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1 | /* | |
2 | * QEMU Block backends | |
3 | * | |
4 | * Copyright (C) 2014-2016 Red Hat, Inc. | |
5 | * | |
6 | * Authors: | |
7 | * Markus Armbruster <armbru@redhat.com>, | |
8 | * | |
9 | * This work is licensed under the terms of the GNU LGPL, version 2.1 | |
10 | * or later. See the COPYING.LIB file in the top-level directory. | |
11 | */ | |
12 | ||
13 | #include "qemu/osdep.h" | |
14 | #include "sysemu/block-backend.h" | |
15 | #include "block/block_int.h" | |
16 | #include "block/blockjob.h" | |
17 | #include "block/coroutines.h" | |
18 | #include "block/throttle-groups.h" | |
19 | #include "hw/qdev-core.h" | |
20 | #include "sysemu/blockdev.h" | |
21 | #include "sysemu/runstate.h" | |
22 | #include "sysemu/replay.h" | |
23 | #include "qapi/error.h" | |
24 | #include "qapi/qapi-events-block.h" | |
25 | #include "qemu/id.h" | |
26 | #include "qemu/main-loop.h" | |
27 | #include "qemu/option.h" | |
28 | #include "trace.h" | |
29 | #include "migration/misc.h" | |
30 | ||
31 | /* Number of coroutines to reserve per attached device model */ | |
32 | #define COROUTINE_POOL_RESERVATION 64 | |
33 | ||
34 | #define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */ | |
35 | ||
36 | typedef struct BlockBackendAioNotifier { | |
37 | void (*attached_aio_context)(AioContext *new_context, void *opaque); | |
38 | void (*detach_aio_context)(void *opaque); | |
39 | void *opaque; | |
40 | QLIST_ENTRY(BlockBackendAioNotifier) list; | |
41 | } BlockBackendAioNotifier; | |
42 | ||
43 | struct BlockBackend { | |
44 | char *name; | |
45 | int refcnt; | |
46 | BdrvChild *root; | |
47 | AioContext *ctx; | |
48 | DriveInfo *legacy_dinfo; /* null unless created by drive_new() */ | |
49 | QTAILQ_ENTRY(BlockBackend) link; /* for block_backends */ | |
50 | QTAILQ_ENTRY(BlockBackend) monitor_link; /* for monitor_block_backends */ | |
51 | BlockBackendPublic public; | |
52 | ||
53 | DeviceState *dev; /* attached device model, if any */ | |
54 | const BlockDevOps *dev_ops; | |
55 | void *dev_opaque; | |
56 | ||
57 | /* If the BDS tree is removed, some of its options are stored here (which | |
58 | * can be used to restore those options in the new BDS on insert) */ | |
59 | BlockBackendRootState root_state; | |
60 | ||
61 | bool enable_write_cache; | |
62 | ||
63 | /* I/O stats (display with "info blockstats"). */ | |
64 | BlockAcctStats stats; | |
65 | ||
66 | BlockdevOnError on_read_error, on_write_error; | |
67 | bool iostatus_enabled; | |
68 | BlockDeviceIoStatus iostatus; | |
69 | ||
70 | uint64_t perm; | |
71 | uint64_t shared_perm; | |
72 | bool disable_perm; | |
73 | ||
74 | bool allow_aio_context_change; | |
75 | bool allow_write_beyond_eof; | |
76 | ||
77 | /* Protected by BQL */ | |
78 | NotifierList remove_bs_notifiers, insert_bs_notifiers; | |
79 | QLIST_HEAD(, BlockBackendAioNotifier) aio_notifiers; | |
80 | ||
81 | int quiesce_counter; /* atomic: written under BQL, read by other threads */ | |
82 | QemuMutex queued_requests_lock; /* protects queued_requests */ | |
83 | CoQueue queued_requests; | |
84 | bool disable_request_queuing; /* atomic */ | |
85 | ||
86 | VMChangeStateEntry *vmsh; | |
87 | bool force_allow_inactivate; | |
88 | ||
89 | /* Number of in-flight aio requests. BlockDriverState also counts | |
90 | * in-flight requests but aio requests can exist even when blk->root is | |
91 | * NULL, so we cannot rely on its counter for that case. | |
92 | * Accessed with atomic ops. | |
93 | */ | |
94 | unsigned int in_flight; | |
95 | }; | |
96 | ||
97 | typedef struct BlockBackendAIOCB { | |
98 | BlockAIOCB common; | |
99 | BlockBackend *blk; | |
100 | int ret; | |
101 | } BlockBackendAIOCB; | |
102 | ||
103 | static const AIOCBInfo block_backend_aiocb_info = { | |
104 | .aiocb_size = sizeof(BlockBackendAIOCB), | |
105 | }; | |
106 | ||
107 | static void drive_info_del(DriveInfo *dinfo); | |
108 | static BlockBackend *bdrv_first_blk(BlockDriverState *bs); | |
109 | ||
110 | /* All BlockBackends. Protected by BQL. */ | |
111 | static QTAILQ_HEAD(, BlockBackend) block_backends = | |
112 | QTAILQ_HEAD_INITIALIZER(block_backends); | |
113 | ||
114 | /* | |
115 | * All BlockBackends referenced by the monitor and which are iterated through by | |
116 | * blk_next(). Protected by BQL. | |
117 | */ | |
118 | static QTAILQ_HEAD(, BlockBackend) monitor_block_backends = | |
119 | QTAILQ_HEAD_INITIALIZER(monitor_block_backends); | |
120 | ||
121 | static int coroutine_mixed_fn GRAPH_RDLOCK | |
122 | blk_set_perm_locked(BlockBackend *blk, uint64_t perm, uint64_t shared_perm, | |
123 | Error **errp); | |
124 | ||
125 | static void blk_root_inherit_options(BdrvChildRole role, bool parent_is_format, | |
126 | int *child_flags, QDict *child_options, | |
127 | int parent_flags, QDict *parent_options) | |
128 | { | |
129 | /* We're not supposed to call this function for root nodes */ | |
130 | abort(); | |
131 | } | |
132 | static void blk_root_drained_begin(BdrvChild *child); | |
133 | static bool blk_root_drained_poll(BdrvChild *child); | |
134 | static void blk_root_drained_end(BdrvChild *child); | |
135 | ||
136 | static void blk_root_change_media(BdrvChild *child, bool load); | |
137 | static void blk_root_resize(BdrvChild *child); | |
138 | ||
139 | static bool blk_root_change_aio_ctx(BdrvChild *child, AioContext *ctx, | |
140 | GHashTable *visited, Transaction *tran, | |
141 | Error **errp); | |
142 | ||
143 | static char *blk_root_get_parent_desc(BdrvChild *child) | |
144 | { | |
145 | BlockBackend *blk = child->opaque; | |
146 | g_autofree char *dev_id = NULL; | |
147 | ||
148 | if (blk->name) { | |
149 | return g_strdup_printf("block device '%s'", blk->name); | |
150 | } | |
151 | ||
152 | dev_id = blk_get_attached_dev_id(blk); | |
153 | if (*dev_id) { | |
154 | return g_strdup_printf("block device '%s'", dev_id); | |
155 | } else { | |
156 | /* TODO Callback into the BB owner for something more detailed */ | |
157 | return g_strdup("an unnamed block device"); | |
158 | } | |
159 | } | |
160 | ||
161 | static const char *blk_root_get_name(BdrvChild *child) | |
162 | { | |
163 | return blk_name(child->opaque); | |
164 | } | |
165 | ||
166 | static void blk_vm_state_changed(void *opaque, bool running, RunState state) | |
167 | { | |
168 | Error *local_err = NULL; | |
169 | BlockBackend *blk = opaque; | |
170 | ||
171 | if (state == RUN_STATE_INMIGRATE) { | |
172 | return; | |
173 | } | |
174 | ||
175 | qemu_del_vm_change_state_handler(blk->vmsh); | |
176 | blk->vmsh = NULL; | |
177 | blk_set_perm(blk, blk->perm, blk->shared_perm, &local_err); | |
178 | if (local_err) { | |
179 | error_report_err(local_err); | |
180 | } | |
181 | } | |
182 | ||
183 | /* | |
184 | * Notifies the user of the BlockBackend that migration has completed. qdev | |
185 | * devices can tighten their permissions in response (specifically revoke | |
186 | * shared write permissions that we needed for storage migration). | |
187 | * | |
188 | * If an error is returned, the VM cannot be allowed to be resumed. | |
189 | */ | |
190 | static void GRAPH_RDLOCK blk_root_activate(BdrvChild *child, Error **errp) | |
191 | { | |
192 | BlockBackend *blk = child->opaque; | |
193 | Error *local_err = NULL; | |
194 | uint64_t saved_shared_perm; | |
195 | ||
196 | if (!blk->disable_perm) { | |
197 | return; | |
198 | } | |
199 | ||
200 | blk->disable_perm = false; | |
201 | ||
202 | /* | |
203 | * blk->shared_perm contains the permissions we want to share once | |
204 | * migration is really completely done. For now, we need to share | |
205 | * all; but we also need to retain blk->shared_perm, which is | |
206 | * overwritten by a successful blk_set_perm() call. Save it and | |
207 | * restore it below. | |
208 | */ | |
209 | saved_shared_perm = blk->shared_perm; | |
210 | ||
211 | blk_set_perm_locked(blk, blk->perm, BLK_PERM_ALL, &local_err); | |
212 | if (local_err) { | |
213 | error_propagate(errp, local_err); | |
214 | blk->disable_perm = true; | |
215 | return; | |
216 | } | |
217 | blk->shared_perm = saved_shared_perm; | |
218 | ||
219 | if (runstate_check(RUN_STATE_INMIGRATE)) { | |
220 | /* Activation can happen when migration process is still active, for | |
221 | * example when nbd_server_add is called during non-shared storage | |
222 | * migration. Defer the shared_perm update to migration completion. */ | |
223 | if (!blk->vmsh) { | |
224 | blk->vmsh = qemu_add_vm_change_state_handler(blk_vm_state_changed, | |
225 | blk); | |
226 | } | |
227 | return; | |
228 | } | |
229 | ||
230 | blk_set_perm_locked(blk, blk->perm, blk->shared_perm, &local_err); | |
231 | if (local_err) { | |
232 | error_propagate(errp, local_err); | |
233 | blk->disable_perm = true; | |
234 | return; | |
235 | } | |
236 | } | |
237 | ||
238 | void blk_set_force_allow_inactivate(BlockBackend *blk) | |
239 | { | |
240 | GLOBAL_STATE_CODE(); | |
241 | blk->force_allow_inactivate = true; | |
242 | } | |
243 | ||
244 | static bool blk_can_inactivate(BlockBackend *blk) | |
245 | { | |
246 | /* If it is a guest device, inactivate is ok. */ | |
247 | if (blk->dev || blk_name(blk)[0]) { | |
248 | return true; | |
249 | } | |
250 | ||
251 | /* Inactivating means no more writes to the image can be done, | |
252 | * even if those writes would be changes invisible to the | |
253 | * guest. For block job BBs that satisfy this, we can just allow | |
254 | * it. This is the case for mirror job source, which is required | |
255 | * by libvirt non-shared block migration. */ | |
256 | if (!(blk->perm & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED))) { | |
257 | return true; | |
258 | } | |
259 | ||
260 | return blk->force_allow_inactivate; | |
261 | } | |
262 | ||
263 | static int GRAPH_RDLOCK blk_root_inactivate(BdrvChild *child) | |
264 | { | |
265 | BlockBackend *blk = child->opaque; | |
266 | ||
267 | if (blk->disable_perm) { | |
268 | return 0; | |
269 | } | |
270 | ||
271 | if (!blk_can_inactivate(blk)) { | |
272 | return -EPERM; | |
273 | } | |
274 | ||
275 | blk->disable_perm = true; | |
276 | if (blk->root) { | |
277 | bdrv_child_try_set_perm(blk->root, 0, BLK_PERM_ALL, &error_abort); | |
278 | } | |
279 | ||
280 | return 0; | |
281 | } | |
282 | ||
283 | static void blk_root_attach(BdrvChild *child) | |
284 | { | |
285 | BlockBackend *blk = child->opaque; | |
286 | BlockBackendAioNotifier *notifier; | |
287 | ||
288 | trace_blk_root_attach(child, blk, child->bs); | |
289 | ||
290 | QLIST_FOREACH(notifier, &blk->aio_notifiers, list) { | |
291 | bdrv_add_aio_context_notifier(child->bs, | |
292 | notifier->attached_aio_context, | |
293 | notifier->detach_aio_context, | |
294 | notifier->opaque); | |
295 | } | |
296 | } | |
297 | ||
298 | static void blk_root_detach(BdrvChild *child) | |
299 | { | |
300 | BlockBackend *blk = child->opaque; | |
301 | BlockBackendAioNotifier *notifier; | |
302 | ||
303 | trace_blk_root_detach(child, blk, child->bs); | |
304 | ||
305 | QLIST_FOREACH(notifier, &blk->aio_notifiers, list) { | |
306 | bdrv_remove_aio_context_notifier(child->bs, | |
307 | notifier->attached_aio_context, | |
308 | notifier->detach_aio_context, | |
309 | notifier->opaque); | |
310 | } | |
311 | } | |
312 | ||
313 | static AioContext *blk_root_get_parent_aio_context(BdrvChild *c) | |
314 | { | |
315 | BlockBackend *blk = c->opaque; | |
316 | IO_CODE(); | |
317 | ||
318 | return blk_get_aio_context(blk); | |
319 | } | |
320 | ||
321 | static const BdrvChildClass child_root = { | |
322 | .inherit_options = blk_root_inherit_options, | |
323 | ||
324 | .change_media = blk_root_change_media, | |
325 | .resize = blk_root_resize, | |
326 | .get_name = blk_root_get_name, | |
327 | .get_parent_desc = blk_root_get_parent_desc, | |
328 | ||
329 | .drained_begin = blk_root_drained_begin, | |
330 | .drained_poll = blk_root_drained_poll, | |
331 | .drained_end = blk_root_drained_end, | |
332 | ||
333 | .activate = blk_root_activate, | |
334 | .inactivate = blk_root_inactivate, | |
335 | ||
336 | .attach = blk_root_attach, | |
337 | .detach = blk_root_detach, | |
