diff options
Diffstat (limited to 'qemu/block/block-backend.c')
| -rw-r--r-- | qemu/block/block-backend.c | 1089 |
1 files changed, 902 insertions, 187 deletions
diff --git a/qemu/block/block-backend.c b/qemu/block/block-backend.c index aee8a1202..16c9d5e0f 100644 --- a/qemu/block/block-backend.c +++ b/qemu/block/block-backend.c @@ -10,74 +10,105 @@ * 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 "sysemu/blockdev.h" +#include "sysemu/sysemu.h" #include "qapi-event.h" +#include "qemu/id.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); + struct BlockBackend { char *name; int refcnt; - BlockDriverState *bs; + BdrvChild *root; DriveInfo *legacy_dinfo; /* null unless created by drive_new() */ - QTAILQ_ENTRY(BlockBackend) link; /* for blk_backends */ + QTAILQ_ENTRY(BlockBackend) link; /* for block_backends */ + QTAILQ_ENTRY(BlockBackend) monitor_link; /* for monitor_block_backends */ void *dev; /* attached device model, if any */ /* TODO change to DeviceState when all users are qdevified */ 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; + + bool allow_write_beyond_eof; + + NotifierList remove_bs_notifiers, insert_bs_notifiers; }; typedef struct BlockBackendAIOCB { BlockAIOCB common; QEMUBH *bh; + 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); -/* All the BlockBackends (except for hidden ones) */ -static QTAILQ_HEAD(, BlockBackend) blk_backends = - QTAILQ_HEAD_INITIALIZER(blk_backends); +/* 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 const BdrvChildRole child_root = { + .inherit_options = blk_root_inherit_options, +}; /* - * Create a new BlockBackend with @name, with a reference count of one. - * @name must not be null or empty. - * Fail if a BlockBackend with this name already exists. + * Create a new BlockBackend with a reference count of one. * Store an error through @errp on failure, unless it's null. * Return the new BlockBackend on success, null on failure. */ -BlockBackend *blk_new(const char *name, Error **errp) +BlockBackend *blk_new(Error **errp) { BlockBackend *blk; - assert(name && name[0]); - if (!id_wellformed(name)) { - error_setg(errp, "Invalid device name"); - return NULL; - } - if (blk_by_name(name)) { - error_setg(errp, "Device with id '%s' already exists", name); - return NULL; - } - if (bdrv_find_node(name)) { - error_setg(errp, - "Device name '%s' conflicts with an existing node name", - name); - return NULL; - } - blk = g_new0(BlockBackend, 1); - blk->name = g_strdup(name); blk->refcnt = 1; - QTAILQ_INSERT_TAIL(&blk_backends, blk, link); + notifier_list_init(&blk->remove_bs_notifiers); + notifier_list_init(&blk->insert_bs_notifiers); + QTAILQ_INSERT_TAIL(&block_backends, blk, link); return blk; } @@ -85,18 +116,18 @@ BlockBackend *blk_new(const char *name, Error **errp) * Create a new BlockBackend with a new BlockDriverState attached. * Otherwise just like blk_new(), which see. */ -BlockBackend *blk_new_with_bs(const char *name, Error **errp) +BlockBackend *blk_new_with_bs(Error **errp) { BlockBackend *blk; BlockDriverState *bs; - blk = blk_new(name, errp); + blk = blk_new(errp); if (!blk) { return NULL; } bs = bdrv_new_root(); - blk->bs = bs; + blk->root = bdrv_root_attach_child(bs, "root", &child_root); bs->blk = blk; return blk; } @@ -113,44 +144,46 @@ BlockBackend *blk_new_with_bs(const char *name, Error **errp) * though, so callers of this function have to be able to specify @filename and * @flags. */ -BlockBackend *blk_new_open(const char *name, const char *filename, - const char *reference, QDict *options, int flags, - Error **errp) +BlockBackend *blk_new_open(const char *filename, const char *reference, + QDict *options, int flags, Error **errp) { BlockBackend *blk; int ret; - blk = blk_new_with_bs(name, errp); + blk = blk_new_with_bs(errp); if (!blk) { QDECREF(options); return NULL; } - ret = bdrv_open(&blk->bs, filename, reference, options, flags, NULL, errp); + ret = bdrv_open(&blk->root->bs, filename, reference, options, flags, errp); if (ret < 0) { blk_unref(blk); return NULL; } + blk_set_enable_write_cache(blk, true); + return blk; } static void blk_delete(BlockBackend *blk) { assert(!blk->refcnt); + assert(!blk->name); assert(!blk->dev); - if (blk->bs) { - assert(blk->bs->blk == blk); - blk->bs->blk = NULL; - bdrv_unref(blk->bs); - blk->bs = NULL; + if (blk->root) { + blk_remove_bs(blk); } - /* Avoid double-remove after blk_hide_on_behalf_of_hmp_drive_del() */ - if (blk->name[0]) { - QTAILQ_REMOVE(&blk_backends, blk, link); + assert(QLIST_EMPTY(&blk->remove_bs_notifiers.notifiers)); + assert(QLIST_EMPTY(&blk->insert_bs_notifiers.notifiers)); + if (blk->root_state.throttle_state) { + g_free(blk->root_state.throttle_group); + throttle_group_unref(blk->root_state.throttle_state); } - g_free(blk->name); + QTAILQ_REMOVE(&block_backends, blk, link); drive_info_del(blk->legacy_dinfo); + block_acct_cleanup(&blk->stats); g_free(blk); } @@ -164,6 +197,11 @@ static void drive_info_del(DriveInfo *dinfo) g_free(dinfo); } +int blk_get_refcnt(BlockBackend *blk) +{ + return blk ? blk->refcnt : 0; +} + /* * Increment @blk's reference count. * @blk must not be null. @@ -189,7 +227,32 @@ void blk_unref(BlockBackend *blk) } /* - * Return the BlockBackend after @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). + */ +static 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. * @@ -200,17 +263,91 @@ void blk_unref(BlockBackend *blk) */ BlockBackend *blk_next(BlockBackend *blk) { - return blk ? QTAILQ_NEXT(blk, link) : QTAILQ_FIRST(&blk_backends); + return blk ? QTAILQ_NEXT(blk, monitor_link) + : QTAILQ_FIRST(&monitor_block_backends); +} + +/* + * Iterates over all BlockDriverStates which are attached to a BlockBackend. + * This function is for use by bdrv_next(). + * + * @bs must be NULL or a BDS that is attached to a BB. + */ +BlockDriverState *blk_next_root_bs(BlockDriverState *bs) +{ + BlockBackend *blk; + + if (bs) { + assert(bs->blk); + blk = bs->blk; + } else { + blk = NULL; + } + + do { + blk = blk_all_next(blk); + } while (blk && !blk->root); + + return blk ? blk->root->bs : NULL; +} + +/* + * 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. - * Wart: the name is empty iff @blk has been hidden with - * blk_hide_on_behalf_of_hmp_drive_del(). + * Returns an empty string iff @blk is not referenced by the monitor. */ const char *blk_name(BlockBackend *blk) { - return blk->name; + return blk->name ?: ""; } /* @@ -219,10 +356,10 @@ const char *blk_name(BlockBackend *blk) */ BlockBackend *blk_by_name(const char *name) { - BlockBackend *blk; + BlockBackend *blk = NULL; assert(name); - QTAILQ_FOREACH(blk, &blk_backends, link) { + while ((blk = blk_next(blk)) != NULL) { if (!strcmp(name, blk->name)) { return blk; } @@ -235,7 +372,7 @@ BlockBackend *blk_by_name(const char *name) */ BlockDriverState *blk_bs(BlockBackend *blk) { - return blk->bs; + return blk->root ? blk->root->bs : NULL; } /* @@ -263,9 +400,9 @@ DriveInfo *blk_set_legacy_dinfo(BlockBackend *blk, DriveInfo *dinfo) */ BlockBackend *blk_by_legacy_dinfo(DriveInfo *dinfo) { - BlockBackend *blk; + BlockBackend *blk = NULL; - QTAILQ_FOREACH(blk, &blk_backends, link) { + while ((blk = blk_next(blk)) != NULL) { if (blk->legacy_dinfo == dinfo) { return blk; } @@ -274,21 +411,32 @@ BlockBackend *blk_by_legacy_dinfo(DriveInfo *dinfo) } /* - * Hide @blk. - * @blk must not have been hidden already. - * Make attached BlockDriverState, if any, anonymous. - * Once hidden, @blk is invisible to all functions that don't receive - * it as argument. For example, blk_by_name() won't return it. - * Strictly for use by do_drive_del(). - * TODO get rid of it! + * Disassociates the currently associated BlockDriverState from @blk. */ -void blk_hide_on_behalf_of_hmp_drive_del(BlockBackend *blk) +void blk_remove_bs(BlockBackend *blk) { - QTAILQ_REMOVE(&blk_backends, blk, link); - blk->name[0] = 0; - if (blk->bs) { - bdrv_make_anon(blk->bs); - } + assert(blk->root->bs->blk == blk); + + notifier_list_notify(&blk->remove_bs_notifiers, blk); + + blk_update_root_state(blk); + + blk->root->bs->blk = NULL; + bdrv_root_unref_child(blk->root); + blk->root = NULL; +} + +/* + * Associates a new BlockDriverState with @blk. + */ +void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs) +{ + assert(!blk->root && !bs->blk); + bdrv_ref(bs); + blk->root = bdrv_root_attach_child(bs, "root", &child_root); + bs->blk = blk; + + notifier_list_notify(&blk->insert_bs_notifiers, blk); } /* @@ -303,7 +451,7 @@ int blk_attach_dev(BlockBackend *blk, void *dev) } blk_ref(blk); blk->dev = dev; - bdrv_iostatus_reset(blk->bs); + blk_iostatus_reset(blk); return 0; } @@ -330,7 +478,7 @@ void blk_detach_dev(BlockBackend *blk, void *dev) blk->dev = NULL; blk->dev_ops = NULL; blk->dev_opaque = NULL; - bdrv_set_guest_block_size(blk->bs, 512); + blk->guest_block_size = 512; blk_unref(blk); } @@ -364,18 +512,15 @@ void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops, void blk_dev_change_media_cb(BlockBackend *blk, bool load) { if (blk->dev_ops && blk->dev_ops->change_media_cb) { - bool tray_was_closed = !blk_dev_is_tray_open(blk); + bool tray_was_open, tray_is_open; + tray_was_open = blk_dev_is_tray_open(blk); blk->dev_ops->change_media_cb(blk->dev_opaque, load); - if (tray_was_closed) { - /* tray open */ - qapi_event_send_device_tray_moved(blk_name(blk), - true, &error_abort); - } - if (load) { - /* tray close */ - qapi_event_send_device_tray_moved(blk_name(blk), - false, &error_abort); + tray_is_open = blk_dev_is_tray_open(blk); + + if (tray_was_open != tray_is_open) { + qapi_event_send_device_tray_moved(blk_name(blk), tray_is_open, + &error_abort); } } } @@ -390,6 +535,14 @@ bool blk_dev_has_removable_media(BlockBackend *blk) } /* + * 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. */ @@ -405,7 +558,7 @@ void blk_dev_eject_request(BlockBackend *blk, bool force) */ bool blk_dev_is_tray_open(BlockBackend *blk) { - if (blk->dev_ops && blk->dev_ops->is_tray_open) { + if (blk_dev_has_tray(blk)) { return blk->dev_ops->is_tray_open(blk->dev_opaque); } return false; @@ -435,7 +588,53 @@ void blk_dev_resize_cb(BlockBackend *blk) void blk_iostatus_enable(BlockBackend *blk) { - bdrv_iostatus_enable(blk->bs); + 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)) { + BlockDriverState *bs = blk_bs(blk); + blk->iostatus = BLOCK_DEVICE_IO_STATUS_OK; + if (bs && bs->job) { + block_job_iostatus_reset(bs->job); + } + } +} + +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; } static int blk_check_byte_request(BlockBackend *blk, int64_t offset, @@ -447,21 +646,23 @@ static int blk_check_byte_request(BlockBackend *blk, int64_t offset, return -EIO; } - if (!blk_is_inserted(blk)) { + if (!blk_is_available(blk)) { return -ENOMEDIUM; } - len = blk_getlength(blk); - if (len < 0) { - return len; - } - if (offset < 0) { return -EIO; } - if (offset > len || len - offset < size) { - 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; @@ -482,48 +683,144 @@ static int blk_check_request(BlockBackend *blk, int64_t sector_num, nb_sectors * BDRV_SECTOR_SIZE); } -int blk_read(BlockBackend *blk, int64_t sector_num, uint8_t *buf, - int nb_sectors) +static int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset, + unsigned int bytes, QEMUIOVector *qiov, + BdrvRequestFlags flags) { - int ret = blk_check_request(blk, sector_num, nb_sectors); + int ret = blk_check_byte_request(blk, offset, bytes); if (ret < 0) { return ret; } - return bdrv_read(blk->bs, sector_num, buf, nb_sectors); + return bdrv_co_do_preadv(blk_bs(blk), offset, bytes, qiov, flags); } -int blk_read_unthrottled(BlockBackend *blk, int64_t sector_num, uint8_t *buf, - int nb_sectors) +static int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset, + unsigned int bytes, QEMUIOVector *qiov, + BdrvRequestFlags flags) { - int ret = blk_check_request(blk, sector_num, nb_sectors); + int ret; + + ret = blk_check_byte_request(blk, offset, bytes); if (ret < 0) { return ret; } - return