xref: /openbmc/qemu/hw/s390x/css.c (revision 4a4ff4c5)
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 
1203     /*
1204      * Only support prefetch enable mode.
1205      * Only support 64bit addressing idal.
1206      */
1207     if (!(orb->ctrl0 & ORB_CTRL0_MASK_PFCH) ||
1208         !(orb->ctrl0 & ORB_CTRL0_MASK_C64)) {
1209         warn_report("vfio-ccw requires PFCH and C64 flags set");
1210         sch_gen_unit_exception(sch);
1211         css_inject_io_interrupt(sch);
1212         return IOINST_CC_EXPECTED;
1213     }
1214     return s390_ccw_cmd_request(sch);
1215 }
1216 
1217 /*
1218  * On real machines, this would run asynchronously to the main vcpus.
1219  * We might want to make some parts of the ssch handling (interpreting
1220  * read/writes) asynchronous later on if we start supporting more than
1221  * our current very simple devices.
1222  */
1223 IOInstEnding do_subchannel_work_virtual(SubchDev *sch)
1224 {
1225 
1226     SCSW *s = &sch->curr_status.scsw;
1227 
1228     if (s->ctrl & SCSW_FCTL_CLEAR_FUNC) {
1229         sch_handle_clear_func(sch);
1230     } else if (s->ctrl & SCSW_FCTL_HALT_FUNC) {
1231         sch_handle_halt_func(sch);
1232     } else if (s->ctrl & SCSW_FCTL_START_FUNC) {
1233         /* Triggered by both ssch and rsch. */
1234         sch_handle_start_func_virtual(sch);
1235     }
1236     css_inject_io_interrupt(sch);
1237     /* inst must succeed if this func is called */
1238     return IOINST_CC_EXPECTED;
1239 }
1240 
1241 IOInstEnding do_subchannel_work_passthrough(SubchDev *sch)
1242 {
1243     SCSW *s = &sch->curr_status.scsw;
1244 
1245     if (s->ctrl & SCSW_FCTL_CLEAR_FUNC) {
1246         /* TODO: Clear handling */
1247         sch_handle_clear_func(sch);
1248     } else if (s->ctrl & SCSW_FCTL_HALT_FUNC) {
1249         /* TODO: Halt handling */
1250         sch_handle_halt_func(sch);
1251     } else if (s->ctrl & SCSW_FCTL_START_FUNC) {
1252         return sch_handle_start_func_passthrough(sch);
1253     }
1254     return IOINST_CC_EXPECTED;
1255 }
1256 
1257 static IOInstEnding do_subchannel_work(SubchDev *sch)
1258 {
1259     if (!sch->do_subchannel_work) {
1260         return IOINST_CC_STATUS_PRESENT;
1261     }
1262     g_assert(sch->curr_status.scsw.ctrl & SCSW_CTRL_MASK_FCTL);
1263     return sch->do_subchannel_work(sch);
1264 }
1265 
1266 static void copy_pmcw_to_guest(PMCW *dest, const PMCW *src)
1267 {
1268     int i;
1269 
1270     dest->intparm = cpu_to_be32(src->intparm);
1271     dest->flags = cpu_to_be16(src->flags);
1272     dest->devno = cpu_to_be16(src->devno);
1273     dest->lpm = src->lpm;
1274     dest->pnom = src->pnom;
1275     dest->lpum = src->lpum;
1276     dest->pim = src->pim;
1277     dest->mbi = cpu_to_be16(src->mbi);
1278     dest->pom = src->pom;
1279     dest->pam = src->pam;
1280     for (i = 0; i < ARRAY_SIZE(dest->chpid); i++) {
1281         dest->chpid[i] = src->chpid[i];
1282     }
1283     dest->chars = cpu_to_be32(src->chars);
1284 }
1285 
1286 void copy_scsw_to_guest(SCSW *dest, const SCSW *src)
1287 {
1288     dest->flags = cpu_to_be16(src->flags);
1289     dest->ctrl = cpu_to_be16(src->ctrl);
1290     dest->cpa = cpu_to_be32(src->cpa);
1291     dest->dstat = src->dstat;
1292     dest->cstat = src->cstat;
1293     dest->count = cpu_to_be16(src->count);
1294 }
1295 
1296 static void copy_schib_to_guest(SCHIB *dest, const SCHIB *src)
1297 {
1298     int i;
1299 
1300     copy_pmcw_to_guest(&dest->pmcw, &src->pmcw);
1301     copy_scsw_to_guest(&dest->scsw, &src->scsw);
1302     dest->mba = cpu_to_be64(src->mba);
1303     for (i = 0; i < ARRAY_SIZE(dest->mda); i++) {
1304         dest->mda[i] = src->mda[i];
1305     }
1306 }
1307 
1308 int css_do_stsch(SubchDev *sch, SCHIB *schib)
1309 {
1310     /* Use current status. */
1311     copy_schib_to_guest(schib, &sch->curr_status);
1312     return 0;
1313 }
1314 
1315 static void copy_pmcw_from_guest(PMCW *dest, const PMCW *src)
1316 {
1317     int i;
1318 
1319     dest->intparm = be32_to_cpu(src->intparm);
1320     dest->flags = be16_to_cpu(src->flags);
1321     dest->devno = be16_to_cpu(src->devno);
1322     dest->lpm = src->lpm;
1323     dest->pnom = src->pnom;
1324     dest->lpum = src->lpum;
1325     dest->pim = src->pim;
1326     dest->mbi = be16_to_cpu(src->mbi);
1327     dest->pom = src->pom;
1328     dest->pam = src->pam;
1329     for (i = 0; i < ARRAY_SIZE(dest->chpid); i++) {
1330         dest->chpid[i] = src->chpid[i];
1331     }
1332     dest->chars = be32_to_cpu(src->chars);
1333 }
1334 
1335 static void copy_scsw_from_guest(SCSW *dest, const SCSW *src)
1336 {
1337     dest->flags = be16_to_cpu(src->flags);
1338     dest->ctrl = be16_to_cpu(src->ctrl);
1339     dest->cpa = be32_to_cpu(src->cpa);
1340     dest->dstat = src->dstat;
1341     dest->cstat = src->cstat;
1342     dest->count = be16_to_cpu(src->count);
1343 }
1344 
1345 static void copy_schib_from_guest(SCHIB *dest, const SCHIB *src)
1346 {
1347     int i;
1348 
1349     copy_pmcw_from_guest(&dest->pmcw, &src->pmcw);
1350     copy_scsw_from_guest(&dest->scsw, &src->scsw);
1351     dest->mba = be64_to_cpu(src->mba);
1352     for (i = 0; i < ARRAY_SIZE(dest->mda); i++) {
1353         dest->mda[i] = src->mda[i];
1354     }
1355 }
1356 
1357 IOInstEnding css_do_msch(SubchDev *sch, const SCHIB *orig_schib)
1358 {
1359     SCSW *s = &sch->curr_status.scsw;
1360     PMCW *p = &sch->curr_status.pmcw;
1361     uint16_t oldflags;
1362     SCHIB schib;
1363 
1364     if (!(sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_DNV)) {
1365         return IOINST_CC_EXPECTED;
1366     }
1367 
