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
;
70 typedef struct BlockBackendAIOCB
{
76 static const AIOCBInfo block_backend_aiocb_info
= {
77 .get_aio_context
= blk_aiocb_get_aio_context
,
78 .aiocb_size
= sizeof(BlockBackendAIOCB
),
81 static void drive_info_del(DriveInfo
*dinfo
);
82 static BlockBackend
*bdrv_first_blk(BlockDriverState
*bs
);
83 static char *blk_get_attached_dev_id(BlockBackend
*blk
);
85 /* All BlockBackends */
86 static QTAILQ_HEAD(, BlockBackend
) block_backends
=
87 QTAILQ_HEAD_INITIALIZER(block_backends
);
89 /* All BlockBackends referenced by the monitor and which are iterated through by
91 static QTAILQ_HEAD(, BlockBackend
) monitor_block_backends
=
92 QTAILQ_HEAD_INITIALIZER(monitor_block_backends
);
94 static void blk_root_inherit_options(int *child_flags
, QDict
*child_options
,
95 int parent_flags
, QDict
*parent_options
)
97 /* We're not supposed to call this function for root nodes */
100 static void blk_root_drained_begin(BdrvChild
*child
);
101 static void blk_root_drained_end(BdrvChild
*child
);
103 static void blk_root_change_media(BdrvChild
*child
, bool load
);
104 static void blk_root_resize(BdrvChild
*child
);
106 static char *blk_root_get_parent_desc(BdrvChild
*child
)
108 BlockBackend
*blk
= child
->opaque
;
112 return g_strdup(blk
->name
);
115 dev_id
= blk_get_attached_dev_id(blk
);
119 /* TODO Callback into the BB owner for something more detailed */
121 return g_strdup("a block device");
125 static const char *blk_root_get_name(BdrvChild
*child
)
127 return blk_name(child
->opaque
);
130 static const BdrvChildRole child_root
= {
131 .inherit_options
= blk_root_inherit_options
,
133 .change_media
= blk_root_change_media
,
134 .resize
= blk_root_resize
,
135 .get_name
= blk_root_get_name
,
136 .get_parent_desc
= blk_root_get_parent_desc
,
138 .drained_begin
= blk_root_drained_begin
,
139 .drained_end
= blk_root_drained_end
,
143 * Create a new BlockBackend with a reference count of one.
145 * @perm is a bitmasks of BLK_PERM_* constants which describes the permissions
146 * to request for a block driver node that is attached to this BlockBackend.
147 * @shared_perm is a bitmask which describes which permissions may be granted
148 * to other users of the attached node.
149 * Both sets of permissions can be changed later using blk_set_perm().
151 * Return the new BlockBackend on success, null on failure.
153 BlockBackend
*blk_new(uint64_t perm
, uint64_t shared_perm
)
157 blk
= g_new0(BlockBackend
, 1);
160 blk
->shared_perm
= shared_perm
;
161 blk_set_enable_write_cache(blk
, true);
163 qemu_co_queue_init(&blk
->public.throttled_reqs
[0]);
164 qemu_co_queue_init(&blk
->public.throttled_reqs
[1]);
166 notifier_list_init(&blk
->remove_bs_notifiers
);
167 notifier_list_init(&blk
->insert_bs_notifiers
);
169 QTAILQ_INSERT_TAIL(&block_backends
, blk
, link
);
174 * Creates a new BlockBackend, opens a new BlockDriverState, and connects both.
176 * Just as with bdrv_open(), after having called this function the reference to
177 * @options belongs to the block layer (even on failure).
179 * TODO: Remove @filename and @flags; it should be possible to specify a whole
180 * BDS tree just by specifying the @options QDict (or @reference,
181 * alternatively). At the time of adding this function, this is not possible,
182 * though, so callers of this function have to be able to specify @filename and
185 BlockBackend
*blk_new_open(const char *filename
, const char *reference
,
186 QDict
*options
, int flags
, Error
**errp
)
189 BlockDriverState
*bs
;
192 /* blk_new_open() is mainly used in .bdrv_create implementations and the
193 * tools where sharing isn't a concern because the BDS stays private, so we
194 * just request permission according to the flags.
196 * The exceptions are xen_disk and blockdev_init(); in these cases, the
197 * caller of blk_new_open() doesn't make use of the permissions, but they
198 * shouldn't hurt either. We can still share everything here because the
199 * guest devices will add their own blockers if they can't share. */
200 perm
= BLK_PERM_CONSISTENT_READ
;
201 if (flags
& BDRV_O_RDWR
) {
202 perm
|= BLK_PERM_WRITE
;
204 if (flags
& BDRV_O_RESIZE
) {
205 perm
|= BLK_PERM_RESIZE
;
208 blk
= blk_new(perm
, BLK_PERM_ALL
);
209 bs
= bdrv_open(filename
, reference
, options
, flags
, errp
);
215 blk
->root
= bdrv_root_attach_child(bs
, "root", &child_root
,
216 perm
, BLK_PERM_ALL
, blk
, &error_abort
);
221 static void blk_delete(BlockBackend
*blk
)
223 assert(!blk
->refcnt
);
229 assert(QLIST_EMPTY(&blk
->remove_bs_notifiers
.notifiers
));
230 assert(QLIST_EMPTY(&blk
->insert_bs_notifiers
.notifiers
));
231 QTAILQ_REMOVE(&block_backends
, blk
, link
);
232 drive_info_del(blk
->legacy_dinfo
);
233 block_acct_cleanup(&blk
->stats
);
237 static void drive_info_del(DriveInfo
*dinfo
)
242 qemu_opts_del(dinfo
->opts
);
243 g_free(dinfo
->serial
);
247 int blk_get_refcnt(BlockBackend
*blk
)
249 return blk
? blk
->refcnt
: 0;
253 * Increment @blk's reference count.
254 * @blk must not be null.
256 void blk_ref(BlockBackend
*blk
)
262 * Decrement @blk's reference count.
263 * If this drops it to zero, destroy @blk.
264 * For convenience, do nothing if @blk is null.
266 void blk_unref(BlockBackend
*blk
)
269 assert(blk
->refcnt
> 0);
270 if (!--blk
->refcnt
) {
277 * Behaves similarly to blk_next() but iterates over all BlockBackends, even the
278 * ones which are hidden (i.e. are not referenced by the monitor).
