xref: /openbmc/qemu/hw/s390x/css.c (revision b45c03f5)
1 /*
2  * Channel subsystem base support.
3  *
4  * Copyright 2012 IBM Corp.
5  * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
6  *
7  * This work is licensed under the terms of the GNU GPL, version 2 or (at
8  * your option) any later version. See the COPYING file in the top-level
9  * directory.
10  */
11 
12 #include <hw/qdev.h>
13 #include "qemu/bitops.h"
14 #include "exec/address-spaces.h"
15 #include "cpu.h"
16 #include "ioinst.h"
17 #include "css.h"
18 #include "trace.h"
19 #include "hw/s390x/s390_flic.h"
20 
21 typedef struct CrwContainer {
22     CRW crw;
23     QTAILQ_ENTRY(CrwContainer) sibling;
24 } CrwContainer;
25 
26 typedef struct ChpInfo {
27     uint8_t in_use;
28     uint8_t type;
29     uint8_t is_virtual;
30 } ChpInfo;
31 
32 typedef struct SubchSet {
33     SubchDev *sch[MAX_SCHID + 1];
34     unsigned long schids_used[BITS_TO_LONGS(MAX_SCHID + 1)];
35     unsigned long devnos_used[BITS_TO_LONGS(MAX_SCHID + 1)];
36 } SubchSet;
37 
38 typedef struct CssImage {
39     SubchSet *sch_set[MAX_SSID + 1];
40     ChpInfo chpids[MAX_CHPID + 1];
41 } CssImage;
42 
43 typedef struct IoAdapter {
44     uint32_t id;
45     uint8_t type;
46     uint8_t isc;
47     QTAILQ_ENTRY(IoAdapter) sibling;
48 } IoAdapter;
49 
50 typedef struct ChannelSubSys {
51     QTAILQ_HEAD(, CrwContainer) pending_crws;
52     bool do_crw_mchk;
53     bool crws_lost;
54     uint8_t max_cssid;
55     uint8_t max_ssid;
56     bool chnmon_active;
57     uint64_t chnmon_area;
58     CssImage *css[MAX_CSSID + 1];
59     uint8_t default_cssid;
60     QTAILQ_HEAD(, IoAdapter) io_adapters;
61 } ChannelSubSys;
62 
63 static ChannelSubSys *channel_subsys;
64 
65 int css_create_css_image(uint8_t cssid, bool default_image)
66 {
67     trace_css_new_image(cssid, default_image ? "(default)" : "");
68     if (cssid > MAX_CSSID) {
69         return -EINVAL;
70     }
71     if (channel_subsys->css[cssid]) {
72         return -EBUSY;
73     }
74     channel_subsys->css[cssid] = g_malloc0(sizeof(CssImage));
75     if (default_image) {
76         channel_subsys->default_cssid = cssid;
77     }
78     return 0;
79 }
80 
81 int css_register_io_adapter(uint8_t type, uint8_t isc, bool swap,
82                             bool maskable, uint32_t *id)
83 {
84     IoAdapter *adapter;
85     bool found = false;
86     int ret;
87     S390FLICState *fs = s390_get_flic();
88     S390FLICStateClass *fsc = S390_FLIC_COMMON_GET_CLASS(fs);
89 
90     *id = 0;
91     QTAILQ_FOREACH(adapter, &channel_subsys->io_adapters, sibling) {
92         if ((adapter->type == type) && (adapter->isc == isc)) {
93             *id = adapter->id;
94             found = true;
95             ret = 0;
96             break;
97         }
98         if (adapter->id >= *id) {
99             *id = adapter->id + 1;
100         }
101     }
102     if (found) {
103         goto out;
104     }
105     adapter = g_new0(IoAdapter, 1);
106     ret = fsc->register_io_adapter(fs, *id, isc, swap, maskable);
107     if (ret == 0) {
108         adapter->id = *id;
109         adapter->isc = isc;
110         adapter->type = type;
111         QTAILQ_INSERT_TAIL(&channel_subsys->io_adapters, adapter, sibling);
112     } else {
113         g_free(adapter);
114         fprintf(stderr, "Unexpected error %d when registering adapter %d\n",
115                 ret, *id);
116     }
117 out:
118     return ret;
119 }
120 
121 uint16_t css_build_subchannel_id(SubchDev *sch)
122 {
123     if (channel_subsys->max_cssid > 0) {
124         return (sch->cssid << 8) | (1 << 3) | (sch->ssid << 1) | 1;
125     }
126     return (sch->ssid << 1) | 1;
127 }
128 
129 static void css_inject_io_interrupt(SubchDev *sch)
130 {
131     uint8_t isc = (sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ISC) >> 11;
132 
133     trace_css_io_interrupt(sch->cssid, sch->ssid, sch->schid,
134                            sch->curr_status.pmcw.intparm, isc, "");
135     s390_io_interrupt(css_build_subchannel_id(sch),
136                       sch->schid,
137                       sch->curr_status.pmcw.intparm,
138                       isc << 27);
139 }
140 
141 void css_conditional_io_interrupt(SubchDev *sch)
142 {
143     /*
144      * If the subchannel is not currently status pending, make it pending
145      * with alert status.
146      */
147     if (!(sch->curr_status.scsw.ctrl & SCSW_STCTL_STATUS_PEND)) {
148         uint8_t isc = (sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ISC) >> 11;
149 
150         trace_css_io_interrupt(sch->cssid, sch->ssid, sch->schid,
151                                sch->curr_status.pmcw.intparm, isc,
152                                "(unsolicited)");
153         sch->curr_status.scsw.ctrl &= ~SCSW_CTRL_MASK_STCTL;
154         sch->curr_status.scsw.ctrl |=
155             SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
156         /* Inject an I/O interrupt. */
157         s390_io_interrupt(css_build_subchannel_id(sch),
158                           sch->schid,
159                           sch->curr_status.pmcw.intparm,
160                           isc << 27);
161     }
162 }
163 
164 void css_adapter_interrupt(uint8_t isc)
165 {
166     uint32_t io_int_word = (isc << 27) | IO_INT_WORD_AI;
167 
168     trace_css_adapter_interrupt(isc);
169     s390_io_interrupt(0, 0, 0, io_int_word);
170 }
171 
172 static void sch_handle_clear_func(SubchDev *sch)
173 {
174     PMCW *p = &sch->curr_status.pmcw;
175     SCSW *s = &sch->curr_status.scsw;
176     int path;
177 
178     /* Path management: In our simple css, we always choose the only path. */
179     path = 0x80;
180 
181     /* Reset values prior to 'issuing the clear signal'. */
182     p->lpum = 0;
183     p->pom = 0xff;
184     s->flags &= ~SCSW_FLAGS_MASK_PNO;
185 
186     /* We always 'attempt to issue the clear signal', and we always succeed. */
187     sch->channel_prog = 0x0;
188     sch->last_cmd_valid = false;
189     s->ctrl &= ~SCSW_ACTL_CLEAR_PEND;
190     s->ctrl |= SCSW_STCTL_STATUS_PEND;
191 
192     s->dstat = 0;
193     s->cstat = 0;
194     p->lpum = path;
195 
196 }
197 
198 static void sch_handle_halt_func(SubchDev *sch)
199 {
200 
201     PMCW *p = &sch->curr_status.pmcw;
202     SCSW *s = &sch->curr_status.scsw;
203     hwaddr curr_ccw = sch->channel_prog;
204     int path;
205 
206     /* Path management: In our simple css, we always choose the only path. */
207     path = 0x80;
208 
209     /* We always 'attempt to issue the halt signal', and we always succeed. */
210     sch->channel_prog = 0x0;
211     sch->last_cmd_valid = false;
212     s->ctrl &= ~SCSW_ACTL_HALT_PEND;
213     s->ctrl |= SCSW_STCTL_STATUS_PEND;
214 
215     if ((s->ctrl & (SCSW_ACTL_SUBCH_ACTIVE | SCSW_ACTL_DEVICE_ACTIVE)) ||
216         !((s->ctrl & SCSW_ACTL_START_PEND) ||
217           (s->ctrl & SCSW_ACTL_SUSP))) {
218         s->dstat = SCSW_DSTAT_DEVICE_END;
219     }
220     if ((s->ctrl & (SCSW_ACTL_SUBCH_ACTIVE | SCSW_ACTL_DEVICE_ACTIVE)) ||
221         (s->ctrl & SCSW_ACTL_SUSP)) {
222         s->cpa = curr_ccw + 8;
223     }
224     s->cstat = 0;
225     p->lpum = path;
226 
227 }
228 
229 static void copy_sense_id_to_guest(SenseId *dest, SenseId *src)
230 {
231     int i;
232 
233     dest->reserved = src->reserved;
234     dest->cu_type = cpu_to_be16(src->cu_type);
235     dest->cu_model = src->cu_model;
236     dest->dev_type = cpu_to_be16(src->dev_type);
237     dest->dev_model = src->dev_model;
238     dest->unused = src->unused;
239     for (i = 0; i < ARRAY_SIZE(dest->ciw); i++) {
240         dest->ciw[i].type = src->ciw[i].type;
241         dest->ciw[i].command = src->ciw[i].command;
242         dest->ciw[i].count = cpu_to_be16(src->ciw[i].count);
243     }
244 }
245 
246 static CCW1 copy_ccw_from_guest(hwaddr addr, bool fmt1)
247 {
248     CCW0 tmp0;
249     CCW1 tmp1;
250     CCW1 ret;
251 
252     if (fmt1) {
253         cpu_physical_memory_read(addr, &tmp1, sizeof(tmp1));
