xref: /openbmc/qemu/hw/s390x/virtio-ccw.c (revision ddda3748)
1 /*
2  * virtio ccw target implementation
3  *
4  * Copyright 2012,2015 IBM Corp.
5  * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
6  *            Pierre Morel <pmorel@linux.vnet.ibm.com>
7  *
8  * This work is licensed under the terms of the GNU GPL, version 2 or (at
9  * your option) any later version. See the COPYING file in the top-level
10  * directory.
11  */
12 
13 #include "qemu/osdep.h"
14 #include "qapi/error.h"
15 #include "sysemu/kvm.h"
16 #include "net/net.h"
17 #include "hw/virtio/virtio.h"
18 #include "migration/qemu-file-types.h"
19 #include "hw/virtio/virtio-net.h"
20 #include "hw/sysbus.h"
21 #include "qemu/bitops.h"
22 #include "qemu/error-report.h"
23 #include "qemu/module.h"
24 #include "hw/virtio/virtio-access.h"
25 #include "hw/virtio/virtio-bus.h"
26 #include "hw/s390x/adapter.h"
27 #include "hw/s390x/s390_flic.h"
28 
29 #include "hw/s390x/ioinst.h"
30 #include "hw/s390x/css.h"
31 #include "virtio-ccw.h"
32 #include "trace.h"
33 #include "hw/s390x/css-bridge.h"
34 #include "hw/s390x/s390-virtio-ccw.h"
35 
36 #define NR_CLASSIC_INDICATOR_BITS 64
37 
38 static int virtio_ccw_dev_post_load(void *opaque, int version_id)
39 {
40     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(opaque);
41     CcwDevice *ccw_dev = CCW_DEVICE(dev);
42     CCWDeviceClass *ck = CCW_DEVICE_GET_CLASS(ccw_dev);
43 
44     ccw_dev->sch->driver_data = dev;
45     if (ccw_dev->sch->thinint_active) {
46         dev->routes.adapter.adapter_id = css_get_adapter_id(
47                                          CSS_IO_ADAPTER_VIRTIO,
48                                          dev->thinint_isc);
49     }
50     /* Re-fill subch_id after loading the subchannel states.*/
51     if (ck->refill_ids) {
52         ck->refill_ids(ccw_dev);
53     }
54     return 0;
55 }
56 
57 typedef struct VirtioCcwDeviceTmp {
58     VirtioCcwDevice *parent;
59     uint16_t config_vector;
60 } VirtioCcwDeviceTmp;
61 
62 static int virtio_ccw_dev_tmp_pre_save(void *opaque)
63 {
64     VirtioCcwDeviceTmp *tmp = opaque;
65     VirtioCcwDevice *dev = tmp->parent;
66     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
67 
68     tmp->config_vector = vdev->config_vector;
69 
70     return 0;
71 }
72 
73 static int virtio_ccw_dev_tmp_post_load(void *opaque, int version_id)
74 {
75     VirtioCcwDeviceTmp *tmp = opaque;
76     VirtioCcwDevice *dev = tmp->parent;
77     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
78 
79     vdev->config_vector = tmp->config_vector;
80     return 0;
81 }
82 
83 const VMStateDescription vmstate_virtio_ccw_dev_tmp = {
84     .name = "s390_virtio_ccw_dev_tmp",
85     .pre_save = virtio_ccw_dev_tmp_pre_save,
86     .post_load = virtio_ccw_dev_tmp_post_load,
87     .fields = (VMStateField[]) {
88         VMSTATE_UINT16(config_vector, VirtioCcwDeviceTmp),
89         VMSTATE_END_OF_LIST()
90     }
91 };
92 
93 const VMStateDescription vmstate_virtio_ccw_dev = {
94     .name = "s390_virtio_ccw_dev",
95     .version_id = 1,
96     .minimum_version_id = 1,
97     .post_load = virtio_ccw_dev_post_load,
98     .fields = (VMStateField[]) {
99         VMSTATE_CCW_DEVICE(parent_obj, VirtioCcwDevice),
100         VMSTATE_PTR_TO_IND_ADDR(indicators, VirtioCcwDevice),
101         VMSTATE_PTR_TO_IND_ADDR(indicators2, VirtioCcwDevice),
102         VMSTATE_PTR_TO_IND_ADDR(summary_indicator, VirtioCcwDevice),
103         /*
104          * Ugly hack because VirtIODevice does not migrate itself.
105          * This also makes legacy via vmstate_save_state possible.