280 static BlockBackend
*blk_all_next(BlockBackend
*blk
)
282 return blk
? QTAILQ_NEXT(blk
, link
)
283 : QTAILQ_FIRST(&block_backends
);
286 void blk_remove_all_bs(void)
288 BlockBackend
*blk
= NULL
;
290 while ((blk
= blk_all_next(blk
)) != NULL
) {
291 AioContext
*ctx
= blk_get_aio_context(blk
);
293 aio_context_acquire(ctx
);
297 aio_context_release(ctx
);
302 * Return the monitor-owned BlockBackend after @blk.
303 * If @blk is null, return the first one.
304 * Else, return @blk's next sibling, which may be null.
306 * To iterate over all BlockBackends, do
307 * for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
311 BlockBackend
*blk_next(BlockBackend
*blk
)
313 return blk
? QTAILQ_NEXT(blk
, monitor_link
)
314 : QTAILQ_FIRST(&monitor_block_backends
);
317 /* Iterates over all top-level BlockDriverStates, i.e. BDSs that are owned by
318 * the monitor or attached to a BlockBackend */
319 BlockDriverState
*bdrv_next(BdrvNextIterator
*it
)
321 BlockDriverState
*bs
;
323 /* First, return all root nodes of BlockBackends. In order to avoid
324 * returning a BDS twice when multiple BBs refer to it, we only return it
325 * if the BB is the first one in the parent list of the BDS. */
326 if (it
->phase
== BDRV_NEXT_BACKEND_ROOTS
) {
328 it
->blk
= blk_all_next(it
->blk
);
329 bs
= it
->blk
? blk_bs(it
->blk
) : NULL
;
330 } while (it
->blk
&& (bs
== NULL
|| bdrv_first_blk(bs
) != it
->blk
));
335 it
->phase
= BDRV_NEXT_MONITOR_OWNED
;
338 /* Then return the monitor-owned BDSes without a BB attached. Ignore all
339 * BDSes that are attached to a BlockBackend here; they have been handled
340 * by the above block already */
342 it
->bs
= bdrv_next_monitor_owned(it
->bs
);
344 } while (bs
&& bdrv_has_blk(bs
));
349 BlockDriverState
*bdrv_first(BdrvNextIterator
*it
)
351 *it
= (BdrvNextIterator
) {
352 .phase
= BDRV_NEXT_BACKEND_ROOTS
,
355 return bdrv_next(it
);
359 * Add a BlockBackend into the list of backends referenced by the monitor, with
360 * the given @name acting as the handle for the monitor.
361 * Strictly for use by blockdev.c.
363 * @name must not be null or empty.
365 * Returns true on success and false on failure. In the latter case, an Error
366 * object is returned through @errp.
368 bool monitor_add_blk(BlockBackend
*blk
, const char *name
, Error
**errp
)
371 assert(name
&& name
[0]);
373 if (!id_wellformed(name
)) {
374 error_setg(errp
, "Invalid device name");
377 if (blk_by_name(name
)) {
378 error_setg(errp
, "Device with id '%s' already exists", name
);
381 if (bdrv_find_node(name
)) {
383 "Device name '%s' conflicts with an existing node name",
388 blk
->name
= g_strdup(name
);
389 QTAILQ_INSERT_TAIL(&monitor_block_backends
, blk
, monitor_link
);
394 * Remove a BlockBackend from the list of backends referenced by the monitor.
395 * Strictly for use by blockdev.c.
397 void monitor_remove_blk(BlockBackend
*blk
)
403 QTAILQ_REMOVE(&monitor_block_backends
, blk
, monitor_link
);
409 * Return @blk's name, a non-null string.
410 * Returns an empty string iff @blk is not referenced by the monitor.
412 const char *blk_name(BlockBackend
*blk
)
414 return blk
->name
?: "";
418 * Return the BlockBackend with name @name if it exists, else null.
419 * @name must not be null.
421 BlockBackend
*blk_by_name(const char *name
)
423 BlockBackend
*blk
= NULL
;
426 while ((blk
= blk_next(blk
)) != NULL
) {
427 if (!strcmp(name
, blk
->name
)) {
435 * Return the BlockDriverState attached to @blk if any, else null.
437 BlockDriverState
*blk_bs(BlockBackend
*blk
)
439 return blk
->root
? blk
->root
->bs
: NULL
;
442 static BlockBackend
*bdrv_first_blk(BlockDriverState
*bs
)
445 QLIST_FOREACH(child
, &bs
->parents
, next_parent
) {
446 if (child
->role
== &child_root
) {
447 return child
->opaque
;
455 * Returns true if @bs has an associated BlockBackend.
457 bool bdrv_has_blk(BlockDriverState
*bs
)
459 return bdrv_first_blk(bs
) != NULL
;
463 * Returns true if @bs has only BlockBackends as parents.
465 bool bdrv_is_root_node(BlockDriverState
*bs
)
469 QLIST_FOREACH(c
, &bs
->parents
, next_parent
) {
470 if (c
->role
!= &child_root
) {
479 * Return @blk's DriveInfo if any, else null.
481 DriveInfo
*blk_legacy_dinfo(BlockBackend
*blk
)
483 return blk
->legacy_dinfo
;
487 * Set @blk's DriveInfo to @dinfo, and return it.
488 * @blk must not have a DriveInfo set already.
489 * No other BlockBackend may have the same DriveInfo set.
491 DriveInfo
*blk_set_legacy_dinfo(BlockBackend
*blk
, DriveInfo
*dinfo
)
493 assert(!blk
->legacy_dinfo
);
494 return blk
->legacy_dinfo
= dinfo
;
498 * Return the BlockBackend with DriveInfo @dinfo.
501 BlockBackend
*blk_by_legacy_dinfo(DriveInfo
*dinfo
)
503 BlockBackend
*blk
= NULL
;
505 while ((blk
= blk_next(blk
)) != NULL
) {
506 if (blk
->legacy_dinfo
== dinfo
) {
514 * Returns a pointer to the publicly accessible fields of @blk.
516 BlockBackendPublic
*blk_get_public(BlockBackend
*blk
)
522 * Returns a BlockBackend given the associated @public fields.
524 BlockBackend
*blk_by_public(BlockBackendPublic
*public)
526 return container_of(public, BlockBackend
, public);
530 * Disassociates the currently associated BlockDriverState from @blk.
532 void blk_remove_bs(BlockBackend
*blk
)
534 notifier_list_notify(&blk
->remove_bs_notifiers
, blk
);
535 if (blk
->public.throttle_state
) {
536 throttle_timers_detach_aio_context(&blk
->public.throttle_timers
);
539 blk_update_root_state(blk
);
541 bdrv_root_unref_child(blk
->root
);
546 * Associates a new BlockDriverState with @blk.