254         ret.cmd_code = tmp1.cmd_code;
255         ret.flags = tmp1.flags;
256         ret.count = be16_to_cpu(tmp1.count);
257         ret.cda = be32_to_cpu(tmp1.cda);
258     } else {
259         cpu_physical_memory_read(addr, &tmp0, sizeof(tmp0));
260         ret.cmd_code = tmp0.cmd_code;
261         ret.flags = tmp0.flags;
262         ret.count = be16_to_cpu(tmp0.count);
263         ret.cda = be16_to_cpu(tmp0.cda1) | (tmp0.cda0 << 16);
264     }
265     return ret;
266 }
267 
268 static int css_interpret_ccw(SubchDev *sch, hwaddr ccw_addr)
269 {
270     int ret;
271     bool check_len;
272     int len;
273     CCW1 ccw;
274 
275     if (!ccw_addr) {
276         return -EIO;
277     }
278 
279     /* Translate everything to format-1 ccws - the information is the same. */
280     ccw = copy_ccw_from_guest(ccw_addr, sch->ccw_fmt_1);
281 
282     /* Check for invalid command codes. */
283     if ((ccw.cmd_code & 0x0f) == 0) {
284         return -EINVAL;
285     }
286     if (((ccw.cmd_code & 0x0f) == CCW_CMD_TIC) &&
287         ((ccw.cmd_code & 0xf0) != 0)) {
288         return -EINVAL;
289     }
290 
291     if (ccw.flags & CCW_FLAG_SUSPEND) {
292         return -EINPROGRESS;
293     }
294 
295     check_len = !((ccw.flags & CCW_FLAG_SLI) && !(ccw.flags & CCW_FLAG_DC));
296 
297     if (!ccw.cda) {
298         if (sch->ccw_no_data_cnt == 255) {
299             return -EINVAL;
300         }
301         sch->ccw_no_data_cnt++;
302     }
303 
304     /* Look at the command. */
305     switch (ccw.cmd_code) {
306     case CCW_CMD_NOOP:
307         /* Nothing to do. */
308         ret = 0;
309         break;
310     case CCW_CMD_BASIC_SENSE:
311         if (check_len) {
312             if (ccw.count != sizeof(sch->sense_data)) {
313                 ret = -EINVAL;
314                 break;
315             }
316         }
317         len = MIN(ccw.count, sizeof(sch->sense_data));
318         cpu_physical_memory_write(ccw.cda, sch->sense_data, len);
319         sch->curr_status.scsw.count = ccw.count - len;
320         memset(sch->sense_data, 0, sizeof(sch->sense_data));
321         ret = 0;
322         break;
323     case CCW_CMD_SENSE_ID:
324     {
325         SenseId sense_id;
326 
327         copy_sense_id_to_guest(&sense_id, &sch->id);
328         /* Sense ID information is device specific. */
329         if (check_len) {
330             if (ccw.count != sizeof(sense_id)) {
331                 ret = -EINVAL;
332                 break;
333             }
334         }
335         len = MIN(ccw.count, sizeof(sense_id));
336         /*
337          * Only indicate 0xff in the first sense byte if we actually
338          * have enough place to store at least bytes 0-3.
339          */
340         if (len >= 4) {
341             sense_id.reserved = 0xff;
342         } else {
343             sense_id.reserved = 0;
344         }
345         cpu_physical_memory_write(ccw.cda, &sense_id, len);
346         sch->curr_status.scsw.count = ccw.count - len;
347         ret = 0;
348         break;
349     }
350     case CCW_CMD_TIC:
351         if (sch->last_cmd_valid && (sch->last_cmd.cmd_code == CCW_CMD_TIC)) {
352             ret = -EINVAL;
353             break;
354         }
355         if (ccw.flags & (CCW_FLAG_CC | CCW_FLAG_DC)) {
356             ret = -EINVAL;
357             break;
358         }
359         sch->channel_prog = ccw.cda;
360         ret = -EAGAIN;
361         break;
362     default:
363         if (sch->ccw_cb) {
364             /* Handle device specific commands. */
365             ret = sch->ccw_cb(sch, ccw);
366         } else {
367             ret = -ENOSYS;
368         }
369         break;
370     }
371     sch->last_cmd = ccw;
372     sch->last_cmd_valid = true;
373     if (ret == 0) {
374         if (ccw.flags & CCW_FLAG_CC) {
375             sch->channel_prog += 8;
376             ret = -EAGAIN;
377         }
378     }
379 
380     return ret;
381 }
382 
383 static void sch_handle_start_func(SubchDev *sch, ORB *orb)
384 {
385 
386     PMCW *p = &sch->curr_status.pmcw;
387     SCSW *s = &sch->curr_status.scsw;
388     int path;
389     int ret;
390 
391     /* Path management: In our simple css, we always choose the only path. */
392     path = 0x80;
393 
394     if (!(s->ctrl & SCSW_ACTL_SUSP)) {
395         /* Look at the orb and try to execute the channel program. */
396         assert(orb != NULL); /* resume does not pass an orb */
397         p->intparm = orb->intparm;
398         if (!(orb->lpm & path)) {
399             /* Generate a deferred cc 3 condition. */
400             s->flags |= SCSW_FLAGS_MASK_CC;
401             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
402             s->ctrl |= (SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND);
403             return;
404         }
405         sch->ccw_fmt_1 = !!(orb->ctrl0 & ORB_CTRL0_MASK_FMT);
406         sch->ccw_no_data_cnt = 0;
407     } else {
408         s->ctrl &= ~(SCSW_ACTL_SUSP | SCSW_ACTL_RESUME_PEND);
409     }
410     sch->last_cmd_valid = false;
411     do {
412         ret = css_interpret_ccw(sch, sch->channel_prog);
413         switch (ret) {
414         case -EAGAIN:
415             /* ccw chain, continue processing */
416             break;
417         case 0:
418             /* success */
419             s->ctrl &= ~SCSW_ACTL_START_PEND;
420             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
421             s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
422                     SCSW_STCTL_STATUS_PEND;
423             s->dstat = SCSW_DSTAT_CHANNEL_END | SCSW_DSTAT_DEVICE_END;
424             s->cpa = sch->channel_prog + 8;
425             break;
426         case -ENOSYS:
427             /* unsupported command, generate unit check (command reject) */
428             s->ctrl &= ~SCSW_ACTL_START_PEND;
429             s->dstat = SCSW_DSTAT_UNIT_CHECK;
430             /* Set sense bit 0 in ecw0. */
431             sch->sense_data[0] = 0x80;
432             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
433             s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
434                     SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
435             s->cpa = sch->channel_prog + 8;
436             break;
437         case -EFAULT:
438             /* memory problem, generate channel data check */
439             s->ctrl &= ~SCSW_ACTL_START_PEND;
440             s->cstat = SCSW_CSTAT_DATA_CHECK;
441             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
442             s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
443                     SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
444             s->cpa = sch->channel_prog + 8;
445             break;
446         case -EBUSY:
447             /* subchannel busy, generate deferred cc 1 */
448             s->flags &= ~SCSW_FLAGS_MASK_CC;
449             s->flags |= (1 << 8);
450             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
451             s->ctrl |= SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
452             break;
453         case -EINPROGRESS:
454             /* channel program has been suspended */
455             s->ctrl &= ~SCSW_ACTL_START_PEND;
456             s->ctrl |= SCSW_ACTL_SUSP;
457             break;
458         default:
459             /* error, generate channel program check */
460             s->ctrl &= ~SCSW_ACTL_START_PEND;
461             s->cstat = SCSW_CSTAT_PROG_CHECK;
462             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
463             s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
464                     SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
465             s->cpa = sch->channel_prog + 8;
466             break;
467         }
468     } while (ret == -EAGAIN);
469 
470 }
471 
472 /*
473  * On real machines, this would run asynchronously to the main vcpus.