106          */
107         VMSTATE_WITH_TMP(VirtioCcwDevice, VirtioCcwDeviceTmp,
108                          vmstate_virtio_ccw_dev_tmp),
109         VMSTATE_STRUCT(routes, VirtioCcwDevice, 1, vmstate_adapter_routes,
110                        AdapterRoutes),
111         VMSTATE_UINT8(thinint_isc, VirtioCcwDevice),
112         VMSTATE_INT32(revision, VirtioCcwDevice),
113         VMSTATE_END_OF_LIST()
114     }
115 };
116 
117 static void virtio_ccw_bus_new(VirtioBusState *bus, size_t bus_size,
118                                VirtioCcwDevice *dev);
119 
120 VirtIODevice *virtio_ccw_get_vdev(SubchDev *sch)
121 {
122     VirtIODevice *vdev = NULL;
123     VirtioCcwDevice *dev = sch->driver_data;
124 
125     if (dev) {
126         vdev = virtio_bus_get_device(&dev->bus);
127     }
128     return vdev;
129 }
130 
131 static void virtio_ccw_start_ioeventfd(VirtioCcwDevice *dev)
132 {
133     virtio_bus_start_ioeventfd(&dev->bus);
134 }
135 
136 static void virtio_ccw_stop_ioeventfd(VirtioCcwDevice *dev)
137 {
138     virtio_bus_stop_ioeventfd(&dev->bus);
139 }
140 
141 static bool virtio_ccw_ioeventfd_enabled(DeviceState *d)
142 {
143     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
144 
145     return (dev->flags & VIRTIO_CCW_FLAG_USE_IOEVENTFD) != 0;
146 }
147 
148 static int virtio_ccw_ioeventfd_assign(DeviceState *d, EventNotifier *notifier,
149                                        int n, bool assign)
150 {
151     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
152     CcwDevice *ccw_dev = CCW_DEVICE(dev);
153     SubchDev *sch = ccw_dev->sch;
154     uint32_t sch_id = (css_build_subchannel_id(sch) << 16) | sch->schid;
155 
156     return s390_assign_subch_ioeventfd(notifier, sch_id, n, assign);
157 }
158 
159 /* Communication blocks used by several channel commands. */
160 typedef struct VqInfoBlockLegacy {
161     uint64_t queue;
162     uint32_t align;
163     uint16_t index;
164     uint16_t num;
165 } QEMU_PACKED VqInfoBlockLegacy;
166 
167 typedef struct VqInfoBlock {
168     uint64_t desc;
169     uint32_t res0;
170     uint16_t index;
171     uint16_t num;
172     uint64_t avail;
173     uint64_t used;
174 } QEMU_PACKED VqInfoBlock;
175 
176 typedef struct VqConfigBlock {
177     uint16_t index;
178     uint16_t num_max;
179 } QEMU_PACKED VqConfigBlock;
180 
181 typedef struct VirtioFeatDesc {
182     uint32_t features;
183     uint8_t index;
184 } QEMU_PACKED VirtioFeatDesc;
185 
186 typedef struct VirtioThinintInfo {
187     hwaddr summary_indicator;
188     hwaddr device_indicator;
189     uint64_t ind_bit;
190     uint8_t isc;
191 } QEMU_PACKED VirtioThinintInfo;
192 
193 typedef struct VirtioRevInfo {
194     uint16_t revision;
195     uint16_t length;
196     uint8_t data[0];
197 } QEMU_PACKED VirtioRevInfo;
198 
199 /* Specify where the virtqueues for the subchannel are in guest memory. */
200 static int virtio_ccw_set_vqs(SubchDev *sch, VqInfoBlock *info,
201                               VqInfoBlockLegacy *linfo)
202 {
203     VirtIODevice *vdev = virtio_ccw_get_vdev(sch);
204     uint16_t index = info ? info->index : linfo->index;
205     uint16_t num = info ? info->num : linfo->num;
206     uint64_t desc = info ? info->desc : linfo->queue;
207 
208     if (index >= VIRTIO_QUEUE_MAX) {
209         return -EINVAL;
210     }
211 
212     /* Current code in virtio.c relies on 4K alignment. */
213     if (linfo && desc && (linfo->align != 4096)) {
214         return -EINVAL;
215     }
216 
217     if (!vdev) {
218         return -EINVAL;
219     }
220 
221     if (info) {
222         virtio_queue_set_rings(vdev, index, desc, info->avail, info->used);
223     } else {
224         virtio_queue_set_addr(vdev, index, desc);
225     }
226     if (!desc) {
227         virtio_queue_set_vector(vdev, index, VIRTIO_NO_VECTOR);
228     } else {
229         if (info) {
230             /* virtio-1 allows changing the ring size. */
231             if (virtio_queue_get_max_num(vdev, index) < num) {
232                 /* Fail if we exceed the maximum number. */
233                 return -EINVAL;
234             }
235             virtio_queue_set_num(vdev, index, num);
236         } else if (virtio_queue_get_num(vdev, index) > num) {
237             /* Fail if we don't have a big enough queue. */
238             return -EINVAL;
239         }
240         /* We ignore possible increased num for legacy for compatibility. */
241         virtio_queue_set_vector(vdev, index, index);
242     }
243     /* tell notify handler in case of config change */
244     vdev->config_vector = VIRTIO_QUEUE_MAX;
245     return 0;
246 }
247 
248 static void virtio_ccw_reset_virtio(VirtioCcwDevice *dev, VirtIODevice *vdev)
249 {
250     CcwDevice *ccw_dev = CCW_DEVICE(dev);
251 
252     virtio_ccw_stop_ioeventfd(dev);
253     virtio_reset(vdev);
254     if (dev->indicators) {
255         release_indicator(&dev->routes.adapter, dev->indicators);
256         dev->indicators = NULL;
257     }
258     if (dev->indicators2) {
259         release_indicator(&dev->routes.adapter, dev->indicators2);
260         dev->indicators2 = NULL;
261     }
262     if (dev->summary_indicator) {
263         release_indicator(&dev->routes.adapter, dev->summary_indicator);
264         dev->summary_indicator = NULL;
265     }
266     ccw_dev->sch->thinint_active = false;
267 }
268 
269 static int virtio_ccw_handle_set_vq(SubchDev *sch, CCW1 ccw, bool check_len,
270                                     bool is_legacy)
271 {
272     int ret;
273     VqInfoBlock info;
274     VqInfoBlockLegacy linfo;
275     size_t info_len = is_legacy ? sizeof(linfo) : sizeof(info);
276 
277     if (check_len) {
278         if (ccw.count != info_len) {
279             return -EINVAL;
280         }
