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/throttle-groups.h"
18 #include "sysemu/blockdev.h"
19 #include "sysemu/sysemu.h"
20 #include "qapi-event.h"
24 /* Number of coroutines to reserve per attached device model */
25 #define COROUTINE_POOL_RESERVATION 64
27 #define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */
29 static AioContext
*blk_aiocb_get_aio_context(BlockAIOCB
*acb
);
35 DriveInfo
*legacy_dinfo
; /* null unless created by drive_new() */
36 QTAILQ_ENTRY(BlockBackend
) link
; /* for block_backends */
37 QTAILQ_ENTRY(BlockBackend
) monitor_link
; /* for monitor_block_backends */
38 BlockBackendPublic
public;
40 void *dev
; /* attached device model, if any */
41 bool legacy_dev
; /* true if dev is not a DeviceState */
42 /* TODO change to DeviceState when all users are qdevified */
43 const BlockDevOps
*dev_ops
;
46 /* the block size for which the guest device expects atomicity */
49 /* If the BDS tree is removed, some of its options are stored here (which
50 * can be used to restore those options in the new BDS on insert) */
51 BlockBackendRootState root_state
;
53 bool enable_write_cache
;
55 /* I/O stats (display with "info blockstats"). */
58 BlockdevOnError on_read_error
, on_write_error
;
59 bool iostatus_enabled
;
60 BlockDeviceIoStatus iostatus
;
65 bool allow_write_beyond_eof
;
67 NotifierList remove_bs_notifiers
, insert_bs_notifiers
;
72 typedef struct BlockBackendAIOCB
{
78 static const AIOCBInfo block_backend_aiocb_info
= {
79 .get_aio_context
= blk_aiocb_get_aio_context
,
80 .aiocb_size
= sizeof(BlockBackendAIOCB
),
83 static void drive_info_del(DriveInfo
*dinfo
);
84 static BlockBackend
*bdrv_first_blk(BlockDriverState
*bs
);
85 static char *blk_get_attached_dev_id(BlockBackend
*blk
);
87 /* All BlockBackends */
88 static QTAILQ_HEAD(, BlockBackend
) block_backends
=
89 QTAILQ_HEAD_INITIALIZER(block_backends
);
91 /* All BlockBackends referenced by the monitor and which are iterated through by
93 static QTAILQ_HEAD(, BlockBackend
) monitor_block_backends
=
94 QTAILQ_HEAD_INITIALIZER(monitor_block_backends
);
96 static void blk_root_inherit_options(int *child_flags
, QDict
*child_options
,
97 int parent_flags
, QDict
*parent_options
)
99 /* We're not supposed to call this function for root nodes */
102 static void blk_root_drained_begin(BdrvChild
*child
);
103 static void blk_root_drained_end(BdrvChild
*child
);
105 static void blk_root_change_media(BdrvChild
*child
, bool load
);
106 static void blk_root_resize(BdrvChild
*child
);
108 static char *blk_root_get_parent_desc(BdrvChild
*child
)
110 BlockBackend
*blk
= child
->opaque
;
114 return g_strdup(blk
->name
);
117 dev_id
= blk_get_attached_dev_id(blk
);
121 /* TODO Callback into the BB owner for something more detailed */
123 return g_strdup("a block device");
127 static const char *blk_root_get_name(BdrvChild
*child
)
129 return blk_name(child
->opaque
);
132 static const BdrvChildRole child_root
= {
133 .inherit_options
= blk_root_inherit_options
,
135 .change_media
= blk_root_change_media
,
136 .resize
= blk_root_resize
,
137 .get_name
= blk_root_get_name
,
138 .get_parent_desc
= blk_root_get_parent_desc
,
140 .drained_begin
= blk_root_drained_begin
,
141 .drained_end
= blk_root_drained_end
,
145 * Create a new BlockBackend with a reference count of one.
147 * @perm is a bitmasks of BLK_PERM_* constants which describes the permissions
148 * to request for a block driver node that is attached to this BlockBackend.
149 * @shared_perm is a bitmask which describes which permissions may be granted
150 * to other users of the attached node.
151 * Both sets of permissions can be changed later using blk_set_perm().
153 * Return the new BlockBackend on success, null on failure.
155 BlockBackend
*blk_new(uint64_t perm
, uint64_t shared_perm
)
159 blk
= g_new0(BlockBackend
, 1);
162 blk
->shared_perm
= shared_perm
;
163 blk_set_enable_write_cache(blk
, true);
165 qemu_co_queue_init(&blk
->public.throttled_reqs
[0]);
166 qemu_co_queue_init(&blk
->public.throttled_reqs
[1]);
168 notifier_list_init(&blk
->remove_bs_notifiers
);
169 notifier_list_init(&blk
->insert_bs_notifiers
);
171 QTAILQ_INSERT_TAIL(&block_backends
, blk
, link
);
176 * Creates a new BlockBackend, opens a new BlockDriverState, and connects both.
178 * Just as with bdrv_open(), after having called this function the reference to
179 * @options belongs to the block layer (even on failure).
181 * TODO: Remove @filename and @flags; it should be possible to specify a whole
182 * BDS tree just by specifying the @options QDict (or @reference,
183 * alternatively). At the time of adding this function, this is not possible,
184 * though, so callers of this function have to be able to specify @filename and
187 BlockBackend
*blk_new_open(const char *filename
, const char *reference
,
188 QDict
*options
, int flags
, Error
**errp
)
191 BlockDriverState
*bs
;
194 /* blk_new_open() is mainly used in .bdrv_create implementations and the
195 * tools where sharing isn't a concern because the BDS stays private, so we
196 * just request permission according to the flags.
198 * The exceptions are xen_disk and blockdev_init(); in these cases, the
199 * caller of blk_new_open() doesn't make use of the permissions, but they
200 * shouldn't hurt either. We can still share everything here because the
201 * guest devices will add their own blockers if they can't share. */
202 perm
= BLK_PERM_CONSISTENT_READ
;
203 if (flags
& BDRV_O_RDWR
) {
204 perm
|= BLK_PERM_WRITE
;
206 if (flags
& BDRV_O_RESIZE
) {
207 perm
|= BLK_PERM_RESIZE
;
210 blk
= blk_new(perm
, BLK_PERM_ALL
);
211 bs
= bdrv_open(filename
, reference
, options
, flags
, errp
);
217 blk
->root
= bdrv_root_attach_child(bs
, "root", &child_root
,
218 perm
, BLK_PERM_ALL
, blk
, errp
);
228 static void blk_delete(BlockBackend
*blk
)
230 assert(!blk
->refcnt
);
236 assert(QLIST_EMPTY(&blk
->remove_bs_notifiers
.notifiers
));
237 assert(QLIST_EMPTY(&blk
->insert_bs_notifiers
.notifiers
));
238 QTAILQ_REMOVE(&block_backends
, blk
, link
);
239 drive_info_del(blk
->legacy_dinfo
);
240 block_acct_cleanup(&blk
->stats
);
244 static void drive_info_del(DriveInfo
*dinfo
)
249 qemu_opts_del(dinfo
->opts
);
250 g_free(dinfo
->serial
);
254 int blk_get_refcnt(BlockBackend
*blk
)
256 return blk
? blk
->refcnt
: 0;
260 * Increment @blk's reference count.