bdrv_read_unthrottled(blk->bs, sector_num, buf, nb_sectors); + if (!blk->enable_write_cache) { + flags |= BDRV_REQ_FUA; + } + + return bdrv_co_do_pwritev(blk_bs(blk), offset, bytes, qiov, flags); } -int blk_write(BlockBackend *blk, int64_t sector_num, const uint8_t *buf, - int nb_sectors) +typedef struct BlkRwCo { + BlockBackend *blk; + int64_t offset; + QEMUIOVector *qiov; + int ret; + BdrvRequestFlags flags; +} BlkRwCo; + +static void blk_read_entry(void *opaque) { - int ret = blk_check_request(blk, sector_num, nb_sectors); - if (ret < 0) { - return ret; + BlkRwCo *rwco = opaque; + + rwco->ret = blk_co_preadv(rwco->blk, rwco->offset, rwco->qiov->size, + rwco->qiov, rwco->flags); +} + +static void blk_write_entry(void *opaque) +{ + BlkRwCo *rwco = opaque; + + rwco->ret = blk_co_pwritev(rwco->blk, rwco->offset, rwco->qiov->size, + rwco->qiov, rwco->flags); +} + +static int blk_prw(BlockBackend *blk, int64_t offset, uint8_t *buf, + int64_t bytes, CoroutineEntry co_entry, + BdrvRequestFlags flags) +{ + AioContext *aio_context; + QEMUIOVector qiov; + struct iovec iov; + Coroutine *co; + BlkRwCo rwco; + + iov = (struct iovec) { + .iov_base = buf, + .iov_len = bytes, + }; + qemu_iovec_init_external(&qiov, &iov, 1); + + rwco = (BlkRwCo) { + .blk = blk, + .offset = offset, + .qiov = &qiov, + .flags = flags, + .ret = NOT_DONE, + }; + + co = qemu_coroutine_create(co_entry); + qemu_coroutine_enter(co, &rwco); + + aio_context = blk_get_aio_context(blk); + while (rwco.ret == NOT_DONE) { + aio_poll(aio_context, true); } - return bdrv_write(blk->bs, sector_num, buf, nb_sectors); + return rwco.ret; } -int blk_write_zeroes(BlockBackend *blk, int64_t sector_num, - int nb_sectors, BdrvRequestFlags flags) +static int blk_rw(BlockBackend *blk, int64_t sector_num, uint8_t *buf, + int nb_sectors, CoroutineEntry co_entry, + BdrvRequestFlags flags) { - int ret = blk_check_request(blk, sector_num, nb_sectors); + if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { + return -EINVAL; + } + + return blk_prw(blk, sector_num << BDRV_SECTOR_BITS, buf, + nb_sectors << BDRV_SECTOR_BITS, co_entry, flags); +} + +int blk_read(BlockBackend *blk, int64_t sector_num, uint8_t *buf, + int nb_sectors) +{ + return blk_rw(blk, sector_num, buf, nb_sectors, blk_read_entry, 0); +} + +int blk_read_unthrottled(BlockBackend *blk, int64_t sector_num, uint8_t *buf, + int nb_sectors) +{ + BlockDriverState *bs = blk_bs(blk); + bool enabled; + int ret; + + ret = blk_check_request(blk, sector_num, nb_sectors); if (ret < 0) { return ret; } - return bdrv_write_zeroes(blk->bs, sector_num, nb_sectors, flags); + enabled = bs->io_limits_enabled; + bs->io_limits_enabled = false; + ret = blk_read(blk, sector_num, buf, nb_sectors); + bs->io_limits_enabled = enabled; + return ret; +} + +int blk_write(BlockBackend *blk, int64_t sector_num, const uint8_t *buf, + int nb_sectors) +{ + return blk_rw(blk, sector_num, (uint8_t*) buf, nb_sectors, + blk_write_entry, 0); +} + +int blk_write_zeroes(BlockBackend *blk, int64_t sector_num, + int nb_sectors, BdrvRequestFlags flags) +{ + return blk_rw(blk, sector_num, NULL, nb_sectors, blk_write_entry, + flags | BDRV_REQ_ZERO_WRITE); } static void error_callback_bh(void *opaque) @@ -534,13 +831,15 @@ static void error_callback_bh(void *opaque) qemu_aio_unref(acb); } -static BlockAIOCB *abort_aio_request(BlockBackend *blk, BlockCompletionFunc *cb, - void *opaque, int ret) +BlockAIOCB *blk_abort_aio_request(BlockBackend *blk, + BlockCompletionFunc *cb, + void *opaque, int ret) { struct BlockBackendAIOCB *acb; QEMUBH *bh; acb = blk_aio_get(&block_backend_aiocb_info, blk, cb, opaque); + acb->blk = blk; acb->ret = ret; bh = aio_bh_new(blk_get_aio_context(blk), error_callback_bh, acb); @@ -550,82 +849,182 @@ static BlockAIOCB *abort_aio_request(BlockBackend *blk, BlockCompletionFunc *cb, return &acb->common; } +typedef struct BlkAioEmAIOCB { + BlockAIOCB common; + BlkRwCo rwco; + int bytes; + bool has_returned; + QEMUBH* bh; +} BlkAioEmAIOCB; + +static