4 * Copyright (C) 2014 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"
22 /* Number of coroutines to reserve per attached device model */
23 #define COROUTINE_POOL_RESERVATION 64
25 static AioContext *blk_aiocb_get_aio_context(BlockAIOCB *acb);
31 DriveInfo *legacy_dinfo; /* null unless created by drive_new() */
32 QTAILQ_ENTRY(BlockBackend) link; /* for block_backends */
33 QTAILQ_ENTRY(BlockBackend) monitor_link; /* for monitor_block_backends */
35 void *dev; /* attached device model, if any */
36 /* TODO change to DeviceState when all users are qdevified */
37 const BlockDevOps *dev_ops;
40 /* the block size for which the guest device expects atomicity */
43 /* If the BDS tree is removed, some of its options are stored here (which
44 * can be used to restore those options in the new BDS on insert) */
45 BlockBackendRootState root_state;
47 /* I/O stats (display with "info blockstats"). */
50 BlockdevOnError on_read_error, on_write_error;
51 bool iostatus_enabled;
52 BlockDeviceIoStatus iostatus;
54 bool allow_write_beyond_eof;
56 NotifierList remove_bs_notifiers, insert_bs_notifiers;
59 typedef struct BlockBackendAIOCB {
66 static const AIOCBInfo block_backend_aiocb_info = {
67 .get_aio_context = blk_aiocb_get_aio_context,
68 .aiocb_size = sizeof(BlockBackendAIOCB),
71 static void drive_info_del(DriveInfo *dinfo);
73 /* All BlockBackends */
74 static QTAILQ_HEAD(, BlockBackend) block_backends =
75 QTAILQ_HEAD_INITIALIZER(block_backends);
77 /* All BlockBackends referenced by the monitor and which are iterated through by
79 static QTAILQ_HEAD(, BlockBackend) monitor_block_backends =
80 QTAILQ_HEAD_INITIALIZER(monitor_block_backends);
83 * Create a new BlockBackend with a reference count of one.
84 * Store an error through @errp on failure, unless it's null.
85 * Return the new BlockBackend on success, null on failure.
87 BlockBackend *blk_new(Error **errp)
91 blk = g_new0(BlockBackend, 1);
93 notifier_list_init(&blk->remove_bs_notifiers);
94 notifier_list_init(&blk->insert_bs_notifiers);
95 QTAILQ_INSERT_TAIL(&block_backends, blk, link);
100 * Create a new BlockBackend with a new BlockDriverState attached.
101 * Otherwise just like blk_new(), which see.
103 BlockBackend *blk_new_with_bs(Error **errp)
106 BlockDriverState *bs;
113 bs = bdrv_new_root();
120 * Calls blk_new_with_bs() and then calls bdrv_open() on the BlockDriverState.
122 * Just as with bdrv_open(), after having called this function the reference to
123 * @options belongs to the block layer (even on failure).
125 * TODO: Remove @filename and @flags; it should be possible to specify a whole
126 * BDS tree just by specifying the @options QDict (or @reference,
127 * alternatively). At the time of adding this function, this is not possible,
128 * though, so callers of this function have to be able to specify @filename and
131 BlockBackend *blk_new_open(const char *filename, const char *reference,
132 QDict *options, int flags, Error **errp)
137 blk = blk_new_with_bs(errp);
143 ret = bdrv_open(&blk->bs, filename, reference, options, flags, errp);
152 static void blk_delete(BlockBackend *blk)
154 assert(!blk->refcnt);
160 assert(QLIST_EMPTY(&blk->remove_bs_notifiers.notifiers));
161 assert(QLIST_EMPTY(&blk->insert_bs_notifiers.notifiers));
162 if (blk->root_state.throttle_state) {
163 g_free(blk->root_state.throttle_group);
164 throttle_group_unref(blk->root_state.throttle_state);
166 QTAILQ_REMOVE(&block_backends, blk, link);
167 drive_info_del(blk->legacy_dinfo);
168 block_acct_cleanup(&blk->stats);
172 static void drive_info_del(DriveInfo *dinfo)
177 qemu_opts_del(dinfo->opts);
178 g_free(dinfo->serial);
182 int blk_get_refcnt(BlockBackend *blk)
184 return blk ? blk->refcnt : 0;
188 * Increment @blk's reference count.