474  * We might want to make some parts of the ssch handling (interpreting
475  * read/writes) asynchronous later on if we start supporting more than
476  * our current very simple devices.
477  */
478 static void do_subchannel_work(SubchDev *sch, ORB *orb)
479 {
480 
481     SCSW *s = &sch->curr_status.scsw;
482 
483     if (s->ctrl & SCSW_FCTL_CLEAR_FUNC) {
484         sch_handle_clear_func(sch);
485     } else if (s->ctrl & SCSW_FCTL_HALT_FUNC) {
486         sch_handle_halt_func(sch);
487     } else if (s->ctrl & SCSW_FCTL_START_FUNC) {
488         sch_handle_start_func(sch, orb);
489     } else {
490         /* Cannot happen. */
491         return;
492     }
493     css_inject_io_interrupt(sch);
494 }
495 
496 static void copy_pmcw_to_guest(PMCW *dest, const PMCW *src)
497 {
498     int i;
499 
500     dest->intparm = cpu_to_be32(src->intparm);
501     dest->flags = cpu_to_be16(src->flags);
502     dest->devno = cpu_to_be16(src->devno);
503     dest->lpm = src->lpm;
504     dest->pnom = src->pnom;
505     dest->lpum = src->lpum;
506     dest->pim = src->pim;
507     dest->mbi = cpu_to_be16(src->mbi);
508     dest->pom = src->pom;
509     dest->pam = src->pam;
510     for (i = 0; i < ARRAY_SIZE(dest->chpid); i++) {
511         dest->chpid[i] = src->chpid[i];
512     }
513     dest->chars = cpu_to_be32(src->chars);
514 }
515 
516 static void copy_scsw_to_guest(SCSW *dest, const SCSW *src)
517 {
518     dest->flags = cpu_to_be16(src->flags);
519     dest->ctrl = cpu_to_be16(src->ctrl);
520     dest->cpa = cpu_to_be32(src->cpa);
521     dest->dstat = src->dstat;
522     dest->cstat = src->cstat;
523     dest->count = cpu_to_be16(src->count);
524 }
525 
526 static void copy_schib_to_guest(SCHIB *dest, const SCHIB *src)
527 {
528     int i;
529 
530     copy_pmcw_to_guest(&dest->pmcw, &src->pmcw);
531     copy_scsw_to_guest(&dest->scsw, &src->scsw);
532     dest->mba = cpu_to_be64(src->mba);
533     for (i = 0; i < ARRAY_SIZE(dest->mda); i++) {
534         dest->mda[i] = src->mda[i];
535     }
536 }
537 
538 int css_do_stsch(SubchDev *sch, SCHIB *schib)
539 {
540     /* Use current status. */
541     copy_schib_to_guest(schib, &sch->curr_status);
542     return 0;
543 }
544 
545 static void copy_pmcw_from_guest(PMCW *dest, const PMCW *src)
546 {
547     int i;
548 
549     dest->intparm = be32_to_cpu(src->intparm);
550     dest->flags = be16_to_cpu(src->flags);
551     dest->devno = be16_to_cpu(src->devno);
552     dest->lpm = src->lpm;
553     dest->pnom = src->pnom;
554     dest->lpum = src->lpum;
555     dest->pim = src->pim;
556     dest->mbi = be16_to_cpu(src->mbi);
557     dest->pom = src->pom;
558     dest->pam = src->pam;
559     for (i = 0; i < ARRAY_SIZE(dest->chpid); i++) {
560         dest->chpid[i] = src->chpid[i];
561     }
562     dest->chars = be32_to_cpu(src->chars);
563 }
564 
565 static void copy_scsw_from_guest(SCSW *dest, const SCSW *src)
566 {
567     dest->flags = be16_to_cpu(src->flags);
568     dest->ctrl = be16_to_cpu(src->ctrl);
569     dest->cpa = be32_to_cpu(src->cpa);
570     dest->dstat = src->dstat;
571     dest->cstat = src->cstat;
572     dest->count = be16_to_cpu(src->count);
573 }
574 
575 static void copy_schib_from_guest(SCHIB *dest, const SCHIB *src)
576 {
577     int i;
578 
579     copy_pmcw_from_guest(&dest->pmcw, &src->pmcw);
580     copy_scsw_from_guest(&dest->scsw, &src->scsw);
581     dest->mba = be64_to_cpu(src->mba);
582     for (i = 0; i < ARRAY_SIZE(dest->mda); i++) {
583         dest->mda[i] = src->mda[i];
584     }
585 }
586 
587 int css_do_msch(SubchDev *sch, const SCHIB *orig_schib)
588 {
589     SCSW *s = &sch->curr_status.scsw;
590     PMCW *p = &sch->curr_status.pmcw;
591     uint16_t oldflags;
592     int ret;
593     SCHIB schib;
594 
595     if (!(sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_DNV)) {
596         ret = 0;
597         goto out;
598     }
599 
600     if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
601         ret = -EINPROGRESS;
602         goto out;
603     }
604 
605     if (s->ctrl &
606         (SCSW_FCTL_START_FUNC|SCSW_FCTL_HALT_FUNC|SCSW_FCTL_CLEAR_FUNC)) {
607         ret = -EBUSY;
608         goto out;
609     }
610 
611     copy_schib_from_guest(&schib, orig_schib);
612     /* Only update the program-modifiable fields. */
613     p->intparm = schib.pmcw.intparm;
614     oldflags = p->flags;
615     p->flags &= ~(PMCW_FLAGS_MASK_ISC | PMCW_FLAGS_MASK_ENA |
616                   PMCW_FLAGS_MASK_LM | PMCW_FLAGS_MASK_MME |
617                   PMCW_FLAGS_MASK_MP);
618     p->flags |= schib.pmcw.flags &
619             (PMCW_FLAGS_MASK_ISC | PMCW_FLAGS_MASK_ENA |
620              PMCW_FLAGS_MASK_LM | PMCW_FLAGS_MASK_MME |
621              PMCW_FLAGS_MASK_MP);
622     p->lpm = schib.pmcw.lpm;
623     p->mbi = schib.pmcw.mbi;
624     p->pom = schib.pmcw.pom;
625     p->chars &= ~(PMCW_CHARS_MASK_MBFC | PMCW_CHARS_MASK_CSENSE);
626     p->chars |= schib.pmcw.chars &
627             (PMCW_CHARS_MASK_MBFC | PMCW_CHARS_MASK_CSENSE);
628     sch->curr_status.mba = schib.mba;
629 
630     /* Has the channel been disabled? */
631     if (sch->disable_cb && (oldflags & PMCW_FLAGS_MASK_ENA) != 0
632         && (p->flags & PMCW_FLAGS_MASK_ENA) == 0) {
633         sch->disable_cb(sch);
634     }
635 
636     ret = 0;
637 
638 out:
639     return ret;
640 }
641 
642 int css_do_xsch(SubchDev *sch)
643 {
644     SCSW *s = &sch->curr_status.scsw;
645     PMCW *p = &sch->curr_status.pmcw;
646     int ret;
647 
648     if (!(p->flags & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA))) {
649         ret = -ENODEV;
650         goto out;
651     }
652 
653     if (!(s->ctrl & SCSW_CTRL_MASK_FCTL) ||
654         ((s->ctrl & SCSW_CTRL_MASK_FCTL) != SCSW_FCTL_START_FUNC) ||
655         (!(s->ctrl &
656            (SCSW_ACTL_RESUME_PEND | SCSW_ACTL_START_PEND | SCSW_ACTL_SUSP))) ||
657         (s->ctrl & SCSW_ACTL_SUBCH_ACTIVE)) {
658         ret = -EINPROGRESS;
659         goto out;
660     }
661 
662     if (s->ctrl & SCSW_CTRL_MASK_STCTL) {
663         ret = -EBUSY;
