| /* |
| * QEMU Block backends |
| * |
| * Copyright (C) 2014-2016 Red Hat, Inc. |
| * |
| * Authors: |
| * Markus Armbruster <armbru@redhat.com>, |
| * |
| * This work is licensed under the terms of the GNU LGPL, version 2.1 |
| * or later. See the COPYING.LIB file in the top-level directory. |
| */ |
| |
| #include "qemu/osdep.h" |
| #include "sysemu/block-backend.h" |
| #include "block/block_int.h" |
| #include "block/blockjob.h" |
| #include "block/throttle-groups.h" |
| #include "hw/qdev-core.h" |
| #include "sysemu/blockdev.h" |
| #include "sysemu/runstate.h" |
| #include "qapi/error.h" |
| #include "qapi/qapi-events-block.h" |
| #include "qemu/id.h" |
| #include "qemu/main-loop.h" |
| #include "qemu/option.h" |
| #include "trace.h" |
| #include "migration/misc.h" |
| |
| /* Number of coroutines to reserve per attached device model */ |
| #define COROUTINE_POOL_RESERVATION 64 |
| |
| #define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */ |
| |
| static AioContext *blk_aiocb_get_aio_context(BlockAIOCB *acb); |
| |
| typedef struct BlockBackendAioNotifier { |
| void (*attached_aio_context)(AioContext *new_context, void *opaque); |
| void (*detach_aio_context)(void *opaque); |
| void *opaque; |
| QLIST_ENTRY(BlockBackendAioNotifier) list; |
| } BlockBackendAioNotifier; |
| |
| struct BlockBackend { |
| char *name; |
| int refcnt; |
| BdrvChild *root; |
| AioContext *ctx; |
| DriveInfo *legacy_dinfo; /* null unless created by drive_new() */ |
| QTAILQ_ENTRY(BlockBackend) link; /* for block_backends */ |
| QTAILQ_ENTRY(BlockBackend) monitor_link; /* for monitor_block_backends */ |
| BlockBackendPublic public; |
| |
| DeviceState *dev; /* attached device model, if any */ |
| const BlockDevOps *dev_ops; |
| void *dev_opaque; |
| |
| /* the block size for which the guest device expects atomicity */ |
| int guest_block_size; |
| |
| /* If the BDS tree is removed, some of its options are stored here (which |
| * can be used to restore those options in the new BDS on insert) */ |
| BlockBackendRootState root_state; |
| |
| bool enable_write_cache; |
| |
| /* I/O stats (display with "info blockstats"). */ |
| BlockAcctStats stats; |
| |
| BlockdevOnError on_read_error, on_write_error; |
| bool iostatus_enabled; |
| BlockDeviceIoStatus iostatus; |
| |
| uint64_t perm; |
| uint64_t shared_perm; |
| bool disable_perm; |
| |
| bool allow_aio_context_change; |
| bool allow_write_beyond_eof; |
| |
| NotifierList remove_bs_notifiers, insert_bs_notifiers; |
| QLIST_HEAD(, BlockBackendAioNotifier) aio_notifiers; |
| |
| int quiesce_counter; |
| CoQueue queued_requests; |
| bool disable_request_queuing; |
| |
| VMChangeStateEntry *vmsh; |
| bool force_allow_inactivate; |
| |
| /* Number of in-flight aio requests. BlockDriverState also counts |
| * in-flight requests but aio requests can exist even when blk->root is |
| * NULL, so we cannot rely on its counter for that case. |
| * Accessed with atomic ops. |
| */ |
| unsigned int in_flight; |
| }; |
| |
| typedef struct BlockBackendAIOCB { |
| BlockAIOCB common; |
| BlockBackend *blk; |
| int ret; |
| } BlockBackendAIOCB; |
| |
| static const AIOCBInfo block_backend_aiocb_info = { |
| .get_aio_context = blk_aiocb_get_aio_context, |
| .aiocb_size = sizeof(BlockBackendAIOCB), |
| }; |
| |
| static void drive_info_del(DriveInfo *dinfo); |
| static BlockBackend *bdrv_first_blk(BlockDriverState *bs); |
| |
| /* All BlockBackends */ |
| static QTAILQ_HEAD(, BlockBackend) block_backends = |
| QTAILQ_HEAD_INITIALIZER(block_backends); |
| |
| /* All BlockBackends referenced by the monitor and which are iterated through by |
| * blk_next() */ |
| static QTAILQ_HEAD(, BlockBackend) monitor_block_backends = |
| QTAILQ_HEAD_INITIALIZER(monitor_block_backends); |
| |
| static void blk_root_inherit_options(int *child_flags, QDict *child_options, |
| int parent_flags, QDict *parent_options) |
| { |
| /* We're not supposed to call this function for root nodes */ |
| abort(); |
| } |
| static void blk_root_drained_begin(BdrvChild *child); |
| static bool blk_root_drained_poll(BdrvChild *child); |
| static void blk_root_drained_end(BdrvChild *child, int *drained_end_counter); |
| |
| static void blk_root_change_media(BdrvChild *child, bool load); |
| static void blk_root_resize(BdrvChild *child); |
| |
| static bool blk_root_can_set_aio_ctx(BdrvChild *child, AioContext *ctx, |
| GSList **ignore, Error **errp); |
| static void blk_root_set_aio_ctx(BdrvChild *child, AioContext *ctx, |
| GSList **ignore); |
| |
| static char *blk_root_get_parent_desc(BdrvChild *child) |
| { |
| BlockBackend *blk = child->opaque; |
| char *dev_id; |
| |
| if (blk->name) { |
| return g_strdup(blk->name); |
| } |
| |
| dev_id = blk_get_attached_dev_id(blk); |
| if (*dev_id) { |
| return dev_id; |
| } else { |
| /* TODO Callback into the BB owner for something more detailed */ |
| g_free(dev_id); |
| return g_strdup("a block device"); |
| } |
| } |
| |
| static const char *blk_root_get_name(BdrvChild *child) |
| { |
| return blk_name(child->opaque); |
| } |
| |
| static void blk_vm_state_changed(void *opaque, int running, RunState state) |
| { |
| Error *local_err = NULL; |
| BlockBackend *blk = opaque; |
| |
| if (state == RUN_STATE_INMIGRATE) { |
| return; |
| } |
| |
| qemu_del_vm_change_state_handler(blk->vmsh); |
| blk->vmsh = NULL; |
| blk_set_perm(blk, blk->perm, blk->shared_perm, &local_err); |
| if (local_err) { |
| error_report_err(local_err); |
| } |
| } |
| |
| /* |
| * Notifies the user of the BlockBackend that migration has completed. qdev |
| * devices can tighten their permissions in response (specifically revoke |
| * shared write permissions that we needed for storage migration). |
| * |
| * If an error is returned, the VM cannot be allowed to be resumed. |
| */ |
| static void blk_root_activate(BdrvChild *child, Error **errp) |
| { |
| BlockBackend *blk = child->opaque; |
| Error *local_err = NULL; |
| |
| if (!blk->disable_perm) { |
| return; |
| } |
| |
| blk->disable_perm = false; |
| |
| blk_set_perm(blk, blk->perm, BLK_PERM_ALL, &local_err); |
| if (local_err) { |
| error_propagate(errp, local_err); |
| blk->disable_perm = true; |
| return; |
| } |
| |
| if (runstate_check(RUN_STATE_INMIGRATE)) { |
| /* Activation can happen when migration process is still active, for |
| * example when nbd_server_add is called during non-shared storage |
| * migration. Defer the shared_perm update to migration completion. */ |
| if (!blk->vmsh) { |
| blk->vmsh = qemu_add_vm_change_state_handler(blk_vm_state_changed, |
| blk); |
| } |
| return; |
| } |
| |
| blk_set_perm(blk, blk->perm, blk->shared_perm, &local_err); |
| if (local_err) { |
| error_propagate(errp, local_err); |
| blk->disable_perm = true; |
| return; |
| } |
| } |
| |
| void blk_set_force_allow_inactivate(BlockBackend *blk) |
| { |
| blk->force_allow_inactivate = true; |
| } |
| |
| static bool blk_can_inactivate(BlockBackend *blk) |
| { |
| /* If it is a guest device, inactivate is ok. */ |
| if (blk->dev || blk_name(blk)[0]) { |
| return true; |
| } |
| |
| /* Inactivating means no more writes to the image can be done, |
| * even if those writes would be changes invisible to the |
| * guest. For block job BBs that satisfy this, we can just allow |
| * it. This is the case for mirror job source, which is required |
| * by libvirt non-shared block migration. */ |
| if (!(blk->perm & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED))) { |
| return true; |
| } |
| |
| return blk->force_allow_inactivate; |
| } |
| |
| static int blk_root_inactivate(BdrvChild *child) |
| { |
| BlockBackend *blk = child->opaque; |
| |
| if (blk->disable_perm) { |