281     } else if (ccw.count < info_len) {
282         /* Can't execute command. */
283         return -EINVAL;
284     }
285     if (!ccw.cda) {
286         return -EFAULT;
287     }
288     if (is_legacy) {
289         ccw_dstream_read(&sch->cds, linfo);
290         linfo.queue = be64_to_cpu(linfo.queue);
291         linfo.align = be32_to_cpu(linfo.align);
292         linfo.index = be16_to_cpu(linfo.index);
293         linfo.num = be16_to_cpu(linfo.num);
294         ret = virtio_ccw_set_vqs(sch, NULL, &linfo);
295     } else {
296         ccw_dstream_read(&sch->cds, info);
297         info.desc = be64_to_cpu(info.desc);
298         info.index = be16_to_cpu(info.index);
299         info.num = be16_to_cpu(info.num);
300         info.avail = be64_to_cpu(info.avail);
301         info.used = be64_to_cpu(info.used);
302         ret = virtio_ccw_set_vqs(sch, &info, NULL);
303     }
304     sch->curr_status.scsw.count = 0;
305     return ret;
306 }
307 
308 static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw)
309 {
310     int ret;
311     VirtioRevInfo revinfo;
312     uint8_t status;
313     VirtioFeatDesc features;
314     hwaddr indicators;
315     VqConfigBlock vq_config;
316     VirtioCcwDevice *dev = sch->driver_data;
317     VirtIODevice *vdev = virtio_ccw_get_vdev(sch);
318     bool check_len;
319     int len;
320     VirtioThinintInfo thinint;
321 
322     if (!dev) {
323         return -EINVAL;
324     }
325 
326     trace_virtio_ccw_interpret_ccw(sch->cssid, sch->ssid, sch->schid,
327                                    ccw.cmd_code);
328     check_len = !((ccw.flags & CCW_FLAG_SLI) && !(ccw.flags & CCW_FLAG_DC));
329 
330     if (dev->force_revision_1 && dev->revision < 0 &&
331         ccw.cmd_code != CCW_CMD_SET_VIRTIO_REV) {
332         /*
333          * virtio-1 drivers must start with negotiating to a revision >= 1,
334          * so post a command reject for all other commands
335          */
336         return -ENOSYS;
337     }
338 
339     /* Look at the command. */
340     switch (ccw.cmd_code) {
341     case CCW_CMD_SET_VQ:
342         ret = virtio_ccw_handle_set_vq(sch, ccw, check_len, dev->revision < 1);
343         break;
344     case CCW_CMD_VDEV_RESET:
345         virtio_ccw_reset_virtio(dev, vdev);
346         ret = 0;
347         break;
348     case CCW_CMD_READ_FEAT:
349         if (check_len) {
350             if (ccw.count != sizeof(features)) {
351                 ret = -EINVAL;
352                 break;
353             }
354         } else if (ccw.count < sizeof(features)) {
355             /* Can't execute command. */
356             ret = -EINVAL;
357             break;
358         }
359         if (!ccw.cda) {
360             ret = -EFAULT;
361         } else {
362             VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
363 
364             ccw_dstream_advance(&sch->cds, sizeof(features.features));
365             ccw_dstream_read(&sch->cds, features.index);
366             if (features.index == 0) {
367                 if (dev->revision >= 1) {
368                     /* Don't offer legacy features for modern devices. */
369                     features.features = (uint32_t)
370                         (vdev->host_features & ~vdc->legacy_features);
371                 } else {
372                     features.features = (uint32_t)vdev->host_features;
373                 }
374             } else if ((features.index == 1) && (dev->revision >= 1)) {
375                 /*
376                  * Only offer feature bits beyond 31 if the guest has
377                  * negotiated at least revision 1.
378                  */
379                 features.features = (uint32_t)(vdev->host_features >> 32);
380             } else {
381                 /* Return zeroes if the guest supports more feature bits. */
382                 features.features = 0;
383             }
384             ccw_dstream_rewind(&sch->cds);
385             features.features = cpu_to_le32(features.features);
386             ccw_dstream_write(&sch->cds, features.features);
387             sch->curr_status.scsw.count = ccw.count - sizeof(features);
388             ret = 0;
389         }
390         break;
391     case CCW_CMD_WRITE_FEAT:
392         if (check_len) {
393             if (ccw.count != sizeof(features)) {
394                 ret = -EINVAL;
395                 break;
396             }
397         } else if (ccw.count < sizeof(features)) {
398             /* Can't execute command. */
399             ret = -EINVAL;
400             break;
401         }
402         if (!ccw.cda) {
403             ret = -EFAULT;
404         } else {
405             ccw_dstream_read(&sch->cds, features);
406             features.features = le32_to_cpu(features.features);
407             if (features.index == 0) {
408                 virtio_set_features(vdev,
409                                     (vdev->guest_features & 0xffffffff00000000ULL) |
410                                     features.features);
411             } else if ((features.index == 1) && (dev->revision >= 1)) {
412                 /*
413                  * If the guest did not negotiate at least revision 1,
414                  * we did not offer it any feature bits beyond 31. Such a
415                  * guest passing us any bit here is therefore buggy.
416                  */
417                 virtio_set_features(vdev,
418                                     (vdev->guest_features & 0x00000000ffffffffULL) |
419                                     ((uint64_t)features.features << 32));
420             } else {
421                 /*
422                  * If the guest supports more feature bits, assert that it
423                  * passes us zeroes for those we don't support.