261 * @blk must not be null.
263 void blk_ref(BlockBackend
*blk
)
269 * Decrement @blk's reference count.
270 * If this drops it to zero, destroy @blk.
271 * For convenience, do nothing if @blk is null.
273 void blk_unref(BlockBackend
*blk
)
276 assert(blk
->refcnt
> 0);
277 if (!--blk
->refcnt
) {
284 * Behaves similarly to blk_next() but iterates over all BlockBackends, even the
285 * ones which are hidden (i.e. are not referenced by the monitor).
287 static BlockBackend
*blk_all_next(BlockBackend
*blk
)
289 return blk
? QTAILQ_NEXT(blk
, link
)
290 : QTAILQ_FIRST(&block_backends
);
293 void blk_remove_all_bs(void)
295 BlockBackend
*blk
= NULL
;
297 while ((blk
= blk_all_next(blk
)) != NULL
) {
298 AioContext
*ctx
= blk_get_aio_context(blk
);
300 aio_context_acquire(ctx
);
304 aio_context_release(ctx
);
309 * Return the monitor-owned BlockBackend after @blk.
310 * If @blk is null, return the first one.
311 * Else, return @blk's next sibling, which may be null.
313 * To iterate over all BlockBackends, do
314 * for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
318 BlockBackend
*blk_next(BlockBackend
*blk
)
320 return blk
? QTAILQ_NEXT(blk
, monitor_link
)
321 : QTAILQ_FIRST(&monitor_block_backends
);
324 /* Iterates over all top-level BlockDriverStates, i.e. BDSs that are owned by
325 * the monitor or attached to a BlockBackend */
326 BlockDriverState
*bdrv_next(BdrvNextIterator
*it
)
328 BlockDriverState
*bs
;
330 /* First, return all root nodes of BlockBackends. In order to avoid
331 * returning a BDS twice when multiple BBs refer to it, we only return it
332 * if the BB is the first one in the parent list of the BDS. */
333 if (it
->phase
== BDRV_NEXT_BACKEND_ROOTS
) {
335 it
->blk
= blk_all_next(it
->blk
);
336 bs
= it
->blk
? blk_bs(it
->blk
) : NULL
;
337 } while (it
->blk
&& (bs
== NULL
|| bdrv_first_blk(bs
) != it
->blk
));
342 it
->phase
= BDRV_NEXT_MONITOR_OWNED
;
345 /* Then return the monitor-owned BDSes without a BB attached. Ignore all
346 * BDSes that are attached to a BlockBackend here; they have been handled
347 * by the above block already */
349 it
->bs
= bdrv_next_monitor_owned(it
->bs
);
351 } while (bs
&& bdrv_has_blk(bs
));
356 BlockDriverState
*bdrv_first(BdrvNextIterator
*it
)
358 *it
= (BdrvNextIterator
) {
359 .phase
= BDRV_NEXT_BACKEND_ROOTS
,
362 return bdrv_next(it
);
366 * Add a BlockBackend into the list of backends referenced by the monitor, with
367 * the given @name acting as the handle for the monitor.
368 * Strictly for use by blockdev.c.
370 * @name must not be null or empty.
372 * Returns true on success and false on failure. In the latter case, an Error
373 * object is returned through @errp.
375 bool monitor_add_blk(BlockBackend
*blk
, const char *name
, Error
**errp
)
378 assert(name
&& name
[0]);
380 if (!id_wellformed(name
)) {
381 error_setg(errp
, "Invalid device name");
384 if (blk_by_name(name
)) {
385 error_setg(errp
, "Device with id '%s' already exists", name
);
388 if (bdrv_find_node(name
)) {
390 "Device name '%s' conflicts with an existing node name",
395 blk
->name
= g_strdup(name
);
396 QTAILQ_INSERT_TAIL(&monitor_block_backends
, blk
, monitor_link
);
401 * Remove a BlockBackend from the list of backends referenced by the monitor.
402 * Strictly for use by blockdev.c.
404 void monitor_remove_blk(BlockBackend
*blk
)
410 QTAILQ_REMOVE(&monitor_block_backends
, blk
, monitor_link
);
416 * Return @blk's name, a non-null string.
417 * Returns an empty string iff @blk is not referenced by the monitor.
419 const char *blk_name(BlockBackend
*blk
)
421 return blk
->name
?: "";
425 * Return the BlockBackend with name @name if it exists, else null.
426 * @name must not be null.
428 BlockBackend
*blk_by_name(const char *name
)
430 BlockBackend
*blk
= NULL
;
433 while ((blk
= blk_next(blk
)) != NULL
) {
434 if (!strcmp(name
, blk
->name
)) {
442 * Return the BlockDriverState attached to @blk if any, else null.
444 BlockDriverState
*blk_bs(BlockBackend
*blk
)
446 return blk
->root
? blk
->root
->bs
: NULL
;
449 static BlockBackend
*bdrv_first_blk(BlockDriverState
*bs
)
452 QLIST_FOREACH(child
, &bs
->parents
, next_parent
) {
453 if (child
->role
== &child_root
) {
454 return child
->opaque
;
462 * Returns true if @bs has an associated BlockBackend.
464 bool bdrv_has_blk(BlockDriverState
*bs
)
466 return bdrv_first_blk(bs
) != NULL
;
470 * Returns true if @bs has only BlockBackends as parents.
472 bool bdrv_is_root_node(BlockDriverState
*bs
)
476 QLIST_FOREACH(c
, &bs
->parents
, next_parent
) {
477 if (c
->role
!= &child_root
) {
486 * Return @blk's DriveInfo if any, else null.
488 DriveInfo
*blk_legacy_dinfo(BlockBackend
*blk
)
490 return blk
->legacy_dinfo
;
494 * Set @blk's DriveInfo to @dinfo, and return it.
495 * @blk must not have a DriveInfo set already.
496 * No other BlockBackend may have the same DriveInfo set.
498 DriveInfo
*blk_set_legacy_dinfo(BlockBackend
*blk
, DriveInfo
*dinfo
)
500 assert(!blk
->legacy_dinfo
);
501 return blk
->legacy_dinfo
= dinfo
;
505 * Return the BlockBackend with DriveInfo @dinfo.
508 BlockBackend
*blk_by_legacy_dinfo(DriveInfo
*dinfo
)
510 BlockBackend
*blk
= NULL
;
512 while ((blk
= blk_next(blk
)) != NULL
) {
513 if (blk
->legacy_dinfo
== dinfo
) {
521 * Returns a pointer to the publicly accessible fields of @blk.
