capstone: Update to upstream "next" branch
[qemu.git] / hw / block / xen-block.c
1 /*
2 * Copyright (c) 2018 Citrix Systems Inc.
3 *
4 * This work is licensed under the terms of the GNU GPL, version 2 or later.
5 * See the COPYING file in the top-level directory.
6 */
7
8 #include "qemu/osdep.h"
9 #include "qemu/cutils.h"
10 #include "qemu/main-loop.h"
11 #include "qemu/module.h"
12 #include "qemu/option.h"
13 #include "qapi/error.h"
14 #include "qapi/qapi-commands-block-core.h"
15 #include "qapi/qapi-commands-qom.h"
16 #include "qapi/qapi-visit-block-core.h"
17 #include "qapi/qobject-input-visitor.h"
18 #include "qapi/visitor.h"
19 #include "qapi/qmp/qdict.h"
20 #include "qapi/qmp/qstring.h"
21 #include "qom/object_interfaces.h"
22 #include "hw/xen/xen_common.h"
23 #include "hw/block/xen_blkif.h"
24 #include "hw/qdev-properties.h"
25 #include "hw/xen/xen-block.h"
26 #include "hw/xen/xen-backend.h"
27 #include "sysemu/blockdev.h"
28 #include "sysemu/block-backend.h"
29 #include "sysemu/iothread.h"
30 #include "dataplane/xen-block.h"
31 #include "trace.h"
32
33 static char *xen_block_get_name(XenDevice *xendev, Error **errp)
34 {
35 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev);
36 XenBlockVdev *vdev = &blockdev->props.vdev;
37
38 return g_strdup_printf("%lu", vdev->number);
39 }
40
41 static void xen_block_disconnect(XenDevice *xendev, Error **errp)
42 {
43 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev);
44 const char *type = object_get_typename(OBJECT(blockdev));
45 XenBlockVdev *vdev = &blockdev->props.vdev;
46
47 trace_xen_block_disconnect(type, vdev->disk, vdev->partition);
48
49 xen_block_dataplane_stop(blockdev->dataplane);
50 }
51
52 static void xen_block_connect(XenDevice *xendev, Error **errp)
53 {
54 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev);
55 const char *type = object_get_typename(OBJECT(blockdev));
56 XenBlockVdev *vdev = &blockdev->props.vdev;
57 BlockConf *conf = &blockdev->props.conf;
58 unsigned int feature_large_sector_size;
59 unsigned int order, nr_ring_ref, *ring_ref, event_channel, protocol;
60 char *str;
61
62 trace_xen_block_connect(type, vdev->disk, vdev->partition);
63
64 if (xen_device_frontend_scanf(xendev, "feature-large-sector-size", "%u",
65 &feature_large_sector_size) != 1) {
66 feature_large_sector_size = 0;
67 }
68
69 if (feature_large_sector_size != 1 &&
70 conf->logical_block_size != XEN_BLKIF_SECTOR_SIZE) {
71 error_setg(errp, "logical_block_size != %u not supported by frontend",
72 XEN_BLKIF_SECTOR_SIZE);
73 return;
74 }
75
76 if (xen_device_frontend_scanf(xendev, "ring-page-order", "%u",
77 &order) != 1) {
78 nr_ring_ref = 1;
79 ring_ref = g_new(unsigned int, nr_ring_ref);
80
81 if (xen_device_frontend_scanf(xendev, "ring-ref", "%u",
82 &ring_ref[0]) != 1) {
83 error_setg(errp, "failed to read ring-ref");
84 g_free(ring_ref);
85 return;
86 }
87 } else if (order <= blockdev->props.max_ring_page_order) {
88 unsigned int i;
89
90 nr_ring_ref = 1 << order;
91 ring_ref = g_new(unsigned int, nr_ring_ref);
92
93 for (i = 0; i < nr_ring_ref; i++) {
94 const char *key = g_strdup_printf("ring-ref%u", i);
95
96 if (xen_device_frontend_scanf(xendev, key, "%u",
97 &ring_ref[i]) != 1) {
98 error_setg(errp, "failed to read %s", key);
99 g_free((gpointer)key);
100 g_free(ring_ref);
101 return;
102 }
103
104 g_free((gpointer)key);
105 }
106 } else {
107 error_setg(errp, "invalid ring-page-order (%d)", order);
108 return;