664         goto out;
665     }
666 
667     /* Cancel the current operation. */
668     s->ctrl &= ~(SCSW_FCTL_START_FUNC |
669                  SCSW_ACTL_RESUME_PEND |
670                  SCSW_ACTL_START_PEND |
671                  SCSW_ACTL_SUSP);
672     sch->channel_prog = 0x0;
673     sch->last_cmd_valid = false;
674     s->dstat = 0;
675     s->cstat = 0;
676     ret = 0;
677 
678 out:
679     return ret;
680 }
681 
682 int css_do_csch(SubchDev *sch)
683 {
684     SCSW *s = &sch->curr_status.scsw;
685     PMCW *p = &sch->curr_status.pmcw;
686     int ret;
687 
688     if (!(p->flags & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA))) {
689         ret = -ENODEV;
690         goto out;
691     }
692 
693     /* Trigger the clear function. */
694     s->ctrl &= ~(SCSW_CTRL_MASK_FCTL | SCSW_CTRL_MASK_ACTL);
695     s->ctrl |= SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_CLEAR_FUNC;
696 
697     do_subchannel_work(sch, NULL);
698     ret = 0;
699 
700 out:
701     return ret;
702 }
703 
704 int css_do_hsch(SubchDev *sch)
705 {
706     SCSW *s = &sch->curr_status.scsw;
707     PMCW *p = &sch->curr_status.pmcw;
708     int ret;
709 
710     if (!(p->flags & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA))) {
711         ret = -ENODEV;
712         goto out;
713     }
714 
715     if (((s->ctrl & SCSW_CTRL_MASK_STCTL) == SCSW_STCTL_STATUS_PEND) ||
716         (s->ctrl & (SCSW_STCTL_PRIMARY |
717                     SCSW_STCTL_SECONDARY |
718                     SCSW_STCTL_ALERT))) {
719         ret = -EINPROGRESS;
720         goto out;
721     }
722 
723     if (s->ctrl & (SCSW_FCTL_HALT_FUNC | SCSW_FCTL_CLEAR_FUNC)) {
724         ret = -EBUSY;
725         goto out;
726     }
727 
728     /* Trigger the halt function. */
729     s->ctrl |= SCSW_FCTL_HALT_FUNC;
730     s->ctrl &= ~SCSW_FCTL_START_FUNC;
731     if (((s->ctrl & SCSW_CTRL_MASK_ACTL) ==
732          (SCSW_ACTL_SUBCH_ACTIVE | SCSW_ACTL_DEVICE_ACTIVE)) &&
733         ((s->ctrl & SCSW_CTRL_MASK_STCTL) == SCSW_STCTL_INTERMEDIATE)) {
734         s->ctrl &= ~SCSW_STCTL_STATUS_PEND;
735     }
736     s->ctrl |= SCSW_ACTL_HALT_PEND;
737 
738     do_subchannel_work(sch, NULL);
739     ret = 0;
740 
741 out:
742     return ret;
743 }
744 
745 static void css_update_chnmon(SubchDev *sch)
746 {
747     if (!(sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_MME)) {
748         /* Not active. */
749         return;
750     }
751     /* The counter is conveniently located at the beginning of the struct. */
752     if (sch->curr_status.pmcw.chars & PMCW_CHARS_MASK_MBFC) {
753         /* Format 1, per-subchannel area. */
754         uint32_t count;
755 
756         count = address_space_ldl(&address_space_memory,
757                                   sch->curr_status.mba,
758                                   MEMTXATTRS_UNSPECIFIED,
759                                   NULL);
760         count++;
761         address_space_stl(&address_space_memory, sch->curr_status.mba, count,
762                           MEMTXATTRS_UNSPECIFIED, NULL);
763     } else {
764         /* Format 0, global area. */
765         uint32_t offset;
766         uint16_t count;
767 
768         offset = sch->curr_status.pmcw.mbi << 5;
769         count = address_space_lduw(&address_space_memory,
770                                    channel_subsys->chnmon_area + offset,
771                                    MEMTXATTRS_UNSPECIFIED,
772                                    NULL);
773         count++;
774         address_space_stw(&address_space_memory,
775                           channel_subsys->chnmon_area + offset, count,
776                           MEMTXATTRS_UNSPECIFIED, NULL);
777     }
778 }
779 
780 int css_do_ssch(SubchDev *sch, ORB *orb)
781 {
782     SCSW *s = &sch->curr_status.scsw;
783     PMCW *p = &sch->curr_status.pmcw;
784     int ret;
785 
786     if (!(p->flags & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA))) {
787         ret = -ENODEV;
788         goto out;
789     }
790 
791     if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
792         ret = -EINPROGRESS;
793         goto out;
794     }
795 
796     if (s->ctrl & (SCSW_FCTL_START_FUNC |
797                    SCSW_FCTL_HALT_FUNC |
798                    SCSW_FCTL_CLEAR_FUNC)) {
799         ret = -EBUSY;
800         goto out;
801     }
802 
803     /* If monitoring is active, update counter. */
804     if (channel_subsys->chnmon_active) {
805         css_update_chnmon(sch);
806     }
807     sch->channel_prog = orb->cpa;
808     /* Trigger the start function. */
809     s->ctrl |= (SCSW_FCTL_START_FUNC | SCSW_ACTL_START_PEND);
810     s->flags &= ~SCSW_FLAGS_MASK_PNO;
811 
812     do_subchannel_work(sch, orb);
813     ret = 0;
814 
815 out:
816     return ret;
817 }
818 
819 static void copy_irb_to_guest(IRB *dest, const IRB *src, PMCW *pmcw,
820                               int *irb_len)
821 {
822     int i;
823     uint16_t stctl = src->scsw.ctrl & SCSW_CTRL_MASK_STCTL;
824     uint16_t actl = src->scsw.ctrl & SCSW_CTRL_MASK_ACTL;
825 
826     copy_scsw_to_guest(&dest->scsw, &src->scsw);
827 
828     for (i = 0; i < ARRAY_SIZE(dest->esw); i++) {
829         dest->esw[i] = cpu_to_be32(src->esw[i]);
830     }
831     for (i = 0; i < ARRAY_SIZE(dest->ecw); i++) {
832         dest->ecw[i] = cpu_to_be32(src->ecw[i]);
833     }
834     *irb_len = sizeof(*dest) - sizeof(dest->emw);
835 
836     /* extended measurements enabled? */
837     if ((src->scsw.flags & SCSW_FLAGS_MASK_ESWF) ||
838         !(pmcw->flags & PMCW_FLAGS_MASK_TF) ||
839         !(pmcw->chars & PMCW_CHARS_MASK_XMWME)) {
840         return;
841     }
842     /* extended measurements pending? */
843     if (!(stctl & SCSW_STCTL_STATUS_PEND)) {
844         return;
845     }
846     if ((stctl & SCSW_STCTL_PRIMARY) ||
847         (stctl == SCSW_STCTL_SECONDARY) ||
848         ((stctl & SCSW_STCTL_INTERMEDIATE) && (actl & SCSW_ACTL_SUSP))) {
849         for (i = 0; i < ARRAY_SIZE(dest->emw); i++) {
850             dest->emw[i] = cpu_to_be32(src->emw[i]);
851         }
