xref: /openbmc/qemu/hw/s390x/css.c (revision cb764d06)
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 "qemu/error-report.h"
18 #include "exec/address-spaces.h"
19 #include "cpu.h"
20 #include "hw/s390x/ioinst.h"
21 #include "hw/s390x/css.h"
22 #include "trace.h"
23 #include "hw/s390x/s390_flic.h"
24 #include "hw/s390x/s390-virtio-ccw.h"
25 
26 typedef struct CrwContainer {
27     CRW crw;
28     QTAILQ_ENTRY(CrwContainer) sibling;
29 } CrwContainer;
30 
31 static const VMStateDescription vmstate_crw = {
32     .name = "s390_crw",
33     .version_id = 1,
34     .minimum_version_id = 1,
35     .fields = (VMStateField[]) {
36         VMSTATE_UINT16(flags, CRW),
37         VMSTATE_UINT16(rsid, CRW),
38         VMSTATE_END_OF_LIST()
39     },
40 };
41 
42 static const VMStateDescription vmstate_crw_container = {
43     .name = "s390_crw_container",
44     .version_id = 1,
45     .minimum_version_id = 1,
46     .fields = (VMStateField[]) {
47         VMSTATE_STRUCT(crw, CrwContainer, 0, vmstate_crw, CRW),
48         VMSTATE_END_OF_LIST()
49     },
50 };
51 
52 typedef struct ChpInfo {
53     uint8_t in_use;
54     uint8_t type;
55     uint8_t is_virtual;
56 } ChpInfo;
57 
58 static const VMStateDescription vmstate_chp_info = {
59     .name = "s390_chp_info",
60     .version_id = 1,
61     .minimum_version_id = 1,
62     .fields = (VMStateField[]) {
63         VMSTATE_UINT8(in_use, ChpInfo),
64         VMSTATE_UINT8(type, ChpInfo),
65         VMSTATE_UINT8(is_virtual, ChpInfo),
66         VMSTATE_END_OF_LIST()
67     }
68 };
69 
70 typedef struct SubchSet {
71     SubchDev *sch[MAX_SCHID + 1];
72     unsigned long schids_used[BITS_TO_LONGS(MAX_SCHID + 1)];
73     unsigned long devnos_used[BITS_TO_LONGS(MAX_SCHID + 1)];
74 } SubchSet;
75 
76 static const VMStateDescription vmstate_scsw = {
77     .name = "s390_scsw",
78     .version_id = 1,
79     .minimum_version_id = 1,
80     .fields = (VMStateField[]) {
81         VMSTATE_UINT16(flags, SCSW),
82         VMSTATE_UINT16(ctrl, SCSW),
83         VMSTATE_UINT32(cpa, SCSW),
84         VMSTATE_UINT8(dstat, SCSW),
85         VMSTATE_UINT8(cstat, SCSW),
86         VMSTATE_UINT16(count, SCSW),
87         VMSTATE_END_OF_LIST()
88     }
89 };
90 
91 static const VMStateDescription vmstate_pmcw = {
92     .name = "s390_pmcw",
93     .version_id = 1,
94     .minimum_version_id = 1,
95     .fields = (VMStateField[]) {
96         VMSTATE_UINT32(intparm, PMCW),
97         VMSTATE_UINT16(flags, PMCW),
98         VMSTATE_UINT16(devno, PMCW),
99         VMSTATE_UINT8(lpm, PMCW),
100         VMSTATE_UINT8(pnom, PMCW),
101         VMSTATE_UINT8(lpum, PMCW),
102         VMSTATE_UINT8(pim, PMCW),
103         VMSTATE_UINT16(mbi, PMCW),
104         VMSTATE_UINT8(pom, PMCW),
105         VMSTATE_UINT8(pam, PMCW),
106         VMSTATE_UINT8_ARRAY(chpid, PMCW, 8),
107         VMSTATE_UINT32(chars, PMCW),
108         VMSTATE_END_OF_LIST()
109     }
110 };
111 
112 static const VMStateDescription vmstate_schib = {
113     .name = "s390_schib",
114     .version_id = 1,
115     .minimum_version_id = 1,
116     .fields = (VMStateField[]) {
117         VMSTATE_STRUCT(pmcw, SCHIB, 0, vmstate_pmcw, PMCW),
118         VMSTATE_STRUCT(scsw, SCHIB, 0, vmstate_scsw, SCSW),
119         VMSTATE_UINT64(mba, SCHIB),
120         VMSTATE_UINT8_ARRAY(mda, SCHIB, 4),
121         VMSTATE_END_OF_LIST()
122     }
123 };
124 
125 
126 static const VMStateDescription vmstate_ccw1 = {
127     .name = "s390_ccw1",
128     .version_id = 1,
129     .minimum_version_id = 1,
130     .fields = (VMStateField[]) {
131         VMSTATE_UINT8(cmd_code, CCW1),
132         VMSTATE_UINT8(flags, CCW1),
133         VMSTATE_UINT16(count, CCW1),
134         VMSTATE_UINT32(cda, CCW1),
135         VMSTATE_END_OF_LIST()
136     }
137 };
138 
139 static const VMStateDescription vmstate_ciw = {
140     .name = "s390_ciw",
141     .version_id = 1,
142     .minimum_version_id = 1,
143     .fields = (VMStateField[]) {
144         VMSTATE_UINT8(type, CIW),
145         VMSTATE_UINT8(command, CIW),
146         VMSTATE_UINT16(count, CIW),
147         VMSTATE_END_OF_LIST()
148     }
149 };
150 
151 static const VMStateDescription vmstate_sense_id = {
152     .name = "s390_sense_id",
153     .version_id = 1,
154     .minimum_version_id = 1,
155     .fields = (VMStateField[]) {
156         VMSTATE_UINT8(reserved, SenseId),
157         VMSTATE_UINT16(cu_type, SenseId),
158         VMSTATE_UINT8(cu_model, SenseId),
159         VMSTATE_UINT16(dev_type, SenseId),
160         VMSTATE_UINT8(dev_model, SenseId),
161         VMSTATE_UINT8(unused, SenseId),
162         VMSTATE_STRUCT_ARRAY(ciw, SenseId, MAX_CIWS, 0, vmstate_ciw, CIW),
163         VMSTATE_END_OF_LIST()
164     }
165 };
166 
167 static const VMStateDescription vmstate_orb = {
168     .name = "s390_orb",
169     .version_id = 1,
170     .minimum_version_id = 1,
171     .fields = (VMStateField[]) {
172         VMSTATE_UINT32(intparm, ORB),
173         VMSTATE_UINT16(ctrl0, ORB),
174         VMSTATE_UINT8(lpm, ORB),
175         VMSTATE_UINT8(ctrl1, ORB),
176         VMSTATE_UINT32(cpa, ORB),
177         VMSTATE_END_OF_LIST()
178     }
179 };
180 
181 static bool vmstate_schdev_orb_needed(void *opaque)
182 {
183     return css_migration_enabled();
184 }
185 
186 static const VMStateDescription vmstate_schdev_orb = {
187     .name = "s390_subch_dev/orb",
188     .version_id = 1,
189     .minimum_version_id = 1,
190     .needed = vmstate_schdev_orb_needed,
191     .fields = (VMStateField[]) {
192         VMSTATE_STRUCT(orb, SubchDev, 1, vmstate_orb, ORB),
193         VMSTATE_END_OF_LIST()
194     }
195 };
196 
197 static int subch_dev_post_load(void *opaque, int version_id);
198 static int subch_dev_pre_save(void *opaque);
199 
200 const char err_hint_devno[] = "Devno mismatch, tried to load wrong section!"
201     " Likely reason: some sequences of plug and unplug  can break"
202     " migration for machine versions prior to  2.7 (known design flaw).";
203 
204 const VMStateDescription vmstate_subch_dev = {
205     .name = "s390_subch_dev",
206     .version_id = 1,
207     .minimum_version_id = 1,
208     .post_load = subch_dev_post_load,
209     .pre_save = subch_dev_pre_save,
210     .fields = (VMStateField[]) {
211         VMSTATE_UINT8_EQUAL(cssid, SubchDev, "Bug!"),
212         VMSTATE_UINT8_EQUAL(ssid, SubchDev, "Bug!"),
213         VMSTATE_UINT16(migrated_schid, SubchDev),
214         VMSTATE_UINT16_EQUAL(devno, SubchDev, err_hint_devno),
215         VMSTATE_BOOL(thinint_active, SubchDev),
216         VMSTATE_STRUCT(curr_status, SubchDev, 0, vmstate_schib, SCHIB),
217         VMSTATE_UINT8_ARRAY(sense_data, SubchDev, 32),
218         VMSTATE_UINT64(channel_prog, SubchDev),
219         VMSTATE_STRUCT(last_cmd, SubchDev, 0, vmstate_ccw1, CCW1),
220         VMSTATE_BOOL(last_cmd_valid, SubchDev),
221         VMSTATE_STRUCT(id, SubchDev, 0, vmstate_sense_id, SenseId),
222         VMSTATE_BOOL(ccw_fmt_1, SubchDev),
223         VMSTATE_UINT8(ccw_no_data_cnt, SubchDev),
224         VMSTATE_END_OF_LIST()
225     },
226     .subsections = (const VMStateDescription * []) {
227         &vmstate_schdev_orb,
228         NULL
229     }
230 };
231 
232 typedef struct IndAddrPtrTmp {
233     IndAddr **parent;
234     uint64_t addr;
235     int32_t len;
236 } IndAddrPtrTmp;
237 
238 static int post_load_ind_addr(void *opaque, int version_id)
239 {
240     IndAddrPtrTmp *ptmp = opaque;
241     IndAddr **ind_addr = ptmp->parent;
242 
243     if (ptmp->len != 0) {
244         *ind_addr = get_indicator(ptmp->addr, ptmp->len);
245     } else {
246         *ind_addr = NULL;
247     }
248     return 0;
249 }
250 
251 static int pre_save_ind_addr(void *opaque)
252 {
253     IndAddrPtrTmp *ptmp = opaque;
254     IndAddr *ind_addr = *(ptmp->parent);
255 
256     if (ind_addr != NULL) {
257         ptmp->len = ind_addr->len;
258         ptmp->addr = ind_addr->addr;
259     } else {
260         ptmp->len = 0;
261         ptmp->addr = 0L;
262     }
263 
264     return 0;
265 }
266 
267 const VMStateDescription vmstate_ind_addr_tmp = {
268     .name = "s390_ind_addr_tmp",
269     .pre_save = pre_save_ind_addr,
270     .post_load = post_load_ind_addr,
271 
272     .fields = (VMStateField[]) {
273         VMSTATE_INT32(len, IndAddrPtrTmp),
274         VMSTATE_UINT64(addr, IndAddrPtrTmp),
275         VMSTATE_END_OF_LIST()
276     }
277 };
278 
279 const VMStateDescription vmstate_ind_addr = {
280     .name = "s390_ind_addr_tmp",
281     .fields = (VMStateField[]) {
282         VMSTATE_WITH_TMP(IndAddr*, IndAddrPtrTmp, vmstate_ind_addr_tmp),
283         VMSTATE_END_OF_LIST()
284     }
285 };
286 
287 typedef struct CssImage {
288     SubchSet *sch_set[MAX_SSID + 1];
289     ChpInfo chpids[MAX_CHPID + 1];
290 } CssImage;
291 
292 static const VMStateDescription vmstate_css_img = {
293     .name = "s390_css_img",
294     .version_id = 1,
295     .minimum_version_id = 1,
296     .fields = (VMStateField[]) {
297         /* Subchannel sets have no relevant state. */
298         VMSTATE_STRUCT_ARRAY(chpids, CssImage, MAX_CHPID + 1, 0,
299                              vmstate_chp_info, ChpInfo),
300         VMSTATE_END_OF_LIST()
301     }
302 
303 };
304 
305 typedef struct IoAdapter {
306     uint32_t id;
307     uint8_t type;
308     uint8_t isc;
309     uint8_t flags;
310 } IoAdapter;
311 
312 typedef struct ChannelSubSys {
313     QTAILQ_HEAD(, CrwContainer) pending_crws;
314     bool sei_pending;
315     bool do_crw_mchk;
316     bool crws_lost;
317     uint8_t max_cssid;
318     uint8_t max_ssid;
319     bool chnmon_active;
320     uint64_t chnmon_area;
321     CssImage *css[MAX_CSSID + 1];
322     uint8_t default_cssid;
323     /* don't migrate, see css_register_io_adapters */
324     IoAdapter *io_adapters[CSS_IO_ADAPTER_TYPE_NUMS][MAX_ISC + 1];
325     /* don't migrate, see get_indicator and IndAddrPtrTmp */
326     QTAILQ_HEAD(, IndAddr) indicator_addresses;
327 } ChannelSubSys;
328 
329 static const VMStateDescription vmstate_css = {
330     .name = "s390_css",
331     .version_id = 1,
332     .minimum_version_id = 1,
333     .fields = (VMStateField[]) {
334         VMSTATE_QTAILQ_V(pending_crws, ChannelSubSys, 1, vmstate_crw_container,
335                          CrwContainer, sibling),
336         VMSTATE_BOOL(sei_pending, ChannelSubSys),
337         VMSTATE_BOOL(do_crw_mchk, ChannelSubSys),
338         VMSTATE_BOOL(crws_lost, ChannelSubSys),
339         /* These were kind of migrated by virtio */
340         VMSTATE_UINT8(max_cssid, ChannelSubSys),
341         VMSTATE_UINT8(max_ssid, ChannelSubSys),
342         VMSTATE_BOOL(chnmon_active, ChannelSubSys),
343         VMSTATE_UINT64(chnmon_area, ChannelSubSys),
344         VMSTATE_ARRAY_OF_POINTER_TO_STRUCT(css, ChannelSubSys, MAX_CSSID + 1,
345                 0, vmstate_css_img, CssImage),
346         VMSTATE_UINT8(default_cssid, ChannelSubSys),
347         VMSTATE_END_OF_LIST()
348     }
349 };
350 
351 static ChannelSubSys channel_subsys = {
352     .pending_crws = QTAILQ_HEAD_INITIALIZER(channel_subsys.pending_crws),
353     .do_crw_mchk = true,
354     .sei_pending = false,
355     .do_crw_mchk = true,
356     .crws_lost = false,
357     .chnmon_active = false,
358     .indicator_addresses =
359         QTAILQ_HEAD_INITIALIZER(channel_subsys.indicator_addresses),
360 };
361 
362 static int subch_dev_pre_save(void *opaque)
363 {
364     SubchDev *s = opaque;
365 
366     /* Prepare remote_schid for save */
367     s->migrated_schid = s->schid;
368 
369     return 0;
370 }
371 
372 static int subch_dev_post_load(void *opaque, int version_id)
373 {
374 
375     SubchDev *s = opaque;
376 
377     /* Re-assign the subchannel to remote_schid if necessary */
378     if (s->migrated_schid != s->schid) {
379         if (css_find_subch(true, s->cssid, s->ssid, s->schid) == s) {
380             /*
381              * Cleanup the slot before moving to s->migrated_schid provided
382              * it still belongs to us, i.e. it was not changed by previous
383              * invocation of this function.