109 }
110
111 if (xen_device_frontend_scanf(xendev, "event-channel", "%u",
112 &event_channel) != 1) {
113 error_setg(errp, "failed to read event-channel");
114 g_free(ring_ref);
115 return;
116 }
117
118 if (xen_device_frontend_scanf(xendev, "protocol", "%ms",
119 &str) != 1) {
120 protocol = BLKIF_PROTOCOL_NATIVE;
121 } else {
122 if (strcmp(str, XEN_IO_PROTO_ABI_X86_32) == 0) {
123 protocol = BLKIF_PROTOCOL_X86_32;
124 } else if (strcmp(str, XEN_IO_PROTO_ABI_X86_64) == 0) {
125 protocol = BLKIF_PROTOCOL_X86_64;
126 } else {
127 protocol = BLKIF_PROTOCOL_NATIVE;
128 }
129
130 free(str);
131 }
132
133 xen_block_dataplane_start(blockdev->dataplane, ring_ref, nr_ring_ref,
134 event_channel, protocol, errp);
135
136 g_free(ring_ref);
137 }
138
139 static void xen_block_unrealize(XenDevice *xendev)
140 {
141 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev);
142 XenBlockDeviceClass *blockdev_class =
143 XEN_BLOCK_DEVICE_GET_CLASS(xendev);
144 const char *type = object_get_typename(OBJECT(blockdev));
145 XenBlockVdev *vdev = &blockdev->props.vdev;
146
147 if (vdev->type == XEN_BLOCK_VDEV_TYPE_INVALID) {
148 return;
149 }
150
151 trace_xen_block_unrealize(type, vdev->disk, vdev->partition);
152
153 /* Disconnect from the frontend in case this has not already happened */
154 xen_block_disconnect(xendev, NULL);
155
156 xen_block_dataplane_destroy(blockdev->dataplane);
157 blockdev->dataplane = NULL;
158
159 if (blockdev_class->unrealize) {
160 blockdev_class->unrealize(blockdev);
161 }
162 }
163
164 static void xen_block_set_size(XenBlockDevice *blockdev)
165 {
166 const char *type = object_get_typename(OBJECT(blockdev));
167 XenBlockVdev *vdev = &blockdev->props.vdev;
168 BlockConf *conf = &blockdev->props.conf;
169 int64_t sectors = blk_getlength(conf->blk) / conf->logical_block_size;
170 XenDevice *xendev = XEN_DEVICE(blockdev);
171
172 trace_xen_block_size(type, vdev->disk, vdev->partition, sectors);
173
174 xen_device_backend_printf(xendev, "sectors", "%"PRIi64, sectors);
175 }
176
177 static void xen_block_resize_cb(void *opaque)
178 {
179 XenBlockDevice *blockdev = opaque;
180 XenDevice *xendev = XEN_DEVICE(blockdev);
181 enum xenbus_state state = xen_device_backend_get_state(xendev);
182
183 xen_block_set_size(blockdev);
184
185 /*
186 * Mimic the behaviour of Linux xen-blkback and re-write the state
187 * to trigger the frontend watch.
188 */
189 xen_device_backend_printf(xendev, "state", "%u", state);
190 }
191
192 static const BlockDevOps xen_block_dev_ops = {
193 .resize_cb = xen_block_resize_cb,
194 };
195
196 static void xen_block_realize(XenDevice *xendev, Error **errp)
197 {
198 ERRP_GUARD();
199 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev);
200 XenBlockDeviceClass *blockdev_class =
201 XEN_BLOCK_DEVICE_GET_CLASS(xendev);
202 const char *type = object_get_typename(OBJECT(blockdev));
203 XenBlockVdev *vdev = &blockdev->props.vdev;
204 BlockConf *conf = &blockdev->props.conf;
205 BlockBackend *blk = conf->blk;
206
207 if (vdev->type == XEN_BLOCK_VDEV_TYPE_INVALID) {
208 error_setg(errp, "vdev property not set");
209 return;
210 }
211
212 trace_xen_block_realize(type, vdev->disk, vdev->partition);
213
214 if (blockdev_class->realize) {
215 blockdev_class->realize(blockdev, errp);
216 if (*errp) {
217 return;
218 }
219 }
220
221 /*
222 * The blkif protocol does not deal with removable media, so it must
223 * always be present, even for CDRom devices.