338 | ||
339 | .change_aio_ctx = blk_root_change_aio_ctx, | |
340 | ||
341 | .get_parent_aio_context = blk_root_get_parent_aio_context, | |
342 | }; | |
343 | ||
344 | /* | |
345 | * Create a new BlockBackend with a reference count of one. | |
346 | * | |
347 | * @perm is a bitmasks of BLK_PERM_* constants which describes the permissions | |
348 | * to request for a block driver node that is attached to this BlockBackend. | |
349 | * @shared_perm is a bitmask which describes which permissions may be granted | |
350 | * to other users of the attached node. | |
351 | * Both sets of permissions can be changed later using blk_set_perm(). | |
352 | * | |
353 | * Return the new BlockBackend on success, null on failure. | |
354 | */ | |
355 | BlockBackend *blk_new(AioContext *ctx, uint64_t perm, uint64_t shared_perm) | |
356 | { | |
357 | BlockBackend *blk; | |
358 | ||
359 | GLOBAL_STATE_CODE(); | |
360 | ||
361 | blk = g_new0(BlockBackend, 1); | |
362 | blk->refcnt = 1; | |
363 | blk->ctx = ctx; | |
364 | blk->perm = perm; | |
365 | blk->shared_perm = shared_perm; | |
366 | blk_set_enable_write_cache(blk, true); | |
367 | ||
368 | blk->on_read_error = BLOCKDEV_ON_ERROR_REPORT; | |
369 | blk->on_write_error = BLOCKDEV_ON_ERROR_ENOSPC; | |
370 | ||
371 | block_acct_init(&blk->stats); | |
372 | ||
373 | qemu_mutex_init(&blk->queued_requests_lock); | |
374 | qemu_co_queue_init(&blk->queued_requests); | |
375 | notifier_list_init(&blk->remove_bs_notifiers); | |
376 | notifier_list_init(&blk->insert_bs_notifiers); | |
377 | QLIST_INIT(&blk->aio_notifiers); | |
378 | ||
379 | QTAILQ_INSERT_TAIL(&block_backends, blk, link); | |
380 | return blk; | |
381 | } | |
382 | ||
383 | /* | |
384 | * Create a new BlockBackend connected to an existing BlockDriverState. | |
385 | * | |
386 | * @perm is a bitmasks of BLK_PERM_* constants which describes the | |
387 | * permissions to request for @bs that is attached to this | |
388 | * BlockBackend. @shared_perm is a bitmask which describes which | |
389 | * permissions may be granted to other users of the attached node. | |
390 | * Both sets of permissions can be changed later using blk_set_perm(). | |
391 | * | |
392 | * Return the new BlockBackend on success, null on failure. | |
393 | */ | |
394 | BlockBackend *blk_new_with_bs(BlockDriverState *bs, uint64_t perm, | |
395 | uint64_t shared_perm, Error **errp) | |
396 | { | |
397 | BlockBackend *blk = blk_new(bdrv_get_aio_context(bs), perm, shared_perm); | |
398 | ||
399 | GLOBAL_STATE_CODE(); | |
400 | ||
401 | if (blk_insert_bs(blk, bs, errp) < 0) { | |
402 | blk_unref(blk); | |
403 | return NULL; | |
404 | } | |
405 | return blk; | |
406 | } | |
407 | ||
408 | /* | |
409 | * Creates a new BlockBackend, opens a new BlockDriverState, and connects both. | |
410 | * By default, the new BlockBackend is in the main AioContext, but if the | |
411 | * parameters connect it with any existing node in a different AioContext, it | |
412 | * may end up there instead. | |
413 | * | |
414 | * Just as with bdrv_open(), after having called this function the reference to | |
415 | * @options belongs to the block layer (even on failure). | |
416 | * | |
417 | * TODO: Remove @filename and @flags; it should be possible to specify a whole | |
418 | * BDS tree just by specifying the @options QDict (or @reference, | |
419 | * alternatively). At the time of adding this function, this is not possible, | |
420 | * though, so callers of this function have to be able to specify @filename and | |
421 | * @flags. | |
422 | */ | |
423 | BlockBackend *blk_new_open(const char *filename, const char *reference, | |
424 | QDict *options, int flags, Error **errp) | |
425 | { | |
426 | BlockBackend *blk; | |
427 | BlockDriverState *bs; | |
428 | uint64_t perm = 0; | |
429 | uint64_t shared = BLK_PERM_ALL; | |
430 | ||
431 | GLOBAL_STATE_CODE(); | |
432 | ||
433 | /* | |
434 | * blk_new_open() is mainly used in .bdrv_create implementations and the | |
435 | * tools where sharing isn't a major concern because the BDS stays private | |
436 | * and the file is generally not supposed to be used by a second process, | |
437 | * so we just request permission according to the flags. | |
438 | * | |
439 | * The exceptions are xen_disk and blockdev_init(); in these cases, the | |
440 | * caller of blk_new_open() doesn't make use of the permissions, but they | |
441 | * shouldn't hurt either. We can still share everything here because the | |
442 | * guest devices will add their own blockers if they can't share. | |
443 | */ | |
444 | if ((flags & BDRV_O_NO_IO) == 0) { | |
445 | perm |= BLK_PERM_CONSISTENT_READ; | |
446 | if (flags & BDRV_O_RDWR) { | |
447 | perm |= BLK_PERM_WRITE; | |
448 | } | |
449 | } | |
450 | if (flags & BDRV_O_RESIZE) { | |
451 | perm |= BLK_PERM_RESIZE; | |
452 | } | |
453 | if (flags & BDRV_O_NO_SHARE) { | |
454 | shared = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED; | |
455 | } | |
456 | ||
457 | bs = bdrv_open(filename, reference, options, flags, errp); | |
458 | if (!bs) { | |
459 | return NULL; | |
460 | } | |
461 | ||
462 | /* bdrv_open() could have moved bs to a different AioContext */ | |
463 | blk = blk_new(bdrv_get_aio_context(bs), perm, shared); | |
464 | blk->perm = perm; | |
465 | blk->shared_perm = shared; | |
466 | ||
467 | blk_insert_bs(blk, bs, errp); | |
468 | bdrv_unref(bs); | |
469 | ||
470 | if (!blk->root) { | |
471 | blk_unref(blk); | |
472 | return NULL; | |
473 | } | |
474 | ||
475 | return blk; | |
476 | } | |
477 | ||
478 | static void blk_delete(BlockBackend *blk) | |
479 | { | |
480 | assert(!blk->refcnt); | |
481 | assert(!blk->name); | |
482 | assert(!blk->dev); | |
483 | if (blk->public.throttle_group_member.throttle_state) { | |
484 | blk_io_limits_disable(blk); | |
485 | } | |
486 | if (blk->root) { | |
487 | blk_remove_bs(blk); | |
488 | } | |
489 | if (blk->vmsh) { | |
490 | qemu_del_vm_change_state_handler(blk->vmsh); | |
491 | blk->vmsh = NULL; | |
492 | } | |
493 | assert(QLIST_EMPTY(&blk->remove_bs_notifiers.notifiers)); | |
494 | assert(QLIST_EMPTY(&blk->insert_bs_notifiers.notifiers)); | |
495 | assert(QLIST_EMPTY(&blk->aio_notifiers)); | |
496 | assert(qemu_co_queue_empty(&blk->queued_requests)); | |
497 | qemu_mutex_destroy(&blk->queued_requests_lock); | |
498 | QTAILQ_REMOVE(&block_backends, blk, link); | |
499 | drive_info_del(blk->legacy_dinfo); | |
500 | block_acct_cleanup(&blk->stats); | |
501 | g_free(blk); | |
502 | } | |
503 | ||
504 | static void drive_info_del(DriveInfo *dinfo) | |
505 | { | |
506 | if (!dinfo) { | |
507 | return; | |
508 | } | |
509 | qemu_opts_del(dinfo->opts); | |
510 | g_free(dinfo); | |
511 | } | |
512 | ||
513 | int blk_get_refcnt(BlockBackend *blk) | |
514 | { | |
515 | GLOBAL_STATE_CODE(); | |
516 | return blk ? blk->refcnt : 0; | |
517 | } | |
518 | ||
519 | /* | |
520 | * Increment @blk's reference count. | |
521 | * @blk must not be null. | |
522 | */ | |
523 | void blk_ref(BlockBackend *blk) | |
524 | { | |
525 | assert(blk->refcnt > 0); | |
526 | GLOBAL_STATE_CODE(); | |
527 | blk->refcnt++; | |
528 | } | |
529 | ||
530 | /* | |
531 | * Decrement @blk's reference count. | |
532 | * If this drops it to zero, destroy @blk. | |
533 | * For convenience, do nothing if @blk is null. | |
534 | */ | |
535 | void blk_unref(BlockBackend *blk) | |
536 | { | |
537 | GLOBAL_STATE_CODE(); | |
538 | if (blk) { | |
539 | assert(blk->refcnt > 0); | |
540 | if (blk->refcnt > 1) { | |
541 | blk->refcnt--; | |
542 | } else { | |
543 | blk_drain(blk); | |
544 | /* blk_drain() cannot resurrect blk, nobody held a reference */ | |
545 | assert(blk->refcnt == 1); | |
546 | blk->refcnt = 0; | |
547 | blk_delete(blk); | |
548 | } | |
549 | } | |
550 | } | |
551 | ||
552 | /* | |
553 | * Behaves similarly to blk_next() but iterates over all BlockBackends, even the | |
554 | * ones which are hidden (i.e. are not referenced by the monitor). | |
555 | */ | |
556 | BlockBackend *blk_all_next(BlockBackend *blk) | |
557 | { | |
558 | GLOBAL_STATE_CODE(); | |
559 | return blk ? QTAILQ_NEXT(blk, link) | |
560 | : QTAILQ_FIRST(&block_backends); | |
561 | } | |
562 | ||
563 | void blk_remove_all_bs(void) | |
564 | { | |
565 | BlockBackend *blk = NULL; | |
566 | ||
567 | GLOBAL_STATE_CODE(); | |
568 | ||
569 | while ((blk = blk_all_next(blk)) != NULL) { | |
570 | if (blk->root) { | |
571 | blk_remove_bs(blk); | |
572 | } | |
573 | } | |
574 | } | |
575 | ||
576 | /* | |
577 | * Return the monitor-owned BlockBackend after @blk. | |
578 | * If @blk is null, return the first one. | |
579 | * Else, return @blk's next sibling, which may be null. | |
580 | * | |
581 | * To iterate over all BlockBackends, do | |
582 | * for (blk = blk_next(NULL); blk; blk = blk_next(blk)) { | |
583 | * ... | |
584 | * } | |
585 | */ | |
586 | BlockBackend *blk_next(BlockBackend *blk) | |
587 | { | |
588 | GLOBAL_STATE_CODE(); | |
589 | return blk ? QTAILQ_NEXT(blk, monitor_link) | |
590 | : QTAILQ_FIRST(&monitor_block_backends); | |
591 | } | |
592 | ||
593 | /* Iterates over all top-level BlockDriverStates, i.e. BDSs that are owned by | |
594 | * the monitor or attached to a BlockBackend */ | |
595 | BlockDriverState *bdrv_next(BdrvNextIterator *it) | |
596 | { | |
597 | BlockDriverState *bs, *old_bs; | |
598 | ||
599 | /* Must be called from the main loop */ | |
600 | assert(qemu_get_current_aio_context() == qemu_get_aio_context()); | |
601 | ||
602 | /* First, return all root nodes of BlockBackends. In order to avoid | |
603 | * returning a BDS twice when multiple BBs refer to it, we only return it | |
604 | * if the BB is the first one in the parent list of the BDS. */ | |
605 | if (it->phase == BDRV_NEXT_BACKEND_ROOTS) { | |
606 | BlockBackend *old_blk = it->blk; | |
607 | ||
608 | old_bs = old_blk ? blk_bs(old_blk) : NULL; | |
609 | ||
610 | do { | |
611 | it->blk = blk_all_next(it->blk); | |
612 | bs = it->blk ? blk_bs(it->blk) : NULL; | |
613 | } while (it->blk && (bs == NULL || bdrv_first_blk(bs) != it->blk)); | |
614 | ||
615 | if (it->blk) { | |
616 | blk_ref(it->blk); | |
617 | } | |
618 | blk_unref(old_blk); | |
619 | ||
620 | if (bs) { | |
621 | bdrv_ref(bs); | |
622 | bdrv_unref(old_bs); | |
623 | return bs; | |
624 | } | |
625 | it->phase = BDRV_NEXT_MONITOR_OWNED; | |
626 | } else { | |
627 | old_bs = it->bs; | |
628 | } | |
629 | ||
630 | /* Then return the monitor-owned BDSes without a BB attached. Ignore all | |
631 | * BDSes that are attached to a BlockBackend here; they have been handled | |
632 | * by the above block already */ | |
633 | do { | |
634 | it->bs = bdrv_next_monitor_owned(it->bs); | |
635 | bs = it->bs; | |
636 | } while (bs && bdrv_has_blk(bs)); | |
637 | ||
638 | if (bs) { | |
639 | bdrv_ref(bs); | |
640 | } | |
641 | bdrv_unref(old_bs); | |
642 | ||
643 | return bs; | |
644 | } | |
645 | ||
646 | static void bdrv_next_reset(BdrvNextIterator *it) | |
647 | { | |
648 | *it = (BdrvNextIterator) { | |
649 | .phase = BDRV_NEXT_BACKEND_ROOTS, | |
650 | }; | |
651 | } | |
652 | ||
653 | BlockDriverState *bdrv_first(BdrvNextIterator *it) | |
654 | { | |
655 | GLOBAL_STATE_CODE(); | |
656 | bdrv_next_reset(it); | |
657 | return bdrv_next(it); | |
658 | } | |
659 | ||
660 | /* Must be called when aborting a bdrv_next() iteration before | |
661 | * bdrv_next() returns NULL */ | |
662 | void bdrv_next_cleanup(BdrvNextIterator *it) | |
663 | { | |
664 | /* Must be called from the main loop */ | |
665 | assert(qemu_get_current_aio_context() == qemu_get_aio_context()); | |
666 | ||
667 | if (it->phase == BDRV_NEXT_BACKEND_ROOTS) { | |
668 | if (it->blk) { | |
669 | bdrv_unref(blk_bs(it->blk)); | |
670 | blk_unref(it->blk); | |
671 | } | |
672 | } else { | |
673 | bdrv_unref(it->bs); | |
674 | } | |
675 | ||
676 | bdrv_next_reset(it); | |
677 | } | |
678 | ||
679 | /* | |
680 | * Add a BlockBackend into the list of backends referenced by the monitor, with | |
681 | * the given @name acting as the handle for the monitor. | |
682 | * Strictly for use by blockdev.c. | |
683 | * | |
684 | * @name must not be null or empty. | |
