4 * Copyright (C) 2014-2016 Red Hat, Inc.
7 * Markus Armbruster <armbru@redhat.com>,
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.
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"
26 #include "qemu/main-loop.h"
27 #include "qemu/option.h"
29 #include "migration/misc.h"
31 /* Number of coroutines to reserve per attached device model */
32 #define COROUTINE_POOL_RESERVATION 64
34 #define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */
36 static AioContext
*blk_aiocb_get_aio_context(BlockAIOCB
*acb
);
38 typedef struct BlockBackendAioNotifier
{
39 void (*attached_aio_context
)(AioContext
*new_context
, void *opaque
);
40 void (*detach_aio_context
)(void *opaque
);
42 QLIST_ENTRY(BlockBackendAioNotifier
) list
;
43 } BlockBackendAioNotifier
;
50 DriveInfo
*legacy_dinfo
; /* null unless created by drive_new() */
51 QTAILQ_ENTRY(BlockBackend
) link
; /* for block_backends */
52 QTAILQ_ENTRY(BlockBackend
) monitor_link
; /* for monitor_block_backends */
53 BlockBackendPublic
public;
55 DeviceState
*dev
; /* attached device model, if any */
56 const BlockDevOps
*dev_ops
;
59 /* If the BDS tree is removed, some of its options are stored here (which
60 * can be used to restore those options in the new BDS on insert) */
61 BlockBackendRootState root_state
;
63 bool enable_write_cache
;
65 /* I/O stats (display with "info blockstats"). */
68 BlockdevOnError on_read_error
, on_write_error
;
69 bool iostatus_enabled
;
70 BlockDeviceIoStatus iostatus
;
76 bool allow_aio_context_change
;
77 bool allow_write_beyond_eof
;
79 /* Protected by BQL */
80 NotifierList remove_bs_notifiers
, insert_bs_notifiers
;
81 QLIST_HEAD(, BlockBackendAioNotifier
) aio_notifiers
;
84 CoQueue queued_requests
;
85 bool disable_request_queuing
;
87 VMChangeStateEntry
*vmsh
;
88 bool force_allow_inactivate
;
90 /* Number of in-flight aio requests. BlockDriverState also counts
91 * in-flight requests but aio requests can exist even when blk->root is
92 * NULL, so we cannot rely on its counter for that case.
93 * Accessed with atomic ops.
95 unsigned int in_flight
;
98 typedef struct BlockBackendAIOCB
{
104 static const AIOCBInfo block_backend_aiocb_info
= {
105 .get_aio_context
= blk_aiocb_get_aio_context
,
106 .aiocb_size
= sizeof(BlockBackendAIOCB
),
109 static void drive_info_del(DriveInfo
*dinfo
);
110 static BlockBackend
*bdrv_first_blk(BlockDriverState
*bs
);
112 /* All BlockBackends. Protected by BQL. */
113 static QTAILQ_HEAD(, BlockBackend
) block_backends
=
114 QTAILQ_HEAD_INITIALIZER(block_backends
);
117 * All BlockBackends referenced by the monitor and which are iterated through by
118 * blk_next(). Protected by BQL.
120 static QTAILQ_HEAD(, BlockBackend
) monitor_block_backends
=
121 QTAILQ_HEAD_INITIALIZER(monitor_block_backends
);
123 static void blk_root_inherit_options(BdrvChildRole role
, bool parent_is_format
,
124 int *child_flags
, QDict
*child_options
,
125 int parent_flags
, QDict
*parent_options
)
127 /* We're not supposed to call this function for root nodes */
130 static void blk_root_drained_begin(BdrvChild
*child
);
131 static bool blk_root_drained_poll(BdrvChild
*child
);
132 static void blk_root_drained_end(BdrvChild
*child
, int *drained_end_counter
);
134 static void blk_root_change_media(BdrvChild
*child
, bool load
);
135 static void blk_root_resize(BdrvChild
*child
);
137 static bool blk_root_can_set_aio_ctx(BdrvChild
*child
, AioContext
*ctx
,
138 GSList
**ignore
, Error
**errp
);
139 static void blk_root_set_aio_ctx(BdrvChild
*child
, AioContext
*ctx
,
141 static bool blk_root_change_aio_ctx(BdrvChild
*child
, AioContext
*ctx
,
142 GHashTable
*visited
, Transaction
*tran
,
145 static char *blk_root_get_parent_desc(BdrvChild
*child
)
147 BlockBackend
*blk
= child
->opaque
;
148 g_autofree
char *dev_id
= NULL
;
151 return g_strdup_printf("block device '%s'", blk
->name
);
154 dev_id
= blk_get_attached_dev_id(blk
);
156 return g_strdup_printf("block device '%s'", dev_id
);
158 /* TODO Callback into the BB owner for something more detailed */
159 return g_strdup("an unnamed block device");
163 static const char *blk_root_get_name(BdrvChild
*child
)
165 return blk_name(child
->opaque
);
168 static void blk_vm_state_changed(void *opaque
, bool running
, RunState state
)
170 Error
*local_err
= NULL
;
171 BlockBackend
*blk
= opaque
;
173 if (state
== RUN_STATE_INMIGRATE
) {
177 qemu_del_vm_change_state_handler(blk
->vmsh
);
179 blk_set_perm(blk
, blk
->perm
, blk
->shared_perm
, &local_err
);
181 error_report_err(local_err
);
186 * Notifies the user of the BlockBackend that migration has completed. qdev
187 * devices can tighten their permissions in response (specifically revoke
188 * shared write permissions that we needed for storage migration).
190 * If an error is returned, the VM cannot be allowed to be resumed.
192 static void blk_root_activate(BdrvChild
*child
, Error
**errp
)
194 BlockBackend
*blk
= child
->opaque
;
195 Error
*local_err
= NULL
;
196 uint64_t saved_shared_perm
;
198 if (!blk
->disable_perm
) {
202 blk
->disable_perm
= false;
205 * blk->shared_perm contains the permissions we want to share once
206 * migration is really completely done. For now, we need to share
207 * all; but we also need to retain blk->shared_perm, which is
208 * overwritten by a successful blk_set_perm() call. Save it and
211 saved_shared_perm
= blk
->shared_perm
;
213 blk_set_perm(blk
, blk
->perm
, BLK_PERM_ALL
, &local_err
);
215 error_propagate(errp
, local_err
);
216 blk
->disable_perm
= true;
219 blk
->shared_perm
= saved_shared_perm
;
221 if (runstate_check(RUN_STATE_INMIGRATE
)) {
222 /* Activation can happen when migration process is still active, for
223 * example when nbd_server_add is called during non-shared storage
224 * migration. Defer the shared_perm update to migration completion. */
226 blk
->vmsh
= qemu_add_vm_change_state_handler(blk_vm_state_changed
,
232 blk_set_perm(blk
, blk
->perm
, blk
->shared_perm
, &local_err
);
234 error_propagate(errp
, local_err
);
235 blk
->disable_perm
= true;
240 void blk_set_force_allow_inactivate(BlockBackend
*blk
)
243 blk
->force_allow_inactivate
= true;
246 static bool blk_can_inactivate(BlockBackend
*blk
)
248 /* If it is a guest device, inactivate is ok. */
249 if (blk
->dev
|| blk_name(blk
)[0]) {
253 /* Inactivating means no more writes to the image can be done,
254 * even if those writes would be changes invisible to the
255 * guest. For block job BBs that satisfy this, we can just allow
256 * it. This is the case for mirror job source, which is required
257 * by libvirt non-shared block migration. */
258 if (!(blk
->perm
& (BLK_PERM_WRITE
| BLK_PERM_WRITE_UNCHANGED
))) {
262 return blk
->force_allow_inactivate
;
265 static int blk_root_inactivate(BdrvChild
*child
)
267 BlockBackend
*blk
= child
->opaque
;
269 if (blk
->disable_perm
) {
273 if (!blk_can_inactivate(blk
)) {
277 blk
->disable_perm
= true;
279 bdrv_child_try_set_perm(blk
->root
, 0, BLK_PERM_ALL
, &error_abort
);
285 static void blk_root_attach(BdrvChild
*child
)
287 BlockBackend
*blk
= child
->opaque
;
288 BlockBackendAioNotifier
*notifier
;
290 trace_blk_root_attach(child
, blk
, child
->bs
);
292 QLIST_FOREACH(notifier
, &blk
->aio_notifiers
, list
) {
293 bdrv_add_aio_context_notifier(child
->bs
,
294 notifier
->attached_aio_context
,
295 notifier
->detach_aio_context
,
300 static void blk_root_detach(BdrvChild
*child
)
302 BlockBackend
*blk
= child
->opaque
;
303 BlockBackendAioNotifier
*notifier
;
305 trace_blk_root_detach(child
, blk
, child
->bs
);
307 QLIST_FOREACH(notifier
, &blk
->aio_notifiers
, list
) {
308 bdrv_remove_aio_context_notifier(child
->bs
,
309 notifier
->attached_aio_context
,
310 notifier
->detach_aio_context
,
315 static AioContext
*blk_root_get_parent_aio_context(BdrvChild
*c
)
317 BlockBackend
*blk
= c
->opaque
;
319 return blk_get_aio_context(blk
);
322 static const BdrvChildClass child_root
= {
323 .inherit_options
= blk_root_inherit_options
,
325 .change_media
= blk_root_change_media
,
326 .resize
= blk_root_resize
,
327 .get_name
= blk_root_get_name
,
328 .get_parent_desc
= blk_root_get_parent_desc
,
330 .drained_begin
= blk_root_drained_begin
,
331 .drained_poll
= blk_root_drained_poll
,
332 .drained_end
= blk_root_drained_end
,
334 .activate
= blk_root_activate
,
335 .inactivate
= blk_root_inactivate
,
337 .attach
= blk_root_attach
,
338 .detach
= blk_root_detach
,
340 .can_set_aio_ctx
= blk_root_can_set_aio_ctx
,
341 .set_aio_ctx
= blk_root_set_aio_ctx
,
342 .change_aio_ctx
= blk_root_change_aio_ctx
,
344 .get_parent_aio_context
= blk_root_get_parent_aio_context
,
348 * Create a new BlockBackend with a reference count of one.