224 */
225 assert(blk);
226 if (!blk_is_inserted(blk)) {
227 error_setg(errp, "device needs media, but drive is empty");
228 return;
229 }
230
231 if (!blkconf_apply_backend_options(conf, blockdev->info & VDISK_READONLY,
232 true, errp)) {
233 return;
234 }
235
236 if (!(blockdev->info & VDISK_CDROM) &&
237 !blkconf_geometry(conf, NULL, 65535, 255, 255, errp)) {
238 return;
239 }
240
241 if (!blkconf_blocksizes(conf, errp)) {
242 return;
243 }
244
245 blk_set_dev_ops(blk, &xen_block_dev_ops, blockdev);
246 blk_set_guest_block_size(blk, conf->logical_block_size);
247
248 if (conf->discard_granularity == -1) {
249 conf->discard_granularity = conf->physical_block_size;
250 }
251
252 if (blk_get_flags(blk) & BDRV_O_UNMAP) {
253 xen_device_backend_printf(xendev, "feature-discard", "%u", 1);
254 xen_device_backend_printf(xendev, "discard-granularity", "%u",
255 conf->discard_granularity);
256 }
257
258 xen_device_backend_printf(xendev, "feature-flush-cache", "%u", 1);
259 xen_device_backend_printf(xendev, "max-ring-page-order", "%u",
260 blockdev->props.max_ring_page_order);
261 xen_device_backend_printf(xendev, "info", "%u", blockdev->info);
262
263 xen_device_frontend_printf(xendev, "virtual-device", "%lu",
264 vdev->number);
265 xen_device_frontend_printf(xendev, "device-type", "%s",
266 blockdev->device_type);
267
268 xen_device_backend_printf(xendev, "sector-size", "%u",
269 conf->logical_block_size);
270
271 xen_block_set_size(blockdev);
272
273 blockdev->dataplane =
274 xen_block_dataplane_create(xendev, blk, conf->logical_block_size,
275 blockdev->props.iothread);
276 }
277
278 static void xen_block_frontend_changed(XenDevice *xendev,
279 enum xenbus_state frontend_state,
280 Error **errp)
281 {
282 ERRP_GUARD();
283 enum xenbus_state backend_state = xen_device_backend_get_state(xendev);
284
285 switch (frontend_state) {
286 case XenbusStateInitialised:
287 case XenbusStateConnected:
288 if (backend_state == XenbusStateConnected) {
289 break;
290 }
291
292 xen_block_disconnect(xendev, errp);
293 if (*errp) {
294 break;
295 }
296
297 xen_block_connect(xendev, errp);
298 if (*errp) {
299 break;
300 }
301
302 xen_device_backend_set_state(xendev, XenbusStateConnected);
303 break;
304
305 case XenbusStateClosing:
306 xen_device_backend_set_state(xendev, XenbusStateClosing);
307 break;
308
309 case XenbusStateClosed:
310 case XenbusStateUnknown:
311 xen_block_disconnect(xendev, errp);
312 if (*errp) {
313 break;
314 }
315
316 xen_device_backend_set_state(xendev, XenbusStateClosed);
317 break;
318
319 default:
320 break;
321 }
322 }
323
324 static char *disk_to_vbd_name(unsigned int disk)
325 {
326 char *name, *prefix = (disk >= 26) ?
327 disk_to_vbd_name((disk / 26) - 1) : g_strdup("");
328
329 name = g_strdup_printf("%s%c", prefix, 'a' + disk % 26);
330 g_free(prefix);
331
332 return name;
333 }
334
335 static void xen_block_get_vdev(Object *obj, Visitor *v, const char *name,
336 void *opaque, Error **errp)
337 {
338 DeviceState *dev = DEVICE(obj);
339 Property *prop = opaque;
340 XenBlockVdev *vdev = qdev_get_prop_ptr(dev, prop);
341 char *str;
342
343 switch (vdev->type) {
344 case XEN_BLOCK_VDEV_TYPE_DP:
345 str = g_strdup_printf("d%lup%lu", vdev->disk, vdev->partition);
346 break;
347
348 case XEN_BLOCK_VDEV_TYPE_XVD:
349 case XEN_BLOCK_VDEV_TYPE_HD:
350 case XEN_BLOCK_VDEV_TYPE_SD: {
351 char *name = disk_to_vbd_name(vdev->disk);
352
353 str = g_strdup_printf("%s%s%lu",
354 (vdev->type == XEN_BLOCK_VDEV_TYPE_XVD) ?