548 int blk_insert_bs(BlockBackend
*blk
, BlockDriverState
*bs
, Error
**errp
)
550 blk
->root
= bdrv_root_attach_child(bs
, "root", &child_root
,
551 blk
->perm
, blk
->shared_perm
, blk
, errp
);
552 if (blk
->root
== NULL
) {
557 notifier_list_notify(&blk
->insert_bs_notifiers
, blk
);
558 if (blk
->public.throttle_state
) {
559 throttle_timers_attach_aio_context(
560 &blk
->public.throttle_timers
, bdrv_get_aio_context(bs
));
567 * Sets the permission bitmasks that the user of the BlockBackend needs.
569 int blk_set_perm(BlockBackend
*blk
, uint64_t perm
, uint64_t shared_perm
,
575 ret
= bdrv_child_try_set_perm(blk
->root
, perm
, shared_perm
, errp
);
582 blk
->shared_perm
= shared_perm
;
587 void blk_get_perm(BlockBackend
*blk
, uint64_t *perm
, uint64_t *shared_perm
)
590 *shared_perm
= blk
->shared_perm
;
593 static int blk_do_attach_dev(BlockBackend
*blk
, void *dev
)
600 blk
->legacy_dev
= false;
601 blk_iostatus_reset(blk
);
606 * Attach device model @dev to @blk.
607 * Return 0 on success, -EBUSY when a device model is attached already.
609 int blk_attach_dev(BlockBackend
*blk
, DeviceState
*dev
)
611 return blk_do_attach_dev(blk
, dev
);
615 * Attach device model @dev to @blk.
616 * @blk must not have a device model attached already.
617 * TODO qdevified devices don't use this, remove when devices are qdevified
619 void blk_attach_dev_legacy(BlockBackend
*blk
, void *dev
)
621 if (blk_do_attach_dev(blk
, dev
) < 0) {
624 blk
->legacy_dev
= true;
628 * Detach device model @dev from @blk.
629 * @dev must be currently attached to @blk.
631 void blk_detach_dev(BlockBackend
*blk
, void *dev
)
632 /* TODO change to DeviceState *dev when all users are qdevified */
634 assert(blk
->dev
== dev
);
637 blk
->dev_opaque
= NULL
;
638 blk
->guest_block_size
= 512;
639 blk_set_perm(blk
, 0, BLK_PERM_ALL
, &error_abort
);
644 * Return the device model attached to @blk if any, else null.
646 void *blk_get_attached_dev(BlockBackend
*blk
)
647 /* TODO change to return DeviceState * when all users are qdevified */
652 /* Return the qdev ID, or if no ID is assigned the QOM path, of the block
653 * device attached to the BlockBackend. */
654 static char *blk_get_attached_dev_id(BlockBackend
*blk
)
658 assert(!blk
->legacy_dev
);
663 } else if (dev
->id
) {
664 return g_strdup(dev
->id
);
666 return object_get_canonical_path(OBJECT(dev
));
670 * Return the BlockBackend which has the device model @dev attached if it
673 * @dev must not be null.
675 BlockBackend
*blk_by_dev(void *dev
)
677 BlockBackend
*blk
= NULL
;
680 while ((blk
= blk_all_next(blk
)) != NULL
) {
681 if (blk
->dev
== dev
) {
689 * Set @blk's device model callbacks to @ops.
690 * @opaque is the opaque argument to pass to the callbacks.
691 * This is for use by device models.
693 void blk_set_dev_ops(BlockBackend
*blk
, const BlockDevOps
*ops
,
696 /* All drivers that use blk_set_dev_ops() are qdevified and we want to keep
697 * it that way, so we can assume blk->dev is a DeviceState if blk->dev_ops
699 assert(!blk
->legacy_dev
);
702 blk
->dev_opaque
= opaque
;
706 * Notify @blk's attached device model of media change.
708 * If @load is true, notify of media load. This action can fail, meaning that
709 * the medium cannot be loaded. @errp is set then.
711 * If @load is false, notify of media eject. This can never fail.
713 * Also send DEVICE_TRAY_MOVED events as appropriate.
715 void blk_dev_change_media_cb(BlockBackend
*blk
, bool load
, Error
**errp
)
717 if (blk
->dev_ops
&& blk
->dev_ops
->change_media_cb
) {
718 bool tray_was_open
, tray_is_open
;
719 Error
*local_err
= NULL
;
721 assert(!blk
->legacy_dev
);
723 tray_was_open
= blk_dev_is_tray_open(blk
);
724 blk
->dev_ops
->change_media_cb(blk
->dev_opaque
, load
, &local_err
);
726 assert(load
== true);
727 error_propagate(errp
, local_err
);
730 tray_is_open
= blk_dev_is_tray_open(blk
);
732 if (tray_was_open
!= tray_is_open
) {
733 char *id
= blk_get_attached_dev_id(blk
);
734 qapi_event_send_device_tray_moved(blk_name(blk
), id
, tray_is_open
,
741 static void blk_root_change_media(BdrvChild
*child
, bool load
)
743 blk_dev_change_media_cb(child
->opaque
, load
, NULL
);
747 * Does @blk's attached device model have removable media?
748 * %true if no device model is attached.
750 bool blk_dev_has_removable_media(BlockBackend
*blk
)
752 return !blk
->dev
|| (blk
->dev_ops
&& blk
->dev_ops
->change_media_cb
);
756 * Does @blk's attached device model have a tray?
758 bool blk_dev_has_tray(BlockBackend
*blk
)
760 return blk
->dev_ops
&& blk
->dev_ops
->is_tray_open
;
764 * Notify @blk's attached device model of a media eject request.
765 * If @force is true, the medium is about to be yanked out forcefully.
767 void blk_dev_eject_request(BlockBackend
*blk
, bool force
)
769 if (blk
->dev_ops
&& blk
->dev_ops
->eject_request_cb
) {
770 blk
->dev_ops
->eject_request_cb(blk
->dev_opaque
, force
);
775 * Does @blk's attached device model have a tray, and is it open?
777 bool blk_dev_is_tray_open(BlockBackend
*blk
)
779 if (blk_dev_has_tray(blk
)) {
780 return blk
->dev_ops
->is_tray_open(blk
->dev_opaque
);
786 * Does @blk's attached device model have the medium locked?
787 * %false if the device model has no such lock.
789 bool blk_dev_is_medium_locked(BlockBackend
*blk
)
791 if (blk
->dev_ops
&& blk
->dev_ops
->is_medium_locked
) {
792 return blk
->dev_ops
->is_medium_locked(blk
->dev_opaque
);
798 * Notify @blk's attached device model of a backend size change.