523 BlockBackendPublic
*blk_get_public(BlockBackend
*blk
)
529 * Returns a BlockBackend given the associated @public fields.
531 BlockBackend
*blk_by_public(BlockBackendPublic
*public)
533 return container_of(public, BlockBackend
, public);
537 * Disassociates the currently associated BlockDriverState from @blk.
539 void blk_remove_bs(BlockBackend
*blk
)
541 notifier_list_notify(&blk
->remove_bs_notifiers
, blk
);
542 if (blk
->public.throttle_state
) {
543 throttle_timers_detach_aio_context(&blk
->public.throttle_timers
);
546 blk_update_root_state(blk
);
548 bdrv_root_unref_child(blk
->root
);
553 * Associates a new BlockDriverState with @blk.
555 int blk_insert_bs(BlockBackend
*blk
, BlockDriverState
*bs
, Error
**errp
)
557 blk
->root
= bdrv_root_attach_child(bs
, "root", &child_root
,
558 blk
->perm
, blk
->shared_perm
, blk
, errp
);
559 if (blk
->root
== NULL
) {
564 notifier_list_notify(&blk
->insert_bs_notifiers
, blk
);
565 if (blk
->public.throttle_state
) {
566 throttle_timers_attach_aio_context(
567 &blk
->public.throttle_timers
, bdrv_get_aio_context(bs
));
574 * Sets the permission bitmasks that the user of the BlockBackend needs.
576 int blk_set_perm(BlockBackend
*blk
, uint64_t perm
, uint64_t shared_perm
,
582 ret
= bdrv_child_try_set_perm(blk
->root
, perm
, shared_perm
, errp
);
589 blk
->shared_perm
= shared_perm
;
594 void blk_get_perm(BlockBackend
*blk
, uint64_t *perm
, uint64_t *shared_perm
)
597 *shared_perm
= blk
->shared_perm
;
600 static int blk_do_attach_dev(BlockBackend
*blk
, void *dev
)
607 blk
->legacy_dev
= false;
608 blk_iostatus_reset(blk
);
613 * Attach device model @dev to @blk.
614 * Return 0 on success, -EBUSY when a device model is attached already.
616 int blk_attach_dev(BlockBackend
*blk
, DeviceState
*dev
)
618 return blk_do_attach_dev(blk
, dev
);
622 * Attach device model @dev to @blk.
623 * @blk must not have a device model attached already.
624 * TODO qdevified devices don't use this, remove when devices are qdevified
626 void blk_attach_dev_legacy(BlockBackend
*blk
, void *dev
)
628 if (blk_do_attach_dev(blk
, dev
) < 0) {
631 blk
->legacy_dev
= true;
635 * Detach device model @dev from @blk.
636 * @dev must be currently attached to @blk.
638 void blk_detach_dev(BlockBackend
*blk
, void *dev
)
639 /* TODO change to DeviceState *dev when all users are qdevified */
641 assert(blk
->dev
== dev
);
644 blk
->dev_opaque
= NULL
;
645 blk
->guest_block_size
= 512;
646 blk_set_perm(blk
, 0, BLK_PERM_ALL
, &error_abort
);
651 * Return the device model attached to @blk if any, else null.
653 void *blk_get_attached_dev(BlockBackend
*blk
)
654 /* TODO change to return DeviceState * when all users are qdevified */
659 /* Return the qdev ID, or if no ID is assigned the QOM path, of the block
660 * device attached to the BlockBackend. */
661 static char *blk_get_attached_dev_id(BlockBackend
*blk
)
665 assert(!blk
->legacy_dev
);
670 } else if (dev
->id
) {
671 return g_strdup(dev
->id
);
673 return object_get_canonical_path(OBJECT(dev
));
677 * Return the BlockBackend which has the device model @dev attached if it
680 * @dev must not be null.
682 BlockBackend
*blk_by_dev(void *dev
)
684 BlockBackend
*blk
= NULL
;
687 while ((blk
= blk_all_next(blk
)) != NULL
) {
688 if (blk
->dev
== dev
) {
696 * Set @blk's device model callbacks to @ops.
697 * @opaque is the opaque argument to pass to the callbacks.
698 * This is for use by device models.
700 void blk_set_dev_ops(BlockBackend
*blk
, const BlockDevOps
*ops
,
703 /* All drivers that use blk_set_dev_ops() are qdevified and we want to keep
704 * it that way, so we can assume blk->dev, if present, is a DeviceState if
705 * blk->dev_ops is set. Non-device users may use dev_ops without device. */
706 assert(!blk
->legacy_dev
);
709 blk
->dev_opaque
= opaque
;
711 /* Are we currently quiesced? Should we enforce this right now? */
712 if (blk
->quiesce_counter
&& ops
->drained_begin
) {
713 ops
->drained_begin(opaque
);
718 * Notify @blk's attached device model of media change.
720 * If @load is true, notify of media load. This action can fail, meaning that
721 * the medium cannot be loaded. @errp is set then.
723 * If @load is false, notify of media eject. This can never fail.
725 * Also send DEVICE_TRAY_MOVED events as appropriate.
727 void blk_dev_change_media_cb(BlockBackend
*blk
, bool load
, Error
**errp
)
729 if (blk
->dev_ops
&& blk
->dev_ops
->change_media_cb
) {
730 bool tray_was_open
, tray_is_open
;
731 Error
*local_err
= NULL
;
733 assert(!blk
->legacy_dev
);
735 tray_was_open
= blk_dev_is_tray_open(blk
);
736 blk
->dev_ops
->change_media_cb(blk
->dev_opaque
, load
, &local_err
);
738 assert(load
== true);
739 error_propagate(errp
, local_err
);
742 tray_is_open
= blk_dev_is_tray_open(blk
);
744 if (tray_was_open
!= tray_is_open
) {
745 char *id
= blk_get_attached_dev_id(blk
);
746 qapi_event_send_device_tray_moved(blk_name(blk
), id
, tray_is_open
,
753 static void blk_root_change_media(BdrvChild
*child
, bool load
)
755 blk_dev_change_media_cb(child
->opaque
, load
, NULL
);
759 * Does @blk's attached device model have removable media?
760 * %true if no device model is attached.
762 bool blk_dev_has_removable_media(BlockBackend
*blk
)
764 return !blk
->dev
|| (blk
->dev_ops
&& blk
->dev_ops
->change_media_cb
);
768 * Does @blk's attached device model have a tray?
770 bool blk_dev_has_tray(BlockBackend
*blk
)
772 return blk
->dev_ops
&& blk
->dev_ops
->is_tray_open
;
776 * Notify @blk's attached device model of a media eject request.
777 * If @force is true, the medium is about to be yanked out forcefully.