189 * @blk must not be null.
191 void blk_ref(BlockBackend *blk)
197 * Decrement @blk's reference count.
198 * If this drops it to zero, destroy @blk.
199 * For convenience, do nothing if @blk is null.
201 void blk_unref(BlockBackend *blk)
204 assert(blk->refcnt > 0);
205 if (!--blk->refcnt) {
212 * Behaves similarly to blk_next() but iterates over all BlockBackends, even the
213 * ones which are hidden (i.e. are not referenced by the monitor).
215 static BlockBackend *blk_all_next(BlockBackend *blk)
217 return blk ? QTAILQ_NEXT(blk, link)
218 : QTAILQ_FIRST(&block_backends);
221 void blk_remove_all_bs(void)
223 BlockBackend *blk = NULL;
225 while ((blk = blk_all_next(blk)) != NULL) {
226 AioContext *ctx = blk_get_aio_context(blk);
228 aio_context_acquire(ctx);
232 aio_context_release(ctx);
237 * Return the monitor-owned BlockBackend after @blk.
238 * If @blk is null, return the first one.
239 * Else, return @blk's next sibling, which may be null.
241 * To iterate over all BlockBackends, do
242 * for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
246 BlockBackend *blk_next(BlockBackend *blk)
248 return blk ? QTAILQ_NEXT(blk, monitor_link)
249 : QTAILQ_FIRST(&monitor_block_backends);
253 * Add a BlockBackend into the list of backends referenced by the monitor, with
254 * the given @name acting as the handle for the monitor.
255 * Strictly for use by blockdev.c.
257 * @name must not be null or empty.
259 * Returns true on success and false on failure. In the latter case, an Error
260 * object is returned through @errp.
262 bool monitor_add_blk(BlockBackend *blk, const char *name, Error **errp)
265 assert(name && name[0]);
267 if (!id_wellformed(name)) {
268 error_setg(errp, "Invalid device name");
271 if (blk_by_name(name)) {
272 error_setg(errp, "Device with id '%s' already exists", name);
275 if (bdrv_find_node(name)) {
277 "Device name '%s' conflicts with an existing node name",
282 blk->name = g_strdup(name);
283 QTAILQ_INSERT_TAIL(&monitor_block_backends, blk, monitor_link);
288 * Remove a BlockBackend from the list of backends referenced by the monitor.
289 * Strictly for use by blockdev.c.
291 void monitor_remove_blk(BlockBackend *blk)
297 QTAILQ_REMOVE(&monitor_block_backends, blk, monitor_link);
303 * Return @blk's name, a non-null string.
304 * Returns an empty string iff @blk is not referenced by the monitor.
306 const char *blk_name(BlockBackend *blk)
308 return blk->name ?: "";
312 * Return the BlockBackend with name @name if it exists, else null.
313 * @name must not be null.
315 BlockBackend *blk_by_name(const char *name)
317 BlockBackend *blk = NULL;
320 while ((blk = blk_next(blk)) != NULL) {
321 if (!strcmp(name, blk->name)) {
329 * Return the BlockDriverState attached to @blk if any, else null.
331 BlockDriverState *blk_bs(BlockBackend *blk)
337 * Changes the BlockDriverState attached to @blk
339 void blk_set_bs(BlockBackend *blk, BlockDriverState *bs)
347 assert(bs->blk == NULL);
354 * Return @blk's DriveInfo if any, else null.
356 DriveInfo *blk_legacy_dinfo(BlockBackend *blk)
358 return blk->legacy_dinfo;
362 * Set @blk's DriveInfo to @dinfo, and return it.
363 * @blk must not have a DriveInfo set already.
364 * No other BlockBackend may have the same DriveInfo set.
366 DriveInfo *blk_set_legacy_dinfo(BlockBackend *blk, DriveInfo *dinfo)
368 assert(!blk->legacy_dinfo);
369 return blk->legacy_dinfo = dinfo;
373 * Return the BlockBackend with DriveInfo @dinfo.