800 static void blk_root_resize(BdrvChild
*child
)
802 BlockBackend
*blk
= child
->opaque
;
804 if (blk
->dev_ops
&& blk
->dev_ops
->resize_cb
) {
805 blk
->dev_ops
->resize_cb(blk
->dev_opaque
);
809 void blk_iostatus_enable(BlockBackend
*blk
)
811 blk
->iostatus_enabled
= true;
812 blk
->iostatus
= BLOCK_DEVICE_IO_STATUS_OK
;
815 /* The I/O status is only enabled if the drive explicitly
816 * enables it _and_ the VM is configured to stop on errors */
817 bool blk_iostatus_is_enabled(const BlockBackend
*blk
)
819 return (blk
->iostatus_enabled
&&
820 (blk
->on_write_error
== BLOCKDEV_ON_ERROR_ENOSPC
||
821 blk
->on_write_error
== BLOCKDEV_ON_ERROR_STOP
||
822 blk
->on_read_error
== BLOCKDEV_ON_ERROR_STOP
));
825 BlockDeviceIoStatus
blk_iostatus(const BlockBackend
*blk
)
827 return blk
->iostatus
;
830 void blk_iostatus_disable(BlockBackend
*blk
)
832 blk
->iostatus_enabled
= false;
835 void blk_iostatus_reset(BlockBackend
*blk
)
837 if (blk_iostatus_is_enabled(blk
)) {
838 BlockDriverState
*bs
= blk_bs(blk
);
839 blk
->iostatus
= BLOCK_DEVICE_IO_STATUS_OK
;
841 block_job_iostatus_reset(bs
->job
);
846 void blk_iostatus_set_err(BlockBackend
*blk
, int error
)
848 assert(blk_iostatus_is_enabled(blk
));
849 if (blk
->iostatus
== BLOCK_DEVICE_IO_STATUS_OK
) {
850 blk
->iostatus
= error
== ENOSPC
? BLOCK_DEVICE_IO_STATUS_NOSPACE
:
851 BLOCK_DEVICE_IO_STATUS_FAILED
;
855 void blk_set_allow_write_beyond_eof(BlockBackend
*blk
, bool allow
)
857 blk
->allow_write_beyond_eof
= allow
;
860 static int blk_check_byte_request(BlockBackend
*blk
, int64_t offset
,
865 if (size
> INT_MAX
) {
869 if (!blk_is_available(blk
)) {
877 if (!blk
->allow_write_beyond_eof
) {
878 len
= blk_getlength(blk
);
883 if (offset
> len
|| len
- offset
< size
) {
891 int coroutine_fn
blk_co_preadv(BlockBackend
*blk
, int64_t offset
,
892 unsigned int bytes
, QEMUIOVector
*qiov
,
893 BdrvRequestFlags flags
)
896 BlockDriverState
*bs
= blk_bs(blk
);
898 trace_blk_co_preadv(blk
, bs
, offset
, bytes
, flags
);
900 ret
= blk_check_byte_request(blk
, offset
, bytes
);
905 bdrv_inc_in_flight(bs
);
907 /* throttling disk I/O */
908 if (blk
->public.throttle_state
) {
909 throttle_group_co_io_limits_intercept(blk
, bytes
, false);
912 ret
= bdrv_co_preadv(blk
->root
, offset
, bytes
, qiov
, flags
);
913 bdrv_dec_in_flight(bs
);
917 int coroutine_fn
blk_co_pwritev(BlockBackend
*blk
, int64_t offset
,
918 unsigned int bytes
, QEMUIOVector
*qiov
,
919 BdrvRequestFlags flags
)
922 BlockDriverState
*bs
= blk_bs(blk
);
924 trace_blk_co_pwritev(blk
, bs
, offset
, bytes
, flags
);
926 ret
= blk_check_byte_request(blk
, offset
, bytes
);
931 bdrv_inc_in_flight(bs
);
933 /* throttling disk I/O */
934 if (blk
->public.throttle_state
) {
935 throttle_group_co_io_limits_intercept(blk
, bytes
, true);
938 if (!blk
->enable_write_cache
) {
939 flags
|= BDRV_REQ_FUA
;
942 ret
= bdrv_co_pwritev(blk
->root
, offset
, bytes
, qiov
, flags
);
943 bdrv_dec_in_flight(bs
);
947 typedef struct BlkRwCo
{
952 BdrvRequestFlags flags
;
955 static void blk_read_entry(void *opaque
)
957 BlkRwCo
*rwco
= opaque
;
959 rwco
->ret
= blk_co_preadv(rwco
->blk
, rwco
->offset
, rwco
->qiov
->size
,
960 rwco
->qiov
, rwco
->flags
);
963 static void blk_write_entry(void *opaque
)
965 BlkRwCo
*rwco
= opaque
;
967 rwco
->ret
= blk_co_pwritev(rwco
->blk
, rwco
->offset
, rwco
->qiov
->size
,
968 rwco
->qiov
, rwco
->flags
);
971 static int blk_prw(BlockBackend
*blk
, int64_t offset
, uint8_t *buf
,
972 int64_t bytes
, CoroutineEntry co_entry
,
973 BdrvRequestFlags flags
)
979 iov
= (struct iovec
) {
983 qemu_iovec_init_external(&qiov
, &iov
, 1);
993 if (qemu_in_coroutine()) {
994 /* Fast-path if already in coroutine context */
997 Coroutine
*co
= qemu_coroutine_create(co_entry
, &rwco
);
998 qemu_coroutine_enter(co
);
999 BDRV_POLL_WHILE(blk_bs(blk
), rwco
.ret
== NOT_DONE
);
1005 int blk_pread_unthrottled(BlockBackend
*blk
, int64_t offset
, uint8_t *buf
,
1010 ret
= blk_check_byte_request(blk
, offset
, count
);
1015 blk_root_drained_begin(blk
->root
);
1016 ret
= blk_pread(blk
, offset
, buf
, count
);
1017 blk_root_drained_end(blk
->root
);
1021 int blk_pwrite_zeroes(BlockBackend
*blk
, int64_t offset
,
1022 int count
, BdrvRequestFlags flags
)
1024 return blk_prw(blk
, offset
, NULL
, count
, blk_write_entry
,
1025 flags
| BDRV_REQ_ZERO_WRITE
);
1028 int blk_make_zero(BlockBackend
*blk
, BdrvRequestFlags flags
)
1030 return bdrv_make_zero(blk
->root
, flags
);