350 * @perm is a bitmasks of BLK_PERM_* constants which describes the permissions
351 * to request for a block driver node that is attached to this BlockBackend.
352 * @shared_perm is a bitmask which describes which permissions may be granted
353 * to other users of the attached node.
354 * Both sets of permissions can be changed later using blk_set_perm().
356 * Return the new BlockBackend on success, null on failure.
358 BlockBackend
*blk_new(AioContext
*ctx
, uint64_t perm
, uint64_t shared_perm
)
364 blk
= g_new0(BlockBackend
, 1);
368 blk
->shared_perm
= shared_perm
;
369 blk_set_enable_write_cache(blk
, true);
371 blk
->on_read_error
= BLOCKDEV_ON_ERROR_REPORT
;
372 blk
->on_write_error
= BLOCKDEV_ON_ERROR_ENOSPC
;
374 block_acct_init(&blk
->stats
);
376 qemu_co_queue_init(&blk
->queued_requests
);
377 notifier_list_init(&blk
->remove_bs_notifiers
);
378 notifier_list_init(&blk
->insert_bs_notifiers
);
379 QLIST_INIT(&blk
->aio_notifiers
);
381 QTAILQ_INSERT_TAIL(&block_backends
, blk
, link
);
386 * Create a new BlockBackend connected to an existing BlockDriverState.
388 * @perm is a bitmasks of BLK_PERM_* constants which describes the
389 * permissions to request for @bs that is attached to this
390 * BlockBackend. @shared_perm is a bitmask which describes which
391 * permissions may be granted to other users of the attached node.
392 * Both sets of permissions can be changed later using blk_set_perm().
394 * Return the new BlockBackend on success, null on failure.
396 BlockBackend
*blk_new_with_bs(BlockDriverState
*bs
, uint64_t perm
,
397 uint64_t shared_perm
, Error
**errp
)
399 BlockBackend
*blk
= blk_new(bdrv_get_aio_context(bs
), perm
, shared_perm
);
403 if (blk_insert_bs(blk
, bs
, errp
) < 0) {
411 * Creates a new BlockBackend, opens a new BlockDriverState, and connects both.
412 * The new BlockBackend is in the main AioContext.
414 * Just as with bdrv_open(), after having called this function the reference to
415 * @options belongs to the block layer (even on failure).
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
423 BlockBackend
*blk_new_open(const char *filename
, const char *reference
,
424 QDict
*options
, int flags
, Error
**errp
)
427 BlockDriverState
*bs
;
429 uint64_t shared
= BLK_PERM_ALL
;
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.
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.
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
;
450 if (flags
& BDRV_O_RESIZE
) {
451 perm
|= BLK_PERM_RESIZE
;
453 if (flags
& BDRV_O_NO_SHARE
) {
454 shared
= BLK_PERM_CONSISTENT_READ
| BLK_PERM_WRITE_UNCHANGED
;
457 blk
= blk_new(qemu_get_aio_context(), perm
, shared
);
458 bs
= bdrv_open(filename
, reference
, options
, flags
, errp
);
464 blk
->root
= bdrv_root_attach_child(bs
, "root", &child_root
,
465 BDRV_CHILD_FILTERED
| BDRV_CHILD_PRIMARY
,
466 perm
, shared
, blk
, errp
);
475 static void blk_delete(BlockBackend
*blk
)
477 assert(!blk
->refcnt
);
480 if (blk
->public.throttle_group_member
.throttle_state
) {
481 blk_io_limits_disable(blk
);
487 qemu_del_vm_change_state_handler(blk
->vmsh
);
490 assert(QLIST_EMPTY(&blk
->remove_bs_notifiers
.notifiers
));
491 assert(QLIST_EMPTY(&blk
->insert_bs_notifiers
.notifiers
));
492 assert(QLIST_EMPTY(&blk
->aio_notifiers
));
493 QTAILQ_REMOVE(&block_backends
, blk
, link
);
494 drive_info_del(blk
->legacy_dinfo
);
495 block_acct_cleanup(&blk
->stats
);
499 static void drive_info_del(DriveInfo
*dinfo
)
504 qemu_opts_del(dinfo
->opts
);
508 int blk_get_refcnt(BlockBackend
*blk
)
511 return blk
? blk
->refcnt
: 0;
515 * Increment @blk's reference count.
516 * @blk must not be null.
518 void blk_ref(BlockBackend
*blk
)
520 assert(blk
->refcnt
> 0);
526 * Decrement @blk's reference count.
527 * If this drops it to zero, destroy @blk.
528 * For convenience, do nothing if @blk is null.
530 void blk_unref(BlockBackend
*blk
)
534 assert(blk
->refcnt
> 0);
535 if (blk
->refcnt
> 1) {
539 /* blk_drain() cannot resurrect blk, nobody held a reference */
540 assert(blk
->refcnt
== 1);
548 * Behaves similarly to blk_next() but iterates over all BlockBackends, even the
549 * ones which are hidden (i.e. are not referenced by the monitor).
551 BlockBackend
*blk_all_next(BlockBackend
*blk
)
554 return blk
? QTAILQ_NEXT(blk
, link
)
555 : QTAILQ_FIRST(&block_backends
);
558 void blk_remove_all_bs(void)
560 BlockBackend
*blk
= NULL
;
564 while ((blk
= blk_all_next(blk
)) != NULL
) {
565 AioContext
*ctx
= blk_get_aio_context(blk
);
567 aio_context_acquire(ctx
);
571 aio_context_release(ctx
);
576 * Return the monitor-owned BlockBackend after @blk.
577 * If @blk is null, return the first one.
578 * Else, return @blk's next sibling, which may be null.
580 * To iterate over all BlockBackends, do
581 * for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
585 BlockBackend
*blk_next(BlockBackend
*blk
)
588 return blk
? QTAILQ_NEXT(blk
, monitor_link
)
589 : QTAILQ_FIRST(&monitor_block_backends
);
592 /* Iterates over all top-level BlockDriverStates, i.e. BDSs that are owned by
593 * the monitor or attached to a BlockBackend */
594 BlockDriverState
*bdrv_next(BdrvNextIterator
*it
)
596 BlockDriverState
*bs
, *old_bs
;
598 /* Must be called from the main loop */
599 assert(qemu_get_current_aio_context() == qemu_get_aio_context());
601 /* First, return all root nodes of BlockBackends. In order to avoid
602 * returning a BDS twice when multiple BBs refer to it, we only return it
603 * if the BB is the first one in the parent list of the BDS. */
604 if (it
->phase
== BDRV_NEXT_BACKEND_ROOTS
) {
605 BlockBackend
*old_blk
= it
->blk
;
607 old_bs
= old_blk
? blk_bs(old_blk
) : NULL
;
610 it
->blk
= blk_all_next(it
->blk
);
611 bs
= it
->blk
? blk_bs(it
->blk
) : NULL
;
612 } while (it
->blk
&& (bs
== NULL
|| bdrv_first_blk(bs
) != it
->blk
));
624 it
->phase
= BDRV_NEXT_MONITOR_OWNED
;
629 /* Then return the monitor-owned BDSes without a BB attached. Ignore all
630 * BDSes that are attached to a BlockBackend here; they have been handled
631 * by the above block already */
633 it
->bs
= bdrv_next_monitor_owned(it
->bs
);
635 } while (bs
&& bdrv_has_blk(bs
));
645 static void bdrv_next_reset(BdrvNextIterator
*it
)
647 *it
= (BdrvNextIterator
) {
648 .phase
= BDRV_NEXT_BACKEND_ROOTS
,
652 BlockDriverState
*bdrv_first(BdrvNextIterator
*it
)
656 return bdrv_next(it
);
659 /* Must be called when aborting a bdrv_next() iteration before
660 * bdrv_next() returns NULL */
661 void bdrv_next_cleanup(BdrvNextIterator
*it
)
663 /* Must be called from the main loop */
664 assert(qemu_get_current_aio_context() == qemu_get_aio_context());
666 if (it
->phase
== BDRV_NEXT_BACKEND_ROOTS
) {
668 bdrv_unref(blk_bs(it
->blk
));
679 * Add a BlockBackend into the list of backends referenced by the monitor, with
680 * the given @name acting as the handle for the monitor.
681 * Strictly for use by blockdev.c.
683 * @name must not be null or empty.
685 * Returns true on success and false on failure. In the latter case, an Error
686 * object is returned through @errp.
688 bool monitor_add_blk(BlockBackend
*blk
, const char *name
, Error
**errp
)
691 assert(name
&& name
[0]);
694 if (!id_wellformed(name
)) {
695 error_setg(errp
, "Invalid device name");
698 if (blk_by_name(name
)) {
699 error_setg(errp
, "Device with id '%s' already exists", name
);
702 if (bdrv_find_node(name
)) {
704 "Device name '%s' conflicts with an existing node name",
709 blk
->name
= g_strdup(name
);
710 QTAILQ_INSERT_TAIL(&monitor_block_backends
, blk
, monitor_link
);
715 * Remove a BlockBackend from the list of backends referenced by the monitor.