376 BlockBackend *blk_by_legacy_dinfo(DriveInfo *dinfo)
378 BlockBackend *blk = NULL;
380 while ((blk = blk_next(blk)) != NULL) {
381 if (blk->legacy_dinfo == dinfo) {
389 * Disassociates the currently associated BlockDriverState from @blk.
391 void blk_remove_bs(BlockBackend *blk)
393 assert(blk->bs->blk == blk);
395 notifier_list_notify(&blk->remove_bs_notifiers, blk);
397 blk_update_root_state(blk);
405 * Associates a new BlockDriverState with @blk.
407 void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs)
409 assert(!blk->bs && !bs->blk);
414 notifier_list_notify(&blk->insert_bs_notifiers, blk);
418 * Attach device model @dev to @blk.
419 * Return 0 on success, -EBUSY when a device model is attached already.
421 int blk_attach_dev(BlockBackend *blk, void *dev)
422 /* TODO change to DeviceState *dev when all users are qdevified */
429 blk_iostatus_reset(blk);
434 * Attach device model @dev to @blk.
435 * @blk must not have a device model attached already.
436 * TODO qdevified devices don't use this, remove when devices are qdevified
438 void blk_attach_dev_nofail(BlockBackend *blk, void *dev)
440 if (blk_attach_dev(blk, dev) < 0) {
446 * Detach device model @dev from @blk.
447 * @dev must be currently attached to @blk.
449 void blk_detach_dev(BlockBackend *blk, void *dev)
450 /* TODO change to DeviceState *dev when all users are qdevified */
452 assert(blk->dev == dev);
455 blk->dev_opaque = NULL;
456 blk->guest_block_size = 512;
461 * Return the device model attached to @blk if any, else null.
463 void *blk_get_attached_dev(BlockBackend *blk)
464 /* TODO change to return DeviceState * when all users are qdevified */
470 * Set @blk's device model callbacks to @ops.
471 * @opaque is the opaque argument to pass to the callbacks.
472 * This is for use by device models.
474 void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops,
478 blk->dev_opaque = opaque;
482 * Notify @blk's attached device model of media change.
483 * If @load is true, notify of media load.
484 * Else, notify of media eject.
485 * Also send DEVICE_TRAY_MOVED events as appropriate.
487 void blk_dev_change_media_cb(BlockBackend *blk, bool load)
489 if (blk->dev_ops && blk->dev_ops->change_media_cb) {
490 bool tray_was_open, tray_is_open;
492 tray_was_open = blk_dev_is_tray_open(blk);
493 blk->dev_ops->change_media_cb(blk->dev_opaque, load);
494 tray_is_open = blk_dev_is_tray_open(blk);
496 if (tray_was_open != tray_is_open) {
497 qapi_event_send_device_tray_moved(blk_name(blk), tray_is_open,
504 * Does @blk's attached device model have removable media?
505 * %true if no device model is attached.
507 bool blk_dev_has_removable_media(BlockBackend *blk)
509 return !blk->dev || (blk->dev_ops && blk->dev_ops->change_media_cb);
513 * Does @blk's attached device model have a tray?
515 bool blk_dev_has_tray(BlockBackend *blk)
517 return blk->dev_ops && blk->dev_ops->is_tray_open;
521 * Notify @blk's attached device model of a media eject request.
522 * If @force is true, the medium is about to be yanked out forcefully.
524 void blk_dev_eject_request(BlockBackend *blk, bool force)
526 if (blk->dev_ops && blk->dev_ops->eject_request_cb) {
527 blk->dev_ops->eject_request_cb(blk->dev_opaque, force);
532 * Does @blk's attached device model have a tray, and is it open?
534 bool blk_dev_is_tray_open(BlockBackend *blk)
536 if (blk_dev_has_tray(blk)) {
537 return blk->dev_ops->is_tray_open(blk->dev_opaque);
543 * Does @blk's attached device model have the medium locked?
544 * %false if the device model has no such lock.
546 bool blk_dev_is_medium_locked(BlockBackend *blk)
548 if (blk->dev_ops && blk->dev_ops->is_medium_locked) {
549 return blk->dev_ops->is_medium_locked(blk->dev_opaque);
555 * Notify @blk's attached device model of a backend size change.
