xref: /openbmc/qemu/hw/s390x/css.c (revision 795c40b8)
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 "qemu/osdep.h"
13 #include "qapi/error.h"
14 #include "qapi/visitor.h"
15 #include "hw/qdev.h"
16 #include "qemu/bitops.h"
17 #include "exec/address-spaces.h"
18 #include "cpu.h"
19 #include "hw/s390x/ioinst.h"
20 #include "hw/s390x/css.h"
21 #include "trace.h"
22 #include "hw/s390x/s390_flic.h"
23 
24 typedef struct CrwContainer {
25     CRW crw;
26     QTAILQ_ENTRY(CrwContainer) sibling;
27 } CrwContainer;
28 
29 typedef struct ChpInfo {
30     uint8_t in_use;
31     uint8_t type;
32     uint8_t is_virtual;
33 } ChpInfo;
34 
35 typedef struct SubchSet {
36     SubchDev *sch[MAX_SCHID + 1];
37     unsigned long schids_used[BITS_TO_LONGS(MAX_SCHID + 1)];
38     unsigned long devnos_used[BITS_TO_LONGS(MAX_SCHID + 1)];
39 } SubchSet;
40 
41 typedef struct CssImage {
42     SubchSet *sch_set[MAX_SSID + 1];
43     ChpInfo chpids[MAX_CHPID + 1];
44 } CssImage;
45 
46 typedef struct IoAdapter {
47     uint32_t id;
48     uint8_t type;
49     uint8_t isc;
50 } IoAdapter;
51 
52 typedef struct ChannelSubSys {
53     QTAILQ_HEAD(, CrwContainer) pending_crws;
54     bool sei_pending;
55     bool do_crw_mchk;
56     bool crws_lost;
57     uint8_t max_cssid;
58     uint8_t max_ssid;
59     bool chnmon_active;
60     uint64_t chnmon_area;
61     CssImage *css[MAX_CSSID + 1];
62     uint8_t default_cssid;
63     IoAdapter *io_adapters[CSS_IO_ADAPTER_TYPE_NUMS][MAX_ISC + 1];
64     QTAILQ_HEAD(, IndAddr) indicator_addresses;
65 } ChannelSubSys;
66 
67 static ChannelSubSys channel_subsys = {
68     .pending_crws = QTAILQ_HEAD_INITIALIZER(channel_subsys.pending_crws),
69     .do_crw_mchk = true,
70     .sei_pending = false,
71     .do_crw_mchk = true,
72     .crws_lost = false,
73     .chnmon_active = false,
74     .indicator_addresses =
75         QTAILQ_HEAD_INITIALIZER(channel_subsys.indicator_addresses),
76 };
77 
78 IndAddr *get_indicator(hwaddr ind_addr, int len)
79 {
80     IndAddr *indicator;
81 
82     QTAILQ_FOREACH(indicator, &channel_subsys.indicator_addresses, sibling) {
83         if (indicator->addr == ind_addr) {
84             indicator->refcnt++;
85             return indicator;
86         }
87     }
88     indicator = g_new0(IndAddr, 1);
89     indicator->addr = ind_addr;
90     indicator->len = len;
91     indicator->refcnt = 1;
92     QTAILQ_INSERT_TAIL(&channel_subsys.indicator_addresses,
93                        indicator, sibling);
94     return indicator;
95 }
96 
97 static int s390_io_adapter_map(AdapterInfo *adapter, uint64_t map_addr,
98                                bool do_map)
99 {
100     S390FLICState *fs = s390_get_flic();
101     S390FLICStateClass *fsc = S390_FLIC_COMMON_GET_CLASS(fs);
102 
103     return fsc->io_adapter_map(fs, adapter->adapter_id, map_addr, do_map);
104 }
105 
106 void release_indicator(AdapterInfo *adapter, IndAddr *indicator)
107 {
108     assert(indicator->refcnt > 0);
109     indicator->refcnt--;
110     if (indicator->refcnt > 0) {
111         return;
112     }
113     QTAILQ_REMOVE(&channel_subsys.indicator_addresses, indicator, sibling);
114     if (indicator->map) {
115         s390_io_adapter_map(adapter, indicator->map, false);
116     }
117     g_free(indicator);
118 }
119 
120 int map_indicator(AdapterInfo *adapter, IndAddr *indicator)
121 {
122     int ret;
123 
124     if (indicator->map) {
125         return 0; /* already mapped is not an error */
126     }
127     indicator->map = indicator->addr;
128     ret = s390_io_adapter_map(adapter, indicator->map, true);
129     if ((ret != 0) && (ret != -ENOSYS)) {
130         goto out_err;
131     }
132     return 0;
133 
134 out_err:
135     indicator->map = 0;
136     return ret;
137 }
138 
139 int css_create_css_image(uint8_t cssid, bool default_image)
140 {
141     trace_css_new_image(cssid, default_image ? "(default)" : "");
142     /* 255 is reserved */
143     if (cssid == 255) {
144         return -EINVAL;
145     }
146     if (channel_subsys.css[cssid]) {
147         return -EBUSY;
148     }
149     channel_subsys.css[cssid] = g_malloc0(sizeof(CssImage));
150     if (default_image) {
151         channel_subsys.default_cssid = cssid;
152     }
153     return 0;
154 }
155 
156 uint32_t css_get_adapter_id(CssIoAdapterType type, uint8_t isc)
157 {
158     if (type >= CSS_IO_ADAPTER_TYPE_NUMS || isc > MAX_ISC ||
159         !channel_subsys.io_adapters[type][isc]) {
160         return -1;
161     }
162 
163     return channel_subsys.io_adapters[type][isc]->id;
164 }
165 
166 /**
167  * css_register_io_adapters: Register I/O adapters per ISC during init
168  *
169  * @swap: an indication if byte swap is needed.
170  * @maskable: an indication if the adapter is subject to the mask operation.
171  * @errp: location to store error information.
172  */
173 void css_register_io_adapters(CssIoAdapterType type, bool swap, bool maskable,
174                               Error **errp)
175 {
176     uint32_t id;
177     int ret, isc;
178     IoAdapter *adapter;
179     S390FLICState *fs = s390_get_flic();
180     S390FLICStateClass *fsc = S390_FLIC_COMMON_GET_CLASS(fs);
181 
182     /*
183      * Disallow multiple registrations for the same device type.
184      * Report an error if registering for an already registered type.
185      */
186     if (channel_subsys.io_adapters[type][0]) {
187         error_setg(errp, "Adapters for type %d already registered", type);
188     }
189 
190     for (isc = 0; isc <= MAX_ISC; isc++) {
191         id = (type << 3) | isc;
192         ret = fsc->register_io_adapter(fs, id, isc, swap, maskable);
193         if (ret == 0) {
194             adapter = g_new0(IoAdapter, 1);
195             adapter->id = id;
196             adapter->isc = isc;
197             adapter->type = type;
198             channel_subsys.io_adapters[type][isc] = adapter;
199         } else {
200             error_setg_errno(errp, -ret, "Unexpected error %d when "
201                              "registering adapter %d", ret, id);
202             break;
203         }
204     }
205 
206     /*
207      * No need to free registered adapters in kvm: kvm will clean up
208      * when the machine goes away.
209      */
210     if (ret) {
211         for (isc--; isc >= 0; isc--) {
212             g_free(channel_subsys.io_adapters[type][isc]);
213             channel_subsys.io_adapters[type][isc] = NULL;
214         }
215     }
216 
217 }
218 
219 static void css_clear_io_interrupt(uint16_t subchannel_id,
220                                    uint16_t subchannel_nr)
221 {
222     Error *err = NULL;
223     static bool no_clear_irq;
224     S390FLICState *fs = s390_get_flic();
225     S390FLICStateClass *fsc = S390_FLIC_COMMON_GET_CLASS(fs);
226     int r;
227 
228     if (unlikely(no_clear_irq)) {
229         return;
230     }
231     r = fsc->clear_io_irq(fs, subchannel_id, subchannel_nr);
232     switch (r) {
233     case 0:
234         break;
235     case -ENOSYS:
236         no_clear_irq = true;
237         /*
238         * Ignore unavailability, as the user can't do anything
239         * about it anyway.
240         */
241         break;
242     default:
243         error_setg_errno(&err, -r, "unexpected error condition");
244         error_propagate(&error_abort, err);
245     }
246 }
247 
248 static inline uint16_t css_do_build_subchannel_id(uint8_t cssid, uint8_t ssid)
249 {
250     if (channel_subsys.max_cssid > 0) {
251         return (cssid << 8) | (1 << 3) | (ssid << 1) | 1;
252     }
253     return (ssid << 1) | 1;
254 }
255 
256 uint16_t css_build_subchannel_id(SubchDev *sch)
257 {
258     return css_do_build_subchannel_id(sch->cssid, sch->ssid);
259 }
260 
261 static void css_inject_io_interrupt(SubchDev *sch)
262 {
263     uint8_t isc = (sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ISC) >> 11;
264 
265     trace_css_io_interrupt(sch->cssid, sch->ssid, sch->schid,
266                            sch->curr_status.pmcw.intparm, isc, "");
267     s390_io_interrupt(css_build_subchannel_id(sch),
268                       sch->schid,
269                       sch->curr_status.pmcw.intparm,
270                       isc << 27);
271 }
272 
273 void css_conditional_io_interrupt(SubchDev *sch)
274 {
275     /*
276      * If the subchannel is not currently status pending, make it pending
277      * with alert status.
