From 1f0cacb967bffc0d1284a2a5c6025b09f9a0f091 Mon Sep 17 00:00:00 2001 From: Vladimir Sementsov-Ogievskiy Date: Tue, 24 Aug 2021 11:38:36 +0300 Subject: [PATCH] block/copy-before-write: introduce cbw_init() Move part of bdrv_cbw_append() to new function cbw_open(). It's an intermediate step for adding normal .bdrv_open() handler to the filter. With this commit no logic is changed, but we have a function which will be turned into .bdrv_open() handler in future commit. Signed-off-by: Vladimir Sementsov-Ogievskiy Reviewed-by: Max Reitz Message-Id: <20210824083856.17408-15-vsementsov@virtuozzo.com> Signed-off-by: Hanna Reitz --- block/copy-before-write.c | 69 +++++++++++++++++++++++---------------- 1 file changed, 41 insertions(+), 28 deletions(-) diff --git a/block/copy-before-write.c b/block/copy-before-write.c index adbbc64aa9..a4fee645fd 100644 --- a/block/copy-before-write.c +++ b/block/copy-before-write.c @@ -144,6 +144,45 @@ static void cbw_child_perm(BlockDriverState *bs, BdrvChild *c, } } +static int cbw_init(BlockDriverState *top, BlockDriverState *source, + BlockDriverState *target, bool compress, Error **errp) +{ + BDRVCopyBeforeWriteState *state = top->opaque; + + top->total_sectors = source->total_sectors; + top->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED | + (BDRV_REQ_FUA & source->supported_write_flags); + top->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED | + ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) & + source->supported_zero_flags); + + bdrv_ref(target); + state->target = bdrv_attach_child(top, target, "target", &child_of_bds, + BDRV_CHILD_DATA, errp); + if (!state->target) { + error_prepend(errp, "Cannot attach target child: "); + return -EINVAL; + } + + bdrv_ref(source); + top->file = bdrv_attach_child(top, source, "file", &child_of_bds, + BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, + errp); + if (!top->file) { + error_prepend(errp, "Cannot attach file child: "); + return -EINVAL; + } + + state->bcs = block_copy_state_new(top->file, state->target, false, compress, + errp); + if (!state->bcs) { + error_prepend(errp, "Cannot create block-copy-state: "); + return -EINVAL; + } + + return 0; +} + BlockDriver bdrv_cbw_filter = { .format_name = "copy-before-write", .instance_size = sizeof(BDRVCopyBeforeWriteState), @@ -181,36 +220,10 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source, error_prepend(errp, "Cannot open driver: "); return NULL; } - state = top->opaque; - top->total_sectors = source->total_sectors; - top->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED | - (BDRV_REQ_FUA & source->supported_write_flags); - top->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED | - ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) & - source->supported_zero_flags); - bdrv_ref(target); - state->target = bdrv_attach_child(top, target, "target", &child_of_bds, - BDRV_CHILD_DATA, errp); - if (!state->target) { - error_prepend(errp, "Cannot attach target child: "); - goto fail; - } - - bdrv_ref(source); - top->file = bdrv_attach_child(top, source, "file", &child_of_bds, - BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, - errp); - if (!top->file) { - error_prepend(errp, "Cannot attach file child: "); - goto fail; - } - - state->bcs = block_copy_state_new(top->file, state->target, false, compress, - errp); - if (!state->bcs) { - error_prepend(errp, "Cannot create block-copy-state: "); + ret = cbw_init(top, source, target, compress, errp); + if (ret < 0) { goto fail; }