716 * Strictly for use by blockdev.c.
718 void monitor_remove_blk(BlockBackend
*blk
)
726 QTAILQ_REMOVE(&monitor_block_backends
, blk
, monitor_link
);
732 * Return @blk's name, a non-null string.
733 * Returns an empty string iff @blk is not referenced by the monitor.
735 const char *blk_name(const BlockBackend
*blk
)
738 return blk
->name
?: "";
742 * Return the BlockBackend with name @name if it exists, else null.
743 * @name must not be null.
745 BlockBackend
*blk_by_name(const char *name
)
747 BlockBackend
*blk
= NULL
;
751 while ((blk
= blk_next(blk
)) != NULL
) {
752 if (!strcmp(name
, blk
->name
)) {
760 * Return the BlockDriverState attached to @blk if any, else null.
762 BlockDriverState
*blk_bs(BlockBackend
*blk
)
765 return blk
->root
? blk
->root
->bs
: NULL
;
768 static BlockBackend
*bdrv_first_blk(BlockDriverState
*bs
)
774 QLIST_FOREACH(child
, &bs
->parents
, next_parent
) {
775 if (child
->klass
== &child_root
) {
776 return child
->opaque
;
784 * Returns true if @bs has an associated BlockBackend.
786 bool bdrv_has_blk(BlockDriverState
*bs
)
789 return bdrv_first_blk(bs
) != NULL
;
793 * Returns true if @bs has only BlockBackends as parents.
795 bool bdrv_is_root_node(BlockDriverState
*bs
)
800 QLIST_FOREACH(c
, &bs
->parents
, next_parent
) {
801 if (c
->klass
!= &child_root
) {
810 * Return @blk's DriveInfo if any, else null.
812 DriveInfo
*blk_legacy_dinfo(BlockBackend
*blk
)
815 return blk
->legacy_dinfo
;
819 * Set @blk's DriveInfo to @dinfo, and return it.
820 * @blk must not have a DriveInfo set already.
821 * No other BlockBackend may have the same DriveInfo set.
823 DriveInfo
*blk_set_legacy_dinfo(BlockBackend
*blk
, DriveInfo
*dinfo
)
825 assert(!blk
->legacy_dinfo
);
827 return blk
->legacy_dinfo
= dinfo
;
831 * Return the BlockBackend with DriveInfo @dinfo.
834 BlockBackend
*blk_by_legacy_dinfo(DriveInfo
*dinfo
)
836 BlockBackend
*blk
= NULL
;
839 while ((blk
= blk_next(blk
)) != NULL
) {
840 if (blk
->legacy_dinfo
== dinfo
) {
848 * Returns a pointer to the publicly accessible fields of @blk.
850 BlockBackendPublic
*blk_get_public(BlockBackend
*blk
)
857 * Returns a BlockBackend given the associated @public fields.
859 BlockBackend
*blk_by_public(BlockBackendPublic
*public)
862 return container_of(public, BlockBackend
, public);
866 * Disassociates the currently associated BlockDriverState from @blk.
868 void blk_remove_bs(BlockBackend
*blk
)
870 ThrottleGroupMember
*tgm
= &blk
->public.throttle_group_member
;
875 notifier_list_notify(&blk
->remove_bs_notifiers
, blk
);
876 if (tgm
->throttle_state
) {
877 BlockDriverState
*bs
= blk_bs(blk
);
880 * Take a ref in case blk_bs() changes across bdrv_drained_begin(), for
881 * example, if a temporary filter node is removed by a blockjob.
884 bdrv_drained_begin(bs
);
885 throttle_group_detach_aio_context(tgm
);
886 throttle_group_attach_aio_context(tgm
, qemu_get_aio_context());
887 bdrv_drained_end(bs
);
891 blk_update_root_state(blk
);
893 /* bdrv_root_unref_child() will cause blk->root to become stale and may
894 * switch to a completion coroutine later on. Let's drain all I/O here
895 * to avoid that and a potential QEMU crash.
900 bdrv_root_unref_child(root
);
904 * Associates a new BlockDriverState with @blk.
906 int blk_insert_bs(BlockBackend
*blk
, BlockDriverState
*bs
, Error
**errp
)
908 ThrottleGroupMember
*tgm
= &blk
->public.throttle_group_member
;
911 blk
->root
= bdrv_root_attach_child(bs
, "root", &child_root
,
912 BDRV_CHILD_FILTERED
| BDRV_CHILD_PRIMARY
,
913 blk
->perm
, blk
->shared_perm
,
915 if (blk
->root
== NULL
) {
919 notifier_list_notify(&blk
->insert_bs_notifiers
, blk
);
920 if (tgm
->throttle_state
) {
921 throttle_group_detach_aio_context(tgm
);
922 throttle_group_attach_aio_context(tgm
, bdrv_get_aio_context(bs
));
929 * Change BlockDriverState associated with @blk.
931 int blk_replace_bs(BlockBackend
*blk
, BlockDriverState
*new_bs
, Error
**errp
)
934 return bdrv_replace_child_bs(blk
->root
, new_bs
, errp
);
938 * Sets the permission bitmasks that the user of the BlockBackend needs.
940 int blk_set_perm(BlockBackend
*blk
, uint64_t perm
, uint64_t shared_perm
,
946 if (blk
->root
&& !blk
->disable_perm
) {
947 ret
= bdrv_child_try_set_perm(blk
->root
, perm
, shared_perm
, errp
);
954 blk
->shared_perm
= shared_perm
;
959 void blk_get_perm(BlockBackend
*blk
, uint64_t *perm
, uint64_t *shared_perm
)
963 *shared_perm
= blk
->shared_perm
;
967 * Attach device model @dev to @blk.
968 * Return 0 on success, -EBUSY when a device model is attached already.
970 int blk_attach_dev(BlockBackend
*blk
, DeviceState
*dev
)
977 /* While migration is still incoming, we don't need to apply the
978 * permissions of guest device BlockBackends. We might still have a block
979 * job or NBD server writing to the image for storage migration. */
980 if (runstate_check(RUN_STATE_INMIGRATE
)) {
981 blk
->disable_perm
= true;
986 blk_iostatus_reset(blk
);
992 * Detach device model @dev from @blk.
993 * @dev must be currently attached to @blk.
995 void blk_detach_dev(BlockBackend
*blk
, DeviceState
*dev
)
997 assert(blk
->dev
== dev
);
1000 blk
->dev_ops
= NULL
;
1001 blk
->dev_opaque
= NULL
;
1002 blk_set_perm(blk
, 0, BLK_PERM_ALL
, &error_abort
);
1007 * Return the device model attached to @blk if any, else null.
1009 DeviceState
*blk_get_attached_dev(BlockBackend
*blk
)
1011 GLOBAL_STATE_CODE();
1015 /* Return the qdev ID, or if no ID is assigned the QOM path, of the block
1016 * device attached to the BlockBackend. */
1017 char *blk_get_attached_dev_id(BlockBackend
*blk
)
1019 DeviceState
*dev
= blk
->dev
;
1023 return g_strdup("");
1024 } else if (dev
->id
) {
1025 return g_strdup(dev
->id
);
1028 return object_get_canonical_path(OBJECT(dev
)) ?: g_strdup("");
1032 * Return the BlockBackend which has the device model @dev attached if it
1033 * exists, else null.
1035 * @dev must not be null.
1037 BlockBackend
*blk_by_dev(void *dev
)
1039 BlockBackend
*blk
= NULL
;
1041 GLOBAL_STATE_CODE();
1043 assert(dev
!= NULL
);
1044 while ((blk
= blk_all_next(blk
)) != NULL
) {
1045 if (blk
->dev
== dev
) {
1053 * Set @blk's device model callbacks to @ops.
1054 * @opaque is the opaque argument to pass to the callbacks.
1055 * This is for use by device models.
1057 void blk_set_dev_ops(BlockBackend
*blk
, const BlockDevOps
*ops
,
1060 GLOBAL_STATE_CODE();
1062 blk
->dev_opaque
= opaque
;
1064 /* Are we currently quiesced? Should we enforce this right now? */
1065 if (blk
->quiesce_counter
&& ops
&& ops
->drained_begin
) {
1066 ops
->drained_begin(opaque
);
1071 * Notify @blk's attached device model of media change.
1073 * If @load is true, notify of media load. This action can fail, meaning that
1074 * the medium cannot be loaded. @errp is set then.
1076 * If @load is false, notify of media eject. This can never fail.
1078 * Also send DEVICE_TRAY_MOVED events as appropriate.
1080 void blk_dev_change_media_cb(BlockBackend
*blk
, bool load
, Error
**errp
)
1082 GLOBAL_STATE_CODE();
1083 if (blk
->dev_ops
&& blk
->dev_ops
->change_media_cb
) {
1084 bool tray_was_open
, tray_is_open
;
1085 Error
*local_err
= NULL
;
1087 tray_was_open
= blk_dev_is_tray_open(blk
);
1088 blk
->dev_ops
->change_media_cb(blk
->dev_opaque
, load
, &local_err
);
1090 assert(load
== true);
1091 error_propagate(errp
, local_err
);
1094 tray_is_open
= blk_dev_is_tray_open(blk
);
1096 if (tray_was_open
!= tray_is_open
) {
1097 char *id
= blk_get_attached_dev_id(blk
);
1098 qapi_event_send_device_tray_moved(blk_name(blk
), id
, tray_is_open
);
1104 static void blk_root_change_media(BdrvChild
*child
, bool load
)
1106 blk_dev_change_media_cb(child
->opaque
, load
, NULL
);
1110 * Does @blk's attached device model have removable media?