384              */
385             css_subch_assign(s->cssid, s->ssid, s->schid, s->devno, NULL);
386         }
387         /* It's OK to re-assign without a prior de-assign. */
388         s->schid = s->migrated_schid;
389         css_subch_assign(s->cssid, s->ssid, s->schid, s->devno, s);
390     }
391 
392     if (css_migration_enabled()) {
393         /* No compat voodoo to do ;) */
394         return 0;
395     }
396     /*
397      * Hack alert. If we don't migrate the channel subsystem status
398      * we still need to find out if the guest enabled mss/mcss-e.
399      * If the subchannel is enabled, it certainly was able to access it,
400      * so adjust the max_ssid/max_cssid values for relevant ssid/cssid
401      * values. This is not watertight, but better than nothing.
402      */
403     if (s->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ENA) {
404         if (s->ssid) {
405             channel_subsys.max_ssid = MAX_SSID;
406         }
407         if (s->cssid != channel_subsys.default_cssid) {
408             channel_subsys.max_cssid = MAX_CSSID;
409         }
410     }
411     return 0;
412 }
413 
414 void css_register_vmstate(void)
415 {
416     vmstate_register(NULL, 0, &vmstate_css, &channel_subsys);
417 }
418 
419 IndAddr *get_indicator(hwaddr ind_addr, int len)
420 {
421     IndAddr *indicator;
422 
423     QTAILQ_FOREACH(indicator, &channel_subsys.indicator_addresses, sibling) {
424         if (indicator->addr == ind_addr) {
425             indicator->refcnt++;
426             return indicator;
427         }
428     }
429     indicator = g_new0(IndAddr, 1);
430     indicator->addr = ind_addr;
431     indicator->len = len;
432     indicator->refcnt = 1;
433     QTAILQ_INSERT_TAIL(&channel_subsys.indicator_addresses,
434                        indicator, sibling);
435     return indicator;
436 }
437 
438 static int s390_io_adapter_map(AdapterInfo *adapter, uint64_t map_addr,
439                                bool do_map)
440 {
441     S390FLICState *fs = s390_get_flic();
442     S390FLICStateClass *fsc = s390_get_flic_class(fs);
443 
444     return fsc->io_adapter_map(fs, adapter->adapter_id, map_addr, do_map);
445 }
446 
447 void release_indicator(AdapterInfo *adapter, IndAddr *indicator)
448 {
449     assert(indicator->refcnt > 0);
450     indicator->refcnt--;
451     if (indicator->refcnt > 0) {
452         return;
453     }
454     QTAILQ_REMOVE(&channel_subsys.indicator_addresses, indicator, sibling);
455     if (indicator->map) {
456         s390_io_adapter_map(adapter, indicator->map, false);
457     }
458     g_free(indicator);
459 }
460 
461 int map_indicator(AdapterInfo *adapter, IndAddr *indicator)
462 {
463     int ret;
464 
465     if (indicator->map) {
466         return 0; /* already mapped is not an error */
467     }
468     indicator->map = indicator->addr;
469     ret = s390_io_adapter_map(adapter, indicator->map, true);
470     if ((ret != 0) && (ret != -ENOSYS)) {
471         goto out_err;
472     }
473     return 0;
474 
475 out_err:
476     indicator->map = 0;
477     return ret;
478 }
479 
480 int css_create_css_image(uint8_t cssid, bool default_image)
481 {
482     trace_css_new_image(cssid, default_image ? "(default)" : "");
483     /* 255 is reserved */
484     if (cssid == 255) {
485         return -EINVAL;
486     }
487     if (channel_subsys.css[cssid]) {
488         return -EBUSY;
489     }
490     channel_subsys.css[cssid] = g_new0(CssImage, 1);
491     if (default_image) {
492         channel_subsys.default_cssid = cssid;
493     }
494     return 0;
495 }
496 
497 uint32_t css_get_adapter_id(CssIoAdapterType type, uint8_t isc)
498 {
499     if (type >= CSS_IO_ADAPTER_TYPE_NUMS || isc > MAX_ISC ||
500         !channel_subsys.io_adapters[type][isc]) {
501         return -1;
502     }
503 
504     return channel_subsys.io_adapters[type][isc]->id;
505 }
506 
507 /**
508  * css_register_io_adapters: Register I/O adapters per ISC during init
509  *
510  * @swap: an indication if byte swap is needed.
511  * @maskable: an indication if the adapter is subject to the mask operation.
512  * @flags: further characteristics of the adapter.
513  *         e.g. suppressible, an indication if the adapter is subject to AIS.
514  * @errp: location to store error information.
515  */
516 void css_register_io_adapters(CssIoAdapterType type, bool swap, bool maskable,
517                               uint8_t flags, Error **errp)
518 {
519     uint32_t id;
520     int ret, isc;
521     IoAdapter *adapter;
522     S390FLICState *fs = s390_get_flic();
523     S390FLICStateClass *fsc = s390_get_flic_class(fs);
524 
525     /*
526      * Disallow multiple registrations for the same device type.
527      * Report an error if registering for an already registered type.
528      */
529     if (channel_subsys.io_adapters[type][0]) {
530         error_setg(errp, "Adapters for type %d already registered", type);
531     }
532 
533     for (isc = 0; isc <= MAX_ISC; isc++) {
534         id = (type << 3) | isc;
535         ret = fsc->register_io_adapter(fs, id, isc, swap, maskable, flags);
536         if (ret == 0) {
537             adapter = g_new0(IoAdapter, 1);
538             adapter->id = id;
539             adapter->isc = isc;
540             adapter->type = type;
541             adapter->flags = flags;
542             channel_subsys.io_adapters[type][isc] = adapter;
543         } else {
544             error_setg_errno(errp, -ret, "Unexpected error %d when "
545                              "registering adapter %d", ret, id);
546             break;
547         }
548     }
549 
550     /*
551      * No need to free registered adapters in kvm: kvm will clean up
552      * when the machine goes away.
553      */
554     if (ret) {
555         for (isc--; isc >= 0; isc--) {
556             g_free(channel_subsys.io_adapters[type][isc]);
557             channel_subsys.io_adapters[type][isc] = NULL;
558         }
559     }
560 
561 }
562 
563 static void css_clear_io_interrupt(uint16_t subchannel_id,
564                                    uint16_t subchannel_nr)
565 {
566     Error *err = NULL;
567     static bool no_clear_irq;
568     S390FLICState *fs = s390_get_flic();
569     S390FLICStateClass *fsc = s390_get_flic_class(fs);
570     int r;
571 
572     if (unlikely(no_clear_irq)) {
573         return;
574     }
575     r = fsc->clear_io_irq(fs, subchannel_id, subchannel_nr);
576     switch (r) {
577     case 0:
578         break;
579     case -ENOSYS:
580         no_clear_irq = true;
581         /*
582         * Ignore unavailability, as the user can't do anything
583         * about it anyway.
584         */
585         break;
586     default:
587         error_setg_errno(&err, -r, "unexpected error condition");
588         error_propagate(&error_abort, err);
589     }
590 }
591 
592 static inline uint16_t css_do_build_subchannel_id(uint8_t cssid, uint8_t ssid)
593 {
594     if (channel_subsys.max_cssid > 0) {
595         return (cssid << 8) | (1 << 3) | (ssid << 1) | 1;
596     }
597     return (ssid << 1) | 1;
598 }
599 
600 uint16_t css_build_subchannel_id(SubchDev *sch)
601 {
602     return css_do_build_subchannel_id(sch->cssid, sch->ssid);
603 }
604 
605 void css_inject_io_interrupt(SubchDev *sch)
606 {
607     uint8_t isc = (sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ISC) >> 11;
608 
609     trace_css_io_interrupt(sch->cssid, sch->ssid, sch->schid,
610                            sch->curr_status.pmcw.intparm, isc, "");
611     s390_io_interrupt(css_build_subchannel_id(sch),
612                       sch->schid,
613                       sch->curr_status.pmcw.intparm,
614                       isc << 27);
615 }
616 
617 void css_conditional_io_interrupt(SubchDev *sch)
618 {
619     /*
620      * If the subchannel is not enabled, it is not made status pending
621      * (see PoP p. 16-17, "Status Control").
622      */
623     if (!(sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ENA)) {
624         return;
625     }
626 
627     /*
628      * If the subchannel is not currently status pending, make it pending
629      * with alert status.