685 | * | |
686 | * Returns true on success and false on failure. In the latter case, an Error | |
687 | * object is returned through @errp. | |
688 | */ | |
689 | bool monitor_add_blk(BlockBackend *blk, const char *name, Error **errp) | |
690 | { | |
691 | assert(!blk->name); | |
692 | assert(name && name[0]); | |
693 | GLOBAL_STATE_CODE(); | |
694 | ||
695 | if (!id_wellformed(name)) { | |
696 | error_setg(errp, "Invalid device name"); | |
697 | return false; | |
698 | } | |
699 | if (blk_by_name(name)) { | |
700 | error_setg(errp, "Device with id '%s' already exists", name); | |
701 | return false; | |
702 | } | |
703 | if (bdrv_find_node(name)) { | |
704 | error_setg(errp, | |
705 | "Device name '%s' conflicts with an existing node name", | |
706 | name); | |
707 | return false; | |
708 | } | |
709 | ||
710 | blk->name = g_strdup(name); | |
711 | QTAILQ_INSERT_TAIL(&monitor_block_backends, blk, monitor_link); | |
712 | return true; | |
713 | } | |
714 | ||
715 | /* | |
716 | * Remove a BlockBackend from the list of backends referenced by the monitor. | |
717 | * Strictly for use by blockdev.c. | |
718 | */ | |
719 | void monitor_remove_blk(BlockBackend *blk) | |
720 | { | |
721 | GLOBAL_STATE_CODE(); | |
722 | ||
723 | if (!blk->name) { | |
724 | return; | |
725 | } | |
726 | ||
727 | QTAILQ_REMOVE(&monitor_block_backends, blk, monitor_link); | |
728 | g_free(blk->name); | |
729 | blk->name = NULL; | |
730 | } | |
731 | ||
732 | /* | |
733 | * Return @blk's name, a non-null string. | |
734 | * Returns an empty string iff @blk is not referenced by the monitor. | |
735 | */ | |
736 | const char *blk_name(const BlockBackend *blk) | |
737 | { | |
738 | IO_CODE(); | |
739 | return blk->name ?: ""; | |
740 | } | |
741 | ||
742 | /* | |
743 | * Return the BlockBackend with name @name if it exists, else null. | |
744 | * @name must not be null. | |
745 | */ | |
746 | BlockBackend *blk_by_name(const char *name) | |
747 | { | |
748 | BlockBackend *blk = NULL; | |
749 | ||
750 | GLOBAL_STATE_CODE(); | |
751 | assert(name); | |
752 | while ((blk = blk_next(blk)) != NULL) { | |
753 | if (!strcmp(name, blk->name)) { | |
754 | return blk; | |
755 | } | |
756 | } | |
757 | return NULL; | |
758 | } | |
759 | ||
760 | /* | |
761 | * Return the BlockDriverState attached to @blk if any, else null. | |
762 | */ | |
763 | BlockDriverState *blk_bs(BlockBackend *blk) | |
764 | { | |
765 | IO_CODE(); | |
766 | return blk->root ? blk->root->bs : NULL; | |
767 | } | |
768 | ||
769 | static BlockBackend * GRAPH_RDLOCK bdrv_first_blk(BlockDriverState *bs) | |
770 | { | |
771 | BdrvChild *child; | |
772 | ||
773 | GLOBAL_STATE_CODE(); | |
774 | assert_bdrv_graph_readable(); | |
775 | ||
776 | QLIST_FOREACH(child, &bs->parents, next_parent) { | |
777 | if (child->klass == &child_root) { | |
778 | return child->opaque; | |
779 | } | |
780 | } | |
781 | ||
782 | return NULL; | |
783 | } | |
784 | ||
785 | /* | |
786 | * Returns true if @bs has an associated BlockBackend. | |
787 | */ | |
788 | bool bdrv_has_blk(BlockDriverState *bs) | |
789 | { | |
790 | GLOBAL_STATE_CODE(); | |
791 | return bdrv_first_blk(bs) != NULL; | |
792 | } | |
793 | ||
794 | /* | |
795 | * Returns true if @bs has only BlockBackends as parents. | |
796 | */ | |
797 | bool bdrv_is_root_node(BlockDriverState *bs) | |
798 | { | |
799 | BdrvChild *c; | |
800 | ||
801 | GLOBAL_STATE_CODE(); | |
802 | assert_bdrv_graph_readable(); | |
803 | ||
804 | QLIST_FOREACH(c, &bs->parents, next_parent) { | |
805 | if (c->klass != &child_root) { | |
806 | return false; | |
807 | } | |
808 | } | |
809 | ||
810 | return true; | |
811 | } | |
812 | ||
813 | /* | |
814 | * Return @blk's DriveInfo if any, else null. | |
815 | */ | |
816 | DriveInfo *blk_legacy_dinfo(BlockBackend *blk) | |
817 | { | |
818 | GLOBAL_STATE_CODE(); | |
819 | return blk->legacy_dinfo; | |
820 | } | |
821 | ||
822 | /* | |
823 | * Set @blk's DriveInfo to @dinfo, and return it. | |
824 | * @blk must not have a DriveInfo set already. | |
825 | * No other BlockBackend may have the same DriveInfo set. | |
826 | */ | |
827 | DriveInfo *blk_set_legacy_dinfo(BlockBackend *blk, DriveInfo *dinfo) | |
828 | { | |
829 | assert(!blk->legacy_dinfo); | |
830 | GLOBAL_STATE_CODE(); | |
831 | return blk->legacy_dinfo = dinfo; | |
832 | } | |
833 | ||
834 | /* | |
835 | * Return the BlockBackend with DriveInfo @dinfo. | |
836 | * It must exist. | |
837 | */ | |
838 | BlockBackend *blk_by_legacy_dinfo(DriveInfo *dinfo) | |
839 | { | |
840 | BlockBackend *blk = NULL; | |
841 | GLOBAL_STATE_CODE(); | |
842 | ||
843 | while ((blk = blk_next(blk)) != NULL) { | |
844 | if (blk->legacy_dinfo == dinfo) { | |
845 | return blk; | |
846 | } | |
847 | } | |
848 | abort(); | |
849 | } | |
850 | ||
851 | /* | |
852 | * Returns a pointer to the publicly accessible fields of @blk. | |
853 | */ | |
854 | BlockBackendPublic *blk_get_public(BlockBackend *blk) | |
855 | { | |
856 | GLOBAL_STATE_CODE(); | |
857 | return &blk->public; | |
858 | } | |
859 | ||
860 | /* | |
861 | * Returns a BlockBackend given the associated @public fields. | |
862 | */ | |
863 | BlockBackend *blk_by_public(BlockBackendPublic *public) | |
864 | { | |
865 | GLOBAL_STATE_CODE(); | |
866 | return container_of(public, BlockBackend, public); | |
867 | } | |
868 | ||
869 | /* | |
870 | * Disassociates the currently associated BlockDriverState from @blk. | |
871 | */ | |
872 | void blk_remove_bs(BlockBackend *blk) | |
873 | { | |
874 | ThrottleGroupMember *tgm = &blk->public.throttle_group_member; | |
875 | BdrvChild *root; | |
876 | ||
877 | GLOBAL_STATE_CODE(); | |
878 | ||
879 | notifier_list_notify(&blk->remove_bs_notifiers, blk); | |
880 | if (tgm->throttle_state) { | |
881 | BlockDriverState *bs = blk_bs(blk); | |
882 | ||
883 | /* | |
884 | * Take a ref in case blk_bs() changes across bdrv_drained_begin(), for | |
885 | * example, if a temporary filter node is removed by a blockjob. | |
886 | */ | |
887 | bdrv_ref(bs); | |
888 | bdrv_drained_begin(bs); | |
889 | throttle_group_detach_aio_context(tgm); | |
890 | throttle_group_attach_aio_context(tgm, qemu_get_aio_context()); | |
891 | bdrv_drained_end(bs); | |
892 | bdrv_unref(bs); | |
893 | } | |
894 | ||
895 | blk_update_root_state(blk); | |
896 | ||
897 | /* bdrv_root_unref_child() will cause blk->root to become stale and may | |
898 | * switch to a completion coroutine later on. Let's drain all I/O here | |
899 | * to avoid that and a potential QEMU crash. | |
900 | */ | |
901 | blk_drain(blk); | |
902 | root = blk->root; | |
903 | blk->root = NULL; | |
904 | ||
905 | bdrv_graph_wrlock(); | |
906 | bdrv_root_unref_child(root); | |
907 | bdrv_graph_wrunlock(); | |
908 | } | |
909 | ||
910 | /* | |
911 | * Associates a new BlockDriverState with @blk. | |
912 | */ | |
913 | int blk_insert_bs(BlockBackend *blk, BlockDriverState *bs, Error **errp) | |
914 | { | |
915 | ThrottleGroupMember *tgm = &blk->public.throttle_group_member; | |
916 | ||
917 | GLOBAL_STATE_CODE(); | |
918 | bdrv_ref(bs); | |
919 | bdrv_graph_wrlock(); | |
920 | blk->root = bdrv_root_attach_child(bs, "root", &child_root, | |
921 | BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, | |
922 | blk->perm, blk->shared_perm, | |
923 | blk, errp); | |
924 | bdrv_graph_wrunlock(); | |
925 | if (blk->root == NULL) { | |
926 | return -EPERM; | |
927 | } | |
928 | ||
929 | notifier_list_notify(&blk->insert_bs_notifiers, blk); | |
930 | if (tgm->throttle_state) { | |
931 | throttle_group_detach_aio_context(tgm); | |
932 | throttle_group_attach_aio_context(tgm, bdrv_get_aio_context(bs)); | |
933 | } | |
934 | ||
935 | return 0; | |
936 | } | |
937 | ||
938 | /* | |
939 | * Change BlockDriverState associated with @blk. | |
940 | */ | |
941 | int blk_replace_bs(BlockBackend *blk, BlockDriverState *new_bs, Error **errp) | |
942 | { | |
943 | GLOBAL_STATE_CODE(); | |
944 | return bdrv_replace_child_bs(blk->root, new_bs, errp); | |
945 | } | |
946 | ||
947 | /* | |
948 | * Sets the permission bitmasks that the user of the BlockBackend needs. | |
949 | */ | |
950 | static int coroutine_mixed_fn GRAPH_RDLOCK | |
951 | blk_set_perm_locked(BlockBackend *blk, uint64_t perm, uint64_t shared_perm, | |
952 | Error **errp) | |
953 | { | |
954 | int ret; | |
955 | GLOBAL_STATE_CODE(); | |
956 | ||
957 | if (blk->root && !blk->disable_perm) { | |
958 | ret = bdrv_child_try_set_perm(blk->root, perm, shared_perm, errp); | |
959 | if (ret < 0) { | |
960 | return ret; | |
961 | } | |
962 | } | |
963 | ||
964 | blk->perm = perm; | |
965 | blk->shared_perm = shared_perm; | |
966 | ||
967 | return 0; | |
968 | } | |
969 | ||
970 | int blk_set_perm(BlockBackend *blk, uint64_t perm, uint64_t shared_perm, | |
971 | Error **errp) | |
972 | { | |
973 | GLOBAL_STATE_CODE(); | |
974 | GRAPH_RDLOCK_GUARD_MAINLOOP(); | |
975 | ||
976 | return blk_set_perm_locked(blk, perm, shared_perm, errp); | |
977 | } | |
978 | ||
979 | void blk_get_perm(BlockBackend *blk, uint64_t *perm, uint64_t *shared_perm) | |
980 | { | |
981 | GLOBAL_STATE_CODE(); | |
982 | *perm = blk->perm; | |
983 | *shared_perm = blk->shared_perm; | |
984 | } | |
985 | ||
986 | /* | |
987 | * Attach device model @dev to @blk. | |
988 | * Return 0 on success, -EBUSY when a device model is attached already. | |
989 | */ | |
990 | int blk_attach_dev(BlockBackend *blk, DeviceState *dev) | |
991 | { | |
992 | GLOBAL_STATE_CODE(); | |
993 | if (blk->dev) { | |
994 | return -EBUSY; | |
995 | } | |
996 | ||
997 | /* While migration is still incoming, we don't need to apply the | |
998 | * permissions of guest device BlockBackends. We might still have a block | |
999 | * job or NBD server writing to the image for storage migration. */ | |
1000 | if (runstate_check(RUN_STATE_INMIGRATE)) { | |
1001 | blk->disable_perm = true; | |
1002 | } | |
1003 | ||
1004 | blk_ref(blk); | |
1005 | blk->dev = dev; | |
1006 | blk_iostatus_reset(blk); | |
1007 | ||
1008 | return 0; | |
1009 | } | |
1010 | ||
1011 | /* | |
1012 | * Detach device model @dev from @blk. | |
1013 | * @dev must be currently attached to @blk. | |
1014 | */ | |
1015 | void blk_detach_dev(BlockBackend *blk, DeviceState *dev) | |
1016 | { | |
1017 | assert(blk->dev == dev); | |
1018 | GLOBAL_STATE_CODE(); | |
1019 | blk->dev = NULL; | |
1020 | blk->dev_ops = NULL; | |
1021 | blk->dev_opaque = NULL; | |
1022 | blk_set_perm(blk, 0, BLK_PERM_ALL, &error_abort); | |
1023 | blk_unref(blk); | |
1024 | } | |
1025 | ||
1026 | /* | |
1027 | * Return the device model attached to @blk if any, else null. | |
1028 | */ | |
1029 | DeviceState *blk_get_attached_dev(BlockBackend *blk) | |
1030 | { | |
1031 | GLOBAL_STATE_CODE(); | |
1032 | return blk->dev; | |
1033 | } | |
1034 | ||
1035 | /* Return the qdev ID, or if no ID is assigned the QOM path, of the block | |
1036 | * device attached to the BlockBackend. */ | |
1037 | char *blk_get_attached_dev_id(BlockBackend *blk) | |
1038 | { | |
1039 | DeviceState *dev = blk->dev; | |
1040 | IO_CODE(); | |
1041 | ||
1042 | if (!dev) { | |
1043 | return g_strdup(""); | |
1044 | } else if (dev->id) { | |
1045 | return g_strdup(dev->id); | |
1046 | } | |
1047 | ||
1048 | return object_get_canonical_path(OBJECT(dev)) ?: g_strdup(""); | |
1049 | } | |
1050 | ||
1051 | /* | |
1052 | * Return the BlockBackend which has the device model @dev attached if it | |
1053 | * exists, else null. | |
1054 | * | |
1055 | * @dev must not be null. | |
1056 | */ | |
1057 | BlockBackend *blk_by_dev(void *dev) | |
1058 | { | |
1059 | BlockBackend *blk = NULL; | |
1060 | ||
1061 | GLOBAL_STATE_CODE(); | |
1062 | ||
1063 | assert(dev != NULL); | |
1064 | while ((blk = blk_all_next(blk)) != NULL) { | |
1065 | if (blk->dev == dev) { | |
1066 | return blk; | |
1067 | } | |
1068 | } | |
1069 | return NULL; | |
1070 | } | |
1071 | ||
1072 | /* | |
1073 | * Set @blk's device model callbacks to @ops. | |
1074 | * @opaque is the opaque argument to pass to the callbacks. | |
1075 | * This is for use by device models. | |
1076 | */ | |
1077 | void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops, | |