1111 * %true if no device model is attached.
1113 bool blk_dev_has_removable_media(BlockBackend
*blk
)
1115 GLOBAL_STATE_CODE();
1116 return !blk
->dev
|| (blk
->dev_ops
&& blk
->dev_ops
->change_media_cb
);
1120 * Does @blk's attached device model have a tray?
1122 bool blk_dev_has_tray(BlockBackend
*blk
)
1125 return blk
->dev_ops
&& blk
->dev_ops
->is_tray_open
;
1129 * Notify @blk's attached device model of a media eject request.
1130 * If @force is true, the medium is about to be yanked out forcefully.
1132 void blk_dev_eject_request(BlockBackend
*blk
, bool force
)
1134 GLOBAL_STATE_CODE();
1135 if (blk
->dev_ops
&& blk
->dev_ops
->eject_request_cb
) {
1136 blk
->dev_ops
->eject_request_cb(blk
->dev_opaque
, force
);
1141 * Does @blk's attached device model have a tray, and is it open?
1143 bool blk_dev_is_tray_open(BlockBackend
*blk
)
1146 if (blk_dev_has_tray(blk
)) {
1147 return blk
->dev_ops
->is_tray_open(blk
->dev_opaque
);
1153 * Does @blk's attached device model have the medium locked?
1154 * %false if the device model has no such lock.
1156 bool blk_dev_is_medium_locked(BlockBackend
*blk
)
1158 GLOBAL_STATE_CODE();
1159 if (blk
->dev_ops
&& blk
->dev_ops
->is_medium_locked
) {
1160 return blk
->dev_ops
->is_medium_locked(blk
->dev_opaque
);
1166 * Notify @blk's attached device model of a backend size change.
1168 static void blk_root_resize(BdrvChild
*child
)
1170 BlockBackend
*blk
= child
->opaque
;
1172 if (blk
->dev_ops
&& blk
->dev_ops
->resize_cb
) {
1173 blk
->dev_ops
->resize_cb(blk
->dev_opaque
);
1177 void blk_iostatus_enable(BlockBackend
*blk
)
1179 GLOBAL_STATE_CODE();
1180 blk
->iostatus_enabled
= true;
1181 blk
->iostatus
= BLOCK_DEVICE_IO_STATUS_OK
;
1184 /* The I/O status is only enabled if the drive explicitly
1185 * enables it _and_ the VM is configured to stop on errors */
1186 bool blk_iostatus_is_enabled(const BlockBackend
*blk
)
1189 return (blk
->iostatus_enabled
&&
1190 (blk
->on_write_error
== BLOCKDEV_ON_ERROR_ENOSPC
||
1191 blk
->on_write_error
== BLOCKDEV_ON_ERROR_STOP
||
1192 blk
->on_read_error
== BLOCKDEV_ON_ERROR_STOP
));
1195 BlockDeviceIoStatus
blk_iostatus(const BlockBackend
*blk
)
1197 GLOBAL_STATE_CODE();
1198 return blk
->iostatus
;
1201 void blk_iostatus_disable(BlockBackend
*blk
)
1203 GLOBAL_STATE_CODE();
1204 blk
->iostatus_enabled
= false;
1207 void blk_iostatus_reset(BlockBackend
*blk
)
1209 GLOBAL_STATE_CODE();
1210 if (blk_iostatus_is_enabled(blk
)) {
1211 blk
->iostatus
= BLOCK_DEVICE_IO_STATUS_OK
;
1215 void blk_iostatus_set_err(BlockBackend
*blk
, int error
)
1218 assert(blk_iostatus_is_enabled(blk
));
1219 if (blk
->iostatus
== BLOCK_DEVICE_IO_STATUS_OK
) {
1220 blk
->iostatus
= error
== ENOSPC
? BLOCK_DEVICE_IO_STATUS_NOSPACE
:
1221 BLOCK_DEVICE_IO_STATUS_FAILED
;
1225 void blk_set_allow_write_beyond_eof(BlockBackend
*blk
, bool allow
)
1228 blk
->allow_write_beyond_eof
= allow
;
1231 void blk_set_allow_aio_context_change(BlockBackend
*blk
, bool allow
)
1234 blk
->allow_aio_context_change
= allow
;
1237 void blk_set_disable_request_queuing(BlockBackend
*blk
, bool disable
)
1240 blk
->disable_request_queuing
= disable
;
1243 static int blk_check_byte_request(BlockBackend
*blk
, int64_t offset
,
1252 if (!blk_is_available(blk
)) {
1260 if (!blk
->allow_write_beyond_eof
) {
1261 len
= blk_getlength(blk
);
1266 if (offset
> len
|| len
- offset
< bytes
) {
1274 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
1275 static void coroutine_fn
blk_wait_while_drained(BlockBackend
*blk
)
1277 assert(blk
->in_flight
> 0);
1279 if (blk
->quiesce_counter
&& !blk
->disable_request_queuing
) {
1280 blk_dec_in_flight(blk
);
1281 qemu_co_queue_wait(&blk
->queued_requests
, NULL
);
1282 blk_inc_in_flight(blk
);
1286 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
1287 static int coroutine_fn
1288 blk_co_do_preadv_part(BlockBackend
*blk
, int64_t offset
, int64_t bytes
,
1289 QEMUIOVector
*qiov
, size_t qiov_offset
,
1290 BdrvRequestFlags flags
)
1293 BlockDriverState
*bs
;
1296 blk_wait_while_drained(blk
);
1298 /* Call blk_bs() only after waiting, the graph may have changed */
1300 trace_blk_co_preadv(blk
, bs
, offset
, bytes
, flags
);
1302 ret
= blk_check_byte_request(blk
, offset
, bytes
);
1307 bdrv_inc_in_flight(bs
);
1309 /* throttling disk I/O */
1310 if (blk
->public.throttle_group_member
.throttle_state
) {
1311 throttle_group_co_io_limits_intercept(&blk
->public.throttle_group_member
,
1315 ret
= bdrv_co_preadv_part(blk
->root
, offset
, bytes
, qiov
, qiov_offset
,
1317 bdrv_dec_in_flight(bs
);
1321 int coroutine_fn
blk_co_pread(BlockBackend
*blk
, int64_t offset
, int64_t bytes
,
1322 void *buf
, BdrvRequestFlags flags
)
1324 QEMUIOVector qiov
= QEMU_IOVEC_INIT_BUF(qiov
, buf
, bytes
);
1327 assert(bytes
<= SIZE_MAX
);
1329 return blk_co_preadv(blk
, offset
, bytes
, &qiov
, flags
);
1332 int coroutine_fn
blk_co_preadv(BlockBackend
*blk
, int64_t offset
,
1333 int64_t bytes
, QEMUIOVector
*qiov
,
1334 BdrvRequestFlags flags
)
1339 blk_inc_in_flight(blk
);
1340 ret
= blk_co_do_preadv_part(blk
, offset
, bytes
, qiov
, 0, flags
);
1341 blk_dec_in_flight(blk
);
1346 int coroutine_fn
blk_co_preadv_part(BlockBackend
*blk
, int64_t offset
,
1347 int64_t bytes
, QEMUIOVector
*qiov
,
1348 size_t qiov_offset
, BdrvRequestFlags flags
)
1353 blk_inc_in_flight(blk
);
1354 ret
= blk_co_do_preadv_part(blk
, offset
, bytes
, qiov
, qiov_offset
, flags
);
1355 blk_dec_in_flight(blk
);
1360 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
1361 static int coroutine_fn
1362 blk_co_do_pwritev_part(BlockBackend
*blk
, int64_t offset
, int64_t bytes
,
1363 QEMUIOVector
*qiov
, size_t qiov_offset
,
1364 BdrvRequestFlags flags
)
1367 BlockDriverState
*bs
;
1370 blk_wait_while_drained(blk
);
1372 /* Call blk_bs() only after waiting, the graph may have changed */
1374 trace_blk_co_pwritev(blk
, bs
, offset
, bytes
, flags
);
1376 ret
= blk_check_byte_request(blk
, offset
, bytes
);
1381 bdrv_inc_in_flight(bs
);
1382 /* throttling disk I/O */
1383 if (blk
->public.throttle_group_member
.throttle_state
) {
1384 throttle_group_co_io_limits_intercept(&blk
->public.throttle_group_member
,
1388 if (!blk
->enable_write_cache
) {
1389 flags
|= BDRV_REQ_FUA
;
1392 ret
= bdrv_co_pwritev_part(blk
->root
, offset
, bytes
, qiov
, qiov_offset
,
1394 bdrv_dec_in_flight(bs
);
1398 int coroutine_fn
blk_co_pwritev_part(BlockBackend
*blk
, int64_t offset
,
1400 QEMUIOVector
*qiov
, size_t qiov_offset
,
1401 BdrvRequestFlags flags
)
1406 blk_inc_in_flight(blk
);
1407 ret
= blk_co_do_pwritev_part(blk
, offset
, bytes
, qiov
, qiov_offset
, flags
);
1408 blk_dec_in_flight(blk
);
1413 int coroutine_fn
blk_co_pwrite(BlockBackend
*blk
, int64_t offset
, int64_t bytes
,
1414 const void *buf
, BdrvRequestFlags flags
)
1416 QEMUIOVector qiov
= QEMU_IOVEC_INIT_BUF(qiov
, buf
, bytes
);
1419 assert(bytes
<= SIZE_MAX
);
1421 return blk_co_pwritev(blk
, offset
, bytes
, &qiov
, flags
);
1424 int coroutine_fn
blk_co_pwritev(BlockBackend
*blk
, int64_t offset
,
1425 int64_t bytes
, QEMUIOVector
*qiov
,
1426 BdrvRequestFlags flags
)
1429 return blk_co_pwritev_part(blk
, offset
, bytes
, qiov
, 0, flags
);
1432 typedef struct BlkRwCo
{
1437 BdrvRequestFlags flags
;
1440 int blk_make_zero(BlockBackend