278      */
279     if (!(sch->curr_status.scsw.ctrl & SCSW_STCTL_STATUS_PEND)) {
280         uint8_t isc = (sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ISC) >> 11;
281 
282         trace_css_io_interrupt(sch->cssid, sch->ssid, sch->schid,
283                                sch->curr_status.pmcw.intparm, isc,
284                                "(unsolicited)");
285         sch->curr_status.scsw.ctrl &= ~SCSW_CTRL_MASK_STCTL;
286         sch->curr_status.scsw.ctrl |=
287             SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
288         /* Inject an I/O interrupt. */
289         s390_io_interrupt(css_build_subchannel_id(sch),
290                           sch->schid,
291                           sch->curr_status.pmcw.intparm,
292                           isc << 27);
293     }
294 }
295 
296 void css_adapter_interrupt(uint8_t isc)
297 {
298     uint32_t io_int_word = (isc << 27) | IO_INT_WORD_AI;
299 
300     trace_css_adapter_interrupt(isc);
301     s390_io_interrupt(0, 0, 0, io_int_word);
302 }
303 
304 static void sch_handle_clear_func(SubchDev *sch)
305 {
306     PMCW *p = &sch->curr_status.pmcw;
307     SCSW *s = &sch->curr_status.scsw;
308     int path;
309 
310     /* Path management: In our simple css, we always choose the only path. */
311     path = 0x80;
312 
313     /* Reset values prior to 'issuing the clear signal'. */
314     p->lpum = 0;
315     p->pom = 0xff;
316     s->flags &= ~SCSW_FLAGS_MASK_PNO;
317 
318     /* We always 'attempt to issue the clear signal', and we always succeed. */
319     sch->channel_prog = 0x0;
320     sch->last_cmd_valid = false;
321     s->ctrl &= ~SCSW_ACTL_CLEAR_PEND;
322     s->ctrl |= SCSW_STCTL_STATUS_PEND;
323 
324     s->dstat = 0;
325     s->cstat = 0;
326     p->lpum = path;
327 
328 }
329 
330 static void sch_handle_halt_func(SubchDev *sch)
331 {
332 
333     PMCW *p = &sch->curr_status.pmcw;
334     SCSW *s = &sch->curr_status.scsw;
335     hwaddr curr_ccw = sch->channel_prog;
336     int path;
337 
338     /* Path management: In our simple css, we always choose the only path. */
339     path = 0x80;
340 
341     /* We always 'attempt to issue the halt signal', and we always succeed. */
342     sch->channel_prog = 0x0;
343     sch->last_cmd_valid = false;
344     s->ctrl &= ~SCSW_ACTL_HALT_PEND;
345     s->ctrl |= SCSW_STCTL_STATUS_PEND;
346 
347     if ((s->ctrl & (SCSW_ACTL_SUBCH_ACTIVE | SCSW_ACTL_DEVICE_ACTIVE)) ||
348         !((s->ctrl & SCSW_ACTL_START_PEND) ||
349           (s->ctrl & SCSW_ACTL_SUSP))) {
350         s->dstat = SCSW_DSTAT_DEVICE_END;
351     }
352     if ((s->ctrl & (SCSW_ACTL_SUBCH_ACTIVE | SCSW_ACTL_DEVICE_ACTIVE)) ||
353         (s->ctrl & SCSW_ACTL_SUSP)) {
354         s->cpa = curr_ccw + 8;
355     }
356     s->cstat = 0;
357     p->lpum = path;
358 
359 }
360 
361 static void copy_sense_id_to_guest(SenseId *dest, SenseId *src)
362 {
363     int i;
364 
365     dest->reserved = src->reserved;
366     dest->cu_type = cpu_to_be16(src->cu_type);
367     dest->cu_model = src->cu_model;
368     dest->dev_type = cpu_to_be16(src->dev_type);
369     dest->dev_model = src->dev_model;
370     dest->unused = src->unused;
371     for (i = 0; i < ARRAY_SIZE(dest->ciw); i++) {
372         dest->ciw[i].type = src->ciw[i].type;
373         dest->ciw[i].command = src->ciw[i].command;
374         dest->ciw[i].count = cpu_to_be16(src->ciw[i].count);
375     }
376 }
377 
378 static CCW1 copy_ccw_from_guest(hwaddr addr, bool fmt1)
379 {
380     CCW0 tmp0;
381     CCW1 tmp1;
382     CCW1 ret;
383 
384     if (fmt1) {
385         cpu_physical_memory_read(addr, &tmp1, sizeof(tmp1));
386         ret.cmd_code = tmp1.cmd_code;
387         ret.flags = tmp1.flags;
388         ret.count = be16_to_cpu(tmp1.count);
389         ret.cda = be32_to_cpu(tmp1.cda);
390     } else {
391         cpu_physical_memory_read(addr, &tmp0, sizeof(tmp0));
392         if ((tmp0.cmd_code & 0x0f) == CCW_CMD_TIC) {
393             ret.cmd_code = CCW_CMD_TIC;
394             ret.flags = 0;
395             ret.count = 0;
396         } else {
397             ret.cmd_code = tmp0.cmd_code;
398             ret.flags = tmp0.flags;
399             ret.count = be16_to_cpu(tmp0.count);
400         }
401         ret.cda = be16_to_cpu(tmp0.cda1) | (tmp0.cda0 << 16);
402     }
403     return ret;
404 }
405 
406 static int css_interpret_ccw(SubchDev *sch, hwaddr ccw_addr,
407                              bool suspend_allowed)
408 {
409     int ret;
410     bool check_len;
411     int len;
412     CCW1 ccw;
413 
414     if (!ccw_addr) {
415         return -EIO;
416     }
417 
418     /* Translate everything to format-1 ccws - the information is the same. */
419     ccw = copy_ccw_from_guest(ccw_addr, sch->ccw_fmt_1);
420 
421     /* Check for invalid command codes. */
422     if ((ccw.cmd_code & 0x0f) == 0) {
423         return -EINVAL;
424     }
425     if (((ccw.cmd_code & 0x0f) == CCW_CMD_TIC) &&
426         ((ccw.cmd_code & 0xf0) != 0)) {
427         return -EINVAL;
428     }
429     if (!sch->ccw_fmt_1 && (ccw.count == 0) &&
430         (ccw.cmd_code != CCW_CMD_TIC)) {
431         return -EINVAL;
432     }
433 
434     if (ccw.flags & CCW_FLAG_SUSPEND) {
435         return suspend_allowed ? -EINPROGRESS : -EINVAL;
436     }
437 
438     check_len = !((ccw.flags & CCW_FLAG_SLI) && !(ccw.flags & CCW_FLAG_DC));
439 
440     if (!ccw.cda) {
441         if (sch->ccw_no_data_cnt == 255) {
442             return -EINVAL;
443         }
444         sch->ccw_no_data_cnt++;
445     }
446 
447     /* Look at the command. */
448     switch (ccw.cmd_code) {
449     case CCW_CMD_NOOP:
450         /* Nothing to do. */
451         ret = 0;
452         break;
453     case CCW_CMD_BASIC_SENSE:
454         if (check_len) {
455             if (ccw.count != sizeof(sch->sense_data)) {
456                 ret = -EINVAL;
457                 break;
458             }
459         }
460         len = MIN(ccw.count, sizeof(sch->sense_data));
461         cpu_physical_memory_write(ccw.cda, sch->sense_data, len);
462         sch->curr_status.scsw.count = ccw.count - len;
463         memset(sch->sense_data, 0, sizeof(sch->sense_data));
464         ret = 0;
465         break;
466     case CCW_CMD_SENSE_ID:
467     {
468         SenseId sense_id;
469 
470         copy_sense_id_to_guest(&sense_id, &sch->id);
471         /* Sense ID information is device specific. */
472         if (check_len) {
473             if (ccw.count != sizeof(sense_id)) {
474                 ret = -EINVAL;
475                 break;
476             }
477         }
478         len = MIN(ccw.count, sizeof(sense_id));
479         /*
480          * Only indicate 0xff in the first sense byte if we actually
481          * have enough place to store at least bytes 0-3.
