diff --git a/blockdev-nbd.c b/blockdev-nbd.c index 4a758ac314..9d6a21c33d 100644 --- a/blockdev-nbd.c +++ b/blockdev-nbd.c @@ -45,37 +45,11 @@ void qmp_nbd_server_start(SocketAddress *addr, Error **errp) } } -/* - * Hook into the BlockBackend notifiers to close the export when the - * backend is closed. - */ -typedef struct NBDCloseNotifier { - Notifier n; - NBDExport *exp; - QTAILQ_ENTRY(NBDCloseNotifier) next; -} NBDCloseNotifier; - -static QTAILQ_HEAD(, NBDCloseNotifier) close_notifiers = - QTAILQ_HEAD_INITIALIZER(close_notifiers); - -static void nbd_close_notifier(Notifier *n, void *data) -{ - NBDCloseNotifier *cn = DO_UPCAST(NBDCloseNotifier, n, n); - - notifier_remove(&cn->n); - QTAILQ_REMOVE(&close_notifiers, cn, next); - - nbd_export_close(cn->exp); - nbd_export_put(cn->exp); - g_free(cn); -} - void qmp_nbd_server_add(const char *device, bool has_writable, bool writable, Error **errp) { BlockBackend *blk; NBDExport *exp; - NBDCloseNotifier *n; if (server_fd == -1) { error_setg(errp, "NBD server not running"); @@ -113,19 +87,15 @@ void qmp_nbd_server_add(const char *device, bool has_writable, bool writable, nbd_export_set_name(exp, device); - n = g_new0(NBDCloseNotifier, 1); - n->n.notify = nbd_close_notifier; - n->exp = exp; - blk_add_close_notifier(blk, &n->n); - QTAILQ_INSERT_TAIL(&close_notifiers, n, next); + /* The list of named exports has a strong reference to this export now and + * our only way of accessing it is through nbd_export_find(), so we can drop + * the strong reference that is @exp. */ + nbd_export_put(exp); } void qmp_nbd_server_stop(Error **errp) { - while (!QTAILQ_EMPTY(&close_notifiers)) { - NBDCloseNotifier *cn = QTAILQ_FIRST(&close_notifiers); - nbd_close_notifier(&cn->n, nbd_export_get_blockdev(cn->exp)); - } + nbd_export_close_all(); if (server_fd != -1) { qemu_set_fd_handler(server_fd, NULL, NULL, NULL); diff --git a/nbd/server.c b/nbd/server.c index 7fa7f53768..1ec79cf411 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -64,6 +64,8 @@ struct NBDExport { QTAILQ_ENTRY(NBDExport) next; AioContext *ctx; + + Notifier eject_notifier; }; static QTAILQ_HEAD(, NBDExport) exports = QTAILQ_HEAD_INITIALIZER(exports); @@ -644,6 +646,12 @@ static void blk_aio_detach(void *opaque) exp->ctx = NULL; } +static void nbd_eject_notifier(Notifier *n, void *data) +{ + NBDExport *exp = container_of(n, NBDExport, eject_notifier); + nbd_export_close(exp); +} + NBDExport *nbd_export_new(BlockBackend *blk, off_t dev_offset, off_t size, uint32_t nbdflags, void (*close)(NBDExport *), Error **errp) @@ -666,6 +674,10 @@ NBDExport *nbd_export_new(BlockBackend *blk, off_t dev_offset, off_t size, exp->ctx = blk_get_aio_context(blk); blk_ref(blk); blk_add_aio_context_notifier(blk, blk_aio_attached, blk_aio_detach, exp); + + exp->eject_notifier.notify = nbd_eject_notifier; + blk_add_remove_bs_notifier(blk, &exp->eject_notifier); + /* * NBD exports are used for non-shared storage migration. Make sure * that BDRV_O_INACTIVE is cleared and the image is ready for write @@ -747,6 +759,7 @@ void nbd_export_put(NBDExport *exp) } if (exp->blk) { + notifier_remove(&exp->eject_notifier); blk_remove_aio_context_notifier(exp->blk, blk_aio_attached, blk_aio_detach, exp); blk_unref(exp->blk);