| return 0; |
| } |
| |
| if (!blk_can_inactivate(blk)) { |
| return -EPERM; |
| } |
| |
| blk->disable_perm = true; |
| if (blk->root) { |
| bdrv_child_try_set_perm(blk->root, 0, BLK_PERM_ALL, &error_abort); |
| } |
| |
| return 0; |
| } |
| |
| static void blk_root_attach(BdrvChild *child) |
| { |
| BlockBackend *blk = child->opaque; |
| BlockBackendAioNotifier *notifier; |
| |
| trace_blk_root_attach(child, blk, child->bs); |
| |
| QLIST_FOREACH(notifier, &blk->aio_notifiers, list) { |
| bdrv_add_aio_context_notifier(child->bs, |
| notifier->attached_aio_context, |
| notifier->detach_aio_context, |
| notifier->opaque); |
| } |
| } |
| |
| static void blk_root_detach(BdrvChild *child) |
| { |
| BlockBackend *blk = child->opaque; |
| BlockBackendAioNotifier *notifier; |
| |
| trace_blk_root_detach(child, blk, child->bs); |
| |
| QLIST_FOREACH(notifier, &blk->aio_notifiers, list) { |
| bdrv_remove_aio_context_notifier(child->bs, |
| notifier->attached_aio_context, |
| notifier->detach_aio_context, |
| notifier->opaque); |
| } |
| } |
| |
| static const BdrvChildRole child_root = { |
| .inherit_options = blk_root_inherit_options, |
| |
| .change_media = blk_root_change_media, |
| .resize = blk_root_resize, |
| .get_name = blk_root_get_name, |
| .get_parent_desc = blk_root_get_parent_desc, |
| |
| .drained_begin = blk_root_drained_begin, |
| .drained_poll = blk_root_drained_poll, |
| .drained_end = blk_root_drained_end, |
| |
| .activate = blk_root_activate, |
| .inactivate = blk_root_inactivate, |
| |
| .attach = blk_root_attach, |
| .detach = blk_root_detach, |
| |
| .can_set_aio_ctx = blk_root_can_set_aio_ctx, |
| .set_aio_ctx = blk_root_set_aio_ctx, |
| }; |
| |
| /* |
| * Create a new BlockBackend with a reference count of one. |
| * |
| * @perm is a bitmasks of BLK_PERM_* constants which describes the permissions |
| * to request for a block driver node that is attached to this BlockBackend. |
| * @shared_perm is a bitmask which describes which permissions may be granted |
| * to other users of the attached node. |
| * Both sets of permissions can be changed later using blk_set_perm(). |
| * |
| * Return the new BlockBackend on success, null on failure. |
| */ |
| BlockBackend *blk_new(AioContext *ctx, uint64_t perm, uint64_t shared_perm) |
| { |
| BlockBackend *blk; |
| |
| blk = g_new0(BlockBackend, 1); |
| blk->refcnt = 1; |
| blk->ctx = ctx; |
| blk->perm = perm; |
| blk->shared_perm = shared_perm; |
| blk_set_enable_write_cache(blk, true); |
| |
| blk->on_read_error = BLOCKDEV_ON_ERROR_REPORT; |
| blk->on_write_error = BLOCKDEV_ON_ERROR_ENOSPC; |
| |
| block_acct_init(&blk->stats); |
| |
| qemu_co_queue_init(&blk->queued_requests); |
| notifier_list_init(&blk->remove_bs_notifiers); |
| notifier_list_init(&blk->insert_bs_notifiers); |
| QLIST_INIT(&blk->aio_notifiers); |
| |
| QTAILQ_INSERT_TAIL(&block_backends, blk, link); |
| return blk; |
| } |
| |
| /* |
| * Creates a new BlockBackend, opens a new BlockDriverState, and connects both. |
| * The new BlockBackend is in the main AioContext. |
| * |
| * Just as with bdrv_open(), after having called this function the reference to |
| * @options belongs to the block layer (even on failure). |
| * |
| * TODO: Remove @filename and @flags; it should be possible to specify a whole |
| * BDS tree just by specifying the @options QDict (or @reference, |
| * alternatively). At the time of adding this function, this is not possible, |
| * though, so callers of this function have to be able to specify @filename and |
| * @flags. |
| */ |
| BlockBackend *blk_new_open(const char *filename, const char *reference, |
| QDict *options, int flags, Error **errp) |
| { |
| BlockBackend *blk; |
| BlockDriverState *bs; |
| uint64_t perm = 0; |
| |
| /* blk_new_open() is mainly used in .bdrv_create implementations and the |
| * tools where sharing isn't a concern because the BDS stays private, so we |
| * just request permission according to the flags. |
| * |
| * The exceptions are xen_disk and blockdev_init(); in these cases, the |
| * caller of blk_new_open() doesn't make use of the permissions, but they |
| * shouldn't hurt either. We can still share everything here because the |
| * guest devices will add their own blockers if they can't share. */ |
| if ((flags & BDRV_O_NO_IO) == 0) { |
| perm |= BLK_PERM_CONSISTENT_READ; |
| if (flags & BDRV_O_RDWR) { |
| perm |= BLK_PERM_WRITE; |
| } |
| } |
| if (flags & BDRV_O_RESIZE) { |
| perm |= BLK_PERM_RESIZE; |
| } |
| |
| blk = blk_new(qemu_get_aio_context(), perm, BLK_PERM_ALL); |
| bs = bdrv_open(filename, reference, options, flags, errp); |
| if (!bs) { |
| blk_unref(blk); |
| return NULL; |
| } |
| |
| blk->root = bdrv_root_attach_child(bs, "root", &child_root, blk->ctx, |
| perm, BLK_PERM_ALL, blk, errp); |
| if (!blk->root) { |
| blk_unref(blk); |
| return NULL; |
| } |
| |
| return blk; |
| } |
| |
| static void blk_delete(BlockBackend *blk) |
| { |
| assert(!blk->refcnt); |
| assert(!blk->name); |
| assert(!blk->dev); |
| if (blk->public.throttle_group_member.throttle_state) { |
| blk_io_limits_disable(blk); |
| } |
| if (blk->root) { |
| blk_remove_bs(blk); |
| } |
| if (blk->vmsh) { |
| qemu_del_vm_change_state_handler(blk->vmsh); |
| blk->vmsh = NULL; |
| } |
| assert(QLIST_EMPTY(&blk->remove_bs_notifiers.notifiers)); |
| assert(QLIST_EMPTY(&blk->insert_bs_notifiers.notifiers)); |
| assert(QLIST_EMPTY(&blk->aio_notifiers)); |
| QTAILQ_REMOVE(&block_backends, blk, link); |
| drive_info_del(blk->legacy_dinfo); |
| block_acct_cleanup(&blk->stats); |
| g_free(blk); |
| } |
| |
| static void drive_info_del(DriveInfo *dinfo) |
| { |
| if (!dinfo) { |
| return; |
| } |
| qemu_opts_del(dinfo->opts); |
| g_free(dinfo); |
| } |
| |
| int blk_get_refcnt(BlockBackend *blk) |
| { |
| return blk ? blk->refcnt : 0; |
| } |
| |
| /* |
| * Increment @blk's reference count. |
| * @blk must not be null. |
| */ |
| void blk_ref(BlockBackend *blk) |
| { |
| assert(blk->refcnt > 0); |
| blk->refcnt++; |
| } |
| |
| /* |
| * Decrement @blk's reference count. |
| * If this drops it to zero, destroy @blk. |
| * For convenience, do nothing if @blk is null. |
| */ |
| void blk_unref(BlockBackend *blk) |
| { |
| if (blk) { |
| assert(blk->refcnt > 0); |
| if (blk->refcnt > 1) { |
| blk->refcnt--; |
| } else { |
| blk_drain(blk); |
| /* blk_drain() cannot resurrect blk, nobody held a reference */ |
| assert(blk->refcnt == 1); |
| blk->refcnt = 0; |
| blk_delete(blk); |
| } |
| } |
| } |
| |
| /* |
| * Behaves similarly to blk_next() but iterates over all BlockBackends, even the |
| * ones which are hidden (i.e. are not referenced by the monitor). |
| */ |
| BlockBackend *blk_all_next(BlockBackend *blk) |
| { |
| return blk ? QTAILQ_NEXT(blk, link) |
| : QTAILQ_FIRST(&block_backends); |
| } |
| |
| void blk_remove_all_bs(void) |
| { |
| BlockBackend *blk = NULL; |
| |
| while ((blk = blk_all_next(blk)) != NULL) { |
| AioContext *ctx = blk_get_aio_context(blk); |
| |
| aio_context_acquire(ctx); |
| if (blk->root) { |
| blk_remove_bs(blk); |
| } |
| aio_context_release(ctx); |
| } |
| } |
| |
| /* |
| * Return the monitor-owned BlockBackend after @blk. |
| * If @blk is null, return the first one. |
| * Else, return @blk's next sibling, which may be null. |
| * |
| * To iterate over all BlockBackends, do |
| * for (blk = blk_next(NULL); blk; blk = blk_next(blk)) { |
| * ... |
| * } |
| */ |
| BlockBackend *blk_next(BlockBackend *blk) |
| { |
| return blk ? QTAILQ_NEXT(blk, monitor_link) |
| : QTAILQ_FIRST(&monitor_block_backends); |
| } |
| |
| /* Iterates over all top-level BlockDriverStates, i.e. BDSs that are owned by |
| * the monitor or attached to a BlockBackend */ |