482          */
483         if (len >= 4) {
484             sense_id.reserved = 0xff;
485         } else {
486             sense_id.reserved = 0;
487         }
488         cpu_physical_memory_write(ccw.cda, &sense_id, len);
489         sch->curr_status.scsw.count = ccw.count - len;
490         ret = 0;
491         break;
492     }
493     case CCW_CMD_TIC:
494         if (sch->last_cmd_valid && (sch->last_cmd.cmd_code == CCW_CMD_TIC)) {
495             ret = -EINVAL;
496             break;
497         }
498         if (ccw.flags & (CCW_FLAG_CC | CCW_FLAG_DC)) {
499             ret = -EINVAL;
500             break;
501         }
502         sch->channel_prog = ccw.cda;
503         ret = -EAGAIN;
504         break;
505     default:
506         if (sch->ccw_cb) {
507             /* Handle device specific commands. */
508             ret = sch->ccw_cb(sch, ccw);
509         } else {
510             ret = -ENOSYS;
511         }
512         break;
513     }
514     sch->last_cmd = ccw;
515     sch->last_cmd_valid = true;
516     if (ret == 0) {
517         if (ccw.flags & CCW_FLAG_CC) {
518             sch->channel_prog += 8;
519             ret = -EAGAIN;
520         }
521     }
522 
523     return ret;
524 }
525 
526 static void sch_handle_start_func(SubchDev *sch, ORB *orb)
527 {
528 
529     PMCW *p = &sch->curr_status.pmcw;
530     SCSW *s = &sch->curr_status.scsw;
531     int path;
532     int ret;
533     bool suspend_allowed;
534 
535     /* Path management: In our simple css, we always choose the only path. */
536     path = 0x80;
537 
538     if (!(s->ctrl & SCSW_ACTL_SUSP)) {
539         /* Start Function triggered via ssch, i.e. we have an ORB */
540         s->cstat = 0;
541         s->dstat = 0;
542         /* Look at the orb and try to execute the channel program. */
543         assert(orb != NULL); /* resume does not pass an orb */
544         p->intparm = orb->intparm;
545         if (!(orb->lpm & path)) {
546             /* Generate a deferred cc 3 condition. */
547             s->flags |= SCSW_FLAGS_MASK_CC;
548             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
549             s->ctrl |= (SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND);
550             return;
551         }
552         sch->ccw_fmt_1 = !!(orb->ctrl0 & ORB_CTRL0_MASK_FMT);
553         s->flags |= (sch->ccw_fmt_1) ? SCSW_FLAGS_MASK_FMT : 0;
554         sch->ccw_no_data_cnt = 0;
555         suspend_allowed = !!(orb->ctrl0 & ORB_CTRL0_MASK_SPND);
556     } else {
557         /* Start Function resumed via rsch, i.e. we don't have an
558          * ORB */
559         s->ctrl &= ~(SCSW_ACTL_SUSP | SCSW_ACTL_RESUME_PEND);
560         /* The channel program had been suspended before. */
561         suspend_allowed = true;
562     }
563     sch->last_cmd_valid = false;
564     do {
565         ret = css_interpret_ccw(sch, sch->channel_prog, suspend_allowed);
566         switch (ret) {
567         case -EAGAIN:
568             /* ccw chain, continue processing */
569             break;
570         case 0:
571             /* success */
572             s->ctrl &= ~SCSW_ACTL_START_PEND;
573             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
574             s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
575                     SCSW_STCTL_STATUS_PEND;
576             s->dstat = SCSW_DSTAT_CHANNEL_END | SCSW_DSTAT_DEVICE_END;
577             s->cpa = sch->channel_prog + 8;
578             break;
579         case -EIO:
580             /* I/O errors, status depends on specific devices */
581             break;
582         case -ENOSYS:
583             /* unsupported command, generate unit check (command reject) */
584             s->ctrl &= ~SCSW_ACTL_START_PEND;
585             s->dstat = SCSW_DSTAT_UNIT_CHECK;
586             /* Set sense bit 0 in ecw0. */
587             sch->sense_data[0] = 0x80;
588             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
589             s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
590                     SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
591             s->cpa = sch->channel_prog + 8;
592             break;
593         case -EFAULT:
594             /* memory problem, generate channel data check */
595             s->ctrl &= ~SCSW_ACTL_START_PEND;
596             s->cstat = SCSW_CSTAT_DATA_CHECK;
597             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
598             s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
599                     SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
600             s->cpa = sch->channel_prog + 8;
601             break;
602         case -EBUSY:
603             /* subchannel busy, generate deferred cc 1 */
604             s->flags &= ~SCSW_FLAGS_MASK_CC;
605             s->flags |= (1 << 8);
606             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
607             s->ctrl |= SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
608             break;
609         case -EINPROGRESS:
610             /* channel program has been suspended */
611             s->ctrl &= ~SCSW_ACTL_START_PEND;
612             s->ctrl |= SCSW_ACTL_SUSP;
613             break;
614         default:
615             /* error, generate channel program check */
616             s->ctrl &= ~SCSW_ACTL_START_PEND;
617             s->cstat = SCSW_CSTAT_PROG_CHECK;
618             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
619             s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
620                     SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
621             s->cpa = sch->channel_prog + 8;
622             break;
623         }
624     } while (ret == -EAGAIN);
625 
626 }
627 
628 /*
629  * On real machines, this would run asynchronously to the main vcpus.
630  * We might want to make some parts of the ssch handling (interpreting
631  * read/writes) asynchronous later on if we start supporting more than
632  * our current very simple devices.
633  */
634 static void do_subchannel_work(SubchDev *sch, ORB *orb)
635 {
636 
637     SCSW *s = &sch->curr_status.scsw;
638 
639     if (s->ctrl & SCSW_FCTL_CLEAR_FUNC) {
640         sch_handle_clear_func(sch);
641     } else if (s->ctrl & SCSW_FCTL_HALT_FUNC) {
642         sch_handle_halt_func(sch);
643     } else if (s->ctrl & SCSW_FCTL_START_FUNC) {
644         /* Triggered by both ssch and rsch. */
645         sch_handle_start_func(sch, orb);
646     } else {
647         /* Cannot happen. */
648         return;
649     }
650     css_inject_io_interrupt(sch);
651 }
652 
653 static void copy_pmcw_to_guest(PMCW *dest, const PMCW *src)
654 {
655     int i;
656 
657     dest->intparm = cpu_to_be32(src->intparm);
658     dest->flags = cpu_to_be16(src->flags);
659     dest->devno = cpu_to_be16(src->devno);
660     dest->lpm = src->lpm;
661     dest->pnom = src->pnom;
662     dest->lpum = src->lpum;
663     dest->pim = src->pim;
664     dest->mbi = cpu_to_be16(src->mbi);
665     dest->pom = src->pom;
666     dest->pam = src->pam;
667     for (i = 0; i < ARRAY_SIZE(dest->chpid); i++) {
668         dest->chpid[i] = src->chpid[i];
669     }
670     dest->chars = cpu_to_be32(src->chars);
671 }
672 
673 static void copy_scsw_to_guest(SCSW *dest, const SCSW *src)
674 {
675     dest->flags = cpu_to_be16(src->flags);
676     dest->ctrl = cpu_to_be16(src->ctrl);
677     dest->cpa = cpu_to_be32(src->cpa);
678     dest->dstat = src->dstat;
679     dest->cstat = src->cstat;
680     dest->count = cpu_to_be16(src->count);
681 }
682 
683 static void copy_schib_to_guest(SCHIB *dest, const SCHIB *src)
684 {
685     int i;
686 
687     copy_pmcw_to_guest(&dest->pmcw, &src->pmcw);
688     copy_scsw_to_guest(&dest->scsw, &src->scsw);
689     dest->mba = cpu_to_be64(src->mba);
690     for (i = 0; i < ARRAY_SIZE(dest->mda); i++) {
691         dest->mda[i] = src->mda[i];
692     }
693 }
694 
695 int css_do_stsch(SubchDev *sch, SCHIB *schib)
696 {
697     /* Use current status. */
698     copy_schib_to_guest(schib, &sch->curr_status);
699     return 0;
700 }
701 
702 static void copy_pmcw_from_guest(PMCW *dest, const PMCW *src)
703 {
704     int i;
705 
706     dest->intparm = be32_to_cpu(src->intparm);
707     dest->flags = be16_to_cpu(src->flags);
708     dest->devno = be16_to_cpu(src->devno);
709     dest->lpm = src->lpm;
710     dest->pnom = src->pnom;
711     dest->lpum = src->lpum;
712     dest->pim = src->pim;