779 void blk_dev_eject_request(BlockBackend
*blk
, bool force
)
781 if (blk
->dev_ops
&& blk
->dev_ops
->eject_request_cb
) {
782 blk
->dev_ops
->eject_request_cb(blk
->dev_opaque
, force
);
787 * Does @blk's attached device model have a tray, and is it open?
789 bool blk_dev_is_tray_open(BlockBackend
*blk
)
791 if (blk_dev_has_tray(blk
)) {
792 return blk
->dev_ops
->is_tray_open(blk
->dev_opaque
);
798 * Does @blk's attached device model have the medium locked?
799 * %false if the device model has no such lock.
801 bool blk_dev_is_medium_locked(BlockBackend
*blk
)
803 if (blk
->dev_ops
&& blk
->dev_ops
->is_medium_locked
) {
804 return blk
->dev_ops
->is_medium_locked(blk
->dev_opaque
);
810 * Notify @blk's attached device model of a backend size change.
812 static void blk_root_resize(BdrvChild
*child
)
814 BlockBackend
*blk
= child
->opaque
;
816 if (blk
->dev_ops
&& blk
->dev_ops
->resize_cb
) {
817 blk
->dev_ops
->resize_cb(blk
->dev_opaque
);
821 void blk_iostatus_enable(BlockBackend
*blk
)
823 blk
->iostatus_enabled
= true;
824 blk
->iostatus
= BLOCK_DEVICE_IO_STATUS_OK
;
827 /* The I/O status is only enabled if the drive explicitly
828 * enables it _and_ the VM is configured to stop on errors */
829 bool blk_iostatus_is_enabled(const BlockBackend
*blk
)
831 return (blk
->iostatus_enabled
&&
832 (blk
->on_write_error
== BLOCKDEV_ON_ERROR_ENOSPC
||
833 blk
->on_write_error
== BLOCKDEV_ON_ERROR_STOP
||
834 blk
->on_read_error
== BLOCKDEV_ON_ERROR_STOP
));
837 BlockDeviceIoStatus
blk_iostatus(const BlockBackend
*blk
)
839 return blk
->iostatus
;
842 void blk_iostatus_disable(BlockBackend
*blk
)
844 blk
->iostatus_enabled
= false;
847 void blk_iostatus_reset(BlockBackend
*blk
)
849 if (blk_iostatus_is_enabled(blk
)) {
850 BlockDriverState
*bs
= blk_bs(blk
);
851 blk
->iostatus
= BLOCK_DEVICE_IO_STATUS_OK
;
853 block_job_iostatus_reset(bs
->job
);
858 void blk_iostatus_set_err(BlockBackend
*blk
, int error
)
860 assert(blk_iostatus_is_enabled(blk
));
861 if (blk
->iostatus
== BLOCK_DEVICE_IO_STATUS_OK
) {
862 blk
->iostatus
= error
== ENOSPC
? BLOCK_DEVICE_IO_STATUS_NOSPACE
:
863 BLOCK_DEVICE_IO_STATUS_FAILED
;
867 void blk_set_allow_write_beyond_eof(BlockBackend
*blk
, bool allow
)
869 blk
->allow_write_beyond_eof
= allow
;
872 static int blk_check_byte_request(BlockBackend
*blk
, int64_t offset
,
877 if (size
> INT_MAX
) {
881 if (!blk_is_available(blk
)) {
889 if (!blk
->allow_write_beyond_eof
) {
890 len
= blk_getlength(blk
);
895 if (offset
> len
|| len
- offset
< size
) {
903 int coroutine_fn
blk_co_preadv(BlockBackend
*blk
, int64_t offset
,
904 unsigned int bytes
, QEMUIOVector
*qiov
,
905 BdrvRequestFlags flags
)
908 BlockDriverState
*bs
= blk_bs(blk
);
910 trace_blk_co_preadv(blk
, bs
, offset
, bytes
, flags
);
912 ret
= blk_check_byte_request(blk
, offset
, bytes
);
917 bdrv_inc_in_flight(bs
);
919 /* throttling disk I/O */
920 if (blk
->public.throttle_state
) {
921 throttle_group_co_io_limits_intercept(blk
, bytes
, false);
924 ret
= bdrv_co_preadv(blk
->root
, offset
, bytes
, qiov
, flags
);
925 bdrv_dec_in_flight(bs
);
929 int coroutine_fn
blk_co_pwritev(BlockBackend
*blk
, int64_t offset
,
930 unsigned int bytes
, QEMUIOVector
*qiov
,
931 BdrvRequestFlags flags
)
934 BlockDriverState
*bs
= blk_bs(blk
);
936 trace_blk_co_pwritev(blk
, bs
, offset
, bytes
, flags
);
938 ret
= blk_check_byte_request(blk
, offset
, bytes
);
943 bdrv_inc_in_flight(bs
);
945 /* throttling disk I/O */
946 if (blk
->public.throttle_state
) {
947 throttle_group_co_io_limits_intercept(blk
, bytes
, true);
950 if (!blk
->enable_write_cache
) {
951 flags
|= BDRV_REQ_FUA
;
954 ret
= bdrv_co_pwritev(blk
->root
, offset
, bytes
, qiov
, flags
);
955 bdrv_dec_in_flight(bs
);
959 typedef struct BlkRwCo
{
964 BdrvRequestFlags flags
;
967 static void blk_read_entry(void *opaque
)
969 BlkRwCo
*rwco
= opaque
;
971 rwco
->ret
= blk_co_preadv(rwco
->blk
, rwco
->offset
, rwco
->qiov
->size
,
972 rwco
->qiov
, rwco
->flags
);
975 static void blk_write_entry(void *opaque
)
977 BlkRwCo
*rwco
= opaque
;
979 rwco
->ret
= blk_co_pwritev(rwco
->blk
, rwco
->offset
, rwco
->qiov
->size
,
980 rwco
->qiov
, rwco
->flags
);
983 static int blk_prw(BlockBackend
*blk
, int64_t offset
, uint8_t *buf
,
984 int64_t bytes
, CoroutineEntry co_entry
,
985 BdrvRequestFlags flags
)
991 iov
= (struct iovec
) {
995 qemu_iovec_init_external(&qiov
, &iov
, 1);
1005 if (qemu_in_coroutine()) {
1006 /* Fast-path if already in coroutine context */
1009 Coroutine
*co
= qemu_coroutine_create(co_entry
, &rwco
);
1010 qemu_coroutine_enter(co
);
1011 BDRV_POLL_WHILE(blk_bs(blk
), rwco
.ret
== NOT_DONE
);
1017 int blk_pread_unthrottled(BlockBackend
*blk
, int64_t offset
, uint8_t *buf
,
1022 ret
= blk_check_byte_request(blk
