1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * S/390 common I/O routines -- low level i/o calls
4 *
5 * Copyright IBM Corp. 1999, 2008
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 * Martin Schwidefsky (schwidefsky@de.ibm.com)
10 */
11
12 #define KMSG_COMPONENT "cio"
13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
14
15 #include <linux/ftrace.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/slab.h>
19 #include <linux/device.h>
20 #include <linux/kernel_stat.h>
21 #include <linux/interrupt.h>
22 #include <linux/irq.h>
23 #include <asm/cio.h>
24 #include <asm/delay.h>
25 #include <asm/irq.h>
26 #include <asm/irq_regs.h>
27 #include <asm/setup.h>
28 #include <asm/ipl.h>
29 #include <asm/chpid.h>
30 #include <asm/airq.h>
31 #include <asm/isc.h>
32 #include <linux/sched/cputime.h>
33 #include <asm/fcx.h>
34 #include <asm/nmi.h>
35 #include <asm/crw.h>
36 #include "cio.h"
37 #include "css.h"
38 #include "chsc.h"
39 #include "ioasm.h"
40 #include "io_sch.h"
41 #include "blacklist.h"
42 #include "cio_debug.h"
43 #include "chp.h"
44 #include "trace.h"
45
46 debug_info_t *cio_debug_msg_id;
47 debug_info_t *cio_debug_trace_id;
48 debug_info_t *cio_debug_crw_id;
49
50 DEFINE_PER_CPU_ALIGNED(struct irb, cio_irb);
51 EXPORT_PER_CPU_SYMBOL(cio_irb);
52
53 /*
54 * Function: cio_debug_init
55 * Initializes three debug logs for common I/O:
56 * - cio_msg logs generic cio messages
57 * - cio_trace logs the calling of different functions
58 * - cio_crw logs machine check related cio messages
59 */
cio_debug_init(void)60 static int __init cio_debug_init(void)
61 {
62 cio_debug_msg_id = debug_register("cio_msg", 16, 1, 11 * sizeof(long));
63 if (!cio_debug_msg_id)
64 goto out_unregister;
65 debug_register_view(cio_debug_msg_id, &debug_sprintf_view);
66 debug_set_level(cio_debug_msg_id, 2);
67 cio_debug_trace_id = debug_register("cio_trace", 16, 1, 16);
68 if (!cio_debug_trace_id)
69 goto out_unregister;
70 debug_register_view(cio_debug_trace_id, &debug_hex_ascii_view);
71 debug_set_level(cio_debug_trace_id, 2);
72 cio_debug_crw_id = debug_register("cio_crw", 8, 1, 8 * sizeof(long));
73 if (!cio_debug_crw_id)
74 goto out_unregister;
75 debug_register_view(cio_debug_crw_id, &debug_sprintf_view);
76 debug_set_level(cio_debug_crw_id, 4);
77 return 0;
78
79 out_unregister:
80 debug_unregister(cio_debug_msg_id);
81 debug_unregister(cio_debug_trace_id);
82 debug_unregister(cio_debug_crw_id);
83 return -1;
84 }
85
86 arch_initcall (cio_debug_init);
87
cio_set_options(struct subchannel * sch,int flags)88 int cio_set_options(struct subchannel *sch, int flags)
89 {
90 struct io_subchannel_private *priv = to_io_private(sch);
91
92 priv->options.suspend = (flags & DOIO_ALLOW_SUSPEND) != 0;
93 priv->options.prefetch = (flags & DOIO_DENY_PREFETCH) != 0;
94 priv->options.inter = (flags & DOIO_SUPPRESS_INTER) != 0;
95 return 0;
96 }
97
98 static int
cio_start_handle_notoper(struct subchannel * sch,__u8 lpm)99 cio_start_handle_notoper(struct subchannel *sch, __u8 lpm)
