
170 
171 /**
172  * chsc_sadc() - set adapter device controls (SADC)
173  * @schid: id of the subchannel on which SADC is performed
174  * @scssc: request and response block for SADC
175  * @summary_indicator_addr: summary indicator address
176  * @subchannel_indicator_addr: subchannel indicator address
177  *
178  * Returns 0 on success.
179  */
180 int chsc_sadc(struct subchannel_id schid, struct chsc_scssc_area *scssc,
181 	      u64 summary_indicator_addr, u64 subchannel_indicator_addr)
182 {
183 	memset(scssc, 0, sizeof(*scssc));
184 	scssc->request.length = 0x0fe0;
185 	scssc->request.code = 0x0021;
186 	scssc->operation_code = 0;
187 
188 	scssc->summary_indicator_addr = summary_indicator_addr;
189 	scssc->subchannel_indicator_addr = subchannel_indicator_addr;
190 
191 	scssc->ks = PAGE_DEFAULT_KEY >> 4;
192 	scssc->kc = PAGE_DEFAULT_KEY >> 4;
193 	scssc->isc = QDIO_AIRQ_ISC;
194 	scssc->schid = schid;
195 
196 	/* enable the time delay disablement facility */
197 	if (css_general_characteristics.aif_tdd)
198 		scssc->word_with_d_bit = 0x10000000;
199 
200 	if (chsc(scssc))
201 		return -EIO;
202 
203 	return chsc_error_from_response(scssc->response.code);
204 }
205 EXPORT_SYMBOL_GPL(chsc_sadc);
206 
207 static int s390_subchannel_remove_chpid(struct subchannel *sch, void *data)
208 {
209 	spin_lock_irq(sch->lock);
210 	if (sch->driver && sch->driver->chp_event)
211 		if (sch->driver->chp_event(sch, data, CHP_OFFLINE) != 0)
212 			goto out_unreg;
213 	spin_unlock_irq(sch->lock);
214 	return 0;
215 
216 out_unreg:
217 	sch->lpm = 0;
218 	spin_unlock_irq(sch->lock);
219 	css_schedule_eval(sch->schid);
220 	return 0;
221 }
222 
223 void chsc_chp_offline(struct chp_id chpid)
224 {
225 	char dbf_txt[15];
226 	struct chp_link link;
227 
228 	sprintf(dbf_txt, "chpr%x.%02x", chpid.cssid, chpid.id);
229 	CIO_TRACE_EVENT(2, dbf_txt);
230 
231 	if (chp_get_status(chpid) <= 0)
232 		return;
233 	memset(&link, 0, sizeof(struct chp_link));
234 	link.chpid = chpid;
235 	/* Wait until previous actions have settled. */
236 	css_wait_for_slow_path();
237 	for_each_subchannel_staged(s390_subchannel_remove_chpid, NULL, &link);
238 }
239 
240 static int s390_process_res_acc_new_sch(struct subchannel_id schid, void *data)
241 {
242 	struct schib schib;
243 	/*
244 	 * We don't know the device yet, but since a path
245 	 * may be available now to the device we'll have
246 	 * to do recognition again.
247 	 * Since we don't have any idea about which chpid
248 	 * that beast may be on we'll have to do a stsch
249 	 * on all devices, grr...
250 	 */
251 	if (stsch_err(schid, &schib))
252 		/* We're through */
253 		return -ENXIO;
254 
255 	/* Put it on the slow path. */
256 	css_schedule_eval(schid);
257 	return 0;
258 }
259 
260 static int __s390_process_res_acc(struct subchannel *sch, void *data)
261 {
262 	spin_lock_irq(sch->lock);
263 	if (sch->driver && sch->driver->chp_event)
264 		sch->driver->chp_event(sch, data, CHP_ONLINE);
265 	spin_unlock_irq(sch->lock);
266 
267 	return 0;
268 }
269 
270 static void s390_process_res_acc(struct chp_link *link)
271 {
272 	char dbf_txt[15];
273 
274 	sprintf(dbf_txt, "accpr%x.%02x", link->chpid.cssid,
275 		link->chpid.id);
276 	CIO_TRACE_EVENT( 2, dbf_txt);
277 	if (link->fla != 0) {
278 		sprintf(dbf_txt, "fla%x", link->fla);
279 		CIO_TRACE_EVENT( 2, dbf_txt);
280 	}
281 	/* Wait until previous actions have settled. */
282 	css_wait_for_slow_path();
283 	/*
284 	 * I/O resources may have become accessible.
285 	 * Scan through all subchannels that may be concerned and
286 	 * do a validation on those.
287 	 * The more information we have (info), the less scanning
288 	 * will we have to do.
