Merge remote-tracking branch 'remotes/jnsnow/tags/bitmaps-pull-request' into staging

Pull request

# gpg: Signature made Wed 20 Feb 2019 18:01:00 GMT
# gpg:                using RSA key F9B7ABDBBCACDF95BE76CBD07DEF8106AAFC390E
# gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>" [full]
# Primary key fingerprint: FAEB 9711 A12C F475 812F  18F2 88A9 064D 1835 61EB
#      Subkey fingerprint: F9B7 ABDB BCAC DF95 BE76  CBD0 7DEF 8106 AAFC 390E

* remotes/jnsnow/tags/bitmaps-pull-request:
  blockdev: acquire aio_context for bitmap add/remove
  block/dirty-bitmap: Documentation and Comment fixups
  dirty-bitmap: Expose persistent flag to 'query-block'

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 15 insertions, 6 deletions

diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c
index 00ea36f554..c6d4acebfa 100644
--- a/block/dirty-bitmap.c
+++ b/block/dirty-bitmap.c
@@ -29,12 +29,20 @@
 #include "block/blockjob.h"
 
 /**
- * A BdrvDirtyBitmap can be in three possible states:
- * (1) successor is NULL and disabled is false: full r/w mode
- * (2) successor is NULL and disabled is true: read only mode ("disabled")
- * (3) successor is set: frozen mode.
- *     A frozen bitmap cannot be renamed, deleted, anonymized, cleared, set,
- *     or enabled. A frozen bitmap can only abdicate() or reclaim().
+ * A BdrvDirtyBitmap can be in four possible user-visible states:
+ * (1) Active:   successor is NULL, and disabled is false: full r/w mode
+ * (2) Disabled: successor is NULL, and disabled is true: qualified r/w mode,
+ *               guest writes are dropped, but monitor writes are possible,
+ *               through commands like merge and clear.
+ * (3) Frozen:   successor is not NULL.
+ *               A frozen bitmap cannot be renamed, deleted, cleared, set,
+ *               enabled, merged to, etc. A frozen bitmap can only abdicate()
+ *               or reclaim().
+ *               In this state, the anonymous successor bitmap may be either
+ *               Active and recording writes from the guest (e.g. backup jobs),
+ *               but it can be Disabled and not recording writes.
+ * (4) Locked:   Whether Active or Disabled, the user cannot modify this bitmap
+ *               in any way from the monitor.
  */
 struct BdrvDirtyBitmap {
     QemuMutex *mutex;
@@ -440,6 +448,7 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
         info->has_name = !!bm->name;
         info->name = g_strdup(bm->name);
         info->status = bdrv_dirty_bitmap_status(bm);
+        info->persistent = bm->persistent;
         entry->value = info;
         *plist = entry;
         plist = &entry->next;