1368     if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
1369         return IOINST_CC_STATUS_PRESENT;
1370     }
1371 
1372     if (s->ctrl &
1373         (SCSW_FCTL_START_FUNC|SCSW_FCTL_HALT_FUNC|SCSW_FCTL_CLEAR_FUNC)) {
1374         return IOINST_CC_BUSY;
1375     }
1376 
1377     copy_schib_from_guest(&schib, orig_schib);
1378     /* Only update the program-modifiable fields. */
1379     p->intparm = schib.pmcw.intparm;
1380     oldflags = p->flags;
1381     p->flags &= ~(PMCW_FLAGS_MASK_ISC | PMCW_FLAGS_MASK_ENA |
1382                   PMCW_FLAGS_MASK_LM | PMCW_FLAGS_MASK_MME |
1383                   PMCW_FLAGS_MASK_MP);
1384     p->flags |= schib.pmcw.flags &
1385             (PMCW_FLAGS_MASK_ISC | PMCW_FLAGS_MASK_ENA |
1386              PMCW_FLAGS_MASK_LM | PMCW_FLAGS_MASK_MME |
1387              PMCW_FLAGS_MASK_MP);
1388     p->lpm = schib.pmcw.lpm;
1389     p->mbi = schib.pmcw.mbi;
1390     p->pom = schib.pmcw.pom;
1391     p->chars &= ~(PMCW_CHARS_MASK_MBFC | PMCW_CHARS_MASK_CSENSE);
1392     p->chars |= schib.pmcw.chars &
1393             (PMCW_CHARS_MASK_MBFC | PMCW_CHARS_MASK_CSENSE);
1394     sch->curr_status.mba = schib.mba;
1395 
1396     /* Has the channel been disabled? */
1397     if (sch->disable_cb && (oldflags & PMCW_FLAGS_MASK_ENA) != 0
1398         && (p->flags & PMCW_FLAGS_MASK_ENA) == 0) {
1399         sch->disable_cb(sch);
1400     }
1401     return IOINST_CC_EXPECTED;
1402 }
1403 
1404 IOInstEnding css_do_xsch(SubchDev *sch)
1405 {
1406     SCSW *s = &sch->curr_status.scsw;
1407     PMCW *p = &sch->curr_status.pmcw;
1408 
1409     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1410         return IOINST_CC_NOT_OPERATIONAL;
1411     }
1412 
1413     if (s->ctrl & SCSW_CTRL_MASK_STCTL) {
1414         return IOINST_CC_STATUS_PRESENT;
1415     }
1416 
1417     if (!(s->ctrl & SCSW_CTRL_MASK_FCTL) ||
1418         ((s->ctrl & SCSW_CTRL_MASK_FCTL) != SCSW_FCTL_START_FUNC) ||
1419         (!(s->ctrl &
1420            (SCSW_ACTL_RESUME_PEND | SCSW_ACTL_START_PEND | SCSW_ACTL_SUSP))) ||
1421         (s->ctrl & SCSW_ACTL_SUBCH_ACTIVE)) {
1422         return IOINST_CC_BUSY;
1423     }
1424 
1425     /* Cancel the current operation. */
1426     s->ctrl &= ~(SCSW_FCTL_START_FUNC |
1427                  SCSW_ACTL_RESUME_PEND |
1428                  SCSW_ACTL_START_PEND |
1429                  SCSW_ACTL_SUSP);
1430     sch->channel_prog = 0x0;
1431     sch->last_cmd_valid = false;
1432     s->dstat = 0;
1433     s->cstat = 0;
1434     return IOINST_CC_EXPECTED;
1435 }
1436 
1437 IOInstEnding css_do_csch(SubchDev *sch)
1438 {
1439     SCSW *s = &sch->curr_status.scsw;
1440     PMCW *p = &sch->curr_status.pmcw;
1441 
1442     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1443         return IOINST_CC_NOT_OPERATIONAL;
1444     }
1445 
1446     /* Trigger the clear function. */
1447     s->ctrl &= ~(SCSW_CTRL_MASK_FCTL | SCSW_CTRL_MASK_ACTL);
1448     s->ctrl |= SCSW_FCTL_CLEAR_FUNC | SCSW_ACTL_CLEAR_PEND;
1449 
1450     return do_subchannel_work(sch);
1451 }
1452 
1453 IOInstEnding css_do_hsch(SubchDev *sch)
1454 {
1455     SCSW *s = &sch->curr_status.scsw;
1456     PMCW *p = &sch->curr_status.pmcw;
1457 
1458     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1459         return IOINST_CC_NOT_OPERATIONAL;
1460     }
1461 
1462     if (((s->ctrl & SCSW_CTRL_MASK_STCTL) == SCSW_STCTL_STATUS_PEND) ||
1463         (s->ctrl & (SCSW_STCTL_PRIMARY |
1464                     SCSW_STCTL_SECONDARY |
1465                     SCSW_STCTL_ALERT))) {
1466         return IOINST_CC_STATUS_PRESENT;
1467     }
1468 
1469     if (s->ctrl & (SCSW_FCTL_HALT_FUNC | SCSW_FCTL_CLEAR_FUNC)) {
1470         return IOINST_CC_BUSY;
1471     }
1472 
1473     /* Trigger the halt function. */
1474     s->ctrl |= SCSW_FCTL_HALT_FUNC;
1475     s->ctrl &= ~SCSW_FCTL_START_FUNC;
1476     if (((s->ctrl & SCSW_CTRL_MASK_ACTL) ==
1477          (SCSW_ACTL_SUBCH_ACTIVE | SCSW_ACTL_DEVICE_ACTIVE)) &&
1478         ((s->ctrl & SCSW_CTRL_MASK_STCTL) == SCSW_STCTL_INTERMEDIATE)) {
1479         s->ctrl &= ~SCSW_STCTL_STATUS_PEND;
1480     }
1481     s->ctrl |= SCSW_ACTL_HALT_PEND;
1482 
1483     return do_subchannel_work(sch);
1484 }
1485 
1486 static void css_update_chnmon(SubchDev *sch)
1487 {
1488     if (!(sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_MME)) {
1489         /* Not active. */
1490         return;
1491     }
1492     /* The counter is conveniently located at the beginning of the struct. */
1493     if (sch->curr_status.pmcw.chars & PMCW_CHARS_MASK_MBFC) {
1494         /* Format 1, per-subchannel area. */
1495         uint32_t count;
1496 
1497         count = address_space_ldl(&address_space_memory,
1498                                   sch->curr_status.mba,
1499                                   MEMTXATTRS_UNSPECIFIED,
1500                                   NULL);
1501         count++;
1502         address_space_stl(&address_space_memory, sch->curr_status.mba, count,
1503                           MEMTXATTRS_UNSPECIFIED, NULL);
1504     } else {
1505         /* Format 0, global area. */
1506         uint32_t offset;
1507         uint16_t count;
1508 
1509         offset = sch->curr_status.pmcw.mbi << 5;
1510         count = address_space_lduw(&address_space_memory,
1511                                    channel_subsys.chnmon_area + offset,
1512                                    MEMTXATTRS_UNSPECIFIED,
1513                                    NULL);
1514         count++;
1515         address_space_stw(&address_space_memory,
1516                           channel_subsys.chnmon_area + offset, count,