630      */
631     if (!(sch->curr_status.scsw.ctrl & SCSW_STCTL_STATUS_PEND)) {
632         uint8_t isc = (sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ISC) >> 11;
633 
634         trace_css_io_interrupt(sch->cssid, sch->ssid, sch->schid,
635                                sch->curr_status.pmcw.intparm, isc,
636                                "(unsolicited)");
637         sch->curr_status.scsw.ctrl &= ~SCSW_CTRL_MASK_STCTL;
638         sch->curr_status.scsw.ctrl |=
639             SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
640         /* Inject an I/O interrupt. */
641         s390_io_interrupt(css_build_subchannel_id(sch),
642                           sch->schid,
643                           sch->curr_status.pmcw.intparm,
644                           isc << 27);
645     }
646 }
647 
648 int css_do_sic(CPUS390XState *env, uint8_t isc, uint16_t mode)
649 {
650     S390FLICState *fs = s390_get_flic();
651     S390FLICStateClass *fsc = s390_get_flic_class(fs);
652     int r;
653 
654     if (env->psw.mask & PSW_MASK_PSTATE) {
655         r = -PGM_PRIVILEGED;
656         goto out;
657     }
658 
659     trace_css_do_sic(mode, isc);
660     switch (mode) {
661     case SIC_IRQ_MODE_ALL:
662     case SIC_IRQ_MODE_SINGLE:
663         break;
664     default:
665         r = -PGM_OPERAND;
666         goto out;
667     }
668 
669     r = fsc->modify_ais_mode(fs, isc, mode) ? -PGM_OPERATION : 0;
670 out:
671     return r;
672 }
673 
674 void css_adapter_interrupt(CssIoAdapterType type, uint8_t isc)
675 {
676     S390FLICState *fs = s390_get_flic();
677     S390FLICStateClass *fsc = s390_get_flic_class(fs);
678     uint32_t io_int_word = (isc << 27) | IO_INT_WORD_AI;
679     IoAdapter *adapter = channel_subsys.io_adapters[type][isc];
680 
681     if (!adapter) {
682         return;
683     }
684 
685     trace_css_adapter_interrupt(isc);
686     if (fs->ais_supported) {
687         if (fsc->inject_airq(fs, type, isc, adapter->flags)) {
688             error_report("Failed to inject airq with AIS supported");
689             exit(1);
690         }
691     } else {
692         s390_io_interrupt(0, 0, 0, io_int_word);
693     }
694 }
695 
696 static void sch_handle_clear_func(SubchDev *sch)
697 {
698     PMCW *p = &sch->curr_status.pmcw;
699     SCSW *s = &sch->curr_status.scsw;
700     int path;
701 
702     /* Path management: In our simple css, we always choose the only path. */
703     path = 0x80;
704 
705     /* Reset values prior to 'issuing the clear signal'. */
706     p->lpum = 0;
707     p->pom = 0xff;
708     s->flags &= ~SCSW_FLAGS_MASK_PNO;
709 
710     /* We always 'attempt to issue the clear signal', and we always succeed. */
711     sch->channel_prog = 0x0;
712     sch->last_cmd_valid = false;
713     s->ctrl &= ~SCSW_ACTL_CLEAR_PEND;
714     s->ctrl |= SCSW_STCTL_STATUS_PEND;
715 
716     s->dstat = 0;
717     s->cstat = 0;
718     p->lpum = path;
719 
720 }
721 
722 static void sch_handle_halt_func(SubchDev *sch)
723 {
724 
725     PMCW *p = &sch->curr_status.pmcw;
726     SCSW *s = &sch->curr_status.scsw;
727     hwaddr curr_ccw = sch->channel_prog;
728     int path;
729 
730     /* Path management: In our simple css, we always choose the only path. */
731     path = 0x80;
732 
733     /* We always 'attempt to issue the halt signal', and we always succeed. */
734     sch->channel_prog = 0x0;
735     sch->last_cmd_valid = false;
736     s->ctrl &= ~SCSW_ACTL_HALT_PEND;
737     s->ctrl |= SCSW_STCTL_STATUS_PEND;
738 
739     if ((s->ctrl & (SCSW_ACTL_SUBCH_ACTIVE | SCSW_ACTL_DEVICE_ACTIVE)) ||
740         !((s->ctrl & SCSW_ACTL_START_PEND) ||
741           (s->ctrl & SCSW_ACTL_SUSP))) {
742         s->dstat = SCSW_DSTAT_DEVICE_END;
743     }
744     if ((s->ctrl & (SCSW_ACTL_SUBCH_ACTIVE | SCSW_ACTL_DEVICE_ACTIVE)) ||
745         (s->ctrl & SCSW_ACTL_SUSP)) {
746         s->cpa = curr_ccw + 8;
747     }
748     s->cstat = 0;
749     p->lpum = path;
750 
751 }
752 
753 static void copy_sense_id_to_guest(SenseId *dest, SenseId *src)
754 {
755     int i;
756 
757     dest->reserved = src->reserved;
758     dest->cu_type = cpu_to_be16(src->cu_type);
759     dest->cu_model = src->cu_model;
760     dest->dev_type = cpu_to_be16(src->dev_type);
761     dest->dev_model = src->dev_model;
762     dest->unused = src->unused;
763     for (i = 0; i < ARRAY_SIZE(dest->ciw); i++) {
764         dest->ciw[i].type = src->ciw[i].type;
765         dest->ciw[i].command = src->ciw[i].command;
766         dest->ciw[i].count = cpu_to_be16(src->ciw[i].count);
767     }
768 }
769 
770 static CCW1 copy_ccw_from_guest(hwaddr addr, bool fmt1)
771 {
772     CCW0 tmp0;
773     CCW1 tmp1;
774     CCW1 ret;
775 
776     if (fmt1) {
777         cpu_physical_memory_read(addr, &tmp1, sizeof(tmp1));
778         ret.cmd_code = tmp1.cmd_code;
779         ret.flags = tmp1.flags;
780         ret.count = be16_to_cpu(tmp1.count);
781         ret.cda = be32_to_cpu(tmp1.cda);
782     } else {
783         cpu_physical_memory_read(addr, &tmp0, sizeof(tmp0));
784         if ((tmp0.cmd_code & 0x0f) == CCW_CMD_TIC) {
785             ret.cmd_code = CCW_CMD_TIC;
786             ret.flags = 0;
787             ret.count = 0;
788         } else {
789             ret.cmd_code = tmp0.cmd_code;
790             ret.flags = tmp0.flags;
791             ret.count = be16_to_cpu(tmp0.count);
792         }
793         ret.cda = be16_to_cpu(tmp0.cda1) | (tmp0.cda0 << 16);
794     }
795     return ret;
796 }
797 /**
798  * If out of bounds marks the stream broken. If broken returns -EINVAL,
799  * otherwise the requested length (may be zero)
800  */
801 static inline int cds_check_len(CcwDataStream *cds, int len)
802 {
803     if (cds->at_byte + len > cds->count) {
804         cds->flags |= CDS_F_STREAM_BROKEN;
805     }
806     return cds->flags & CDS_F_STREAM_BROKEN ? -EINVAL : len;
807 }
808 
809 static inline bool cds_ccw_addrs_ok(hwaddr addr, int len, bool ccw_fmt1)
810 {
811     return (addr + len) < (ccw_fmt1 ? (1UL << 31) : (1UL << 24));
812 }
813 
814 static int ccw_dstream_rw_noflags(CcwDataStream *cds, void *buff, int len,
815                                   CcwDataStreamOp op)
816 {
817     int ret;
818 
819     ret = cds_check_len(cds, len);
820     if (ret <= 0) {
821         return ret;
822     }
823     if (!cds_ccw_addrs_ok(cds->cda, len, cds->flags & CDS_F_FMT)) {
824         return -EINVAL; /* channel program check */
825     }
826     if (op == CDS_OP_A) {
827         goto incr;
828     }
829     ret = address_space_rw(&address_space_memory, cds->cda,
830                            MEMTXATTRS_UNSPECIFIED, buff, len, op);
831     if (ret != MEMTX_OK) {
832         cds->flags |= CDS_F_STREAM_BROKEN;
833         return -EINVAL;
834     }
835 incr:
836     cds->at_byte += len;
837     cds->cda += len;
838     return 0;
839 }
840 
841 /* returns values between 1 and bsz, where bsz is a power of 2 */
842 static inline uint16_t ida_continuous_left(hwaddr cda, uint64_t bsz)
843 {
844     return bsz - (cda & (bsz - 1));
845 }
846 
847 static inline uint64_t ccw_ida_block_size(uint8_t flags)
848 {
849     if ((flags & CDS_F_C64) && !(flags & CDS_F_I2K)) {
850         return 1ULL << 12;
851     }
852     return 1ULL << 11;
853 }
854 
855 static inline int ida_read_next_idaw(CcwDataStream *cds)
856 {
857     union {uint64_t fmt2; uint32_t fmt1; } idaw;
858     int ret;
859     hwaddr idaw_addr;
860     bool idaw_fmt2 = cds->flags & CDS_F_C64;
861     bool ccw_fmt1 = cds->flags & CDS_F_FMT;
862 
863     if (idaw_fmt2) {
864         idaw_addr = cds->cda_orig + sizeof(idaw.fmt2) * cds->at_idaw;
865         if (idaw_addr & 0x07 || !cds_ccw_addrs_ok(idaw_addr, 0, ccw_fmt1)) {
866             return -EINVAL; /* channel program check */
867         }
868         ret = address_space_rw(&address_space_memory, idaw_addr,
869                                MEMTXATTRS_UNSPECIFIED, (void *) &idaw.fmt2,
870                                sizeof(idaw.fmt2), false);
871         cds->cda = be64_to_cpu(idaw.fmt2);
872     } else {
873         idaw_addr = cds->cda_orig + sizeof(idaw.fmt1) * cds->at_idaw;
874         if (idaw_addr & 0x03 || !cds_ccw_addrs_ok(idaw_addr, 0, ccw_fmt1)) {
875             return -EINVAL; /* channel program check */
876         }
877         ret = address_space_rw(&address_space_memory, idaw_addr,
878                                MEMTXATTRS_UNSPECIFIED, (void *) &idaw.fmt1,
879                                sizeof(idaw.fmt1), false);
880         cds->cda = be64_to_cpu(idaw.fmt1);
881         if (cds->cda & 0x80000000) {
882             return -EINVAL; /* channel program check */
883         }
884     }
885     ++(cds->at_idaw);
886     if (ret != MEMTX_OK) {
887         /* assume inaccessible address */
888         return -EINVAL; /* channel program check */
889     }
890     return 0;
891 }
892 
893 static int ccw_dstream_rw_ida(CcwDataStream *cds, void *buff, int len,
894                               CcwDataStreamOp op)
895 {
896     uint64_t bsz = ccw_ida_block_size(cds->flags);
897     int ret = 0;
898     uint16_t cont_left, iter_len;
899 
900     ret = cds_check_len(cds, len);
901     if (ret <= 0) {
902         return ret;
903     }
904     if (!cds->at_idaw) {
905         /* read first idaw */
906         ret = ida_read_next_idaw(cds);
907         if (ret) {
908             goto err;
909         }
910         cont_left = ida_continuous_left(cds->cda, bsz);
911     } else {
912         cont_left = ida_continuous_left(cds->cda, bsz);
913         if (cont_left == bsz) {
914             ret = ida_read_next_idaw(cds);
915             if (ret) {
916                 goto err;
917             }
918             if (cds->cda & (bsz - 1)) {
919                 ret = -EINVAL; /* channel program check */
920                 goto err;
921             }
922         }
923     }
924     do {
925         iter_len = MIN(len, cont_left);
926         if (op != CDS_OP_A) {
927             ret = address_space_rw(&address_space_memory, cds->cda,
928                                    MEMTXATTRS_UNSPECIFIED, buff, iter_len, op);
929             if (ret != MEMTX_OK) {
930                 /* assume inaccessible address */
931                 ret = -EINVAL; /* channel program check */
932                 goto err;
933             }
934         }
935         cds->at_byte += iter_len;
936         cds->cda += iter_len;
937         len -= iter_len;
938         if (!len) {
939             break;
940         }
941         ret = ida_read_next_idaw(cds);
942         if (ret) {
943             goto err;
944         }
945         cont_left = bsz;
946     } while (true);
947     return ret;
948 err:
949     cds->flags |= CDS_F_STREAM_BROKEN;
950     return ret;
951 }
952 
953 void ccw_dstream_init(CcwDataStream *cds, CCW1 const *ccw, ORB const *orb)
954 {
955     /*
956      * We don't support MIDA (an optional facility) yet and we
957      * catch this earlier. Just for expressing the precondition.