289 	 */
290 	for_each_subchannel_staged(__s390_process_res_acc,
291 				   s390_process_res_acc_new_sch, link);
292 }
293 
294 static int
295 __get_chpid_from_lir(void *data)
296 {
297 	struct lir {
298 		u8  iq;
299 		u8  ic;
300 		u16 sci;
301 		/* incident-node descriptor */
302 		u32 indesc[28];
303 		/* attached-node descriptor */
304 		u32 andesc[28];
305 		/* incident-specific information */
306 		u32 isinfo[28];
307 	} __attribute__ ((packed)) *lir;
308 
309 	lir = data;
310 	if (!(lir->iq&0x80))
311 		/* NULL link incident record */
312 		return -EINVAL;
313 	if (!(lir->indesc[0]&0xc0000000))
314 		/* node descriptor not valid */
315 		return -EINVAL;
316 	if (!(lir->indesc[0]&0x10000000))
317 		/* don't handle device-type nodes - FIXME */
318 		return -EINVAL;
319 	/* Byte 3 contains the chpid. Could also be CTCA, but we don't care */
320 
321 	return (u16) (lir->indesc[0]&0x000000ff);
322 }
323 
324 struct chsc_sei_nt0_area {
325 	u8  flags;
326 	u8  vf;				/* validity flags */
327 	u8  rs;				/* reporting source */
328 	u8  cc;				/* content code */
329 	u16 fla;			/* full link address */
330 	u16 rsid;			/* reporting source id */
331 	u32 reserved1;
332 	u32 reserved2;
333 	/* ccdf has to be big enough for a link-incident record */
334 	u8  ccdf[PAGE_SIZE - 24 - 16];	/* content-code dependent field */
335 } __packed;
336 
337 struct chsc_sei_nt2_area {
338 	u8  flags;			/* p and v bit */
339 	u8  reserved1;
340 	u8  reserved2;
341 	u8  cc;				/* content code */
342 	u32 reserved3[13];
343 	u8  ccdf[PAGE_SIZE - 24 - 56];	/* content-code dependent field */
344 } __packed;
345 
346 #define CHSC_SEI_NT0	(1ULL << 63)
347 #define CHSC_SEI_NT2	(1ULL << 61)
348 
349 struct chsc_sei {
350 	struct chsc_header request;
351 	u32 reserved1;
352 	u64 ntsm;			/* notification type mask */
353 	struct chsc_header response;
354 	u32 :24;
355 	u8 nt;
356 	union {
357 		struct chsc_sei_nt0_area nt0_area;
358 		struct chsc_sei_nt2_area nt2_area;
359 		u8 nt_area[PAGE_SIZE - 24];
360 	} u;
361 } __packed;
362 
363 static void chsc_process_sei_link_incident(struct chsc_sei_nt0_area *sei_area)
364 {
365 	struct chp_id chpid;
366 	int id;
367 
368 	CIO_CRW_EVENT(4, "chsc: link incident (rs=%02x, rs_id=%04x)\n",
369 		      sei_area->rs, sei_area->rsid);
370 	if (sei_area->rs != 4)
371 		return;
372 	id = __get_chpid_from_lir(sei_area->ccdf);
373 	if (id < 0)
374 		CIO_CRW_EVENT(4, "chsc: link incident - invalid LIR\n");
375 	else {
376 		chp_id_init(&chpid);
377 		chpid.id = id;
378 		chsc_chp_offline(chpid);
379 	}
380 }
381 
382 static void chsc_process_sei_res_acc(struct chsc_sei_nt0_area *sei_area)
383 {
384 	struct chp_link link;
385 	struct chp_id chpid;
386 	int status;
387 
388 	CIO_CRW_EVENT(4, "chsc: resource accessibility event (rs=%02x, "
389 		      "rs_id=%04x)\n", sei_area->rs, sei_area->rsid);
390 	if (sei_area->rs != 4)
391 		return;
392 	chp_id_init(&chpid);
393 	chpid.id = sei_area->rsid;
394 	/* allocate a new channel path structure, if needed */
395 	status = chp_get_status(chpid);
396 	if (status < 0)
397 		chp_new(chpid);
398 	else if (!status)
399 		return;
400 	memset(&link, 0, sizeof(struct chp_link));
401 	link.chpid = chpid;
402 	if ((sei_area->vf & 0xc0) != 0) {
403 		link.fla = sei_area->fla;
404 		if ((sei_area->vf & 0xc0) == 0xc0)
405 			/* full link address */
406 			link.fla_mask = 0xffff;
407 		else
408 			/* link address */
409 			link.fla_mask = 0xff00;
410 	}
411 	s390_process_res_acc(&link);
412 }
413 
414 static void chsc_process_sei_chp_avail(struct chsc_sei_nt0_area *sei_area)
415 {
416 	struct channel_path *chp;
417 	struct chp_id chpid;
418 	u8 *data;
419 	int num;
420 
421 	CIO_CRW_EVENT(4, "chsc: channel path availability information\n");
422 	if (sei_area->rs != 0)
423 		return;
424 	data = sei_area->ccdf;
425 	chp_id_init(&chpid);
426 	for (num = 0; num <= __MAX_CHPID; num++) {
427 		if (!chp_test_bit(data, num))
428 			continue;
429 		chpid.id = num;
430 
431 		CIO_CRW_EVENT(4, "Update information for channel path "
432 			      "%x.%02x\n", chpid.cssid, chpid.id);
433 		chp = chpid_to_chp(chpid);
434 		if (!chp) {
435 			chp_new(chpid);
436 			continue;
437 		}
438 		mutex_lock(&chp->lock);