852     }
853     *irb_len = sizeof(*dest);
854 }
855 
856 int css_do_tsch_get_irb(SubchDev *sch, IRB *target_irb, int *irb_len)
857 {
858     SCSW *s = &sch->curr_status.scsw;
859     PMCW *p = &sch->curr_status.pmcw;
860     uint16_t stctl;
861     IRB irb;
862 
863     if (!(p->flags & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA))) {
864         return 3;
865     }
866 
867     stctl = s->ctrl & SCSW_CTRL_MASK_STCTL;
868 
869     /* Prepare the irb for the guest. */
870     memset(&irb, 0, sizeof(IRB));
871 
872     /* Copy scsw from current status. */
873     memcpy(&irb.scsw, s, sizeof(SCSW));
874     if (stctl & SCSW_STCTL_STATUS_PEND) {
875         if (s->cstat & (SCSW_CSTAT_DATA_CHECK |
876                         SCSW_CSTAT_CHN_CTRL_CHK |
877                         SCSW_CSTAT_INTF_CTRL_CHK)) {
878             irb.scsw.flags |= SCSW_FLAGS_MASK_ESWF;
879             irb.esw[0] = 0x04804000;
880         } else {
881             irb.esw[0] = 0x00800000;
882         }
883         /* If a unit check is pending, copy sense data. */
884         if ((s->dstat & SCSW_DSTAT_UNIT_CHECK) &&
885             (p->chars & PMCW_CHARS_MASK_CSENSE)) {
886             irb.scsw.flags |= SCSW_FLAGS_MASK_ESWF | SCSW_FLAGS_MASK_ECTL;
887             memcpy(irb.ecw, sch->sense_data, sizeof(sch->sense_data));
888             irb.esw[1] = 0x01000000 | (sizeof(sch->sense_data) << 8);
889         }
890     }
891     /* Store the irb to the guest. */
892     copy_irb_to_guest(target_irb, &irb, p, irb_len);
893 
894     return ((stctl & SCSW_STCTL_STATUS_PEND) == 0);
895 }
896 
897 void css_do_tsch_update_subch(SubchDev *sch)
898 {
899     SCSW *s = &sch->curr_status.scsw;
900     PMCW *p = &sch->curr_status.pmcw;
901     uint16_t stctl;
902     uint16_t fctl;
903     uint16_t actl;
904 
905     stctl = s->ctrl & SCSW_CTRL_MASK_STCTL;
906     fctl = s->ctrl & SCSW_CTRL_MASK_FCTL;
907     actl = s->ctrl & SCSW_CTRL_MASK_ACTL;
908 
909     /* Clear conditions on subchannel, if applicable. */
910     if (stctl & SCSW_STCTL_STATUS_PEND) {
911         s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
912         if ((stctl != (SCSW_STCTL_INTERMEDIATE | SCSW_STCTL_STATUS_PEND)) ||
913             ((fctl & SCSW_FCTL_HALT_FUNC) &&
914              (actl & SCSW_ACTL_SUSP))) {
915             s->ctrl &= ~SCSW_CTRL_MASK_FCTL;
916         }
917         if (stctl != (SCSW_STCTL_INTERMEDIATE | SCSW_STCTL_STATUS_PEND)) {
918             s->flags &= ~SCSW_FLAGS_MASK_PNO;
919             s->ctrl &= ~(SCSW_ACTL_RESUME_PEND |
920                          SCSW_ACTL_START_PEND |
921                          SCSW_ACTL_HALT_PEND |
922                          SCSW_ACTL_CLEAR_PEND |
923                          SCSW_ACTL_SUSP);
924         } else {
925             if ((actl & SCSW_ACTL_SUSP) &&
926                 (fctl & SCSW_FCTL_START_FUNC)) {
927                 s->flags &= ~SCSW_FLAGS_MASK_PNO;
928                 if (fctl & SCSW_FCTL_HALT_FUNC) {
929                     s->ctrl &= ~(SCSW_ACTL_RESUME_PEND |
930                                  SCSW_ACTL_START_PEND |
931                                  SCSW_ACTL_HALT_PEND |
932                                  SCSW_ACTL_CLEAR_PEND |
933                                  SCSW_ACTL_SUSP);
934                 } else {
935                     s->ctrl &= ~SCSW_ACTL_RESUME_PEND;
936                 }
937             }
938         }
939         /* Clear pending sense data. */
940         if (p->chars & PMCW_CHARS_MASK_CSENSE) {
941             memset(sch->sense_data, 0 , sizeof(sch->sense_data));
942         }
943     }
944 }
945 
946 static void copy_crw_to_guest(CRW *dest, const CRW *src)
947 {
948     dest->flags = cpu_to_be16(src->flags);
949     dest->rsid = cpu_to_be16(src->rsid);
950 }
951 
952 int css_do_stcrw(CRW *crw)
953 {
954     CrwContainer *crw_cont;
955     int ret;
956 
957     crw_cont = QTAILQ_FIRST(&channel_subsys->pending_crws);
958     if (crw_cont) {
959         QTAILQ_REMOVE(&channel_subsys->pending_crws, crw_cont, sibling);
960         copy_crw_to_guest(crw, &crw_cont->crw);
961         g_free(crw_cont);
962         ret = 0;
963     } else {
964         /* List was empty, turn crw machine checks on again. */
965         memset(crw, 0, sizeof(*crw));
966         channel_subsys->do_crw_mchk = true;
967         ret = 1;
968     }
969 
970     return ret;
971 }
972 
973 static void copy_crw_from_guest(CRW *dest, const CRW *src)
974 {
975     dest->flags = be16_to_cpu(src->flags);
976     dest->rsid = be16_to_cpu(src->rsid);
977 }
978 
979 void css_undo_stcrw(CRW *crw)
980 {
981     CrwContainer *crw_cont;
982 
983     crw_cont = g_try_malloc0(sizeof(CrwContainer));
984     if (!crw_cont) {
985         channel_subsys->crws_lost = true;
986         return;
987     }
988     copy_crw_from_guest(&crw_cont->crw, crw);
989 
990     QTAILQ_INSERT_HEAD(&channel_subsys->pending_crws, crw_cont, sibling);
991 }
992 
993 int css_do_tpi(IOIntCode *int_code, int lowcore)
994 {
995     /* No pending interrupts for !KVM. */
996     return 0;
997  }
998 
999 int css_collect_chp_desc(int m, uint8_t cssid, uint8_t f_chpid, uint8_t l_chpid,
1000                          int rfmt, void *buf)
1001 {
1002     int i, desc_size;
1003     uint32_t words[8];
1004     uint32_t chpid_type_word;
1005     CssImage *css;
1006 
1007     if (!m && !cssid) {
1008         css = channel_subsys->css[channel_subsys->default_cssid];
1009     } else {
1010         css = channel_subsys->css[cssid];
1011     }
1012     if (!css) {
1013         return 0;
1014     }
1015     desc_size = 0;
1016     for (i = f_chpid; i <= l_chpid; i++) {
1017         if (css->chpids[i].in_use) {
1018             chpid_type_word = 0x80000000 | (css->chpids[i].type << 8) | i;
1019             if (rfmt == 0) {
1020                 words[0] = cpu_to_be32(chpid_type_word);
1021                 words[1] = 0;
1022                 memcpy(buf + desc_size, words, 8);
1023                 desc_size += 8;
1024             } else if (rfmt == 1) {
1025                 words[0] = cpu_to_be32(chpid_type_word);