424                  */
425                 if (features.features) {
426                     qemu_log_mask(LOG_GUEST_ERROR,
427                                   "Guest bug: features[%i]=%x (expected 0)",
428                                   features.index, features.features);
429                     /* XXX: do a unit check here? */
430                 }
431             }
432             sch->curr_status.scsw.count = ccw.count - sizeof(features);
433             ret = 0;
434         }
435         break;
436     case CCW_CMD_READ_CONF:
437         if (check_len) {
438             if (ccw.count > vdev->config_len) {
439                 ret = -EINVAL;
440                 break;
441             }
442         }
443         len = MIN(ccw.count, vdev->config_len);
444         if (!ccw.cda) {
445             ret = -EFAULT;
446         } else {
447             virtio_bus_get_vdev_config(&dev->bus, vdev->config);
448             ccw_dstream_write_buf(&sch->cds, vdev->config, len);
449             sch->curr_status.scsw.count = ccw.count - len;
450             ret = 0;
451         }
452         break;
453     case CCW_CMD_WRITE_CONF:
454         if (check_len) {
455             if (ccw.count > vdev->config_len) {
456                 ret = -EINVAL;
457                 break;
458             }
459         }
460         len = MIN(ccw.count, vdev->config_len);
461         if (!ccw.cda) {
462             ret = -EFAULT;
463         } else {
464             ret = ccw_dstream_read_buf(&sch->cds, vdev->config, len);
465             if (!ret) {
466                 virtio_bus_set_vdev_config(&dev->bus, vdev->config);
467                 sch->curr_status.scsw.count = ccw.count - len;
468             }
469         }
470         break;
471     case CCW_CMD_READ_STATUS:
472         if (check_len) {
473             if (ccw.count != sizeof(status)) {
474                 ret = -EINVAL;
475                 break;
476             }
477         } else if (ccw.count < sizeof(status)) {
478             /* Can't execute command. */
479             ret = -EINVAL;
480             break;
481         }
482         if (!ccw.cda) {
483             ret = -EFAULT;
484         } else {
485             address_space_stb(&address_space_memory, ccw.cda, vdev->status,
486                                         MEMTXATTRS_UNSPECIFIED, NULL);
487             sch->curr_status.scsw.count = ccw.count - sizeof(vdev->status);
488             ret = 0;
489         }
490         break;
491     case CCW_CMD_WRITE_STATUS:
492         if (check_len) {
493             if (ccw.count != sizeof(status)) {
494                 ret = -EINVAL;
495                 break;
496             }
497         } else if (ccw.count < sizeof(status)) {
498             /* Can't execute command. */
499             ret = -EINVAL;
500             break;
501         }
502         if (!ccw.cda) {
503             ret = -EFAULT;
504         } else {
505             ccw_dstream_read(&sch->cds, status);
506             if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
507                 virtio_ccw_stop_ioeventfd(dev);
508             }
509             if (virtio_set_status(vdev, status) == 0) {
510                 if (vdev->status == 0) {
511                     virtio_ccw_reset_virtio(dev, vdev);
512                 }
513                 if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
514                     virtio_ccw_start_ioeventfd(dev);
515                 }
516                 sch->curr_status.scsw.count = ccw.count - sizeof(status);
517                 ret = 0;
518             } else {
519                 /* Trigger a command reject. */
520                 ret = -ENOSYS;
521             }
522         }
523         break;
524     case CCW_CMD_SET_IND:
525         if (check_len) {
526             if (ccw.count != sizeof(indicators)) {
527                 ret = -EINVAL;
528                 break;
529             }
530         } else if (ccw.count < sizeof(indicators)) {
531             /* Can't execute command. */
532             ret = -EINVAL;
533             break;
534         }
535         if (sch->thinint_active) {
536             /* Trigger a command reject. */
537             ret = -ENOSYS;
538             break;
539         }
540         if (virtio_get_num_queues(vdev) > NR_CLASSIC_INDICATOR_BITS) {
541             /* More queues than indicator bits --> trigger a reject */
542             ret = -ENOSYS;
543             break;
544         }
545         if (!ccw.cda) {
546             ret = -EFAULT;
547         } else {
548             ccw_dstream_read(&sch->cds, indicators);
549             indicators = be64_to_cpu(indicators);
550             dev->indicators = get_indicator(indicators, sizeof(uint64_t));
551             sch->curr_status.scsw.count = ccw.count - sizeof(indicators);
552             ret = 0;
553         }
554         break;
555     case CCW_CMD_SET_CONF_IND:
556         if (check_len) {
557             if (ccw.count != sizeof(indicators)) {
558                 ret = -EINVAL;
559                 break;
560             }
561         } else if (ccw.count < sizeof(indicators)) {
562             /* Can't execute command. */
563             ret = -EINVAL;
564             break;
565         }
566         if (!ccw.cda) {
567             ret = -EFAULT;
568         } else {
569             ccw_dstream_read(&sch->cds, indicators);
570             indicators = be64_to_cpu(indicators);
571             dev->indicators2 = get_indicator(indicators, sizeof(uint64_t));
572             sch->curr_status.scsw.count = ccw.count - sizeof(indicators);
573             ret = 0;
574         }
575         break;
576     case CCW_CMD_READ_VQ_CONF:
577         if (check_len) {
578             if (ccw.count != sizeof(vq_config)) {
579                 ret = -EINVAL;
580                 break;
581             }
582         } else if (ccw.count < sizeof(vq_config)) {
583             /* Can't execute command. */
584             ret = -EINVAL;
585             break;
586         }
587         if (!ccw.cda) {
588             ret = -EFAULT;
589         } else {
590             ccw_dstream_read(&sch->cds, vq_config.index);
591             vq_config.index = be16_to_cpu(vq_config.index);
592             if (vq_config.index >= VIRTIO_QUEUE_MAX) {
593                 ret = -EINVAL;
594                 break;
595             }
596             vq_config.num_max = virtio_queue_get_num(vdev,
597                                                      vq_config.index);
598             vq_config.num_max = cpu_to_be16(vq_config.num_max);
599             ccw_dstream_write(&sch->cds, vq_config.num_max);
600             sch->curr_status.scsw.count = ccw.count - sizeof(vq_config);
601             ret = 0;
602         }
603         break;
604     case CCW_CMD_SET_IND_ADAPTER:
605         if (check_len) {
606             if (ccw.count != sizeof(thinint)) {
607                 ret = -EINVAL;
608                 break;
609             }
610         } else if (ccw.count < sizeof(thinint)) {
611             /* Can't execute command. */
612             ret = -EINVAL;
613             break;
614         }
615         if (!ccw.cda) {
616             ret = -EFAULT;
617         } else if (dev->indicators && !sch->thinint_active) {
618             /* Trigger a command reject. */
619             ret = -ENOSYS;
620         } else {
621             if (ccw_dstream_read(&sch->cds, thinint)) {
622                 ret = -EFAULT;
623             } else {
624                 thinint.ind_bit = be64_to_cpu(thinint.ind_bit);
625                 thinint.summary_indicator =
626                     be64_to_cpu(thinint.summary_indicator);
627                 thinint.device_indicator =
628                     be64_to_cpu(thinint.device_indicator);
629 
630                 dev->summary_indicator =
631                     get_indicator(thinint.summary_indicator, sizeof(uint8_t));
632                 dev->indicators =
633                     get_indicator(thinint.device_indicator,
634                                   thinint.ind_bit / 8 + 1);
635                 dev->thinint_isc = thinint.isc;
636                 dev->routes.adapter.ind_offset = thinint.ind_bit;
637                 dev->routes.adapter.summary_offset = 7;
638                 dev->routes.adapter.adapter_id = css_get_adapter_id(
639                                                  CSS_IO_ADAPTER_VIRTIO,
640                                                  dev->thinint_isc);
641                 sch->thinint_active = ((dev->indicators != NULL) &&
642                                        (dev->summary_indicator != NULL));
643                 sch->curr_status.scsw.count = ccw.count - sizeof(thinint);
644                 ret = 0;
645             }
646         }
647         break;
648     case CCW_CMD_SET_VIRTIO_REV:
649         len = sizeof(revinfo);
650         if (ccw.count < len) {
651             ret = -EINVAL;
652             break;
653         }
654         if (!ccw.cda) {
655             ret = -EFAULT;
656             break;
657         }
658         ccw_dstream_read_buf(&sch->cds, &revinfo, 4);
659         revinfo.revision = be16_to_cpu(revinfo.revision);
660         revinfo.length = be16_to_cpu(revinfo.length);
661         if (ccw.count < len + revinfo.length ||
662             (check_len && ccw.count > len + revinfo.length)) {
663             ret = -EINVAL;
664             break;
665         }
666         /*
667          * Once we start to support revisions with additional data, we'll
668          * need to fetch it here. Nothing to do for now, though.