439 		chp_update_desc(chp);
440 		mutex_unlock(&chp->lock);
441 	}
442 }
443 
444 struct chp_config_data {
445 	u8 map[32];
446 	u8 op;
447 	u8 pc;
448 };
449 
450 static void chsc_process_sei_chp_config(struct chsc_sei_nt0_area *sei_area)
451 {
452 	struct chp_config_data *data;
453 	struct chp_id chpid;
454 	int num;
455 	char *events[3] = {"configure", "deconfigure", "cancel deconfigure"};
456 
457 	CIO_CRW_EVENT(4, "chsc: channel-path-configuration notification\n");
458 	if (sei_area->rs != 0)
459 		return;
460 	data = (struct chp_config_data *) &(sei_area->ccdf);
461 	chp_id_init(&chpid);
462 	for (num = 0; num <= __MAX_CHPID; num++) {
463 		if (!chp_test_bit(data->map, num))
464 			continue;
465 		chpid.id = num;
466 		pr_notice("Processing %s for channel path %x.%02x\n",
467 			  events[data->op], chpid.cssid, chpid.id);
468 		switch (data->op) {
469 		case 0:
470 			chp_cfg_schedule(chpid, 1);
471 			break;
472 		case 1:
473 			chp_cfg_schedule(chpid, 0);
474 			break;
475 		case 2:
476 			chp_cfg_cancel_deconfigure(chpid);
477 			break;
478 		}
479 	}
480 }
481 
482 static void chsc_process_sei_scm_change(struct chsc_sei_nt0_area *sei_area)
483 {
484 	int ret;
485 
486 	CIO_CRW_EVENT(4, "chsc: scm change notification\n");
487 	if (sei_area->rs != 7)
488 		return;
489 
490 	ret = scm_update_information();
491 	if (ret)
492 		CIO_CRW_EVENT(0, "chsc: updating change notification"
493 			      " failed (rc=%d).\n", ret);
494 }
495 
496 static void chsc_process_sei_scm_avail(struct chsc_sei_nt0_area *sei_area)
497 {
498 	int ret;
499 
500 	CIO_CRW_EVENT(4, "chsc: scm available information\n");
501 	if (sei_area->rs != 7)
502 		return;
503 
504 	ret = scm_process_availability_information();
505 	if (ret)
506 		CIO_CRW_EVENT(0, "chsc: process availability information"
507 			      " failed (rc=%d).\n", ret);
508 }
509 
510 static void chsc_process_sei_nt2(struct chsc_sei_nt2_area *sei_area)
511 {
512 	switch (sei_area->cc) {
513 	case 1:
514 		zpci_event_error(sei_area->ccdf);
515 		break;
516 	case 2:
517 		zpci_event_availability(sei_area->ccdf);
518 		break;
519 	default:
520 		CIO_CRW_EVENT(2, "chsc: sei nt2 unhandled cc=%d\n",
521 			      sei_area->cc);
522 		break;
523 	}
524 }
525 
526 static void chsc_process_sei_nt0(struct chsc_sei_nt0_area *sei_area)
527 {
528 	/* which kind of information was stored? */
529 	switch (sei_area->cc) {
530 	case 1: /* link incident*/
531 		chsc_process_sei_link_incident(sei_area);
532 		break;
533 	case 2: /* i/o resource accessibility */
534 		chsc_process_sei_res_acc(sei_area);
535 		break;
536 	case 7: /* channel-path-availability information */
537 		chsc_process_sei_chp_avail(sei_area);
538 		break;
539 	case 8: /* channel-path-configuration notification */
540 		chsc_process_sei_chp_config(sei_area);
541 		break;
542 	case 12: /* scm change notification */
543 		chsc_process_sei_scm_change(sei_area);
544 		break;
545 	case 14: /* scm available notification */
546 		chsc_process_sei_scm_avail(sei_area);
547 		break;
548 	default: /* other stuff */
549 		CIO_CRW_EVENT(2, "chsc: sei nt0 unhandled cc=%d\n",
550 			      sei_area->cc);
551 		break;
552 	}
553 
554 	/* Check if we might have lost some information. */
555 	if (sei_area->flags & 0x40) {
556 		CIO_CRW_EVENT(2, "chsc: event overflow\n");
557 		css_schedule_eval_all();
558 	}
559 }
560 
561 static void chsc_process_event_information(struct chsc_sei *sei, u64 ntsm)
562 {
563 	do {
564 		memset(sei, 0, sizeof(*sei));
565 		sei->request.length = 0x0010;
566 		sei->request.code = 0x000e;
567 		sei->ntsm = ntsm;
568 
569 		if (chsc(sei))
570 			break;
571 
572 		if (sei->response.code != 0x0001) {
573 			CIO_CRW_EVENT(2, "chsc: sei failed (rc=%04x)\n",
574 				      sei->response.code);
575 			break;
576 		}
577 
578 		CIO_CRW_EVENT(2, "chsc: sei successful (nt=%d)\n", sei->nt);
579 		switch (sei->nt) {
580 		case 0:
581 			chsc_process_sei_nt0(&sei->u.nt0_area);
582 			break;
583 		case 2:
584 			chsc_process_sei_nt2(&sei->u.nt2_area);
585 			break;
586 		default:
587 			CIO_CRW_EVENT(2, "chsc: unhandled nt: %d\n", sei->nt);
588 			break;
589 		}
590 	} while (sei->u.nt0_area.flags & 0x80);
591 }
592 
593 /*
594  * Handle channel subsystem related CRWs.