, offset
, count
);
1027 blk_root_drained_begin(blk
->root
);
1028 ret
= blk_pread(blk
, offset
, buf
, count
);
1029 blk_root_drained_end(blk
->root
);
1033 int blk_pwrite_zeroes(BlockBackend
*blk
, int64_t offset
,
1034 int count
, BdrvRequestFlags flags
)
1036 return blk_prw(blk
, offset
, NULL
, count
, blk_write_entry
,
1037 flags
| BDRV_REQ_ZERO_WRITE
);
1040 int blk_make_zero(BlockBackend
*blk
, BdrvRequestFlags flags
)
1042 return bdrv_make_zero(blk
->root
, flags
);
1045 static void error_callback_bh(void *opaque
)
1047 struct BlockBackendAIOCB
*acb
= opaque
;
1049 bdrv_dec_in_flight(acb
->common
.bs
);
1050 acb
->common
.cb(acb
->common
.opaque
, acb
->ret
);
1051 qemu_aio_unref(acb
);
1054 BlockAIOCB
*blk_abort_aio_request(BlockBackend
*blk
,
1055 BlockCompletionFunc
*cb
,
1056 void *opaque
, int ret
)
1058 struct BlockBackendAIOCB
*acb
;
1060 bdrv_inc_in_flight(blk_bs(blk
));
1061 acb
= blk_aio_get(&block_backend_aiocb_info
, blk
, cb
, opaque
);
1065 aio_bh_schedule_oneshot(blk_get_aio_context(blk
), error_callback_bh
, acb
);
1066 return &acb
->common
;
1069 typedef struct BlkAioEmAIOCB
{
1076 static const AIOCBInfo blk_aio_em_aiocb_info
= {
1077 .aiocb_size
= sizeof(BlkAioEmAIOCB
),
1080 static void blk_aio_complete(BlkAioEmAIOCB
*acb
)
1082 if (acb
->has_returned
) {
1083 bdrv_dec_in_flight(acb
->common
.bs
);
1084 acb
->common
.cb(acb
->common
.opaque
, acb
->rwco
.ret
);
1085 qemu_aio_unref(acb
);
1089 static void blk_aio_complete_bh(void *opaque
)
1091 BlkAioEmAIOCB
*acb
= opaque
;
1092 assert(acb
->has_returned
);
1093 blk_aio_complete(acb
);
1096 static BlockAIOCB
*blk_aio_prwv(BlockBackend
*blk
, int64_t offset
, int bytes
,
1097 QEMUIOVector
*qiov
, CoroutineEntry co_entry
,
1098 BdrvRequestFlags flags
,
1099 BlockCompletionFunc
*cb
, void *opaque
)
1104 bdrv_inc_in_flight(blk_bs(blk
));
1105 acb
= blk_aio_get(&blk_aio_em_aiocb_info
, blk
, cb
, opaque
);
1106 acb
->rwco
= (BlkRwCo
) {
1114 acb
->has_returned
= false;
1116 co
= qemu_coroutine_create(co_entry
, acb
);
1117 qemu_coroutine_enter(co
);
1119 acb
->has_returned
= true;
1120 if (acb
->rwco
.ret
!= NOT_DONE
) {
1121 aio_bh_schedule_oneshot(blk_get_aio_context(blk
),
1122 blk_aio_complete_bh
, acb
);
1125 return &acb
->common
;
1128 static void blk_aio_read_entry(void *opaque
)
1130 BlkAioEmAIOCB
*acb
= opaque
;
1131 BlkRwCo
*rwco
= &acb
->rwco
;
1133 assert(rwco
->qiov
->size
== acb
->bytes
);
1134 rwco
->ret
= blk_co_preadv(rwco
->blk
, rwco
->offset
, acb
->bytes
,
1135 rwco
->qiov
, rwco
->flags
);
1136 blk_aio_complete(acb
);
1139 static void blk_aio_write_entry(void *opaque
)
1141 BlkAioEmAIOCB
*acb
= opaque
;
1142 BlkRwCo
*rwco
= &acb
->rwco
;
1144 assert(!rwco
->qiov
|| rwco
->qiov
->size
== acb
->bytes
);
1145 rwco
->ret
= blk_co_pwritev(rwco
->blk
, rwco
->offset
, acb
->bytes
,
1146 rwco
->qiov
, rwco
->flags
);
1147 blk_aio_complete(acb
);
1150 BlockAIOCB
*blk_aio_pwrite_zeroes(BlockBackend
*blk
, int64_t offset
,
1151 int count
, BdrvRequestFlags flags
,
1152 BlockCompletionFunc
*cb
, void *opaque
)
1154 return blk_aio_prwv(blk
, offset
, count
, NULL
, blk_aio_write_entry
,
1155 flags
| BDRV_REQ_ZERO_WRITE
, cb
, opaque
);
1158 int blk_pread(BlockBackend
*blk
, int64_t offset
, void *buf
, int count
)
1160 int ret
= blk_prw(blk
, offset
, buf
, count
, blk_read_entry
, 0);
1167 int blk_pwrite(BlockBackend
*blk
, int64_t offset
, const void *buf
, int count
,
1168 BdrvRequestFlags flags
)
1170 int ret
= blk_prw(blk
, offset
, (void *) buf
, count
, blk_write_entry
,
1178 int64_t blk_getlength(BlockBackend
*blk
)
1180 if (!blk_is_available(blk
)) {
1184 return bdrv_getlength(blk_bs(blk
));
1187 void blk_get_geometry(BlockBackend
*blk
, uint64_t *nb_sectors_ptr
)
1190 *nb_sectors_ptr
= 0;
1192 bdrv_get_geometry(blk_bs(blk
), nb_sectors_ptr
);
1196 int64_t blk_nb_sectors(BlockBackend
*blk
)
1198 if (!blk_is_available(blk
)) {
1202 return bdrv_nb_sectors(blk_bs(blk
));
1205 BlockAIOCB
*blk_aio_preadv(BlockBackend
*blk
, int64_t offset
,
1206 QEMUIOVector
*qiov
, BdrvRequestFlags flags
,
1207 BlockCompletionFunc
*cb
, void *opaque
)
1209 return blk_aio_prwv(blk
, offset
, qiov
->size
, qiov
,
1210 blk_aio_read_entry
, flags
, cb
, opaque
);
1213 BlockAIOCB
*blk_aio_pwritev(BlockBackend
*blk
, int64_t offset
,
1214 QEMUIOVector
*qiov
, BdrvRequestFlags flags
,
1215 BlockCompletionFunc
*cb
, void *opaque
)
1217 return blk_aio_prwv(blk
, offset
, qiov
->size
, qiov
,
1218 blk_aio_write_entry
, flags
, cb
, opaque
);
1221 static void blk_aio_flush_entry(void *opaque
)
1223 BlkAioEmAIOCB
*acb
= opaque
;
1224 BlkRwCo
*rwco
= &acb
->rwco
;
1226 rwco
->ret
= blk_co_flush(rwco
->blk
);
1227 blk_aio_complete(acb
);
1230 BlockAIOCB
*blk_aio_flush(BlockBackend
*blk
,