1078 | void *opaque) | |
1079 | { | |
1080 | GLOBAL_STATE_CODE(); | |
1081 | blk->dev_ops = ops; | |
1082 | blk->dev_opaque = opaque; | |
1083 | ||
1084 | /* Are we currently quiesced? Should we enforce this right now? */ | |
1085 | if (qatomic_read(&blk->quiesce_counter) && ops && ops->drained_begin) { | |
1086 | ops->drained_begin(opaque); | |
1087 | } | |
1088 | } | |
1089 | ||
1090 | /* | |
1091 | * Notify @blk's attached device model of media change. | |
1092 | * | |
1093 | * If @load is true, notify of media load. This action can fail, meaning that | |
1094 | * the medium cannot be loaded. @errp is set then. | |
1095 | * | |
1096 | * If @load is false, notify of media eject. This can never fail. | |
1097 | * | |
1098 | * Also send DEVICE_TRAY_MOVED events as appropriate. | |
1099 | */ | |
1100 | void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error **errp) | |
1101 | { | |
1102 | GLOBAL_STATE_CODE(); | |
1103 | if (blk->dev_ops && blk->dev_ops->change_media_cb) { | |
1104 | bool tray_was_open, tray_is_open; | |
1105 | Error *local_err = NULL; | |
1106 | ||
1107 | tray_was_open = blk_dev_is_tray_open(blk); | |
1108 | blk->dev_ops->change_media_cb(blk->dev_opaque, load, &local_err); | |
1109 | if (local_err) { | |
1110 | assert(load == true); | |
1111 | error_propagate(errp, local_err); | |
1112 | return; | |
1113 | } | |
1114 | tray_is_open = blk_dev_is_tray_open(blk); | |
1115 | ||
1116 | if (tray_was_open != tray_is_open) { | |
1117 | char *id = blk_get_attached_dev_id(blk); | |
1118 | qapi_event_send_device_tray_moved(blk_name(blk), id, tray_is_open); | |
1119 | g_free(id); | |
1120 | } | |
1121 | } | |
1122 | } | |
1123 | ||
1124 | static void blk_root_change_media(BdrvChild *child, bool load) | |
1125 | { | |
1126 | blk_dev_change_media_cb(child->opaque, load, NULL); | |
1127 | } | |
1128 | ||
1129 | /* | |
1130 | * Does @blk's attached device model have removable media? | |
1131 | * %true if no device model is attached. | |
1132 | */ | |
1133 | bool blk_dev_has_removable_media(BlockBackend *blk) | |
1134 | { | |
1135 | GLOBAL_STATE_CODE(); | |
1136 | return !blk->dev || (blk->dev_ops && blk->dev_ops->change_media_cb); | |
1137 | } | |
1138 | ||
1139 | /* | |
1140 | * Does @blk's attached device model have a tray? | |
1141 | */ | |
1142 | bool blk_dev_has_tray(BlockBackend *blk) | |
1143 | { | |
1144 | IO_CODE(); | |
1145 | return blk->dev_ops && blk->dev_ops->is_tray_open; | |
1146 | } | |
1147 | ||
1148 | /* | |
1149 | * Notify @blk's attached device model of a media eject request. | |
1150 | * If @force is true, the medium is about to be yanked out forcefully. | |
1151 | */ | |
1152 | void blk_dev_eject_request(BlockBackend *blk, bool force) | |
1153 | { | |
1154 | GLOBAL_STATE_CODE(); | |
1155 | if (blk->dev_ops && blk->dev_ops->eject_request_cb) { | |
1156 | blk->dev_ops->eject_request_cb(blk->dev_opaque, force); | |
1157 | } | |
1158 | } | |
1159 | ||
1160 | /* | |
1161 | * Does @blk's attached device model have a tray, and is it open? | |
1162 | */ | |
1163 | bool blk_dev_is_tray_open(BlockBackend *blk) | |
1164 | { | |
1165 | IO_CODE(); | |
1166 | if (blk_dev_has_tray(blk)) { | |
1167 | return blk->dev_ops->is_tray_open(blk->dev_opaque); | |
1168 | } | |
1169 | return false; | |
1170 | } | |
1171 | ||
1172 | /* | |
1173 | * Does @blk's attached device model have the medium locked? | |
1174 | * %false if the device model has no such lock. | |
1175 | */ | |
1176 | bool blk_dev_is_medium_locked(BlockBackend *blk) | |
1177 | { | |
1178 | GLOBAL_STATE_CODE(); | |
1179 | if (blk->dev_ops && blk->dev_ops->is_medium_locked) { | |
1180 | return blk->dev_ops->is_medium_locked(blk->dev_opaque); | |
1181 | } | |
1182 | return false; | |
1183 | } | |
1184 | ||
1185 | /* | |
1186 | * Notify @blk's attached device model of a backend size change. | |
1187 | */ | |
1188 | static void blk_root_resize(BdrvChild *child) | |
1189 | { | |
1190 | BlockBackend *blk = child->opaque; | |
1191 | ||
1192 | if (blk->dev_ops && blk->dev_ops->resize_cb) { | |
1193 | blk->dev_ops->resize_cb(blk->dev_opaque); | |
1194 | } | |
1195 | } | |
1196 | ||
1197 | void blk_iostatus_enable(BlockBackend *blk) | |
1198 | { | |
1199 | GLOBAL_STATE_CODE(); | |
1200 | blk->iostatus_enabled = true; | |
1201 | blk->iostatus = BLOCK_DEVICE_IO_STATUS_OK; | |
1202 | } | |
1203 | ||
1204 | /* The I/O status is only enabled if the drive explicitly | |
1205 | * enables it _and_ the VM is configured to stop on errors */ | |
1206 | bool blk_iostatus_is_enabled(const BlockBackend *blk) | |
1207 | { | |
1208 | IO_CODE(); | |
1209 | return (blk->iostatus_enabled && | |
1210 | (blk->on_write_error == BLOCKDEV_ON_ERROR_ENOSPC || | |
1211 | blk->on_write_error == BLOCKDEV_ON_ERROR_STOP || | |
1212 | blk->on_read_error == BLOCKDEV_ON_ERROR_STOP)); | |
1213 | } | |
1214 | ||
1215 | BlockDeviceIoStatus blk_iostatus(const BlockBackend *blk) | |
1216 | { | |
1217 | GLOBAL_STATE_CODE(); | |
1218 | return blk->iostatus; | |
1219 | } | |
1220 | ||
1221 | void blk_iostatus_disable(BlockBackend *blk) | |
1222 | { | |
1223 | GLOBAL_STATE_CODE(); | |
1224 | blk->iostatus_enabled = false; | |
1225 | } | |
1226 | ||
1227 | void blk_iostatus_reset(BlockBackend *blk) | |
1228 | { | |
1229 | GLOBAL_STATE_CODE(); | |
1230 | if (blk_iostatus_is_enabled(blk)) { | |
1231 | blk->iostatus = BLOCK_DEVICE_IO_STATUS_OK; | |
1232 | } | |
1233 | } | |
1234 | ||
1235 | void blk_iostatus_set_err(BlockBackend *blk, int error) | |
1236 | { | |
1237 | IO_CODE(); | |
1238 | assert(blk_iostatus_is_enabled(blk)); | |
1239 | if (blk->iostatus == BLOCK_DEVICE_IO_STATUS_OK) { | |
1240 | blk->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE : | |
1241 | BLOCK_DEVICE_IO_STATUS_FAILED; | |
1242 | } | |
1243 | } | |
1244 | ||
1245 | void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow) | |
1246 | { | |
1247 | IO_CODE(); | |
1248 | blk->allow_write_beyond_eof = allow; | |
1249 | } | |
1250 | ||
1251 | void blk_set_allow_aio_context_change(BlockBackend *blk, bool allow) | |
1252 | { | |
1253 | IO_CODE(); | |
1254 | blk->allow_aio_context_change = allow; | |
1255 | } | |
1256 | ||
1257 | void blk_set_disable_request_queuing(BlockBackend *blk, bool disable) | |
1258 | { | |
1259 | IO_CODE(); | |
1260 | qatomic_set(&blk->disable_request_queuing, disable); | |
1261 | } | |
1262 | ||
1263 | static int coroutine_fn GRAPH_RDLOCK | |
1264 | blk_check_byte_request(BlockBackend *blk, int64_t offset, int64_t bytes) | |
1265 | { | |
1266 | int64_t len; | |
1267 | ||
1268 | if (bytes < 0) { | |
1269 | return -EIO; | |
1270 | } | |
1271 | ||
1272 | if (!blk_co_is_available(blk)) { | |
1273 | return -ENOMEDIUM; | |
1274 | } | |
1275 | ||
1276 | if (offset < 0) { | |
1277 | return -EIO; | |
1278 | } | |
1279 | ||
1280 | if (!blk->allow_write_beyond_eof) { | |
1281 | len = bdrv_co_getlength(blk_bs(blk)); | |
1282 | if (len < 0) { | |
1283 | return len; | |
1284 | } | |
1285 | ||
1286 | if (offset > len || len - offset < bytes) { | |
1287 | return -EIO; | |
1288 | } | |
1289 | } | |
1290 | ||
1291 | return 0; | |
1292 | } | |
1293 | ||
1294 | /* Are we currently in a drained section? */ | |
1295 | bool blk_in_drain(BlockBackend *blk) | |
1296 | { | |
1297 | GLOBAL_STATE_CODE(); /* change to IO_OR_GS_CODE(), if necessary */ | |
1298 | return qatomic_read(&blk->quiesce_counter); | |
1299 | } | |
1300 | ||
1301 | /* To be called between exactly one pair of blk_inc/dec_in_flight() */ | |
1302 | static void coroutine_fn blk_wait_while_drained(BlockBackend *blk) | |
1303 | { | |
1304 | assert(blk->in_flight > 0); | |
1305 | ||
1306 | if (qatomic_read(&blk->quiesce_counter) && | |
1307 | !qatomic_read(&blk->disable_request_queuing)) { | |
1308 | /* | |
1309 | * Take lock before decrementing in flight counter so main loop thread | |
1310 | * waits for us to enqueue ourselves before it can leave the drained | |
1311 | * section. | |
1312 | */ | |
1313 | qemu_mutex_lock(&blk->queued_requests_lock); | |
1314 | blk_dec_in_flight(blk); | |
1315 | qemu_co_queue_wait(&blk->queued_requests, &blk->queued_requests_lock); | |
1316 | blk_inc_in_flight(blk); | |
1317 | qemu_mutex_unlock(&blk->queued_requests_lock); | |
1318 | } | |
1319 | } | |
1320 | ||
1321 | /* To be called between exactly one pair of blk_inc/dec_in_flight() */ | |
1322 | static int coroutine_fn | |
1323 | blk_co_do_preadv_part(BlockBackend *blk, int64_t offset, int64_t bytes, | |
1324 | QEMUIOVector *qiov, size_t qiov_offset, | |
1325 | BdrvRequestFlags flags) | |
1326 | { | |
1327 | int ret; | |
1328 | BlockDriverState *bs; | |
1329 | IO_CODE(); | |
1330 | ||
1331 | blk_wait_while_drained(blk); | |
1332 | GRAPH_RDLOCK_GUARD(); | |
1333 | ||
1334 | /* Call blk_bs() only after waiting, the graph may have changed */ | |
1335 | bs = blk_bs(blk); | |
1336 | trace_blk_co_preadv(blk, bs, offset, bytes, flags); | |
1337 | ||
1338 | ret = blk_check_byte_request(blk, offset, bytes); | |
1339 | if (ret < 0) { | |
1340 | return ret; | |
1341 | } | |
1342 | ||
1343 | bdrv_inc_in_flight(bs); | |
1344 | ||
1345 | /* throttling disk I/O */ | |
1346 | if (blk->public.throttle_group_member.throttle_state) { | |
1347 | throttle_group_co_io_limits_intercept(&blk->public.throttle_group_member, | |
1348 | bytes, THROTTLE_READ); | |
1349 | } | |
1350 | ||
1351 | ret = bdrv_co_preadv_part(blk->root, offset, bytes, qiov, qiov_offset, | |
1352 | flags); | |
1353 | bdrv_dec_in_flight(bs); | |
1354 | return ret; | |
1355 | } | |
1356 | ||
1357 | int coroutine_fn blk_co_pread(BlockBackend *blk, int64_t offset, int64_t bytes, | |
1358 | void *buf, BdrvRequestFlags flags) | |
1359 | { | |
1360 | QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); | |
1361 | IO_OR_GS_CODE(); | |
1362 | ||
1363 | assert(bytes <= SIZE_MAX); | |
1364 | ||
1365 | return blk_co_preadv(blk, offset, bytes, &qiov, flags); | |
1366 | } | |
1367 | ||
1368 | int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset, | |
1369 | int64_t bytes, QEMUIOVector *qiov, | |
1370 | BdrvRequestFlags flags) | |
1371 | { | |
1372 | int ret; | |
1373 | IO_OR_GS_CODE(); | |
1374 | ||
1375 | blk_inc_in_flight(blk); | |
1376 | ret = blk_co_do_preadv_part(blk, offset, bytes, qiov, 0, flags); | |
1377 | blk_dec_in_flight(blk); | |
1378 | ||
1379 | return ret; | |
1380 | } | |
1381 | ||
1382 | int coroutine_fn blk_co_preadv_part(BlockBackend *blk, int64_t offset, | |
1383 | int64_t bytes, QEMUIOVector *qiov, | |
1384 | size_t qiov_offset, BdrvRequestFlags flags) | |
1385 | { | |
1386 | int ret; | |
1387 | IO_OR_GS_CODE(); | |
1388 | ||
1389 | blk_inc_in_flight(blk); | |
1390 | ret = blk_co_do_preadv_part(blk, offset, bytes, qiov, qiov_offset, flags); | |
1391 | blk_dec_in_flight(blk); | |
1392 | ||
1393 | return ret; | |
1394 | } | |
1395 | ||
1396 | /* To be called between exactly one pair of blk_inc/dec_in_flight() */ | |
1397 | static int coroutine_fn | |
1398 | blk_co_do_pwritev_part(BlockBackend *blk, int64_t offset, int64_t bytes, | |
1399 | QEMUIOVector *qiov, size_t qiov_offset, | |
1400 | BdrvRequestFlags flags) | |
1401 | { | |
1402 | int ret; | |
1403 | BlockDriverState *bs; | |
1404 | IO_CODE(); | |
1405 | ||
1406 | blk_wait_while_drained(blk); | |
1407 | GRAPH_RDLOCK_GUARD(); | |
1408 | ||
1409 | /* Call blk_bs() only after waiting, the graph may have changed */ | |
1410 | bs = blk_bs(blk); | |
1411 | trace_blk_co_pwritev(blk, bs, offset, bytes, flags); | |
1412 | ||
1413 | ret = blk_check_byte_request(blk, offset, bytes); | |
1414 | if (ret < 0) { | |
1415 | return ret; | |
1416 | } | |
1417 | ||
1418 | bdrv_inc_in_flight(bs); | |
1419 | /* throttling disk I/O */ | |
1420 | if (blk->public.throttle_group_member.throttle_state) { | |
1421 | throttle_group_co_io_limits_intercept(&blk->public.throttle_group_member, | |
1422 | bytes, THROTTLE_WRITE); | |
1423 | } | |
1424 | ||
1425 | if (!blk->enable_write_cache) { | |
1426 | flags |= BDRV_REQ_FUA; | |
1427 | } | |
1428 | ||
1429 | ret = bdrv_co_pwritev_part(blk->root, offset, bytes, qiov, qiov_offset, | |
1430 | flags); | |