958      */
959     g_assert(!(orb->ctrl1 & ORB_CTRL1_MASK_MIDAW));
960     cds->flags = (orb->ctrl0 & ORB_CTRL0_MASK_I2K ? CDS_F_I2K : 0) |
961                  (orb->ctrl0 & ORB_CTRL0_MASK_C64 ? CDS_F_C64 : 0) |
962                  (orb->ctrl0 & ORB_CTRL0_MASK_FMT ? CDS_F_FMT : 0) |
963                  (ccw->flags & CCW_FLAG_IDA ? CDS_F_IDA : 0);
964 
965     cds->count = ccw->count;
966     cds->cda_orig = ccw->cda;
967     ccw_dstream_rewind(cds);
968     if (!(cds->flags & CDS_F_IDA)) {
969         cds->op_handler = ccw_dstream_rw_noflags;
970     } else {
971         cds->op_handler = ccw_dstream_rw_ida;
972     }
973 }
974 
975 static int css_interpret_ccw(SubchDev *sch, hwaddr ccw_addr,
976                              bool suspend_allowed)
977 {
978     int ret;
979     bool check_len;
980     int len;
981     CCW1 ccw;
982 
983     if (!ccw_addr) {
984         return -EINVAL; /* channel-program check */
985     }
986     /* Check doubleword aligned and 31 or 24 (fmt 0) bit addressable. */
987     if (ccw_addr & (sch->ccw_fmt_1 ? 0x80000007 : 0xff000007)) {
988         return -EINVAL;
989     }
990 
991     /* Translate everything to format-1 ccws - the information is the same. */
992     ccw = copy_ccw_from_guest(ccw_addr, sch->ccw_fmt_1);
993 
994     /* Check for invalid command codes. */
995     if ((ccw.cmd_code & 0x0f) == 0) {
996         return -EINVAL;
997     }
998     if (((ccw.cmd_code & 0x0f) == CCW_CMD_TIC) &&
999         ((ccw.cmd_code & 0xf0) != 0)) {
1000         return -EINVAL;
1001     }
1002     if (!sch->ccw_fmt_1 && (ccw.count == 0) &&
1003         (ccw.cmd_code != CCW_CMD_TIC)) {
1004         return -EINVAL;
1005     }
1006 
1007     /* We don't support MIDA. */
1008     if (ccw.flags & CCW_FLAG_MIDA) {
1009         return -EINVAL;
1010     }
1011 
1012     if (ccw.flags & CCW_FLAG_SUSPEND) {
1013         return suspend_allowed ? -EINPROGRESS : -EINVAL;
1014     }
1015 
1016     check_len = !((ccw.flags & CCW_FLAG_SLI) && !(ccw.flags & CCW_FLAG_DC));
1017 
1018     if (!ccw.cda) {
1019         if (sch->ccw_no_data_cnt == 255) {
1020             return -EINVAL;
1021         }
1022         sch->ccw_no_data_cnt++;
1023     }
1024 
1025     /* Look at the command. */
1026     ccw_dstream_init(&sch->cds, &ccw, &(sch->orb));
1027     switch (ccw.cmd_code) {
1028     case CCW_CMD_NOOP:
1029         /* Nothing to do. */
1030         ret = 0;
1031         break;
1032     case CCW_CMD_BASIC_SENSE:
1033         if (check_len) {
1034             if (ccw.count != sizeof(sch->sense_data)) {
1035                 ret = -EINVAL;
1036                 break;
1037             }
1038         }
1039         len = MIN(ccw.count, sizeof(sch->sense_data));
1040         ccw_dstream_write_buf(&sch->cds, sch->sense_data, len);
1041         sch->curr_status.scsw.count = ccw_dstream_residual_count(&sch->cds);
1042         memset(sch->sense_data, 0, sizeof(sch->sense_data));
1043         ret = 0;
1044         break;
1045     case CCW_CMD_SENSE_ID:
1046     {
1047         SenseId sense_id;
1048 
1049         copy_sense_id_to_guest(&sense_id, &sch->id);
1050         /* Sense ID information is device specific. */
1051         if (check_len) {
1052             if (ccw.count != sizeof(sense_id)) {
1053                 ret = -EINVAL;
1054                 break;
1055             }
1056         }
1057         len = MIN(ccw.count, sizeof(sense_id));
1058         /*
1059          * Only indicate 0xff in the first sense byte if we actually
1060          * have enough place to store at least bytes 0-3.
1061          */
1062         if (len >= 4) {
1063             sense_id.reserved = 0xff;
1064         } else {
1065             sense_id.reserved = 0;
1066         }
1067         ccw_dstream_write_buf(&sch->cds, &sense_id, len);
1068         sch->curr_status.scsw.count = ccw_dstream_residual_count(&sch->cds);
1069         ret = 0;
1070         break;
1071     }
1072     case CCW_CMD_TIC:
1073         if (sch->last_cmd_valid && (sch->last_cmd.cmd_code == CCW_CMD_TIC)) {
1074             ret = -EINVAL;
1075             break;
1076         }
1077         if (ccw.flags || ccw.count) {
1078             /* We have already sanitized these if converted from fmt 0. */
1079             ret = -EINVAL;
1080             break;
1081         }
1082         sch->channel_prog = ccw.cda;
1083         ret = -EAGAIN;
1084         break;
1085     default:
1086         if (sch->ccw_cb) {
1087             /* Handle device specific commands. */
1088             ret = sch->ccw_cb(sch, ccw);
1089         } else {
1090             ret = -ENOSYS;
1091         }
1092         break;
1093     }
1094     sch->last_cmd = ccw;
1095     sch->last_cmd_valid = true;
1096     if (ret == 0) {
1097         if (ccw.flags & CCW_FLAG_CC) {
1098             sch->channel_prog += 8;
1099             ret = -EAGAIN;
1100         }
1101     }
1102 
1103     return ret;
1104 }
1105 
1106 static void sch_handle_start_func_virtual(SubchDev *sch)
1107 {
1108 
1109     PMCW *p = &sch->curr_status.pmcw;
1110     SCSW *s = &sch->curr_status.scsw;
1111     int path;
1112     int ret;
1113     bool suspend_allowed;
1114 
1115     /* Path management: In our simple css, we always choose the only path. */
1116     path = 0x80;
1117 
1118     if (!(s->ctrl & SCSW_ACTL_SUSP)) {
1119         /* Start Function triggered via ssch, i.e. we have an ORB */
1120         ORB *orb = &sch->orb;
1121         s->cstat = 0;
1122         s->dstat = 0;
1123         /* Look at the orb and try to execute the channel program. */
1124         p->intparm = orb->intparm;
1125         if (!(orb->lpm & path)) {
1126             /* Generate a deferred cc 3 condition. */
1127             s->flags |= SCSW_FLAGS_MASK_CC;
1128             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
1129             s->ctrl |= (SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND);
1130             return;
1131         }
1132         sch->ccw_fmt_1 = !!(orb->ctrl0 & ORB_CTRL0_MASK_FMT);
1133         s->flags |= (sch->ccw_fmt_1) ? SCSW_FLAGS_MASK_FMT : 0;
1134         sch->ccw_no_data_cnt = 0;
1135         suspend_allowed = !!(orb->ctrl0 & ORB_CTRL0_MASK_SPND);
1136     } else {
1137         /* Start Function resumed via rsch */
1138         s->ctrl &= ~(SCSW_ACTL_SUSP | SCSW_ACTL_RESUME_PEND);
1139         /* The channel program had been suspended before. */
1140         suspend_allowed = true;
1141     }
1142     sch->last_cmd_valid = false;
1143     do {
1144         ret = css_interpret_ccw(sch, sch->channel_prog, suspend_allowed);
1145         switch (ret) {
1146         case -EAGAIN:
1147             /* ccw chain, continue processing */
1148             break;
1149         case 0:
1150             /* success */
1151             s->ctrl &= ~SCSW_ACTL_START_PEND;
1152             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
1153             s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
1154                     SCSW_STCTL_STATUS_PEND;
1155             s->dstat = SCSW_DSTAT_CHANNEL_END | SCSW_DSTAT_DEVICE_END;
1156             s->cpa = sch->channel_prog + 8;
1157             break;
1158         case -EIO:
1159             /* I/O errors, status depends on specific devices */
1160             break;
1161         case -ENOSYS:
1162             /* unsupported command, generate unit check (command reject) */
1163             s->ctrl &= ~SCSW_ACTL_START_PEND;
1164             s->dstat = SCSW_DSTAT_UNIT_CHECK;
1165             /* Set sense bit 0 in ecw0. */
1166             sch->sense_data[0] = 0x80;
1167             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
1168             s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
1169                     SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
1170             s->cpa = sch->channel_prog + 8;
1171             break;
1172         case -EINPROGRESS:
1173             /* channel program has been suspended */
1174             s->ctrl &= ~SCSW_ACTL_START_PEND;
1175             s->ctrl |= SCSW_ACTL_SUSP;
1176             break;
1177         default:
1178             /* error, generate channel program check */
1179             s->ctrl &= ~SCSW_ACTL_START_PEND;
1180             s->cstat = SCSW_CSTAT_PROG_CHECK;
1181             s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
1182             s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
1183                     SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
1184             s->cpa = sch->channel_prog + 8;
1185             break;
1186         }
1187     } while (ret == -EAGAIN);
1188 
1189 }
1190 
1191 static IOInstEnding sch_handle_start_func_passthrough(SubchDev *sch)
1192 {
1193 
1194     PMCW *p = &sch->curr_status.pmcw;
1195     SCSW *s = &sch->curr_status.scsw;
1196 
1197     ORB *orb = &sch->orb;
1198     if (!(s->ctrl & SCSW_ACTL_SUSP)) {
1199         assert(orb != NULL);
1200         p->intparm = orb->intparm;
1201     }
1202     return s390_ccw_cmd_request(sch);
1203 }
1204 
1205 /*
1206  * On real machines, this would run asynchronously to the main vcpus.
1207  * We might want to make some parts of the ssch handling (interpreting
1208  * read/writes) asynchronous later on if we start supporting more than
1209  * our current very simple devices.
1210  */
1211 IOInstEnding do_subchannel_work_virtual(SubchDev *sch)
1212 {
1213 
1214     SCSW *s = &sch->curr_status.scsw;
1215 
1216     if (s->ctrl & SCSW_FCTL_CLEAR_FUNC) {
1217         sch_handle_clear_func(sch);
1218     } else if (s->ctrl & SCSW_FCTL_HALT_FUNC) {
1219         sch_handle_halt_func(sch);
1220     } else if (s->ctrl & SCSW_FCTL_START_FUNC) {
1221         /* Triggered by both ssch and rsch. */
1222         sch_handle_start_func_virtual(sch);
1223     }
1224     css_inject_io_interrupt(sch);
1225     /* inst must succeed if this func is called */
1226     return IOINST_CC_EXPECTED;
1227 }
1228 
1229 IOInstEnding do_subchannel_work_passthrough(SubchDev *sch)
1230 {
1231     SCSW *s = &sch->curr_status.scsw;
1232 
1233     if (s->ctrl & SCSW_FCTL_CLEAR_FUNC) {
1234         /* TODO: Clear handling */
1235         sch_handle_clear_func(sch);
1236     } else if (s->ctrl & SCSW_FCTL_HALT_FUNC) {
1237         /* TODO: Halt handling */
1238         sch_handle_halt_func(sch);
1239     } else if (s->ctrl & SCSW_FCTL_START_FUNC) {
1240         return sch_handle_start_func_passthrough(sch);
1241     }
1242     return IOINST_CC_EXPECTED;
1243 }
1244 
1245 static IOInstEnding do_subchannel_work(SubchDev *sch)
1246 {
1247     if (!sch->do_subchannel_work) {
1248         return IOINST_CC_STATUS_PRESENT;
1249     }
1250     g_assert(sch->curr_status.scsw.ctrl & SCSW_CTRL_MASK_FCTL);
1251     return sch->do_subchannel_work(sch);
1252 }
1253 
1254 static void copy_pmcw_to_guest(PMCW *dest, const PMCW *src)
1255 {
1256     int i;
1257 
1258     dest->intparm = cpu_to_be32(src->intparm);
1259     dest->flags = cpu_to_be16(src->flags);
1260     dest->devno = cpu_to_be16(src->devno);
1261     dest->lpm = src->lpm;
1262     dest->pnom = src->pnom;
1263     dest->lpum = src->lpum;
1264     dest->pim = src->pim;
1265     dest->mbi = cpu_to_be16(src->mbi);
1266     dest->pom = src->pom;
1267     dest->pam = src->pam;
1268     for (i = 0; i < ARRAY_SIZE(dest->chpid); i++) {
1269         dest->chpid[i] = src->chpid[i];
1270     }
1271     dest->chars = cpu_to_be32(src->chars);
1272 }
1273 
1274 void copy_scsw_to_guest(SCSW *dest, const SCSW *src)
1275 {
1276     dest->flags = cpu_to_be16(src->flags);
1277     dest->ctrl = cpu_to_be16(src->ctrl);