1231 BlockCompletionFunc
*cb
, void *opaque
)
1233 return blk_aio_prwv(blk
, 0, 0, NULL
, blk_aio_flush_entry
, 0, cb
, opaque
);
1236 static void blk_aio_pdiscard_entry(void *opaque
)
1238 BlkAioEmAIOCB
*acb
= opaque
;
1239 BlkRwCo
*rwco
= &acb
->rwco
;
1241 rwco
->ret
= blk_co_pdiscard(rwco
->blk
, rwco
->offset
, acb
->bytes
);
1242 blk_aio_complete(acb
);
1245 BlockAIOCB
*blk_aio_pdiscard(BlockBackend
*blk
,
1246 int64_t offset
, int count
,
1247 BlockCompletionFunc
*cb
, void *opaque
)
1249 return blk_aio_prwv(blk
, offset
, count
, NULL
, blk_aio_pdiscard_entry
, 0,
1253 void blk_aio_cancel(BlockAIOCB
*acb
)
1255 bdrv_aio_cancel(acb
);
1258 void blk_aio_cancel_async(BlockAIOCB
*acb
)
1260 bdrv_aio_cancel_async(acb
);
1263 int blk_co_ioctl(BlockBackend
*blk
, unsigned long int req
, void *buf
)
1265 if (!blk_is_available(blk
)) {
1269 return bdrv_co_ioctl(blk_bs(blk
), req
, buf
);
1272 static void blk_ioctl_entry(void *opaque
)
1274 BlkRwCo
*rwco
= opaque
;
1275 rwco
->ret
= blk_co_ioctl(rwco
->blk
, rwco
->offset
,
1276 rwco
->qiov
->iov
[0].iov_base
);
1279 int blk_ioctl(BlockBackend
*blk
, unsigned long int req
, void *buf
)
1281 return blk_prw(blk
, req
, buf
, 0, blk_ioctl_entry
, 0);
1284 static void blk_aio_ioctl_entry(void *opaque
)
1286 BlkAioEmAIOCB
*acb
= opaque
;
1287 BlkRwCo
*rwco
= &acb
->rwco
;
1289 rwco
->ret
= blk_co_ioctl(rwco
->blk
, rwco
->offset
,
1290 rwco
->qiov
->iov
[0].iov_base
);
1291 blk_aio_complete(acb
);
1294 BlockAIOCB
*blk_aio_ioctl(BlockBackend
*blk
, unsigned long int req
, void *buf
,
1295 BlockCompletionFunc
*cb
, void *opaque
)
1300 iov
= (struct iovec
) {
1304 qemu_iovec_init_external(&qiov
, &iov
, 1);
1306 return blk_aio_prwv(blk
, req
, 0, &qiov
, blk_aio_ioctl_entry
, 0, cb
, opaque
);
1309 int blk_co_pdiscard(BlockBackend
*blk
, int64_t offset
, int count
)
1311 int ret
= blk_check_byte_request(blk
, offset
, count
);
1316 return bdrv_co_pdiscard(blk_bs(blk
), offset
, count
);
1319 int blk_co_flush(BlockBackend
*blk
)
1321 if (!blk_is_available(blk
)) {
1325 return bdrv_co_flush(blk_bs(blk
));
1328 static void blk_flush_entry(void *opaque
)
1330 BlkRwCo
*rwco
= opaque
;
1331 rwco
->ret
= blk_co_flush(rwco
->blk
);
1334 int blk_flush(BlockBackend
*blk
)
1336 return blk_prw(blk
, 0, NULL
, 0, blk_flush_entry
, 0);
1339 void blk_drain(BlockBackend
*blk
)
1342 bdrv_drain(blk_bs(blk
));
1346 void blk_drain_all(void)
1351 void blk_set_on_error(BlockBackend
*blk
, BlockdevOnError on_read_error
,
1352 BlockdevOnError on_write_error
)
1354 blk
->on_read_error
= on_read_error
;
1355 blk
->on_write_error
= on_write_error
;
1358 BlockdevOnError
blk_get_on_error(BlockBackend
*blk
, bool is_read
)
1360 return is_read
? blk
->on_read_error
: blk
->on_write_error
;
1363 BlockErrorAction
blk_get_error_action(BlockBackend
*blk
, bool is_read
,
1366 BlockdevOnError on_err
= blk_get_on_error(blk
, is_read
);
1369 case BLOCKDEV_ON_ERROR_ENOSPC
:
1370 return (error
== ENOSPC
) ?
1371 BLOCK_ERROR_ACTION_STOP
: BLOCK_ERROR_ACTION_REPORT
;
1372 case BLOCKDEV_ON_ERROR_STOP
:
1373 return BLOCK_ERROR_ACTION_STOP
;
1374 case BLOCKDEV_ON_ERROR_REPORT
:
1375 return BLOCK_ERROR_ACTION_REPORT
;
1376 case BLOCKDEV_ON_ERROR_IGNORE
:
1377 return BLOCK_ERROR_ACTION_IGNORE
;
1378 case BLOCKDEV_ON_ERROR_AUTO
:
1384 static void send_qmp_error_event(BlockBackend
*blk
,
1385 BlockErrorAction action
,
1386 bool is_read
, int error
)
1388 IoOperationType optype
;
1390 optype
= is_read
? IO_OPERATION_TYPE_READ
: IO_OPERATION_TYPE_WRITE
;
1391 qapi_event_send_block_io_error(blk_name(blk
),
1392 bdrv_get_node_name(blk_bs(blk
)), optype
,
1393 action
, blk_iostatus_is_enabled(blk
),
1394 error
== ENOSPC
, strerror(error
),
1398 /* This is done by device models because, while the block layer knows
1399 * about the error, it does not know whether an operation comes from
1400 * the device or the block layer (from a job, for example).
1402 void blk_error_action(BlockBackend
*blk
, BlockErrorAction action
,
1403 bool is_read
, int error
)
1407 if (action
== BLOCK_ERROR_ACTION_STOP
) {
1408 /* First set the iostatus, so that "info block" returns an iostatus
1409 * that matches the events raised so far (an additional error iostatus
1410 * is fine, but not a lost one).
1412 blk_iostatus_set_err(blk
, error
);
1414 /* Then raise the request to stop the VM and the event.
1415 * qemu_system_vmstop_request_prepare has two effects. First,
1416 * it ensures that the STOP event always comes after the
1417 * BLOCK_IO_ERROR event. Second, it ensures that even if management
1418 * can observe the STOP event and do a "cont" before the STOP
1419 * event is issued, the VM will not stop. In this case, vm_start()
1420 * also ensures that the STOP/RESUME pair of events is emitted.