1517                           MEMTXATTRS_UNSPECIFIED, NULL);
1518     }
1519 }
1520 
1521 IOInstEnding css_do_ssch(SubchDev *sch, ORB *orb)
1522 {
1523     SCSW *s = &sch->curr_status.scsw;
1524     PMCW *p = &sch->curr_status.pmcw;
1525 
1526     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1527         return IOINST_CC_NOT_OPERATIONAL;
1528     }
1529 
1530     if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
1531         return IOINST_CC_STATUS_PRESENT;
1532     }
1533 
1534     if (s->ctrl & (SCSW_FCTL_START_FUNC |
1535                    SCSW_FCTL_HALT_FUNC |
1536                    SCSW_FCTL_CLEAR_FUNC)) {
1537         return IOINST_CC_BUSY;
1538     }
1539 
1540     /* If monitoring is active, update counter. */
1541     if (channel_subsys.chnmon_active) {
1542         css_update_chnmon(sch);
1543     }
1544     sch->orb = *orb;
1545     sch->channel_prog = orb->cpa;
1546     /* Trigger the start function. */
1547     s->ctrl |= (SCSW_FCTL_START_FUNC | SCSW_ACTL_START_PEND);
1548     s->flags &= ~SCSW_FLAGS_MASK_PNO;
1549 
1550     return do_subchannel_work(sch);
1551 }
1552 
1553 static void copy_irb_to_guest(IRB *dest, const IRB *src, PMCW *pmcw,
1554                               int *irb_len)
1555 {
1556     int i;
1557     uint16_t stctl = src->scsw.ctrl & SCSW_CTRL_MASK_STCTL;
1558     uint16_t actl = src->scsw.ctrl & SCSW_CTRL_MASK_ACTL;
1559 
1560     copy_scsw_to_guest(&dest->scsw, &src->scsw);
1561 
1562     for (i = 0; i < ARRAY_SIZE(dest->esw); i++) {
1563         dest->esw[i] = cpu_to_be32(src->esw[i]);
1564     }
1565     for (i = 0; i < ARRAY_SIZE(dest->ecw); i++) {
1566         dest->ecw[i] = cpu_to_be32(src->ecw[i]);
1567     }
1568     *irb_len = sizeof(*dest) - sizeof(dest->emw);
1569 
1570     /* extended measurements enabled? */
1571     if ((src->scsw.flags & SCSW_FLAGS_MASK_ESWF) ||
1572         !(pmcw->flags & PMCW_FLAGS_MASK_TF) ||
1573         !(pmcw->chars & PMCW_CHARS_MASK_XMWME)) {
1574         return;
1575     }
1576     /* extended measurements pending? */
1577     if (!(stctl & SCSW_STCTL_STATUS_PEND)) {
1578         return;
1579     }
1580     if ((stctl & SCSW_STCTL_PRIMARY) ||
1581         (stctl == SCSW_STCTL_SECONDARY) ||
1582         ((stctl & SCSW_STCTL_INTERMEDIATE) && (actl & SCSW_ACTL_SUSP))) {
1583         for (i = 0; i < ARRAY_SIZE(dest->emw); i++) {
1584             dest->emw[i] = cpu_to_be32(src->emw[i]);
1585         }
1586     }
1587     *irb_len = sizeof(*dest);
1588 }
1589 
1590 int css_do_tsch_get_irb(SubchDev *sch, IRB *target_irb, int *irb_len)
1591 {
1592     SCSW *s = &sch->curr_status.scsw;
1593     PMCW *p = &sch->curr_status.pmcw;
1594     uint16_t stctl;
1595     IRB irb;
1596 
1597     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1598         return 3;
1599     }
1600 
1601     stctl = s->ctrl & SCSW_CTRL_MASK_STCTL;
1602 
1603     /* Prepare the irb for the guest. */
1604     memset(&irb, 0, sizeof(IRB));
1605 
1606     /* Copy scsw from current status. */
1607     memcpy(&irb.scsw, s, sizeof(SCSW));
1608     if (stctl & SCSW_STCTL_STATUS_PEND) {
1609         if (s->cstat & (SCSW_CSTAT_DATA_CHECK |
1610                         SCSW_CSTAT_CHN_CTRL_CHK |
1611                         SCSW_CSTAT_INTF_CTRL_CHK)) {
1612             irb.scsw.flags |= SCSW_FLAGS_MASK_ESWF;
1613             irb.esw[0] = 0x04804000;
1614         } else {
1615             irb.esw[0] = 0x00800000;
1616         }
1617         /* If a unit check is pending, copy sense data. */
1618         if ((s->dstat & SCSW_DSTAT_UNIT_CHECK) &&
1619             (p->chars & PMCW_CHARS_MASK_CSENSE)) {
1620             int i;
1621 
1622             irb.scsw.flags |= SCSW_FLAGS_MASK_ESWF | SCSW_FLAGS_MASK_ECTL;
1623             /* Attention: sense_data is already BE! */
1624             memcpy(irb.ecw, sch->sense_data, sizeof(sch->sense_data));
1625             for (i = 0; i < ARRAY_SIZE(irb.ecw); i++) {
1626                 irb.ecw[i] = be32_to_cpu(irb.ecw[i]);
1627             }
1628             irb.esw[1] = 0x01000000 | (sizeof(sch->sense_data) << 8);
1629         }
1630     }
1631     /* Store the irb to the guest. */
1632     copy_irb_to_guest(target_irb, &irb, p, irb_len);
1633 
1634     return ((stctl & SCSW_STCTL_STATUS_PEND) == 0);
1635 }
1636 
1637 void css_do_tsch_update_subch(SubchDev *sch)
1638 {
1639     SCSW *s = &sch->curr_status.scsw;
1640     PMCW *p = &sch->curr_status.pmcw;
1641     uint16_t stctl;
1642     uint16_t fctl;
1643     uint16_t actl;
1644 
1645     stctl = s->ctrl & SCSW_CTRL_MASK_STCTL;
1646     fctl = s->ctrl & SCSW_CTRL_MASK_FCTL;
1647     actl = s->ctrl & SCSW_CTRL_MASK_ACTL;
1648 
1649     /* Clear conditions on subchannel, if applicable. */
1650     if (stctl & SCSW_STCTL_STATUS_PEND) {
1651         s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
1652         if ((stctl != (SCSW_STCTL_INTERMEDIATE | SCSW_STCTL_STATUS_PEND)) ||
1653             ((fctl & SCSW_FCTL_HALT_FUNC) &&
1654              (actl & SCSW_ACTL_SUSP))) {
1655             s->ctrl &= ~SCSW_CTRL_MASK_FCTL;
1656         }
1657         if (stctl != (SCSW_STCTL_INTERMEDIATE | SCSW_STCTL_STATUS_PEND)) {
1658             s->flags &= ~SCSW_FLAGS_MASK_PNO;
1659             s->ctrl &= ~(SCSW_ACTL_RESUME_PEND |
1660                          SCSW_ACTL_START_PEND |
1661                          SCSW_ACTL_HALT_PEND |
1662                          SCSW_ACTL_CLEAR_PEND |
1663                          SCSW_ACTL_SUSP);
1664         } else {
1665             if ((actl & SCSW_ACTL_SUSP) &&
1666                 (fctl & SCSW_FCTL_START_FUNC)) {