1278     dest->cpa = cpu_to_be32(src->cpa);
1279     dest->dstat = src->dstat;
1280     dest->cstat = src->cstat;
1281     dest->count = cpu_to_be16(src->count);
1282 }
1283 
1284 static void copy_schib_to_guest(SCHIB *dest, const SCHIB *src)
1285 {
1286     int i;
1287 
1288     copy_pmcw_to_guest(&dest->pmcw, &src->pmcw);
1289     copy_scsw_to_guest(&dest->scsw, &src->scsw);
1290     dest->mba = cpu_to_be64(src->mba);
1291     for (i = 0; i < ARRAY_SIZE(dest->mda); i++) {
1292         dest->mda[i] = src->mda[i];
1293     }
1294 }
1295 
1296 int css_do_stsch(SubchDev *sch, SCHIB *schib)
1297 {
1298     /* Use current status. */
1299     copy_schib_to_guest(schib, &sch->curr_status);
1300     return 0;
1301 }
1302 
1303 static void copy_pmcw_from_guest(PMCW *dest, const PMCW *src)
1304 {
1305     int i;
1306 
1307     dest->intparm = be32_to_cpu(src->intparm);
1308     dest->flags = be16_to_cpu(src->flags);
1309     dest->devno = be16_to_cpu(src->devno);
1310     dest->lpm = src->lpm;
1311     dest->pnom = src->pnom;
1312     dest->lpum = src->lpum;
1313     dest->pim = src->pim;
1314     dest->mbi = be16_to_cpu(src->mbi);
1315     dest->pom = src->pom;
1316     dest->pam = src->pam;
1317     for (i = 0; i < ARRAY_SIZE(dest->chpid); i++) {
1318         dest->chpid[i] = src->chpid[i];
1319     }
1320     dest->chars = be32_to_cpu(src->chars);
1321 }
1322 
1323 static void copy_scsw_from_guest(SCSW *dest, const SCSW *src)
1324 {
1325     dest->flags = be16_to_cpu(src->flags);
1326     dest->ctrl = be16_to_cpu(src->ctrl);
1327     dest->cpa = be32_to_cpu(src->cpa);
1328     dest->dstat = src->dstat;
1329     dest->cstat = src->cstat;
1330     dest->count = be16_to_cpu(src->count);
1331 }
1332 
1333 static void copy_schib_from_guest(SCHIB *dest, const SCHIB *src)
1334 {
1335     int i;
1336 
1337     copy_pmcw_from_guest(&dest->pmcw, &src->pmcw);
1338     copy_scsw_from_guest(&dest->scsw, &src->scsw);
1339     dest->mba = be64_to_cpu(src->mba);
1340     for (i = 0; i < ARRAY_SIZE(dest->mda); i++) {
1341         dest->mda[i] = src->mda[i];
1342     }
1343 }
1344 
1345 IOInstEnding css_do_msch(SubchDev *sch, const SCHIB *orig_schib)
1346 {
1347     SCSW *s = &sch->curr_status.scsw;
1348     PMCW *p = &sch->curr_status.pmcw;
1349     uint16_t oldflags;
1350     SCHIB schib;
1351 
1352     if (!(sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_DNV)) {
1353         return IOINST_CC_EXPECTED;
1354     }
1355 
1356     if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
1357         return IOINST_CC_STATUS_PRESENT;
1358     }
1359 
1360     if (s->ctrl &
1361         (SCSW_FCTL_START_FUNC|SCSW_FCTL_HALT_FUNC|SCSW_FCTL_CLEAR_FUNC)) {
1362         return IOINST_CC_BUSY;
1363     }
1364 
1365     copy_schib_from_guest(&schib, orig_schib);
1366     /* Only update the program-modifiable fields. */
1367     p->intparm = schib.pmcw.intparm;
1368     oldflags = p->flags;
1369     p->flags &= ~(PMCW_FLAGS_MASK_ISC | PMCW_FLAGS_MASK_ENA |
1370                   PMCW_FLAGS_MASK_LM | PMCW_FLAGS_MASK_MME |
1371                   PMCW_FLAGS_MASK_MP);
1372     p->flags |= schib.pmcw.flags &
1373             (PMCW_FLAGS_MASK_ISC | PMCW_FLAGS_MASK_ENA |
1374              PMCW_FLAGS_MASK_LM | PMCW_FLAGS_MASK_MME |
1375              PMCW_FLAGS_MASK_MP);
1376     p->lpm = schib.pmcw.lpm;
1377     p->mbi = schib.pmcw.mbi;
1378     p->pom = schib.pmcw.pom;
1379     p->chars &= ~(PMCW_CHARS_MASK_MBFC | PMCW_CHARS_MASK_CSENSE);
1380     p->chars |= schib.pmcw.chars &
1381             (PMCW_CHARS_MASK_MBFC | PMCW_CHARS_MASK_CSENSE);
1382     sch->curr_status.mba = schib.mba;
1383 
1384     /* Has the channel been disabled? */
1385     if (sch->disable_cb && (oldflags & PMCW_FLAGS_MASK_ENA) != 0
1386         && (p->flags & PMCW_FLAGS_MASK_ENA) == 0) {
1387         sch->disable_cb(sch);
1388     }
1389     return IOINST_CC_EXPECTED;
1390 }
1391 
1392 IOInstEnding css_do_xsch(SubchDev *sch)
1393 {
1394     SCSW *s = &sch->curr_status.scsw;
1395     PMCW *p = &sch->curr_status.pmcw;
1396 
1397     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1398         return IOINST_CC_NOT_OPERATIONAL;
1399     }
1400 
1401     if (s->ctrl & SCSW_CTRL_MASK_STCTL) {
1402         return IOINST_CC_STATUS_PRESENT;
1403     }
1404 
1405     if (!(s->ctrl & SCSW_CTRL_MASK_FCTL) ||
1406         ((s->ctrl & SCSW_CTRL_MASK_FCTL) != SCSW_FCTL_START_FUNC) ||
1407         (!(s->ctrl &
1408            (SCSW_ACTL_RESUME_PEND | SCSW_ACTL_START_PEND | SCSW_ACTL_SUSP))) ||
1409         (s->ctrl & SCSW_ACTL_SUBCH_ACTIVE)) {
1410         return IOINST_CC_BUSY;
1411     }
1412 
1413     /* Cancel the current operation. */
1414     s->ctrl &= ~(SCSW_FCTL_START_FUNC |
1415                  SCSW_ACTL_RESUME_PEND |
1416                  SCSW_ACTL_START_PEND |
1417                  SCSW_ACTL_SUSP);
1418     sch->channel_prog = 0x0;
1419     sch->last_cmd_valid = false;
1420     s->dstat = 0;
1421     s->cstat = 0;
1422     return IOINST_CC_EXPECTED;
1423 }
1424 
1425 IOInstEnding css_do_csch(SubchDev *sch)
1426 {
1427     SCSW *s = &sch->curr_status.scsw;
1428     PMCW *p = &sch->curr_status.pmcw;
1429 
1430     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1431         return IOINST_CC_NOT_OPERATIONAL;
1432     }
1433 
1434     /* Trigger the clear function. */
1435     s->ctrl &= ~(SCSW_CTRL_MASK_FCTL | SCSW_CTRL_MASK_ACTL);
1436     s->ctrl |= SCSW_FCTL_CLEAR_FUNC | SCSW_ACTL_CLEAR_PEND;
1437 
1438     return do_subchannel_work(sch);
1439 }
1440 
1441 IOInstEnding css_do_hsch(SubchDev *sch)
1442 {
1443     SCSW *s = &sch->curr_status.scsw;
1444     PMCW *p = &sch->curr_status.pmcw;
1445 
1446     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1447         return IOINST_CC_NOT_OPERATIONAL;
1448     }
1449 
1450     if (((s->ctrl & SCSW_CTRL_MASK_STCTL) == SCSW_STCTL_STATUS_PEND) ||
1451         (s->ctrl & (SCSW_STCTL_PRIMARY |
1452                     SCSW_STCTL_SECONDARY |
1453                     SCSW_STCTL_ALERT))) {
1454         return IOINST_CC_STATUS_PRESENT;
1455     }
1456 
1457     if (s->ctrl & (SCSW_FCTL_HALT_FUNC | SCSW_FCTL_CLEAR_FUNC)) {
1458         return IOINST_CC_BUSY;
1459     }
1460 
1461     /* Trigger the halt function. */
1462     s->ctrl |= SCSW_FCTL_HALT_FUNC;
1463     s->ctrl &= ~SCSW_FCTL_START_FUNC;
1464     if (((s->ctrl & SCSW_CTRL_MASK_ACTL) ==
1465          (SCSW_ACTL_SUBCH_ACTIVE | SCSW_ACTL_DEVICE_ACTIVE)) &&
1466         ((s->ctrl & SCSW_CTRL_MASK_STCTL) == SCSW_STCTL_INTERMEDIATE)) {
1467         s->ctrl &= ~SCSW_STCTL_STATUS_PEND;
1468     }
1469     s->ctrl |= SCSW_ACTL_HALT_PEND;
1470 
1471     return do_subchannel_work(sch);
1472 }
1473 
1474 static void css_update_chnmon(SubchDev *sch)
1475 {
1476     if (!(sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_MME)) {
1477         /* Not active. */
1478         return;
1479     }
1480     /* The counter is conveniently located at the beginning of the struct. */
1481     if (sch->curr_status.pmcw.chars & PMCW_CHARS_MASK_MBFC) {
1482         /* Format 1, per-subchannel area. */
1483         uint32_t count;
1484 
1485         count = address_space_ldl(&address_space_memory,
1486                                   sch->curr_status.mba,
1487                                   MEMTXATTRS_UNSPECIFIED,
1488                                   NULL);
1489         count++;
1490         address_space_stl(&address_space_memory, sch->curr_status.mba, count,
1491                           MEMTXATTRS_UNSPECIFIED, NULL);
1492     } else {
1493         /* Format 0, global area. */
1494         uint32_t offset;
1495         uint16_t count;
1496 
1497         offset = sch->curr_status.pmcw.mbi << 5;
1498         count = address_space_lduw(&address_space_memory,
1499                                    channel_subsys.chnmon_area + offset,
1500                                    MEMTXATTRS_UNSPECIFIED,
1501                                    NULL);
1502         count++;
1503         address_space_stw(&address_space_memory,
1504                           channel_subsys.chnmon_area + offset, count,
1505                           MEMTXATTRS_UNSPECIFIED, NULL);
1506     }
1507 }
1508 
1509 IOInstEnding css_do_ssch(SubchDev *sch, ORB *orb)
1510 {
1511     SCSW *s = &sch->curr_status.scsw;
1512     PMCW *p = &sch->curr_status.pmcw;
1513 
1514     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1515         return IOINST_CC_NOT_OPERATIONAL;
1516     }
1517 
1518     if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
1519         return IOINST_CC_STATUS_PRESENT;
1520     }
1521 
1522     if (s->ctrl & (SCSW_FCTL_START_FUNC |
1523                    SCSW_FCTL_HALT_FUNC |
1524                    SCSW_FCTL_CLEAR_FUNC)) {
1525         return IOINST_CC_BUSY;
1526     }
1527 
1528     /* If monitoring is active, update counter. */
1529     if (channel_subsys.chnmon_active) {
1530         css_update_chnmon(sch);
1531     }
1532     sch->orb = *orb;
1533     sch->channel_prog = orb->cpa;
1534     /* Trigger the start function. */
1535     s->ctrl |= (SCSW_FCTL_START_FUNC | SCSW_ACTL_START_PEND);
1536     s->flags &= ~SCSW_FLAGS_MASK_PNO;
1537 
1538     return do_subchannel_work(sch);
1539 }
1540 
1541 static void copy_irb_to_guest(IRB *dest, const IRB *src, PMCW *pmcw,
1542                               int *irb_len)
1543 {
1544     int i;
1545     uint16_t stctl = src->scsw.ctrl & SCSW_CTRL_MASK_STCTL;
1546     uint16_t actl = src->scsw.ctrl & SCSW_CTRL_MASK_ACTL;
1547 
1548     copy_scsw_to_guest(&dest->scsw, &src->scsw);
1549 
1550     for (i = 0; i < ARRAY_SIZE(dest->esw); i++) {
1551         dest->esw[i] = cpu_to_be32(src->esw[i]);
1552     }
1553     for (i = 0; i < ARRAY_SIZE(dest->ecw); i++) {
1554         dest->ecw[i] = cpu_to_be32(src->ecw[i]);
1555     }
1556     *irb_len = sizeof(*dest) - sizeof(dest->emw);
1557 
1558     /* extended measurements enabled? */
1559     if ((src->scsw.flags & SCSW_FLAGS_MASK_ESWF) ||
1560         !(pmcw->flags & PMCW_FLAGS_MASK_TF) ||
1561         !(pmcw->chars & PMCW_CHARS_MASK_XMWME)) {
1562         return;
1563     }
1564     /* extended measurements pending? */
1565     if (!(stctl & SCSW_STCTL_STATUS_PEND)) {
1566         return;
1567     }
1568     if ((stctl & SCSW_STCTL_PRIMARY) ||
1569         (stctl == SCSW_STCTL_SECONDARY) ||
1570         ((stctl & SCSW_STCTL_INTERMEDIATE) && (actl & SCSW_ACTL_SUSP))) {
1571         for (i = 0; i < ARRAY_SIZE(dest->emw); i++) {
1572             dest->emw[i] = cpu_to_be32(src->emw[i]);
1573         }
1574     }
1575     *irb_len = sizeof(*dest);
1576 }
1577 
1578 int css_do_tsch_get_irb(SubchDev *sch, IRB *target_irb, int *irb_len)
1579 {
1580     SCSW *s = &sch->curr_status.scsw;
1581     PMCW *p = &sch->curr_status.pmcw;
1582     uint16_t stctl;
1583     IRB irb;
1584 
1585     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1586         return 3;
1587     }
1588 
1589     stctl = s->ctrl & SCSW_CTRL_MASK_STCTL;
1590 
1591     /* Prepare the irb for the guest. */
1592     memset(&irb, 0, sizeof(IRB));
1593 
1594     /* Copy scsw from current status. */
1595     memcpy(&irb.scsw, s, sizeof(SCSW));
1596     if (stctl & SCSW_STCTL_STATUS_PEND) {
1597         if (s->cstat & (SCSW_CSTAT_DATA_CHECK |
1598                         SCSW_CSTAT_CHN_CTRL_CHK |
1599                         SCSW_CSTAT_INTF_CTRL_CHK)) {
1600             irb.scsw.flags |= SCSW_FLAGS_MASK_ESWF;
1601             irb.esw[0] = 0x04804000;
1602         } else {
1603             irb.esw[0] = 0x00800000;
1604         }