1431 | bdrv_dec_in_flight(bs); | |
1432 | return ret; | |
1433 | } | |
1434 | ||
1435 | int coroutine_fn blk_co_pwritev_part(BlockBackend *blk, int64_t offset, | |
1436 | int64_t bytes, | |
1437 | QEMUIOVector *qiov, size_t qiov_offset, | |
1438 | BdrvRequestFlags flags) | |
1439 | { | |
1440 | int ret; | |
1441 | IO_OR_GS_CODE(); | |
1442 | ||
1443 | blk_inc_in_flight(blk); | |
1444 | ret = blk_co_do_pwritev_part(blk, offset, bytes, qiov, qiov_offset, flags); | |
1445 | blk_dec_in_flight(blk); | |
1446 | ||
1447 | return ret; | |
1448 | } | |
1449 | ||
1450 | int coroutine_fn blk_co_pwrite(BlockBackend *blk, int64_t offset, int64_t bytes, | |
1451 | const void *buf, BdrvRequestFlags flags) | |
1452 | { | |
1453 | QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); | |
1454 | IO_OR_GS_CODE(); | |
1455 | ||
1456 | assert(bytes <= SIZE_MAX); | |
1457 | ||
1458 | return blk_co_pwritev(blk, offset, bytes, &qiov, flags); | |
1459 | } | |
1460 | ||
1461 | int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset, | |
1462 | int64_t bytes, QEMUIOVector *qiov, | |
1463 | BdrvRequestFlags flags) | |
1464 | { | |
1465 | IO_OR_GS_CODE(); | |
1466 | return blk_co_pwritev_part(blk, offset, bytes, qiov, 0, flags); | |
1467 | } | |
1468 | ||
1469 | int coroutine_fn blk_co_block_status_above(BlockBackend *blk, | |
1470 | BlockDriverState *base, | |
1471 | int64_t offset, int64_t bytes, | |
1472 | int64_t *pnum, int64_t *map, | |
1473 | BlockDriverState **file) | |
1474 | { | |
1475 | IO_CODE(); | |
1476 | GRAPH_RDLOCK_GUARD(); | |
1477 | return bdrv_co_block_status_above(blk_bs(blk), base, offset, bytes, pnum, | |
1478 | map, file); | |
1479 | } | |
1480 | ||
1481 | int coroutine_fn blk_co_is_allocated_above(BlockBackend *blk, | |
1482 | BlockDriverState *base, | |
1483 | bool include_base, int64_t offset, | |
1484 | int64_t bytes, int64_t *pnum) | |
1485 | { | |
1486 | IO_CODE(); | |
1487 | GRAPH_RDLOCK_GUARD(); | |
1488 | return bdrv_co_is_allocated_above(blk_bs(blk), base, include_base, offset, | |
1489 | bytes, pnum); | |
1490 | } | |
1491 | ||
1492 | typedef struct BlkRwCo { | |
1493 | BlockBackend *blk; | |
1494 | int64_t offset; | |
1495 | void *iobuf; | |
1496 | int ret; | |
1497 | BdrvRequestFlags flags; | |
1498 | } BlkRwCo; | |
1499 | ||
1500 | int blk_make_zero(BlockBackend *blk, BdrvRequestFlags flags) | |
1501 | { | |
1502 | GLOBAL_STATE_CODE(); | |
1503 | return bdrv_make_zero(blk->root, flags); | |
1504 | } | |
1505 | ||
1506 | void blk_inc_in_flight(BlockBackend *blk) | |
1507 | { | |
1508 | IO_CODE(); | |
1509 | qatomic_inc(&blk->in_flight); | |
1510 | } | |
1511 | ||
1512 | void blk_dec_in_flight(BlockBackend *blk) | |
1513 | { | |
1514 | IO_CODE(); | |
1515 | qatomic_dec(&blk->in_flight); | |
1516 | aio_wait_kick(); | |
1517 | } | |
1518 | ||
1519 | static void error_callback_bh(void *opaque) | |
1520 | { | |
1521 | struct BlockBackendAIOCB *acb = opaque; | |
1522 | ||
1523 | blk_dec_in_flight(acb->blk); | |
1524 | acb->common.cb(acb->common.opaque, acb->ret); | |
1525 | qemu_aio_unref(acb); | |
1526 | } | |
1527 | ||
1528 | BlockAIOCB *blk_abort_aio_request(BlockBackend *blk, | |
1529 | BlockCompletionFunc *cb, | |
1530 | void *opaque, int ret) | |
1531 | { | |
1532 | struct BlockBackendAIOCB *acb; | |
1533 | IO_CODE(); | |
1534 | ||
1535 | blk_inc_in_flight(blk); | |
1536 | acb = blk_aio_get(&block_backend_aiocb_info, blk, cb, opaque); | |
1537 | acb->blk = blk; | |
1538 | acb->ret = ret; | |
1539 | ||
1540 | replay_bh_schedule_oneshot_event(qemu_get_current_aio_context(), | |
1541 | error_callback_bh, acb); | |
1542 | return &acb->common; | |
1543 | } | |
1544 | ||
1545 | typedef struct BlkAioEmAIOCB { | |
1546 | BlockAIOCB common; | |
1547 | BlkRwCo rwco; | |
1548 | int64_t bytes; | |
1549 | bool has_returned; | |
1550 | } BlkAioEmAIOCB; | |
1551 | ||
1552 | static const AIOCBInfo blk_aio_em_aiocb_info = { | |
1553 | .aiocb_size = sizeof(BlkAioEmAIOCB), | |
1554 | }; | |
1555 | ||
1556 | static void blk_aio_complete(BlkAioEmAIOCB *acb) | |
1557 | { | |
1558 | if (acb->has_returned) { | |
1559 | acb->common.cb(acb->common.opaque, acb->rwco.ret); | |
1560 | blk_dec_in_flight(acb->rwco.blk); | |
1561 | qemu_aio_unref(acb); | |
1562 | } | |
1563 | } | |
1564 | ||
1565 | static void blk_aio_complete_bh(void *opaque) | |
1566 | { | |
1567 | BlkAioEmAIOCB *acb = opaque; | |
1568 | assert(acb->has_returned); | |
1569 | blk_aio_complete(acb); | |
1570 | } | |
1571 | ||
1572 | static BlockAIOCB *blk_aio_prwv(BlockBackend *blk, int64_t offset, | |
1573 | int64_t bytes, | |
1574 | void *iobuf, CoroutineEntry co_entry, | |
1575 | BdrvRequestFlags flags, | |
1576 | BlockCompletionFunc *cb, void *opaque) | |
1577 | { | |
1578 | BlkAioEmAIOCB *acb; | |
1579 | Coroutine *co; | |
1580 | ||
1581 | blk_inc_in_flight(blk); | |
1582 | acb = blk_aio_get(&blk_aio_em_aiocb_info, blk, cb, opaque); | |
1583 | acb->rwco = (BlkRwCo) { | |
1584 | .blk = blk, | |
1585 | .offset = offset, | |
1586 | .iobuf = iobuf, | |
1587 | .flags = flags, | |
1588 | .ret = NOT_DONE, | |
1589 | }; | |
1590 | acb->bytes = bytes; | |
1591 | acb->has_returned = false; | |
1592 | ||
1593 | co = qemu_coroutine_create(co_entry, acb); | |
1594 | aio_co_enter(qemu_get_current_aio_context(), co); | |
1595 | ||
1596 | acb->has_returned = true; | |
1597 | if (acb->rwco.ret != NOT_DONE) { | |
1598 | replay_bh_schedule_oneshot_event(qemu_get_current_aio_context(), | |
1599 | blk_aio_complete_bh, acb); | |
1600 | } | |
1601 | ||
1602 | return &acb->common; | |
1603 | } | |
1604 | ||
1605 | static void coroutine_fn blk_aio_read_entry(void *opaque) | |
1606 | { | |
1607 | BlkAioEmAIOCB *acb = opaque; | |
1608 | BlkRwCo *rwco = &acb->rwco; | |
1609 | QEMUIOVector *qiov = rwco->iobuf; | |
1610 | ||
1611 | assert(qiov->size == acb->bytes); | |
1612 | rwco->ret = blk_co_do_preadv_part(rwco->blk, rwco->offset, acb->bytes, qiov, | |
1613 | 0, rwco->flags); | |
1614 | blk_aio_complete(acb); | |
1615 | } | |
1616 | ||
1617 | static void coroutine_fn blk_aio_write_entry(void *opaque) | |
1618 | { | |
1619 | BlkAioEmAIOCB *acb = opaque; | |
1620 | BlkRwCo *rwco = &acb->rwco; | |
1621 | QEMUIOVector *qiov = rwco->iobuf; | |
1622 | ||
1623 | assert(!qiov || qiov->size == acb->bytes); | |
1624 | rwco->ret = blk_co_do_pwritev_part(rwco->blk, rwco->offset, acb->bytes, | |
1625 | qiov, 0, rwco->flags); | |
1626 | blk_aio_complete(acb); | |
1627 | } | |
1628 | ||
1629 | BlockAIOCB *blk_aio_pwrite_zeroes(BlockBackend *blk, int64_t offset, | |
1630 | int64_t bytes, BdrvRequestFlags flags, | |
1631 | BlockCompletionFunc *cb, void *opaque) | |
1632 | { | |
1633 | IO_CODE(); | |
1634 | return blk_aio_prwv(blk, offset, bytes, NULL, blk_aio_write_entry, | |
1635 | flags | BDRV_REQ_ZERO_WRITE, cb, opaque); | |
1636 | } | |
1637 | ||
1638 | int64_t coroutine_fn blk_co_getlength(BlockBackend *blk) | |
1639 | { | |
1640 | IO_CODE(); | |
1641 | GRAPH_RDLOCK_GUARD(); | |
1642 | ||
1643 | if (!blk_co_is_available(blk)) { | |
1644 | return -ENOMEDIUM; | |
1645 | } | |
1646 | ||
1647 | return bdrv_co_getlength(blk_bs(blk)); | |
1648 | } | |
1649 | ||
1650 | int64_t coroutine_fn blk_co_nb_sectors(BlockBackend *blk) | |
1651 | { | |
1652 | BlockDriverState *bs = blk_bs(blk); | |
1653 | ||
1654 | IO_CODE(); | |
1655 | GRAPH_RDLOCK_GUARD(); | |
1656 | ||
1657 | if (!bs) { | |
1658 | return -ENOMEDIUM; | |
1659 | } else { | |
1660 | return bdrv_co_nb_sectors(bs); | |
1661 | } | |
1662 | } | |
1663 | ||
1664 | /* | |
1665 | * This wrapper is written by hand because this function is in the hot I/O path, | |
1666 | * via blk_get_geometry. | |
1667 | */ | |
1668 | int64_t coroutine_mixed_fn blk_nb_sectors(BlockBackend *blk) | |
1669 | { | |
1670 | BlockDriverState *bs = blk_bs(blk); | |
1671 | ||
1672 | IO_CODE(); | |
1673 | ||
1674 | if (!bs) { | |
1675 | return -ENOMEDIUM; | |
1676 | } else { | |
1677 | return bdrv_nb_sectors(bs); | |
1678 | } | |
1679 | } | |
1680 | ||
1681 | /* return 0 as number of sectors if no device present or error */ | |
1682 | void coroutine_fn blk_co_get_geometry(BlockBackend *blk, | |
1683 | uint64_t *nb_sectors_ptr) | |
1684 | { | |
1685 | int64_t ret = blk_co_nb_sectors(blk); | |
1686 | *nb_sectors_ptr = ret < 0 ? 0 : ret; | |
1687 | } | |
1688 | ||
1689 | /* | |
1690 | * This wrapper is written by hand because this function is in the hot I/O path. | |
1691 | */ | |
1692 | void coroutine_mixed_fn blk_get_geometry(BlockBackend *blk, | |
1693 | uint64_t *nb_sectors_ptr) | |
1694 | { | |
1695 | int64_t ret = blk_nb_sectors(blk); | |
1696 | *nb_sectors_ptr = ret < 0 ? 0 : ret; | |
1697 | } | |
1698 | ||
1699 | BlockAIOCB *blk_aio_preadv(BlockBackend *blk, int64_t offset, | |
1700 | QEMUIOVector *qiov, BdrvRequestFlags flags, | |
1701 | BlockCompletionFunc *cb, void *opaque) | |
1702 | { | |
1703 | IO_CODE(); | |
1704 | assert((uint64_t)qiov->size <= INT64_MAX); | |
1705 | return blk_aio_prwv(blk, offset, qiov->size, qiov, | |
1706 | blk_aio_read_entry, flags, cb, opaque); | |
1707 | } | |
1708 | ||
1709 | BlockAIOCB *blk_aio_pwritev(BlockBackend *blk, int64_t offset, | |
1710 | QEMUIOVector *qiov, BdrvRequestFlags flags, | |
1711 | BlockCompletionFunc *cb, void *opaque) | |
1712 | { | |
1713 | IO_CODE(); | |
1714 | assert((uint64_t)qiov->size <= INT64_MAX); | |
1715 | return blk_aio_prwv(blk, offset, qiov->size, qiov, | |
1716 | blk_aio_write_entry, flags, cb, opaque); | |
1717 | } | |
1718 | ||
1719 | void blk_aio_cancel(BlockAIOCB *acb) | |
1720 | { | |
1721 | GLOBAL_STATE_CODE(); | |
1722 | bdrv_aio_cancel(acb); | |
1723 | } | |
1724 | ||
1725 | void blk_aio_cancel_async(BlockAIOCB *acb) | |
1726 | { | |
1727 | IO_CODE(); | |
1728 | bdrv_aio_cancel_async(acb); | |
1729 | } | |
1730 | ||
1731 | /* To be called between exactly one pair of blk_inc/dec_in_flight() */ | |
1732 | static int coroutine_fn | |
1733 | blk_co_do_ioctl(BlockBackend *blk, unsigned long int req, void *buf) | |
1734 | { | |
1735 | IO_CODE(); | |
1736 | ||
1737 | blk_wait_while_drained(blk); | |
1738 | GRAPH_RDLOCK_GUARD(); | |
1739 | ||
1740 | if (!blk_co_is_available(blk)) { | |
1741 | return -ENOMEDIUM; | |
1742 | } | |
1743 | ||
1744 | return bdrv_co_ioctl(blk_bs(blk), req, buf); | |
1745 | } | |
1746 | ||
1747 | int coroutine_fn blk_co_ioctl(BlockBackend *blk, unsigned long int req, | |
1748 | void *buf) | |
1749 | { | |
1750 | int ret; | |
1751 | IO_OR_GS_CODE(); | |
1752 | ||
1753 | blk_inc_in_flight(blk); | |
1754 | ret = blk_co_do_ioctl(blk, req, buf); | |
1755 | blk_dec_in_flight(blk); | |
1756 | ||
1757 | return ret; | |
1758 | } | |
1759 | ||
1760 | static void coroutine_fn blk_aio_ioctl_entry(void *opaque) | |
1761 | { | |
1762 | BlkAioEmAIOCB *acb = opaque; | |
1763 | BlkRwCo *rwco = &acb->rwco; | |
1764 | ||
1765 | rwco->ret = blk_co_do_ioctl(rwco->blk, rwco->offset, rwco->iobuf); | |
1766 | ||
1767 | blk_aio_complete(acb); | |
1768 | } | |
1769 | ||
1770 | BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf, | |
1771 | BlockCompletionFunc *cb, void *opaque) | |
1772 | { | |
1773 | IO_CODE(); | |
1774 | return blk_aio_prwv(blk, req, 0, buf, blk_aio_ioctl_entry, 0, cb, opaque); | |
1775 | } | |
1776 | ||
1777 | /* To be called between exactly one pair of blk_inc/dec_in_flight() */ | |
1778 | static int coroutine_fn | |
1779 | blk_co_do_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes) | |
1780 | { | |
1781 | int ret; | |
1782 | IO_CODE(); | |
1783 | ||
1784 | blk_wait_while_drained(blk); | |
1785 | GRAPH_RDLOCK_GUARD(); | |
1786 | ||
1787 | ret = blk_check_byte_request(blk, offset, bytes); | |
1788 | if (ret < 0) { | |
1789 | return ret; | |
1790 | } | |
1791 | ||
1792 | return bdrv_co_pdiscard(blk->root, offset, bytes); | |
1793 | } | |
1794 | ||
1795 | static void coroutine_fn blk_aio_pdiscard_entry(void *opaque) | |
1796 | { | |
1797 | BlkAioEmAIOCB *acb = opaque; | |
1798 | BlkRwCo *rwco = &acb->rwco; | |
1799 | ||
1800 | rwco->ret = blk_co_do_pdiscard(rwco->blk, rwco->offset, acb->bytes); | |
1801 | blk_aio_complete(acb); | |
1802 | } | |
1803 | ||
1804 | BlockAIOCB *blk_aio_pdiscard(BlockBackend *blk, | |
