mirror: Use real permissions in mirror/active commit block job

The mirror block job is mainly used for two different scenarios:
Mirroring to an otherwise unused, independent target node, or for active
commit where the target node is part of the backing chain of the source.

Similarly to the commit block job patch, we need to insert a new filter
node to keep the permissions correct during active commit.

Note that one change this implies is that job->blk points to
mirror_top_bs as its root now, and mirror_top_bs (rather than the actual
source node) contains the bs->job pointer. This requires qemu-img commit
to get the job by name now rather than just taking bs->job.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Fam Zheng <famz@redhat.com>
Acked-by: Max Reitz <mreitz@redhat.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/qemu-img.c b/qemu-img.c
index a48a471042..0c76d4caa7 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -814,6 +814,8 @@ static void run_block_job(BlockJob *job, Error **errp)
 {
     AioContext *aio_context = blk_get_aio_context(job->blk);
 
+    /* FIXME In error cases, the job simply goes away and we access a dangling
+     * pointer below. */
     aio_context_acquire(aio_context);
     do {
         aio_poll(aio_context, true);
@@ -835,6 +837,7 @@ static int img_commit(int argc, char **argv)
     const char *filename, *fmt, *cache, *base;
     BlockBackend *blk;
     BlockDriverState *bs, *base_bs;
+    BlockJob *job;
     bool progress = false, quiet = false, drop = false;
     bool writethrough;
     Error *local_err = NULL;
@@ -970,7 +973,8 @@ static int img_commit(int argc, char **argv)
         bdrv_ref(bs);
     }
 
-    run_block_job(bs->job, &local_err);
+    job = block_job_get("commit");
+    run_block_job(job, &local_err);
     if (local_err) {
         goto unref_backing;
     }