595  * Use store event information to find out what's going on.
596  *
597  * Note: Access to sei_page is serialized through machine check handler
598  * thread, so no need for locking.
599  */
600 static void chsc_process_crw(struct crw *crw0, struct crw *crw1, int overflow)
601 {
602 	struct chsc_sei *sei = sei_page;
603 
604 	if (overflow) {
605 		css_schedule_eval_all();
606 		return;
607 	}
608 	CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, "
609 		      "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
610 		      crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
611 		      crw0->erc, crw0->rsid);
612 
613 	CIO_TRACE_EVENT(2, "prcss");
614 	chsc_process_event_information(sei, CHSC_SEI_NT0 | CHSC_SEI_NT2);
615 }
616 
617 void chsc_chp_online(struct chp_id chpid)
618 {
619 	char dbf_txt[15];
620 	struct chp_link link;
621 
622 	sprintf(dbf_txt, "cadd%x.%02x", chpid.cssid, chpid.id);
623 	CIO_TRACE_EVENT(2, dbf_txt);
624 
625 	if (chp_get_status(chpid) != 0) {
626 		memset(&link, 0, sizeof(struct chp_link));
627 		link.chpid = chpid;
628 		/* Wait until previous actions have settled. */
629 		css_wait_for_slow_path();
630 		for_each_subchannel_staged(__s390_process_res_acc, NULL,
631 					   &link);
632 	}
633 }
634 
635 static void __s390_subchannel_vary_chpid(struct subchannel *sch,
636 					 struct chp_id chpid, int on)
637 {
638 	unsigned long flags;
639 	struct chp_link link;
640 
641 	memset(&link, 0, sizeof(struct chp_link));
642 	link.chpid = chpid;
643 	spin_lock_irqsave(sch->lock, flags);
644 	if (sch->driver && sch->driver->chp_event)
645 		sch->driver->chp_event(sch, &link,
646 				       on ? CHP_VARY_ON : CHP_VARY_OFF);
647 	spin_unlock_irqrestore(sch->lock, flags);
648 }
649 
650 static int s390_subchannel_vary_chpid_off(struct subchannel *sch, void *data)
651 {
652 	struct chp_id *chpid = data;
653 
654 	__s390_subchannel_vary_chpid(sch, *chpid, 0);
655 	return 0;
656 }
657 
658 static int s390_subchannel_vary_chpid_on(struct subchannel *sch, void *data)
659 {
660 	struct chp_id *chpid = data;
661 
662 	__s390_subchannel_vary_chpid(sch, *chpid, 1);
663 	return 0;
664 }
665 
666 static int
667 __s390_vary_chpid_on(struct subchannel_id schid, void *data)
668 {
669 	struct schib schib;
670 
671 	if (stsch_err(schid, &schib))
672 		/* We're through */
673 		return -ENXIO;
674 	/* Put it on the slow path. */
675 	css_schedule_eval(schid);
676 	return 0;
677 }
678 
679 /**
680  * chsc_chp_vary - propagate channel-path vary operation to subchannels
681  * @chpid: channl-path ID
682  * @on: non-zero for vary online, zero for vary offline
683  */
684 int chsc_chp_vary(struct chp_id chpid, int on)
685 {
686 	struct channel_path *chp = chpid_to_chp(chpid);
687 
688 	/* Wait until previous actions have settled. */
689 	css_wait_for_slow_path();
690 	/*
691 	 * Redo PathVerification on the devices the chpid connects to
692 	 */
693 	if (on) {
694 		/* Try to update the channel path description. */
695 		chp_update_desc(chp);
696 		for_each_subchannel_staged(s390_subchannel_vary_chpid_on,
697 					   __s390_vary_chpid_on, &chpid);
698 	} else
699 		for_each_subchannel_staged(s390_subchannel_vary_chpid_off,
700 					   NULL, &chpid);
701 
702 	return 0;
703 }
704 
705 static void
706 chsc_remove_cmg_attr(struct channel_subsystem *css)
707 {
708 	int i;
709 
710 	for (i = 0; i <= __MAX_CHPID; i++) {
711 		if (!css->chps[i])
712 			continue;
713 		chp_remove_cmg_attr(css->chps[i]);
714 	}
715 }
716 
717 static int
718 chsc_add_cmg_attr(struct channel_subsystem *css)