100 {
101 char dbf_text[15];
102
103 if (lpm != 0)
104 sch->lpm &= ~lpm;
105 else
106 sch->lpm = 0;
107
108 CIO_MSG_EVENT(2, "cio_start: 'not oper' status for "
109 "subchannel 0.%x.%04x!\n", sch->schid.ssid,
110 sch->schid.sch_no);
111
112 if (cio_update_schib(sch))
113 return -ENODEV;
114
115 sprintf(dbf_text, "no%s", dev_name(&sch->dev));
116 CIO_TRACE_EVENT(0, dbf_text);
117 CIO_HEX_EVENT(0, &sch->schib, sizeof (struct schib));
118
119 return (sch->lpm ? -EACCES : -ENODEV);
120 }
121
122 int
cio_start_key(struct subchannel * sch,struct ccw1 * cpa,__u8 lpm,__u8 key)123 cio_start_key (struct subchannel *sch, /* subchannel structure */
124 struct ccw1 * cpa, /* logical channel prog addr */
125 __u8 lpm, /* logical path mask */
126 __u8 key) /* storage key */
127 {
128 struct io_subchannel_private *priv = to_io_private(sch);
129 union orb *orb = &priv->orb;
130 int ccode;
131
132 CIO_TRACE_EVENT(5, "stIO");
133 CIO_TRACE_EVENT(5, dev_name(&sch->dev));
134
135 memset(orb, 0, sizeof(union orb));
136 /* sch is always under 2G. */
137 orb->cmd.intparm = (u32)(addr_t)sch;
138 orb->cmd.fmt = 1;
139
140 orb->cmd.pfch = priv->options.prefetch == 0;
141 orb->cmd.spnd = priv->options.suspend;
142 orb->cmd.ssic = priv->options.suspend && priv->options.inter;
143 orb->cmd.lpm = (lpm != 0) ? lpm : sch->lpm;
144 /*
145 * for 64 bit we always support 64 bit IDAWs with 4k page size only
146 */
147 orb->cmd.c64 = 1;
148 orb->cmd.i2k = 0;
149 orb->cmd.key = key >> 4;
150 /* issue "Start Subchannel" */
151 orb->cmd.cpa = (__u32) __pa(cpa);
152 ccode = ssch(sch->schid, orb);
153
154 /* process condition code */
155 CIO_HEX_EVENT(5, &ccode, sizeof(ccode));
156
157 switch (ccode) {
158 case 0:
159 /*
160 * initialize device status information
161 */
162 sch->schib.scsw.cmd.actl |= SCSW_ACTL_START_PEND;
163 return 0;
164 case 1: /* status pending */
165 case 2: /* busy */
166 return -EBUSY;
167 case 3: /* device/path not operational */
168 return cio_start_handle_notoper(sch, lpm);
169 default:
170 return ccode;
171 }
172 }
173 EXPORT_SYMBOL_GPL(cio_start_key);
174
175 int
cio_start(struct subchannel * sch,struct ccw1 * cpa,__u8 lpm)176 cio_start (struct subchannel *sch, struct ccw1 *cpa, __u8 lpm)
177 {
178 return cio_start_key(sch, cpa, lpm, PAGE_DEFAULT_KEY);
179 }
180 EXPORT_SYMBOL_GPL(cio_start);
181
182 /*
183 * resume suspended I/O operation
184 */
185 int
cio_resume(struct subchannel * sch)186 cio_resume (struct subchannel *sch)
187 {
188 int ccode;
189
190 CIO_TRACE_EVENT(4, "resIO");
191 CIO_TRACE_EVENT(4, dev_name(&sch->dev));
192
193 ccode = rsch (sch->schid);
194
195 CIO_HEX_EVENT(4, &ccode, sizeof(ccode));
196
197 switch (ccode) {
198 case 0:
199 sch->schib.scsw.cmd.actl |= SCSW_ACTL_RESUME_PEND;
200 return 0;
201 case 1:
202 return -EBUSY;
203 case 2:
204 return -EINVAL;
205 default:
206 /*
207 * useless to wait for request completion
208 * as device is no longer operational !