355 "xvd" :
356 (vdev->type == XEN_BLOCK_VDEV_TYPE_HD) ?
357 "hd" :
358 "sd",
359 name, vdev->partition);
360 g_free(name);
361 break;
362 }
363 default:
364 error_setg(errp, "invalid vdev type");
365 return;
366 }
367
368 visit_type_str(v, name, &str, errp);
369 g_free(str);
370 }
371
372 static int vbd_name_to_disk(const char *name, const char **endp,
373 unsigned long *disk)
374 {
375 unsigned int n = 0;
376
377 while (*name != '\0') {
378 if (!g_ascii_isalpha(*name) || !g_ascii_islower(*name)) {
379 break;
380 }
381
382 n *= 26;
383 n += *name++ - 'a' + 1;
384 }
385 *endp = name;
386
387 if (!n) {
388 return -1;
389 }
390
391 *disk = n - 1;
392
393 return 0;
394 }
395
396 static void xen_block_set_vdev(Object *obj, Visitor *v, const char *name,
397 void *opaque, Error **errp)
398 {
399 DeviceState *dev = DEVICE(obj);
400 Property *prop = opaque;
401 XenBlockVdev *vdev = qdev_get_prop_ptr(dev, prop);
402 char *str, *p;
403 const char *end;
404
405 if (dev->realized) {
406 qdev_prop_set_after_realize(dev, name, errp);
407 return;
408 }
409
410 if (!visit_type_str(v, name, &str, errp)) {
411 return;
412 }
413
414 p = strchr(str, 'd');
415 if (!p) {
416 goto invalid;
417 }
418
419 *p++ = '\0';
420 if (*str == '\0') {
421 vdev->type = XEN_BLOCK_VDEV_TYPE_DP;
422 } else if (strcmp(str, "xv") == 0) {
423 vdev->type = XEN_BLOCK_VDEV_TYPE_XVD;
424 } else if (strcmp(str, "h") == 0) {
425 vdev->type = XEN_BLOCK_VDEV_TYPE_HD;
426 } else if (strcmp(str, "s") == 0) {
427 vdev->type = XEN_BLOCK_VDEV_TYPE_SD;
428 } else {
429 goto invalid;
430 }
431
432 if (vdev->type == XEN_BLOCK_VDEV_TYPE_DP) {
433 if (qemu_strtoul(p, &end, 10, &vdev->disk)) {
434 goto invalid;
435 }
436
437 if (*end == 'p') {
438 if (*(++end) == '\0') {
439 goto invalid;
440 }
441 }
442 } else {
443 if (vbd_name_to_disk(p, &end, &vdev->disk)) {
444 goto invalid;
445 }
446 }
447
448 if (*end != '\0') {
449 p = (char *)end;
450
451 if (qemu_strtoul(p, &end, 10, &vdev->partition)) {
452 goto invalid;
453 }
454
455 if (*end != '\0') {
456 goto invalid;
457 }
458 } else {
459 vdev->partition = 0;
460 }
461
462 switch (vdev->type) {
463 case XEN_BLOCK_VDEV_TYPE_DP:
464 case XEN_BLOCK_VDEV_TYPE_XVD:
465 if (vdev->disk < (1 << 4) && vdev->partition < (1 << 4)) {
466 vdev->number = (202 << 8) | (vdev->disk << 4) |
467 vdev->partition;
468 } else if (vdev->disk < (1 << 20) && vdev->partition < (1 << 8)) {
469 vdev->number = (1 << 28) | (vdev->disk << 8) |
470 vdev->partition;
471 } else {
472 goto invalid;
473 }
474 break;
475
476 case XEN_BLOCK_VDEV_TYPE_HD:
477 if ((vdev->disk == 0 || vdev->disk == 1) &&
478 vdev->partition < (1 << 6)) {
479 vdev->number = (3 << 8) | (vdev->disk << 6) | vdev->partition;
480 } else if ((vdev->disk == 2 || vdev->disk == 3) &&
481 vdev->partition < (1 << 6)) {
482 vdev->number = (22 << 8) | ((vdev->disk - 2) << 6) |
483 vdev->partition;
484 } else {
485 goto invalid;
486 }
487 break;
488
489 case XEN_BLOCK_VDEV_TYPE_SD:
490 if (vdev->disk < (1 << 4) && vdev->partition < (1 << 4)) {
491 vdev->number = (8 << 8) | (vdev->disk << 4) | vdev->partition;
492 } else {
493 goto invalid;
494 }
495 break;
496
497 default:
498 goto invalid;
499 }
500
501 g_free(str);
502 return;
503
504 invalid:
505 error_setg(errp, "invalid virtual disk specifier");