669          */
670         if (dev->revision >= 0 ||
671             revinfo.revision > virtio_ccw_rev_max(dev) ||
672             (dev->force_revision_1 && !revinfo.revision)) {
673             ret = -ENOSYS;
674             break;
675         }
676         ret = 0;
677         dev->revision = revinfo.revision;
678         break;
679     default:
680         ret = -ENOSYS;
681         break;
682     }
683     return ret;
684 }
685 
686 static void virtio_sch_disable_cb(SubchDev *sch)
687 {
688     VirtioCcwDevice *dev = sch->driver_data;
689 
690     dev->revision = -1;
691 }
692 
693 static void virtio_ccw_device_realize(VirtioCcwDevice *dev, Error **errp)
694 {
695     VirtIOCCWDeviceClass *k = VIRTIO_CCW_DEVICE_GET_CLASS(dev);
696     CcwDevice *ccw_dev = CCW_DEVICE(dev);
697     CCWDeviceClass *ck = CCW_DEVICE_GET_CLASS(ccw_dev);
698     SubchDev *sch;
699     Error *err = NULL;
700     int i;
701 
702     sch = css_create_sch(ccw_dev->devno, errp);
703     if (!sch) {
704         return;
705     }
706     if (!virtio_ccw_rev_max(dev) && dev->force_revision_1) {
707         error_setg(&err, "Invalid value of property max_rev "
708                    "(is %d expected >= 1)", virtio_ccw_rev_max(dev));
709         goto out_err;
710     }
711 
712     sch->driver_data = dev;
713     sch->ccw_cb = virtio_ccw_cb;
714     sch->disable_cb = virtio_sch_disable_cb;
715     sch->id.reserved = 0xff;
716     sch->id.cu_type = VIRTIO_CCW_CU_TYPE;
717     sch->do_subchannel_work = do_subchannel_work_virtual;
718     ccw_dev->sch = sch;
719     dev->indicators = NULL;
720     dev->revision = -1;
721     for (i = 0; i < ADAPTER_ROUTES_MAX_GSI; i++) {
722         dev->routes.gsi[i] = -1;
723     }
724     css_sch_build_virtual_schib(sch, 0, VIRTIO_CCW_CHPID_TYPE);
725 
726     trace_virtio_ccw_new_device(
727         sch->cssid, sch->ssid, sch->schid, sch->devno,
728         ccw_dev->devno.valid ? "user-configured" : "auto-configured");
729 
730     if (kvm_enabled() && !kvm_eventfds_enabled()) {
731         dev->flags &= ~VIRTIO_CCW_FLAG_USE_IOEVENTFD;
732     }
733 
734     if (k->realize) {
735         k->realize(dev, &err);
736         if (err) {
737             goto out_err;
738         }
739     }
740 
741     ck->realize(ccw_dev, &err);
742     if (err) {
743         goto out_err;
744     }
745 
746     return;
747 
748 out_err:
749     error_propagate(errp, err);
750     css_subch_assign(sch->cssid, sch->ssid, sch->schid, sch->devno, NULL);
751     ccw_dev->sch = NULL;
752     g_free(sch);
753 }
754 
755 static void virtio_ccw_device_unrealize(VirtioCcwDevice *dev, Error **errp)
756 {
757     VirtIOCCWDeviceClass *dc = VIRTIO_CCW_DEVICE_GET_CLASS(dev);
758     CcwDevice *ccw_dev = CCW_DEVICE(dev);
759     SubchDev *sch = ccw_dev->sch;
760 
761     if (dc->unrealize) {
762         dc->unrealize(dev, errp);
763     }
764 
765     if (sch) {
766         css_subch_assign(sch->cssid, sch->ssid, sch->schid, sch->devno, NULL);
767         g_free(sch);
768         ccw_dev->sch = NULL;
769     }
770     if (dev->indicators) {
771         release_indicator(&dev->routes.adapter, dev->indicators);
772         dev->indicators = NULL;
773     }
774 }
775 
776 /* DeviceState to VirtioCcwDevice. Note: used on datapath,
777  * be careful and test performance if you change this.