1805 | int64_t offset, int64_t bytes, | |
1806 | BlockCompletionFunc *cb, void *opaque) | |
1807 | { | |
1808 | IO_CODE(); | |
1809 | return blk_aio_prwv(blk, offset, bytes, NULL, blk_aio_pdiscard_entry, 0, | |
1810 | cb, opaque); | |
1811 | } | |
1812 | ||
1813 | int coroutine_fn blk_co_pdiscard(BlockBackend *blk, int64_t offset, | |
1814 | int64_t bytes) | |
1815 | { | |
1816 | int ret; | |
1817 | IO_OR_GS_CODE(); | |
1818 | ||
1819 | blk_inc_in_flight(blk); | |
1820 | ret = blk_co_do_pdiscard(blk, offset, bytes); | |
1821 | blk_dec_in_flight(blk); | |
1822 | ||
1823 | return ret; | |
1824 | } | |
1825 | ||
1826 | /* To be called between exactly one pair of blk_inc/dec_in_flight() */ | |
1827 | static int coroutine_fn blk_co_do_flush(BlockBackend *blk) | |
1828 | { | |
1829 | IO_CODE(); | |
1830 | blk_wait_while_drained(blk); | |
1831 | GRAPH_RDLOCK_GUARD(); | |
1832 | ||
1833 | if (!blk_co_is_available(blk)) { | |
1834 | return -ENOMEDIUM; | |
1835 | } | |
1836 | ||
1837 | return bdrv_co_flush(blk_bs(blk)); | |
1838 | } | |
1839 | ||
1840 | static void coroutine_fn blk_aio_flush_entry(void *opaque) | |
1841 | { | |
1842 | BlkAioEmAIOCB *acb = opaque; | |
1843 | BlkRwCo *rwco = &acb->rwco; | |
1844 | ||
1845 | rwco->ret = blk_co_do_flush(rwco->blk); | |
1846 | blk_aio_complete(acb); | |
1847 | } | |
1848 | ||
1849 | BlockAIOCB *blk_aio_flush(BlockBackend *blk, | |
1850 | BlockCompletionFunc *cb, void *opaque) | |
1851 | { | |
1852 | IO_CODE(); | |
1853 | return blk_aio_prwv(blk, 0, 0, NULL, blk_aio_flush_entry, 0, cb, opaque); | |
1854 | } | |
1855 | ||
1856 | int coroutine_fn blk_co_flush(BlockBackend *blk) | |
1857 | { | |
1858 | int ret; | |
1859 | IO_OR_GS_CODE(); | |
1860 | ||
1861 | blk_inc_in_flight(blk); | |
1862 | ret = blk_co_do_flush(blk); | |
1863 | blk_dec_in_flight(blk); | |
1864 | ||
1865 | return ret; | |
1866 | } | |
1867 | ||
1868 | static void coroutine_fn blk_aio_zone_report_entry(void *opaque) | |
1869 | { | |
1870 | BlkAioEmAIOCB *acb = opaque; | |
1871 | BlkRwCo *rwco = &acb->rwco; | |
1872 | ||
1873 | rwco->ret = blk_co_zone_report(rwco->blk, rwco->offset, | |
1874 | (unsigned int*)(uintptr_t)acb->bytes, | |
1875 | rwco->iobuf); | |
1876 | blk_aio_complete(acb); | |
1877 | } | |
1878 | ||
1879 | BlockAIOCB *blk_aio_zone_report(BlockBackend *blk, int64_t offset, | |
1880 | unsigned int *nr_zones, | |
1881 | BlockZoneDescriptor *zones, | |
1882 | BlockCompletionFunc *cb, void *opaque) | |
1883 | { | |
1884 | BlkAioEmAIOCB *acb; | |
1885 | Coroutine *co; | |
1886 | IO_CODE(); | |
1887 | ||
1888 | blk_inc_in_flight(blk); | |
1889 | acb = blk_aio_get(&blk_aio_em_aiocb_info, blk, cb, opaque); | |
1890 | acb->rwco = (BlkRwCo) { | |
1891 | .blk = blk, | |
1892 | .offset = offset, | |
1893 | .iobuf = zones, | |
1894 | .ret = NOT_DONE, | |
1895 | }; | |
1896 | acb->bytes = (int64_t)(uintptr_t)nr_zones, | |
1897 | acb->has_returned = false; | |
1898 | ||
1899 | co = qemu_coroutine_create(blk_aio_zone_report_entry, acb); | |
1900 | aio_co_enter(qemu_get_current_aio_context(), co); | |
1901 | ||
1902 | acb->has_returned = true; | |
1903 | if (acb->rwco.ret != NOT_DONE) { | |
1904 | replay_bh_schedule_oneshot_event(qemu_get_current_aio_context(), | |
1905 | blk_aio_complete_bh, acb); | |
1906 | } | |
1907 | ||
1908 | return &acb->common; | |
1909 | } | |
1910 | ||
1911 | static void coroutine_fn blk_aio_zone_mgmt_entry(void *opaque) | |
1912 | { | |
1913 | BlkAioEmAIOCB *acb = opaque; | |
1914 | BlkRwCo *rwco = &acb->rwco; | |
1915 | ||
1916 | rwco->ret = blk_co_zone_mgmt(rwco->blk, | |
1917 | (BlockZoneOp)(uintptr_t)rwco->iobuf, | |
1918 | rwco->offset, acb->bytes); | |
1919 | blk_aio_complete(acb); | |
1920 | } | |
1921 | ||
1922 | BlockAIOCB *blk_aio_zone_mgmt(BlockBackend *blk, BlockZoneOp op, | |
1923 | int64_t offset, int64_t len, | |
1924 | BlockCompletionFunc *cb, void *opaque) { | |
1925 | BlkAioEmAIOCB *acb; | |
1926 | Coroutine *co; | |
1927 | IO_CODE(); | |
1928 | ||
1929 | blk_inc_in_flight(blk); | |
1930 | acb = blk_aio_get(&blk_aio_em_aiocb_info, blk, cb, opaque); | |
1931 | acb->rwco = (BlkRwCo) { | |
1932 | .blk = blk, | |
1933 | .offset = offset, | |
1934 | .iobuf = (void *)(uintptr_t)op, | |
1935 | .ret = NOT_DONE, | |
1936 | }; | |
1937 | acb->bytes = len; | |
1938 | acb->has_returned = false; | |
1939 | ||
1940 | co = qemu_coroutine_create(blk_aio_zone_mgmt_entry, acb); | |
1941 | aio_co_enter(qemu_get_current_aio_context(), co); | |
1942 | ||
1943 | acb->has_returned = true; | |
1944 | if (acb->rwco.ret != NOT_DONE) { | |
1945 | replay_bh_schedule_oneshot_event(qemu_get_current_aio_context(), | |
1946 | blk_aio_complete_bh, acb); | |
1947 | } | |
1948 | ||
1949 | return &acb->common; | |
1950 | } | |
1951 | ||
1952 | static void coroutine_fn blk_aio_zone_append_entry(void *opaque) | |
1953 | { | |
1954 | BlkAioEmAIOCB *acb = opaque; | |
1955 | BlkRwCo *rwco = &acb->rwco; | |
1956 | ||
1957 | rwco->ret = blk_co_zone_append(rwco->blk, (int64_t *)(uintptr_t)acb->bytes, | |
1958 | rwco->iobuf, rwco->flags); | |
1959 | blk_aio_complete(acb); | |
1960 | } | |
1961 | ||
1962 | BlockAIOCB *blk_aio_zone_append(BlockBackend *blk, int64_t *offset, | |
1963 | QEMUIOVector *qiov, BdrvRequestFlags flags, | |
1964 | BlockCompletionFunc *cb, void *opaque) { | |
1965 | BlkAioEmAIOCB *acb; | |
1966 | Coroutine *co; | |
1967 | IO_CODE(); | |
1968 | ||
1969 | blk_inc_in_flight(blk); | |
1970 | acb = blk_aio_get(&blk_aio_em_aiocb_info, blk, cb, opaque); | |
1971 | acb->rwco = (BlkRwCo) { | |
1972 | .blk = blk, | |
1973 | .ret = NOT_DONE, | |
1974 | .flags = flags, | |
1975 | .iobuf = qiov, | |
1976 | }; | |
1977 | acb->bytes = (int64_t)(uintptr_t)offset; | |
1978 | acb->has_returned = false; | |
1979 | ||
1980 | co = qemu_coroutine_create(blk_aio_zone_append_entry, acb); | |
1981 | aio_co_enter(qemu_get_current_aio_context(), co); | |
1982 | acb->has_returned = true; | |
1983 | if (acb->rwco.ret != NOT_DONE) { | |
1984 | replay_bh_schedule_oneshot_event(qemu_get_current_aio_context(), | |
1985 | blk_aio_complete_bh, acb); | |
1986 | } | |
1987 | ||
1988 | return &acb->common; | |
1989 | } | |
1990 | ||
1991 | /* | |
1992 | * Send a zone_report command. | |
1993 | * offset is a byte offset from the start of the device. No alignment | |
1994 | * required for offset. | |
1995 | * nr_zones represents IN maximum and OUT actual. | |
1996 | */ | |
1997 | int coroutine_fn blk_co_zone_report(BlockBackend *blk, int64_t offset, | |
1998 | unsigned int *nr_zones, | |
1999 | BlockZoneDescriptor *zones) | |
2000 | { | |
2001 | int ret; | |
2002 | IO_CODE(); | |
2003 | ||
2004 | blk_inc_in_flight(blk); /* increase before waiting */ | |
2005 | blk_wait_while_drained(blk); | |
2006 | GRAPH_RDLOCK_GUARD(); | |
2007 | if (!blk_is_available(blk)) { | |
2008 | blk_dec_in_flight(blk); | |
2009 | return -ENOMEDIUM; | |
2010 | } | |
2011 | ret = bdrv_co_zone_report(blk_bs(blk), offset, nr_zones, zones); | |
2012 | blk_dec_in_flight(blk); | |
2013 | return ret; | |
2014 | } | |
2015 | ||
2016 | /* | |
2017 | * Send a zone_management command. | |
2018 | * op is the zone operation; | |
2019 | * offset is the byte offset from the start of the zoned device; | |
2020 | * len is the maximum number of bytes the command should operate on. It | |
2021 | * should be aligned with the device zone size. | |
2022 | */ | |
2023 | int coroutine_fn blk_co_zone_mgmt(BlockBackend *blk, BlockZoneOp op, | |
2024 | int64_t offset, int64_t len) | |
2025 | { | |
2026 | int ret; | |
2027 | IO_CODE(); | |
2028 | ||
2029 | blk_inc_in_flight(blk); | |
2030 | blk_wait_while_drained(blk); | |
2031 | GRAPH_RDLOCK_GUARD(); | |
2032 | ||
2033 | ret = blk_check_byte_request(blk, offset, len); | |
2034 | if (ret < 0) { | |
2035 | blk_dec_in_flight(blk); | |
2036 | return ret; | |
2037 | } | |
2038 | ||
2039 | ret = bdrv_co_zone_mgmt(blk_bs(blk), op, offset, len); | |
2040 | blk_dec_in_flight(blk); | |
2041 | return ret; | |
2042 | } | |
2043 | ||
2044 | /* | |
2045 | * Send a zone_append command. | |
2046 | */ | |
2047 | int coroutine_fn blk_co_zone_append(BlockBackend *blk, int64_t *offset, | |
2048 | QEMUIOVector *qiov, BdrvRequestFlags flags) | |
2049 | { | |
2050 | int ret; | |
2051 | IO_CODE(); | |
2052 | ||
2053 | blk_inc_in_flight(blk); | |
2054 | blk_wait_while_drained(blk); | |
2055 | GRAPH_RDLOCK_GUARD(); | |
2056 | if (!blk_is_available(blk)) { | |
2057 | blk_dec_in_flight(blk); | |
2058 | return -ENOMEDIUM; | |
2059 | } | |
2060 | ||
2061 | ret = bdrv_co_zone_append(blk_bs(blk), offset, qiov, flags); | |
2062 | blk_dec_in_flight(blk); | |
2063 | return ret; | |
2064 | } | |
2065 | ||
2066 | void blk_drain(BlockBackend *blk) | |
2067 | { | |
2068 | BlockDriverState *bs = blk_bs(blk); | |
2069 | GLOBAL_STATE_CODE(); | |
2070 | ||
2071 | if (bs) { | |
2072 | bdrv_ref(bs); | |
2073 | bdrv_drained_begin(bs); | |
2074 | } | |
2075 | ||
2076 | /* We may have -ENOMEDIUM completions in flight */ | |
2077 | AIO_WAIT_WHILE(blk_get_aio_context(blk), | |
2078 | qatomic_read(&blk->in_flight) > 0); | |
2079 | ||
2080 | if (bs) { | |
2081 | bdrv_drained_end(bs); | |
2082 | bdrv_unref(bs); | |
2083 | } | |
2084 | } | |
2085 | ||
2086 | void blk_drain_all(void) | |
2087 | { | |
2088 | BlockBackend *blk = NULL; | |
2089 | ||
2090 | GLOBAL_STATE_CODE(); | |
2091 | ||
2092 | bdrv_drain_all_begin(); | |
2093 | ||
2094 | while ((blk = blk_all_next(blk)) != NULL) { | |
2095 | /* We may have -ENOMEDIUM completions in flight */ | |
2096 | AIO_WAIT_WHILE_UNLOCKED(NULL, qatomic_read(&blk->in_flight) > 0); | |
2097 | } | |
2098 | ||
2099 | bdrv_drain_all_end(); | |
2100 | } | |
2101 | ||
2102 | void blk_set_on_error(BlockBackend *blk, BlockdevOnError on_read_error, | |
2103 | BlockdevOnError on_write_error) | |
2104 | { | |
2105 | GLOBAL_STATE_CODE(); | |
2106 | blk->on_read_error = on_read_error; | |
2107 | blk->on_write_error = on_write_error; | |
2108 | } | |
2109 | ||
2110 | BlockdevOnError blk_get_on_error(BlockBackend *blk, bool is_read) | |
2111 | { | |
2112 | IO_CODE(); | |
2113 | return is_read ? blk->on_read_error : blk->on_write_error; | |
2114 | } | |
2115 | ||
2116 | BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read, | |
2117 | int error) | |
2118 | { | |
2119 | BlockdevOnError on_err = blk_get_on_error(blk, is_read); | |
2120 | IO_CODE(); | |
2121 | ||
2122 | switch (on_err) { | |
2123 | case BLOCKDEV_ON_ERROR_ENOSPC: | |
2124 | return (error == ENOSPC) ? | |
2125 | BLOCK_ERROR_ACTION_STOP : BLOCK_ERROR_ACTION_REPORT; | |
2126 | case BLOCKDEV_ON_ERROR_STOP: | |
2127 | return BLOCK_ERROR_ACTION_STOP; | |
2128 | case BLOCKDEV_ON_ERROR_REPORT: | |
2129 | return BLOCK_ERROR_ACTION_REPORT; | |
2130 | case BLOCKDEV_ON_ERROR_IGNORE: | |
2131 | return BLOCK_ERROR_ACTION_IGNORE; | |
2132 | case BLOCKDEV_ON_ERROR_AUTO: | |
2133 | default: | |
2134 | abort(); | |
2135 | } | |
2136 | } | |
2137 | ||
2138 | static void send_qmp_error_event(BlockBackend *blk, | |
2139 | BlockErrorAction action, | |
2140 | bool is_read, int error) | |
2141 | { | |
2142 | IoOperationType optype; | |
2143 | BlockDriverState *bs = blk_bs(blk); | |
2144 | ||
2145 | optype = is_read ? IO_OPERATION_TYPE_READ : IO_OPERATION_TYPE_WRITE; | |
2146 | qapi_event_send_block_io_error(blk_name(blk), | |
2147 | bs ? bdrv_get_node_name(bs) : NULL, optype, | |
2148 | action, blk_iostatus_is_enabled(blk), | |
2149 | error == ENOSPC, strerror(error)); | |
2150 | } | |
2151 | ||
2152 | /* This is done by device models because, while the block layer knows | |
2153 | * about the error, it does not know whether an operation comes from | |
2154 | * the device or the block layer (from a job, for example). | |
2155 | */ | |
2156 | void blk_error_action(BlockBackend *blk, BlockErrorAction action, | |
2157 | bool is_read, int error) | |
2158 | { | |
2159 | assert(error >= 0); | |
2160 | IO_CODE(); | |
2161 | ||
2162 | if (action == BLOCK_ERROR_ACTION_STOP) { | |
2163 | /* First set the iostatus, so that "info block" returns an iostatus | |
2164 | * that matches the events raised so far (an additional error iostatus | |