1033 static void error_callback_bh(void *opaque
)
1035 struct BlockBackendAIOCB
*acb
= opaque
;
1037 bdrv_dec_in_flight(acb
->common
.bs
);
1038 acb
->common
.cb(acb
->common
.opaque
, acb
->ret
);
1039 qemu_aio_unref(acb
);
1042 BlockAIOCB
*blk_abort_aio_request(BlockBackend
*blk
,
1043 BlockCompletionFunc
*cb
,
1044 void *opaque
, int ret
)
1046 struct BlockBackendAIOCB
*acb
;
1048 bdrv_inc_in_flight(blk_bs(blk
));
1049 acb
= blk_aio_get(&block_backend_aiocb_info
, blk
, cb
, opaque
);
1053 aio_bh_schedule_oneshot(blk_get_aio_context(blk
), error_callback_bh
, acb
);
1054 return &acb
->common
;
1057 typedef struct BlkAioEmAIOCB
{
1064 static const AIOCBInfo blk_aio_em_aiocb_info
= {
1065 .aiocb_size
= sizeof(BlkAioEmAIOCB
),
1068 static void blk_aio_complete(BlkAioEmAIOCB
*acb
)
1070 if (acb
->has_returned
) {
1071 bdrv_dec_in_flight(acb
->common
.bs
);
1072 acb
->common
.cb(acb
->common
.opaque
, acb
->rwco
.ret
);
1073 qemu_aio_unref(acb
);
1077 static void blk_aio_complete_bh(void *opaque
)
1079 BlkAioEmAIOCB
*acb
= opaque
;
1080 assert(acb
->has_returned
);
1081 blk_aio_complete(acb
);
1084 static BlockAIOCB
*blk_aio_prwv(BlockBackend
*blk
, int64_t offset
, int bytes
,
1085 QEMUIOVector
*qiov
, CoroutineEntry co_entry
,
1086 BdrvRequestFlags flags
,
1087 BlockCompletionFunc
*cb
, void *opaque
)
1092 bdrv_inc_in_flight(blk_bs(blk
));
1093 acb
= blk_aio_get(&blk_aio_em_aiocb_info
, blk
, cb
, opaque
);
1094 acb
->rwco
= (BlkRwCo
) {
1102 acb
->has_returned
= false;
1104 co
= qemu_coroutine_create(co_entry
, acb
);
1105 qemu_coroutine_enter(co
);
1107 acb
->has_returned
= true;
1108 if (acb
->rwco
.ret
!= NOT_DONE
) {
1109 aio_bh_schedule_oneshot(blk_get_aio_context(blk
),
1110 blk_aio_complete_bh
, acb
);
1113 return &acb
->common
;
1116 static void blk_aio_read_entry(void *opaque
)
1118 BlkAioEmAIOCB
*acb
= opaque
;
1119 BlkRwCo
*rwco
= &acb
->rwco
;
1121 assert(rwco
->qiov
->size
== acb
->bytes
);
1122 rwco
->ret
= blk_co_preadv(rwco
->blk
, rwco
->offset
, acb
->bytes
,
1123 rwco
->qiov
, rwco
->flags
);
1124 blk_aio_complete(acb
);
1127 static void blk_aio_write_entry(void *opaque
)
1129 BlkAioEmAIOCB
*acb
= opaque
;
1130 BlkRwCo
*rwco
= &acb
->rwco
;
1132 assert(!rwco
->qiov
|| rwco
->qiov
->size
== acb
->bytes
);
1133 rwco
->ret
= blk_co_pwritev(rwco
->blk
, rwco
->offset
, acb
->bytes
,
1134 rwco
->qiov
, rwco
->flags
);
1135 blk_aio_complete(acb
);
1138 BlockAIOCB
*blk_aio_pwrite_zeroes(BlockBackend
*blk
, int64_t offset
,
1139 int count
, BdrvRequestFlags flags
,
1140 BlockCompletionFunc
*cb
, void *opaque
)
1142 return blk_aio_prwv(blk
, offset
, count
, NULL
, blk_aio_write_entry
,
1143 flags
| BDRV_REQ_ZERO_WRITE
, cb
, opaque
);
1146 int blk_pread(BlockBackend
*blk
, int64_t offset
, void *buf
, int count
)
1148 int ret
= blk_prw(blk
, offset
, buf
, count
, blk_read_entry
, 0);
1155 int blk_pwrite(BlockBackend
*blk
, int64_t offset
, const void *buf
, int count
,
1156 BdrvRequestFlags flags
)
1158 int ret
= blk_prw(blk
, offset
, (void *) buf
, count
, blk_write_entry
,
1166 int64_t blk_getlength(BlockBackend
*blk
)
1168 if (!blk_is_available(blk
)) {
1172 return bdrv_getlength(blk_bs(blk
));
1175 void blk_get_geometry(BlockBackend
*blk
, uint64_t *nb_sectors_ptr
)
1178 *nb_sectors_ptr
= 0;
1180 bdrv_get_geometry(blk_bs(blk
), nb_sectors_ptr
);
1184 int64_t blk_nb_sectors(BlockBackend
*blk
)
1186 if (!blk_is_available(blk
)) {
1190 return bdrv_nb_sectors(blk_bs(blk
));
1193 BlockAIOCB
*blk_aio_preadv(BlockBackend
*blk
, int64_t offset
,
1194 QEMUIOVector
*qiov
, BdrvRequestFlags flags
,
1195 BlockCompletionFunc
*cb
, void *opaque
)
1197 return blk_aio_prwv(blk
, offset
, qiov
->size
, qiov
,
1198 blk_aio_read_entry
, flags
, cb
, opaque
);
1201 BlockAIOCB
*blk_aio_pwritev(BlockBackend
*blk
, int64_t offset
,
1202 QEMUIOVector
*qiov
, BdrvRequestFlags flags
,
1203 BlockCompletionFunc
*cb
, void *opaque
)
1205 return blk_aio_prwv(blk
, offset
, qiov
->size
, qiov
,
1206 blk_aio_write_entry
, flags
, cb
, opaque
);
1209 static void blk_aio_flush_entry(void *opaque
)
1211 BlkAioEmAIOCB
*acb
= opaque
;
1212 BlkRwCo
*rwco
= &acb
->rwco
;
1214 rwco
->ret
= blk_co_flush(rwco
->blk
);
1215 blk_aio_complete(acb
);
1218 BlockAIOCB
*blk_aio_flush(BlockBackend
*blk
,
1219 BlockCompletionFunc
*cb
, void *opaque
)
1221 return blk_aio_prwv(blk
, 0, 0, NULL
, blk_aio_flush_entry
, 0, cb
, opaque
);
1224 static void blk_aio_pdiscard_entry(void *opaque
)
1226 BlkAioEmAIOCB
*acb
= opaque
;
1227 BlkRwCo
*rwco
= &acb
->rwco
;