506
507 vdev->type = XEN_BLOCK_VDEV_TYPE_INVALID;
508 g_free(str);
509 }
510
511 /*
512 * This property deals with 'vdev' names adhering to the Xen VBD naming
513 * scheme described in:
514 *
515 * https://xenbits.xen.org/docs/unstable/man/xen-vbd-interface.7.html
516 */
517 const PropertyInfo xen_block_prop_vdev = {
518 .name = "str",
519 .description = "Virtual Disk specifier: d*p*/xvd*/hd*/sd*",
520 .get = xen_block_get_vdev,
521 .set = xen_block_set_vdev,
522 };
523
524 static Property xen_block_props[] = {
525 DEFINE_PROP("vdev", XenBlockDevice, props.vdev,
526 xen_block_prop_vdev, XenBlockVdev),
527 DEFINE_BLOCK_PROPERTIES(XenBlockDevice, props.conf),
528 DEFINE_PROP_UINT32("max-ring-page-order", XenBlockDevice,
529 props.max_ring_page_order, 4),
530 DEFINE_PROP_LINK("iothread", XenBlockDevice, props.iothread,
531 TYPE_IOTHREAD, IOThread *),
532 DEFINE_PROP_END_OF_LIST()
533 };
534
535 static void xen_block_class_init(ObjectClass *class, void *data)
536 {
537 DeviceClass *dev_class = DEVICE_CLASS(class);
538 XenDeviceClass *xendev_class = XEN_DEVICE_CLASS(class);
539
540 xendev_class->backend = "qdisk";
541 xendev_class->device = "vbd";
542 xendev_class->get_name = xen_block_get_name;
543 xendev_class->realize = xen_block_realize;
544 xendev_class->frontend_changed = xen_block_frontend_changed;
545 xendev_class->unrealize = xen_block_unrealize;
546
547 device_class_set_props(dev_class, xen_block_props);
548 }
549
550 static const TypeInfo xen_block_type_info = {
551 .name = TYPE_XEN_BLOCK_DEVICE,
552 .parent = TYPE_XEN_DEVICE,
553 .instance_size = sizeof(XenBlockDevice),
554 .abstract = true,
555 .class_size = sizeof(XenBlockDeviceClass),
556 .class_init = xen_block_class_init,
557 };
558
559 static void xen_disk_unrealize(XenBlockDevice *blockdev)
560 {
561 trace_xen_disk_unrealize();
562 }
563
564 static void xen_disk_realize(XenBlockDevice *blockdev, Error **errp)
565 {
566 BlockConf *conf = &blockdev->props.conf;
567
568 trace_xen_disk_realize();
569
570 blockdev->device_type = "disk";
571
572 if (!conf->blk) {
573 error_setg(errp, "drive property not set");
574 return;
575 }
576
577 blockdev->info = blk_is_read_only(conf->blk) ? VDISK_READONLY : 0;
578 }
579
580 static void xen_disk_class_init(ObjectClass *class, void *data)
581 {
582 DeviceClass *dev_class = DEVICE_CLASS(class);
583 XenBlockDeviceClass *blockdev_class = XEN_BLOCK_DEVICE_CLASS(class);
584
585 blockdev_class->realize = xen_disk_realize;
586 blockdev_class->unrealize = xen_disk_unrealize;
587
588 dev_class->desc = "Xen Disk Device";
589 }
590
591 static const TypeInfo xen_disk_type_info = {
592 .name = TYPE_XEN_DISK_DEVICE,
593 .parent = TYPE_XEN_BLOCK_DEVICE,
594 .instance_size = sizeof(XenDiskDevice),
595 .class_init = xen_disk_class_init,
596 };
597
598 static void xen_cdrom_unrealize(XenBlockDevice *blockdev)
599 {
600 trace_xen_cdrom_unrealize();
601 }
602
603 static void xen_cdrom_realize(XenBlockDevice *blockdev, Error **errp)
604 {
605 BlockConf *conf = &blockdev->props.conf;
606
607 trace_xen_cdrom_realize();
608
609 blockdev->device_type = "cdrom";
610
611 if (!conf->blk) {
612 int rc;
613
614 /* Set up an empty drive */
615 conf->blk = blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL);
616
