Commit 741cc431 authored by Max Reitz's avatar Max Reitz
Browse files

nbd: Switch from close to eject notifier 



The NBD code uses the BDS close notifier to determine when a medium is
ejected. However, now it should use the BB's BDS removal notifier for
that instead of the BDS's close notifier.

Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
Reviewed-by: default avatarFam Zheng <famz@redhat.com>
Reviewed-by: default avatarKevin Wolf <kwolf@redhat.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent 5b9e0e46

blockdev-nbd.c

+5 −35
Original line number Diff line number Diff line
@@ -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);

nbd/server.c

+13 −0
Original line number Diff line number Diff line
@@ -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);