1667                 s->flags &= ~SCSW_FLAGS_MASK_PNO;
1668                 if (fctl & SCSW_FCTL_HALT_FUNC) {
1669                     s->ctrl &= ~(SCSW_ACTL_RESUME_PEND |
1670                                  SCSW_ACTL_START_PEND |
1671                                  SCSW_ACTL_HALT_PEND |
1672                                  SCSW_ACTL_CLEAR_PEND |
1673                                  SCSW_ACTL_SUSP);
1674                 } else {
1675                     s->ctrl &= ~SCSW_ACTL_RESUME_PEND;
1676                 }
1677             }
1678         }
1679         /* Clear pending sense data. */
1680         if (p->chars & PMCW_CHARS_MASK_CSENSE) {
1681             memset(sch->sense_data, 0 , sizeof(sch->sense_data));
1682         }
1683     }
1684 }
1685 
1686 static void copy_crw_to_guest(CRW *dest, const CRW *src)
1687 {
1688     dest->flags = cpu_to_be16(src->flags);
1689     dest->rsid = cpu_to_be16(src->rsid);
1690 }
1691 
1692 int css_do_stcrw(CRW *crw)
1693 {
1694     CrwContainer *crw_cont;
1695     int ret;
1696 
1697     crw_cont = QTAILQ_FIRST(&channel_subsys.pending_crws);
1698     if (crw_cont) {
1699         QTAILQ_REMOVE(&channel_subsys.pending_crws, crw_cont, sibling);
1700         copy_crw_to_guest(crw, &crw_cont->crw);
1701         g_free(crw_cont);
1702         ret = 0;
1703     } else {
1704         /* List was empty, turn crw machine checks on again. */
1705         memset(crw, 0, sizeof(*crw));
1706         channel_subsys.do_crw_mchk = true;
1707         ret = 1;
1708     }
1709 
1710     return ret;
1711 }
1712 
1713 static void copy_crw_from_guest(CRW *dest, const CRW *src)
1714 {
1715     dest->flags = be16_to_cpu(src->flags);
1716     dest->rsid = be16_to_cpu(src->rsid);
1717 }
1718 
1719 void css_undo_stcrw(CRW *crw)
1720 {
1721     CrwContainer *crw_cont;
1722 
1723     crw_cont = g_try_new0(CrwContainer, 1);
1724     if (!crw_cont) {
1725         channel_subsys.crws_lost = true;
1726         return;
1727     }
1728     copy_crw_from_guest(&crw_cont->crw, crw);
1729 
1730     QTAILQ_INSERT_HEAD(&channel_subsys.pending_crws, crw_cont, sibling);
1731 }
1732 
1733 int css_collect_chp_desc(int m, uint8_t cssid, uint8_t f_chpid, uint8_t l_chpid,
1734                          int rfmt, void *buf)
1735 {
1736     int i, desc_size;
1737     uint32_t words[8];
1738     uint32_t chpid_type_word;
1739     CssImage *css;
1740 
1741     if (!m && !cssid) {
1742         css = channel_subsys.css[channel_subsys.default_cssid];
1743     } else {
1744         css = channel_subsys.css[cssid];
1745     }
1746     if (!css) {
1747         return 0;
1748     }
1749     desc_size = 0;
1750     for (i = f_chpid; i <= l_chpid; i++) {
1751         if (css->chpids[i].in_use) {
1752             chpid_type_word = 0x80000000 | (css->chpids[i].type << 8) | i;
1753             if (rfmt == 0) {
1754                 words[0] = cpu_to_be32(chpid_type_word);
1755                 words[1] = 0;
1756                 memcpy(buf + desc_size, words, 8);
1757                 desc_size += 8;
1758             } else if (rfmt == 1) {
1759                 words[0] = cpu_to_be32(chpid_type_word);
1760                 words[1] = 0;
1761                 words[2] = 0;
1762                 words[3] = 0;
1763                 words[4] = 0;
1764                 words[5] = 0;
1765                 words[6] = 0;
1766                 words[7] = 0;
1767                 memcpy(buf + desc_size, words, 32);
1768                 desc_size += 32;
1769             }
1770         }
1771     }
1772     return desc_size;
1773 }
1774 
1775 void css_do_schm(uint8_t mbk, int update, int dct, uint64_t mbo)
1776 {
1777     /* dct is currently ignored (not really meaningful for our devices) */
1778     /* TODO: Don't ignore mbk. */
1779     if (update && !channel_subsys.chnmon_active) {
1780         /* Enable measuring. */
1781         channel_subsys.chnmon_area = mbo;
1782         channel_subsys.chnmon_active = true;
1783     }
1784     if (!update && channel_subsys.chnmon_active) {
1785         /* Disable measuring. */
1786         channel_subsys.chnmon_area = 0;
1787         channel_subsys.chnmon_active = false;
1788     }
1789 }
1790 
1791 IOInstEnding css_do_rsch(SubchDev *sch)
1792 {
1793     SCSW *s = &sch->curr_status.scsw;
1794     PMCW *p = &sch->curr_status.pmcw;
1795 
1796     if (~(p->flags) & (PMCW_FLAGS_MASK_DNV | PMCW_FLAGS_MASK_ENA)) {
1797         return IOINST_CC_NOT_OPERATIONAL;
1798     }
1799 
1800     if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
1801         return IOINST_CC_STATUS_PRESENT;
1802     }
1803 
1804     if (((s->ctrl & SCSW_CTRL_MASK_FCTL) != SCSW_FCTL_START_FUNC) ||
1805         (s->ctrl & SCSW_ACTL_RESUME_PEND) ||
1806         (!(s->ctrl & SCSW_ACTL_SUSP))) {
1807         return IOINST_CC_BUSY;
1808     }
1809 
1810     /* If monitoring is active, update counter. */
1811     if (channel_subsys.chnmon_active) {
1812         css_update_chnmon(sch);
1813     }
1814 
1815     s->ctrl |= SCSW_ACTL_RESUME_PEND;
1816     return do_subchannel_work(sch);
1817 }
1818 
1819 int css_do_rchp(uint8_t cssid, uint8_t chpid)
1820 {
1821     uint8_t real_cssid;
1822 
1823     if (cssid > channel_subsys.max_cssid) {
1824         return -EINVAL;
1825     }
1826     if (channel_subsys.max_cssid == 0) {
1827         real_cssid = channel_subsys.default_cssid;
1828     } else {
1829         real_cssid = cssid;
1830     }
1831     if (!channel_subsys.css[real_cssid]) {
1832         return -EINVAL;
1833     }
1834 
1835     if (!channel_subsys.css[real_cssid]->chpids[chpid].in_use) {
1836         return -ENODEV;
1837     }
1838 