2165 | * is fine, but not a lost one). | |
2166 | */ | |
2167 | blk_iostatus_set_err(blk, error); | |
2168 | ||
2169 | /* Then raise the request to stop the VM and the event. | |
2170 | * qemu_system_vmstop_request_prepare has two effects. First, | |
2171 | * it ensures that the STOP event always comes after the | |
2172 | * BLOCK_IO_ERROR event. Second, it ensures that even if management | |
2173 | * can observe the STOP event and do a "cont" before the STOP | |
2174 | * event is issued, the VM will not stop. In this case, vm_start() | |
2175 | * also ensures that the STOP/RESUME pair of events is emitted. | |
2176 | */ | |
2177 | qemu_system_vmstop_request_prepare(); | |
2178 | send_qmp_error_event(blk, action, is_read, error); | |
2179 | qemu_system_vmstop_request(RUN_STATE_IO_ERROR); | |
2180 | } else { | |
2181 | send_qmp_error_event(blk, action, is_read, error); | |
2182 | } | |
2183 | } | |
2184 | ||
2185 | /* | |
2186 | * Returns true if the BlockBackend can support taking write permissions | |
2187 | * (because its root node is not read-only). | |
2188 | */ | |
2189 | bool blk_supports_write_perm(BlockBackend *blk) | |
2190 | { | |
2191 | BlockDriverState *bs = blk_bs(blk); | |
2192 | GLOBAL_STATE_CODE(); | |
2193 | ||
2194 | if (bs) { | |
2195 | return !bdrv_is_read_only(bs); | |
2196 | } else { | |
2197 | return blk->root_state.open_flags & BDRV_O_RDWR; | |
2198 | } | |
2199 | } | |
2200 | ||
2201 | /* | |
2202 | * Returns true if the BlockBackend can be written to in its current | |
2203 | * configuration (i.e. if write permission have been requested) | |
2204 | */ | |
2205 | bool blk_is_writable(BlockBackend *blk) | |
2206 | { | |
2207 | IO_CODE(); | |
2208 | return blk->perm & BLK_PERM_WRITE; | |
2209 | } | |
2210 | ||
2211 | bool blk_is_sg(BlockBackend *blk) | |
2212 | { | |
2213 | BlockDriverState *bs = blk_bs(blk); | |
2214 | GLOBAL_STATE_CODE(); | |
2215 | ||
2216 | if (!bs) { | |
2217 | return false; | |
2218 | } | |
2219 | ||
2220 | return bdrv_is_sg(bs); | |
2221 | } | |
2222 | ||
2223 | bool blk_enable_write_cache(BlockBackend *blk) | |
2224 | { | |
2225 | IO_CODE(); | |
2226 | return blk->enable_write_cache; | |
2227 | } | |
2228 | ||
2229 | void blk_set_enable_write_cache(BlockBackend *blk, bool wce) | |
2230 | { | |
2231 | IO_CODE(); | |
2232 | blk->enable_write_cache = wce; | |
2233 | } | |
2234 | ||
2235 | void blk_activate(BlockBackend *blk, Error **errp) | |
2236 | { | |
2237 | BlockDriverState *bs = blk_bs(blk); | |
2238 | GLOBAL_STATE_CODE(); | |
2239 | ||
2240 | if (!bs) { | |
2241 | error_setg(errp, "Device '%s' has no medium", blk->name); | |
2242 | return; | |
2243 | } | |
2244 | ||
2245 | /* | |
2246 | * Migration code can call this function in coroutine context, so leave | |
2247 | * coroutine context if necessary. | |
2248 | */ | |
2249 | if (qemu_in_coroutine()) { | |
2250 | bdrv_co_activate(bs, errp); | |
2251 | } else { | |
2252 | GRAPH_RDLOCK_GUARD_MAINLOOP(); | |
2253 | bdrv_activate(bs, errp); | |
2254 | } | |
2255 | } | |
2256 | ||
2257 | bool coroutine_fn blk_co_is_inserted(BlockBackend *blk) | |
2258 | { | |
2259 | BlockDriverState *bs = blk_bs(blk); | |
2260 | IO_CODE(); | |
2261 | assert_bdrv_graph_readable(); | |
2262 | ||
2263 | return bs && bdrv_co_is_inserted(bs); | |
2264 | } | |
2265 | ||
2266 | bool coroutine_fn blk_co_is_available(BlockBackend *blk) | |
2267 | { | |
2268 | IO_CODE(); | |
2269 | return blk_co_is_inserted(blk) && !blk_dev_is_tray_open(blk); | |
2270 | } | |
2271 | ||
2272 | void coroutine_fn blk_co_lock_medium(BlockBackend *blk, bool locked) | |
2273 | { | |
2274 | BlockDriverState *bs = blk_bs(blk); | |
2275 | IO_CODE(); | |
2276 | GRAPH_RDLOCK_GUARD(); | |
2277 | ||
2278 | if (bs) { | |
2279 | bdrv_co_lock_medium(bs, locked); | |
2280 | } | |
2281 | } | |
2282 | ||
2283 | void coroutine_fn blk_co_eject(BlockBackend *blk, bool eject_flag) | |
2284 | { | |
2285 | BlockDriverState *bs = blk_bs(blk); | |
2286 | char *id; | |
2287 | IO_CODE(); | |
2288 | GRAPH_RDLOCK_GUARD(); | |
2289 | ||
2290 | if (bs) { | |
2291 | bdrv_co_eject(bs, eject_flag); | |
2292 | } | |
2293 | ||
2294 | /* Whether or not we ejected on the backend, | |
2295 | * the frontend experienced a tray event. */ | |
2296 | id = blk_get_attached_dev_id(blk); | |
2297 | qapi_event_send_device_tray_moved(blk_name(blk), id, | |
2298 | eject_flag); | |
2299 | g_free(id); | |
2300 | } | |
2301 | ||
2302 | int blk_get_flags(BlockBackend *blk) | |
2303 | { | |
2304 | BlockDriverState *bs = blk_bs(blk); | |
2305 | GLOBAL_STATE_CODE(); | |
2306 | ||
2307 | if (bs) { | |
2308 | return bdrv_get_flags(bs); | |
2309 | } else { | |
2310 | return blk->root_state.open_flags; | |
2311 | } | |
2312 | } | |
2313 | ||
2314 | /* Returns the minimum request alignment, in bytes; guaranteed nonzero */ | |
2315 | uint32_t blk_get_request_alignment(BlockBackend *blk) | |
2316 | { | |
2317 | BlockDriverState *bs = blk_bs(blk); | |
2318 | IO_CODE(); | |
2319 | return bs ? bs->bl.request_alignment : BDRV_SECTOR_SIZE; | |
2320 | } | |
2321 | ||
2322 | /* Returns the maximum hardware transfer length, in bytes; guaranteed nonzero */ | |
2323 | uint64_t blk_get_max_hw_transfer(BlockBackend *blk) | |
2324 | { | |
2325 | BlockDriverState *bs = blk_bs(blk); | |
2326 | uint64_t max = INT_MAX; | |
2327 | IO_CODE(); | |
2328 | ||
2329 | if (bs) { | |
2330 | max = MIN_NON_ZERO(max, bs->bl.max_hw_transfer); | |
2331 | max = MIN_NON_ZERO(max, bs->bl.max_transfer); | |
2332 | } | |
2333 | return ROUND_DOWN(max, blk_get_request_alignment(blk)); | |
2334 | } | |
2335 | ||
2336 | /* Returns the maximum transfer length, in bytes; guaranteed nonzero */ | |
2337 | uint32_t blk_get_max_transfer(BlockBackend *blk) | |
2338 | { | |
2339 | BlockDriverState *bs = blk_bs(blk); | |
2340 | uint32_t max = INT_MAX; | |
2341 | IO_CODE(); | |
2342 | ||
2343 | if (bs) { | |
2344 | max = MIN_NON_ZERO(max, bs->bl.max_transfer); | |
2345 | } | |
2346 | return ROUND_DOWN(max, blk_get_request_alignment(blk)); | |
2347 | } | |
2348 | ||
2349 | int blk_get_max_hw_iov(BlockBackend *blk) | |
2350 | { | |
2351 | IO_CODE(); | |
2352 | return MIN_NON_ZERO(blk->root->bs->bl.max_hw_iov, | |
2353 | blk->root->bs->bl.max_iov); | |
2354 | } | |
2355 | ||
2356 | int blk_get_max_iov(BlockBackend *blk) | |
2357 | { | |
2358 | IO_CODE(); | |
2359 | return blk->root->bs->bl.max_iov; | |
2360 | } | |
2361 | ||
2362 | void *blk_try_blockalign(BlockBackend *blk, size_t size) | |
2363 | { | |
2364 | IO_CODE(); | |
2365 | return qemu_try_blockalign(blk ? blk_bs(blk) : NULL, size); | |
2366 | } | |
2367 | ||
2368 | void *blk_blockalign(BlockBackend *blk, size_t size) | |
2369 | { | |
2370 | IO_CODE(); | |
2371 | return qemu_blockalign(blk ? blk_bs(blk) : NULL, size); | |
2372 | } | |
2373 | ||
2374 | bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp) | |
2375 | { | |
2376 | BlockDriverState *bs = blk_bs(blk); | |
2377 | GLOBAL_STATE_CODE(); | |
2378 | GRAPH_RDLOCK_GUARD_MAINLOOP(); | |
2379 | ||
2380 | if (!bs) { | |
2381 | return false; | |
2382 | } | |
2383 | ||
2384 | return bdrv_op_is_blocked(bs, op, errp); | |
2385 | } | |
2386 | ||
2387 | void blk_op_unblock(BlockBackend *blk, BlockOpType op, Error *reason) | |
2388 | { | |
2389 | BlockDriverState *bs = blk_bs(blk); | |
2390 | GLOBAL_STATE_CODE(); | |
2391 | ||
2392 | if (bs) { | |
2393 | bdrv_op_unblock(bs, op, reason); | |
2394 | } | |
2395 | } | |
2396 | ||
2397 | void blk_op_block_all(BlockBackend *blk, Error *reason) | |
2398 | { | |
2399 | BlockDriverState *bs = blk_bs(blk); | |
2400 | GLOBAL_STATE_CODE(); | |
2401 | ||
2402 | if (bs) { | |
2403 | bdrv_op_block_all(bs, reason); | |
2404 | } | |
2405 | } | |
2406 | ||
2407 | void blk_op_unblock_all(BlockBackend *blk, Error *reason) | |
2408 | { | |
2409 | BlockDriverState *bs = blk_bs(blk); | |
2410 | GLOBAL_STATE_CODE(); | |
2411 | ||
2412 | if (bs) { | |
2413 | bdrv_op_unblock_all(bs, reason); | |
2414 | } | |
2415 | } | |
2416 | ||
2417 | AioContext *blk_get_aio_context(BlockBackend *blk) | |
2418 | { | |
2419 | BlockDriverState *bs; | |
2420 | IO_CODE(); | |
2421 | ||
2422 | if (!blk) { | |
2423 | return qemu_get_aio_context(); | |
2424 | } | |
2425 | ||
2426 | bs = blk_bs(blk); | |
2427 | if (bs) { | |
2428 | AioContext *ctx = bdrv_get_aio_context(blk_bs(blk)); | |
2429 | assert(ctx == blk->ctx); | |
2430 | } | |
2431 | ||
2432 | return blk->ctx; | |
2433 | } | |
2434 | ||
2435 | int blk_set_aio_context(BlockBackend *blk, AioContext *new_context, | |
2436 | Error **errp) | |
2437 | { | |
2438 | bool old_allow_change; | |
2439 | BlockDriverState *bs = blk_bs(blk); | |
2440 | int ret; | |
2441 | ||
2442 | GLOBAL_STATE_CODE(); | |
2443 | ||
2444 | if (!bs) { | |
2445 | blk->ctx = new_context; | |
2446 | return 0; | |
2447 | } | |
2448 | ||
2449 | bdrv_ref(bs); | |
2450 | ||
2451 | old_allow_change = blk->allow_aio_context_change; | |
2452 | blk->allow_aio_context_change = true; | |
2453 | ||
2454 | ret = bdrv_try_change_aio_context(bs, new_context, NULL, errp); | |
2455 | ||
2456 | blk->allow_aio_context_change = old_allow_change; | |
2457 | ||
2458 | bdrv_unref(bs); | |
2459 | return ret; | |
2460 | } | |
2461 | ||
2462 | typedef struct BdrvStateBlkRootContext { | |
2463 | AioContext *new_ctx; | |
2464 | BlockBackend *blk; | |
2465 | } BdrvStateBlkRootContext; | |
2466 | ||
2467 | static void blk_root_set_aio_ctx_commit(void *opaque) | |
2468 | { | |
2469 | BdrvStateBlkRootContext *s = opaque; | |
2470 | BlockBackend *blk = s->blk; | |
2471 | AioContext *new_context = s->new_ctx; | |
2472 | ThrottleGroupMember *tgm = &blk->public.throttle_group_member; | |
2473 | ||
2474 | blk->ctx = new_context; | |
2475 | if (tgm->throttle_state) { | |
2476 | throttle_group_detach_aio_context(tgm); | |
2477 | throttle_group_attach_aio_context(tgm, new_context); | |
2478 | } | |
2479 | } | |
2480 | ||
2481 | static TransactionActionDrv set_blk_root_context = { | |
2482 | .commit = blk_root_set_aio_ctx_commit, | |
2483 | .clean = g_free, | |
2484 | }; | |
2485 | ||
2486 | static bool blk_root_change_aio_ctx(BdrvChild *child, AioContext *ctx, | |
2487 | GHashTable *visited, Transaction *tran, | |
2488 | Error **errp) | |
2489 | { | |
2490 | BlockBackend *blk = child->opaque; | |
2491 | BdrvStateBlkRootContext *s; | |
2492 | ||
2493 | if (!blk->allow_aio_context_change) { | |
2494 | /* | |
2495 | * Manually created BlockBackends (those with a name) that are not | |
2496 | * attached to anything can change their AioContext without updating | |
2497 | * their user; return an error for others. | |
2498 | */ | |
2499 | if (!blk->name || blk->dev) { | |
2500 | /* TODO Add BB name/QOM path */ | |
2501 | error_setg(errp, "Cannot change iothread of active block backend"); | |
2502 | return false; | |
2503 | } | |
2504 | } | |
2505 | ||
2506 | s = g_new(BdrvStateBlkRootContext, 1); | |
2507 | *s = (BdrvStateBlkRootContext) { | |
2508 | .new_ctx = ctx, | |
2509 | .blk = blk, | |
2510 | }; | |
2511 | ||
2512 | tran_add(tran, &set_blk_root_context, s); | |
2513 | return true; | |
2514 | } | |
2515 | ||
2516 | void blk_add_aio_context_notifier(BlockBackend *blk, | |
2517 | void (*attached_aio_context)(AioContext *new_context, void *opaque), | |
2518 | void (*detach_aio_context)(void *opaque), void *opaque) | |
2519 | { | |
2520 | BlockBackendAioNotifier *notifier; | |
2521 | BlockDriverState *bs = blk_bs(blk); | |
2522 | GLOBAL_STATE_CODE(); | |
2523 | ||
2524 | notifier = g_new(BlockBackendAioNotifier, 1); | |
2525 | notifier->attached_aio_context = attached_aio_context; | |
2526 | notifier->detach_aio_context = detach_aio_context; | |
2527 | notifier->opaque = opaque; | |
2528 | QLIST_INSERT_HEAD(&blk->aio_notifiers, notifier, list); | |
2529 | ||
2530 | if (bs) { | |
2531 | bdrv_add_aio_context_notifier(bs, attached_aio_context, | |
2532 | detach_aio_context, opaque); | |
2533 | } | |
2534 | } | |
2535 | ||
2536 | void blk_remove_aio_context_notifier(BlockBackend *blk, | |
2537 | void (*attached_aio_context)(AioContext *, | |
2538 | void *), | |