713     dest->mbi = be16_to_cpu(src->mbi);
714     dest->pom = src->pom;
715     dest->pam = src->pam;
716     for (i = 0; i < ARRAY_SIZE(dest->chpid); i++) {
717         dest->chpid[i] = src->chpid[i];
718     }
719     dest->chars = be32_to_cpu(src->chars);
720 }
721 
722 static void copy_scsw_from_guest(SCSW *dest, const SCSW *src)
723 {
724     dest->flags = be16_to_cpu(src->flags);
725     dest->ctrl = be16_to_cpu(src->ctrl);
726     dest->cpa = be32_to_cpu(src->cpa);
727     dest->dstat = src->dstat;
728     dest->cstat = src->cstat;
729     dest->count = be16_to_cpu(src->count);
730 }
731 
732 static void copy_schib_from_guest(SCHIB *dest, const SCHIB *src)
733 {
734     int i;
735 
736     copy_pmcw_from_guest(&dest->pmcw, &src->pmcw);
737     copy_scsw_from_guest(&dest->scsw, &src->scsw);
738     dest->mba = be64_to_cpu(src->mba);
739     for (i = 0; i < ARRAY_SIZE(dest->mda); i++) {
740         dest->mda[i] = src->mda[i];
741     }
742 }
743 
744 int css_do_msch(SubchDev *sch, const SCHIB *orig_schib)
745 {
746     SCSW *s = &sch->curr_status.scsw;
747     PMCW *p = &sch->curr_status.pmcw;
748     uint16_t oldflags;
749     int ret;
750     SCHIB schib;
751 
752     if (!(sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_DNV)) {
753         ret = 0;
754         goto out;
755     }
756 
757     if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
758         ret = -EINPROGRESS;
759         goto out;
760     }
761 
762     if (s->ctrl &
763         (SCSW_FCTL_START_FUNC|SCSW_FCTL_HALT_FUNC|SCSW_FCTL_CLEAR_FUNC)) {
764         ret = -EBUSY;
765         goto out;
766     }
767 
768     copy_schib_from_guest(&schib, orig_schib);
769     /* Only update the program-modifiable fields. */
770     p->intparm = schib.pmcw.intparm;
771     oldflags = p->flags;
772     p->flags &= ~(PMCW_FLAGS_MASK_ISC | PMCW_FLAGS_MASK_ENA |
773                   PMCW_FLAGS_MASK_LM | PMCW_FLAGS_MASK_MME |
774                   PMCW_FLAGS_MASK_MP);
775     p->flags |= schib.pmcw.flags &
776             (PMCW_FLAGS_MASK_ISC | PMCW_FLAGS_MASK_ENA |
777              PMCW_FLAGS_MASK_LM | PMCW_FLAGS_MASK_MME |
778              PMCW_FLAGS_MASK_MP);
779     p->lpm = schib.pmcw.lpm;
780     p->mbi = schib.pmcw.mbi;
781     p->pom = schib.pmcw.pom;
782     p->chars &= ~(PMCW_CHARS_MASK_MBFC | PMCW_CHARS_MASK_CSENSE);
783     p->chars |= schib.pmcw.chars &
784             (PMCW_CHARS_MASK_MBFC | PMCW_CHARS_MASK_CSENSE);
785     sch->curr_status.mba = schib.mba;
786 
787     /* Has the channel been disabled? */
788     if (sch->disable_cb && (oldflags & PMCW_FLAGS_MASK_ENA) != 0
789         && (p->flags & PMCW_FLAGS_MASK_ENA) == 0) {
790         sch->disable_cb(sch);
791     }
792 
793     ret = 0;
794 
795 out:
796     return ret;
797 }
798 
799 int css_do_xsch(SubchDev *sch)
800 {
801     SCSW *s = &sch->curr_status.scsw;
802     PMCW *p = &sch->curr_status.pmcw;
803     int ret;
804 
805     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
806         ret = -ENODEV;
807         goto out;
808     }
809 
810     if (!(s->ctrl & SCSW_CTRL_MASK_FCTL) ||
811         ((s->ctrl & SCSW_CTRL_MASK_FCTL) != SCSW_FCTL_START_FUNC) ||
812         (!(s->ctrl &
813            (SCSW_ACTL_RESUME_PEND | SCSW_ACTL_START_PEND | SCSW_ACTL_SUSP))) ||
814         (s->ctrl & SCSW_ACTL_SUBCH_ACTIVE)) {
815         ret = -EINPROGRESS;
816         goto out;
817     }
818 
819     if (s->ctrl & SCSW_CTRL_MASK_STCTL) {
820         ret = -EBUSY;
821         goto out;
822     }
823 
824     /* Cancel the current operation. */
825     s->ctrl &= ~(SCSW_FCTL_START_FUNC |
826                  SCSW_ACTL_RESUME_PEND |
827                  SCSW_ACTL_START_PEND |
828                  SCSW_ACTL_SUSP);
829     sch->channel_prog = 0x0;
830     sch->last_cmd_valid = false;
831     s->dstat = 0;
832     s->cstat = 0;
833     ret = 0;
834 
835 out:
836     return ret;
837 }
838 
839 int css_do_csch(SubchDev *sch)
840 {
841     SCSW *s = &sch->curr_status.scsw;
842     PMCW *p = &sch->curr_status.pmcw;
843     int ret;
844 
845     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
846         ret = -ENODEV;
847         goto out;
848     }
849 
850     /* Trigger the clear function. */
851     s->ctrl &= ~(SCSW_CTRL_MASK_FCTL | SCSW_CTRL_MASK_ACTL);
852     s->ctrl |= SCSW_FCTL_CLEAR_FUNC | SCSW_ACTL_CLEAR_PEND;
853 
854     do_subchannel_work(sch, NULL);
855     ret = 0;
856 
857 out:
858     return ret;
859 }
860 
861 int css_do_hsch(SubchDev *sch)
862 {
863     SCSW *s = &sch->curr_status.scsw;
864     PMCW *p = &sch->curr_status.pmcw;
865     int ret;
866 
867     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
868         ret = -ENODEV;
869         goto out;
870     }
871 
872     if (((s->ctrl & SCSW_CTRL_MASK_STCTL) == SCSW_STCTL_STATUS_PEND) ||
873         (s->ctrl & (SCSW_STCTL_PRIMARY |
874                     SCSW_STCTL_SECONDARY |
875                     SCSW_STCTL_ALERT))) {
876         ret = -EINPROGRESS;
877         goto out;
878     }
879 
880     if (s->ctrl & (SCSW_FCTL_HALT_FUNC | SCSW_FCTL_CLEAR_FUNC)) {
881         ret = -EBUSY;
882         goto out;
883     }
884 
885     /* Trigger the halt function. */
886     s->ctrl |= SCSW_FCTL_HALT_FUNC;
887     s->ctrl &= ~SCSW_FCTL_START_FUNC;
888     if (((s->ctrl & SCSW_CTRL_MASK_ACTL) ==
889          (SCSW_ACTL_SUBCH_ACTIVE | SCSW_ACTL_DEVICE_ACTIVE)) &&
890         ((s->ctrl & SCSW_CTRL_MASK_STCTL) == SCSW_STCTL_INTERMEDIATE)) {
891         s->ctrl &= ~SCSW_STCTL_STATUS_PEND;
892     }
893     s->ctrl |= SCSW_ACTL_HALT_PEND;
894 
895     do_subchannel_work(sch, NULL);
896     ret = 0;
897 
898 out:
899     return ret;
900 }
901 
902 static void css_update_chnmon(SubchDev *sch)
903 {
904     if (!(sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_MME)) {
905         /* Not active. */
906         return;
907     }
908     /* The counter is conveniently located at the beginning of the struct. */
909     if (sch->curr_status.pmcw.chars & PMCW_CHARS_MASK_MBFC) {
910         /* Format 1, per-subchannel area. */
911         uint32_t count;
912 
913         count = address_space_ldl(&address_space_memory,
914                                   sch->curr_status.mba,
915                                   MEMTXATTRS_UNSPECIFIED,
916                                   NULL);
917         count++;
918         address_space_stl(&address_space_memory, sch->curr_status.mba, count,
919                           MEMTXATTRS_UNSPECIFIED, NULL);
920     } else {
921         /* Format 0, global area. */
922         uint32_t offset;
923         uint16_t count;
924 
925         offset = sch->curr_status.pmcw.mbi << 5;
926         count = address_space_lduw(&address_space_memory,
927                                    channel_subsys.chnmon_area + offset,
928                                    MEMTXATTRS_UNSPECIFIED,
929                                    NULL);
930         count++;
931         address_space_stw(&address_space_memory,
932                           channel_subsys.chnmon_area + offset, count,
933                           MEMTXATTRS_UNSPECIFIED, NULL);
934     }
935 }
936 
937 int css_do_ssch(SubchDev *sch, ORB *orb)
938 {
939     SCSW *s = &sch->curr_status.scsw;
940     PMCW *p = &sch->curr_status.pmcw;
941     int ret;
942 
943     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
944         ret = -ENODEV;
945         goto out;
946     }
947 
948     if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
949         ret = -EINPROGRESS;
950         goto out;
951     }
952 
953     if (s->ctrl & (SCSW_FCTL_START_FUNC |
954                    SCSW_FCTL_HALT_FUNC |
955                    SCSW_FCTL_CLEAR_FUNC)) {
956         ret = -EBUSY;
957         goto out;
958     }
959 
960     /* If monitoring is active, update counter. */
961     if (channel_subsys.chnmon_active) {
962         css_update_chnmon(sch);
963     }
964     sch->channel_prog = orb->cpa;
965     /* Trigger the start function. */
966     s->ctrl |= (SCSW_FCTL_START_FUNC | SCSW_ACTL_START_PEND);
967     s->flags &= ~SCSW_FLAGS_MASK_PNO;
968 
969     do_subchannel_work(sch, orb);
970     ret = 0;
971 
972 out:
973     return ret;
974 }
975 
976 static void copy_irb_to_guest(IRB *dest, const IRB *src, PMCW *pmcw,
977                               int *irb_len)
978 {
979     int i;
980     uint16_t stctl = src->scsw.ctrl & SCSW_CTRL_MASK_STCTL;
981     uint16_t actl = src->scsw.ctrl & SCSW_CTRL_MASK_ACTL;
982 
983     copy_scsw_to_guest(&dest->scsw, &src->scsw);
