Bitmap lock/unlock were added to bdrv_enable_dirty_bitmap in
8b1402ce, but some places were not updated correspondingly, which
leads to trying to take this lock twice, which is dead-lock. Fix this.

Actually, iotest 199 (about dirty bitmap postcopy migration) is broken
now, and this fixes it.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20180625165745.25259-3-vsementsov@virtuozzo.com
Signed-off-by: NJohn Snow <jsnow@redhat.com>

dirty_bitmap_load_header return code is obtained but not handled. Fix
this.

Bug was introduced in b35ebdf0
"migration: add postcopy migration of dirty bitmaps" with the whole
function.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20180530112424.204835-1-vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>

When pulling in headers that are in the same directory as the C file (as
opposed to one in include/), we should use its relative path, without a
directory.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NJuan Quintela <quintela@redhat.com>

Release buf on error path too.

Bug was introduced in b35ebdf0 "migration: add postcopy
migration of dirty bitmaps" with the whole function.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20180427142002.21930-3-vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
CC: qemu-stable@nongnu.org
Signed-off-by: NEric Blake <eblake@redhat.com>

Postcopy migration of dirty bitmaps. Only named dirty bitmaps are migrated.

If destination qemu is already containing a dirty bitmap with the same name
as a migrated bitmap (for the same node), then, if their granularities are
the same the migration will be done, otherwise the error will be generated.

If destination qemu doesn't contain such bitmap it will be created.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 20180313180320.339796-12-vsementsov@virtuozzo.com
[Changed '+' to '*' as per list discussion. --js]
Signed-off-by: NJohn Snow <jsnow@redhat.com>