719 {
720 	int i, ret;
721 
722 	ret = 0;
723 	for (i = 0; i <= __MAX_CHPID; i++) {
724 		if (!css->chps[i])
725 			continue;
726 		ret = chp_add_cmg_attr(css->chps[i]);
727 		if (ret)
728 			goto cleanup;
729 	}
730 	return ret;
731 cleanup:
732 	for (--i; i >= 0; i--) {
733 		if (!css->chps[i])
734 			continue;
735 		chp_remove_cmg_attr(css->chps[i]);
736 	}
737 	return ret;
738 }
739 
740 int __chsc_do_secm(struct channel_subsystem *css, int enable)
741 {
742 	struct {
743 		struct chsc_header request;
744 		u32 operation_code : 2;
745 		u32 : 30;
746 		u32 key : 4;
747 		u32 : 28;
748 		u32 zeroes1;
749 		u32 cub_addr1;
750 		u32 zeroes2;
751 		u32 cub_addr2;
752 		u32 reserved[13];
753 		struct chsc_header response;
754 		u32 status : 8;
755 		u32 : 4;
756 		u32 fmt : 4;
757 		u32 : 16;
758 	} __attribute__ ((packed)) *secm_area;
759 	int ret, ccode;
760 
761 	spin_lock_irq(&chsc_page_lock);
762 	memset(chsc_page, 0, PAGE_SIZE);
763 	secm_area = chsc_page;
764 	secm_area->request.length = 0x0050;
765 	secm_area->request.code = 0x0016;
766 
767 	secm_area->key = PAGE_DEFAULT_KEY >> 4;
768 	secm_area->cub_addr1 = (u64)(unsigned long)css->cub_addr1;
769 	secm_area->cub_addr2 = (u64)(unsigned long)css->cub_addr2;
770 
771 	secm_area->operation_code = enable ? 0 : 1;
772 
773 	ccode = chsc(secm_area);
774 	if (ccode > 0) {
775 		ret = (ccode == 3) ? -ENODEV : -EBUSY;
776 		goto out;
777 	}
778 
779 	switch (secm_area->response.code) {
780 	case 0x0102:
781 	case 0x0103:
782 		ret = -EINVAL;
783 		break;
784 	default:
785 		ret = chsc_error_from_response(secm_area->response.code);
786 	}
787 	if (ret != 0)
788 		CIO_CRW_EVENT(2, "chsc: secm failed (rc=%04x)\n",
789 			      secm_area->response.code);
790 out:
791 	spin_unlock_irq(&chsc_page_lock);
792 	return ret;
793 }
794 
795 int
796 chsc_secm(struct channel_subsystem *css, int enable)
797 {
798 	int ret;
799 
800 	if (enable && !css->cm_enabled) {
801 		css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
802 		css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
803 		if (!css->cub_addr1 || !css->cub_addr2) {
804 			free_page((unsigned long)css->cub_addr1);
805 			free_page((unsigned long)css->cub_addr2);
806 			return -ENOMEM;
807 		}
808 	}
809 	ret = __chsc_do_secm(css, enable);
810 	if (!ret) {
811 		css->cm_enabled = enable;
812 		if (css->cm_enabled) {
813 			ret = chsc_add_cmg_attr(css);
814 			if (ret) {
815 				__chsc_do_secm(css, 0);
816 				css->cm_enabled = 0;
817 			}
818 		} else
819 			chsc_remove_cmg_attr(css);
820 	}
821 	if (!css->cm_enabled) {
822 		free_page((unsigned long)css->cub_addr1);
823 		free_page((unsigned long)css->cub_addr2);
824 	}
825 	return ret;
826 }
827 
828 int chsc_determine_channel_path_desc(struct chp_id chpid, int fmt, int rfmt,
829 				     int c, int m, void *page)
830 {
831 	struct chsc_scpd *scpd_area;
832 	int ccode, ret;
833 
834 	if ((rfmt == 1) && !css_general_characteristics.fcs)
835 		return -EINVAL;
836 	if ((rfmt == 2) && !css_general_characteristics.cib)
837 		return -EINVAL;
838 
839 	memset(page, 0, PAGE_SIZE);
840 	scpd_area = page;
841 	scpd_area->request.length = 0x0010;
842 	scpd_area->request.code = 0x0002;
843 	scpd_area->cssid = chpid.cssid;
844 	scpd_area->first_chpid = chpid.id;
845 	scpd_area->last_chpid = chpid.id;
846 	scpd_area->m = m;
847 	scpd_area->c = c;
848 	scpd_area->fmt = fmt;
849 	scpd_area->rfmt = rfmt;
850 
851 	ccode = chsc(scpd_area);
852 	if (ccode > 0)
853 		return (ccode == 3) ? -ENODEV : -EBUSY;
854 