557 void blk_dev_resize_cb(BlockBackend *blk)
559 if (blk->dev_ops && blk->dev_ops->resize_cb) {
560 blk->dev_ops->resize_cb(blk->dev_opaque);
564 void blk_iostatus_enable(BlockBackend *blk)
566 blk->iostatus_enabled = true;
567 blk->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
570 /* The I/O status is only enabled if the drive explicitly
571 * enables it _and_ the VM is configured to stop on errors */
572 bool blk_iostatus_is_enabled(const BlockBackend *blk)
574 return (blk->iostatus_enabled &&
575 (blk->on_write_error == BLOCKDEV_ON_ERROR_ENOSPC ||
576 blk->on_write_error == BLOCKDEV_ON_ERROR_STOP ||
577 blk->on_read_error == BLOCKDEV_ON_ERROR_STOP));
580 BlockDeviceIoStatus blk_iostatus(const BlockBackend *blk)
582 return blk->iostatus;
585 void blk_iostatus_disable(BlockBackend *blk)
587 blk->iostatus_enabled = false;
590 void blk_iostatus_reset(BlockBackend *blk)
592 if (blk_iostatus_is_enabled(blk)) {
593 blk->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
594 if (blk->bs && blk->bs->job) {
595 block_job_iostatus_reset(blk->bs->job);
600 void blk_iostatus_set_err(BlockBackend *blk, int error)
602 assert(blk_iostatus_is_enabled(blk));
603 if (blk->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
604 blk->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE :
605 BLOCK_DEVICE_IO_STATUS_FAILED;
609 void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow)
611 blk->allow_write_beyond_eof = allow;
614 static int blk_check_byte_request(BlockBackend *blk, int64_t offset,
619 if (size > INT_MAX) {
623 if (!blk_is_available(blk)) {
631 if (!blk->allow_write_beyond_eof) {
632 len = blk_getlength(blk);
637 if (offset > len || len - offset < size) {
645 static int blk_check_request(BlockBackend *blk, int64_t sector_num,
648 if (sector_num < 0 || sector_num > INT64_MAX / BDRV_SECTOR_SIZE) {
652 if (nb_sectors < 0 || nb_sectors > INT_MAX / BDRV_SECTOR_SIZE) {
656 return blk_check_byte_request(blk, sector_num * BDRV_SECTOR_SIZE,
657 nb_sectors * BDRV_SECTOR_SIZE);
660 int blk_read(BlockBackend *blk, int64_t sector_num, uint8_t *buf,
663 int ret = blk_check_request(blk, sector_num, nb_sectors);
668 return bdrv_read(blk->bs, sector_num, buf, nb_sectors);
671 int blk_read_unthrottled(BlockBackend *blk, int64_t sector_num, uint8_t *buf,
674 int ret = blk_check_request(blk, sector_num, nb_sectors);
679 return bdrv_read_unthrottled(blk->bs, sector_num, buf, nb_sectors);
682 int blk_write(BlockBackend *blk, int64_t sector_num, const uint8_t *buf,
685 int ret = blk_check_request(blk, sector_num, nb_sectors);
690 return bdrv_write(blk->bs, sector_num, buf, nb_sectors);
693 int blk_write_zeroes(BlockBackend *blk, int64_t sector_num,
694 int nb_sectors, BdrvRequestFlags flags)
696 int ret = blk_check_request(blk, sector_num, nb_sectors);
701 return bdrv_write_zeroes(blk->bs, sector_num, nb_sectors, flags);
704 static void error_callback_bh(void *opaque)
706 struct BlockBackendAIOCB *acb = opaque;
707 qemu_bh_delete(acb->bh);
708 acb->common.cb(acb->common.opaque, acb->ret);
712 BlockAIOCB *blk_abort_aio_request(BlockBackend *blk,
713 BlockCompletionFunc *cb,
714 void *opaque, int ret)
716 struct BlockBackendAIOCB *acb;
719 acb = blk_aio_get(&block_backend_aiocb_info, blk, cb, opaque);
723 bh = aio_bh_new(blk_get_aio_context(blk), error_callback_bh, acb);
725 qemu_bh_schedule(bh);
730 BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t sector_num,
731 int nb_sectors, BdrvRequestFlags flags,
732 BlockCompletionFunc *cb, void *opaque)
734 int ret = blk_check_request(blk, sector_num, nb_sectors);
736 return blk_abort_aio_request(blk, cb, opaque, ret);
739 return bdrv_aio_write_zeroes(blk->bs, sector_num, nb_sectors, flags,