778  */
779 static inline VirtioCcwDevice *to_virtio_ccw_dev_fast(DeviceState *d)
780 {
781     CcwDevice *ccw_dev = to_ccw_dev_fast(d);
782 
783     return container_of(ccw_dev, VirtioCcwDevice, parent_obj);
784 }
785 
786 static uint8_t virtio_set_ind_atomic(SubchDev *sch, uint64_t ind_loc,
787                                      uint8_t to_be_set)
788 {
789     uint8_t ind_old, ind_new;
790     hwaddr len = 1;
791     uint8_t *ind_addr;
792 
793     ind_addr = cpu_physical_memory_map(ind_loc, &len, true);
794     if (!ind_addr) {
795         error_report("%s(%x.%x.%04x): unable to access indicator",
796                      __func__, sch->cssid, sch->ssid, sch->schid);
797         return -1;
798     }
799     do {
800         ind_old = *ind_addr;
801         ind_new = ind_old | to_be_set;
802     } while (atomic_cmpxchg(ind_addr, ind_old, ind_new) != ind_old);
803     trace_virtio_ccw_set_ind(ind_loc, ind_old, ind_new);
804     cpu_physical_memory_unmap(ind_addr, len, 1, len);
805 
806     return ind_old;
807 }
808 
809 static void virtio_ccw_notify(DeviceState *d, uint16_t vector)
810 {
811     VirtioCcwDevice *dev = to_virtio_ccw_dev_fast(d);
812     CcwDevice *ccw_dev = to_ccw_dev_fast(d);
813     SubchDev *sch = ccw_dev->sch;
814     uint64_t indicators;
815 
816     if (vector == VIRTIO_NO_VECTOR) {
817         return;
818     }
819     /*
820      * vector < VIRTIO_QUEUE_MAX: notification for a virtqueue
821      * vector == VIRTIO_QUEUE_MAX: configuration change notification
822      * bits beyond that are unused and should never be notified for
823      */
824     assert(vector <= VIRTIO_QUEUE_MAX);
825 
826     if (vector < VIRTIO_QUEUE_MAX) {
827         if (!dev->indicators) {
828             return;
829         }
830         if (sch->thinint_active) {
831             /*
832              * In the adapter interrupt case, indicators points to a
833              * memory area that may be (way) larger than 64 bit and
834              * ind_bit indicates the start of the indicators in a big
835              * endian notation.
836              */
837             uint64_t ind_bit = dev->routes.adapter.ind_offset;
838 
839             virtio_set_ind_atomic(sch, dev->indicators->addr +
840                                   (ind_bit + vector) / 8,
841                                   0x80 >> ((ind_bit + vector) % 8));
842             if (!virtio_set_ind_atomic(sch, dev->summary_indicator->addr,
843                                        0x01)) {
844                 css_adapter_interrupt(CSS_IO_ADAPTER_VIRTIO, dev->thinint_isc);
845             }
846         } else {
847             assert(vector < NR_CLASSIC_INDICATOR_BITS);
848             indicators = address_space_ldq(&address_space_memory,
849                                            dev->indicators->addr,
850                                            MEMTXATTRS_UNSPECIFIED,
851                                            NULL);
852             indicators |= 1ULL << vector;
853             address_space_stq(&address_space_memory, dev->indicators->addr,
854                               indicators, MEMTXATTRS_UNSPECIFIED, NULL);
855             css_conditional_io_interrupt(sch);
856         }
857     } else {
858         if (!dev->indicators2) {
859             return;
860         }
861         indicators = address_space_ldq(&address_space_memory,
862                                        dev->indicators2->addr,
863                                        MEMTXATTRS_UNSPECIFIED,
864                                        NULL);
865         indicators |= 1ULL;
866         address_space_stq(&address_space_memory, dev->indicators2->addr,
867                           indicators, MEMTXATTRS_UNSPECIFIED, NULL);
868         css_conditional_io_interrupt(sch);
869     }
870 }
871 
872 static void virtio_ccw_reset(DeviceState *d)
873 {
874     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
875     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
876     VirtIOCCWDeviceClass *vdc = VIRTIO_CCW_DEVICE_GET_CLASS(dev);
877 
878     virtio_ccw_reset_virtio(dev, vdev);
879     if (vdc->parent_reset) {
880         vdc->parent_reset(d);
881     }
882 }
883 
884 static void virtio_ccw_vmstate_change(DeviceState *d, bool running)
885 {
886     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
887 
888     if (running) {
889         virtio_ccw_start_ioeventfd(dev);
890     } else {
891         virtio_ccw_stop_ioeventfd(dev);
892     }
893 }
894 
895 static bool virtio_ccw_query_guest_notifiers(DeviceState *d)
896 {
897     CcwDevice *dev = CCW_DEVICE(d);
898 
899     return !!(dev->sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ENA);
900 }
901 
902 static int virtio_ccw_get_mappings(VirtioCcwDevice *dev)
903 {
904     int r;
905     CcwDevice *ccw_dev = CCW_DEVICE(dev);
906 
907     if (!ccw_dev->sch->thinint_active) {
908         return -EINVAL;
909     }
910 
911     r = map_indicator(&dev->routes.adapter, dev->summary_indicator);
912     if (r) {
913         return r;
914     }
915     r = map_indicator(&dev->routes.adapter, dev->indicators);
916     if (r) {
917         return r;
918     }
919     dev->routes.adapter.summary_addr = dev->summary_indicator->map;
920     dev->routes.adapter.ind_addr = dev->indicators->map;
921 
922     return 0;
923 }
924 
925 static int virtio_ccw_setup_irqroutes(VirtioCcwDevice *dev, int nvqs)
926 {
927     int i;
928     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
929     int ret;
930     S390FLICState *fs = s390_get_flic();
931     S390FLICStateClass *fsc = s390_get_flic_class(fs);
932 
933     ret = virtio_ccw_get_mappings(dev);