617 rc = blk_attach_dev(conf->blk, DEVICE(blockdev));
618 if (!rc) {
619 error_setg_errno(errp, -rc, "failed to create drive");
620 return;
621 }
622 }
623
624 blockdev->info = VDISK_READONLY | VDISK_CDROM;
625 }
626
627 static void xen_cdrom_class_init(ObjectClass *class, void *data)
628 {
629 DeviceClass *dev_class = DEVICE_CLASS(class);
630 XenBlockDeviceClass *blockdev_class = XEN_BLOCK_DEVICE_CLASS(class);
631
632 blockdev_class->realize = xen_cdrom_realize;
633 blockdev_class->unrealize = xen_cdrom_unrealize;
634
635 dev_class->desc = "Xen CD-ROM Device";
636 }
637
638 static const TypeInfo xen_cdrom_type_info = {
639 .name = TYPE_XEN_CDROM_DEVICE,
640 .parent = TYPE_XEN_BLOCK_DEVICE,
641 .instance_size = sizeof(XenCDRomDevice),
642 .class_init = xen_cdrom_class_init,
643 };
644
645 static void xen_block_register_types(void)
646 {
647 type_register_static(&xen_block_type_info);
648 type_register_static(&xen_disk_type_info);
649 type_register_static(&xen_cdrom_type_info);
650 }
651
652 type_init(xen_block_register_types)
653
654 static void xen_block_blockdev_del(const char *node_name, Error **errp)
655 {
656 trace_xen_block_blockdev_del(node_name);
657
658 qmp_blockdev_del(node_name, errp);
659 }
660
661 static char *xen_block_blockdev_add(const char *id, QDict *qdict,
662 Error **errp)
663 {
664 ERRP_GUARD();
665 const char *driver = qdict_get_try_str(qdict, "driver");
666 BlockdevOptions *options = NULL;
667 char *node_name;
668 Visitor *v;
669
670 if (!driver) {
671 error_setg(errp, "no 'driver' parameter");
672 return NULL;
673 }
674
675 node_name = g_strdup_printf("%s-%s", id, driver);
676 qdict_put_str(qdict, "node-name", node_name);
677
678 trace_xen_block_blockdev_add(node_name);
679
680 v = qobject_input_visitor_new(QOBJECT(qdict));
681 visit_type_BlockdevOptions(v, NULL, &options, errp);
682 visit_free(v);
683 if (!options) {
684 goto fail;
685 }
686
687 qmp_blockdev_add(options, errp);
688
689 if (*errp) {
690 goto fail;
691 }
692
693 qapi_free_BlockdevOptions(options);
694
695 return node_name;
696
697 fail:
698 if (options) {
699 qapi_free_BlockdevOptions(options);
700 }
701 g_free(node_name);
702
703 return NULL;
704 }
705
706 static void xen_block_drive_destroy(XenBlockDrive *drive, Error **errp)
707 {
708 ERRP_GUARD();
709 char *node_name = drive->node_name;
710
711 if (node_name) {
712 xen_block_blockdev_del(node_name, errp);
713 if (*errp) {
714 return;
715 }
716 g_free(node_name);
717 drive->node_name = NULL;
718 }
719 g_free(drive->id);
720 g_free(drive);
721 }
722
723 static XenBlockDrive *xen_block_drive_create(const char *id,
724 const char *device_type,
725 QDict *opts, Error **errp)
726 {
727 ERRP_GUARD();
728 const char *params = qdict_get_try_str(opts, "params");
729 const char *mode = qdict_get_try_str(opts, "mode");
730 const char *direct_io_safe = qdict_get_try_str(opts, "direct-io-safe");
731 const char *discard_enable = qdict_get_try_str(opts, "discard-enable");
732 char *driver = NULL;
733 char *filename = NULL;
734 XenBlockDrive *drive = NULL;
735 QDict *file_layer;
736 QDict *driver_layer;
737
738 if (params) {
739 char **v = g_strsplit(params, ":", 2);
740
741 if (v[1] == NULL) {
742 filename = g_strdup(v[0]);
743 driver = g_strdup("raw");
744 } else {
745 if (strcmp(v[0], "aio") == 0) {
