Finally, copy-before-write gets own .bdrv_open and .bdrv_close handlers, block_init() call and becomes available through bdrv_open().
To achieve this: - cbw_init gets unused flags argument and becomes cbw_open - block_copy_state_free() call moved to new cbw_close() - in bdrv_cbw_append: - options are completed with driver and node-name, and we can simply use bdrv_insert_node() to do both open and drained replacing - in bdrv_cbw_drop: - cbw_close() is now responsible for freeing s->bcs, so don't do it here Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> Reviewed-by: Max Reitz <mre...@redhat.com> --- block/copy-before-write.c | 60 ++++++++++++++++++--------------------- 1 file changed, 28 insertions(+), 32 deletions(-) diff --git a/block/copy-before-write.c b/block/copy-before-write.c index ba2466a328..6ed5bce1f1 100644 --- a/block/copy-before-write.c +++ b/block/copy-before-write.c @@ -144,7 +144,8 @@ static void cbw_child_perm(BlockDriverState *bs, BdrvChild *c, } } -static int cbw_init(BlockDriverState *bs, QDict *options, Error **errp) +static int cbw_open(BlockDriverState *bs, QDict *options, int flags, + Error **errp) { BDRVCopyBeforeWriteState *s = bs->opaque; BdrvDirtyBitmap *copy_bitmap; @@ -191,10 +192,21 @@ static int cbw_init(BlockDriverState *bs, QDict *options, Error **errp) return 0; } +static void cbw_close(BlockDriverState *bs) +{ + BDRVCopyBeforeWriteState *s = bs->opaque; + + block_copy_state_free(s->bcs); + s->bcs = NULL; +} + BlockDriver bdrv_cbw_filter = { .format_name = "copy-before-write", .instance_size = sizeof(BDRVCopyBeforeWriteState), + .bdrv_open = cbw_open, + .bdrv_close = cbw_close, + .bdrv_co_preadv = cbw_co_preadv, .bdrv_co_pwritev = cbw_co_pwritev, .bdrv_co_pwrite_zeroes = cbw_co_pwrite_zeroes, @@ -216,57 +228,41 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source, Error **errp) { ERRP_GUARD(); - int ret; BDRVCopyBeforeWriteState *state; BlockDriverState *top; QDict *opts; assert(source->total_sectors == target->total_sectors); - top = bdrv_new_open_driver(&bdrv_cbw_filter, filter_node_name, - BDRV_O_RDWR, errp); - if (!top) { - error_prepend(errp, "Cannot open driver: "); - return NULL; - } - state = top->opaque; - opts = qdict_new(); + qdict_put_str(opts, "driver", "copy-before-write"); + if (filter_node_name) { + qdict_put_str(opts, "node-name", filter_node_name); + } qdict_put_str(opts, "file", bdrv_get_node_name(source)); qdict_put_str(opts, "target", bdrv_get_node_name(target)); qdict_put_bool(opts, "x-deprecated-compress", compress); - ret = cbw_init(top, opts, errp); - qobject_unref(opts); - if (ret < 0) { - goto fail; - } - - bdrv_drained_begin(source); - ret = bdrv_replace_node(source, top, errp); - bdrv_drained_end(source); - if (ret < 0) { - error_prepend(errp, "Cannot append copy-before-write filter: "); - goto fail; + top = bdrv_insert_node(source, opts, BDRV_O_RDWR, errp); + if (!top) { + return NULL; } + state = top->opaque; *bcs = state->bcs; return top; - -fail: - block_copy_state_free(state->bcs); - bdrv_unref(top); - return NULL; } void bdrv_cbw_drop(BlockDriverState *bs) { - BDRVCopyBeforeWriteState *s = bs->opaque; - bdrv_drop_filter(bs, &error_abort); - - block_copy_state_free(s->bcs); - bdrv_unref(bs); } + +static void cbw_init(void) +{ + bdrv_register(&bdrv_cbw_filter); +} + +block_init(cbw_init); -- 2.29.2