934     if (ret) {
935         return ret;
936     }
937     for (i = 0; i < nvqs; i++) {
938         if (!virtio_queue_get_num(vdev, i)) {
939             break;
940         }
941     }
942     dev->routes.num_routes = i;
943     return fsc->add_adapter_routes(fs, &dev->routes);
944 }
945 
946 static void virtio_ccw_release_irqroutes(VirtioCcwDevice *dev, int nvqs)
947 {
948     S390FLICState *fs = s390_get_flic();
949     S390FLICStateClass *fsc = s390_get_flic_class(fs);
950 
951     fsc->release_adapter_routes(fs, &dev->routes);
952 }
953 
954 static int virtio_ccw_add_irqfd(VirtioCcwDevice *dev, int n)
955 {
956     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
957     VirtQueue *vq = virtio_get_queue(vdev, n);
958     EventNotifier *notifier = virtio_queue_get_guest_notifier(vq);
959 
960     return kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, notifier, NULL,
961                                               dev->routes.gsi[n]);
962 }
963 
964 static void virtio_ccw_remove_irqfd(VirtioCcwDevice *dev, int n)
965 {
966     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
967     VirtQueue *vq = virtio_get_queue(vdev, n);
968     EventNotifier *notifier = virtio_queue_get_guest_notifier(vq);
969     int ret;
970 
971     ret = kvm_irqchip_remove_irqfd_notifier_gsi(kvm_state, notifier,
972                                                 dev->routes.gsi[n]);
973     assert(ret == 0);
974 }
975 
976 static int virtio_ccw_set_guest_notifier(VirtioCcwDevice *dev, int n,
977                                          bool assign, bool with_irqfd)
978 {
979     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
980     VirtQueue *vq = virtio_get_queue(vdev, n);
981     EventNotifier *notifier = virtio_queue_get_guest_notifier(vq);
982     VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev);
983 
984     if (assign) {
985         int r = event_notifier_init(notifier, 0);
986 
987         if (r < 0) {
988             return r;
989         }
990         virtio_queue_set_guest_notifier_fd_handler(vq, true, with_irqfd);
991         if (with_irqfd) {
992             r = virtio_ccw_add_irqfd(dev, n);
993             if (r) {
994                 virtio_queue_set_guest_notifier_fd_handler(vq, false,
995                                                            with_irqfd);
996                 return r;
997             }
998         }
999         /*
1000          * We do not support individual masking for channel devices, so we
1001          * need to manually trigger any guest masking callbacks here.
1002          */
1003         if (k->guest_notifier_mask && vdev->use_guest_notifier_mask) {
1004             k->guest_notifier_mask(vdev, n, false);
1005         }
1006         /* get lost events and re-inject */
1007         if (k->guest_notifier_pending &&
1008             k->guest_notifier_pending(vdev, n)) {
1009             event_notifier_set(notifier);
1010         }
1011     } else {
1012         if (k->guest_notifier_mask && vdev->use_guest_notifier_mask) {
1013             k->guest_notifier_mask(vdev, n, true);
1014         }
1015         if (with_irqfd) {
1016             virtio_ccw_remove_irqfd(dev, n);
1017         }
1018         virtio_queue_set_guest_notifier_fd_handler(vq, false, with_irqfd);
1019         event_notifier_cleanup(notifier);
1020     }
1021     return 0;
1022 }
1023 
1024 static int virtio_ccw_set_guest_notifiers(DeviceState *d, int nvqs,
1025                                           bool assigned)
1026 {
1027     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
1028     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
1029     CcwDevice *ccw_dev = CCW_DEVICE(d);
1030     bool with_irqfd = ccw_dev->sch->thinint_active && kvm_irqfds_enabled();
1031     int r, n;
1032 
1033     if (with_irqfd && assigned) {
1034         /* irq routes need to be set up before assigning irqfds */
1035         r = virtio_ccw_setup_irqroutes(dev, nvqs);
1036         if (r < 0) {
1037             goto irqroute_error;
1038         }
1039     }
1040     for (n = 0; n < nvqs; n++) {
1041         if (!virtio_queue_get_num(vdev, n)) {
1042             break;
1043         }
1044         r = virtio_ccw_set_guest_notifier(dev, n, assigned, with_irqfd);
1045         if (r < 0) {
1046             goto assign_error;
1047         }
1048     }
1049     if (with_irqfd && !assigned) {
1050         /* release irq routes after irqfds have been released */
1051         virtio_ccw_release_irqroutes(dev, nvqs);
1052     }
1053     return 0;
1054 
1055 assign_error:
1056     while (--n >= 0) {
1057         virtio_ccw_set_guest_notifier(dev, n, !assigned, false);
1058     }
1059 irqroute_error:
1060     if (with_irqfd && assigned) {
1061         virtio_ccw_release_irqroutes(dev, nvqs);
1062     }
1063     return r;
1064 }
1065 
1066 static void virtio_ccw_save_queue(DeviceState *d, int n, QEMUFile *f)
1067 {
1068     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
1069     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
1070 
1071     qemu_put_be16(f, virtio_queue_vector(vdev, n));
1072 }
1073 
1074 static int virtio_ccw_load_queue(DeviceState *d, int n, QEMUFile *f)
1075 {
1076     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
1077     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
1078     uint16_t vector;
1079 
1080     qemu_get_be16s(f, &vector);
1081     virtio_queue_set_vector(vdev, n , vector);
1082 
1083     return 0;
1084 }
1085 
1086 static void virtio_ccw_save_config(DeviceState *d, QEMUFile *f)
1087 {
1088     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
1089     vmstate_save_state(f, &vmstate_virtio_ccw_dev, dev, NULL);