746 driver = g_strdup("raw");
747 } else if (strcmp(v[0], "vhd") == 0) {
748 driver = g_strdup("vpc");
749 } else {
750 driver = g_strdup(v[0]);
751 }
752 filename = g_strdup(v[1]);
753 }
754
755 g_strfreev(v);
756 } else {
757 error_setg(errp, "no params");
758 goto done;
759 }
760
761 assert(filename);
762 assert(driver);
763
764 drive = g_new0(XenBlockDrive, 1);
765 drive->id = g_strdup(id);
766
767 file_layer = qdict_new();
768 driver_layer = qdict_new();
769
770 qdict_put_str(file_layer, "driver", "file");
771 qdict_put_str(file_layer, "filename", filename);
772 g_free(filename);
773
774 if (mode && *mode != 'w') {
775 qdict_put_bool(file_layer, "read-only", true);
776 }
777
778 if (direct_io_safe) {
779 unsigned long value;
780
781 if (!qemu_strtoul(direct_io_safe, NULL, 2, &value) && !!value) {
782 QDict *cache_qdict = qdict_new();
783
784 qdict_put_bool(cache_qdict, "direct", true);
785 qdict_put(file_layer, "cache", cache_qdict);
786
787 qdict_put_str(file_layer, "aio", "native");
788 }
789 }
790
791 if (discard_enable) {
792 unsigned long value;
793
794 if (!qemu_strtoul(discard_enable, NULL, 2, &value) && !!value) {
795 qdict_put_str(file_layer, "discard", "unmap");
796 qdict_put_str(driver_layer, "discard", "unmap");
797 }
798 }
799
800 /*
801 * It is necessary to turn file locking off as an emulated device
802 * may have already opened the same image file.
803 */
804 qdict_put_str(file_layer, "locking", "off");
805
806 qdict_put_str(driver_layer, "driver", driver);
807 g_free(driver);
808
809 qdict_put(driver_layer, "file", file_layer);
810
811 g_assert(!drive->node_name);
812 drive->node_name = xen_block_blockdev_add(drive->id, driver_layer,
813 errp);
814
815 qobject_unref(driver_layer);
816
817 done:
818 if (*errp) {
819 xen_block_drive_destroy(drive, NULL);
820 return NULL;
821 }
822
823 return drive;
824 }
825
826 static const char *xen_block_drive_get_node_name(XenBlockDrive *drive)
827 {
828 return drive->node_name ? drive->node_name : "";
829 }
830
831 static void xen_block_iothread_destroy(XenBlockIOThread *iothread,
832 Error **errp)
833 {
834 qmp_object_del(iothread->id, errp);
835
836 g_free(iothread->id);
837 g_free(iothread);
838 }
839
840 static XenBlockIOThread *xen_block_iothread_create(const char *id,
841 Error **errp)
842 {
843 ERRP_GUARD();
844 XenBlockIOThread *iothread = g_new(XenBlockIOThread, 1);
845 QDict *opts;
846 QObject *ret_data = NULL;
847
848 iothread->id = g_strdup(id);
849
850 opts = qdict_new();
851 qdict_put_str(opts, "qom-type", TYPE_IOTHREAD);
852 qdict_put_str(opts, "id", id);
853 qmp_object_add(opts, &ret_data, errp);
854 qobject_unref(opts);
855 qobject_unref(ret_data);
856
857 if (*errp) {
858 g_free(iothread->id);
859 g_free(iothread);
860 return NULL;
861 }
862
863 return iothread;
864 }
865
866 static void xen_block_device_create(XenBackendInstance *backend,
867 QDict *opts, Error **errp)
868 {
869 ERRP_GUARD();
870 XenBus *xenbus = xen_backend_get_bus(backend);
871 const char *name = xen_backend_get_name(backend);
872 unsigned long number;
873 const char *vdev, *device_type;
874 XenBlockDrive *drive = NULL;
875 XenBlockIOThread *iothread = NULL;
876 XenDevice *xendev = NULL;
877 const char *type;
878 XenBlockDevice *blockdev;
879
880 if (qemu_strtoul(name, NULL, 10, &number)) {