209 */
210 return -ENODEV;
211 }
212 }
213 EXPORT_SYMBOL_GPL(cio_resume);
214
215 /*
216 * halt I/O operation
217 */
218 int
cio_halt(struct subchannel * sch)219 cio_halt(struct subchannel *sch)
220 {
221 int ccode;
222
223 if (!sch)
224 return -ENODEV;
225
226 CIO_TRACE_EVENT(2, "haltIO");
227 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
228
229 /*
230 * Issue "Halt subchannel" and process condition code
231 */
232 ccode = hsch (sch->schid);
233
234 CIO_HEX_EVENT(2, &ccode, sizeof(ccode));
235
236 switch (ccode) {
237 case 0:
238 sch->schib.scsw.cmd.actl |= SCSW_ACTL_HALT_PEND;
239 return 0;
240 case 1: /* status pending */
241 case 2: /* busy */
242 return -EBUSY;
243 default: /* device not operational */
244 return -ENODEV;
245 }
246 }
247 EXPORT_SYMBOL_GPL(cio_halt);
248
249 /*
250 * Clear I/O operation
251 */
252 int
cio_clear(struct subchannel * sch)253 cio_clear(struct subchannel *sch)
254 {
255 int ccode;
256
257 if (!sch)
258 return -ENODEV;
259
260 CIO_TRACE_EVENT(2, "clearIO");
261 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
262
263 /*
264 * Issue "Clear subchannel" and process condition code
265 */
266 ccode = csch (sch->schid);
267
268 CIO_HEX_EVENT(2, &ccode, sizeof(ccode));
269
270 switch (ccode) {
271 case 0:
272 sch->schib.scsw.cmd.actl |= SCSW_ACTL_CLEAR_PEND;
273 return 0;
274 default: /* device not operational */
275 return -ENODEV;
276 }
277 }
278 EXPORT_SYMBOL_GPL(cio_clear);
279
280 /*
281 * Function: cio_cancel
282 * Issues a "Cancel Subchannel" on the specified subchannel
283 * Note: We don't need any fancy intparms and flags here
284 * since xsch is executed synchronously.
285 * Only for common I/O internal use as for now.
286 */
287 int
cio_cancel(struct subchannel * sch)288 cio_cancel (struct subchannel *sch)
289 {
290 int ccode;
291
292 if (!sch)
293 return -ENODEV;
294
295 CIO_TRACE_EVENT(2, "cancelIO");
296 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
297
298 ccode = xsch (sch->schid);
299
300 CIO_HEX_EVENT(2, &ccode, sizeof(ccode));
301
302 switch (ccode) {
303 case 0: /* success */
304 /* Update information in scsw. */
305 if (cio_update_schib(sch))
306 return -ENODEV;
307 return 0;
308 case 1: /* status pending */
309 return -EBUSY;
310 case 2: /* not applicable */
311 return -EINVAL;
312 default: /* not oper */
313 return -ENODEV;
314 }
315 }
316 EXPORT_SYMBOL_GPL(cio_cancel);
317
318 /**
319 * cio_cancel_halt_clear - Cancel running I/O by performing cancel, halt
320 * and clear ordinally if subchannel is valid.
321 * @sch: subchannel on which to perform the cancel_halt_clear operation
322 * @iretry: the number of the times remained to retry the next operation
323 *
324 * This should be called repeatedly since halt/clear are asynchronous
325 * operations. We do one try with cio_cancel, three tries with cio_halt,
326 * 255 tries with cio_clear. The caller should initialize @iretry with
327 * the value 255 for its first call to this, and keep using the same
328 * @iretry in the subsequent calls until it gets a non -EBUSY return.
329 *
330 * Returns 0 if device now idle, -ENODEV for device not operational,
331 * -EBUSY if an interrupt is expected (either from halt/clear or from a
332 * status pending), and -EIO if out of retries.