984 
985     for (i = 0; i < ARRAY_SIZE(dest->esw); i++) {
986         dest->esw[i] = cpu_to_be32(src->esw[i]);
987     }
988     for (i = 0; i < ARRAY_SIZE(dest->ecw); i++) {
989         dest->ecw[i] = cpu_to_be32(src->ecw[i]);
990     }
991     *irb_len = sizeof(*dest) - sizeof(dest->emw);
992 
993     /* extended measurements enabled? */
994     if ((src->scsw.flags & SCSW_FLAGS_MASK_ESWF) ||
995         !(pmcw->flags & PMCW_FLAGS_MASK_TF) ||
996         !(pmcw->chars & PMCW_CHARS_MASK_XMWME)) {
997         return;
998     }
999     /* extended measurements pending? */
1000     if (!(stctl & SCSW_STCTL_STATUS_PEND)) {
1001         return;
1002     }
1003     if ((stctl & SCSW_STCTL_PRIMARY) ||
1004         (stctl == SCSW_STCTL_SECONDARY) ||
1005         ((stctl & SCSW_STCTL_INTERMEDIATE) && (actl & SCSW_ACTL_SUSP))) {
1006         for (i = 0; i < ARRAY_SIZE(dest->emw); i++) {
1007             dest->emw[i] = cpu_to_be32(src->emw[i]);
1008         }
1009     }
1010     *irb_len = sizeof(*dest);
1011 }
1012 
1013 int css_do_tsch_get_irb(SubchDev *sch, IRB *target_irb, int *irb_len)
1014 {
1015     SCSW *s = &sch->curr_status.scsw;
1016     PMCW *p = &sch->curr_status.pmcw;
1017     uint16_t stctl;
1018     IRB irb;
1019 
1020     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1021         return 3;
1022     }
1023 
1024     stctl = s->ctrl & SCSW_CTRL_MASK_STCTL;
1025 
1026     /* Prepare the irb for the guest. */
1027     memset(&irb, 0, sizeof(IRB));
1028 
1029     /* Copy scsw from current status. */
1030     memcpy(&irb.scsw, s, sizeof(SCSW));
1031     if (stctl & SCSW_STCTL_STATUS_PEND) {
1032         if (s->cstat & (SCSW_CSTAT_DATA_CHECK |
1033                         SCSW_CSTAT_CHN_CTRL_CHK |
1034                         SCSW_CSTAT_INTF_CTRL_CHK)) {
1035             irb.scsw.flags |= SCSW_FLAGS_MASK_ESWF;
1036             irb.esw[0] = 0x04804000;
1037         } else {
1038             irb.esw[0] = 0x00800000;
1039         }
1040         /* If a unit check is pending, copy sense data. */
1041         if ((s->dstat & SCSW_DSTAT_UNIT_CHECK) &&
1042             (p->chars & PMCW_CHARS_MASK_CSENSE)) {
1043             int i;
1044 
1045             irb.scsw.flags |= SCSW_FLAGS_MASK_ESWF | SCSW_FLAGS_MASK_ECTL;
1046             /* Attention: sense_data is already BE! */
1047             memcpy(irb.ecw, sch->sense_data, sizeof(sch->sense_data));
1048             for (i = 0; i < ARRAY_SIZE(irb.ecw); i++) {
1049                 irb.ecw[i] = be32_to_cpu(irb.ecw[i]);
1050             }
1051             irb.esw[1] = 0x01000000 | (sizeof(sch->sense_data) << 8);
1052         }
1053     }
1054     /* Store the irb to the guest. */
1055     copy_irb_to_guest(target_irb, &irb, p, irb_len);
1056 
1057     return ((stctl & SCSW_STCTL_STATUS_PEND) == 0);
1058 }
1059 
1060 void css_do_tsch_update_subch(SubchDev *sch)
1061 {
1062     SCSW *s = &sch->curr_status.scsw;
1063     PMCW *p = &sch->curr_status.pmcw;
1064     uint16_t stctl;
1065     uint16_t fctl;
1066     uint16_t actl;
1067 
1068     stctl = s->ctrl & SCSW_CTRL_MASK_STCTL;
1069     fctl = s->ctrl & SCSW_CTRL_MASK_FCTL;
1070     actl = s->ctrl & SCSW_CTRL_MASK_ACTL;
1071 
1072     /* Clear conditions on subchannel, if applicable. */
1073     if (stctl & SCSW_STCTL_STATUS_PEND) {
1074         s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
1075         if ((stctl != (SCSW_STCTL_INTERMEDIATE | SCSW_STCTL_STATUS_PEND)) ||
1076             ((fctl & SCSW_FCTL_HALT_FUNC) &&
1077              (actl & SCSW_ACTL_SUSP))) {
1078             s->ctrl &= ~SCSW_CTRL_MASK_FCTL;
1079         }
1080         if (stctl != (SCSW_STCTL_INTERMEDIATE | SCSW_STCTL_STATUS_PEND)) {
1081             s->flags &= ~SCSW_FLAGS_MASK_PNO;
1082             s->ctrl &= ~(SCSW_ACTL_RESUME_PEND |
1083                          SCSW_ACTL_START_PEND |
1084                          SCSW_ACTL_HALT_PEND |
1085                          SCSW_ACTL_CLEAR_PEND |
1086                          SCSW_ACTL_SUSP);
1087         } else {
1088             if ((actl & SCSW_ACTL_SUSP) &&
1089                 (fctl & SCSW_FCTL_START_FUNC)) {
1090                 s->flags &= ~SCSW_FLAGS_MASK_PNO;
1091                 if (fctl & SCSW_FCTL_HALT_FUNC) {
1092                     s->ctrl &= ~(SCSW_ACTL_RESUME_PEND |
1093                                  SCSW_ACTL_START_PEND |
1094                                  SCSW_ACTL_HALT_PEND |
1095                                  SCSW_ACTL_CLEAR_PEND |
1096                                  SCSW_ACTL_SUSP);
1097                 } else {
1098                     s->ctrl &= ~SCSW_ACTL_RESUME_PEND;
1099                 }
1100             }
1101         }
1102         /* Clear pending sense data. */
1103         if (p->chars & PMCW_CHARS_MASK_CSENSE) {
1104             memset(sch->sense_data, 0 , sizeof(sch->sense_data));
1105         }
1106     }
1107 }
1108 
1109 static void copy_crw_to_guest(CRW *dest, const CRW *src)
1110 {
1111     dest->flags = cpu_to_be16(src->flags);
1112     dest->rsid = cpu_to_be16(src->rsid);
1113 }
1114 
1115 int css_do_stcrw(CRW *crw)
1116 {
1117     CrwContainer *crw_cont;
1118     int ret;
1119 
1120     crw_cont = QTAILQ_FIRST(&channel_subsys.pending_crws);
1121     if (crw_cont) {
1122         QTAILQ_REMOVE(&channel_subsys.pending_crws, crw_cont, sibling);
1123         copy_crw_to_guest(crw, &crw_cont->crw);
1124         g_free(crw_cont);
1125         ret = 0;
1126     } else {
1127         /* List was empty, turn crw machine checks on again. */
1128         memset(crw, 0, sizeof(*crw));
1129         channel_subsys.do_crw_mchk = true;
1130         ret = 1;
1131     }
1132 
1133     return ret;
1134 }
1135 
1136 static void copy_crw_from_guest(CRW *dest, const CRW *src)
1137 {
1138     dest->flags = be16_to_cpu(src->flags);
1139     dest->rsid = be16_to_cpu(src->rsid);
1140 }
1141 
1142 void css_undo_stcrw(CRW *crw)
1143 {
1144     CrwContainer *crw_cont;
1145 
1146     crw_cont = g_try_malloc0(sizeof(CrwContainer));
1147     if (!crw_cont) {
1148         channel_subsys.crws_lost = true;
1149         return;
1150     }
1151     copy_crw_from_guest(&crw_cont->crw, crw);
1152 
1153     QTAILQ_INSERT_HEAD(&channel_subsys.pending_crws, crw_cont, sibling);
1154 }
1155 
1156 int css_do_tpi(IOIntCode *int_code, int lowcore)
1157 {
1158     /* No pending interrupts for !KVM. */
1159     return 0;
1160  }
1161 
1162 int css_collect_chp_desc(int m, uint8_t cssid, uint8_t f_chpid, uint8_t l_chpid,
1163                          int rfmt, void *buf)
1164 {
1165     int i, desc_size;
1166     uint32_t words[8];
1167     uint32_t chpid_type_word;
1168     CssImage *css;
1169 
1170     if (!m && !cssid) {
1171         css = channel_subsys.css[channel_subsys.default_cssid];
1172     } else {
1173         css = channel_subsys.css[cssid];
1174     }
1175     if (!css) {
1176         return 0;
1177     }
1178     desc_size = 0;
1179     for (i = f_chpid; i <= l_chpid; i++) {
1180         if (css->chpids[i].in_use) {
1181             chpid_type_word = 0x80000000 | (css->chpids[i].type << 8) | i;
1182             if (rfmt == 0) {
1183                 words[0] = cpu_to_be32(chpid_type_word);
1184                 words[1] = 0;
1185                 memcpy(buf + desc_size, words, 8);
1186                 desc_size += 8;
1187             } else if (rfmt == 1) {
1188                 words[0] = cpu_to_be32(chpid_type_word);
1189                 words[1] = 0;
1190                 words[2] = 0;
1191                 words[3] = 0;
1192                 words[4] = 0;
1193                 words[5] = 0;
1194                 words[6] = 0;
1195                 words[7] = 0;
1196                 memcpy(buf + desc_size, words, 32);
1197                 desc_size += 32;
1198             }
1199         }
1200     }
1201     return desc_size;
1202 }
1203 
1204 void css_do_schm(uint8_t mbk, int update, int dct, uint64_t mbo)
1205 {
1206     /* dct is currently ignored (not really meaningful for our devices) */
1207     /* TODO: Don't ignore mbk. */
1208     if (update && !channel_subsys.chnmon_active) {
1209         /* Enable measuring. */
1210         channel_subsys.chnmon_area = mbo;
1211         channel_subsys.chnmon_active = true;
1212     }
1213     if (!update && channel_subsys.chnmon_active) {
1214         /* Disable measuring. */
1215         channel_subsys.chnmon_area = 0;
1216         channel_subsys.chnmon_active = false;
1217     }
1218 }
1219 