| BlockDriverState *bdrv_next(BdrvNextIterator *it) |
| { |
| BlockDriverState *bs, *old_bs; |
| |
| /* Must be called from the main loop */ |
| assert(qemu_get_current_aio_context() == qemu_get_aio_context()); |
| |
| /* First, return all root nodes of BlockBackends. In order to avoid |
| * returning a BDS twice when multiple BBs refer to it, we only return it |
| * if the BB is the first one in the parent list of the BDS. */ |
| if (it->phase == BDRV_NEXT_BACKEND_ROOTS) { |
| BlockBackend *old_blk = it->blk; |
| |
| old_bs = old_blk ? blk_bs(old_blk) : NULL; |
| |
| do { |
| it->blk = blk_all_next(it->blk); |
| bs = it->blk ? blk_bs(it->blk) : NULL; |
| } while (it->blk && (bs == NULL || bdrv_first_blk(bs) != it->blk)); |
| |
| if (it->blk) { |
| blk_ref(it->blk); |
| } |
| blk_unref(old_blk); |
| |
| if (bs) { |
| bdrv_ref(bs); |
| bdrv_unref(old_bs); |
| return bs; |
| } |
| it->phase = BDRV_NEXT_MONITOR_OWNED; |
| } else { |
| old_bs = it->bs; |
| } |
| |
| /* Then return the monitor-owned BDSes without a BB attached. Ignore all |
| * BDSes that are attached to a BlockBackend here; they have been handled |
| * by the above block already */ |
| do { |
| it->bs = bdrv_next_monitor_owned(it->bs); |
| bs = it->bs; |
| } while (bs && bdrv_has_blk(bs)); |
| |
| if (bs) { |
| bdrv_ref(bs); |
| } |
| bdrv_unref(old_bs); |
| |
| return bs; |
| } |
| |
| static void bdrv_next_reset(BdrvNextIterator *it) |
| { |
| *it = (BdrvNextIterator) { |
| .phase = BDRV_NEXT_BACKEND_ROOTS, |
| }; |
| } |
| |
| BlockDriverState *bdrv_first(BdrvNextIterator *it) |
| { |
| bdrv_next_reset(it); |
| return bdrv_next(it); |
| } |
| |
| /* Must be called when aborting a bdrv_next() iteration before |
| * bdrv_next() returns NULL */ |
| void bdrv_next_cleanup(BdrvNextIterator *it) |
| { |
| /* Must be called from the main loop */ |
| assert(qemu_get_current_aio_context() == qemu_get_aio_context()); |
| |
| if (it->phase == BDRV_NEXT_BACKEND_ROOTS) { |
| if (it->blk) { |
| bdrv_unref(blk_bs(it->blk)); |
| blk_unref(it->blk); |
| } |
| } else { |
| bdrv_unref(it->bs); |
| } |
| |
| bdrv_next_reset(it); |
| } |
| |
| /* |
| * Add a BlockBackend into the list of backends referenced by the monitor, with |
| * the given @name acting as the handle for the monitor. |
| * Strictly for use by blockdev.c. |
| * |
| * @name must not be null or empty. |
| * |
| * Returns true on success and false on failure. In the latter case, an Error |
| * object is returned through @errp. |
| */ |
| bool monitor_add_blk(BlockBackend *blk, const char *name, Error **errp) |
| { |
| assert(!blk->name); |
| assert(name && name[0]); |
| |
| if (!id_wellformed(name)) { |
| error_setg(errp, "Invalid device name"); |
| return false; |
| } |
| if (blk_by_name(name)) { |
| error_setg(errp, "Device with id '%s' already exists", name); |
| return false; |
| } |
| if (bdrv_find_node(name)) { |
| error_setg(errp, |
| "Device name '%s' conflicts with an existing node name", |
| name); |
| return false; |
| } |
| |
| blk->name = g_strdup(name); |
| QTAILQ_INSERT_TAIL(&monitor_block_backends, blk, monitor_link); |
| return true; |
| } |
| |
| /* |
| * Remove a BlockBackend from the list of backends referenced by the monitor. |
| * Strictly for use by blockdev.c. |
| */ |
| void monitor_remove_blk(BlockBackend *blk) |
| { |
| if (!blk->name) { |
| return; |
| } |
| |
| QTAILQ_REMOVE(&monitor_block_backends, blk, monitor_link); |
| g_free(blk->name); |
| blk->name = NULL; |
| } |
| |
| /* |
| * Return @blk's name, a non-null string. |
| * Returns an empty string iff @blk is not referenced by the monitor. |
| */ |
| const char *blk_name(const BlockBackend *blk) |
| { |
| return blk->name ?: ""; |
| } |
| |
| /* |
| * Return the BlockBackend with name @name if it exists, else null. |
| * @name must not be null. |
| */ |
| BlockBackend *blk_by_name(const char *name) |
| { |
| BlockBackend *blk = NULL; |
| |
| assert(name); |
| while ((blk = blk_next(blk)) != NULL) { |
| if (!strcmp(name, blk->name)) { |
| return blk; |
| } |
| } |
| return NULL; |
| } |
| |
| /* |
| * Return the BlockDriverState attached to @blk if any, else null. |
| */ |
| BlockDriverState *blk_bs(BlockBackend *blk) |
| { |
| return blk->root ? blk->root->bs : NULL; |
| } |
| |
| static BlockBackend *bdrv_first_blk(BlockDriverState *bs) |
| { |
| BdrvChild *child; |
| QLIST_FOREACH(child, &bs->parents, next_parent) { |
| if (child->role == &child_root) { |
| return child->opaque; |
| } |
| } |
| |
| return NULL; |
| } |
| |
| /* |
| * Returns true if @bs has an associated BlockBackend. |
| */ |
| bool bdrv_has_blk(BlockDriverState *bs) |
| { |
| return bdrv_first_blk(bs) != NULL; |
| } |
| |
| /* |
| * Returns true if @bs has only BlockBackends as parents. |
| */ |
| bool bdrv_is_root_node(BlockDriverState *bs) |
| { |
| BdrvChild *c; |
| |
| QLIST_FOREACH(c, &bs->parents, next_parent) { |
| if (c->role != &child_root) { |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| /* |
| * Return @blk's DriveInfo if any, else null. |
| */ |
| DriveInfo *blk_legacy_dinfo(BlockBackend *blk) |
| { |
| return blk->legacy_dinfo; |
| } |
| |
| /* |
| * Set @blk's DriveInfo to @dinfo, and return it. |
| * @blk must not have a DriveInfo set already. |
| * No other BlockBackend may have the same DriveInfo set. |
| */ |
| DriveInfo *blk_set_legacy_dinfo(BlockBackend *blk, DriveInfo *dinfo) |
| { |
| assert(!blk->legacy_dinfo); |
| return blk->legacy_dinfo = dinfo; |
| } |
| |
| /* |
| * Return the BlockBackend with DriveInfo @dinfo. |
| * It must exist. |
| */ |
| BlockBackend *blk_by_legacy_dinfo(DriveInfo *dinfo) |
| { |
| BlockBackend *blk = NULL; |
| |
| while ((blk = blk_next(blk)) != NULL) { |
| if (blk->legacy_dinfo == dinfo) { |
| return blk; |
| } |
| } |
| abort(); |
| } |
| |
| /* |
| * Returns a pointer to the publicly accessible fields of @blk. |
| */ |
| BlockBackendPublic *blk_get_public(BlockBackend *blk) |
| { |
| return &blk->public; |
| } |
| |
| /* |
| * Returns a BlockBackend given the associated @public fields. |
| */ |
| BlockBackend *blk_by_public(BlockBackendPublic *public) |
| { |
| return container_of(public, BlockBackend, public); |
| } |
| |
| /* |
| * Disassociates the currently associated BlockDriverState from @blk. |
| */ |
| void blk_remove_bs(BlockBackend *blk) |
| { |
| ThrottleGroupMember *tgm = &blk->public.throttle_group_member; |
| BlockDriverState *bs; |
| |
| notifier_list_notify(&blk->remove_bs_notifiers, blk); |
| if (tgm->throttle_state) { |
| bs = blk_bs(blk); |
| bdrv_drained_begin(bs); |
| throttle_group_detach_aio_context(tgm); |
| throttle_group_attach_aio_context(tgm, qemu_get_aio_context()); |
| bdrv_drained_end(bs); |
| } |
| |
| blk_update_root_state(blk); |
| |
| /* bdrv_root_unref_child() will cause blk->root to become stale and may |
| * switch to a completion coroutine later on. Let's drain all I/O here |
| * to avoid that and a potential QEMU crash. |
| */ |
| blk_drain(blk); |
| bdrv_root_unref_child(blk->root); |
| blk->root = NULL; |
| } |
| |
| /* |
| * Associates a new BlockDriverState with @blk. |
| */ |
| int blk_insert_bs(BlockBackend *blk, BlockDriverState *bs, Error **errp) |
| { |
| ThrottleGroupMember *tgm = &blk->public.throttle_group_member; |
| bdrv_ref(bs); |
| blk->root = bdrv_root_attach_child(bs, "root", &child_root, blk->ctx, |
| blk->perm, blk->shared_perm, blk, errp); |
| if (blk->root == NULL) { |
| return -EPERM; |
| } |
| |
| notifier_list_notify(&blk->insert_bs_notifiers, blk); |
| if (tgm->throttle_state) { |
| throttle_group_detach_aio_context(tgm); |
| throttle_group_attach_aio_context(tgm, bdrv_get_aio_context(bs)); |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Sets the permission bitmasks that the user of the BlockBackend needs. |