333 */
cio_cancel_halt_clear(struct subchannel * sch,int * iretry)334 int cio_cancel_halt_clear(struct subchannel *sch, int *iretry)
335 {
336 int ret;
337
338 if (cio_update_schib(sch))
339 return -ENODEV;
340 if (!sch->schib.pmcw.ena)
341 /* Not operational -> done. */
342 return 0;
343 /* Stage 1: cancel io. */
344 if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_HALT_PEND) &&
345 !(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
346 if (!scsw_is_tm(&sch->schib.scsw)) {
347 ret = cio_cancel(sch);
348 if (ret != -EINVAL)
349 return ret;
350 }
351 /*
352 * Cancel io unsuccessful or not applicable (transport mode).
353 * Continue with asynchronous instructions.
354 */
355 *iretry = 3; /* 3 halt retries. */
356 }
357 /* Stage 2: halt io. */
358 if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
359 if (*iretry) {
360 *iretry -= 1;
361 ret = cio_halt(sch);
362 if (ret != -EBUSY)
363 return (ret == 0) ? -EBUSY : ret;
364 }
365 /* Halt io unsuccessful. */
366 *iretry = 255; /* 255 clear retries. */
367 }
368 /* Stage 3: clear io. */
369 if (*iretry) {
370 *iretry -= 1;
371 ret = cio_clear(sch);
372 return (ret == 0) ? -EBUSY : ret;
373 }
374 /* Function was unsuccessful */
375 return -EIO;
376 }
377 EXPORT_SYMBOL_GPL(cio_cancel_halt_clear);
378
cio_apply_config(struct subchannel * sch,struct schib * schib)379 static void cio_apply_config(struct subchannel *sch, struct schib *schib)
380 {
381 schib->pmcw.intparm = sch->config.intparm;
382 schib->pmcw.mbi = sch->config.mbi;
383 schib->pmcw.isc = sch->config.isc;
384 schib->pmcw.ena = sch->config.ena;
385 schib->pmcw.mme = sch->config.mme;
386 schib->pmcw.mp = sch->config.mp;
387 schib->pmcw.csense = sch->config.csense;
388 schib->pmcw.mbfc = sch->config.mbfc;
389 if (sch->config.mbfc)
390 schib->mba = sch->config.mba;
391 }
392
cio_check_config(struct subchannel * sch,struct schib * schib)393 static int cio_check_config(struct subchannel *sch, struct schib *schib)
394 {
395 return (schib->pmcw.intparm == sch->config.intparm) &&
396 (schib->pmcw.mbi == sch->config.mbi) &&
397 (schib->pmcw.isc == sch->config.isc) &&
398 (schib->pmcw.ena == sch->config.ena) &&
399 (schib->pmcw.mme == sch->config.mme) &&
400 (schib->pmcw.mp == sch->config.mp) &&
401 (schib->pmcw.csense == sch->config.csense) &&
402 (schib->pmcw.mbfc == sch->config.mbfc) &&
403 (!sch->config.mbfc || (schib->mba == sch->config.mba));
404 }
405
406 /*
407 * cio_commit_config - apply configuration to the subchannel
408 */
cio_commit_config(struct subchannel * sch)409 int cio_commit_config(struct subchannel *sch)
410 {
411 int ccode, retry, ret = 0;
412 struct schib schib;
413 struct irb irb;
414
415 if (stsch(sch->schid, &schib) || !css_sch_is_valid(&schib))
416 return -ENODEV;
417
418 for (retry = 0; retry < 5; retry++) {
419 /* copy desired changes to local schib */
420 cio_apply_config(sch, &schib);
421 ccode = msch(sch->schid, &schib);
422 if (ccode < 0) /* -EIO if msch gets a program check. */
423 return ccode;
424 switch (ccode) {
425 case 0: /* successful */
426 if (stsch(sch->schid, &schib) ||
427 !css_sch_is_valid(&schib))
428 return -ENODEV;
429 if (cio_check_config(sch, &schib)) {
430 /* commit changes from local schib */
431 memcpy(&sch->schib, &schib, sizeof(schib));
432 return 0;
433 }
434 ret = -EAGAIN;
435 break;
436 case 1: /* status pending */
437 ret = -EBUSY;
438 if (tsch(sch->schid, &irb))
439 return ret;
440 break;
441 case 2: /* busy */
442 udelay(100); /* allow for recovery */
443 ret = -EBUSY;
444 break;
445 case 3: /* not operational */
446 return -ENODEV;
447 }
448 }
449 return ret;
450 }
451 EXPORT_SYMBOL_GPL(cio_commit_config);
452
453 /**
454 * cio_update_schib - Perform stsch and update schib if subchannel is valid.