1026                 words[1] = 0;
1027                 words[2] = 0;
1028                 words[3] = 0;
1029                 words[4] = 0;
1030                 words[5] = 0;
1031                 words[6] = 0;
1032                 words[7] = 0;
1033                 memcpy(buf + desc_size, words, 32);
1034                 desc_size += 32;
1035             }
1036         }
1037     }
1038     return desc_size;
1039 }
1040 
1041 void css_do_schm(uint8_t mbk, int update, int dct, uint64_t mbo)
1042 {
1043     /* dct is currently ignored (not really meaningful for our devices) */
1044     /* TODO: Don't ignore mbk. */
1045     if (update && !channel_subsys->chnmon_active) {
1046         /* Enable measuring. */
1047         channel_subsys->chnmon_area = mbo;
1048         channel_subsys->chnmon_active = true;
1049     }
1050     if (!update && channel_subsys->chnmon_active) {
1051         /* Disable measuring. */
1052         channel_subsys->chnmon_area = 0;
1053         channel_subsys->chnmon_active = false;
1054     }
1055 }
1056 
1057 int css_do_rsch(SubchDev *sch)
1058 {
1059     SCSW *s = &sch->curr_status.scsw;
1060     PMCW *p = &sch->curr_status.pmcw;
1061     int ret;
1062 
1063     if (!(p->flags & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA))) {
1064         ret = -ENODEV;
1065         goto out;
1066     }
1067 
1068     if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
1069         ret = -EINPROGRESS;
1070         goto out;
1071     }
1072 
1073     if (((s->ctrl & SCSW_CTRL_MASK_FCTL) != SCSW_FCTL_START_FUNC) ||
1074         (s->ctrl & SCSW_ACTL_RESUME_PEND) ||
1075         (!(s->ctrl & SCSW_ACTL_SUSP))) {
1076         ret = -EINVAL;
1077         goto out;
1078     }
1079 
1080     /* If monitoring is active, update counter. */
1081     if (channel_subsys->chnmon_active) {
1082         css_update_chnmon(sch);
1083     }
1084 
1085     s->ctrl |= SCSW_ACTL_RESUME_PEND;
1086     do_subchannel_work(sch, NULL);
1087     ret = 0;
1088 
1089 out:
1090     return ret;
1091 }
1092 
1093 int css_do_rchp(uint8_t cssid, uint8_t chpid)
1094 {
1095     uint8_t real_cssid;
1096 
1097     if (cssid > channel_subsys->max_cssid) {
1098         return -EINVAL;
1099     }
1100     if (channel_subsys->max_cssid == 0) {
1101         real_cssid = channel_subsys->default_cssid;
1102     } else {
1103         real_cssid = cssid;
1104     }
1105     if (!channel_subsys->css[real_cssid]) {
1106         return -EINVAL;
1107     }
1108 
1109     if (!channel_subsys->css[real_cssid]->chpids[chpid].in_use) {
1110         return -ENODEV;
1111     }
1112 
1113     if (!channel_subsys->css[real_cssid]->chpids[chpid].is_virtual) {
1114         fprintf(stderr,
1115                 "rchp unsupported for non-virtual chpid %x.%02x!\n",
1116                 real_cssid, chpid);
1117         return -ENODEV;
1118     }
1119 
1120     /* We don't really use a channel path, so we're done here. */
1121     css_queue_crw(CRW_RSC_CHP, CRW_ERC_INIT,
1122                   channel_subsys->max_cssid > 0 ? 1 : 0, chpid);
1123     if (channel_subsys->max_cssid > 0) {
1124         css_queue_crw(CRW_RSC_CHP, CRW_ERC_INIT, 0, real_cssid << 8);
1125     }
1126     return 0;
1127 }
1128 
1129 bool css_schid_final(int m, uint8_t cssid, uint8_t ssid, uint16_t schid)
1130 {
1131     SubchSet *set;
1132     uint8_t real_cssid;
1133 
1134     real_cssid = (!m && (cssid == 0)) ? channel_subsys->default_cssid : cssid;
1135     if (real_cssid > MAX_CSSID || ssid > MAX_SSID ||
1136         !channel_subsys->css[real_cssid] ||
1137         !channel_subsys->css[real_cssid]->sch_set[ssid]) {
1138         return true;
1139     }
1140     set = channel_subsys->css[real_cssid]->sch_set[ssid];
1141     return schid > find_last_bit(set->schids_used,
1142                                  (MAX_SCHID + 1) / sizeof(unsigned long));
1143 }
1144 
1145 static int css_add_virtual_chpid(uint8_t cssid, uint8_t chpid, uint8_t type)
1146 {
1147     CssImage *css;
1148 
1149     trace_css_chpid_add(cssid, chpid, type);
1150     if (cssid > MAX_CSSID) {
1151         return -EINVAL;
1152     }
1153     css = channel_subsys->css[cssid];
1154     if (!css) {
1155         return -EINVAL;
1156     }
1157     if (css->chpids[chpid].in_use) {
1158         return -EEXIST;
1159     }
1160     css->chpids[chpid].in_use = 1;
1161     css->chpids[chpid].type = type;
1162     css->chpids[chpid].is_virtual = 1;
1163 
1164     css_generate_chp_crws(cssid, chpid);
1165 
1166     return 0;
1167 }
1168 
1169 void css_sch_build_virtual_schib(SubchDev *sch, uint8_t chpid, uint8_t type)
1170 {
1171     PMCW *p = &sch->curr_status.pmcw;
1172     SCSW *s = &sch->curr_status.scsw;
1173     int i;
1174     CssImage *css = channel_subsys->css[sch->cssid];
1175 
1176     assert(css != NULL);
1177     memset(p, 0, sizeof(PMCW));
1178     p->flags |= PMCW_FLAGS_MASK_DNV;
1179     p->devno = sch->devno;
1180     /* single path */
1181     p->pim = 0x80;
1182     p->pom = 0xff;
1183     p->pam = 0x80;
1184     p->chpid[0] = chpid;
1185     if (!css->chpids[chpid].in_use) {
1186         css_add_virtual_chpid(sch->cssid, chpid, type);
1187     }
1188 
1189     memset(s, 0, sizeof(SCSW));
1190     sch->curr_status.mba = 0;
1191     for (i = 0; i < ARRAY_SIZE(sch->curr_status.mda); i++) {
1192         sch->curr_status.mda[i] = 0;
1193     }
1194 }
1195 
1196 SubchDev *css_find_subch(uint8_t m, uint8_t cssid, uint8_t ssid, uint16_t schid)
1197 {
1198     uint8_t real_cssid;
1199 
1200     real_cssid = (!m && (cssid == 0)) ? channel_subsys->default_cssid : cssid;
1201 
1202     if (!channel_subsys->css[real_cssid]) {
1203         return NULL;
1204     }
1205 
1206     if (!channel_subsys->css[real_cssid]->sch_set[ssid]) {
1207         return NULL;
1208     }
1209 
1210     return channel_subsys->css[real_cssid]->sch_set[ssid]->sch[schid];
1211 }
1212 
1213 bool css_subch_visible(SubchDev *sch)
1214 {
1215     if (sch->ssid > channel_subsys->max_ssid) {
1216         return false;
1217     }
1218 
1219     if (sch->cssid != channel_subsys->default_cssid) {