| */ |
| int blk_set_perm(BlockBackend *blk, uint64_t perm, uint64_t shared_perm, |
| Error **errp) |
| { |
| int ret; |
| |
| if (blk->root && !blk->disable_perm) { |
| ret = bdrv_child_try_set_perm(blk->root, perm, shared_perm, errp); |
| if (ret < 0) { |
| return ret; |
| } |
| } |
| |
| blk->perm = perm; |
| blk->shared_perm = shared_perm; |
| |
| return 0; |
| } |
| |
| void blk_get_perm(BlockBackend *blk, uint64_t *perm, uint64_t *shared_perm) |
| { |
| *perm = blk->perm; |
| *shared_perm = blk->shared_perm; |
| } |
| |
| /* |
| * Attach device model @dev to @blk. |
| * Return 0 on success, -EBUSY when a device model is attached already. |
| */ |
| int blk_attach_dev(BlockBackend *blk, DeviceState *dev) |
| { |
| if (blk->dev) { |
| return -EBUSY; |
| } |
| |
| /* While migration is still incoming, we don't need to apply the |
| * permissions of guest device BlockBackends. We might still have a block |
| * job or NBD server writing to the image for storage migration. */ |
| if (runstate_check(RUN_STATE_INMIGRATE)) { |
| blk->disable_perm = true; |
| } |
| |
| blk_ref(blk); |
| blk->dev = dev; |
| blk_iostatus_reset(blk); |
| |
| return 0; |
| } |
| |
| /* |
| * Detach device model @dev from @blk. |
| * @dev must be currently attached to @blk. |
| */ |
| void blk_detach_dev(BlockBackend *blk, DeviceState *dev) |
| { |
| assert(blk->dev == dev); |
| blk->dev = NULL; |
| blk->dev_ops = NULL; |
| blk->dev_opaque = NULL; |
| blk->guest_block_size = 512; |
| blk_set_perm(blk, 0, BLK_PERM_ALL, &error_abort); |
| blk_unref(blk); |
| } |
| |
| /* |
| * Return the device model attached to @blk if any, else null. |
| */ |
| DeviceState *blk_get_attached_dev(BlockBackend *blk) |
| { |
| return blk->dev; |
| } |
| |
| /* Return the qdev ID, or if no ID is assigned the QOM path, of the block |
| * device attached to the BlockBackend. */ |
| char *blk_get_attached_dev_id(BlockBackend *blk) |
| { |
| DeviceState *dev = blk->dev; |
| |
| if (!dev) { |
| return g_strdup(""); |
| } else if (dev->id) { |
| return g_strdup(dev->id); |
| } |
| |
| return object_get_canonical_path(OBJECT(dev)) ?: g_strdup(""); |
| } |
| |
| /* |
| * Return the BlockBackend which has the device model @dev attached if it |
| * exists, else null. |
| * |
| * @dev must not be null. |
| */ |
| BlockBackend *blk_by_dev(void *dev) |
| { |
| BlockBackend *blk = NULL; |
| |
| assert(dev != NULL); |
| while ((blk = blk_all_next(blk)) != NULL) { |
| if (blk->dev == dev) { |
| return blk; |
| } |
| } |
| return NULL; |
| } |
| |
| /* |
| * Set @blk's device model callbacks to @ops. |
| * @opaque is the opaque argument to pass to the callbacks. |
| * This is for use by device models. |
| */ |
| void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops, |
| void *opaque) |
| { |
| blk->dev_ops = ops; |
| blk->dev_opaque = opaque; |
| |
| /* Are we currently quiesced? Should we enforce this right now? */ |
| if (blk->quiesce_counter && ops->drained_begin) { |
| ops->drained_begin(opaque); |
| } |
| } |
| |
| /* |
| * Notify @blk's attached device model of media change. |
| * |
| * If @load is true, notify of media load. This action can fail, meaning that |
| * the medium cannot be loaded. @errp is set then. |
| * |
| * If @load is false, notify of media eject. This can never fail. |
| * |
| * Also send DEVICE_TRAY_MOVED events as appropriate. |
| */ |
| void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error **errp) |
| { |
| if (blk->dev_ops && blk->dev_ops->change_media_cb) { |
| bool tray_was_open, tray_is_open; |
| Error *local_err = NULL; |
| |
| tray_was_open = blk_dev_is_tray_open(blk); |
| blk->dev_ops->change_media_cb(blk->dev_opaque, load, &local_err); |
| if (local_err) { |
| assert(load == true); |
| error_propagate(errp, local_err); |
| return; |
| } |
| tray_is_open = blk_dev_is_tray_open(blk); |
| |
| if (tray_was_open != tray_is_open) { |
| char *id = blk_get_attached_dev_id(blk); |
| qapi_event_send_device_tray_moved(blk_name(blk), id, tray_is_open); |
| g_free(id); |
| } |
| } |
| } |
| |
| static void blk_root_change_media(BdrvChild *child, bool load) |
| { |
| blk_dev_change_media_cb(child->opaque, load, NULL); |
| } |
| |
| /* |
| * Does @blk's attached device model have removable media? |
| * %true if no device model is attached. |
| */ |
| bool blk_dev_has_removable_media(BlockBackend *blk) |
| { |
| return !blk->dev || (blk->dev_ops && blk->dev_ops->change_media_cb); |
| } |
| |
| /* |
| * Does @blk's attached device model have a tray? |
| */ |
| bool blk_dev_has_tray(BlockBackend *blk) |
| { |
| return blk->dev_ops && blk->dev_ops->is_tray_open; |
| } |
| |
| /* |
| * Notify @blk's attached device model of a media eject request. |
| * If @force is true, the medium is about to be yanked out forcefully. |
| */ |
| void blk_dev_eject_request(BlockBackend *blk, bool force) |
| { |
| if (blk->dev_ops && blk->dev_ops->eject_request_cb) { |
| blk->dev_ops->eject_request_cb(blk->dev_opaque, force); |
| } |
| } |
| |
| /* |
| * Does @blk's attached device model have a tray, and is it open? |
| */ |
| bool blk_dev_is_tray_open(BlockBackend *blk) |
| { |
| if (blk_dev_has_tray(blk)) { |
| return blk->dev_ops->is_tray_open(blk->dev_opaque); |
| } |
| return false; |
| } |
| |
| /* |
| * Does @blk's attached device model have the medium locked? |
| * %false if the device model has no such lock. |
| */ |
| bool blk_dev_is_medium_locked(BlockBackend *blk) |
| { |
| if (blk->dev_ops && blk->dev_ops->is_medium_locked) { |
| return blk->dev_ops->is_medium_locked(blk->dev_opaque); |
| } |
| return false; |
| } |
| |
| /* |
| * Notify @blk's attached device model of a backend size change. |
| */ |
| static void blk_root_resize(BdrvChild *child) |
| { |
| BlockBackend *blk = child->opaque; |
| |
| if (blk->dev_ops && blk->dev_ops->resize_cb) { |
| blk->dev_ops->resize_cb(blk->dev_opaque); |
| } |
| } |
| |
| void blk_iostatus_enable(BlockBackend *blk) |
| { |
| blk->iostatus_enabled = true; |
| blk->iostatus = BLOCK_DEVICE_IO_STATUS_OK; |
| } |
| |
| /* The I/O status is only enabled if the drive explicitly |
| * enables it _and_ the VM is configured to stop on errors */ |
| bool blk_iostatus_is_enabled(const BlockBackend *blk) |
| { |
| return (blk->iostatus_enabled && |
| (blk->on_write_error == BLOCKDEV_ON_ERROR_ENOSPC || |
| blk->on_write_error == BLOCKDEV_ON_ERROR_STOP || |
| blk->on_read_error == BLOCKDEV_ON_ERROR_STOP)); |
| } |
| |
| BlockDeviceIoStatus blk_iostatus(const BlockBackend *blk) |
| { |
| return blk->iostatus; |
| } |
| |
| void blk_iostatus_disable(BlockBackend *blk) |
| { |
| blk->iostatus_enabled = false; |
| } |
| |
| void blk_iostatus_reset(BlockBackend *blk) |
| { |
| if (blk_iostatus_is_enabled(blk)) { |
| blk->iostatus = BLOCK_DEVICE_IO_STATUS_OK; |
| } |
| } |
| |
| void blk_iostatus_set_err(BlockBackend *blk, int error) |
| { |
| assert(blk_iostatus_is_enabled(blk)); |
| if (blk->iostatus == BLOCK_DEVICE_IO_STATUS_OK) { |
| blk->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE : |
| BLOCK_DEVICE_IO_STATUS_FAILED; |
| } |
| } |
| |
| void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow) |
| { |
| blk->allow_write_beyond_eof = allow; |
| } |
| |
| void blk_set_allow_aio_context_change(BlockBackend *blk, bool allow) |
| { |
| blk->allow_aio_context_change = allow; |
| } |
| |
| void blk_set_disable_request_queuing(BlockBackend *blk, bool disable) |
| { |
| blk->disable_request_queuing = disable; |
| } |
| |
| static int blk_check_byte_request(BlockBackend *blk, int64_t offset, |
| size_t size) |
| { |
| int64_t len; |
| |
| if (size > INT_MAX) { |