const AIOCBInfo blk_aio_em_aiocb_info = { + .aiocb_size = sizeof(BlkAioEmAIOCB), +}; + +static void blk_aio_complete(BlkAioEmAIOCB *acb) +{ + if (acb->bh) { + assert(acb->has_returned); + qemu_bh_delete(acb->bh); + } + if (acb->has_returned) { + acb->common.cb(acb->common.opaque, acb->rwco.ret); + qemu_aio_unref(acb); + } +} + +static void blk_aio_complete_bh(void *opaque) +{ + blk_aio_complete(opaque); +} + +static BlockAIOCB *blk_aio_prwv(BlockBackend *blk, int64_t offset, int bytes, + QEMUIOVector *qiov, CoroutineEntry co_entry, + BdrvRequestFlags flags, + BlockCompletionFunc *cb, void *opaque) +{ + BlkAioEmAIOCB *acb; + Coroutine *co; + + acb = blk_aio_get(&blk_aio_em_aiocb_info, blk, cb, opaque); + acb->rwco = (BlkRwCo) { + .blk = blk, + .offset = offset, + .qiov = qiov, + .flags = flags, + .ret = NOT_DONE, + }; + acb->bytes = bytes; + acb->bh = NULL; + acb->has_returned = false; + + co = qemu_coroutine_create(co_entry); + qemu_coroutine_enter(co, acb); + + acb->has_returned = true; + if (acb->rwco.ret != NOT_DONE) { + acb->bh = aio_bh_new(blk_get_aio_context(blk), blk_aio_complete_bh, acb); + qemu_bh_schedule(acb->bh); + } + + return &acb->common; +} + +static void blk_aio_read_entry(void *opaque) +{ + BlkAioEmAIOCB *acb = opaque; + BlkRwCo *rwco = &acb->rwco; + + assert(rwco->qiov->size == acb->bytes); + rwco->ret = blk_co_preadv(rwco->blk, rwco->offset, acb->bytes, + rwco->qiov, rwco->flags); + blk_aio_complete(acb); +} + +static void blk_aio_write_entry(void *opaque) +{ + BlkAioEmAIOCB *acb = opaque; + BlkRwCo *rwco = &acb->rwco; + + assert(!rwco->qiov || rwco->qiov->size == acb->bytes); + rwco->ret = blk_co_pwritev(rwco->blk, rwco->offset, acb->bytes, + rwco->qiov, rwco->flags); + blk_aio_complete(acb); +} + BlockAIOCB *blk_aio_write_zeroes(BlockBackend *blk, int64_t sector_num, int nb_sectors, BdrvRequestFlags flags, BlockCompletionFunc *cb, void *opaque) { - int ret = blk_check_request(blk, sector_num, nb_sectors); - if (ret < 0) { - return abort_aio_request(blk, cb, opaque, ret); + if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { + return blk_abort_aio_request(blk, cb, opaque, -EINVAL); } - return bdrv_aio_write_zeroes(blk->bs, sector_num, nb_sectors, flags, - cb, opaque); + return blk_aio_prwv(blk, sector_num << BDRV_SECTOR_BITS, + nb_sectors << BDRV_SECTOR_BITS, 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_check_byte_request(blk, offset, count); + int ret = blk_prw(blk, offset, buf, count, blk_read_entry, 0); if (ret < 0) { return ret; } - - return bdrv_pread(blk->bs, offset, buf, count); + return count; } int blk_pwrite(BlockBackend *blk, int64_t offset, const void *buf, int count) { - int ret = blk_check_byte_request(blk, offset, count); + int ret = blk_prw(blk, offset, (void*) buf, count, blk_write_entry, 0); if (ret < 0) { return ret; } - - return bdrv_pwrite(blk->bs, offset, buf, count); + return count; } int64_t blk_getlength(BlockBackend *blk) { - return bdrv_getlength(blk->bs); + if (!blk_is_available(blk)) { + return -ENOMEDIUM; + } + + return bdrv_getlength(blk_bs(blk)); } void blk_get_geometry(BlockBackend *blk, uint64_t *nb_sectors_ptr) { - bdrv_get_geometry(blk->bs, 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) { - return bdrv_nb_sectors(blk->bs); + if (!blk_is_available(blk)) { + return -ENOMEDIUM; + } + + return bdrv_nb_sectors(blk_bs(blk)); } BlockAIOCB *blk_aio_readv(BlockBackend *blk, int64_t sector_num, QEMUIOVector *iov, int nb_sectors, BlockCompletionFunc *cb, void *opaque) { - int ret = blk_check_request(blk, sector_num, nb_sectors); - if (ret < 0) { - return abort_aio_request(blk, cb, opaque, ret); + if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { + return blk_abort_aio_request(blk, cb, opaque, -EINVAL); } - return bdrv_aio_readv(blk->bs, sector_num, iov, nb_sectors, cb, opaque); + assert(nb_sectors << BDRV_SECTOR_BITS == iov->size); + return blk_aio_prwv(blk, sector_num << BDRV_SECTOR_BITS, iov->size, iov, + blk_aio_read_entry, 