1422 qemu_system_vmstop_request_prepare();
1423 send_qmp_error_event(blk
, action
, is_read
, error
);
1424 qemu_system_vmstop_request(RUN_STATE_IO_ERROR
);
1426 send_qmp_error_event(blk
, action
, is_read
, error
);
1430 int blk_is_read_only(BlockBackend
*blk
)
1432 BlockDriverState
*bs
= blk_bs(blk
);
1435 return bdrv_is_read_only(bs
);
1437 return blk
->root_state
.read_only
;
1441 int blk_is_sg(BlockBackend
*blk
)
1443 BlockDriverState
*bs
= blk_bs(blk
);
1449 return bdrv_is_sg(bs
);
1452 int blk_enable_write_cache(BlockBackend
*blk
)
1454 return blk
->enable_write_cache
;
1457 void blk_set_enable_write_cache(BlockBackend
*blk
, bool wce
)
1459 blk
->enable_write_cache
= wce
;
1462 void blk_invalidate_cache(BlockBackend
*blk
, Error
**errp
)
1464 BlockDriverState
*bs
= blk_bs(blk
);
1467 error_setg(errp
, "Device '%s' has no medium", blk
->name
);
1471 bdrv_invalidate_cache(bs
, errp
);
1474 bool blk_is_inserted(BlockBackend
*blk
)
1476 BlockDriverState
*bs
= blk_bs(blk
);
1478 return bs
&& bdrv_is_inserted(bs
);
1481 bool blk_is_available(BlockBackend
*blk
)
1483 return blk_is_inserted(blk
) && !blk_dev_is_tray_open(blk
);
1486 void blk_lock_medium(BlockBackend
*blk
, bool locked
)
1488 BlockDriverState
*bs
= blk_bs(blk
);
1491 bdrv_lock_medium(bs
, locked
);
1495 void blk_eject(BlockBackend
*blk
, bool eject_flag
)
1497 BlockDriverState
*bs
= blk_bs(blk
);
1500 /* blk_eject is only called by qdevified devices */
1501 assert(!blk
->legacy_dev
);
1504 bdrv_eject(bs
, eject_flag
);
1507 /* Whether or not we ejected on the backend,
1508 * the frontend experienced a tray event. */
1509 id
= blk_get_attached_dev_id(blk
);
1510 qapi_event_send_device_tray_moved(blk_name(blk
), id
,
1511 eject_flag
, &error_abort
);
1515 int blk_get_flags(BlockBackend
*blk
)
1517 BlockDriverState
*bs
= blk_bs(blk
);
1520 return bdrv_get_flags(bs
);
1522 return blk
->root_state
.open_flags
;
1526 /* Returns the maximum transfer length, in bytes; guaranteed nonzero */
1527 uint32_t blk_get_max_transfer(BlockBackend
*blk
)
1529 BlockDriverState
*bs
= blk_bs(blk
);
1533 max
= bs
->bl
.max_transfer
;
1535 return MIN_NON_ZERO(max
, INT_MAX
);
1538 int blk_get_max_iov(BlockBackend
*blk
)
1540 return blk
->root
->bs
->bl
.max_iov
;
1543 void blk_set_guest_block_size(BlockBackend
*blk
, int align
)
1545 blk
->guest_block_size
= align
;
1548 void *blk_try_blockalign(BlockBackend
*blk
, size_t size
)
1550 return qemu_try_blockalign(blk
? blk_bs(blk
) : NULL
, size
);
1553 void *blk_blockalign(BlockBackend
*blk
, size_t size
)
1555 return qemu_blockalign(blk
? blk_bs(blk
) : NULL
, size
);
1558 bool blk_op_is_blocked(BlockBackend
*blk
, BlockOpType op
, Error
**errp
)
1560 BlockDriverState
*bs
= blk_bs(blk
);
1566 return bdrv_op_is_blocked(bs
, op
, errp
);
1569 void blk_op_unblock(BlockBackend
*blk
, BlockOpType op
, Error
*reason
)
1571 BlockDriverState
*bs
= blk_bs(blk
);
1574 bdrv_op_unblock(bs
, op
, reason
);
1578 void blk_op_block_all(BlockBackend
*blk
, Error
*reason
)
1580 BlockDriverState
*bs
= blk_bs(blk
);
1583 bdrv_op_block_all(bs
, reason
);
1587 void blk_op_unblock_all(BlockBackend
*blk
, Error
*reason
)
1589 BlockDriverState
*bs
= blk_bs(blk
);
1592 bdrv_op_unblock_all(bs
, reason
);
1596 AioContext
*blk_get_aio_context(BlockBackend
*blk
)
1598 BlockDriverState
*bs
= blk_bs(blk
);
1601 return bdrv_get_aio_context(bs
);
1603 return qemu_get_aio_context();
1607 static AioContext
*blk_aiocb_get_aio_context(BlockAIOCB
*acb
)
1609 BlockBackendAIOCB
*blk_acb
= DO_UPCAST(BlockBackendAIOCB
, common
, acb
);
1610 return blk_get_aio_context(blk_acb
->blk
);
1613 void blk_set_aio_context(BlockBackend
*blk
, AioContext
*new_context
)
1615 BlockDriverState
*bs
= blk_bs(blk
);
1618 if (blk
->public.throttle_state
) {
1619 throttle_timers_detach_aio_context(&blk
->public.throttle_timers
);
1621 bdrv_set_aio_context(bs
, new_context
);
1622 if (blk
->public.throttle_state
) {
1623 throttle_timers_attach_aio_context(&blk
->public.throttle_timers
,
1629 void blk_add_aio_context_notifier(BlockBackend
*blk
,
1630 void (*attached_aio_context
)(AioContext
*new_context
, void *opaque
),
1631 void (*detach_aio_context
)(void *opaque
), void *opaque
)
1633 BlockDriverState
*bs
= blk_bs(blk
);
1636 bdrv_add_aio_context_notifier(bs
, attached_aio_context
,
1637 detach_aio_context
, opaque
);
1641 void blk_remove_aio_context_notifier(BlockBackend
*blk
,
1642 void (*attached_aio_context
)(AioContext
*,
1644 void (*detach_aio_context
)(void *),
1647 BlockDriverState
*bs
= blk_bs(blk
);
1650 bdrv_remove_aio_context_notifier(bs
, attached_aio_context
,
1651 detach_aio_context
, opaque
);
1655 void blk_add_remove_bs_notifier(BlockBackend
*blk
, Notifier
*notify
)
1657 notifier_list_add(&blk
->remove_bs_notifiers
, notify
);
1660 void blk_add_insert_bs_notifier(BlockBackend
*blk
, Notifier
*notify
)
1662 notifier_list_add(&blk
->insert_bs_notifiers
, notify
);
1665 void blk_io_plug(BlockBackend
*blk
)
1667 BlockDriverState
*bs
= blk_bs(blk
);
1674 void blk_io_unplug(BlockBackend
*blk
)
1676 BlockDriverState
*bs
= blk_bs(blk
);
1683 BlockAcctStats
*blk_get_stats(BlockBackend
*blk
)
1688 void *blk_aio_get(const AIOCBInfo