855 	ret = chsc_error_from_response(scpd_area->response.code);
856 	if (ret)
857 		CIO_CRW_EVENT(2, "chsc: scpd failed (rc=%04x)\n",
858 			      scpd_area->response.code);
859 	return ret;
860 }
861 EXPORT_SYMBOL_GPL(chsc_determine_channel_path_desc);
862 
863 int chsc_determine_base_channel_path_desc(struct chp_id chpid,
864 					  struct channel_path_desc *desc)
865 {
866 	struct chsc_response_struct *chsc_resp;
867 	struct chsc_scpd *scpd_area;
868 	unsigned long flags;
869 	int ret;
870 
871 	spin_lock_irqsave(&chsc_page_lock, flags);
872 	scpd_area = chsc_page;
873 	ret = chsc_determine_channel_path_desc(chpid, 0, 0, 0, 0, scpd_area);
874 	if (ret)
875 		goto out;
876 	chsc_resp = (void *)&scpd_area->response;
877 	memcpy(desc, &chsc_resp->data, sizeof(*desc));
878 out:
879 	spin_unlock_irqrestore(&chsc_page_lock, flags);
880 	return ret;
881 }
882 
883 int chsc_determine_fmt1_channel_path_desc(struct chp_id chpid,
884 					  struct channel_path_desc_fmt1 *desc)
885 {
886 	struct chsc_response_struct *chsc_resp;
887 	struct chsc_scpd *scpd_area;
888 	unsigned long flags;
889 	int ret;
890 
891 	spin_lock_irqsave(&chsc_page_lock, flags);
892 	scpd_area = chsc_page;
893 	ret = chsc_determine_channel_path_desc(chpid, 0, 0, 1, 0, scpd_area);
894 	if (ret)
895 		goto out;
896 	chsc_resp = (void *)&scpd_area->response;
897 	memcpy(desc, &chsc_resp->data, sizeof(*desc));
898 out:
899 	spin_unlock_irqrestore(&chsc_page_lock, flags);
900 	return ret;
901 }
902 
903 static void
904 chsc_initialize_cmg_chars(struct channel_path *chp, u8 cmcv,
905 			  struct cmg_chars *chars)
906 {
907 	struct cmg_chars *cmg_chars;
908 	int i, mask;
909 
910 	cmg_chars = chp->cmg_chars;
911 	for (i = 0; i < NR_MEASUREMENT_CHARS; i++) {
912 		mask = 0x80 >> (i + 3);
913 		if (cmcv & mask)
914 			cmg_chars->values[i] = chars->values[i];
915 		else
916 			cmg_chars->values[i] = 0;
917 	}
918 }
919 
920 int chsc_get_channel_measurement_chars(struct channel_path *chp)
921 {
922 	struct cmg_chars *cmg_chars;
923 	int ccode, ret;
924 
925 	struct {
926 		struct chsc_header request;
927 		u32 : 24;
928 		u32 first_chpid : 8;
929 		u32 : 24;
930 		u32 last_chpid : 8;
931 		u32 zeroes1;
932 		struct chsc_header response;
933 		u32 zeroes2;
934 		u32 not_valid : 1;
935 		u32 shared : 1;
936 		u32 : 22;
937 		u32 chpid : 8;
938 		u32 cmcv : 5;
939 		u32 : 11;
940 		u32 cmgq : 8;
941 		u32 cmg : 8;
942 		u32 zeroes3;
943 		u32 data[NR_MEASUREMENT_CHARS];
944 	} __attribute__ ((packed)) *scmc_area;
945 
946 	chp->cmg_chars = NULL;
947 	cmg_chars = kmalloc(sizeof(*cmg_chars), GFP_KERNEL);
948 	if (!cmg_chars)
949 		return -ENOMEM;
950 
951 	spin_lock_irq(&chsc_page_lock);
952 	memset(chsc_page, 0, PAGE_SIZE);
953 	scmc_area = chsc_page;
954 	scmc_area->request.length = 0x0010;
955 	scmc_area->request.code = 0x0022;
956 	scmc_area->first_chpid = chp->chpid.id;
957 	scmc_area->last_chpid = chp->chpid.id;
958 
959 	ccode = chsc(scmc_area);
960 	if (ccode > 0) {
961 		ret = (ccode == 3) ? -ENODEV : -EBUSY;
962 		goto out;
963 	}
964 
965 	ret = chsc_error_from_response(scmc_area->response.code);
966 	if (ret) {
967 		CIO_CRW_EVENT(2, "chsc: scmc failed (rc=%04x)\n",
968 			      scmc_area->response.code);
969 		goto out;
970 	}
971 	if (scmc_area->not_valid) {
972 		chp->cmg = -1;
973 		chp->shared = -1;
974 		goto out;
975 	}
976 	chp->cmg = scmc_area->cmg;
977 	chp->shared = scmc_area->shared;
978 	if (chp->cmg != 2 && chp->cmg != 3) {
979 		/* No cmg-dependent data. */
980 		goto out;
981 	}
982 	chp->cmg_chars = cmg_chars;