1605         /* If a unit check is pending, copy sense data. */
1606         if ((s->dstat & SCSW_DSTAT_UNIT_CHECK) &&
1607             (p->chars & PMCW_CHARS_MASK_CSENSE)) {
1608             int i;
1609 
1610             irb.scsw.flags |= SCSW_FLAGS_MASK_ESWF | SCSW_FLAGS_MASK_ECTL;
1611             /* Attention: sense_data is already BE! */
1612             memcpy(irb.ecw, sch->sense_data, sizeof(sch->sense_data));
1613             for (i = 0; i < ARRAY_SIZE(irb.ecw); i++) {
1614                 irb.ecw[i] = be32_to_cpu(irb.ecw[i]);
1615             }
1616             irb.esw[1] = 0x01000000 | (sizeof(sch->sense_data) << 8);
1617         }
1618     }
1619     /* Store the irb to the guest. */
1620     copy_irb_to_guest(target_irb, &irb, p, irb_len);
1621 
1622     return ((stctl & SCSW_STCTL_STATUS_PEND) == 0);
1623 }
1624 
1625 void css_do_tsch_update_subch(SubchDev *sch)
1626 {
1627     SCSW *s = &sch->curr_status.scsw;
1628     PMCW *p = &sch->curr_status.pmcw;
1629     uint16_t stctl;
1630     uint16_t fctl;
1631     uint16_t actl;
1632 
1633     stctl = s->ctrl & SCSW_CTRL_MASK_STCTL;
1634     fctl = s->ctrl & SCSW_CTRL_MASK_FCTL;
1635     actl = s->ctrl & SCSW_CTRL_MASK_ACTL;
1636 
1637     /* Clear conditions on subchannel, if applicable. */
1638     if (stctl & SCSW_STCTL_STATUS_PEND) {
1639         s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
1640         if ((stctl != (SCSW_STCTL_INTERMEDIATE | SCSW_STCTL_STATUS_PEND)) ||
1641             ((fctl & SCSW_FCTL_HALT_FUNC) &&
1642              (actl & SCSW_ACTL_SUSP))) {
1643             s->ctrl &= ~SCSW_CTRL_MASK_FCTL;
1644         }
1645         if (stctl != (SCSW_STCTL_INTERMEDIATE | SCSW_STCTL_STATUS_PEND)) {
1646             s->flags &= ~SCSW_FLAGS_MASK_PNO;
1647             s->ctrl &= ~(SCSW_ACTL_RESUME_PEND |
1648                          SCSW_ACTL_START_PEND |
1649                          SCSW_ACTL_HALT_PEND |
1650                          SCSW_ACTL_CLEAR_PEND |
1651                          SCSW_ACTL_SUSP);
1652         } else {
1653             if ((actl & SCSW_ACTL_SUSP) &&
1654                 (fctl & SCSW_FCTL_START_FUNC)) {
1655                 s->flags &= ~SCSW_FLAGS_MASK_PNO;
1656                 if (fctl & SCSW_FCTL_HALT_FUNC) {
1657                     s->ctrl &= ~(SCSW_ACTL_RESUME_PEND |
1658                                  SCSW_ACTL_START_PEND |
1659                                  SCSW_ACTL_HALT_PEND |
1660                                  SCSW_ACTL_CLEAR_PEND |
1661                                  SCSW_ACTL_SUSP);
1662                 } else {
1663                     s->ctrl &= ~SCSW_ACTL_RESUME_PEND;
1664                 }
1665             }
1666         }
1667         /* Clear pending sense data. */
1668         if (p->chars & PMCW_CHARS_MASK_CSENSE) {
1669             memset(sch->sense_data, 0 , sizeof(sch->sense_data));
1670         }
1671     }
1672 }
1673 
1674 static void copy_crw_to_guest(CRW *dest, const CRW *src)
1675 {
1676     dest->flags = cpu_to_be16(src->flags);
1677     dest->rsid = cpu_to_be16(src->rsid);
1678 }
1679 
1680 int css_do_stcrw(CRW *crw)
1681 {
1682     CrwContainer *crw_cont;
1683     int ret;
1684 
1685     crw_cont = QTAILQ_FIRST(&channel_subsys.pending_crws);
1686     if (crw_cont) {
1687         QTAILQ_REMOVE(&channel_subsys.pending_crws, crw_cont, sibling);
1688         copy_crw_to_guest(crw, &crw_cont->crw);
1689         g_free(crw_cont);
1690         ret = 0;
1691     } else {
1692         /* List was empty, turn crw machine checks on again. */
1693         memset(crw, 0, sizeof(*crw));
1694         channel_subsys.do_crw_mchk = true;
1695         ret = 1;
1696     }
1697 
1698     return ret;
1699 }
1700 
1701 static void copy_crw_from_guest(CRW *dest, const CRW *src)
1702 {
1703     dest->flags = be16_to_cpu(src->flags);
1704     dest->rsid = be16_to_cpu(src->rsid);
1705 }
1706 
1707 void css_undo_stcrw(CRW *crw)
1708 {
1709     CrwContainer *crw_cont;
1710 
1711     crw_cont = g_try_new0(CrwContainer, 1);
1712     if (!crw_cont) {
1713         channel_subsys.crws_lost = true;
1714         return;
1715     }
1716     copy_crw_from_guest(&crw_cont->crw, crw);
1717 
1718     QTAILQ_INSERT_HEAD(&channel_subsys.pending_crws, crw_cont, sibling);
1719 }
1720 
1721 int css_collect_chp_desc(int m, uint8_t cssid, uint8_t f_chpid, uint8_t l_chpid,
1722                          int rfmt, void *buf)
1723 {
1724     int i, desc_size;
1725     uint32_t words[8];
1726     uint32_t chpid_type_word;
1727     CssImage *css;
1728 
1729     if (!m && !cssid) {
1730         css = channel_subsys.css[channel_subsys.default_cssid];
1731     } else {
1732         css = channel_subsys.css[cssid];
1733     }
1734     if (!css) {
1735         return 0;
1736     }
1737     desc_size = 0;
1738     for (i = f_chpid; i <= l_chpid; i++) {
1739         if (css->chpids[i].in_use) {
1740             chpid_type_word = 0x80000000 | (css->chpids[i].type << 8) | i;
1741             if (rfmt == 0) {
1742                 words[0] = cpu_to_be32(chpid_type_word);
1743                 words[1] = 0;
1744                 memcpy(buf + desc_size, words, 8);
1745                 desc_size += 8;
1746             } else if (rfmt == 1) {
1747                 words[0] = cpu_to_be32(chpid_type_word);
1748                 words[1] = 0;
1749                 words[2] = 0;
1750                 words[3] = 0;
1751                 words[4] = 0;
1752                 words[5] = 0;
1753                 words[6] = 0;
1754                 words[7] = 0;
1755                 memcpy(buf + desc_size, words, 32);
1756                 desc_size += 32;
1757             }
1758         }
1759     }
1760     return desc_size;
1761 }
1762 
1763 void css_do_schm(uint8_t mbk, int update, int dct, uint64_t mbo)
1764 {
1765     /* dct is currently ignored (not really meaningful for our devices) */
1766     /* TODO: Don't ignore mbk. */
1767     if (update && !channel_subsys.chnmon_active) {
1768         /* Enable measuring. */
1769         channel_subsys.chnmon_area = mbo;
1770         channel_subsys.chnmon_active = true;
1771     }
1772     if (!update && channel_subsys.chnmon_active) {
1773         /* Disable measuring. */
1774         channel_subsys.chnmon_area = 0;
1775         channel_subsys.chnmon_active = false;
1776     }
1777 }
1778 
1779 IOInstEnding css_do_rsch(SubchDev *sch)
1780 {
1781     SCSW *s = &sch->curr_status.scsw;
1782     PMCW *p = &sch->curr_status.pmcw;
1783 
1784     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1785         return IOINST_CC_NOT_OPERATIONAL;
1786     }
1787 
1788     if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
1789         return IOINST_CC_STATUS_PRESENT;
1790     }
1791 
1792     if (((s->ctrl & SCSW_CTRL_MASK_FCTL) != SCSW_FCTL_START_FUNC) ||
1793         (s->ctrl & SCSW_ACTL_RESUME_PEND) ||
1794         (!(s->ctrl & SCSW_ACTL_SUSP))) {
1795         return IOINST_CC_BUSY;
1796     }
1797 
1798     /* If monitoring is active, update counter. */
1799     if (channel_subsys.chnmon_active) {
1800         css_update_chnmon(sch);
1801     }
1802 
1803     s->ctrl |= SCSW_ACTL_RESUME_PEND;
1804     return do_subchannel_work(sch);
1805 }
1806 
1807 int css_do_rchp(uint8_t cssid, uint8_t chpid)
1808 {
1809     uint8_t real_cssid;
1810 
1811     if (cssid > channel_subsys.max_cssid) {
1812         return -EINVAL;
1813     }
1814     if (channel_subsys.max_cssid == 0) {
1815         real_cssid = channel_subsys.default_cssid;
1816     } else {
1817         real_cssid = cssid;
1818     }
1819     if (!channel_subsys.css[real_cssid]) {
1820         return -EINVAL;
1821     }
1822 
1823     if (!channel_subsys.css[real_cssid]->chpids[chpid].in_use) {
1824         return -ENODEV;
1825     }
1826 
1827     if (!channel_subsys.css[real_cssid]->chpids[chpid].is_virtual) {
1828         fprintf(stderr,
1829                 "rchp unsupported for non-virtual chpid %x.%02x!\n",
1830                 real_cssid, chpid);
1831         return -ENODEV;
1832     }
1833 
1834     /* We don't really use a channel path, so we're done here. */
1835     css_queue_crw(CRW_RSC_CHP, CRW_ERC_INIT, 1,
1836                   channel_subsys.max_cssid > 0 ? 1 : 0, chpid);
1837     if (channel_subsys.max_cssid > 0) {
1838         css_queue_crw(CRW_RSC_CHP, CRW_ERC_INIT, 1, 0, real_cssid << 8);
1839     }
1840     return 0;
1841 }
1842 
1843 bool css_schid_final(int m, uint8_t cssid, uint8_t ssid, uint16_t schid)
1844 {
1845     SubchSet *set;
1846     uint8_t real_cssid;
1847 
1848     real_cssid = (!m && (cssid == 0)) ? channel_subsys.default_cssid : cssid;
1849     if (ssid > MAX_SSID ||
1850         !channel_subsys.css[real_cssid] ||
1851         !channel_subsys.css[real_cssid]->sch_set[ssid]) {
1852         return true;
1853     }
1854     set = channel_subsys.css[real_cssid]->sch_set[ssid];
1855     return schid > find_last_bit(set->schids_used,
1856                                  (MAX_SCHID + 1) / sizeof(unsigned long));
1857 }
1858 
1859 unsigned int css_find_free_chpid(uint8_t cssid)
1860 {
1861     CssImage *css = channel_subsys.css[cssid];
1862     unsigned int chpid;
1863 
1864     if (!css) {
1865         return MAX_CHPID + 1;
1866     }
1867 
1868     for (chpid = 0; chpid <= MAX_CHPID; chpid++) {
1869         /* skip reserved chpid */
1870         if (chpid == VIRTIO_CCW_CHPID) {
1871             continue;
1872         }
1873         if (!css->chpids[chpid].in_use) {
1874             return chpid;
1875         }
1876     }
1877     return MAX_CHPID + 1;
1878 }
1879 
1880 static int css_add_chpid(uint8_t cssid, uint8_t chpid, uint8_t type,
1881                          bool is_virt)
1882 {
1883     CssImage *css;
1884 
1885     trace_css_chpid_add(cssid, chpid, type);
1886     css = channel_subsys.css[cssid];
1887     if (!css) {
1888         return -EINVAL;
1889     }
1890     if (css->chpids[chpid].in_use) {
1891         return -EEXIST;
1892     }
1893     css->chpids[chpid].in_use = 1;
1894     css->chpids[chpid].type = type;
1895     css->chpids[chpid].is_virtual = is_virt;
1896 
1897     css_generate_chp_crws(cssid, chpid);
1898 
1899     return 0;
1900 }
1901 
1902 void css_sch_build_virtual_schib(SubchDev *sch, uint8_t chpid, uint8_t type)
1903 {
1904     PMCW *p = &sch->curr_status.pmcw;
1905     SCSW *s = &sch->curr_status.scsw;
1906     int i;
1907     CssImage *css = channel_subsys.css[sch->cssid];
1908 
1909     assert(css != NULL);
1910     memset(p, 0, sizeof(PMCW));
1911     p->flags |= PMCW_FLAGS_MASK_DNV;
1912     p->devno = sch->devno;
1913     /* single path */
1914     p->pim = 0x80;
1915     p->pom = 0xff;
1916     p->pam = 0x80;
1917     p->chpid[0] = chpid;
1918     if (!css->chpids[chpid].in_use) {
1919         css_add_chpid(sch->cssid, chpid, type, true);
1920     }
1921 
1922     memset(s, 0, sizeof(SCSW));
1923     sch->curr_status.mba = 0;
1924     for (i = 0; i < ARRAY_SIZE(sch->curr_status.mda); i++) {
1925         sch->curr_status.mda[i] = 0;
1926     }
1927 }
1928 
1929 SubchDev *css_find_subch(uint8_t m, uint8_t cssid, uint8_t ssid, uint16_t schid)
1930 {
1931     uint8_t real_cssid;
1932 
1933     real_cssid = (!m && (cssid == 0)) ? channel_subsys.default_cssid : cssid;
1934 
1935     if (!channel_subsys.css[real_cssid]) {
1936         return NULL;
1937     }
1938 
1939     if (!channel_subsys.css[real_cssid]->sch_set[ssid]) {
1940         return NULL;
1941     }
1942 
1943     return channel_subsys.css[real_cssid]->sch_set[ssid]->sch[schid];
1944 }
1945 
1946 /**
1947  * Return free device number in subchannel set.