0, cb, opaque); } BlockAIOCB *blk_aio_writev(BlockBackend *blk, int64_t sector_num, QEMUIOVector *iov, int nb_sectors, BlockCompletionFunc *cb, void *opaque) { - int ret = blk_check_request(blk, sector_num, nb_sectors); - if (ret < 0) { - return abort_aio_request(blk, cb, opaque, ret); + if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { + return blk_abort_aio_request(blk, cb, opaque, -EINVAL); } - return bdrv_aio_writev(blk->bs, sector_num, iov, nb_sectors, cb, opaque); + assert(nb_sectors << BDRV_SECTOR_BITS == iov->size); + return blk_aio_prwv(blk, sector_num << BDRV_SECTOR_BITS, iov->size, iov, + blk_aio_write_entry, 0, cb, opaque); } BlockAIOCB *blk_aio_flush(BlockBackend *blk, BlockCompletionFunc *cb, void *opaque) { - return bdrv_aio_flush(blk->bs, cb, opaque); + if (!blk_is_available(blk)) { + return blk_abort_aio_request(blk, cb, opaque, -ENOMEDIUM); + } + + return bdrv_aio_flush(blk_bs(blk), cb, opaque); } BlockAIOCB *blk_aio_discard(BlockBackend *blk, @@ -634,10 +1033,10 @@ BlockAIOCB *blk_aio_discard(BlockBackend *blk, { int ret = blk_check_request(blk, sector_num, nb_sectors); if (ret < 0) { - return abort_aio_request(blk, cb, opaque, ret); + return blk_abort_aio_request(blk, cb, opaque, ret); } - return bdrv_aio_discard(blk->bs, sector_num, nb_sectors, cb, opaque); + return bdrv_aio_discard(blk_bs(blk), sector_num, nb_sectors, cb, opaque); } void blk_aio_cancel(BlockAIOCB *acb) @@ -661,18 +1060,26 @@ int blk_aio_multiwrite(BlockBackend *blk, BlockRequest *reqs, int num_reqs) } } - return bdrv_aio_multiwrite(blk->bs, reqs, num_reqs); + return bdrv_aio_multiwrite(blk_bs(blk), reqs, num_reqs); } int blk_ioctl(BlockBackend *blk, unsigned long int req, void *buf) { - return bdrv_ioctl(blk->bs, req, buf); + if (!blk_is_available(blk)) { + return -ENOMEDIUM; + } + + return bdrv_ioctl(blk_bs(blk), req, buf); } BlockAIOCB *blk_aio_ioctl(BlockBackend *blk, unsigned long int req, void *buf, BlockCompletionFunc *cb, void *opaque) { - return bdrv_aio_ioctl(blk->bs, req, buf, cb, opaque); + if (!blk_is_available(blk)) { + return blk_abort_aio_request(blk, cb, opaque, -ENOMEDIUM); + } + + return bdrv_aio_ioctl(blk_bs(blk), req, buf, cb, opaque); } int blk_co_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors) @@ -682,27 +1089,32 @@ int blk_co_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors) return ret; } - return bdrv_co_discard(blk->bs, sector_num, nb_sectors); + return bdrv_co_discard(blk_bs(blk), sector_num, nb_sectors); } int blk_co_flush(BlockBackend *blk) { - return bdrv_co_flush(blk->bs); + if (!blk_is_available(blk)) { + return -ENOMEDIUM; + } + + return bdrv_co_flush(blk_bs(blk)); } int blk_flush(BlockBackend *blk) { - return bdrv_flush(blk->bs); -} + if (!blk_is_available(blk)) { + return -ENOMEDIUM; + } -int blk_flush_all(void) -{ - return bdrv_flush_all(); + return bdrv_flush(blk_bs(blk)); } void blk_drain(BlockBackend *blk) { - bdrv_drain(blk->bs); + if (blk_bs(blk)) { + bdrv_drain(blk_bs(blk)); + } } void blk_drain_all(void) @@ -710,119 +1122,273 @@ void blk_drain_all(void) bdrv_drain_all(); } +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 bdrv_get_on_error(blk->bs, 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) { - return bdrv_get_error_action(blk->bs, is_read, 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; + default: + abort(); + } +} + +static void send_qmp_error_event(BlockBackend *blk, + BlockErrorAction action, + bool is_read, int error) +{ + IoOperationType optype; + + optype = is_read ? IO_OPERATION_TYPE_READ : IO_OPERATION_TYPE_WRITE; + qapi_event_send_block_io_error(blk_name(blk), optype, action, + blk_iostatus_is_enabled(blk), + error == ENOSPC, strerror(error), + &error_abort); } +/* 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) { - bdrv_error_action(blk->bs, action, is_read, 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); + } } int blk_is_read_only(BlockBackend *blk) { - return