743 int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int count)
745 int ret = blk_check_byte_request(blk, offset, count);
750 return bdrv_pread(blk->bs, offset, buf, count);
753 int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int count)
755 int ret = blk_check_byte_request(blk, offset, count);
760 return bdrv_pwrite(blk->bs, offset, buf, count);
763 int64_t blk_getlength(BlockBackend *blk)
765 if (!blk_is_available(blk)) {
769 return bdrv_getlength(blk->bs);
772 void blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr)
777 bdrv_get_geometry(blk->bs, nb_sectors_ptr);
781 int64_t blk_nb_sectors(BlockBackend *blk)
783 if (!blk_is_available(blk)) {
787 return bdrv_nb_sectors(blk->bs);
790 BlockAIOCB *blk_aio_readv(BlockBackend *blk, int64_t sector_num,
791 QEMUIOVector *iov, int nb_sectors,
792 BlockCompletionFunc *cb, void *opaque)
794 int ret = blk_check_request(blk, sector_num, nb_sectors);
796 return blk_abort_aio_request(blk, cb, opaque, ret);
799 return bdrv_aio_readv(blk->bs, sector_num, iov, nb_sectors, cb, opaque);
802 BlockAIOCB *blk_aio_writev(BlockBackend *blk, int64_t sector_num,
803 QEMUIOVector *iov, int nb_sectors,
804 BlockCompletionFunc *cb, void *opaque)
806 int ret = blk_check_request(blk, sector_num, nb_sectors);
808 return blk_abort_aio_request(blk, cb, opaque, ret);
811 return bdrv_aio_writev(blk->bs, sector_num, iov, nb_sectors, cb, opaque);
814 BlockAIOCB *blk_aio_flush(BlockBackend *blk,
815 BlockCompletionFunc *cb, void *opaque)
817 if (!blk_is_available(blk)) {
818 return blk_abort_aio_request(blk, cb, opaque, -ENOMEDIUM);
821 return bdrv_aio_flush(blk->bs, cb, opaque);
824 BlockAIOCB *blk_aio_discard(BlockBackend *blk,
825 int64_t sector_num, int nb_sectors,
826 BlockCompletionFunc *cb, void *opaque)
828 int ret = blk_check_request(blk, sector_num, nb_sectors);
830 return blk_abort_aio_request(blk, cb, opaque, ret);
833 return bdrv_aio_discard(blk->bs, sector_num, nb_sectors, cb, opaque);
836 void blk_aio_cancel(BlockAIOCB *acb)
838 bdrv_aio_cancel(acb);
841 void blk_aio_cancel_async(BlockAIOCB *acb)
843 bdrv_aio_cancel_async(acb);
846 int blk_aio_multiwrite(BlockBackend *blk, BlockRequest *reqs, int num_reqs)
850 for (i = 0; i < num_reqs; i++) {
851 ret = blk_check_request(blk, reqs[i].sector, reqs[i].nb_sectors);
857 return bdrv_aio_multiwrite(blk->bs, reqs, num_reqs);
860 int blk_ioctl(BlockBackend *blk, unsigned long int req, void *buf)
862 if (!blk_is_available(blk)) {
866 return bdrv_ioctl(blk->bs, req, buf);
869 BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf,
870 BlockCompletionFunc *cb, void *opaque)
872 if (!blk_is_available(blk)) {
873 return blk_abort_aio_request(blk, cb, opaque, -ENOMEDIUM);
876 return bdrv_aio_ioctl(blk->bs, req, buf, cb, opaque);
879 int blk_co_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors)
881 int ret = blk_check_request(blk, sector_num, nb_sectors);
886 return bdrv_co_discard(blk->bs, sector_num, nb_sectors);
889 int blk_co_flush(BlockBackend *blk)
891 if (!blk_is_available(blk)) {
895 return bdrv_co_flush(blk->bs);
898 int blk_flush(BlockBackend *blk)
900 if (!blk_is_available(blk)) {
904 return bdrv_flush(blk->bs);
907 void blk_drain(BlockBackend *blk)
914 void blk_drain_all(void)
919 void blk_set_on_error(BlockBackend *blk, BlockdevOnError on_read_error,
920 BlockdevOnError on_write_error)
922 blk->on_read_error = on_read_error;
923 blk->on_write_error = on_write_error;
926 BlockdevOnError blk_get_on_error(BlockBackend *blk, bool is_read)
928 return is_read ? blk->on_read_error : blk->on_write_error;
931 BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read,
934 BlockdevOnError on_err = blk_get_on_error(blk, is_read);
937 case BLOCKDEV_ON_ERROR_ENOSPC:
938 return (error == ENOSPC) ?