1229 rwco
->ret
= blk_co_pdiscard(rwco
->blk
, rwco
->offset
, acb
->bytes
);
1230 blk_aio_complete(acb
);
1233 BlockAIOCB
*blk_aio_pdiscard(BlockBackend
*blk
,
1234 int64_t offset
, int count
,
1235 BlockCompletionFunc
*cb
, void *opaque
)
1237 return blk_aio_prwv(blk
, offset
, count
, NULL
, blk_aio_pdiscard_entry
, 0,
1241 void blk_aio_cancel(BlockAIOCB
*acb
)
1243 bdrv_aio_cancel(acb
);
1246 void blk_aio_cancel_async(BlockAIOCB
*acb
)
1248 bdrv_aio_cancel_async(acb
);
1251 int blk_co_ioctl(BlockBackend
*blk
, unsigned long int req
, void *buf
)
1253 if (!blk_is_available(blk
)) {
1257 return bdrv_co_ioctl(blk_bs(blk
), req
, buf
);
1260 static void blk_ioctl_entry(void *opaque
)
1262 BlkRwCo
*rwco
= opaque
;
1263 rwco
->ret
= blk_co_ioctl(rwco
->blk
, rwco
->offset
,
1264 rwco
->qiov
->iov
[0].iov_base
);
1267 int blk_ioctl(BlockBackend
*blk
, unsigned long int req
, void *buf
)
1269 return blk_prw(blk
, req
, buf
, 0, blk_ioctl_entry
, 0);
1272 static void blk_aio_ioctl_entry(void *opaque
)
1274 BlkAioEmAIOCB
*acb
= opaque
;
1275 BlkRwCo
*rwco
= &acb
->rwco
;
1277 rwco
->ret
= blk_co_ioctl(rwco
->blk
, rwco
->offset
,
1278 rwco
->qiov
->iov
[0].iov_base
);
1279 blk_aio_complete(acb
);
1282 BlockAIOCB
*blk_aio_ioctl(BlockBackend
*blk
, unsigned long int req
, void *buf
,
1283 BlockCompletionFunc
*cb
, void *opaque
)
1288 iov
= (struct iovec
) {
1292 qemu_iovec_init_external(&qiov
, &iov
, 1);
1294 return blk_aio_prwv(blk
, req
, 0, &qiov
, blk_aio_ioctl_entry
, 0, cb
, opaque
);
1297 int blk_co_pdiscard(BlockBackend
*blk
, int64_t offset
, int count
)
1299 int ret
= blk_check_byte_request(blk
, offset
, count
);
1304 return bdrv_co_pdiscard(blk_bs(blk
), offset
, count
);
1307 int blk_co_flush(BlockBackend
*blk
)
1309 if (!blk_is_available(blk
)) {
1313 return bdrv_co_flush(blk_bs(blk
));
1316 static void blk_flush_entry(void *opaque
)
1318 BlkRwCo
*rwco
= opaque
;
1319 rwco
->ret
= blk_co_flush(rwco
->blk
);
1322 int blk_flush(BlockBackend
*blk
)
1324 return blk_prw(blk
, 0, NULL
, 0, blk_flush_entry
, 0);
1327 void blk_drain(BlockBackend
*blk
)
1330 bdrv_drain(blk_bs(blk
));
1334 void blk_drain_all(void)
1339 void blk_set_on_error(BlockBackend
*blk
, BlockdevOnError on_read_error
,
1340 BlockdevOnError on_write_error
)
1342 blk
->on_read_error
= on_read_error
;
1343 blk
->on_write_error
= on_write_error
;
1346 BlockdevOnError
blk_get_on_error(BlockBackend
*blk
, bool is_read
)
1348 return is_read
? blk
->on_read_error
: blk
->on_write_error
;
1351 BlockErrorAction
blk_get_error_action(BlockBackend
*blk
, bool is_read
,
1354 BlockdevOnError on_err
= blk_get_on_error(blk
, is_read
);
1357 case BLOCKDEV_ON_ERROR_ENOSPC
:
1358 return (error
== ENOSPC
) ?
1359 BLOCK_ERROR_ACTION_STOP
: BLOCK_ERROR_ACTION_REPORT
;
1360 case BLOCKDEV_ON_ERROR_STOP
:
1361 return BLOCK_ERROR_ACTION_STOP
;
1362 case BLOCKDEV_ON_ERROR_REPORT
:
1363 return BLOCK_ERROR_ACTION_REPORT
;
1364 case BLOCKDEV_ON_ERROR_IGNORE
:
1365 return BLOCK_ERROR_ACTION_IGNORE
;
1366 case BLOCKDEV_ON_ERROR_AUTO
:
1372 static void send_qmp_error_event(BlockBackend
*blk
,
1373 BlockErrorAction action
,
1374 bool is_read
, int error
)
1376 IoOperationType optype
;
1378 optype
= is_read
? IO_OPERATION_TYPE_READ
: IO_OPERATION_TYPE_WRITE
;
1379 qapi_event_send_block_io_error(blk_name(blk
),
1380 bdrv_get_node_name(blk_bs(blk
)), optype
,
1381 action
, blk_iostatus_is_enabled(blk
),
1382 error
== ENOSPC
, strerror(error
),
1386 /* This is done by device models because, while the block layer knows
1387 * about the error, it does not know whether an operation comes from
1388 * the device or the block layer (from a job, for example).
1390 void blk_error_action(BlockBackend
*blk
, BlockErrorAction action
,
1391 bool is_read
, int error
)
1395 if (action
== BLOCK_ERROR_ACTION_STOP
) {
1396 /* First set the iostatus, so that "info block" returns an iostatus
1397 * that matches the events raised so far (an additional error iostatus
1398 * is fine, but not a lost one).
1400 blk_iostatus_set_err(blk
, error
);
1402 /* Then raise the request to stop the VM and the event.
1403 * qemu_system_vmstop_request_prepare has two effects. First,
1404 * it ensures that the STOP event always comes after the
1405 * BLOCK_IO_ERROR event. Second, it ensures that even if management
1406 * can observe the STOP event and do a "cont" before the STOP
1407 * event is issued, the VM will not stop. In this case, vm_start()
1408 * also ensures that the STOP/RESUME pair of events is emitted.