bdrv_is_read_only(blk->bs); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + return bdrv_is_read_only(bs); + } else { + return blk->root_state.read_only; + } } int blk_is_sg(BlockBackend *blk) { - return bdrv_is_sg(blk->bs); + BlockDriverState *bs = blk_bs(blk); + + if (!bs) { + return 0; + } + + return bdrv_is_sg(bs); } int blk_enable_write_cache(BlockBackend *blk) { - return bdrv_enable_write_cache(blk->bs); + return blk->enable_write_cache; } void blk_set_enable_write_cache(BlockBackend *blk, bool wce) { - bdrv_set_enable_write_cache(blk->bs, wce); + blk->enable_write_cache = wce; } void blk_invalidate_cache(BlockBackend *blk, Error **errp) { - bdrv_invalidate_cache(blk->bs, 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); } -int blk_is_inserted(BlockBackend *blk) +bool blk_is_available(BlockBackend *blk) { - return bdrv_is_inserted(blk->bs); + return blk_is_inserted(blk) && !blk_dev_is_tray_open(blk); } void blk_lock_medium(BlockBackend *blk, bool locked) { - bdrv_lock_medium(blk->bs, locked); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + bdrv_lock_medium(bs, locked); + } } void blk_eject(BlockBackend *blk, bool eject_flag) { - bdrv_eject(blk->bs, eject_flag); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + bdrv_eject(bs, eject_flag); + } } int blk_get_flags(BlockBackend *blk) { - return bdrv_get_flags(blk->bs); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + return bdrv_get_flags(bs); + } else { + return blk->root_state.open_flags; + } } int blk_get_max_transfer_length(BlockBackend *blk) { - return blk->bs->bl.max_transfer_length; + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + return bs->bl.max_transfer_length; + } else { + return 0; + } +} + +int blk_get_max_iov(BlockBackend *blk) +{ + return blk->root->bs->bl.max_iov; } void blk_set_guest_block_size(BlockBackend *blk, int align) { - bdrv_set_guest_block_size(blk->bs, 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 : NULL, size); + return qemu_blockalign(blk ? blk_bs(blk) : NULL, size); } bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp) { - return bdrv_op_is_blocked(blk->bs, op, 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) { - bdrv_op_unblock(blk->bs, op, reason); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + bdrv_op_unblock(bs, op, reason); + } } void blk_op_block_all(BlockBackend *blk, Error *reason) { - bdrv_op_block_all(blk->bs, reason); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + bdrv_op_block_all(bs, reason); + } } void blk_op_unblock_all(BlockBackend *blk, Error *reason) { - bdrv_op_unblock_all(blk->bs, reason); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + bdrv_op_unblock_all(bs, reason); + } } AioContext *blk_get_aio_context(BlockBackend *blk) { - return bdrv_get_aio_context(blk->bs); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + return bdrv_get_aio_context(bs); + } else { + return qemu_get_aio_context(); + } +} + +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); } void blk_set_aio_context(BlockBackend *blk, AioContext *new_context) { - bdrv_set_aio_context(blk->bs, new_context); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + bdrv_set_aio_context(bs, new_context); + } } 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) { - bdrv_add_aio_context_notifier(blk->bs, attached_aio_context, - detach_aio_context, opaque); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + bdrv_add_aio_context_notifier(bs, attached_aio_context, + detach_aio_context, opaque); + } } void blk_remove_aio_context_notifier(BlockBackend *blk, @@ -831,28 +1397,45 @@ void blk_remove_aio_context_notifier(BlockBackend *blk, void (*detach_aio_context)(void *), void *opaque) { - bdrv_remove_aio_context_notifier(blk->bs, attached_aio_context, - detach_aio_context, opaque); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + bdrv_remove_aio_context_notifier(bs, attached_aio_context, + detach_aio_context, opaque); + } } -void blk_add_close_notifier(BlockBackend *blk, Notifier *notify) +void blk_add_remove_bs_notifier(BlockBackend *blk, Notifier *notify) { - bdrv_add_close_notifier(blk->bs, 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) { - bdrv_io_plug(blk->bs); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + bdrv_io_plug(bs); + } } void blk_io_unplug(BlockBackend *blk) { - bdrv_io_unplug(blk->bs); + BlockDriverState *bs = blk_bs(blk); + + if (bs) { + bdrv_io_unplug(bs); + } } BlockAcctStats *blk_get_stats(BlockBackend *blk) { - return bdrv_get_stats(blk->bs); + return &blk->stats; } void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk, @@ -864,12 +1447,13 @@ void *blk_aio_get(const AIOCBInfo *aiocb_info, BlockBackend *blk, int coroutine_fn blk_co_write_zeroes(BlockBackend *blk, int64_t sector_num, int nb_sectors, BdrvRequestFlags flags) { - int ret = blk_check_request(blk, sector_num, nb_sectors); - if (ret < 0) { - return ret; + if (nb_sectors < 0 || nb_sectors > BDRV_REQUEST_MAX_SECTORS) { + return -EINVAL; } - return bdrv_co_write_zeroes(blk->bs, sector_num, nb_sectors, flags); + return blk_co_pwritev(blk, sector_num << BDRV_SECTOR_BITS, + nb_sectors << BDRV_SECTOR_BITS, NULL, + flags | BDRV_REQ_ZERO_WRITE); } int blk_write_compressed(BlockBackend *blk, int64_t sector_num, @@ -880,12 +1464,16 @@ int blk_write_compressed(BlockBackend *blk, int64_t sector_num, return ret; } - return bdrv_write_compressed(blk->bs, sector_num, buf, nb_sectors); + return bdrv_write_compressed(blk_bs(blk), sector_num, buf, nb_sectors); } int blk_truncate(BlockBackend *blk, int64_t offset) { - return bdrv_truncate(blk->bs, offset); + if (!blk_is_available(blk)) { + return -ENOMEDIUM; + } + + return bdrv_truncate(blk_bs(blk), offset); } int blk_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors) @@ -895,26 +1483,153 @@ int blk_discard(BlockBackend *blk, int64_t sector_num, int nb_sectors) return ret; } - return bdrv_discard(blk->bs, sector_num, nb_sectors); + return bdrv_discard(blk_bs(blk), sector_num, nb_sectors); } int blk_save_vmstate(BlockBackend *blk, const uint8_t *buf, int64_t pos, int size) { - return bdrv_save_vmstate(blk->bs, buf, pos, 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) { - return bdrv_load_vmstate(blk->bs, buf, pos, 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) { - return bdrv_probe_blocksizes(blk->bs, bsz); + if (!blk_is_available(blk)) { + return -ENOMEDIUM; + } + + return bdrv_probe_blocksizes(blk_bs(blk), bsz); } int blk_probe_geometry(BlockBackend *blk, HDGeometry *geo) { - return bdrv_probe_geometry(blk->bs, 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; + + if (blk->root_state.throttle_group) { + g_free(blk->root_state.throttle_group); + throttle_group_unref(blk->root_state.throttle_state); + } + if (blk->root->bs->throttle_state) { + const char *name = throttle_group_get_name(blk->root->bs); + blk->root_state.throttle_group = g_strdup(name); + blk->root_state.throttle_state = throttle_group_incref(name); + } else { + blk->root_state.throttle_group = NULL; + blk->root_state.throttle_state = NULL; + } +} + +/* + * Applies the information in the root state to the given BlockDriverState. This + * does not include the flags which have to be specified for bdrv_open(), use + * blk_get_open_flags_from_root_state() to inquire them. + */ +void blk_apply_root_state(BlockBackend *blk, BlockDriverState *bs) +{ + bs->detect_zeroes = blk->root_state.detect_zeroes; + if (blk->root_state.throttle_group) { + bdrv_io_limits_enable(bs, blk->root_state.throttle_group); + } +} + +/* + * 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; +} + +int blk_flush_all(void) +{ + BlockBackend *blk = NULL; + int result = 0; + + while ((blk = blk_all_next(blk)) != NULL) { + AioContext *aio_context = blk_get_aio_context(blk); + int ret; + + aio_context_acquire(aio_context); + if (blk_is_inserted(blk)) { + ret = blk_flush(blk); + if (ret < 0 && !result) { + result = ret; + } + } + aio_context_release(aio_context); + } + + return result; } |