| return -EIO; |
| } |
| |
| if (!blk_is_available(blk)) { |
| return -ENOMEDIUM; |
| } |
| |
| if (offset < 0) { |
| return -EIO; |
| } |
| |
| if (!blk->allow_write_beyond_eof) { |
| len = blk_getlength(blk); |
| if (len < 0) { |
| return len; |
| } |
| |
| if (offset > len || len - offset < size) { |
| return -EIO; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static void coroutine_fn blk_wait_while_drained(BlockBackend *blk) |
| { |
| if (blk->quiesce_counter && !blk->disable_request_queuing) { |
| qemu_co_queue_wait(&blk->queued_requests, NULL); |
| } |
| } |
| |
| int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset, |
| unsigned int bytes, QEMUIOVector *qiov, |
| BdrvRequestFlags flags) |
| { |
| int ret; |
| BlockDriverState *bs; |
| |
| blk_wait_while_drained(blk); |
| |
| /* Call blk_bs() only after waiting, the graph may have changed */ |
| bs = blk_bs(blk); |
| trace_blk_co_preadv(blk, bs, offset, bytes, flags); |
| |
| ret = blk_check_byte_request(blk, offset, bytes); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| bdrv_inc_in_flight(bs); |
| |
| /* throttling disk I/O */ |
| if (blk->public.throttle_group_member.throttle_state) { |
| throttle_group_co_io_limits_intercept(&blk->public.throttle_group_member, |
| bytes, false); |
| } |
| |
| ret = bdrv_co_preadv(blk->root, offset, bytes, qiov, flags); |
| bdrv_dec_in_flight(bs); |
| return ret; |
| } |
| |
| int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset, |
| unsigned int bytes, QEMUIOVector *qiov, |
| BdrvRequestFlags flags) |
| { |
| int ret; |
| BlockDriverState *bs; |
| |
| blk_wait_while_drained(blk); |
| |
| /* Call blk_bs() only after waiting, the graph may have changed */ |
| bs = blk_bs(blk); |
| trace_blk_co_pwritev(blk, bs, offset, bytes, flags); |
| |
| ret = blk_check_byte_request(blk, offset, bytes); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| bdrv_inc_in_flight(bs); |
| /* throttling disk I/O */ |
| if (blk->public.throttle_group_member.throttle_state) { |
| throttle_group_co_io_limits_intercept(&blk->public.throttle_group_member, |
| bytes, true); |
| } |
| |
| if (!blk->enable_write_cache) { |
| flags |= BDRV_REQ_FUA; |
| } |
| |
| ret = bdrv_co_pwritev(blk->root, offset, bytes, qiov, flags); |
| bdrv_dec_in_flight(bs); |
| return ret; |
| } |
| |
| typedef struct BlkRwCo { |
| BlockBackend *blk; |
| int64_t offset; |
| void *iobuf; |
| int ret; |
| BdrvRequestFlags flags; |
| } BlkRwCo; |
| |
| static void blk_read_entry(void *opaque) |
| { |
| BlkRwCo *rwco = opaque; |
| QEMUIOVector *qiov = rwco->iobuf; |
| |
| rwco->ret = blk_co_preadv(rwco->blk, rwco->offset, qiov->size, |
| qiov, rwco->flags); |
| aio_wait_kick(); |
| } |
| |
| static void blk_write_entry(void *opaque) |
| { |
| BlkRwCo *rwco = opaque; |
| QEMUIOVector *qiov = rwco->iobuf; |
| |
| rwco->ret = blk_co_pwritev(rwco->blk, rwco->offset, qiov->size, |
| qiov, rwco->flags); |
| aio_wait_kick(); |
| } |
| |
| static int blk_prw(BlockBackend *blk, int64_t offset, uint8_t *buf, |
| int64_t bytes, CoroutineEntry co_entry, |
| BdrvRequestFlags flags) |
| { |
| QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); |
| BlkRwCo rwco = { |
| .blk = blk, |
| .offset = offset, |
| .iobuf = &qiov, |
| .flags = flags, |
| .ret = NOT_DONE, |
| }; |
| |
| if (qemu_in_coroutine()) { |
| /* Fast-path if already in coroutine context */ |
| co_entry(&rwco); |
| } else { |
| Coroutine *co = qemu_coroutine_create(co_entry, &rwco); |
| bdrv_coroutine_enter(blk_bs(blk), co); |
| BDRV_POLL_WHILE(blk_bs(blk), rwco.ret == NOT_DONE); |
| } |
| |
| return rwco.ret; |
| } |
| |
| int blk_pwrite_zeroes(BlockBackend *blk, int64_t offset, |
| int bytes, BdrvRequestFlags flags) |
| { |
| return blk_prw(blk, offset, NULL, bytes, blk_write_entry, |
| flags | BDRV_REQ_ZERO_WRITE); |
| } |
| |
| int blk_make_zero(BlockBackend *blk, BdrvRequestFlags flags) |
| { |
| return bdrv_make_zero(blk->root, flags); |
| } |
| |
| void blk_inc_in_flight(BlockBackend *blk) |
| { |
| atomic_inc(&blk->in_flight); |
| } |
| |
| void blk_dec_in_flight(BlockBackend *blk) |
| { |
| atomic_dec(&blk->in_flight); |
| aio_wait_kick(); |
| } |
| |
| static void error_callback_bh(void *opaque) |
| { |
| struct BlockBackendAIOCB *acb = opaque; |
| |
| blk_dec_in_flight(acb->blk); |
| acb->common.cb(acb->common.opaque, acb->ret); |
| qemu_aio_unref(acb); |
| } |
| |
| BlockAIOCB *blk_abort_aio_request(BlockBackend *blk, |
| BlockCompletionFunc *cb, |
| void *opaque, int ret) |
| { |
| struct BlockBackendAIOCB *acb; |
| |
| blk_inc_in_flight(blk); |
| acb = blk_aio_get(&block_backend_aiocb_info, blk, cb, opaque); |
| acb->blk = blk; |
| acb->ret = ret; |
| |
| aio_bh_schedule_oneshot(blk_get_aio_context(blk), error_callback_bh, acb); |
| return &acb->common; |
| } |
| |
| typedef struct BlkAioEmAIOCB { |
| BlockAIOCB common; |
| BlkRwCo rwco; |
| int bytes; |
| bool has_returned; |
| } BlkAioEmAIOCB; |
| |
| static const AIOCBInfo blk_aio_em_aiocb_info = { |
| .aiocb_size = sizeof(BlkAioEmAIOCB), |
| }; |
| |
| static void blk_aio_complete(BlkAioEmAIOCB *acb) |
| { |
| if (acb->has_returned) { |
| acb->common.cb(acb->common.opaque, acb->rwco.ret); |
| blk_dec_in_flight(acb->rwco.blk); |
| qemu_aio_unref(acb); |
| } |
| } |
| |
| static void blk_aio_complete_bh(void *opaque) |
| { |
| BlkAioEmAIOCB *acb = opaque; |
| assert(acb->has_returned); |
| blk_aio_complete(acb); |
| } |
| |
| static BlockAIOCB *blk_aio_prwv(BlockBackend *blk, int64_t offset, int bytes, |
| void *iobuf, CoroutineEntry co_entry, |
| BdrvRequestFlags flags, |
| BlockCompletionFunc *cb, void *opaque) |
| { |
| BlkAioEmAIOCB *acb; |
| Coroutine *co; |
| |
| blk_inc_in_flight(blk); |
| acb = blk_aio_get(&blk_aio_em_aiocb_info, blk, cb, opaque); |
| acb->rwco = (BlkRwCo) { |
| .blk = blk, |
| .offset = offset, |
| .iobuf = iobuf, |
| .flags = flags, |
| .ret = NOT_DONE, |
| }; |
| acb->bytes = bytes; |
| acb->has_returned = false; |
| |
| co = qemu_coroutine_create(co_entry, acb); |
| bdrv_coroutine_enter(blk_bs(blk), co); |
| |
| acb->has_returned = true; |
| if (acb->rwco.ret != NOT_DONE) { |
| aio_bh_schedule_oneshot(blk_get_aio_context(blk), |
| blk_aio_complete_bh, acb); |
| } |
| |
| return &acb->common; |
| } |
| |
| static void blk_aio_read_entry(void *opaque) |
| { |
| BlkAioEmAIOCB *acb = opaque; |
| BlkRwCo *rwco = &acb->rwco; |
| QEMUIOVector *qiov = rwco->iobuf; |
| |
| if (rwco->blk->quiesce_counter) { |
| blk_dec_in_flight(rwco->blk); |
| blk_wait_while_drained(rwco->blk); |
| blk_inc_in_flight(rwco->blk); |
| } |
| |
| assert(qiov->size == acb->bytes); |
| rwco->ret = blk_co_preadv(rwco->blk, rwco->offset, acb->bytes, |
| qiov, rwco->flags); |
| blk_aio_complete(acb); |
| } |
| |
| static void blk_aio_write_entry(void *opaque) |
| { |
| BlkAioEmAIOCB *acb = opaque; |
| BlkRwCo *rwco = &acb->rwco; |
| QEMUIOVector *qiov = rwco->iobuf; |
| |
| if (rwco->blk->quiesce_counter) { |
| blk_dec_in_flight(rwco->blk); |
| blk_wait_while_drained(rwco->blk); |
| blk_inc_in_flight(rwco->blk); |
| } |
| |
| assert(!qiov || qiov->size == acb->bytes); |
| rwco->ret = blk_co_pwritev(rwco->blk, rwco->offset, acb->bytes, |
| qiov, rwco->flags); |
| blk_aio_complete(acb); |
| } |
| |
| BlockAIOCB *blk_aio_pwrite_zeroes(BlockBackend *blk, int64_t offset, |
| int count, BdrvRequestFlags flags, |
| BlockCompletionFunc *cb, void *opaque) |
| { |
| return blk_aio_prwv(blk, offset, count, NULL, blk_aio_write_entry, |
| flags | BDRV_REQ_ZERO_WRITE, cb, opaque); |
| } |
| |
| int blk_pread(BlockBackend *blk, int64_t offset, void *buf, int count) |
| { |
| int ret = blk_prw(blk, offset, buf, count, blk_read_entry, 0); |
| if (ret < 0) { |