*blk
, BdrvRequestFlags flags
)
1442 GLOBAL_STATE_CODE();
1443 return bdrv_make_zero(blk
->root
, flags
);
1446 void blk_inc_in_flight(BlockBackend
*blk
)
1449 qatomic_inc(&blk
->in_flight
);
1452 void blk_dec_in_flight(BlockBackend
*blk
)
1455 qatomic_dec(&blk
->in_flight
);
1459 static void error_callback_bh(void *opaque
)
1461 struct BlockBackendAIOCB
*acb
= opaque
;
1463 blk_dec_in_flight(acb
->blk
);
1464 acb
->common
.cb(acb
->common
.opaque
, acb
->ret
);
1465 qemu_aio_unref(acb
);
1468 BlockAIOCB
*blk_abort_aio_request(BlockBackend
*blk
,
1469 BlockCompletionFunc
*cb
,
1470 void *opaque
, int ret
)
1472 struct BlockBackendAIOCB
*acb
;
1475 blk_inc_in_flight(blk
);
1476 acb
= blk_aio_get(&block_backend_aiocb_info
, blk
, cb
, opaque
);
1480 replay_bh_schedule_oneshot_event(blk_get_aio_context(blk
),
1481 error_callback_bh
, acb
);
1482 return &acb
->common
;
1485 typedef struct BlkAioEmAIOCB
{
1492 static AioContext
*blk_aio_em_aiocb_get_aio_context(BlockAIOCB
*acb_
)
1494 BlkAioEmAIOCB
*acb
= container_of(acb_
, BlkAioEmAIOCB
, common
);
1496 return blk_get_aio_context(acb
->rwco
.blk
);
1499 static const AIOCBInfo blk_aio_em_aiocb_info
= {
1500 .aiocb_size
= sizeof(BlkAioEmAIOCB
),
1501 .get_aio_context
= blk_aio_em_aiocb_get_aio_context
,
1504 static void blk_aio_complete(BlkAioEmAIOCB
*acb
)
1506 if (acb
->has_returned
) {
1507 acb
->common
.cb(acb
->common
.opaque
, acb
->rwco
.ret
);
1508 blk_dec_in_flight(acb
->rwco
.blk
);
1509 qemu_aio_unref(acb
);
1513 static void blk_aio_complete_bh(void *opaque
)
1515 BlkAioEmAIOCB
*acb
= opaque
;
1516 assert(acb
->has_returned
);
1517 blk_aio_complete(acb
);
1520 static BlockAIOCB
*blk_aio_prwv(BlockBackend
*blk
, int64_t offset
,
1522 void *iobuf
, CoroutineEntry co_entry
,
1523 BdrvRequestFlags flags
,
1524 BlockCompletionFunc
*cb
, void *opaque
)
1529 blk_inc_in_flight(blk
);
1530 acb
= blk_aio_get(&blk_aio_em_aiocb_info
, blk
, cb
, opaque
);
1531 acb
->rwco
= (BlkRwCo
) {
1539 acb
->has_returned
= false;
1541 co
= qemu_coroutine_create(co_entry
, acb
);
1542 bdrv_coroutine_enter(blk_bs(blk
), co
);
1544 acb
->has_returned
= true;
1545 if (acb
->rwco
.ret
!= NOT_DONE
) {
1546 replay_bh_schedule_oneshot_event(blk_get_aio_context(blk
),
1547 blk_aio_complete_bh
, acb
);
1550 return &acb
->common
;
1553 static void coroutine_fn
blk_aio_read_entry(void *opaque
)
1555 BlkAioEmAIOCB
*acb
= opaque
;
1556 BlkRwCo
*rwco
= &acb
->rwco
;
1557 QEMUIOVector
*qiov
= rwco
->iobuf
;
1559 assert(qiov
->size
== acb
->bytes
);
1560 rwco
->ret
= blk_co_do_preadv_part(rwco
->blk
, rwco
->offset
, acb
->bytes
, qiov
,
1562 blk_aio_complete(acb
);
1565 static void coroutine_fn
blk_aio_write_entry(void *opaque
)
1567 BlkAioEmAIOCB
*acb
= opaque
;
1568 BlkRwCo
*rwco
= &acb
->rwco
;
1569 QEMUIOVector
*qiov
= rwco
->iobuf
;
1571 assert(!qiov
|| qiov
->size
== acb
->bytes
);
1572 rwco
->ret
= blk_co_do_pwritev_part(rwco
->blk
, rwco
->offset
, acb
->bytes
,
1573 qiov
, 0, rwco
->flags
);
1574 blk_aio_complete(acb
);
1577 BlockAIOCB
*blk_aio_pwrite_zeroes(BlockBackend
*blk
, int64_t offset
,
1578 int64_t bytes
, BdrvRequestFlags flags
,
1579 BlockCompletionFunc
*cb
, void *opaque
)
1582 return blk_aio_prwv(blk
, offset
, bytes
, NULL
, blk_aio_write_entry
,
1583 flags
| BDRV_REQ_ZERO_WRITE
, cb
, opaque
);
1586 int64_t blk_getlength(BlockBackend
*blk
)
1589 if (!blk_is_available(blk
)) {
1593 return bdrv_getlength(blk_bs(blk
));
1596 void blk_get_geometry(BlockBackend
*blk
, uint64_t *nb_sectors_ptr
)
1600 *nb_sectors_ptr
= 0;
1602 bdrv_get_geometry(blk_bs(blk
), nb_sectors_ptr
);
1606 int64_t blk_nb_sectors(BlockBackend
*blk
)
1609 if (!blk_is_available(blk
)) {
1613 return bdrv_nb_sectors(blk_bs(blk
));
1616 BlockAIOCB
*blk_aio_preadv(BlockBackend
*blk
, int64_t offset
,
1617 QEMUIOVector
*qiov
, BdrvRequestFlags flags
,
1618 BlockCompletionFunc
*cb
, void *opaque
)
1621 assert((uint64_t)qiov
->size
<= INT64_MAX
);
1622 return blk_aio_prwv(blk
, offset
, qiov
->size
, qiov
,
1623 blk_aio_read_entry
, flags
, cb
, opaque
);
1626 BlockAIOCB
*blk_aio_pwritev(BlockBackend
*blk
, int64_t offset
,
1627 QEMUIOVector
*qiov
, BdrvRequestFlags flags
,
1628 BlockCompletionFunc
*cb
, void *opaque
)
1631 assert((uint64_t)qiov
->size
<= INT64_MAX
);
1632 return blk_aio_prwv(blk
, offset
, qiov
->size
, qiov
,
1633 blk_aio_write_entry
, flags
, cb
, opaque
);
1636 void blk_aio_cancel(BlockAIOCB
*acb
)
1638 GLOBAL_STATE_CODE();
1639 bdrv_aio_cancel(acb
);
1642 void blk_aio_cancel_async(BlockAIOCB
*acb
)
1645 bdrv_aio_cancel_async(acb
);
1648 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
1649 static int coroutine_fn
1650 blk_co_do_ioctl(BlockBackend
*blk
, unsigned long int req
, void *buf
)
1654 blk_wait_while_drained(blk
);
1656 if (!blk_is_available(blk
)) {
1660 return bdrv_co_ioctl(blk_bs(blk
), req
, buf
);
1663 int coroutine_fn
blk_co_ioctl(BlockBackend
*blk
, unsigned long int req
,
1669 blk_inc_in_flight(blk
);
1670 ret
= blk_co_do_ioctl(blk
, req
, buf
);
1671 blk_dec_in_flight(blk
);
1676 static void coroutine_fn
blk_aio_ioctl_entry(void *opaque
)
1678 BlkAioEmAIOCB
*acb
= opaque
;
1679 BlkRwCo
*rwco
= &acb
->rwco
;
1681 rwco
->ret
= blk_co_do_ioctl(rwco
->blk
, rwco
->offset
, rwco
->iobuf
);
1683 blk_aio_complete(acb
);
1686 BlockAIOCB
*blk_aio_ioctl(BlockBackend
*blk
, unsigned long int req
, void *buf
,
1687 BlockCompletionFunc
*cb
, void *opaque
)
1690 return blk_aio_prwv(blk
, req
, 0, buf
, blk_aio_ioctl_entry
, 0, cb
, opaque
);
1693 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
1694 static int coroutine_fn
1695 blk_co_do_pdiscard(BlockBackend
*blk
, int64_t offset
, int64_t bytes
)
1700 blk_wait_while_drained(blk
);
1702 ret
= blk_check_byte_request(blk
, offset
, bytes
);
1707 return bdrv_co_pdiscard(blk
->root
, offset
, bytes
);
1710 static void coroutine_fn
blk_aio_pdiscard_entry(void *opaque
)
1712 BlkAioEmAIOCB
*acb
= opaque
;
1713 BlkRwCo
*rwco
= &acb
->rwco
;
1715 rwco
->ret
= blk_co_do_pdiscard(rwco
->blk
, rwco
->offset
, acb
->bytes
);
1716 blk_aio_complete(acb
);
1719 BlockAIOCB
*blk_aio_pdiscard(BlockBackend
*blk
,
1720 int64_t offset
, int64_t bytes
,
1721 BlockCompletionFunc
*cb
, void *opaque
)
1724 return blk_aio_prwv(blk
, offset
, bytes
, NULL
, blk_aio_pdiscard_entry
, 0,
1728 int coroutine_fn
blk_co_pdiscard(BlockBackend
*blk
, int64_t offset
,
1734 blk_inc_in_flight(blk
);
1735 ret
= blk_co_do_pdiscard(blk
, offset
, bytes
);
1736 blk_dec_in_flight(blk
);
1741 /* To be called between exactly one pair of blk_inc/dec_in_flight() */
1742 static int coroutine_fn
blk_co_do_flush(BlockBackend
*blk
)
1744 blk_wait_while_drained(blk
);
1747 if (!blk_is_available(blk
)) {
1751 return bdrv_co_flush(blk_bs(blk
));
1754 static void coroutine_fn
blk_aio_flush_entry(void *opaque
)
1756 BlkAioEmAIOCB
*acb
= opaque
;
1757 BlkRwCo
*rwco
= &acb
->rwco
;
1759 rwco
->ret
= blk_co_do_flush(rwco
->blk
);
1760 blk_aio_complete(acb
);
1763 BlockAIOCB
*blk_aio_flush(BlockBackend
*blk
,
1764 BlockCompletionFunc
*cb
, void *opaque
)
1767 return blk_aio_prwv(blk
, 0, 0, NULL
, blk_aio_flush_entry
, 0, cb
, opaque
);
1770 int coroutine_fn
blk_co_flush(BlockBackend
*blk
)
1775 blk_inc_in_flight(blk
);
1776 ret
= blk_co_do_flush(blk
);
1777 blk_dec_in_flight(blk