1839     if (!channel_subsys.css[real_cssid]->chpids[chpid].is_virtual) {
1840         fprintf(stderr,
1841                 "rchp unsupported for non-virtual chpid %x.%02x!\n",
1842                 real_cssid, chpid);
1843         return -ENODEV;
1844     }
1845 
1846     /* We don't really use a channel path, so we're done here. */
1847     css_queue_crw(CRW_RSC_CHP, CRW_ERC_INIT, 1,
1848                   channel_subsys.max_cssid > 0 ? 1 : 0, chpid);
1849     if (channel_subsys.max_cssid > 0) {
1850         css_queue_crw(CRW_RSC_CHP, CRW_ERC_INIT, 1, 0, real_cssid << 8);
1851     }
1852     return 0;
1853 }
1854 
1855 bool css_schid_final(int m, uint8_t cssid, uint8_t ssid, uint16_t schid)
1856 {
1857     SubchSet *set;
1858     uint8_t real_cssid;
1859 
1860     real_cssid = (!m && (cssid == 0)) ? channel_subsys.default_cssid : cssid;
1861     if (ssid > MAX_SSID ||
1862         !channel_subsys.css[real_cssid] ||
1863         !channel_subsys.css[real_cssid]->sch_set[ssid]) {
1864         return true;
1865     }
1866     set = channel_subsys.css[real_cssid]->sch_set[ssid];
1867     return schid > find_last_bit(set->schids_used,
1868                                  (MAX_SCHID + 1) / sizeof(unsigned long));
1869 }
1870 
1871 unsigned int css_find_free_chpid(uint8_t cssid)
1872 {
1873     CssImage *css = channel_subsys.css[cssid];
1874     unsigned int chpid;
1875 
1876     if (!css) {
1877         return MAX_CHPID + 1;
1878     }
1879 
1880     for (chpid = 0; chpid <= MAX_CHPID; chpid++) {
1881         /* skip reserved chpid */
1882         if (chpid == VIRTIO_CCW_CHPID) {
1883             continue;
1884         }
1885         if (!css->chpids[chpid].in_use) {
1886             return chpid;
1887         }
1888     }
1889     return MAX_CHPID + 1;
1890 }
1891 
1892 static int css_add_chpid(uint8_t cssid, uint8_t chpid, uint8_t type,
1893                          bool is_virt)
1894 {
1895     CssImage *css;
1896 
1897     trace_css_chpid_add(cssid, chpid, type);
1898     css = channel_subsys.css[cssid];
1899     if (!css) {
1900         return -EINVAL;
1901     }
1902     if (css->chpids[chpid].in_use) {
1903         return -EEXIST;
1904     }
1905     css->chpids[chpid].in_use = 1;
1906     css->chpids[chpid].type = type;
1907     css->chpids[chpid].is_virtual = is_virt;
1908 
1909     css_generate_chp_crws(cssid, chpid);
1910 
1911     return 0;
1912 }
1913 
1914 void css_sch_build_virtual_schib(SubchDev *sch, uint8_t chpid, uint8_t type)
1915 {
1916     PMCW *p = &sch->curr_status.pmcw;
1917     SCSW *s = &sch->curr_status.scsw;
1918     int i;
1919     CssImage *css = channel_subsys.css[sch->cssid];
1920 
1921     assert(css != NULL);
1922     memset(p, 0, sizeof(PMCW));
1923     p->flags |= PMCW_FLAGS_MASK_DNV;
1924     p->devno = sch->devno;
1925     /* single path */
1926     p->pim = 0x80;
1927     p->pom = 0xff;
1928     p->pam = 0x80;
1929     p->chpid[0] = chpid;
1930     if (!css->chpids[chpid].in_use) {
1931         css_add_chpid(sch->cssid, chpid, type, true);
1932     }
1933 
1934     memset(s, 0, sizeof(SCSW));
1935     sch->curr_status.mba = 0;
1936     for (i = 0; i < ARRAY_SIZE(sch->curr_status.mda); i++) {
1937         sch->curr_status.mda[i] = 0;
1938     }
1939 }
1940 
1941 SubchDev *css_find_subch(uint8_t m, uint8_t cssid, uint8_t ssid, uint16_t schid)
1942 {
1943     uint8_t real_cssid;
1944 
1945     real_cssid = (!m && (cssid == 0)) ? channel_subsys.default_cssid : cssid;
1946 
1947     if (!channel_subsys.css[real_cssid]) {
1948         return NULL;
1949     }
1950 
1951     if (!channel_subsys.css[real_cssid]->sch_set[ssid]) {
1952         return NULL;
1953     }
1954 
1955     return channel_subsys.css[real_cssid]->sch_set[ssid]->sch[schid];
1956 }
1957 
1958 /**
1959  * Return free device number in subchannel set.
1960  *
1961  * Return index of the first free device number in the subchannel set
1962  * identified by @p cssid and @p ssid, beginning the search at @p
1963  * start and wrapping around at MAX_DEVNO. Return a value exceeding
1964  * MAX_SCHID if there are no free device numbers in the subchannel
1965  * set.
1966  */
1967 static uint32_t css_find_free_devno(uint8_t cssid, uint8_t ssid,
1968                                     uint16_t start)
1969 {
1970     uint32_t round;
1971 
1972     for (round = 0; round <= MAX_DEVNO; round++) {
1973         uint16_t devno = (start + round) % MAX_DEVNO;
1974 
1975         if (!css_devno_used(cssid, ssid, devno)) {
1976             return devno;
1977         }
1978     }
1979     return MAX_DEVNO + 1;
1980 }
1981 
1982 /**
1983  * Return first free subchannel (id) in subchannel set.
1984  *
1985  * Return index of the first free subchannel in the subchannel set
1986  * identified by @p cssid and @p ssid, if there is any. Return a value
1987  * exceeding MAX_SCHID if there are no free subchannels in the
1988  * subchannel set.
1989  */
1990 static uint32_t css_find_free_subch(uint8_t cssid, uint8_t ssid)
1991 {
1992     uint32_t schid;
1993 
1994     for (schid = 0; schid <= MAX_SCHID; schid++) {
1995         if (!css_find_subch(1, cssid, ssid, schid)) {
1996             return schid;
1997         }
1998     }
1999     return MAX_SCHID + 1;
2000 }
2001 
2002 /**
2003  * Return first free subchannel (id) in subchannel set for a device number
2004  *
2005  * Verify the device number @p devno is not used yet in the subchannel
2006  * set identified by @p cssid and @p ssid. Set @p schid to the index
2007  * of the first free subchannel in the subchannel set, if there is
2008  * any. Return true if everything succeeded and false otherwise.