983 	chsc_initialize_cmg_chars(chp, scmc_area->cmcv,
984 				  (struct cmg_chars *) &scmc_area->data);
985 out:
986 	spin_unlock_irq(&chsc_page_lock);
987 	if (!chp->cmg_chars)
988 		kfree(cmg_chars);
989 
990 	return ret;
991 }
992 
993 int __init chsc_init(void)
994 {
995 	int ret;
996 
997 	sei_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
998 	chsc_page = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
999 	if (!sei_page || !chsc_page) {
1000 		ret = -ENOMEM;
1001 		goto out_err;
1002 	}
1003 	ret = crw_register_handler(CRW_RSC_CSS, chsc_process_crw);
1004 	if (ret)
1005 		goto out_err;
1006 	return ret;
1007 out_err:
1008 	free_page((unsigned long)chsc_page);
1009 	free_page((unsigned long)sei_page);
1010 	return ret;
1011 }
1012 
1013 void __init chsc_init_cleanup(void)
1014 {
1015 	crw_unregister_handler(CRW_RSC_CSS);
1016 	free_page((unsigned long)chsc_page);
1017 	free_page((unsigned long)sei_page);
1018 }
1019 
1020 int chsc_enable_facility(int operation_code)
1021 {
1022 	unsigned long flags;
1023 	int ret;
1024 	struct {
1025 		struct chsc_header request;
1026 		u8 reserved1:4;
1027 		u8 format:4;
1028 		u8 reserved2;
1029 		u16 operation_code;
1030 		u32 reserved3;
1031 		u32 reserved4;
1032 		u32 operation_data_area[252];
1033 		struct chsc_header response;
1034 		u32 reserved5:4;
1035 		u32 format2:4;
1036 		u32 reserved6:24;
1037 	} __attribute__ ((packed)) *sda_area;
1038 
1039 	spin_lock_irqsave(&chsc_page_lock, flags);
1040 	memset(chsc_page, 0, PAGE_SIZE);
1041 	sda_area = chsc_page;
1042 	sda_area->request.length = 0x0400;
1043 	sda_area->request.code = 0x0031;
1044 	sda_area->operation_code = operation_code;
1045 
1046 	ret = chsc(sda_area);
1047 	if (ret > 0) {
1048 		ret = (ret == 3) ? -ENODEV : -EBUSY;
1049 		goto out;
1050 	}
1051 
1052 	switch (sda_area->response.code) {
1053 	case 0x0101:
1054 		ret = -EOPNOTSUPP;
1055 		break;
1056 	default:
1057 		ret = chsc_error_from_response(sda_area->response.code);
1058 	}
1059 	if (ret != 0)
1060 		CIO_CRW_EVENT(2, "chsc: sda (oc=%x) failed (rc=%04x)\n",
1061 			      operation_code, sda_area->response.code);
1062 out:
1063 	spin_unlock_irqrestore(&chsc_page_lock, flags);
1064 	return ret;
1065 }
1066 
1067 struct css_general_char css_general_characteristics;
1068 struct css_chsc_char css_chsc_characteristics;
1069 
1070 int __init
1071 chsc_determine_css_characteristics(void)
1072 {
1073 	int result;
1074 	struct {
1075 		struct chsc_header request;
1076 		u32 reserved1;
1077 		u32 reserved2;
1078 		u32 reserved3;
1079 		struct chsc_header response;
1080 		u32 reserved4;
1081 		u32 general_char[510];
1082 		u32 chsc_char[508];
1083 	} __attribute__ ((packed)) *scsc_area;
1084 
1085 	spin_lock_irq(&chsc_page_lock);
1086 	memset(chsc_page, 0, PAGE_SIZE);
1087 	scsc_area = chsc_page;
1088 	scsc_area->request.length = 0x0010;
1089 	scsc_area->request.code = 0x0010;
1090 
1091 	result = chsc(scsc_area);
1092 	if (result) {
1093 		result = (result == 3) ? -ENODEV : -EBUSY;
1094 		goto exit;
1095 	}
1096 
1097 	result = chsc_error_from_response(scsc_area->response.code);
1098 	if (result == 0) {
1099 		memcpy(&css_general_characteristics, scsc_area->general_char,
1100 		       sizeof(css_general_characteristics));
1101 		memcpy(&css_chsc_characteristics, scsc_area->chsc_char,
1102 		       sizeof(css_chsc_characteristics));
1103 	} else
1104 		CIO_CRW_EVENT(2, "chsc: scsc failed (rc=%04x)\n",
1105 			      scsc_area->response.code);
1106 exit:
1107 	spin_unlock_irq(&chsc_page_lock);
1108 	return result;
1109 }
1110 