);
1782 void blk_drain(BlockBackend
*blk
)
1784 BlockDriverState
*bs
= blk_bs(blk
);
1785 GLOBAL_STATE_CODE();
1789 bdrv_drained_begin(bs
);
1792 /* We may have -ENOMEDIUM completions in flight */
1793 AIO_WAIT_WHILE(blk_get_aio_context(blk
),
1794 qatomic_mb_read(&blk
->in_flight
) > 0);
1797 bdrv_drained_end(bs
);
1802 void blk_drain_all(void)
1804 BlockBackend
*blk
= NULL
;
1806 GLOBAL_STATE_CODE();
1808 bdrv_drain_all_begin();
1810 while ((blk
= blk_all_next(blk
)) != NULL
) {
1811 AioContext
*ctx
= blk_get_aio_context(blk
);
1813 aio_context_acquire(ctx
);
1815 /* We may have -ENOMEDIUM completions in flight */
1816 AIO_WAIT_WHILE(ctx
, qatomic_mb_read(&blk
->in_flight
) > 0);
1818 aio_context_release(ctx
);
1821 bdrv_drain_all_end();
1824 void blk_set_on_error(BlockBackend
*blk
, BlockdevOnError on_read_error
,
1825 BlockdevOnError on_write_error
)
1827 GLOBAL_STATE_CODE();
1828 blk
->on_read_error
= on_read_error
;
1829 blk
->on_write_error
= on_write_error
;
1832 BlockdevOnError
blk_get_on_error(BlockBackend
*blk
, bool is_read
)
1835 return is_read
? blk
->on_read_error
: blk
->on_write_error
;
1838 BlockErrorAction
blk_get_error_action(BlockBackend
*blk
, bool is_read
,
1841 BlockdevOnError on_err
= blk_get_on_error(blk
, is_read
);
1845 case BLOCKDEV_ON_ERROR_ENOSPC
:
1846 return (error
== ENOSPC
) ?
1847 BLOCK_ERROR_ACTION_STOP
: BLOCK_ERROR_ACTION_REPORT
;
1848 case BLOCKDEV_ON_ERROR_STOP
:
1849 return BLOCK_ERROR_ACTION_STOP
;
1850 case BLOCKDEV_ON_ERROR_REPORT
:
1851 return BLOCK_ERROR_ACTION_REPORT
;
1852 case BLOCKDEV_ON_ERROR_IGNORE
:
1853 return BLOCK_ERROR_ACTION_IGNORE
;
1854 case BLOCKDEV_ON_ERROR_AUTO
:
1860 static void send_qmp_error_event(BlockBackend
*blk
,
1861 BlockErrorAction action
,
1862 bool is_read
, int error
)
1864 IoOperationType optype
;
1865 BlockDriverState
*bs
= blk_bs(blk
);
1867 optype
= is_read
? IO_OPERATION_TYPE_READ
: IO_OPERATION_TYPE_WRITE
;
1868 qapi_event_send_block_io_error(blk_name(blk
), !!bs
,
1869 bs
? bdrv_get_node_name(bs
) : NULL
, optype
,
1870 action
, blk_iostatus_is_enabled(blk
),
1871 error
== ENOSPC
, strerror(error
));
1874 /* This is done by device models because, while the block layer knows
1875 * about the error, it does not know whether an operation comes from
1876 * the device or the block layer (from a job, for example).
1878 void blk_error_action(BlockBackend
*blk
, BlockErrorAction action
,
1879 bool is_read
, int error
)
1884 if (action
== BLOCK_ERROR_ACTION_STOP
) {
1885 /* First set the iostatus, so that "info block" returns an iostatus
1886 * that matches the events raised so far (an additional error iostatus
1887 * is fine, but not a lost one).
1889 blk_iostatus_set_err(blk
, error
);
1891 /* Then raise the request to stop the VM and the event.
1892 * qemu_system_vmstop_request_prepare has two effects. First,
1893 * it ensures that the STOP event always comes after the
1894 * BLOCK_IO_ERROR event. Second, it ensures that even if management
1895 * can observe the STOP event and do a "cont" before the STOP
1896 * event is issued, the VM will not stop. In this case, vm_start()
1897 * also ensures that the STOP/RESUME pair of events is emitted.
1899 qemu_system_vmstop_request_prepare();
1900 send_qmp_error_event(blk
, action
, is_read
, error
);
1901 qemu_system_vmstop_request(RUN_STATE_IO_ERROR
);
1903 send_qmp_error_event(blk
, action
, is_read
, error
);
1908 * Returns true if the BlockBackend can support taking write permissions
1909 * (because its root node is not read-only).
1911 bool blk_supports_write_perm(BlockBackend
*blk
)
1913 BlockDriverState
*bs
= blk_bs(blk
);
1914 GLOBAL_STATE_CODE();
1917 return !bdrv_is_read_only(bs
);
1919 return blk
->root_state
.open_flags
& BDRV_O_RDWR
;
1924 * Returns true if the BlockBackend can be written to in its current
1925 * configuration (i.e. if write permission have been requested)
1927 bool blk_is_writable(BlockBackend
*blk
)
1930 return blk
->perm
& BLK_PERM_WRITE
;
1933 bool blk_is_sg(BlockBackend
*blk
)
1935 BlockDriverState
*bs
= blk_bs(blk
);
1936 GLOBAL_STATE_CODE();
1942 return bdrv_is_sg(bs
);
1945 bool blk_enable_write_cache(BlockBackend
*blk
)
1948 return blk
->enable_write_cache
;
1951 void blk_set_enable_write_cache(BlockBackend
*blk
, bool wce
)
1953 GLOBAL_STATE_CODE();
1954 blk
->enable_write_cache
= wce
;
1957 void blk_activate(BlockBackend
*blk
, Error
**errp
)
1959 BlockDriverState
*bs
= blk_bs(blk
);
1960 GLOBAL_STATE_CODE();
1963 error_setg(errp
, "Device '%s' has no medium", blk
->name
);
1967 bdrv_activate(bs
, errp
);
1970 bool blk_is_inserted(BlockBackend
*blk
)
1972 BlockDriverState
*bs
= blk_bs(blk
);
1975 return bs
&& bdrv_is_inserted(bs
);
1978 bool blk_is_available(BlockBackend
*blk
)
1981 return blk_is_inserted(blk
) && !blk_dev_is_tray_open(blk
);
1984 void blk_lock_medium(BlockBackend
*blk
, bool locked
)
1986 BlockDriverState
*bs
= blk_bs(blk
);
1990 bdrv_lock_medium(bs
, locked
);
1994 void blk_eject(BlockBackend
*blk
, bool eject_flag
)
1996 BlockDriverState
*bs
= blk_bs(blk
);
2001 bdrv_eject(bs
, eject_flag
);
2004 /* Whether or not we ejected on the backend,
2005 * the frontend experienced a tray event. */
2006 id
= blk_get_attached_dev_id(blk
);
2007 qapi_event_send_device_tray_moved(blk_name(blk
), id
,
2012 int blk_get_flags(BlockBackend
*blk
)
2014 BlockDriverState
*bs
= blk_bs(blk
);
2015 GLOBAL_STATE_CODE();
2018 return bdrv_get_flags(bs
);
2020 return blk
->root_state
.open_flags
;
2024 /* Returns the minimum request alignment, in bytes; guaranteed nonzero */
2025 uint32_t blk_get_request_alignment(BlockBackend
*blk
)
2027 BlockDriverState
*bs
= blk_bs(blk
);
2029 return bs
? bs
->bl
.request_alignment
: BDRV_SECTOR_SIZE
;
2032 /* Returns the maximum hardware transfer length, in bytes; guaranteed nonzero */
2033 uint64_t blk_get_max_hw_transfer(BlockBackend
*blk
)
2035 BlockDriverState
*bs
= blk_bs(blk
);
2036 uint64_t max
= INT_MAX
;
2040 max
= MIN_NON_ZERO(max
, bs
->bl
.max_hw_transfer
);
2041 max
= MIN_NON_ZERO(max
, bs
->bl
.max_transfer
);
2043 return ROUND_DOWN(max
, blk_get_request_alignment(blk
));
2046 /* Returns the maximum transfer length, in bytes; guaranteed nonzero */
2047 uint32_t blk_get_max_transfer(BlockBackend
*blk
)
2049 BlockDriverState
*bs
= blk_bs(blk
);
2050 uint32_t max
= INT_MAX
;
2054 max
= MIN_NON_ZERO(max
, bs
->bl
.max_transfer
);
2056 return ROUND_DOWN(max
, blk_get_request_alignment(blk
));
2059 int blk_get_max_hw_iov(BlockBackend
*blk
)
2062 return MIN_NON_ZERO(blk
->root
->bs
->bl
.max_hw_iov
,
2063 blk
->root
->bs
->bl
.max_iov
);
2066 int blk_get_max_iov(BlockBackend
*blk
)
2069 return blk
->root
->bs
->bl
.max_iov
;
2072 void *blk_try_blockalign(BlockBackend
*blk
, size_t size
)
2075 return qemu_try_blockalign(blk
? blk_bs(blk
) : NULL
, size
);
2078 void *blk_blockalign(BlockBackend
*blk
, size_t size
)
2081 return qemu_blockalign(blk
? blk_bs(blk
) : NULL
, size
);
2084 bool blk_op_is_blocked(BlockBackend
*blk
, BlockOpType op
, Error
**errp
)
2086 BlockDriverState
*bs
= blk_bs(blk
);
2087 GLOBAL_STATE_CODE();
2093 return bdrv_op_is_blocked(bs
, op
, errp
);
2096 void blk_op_unblock(BlockBackend
*blk
, BlockOpType op
, Error
*reason
)
2098 BlockDriverState
*bs
= blk_bs(blk
);
2099 GLOBAL_STATE_CODE();