2009  */
2010 static bool css_find_free_subch_for_devno(uint8_t cssid, uint8_t ssid,
2011                                           uint16_t devno, uint16_t *schid,
2012                                           Error **errp)
2013 {
2014     uint32_t free_schid;
2015 
2016     assert(schid);
2017     if (css_devno_used(cssid, ssid, devno)) {
2018         error_setg(errp, "Device %x.%x.%04x already exists",
2019                    cssid, ssid, devno);
2020         return false;
2021     }
2022     free_schid = css_find_free_subch(cssid, ssid);
2023     if (free_schid > MAX_SCHID) {
2024         error_setg(errp, "No free subchannel found for %x.%x.%04x",
2025                    cssid, ssid, devno);
2026         return false;
2027     }
2028     *schid = free_schid;
2029     return true;
2030 }
2031 
2032 /**
2033  * Return first free subchannel (id) and device number
2034  *
2035  * Locate the first free subchannel and first free device number in
2036  * any of the subchannel sets of the channel subsystem identified by
2037  * @p cssid. Return false if no free subchannel / device number could
2038  * be found. Otherwise set @p ssid, @p devno and @p schid to identify
2039  * the available subchannel and device number and return true.
2040  *
2041  * May modify @p ssid, @p devno and / or @p schid even if no free
2042  * subchannel / device number could be found.
2043  */
2044 static bool css_find_free_subch_and_devno(uint8_t cssid, uint8_t *ssid,
2045                                           uint16_t *devno, uint16_t *schid,
2046                                           Error **errp)
2047 {
2048     uint32_t free_schid, free_devno;
2049 
2050     assert(ssid && devno && schid);
2051     for (*ssid = 0; *ssid <= MAX_SSID; (*ssid)++) {
2052         free_schid = css_find_free_subch(cssid, *ssid);
2053         if (free_schid > MAX_SCHID) {
2054             continue;
2055         }
2056         free_devno = css_find_free_devno(cssid, *ssid, free_schid);
2057         if (free_devno > MAX_DEVNO) {
2058             continue;
2059         }
2060         *schid = free_schid;
2061         *devno = free_devno;
2062         return true;
2063     }
2064     error_setg(errp, "Virtual channel subsystem is full!");
2065     return false;
2066 }
2067 
2068 bool css_subch_visible(SubchDev *sch)
2069 {
2070     if (sch->ssid > channel_subsys.max_ssid) {
2071         return false;
2072     }
2073 
2074     if (sch->cssid != channel_subsys.default_cssid) {
2075         return (channel_subsys.max_cssid > 0);
2076     }
2077 
2078     return true;
2079 }
2080 
2081 bool css_present(uint8_t cssid)
2082 {
2083     return (channel_subsys.css[cssid] != NULL);
2084 }
2085 
2086 bool css_devno_used(uint8_t cssid, uint8_t ssid, uint16_t devno)
2087 {
2088     if (!channel_subsys.css[cssid]) {
2089         return false;
2090     }
2091     if (!channel_subsys.css[cssid]->sch_set[ssid]) {
2092         return false;
2093     }
2094 
2095     return !!test_bit(devno,
2096                       channel_subsys.css[cssid]->sch_set[ssid]->devnos_used);
2097 }
2098 
2099 void css_subch_assign(uint8_t cssid, uint8_t ssid, uint16_t schid,
2100                       uint16_t devno, SubchDev *sch)
2101 {
2102     CssImage *css;
2103     SubchSet *s_set;
2104 
2105     trace_css_assign_subch(sch ? "assign" : "deassign", cssid, ssid, schid,
2106                            devno);
2107     if (!channel_subsys.css[cssid]) {
2108         fprintf(stderr,
2109                 "Suspicious call to %s (%x.%x.%04x) for non-existing css!\n",
2110                 __func__, cssid, ssid, schid);
2111         return;
2112     }
2113     css = channel_subsys.css[cssid];
2114 
2115     if (!css->sch_set[ssid]) {
2116         css->sch_set[ssid] = g_new0(SubchSet, 1);
2117     }
2118     s_set = css->sch_set[ssid];
2119 
2120     s_set->sch[schid] = sch;
2121     if (sch) {
2122         set_bit(schid, s_set->schids_used);
2123         set_bit(devno, s_set->devnos_used);
2124     } else {
2125         clear_bit(schid, s_set->schids_used);
2126         clear_bit(devno, s_set->devnos_used);
2127     }
2128 }
2129 
2130 void css_queue_crw(uint8_t rsc, uint8_t erc, int solicited,
2131                    int chain, uint16_t rsid)
2132 {
2133     CrwContainer *crw_cont;
2134 
2135     trace_css_crw(rsc, erc, rsid, chain ? "(chained)" : "");
2136     /* TODO: Maybe use a static crw pool? */
2137     crw_cont = g_try_new0(CrwContainer, 1);
2138     if (!crw_cont) {
2139         channel_subsys.crws_lost = true;
2140         return;
2141     }
2142     crw_cont->crw.flags = (rsc << 8) | erc;
2143     if (solicited) {
2144         crw_cont->crw.flags |= CRW_FLAGS_MASK_S;
2145     }
2146     if (chain) {
2147         crw_cont->crw.flags |= CRW_FLAGS_MASK_C;
2148     }
2149     crw_cont->crw.rsid = rsid;
2150     if (channel_subsys.crws_lost) {
2151         crw_cont->crw.flags |= CRW_FLAGS_MASK_R;
2152         channel_subsys.crws_lost = false;
2153     }
2154 
2155     QTAILQ_INSERT_TAIL(&channel_subsys.pending_crws, crw_cont, sibling);
2156 
2157     if (channel_subsys.do_crw_mchk) {
2158         channel_subsys.do_crw_mchk = false;
2159         /* Inject crw pending machine check. */
2160         s390_crw_mchk();
2161     }
2162 }
2163 
2164 void css_generate_sch_crws(uint8_t cssid, uint8_t ssid, uint16_t schid,
2165                            int hotplugged, int add)
2166 {
2167     uint8_t guest_cssid;
2168     bool chain_crw;
2169 
2170     if (add && !hotplugged) {
2171         return;
2172     }
2173     if (channel_subsys.max_cssid == 0) {
2174         /* Default cssid shows up as 0. */
2175         guest_cssid = (cssid == channel_subsys.default_cssid) ? 0 : cssid;
2176     } else {
2177         /* Show real cssid to the guest. */
2178         guest_cssid = cssid;
2179     }
2180     /*
2181      * Only notify for higher subchannel sets/channel subsystems if the
2182      * guest has enabled it.