1410 qemu_system_vmstop_request_prepare();
1411 send_qmp_error_event(blk
, action
, is_read
, error
);
1412 qemu_system_vmstop_request(RUN_STATE_IO_ERROR
);
1414 send_qmp_error_event(blk
, action
, is_read
, error
);
1418 int blk_is_read_only(BlockBackend
*blk
)
1420 BlockDriverState
*bs
= blk_bs(blk
);
1423 return bdrv_is_read_only(bs
);
1425 return blk
->root_state
.read_only
;
1429 int blk_is_sg(BlockBackend
*blk
)
1431 BlockDriverState
*bs
= blk_bs(blk
);
1437 return bdrv_is_sg(bs
);
1440 int blk_enable_write_cache(BlockBackend
*blk
)
1442 return blk
->enable_write_cache
;
1445 void blk_set_enable_write_cache(BlockBackend
*blk
, bool wce
)
1447 blk
->enable_write_cache
= wce
;
1450 void blk_invalidate_cache(BlockBackend
*blk
, Error
**errp
)
1452 BlockDriverState
*bs
= blk_bs(blk
);
1455 error_setg(errp
, "Device '%s' has no medium", blk
->name
);
1459 bdrv_invalidate_cache(bs
, errp
);
1462 bool blk_is_inserted(BlockBackend
*blk
)
1464 BlockDriverState
*bs
= blk_bs(blk
);
1466 return bs
&& bdrv_is_inserted(bs
);
1469 bool blk_is_available(BlockBackend
*blk
)
1471 return blk_is_inserted(blk
) && !blk_dev_is_tray_open(blk
);
1474 void blk_lock_medium(BlockBackend
*blk
, bool locked
)
1476 BlockDriverState
*bs
= blk_bs(blk
);
1479 bdrv_lock_medium(bs
, locked
);
1483 void blk_eject(BlockBackend
*blk
, bool eject_flag
)
1485 BlockDriverState
*bs
= blk_bs(blk
);
1488 /* blk_eject is only called by qdevified devices */
1489 assert(!blk
->legacy_dev
);
1492 bdrv_eject(bs
, eject_flag
);
1495 /* Whether or not we ejected on the backend,
1496 * the frontend experienced a tray event. */
1497 id
= blk_get_attached_dev_id(blk
);
1498 qapi_event_send_device_tray_moved(blk_name(blk
), id
,
1499 eject_flag
, &error_abort
);
1503 int blk_get_flags(BlockBackend
*blk
)
1505 BlockDriverState
*bs
= blk_bs(blk
);
1508 return bdrv_get_flags(bs
);
1510 return blk
->root_state
.open_flags
;
1514 /* Returns the maximum transfer length, in bytes; guaranteed nonzero */
1515 uint32_t blk_get_max_transfer(BlockBackend
*blk
)
1517 BlockDriverState
*bs
= blk_bs(blk
);
1521 max
= bs
->bl
.max_transfer
;
1523 return MIN_NON_ZERO(max
, INT_MAX
);
1526 int blk_get_max_iov(BlockBackend
*blk
)
1528 return blk
->root
->bs
->bl
.max_iov
;
1531 void blk_set_guest_block_size(BlockBackend
*blk
, int align
)
1533 blk
->guest_block_size
= align
;
1536 void *blk_try_blockalign(BlockBackend
*blk
, size_t size
)
1538 return qemu_try_blockalign(blk
? blk_bs(blk
) : NULL
, size
);
1541 void *blk_blockalign(BlockBackend
*blk
, size_t size
)
1543 return qemu_blockalign(blk
? blk_bs(blk
) : NULL
, size
);
1546 bool blk_op_is_blocked(BlockBackend
*blk
, BlockOpType op
, Error
**errp
)
1548 BlockDriverState
*bs
= blk_bs(blk
);
1554 return bdrv_op_is_blocked(bs
, op
, errp
);
1557 void blk_op_unblock(BlockBackend
*blk
, BlockOpType op
, Error
*reason
)
1559 BlockDriverState
*bs
= blk_bs(blk
);
1562 bdrv_op_unblock(bs
, op
, reason
);
1566 void blk_op_block_all(BlockBackend
*blk
, Error
*reason
)
1568 BlockDriverState
*bs
= blk_bs(blk
);
1571 bdrv_op_block_all(bs
, reason
);
1575 void blk_op_unblock_all(BlockBackend
*blk
, Error
*reason
)
1577 BlockDriverState
*bs
= blk_bs(blk
);
1580 bdrv_op_unblock_all(bs
, reason
);
1584 AioContext
*blk_get_aio_context(BlockBackend
*blk
)
1586 BlockDriverState
*bs
= blk_bs(blk
);
1589 return bdrv_get_aio_context(bs
);
1591 return qemu_get_aio_context();
1595 static AioContext
*blk_aiocb_get_aio_context(BlockAIOCB
*acb
)
1597 BlockBackendAIOCB
*blk_acb
= DO_UPCAST(BlockBackendAIOCB
, common
, acb
);
1598 return blk_get_aio_context(blk_acb
->blk
);
1601 void blk_set_aio_context(BlockBackend
*blk
, AioContext
*new_context
)
1603 BlockDriverState
*bs
= blk_bs(blk
);
1606 if (blk
->public.throttle_state
) {
1607 throttle_timers_detach_aio_context(&blk
->public.throttle_timers
);
1609 bdrv_set_aio_context(bs
, new_context
);
1610 if (blk
->public.throttle_state
) {
1611 throttle_timers_attach_aio_context(&blk
->public.throttle_timers
,
1617 void blk_add_aio_context_notifier(BlockBackend
*blk
,
1618 void (*attached_aio_context
)(AioContext
*new_context
, void *opaque
),
1619 void (*detach_aio_context
)(void *opaque
), void *opaque
)
1621 BlockDriverState
*bs
= blk_bs(blk
);
1624 bdrv_add_aio_context_notifier(bs
, attached_aio_context
,
1625 detach_aio_context
, opaque
);
1629 void blk_remove_aio_context_notifier(BlockBackend
*blk
,
1630 void (*attached_aio_context
)(AioContext
*,
1632 void (*detach_aio_context
)(void *),
1635 BlockDriverState
*bs
= blk_bs(blk
);
1638 bdrv_remove_aio_context_notifier(bs
, attached_aio_context
,
1639 detach_aio_context
, opaque
);
1643 void blk_add_remove_bs_notifier(BlockBackend
*blk
, Notifier
*notify
)
1645 notifier_list_add(&blk
->remove_bs_notifiers
, notify
);
1648 void blk_add_insert_bs_notifier(BlockBackend
*blk
, Notifier
*notify
)
1650 notifier_list_add(&blk
->insert_bs_notifiers
, notify
);
1653 void blk_io_plug(BlockBackend
*blk
)
1655 BlockDriverState
*bs
= blk_bs(blk
);