1948  *
1949  * Return index of the first free device number in the subchannel set
1950  * identified by @p cssid and @p ssid, beginning the search at @p
1951  * start and wrapping around at MAX_DEVNO. Return a value exceeding
1952  * MAX_SCHID if there are no free device numbers in the subchannel
1953  * set.
1954  */
1955 static uint32_t css_find_free_devno(uint8_t cssid, uint8_t ssid,
1956                                     uint16_t start)
1957 {
1958     uint32_t round;
1959 
1960     for (round = 0; round <= MAX_DEVNO; round++) {
1961         uint16_t devno = (start + round) % MAX_DEVNO;
1962 
1963         if (!css_devno_used(cssid, ssid, devno)) {
1964             return devno;
1965         }
1966     }
1967     return MAX_DEVNO + 1;
1968 }
1969 
1970 /**
1971  * Return first free subchannel (id) in subchannel set.
1972  *
1973  * Return index of the first free subchannel in the subchannel set
1974  * identified by @p cssid and @p ssid, if there is any. Return a value
1975  * exceeding MAX_SCHID if there are no free subchannels in the
1976  * subchannel set.
1977  */
1978 static uint32_t css_find_free_subch(uint8_t cssid, uint8_t ssid)
1979 {
1980     uint32_t schid;
1981 
1982     for (schid = 0; schid <= MAX_SCHID; schid++) {
1983         if (!css_find_subch(1, cssid, ssid, schid)) {
1984             return schid;
1985         }
1986     }
1987     return MAX_SCHID + 1;
1988 }
1989 
1990 /**
1991  * Return first free subchannel (id) in subchannel set for a device number
1992  *
1993  * Verify the device number @p devno is not used yet in the subchannel
1994  * set identified by @p cssid and @p ssid. Set @p schid to the index
1995  * of the first free subchannel in the subchannel set, if there is
1996  * any. Return true if everything succeeded and false otherwise.
1997  */
1998 static bool css_find_free_subch_for_devno(uint8_t cssid, uint8_t ssid,
1999                                           uint16_t devno, uint16_t *schid,
2000                                           Error **errp)
2001 {
2002     uint32_t free_schid;
2003 
2004     assert(schid);
2005     if (css_devno_used(cssid, ssid, devno)) {
2006         error_setg(errp, "Device %x.%x.%04x already exists",
2007                    cssid, ssid, devno);
2008         return false;
2009     }
2010     free_schid = css_find_free_subch(cssid, ssid);
2011     if (free_schid > MAX_SCHID) {
2012         error_setg(errp, "No free subchannel found for %x.%x.%04x",
2013                    cssid, ssid, devno);
2014         return false;
2015     }
2016     *schid = free_schid;
2017     return true;
2018 }
2019 
2020 /**
2021  * Return first free subchannel (id) and device number
2022  *
2023  * Locate the first free subchannel and first free device number in
2024  * any of the subchannel sets of the channel subsystem identified by
2025  * @p cssid. Return false if no free subchannel / device number could
2026  * be found. Otherwise set @p ssid, @p devno and @p schid to identify
2027  * the available subchannel and device number and return true.
2028  *
2029  * May modify @p ssid, @p devno and / or @p schid even if no free
2030  * subchannel / device number could be found.
2031  */
2032 static bool css_find_free_subch_and_devno(uint8_t cssid, uint8_t *ssid,
2033                                           uint16_t *devno, uint16_t *schid,
2034                                           Error **errp)
2035 {
2036     uint32_t free_schid, free_devno;
2037 
2038     assert(ssid && devno && schid);
2039     for (*ssid = 0; *ssid <= MAX_SSID; (*ssid)++) {
2040         free_schid = css_find_free_subch(cssid, *ssid);
2041         if (free_schid > MAX_SCHID) {
2042             continue;
2043         }
2044         free_devno = css_find_free_devno(cssid, *ssid, free_schid);
2045         if (free_devno > MAX_DEVNO) {
2046             continue;
2047         }
2048         *schid = free_schid;
2049         *devno = free_devno;
2050         return true;
2051     }
2052     error_setg(errp, "Virtual channel subsystem is full!");
2053     return false;
2054 }
2055 
2056 bool css_subch_visible(SubchDev *sch)
2057 {
2058     if (sch->ssid > channel_subsys.max_ssid) {
2059         return false;
2060     }
2061 
2062     if (sch->cssid != channel_subsys.default_cssid) {
2063         return (channel_subsys.max_cssid > 0);
2064     }
2065 
2066     return true;
2067 }
2068 
2069 bool css_present(uint8_t cssid)
2070 {
2071     return (channel_subsys.css[cssid] != NULL);
2072 }
2073 
2074 bool css_devno_used(uint8_t cssid, uint8_t ssid, uint16_t devno)
2075 {
2076     if (!channel_subsys.css[cssid]) {
2077         return false;
2078     }
2079     if (!channel_subsys.css[cssid]->sch_set[ssid]) {
2080         return false;
2081     }
2082 
2083     return !!test_bit(devno,
2084                       channel_subsys.css[cssid]->sch_set[ssid]->devnos_used);
2085 }
2086 
2087 void css_subch_assign(uint8_t cssid, uint8_t ssid, uint16_t schid,
2088                       uint16_t devno, SubchDev *sch)
2089 {
2090     CssImage *css;
2091     SubchSet *s_set;
2092 
2093     trace_css_assign_subch(sch ? "assign" : "deassign", cssid, ssid, schid,
2094                            devno);
2095     if (!channel_subsys.css[cssid]) {
2096         fprintf(stderr,
2097                 "Suspicious call to %s (%x.%x.%04x) for non-existing css!\n",
2098                 __func__, cssid, ssid, schid);
2099         return;
2100     }
2101     css = channel_subsys.css[cssid];
2102 
2103     if (!css->sch_set[ssid]) {
2104         css->sch_set[ssid] = g_new0(SubchSet, 1);
2105     }
2106     s_set = css->sch_set[ssid];
2107 
2108     s_set->sch[schid] = sch;
2109     if (sch) {
2110         set_bit(schid, s_set->schids_used);
2111         set_bit(devno, s_set->devnos_used);
2112     } else {
2113         clear_bit(schid, s_set->schids_used);
2114         clear_bit(devno, s_set->devnos_used);
2115     }
2116 }
2117 
2118 void css_queue_crw(uint8_t rsc, uint8_t erc, int solicited,
2119                    int chain, uint16_t rsid)
2120 {
2121     CrwContainer *crw_cont;
2122 
2123     trace_css_crw(rsc, erc, rsid, chain ? "(chained)" : "");
2124     /* TODO: Maybe use a static crw pool? */
2125     crw_cont = g_try_new0(CrwContainer, 1);
2126     if (!crw_cont) {
2127         channel_subsys.crws_lost = true;
2128         return;
2129     }
2130     crw_cont->crw.flags = (rsc << 8) | erc;
2131     if (solicited) {
2132         crw_cont->crw.flags |= CRW_FLAGS_MASK_S;
2133     }
2134     if (chain) {
2135         crw_cont->crw.flags |= CRW_FLAGS_MASK_C;
2136     }
2137     crw_cont->crw.rsid = rsid;
2138     if (channel_subsys.crws_lost) {
2139         crw_cont->crw.flags |= CRW_FLAGS_MASK_R;
2140         channel_subsys.crws_lost = false;
2141     }
2142 
2143     QTAILQ_INSERT_TAIL(&channel_subsys.pending_crws, crw_cont, sibling);
2144 
2145     if (channel_subsys.do_crw_mchk) {
2146         channel_subsys.do_crw_mchk = false;
2147         /* Inject crw pending machine check. */
2148         s390_crw_mchk();
2149     }
2150 }
2151 
2152 void css_generate_sch_crws(uint8_t cssid, uint8_t ssid, uint16_t schid,
2153                            int hotplugged, int add)
2154 {
2155     uint8_t guest_cssid;
2156     bool chain_crw;
2157 
2158     if (add && !hotplugged) {
2159         return;
2160     }
2161     if (channel_subsys.max_cssid == 0) {
2162         /* Default cssid shows up as 0. */
2163         guest_cssid = (cssid == channel_subsys.default_cssid) ? 0 : cssid;
2164     } else {
2165         /* Show real cssid to the guest. */
2166         guest_cssid = cssid;
2167     }
2168     /*
2169      * Only notify for higher subchannel sets/channel subsystems if the
2170      * guest has enabled it.