1220 int css_do_rsch(SubchDev *sch)
1221 {
1222     SCSW *s = &sch->curr_status.scsw;
1223     PMCW *p = &sch->curr_status.pmcw;
1224     int ret;
1225 
1226     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1227         ret = -ENODEV;
1228         goto out;
1229     }
1230 
1231     if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
1232         ret = -EINPROGRESS;
1233         goto out;
1234     }
1235 
1236     if (((s->ctrl & SCSW_CTRL_MASK_FCTL) != SCSW_FCTL_START_FUNC) ||
1237         (s->ctrl & SCSW_ACTL_RESUME_PEND) ||
1238         (!(s->ctrl & SCSW_ACTL_SUSP))) {
1239         ret = -EINVAL;
1240         goto out;
1241     }
1242 
1243     /* If monitoring is active, update counter. */
1244     if (channel_subsys.chnmon_active) {
1245         css_update_chnmon(sch);
1246     }
1247 
1248     s->ctrl |= SCSW_ACTL_RESUME_PEND;
1249     do_subchannel_work(sch, NULL);
1250     ret = 0;
1251 
1252 out:
1253     return ret;
1254 }
1255 
1256 int css_do_rchp(uint8_t cssid, uint8_t chpid)
1257 {
1258     uint8_t real_cssid;
1259 
1260     if (cssid > channel_subsys.max_cssid) {
1261         return -EINVAL;
1262     }
1263     if (channel_subsys.max_cssid == 0) {
1264         real_cssid = channel_subsys.default_cssid;
1265     } else {
1266         real_cssid = cssid;
1267     }
1268     if (!channel_subsys.css[real_cssid]) {
1269         return -EINVAL;
1270     }
1271 
1272     if (!channel_subsys.css[real_cssid]->chpids[chpid].in_use) {
1273         return -ENODEV;
1274     }
1275 
1276     if (!channel_subsys.css[real_cssid]->chpids[chpid].is_virtual) {
1277         fprintf(stderr,
1278                 "rchp unsupported for non-virtual chpid %x.%02x!\n",
1279                 real_cssid, chpid);
1280         return -ENODEV;
1281     }
1282 
1283     /* We don't really use a channel path, so we're done here. */
1284     css_queue_crw(CRW_RSC_CHP, CRW_ERC_INIT,
1285                   channel_subsys.max_cssid > 0 ? 1 : 0, chpid);
1286     if (channel_subsys.max_cssid > 0) {
1287         css_queue_crw(CRW_RSC_CHP, CRW_ERC_INIT, 0, real_cssid << 8);
1288     }
1289     return 0;
1290 }
1291 
1292 bool css_schid_final(int m, uint8_t cssid, uint8_t ssid, uint16_t schid)
1293 {
1294     SubchSet *set;
1295     uint8_t real_cssid;
1296 
1297     real_cssid = (!m && (cssid == 0)) ? channel_subsys.default_cssid : cssid;
1298     if (ssid > MAX_SSID ||
1299         !channel_subsys.css[real_cssid] ||
1300         !channel_subsys.css[real_cssid]->sch_set[ssid]) {
1301         return true;
1302     }
1303     set = channel_subsys.css[real_cssid]->sch_set[ssid];
1304     return schid > find_last_bit(set->schids_used,
1305                                  (MAX_SCHID + 1) / sizeof(unsigned long));
1306 }
1307 
1308 unsigned int css_find_free_chpid(uint8_t cssid)
1309 {
1310     CssImage *css = channel_subsys.css[cssid];
1311     unsigned int chpid;
1312 
1313     if (!css) {
1314         return MAX_CHPID + 1;
1315     }
1316 
1317     for (chpid = 0; chpid <= MAX_CHPID; chpid++) {
1318         /* skip reserved chpid */
1319         if (chpid == VIRTIO_CCW_CHPID) {
1320             continue;
1321         }
1322         if (!css->chpids[chpid].in_use) {
1323             return chpid;
1324         }
1325     }
1326     return MAX_CHPID + 1;
1327 }
1328 
1329 static int css_add_virtual_chpid(uint8_t cssid, uint8_t chpid, uint8_t type)
1330 {
1331     CssImage *css;
1332 
1333     trace_css_chpid_add(cssid, chpid, type);
1334     css = channel_subsys.css[cssid];
1335     if (!css) {
1336         return -EINVAL;
1337     }
1338     if (css->chpids[chpid].in_use) {
1339         return -EEXIST;
1340     }
1341     css->chpids[chpid].in_use = 1;
1342     css->chpids[chpid].type = type;
1343     css->chpids[chpid].is_virtual = 1;
1344 
1345     css_generate_chp_crws(cssid, chpid);
1346 
1347     return 0;
1348 }
1349 
1350 void css_sch_build_virtual_schib(SubchDev *sch, uint8_t chpid, uint8_t type)
1351 {
1352     PMCW *p = &sch->curr_status.pmcw;
1353     SCSW *s = &sch->curr_status.scsw;
1354     int i;
1355     CssImage *css = channel_subsys.css[sch->cssid];
1356 
1357     assert(css != NULL);
1358     memset(p, 0, sizeof(PMCW));
1359     p->flags |= PMCW_FLAGS_MASK_DNV;
1360     p->devno = sch->devno;
1361     /* single path */
1362     p->pim = 0x80;
1363     p->pom = 0xff;
1364     p->pam = 0x80;
1365     p->chpid[0] = chpid;
1366     if (!css->chpids[chpid].in_use) {
1367         css_add_virtual_chpid(sch->cssid, chpid, type);
1368     }
1369 
1370     memset(s, 0, sizeof(SCSW));
1371     sch->curr_status.mba = 0;
1372     for (i = 0; i < ARRAY_SIZE(sch->curr_status.mda); i++) {
1373         sch->curr_status.mda[i] = 0;
1374     }
1375 }
1376 
1377 SubchDev *css_find_subch(uint8_t m, uint8_t cssid, uint8_t ssid, uint16_t schid)
1378 {
1379     uint8_t real_cssid;
1380 
1381     real_cssid = (!m && (cssid == 0)) ? channel_subsys.default_cssid : cssid;
1382 
1383     if (!channel_subsys.css[real_cssid]) {
1384         return NULL;
1385     }
1386 
1387     if (!channel_subsys.css[real_cssid]->sch_set[ssid]) {
1388         return NULL;
1389     }
1390 
1391     return channel_subsys.css[real_cssid]->sch_set[ssid]->sch[schid];
1392 }
1393 
1394 /**
1395  * Return free device number in subchannel set.
1396  *
1397  * Return index of the first free device number in the subchannel set
1398  * identified by @p cssid and @p ssid, beginning the search at @p
1399  * start and wrapping around at MAX_DEVNO. Return a value exceeding
1400  * MAX_SCHID if there are no free device numbers in the subchannel
1401  * set.
1402  */
1403 static uint32_t css_find_free_devno(uint8_t cssid, uint8_t ssid,
1404                                     uint16_t start)
1405 {
1406     uint32_t round;
1407 
1408     for (round = 0; round <= MAX_DEVNO; round++) {
1409         uint16_t devno = (start + round) % MAX_DEVNO;
1410 
1411         if (!css_devno_used(cssid, ssid, devno)) {
1412             return devno;
1413         }
1414     }
1415     return MAX_DEVNO + 1;
1416 }
1417 
1418 /**
1419  * Return first free subchannel (id) in subchannel set.
1420  *
1421  * Return index of the first free subchannel in the subchannel set
1422  * identified by @p cssid and @p ssid, if there is any. Return a value
1423  * exceeding MAX_SCHID if there are no free subchannels in the
1424  * subchannel set.
1425  */
1426 static uint32_t css_find_free_subch(uint8_t cssid, uint8_t ssid)
1427 {
1428     uint32_t schid;
1429 
1430     for (schid = 0; schid <= MAX_SCHID; schid++) {
1431         if (!css_find_subch(1, cssid, ssid, schid)) {
1432             return schid;
1433         }
1434     }
1435     return MAX_SCHID + 1;
1436 }
1437 
1438 /**
1439  * Return first free subchannel (id) in subchannel set for a device number
1440  *
1441  * Verify the device number @p devno is not used yet in the subchannel
1442  * set identified by @p cssid and @p ssid. Set @p schid to the index
1443  * of the first free subchannel in the subchannel set, if there is
1444  * any. Return true if everything succeeded and false otherwise.
1445  */
1446 static bool css_find_free_subch_for_devno(uint8_t cssid, uint8_t ssid,
1447                                           uint16_t devno, uint16_t *schid,
1448                                           Error **errp)
1449 {
1450     uint32_t free_schid;
1451 
1452     assert(schid);
1453     if (css_devno_used(cssid, ssid, devno)) {
1454         error_setg(errp, "Device %x.%x.%04x already exists",
1455                    cssid, ssid, devno);
1456         return false;
1457     }
1458     free_schid = css_find_free_subch(cssid, ssid);
1459     if (free_schid > MAX_SCHID) {
1460         error_setg(errp, "No free subchannel found for %x.%x.%04x",
1461                    cssid, ssid, devno);
1462         return false;
1463     }
1464     *schid = free_schid;
1465     return true;
1466 }
1467 
1468 /**
1469  * Return first free subchannel (id) and device number
1470  *
1471  * Locate the first free subchannel and first free device number in
1472  * any of the subchannel sets of the channel subsystem identified by
1473  * @p cssid. Return false if no free subchannel / device number could
1474  * be found. Otherwise set @p ssid, @p devno and @p schid to identify
1475  * the available subchannel and device number and return true.
1476  *
1477  * May modify @p ssid, @p devno and / or @p schid even if no free
1478  * subchannel / device number could be found.