939 BLOCK_ERROR_ACTION_STOP : BLOCK_ERROR_ACTION_REPORT;
940 case BLOCKDEV_ON_ERROR_STOP:
941 return BLOCK_ERROR_ACTION_STOP;
942 case BLOCKDEV_ON_ERROR_REPORT:
943 return BLOCK_ERROR_ACTION_REPORT;
944 case BLOCKDEV_ON_ERROR_IGNORE:
945 return BLOCK_ERROR_ACTION_IGNORE;
951 static void send_qmp_error_event(BlockBackend *blk,
952 BlockErrorAction action,
953 bool is_read, int error)
955 IoOperationType optype;
957 optype = is_read ? IO_OPERATION_TYPE_READ : IO_OPERATION_TYPE_WRITE;
958 qapi_event_send_block_io_error(blk_name(blk), optype, action,
959 blk_iostatus_is_enabled(blk),
960 error == ENOSPC, strerror(error),
964 /* This is done by device models because, while the block layer knows
965 * about the error, it does not know whether an operation comes from
966 * the device or the block layer (from a job, for example).
968 void blk_error_action(BlockBackend *blk, BlockErrorAction action,
969 bool is_read, int error)
973 if (action == BLOCK_ERROR_ACTION_STOP) {
974 /* First set the iostatus, so that "info block" returns an iostatus
975 * that matches the events raised so far (an additional error iostatus
976 * is fine, but not a lost one).
978 blk_iostatus_set_err(blk, error);
980 /* Then raise the request to stop the VM and the event.
981 * qemu_system_vmstop_request_prepare has two effects. First,
982 * it ensures that the STOP event always comes after the
983 * BLOCK_IO_ERROR event. Second, it ensures that even if management
984 * can observe the STOP event and do a "cont" before the STOP
985 * event is issued, the VM will not stop. In this case, vm_start()
986 * also ensures that the STOP/RESUME pair of events is emitted.
988 qemu_system_vmstop_request_prepare();
989 send_qmp_error_event(blk, action, is_read, error);
990 qemu_system_vmstop_request(RUN_STATE_IO_ERROR);
992 send_qmp_error_event(blk, action, is_read, error);
996 int blk_is_read_only(BlockBackend *blk)
999 return bdrv_is_read_only(blk->bs);
1001 return blk->root_state.read_only;
1005 int blk_is_sg(BlockBackend *blk)
1011 return bdrv_is_sg(blk->bs);
1014 int blk_enable_write_cache(BlockBackend *blk)
1017 return bdrv_enable_write_cache(blk->bs);
1019 return !!(blk->root_state.open_flags & BDRV_O_CACHE_WB);
1023 void blk_set_enable_write_cache(BlockBackend *blk, bool wce)
1026 bdrv_set_enable_write_cache(blk->bs, wce);
1029 blk->root_state.open_flags |= BDRV_O_CACHE_WB;
1031 blk->root_state.open_flags &= ~BDRV_O_CACHE_WB;
1036 void blk_invalidate_cache(BlockBackend *blk, Error **errp)
1039 error_setg(errp, "Device '%s' has no medium", blk->name);
1043 bdrv_invalidate_cache(blk->bs, errp);
1046 bool blk_is_inserted(BlockBackend *blk)
1048 return blk->bs && bdrv_is_inserted(blk->bs);
1051 bool blk_is_available(BlockBackend *blk)
1053 return blk_is_inserted(blk) && !blk_dev_is_tray_open(blk);
1056 void blk_lock_medium(BlockBackend *blk, bool locked)
1059 bdrv_lock_medium(blk->bs, locked);
1063 void blk_eject(BlockBackend *blk, bool eject_flag)
1066 bdrv_eject(blk->bs, eject_flag);
1070 int blk_get_flags(BlockBackend *blk)
1073 return bdrv_get_flags(blk->bs);
1075 return blk->root_state.open_flags;
1079 int blk_get_max_transfer_length(BlockBackend *blk)