2183      */
2184     if ((ssid > channel_subsys.max_ssid) ||
2185         (guest_cssid > channel_subsys.max_cssid) ||
2186         ((channel_subsys.max_cssid == 0) &&
2187          (cssid != channel_subsys.default_cssid))) {
2188         return;
2189     }
2190     chain_crw = (channel_subsys.max_ssid > 0) ||
2191             (channel_subsys.max_cssid > 0);
2192     css_queue_crw(CRW_RSC_SUBCH, CRW_ERC_IPI, 0, chain_crw ? 1 : 0, schid);
2193     if (chain_crw) {
2194         css_queue_crw(CRW_RSC_SUBCH, CRW_ERC_IPI, 0, 0,
2195                       (guest_cssid << 8) | (ssid << 4));
2196     }
2197     /* RW_ERC_IPI --> clear pending interrupts */
2198     css_clear_io_interrupt(css_do_build_subchannel_id(cssid, ssid), schid);
2199 }
2200 
2201 void css_generate_chp_crws(uint8_t cssid, uint8_t chpid)
2202 {
2203     /* TODO */
2204 }
2205 
2206 void css_generate_css_crws(uint8_t cssid)
2207 {
2208     if (!channel_subsys.sei_pending) {
2209         css_queue_crw(CRW_RSC_CSS, CRW_ERC_EVENT, 0, 0, cssid);
2210     }
2211     channel_subsys.sei_pending = true;
2212 }
2213 
2214 void css_clear_sei_pending(void)
2215 {
2216     channel_subsys.sei_pending = false;
2217 }
2218 
2219 int css_enable_mcsse(void)
2220 {
2221     trace_css_enable_facility("mcsse");
2222     channel_subsys.max_cssid = MAX_CSSID;
2223     return 0;
2224 }
2225 
2226 int css_enable_mss(void)
2227 {
2228     trace_css_enable_facility("mss");
2229     channel_subsys.max_ssid = MAX_SSID;
2230     return 0;
2231 }
2232 
2233 void css_reset_sch(SubchDev *sch)
2234 {
2235     PMCW *p = &sch->curr_status.pmcw;
2236 
2237     if ((p->flags & PMCW_FLAGS_MASK_ENA) != 0 && sch->disable_cb) {
2238         sch->disable_cb(sch);
2239     }
2240 
2241     p->intparm = 0;
2242     p->flags &= ~(PMCW_FLAGS_MASK_ISC | PMCW_FLAGS_MASK_ENA |
2243                   PMCW_FLAGS_MASK_LM | PMCW_FLAGS_MASK_MME |
2244                   PMCW_FLAGS_MASK_MP | PMCW_FLAGS_MASK_TF);
2245     p->flags |= PMCW_FLAGS_MASK_DNV;
2246     p->devno = sch->devno;
2247     p->pim = 0x80;
2248     p->lpm = p->pim;
2249     p->pnom = 0;
2250     p->lpum = 0;
2251     p->mbi = 0;
2252     p->pom = 0xff;
2253     p->pam = 0x80;
2254     p->chars &= ~(PMCW_CHARS_MASK_MBFC | PMCW_CHARS_MASK_XMWME |
2255                   PMCW_CHARS_MASK_CSENSE);
2256 
2257     memset(&sch->curr_status.scsw, 0, sizeof(sch->curr_status.scsw));
2258     sch->curr_status.mba = 0;
2259 
2260     sch->channel_prog = 0x0;
2261     sch->last_cmd_valid = false;
2262     sch->thinint_active = false;
2263 }
2264 
2265 void css_reset(void)
2266 {
2267     CrwContainer *crw_cont;
2268 
2269     /* Clean up monitoring. */
2270     channel_subsys.chnmon_active = false;
2271     channel_subsys.chnmon_area = 0;
2272 
2273     /* Clear pending CRWs. */
2274     while ((crw_cont = QTAILQ_FIRST(&channel_subsys.pending_crws))) {
2275         QTAILQ_REMOVE(&channel_subsys.pending_crws, crw_cont, sibling);
2276         g_free(crw_cont);
2277     }
2278     channel_subsys.sei_pending = false;
2279     channel_subsys.do_crw_mchk = true;
2280     channel_subsys.crws_lost = false;
2281 
2282     /* Reset maximum ids. */
2283     channel_subsys.max_cssid = 0;
2284     channel_subsys.max_ssid = 0;
2285 }
2286 
2287 static void get_css_devid(Object *obj, Visitor *v, const char *name,
2288                           void *opaque, Error **errp)
2289 {
2290     DeviceState *dev = DEVICE(obj);
2291     Property *prop = opaque;
2292     CssDevId *dev_id = qdev_get_prop_ptr(dev, prop);
2293     char buffer[] = "xx.x.xxxx";
2294     char *p = buffer;
2295     int r;
2296 
2297     if (dev_id->valid) {
2298 
2299         r = snprintf(buffer, sizeof(buffer), "%02x.%1x.%04x", dev_id->cssid,
2300                      dev_id->ssid, dev_id->devid);
2301         assert(r == sizeof(buffer) - 1);
2302 
2303         /* drop leading zero */
2304         if (dev_id->cssid <= 0xf) {
2305             p++;
2306         }
2307     } else {
2308         snprintf(buffer, sizeof(buffer), "<unset>");
2309     }
2310 
2311     visit_type_str(v, name, &p, errp);
2312 }
2313 
2314 /*
2315  * parse <cssid>.<ssid>.<devid> and assert valid range for cssid/ssid
2316  */
2317 static void set_css_devid(Object *obj, Visitor *v, const char *name,
2318                           void *opaque, Error **errp)
2319 {
2320     DeviceState *dev = DEVICE(obj);
2321     Property *prop = opaque;
2322     CssDevId *dev_id = qdev_get_prop_ptr(dev, prop);
2323     Error *local_err = NULL;
2324     char *str;
2325     int num, n1, n2;
2326     unsigned int cssid, ssid, devid;
2327 
2328     if (dev->realized) {
2329         qdev_prop_set_after_realize(dev, name, errp);
2330         return;
2331     }
2332 
2333     visit_type_str(v, name, &str, &local_err);
2334     if (local_err) {
2335         error_propagate(errp, local_err);
2336         return;
2337     }
2338 
2339     num = sscanf(str, "%2x.%1x%n.%4x%n", &cssid, &ssid, &n1, &devid, &n2);
2340     if (num != 3 || (n2 - n1) != 5 || strlen(str) != n2) {
2341         error_set_from_qdev_prop_error(errp, EINVAL, dev, prop, str);
2342         goto out;
2343     }
2344     if ((cssid > MAX_CSSID) || (ssid > MAX_SSID)) {
2345         error_setg(errp, "Invalid cssid or ssid: cssid %x, ssid %x",
2346                    cssid, ssid);
2347         goto out;
2348     }
2349 
2350     dev_id->cssid = cssid;
2351     dev_id->ssid = ssid;
2352     dev_id->devid = devid;
2353     dev_id->valid = true;
2354 
2355 out:
2356     g_free(str);
2357 }
2358 
2359 const PropertyInfo css_devid_propinfo = {
2360     .name = "str",
2361     .description = "Identifier of an I/O device in the channel "
2362                    "subsystem, example: fe.1.23ab",
2363     .get = get_css_devid,
2364     .set = set_css_devid,
2365 };
2366 
2367 const PropertyInfo css_devid_ro_propinfo = {
2368     .name = "str",
2369     .description = "Read-only identifier of an I/O device in the channel "
2370                    "subsystem, example: fe.1.23ab",
2371     .get = get_css_devid,
2372 };
2373 