1479  */
1480 static bool css_find_free_subch_and_devno(uint8_t cssid, uint8_t *ssid,
1481                                           uint16_t *devno, uint16_t *schid,
1482                                           Error **errp)
1483 {
1484     uint32_t free_schid, free_devno;
1485 
1486     assert(ssid && devno && schid);
1487     for (*ssid = 0; *ssid <= MAX_SSID; (*ssid)++) {
1488         free_schid = css_find_free_subch(cssid, *ssid);
1489         if (free_schid > MAX_SCHID) {
1490             continue;
1491         }
1492         free_devno = css_find_free_devno(cssid, *ssid, free_schid);
1493         if (free_devno > MAX_DEVNO) {
1494             continue;
1495         }
1496         *schid = free_schid;
1497         *devno = free_devno;
1498         return true;
1499     }
1500     error_setg(errp, "Virtual channel subsystem is full!");
1501     return false;
1502 }
1503 
1504 bool css_subch_visible(SubchDev *sch)
1505 {
1506     if (sch->ssid > channel_subsys.max_ssid) {
1507         return false;
1508     }
1509 
1510     if (sch->cssid != channel_subsys.default_cssid) {
1511         return (channel_subsys.max_cssid > 0);
1512     }
1513 
1514     return true;
1515 }
1516 
1517 bool css_present(uint8_t cssid)
1518 {
1519     return (channel_subsys.css[cssid] != NULL);
1520 }
1521 
1522 bool css_devno_used(uint8_t cssid, uint8_t ssid, uint16_t devno)
1523 {
1524     if (!channel_subsys.css[cssid]) {
1525         return false;
1526     }
1527     if (!channel_subsys.css[cssid]->sch_set[ssid]) {
1528         return false;
1529     }
1530 
1531     return !!test_bit(devno,
1532                       channel_subsys.css[cssid]->sch_set[ssid]->devnos_used);
1533 }
1534 
1535 void css_subch_assign(uint8_t cssid, uint8_t ssid, uint16_t schid,
1536                       uint16_t devno, SubchDev *sch)
1537 {
1538     CssImage *css;
1539     SubchSet *s_set;
1540 
1541     trace_css_assign_subch(sch ? "assign" : "deassign", cssid, ssid, schid,
1542                            devno);
1543     if (!channel_subsys.css[cssid]) {
1544         fprintf(stderr,
1545                 "Suspicious call to %s (%x.%x.%04x) for non-existing css!\n",
1546                 __func__, cssid, ssid, schid);
1547         return;
1548     }
1549     css = channel_subsys.css[cssid];
1550 
1551     if (!css->sch_set[ssid]) {
1552         css->sch_set[ssid] = g_malloc0(sizeof(SubchSet));
1553     }
1554     s_set = css->sch_set[ssid];
1555 
1556     s_set->sch[schid] = sch;
1557     if (sch) {
1558         set_bit(schid, s_set->schids_used);
1559         set_bit(devno, s_set->devnos_used);
1560     } else {
1561         clear_bit(schid, s_set->schids_used);
1562         clear_bit(devno, s_set->devnos_used);
1563     }
1564 }
1565 
1566 void css_queue_crw(uint8_t rsc, uint8_t erc, int chain, uint16_t rsid)
1567 {
1568     CrwContainer *crw_cont;
1569 
1570     trace_css_crw(rsc, erc, rsid, chain ? "(chained)" : "");
1571     /* TODO: Maybe use a static crw pool? */
1572     crw_cont = g_try_malloc0(sizeof(CrwContainer));
1573     if (!crw_cont) {
1574         channel_subsys.crws_lost = true;
1575         return;
1576     }
1577     crw_cont->crw.flags = (rsc << 8) | erc;
1578     if (chain) {
1579         crw_cont->crw.flags |= CRW_FLAGS_MASK_C;
1580     }
1581     crw_cont->crw.rsid = rsid;
1582     if (channel_subsys.crws_lost) {
1583         crw_cont->crw.flags |= CRW_FLAGS_MASK_R;
1584         channel_subsys.crws_lost = false;
1585     }
1586 
1587     QTAILQ_INSERT_TAIL(&channel_subsys.pending_crws, crw_cont, sibling);
1588 
1589     if (channel_subsys.do_crw_mchk) {
1590         channel_subsys.do_crw_mchk = false;
1591         /* Inject crw pending machine check. */
1592         s390_crw_mchk();
1593     }
1594 }
1595 
1596 void css_generate_sch_crws(uint8_t cssid, uint8_t ssid, uint16_t schid,
1597                            int hotplugged, int add)
1598 {
1599     uint8_t guest_cssid;
1600     bool chain_crw;
1601 
1602     if (add && !hotplugged) {
1603         return;
1604     }
1605     if (channel_subsys.max_cssid == 0) {
1606         /* Default cssid shows up as 0. */
1607         guest_cssid = (cssid == channel_subsys.default_cssid) ? 0 : cssid;
1608     } else {
1609         /* Show real cssid to the guest. */
1610         guest_cssid = cssid;
1611     }
1612     /*
1613      * Only notify for higher subchannel sets/channel subsystems if the
1614      * guest has enabled it.
1615      */
1616     if ((ssid > channel_subsys.max_ssid) ||
1617         (guest_cssid > channel_subsys.max_cssid) ||
1618         ((channel_subsys.max_cssid == 0) &&
1619          (cssid != channel_subsys.default_cssid))) {
1620         return;
1621     }
1622     chain_crw = (channel_subsys.max_ssid > 0) ||
1623             (channel_subsys.max_cssid > 0);
1624     css_queue_crw(CRW_RSC_SUBCH, CRW_ERC_IPI, chain_crw ? 1 : 0, schid);
1625     if (chain_crw) {
1626         css_queue_crw(CRW_RSC_SUBCH, CRW_ERC_IPI, 0,
1627                       (guest_cssid << 8) | (ssid << 4));
1628     }
1629     /* RW_ERC_IPI --> clear pending interrupts */
1630     css_clear_io_interrupt(css_do_build_subchannel_id(cssid, ssid), schid);
1631 }
1632 
1633 void css_generate_chp_crws(uint8_t cssid, uint8_t chpid)
1634 {
1635     /* TODO */
1636 }
1637 
1638 void css_generate_css_crws(uint8_t cssid)
1639 {
1640     if (!channel_subsys.sei_pending) {
1641         css_queue_crw(CRW_RSC_CSS, 0, 0, cssid);
1642     }
1643     channel_subsys.sei_pending = true;
1644 }
1645 
1646 void css_clear_sei_pending(void)
1647 {
1648     channel_subsys.sei_pending = false;
1649 }
1650 
1651 int css_enable_mcsse(void)
1652 {
1653     trace_css_enable_facility("mcsse");
1654     channel_subsys.max_cssid = MAX_CSSID;
1655     return 0;
1656 }
1657 
1658 int css_enable_mss(void)
1659 {
1660     trace_css_enable_facility("mss");
1661     channel_subsys.max_ssid = MAX_SSID;
1662     return 0;
1663 }
1664 
1665 void subch_device_save(SubchDev *s, QEMUFile *f)
1666 {
1667     int i;
1668 
1669     qemu_put_byte(f, s->cssid);
1670     qemu_put_byte(f, s->ssid);
1671     qemu_put_be16(f, s->schid);
1672     qemu_put_be16(f, s->devno);
1673     qemu_put_byte(f, s->thinint_active);
1674     /* SCHIB */
1675     /*     PMCW */
1676     qemu_put_be32(f, s->curr_status.pmcw.intparm);
1677     qemu_put_be16(f, s->curr_status.pmcw.flags);
1678     qemu_put_be16(f, s->curr_status.pmcw.devno);
1679     qemu_put_byte(f, s->curr_status.pmcw.lpm);
1680     qemu_put_byte(f, s->curr_status.pmcw.pnom);
1681     qemu_put_byte(f, s->curr_status.pmcw.lpum);
1682     qemu_put_byte(f, s->curr_status.pmcw.pim);
1683     qemu_put_be16(f, s->curr_status.pmcw.mbi);
1684     qemu_put_byte(f, s->curr_status.pmcw.pom);
1685     qemu_put_byte(f, s->curr_status.pmcw.pam);
1686     qemu_put_buffer(f, s->curr_status.pmcw.chpid, 8);
1687     qemu_put_be32(f, s->curr_status.pmcw.chars);
1688     /*     SCSW */
1689     qemu_put_be16(f, s->curr_status.scsw.flags);
1690     qemu_put_be16(f, s->curr_status.scsw.ctrl);
1691     qemu_put_be32(f, s->curr_status.scsw.cpa);
1692     qemu_put_byte(f, s->curr_status.scsw.dstat);
1693     qemu_put_byte(f, s->curr_status.scsw.cstat);
1694     qemu_put_be16(f, s->curr_status.scsw.count);
1695     qemu_put_be64(f, s->curr_status.mba);
1696     qemu_put_buffer(f, s->curr_status.mda, 4);
1697     /* end SCHIB */
1698     qemu_put_buffer(f, s->sense_data, 32);
1699     qemu_put_be64(f, s->channel_prog);
1700     /* last cmd */
1701     qemu_put_byte(f, s->last_cmd.cmd_code);
1702     qemu_put_byte(f, s->last_cmd.flags);
1703     qemu_put_be16(f, s->last_cmd.count);
1704     qemu_put_be32(f, s->last_cmd.cda);
1705     qemu_put_byte(f, s->last_cmd_valid);
1706     qemu_put_byte(f, s->id.reserved);
1707     qemu_put_be16(f, s->id.cu_type);
1708     qemu_put_byte(f, s->id.cu_model);
1709     qemu_put_be16(f, s->id.dev_type);
1710     qemu_put_byte(f, s->id.dev_model);
1711     qemu_put_byte(f, s->id.unused);
1712     for (i = 0; i < ARRAY_SIZE(s->id.ciw); i++) {
1713         qemu_put_byte(f, s->id.ciw[i].type);
1714         qemu_put_byte(f, s->id.ciw[i].command);
1715         qemu_put_be16(f, s->id.ciw[i].count);
1716     }
1717     qemu_put_byte(f, s->ccw_fmt_1);
1718     qemu_put_byte(f, s->ccw_no_data_cnt);
1719 }
1720 
1721 int subch_device_load(SubchDev *s, QEMUFile *f)
1722 {
1723     SubchDev *old_s;
1724     uint16_t old_schid = s->schid;
1725     int i;
1726 
1727     s->cssid = qemu_get_byte(f);
1728     s->ssid = qemu_get_byte(f);
1729     s->schid = qemu_get_be16(f);
1730     s->devno = qemu_get_be16(f);
1731     /* Re-assign subch. */
1732     if (old_schid != s->schid) {
1733         old_s = channel_subsys.css[s->cssid]->sch_set[s->ssid]->sch[old_schid];
1734         /*
1735          * (old_s != s) means that some other device has its correct
1736          * subchannel already assigned (in load).