455 * @sch: subchannel on which to perform stsch
456 * Return zero on success, -ENODEV otherwise.
457 */
cio_update_schib(struct subchannel * sch)458 int cio_update_schib(struct subchannel *sch)
459 {
460 struct schib schib;
461
462 if (stsch(sch->schid, &schib) || !css_sch_is_valid(&schib))
463 return -ENODEV;
464
465 memcpy(&sch->schib, &schib, sizeof(schib));
466 return 0;
467 }
468 EXPORT_SYMBOL_GPL(cio_update_schib);
469
470 /**
471 * cio_enable_subchannel - enable a subchannel.
472 * @sch: subchannel to be enabled
473 * @intparm: interruption parameter to set
474 */
cio_enable_subchannel(struct subchannel * sch,u32 intparm)475 int cio_enable_subchannel(struct subchannel *sch, u32 intparm)
476 {
477 int ret;
478
479 CIO_TRACE_EVENT(2, "ensch");
480 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
481
482 if (sch_is_pseudo_sch(sch))
483 return -EINVAL;
484 if (cio_update_schib(sch))
485 return -ENODEV;
486
487 sch->config.ena = 1;
488 sch->config.isc = sch->isc;
489 sch->config.intparm = intparm;
490
491 ret = cio_commit_config(sch);
492 if (ret == -EIO) {
493 /*
494 * Got a program check in msch. Try without
495 * the concurrent sense bit the next time.
496 */
497 sch->config.csense = 0;
498 ret = cio_commit_config(sch);
499 }
500 CIO_HEX_EVENT(2, &ret, sizeof(ret));
501 return ret;
502 }
503 EXPORT_SYMBOL_GPL(cio_enable_subchannel);
504
505 /**
506 * cio_disable_subchannel - disable a subchannel.
507 * @sch: subchannel to disable
508 */
cio_disable_subchannel(struct subchannel * sch)509 int cio_disable_subchannel(struct subchannel *sch)
510 {
511 int ret;
512
513 CIO_TRACE_EVENT(2, "dissch");
514 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
515
516 if (sch_is_pseudo_sch(sch))
517 return 0;
518 if (cio_update_schib(sch))
519 return -ENODEV;
520
521 sch->config.ena = 0;
522 ret = cio_commit_config(sch);
523
524 CIO_HEX_EVENT(2, &ret, sizeof(ret));
525 return ret;
526 }
527 EXPORT_SYMBOL_GPL(cio_disable_subchannel);
528
529 /*
530 * do_cio_interrupt() handles all normal I/O device IRQ's
531 */
do_cio_interrupt(int irq,void * dummy)532 static irqreturn_t do_cio_interrupt(int irq, void *dummy)
533 {
534 struct tpi_info *tpi_info;
535 struct subchannel *sch;
536 struct irb *irb;
537
538 set_cpu_flag(CIF_NOHZ_DELAY);
539 tpi_info = &get_irq_regs()->tpi_info;
540 trace_s390_cio_interrupt(tpi_info);
541 irb = this_cpu_ptr(&cio_irb);
542 sch = (struct subchannel *)(unsigned long) tpi_info->intparm;
543 if (!sch) {
544 /* Clear pending interrupt condition. */
545 inc_irq_stat(IRQIO_CIO);
546 tsch(tpi_info->schid, irb);
547 return IRQ_HANDLED;
548 }
549 spin_lock(sch->lock);
550 /* Store interrupt response block to lowcore. */
551 if (tsch(tpi_info->schid, irb) == 0) {
552 /* Keep subchannel information word up to date. */
553 memcpy (&sch->schib.scsw, &irb->scsw, sizeof (irb->scsw));