1220         return (channel_subsys->max_cssid > 0);
1221     }
1222 
1223     return true;
1224 }
1225 
1226 bool css_present(uint8_t cssid)
1227 {
1228     return (channel_subsys->css[cssid] != NULL);
1229 }
1230 
1231 bool css_devno_used(uint8_t cssid, uint8_t ssid, uint16_t devno)
1232 {
1233     if (!channel_subsys->css[cssid]) {
1234         return false;
1235     }
1236     if (!channel_subsys->css[cssid]->sch_set[ssid]) {
1237         return false;
1238     }
1239 
1240     return !!test_bit(devno,
1241                       channel_subsys->css[cssid]->sch_set[ssid]->devnos_used);
1242 }
1243 
1244 void css_subch_assign(uint8_t cssid, uint8_t ssid, uint16_t schid,
1245                       uint16_t devno, SubchDev *sch)
1246 {
1247     CssImage *css;
1248     SubchSet *s_set;
1249 
1250     trace_css_assign_subch(sch ? "assign" : "deassign", cssid, ssid, schid,
1251                            devno);
1252     if (!channel_subsys->css[cssid]) {
1253         fprintf(stderr,
1254                 "Suspicious call to %s (%x.%x.%04x) for non-existing css!\n",
1255                 __func__, cssid, ssid, schid);
1256         return;
1257     }
1258     css = channel_subsys->css[cssid];
1259 
1260     if (!css->sch_set[ssid]) {
1261         css->sch_set[ssid] = g_malloc0(sizeof(SubchSet));
1262     }
1263     s_set = css->sch_set[ssid];
1264 
1265     s_set->sch[schid] = sch;
1266     if (sch) {
1267         set_bit(schid, s_set->schids_used);
1268         set_bit(devno, s_set->devnos_used);
1269     } else {
1270         clear_bit(schid, s_set->schids_used);
1271         clear_bit(devno, s_set->devnos_used);
1272     }
1273 }
1274 
1275 void css_queue_crw(uint8_t rsc, uint8_t erc, int chain, uint16_t rsid)
1276 {
1277     CrwContainer *crw_cont;
1278 
1279     trace_css_crw(rsc, erc, rsid, chain ? "(chained)" : "");
1280     /* TODO: Maybe use a static crw pool? */
1281     crw_cont = g_try_malloc0(sizeof(CrwContainer));
1282     if (!crw_cont) {
1283         channel_subsys->crws_lost = true;
1284         return;
1285     }
1286     crw_cont->crw.flags = (rsc << 8) | erc;
1287     if (chain) {
1288         crw_cont->crw.flags |= CRW_FLAGS_MASK_C;
1289     }
1290     crw_cont->crw.rsid = rsid;
1291     if (channel_subsys->crws_lost) {
1292         crw_cont->crw.flags |= CRW_FLAGS_MASK_R;
1293         channel_subsys->crws_lost = false;
1294     }
1295 
1296     QTAILQ_INSERT_TAIL(&channel_subsys->pending_crws, crw_cont, sibling);
1297 
1298     if (channel_subsys->do_crw_mchk) {
1299         channel_subsys->do_crw_mchk = false;
1300         /* Inject crw pending machine check. */
1301         s390_crw_mchk();
1302     }
1303 }
1304 
1305 void css_generate_sch_crws(uint8_t cssid, uint8_t ssid, uint16_t schid,
1306                            int hotplugged, int add)
1307 {
1308     uint8_t guest_cssid;
1309     bool chain_crw;
1310 
1311     if (add && !hotplugged) {
1312         return;
1313     }
1314     if (channel_subsys->max_cssid == 0) {
1315         /* Default cssid shows up as 0. */
1316         guest_cssid = (cssid == channel_subsys->default_cssid) ? 0 : cssid;
1317     } else {
1318         /* Show real cssid to the guest. */
1319         guest_cssid = cssid;
1320     }
1321     /*
1322      * Only notify for higher subchannel sets/channel subsystems if the
1323      * guest has enabled it.
1324      */
1325     if ((ssid > channel_subsys->max_ssid) ||
1326         (guest_cssid > channel_subsys->max_cssid) ||
1327         ((channel_subsys->max_cssid == 0) &&
1328          (cssid != channel_subsys->default_cssid))) {
1329         return;
1330     }
1331     chain_crw = (channel_subsys->max_ssid > 0) ||
1332             (channel_subsys->max_cssid > 0);
1333     css_queue_crw(CRW_RSC_SUBCH, CRW_ERC_IPI, chain_crw ? 1 : 0, schid);
1334     if (chain_crw) {
1335         css_queue_crw(CRW_RSC_SUBCH, CRW_ERC_IPI, 0,
1336                       (guest_cssid << 8) | (ssid << 4));
1337     }
1338 }
1339 
1340 void css_generate_chp_crws(uint8_t cssid, uint8_t chpid)
1341 {
1342     /* TODO */
1343 }
1344 
1345 void css_generate_css_crws(uint8_t cssid)
1346 {
1347     css_queue_crw(CRW_RSC_CSS, 0, 0, cssid);
1348 }
1349 
1350 int css_enable_mcsse(void)
1351 {
1352     trace_css_enable_facility("mcsse");
1353     channel_subsys->max_cssid = MAX_CSSID;
1354     return 0;
1355 }
1356 
1357 int css_enable_mss(void)
1358 {
1359     trace_css_enable_facility("mss");
1360     channel_subsys->max_ssid = MAX_SSID;
1361     return 0;
1362 }
1363 
1364 void subch_device_save(SubchDev *s, QEMUFile *f)
1365 {
1366     int i;
1367 
1368     qemu_put_byte(f, s->cssid);
1369     qemu_put_byte(f, s->ssid);
1370     qemu_put_be16(f, s->schid);
1371     qemu_put_be16(f, s->devno);
1372     qemu_put_byte(f, s->thinint_active);
1373     /* SCHIB */
1374     /*     PMCW */
1375     qemu_put_be32(f, s->curr_status.pmcw.intparm);
1376     qemu_put_be16(f, s->curr_status.pmcw.flags);
1377     qemu_put_be16(f, s->curr_status.pmcw.devno);
1378     qemu_put_byte(f, s->curr_status.pmcw.lpm);
1379     qemu_put_byte(f, s->curr_status.pmcw.pnom);
1380     qemu_put_byte(f, s->curr_status.pmcw.lpum);
1381     qemu_put_byte(f, s->curr_status.pmcw.pim);
1382     qemu_put_be16(f, s->curr_status.pmcw.mbi);
1383     qemu_put_byte(f, s->curr_status.pmcw.pom);
1384     qemu_put_byte(f, s->curr_status.pmcw.pam);
1385     qemu_put_buffer(f, s->curr_status.pmcw.chpid, 8);
1386     qemu_put_be32(f, s->curr_status.pmcw.chars);
1387     /*     SCSW */
1388     qemu_put_be16(f, s->curr_status.scsw.flags);
1389     qemu_put_be16(f, s->curr_status.scsw.ctrl);
1390     qemu_put_be32(f, s->curr_status.scsw.cpa);
1391     qemu_put_byte(f, s->curr_status.scsw.dstat);
1392     qemu_put_byte(f, s->curr_status.scsw.cstat);
1393     qemu_put_be16(f, s->curr_status.scsw.count);
1394     qemu_put_be64(f, s->curr_status.mba);
1395     qemu_put_buffer(f, s->curr_status.mda, 4);
1396     /* end SCHIB */
1397     qemu_put_buffer(f, s->sense_data, 32);
1398     qemu_put_be64(f, s->channel_prog);