2102 bdrv_op_unblock(bs
, op
, reason
);
2106 void blk_op_block_all(BlockBackend
*blk
, Error
*reason
)
2108 BlockDriverState
*bs
= blk_bs(blk
);
2109 GLOBAL_STATE_CODE();
2112 bdrv_op_block_all(bs
, reason
);
2116 void blk_op_unblock_all(BlockBackend
*blk
, Error
*reason
)
2118 BlockDriverState
*bs
= blk_bs(blk
);
2119 GLOBAL_STATE_CODE();
2122 bdrv_op_unblock_all(bs
, reason
);
2126 AioContext
*blk_get_aio_context(BlockBackend
*blk
)
2128 BlockDriverState
*bs
= blk_bs(blk
);
2132 AioContext
*ctx
= bdrv_get_aio_context(blk_bs(blk
));
2133 assert(ctx
== blk
->ctx
);
2139 static AioContext
*blk_aiocb_get_aio_context(BlockAIOCB
*acb
)
2141 BlockBackendAIOCB
*blk_acb
= DO_UPCAST(BlockBackendAIOCB
, common
, acb
);
2142 return blk_get_aio_context(blk_acb
->blk
);
2145 static int blk_do_set_aio_context(BlockBackend
*blk
, AioContext
*new_context
,
2146 bool update_root_node
, Error
**errp
)
2148 BlockDriverState
*bs
= blk_bs(blk
);
2149 ThrottleGroupMember
*tgm
= &blk
->public.throttle_group_member
;
2155 if (update_root_node
) {
2156 ret
= bdrv_child_try_set_aio_context(bs
, new_context
, blk
->root
,
2163 if (tgm
->throttle_state
) {
2164 bdrv_drained_begin(bs
);
2165 throttle_group_detach_aio_context(tgm
);
2166 throttle_group_attach_aio_context(tgm
, new_context
);
2167 bdrv_drained_end(bs
);
2173 blk
->ctx
= new_context
;
2177 int blk_set_aio_context(BlockBackend
*blk
, AioContext
*new_context
,
2180 GLOBAL_STATE_CODE();
2181 return blk_do_set_aio_context(blk
, new_context
, true, errp
);
2184 typedef struct BdrvStateBlkRootContext
{
2185 AioContext
*new_ctx
;
2187 } BdrvStateBlkRootContext
;
2189 static void blk_root_set_aio_ctx_commit(void *opaque
)
2191 BdrvStateBlkRootContext
*s
= opaque
;
2192 BlockBackend
*blk
= s
->blk
;
2194 blk_do_set_aio_context(blk
, s
->new_ctx
, false, &error_abort
);
2197 static TransactionActionDrv set_blk_root_context
= {
2198 .commit
= blk_root_set_aio_ctx_commit
,
2202 static bool blk_root_change_aio_ctx(BdrvChild
*child
, AioContext
*ctx
,
2203 GHashTable
*visited
, Transaction
*tran
,
2206 BlockBackend
*blk
= child
->opaque
;
2207 BdrvStateBlkRootContext
*s
;
2209 if (!blk
->allow_aio_context_change
) {
2211 * Manually created BlockBackends (those with a name) that are not
2212 * attached to anything can change their AioContext without updating
2213 * their user; return an error for others.
2215 if (!blk
->name
|| blk
->dev
) {
2216 /* TODO Add BB name/QOM path */
2217 error_setg(errp
, "Cannot change iothread of active block backend");
2222 s
= g_new(BdrvStateBlkRootContext
, 1);
2223 *s
= (BdrvStateBlkRootContext
) {
2228 tran_add(tran
, &set_blk_root_context
, s
);
2232 static bool blk_root_can_set_aio_ctx(BdrvChild
*child
, AioContext
*ctx
,
2233 GSList
**ignore
, Error
**errp
)
2235 BlockBackend
*blk
= child
->opaque
;
2237 if (blk
->allow_aio_context_change
) {
2241 /* Only manually created BlockBackends that are not attached to anything
2242 * can change their AioContext without updating their user. */
2243 if (!blk
->name
|| blk
->dev
) {
2244 /* TODO Add BB name/QOM path */
2245 error_setg(errp
, "Cannot change iothread of active block backend");
2252 static void blk_root_set_aio_ctx(BdrvChild
*child
, AioContext
*ctx
,
2255 BlockBackend
*blk
= child
->opaque
;
2256 blk_do_set_aio_context(blk
, ctx
, false, &error_abort
);
2259 void blk_add_aio_context_notifier(BlockBackend
*blk
,
2260 void (*attached_aio_context
)(AioContext
*new_context
, void *opaque
),
2261 void (*detach_aio_context
)(void *opaque
), void *opaque
)
2263 BlockBackendAioNotifier
*notifier
;
2264 BlockDriverState
*bs
= blk_bs(blk
);
2265 GLOBAL_STATE_CODE();
2267 notifier
= g_new(BlockBackendAioNotifier
, 1);
2268 notifier
->attached_aio_context
= attached_aio_context
;
2269 notifier
->detach_aio_context
= detach_aio_context
;
2270 notifier
->opaque
= opaque
;
2271 QLIST_INSERT_HEAD(&blk
->aio_notifiers
, notifier
, list
);
2274 bdrv_add_aio_context_notifier(bs
, attached_aio_context
,
2275 detach_aio_context
, opaque
);
2279 void blk_remove_aio_context_notifier(BlockBackend
*blk
,
2280 void (*attached_aio_context
)(AioContext
*,
2282 void (*detach_aio_context
)(void *),
2285 BlockBackendAioNotifier
*notifier
;
2286 BlockDriverState
*bs
= blk_bs(blk
);
2288 GLOBAL_STATE_CODE();
2291 bdrv_remove_aio_context_notifier(bs
, attached_aio_context
,
2292 detach_aio_context
, opaque
);
2295 QLIST_FOREACH(notifier
, &blk
->aio_notifiers
, list
) {
2296 if (notifier
->attached_aio_context
== attached_aio_context
&&
2297 notifier
->detach_aio_context
== detach_aio_context
&&
2298 notifier
->opaque
== opaque
) {
2299 QLIST_REMOVE(notifier
, list
);
2308 void blk_add_remove_bs_notifier(BlockBackend
*blk
, Notifier
*notify
)
2310 GLOBAL_STATE_CODE();
2311 notifier_list_add(&blk
->remove_bs_notifiers
, notify
);
2314 void blk_add_insert_bs_notifier(BlockBackend
*blk
, Notifier
*notify
)
2316 GLOBAL_STATE_CODE();
2317 notifier_list_add(&blk
->insert_bs_notifiers
, notify
);
2320 void blk_io_plug(BlockBackend
*blk
)
2322 BlockDriverState
*bs
= blk_bs(blk
);
2330 void blk_io_unplug(BlockBackend
*blk
)
2332 BlockDriverState
*bs
= blk_bs(blk
);
2340 BlockAcctStats
*blk_get_stats(BlockBackend
*blk
)
2346 void *blk_aio_get(const AIOCBInfo
*aiocb_info
, BlockBackend
*blk
,
2347 BlockCompletionFunc
*cb
, void *opaque
)
2350 return qemu_aio_get(aiocb_info
, blk_bs(blk
), cb
, opaque
);
2353 int coroutine_fn
blk_co_pwrite_zeroes(BlockBackend
*blk
, int64_t offset
,
2354 int64_t bytes
, BdrvRequestFlags flags
)
2357 return blk_co_pwritev(blk
, offset
, bytes
, NULL
,
2358 flags
| BDRV_REQ_ZERO_WRITE
);
2361 int coroutine_fn
blk_co_pwrite_compressed(BlockBackend
*blk
, int64_t offset
,
2362 int64_t bytes
, const void *buf
)
2364 QEMUIOVector qiov
= QEMU_IOVEC_INIT_BUF(qiov
, buf
, bytes
);
2366 return blk_co_pwritev_part(blk
, offset
, bytes
, &qiov
, 0,
2367 BDRV_REQ_WRITE_COMPRESSED
);
2370 int coroutine_fn
blk_co_truncate(BlockBackend
*blk
, int64_t offset
, bool exact
,
2371 PreallocMode prealloc
, BdrvRequestFlags flags
,
2375 if (!blk_is_available(blk
)) {
2376 error_setg(errp
, "No medium inserted");
2380 return bdrv_co_truncate(blk
->root
, offset
, exact
, prealloc
, flags
, errp
);
2383 int blk_save_vmstate(BlockBackend
*blk
, const uint8_t *buf
,
2384 int64_t pos
, int size
)
2387 GLOBAL_STATE_CODE();
2389 if (!blk_is_available(blk
)) {
2393 ret
= bdrv_save_vmstate(blk_bs(blk
), buf
, pos
, size
);
2398 if (ret
== size
&& !blk
->enable_write_cache
) {
2399 ret
= bdrv_flush(blk_bs(blk
));
2402 return ret
< 0 ? ret
: size
;
2405 int blk_load_vmstate(BlockBackend
*blk
, uint8_t *buf
, int64_t pos
, int size
)
2407 GLOBAL_STATE_CODE();
2408 if (!blk_is_available(blk
)) {
2412 return bdrv_load_vmstate(blk_bs(blk
), buf
, pos
, size
);
2415 int blk_probe_blocksizes(BlockBackend
*blk
, BlockSizes
*bsz
)
2417 GLOBAL_STATE_CODE();
2418 if (!blk_is_available(blk
)) {
2422 return bdrv_probe_blocksizes(blk_bs(blk
), bsz
);
2425 int blk_probe_geometry(BlockBackend
*blk
, HDGeometry
*geo
)
2427 GLOBAL_STATE_CODE();
2428 if (!blk_is_available(blk
)) {
2432 return bdrv_probe_geometry(blk_bs(blk
), geo
);
2436 * Updates the BlockBackendRootState object with data from the currently
2437 * attached BlockDriverState.