1082 return blk->bs->bl.max_transfer_length;
1088 int blk_get_max_iov(BlockBackend *blk)
1090 return blk->bs->bl.max_iov;
1093 void blk_set_guest_block_size(BlockBackend *blk, int align)
1095 blk->guest_block_size = align;
1098 void *blk_try_blockalign(BlockBackend *blk, size_t size)
1100 return qemu_try_blockalign(blk ? blk->bs : NULL, size);
1103 void *blk_blockalign(BlockBackend *blk, size_t size)
1105 return qemu_blockalign(blk ? blk->bs : NULL, size);
1108 bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp)
1114 return bdrv_op_is_blocked(blk->bs, op, errp);
1117 void blk_op_unblock(BlockBackend *blk, BlockOpType op, Error *reason)
1120 bdrv_op_unblock(blk->bs, op, reason);
1124 void blk_op_block_all(BlockBackend *blk, Error *reason)
1127 bdrv_op_block_all(blk->bs, reason);
1131 void blk_op_unblock_all(BlockBackend *blk, Error *reason)
1134 bdrv_op_unblock_all(blk->bs, reason);
1138 AioContext *blk_get_aio_context(BlockBackend *blk)
1141 return bdrv_get_aio_context(blk->bs);
1143 return qemu_get_aio_context();
1147 static AioContext *blk_aiocb_get_aio_context(BlockAIOCB *acb)
1149 BlockBackendAIOCB *blk_acb = DO_UPCAST(BlockBackendAIOCB, common, acb);
1150 return blk_get_aio_context(blk_acb->blk);
1153 void blk_set_aio_context(BlockBackend *blk, AioContext *new_context)
1156 bdrv_set_aio_context(blk->bs, new_context);
1160 void blk_add_aio_context_notifier(BlockBackend *blk,
1161 void (*attached_aio_context)(AioContext *new_context, void *opaque),
1162 void (*detach_aio_context)(void *opaque), void *opaque)
1165 bdrv_add_aio_context_notifier(blk->bs, attached_aio_context,
1166 detach_aio_context, opaque);
1170 void blk_remove_aio_context_notifier(BlockBackend *blk,
1171 void (*attached_aio_context)(AioContext *,
1173 void (*detach_aio_context)(void *),
1177 bdrv_remove_aio_context_notifier(blk->bs, attached_aio_context,
1178 detach_aio_context, opaque);
1182 void blk_add_remove_bs_notifier(BlockBackend *blk, Notifier *notify)
1184 notifier_list_add(&blk->remove_bs_notifiers, notify);
1187 void blk_add_insert_bs_notifier(BlockBackend *blk, Notifier *notify)
1189 notifier_list_add(&blk->insert_bs_notifiers, notify);
1192 void blk_io_plug(BlockBackend *blk)
1195 bdrv_io_plug(blk->bs);
1199 void blk_io_unplug(BlockBackend *blk)
1202 bdrv_io_unplug(blk->bs);
1206 BlockAcctStats *blk_get_stats(BlockBackend *blk)
1211 void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk,
1212 BlockCompletionFunc *cb, void *opaque)
1214 return qemu_aio_get(aiocb_info, blk_bs(blk), cb, opaque);
1217 int coroutine_fn blk_co_write_zeroes(BlockBackend *blk, int64_t sector_num,
1218 int nb_sectors, BdrvRequestFlags flags)
1220 int ret = blk_check_request(blk, sector_num, nb_sectors);
1225 return bdrv_co_write_zeroes(blk->bs, sector_num, nb_sectors, flags);
1228 int blk_write_compressed(BlockBackend *blk, int64_t sector_num,
1229 const uint8_t *buf, int nb_sectors)
1231 int ret = blk_check_request(blk, sector_num, nb_sectors);
1236 return bdrv_write_compressed(blk->bs, sector_num, buf, nb_sectors);
1239 int blk_truncate(BlockBackend *blk, int64_t offset)
1241 if (!blk_is_available(blk)) {
1245 return bdrv_truncate(blk->bs, offset);