1399     /* last cmd */
1400     qemu_put_byte(f, s->last_cmd.cmd_code);
1401     qemu_put_byte(f, s->last_cmd.flags);
1402     qemu_put_be16(f, s->last_cmd.count);
1403     qemu_put_be32(f, s->last_cmd.cda);
1404     qemu_put_byte(f, s->last_cmd_valid);
1405     qemu_put_byte(f, s->id.reserved);
1406     qemu_put_be16(f, s->id.cu_type);
1407     qemu_put_byte(f, s->id.cu_model);
1408     qemu_put_be16(f, s->id.dev_type);
1409     qemu_put_byte(f, s->id.dev_model);
1410     qemu_put_byte(f, s->id.unused);
1411     for (i = 0; i < ARRAY_SIZE(s->id.ciw); i++) {
1412         qemu_put_byte(f, s->id.ciw[i].type);
1413         qemu_put_byte(f, s->id.ciw[i].command);
1414         qemu_put_be16(f, s->id.ciw[i].count);
1415     }
1416     qemu_put_byte(f, s->ccw_fmt_1);
1417     qemu_put_byte(f, s->ccw_no_data_cnt);
1418     return;
1419 }
1420 
1421 int subch_device_load(SubchDev *s, QEMUFile *f)
1422 {
1423     int i;
1424 
1425     s->cssid = qemu_get_byte(f);
1426     s->ssid = qemu_get_byte(f);
1427     s->schid = qemu_get_be16(f);
1428     s->devno = qemu_get_be16(f);
1429     s->thinint_active = qemu_get_byte(f);
1430     /* SCHIB */
1431     /*     PMCW */
1432     s->curr_status.pmcw.intparm = qemu_get_be32(f);
1433     s->curr_status.pmcw.flags = qemu_get_be16(f);
1434     s->curr_status.pmcw.devno = qemu_get_be16(f);
1435     s->curr_status.pmcw.lpm = qemu_get_byte(f);
1436     s->curr_status.pmcw.pnom  = qemu_get_byte(f);
1437     s->curr_status.pmcw.lpum = qemu_get_byte(f);
1438     s->curr_status.pmcw.pim = qemu_get_byte(f);
1439     s->curr_status.pmcw.mbi = qemu_get_be16(f);
1440     s->curr_status.pmcw.pom = qemu_get_byte(f);
1441     s->curr_status.pmcw.pam = qemu_get_byte(f);
1442     qemu_get_buffer(f, s->curr_status.pmcw.chpid, 8);
1443     s->curr_status.pmcw.chars = qemu_get_be32(f);
1444     /*     SCSW */
1445     s->curr_status.scsw.flags = qemu_get_be16(f);
1446     s->curr_status.scsw.ctrl = qemu_get_be16(f);
1447     s->curr_status.scsw.cpa = qemu_get_be32(f);
1448     s->curr_status.scsw.dstat = qemu_get_byte(f);
1449     s->curr_status.scsw.cstat = qemu_get_byte(f);
1450     s->curr_status.scsw.count = qemu_get_be16(f);
1451     s->curr_status.mba = qemu_get_be64(f);
1452     qemu_get_buffer(f, s->curr_status.mda, 4);
1453     /* end SCHIB */
1454     qemu_get_buffer(f, s->sense_data, 32);
1455     s->channel_prog = qemu_get_be64(f);
1456     /* last cmd */
1457     s->last_cmd.cmd_code = qemu_get_byte(f);
1458     s->last_cmd.flags = qemu_get_byte(f);
1459     s->last_cmd.count = qemu_get_be16(f);
1460     s->last_cmd.cda = qemu_get_be32(f);
1461     s->last_cmd_valid = qemu_get_byte(f);
1462     s->id.reserved = qemu_get_byte(f);
1463     s->id.cu_type = qemu_get_be16(f);
1464     s->id.cu_model = qemu_get_byte(f);
1465     s->id.dev_type = qemu_get_be16(f);
1466     s->id.dev_model = qemu_get_byte(f);
1467     s->id.unused = qemu_get_byte(f);
1468     for (i = 0; i < ARRAY_SIZE(s->id.ciw); i++) {
1469         s->id.ciw[i].type = qemu_get_byte(f);
1470         s->id.ciw[i].command = qemu_get_byte(f);
1471         s->id.ciw[i].count = qemu_get_be16(f);
1472     }
1473     s->ccw_fmt_1 = qemu_get_byte(f);
1474     s->ccw_no_data_cnt = qemu_get_byte(f);
1475     /*
1476      * Hack alert. We don't migrate the channel subsystem status (no
1477      * device!), but we need to find out if the guest enabled mss/mcss-e.
1478      * If the subchannel is enabled, it certainly was able to access it,
1479      * so adjust the max_ssid/max_cssid values for relevant ssid/cssid
1480      * values. This is not watertight, but better than nothing.
1481      */
1482     if (s->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ENA) {
1483         if (s->ssid) {
1484             channel_subsys->max_ssid = MAX_SSID;
1485         }
1486         if (s->cssid != channel_subsys->default_cssid) {
1487             channel_subsys->max_cssid = MAX_CSSID;
1488         }
1489     }
1490     return 0;
1491 }
1492 
1493 
1494 static void css_init(void)
1495 {
1496     channel_subsys = g_malloc0(sizeof(*channel_subsys));
1497     QTAILQ_INIT(&channel_subsys->pending_crws);
1498     channel_subsys->do_crw_mchk = true;
1499     channel_subsys->crws_lost = false;
1500     channel_subsys->chnmon_active = false;
1501     QTAILQ_INIT(&channel_subsys->io_adapters);
1502 }
1503 machine_init(css_init);
1504 
1505 void css_reset_sch(SubchDev *sch)
1506 {
1507     PMCW *p = &sch->curr_status.pmcw;
1508 
1509     if ((p->flags & PMCW_FLAGS_MASK_ENA) != 0 && sch->disable_cb) {
1510         sch->disable_cb(sch);
1511     }
1512 
1513     p->intparm = 0;
1514     p->flags &= ~(PMCW_FLAGS_MASK_ISC | PMCW_FLAGS_MASK_ENA |
1515                   PMCW_FLAGS_MASK_LM | PMCW_FLAGS_MASK_MME |
1516                   PMCW_FLAGS_MASK_MP | PMCW_FLAGS_MASK_TF);
1517     p->flags |= PMCW_FLAGS_MASK_DNV;
1518     p->devno = sch->devno;
1519     p->pim = 0x80;
1520     p->lpm = p->pim;
1521     p->pnom = 0;
1522     p->lpum = 0;
1523     p->mbi = 0;
1524     p->pom = 0xff;
1525     p->pam = 0x80;
1526     p->chars &= ~(PMCW_CHARS_MASK_MBFC | PMCW_CHARS_MASK_XMWME |
1527                   PMCW_CHARS_MASK_CSENSE);
1528 
1529     memset(&sch->curr_status.scsw, 0, sizeof(sch->curr_status.scsw));
1530     sch->curr_status.mba = 0;
1531 
1532     sch->channel_prog = 0x0;
1533     sch->last_cmd_valid = false;
1534     sch->thinint_active = false;
1535 }
1536 
1537 void css_reset(void)
1538 {
1539     CrwContainer *crw_cont;
1540 
1541     /* Clean up monitoring. */
1542     channel_subsys->chnmon_active = false;
1543     channel_subsys->chnmon_area = 0;
1544 
1545     /* Clear pending CRWs. */
1546     while ((crw_cont = QTAILQ_FIRST(&channel_subsys->pending_crws))) {
1547         QTAILQ_REMOVE(&channel_subsys->pending_crws, crw_cont, sibling);
1548         g_free(crw_cont);
1549     }
1550     channel_subsys->do_crw_mchk = true;
1551     channel_subsys->crws_lost = false;
1552 
1553     /* Reset maximum ids. */
1554     channel_subsys->max_cssid = 0;
1555     channel_subsys->max_ssid = 0;
1556 }
1557