2439 void blk_update_root_state(BlockBackend
*blk
)
2441 GLOBAL_STATE_CODE();
2444 blk
->root_state
.open_flags
= blk
->root
->bs
->open_flags
;
2445 blk
->root_state
.detect_zeroes
= blk
->root
->bs
->detect_zeroes
;
2449 * Returns the detect-zeroes setting to be used for bdrv_open() of a
2450 * BlockDriverState which is supposed to inherit the root state.
2452 bool blk_get_detect_zeroes_from_root_state(BlockBackend
*blk
)
2454 GLOBAL_STATE_CODE();
2455 return blk
->root_state
.detect_zeroes
;
2459 * Returns the flags to be used for bdrv_open() of a BlockDriverState which is
2460 * supposed to inherit the root state.
2462 int blk_get_open_flags_from_root_state(BlockBackend
*blk
)
2464 GLOBAL_STATE_CODE();
2465 return blk
->root_state
.open_flags
;
2468 BlockBackendRootState
*blk_get_root_state(BlockBackend
*blk
)
2470 GLOBAL_STATE_CODE();
2471 return &blk
->root_state
;
2474 int blk_commit_all(void)
2476 BlockBackend
*blk
= NULL
;
2477 GLOBAL_STATE_CODE();
2479 while ((blk
= blk_all_next(blk
)) != NULL
) {
2480 AioContext
*aio_context
= blk_get_aio_context(blk
);
2481 BlockDriverState
*unfiltered_bs
= bdrv_skip_filters(blk_bs(blk
));
2483 aio_context_acquire(aio_context
);
2484 if (blk_is_inserted(blk
) && bdrv_cow_child(unfiltered_bs
)) {
2487 ret
= bdrv_commit(unfiltered_bs
);
2489 aio_context_release(aio_context
);
2493 aio_context_release(aio_context
);
2499 /* throttling disk I/O limits */
2500 void blk_set_io_limits(BlockBackend
*blk
, ThrottleConfig
*cfg
)
2502 GLOBAL_STATE_CODE();
2503 throttle_group_config(&blk
->public.throttle_group_member
, cfg
);
2506 void blk_io_limits_disable(BlockBackend
*blk
)
2508 BlockDriverState
*bs
= blk_bs(blk
);
2509 ThrottleGroupMember
*tgm
= &blk
->public.throttle_group_member
;
2510 assert(tgm
->throttle_state
);
2511 GLOBAL_STATE_CODE();
2514 bdrv_drained_begin(bs
);
2516 throttle_group_unregister_tgm(tgm
);
2518 bdrv_drained_end(bs
);
2523 /* should be called before blk_set_io_limits if a limit is set */
2524 void blk_io_limits_enable(BlockBackend
*blk
, const char *group
)
2526 assert(!blk
->public.throttle_group_member
.throttle_state
);
2527 GLOBAL_STATE_CODE();
2528 throttle_group_register_tgm(&blk
->public.throttle_group_member
,
2529 group
, blk_get_aio_context(blk
));
2532 void blk_io_limits_update_group(BlockBackend
*blk
, const char *group
)
2534 GLOBAL_STATE_CODE();
2535 /* this BB is not part of any group */
2536 if (!blk
->public.throttle_group_member
.throttle_state
) {
2540 /* this BB is a part of the same group than the one we want */
2541 if (!g_strcmp0(throttle_group_get_name(&blk
->public.throttle_group_member
),
2546 /* need to change the group this bs belong to */
2547 blk_io_limits_disable(blk
);
2548 blk_io_limits_enable(blk
, group
);
2551 static void blk_root_drained_begin(BdrvChild
*child
)
2553 BlockBackend
*blk
= child
->opaque
;
2554 ThrottleGroupMember
*tgm
= &blk
->public.throttle_group_member
;
2556 if (++blk
->quiesce_counter
== 1) {
2557 if (blk
->dev_ops
&& blk
->dev_ops
->drained_begin
) {
2558 blk
->dev_ops
->drained_begin(blk
->dev_opaque
);
2562 /* Note that blk->root may not be accessible here yet if we are just
2563 * attaching to a BlockDriverState that is drained. Use child instead. */
2565 if (qatomic_fetch_inc(&tgm
->io_limits_disabled
) == 0) {
2566 throttle_group_restart_tgm(tgm
);
2570 static bool blk_root_drained_poll(BdrvChild
*child
)
2572 BlockBackend
*blk
= child
->opaque
;
2574 assert(blk
->quiesce_counter
);
2576 if (blk
->dev_ops
&& blk
->dev_ops
->drained_poll
) {
2577 busy
= blk
->dev_ops
->drained_poll(blk
->dev_opaque
);
2579 return busy
|| !!blk
->in_flight
;
2582 static void blk_root_drained_end(BdrvChild
*child
, int *drained_end_counter
)
2584 BlockBackend
*blk
= child
->opaque
;
2585 assert(blk
->quiesce_counter
);
2587 assert(blk
->public.throttle_group_member
.io_limits_disabled
);
2588 qatomic_dec(&blk
->public.throttle_group_member
.io_limits_disabled
);
2590 if (--blk
->quiesce_counter
== 0) {
2591 if (blk
->dev_ops
&& blk
->dev_ops
->drained_end
) {
2592 blk
->dev_ops
->drained_end(blk
->dev_opaque
);
2594 while (qemu_co_enter_next(&blk
->queued_requests
, NULL
)) {
2595 /* Resume all queued requests */
2600 void blk_register_buf(BlockBackend
*blk
, void *host
, size_t size
)
2602 GLOBAL_STATE_CODE();
2603 bdrv_register_buf(blk_bs(blk
), host
, size
);
2606 void blk_unregister_buf(BlockBackend
*blk
, void *host
)
2608 GLOBAL_STATE_CODE();
2609 bdrv_unregister_buf(blk_bs(blk
), host
);
2612 int coroutine_fn
blk_co_copy_range(BlockBackend
*blk_in
, int64_t off_in
,
2613 BlockBackend
*blk_out
, int64_t off_out
,
2614 int64_t bytes
, BdrvRequestFlags read_flags
,
2615 BdrvRequestFlags write_flags
)
2620 r
= blk_check_byte_request(blk_in
, off_in
, bytes
);
2624 r
= blk_check_byte_request(blk_out
, off_out
, bytes
);
2628 return bdrv_co_copy_range(blk_in
->root
, off_in
,
2629 blk_out
->root
, off_out
,
2630 bytes
, read_flags
, write_flags
);
2633 const BdrvChild
*blk_root(BlockBackend
*blk
)
2635 GLOBAL_STATE_CODE();
2639 int blk_make_empty(BlockBackend
*blk
, Error
**errp
)
2641 GLOBAL_STATE_CODE();
2642 if (!blk_is_available(blk
)) {
2643 error_setg(errp
, "No medium inserted");
2647 return bdrv_make_empty(blk
->root
, errp
);