554 /* Call interrupt handler if there is one. */
555 if (sch->driver && sch->driver->irq)
556 sch->driver->irq(sch);
557 else
558 inc_irq_stat(IRQIO_CIO);
559 } else
560 inc_irq_stat(IRQIO_CIO);
561 spin_unlock(sch->lock);
562
563 return IRQ_HANDLED;
564 }
565
init_cio_interrupts(void)566 void __init init_cio_interrupts(void)
567 {
568 irq_set_chip_and_handler(IO_INTERRUPT,
569 &dummy_irq_chip, handle_percpu_irq);
570 if (request_irq(IO_INTERRUPT, do_cio_interrupt, 0, "I/O", NULL))
571 panic("Failed to register I/O interrupt\n");
572 }
573
574 #ifdef CONFIG_CCW_CONSOLE
575 static struct subchannel *console_sch;
576 static struct lock_class_key console_sch_key;
577
578 /*
579 * Use cio_tsch to update the subchannel status and call the interrupt handler
580 * if status had been pending. Called with the subchannel's lock held.
581 */
cio_tsch(struct subchannel * sch)582 void cio_tsch(struct subchannel *sch)
583 {
584 struct irb *irb;
585 int irq_context;
586
587 irb = this_cpu_ptr(&cio_irb);
588 /* Store interrupt response block to lowcore. */
589 if (tsch(sch->schid, irb) != 0)
590 /* Not status pending or not operational. */
591 return;
592 memcpy(&sch->schib.scsw, &irb->scsw, sizeof(union scsw));
593 /* Call interrupt handler with updated status. */
594 irq_context = in_interrupt();
595 if (!irq_context) {
596 local_bh_disable();
597 irq_enter();
598 }
599 kstat_incr_irq_this_cpu(IO_INTERRUPT);
600 if (sch->driver && sch->driver->irq)
601 sch->driver->irq(sch);
602 else
603 inc_irq_stat(IRQIO_CIO);
604 if (!irq_context) {
605 irq_exit();
606 _local_bh_enable();
607 }
608 }
609
cio_test_for_console(struct subchannel_id schid,void * data)610 static int cio_test_for_console(struct subchannel_id schid, void *data)
611 {
612 struct schib schib;
613
614 if (stsch(schid, &schib) != 0)
615 return -ENXIO;
616 if ((schib.pmcw.st == SUBCHANNEL_TYPE_IO) && schib.pmcw.dnv &&
617 (schib.pmcw.dev == console_devno)) {
618 console_irq = schid.sch_no;
619 return 1; /* found */
620 }
621 return 0;
622 }
623
cio_get_console_sch_no(void)624 static int cio_get_console_sch_no(void)
625 {
626 struct subchannel_id schid;
627 struct schib schib;
628
629 init_subchannel_id(&schid);
630 if (console_irq != -1) {
631 /* VM provided us with the irq number of the console. */
632 schid.sch_no = console_irq;
633 if (stsch(schid, &schib) != 0 ||
634 (schib.pmcw.st != SUBCHANNEL_TYPE_IO) || !schib.pmcw.dnv)
635 return -1;
636 console_devno = schib.pmcw.dev;
637 } else if (console_devno != -1) {
638 /* At least the console device number is known. */
639 for_each_subchannel(cio_test_for_console, NULL);
640 }
641 return console_irq;
642 }
643
cio_probe_console(void)644 struct subchannel *cio_probe_console(void)
645 {
646 struct subchannel_id schid;
647 struct subchannel *sch;
648 struct schib schib;
649 int sch_no, ret;
650
651 sch_no = cio_get_console_sch_no();