2171      */
2172     if ((ssid > channel_subsys.max_ssid) ||
2173         (guest_cssid > channel_subsys.max_cssid) ||
2174         ((channel_subsys.max_cssid == 0) &&
2175          (cssid != channel_subsys.default_cssid))) {
2176         return;
2177     }
2178     chain_crw = (channel_subsys.max_ssid > 0) ||
2179             (channel_subsys.max_cssid > 0);
2180     css_queue_crw(CRW_RSC_SUBCH, CRW_ERC_IPI, 0, chain_crw ? 1 : 0, schid);
2181     if (chain_crw) {
2182         css_queue_crw(CRW_RSC_SUBCH, CRW_ERC_IPI, 0, 0,
2183                       (guest_cssid << 8) | (ssid << 4));
2184     }
2185     /* RW_ERC_IPI --> clear pending interrupts */
2186     css_clear_io_interrupt(css_do_build_subchannel_id(cssid, ssid), schid);
2187 }
2188 
2189 void css_generate_chp_crws(uint8_t cssid, uint8_t chpid)
2190 {
2191     /* TODO */
2192 }
2193 
2194 void css_generate_css_crws(uint8_t cssid)
2195 {
2196     if (!channel_subsys.sei_pending) {
2197         css_queue_crw(CRW_RSC_CSS, CRW_ERC_EVENT, 0, 0, cssid);
2198     }
2199     channel_subsys.sei_pending = true;
2200 }
2201 
2202 void css_clear_sei_pending(void)
2203 {
2204     channel_subsys.sei_pending = false;
2205 }
2206 
2207 int css_enable_mcsse(void)
2208 {
2209     trace_css_enable_facility("mcsse");
2210     channel_subsys.max_cssid = MAX_CSSID;
2211     return 0;
2212 }
2213 
2214 int css_enable_mss(void)
2215 {
2216     trace_css_enable_facility("mss");
2217     channel_subsys.max_ssid = MAX_SSID;
2218     return 0;
2219 }
2220 
2221 void css_reset_sch(SubchDev *sch)
2222 {
2223     PMCW *p = &sch->curr_status.pmcw;
2224 
2225     if ((p->flags & PMCW_FLAGS_MASK_ENA) != 0 && sch->disable_cb) {
2226         sch->disable_cb(sch);
2227     }
2228 
2229     p->intparm = 0;
2230     p->flags &= ~(PMCW_FLAGS_MASK_ISC | PMCW_FLAGS_MASK_ENA |
2231                   PMCW_FLAGS_MASK_LM | PMCW_FLAGS_MASK_MME |
2232                   PMCW_FLAGS_MASK_MP | PMCW_FLAGS_MASK_TF);
2233     p->flags |= PMCW_FLAGS_MASK_DNV;
2234     p->devno = sch->devno;
2235     p->pim = 0x80;
2236     p->lpm = p->pim;
2237     p->pnom = 0;
2238     p->lpum = 0;
2239     p->mbi = 0;
2240     p->pom = 0xff;
2241     p->pam = 0x80;
2242     p->chars &= ~(PMCW_CHARS_MASK_MBFC | PMCW_CHARS_MASK_XMWME |
2243                   PMCW_CHARS_MASK_CSENSE);
2244 
2245     memset(&sch->curr_status.scsw, 0, sizeof(sch->curr_status.scsw));
2246     sch->curr_status.mba = 0;
2247 
2248     sch->channel_prog = 0x0;
2249     sch->last_cmd_valid = false;
2250     sch->thinint_active = false;
2251 }
2252 
2253 void css_reset(void)
2254 {
2255     CrwContainer *crw_cont;
2256 
2257     /* Clean up monitoring. */
2258     channel_subsys.chnmon_active = false;
2259     channel_subsys.chnmon_area = 0;
2260 
2261     /* Clear pending CRWs. */
2262     while ((crw_cont = QTAILQ_FIRST(&channel_subsys.pending_crws))) {
2263         QTAILQ_REMOVE(&channel_subsys.pending_crws, crw_cont, sibling);
2264         g_free(crw_cont);
2265     }
2266     channel_subsys.sei_pending = false;
2267     channel_subsys.do_crw_mchk = true;
2268     channel_subsys.crws_lost = false;
2269 
2270     /* Reset maximum ids. */
2271     channel_subsys.max_cssid = 0;
2272     channel_subsys.max_ssid = 0;
2273 }
2274 
2275 static void get_css_devid(Object *obj, Visitor *v, const char *name,
2276                           void *opaque, Error **errp)
2277 {
2278     DeviceState *dev = DEVICE(obj);
2279     Property *prop = opaque;
2280     CssDevId *dev_id = qdev_get_prop_ptr(dev, prop);
2281     char buffer[] = "xx.x.xxxx";
2282     char *p = buffer;
2283     int r;
2284 
2285     if (dev_id->valid) {
2286 
2287         r = snprintf(buffer, sizeof(buffer), "%02x.%1x.%04x", dev_id->cssid,
2288                      dev_id->ssid, dev_id->devid);
2289         assert(r == sizeof(buffer) - 1);
2290 
2291         /* drop leading zero */
2292         if (dev_id->cssid <= 0xf) {
2293             p++;
2294         }
2295     } else {
2296         snprintf(buffer, sizeof(buffer), "<unset>");
2297     }
2298 
2299     visit_type_str(v, name, &p, errp);
2300 }
2301 
2302 /*
2303  * parse <cssid>.<ssid>.<devid> and assert valid range for cssid/ssid
2304  */
2305 static void set_css_devid(Object *obj, Visitor *v, const char *name,
2306                           void *opaque, Error **errp)
2307 {
2308     DeviceState *dev = DEVICE(obj);
2309     Property *prop = opaque;
2310     CssDevId *dev_id = qdev_get_prop_ptr(dev, prop);
2311     Error *local_err = NULL;
2312     char *str;
2313     int num, n1, n2;
2314     unsigned int cssid, ssid, devid;
2315 
2316     if (dev->realized) {
2317         qdev_prop_set_after_realize(dev, name, errp);
2318         return;
2319     }
2320 
2321     visit_type_str(v, name, &str, &local_err);
2322     if (local_err) {
2323         error_propagate(errp, local_err);
2324         return;
2325     }
2326 
2327     num = sscanf(str, "%2x.%1x%n.%4x%n", &cssid, &ssid, &n1, &devid, &n2);
2328     if (num != 3 || (n2 - n1) != 5 || strlen(str) != n2) {
2329         error_set_from_qdev_prop_error(errp, EINVAL, dev, prop, str);
2330         goto out;
2331     }
2332     if ((cssid > MAX_CSSID) || (ssid > MAX_SSID)) {
2333         error_setg(errp, "Invalid cssid or ssid: cssid %x, ssid %x",
2334                    cssid, ssid);
2335         goto out;
2336     }
2337 
2338     dev_id->cssid = cssid;
2339     dev_id->ssid = ssid;
2340     dev_id->devid = devid;
2341     dev_id->valid = true;
2342 
2343 out:
2344     g_free(str);
2345 }
2346 
2347 const PropertyInfo css_devid_propinfo = {
2348     .name = "str",
2349     .description = "Identifier of an I/O device in the channel "
2350                    "subsystem, example: fe.1.23ab",
2351     .get = get_css_devid,
2352     .set = set_css_devid,
2353 };
2354 
2355 const PropertyInfo css_devid_ro_propinfo = {
2356     .name = "str",
2357     .description = "Read-only identifier of an I/O device in the channel "
2358                    "subsystem, example: fe.1.23ab",
2359     .get = get_css_devid,
2360 };
2361 
2362 SubchDev *css_create_sch(CssDevId bus_id, Error **errp)
2363 {
2364     uint16_t schid = 0;
2365     SubchDev *sch;
2366 
2367     if (bus_id.valid) {
2368         if (!channel_subsys.css[bus_id.cssid]) {
2369             css_create_css_image(bus_id.cssid, false);
2370         }
2371 
2372         if (!css_find_free_subch_for_devno(bus_id.cssid, bus_id.ssid,
2373                                            bus_id.devid, &schid, errp)) {
2374             return NULL;
2375         }
2376     } else {
2377         for (bus_id.cssid = channel_subsys.default_cssid;;) {
2378             if (!channel_subsys.css[bus_id.cssid]) {
2379                 css_create_css_image(bus_id.cssid, false);
2380             }
2381 
2382             if   (css_find_free_subch_and_devno(bus_id.cssid, &bus_id.ssid,
2383                                                 &bus_id.devid, &schid,
2384                                                 NULL)) {
2385                 break;
2386             }
2387             bus_id.cssid = (bus_id.cssid + 1) % MAX_CSSID;
2388             if (bus_id.cssid == channel_subsys.default_cssid) {
2389                 error_setg(errp, "Virtual channel subsystem is full!");
2390                 return NULL;
2391             }
2392         }
2393     }
2394 
2395     sch = g_new0(SubchDev, 1);
2396     sch->cssid = bus_id.cssid;
2397     sch->ssid = bus_id.ssid;
2398     sch->devno = bus_id.devid;
2399     sch->schid = schid;
2400     css_subch_assign(sch->cssid, sch->ssid, schid, sch->devno, sch);
2401     return sch;
2402 }
2403 
2404 static int css_sch_get_chpids(SubchDev *sch, CssDevId *dev_id)
2405 {
2406     char *fid_path;
2407     FILE *fd;
2408     uint32_t chpid[8];
2409     int i;
2410     PMCW *p = &sch->curr_status.pmcw;
2411 
2412     fid_path = g_strdup_printf("/sys/bus/css/devices/%x.%x.%04x/chpids",
2413                                dev_id->cssid, dev_id->ssid, dev_id->devid);
2414     fd = fopen(fid_path, "r");
2415     if (fd == NULL) {
2416         error_report("%s: open %s failed", __func__, fid_path);
2417         g_free(fid_path);
2418         return -EINVAL;
2419     }
2420 
2421     if (fscanf(fd, "%x %x %x %x %x %x %x %x",
2422         &chpid[0], &chpid[1], &chpid[2], &chpid[3],
2423         &chpid[4], &chpid[5], &chpid[6], &chpid[7]) != 8) {
2424         fclose(fd);
2425         g_free(fid_path);
2426         return -EINVAL;
2427     }
2428 
2429     for (i = 0; i < ARRAY_SIZE(p->chpid); i++) {
2430         p->chpid[i] = chpid[i];
2431     }
2432 
2433     fclose(fd);
2434     g_free(fid_path);
2435 
2436     return 0;
2437 }
2438 
2439 static int css_sch_get_path_masks(SubchDev *sch, CssDevId *dev_id)
2440 {
2441     char *fid_path;
2442     FILE *fd;
2443     uint32_t pim, pam, pom;
2444     PMCW *p = &sch->curr_status.pmcw;
2445 
2446     fid_path = g_strdup_printf("/sys/bus/css/devices/%x.%x.%04x/pimpampom",
2447                                dev_id->cssid, dev_id->ssid, dev_id->devid);
2448     fd = fopen(fid_path, "r");
2449     if (fd == NULL) {
2450         error_report("%s: open %s failed", __func__, fid_path);
2451         g_free(fid_path);
2452         return -EINVAL;
2453     }
2454 
2455     if (fscanf(fd, "%x %x %x", &pim, &pam, &pom) != 3) {
2456         fclose(fd);
2457         g_free(fid_path);
2458         return -EINVAL;
2459     }
2460 
2461     p->pim = pim;
2462     p->pam = pam;
2463     p->pom = pom;
2464     fclose(fd);
2465     g_free(fid_path);
2466 
2467     return 0;
2468 }
2469 
2470 static int css_sch_get_chpid_type(uint8_t chpid, uint32_t *type,
2471                                   CssDevId *dev_id)
2472 {
2473     char *fid_path;
2474     FILE *fd;
2475 
2476     fid_path = g_strdup_printf("/sys/devices/css%x/chp0.%02x/type",
2477                                dev_id->cssid, chpid);
2478     fd = fopen(fid_path, "r");
2479     if (fd == NULL) {
2480         error_report("%s: open %s failed", __func__, fid_path);
2481         g_free(fid_path);
2482         return -EINVAL;
2483     }
2484 
2485     if (fscanf(fd, "%x", type) != 1) {
2486         fclose(fd);
2487         g_free(fid_path);
2488         return -EINVAL;
2489     }
2490 
2491     fclose(fd);
2492     g_free(fid_path);
2493 
2494     return 0;
2495 }
2496 
2497 /*
2498  * We currently retrieve the real device information from sysfs to build the
2499  * guest subchannel information block without considering the migration feature.
2500  * We need to revisit this problem when we want to add migration support.
2501  */
2502 int css_sch_build_schib(SubchDev *sch, CssDevId *dev_id)
2503 {
2504     CssImage *css = channel_subsys.css[sch->cssid];
2505     PMCW *p = &sch->curr_status.pmcw;
2506     SCSW *s = &sch->curr_status.scsw;
2507     uint32_t type;
2508     int i, ret;
2509 
2510     assert(css != NULL);
2511     memset(p, 0, sizeof(PMCW));
2512     p->flags |= PMCW_FLAGS_MASK_DNV;
2513     /* We are dealing with I/O subchannels only. */
2514     p->devno = sch->devno;
2515 
2516     /* Grab path mask from sysfs. */
2517     ret = css_sch_get_path_masks(sch, dev_id);
2518     if (ret) {
2519         return ret;
2520     }
2521 
2522     /* Grab chpids from sysfs. */
2523     ret = css_sch_get_chpids(sch, dev_id);
2524     if (ret) {
2525         return ret;
2526     }
2527 
2528    /* Build chpid type. */
2529     for (i = 0; i < ARRAY_SIZE(p->chpid); i++) {
2530         if (p->chpid[i] && !css->chpids[p->chpid[i]].in_use) {
2531             ret = css_sch_get_chpid_type(p->chpid[i], &type, dev_id);
2532             if (ret) {
2533                 return ret;
2534             }
2535             css_add_chpid(sch->cssid, p->chpid[i], type, false);
2536         }
2537     }
2538 
2539     memset(s, 0, sizeof(SCSW));
2540     sch->curr_status.mba = 0;
2541     for (i = 0; i < ARRAY_SIZE(sch->curr_status.mda); i++) {
2542         sch->curr_status.mda[i] = 0;
2543     }
2544 
2545     return 0;
2546 }
2547