1248 int blk_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors)
1250 int ret = blk_check_request(blk, sector_num, nb_sectors);
1255 return bdrv_discard(blk->bs, sector_num, nb_sectors);
1258 int blk_save_vmstate(BlockBackend *blk, const uint8_t *buf,
1259 int64_t pos, int size)
1261 if (!blk_is_available(blk)) {
1265 return bdrv_save_vmstate(blk->bs, buf, pos, size);
1268 int blk_load_vmstate(BlockBackend *blk, uint8_t *buf, int64_t pos, int size)
1270 if (!blk_is_available(blk)) {
1274 return bdrv_load_vmstate(blk->bs, buf, pos, size);
1277 int blk_probe_blocksizes(BlockBackend *blk, BlockSizes *bsz)
1279 if (!blk_is_available(blk)) {
1283 return bdrv_probe_blocksizes(blk->bs, bsz);
1286 int blk_probe_geometry(BlockBackend *blk, HDGeometry *geo)
1288 if (!blk_is_available(blk)) {
1292 return bdrv_probe_geometry(blk->bs, geo);
1296 * Updates the BlockBackendRootState object with data from the currently
1297 * attached BlockDriverState.
1299 void blk_update_root_state(BlockBackend *blk)
1303 blk->root_state.open_flags = blk->bs->open_flags;
1304 blk->root_state.read_only = blk->bs->read_only;
1305 blk->root_state.detect_zeroes = blk->bs->detect_zeroes;
1307 if (blk->root_state.throttle_group) {
1308 g_free(blk->root_state.throttle_group);
1309 throttle_group_unref(blk->root_state.throttle_state);
1311 if (blk->bs->throttle_state) {
1312 const char *name = throttle_group_get_name(blk->bs);
1313 blk->root_state.throttle_group = g_strdup(name);
1314 blk->root_state.throttle_state = throttle_group_incref(name);
1316 blk->root_state.throttle_group = NULL;
1317 blk->root_state.throttle_state = NULL;
1322 * Applies the information in the root state to the given BlockDriverState. This
1323 * does not include the flags which have to be specified for bdrv_open(), use
1324 * blk_get_open_flags_from_root_state() to inquire them.
1326 void blk_apply_root_state(BlockBackend *blk, BlockDriverState *bs)
1328 bs->detect_zeroes = blk->root_state.detect_zeroes;
1329 if (blk->root_state.throttle_group) {
1330 bdrv_io_limits_enable(bs, blk->root_state.throttle_group);
1335 * Returns the flags to be used for bdrv_open() of a BlockDriverState which is
1336 * supposed to inherit the root state.
1338 int blk_get_open_flags_from_root_state(BlockBackend *blk)
1342 bs_flags = blk->root_state.read_only ? 0 : BDRV_O_RDWR;
1343 bs_flags |= blk->root_state.open_flags & ~BDRV_O_RDWR;
1348 BlockBackendRootState *blk_get_root_state(BlockBackend *blk)
1350 return &blk->root_state;
1353 int blk_commit_all(void)
1355 BlockBackend *blk = NULL;
1357 while ((blk = blk_all_next(blk)) != NULL) {
1358 AioContext *aio_context = blk_get_aio_context(blk);
1360 aio_context_acquire(aio_context);
1361 if (blk_is_inserted(blk) && blk->bs->backing) {
1362 int ret = bdrv_commit(blk->bs);
1364 aio_context_release(aio_context);
1368 aio_context_release(aio_context);
1373 int blk_flush_all(void)
1375 BlockBackend *blk = NULL;
1378 while ((blk = blk_all_next(blk)) != NULL) {
1379 AioContext *aio_context = blk_get_aio_context(blk);
1382 aio_context_acquire(aio_context);
1383 if (blk_is_inserted(blk)) {
1384 ret = blk_flush(blk);
1385 if (ret < 0 && !result) {
1389 aio_context_release(aio_context);