1111 EXPORT_SYMBOL_GPL(css_general_characteristics);
1112 EXPORT_SYMBOL_GPL(css_chsc_characteristics);
1113 
1114 int chsc_sstpc(void *page, unsigned int op, u16 ctrl)
1115 {
1116 	struct {
1117 		struct chsc_header request;
1118 		unsigned int rsvd0;
1119 		unsigned int op : 8;
1120 		unsigned int rsvd1 : 8;
1121 		unsigned int ctrl : 16;
1122 		unsigned int rsvd2[5];
1123 		struct chsc_header response;
1124 		unsigned int rsvd3[7];
1125 	} __attribute__ ((packed)) *rr;
1126 	int rc;
1127 
1128 	memset(page, 0, PAGE_SIZE);
1129 	rr = page;
1130 	rr->request.length = 0x0020;
1131 	rr->request.code = 0x0033;
1132 	rr->op = op;
1133 	rr->ctrl = ctrl;
1134 	rc = chsc(rr);
1135 	if (rc)
1136 		return -EIO;
1137 	rc = (rr->response.code == 0x0001) ? 0 : -EIO;
1138 	return rc;
1139 }
1140 
1141 int chsc_sstpi(void *page, void *result, size_t size)
1142 {
1143 	struct {
1144 		struct chsc_header request;
1145 		unsigned int rsvd0[3];
1146 		struct chsc_header response;
1147 		char data[size];
1148 	} __attribute__ ((packed)) *rr;
1149 	int rc;
1150 
1151 	memset(page, 0, PAGE_SIZE);
1152 	rr = page;
1153 	rr->request.length = 0x0010;
1154 	rr->request.code = 0x0038;
1155 	rc = chsc(rr);
1156 	if (rc)
1157 		return -EIO;
1158 	memcpy(result, &rr->data, size);
1159 	return (rr->response.code == 0x0001) ? 0 : -EIO;
1160 }
1161 
1162 int chsc_siosl(struct subchannel_id schid)
1163 {
1164 	struct {
1165 		struct chsc_header request;
1166 		u32 word1;
1167 		struct subchannel_id sid;
1168 		u32 word3;
1169 		struct chsc_header response;
1170 		u32 word[11];
1171 	} __attribute__ ((packed)) *siosl_area;
1172 	unsigned long flags;
1173 	int ccode;
1174 	int rc;
1175 
1176 	spin_lock_irqsave(&chsc_page_lock, flags);
1177 	memset(chsc_page, 0, PAGE_SIZE);
1178 	siosl_area = chsc_page;
1179 	siosl_area->request.length = 0x0010;
1180 	siosl_area->request.code = 0x0046;
1181 	siosl_area->word1 = 0x80000000;
1182 	siosl_area->sid = schid;
1183 
1184 	ccode = chsc(siosl_area);
1185 	if (ccode > 0) {
1186 		if (ccode == 3)
1187 			rc = -ENODEV;
1188 		else
1189 			rc = -EBUSY;
1190 		CIO_MSG_EVENT(2, "chsc: chsc failed for 0.%x.%04x (ccode=%d)\n",
1191 			      schid.ssid, schid.sch_no, ccode);
1192 		goto out;
1193 	}
1194 	rc = chsc_error_from_response(siosl_area->response.code);
1195 	if (rc)
1196 		CIO_MSG_EVENT(2, "chsc: siosl failed for 0.%x.%04x (rc=%04x)\n",
1197 			      schid.ssid, schid.sch_no,
1198 			      siosl_area->response.code);
1199 	else
1200 		CIO_MSG_EVENT(4, "chsc: siosl succeeded for 0.%x.%04x\n",
1201 			      schid.ssid, schid.sch_no);
1202 out:
1203 	spin_unlock_irqrestore(&chsc_page_lock, flags);
1204 	return rc;
1205 }
1206 EXPORT_SYMBOL_GPL(chsc_siosl);
1207 
1208 /**
1209  * chsc_scm_info() - store SCM information (SSI)
1210  * @scm_area: request and response block for SSI
1211  * @token: continuation token
1212  *
1213  * Returns 0 on success.
1214  */
1215 int chsc_scm_info(struct chsc_scm_info *scm_area, u64 token)
1216 {
1217 	int ccode, ret;
1218 
1219 	memset(scm_area, 0, sizeof(*scm_area));
1220 	scm_area->request.length = 0x0020;
1221 	scm_area->request.code = 0x004C;
1222 	scm_area->reqtok = token;
1223 
1224 	ccode = chsc(scm_area);
1225 	if (ccode > 0) {
1226 		ret = (ccode == 3) ? -ENODEV : -EBUSY;
1227 		goto out;
1228 	}
1229 	ret = chsc_error_from_response(scm_area->response.code);
1230 	if (ret != 0)
1231 		CIO_MSG_EVENT(2, "chsc: scm info failed (rc=%04x)\n",
1232 			      scm_area->response.code);
1233 out:
1234 	return ret;
1235 }
1236 EXPORT_SYMBOL_GPL(chsc_scm_info);
1237