From a990a42b39338ffd12fb9640d792276313f75ed5 Mon Sep 17 00:00:00 2001 From: Lukas Straub Date: Sun, 18 Jul 2021 16:48:29 +0200 Subject: [PATCH] replication: Reduce usage of s->hidden_disk and s->secondary_disk In preparation for the next patch, initialize s->hidden_disk and s->secondary_disk later and replace access to them with local variables in the places where they aren't initialized yet. Signed-off-by: Lukas Straub Reviewed-by: Vladimir Sementsov-Ogievskiy Message-Id: <1eb9dc179267207d9c7eccaeb30761758e32e9ab.1626619393.git.lukasstraub2@web.de> Signed-off-by: Kevin Wolf --- block/replication.c | 45 ++++++++++++++++++++++++++++----------------- 1 file changed, 28 insertions(+), 17 deletions(-) diff --git a/block/replication.c b/block/replication.c index 9ad2dfdc69..25bbdf5d4b 100644 --- a/block/replication.c +++ b/block/replication.c @@ -366,27 +366,35 @@ static void reopen_backing_file(BlockDriverState *bs, bool writable, Error **errp) { BDRVReplicationState *s = bs->opaque; + BdrvChild *hidden_disk, *secondary_disk; BlockReopenQueue *reopen_queue = NULL; + /* + * s->hidden_disk and s->secondary_disk may not be set yet, as they will + * only be set after the children are writable. + */ + hidden_disk = bs->file->bs->backing; + secondary_disk = hidden_disk->bs->backing; + if (writable) { - s->orig_hidden_read_only = bdrv_is_read_only(s->hidden_disk->bs); - s->orig_secondary_read_only = bdrv_is_read_only(s->secondary_disk->bs); + s->orig_hidden_read_only = bdrv_is_read_only(hidden_disk->bs); + s->orig_secondary_read_only = bdrv_is_read_only(secondary_disk->bs); } - bdrv_subtree_drained_begin(s->hidden_disk->bs); - bdrv_subtree_drained_begin(s->secondary_disk->bs); + bdrv_subtree_drained_begin(hidden_disk->bs); + bdrv_subtree_drained_begin(secondary_disk->bs); if (s->orig_hidden_read_only) { QDict *opts = qdict_new(); qdict_put_bool(opts, BDRV_OPT_READ_ONLY, !writable); - reopen_queue = bdrv_reopen_queue(reopen_queue, s->hidden_disk->bs, + reopen_queue = bdrv_reopen_queue(reopen_queue, hidden_disk->bs, opts, true); } if (s->orig_secondary_read_only) { QDict *opts = qdict_new(); qdict_put_bool(opts, BDRV_OPT_READ_ONLY, !writable); - reopen_queue = bdrv_reopen_queue(reopen_queue, s->secondary_disk->bs, + reopen_queue = bdrv_reopen_queue(reopen_queue, secondary_disk->bs, opts, true); } @@ -401,8 +409,8 @@ static void reopen_backing_file(BlockDriverState *bs, bool writable, } } - bdrv_subtree_drained_end(s->hidden_disk->bs); - bdrv_subtree_drained_end(s->secondary_disk->bs); + bdrv_subtree_drained_end(hidden_disk->bs); + bdrv_subtree_drained_end(secondary_disk->bs); } static void backup_job_cleanup(BlockDriverState *bs) @@ -459,7 +467,7 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, BlockDriverState *bs = rs->opaque; BDRVReplicationState *s; BlockDriverState *top_bs; - BdrvChild *active_disk; + BdrvChild *active_disk, *hidden_disk, *secondary_disk; int64_t active_length, hidden_length, disk_length; AioContext *aio_context; Error *local_err = NULL; @@ -504,15 +512,15 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, return; } - s->hidden_disk = active_disk->bs->backing; - if (!s->hidden_disk->bs || !s->hidden_disk->bs->backing) { + hidden_disk = active_disk->bs->backing; + if (!hidden_disk->bs || !hidden_disk->bs->backing) { error_setg(errp, "Hidden disk doesn't have backing file"); aio_context_release(aio_context); return; } - s->secondary_disk = s->hidden_disk->bs->backing; - if (!s->secondary_disk->bs || !bdrv_has_blk(s->secondary_disk->bs)) { + secondary_disk = hidden_disk->bs->backing; + if (!secondary_disk->bs || !bdrv_has_blk(secondary_disk->bs)) { error_setg(errp, "The secondary disk doesn't have block backend"); aio_context_release(aio_context); return; @@ -520,8 +528,8 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, /* verify the length */ active_length = bdrv_getlength(active_disk->bs); - hidden_length = bdrv_getlength(s->hidden_disk->bs); - disk_length = bdrv_getlength(s->secondary_disk->bs); + hidden_length = bdrv_getlength(hidden_disk->bs); + disk_length = bdrv_getlength(secondary_disk->bs); if (active_length < 0 || hidden_length < 0 || disk_length < 0 || active_length != hidden_length || hidden_length != disk_length) { error_setg(errp, "Active disk, hidden disk, secondary disk's length" @@ -531,10 +539,10 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, } /* Must be true, or the bdrv_getlength() calls would have failed */ - assert(active_disk->bs->drv && s->hidden_disk->bs->drv); + assert(active_disk->bs->drv && hidden_disk->bs->drv); if (!active_disk->bs->drv->bdrv_make_empty || - !s->hidden_disk->bs->drv->bdrv_make_empty) { + !hidden_disk->bs->drv->bdrv_make_empty) { error_setg(errp, "Active disk or hidden disk doesn't support make_empty"); aio_context_release(aio_context); @@ -549,6 +557,9 @@ static void replication_start(ReplicationState *rs, ReplicationMode mode, return; } + s->hidden_disk = hidden_disk; + s->secondary_disk = secondary_disk; + /* start backup job now */ error_setg(&s->blocker, "Block device is in use by internal backup job");