1662 void blk_io_unplug(BlockBackend
*blk
)
1664 BlockDriverState
*bs
= blk_bs(blk
);
1671 BlockAcctStats
*blk_get_stats(BlockBackend
*blk
)
1676 void *blk_aio_get(const AIOCBInfo
*aiocb_info
, BlockBackend
*blk
,
1677 BlockCompletionFunc
*cb
, void *opaque
)
1679 return qemu_aio_get(aiocb_info
, blk_bs(blk
), cb
, opaque
);
1682 int coroutine_fn
blk_co_pwrite_zeroes(BlockBackend
*blk
, int64_t offset
,
1683 int count
, BdrvRequestFlags flags
)
1685 return blk_co_pwritev(blk
, offset
, count
, NULL
,
1686 flags
| BDRV_REQ_ZERO_WRITE
);
1689 int blk_pwrite_compressed(BlockBackend
*blk
, int64_t offset
, const void *buf
,
1692 return blk_prw(blk
, offset
, (void *) buf
, count
, blk_write_entry
,
1693 BDRV_REQ_WRITE_COMPRESSED
);
1696 int blk_truncate(BlockBackend
*blk
, int64_t offset
)
1698 if (!blk_is_available(blk
)) {
1702 return bdrv_truncate(blk
->root
, offset
);
1705 static void blk_pdiscard_entry(void *opaque
)
1707 BlkRwCo
*rwco
= opaque
;
1708 rwco
->ret
= blk_co_pdiscard(rwco
->blk
, rwco
->offset
, rwco
->qiov
->size
);
1711 int blk_pdiscard(BlockBackend
*blk
, int64_t offset
, int count
)
1713 return blk_prw(blk
, offset
, NULL
, count
, blk_pdiscard_entry
, 0);
1716 int blk_save_vmstate(BlockBackend
*blk
, const uint8_t *buf
,
1717 int64_t pos
, int size
)
1721 if (!blk_is_available(blk
)) {
1725 ret
= bdrv_save_vmstate(blk_bs(blk
), buf
, pos
, size
);
1730 if (ret
== size
&& !blk
->enable_write_cache
) {
1731 ret
= bdrv_flush(blk_bs(blk
));
1734 return ret
< 0 ? ret
: size
;
1737 int blk_load_vmstate(BlockBackend
*blk
, uint8_t *buf
, int64_t pos
, int size
)
1739 if (!blk_is_available(blk
)) {
1743 return bdrv_load_vmstate(blk_bs(blk
), buf
, pos
, size
);
1746 int blk_probe_blocksizes(BlockBackend
*blk
, BlockSizes
*bsz
)
1748 if (!blk_is_available(blk
)) {
1752 return bdrv_probe_blocksizes(blk_bs(blk
), bsz
);
1755 int blk_probe_geometry(BlockBackend
*blk
, HDGeometry
*geo
)
1757 if (!blk_is_available(blk
)) {
1761 return bdrv_probe_geometry(blk_bs(blk
), geo
);
1765 * Updates the BlockBackendRootState object with data from the currently
1766 * attached BlockDriverState.
1768 void blk_update_root_state(BlockBackend
*blk
)
1772 blk
->root_state
.open_flags
= blk
->root
->bs
->open_flags
;
1773 blk
->root_state
.read_only
= blk
->root
->bs
->read_only
;
1774 blk
->root_state
.detect_zeroes
= blk
->root
->bs
->detect_zeroes
;
1778 * Returns the detect-zeroes setting to be used for bdrv_open() of a
1779 * BlockDriverState which is supposed to inherit the root state.
1781 bool blk_get_detect_zeroes_from_root_state(BlockBackend
*blk
)
1783 return blk
->root_state
.detect_zeroes
;
1787 * Returns the flags to be used for bdrv_open() of a BlockDriverState which is
1788 * supposed to inherit the root state.
1790 int blk_get_open_flags_from_root_state(BlockBackend
*blk
)
1794 bs_flags
= blk
->root_state
.read_only
? 0 : BDRV_O_RDWR
;
1795 bs_flags
|= blk
->root_state
.open_flags
& ~BDRV_O_RDWR
;
1800 BlockBackendRootState
*blk_get_root_state(BlockBackend
*blk
)
1802 return &blk
->root_state
;
1805 int blk_commit_all(void)
1807 BlockBackend
*blk
= NULL
;
1809 while ((blk
= blk_all_next(blk
)) != NULL
) {
1810 AioContext
*aio_context
= blk_get_aio_context(blk
);
1812 aio_context_acquire(aio_context
);
1813 if (blk_is_inserted(blk
) && blk
->root
->bs
->backing
) {
1814 int ret
= bdrv_commit(blk
->root
->bs
);
1816 aio_context_release(aio_context
);
1820 aio_context_release(aio_context
);
1826 /* throttling disk I/O limits */
1827 void blk_set_io_limits(BlockBackend
*blk
, ThrottleConfig
*cfg
)
1829 throttle_group_config(blk
, cfg
);
1832 void blk_io_limits_disable(BlockBackend
*blk
)
1834 assert(blk
->public.throttle_state
);
1835 bdrv_drained_begin(blk_bs(blk
));
1836 throttle_group_unregister_blk(blk
);
1837 bdrv_drained_end(blk_bs(blk
));
1840 /* should be called before blk_set_io_limits if a limit is set */
1841 void blk_io_limits_enable(BlockBackend
*blk
, const char *group
)
1843 assert(!blk
->public.throttle_state
);
1844 throttle_group_register_blk(blk
, group
);
1847 void blk_io_limits_update_group(BlockBackend
*blk
, const char *group
)
1849 /* this BB is not part of any group */
1850 if (!blk
->public.throttle_state
) {
1854 /* this BB is a part of the same group than the one we want */
1855 if (!g_strcmp0(throttle_group_get_name(blk
), group
)) {
1859 /* need to change the group this bs belong to */
1860 blk_io_limits_disable(blk
);
1861 blk_io_limits_enable(blk
, group
);
1864 static void blk_root_drained_begin(BdrvChild
*child
)
1866 BlockBackend
*blk
= child
->opaque
;
1868 /* Note that blk->root may not be accessible here yet if we are just
1869 * attaching to a BlockDriverState that is drained. Use child instead. */
1871 if (blk
->public.io_limits_disabled
++ == 0) {
1872 throttle_group_restart_blk(blk
);
1876 static void blk_root_drained_end(BdrvChild
*child
)
1878 BlockBackend
*blk
= child
->opaque
;
1880 assert(blk
->public.io_limits_disabled
);
1881 --blk
->public.io_limits_disabled
;