2374 SubchDev *css_create_sch(CssDevId bus_id, bool squash_mcss, Error **errp)
2375 {
2376     uint16_t schid = 0;
2377     SubchDev *sch;
2378 
2379     if (bus_id.valid) {
2380         if (squash_mcss) {
2381             bus_id.cssid = channel_subsys.default_cssid;
2382         } else if (!channel_subsys.css[bus_id.cssid]) {
2383             css_create_css_image(bus_id.cssid, false);
2384         }
2385 
2386         if (!css_find_free_subch_for_devno(bus_id.cssid, bus_id.ssid,
2387                                            bus_id.devid, &schid, errp)) {
2388             return NULL;
2389         }
2390     } else {
2391         for (bus_id.cssid = channel_subsys.default_cssid;;) {
2392             if (!channel_subsys.css[bus_id.cssid]) {
2393                 css_create_css_image(bus_id.cssid, false);
2394             }
2395 
2396             if   (css_find_free_subch_and_devno(bus_id.cssid, &bus_id.ssid,
2397                                                 &bus_id.devid, &schid,
2398                                                 NULL)) {
2399                 break;
2400             }
2401             bus_id.cssid = (bus_id.cssid + 1) % MAX_CSSID;
2402             if (bus_id.cssid == channel_subsys.default_cssid) {
2403                 error_setg(errp, "Virtual channel subsystem is full!");
2404                 return NULL;
2405             }
2406         }
2407     }
2408 
2409     sch = g_new0(SubchDev, 1);
2410     sch->cssid = bus_id.cssid;
2411     sch->ssid = bus_id.ssid;
2412     sch->devno = bus_id.devid;
2413     sch->schid = schid;
2414     css_subch_assign(sch->cssid, sch->ssid, schid, sch->devno, sch);
2415     return sch;
2416 }
2417 
2418 static int css_sch_get_chpids(SubchDev *sch, CssDevId *dev_id)
2419 {
2420     char *fid_path;
2421     FILE *fd;
2422     uint32_t chpid[8];
2423     int i;
2424     PMCW *p = &sch->curr_status.pmcw;
2425 
2426     fid_path = g_strdup_printf("/sys/bus/css/devices/%x.%x.%04x/chpids",
2427                                dev_id->cssid, dev_id->ssid, dev_id->devid);
2428     fd = fopen(fid_path, "r");
2429     if (fd == NULL) {
2430         error_report("%s: open %s failed", __func__, fid_path);
2431         g_free(fid_path);
2432         return -EINVAL;
2433     }
2434 
2435     if (fscanf(fd, "%x %x %x %x %x %x %x %x",
2436         &chpid[0], &chpid[1], &chpid[2], &chpid[3],
2437         &chpid[4], &chpid[5], &chpid[6], &chpid[7]) != 8) {
2438         fclose(fd);
2439         g_free(fid_path);
2440         return -EINVAL;
2441     }
2442 
2443     for (i = 0; i < ARRAY_SIZE(p->chpid); i++) {
2444         p->chpid[i] = chpid[i];
2445     }
2446 
2447     fclose(fd);
2448     g_free(fid_path);
2449 
2450     return 0;
2451 }
2452 
2453 static int css_sch_get_path_masks(SubchDev *sch, CssDevId *dev_id)
2454 {
2455     char *fid_path;
2456     FILE *fd;
2457     uint32_t pim, pam, pom;
2458     PMCW *p = &sch->curr_status.pmcw;
2459 
2460     fid_path = g_strdup_printf("/sys/bus/css/devices/%x.%x.%04x/pimpampom",
2461                                dev_id->cssid, dev_id->ssid, dev_id->devid);
2462     fd = fopen(fid_path, "r");
2463     if (fd == NULL) {
2464         error_report("%s: open %s failed", __func__, fid_path);
2465         g_free(fid_path);
2466         return -EINVAL;
2467     }
2468 
2469     if (fscanf(fd, "%x %x %x", &pim, &pam, &pom) != 3) {
2470         fclose(fd);
2471         g_free(fid_path);
2472         return -EINVAL;
2473     }
2474 
2475     p->pim = pim;
2476     p->pam = pam;
2477     p->pom = pom;
2478     fclose(fd);
2479     g_free(fid_path);
2480 
2481     return 0;
2482 }
2483 
2484 static int css_sch_get_chpid_type(uint8_t chpid, uint32_t *type,
2485                                   CssDevId *dev_id)
2486 {
2487     char *fid_path;
2488     FILE *fd;
2489 
2490     fid_path = g_strdup_printf("/sys/devices/css%x/chp0.%02x/type",
2491                                dev_id->cssid, chpid);
2492     fd = fopen(fid_path, "r");
2493     if (fd == NULL) {
2494         error_report("%s: open %s failed", __func__, fid_path);
2495         g_free(fid_path);
2496         return -EINVAL;
2497     }
2498 
2499     if (fscanf(fd, "%x", type) != 1) {
2500         fclose(fd);
2501         g_free(fid_path);
2502         return -EINVAL;
2503     }
2504 
2505     fclose(fd);
2506     g_free(fid_path);
2507 
2508     return 0;
2509 }
2510 
2511 /*
2512  * We currently retrieve the real device information from sysfs to build the
2513  * guest subchannel information block without considering the migration feature.
2514  * We need to revisit this problem when we want to add migration support.
2515  */
2516 int css_sch_build_schib(SubchDev *sch, CssDevId *dev_id)
2517 {
2518     CssImage *css = channel_subsys.css[sch->cssid];
2519     PMCW *p = &sch->curr_status.pmcw;
2520     SCSW *s = &sch->curr_status.scsw;
2521     uint32_t type;
2522     int i, ret;
2523 
2524     assert(css != NULL);
2525     memset(p, 0, sizeof(PMCW));
2526     p->flags |= PMCW_FLAGS_MASK_DNV;
2527     /* We are dealing with I/O subchannels only. */
2528     p->devno = sch->devno;
2529 
2530     /* Grab path mask from sysfs. */
2531     ret = css_sch_get_path_masks(sch, dev_id);
2532     if (ret) {
2533         return ret;
2534     }
2535 
2536     /* Grab chpids from sysfs. */
2537     ret = css_sch_get_chpids(sch, dev_id);
2538     if (ret) {
2539         return ret;
2540     }
2541 
2542    /* Build chpid type. */
2543     for (i = 0; i < ARRAY_SIZE(p->chpid); i++) {
2544         if (p->chpid[i] && !css->chpids[p->chpid[i]].in_use) {
2545             ret = css_sch_get_chpid_type(p->chpid[i], &type, dev_id);
2546             if (ret) {
2547                 return ret;
2548             }
2549             css_add_chpid(sch->cssid, p->chpid[i], type, false);
2550         }
2551     }
2552 
2553     memset(s, 0, sizeof(SCSW));
2554     sch->curr_status.mba = 0;
2555     for (i = 0; i < ARRAY_SIZE(sch->curr_status.mda); i++) {
2556         sch->curr_status.mda[i] = 0;
2557     }
2558 
2559     return 0;
2560 }
2561