| return ret; |
| } |
| return count; |
| } |
| |
| int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int count, |
| BdrvRequestFlags flags) |
| { |
| int ret = blk_prw(blk, offset, (void *) buf, count, blk_write_entry, |
| flags); |
| if (ret < 0) { |
| return ret; |
| } |
| return count; |
| } |
| |
| int64_t blk_getlength(BlockBackend *blk) |
| { |
| if (!blk_is_available(blk)) { |
| return -ENOMEDIUM; |
| } |
| |
| return bdrv_getlength(blk_bs(blk)); |
| } |
| |
| void blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr) |
| { |
| if (!blk_bs(blk)) { |
| *nb_sectors_ptr = 0; |
| } else { |
| bdrv_get_geometry(blk_bs(blk), nb_sectors_ptr); |
| } |
| } |
| |
| int64_t blk_nb_sectors(BlockBackend *blk) |
| { |
| if (!blk_is_available(blk)) { |
| return -ENOMEDIUM; |
| } |
| |
| return bdrv_nb_sectors(blk_bs(blk)); |
| } |
| |
| BlockAIOCB *blk_aio_preadv(BlockBackend *blk, int64_t offset, |
| QEMUIOVector *qiov, BdrvRequestFlags flags, |
| BlockCompletionFunc *cb, void *opaque) |
| { |
| return blk_aio_prwv(blk, offset, qiov->size, qiov, |
| blk_aio_read_entry, flags, cb, opaque); |
| } |
| |
| BlockAIOCB *blk_aio_pwritev(BlockBackend *blk, int64_t offset, |
| QEMUIOVector *qiov, BdrvRequestFlags flags, |
| BlockCompletionFunc *cb, void *opaque) |
| { |
| return blk_aio_prwv(blk, offset, qiov->size, qiov, |
| blk_aio_write_entry, flags, cb, opaque); |
| } |
| |
| static void blk_aio_flush_entry(void *opaque) |
| { |
| BlkAioEmAIOCB *acb = opaque; |
| BlkRwCo *rwco = &acb->rwco; |
| |
| rwco->ret = blk_co_flush(rwco->blk); |
| blk_aio_complete(acb); |
| } |
| |
| BlockAIOCB *blk_aio_flush(BlockBackend *blk, |
| BlockCompletionFunc *cb, void *opaque) |
| { |
| return blk_aio_prwv(blk, 0, 0, NULL, blk_aio_flush_entry, 0, cb, opaque); |
| } |
| |
| static void blk_aio_pdiscard_entry(void *opaque) |
| { |
| BlkAioEmAIOCB *acb = opaque; |
| BlkRwCo *rwco = &acb->rwco; |
| |
| rwco->ret = blk_co_pdiscard(rwco->blk, rwco->offset, acb->bytes); |
| blk_aio_complete(acb); |
| } |
| |
| BlockAIOCB *blk_aio_pdiscard(BlockBackend *blk, |
| int64_t offset, int bytes, |
| BlockCompletionFunc *cb, void *opaque) |
| { |
| return blk_aio_prwv(blk, offset, bytes, NULL, blk_aio_pdiscard_entry, 0, |
| cb, opaque); |
| } |
| |
| void blk_aio_cancel(BlockAIOCB *acb) |
| { |
| bdrv_aio_cancel(acb); |
| } |
| |
| void blk_aio_cancel_async(BlockAIOCB *acb) |
| { |
| bdrv_aio_cancel_async(acb); |
| } |
| |
| int blk_co_ioctl(BlockBackend *blk, unsigned long int req, void *buf) |
| { |
| blk_wait_while_drained(blk); |
| |
| if (!blk_is_available(blk)) { |
| return -ENOMEDIUM; |
| } |
| |
| return bdrv_co_ioctl(blk_bs(blk), req, buf); |
| } |
| |
| static void blk_ioctl_entry(void *opaque) |
| { |
| BlkRwCo *rwco = opaque; |
| QEMUIOVector *qiov = rwco->iobuf; |
| |
| rwco->ret = blk_co_ioctl(rwco->blk, rwco->offset, |
| qiov->iov[0].iov_base); |
| aio_wait_kick(); |
| } |
| |
| int blk_ioctl(BlockBackend *blk, unsigned long int req, void *buf) |
| { |
| return blk_prw(blk, req, buf, 0, blk_ioctl_entry, 0); |
| } |
| |
| static void blk_aio_ioctl_entry(void *opaque) |
| { |
| BlkAioEmAIOCB *acb = opaque; |
| BlkRwCo *rwco = &acb->rwco; |
| |
| rwco->ret = blk_co_ioctl(rwco->blk, rwco->offset, rwco->iobuf); |
| |
| blk_aio_complete(acb); |
| } |
| |
| BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf, |
| BlockCompletionFunc *cb, void *opaque) |
| { |
| return blk_aio_prwv(blk, req, 0, buf, blk_aio_ioctl_entry, 0, cb, opaque); |
| } |
| |
| int blk_co_pdiscard(BlockBackend *blk, int64_t offset, int bytes) |
| { |
| int ret; |
| |
| blk_wait_while_drained(blk); |
| |
| ret = blk_check_byte_request(blk, offset, bytes); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| return bdrv_co_pdiscard(blk->root, offset, bytes); |
| } |
| |
| int blk_co_flush(BlockBackend *blk) |
| { |
| blk_wait_while_drained(blk); |
| |
| if (!blk_is_available(blk)) { |
| return -ENOMEDIUM; |
| } |
| |
| return bdrv_co_flush(blk_bs(blk)); |
| } |
| |
| static void blk_flush_entry(void *opaque) |
| { |
| BlkRwCo *rwco = opaque; |
| rwco->ret = blk_co_flush(rwco->blk); |
| aio_wait_kick(); |
| } |
| |
| int blk_flush(BlockBackend *blk) |
| { |
| return blk_prw(blk, 0, NULL, 0, blk_flush_entry, 0); |
| } |
| |
| void blk_drain(BlockBackend *blk) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (bs) { |
| bdrv_drained_begin(bs); |
| } |
| |
| /* We may have -ENOMEDIUM completions in flight */ |
| AIO_WAIT_WHILE(blk_get_aio_context(blk), |
| atomic_mb_read(&blk->in_flight) > 0); |
| |
| if (bs) { |
| bdrv_drained_end(bs); |
| } |
| } |
| |
| void blk_drain_all(void) |
| { |
| BlockBackend *blk = NULL; |
| |
| bdrv_drain_all_begin(); |
| |
| while ((blk = blk_all_next(blk)) != NULL) { |
| AioContext *ctx = blk_get_aio_context(blk); |
| |
| aio_context_acquire(ctx); |
| |
| /* We may have -ENOMEDIUM completions in flight */ |
| AIO_WAIT_WHILE(ctx, atomic_mb_read(&blk->in_flight) > 0); |
| |
| aio_context_release(ctx); |
| } |
| |
| bdrv_drain_all_end(); |
| } |
| |
| void blk_set_on_error(BlockBackend *blk, BlockdevOnError on_read_error, |
| BlockdevOnError on_write_error) |
| { |
| blk->on_read_error = on_read_error; |
| blk->on_write_error = on_write_error; |
| } |
| |
| BlockdevOnError blk_get_on_error(BlockBackend *blk, bool is_read) |
| { |
| return is_read ? blk->on_read_error : blk->on_write_error; |
| } |
| |
| BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read, |
| int error) |
| { |
| BlockdevOnError on_err = blk_get_on_error(blk, is_read); |
| |
| switch (on_err) { |
| case BLOCKDEV_ON_ERROR_ENOSPC: |
| return (error == ENOSPC) ? |
| BLOCK_ERROR_ACTION_STOP : BLOCK_ERROR_ACTION_REPORT; |
| case BLOCKDEV_ON_ERROR_STOP: |
| return BLOCK_ERROR_ACTION_STOP; |
| case BLOCKDEV_ON_ERROR_REPORT: |
| return BLOCK_ERROR_ACTION_REPORT; |
| case BLOCKDEV_ON_ERROR_IGNORE: |
| return BLOCK_ERROR_ACTION_IGNORE; |
| case BLOCKDEV_ON_ERROR_AUTO: |
| default: |
| abort(); |
| } |
| } |
| |
| static void send_qmp_error_event(BlockBackend *blk, |
| BlockErrorAction action, |
| bool is_read, int error) |
| { |
| IoOperationType optype; |
| BlockDriverState *bs = blk_bs(blk); |
| |
| optype = is_read ? IO_OPERATION_TYPE_READ : IO_OPERATION_TYPE_WRITE; |
| qapi_event_send_block_io_error(blk_name(blk), !!bs, |
| bs ? bdrv_get_node_name(bs) : NULL, optype, |
| action, blk_iostatus_is_enabled(blk), |
| error == ENOSPC, strerror(error)); |
| } |
| |
| /* This is done by device models because, while the block layer knows |
| * about the error, it does not know whether an operation comes from |
| * the device or the block layer (from a job, for example). |
| */ |
| void blk_error_action(BlockBackend *blk, BlockErrorAction action, |
| bool is_read, int error) |
| { |
| assert(error >= 0); |
| |
| if (action == BLOCK_ERROR_ACTION_STOP) { |
| /* First set the iostatus, so that "info block" returns an iostatus |
| * that matches the events raised so far (an additional error iostatus |
| * is fine, but not a lost one). |
| */ |
| blk_iostatus_set_err(blk, error); |
| |
| /* Then raise the request to stop the VM and the event. |
| * qemu_system_vmstop_request_prepare has two effects. First, |
| * it ensures that the STOP event always comes after the |
| * BLOCK_IO_ERROR event. Second, it ensures that even if management |
| * can observe the STOP event and do a "cont" before the STOP |
| * event is issued, the VM will not stop. In this case, vm_start() |
| * also ensures that the STOP/RESUME pair of events is emitted. |
| */ |
| qemu_system_vmstop_request_prepare(); |
| send_qmp_error_event(blk, action, is_read, error); |
| qemu_system_vmstop_request(RUN_STATE_IO_ERROR); |