2539 | void (*detach_aio_context)(void *), | |
2540 | void *opaque) | |
2541 | { | |
2542 | BlockBackendAioNotifier *notifier; | |
2543 | BlockDriverState *bs = blk_bs(blk); | |
2544 | ||
2545 | GLOBAL_STATE_CODE(); | |
2546 | ||
2547 | if (bs) { | |
2548 | bdrv_remove_aio_context_notifier(bs, attached_aio_context, | |
2549 | detach_aio_context, opaque); | |
2550 | } | |
2551 | ||
2552 | QLIST_FOREACH(notifier, &blk->aio_notifiers, list) { | |
2553 | if (notifier->attached_aio_context == attached_aio_context && | |
2554 | notifier->detach_aio_context == detach_aio_context && | |
2555 | notifier->opaque == opaque) { | |
2556 | QLIST_REMOVE(notifier, list); | |
2557 | g_free(notifier); | |
2558 | return; | |
2559 | } | |
2560 | } | |
2561 | ||
2562 | abort(); | |
2563 | } | |
2564 | ||
2565 | void blk_add_remove_bs_notifier(BlockBackend *blk, Notifier *notify) | |
2566 | { | |
2567 | GLOBAL_STATE_CODE(); | |
2568 | notifier_list_add(&blk->remove_bs_notifiers, notify); | |
2569 | } | |
2570 | ||
2571 | void blk_add_insert_bs_notifier(BlockBackend *blk, Notifier *notify) | |
2572 | { | |
2573 | GLOBAL_STATE_CODE(); | |
2574 | notifier_list_add(&blk->insert_bs_notifiers, notify); | |
2575 | } | |
2576 | ||
2577 | BlockAcctStats *blk_get_stats(BlockBackend *blk) | |
2578 | { | |
2579 | IO_CODE(); | |
2580 | return &blk->stats; | |
2581 | } | |
2582 | ||
2583 | void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk, | |
2584 | BlockCompletionFunc *cb, void *opaque) | |
2585 | { | |
2586 | IO_CODE(); | |
2587 | return qemu_aio_get(aiocb_info, blk_bs(blk), cb, opaque); | |
2588 | } | |
2589 | ||
2590 | int coroutine_fn blk_co_pwrite_zeroes(BlockBackend *blk, int64_t offset, | |
2591 | int64_t bytes, BdrvRequestFlags flags) | |
2592 | { | |
2593 | IO_OR_GS_CODE(); | |
2594 | return blk_co_pwritev(blk, offset, bytes, NULL, | |
2595 | flags | BDRV_REQ_ZERO_WRITE); | |
2596 | } | |
2597 | ||
2598 | int coroutine_fn blk_co_pwrite_compressed(BlockBackend *blk, int64_t offset, | |
2599 | int64_t bytes, const void *buf) | |
2600 | { | |
2601 | QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); | |
2602 | IO_OR_GS_CODE(); | |
2603 | return blk_co_pwritev_part(blk, offset, bytes, &qiov, 0, | |
2604 | BDRV_REQ_WRITE_COMPRESSED); | |
2605 | } | |
2606 | ||
2607 | int coroutine_fn blk_co_truncate(BlockBackend *blk, int64_t offset, bool exact, | |
2608 | PreallocMode prealloc, BdrvRequestFlags flags, | |
2609 | Error **errp) | |
2610 | { | |
2611 | IO_OR_GS_CODE(); | |
2612 | GRAPH_RDLOCK_GUARD(); | |
2613 | if (!blk_co_is_available(blk)) { | |
2614 | error_setg(errp, "No medium inserted"); | |
2615 | return -ENOMEDIUM; | |
2616 | } | |
2617 | ||
2618 | return bdrv_co_truncate(blk->root, offset, exact, prealloc, flags, errp); | |
2619 | } | |
2620 | ||
2621 | int blk_save_vmstate(BlockBackend *blk, const uint8_t *buf, | |
2622 | int64_t pos, int size) | |
2623 | { | |
2624 | int ret; | |
2625 | GLOBAL_STATE_CODE(); | |
2626 | ||
2627 | if (!blk_is_available(blk)) { | |
2628 | return -ENOMEDIUM; | |
2629 | } | |
2630 | ||
2631 | ret = bdrv_save_vmstate(blk_bs(blk), buf, pos, size); | |
2632 | if (ret < 0) { | |
2633 | return ret; | |
2634 | } | |
2635 | ||
2636 | if (ret == size && !blk->enable_write_cache) { | |
2637 | ret = bdrv_flush(blk_bs(blk)); | |
2638 | } | |
2639 | ||
2640 | return ret < 0 ? ret : size; | |
2641 | } | |
2642 | ||
2643 | int blk_load_vmstate(BlockBackend *blk, uint8_t *buf, int64_t pos, int size) | |
2644 | { | |
2645 | GLOBAL_STATE_CODE(); | |
2646 | if (!blk_is_available(blk)) { | |
2647 | return -ENOMEDIUM; | |
2648 | } | |
2649 | ||
2650 | return bdrv_load_vmstate(blk_bs(blk), buf, pos, size); | |
2651 | } | |
2652 | ||
2653 | int blk_probe_blocksizes(BlockBackend *blk, BlockSizes *bsz) | |
2654 | { | |
2655 | GLOBAL_STATE_CODE(); | |
2656 | GRAPH_RDLOCK_GUARD_MAINLOOP(); | |
2657 | ||
2658 | if (!blk_is_available(blk)) { | |
2659 | return -ENOMEDIUM; | |
2660 | } | |
2661 | ||
2662 | return bdrv_probe_blocksizes(blk_bs(blk), bsz); | |
2663 | } | |
2664 | ||
2665 | int blk_probe_geometry(BlockBackend *blk, HDGeometry *geo) | |
2666 | { | |
2667 | GLOBAL_STATE_CODE(); | |
2668 | if (!blk_is_available(blk)) { | |
2669 | return -ENOMEDIUM; | |
2670 | } | |
2671 | ||
2672 | return bdrv_probe_geometry(blk_bs(blk), geo); | |
2673 | } | |
2674 | ||
2675 | /* | |
2676 | * Updates the BlockBackendRootState object with data from the currently | |
2677 | * attached BlockDriverState. | |
2678 | */ | |
2679 | void blk_update_root_state(BlockBackend *blk) | |
2680 | { | |
2681 | GLOBAL_STATE_CODE(); | |
2682 | assert(blk->root); | |
2683 | ||
2684 | blk->root_state.open_flags = blk->root->bs->open_flags; | |
2685 | blk->root_state.detect_zeroes = blk->root->bs->detect_zeroes; | |
2686 | } | |
2687 | ||
2688 | /* | |
2689 | * Returns the detect-zeroes setting to be used for bdrv_open() of a | |
2690 | * BlockDriverState which is supposed to inherit the root state. | |
2691 | */ | |
2692 | bool blk_get_detect_zeroes_from_root_state(BlockBackend *blk) | |
2693 | { | |
2694 | GLOBAL_STATE_CODE(); | |
2695 | return blk->root_state.detect_zeroes; | |
2696 | } | |
2697 | ||
2698 | /* | |
2699 | * Returns the flags to be used for bdrv_open() of a BlockDriverState which is | |
2700 | * supposed to inherit the root state. | |
2701 | */ | |
2702 | int blk_get_open_flags_from_root_state(BlockBackend *blk) | |
2703 | { | |
2704 | GLOBAL_STATE_CODE(); | |
2705 | return blk->root_state.open_flags; | |
2706 | } | |
2707 | ||
2708 | BlockBackendRootState *blk_get_root_state(BlockBackend *blk) | |
2709 | { | |
2710 | GLOBAL_STATE_CODE(); | |
2711 | return &blk->root_state; | |
2712 | } | |
2713 | ||
2714 | int blk_commit_all(void) | |
2715 | { | |
2716 | BlockBackend *blk = NULL; | |
2717 | GLOBAL_STATE_CODE(); | |
2718 | GRAPH_RDLOCK_GUARD_MAINLOOP(); | |
2719 | ||
2720 | while ((blk = blk_all_next(blk)) != NULL) { | |
2721 | BlockDriverState *unfiltered_bs = bdrv_skip_filters(blk_bs(blk)); | |
2722 | ||
2723 | if (blk_is_inserted(blk) && bdrv_cow_child(unfiltered_bs)) { | |
2724 | int ret; | |
2725 | ||
2726 | ret = bdrv_commit(unfiltered_bs); | |
2727 | if (ret < 0) { | |
2728 | return ret; | |
2729 | } | |
2730 | } | |
2731 | } | |
2732 | return 0; | |
2733 | } | |
2734 | ||
2735 | ||
2736 | /* throttling disk I/O limits */ | |
2737 | void blk_set_io_limits(BlockBackend *blk, ThrottleConfig *cfg) | |
2738 | { | |
2739 | GLOBAL_STATE_CODE(); | |
2740 | throttle_group_config(&blk->public.throttle_group_member, cfg); | |
2741 | } | |
2742 | ||
2743 | void blk_io_limits_disable(BlockBackend *blk) | |
2744 | { | |
2745 | BlockDriverState *bs = blk_bs(blk); | |
2746 | ThrottleGroupMember *tgm = &blk->public.throttle_group_member; | |
2747 | assert(tgm->throttle_state); | |
2748 | GLOBAL_STATE_CODE(); | |
2749 | if (bs) { | |
2750 | bdrv_ref(bs); | |
2751 | bdrv_drained_begin(bs); | |
2752 | } | |
2753 | throttle_group_unregister_tgm(tgm); | |
2754 | if (bs) { | |
2755 | bdrv_drained_end(bs); | |
2756 | bdrv_unref(bs); | |
2757 | } | |
2758 | } | |
2759 | ||
2760 | /* should be called before blk_set_io_limits if a limit is set */ | |
2761 | void blk_io_limits_enable(BlockBackend *blk, const char *group) | |
2762 | { | |
2763 | assert(!blk->public.throttle_group_member.throttle_state); | |
2764 | GLOBAL_STATE_CODE(); | |
2765 | throttle_group_register_tgm(&blk->public.throttle_group_member, | |
2766 | group, blk_get_aio_context(blk)); | |
2767 | } | |
2768 | ||
2769 | void blk_io_limits_update_group(BlockBackend *blk, const char *group) | |
2770 | { | |
2771 | GLOBAL_STATE_CODE(); | |
2772 | /* this BB is not part of any group */ | |
2773 | if (!blk->public.throttle_group_member.throttle_state) { | |
2774 | return; | |
2775 | } | |
2776 | ||
2777 | /* this BB is a part of the same group than the one we want */ | |
2778 | if (!g_strcmp0(throttle_group_get_name(&blk->public.throttle_group_member), | |
2779 | group)) { | |
2780 | return; | |
2781 | } | |
2782 | ||
2783 | /* need to change the group this bs belong to */ | |
2784 | blk_io_limits_disable(blk); | |
2785 | blk_io_limits_enable(blk, group); | |
2786 | } | |
2787 | ||
2788 | static void blk_root_drained_begin(BdrvChild *child) | |
2789 | { | |
2790 | BlockBackend *blk = child->opaque; | |
2791 | ThrottleGroupMember *tgm = &blk->public.throttle_group_member; | |
2792 | ||
2793 | if (qatomic_fetch_inc(&blk->quiesce_counter) == 0) { | |
2794 | if (blk->dev_ops && blk->dev_ops->drained_begin) { | |
2795 | blk->dev_ops->drained_begin(blk->dev_opaque); | |
2796 | } | |
2797 | } | |
2798 | ||
2799 | /* Note that blk->root may not be accessible here yet if we are just | |
2800 | * attaching to a BlockDriverState that is drained. Use child instead. */ | |
2801 | ||
2802 | if (qatomic_fetch_inc(&tgm->io_limits_disabled) == 0) { | |
2803 | throttle_group_restart_tgm(tgm); | |
2804 | } | |
2805 | } | |
2806 | ||
2807 | static bool blk_root_drained_poll(BdrvChild *child) | |
2808 | { | |
2809 | BlockBackend *blk = child->opaque; | |
2810 | bool busy = false; | |
2811 | assert(qatomic_read(&blk->quiesce_counter)); | |
2812 | ||
2813 | if (blk->dev_ops && blk->dev_ops->drained_poll) { | |
2814 | busy = blk->dev_ops->drained_poll(blk->dev_opaque); | |
2815 | } | |
2816 | return busy || !!blk->in_flight; | |
2817 | } | |
2818 | ||
2819 | static void blk_root_drained_end(BdrvChild *child) | |
2820 | { | |
2821 | BlockBackend *blk = child->opaque; | |
2822 | assert(qatomic_read(&blk->quiesce_counter)); | |
2823 | ||
2824 | assert(blk->public.throttle_group_member.io_limits_disabled); | |
2825 | qatomic_dec(&blk->public.throttle_group_member.io_limits_disabled); | |
2826 | ||
2827 | if (qatomic_fetch_dec(&blk->quiesce_counter) == 1) { | |
2828 | if (blk->dev_ops && blk->dev_ops->drained_end) { | |
2829 | blk->dev_ops->drained_end(blk->dev_opaque); | |
2830 | } | |
2831 | qemu_mutex_lock(&blk->queued_requests_lock); | |
2832 | while (qemu_co_enter_next(&blk->queued_requests, | |
2833 | &blk->queued_requests_lock)) { | |
2834 | /* Resume all queued requests */ | |
2835 | } | |
2836 | qemu_mutex_unlock(&blk->queued_requests_lock); | |
2837 | } | |
2838 | } | |
2839 | ||
2840 | bool blk_register_buf(BlockBackend *blk, void *host, size_t size, Error **errp) | |
2841 | { | |
2842 | BlockDriverState *bs = blk_bs(blk); | |
2843 | ||
2844 | GLOBAL_STATE_CODE(); | |
2845 | ||
2846 | if (bs) { | |
2847 | return bdrv_register_buf(bs, host, size, errp); | |
2848 | } | |
2849 | return true; | |
2850 | } | |
2851 | ||
2852 | void blk_unregister_buf(BlockBackend *blk, void *host, size_t size) | |
2853 | { | |
2854 | BlockDriverState *bs = blk_bs(blk); | |
2855 | ||
2856 | GLOBAL_STATE_CODE(); | |
2857 | ||
2858 | if (bs) { | |
2859 | bdrv_unregister_buf(bs, host, size); | |
2860 | } | |
2861 | } | |
2862 | ||
2863 | int coroutine_fn blk_co_copy_range(BlockBackend *blk_in, int64_t off_in, | |
2864 | BlockBackend *blk_out, int64_t off_out, | |
2865 | int64_t bytes, BdrvRequestFlags read_flags, | |
2866 | BdrvRequestFlags write_flags) | |
2867 | { | |
2868 | int r; | |
2869 | IO_CODE(); | |
2870 | GRAPH_RDLOCK_GUARD(); | |
2871 | ||
2872 | r = blk_check_byte_request(blk_in, off_in, bytes); | |
2873 | if (r) { | |
2874 | return r; | |
2875 | } | |
2876 | r = blk_check_byte_request(blk_out, off_out, bytes); | |
2877 | if (r) { | |
2878 | return r; | |
2879 | } | |
2880 | ||
2881 | return bdrv_co_copy_range(blk_in->root, off_in, | |
2882 | blk_out->root, off_out, | |
2883 | bytes, read_flags, write_flags); | |
2884 | } | |
2885 | ||
2886 | const BdrvChild *blk_root(BlockBackend *blk) | |
2887 | { | |
2888 | GLOBAL_STATE_CODE(); | |
2889 | return blk->root; | |
2890 | } | |
2891 | ||
2892 | int blk_make_empty(BlockBackend *blk, Error **errp) | |
2893 | { | |
2894 | GLOBAL_STATE_CODE(); | |
2895 | GRAPH_RDLOCK_GUARD_MAINLOOP(); | |
2896 | ||
2897 | if (!blk_is_available(blk)) { | |
2898 | error_setg(errp, "No medium inserted"); | |
2899 | return -ENOMEDIUM; | |
2900 | } | |
2901 | ||
2902 | return bdrv_make_empty(blk->root, errp); | |
2903 | } |