1737          */
1738         if (old_s == s) {
1739             css_subch_assign(s->cssid, s->ssid, old_schid, s->devno, NULL);
1740         }
1741         /* It's OK to re-assign without a prior de-assign. */
1742         css_subch_assign(s->cssid, s->ssid, s->schid, s->devno, s);
1743     }
1744     s->thinint_active = qemu_get_byte(f);
1745     /* SCHIB */
1746     /*     PMCW */
1747     s->curr_status.pmcw.intparm = qemu_get_be32(f);
1748     s->curr_status.pmcw.flags = qemu_get_be16(f);
1749     s->curr_status.pmcw.devno = qemu_get_be16(f);
1750     s->curr_status.pmcw.lpm = qemu_get_byte(f);
1751     s->curr_status.pmcw.pnom  = qemu_get_byte(f);
1752     s->curr_status.pmcw.lpum = qemu_get_byte(f);
1753     s->curr_status.pmcw.pim = qemu_get_byte(f);
1754     s->curr_status.pmcw.mbi = qemu_get_be16(f);
1755     s->curr_status.pmcw.pom = qemu_get_byte(f);
1756     s->curr_status.pmcw.pam = qemu_get_byte(f);
1757     qemu_get_buffer(f, s->curr_status.pmcw.chpid, 8);
1758     s->curr_status.pmcw.chars = qemu_get_be32(f);
1759     /*     SCSW */
1760     s->curr_status.scsw.flags = qemu_get_be16(f);
1761     s->curr_status.scsw.ctrl = qemu_get_be16(f);
1762     s->curr_status.scsw.cpa = qemu_get_be32(f);
1763     s->curr_status.scsw.dstat = qemu_get_byte(f);
1764     s->curr_status.scsw.cstat = qemu_get_byte(f);
1765     s->curr_status.scsw.count = qemu_get_be16(f);
1766     s->curr_status.mba = qemu_get_be64(f);
1767     qemu_get_buffer(f, s->curr_status.mda, 4);
1768     /* end SCHIB */
1769     qemu_get_buffer(f, s->sense_data, 32);
1770     s->channel_prog = qemu_get_be64(f);
1771     /* last cmd */
1772     s->last_cmd.cmd_code = qemu_get_byte(f);
1773     s->last_cmd.flags = qemu_get_byte(f);
1774     s->last_cmd.count = qemu_get_be16(f);
1775     s->last_cmd.cda = qemu_get_be32(f);
1776     s->last_cmd_valid = qemu_get_byte(f);
1777     s->id.reserved = qemu_get_byte(f);
1778     s->id.cu_type = qemu_get_be16(f);
1779     s->id.cu_model = qemu_get_byte(f);
1780     s->id.dev_type = qemu_get_be16(f);
1781     s->id.dev_model = qemu_get_byte(f);
1782     s->id.unused = qemu_get_byte(f);
1783     for (i = 0; i < ARRAY_SIZE(s->id.ciw); i++) {
1784         s->id.ciw[i].type = qemu_get_byte(f);
1785         s->id.ciw[i].command = qemu_get_byte(f);
1786         s->id.ciw[i].count = qemu_get_be16(f);
1787     }
1788     s->ccw_fmt_1 = qemu_get_byte(f);
1789     s->ccw_no_data_cnt = qemu_get_byte(f);
1790     /*
1791      * Hack alert. We don't migrate the channel subsystem status (no
1792      * device!), but we need to find out if the guest enabled mss/mcss-e.
1793      * If the subchannel is enabled, it certainly was able to access it,
1794      * so adjust the max_ssid/max_cssid values for relevant ssid/cssid
1795      * values. This is not watertight, but better than nothing.
1796      */
1797     if (s->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ENA) {
1798         if (s->ssid) {
1799             channel_subsys.max_ssid = MAX_SSID;
1800         }
1801         if (s->cssid != channel_subsys.default_cssid) {
1802             channel_subsys.max_cssid = MAX_CSSID;
1803         }
1804     }
1805     return 0;
1806 }
1807 
1808 void css_reset_sch(SubchDev *sch)
1809 {
1810     PMCW *p = &sch->curr_status.pmcw;
1811 
1812     if ((p->flags & PMCW_FLAGS_MASK_ENA) != 0 && sch->disable_cb) {
1813         sch->disable_cb(sch);
1814     }
1815 
1816     p->intparm = 0;
1817     p->flags &= ~(PMCW_FLAGS_MASK_ISC | PMCW_FLAGS_MASK_ENA |
1818                   PMCW_FLAGS_MASK_LM | PMCW_FLAGS_MASK_MME |
1819                   PMCW_FLAGS_MASK_MP | PMCW_FLAGS_MASK_TF);
1820     p->flags |= PMCW_FLAGS_MASK_DNV;
1821     p->devno = sch->devno;
1822     p->pim = 0x80;
1823     p->lpm = p->pim;
1824     p->pnom = 0;
1825     p->lpum = 0;
1826     p->mbi = 0;
1827     p->pom = 0xff;
1828     p->pam = 0x80;
1829     p->chars &= ~(PMCW_CHARS_MASK_MBFC | PMCW_CHARS_MASK_XMWME |
1830                   PMCW_CHARS_MASK_CSENSE);
1831 
1832     memset(&sch->curr_status.scsw, 0, sizeof(sch->curr_status.scsw));
1833     sch->curr_status.mba = 0;
1834 
1835     sch->channel_prog = 0x0;
1836     sch->last_cmd_valid = false;
1837     sch->thinint_active = false;
1838 }
1839 
1840 void css_reset(void)
1841 {
1842     CrwContainer *crw_cont;
1843 
1844     /* Clean up monitoring. */
1845     channel_subsys.chnmon_active = false;
1846     channel_subsys.chnmon_area = 0;
1847 
1848     /* Clear pending CRWs. */
1849     while ((crw_cont = QTAILQ_FIRST(&channel_subsys.pending_crws))) {
1850         QTAILQ_REMOVE(&channel_subsys.pending_crws, crw_cont, sibling);
1851         g_free(crw_cont);
1852     }
1853     channel_subsys.sei_pending = false;
1854     channel_subsys.do_crw_mchk = true;
1855     channel_subsys.crws_lost = false;
1856 
1857     /* Reset maximum ids. */
1858     channel_subsys.max_cssid = 0;
1859     channel_subsys.max_ssid = 0;
1860 }
1861 
1862 static void get_css_devid(Object *obj, Visitor *v, const char *name,
1863                           void *opaque, Error **errp)
1864 {
1865     DeviceState *dev = DEVICE(obj);
1866     Property *prop = opaque;
1867     CssDevId *dev_id = qdev_get_prop_ptr(dev, prop);
1868     char buffer[] = "xx.x.xxxx";
1869     char *p = buffer;
1870     int r;
1871 
1872     if (dev_id->valid) {
1873 
1874         r = snprintf(buffer, sizeof(buffer), "%02x.%1x.%04x", dev_id->cssid,
1875                      dev_id->ssid, dev_id->devid);
1876         assert(r == sizeof(buffer) - 1);
1877 
1878         /* drop leading zero */
1879         if (dev_id->cssid <= 0xf) {
1880             p++;
1881         }
1882     } else {
1883         snprintf(buffer, sizeof(buffer), "<unset>");
1884     }
1885 
1886     visit_type_str(v, name, &p, errp);
1887 }
1888 
1889 /*
1890  * parse <cssid>.<ssid>.<devid> and assert valid range for cssid/ssid
1891  */
1892 static void set_css_devid(Object *obj, Visitor *v, const char *name,
1893                           void *opaque, Error **errp)
1894 {
1895     DeviceState *dev = DEVICE(obj);
1896     Property *prop = opaque;
1897     CssDevId *dev_id = qdev_get_prop_ptr(dev, prop);
1898     Error *local_err = NULL;
1899     char *str;
1900     int num, n1, n2;
1901     unsigned int cssid, ssid, devid;
1902 
1903     if (dev->realized) {
1904         qdev_prop_set_after_realize(dev, name, errp);
1905         return;
1906     }
1907 
1908     visit_type_str(v, name, &str, &local_err);
1909     if (local_err) {
1910         error_propagate(errp, local_err);
1911         return;
1912     }
1913 
1914     num = sscanf(str, "%2x.%1x%n.%4x%n", &cssid, &ssid, &n1, &devid, &n2);
1915     if (num != 3 || (n2 - n1) != 5 || strlen(str) != n2) {
1916         error_set_from_qdev_prop_error(errp, EINVAL, dev, prop, str);
1917         goto out;
1918     }
1919     if ((cssid > MAX_CSSID) || (ssid > MAX_SSID)) {
1920         error_setg(errp, "Invalid cssid or ssid: cssid %x, ssid %x",
1921                    cssid, ssid);
1922         goto out;
1923     }
1924 
1925     dev_id->cssid = cssid;
1926     dev_id->ssid = ssid;
1927     dev_id->devid = devid;
1928     dev_id->valid = true;
1929 
1930 out:
1931     g_free(str);
1932 }
1933 
1934 PropertyInfo css_devid_propinfo = {
1935     .name = "str",
1936     .description = "Identifier of an I/O device in the channel "
1937                    "subsystem, example: fe.1.23ab",
1938     .get = get_css_devid,
1939     .set = set_css_devid,
1940 };
1941 
1942 PropertyInfo css_devid_ro_propinfo = {
1943     .name = "str",
1944     .description = "Read-only identifier of an I/O device in the channel "
1945                    "subsystem, example: fe.1.23ab",
1946     .get = get_css_devid,
1947 };
1948 
1949 SubchDev *css_create_virtual_sch(CssDevId bus_id, Error **errp)
1950 {
1951     uint16_t schid = 0;
1952     SubchDev *sch;
1953 
1954     if (bus_id.valid) {
1955         /* Enforce use of virtual cssid. */
1956         if (bus_id.cssid != VIRTUAL_CSSID) {
1957             error_setg(errp, "cssid %hhx not valid for virtual devices",
1958                        bus_id.cssid);
1959             return NULL;
1960         }
1961         if (!css_find_free_subch_for_devno(bus_id.cssid, bus_id.ssid,
1962                                            bus_id.devid, &schid, errp)) {
1963             return NULL;
1964         }
1965     } else {
1966         bus_id.cssid = VIRTUAL_CSSID;
1967         if (!css_find_free_subch_and_devno(bus_id.cssid, &bus_id.ssid,
1968                                            &bus_id.devid, &schid, errp)) {
1969             return NULL;
1970         }
1971     }
1972 
1973     sch = g_malloc0(sizeof(*sch));
1974     sch->cssid = bus_id.cssid;
1975     sch->ssid = bus_id.ssid;
1976     sch->devno = bus_id.devid;
1977     sch->schid = schid;
1978     css_subch_assign(sch->cssid, sch->ssid, schid, sch->devno, sch);
1979     return sch;
1980 }
1981