652 if (sch_no == -1) {
653 pr_warn("No CCW console was found\n");
654 return ERR_PTR(-ENODEV);
655 }
656 init_subchannel_id(&schid);
657 schid.sch_no = sch_no;
658 ret = stsch(schid, &schib);
659 if (ret)
660 return ERR_PTR(-ENODEV);
661
662 sch = css_alloc_subchannel(schid, &schib);
663 if (IS_ERR(sch))
664 return sch;
665
666 lockdep_set_class(sch->lock, &console_sch_key);
667 isc_register(CONSOLE_ISC);
668 sch->config.isc = CONSOLE_ISC;
669 sch->config.intparm = (u32)(addr_t)sch;
670 ret = cio_commit_config(sch);
671 if (ret) {
672 isc_unregister(CONSOLE_ISC);
673 put_device(&sch->dev);
674 return ERR_PTR(ret);
675 }
676 console_sch = sch;
677 return sch;
678 }
679
cio_is_console(struct subchannel_id schid)680 int cio_is_console(struct subchannel_id schid)
681 {
682 if (!console_sch)
683 return 0;
684 return schid_equal(&schid, &console_sch->schid);
685 }
686
cio_register_early_subchannels(void)687 void cio_register_early_subchannels(void)
688 {
689 int ret;
690
691 if (!console_sch)
692 return;
693
694 ret = css_register_subchannel(console_sch);
695 if (ret)
696 put_device(&console_sch->dev);
697 }
698 #endif /* CONFIG_CCW_CONSOLE */
699
700 /**
701 * cio_tm_start_key - perform start function
702 * @sch: subchannel on which to perform the start function
703 * @tcw: transport-command word to be started
704 * @lpm: mask of paths to use
705 * @key: storage key to use for storage access
706 *
707 * Start the tcw on the given subchannel. Return zero on success, non-zero
708 * otherwise.
709 */
cio_tm_start_key(struct subchannel * sch,struct tcw * tcw,u8 lpm,u8 key)710 int cio_tm_start_key(struct subchannel *sch, struct tcw *tcw, u8 lpm, u8 key)
711 {
712 int cc;
713 union orb *orb = &to_io_private(sch)->orb;
714
715 memset(orb, 0, sizeof(union orb));
716 orb->tm.intparm = (u32) (addr_t) sch;
717 orb->tm.key = key >> 4;
718 orb->tm.b = 1;
719 orb->tm.lpm = lpm ? lpm : sch->lpm;
720 orb->tm.tcw = (u32) (addr_t) tcw;
721 cc = ssch(sch->schid, orb);
722 switch (cc) {
723 case 0:
724 return 0;
725 case 1:
726 case 2:
727 return -EBUSY;
728 default:
729 return cio_start_handle_notoper(sch, lpm);
730 }
731 }
732 EXPORT_SYMBOL_GPL(cio_tm_start_key);
733
734 /**
735 * cio_tm_intrg - perform interrogate function
736 * @sch: subchannel on which to perform the interrogate function
737 *
738 * If the specified subchannel is running in transport-mode, perform the
739 * interrogate function. Return zero on success, non-zero otherwie.
740 */
cio_tm_intrg(struct subchannel * sch)741 int cio_tm_intrg(struct subchannel *sch)
742 {
743 int cc;
744
745 if (!to_io_private(sch)->orb.tm.b)
746 return -EINVAL;
747 cc = xsch(sch->schid);
748 switch (cc) {
749 case 0:
750 case 2:
751 return 0;
752 case 1:
753 return -EBUSY;
754 default:
755 return -ENODEV;
756 }
757 }
758 EXPORT_SYMBOL_GPL(cio_tm_intrg);
759