| } else { |
| send_qmp_error_event(blk, action, is_read, error); |
| } |
| } |
| |
| bool blk_is_read_only(BlockBackend *blk) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (bs) { |
| return bdrv_is_read_only(bs); |
| } else { |
| return blk->root_state.read_only; |
| } |
| } |
| |
| bool blk_is_sg(BlockBackend *blk) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (!bs) { |
| return false; |
| } |
| |
| return bdrv_is_sg(bs); |
| } |
| |
| bool blk_enable_write_cache(BlockBackend *blk) |
| { |
| return blk->enable_write_cache; |
| } |
| |
| void blk_set_enable_write_cache(BlockBackend *blk, bool wce) |
| { |
| blk->enable_write_cache = wce; |
| } |
| |
| void blk_invalidate_cache(BlockBackend *blk, Error **errp) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (!bs) { |
| error_setg(errp, "Device '%s' has no medium", blk->name); |
| return; |
| } |
| |
| bdrv_invalidate_cache(bs, errp); |
| } |
| |
| bool blk_is_inserted(BlockBackend *blk) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| return bs && bdrv_is_inserted(bs); |
| } |
| |
| bool blk_is_available(BlockBackend *blk) |
| { |
| return blk_is_inserted(blk) && !blk_dev_is_tray_open(blk); |
| } |
| |
| void blk_lock_medium(BlockBackend *blk, bool locked) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (bs) { |
| bdrv_lock_medium(bs, locked); |
| } |
| } |
| |
| void blk_eject(BlockBackend *blk, bool eject_flag) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| char *id; |
| |
| if (bs) { |
| bdrv_eject(bs, eject_flag); |
| } |
| |
| /* Whether or not we ejected on the backend, |
| * the frontend experienced a tray event. */ |
| id = blk_get_attached_dev_id(blk); |
| qapi_event_send_device_tray_moved(blk_name(blk), id, |
| eject_flag); |
| g_free(id); |
| } |
| |
| int blk_get_flags(BlockBackend *blk) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (bs) { |
| return bdrv_get_flags(bs); |
| } else { |
| return blk->root_state.open_flags; |
| } |
| } |
| |
| /* Returns the minimum request alignment, in bytes; guaranteed nonzero */ |
| uint32_t blk_get_request_alignment(BlockBackend *blk) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| return bs ? bs->bl.request_alignment : BDRV_SECTOR_SIZE; |
| } |
| |
| /* Returns the maximum transfer length, in bytes; guaranteed nonzero */ |
| uint32_t blk_get_max_transfer(BlockBackend *blk) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| uint32_t max = 0; |
| |
| if (bs) { |
| max = bs->bl.max_transfer; |
| } |
| return MIN_NON_ZERO(max, INT_MAX); |
| } |
| |
| int blk_get_max_iov(BlockBackend *blk) |
| { |
| return blk->root->bs->bl.max_iov; |
| } |
| |
| void blk_set_guest_block_size(BlockBackend *blk, int align) |
| { |
| blk->guest_block_size = align; |
| } |
| |
| void *blk_try_blockalign(BlockBackend *blk, size_t size) |
| { |
| return qemu_try_blockalign(blk ? blk_bs(blk) : NULL, size); |
| } |
| |
| void *blk_blockalign(BlockBackend *blk, size_t size) |
| { |
| return qemu_blockalign(blk ? blk_bs(blk) : NULL, size); |
| } |
| |
| bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (!bs) { |
| return false; |
| } |
| |
| return bdrv_op_is_blocked(bs, op, errp); |
| } |
| |
| void blk_op_unblock(BlockBackend *blk, BlockOpType op, Error *reason) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (bs) { |
| bdrv_op_unblock(bs, op, reason); |
| } |
| } |
| |
| void blk_op_block_all(BlockBackend *blk, Error *reason) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (bs) { |
| bdrv_op_block_all(bs, reason); |
| } |
| } |
| |
| void blk_op_unblock_all(BlockBackend *blk, Error *reason) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (bs) { |
| bdrv_op_unblock_all(bs, reason); |
| } |
| } |
| |
| AioContext *blk_get_aio_context(BlockBackend *blk) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (bs) { |
| AioContext *ctx = bdrv_get_aio_context(blk_bs(blk)); |
| assert(ctx == blk->ctx); |
| } |
| |
| return blk->ctx; |
| } |
| |
| static AioContext *blk_aiocb_get_aio_context(BlockAIOCB *acb) |
| { |
| BlockBackendAIOCB *blk_acb = DO_UPCAST(BlockBackendAIOCB, common, acb); |
| return blk_get_aio_context(blk_acb->blk); |
| } |
| |
| static int blk_do_set_aio_context(BlockBackend *blk, AioContext *new_context, |
| bool update_root_node, Error **errp) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| ThrottleGroupMember *tgm = &blk->public.throttle_group_member; |
| int ret; |
| |
| if (bs) { |
| if (update_root_node) { |
| ret = bdrv_child_try_set_aio_context(bs, new_context, blk->root, |
| errp); |
| if (ret < 0) { |
| return ret; |
| } |
| } |
| if (tgm->throttle_state) { |
| bdrv_drained_begin(bs); |
| throttle_group_detach_aio_context(tgm); |
| throttle_group_attach_aio_context(tgm, new_context); |
| bdrv_drained_end(bs); |
| } |
| } |
| |
| blk->ctx = new_context; |
| return 0; |
| } |
| |
| int blk_set_aio_context(BlockBackend *blk, AioContext *new_context, |
| Error **errp) |
| { |
| return blk_do_set_aio_context(blk, new_context, true, errp); |
| } |
| |
| static bool blk_root_can_set_aio_ctx(BdrvChild *child, AioContext *ctx, |
| GSList **ignore, Error **errp) |
| { |
| BlockBackend *blk = child->opaque; |
| |
| if (blk->allow_aio_context_change) { |
| return true; |
| } |
| |
| /* Only manually created BlockBackends that are not attached to anything |
| * can change their AioContext without updating their user. */ |
| if (!blk->name || blk->dev) { |
| /* TODO Add BB name/QOM path */ |
| error_setg(errp, "Cannot change iothread of active block backend"); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| static void blk_root_set_aio_ctx(BdrvChild *child, AioContext *ctx, |
| GSList **ignore) |
| { |
| BlockBackend *blk = child->opaque; |
| blk_do_set_aio_context(blk, ctx, false, &error_abort); |
| } |
| |
| void blk_add_aio_context_notifier(BlockBackend *blk, |
| void (*attached_aio_context)(AioContext *new_context, void *opaque), |
| void (*detach_aio_context)(void *opaque), void *opaque) |
| { |
| BlockBackendAioNotifier *notifier; |
| BlockDriverState *bs = blk_bs(blk); |
| |
| notifier = g_new(BlockBackendAioNotifier, 1); |
| notifier->attached_aio_context = attached_aio_context; |
| notifier->detach_aio_context = detach_aio_context; |
| notifier->opaque = opaque; |
| QLIST_INSERT_HEAD(&blk->aio_notifiers, notifier, list); |
| |
| if (bs) { |
| bdrv_add_aio_context_notifier(bs, attached_aio_context, |
| detach_aio_context, opaque); |
| } |
| } |
| |
| void blk_remove_aio_context_notifier(BlockBackend *blk, |
| void (*attached_aio_context)(AioContext *, |
| void *), |
| void (*detach_aio_context)(void *), |
| void *opaque) |
| { |
| BlockBackendAioNotifier *notifier; |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (bs) { |
| bdrv_remove_aio_context_notifier(bs, attached_aio_context, |
| detach_aio_context, opaque); |
| } |
| |
| QLIST_FOREACH(notifier, &blk->aio_notifiers, list) { |
| if (notifier->attached_aio_context == attached_aio_context && |
| notifier->detach_aio_context == detach_aio_context && |
| notifier->opaque == opaque) { |
| QLIST_REMOVE(notifier, list); |
| g_free(notifier); |
| return; |
| } |
| } |
| |
| abort(); |
| } |
| |
| void blk_add_remove_bs_notifier(BlockBackend *blk, Notifier *notify) |
| { |
| notifier_list_add(&blk->remove_bs_notifiers, notify); |
| } |
| |
| void blk_add_insert_bs_notifier(BlockBackend *blk, Notifier *notify) |
| { |
| notifier_list_add(&blk->insert_bs_notifiers, notify); |
| } |
| |
| void blk_io_plug(BlockBackend *blk) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (bs) { |
| bdrv_io_plug(bs); |
| } |
| } |
| |
| void blk_io_unplug(BlockBackend *blk) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| |
| if (bs) { |
