mii/qemu
1
0
Fork 0
mirror of https://github.com/mii443/qemu.git synced 2025-09-02 07:09:47 +00:00
Code Issues Packages Projects Releases Wiki Activity

block: Mark bdrv_replace_node() GRAPH_WRLOCK

Browse Source 
Instead of taking the writer lock internally, require callers to already
hold it when calling bdrv_replace_node(). Its callers may already want
to hold the graph lock and so wouldn't be able to call functions that
take it internally.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231027155333.420094-17-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf
2023-10-27 17:53:25 +02:00
parent 5c0ef4954f
commit ccd6a37947
7 changed files with 64 additions and 35 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
block/commit.c
View File

@ -68,6 +68,7 @@ static void commit_abort(Job *job)
{
CommitBlockJob *s = container_of(job, CommitBlockJob, common.job);
BlockDriverState *top_bs = blk_bs(s->top);
BlockDriverState *commit_top_backing_bs;
if (s->chain_frozen) {
bdrv_graph_rdlock_main_loop();
@ -94,8 +95,12 @@ static void commit_abort(Job *job)
* XXX Can (or should) we somehow keep 'consistent read' blocked even
* after the failed/cancelled commit job is gone? If we already wrote
* something to base, the intermediate images aren't valid any more. */
bdrv_replace_node(s->commit_top_bs, s->commit_top_bs->backing->bs,
&error_abort);
commit_top_backing_bs = s->commit_top_bs->backing->bs;
bdrv_drained_begin(commit_top_backing_bs);
bdrv_graph_wrlock(commit_top_backing_bs);
bdrv_replace_node(s->commit_top_bs, commit_top_backing_bs, &error_abort);
bdrv_graph_wrunlock();
bdrv_drained_end(commit_top_backing_bs);
bdrv_unref(s->commit_top_bs);
bdrv_unref(top_bs);
@ -425,7 +430,11 @@ fail:
/* commit_top_bs has to be replaced after deleting the block job,
* otherwise this would fail because of lack of permissions. */
if (commit_top_bs) {
bdrv_drained_begin(top);
bdrv_graph_wrlock(top);
bdrv_replace_node(commit_top_bs, top, &error_abort);
bdrv_graph_wrunlock();
bdrv_drained_end(top);
}
}