diff options
| author | Kevin Wolf <kwolf@redhat.com> | 2023-10-27 17:53:32 +0200 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2023-11-08 17:56:18 +0100 |
| commit | a4b740db5ee3db0d5b76a6ea9895875763453187 (patch) | |
| tree | 096757e6b1a3828e67daa3264a7d73e51e5c432c /block/qcow.c | |
| parent | 65ff757df04a541ae6a34c51267e54244627efef (diff) | |
block: Take graph lock for most of .bdrv_open
Most implementations of .bdrv_open first open their file child (which is
an operation that internally takes the write lock and therefore we
shouldn't hold the graph lock while calling it), and afterwards many
operations that require holding the graph lock, e.g. for accessing
bs->file.
This changes block drivers that follow this pattern to take the graph
lock after opening the child node.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20231027155333.420094-24-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'block/qcow.c')
| -rw-r--r-- | block/qcow.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/block/qcow.c b/block/qcow.c index 1e2835f1f4..c6d0e15f1e 100644 --- a/block/qcow.c +++ b/block/qcow.c @@ -124,9 +124,11 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, ret = bdrv_open_file_child(NULL, options, "file", bs, errp); if (ret < 0) { - goto fail; + goto fail_unlocked; } + bdrv_graph_rdlock_main_loop(); + ret = bdrv_pread(bs->file, 0, sizeof(header), &header, 0); if (ret < 0) { goto fail; @@ -301,11 +303,9 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, } /* Disable migration when qcow images are used */ - bdrv_graph_rdlock_main_loop(); error_setg(&s->migration_blocker, "The qcow format used by node '%s' " "does not support live migration", bdrv_get_device_or_node_name(bs)); - bdrv_graph_rdunlock_main_loop(); ret = migrate_add_blocker_normal(&s->migration_blocker, errp); if (ret < 0) { @@ -315,9 +315,12 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, qobject_unref(encryptopts); qapi_free_QCryptoBlockOpenOptions(crypto_opts); qemu_co_mutex_init(&s->lock); + bdrv_graph_rdunlock_main_loop(); return 0; - fail: +fail: + bdrv_graph_rdunlock_main_loop(); +fail_unlocked: g_free(s->l1_table); qemu_vfree(s->l2_cache); g_free(s->cluster_cache); |