| bdrv_io_unplug(bs); |
| } |
| } |
| |
| BlockAcctStats *blk_get_stats(BlockBackend *blk) |
| { |
| return &blk->stats; |
| } |
| |
| void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk, |
| BlockCompletionFunc *cb, void *opaque) |
| { |
| return qemu_aio_get(aiocb_info, blk_bs(blk), cb, opaque); |
| } |
| |
| int coroutine_fn blk_co_pwrite_zeroes(BlockBackend *blk, int64_t offset, |
| int bytes, BdrvRequestFlags flags) |
| { |
| return blk_co_pwritev(blk, offset, bytes, NULL, |
| flags | BDRV_REQ_ZERO_WRITE); |
| } |
| |
| int blk_pwrite_compressed(BlockBackend *blk, int64_t offset, const void *buf, |
| int count) |
| { |
| return blk_prw(blk, offset, (void *) buf, count, blk_write_entry, |
| BDRV_REQ_WRITE_COMPRESSED); |
| } |
| |
| int blk_truncate(BlockBackend *blk, int64_t offset, PreallocMode prealloc, |
| Error **errp) |
| { |
| if (!blk_is_available(blk)) { |
| error_setg(errp, "No medium inserted"); |
| return -ENOMEDIUM; |
| } |
| |
| return bdrv_truncate(blk->root, offset, prealloc, errp); |
| } |
| |
| static void blk_pdiscard_entry(void *opaque) |
| { |
| BlkRwCo *rwco = opaque; |
| QEMUIOVector *qiov = rwco->iobuf; |
| |
| rwco->ret = blk_co_pdiscard(rwco->blk, rwco->offset, qiov->size); |
| aio_wait_kick(); |
| } |
| |
| int blk_pdiscard(BlockBackend *blk, int64_t offset, int bytes) |
| { |
| return blk_prw(blk, offset, NULL, bytes, blk_pdiscard_entry, 0); |
| } |
| |
| int blk_save_vmstate(BlockBackend *blk, const uint8_t *buf, |
| int64_t pos, int size) |
| { |
| int ret; |
| |
| if (!blk_is_available(blk)) { |
| return -ENOMEDIUM; |
| } |
| |
| ret = bdrv_save_vmstate(blk_bs(blk), buf, pos, size); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| if (ret == size && !blk->enable_write_cache) { |
| ret = bdrv_flush(blk_bs(blk)); |
| } |
| |
| return ret < 0 ? ret : size; |
| } |
| |
| int blk_load_vmstate(BlockBackend *blk, uint8_t *buf, int64_t pos, int size) |
| { |
| if (!blk_is_available(blk)) { |
| return -ENOMEDIUM; |
| } |
| |
| return bdrv_load_vmstate(blk_bs(blk), buf, pos, size); |
| } |
| |
| int blk_probe_blocksizes(BlockBackend *blk, BlockSizes *bsz) |
| { |
| if (!blk_is_available(blk)) { |
| return -ENOMEDIUM; |
| } |
| |
| return bdrv_probe_blocksizes(blk_bs(blk), bsz); |
| } |
| |
| int blk_probe_geometry(BlockBackend *blk, HDGeometry *geo) |
| { |
| if (!blk_is_available(blk)) { |
| return -ENOMEDIUM; |
| } |
| |
| return bdrv_probe_geometry(blk_bs(blk), geo); |
| } |
| |
| /* |
| * Updates the BlockBackendRootState object with data from the currently |
| * attached BlockDriverState. |
| */ |
| void blk_update_root_state(BlockBackend *blk) |
| { |
| assert(blk->root); |
| |
| blk->root_state.open_flags = blk->root->bs->open_flags; |
| blk->root_state.read_only = blk->root->bs->read_only; |
| blk->root_state.detect_zeroes = blk->root->bs->detect_zeroes; |
| } |
| |
| /* |
| * Returns the detect-zeroes setting to be used for bdrv_open() of a |
| * BlockDriverState which is supposed to inherit the root state. |
| */ |
| bool blk_get_detect_zeroes_from_root_state(BlockBackend *blk) |
| { |
| return blk->root_state.detect_zeroes; |
| } |
| |
| /* |
| * Returns the flags to be used for bdrv_open() of a BlockDriverState which is |
| * supposed to inherit the root state. |
| */ |
| int blk_get_open_flags_from_root_state(BlockBackend *blk) |
| { |
| int bs_flags; |
| |
| bs_flags = blk->root_state.read_only ? 0 : BDRV_O_RDWR; |
| bs_flags |= blk->root_state.open_flags & ~BDRV_O_RDWR; |
| |
| return bs_flags; |
| } |
| |
| BlockBackendRootState *blk_get_root_state(BlockBackend *blk) |
| { |
| return &blk->root_state; |
| } |
| |
| int blk_commit_all(void) |
| { |
| BlockBackend *blk = NULL; |
| |
| while ((blk = blk_all_next(blk)) != NULL) { |
| AioContext *aio_context = blk_get_aio_context(blk); |
| |
| aio_context_acquire(aio_context); |
| if (blk_is_inserted(blk) && blk->root->bs->backing) { |
| int ret = bdrv_commit(blk->root->bs); |
| if (ret < 0) { |
| aio_context_release(aio_context); |
| return ret; |
| } |
| } |
| aio_context_release(aio_context); |
| } |
| return 0; |
| } |
| |
| |
| /* throttling disk I/O limits */ |
| void blk_set_io_limits(BlockBackend *blk, ThrottleConfig *cfg) |
| { |
| throttle_group_config(&blk->public.throttle_group_member, cfg); |
| } |
| |
| void blk_io_limits_disable(BlockBackend *blk) |
| { |
| BlockDriverState *bs = blk_bs(blk); |
| ThrottleGroupMember *tgm = &blk->public.throttle_group_member; |
| assert(tgm->throttle_state); |
| if (bs) { |
| bdrv_drained_begin(bs); |
| } |
| throttle_group_unregister_tgm(tgm); |
| if (bs) { |
| bdrv_drained_end(bs); |
| } |
| } |
| |
| /* should be called before blk_set_io_limits if a limit is set */ |
| void blk_io_limits_enable(BlockBackend *blk, const char *group) |
| { |
| assert(!blk->public.throttle_group_member.throttle_state); |
| throttle_group_register_tgm(&blk->public.throttle_group_member, |
| group, blk_get_aio_context(blk)); |
| } |
| |
| void blk_io_limits_update_group(BlockBackend *blk, const char *group) |
| { |
| /* this BB is not part of any group */ |
| if (!blk->public.throttle_group_member.throttle_state) { |
| return; |
| } |
| |
| /* this BB is a part of the same group than the one we want */ |
| if (!g_strcmp0(throttle_group_get_name(&blk->public.throttle_group_member), |
| group)) { |
| return; |
| } |
| |
| /* need to change the group this bs belong to */ |
| blk_io_limits_disable(blk); |
| blk_io_limits_enable(blk, group); |
| } |
| |
| static void blk_root_drained_begin(BdrvChild *child) |
| { |
| BlockBackend *blk = child->opaque; |
| |
| if (++blk->quiesce_counter == 1) { |
| if (blk->dev_ops && blk->dev_ops->drained_begin) { |
| blk->dev_ops->drained_begin(blk->dev_opaque); |
| } |
| } |
| |
| /* Note that blk->root may not be accessible here yet if we are just |
| * attaching to a BlockDriverState that is drained. Use child instead. */ |
| |
| if (atomic_fetch_inc(&blk->public.throttle_group_member.io_limits_disabled) == 0) { |
| throttle_group_restart_tgm(&blk->public.throttle_group_member); |
| } |
| } |
| |
| static bool blk_root_drained_poll(BdrvChild *child) |
| { |
| BlockBackend *blk = child->opaque; |
| assert(blk->quiesce_counter); |
| return !!blk->in_flight; |
| } |
| |
| static void blk_root_drained_end(BdrvChild *child, int *drained_end_counter) |
| { |
| BlockBackend *blk = child->opaque; |
| assert(blk->quiesce_counter); |
| |
| assert(blk->public.throttle_group_member.io_limits_disabled); |
| atomic_dec(&blk->public.throttle_group_member.io_limits_disabled); |
| |
| if (--blk->quiesce_counter == 0) { |
| if (blk->dev_ops && blk->dev_ops->drained_end) { |
| blk->dev_ops->drained_end(blk->dev_opaque); |
| } |
| while (qemu_co_enter_next(&blk->queued_requests, NULL)) { |
| /* Resume all queued requests */ |
| } |
| } |
| } |
| |
| void blk_register_buf(BlockBackend *blk, void *host, size_t size) |
| { |
| bdrv_register_buf(blk_bs(blk), host, size); |
| } |
| |
| void blk_unregister_buf(BlockBackend *blk, void *host) |
| { |
| bdrv_unregister_buf(blk_bs(blk), host); |
| } |
| |
| int coroutine_fn blk_co_copy_range(BlockBackend *blk_in, int64_t off_in, |
| BlockBackend *blk_out, int64_t off_out, |
| int bytes, BdrvRequestFlags read_flags, |
| BdrvRequestFlags write_flags) |
| { |
| int r; |
| r = blk_check_byte_request(blk_in, off_in, bytes); |
| if (r) { |
| return r; |
| } |
| r = blk_check_byte_request(blk_out, off_out, bytes); |
| if (r) { |
| return r; |
| } |
| return bdrv_co_copy_range(blk_in->root, off_in, |
| blk_out->root, off_out, |
| bytes, read_flags, write_flags); |
| } |
| |
| const BdrvChild *blk_root(BlockBackend *blk) |
| { |
| return blk->root; |
| } |