1090 }
1091 
1092 static int virtio_ccw_load_config(DeviceState *d, QEMUFile *f)
1093 {
1094     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
1095     return vmstate_load_state(f, &vmstate_virtio_ccw_dev, dev, 1);
1096 }
1097 
1098 static void virtio_ccw_pre_plugged(DeviceState *d, Error **errp)
1099 {
1100    VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
1101    VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
1102 
1103     if (dev->max_rev >= 1) {
1104         virtio_add_feature(&vdev->host_features, VIRTIO_F_VERSION_1);
1105     }
1106 }
1107 
1108 /* This is called by virtio-bus just after the device is plugged. */
1109 static void virtio_ccw_device_plugged(DeviceState *d, Error **errp)
1110 {
1111     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
1112     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
1113     CcwDevice *ccw_dev = CCW_DEVICE(d);
1114     SubchDev *sch = ccw_dev->sch;
1115     int n = virtio_get_num_queues(vdev);
1116     S390FLICState *flic = s390_get_flic();
1117 
1118     if (!virtio_has_feature(vdev->host_features, VIRTIO_F_VERSION_1)) {
1119         dev->max_rev = 0;
1120     }
1121 
1122     if (virtio_get_num_queues(vdev) > VIRTIO_QUEUE_MAX) {
1123         error_setg(errp, "The number of virtqueues %d "
1124                    "exceeds virtio limit %d", n,
1125                    VIRTIO_QUEUE_MAX);
1126         return;
1127     }
1128     if (virtio_get_num_queues(vdev) > flic->adapter_routes_max_batch) {
1129         error_setg(errp, "The number of virtqueues %d "
1130                    "exceeds flic adapter route limit %d", n,
1131                    flic->adapter_routes_max_batch);
1132         return;
1133     }
1134 
1135     sch->id.cu_model = virtio_bus_get_vdev_id(&dev->bus);
1136 
1137 
1138     css_generate_sch_crws(sch->cssid, sch->ssid, sch->schid,
1139                           d->hotplugged, 1);
1140 }
1141 
1142 static void virtio_ccw_device_unplugged(DeviceState *d)
1143 {
1144     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
1145 
1146     virtio_ccw_stop_ioeventfd(dev);
1147 }
1148 /**************** Virtio-ccw Bus Device Descriptions *******************/
1149 
1150 static void virtio_ccw_busdev_realize(DeviceState *dev, Error **errp)
1151 {
1152     VirtioCcwDevice *_dev = (VirtioCcwDevice *)dev;
1153 
1154     virtio_ccw_bus_new(&_dev->bus, sizeof(_dev->bus), _dev);
1155     virtio_ccw_device_realize(_dev, errp);
1156 }
1157 
1158 static void virtio_ccw_busdev_unrealize(DeviceState *dev, Error **errp)
1159 {
1160     VirtioCcwDevice *_dev = (VirtioCcwDevice *)dev;
1161 
1162     virtio_ccw_device_unrealize(_dev, errp);
1163 }
1164 
1165 static void virtio_ccw_busdev_unplug(HotplugHandler *hotplug_dev,
1166                                      DeviceState *dev, Error **errp)
1167 {
1168     VirtioCcwDevice *_dev = to_virtio_ccw_dev_fast(dev);
1169 
1170     virtio_ccw_stop_ioeventfd(_dev);
1171 }
1172 
1173 static void virtio_ccw_device_class_init(ObjectClass *klass, void *data)
1174 {
1175     DeviceClass *dc = DEVICE_CLASS(klass);
1176     CCWDeviceClass *k = CCW_DEVICE_CLASS(dc);
1177     VirtIOCCWDeviceClass *vdc = VIRTIO_CCW_DEVICE_CLASS(klass);
1178 
1179     k->unplug = virtio_ccw_busdev_unplug;
1180     dc->realize = virtio_ccw_busdev_realize;
1181     dc->unrealize = virtio_ccw_busdev_unrealize;
1182     dc->bus_type = TYPE_VIRTUAL_CSS_BUS;
1183     device_class_set_parent_reset(dc, virtio_ccw_reset, &vdc->parent_reset);
1184 }
1185 
1186 static const TypeInfo virtio_ccw_device_info = {
1187     .name = TYPE_VIRTIO_CCW_DEVICE,
1188     .parent = TYPE_CCW_DEVICE,
1189     .instance_size = sizeof(VirtioCcwDevice),
1190     .class_init = virtio_ccw_device_class_init,
1191     .class_size = sizeof(VirtIOCCWDeviceClass),
1192     .abstract = true,
1193 };
1194 
1195 /* virtio-ccw-bus */
1196 
1197 static void virtio_ccw_bus_new(VirtioBusState *bus, size_t bus_size,
1198                                VirtioCcwDevice *dev)
1199 {
1200     DeviceState *qdev = DEVICE(dev);
1201     char virtio_bus_name[] = "virtio-bus";
1202 
1203     qbus_create_inplace(bus, bus_size, TYPE_VIRTIO_CCW_BUS,
1204                         qdev, virtio_bus_name);
1205 }
1206 
1207 static void virtio_ccw_bus_class_init(ObjectClass *klass, void *data)
1208 {
1209     VirtioBusClass *k = VIRTIO_BUS_CLASS(klass);
1210     BusClass *bus_class = BUS_CLASS(klass);
1211 
1212     bus_class->max_dev = 1;
1213     k->notify = virtio_ccw_notify;
1214     k->vmstate_change = virtio_ccw_vmstate_change;
1215     k->query_guest_notifiers = virtio_ccw_query_guest_notifiers;
1216     k->set_guest_notifiers = virtio_ccw_set_guest_notifiers;
1217     k->save_queue = virtio_ccw_save_queue;
1218     k->load_queue = virtio_ccw_load_queue;
1219     k->save_config = virtio_ccw_save_config;
1220     k->load_config = virtio_ccw_load_config;
1221     k->pre_plugged = virtio_ccw_pre_plugged;
1222     k->device_plugged = virtio_ccw_device_plugged;
1223     k->device_unplugged = virtio_ccw_device_unplugged;
1224     k->ioeventfd_enabled = virtio_ccw_ioeventfd_enabled;
1225     k->ioeventfd_assign = virtio_ccw_ioeventfd_assign;
1226 }
1227 
1228 static const TypeInfo virtio_ccw_bus_info = {
1229     .name = TYPE_VIRTIO_CCW_BUS,
1230     .parent = TYPE_VIRTIO_BUS,
1231     .instance_size = sizeof(VirtioCcwBusState),
1232     .class_init = virtio_ccw_bus_class_init,
1233 };
1234 
1235 static void virtio_ccw_register(void)
1236 {
1237     type_register_static(&virtio_ccw_bus_info);
1238     type_register_static(&virtio_ccw_device_info);
1239 }
1240 
1241 type_init(virtio_ccw_register)
1242