881 error_setg(errp, "failed to parse name '%s'", name);
882 goto fail;
883 }
884
885 trace_xen_block_device_create(number);
886
887 vdev = qdict_get_try_str(opts, "dev");
888 if (!vdev) {
889 error_setg(errp, "no dev parameter");
890 goto fail;
891 }
892
893 device_type = qdict_get_try_str(opts, "device-type");
894 if (!device_type) {
895 error_setg(errp, "no device-type parameter");
896 goto fail;
897 }
898
899 if (!strcmp(device_type, "disk")) {
900 type = TYPE_XEN_DISK_DEVICE;
901 } else if (!strcmp(device_type, "cdrom")) {
902 type = TYPE_XEN_CDROM_DEVICE;
903 } else {
904 error_setg(errp, "invalid device-type parameter '%s'", device_type);
905 goto fail;
906 }
907
908 drive = xen_block_drive_create(vdev, device_type, opts, errp);
909 if (!drive) {
910 error_prepend(errp, "failed to create drive: ");
911 goto fail;
912 }
913
914 iothread = xen_block_iothread_create(vdev, errp);
915 if (*errp) {
916 error_prepend(errp, "failed to create iothread: ");
917 goto fail;
918 }
919
920 xendev = XEN_DEVICE(qdev_new(type));
921 blockdev = XEN_BLOCK_DEVICE(xendev);
922
923 if (!object_property_set_str(OBJECT(xendev), "vdev", vdev,
924 errp)) {
925 error_prepend(errp, "failed to set 'vdev': ");
926 goto fail;
927 }
928
929 if (!object_property_set_str(OBJECT(xendev), "drive",
930 xen_block_drive_get_node_name(drive),
931 errp)) {
932 error_prepend(errp, "failed to set 'drive': ");
933 goto fail;
934 }
935
936 if (!object_property_set_str(OBJECT(xendev), "iothread", iothread->id,
937 errp)) {
938 error_prepend(errp, "failed to set 'iothread': ");
939 goto fail;
940 }
941
942 blockdev->iothread = iothread;
943 blockdev->drive = drive;
944
945 if (!qdev_realize_and_unref(DEVICE(xendev), BUS(xenbus), errp)) {
946 error_prepend(errp, "realization of device %s failed: ", type);
947 goto fail;
948 }
949
950 xen_backend_set_device(backend, xendev);
951 return;
952
953 fail:
954 if (xendev) {
955 object_unparent(OBJECT(xendev));
956 }
957
958 if (iothread) {
959 xen_block_iothread_destroy(iothread, NULL);
960 }
961
962 if (drive) {
963 xen_block_drive_destroy(drive, NULL);
964 }
965 }
966
967 static void xen_block_device_destroy(XenBackendInstance *backend,
968 Error **errp)
969 {
970 ERRP_GUARD();
971 XenDevice *xendev = xen_backend_get_device(backend);
972 XenBlockDevice *blockdev = XEN_BLOCK_DEVICE(xendev);
973 XenBlockVdev *vdev = &blockdev->props.vdev;
974 XenBlockDrive *drive = blockdev->drive;
975 XenBlockIOThread *iothread = blockdev->iothread;
976
977 trace_xen_block_device_destroy(vdev->number);
978
979 object_unparent(OBJECT(xendev));
980
981 if (iothread) {
982 xen_block_iothread_destroy(iothread, errp);
983 if (*errp) {
984 error_prepend(errp, "failed to destroy iothread: ");
985 return;
986 }
987 }
988
989 if (drive) {
990 xen_block_drive_destroy(drive, errp);
991 if (*errp) {
992 error_prepend(errp, "failed to destroy drive: ");
993 return;
994 }
995 }
996 }
997
998 static const XenBackendInfo xen_block_backend_info = {
999 .type = "qdisk",
1000 .create = xen_block_device_create,
1001 .destroy = xen_block_device_destroy,
1002 };
1003
1004 static void xen_block_register_backend(void)
1005 {
1006 xen_backend_register(&xen_block_backend_info);
1007 }
1008
1009 xen_backend_init(xen_block_register_backend);