*aiocb_info
, BlockBackend
*blk
,
1689 BlockCompletionFunc
*cb
, void *opaque
)
1691 return qemu_aio_get(aiocb_info
, blk_bs(blk
), cb
, opaque
);
1694 int coroutine_fn
blk_co_pwrite_zeroes(BlockBackend
*blk
, int64_t offset
,
1695 int count
, BdrvRequestFlags flags
)
1697 return blk_co_pwritev(blk
, offset
, count
, NULL
,
1698 flags
| BDRV_REQ_ZERO_WRITE
);
1701 int blk_pwrite_compressed(BlockBackend
*blk
, int64_t offset
, const void *buf
,
1704 return blk_prw(blk
, offset
, (void *) buf
, count
, blk_write_entry
,
1705 BDRV_REQ_WRITE_COMPRESSED
);
1708 int blk_truncate(BlockBackend
*blk
, int64_t offset
)
1710 if (!blk_is_available(blk
)) {
1714 return bdrv_truncate(blk
->root
, offset
);
1717 static void blk_pdiscard_entry(void *opaque
)
1719 BlkRwCo
*rwco
= opaque
;
1720 rwco
->ret
= blk_co_pdiscard(rwco
->blk
, rwco
->offset
, rwco
->qiov
->size
);
1723 int blk_pdiscard(BlockBackend
*blk
, int64_t offset
, int count
)
1725 return blk_prw(blk
, offset
, NULL
, count
, blk_pdiscard_entry
, 0);
1728 int blk_save_vmstate(BlockBackend
*blk
, const uint8_t *buf
,
1729 int64_t pos
, int size
)
1733 if (!blk_is_available(blk
)) {
1737 ret
= bdrv_save_vmstate(blk_bs(blk
), buf
, pos
, size
);
1742 if (ret
== size
&& !blk
->enable_write_cache
) {
1743 ret
= bdrv_flush(blk_bs(blk
));
1746 return ret
< 0 ? ret
: size
;
1749 int blk_load_vmstate(BlockBackend
*blk
, uint8_t *buf
, int64_t pos
, int size
)
1751 if (!blk_is_available(blk
)) {
1755 return bdrv_load_vmstate(blk_bs(blk
), buf
, pos
, size
);
1758 int blk_probe_blocksizes(BlockBackend
*blk
, BlockSizes
*bsz
)
1760 if (!blk_is_available(blk
)) {
1764 return bdrv_probe_blocksizes(blk_bs(blk
), bsz
);
1767 int blk_probe_geometry(BlockBackend
*blk
, HDGeometry
*geo
)
1769 if (!blk_is_available(blk
)) {
1773 return bdrv_probe_geometry(blk_bs(blk
), geo
);
1777 * Updates the BlockBackendRootState object with data from the currently
1778 * attached BlockDriverState.
1780 void blk_update_root_state(BlockBackend
*blk
)
1784 blk
->root_state
.open_flags
= blk
->root
->bs
->open_flags
;
1785 blk
->root_state
.read_only
= blk
->root
->bs
->read_only
;
1786 blk
->root_state
.detect_zeroes
= blk
->root
->bs
->detect_zeroes
;
1790 * Returns the detect-zeroes setting to be used for bdrv_open() of a
1791 * BlockDriverState which is supposed to inherit the root state.
1793 bool blk_get_detect_zeroes_from_root_state(BlockBackend
*blk
)
1795 return blk
->root_state
.detect_zeroes
;
1799 * Returns the flags to be used for bdrv_open() of a BlockDriverState which is
1800 * supposed to inherit the root state.
1802 int blk_get_open_flags_from_root_state(BlockBackend
*blk
)
1806 bs_flags
= blk
->root_state
.read_only
? 0 : BDRV_O_RDWR
;
1807 bs_flags
|= blk
->root_state
.open_flags
& ~BDRV_O_RDWR
;
1812 BlockBackendRootState
*blk_get_root_state(BlockBackend
*blk
)
1814 return &blk
->root_state
;
1817 int blk_commit_all(void)
1819 BlockBackend
*blk
= NULL
;
1821 while ((blk
= blk_all_next(blk
)) != NULL
) {
1822 AioContext
*aio_context
= blk_get_aio_context(blk
);
1824 aio_context_acquire(aio_context
);
1825 if (blk_is_inserted(blk
) && blk
->root
->bs
->backing
) {
1826 int ret
= bdrv_commit(blk
->root
->bs
);
1828 aio_context_release(aio_context
);
1832 aio_context_release(aio_context
);
1838 /* throttling disk I/O limits */
1839 void blk_set_io_limits(BlockBackend
*blk
, ThrottleConfig
*cfg
)
1841 throttle_group_config(blk
, cfg
);
1844 void blk_io_limits_disable(BlockBackend
*blk
)
1846 assert(blk
->public.throttle_state
);
1847 bdrv_drained_begin(blk_bs(blk
));
1848 throttle_group_unregister_blk(blk
);
1849 bdrv_drained_end(blk_bs(blk
));
1852 /* should be called before blk_set_io_limits if a limit is set */
1853 void blk_io_limits_enable(BlockBackend
*blk
, const char *group
)
1855 assert(!blk
->public.throttle_state
);
1856 throttle_group_register_blk(blk
, group
);
1859 void blk_io_limits_update_group(BlockBackend
*blk
, const char *group
)
1861 /* this BB is not part of any group */
1862 if (!blk
->public.throttle_state
) {
1866 /* this BB is a part of the same group than the one we want */
1867 if (!g_strcmp0(throttle_group_get_name(blk
), group
)) {
1871 /* need to change the group this bs belong to */
1872 blk_io_limits_disable(blk
);
1873 blk_io_limits_enable(blk
, group
);
1876 static void blk_root_drained_begin(BdrvChild
*child
)
1878 BlockBackend
*blk
= child
->opaque
;
1880 if (++blk
->quiesce_counter
== 1) {
1881 if (blk
->dev_ops
&& blk
->dev_ops
->drained_begin
) {
1882 blk
->dev_ops
->drained_begin(blk
->dev_opaque
);
1886 /* Note that blk->root may not be accessible here yet if we are just
1887 * attaching to a BlockDriverState that is drained. Use child instead. */
1889 if (blk
->public.io_limits_disabled
++ == 0) {
1890 throttle_group_restart_blk(blk
);
1894 static void blk_root_drained_end(BdrvChild
*child
)
1896 BlockBackend
*blk
= child
->opaque
;
1897 assert(blk
->quiesce_counter
);
1899 assert(blk
->public.io_limits_disabled
);
1900 --blk
->public.io_limits_disabled
;
1902 if (--blk
->quiesce_counter
== 0) {
1903 if (blk
->dev_ops
&& blk
->dev_ops
->drained_end
) {
1904 blk
->dev_ops
->drained_end(blk
->dev_opaque
);