[PATCH v2 3/3] block: drop BlockBackendRootState::read_only

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

Instead of keeping additional boolean field, let's store the
information in BDRV_O_RDWR bit of BlockBackendRootState::open_flags.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 include/block/block_int.h |  1 -
 block/block-backend.c     | 10 ++--------
 blockdev.c                |  3 +--
 3 files changed, 3 insertions(+), 11 deletions(-)

diff --git a/include/block/block_int.h b/include/block/block_int.h
index 09661a134b..057d88b1fc 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -1007,7 +1007,6 @@ struct BlockDriverState {
 
 struct BlockBackendRootState {
     int open_flags;
-    bool read_only;
     BlockdevDetectZeroesOptions detect_zeroes;
 };
 
diff --git a/block/block-backend.c b/block/block-backend.c
index 21b834e9df..d1a33a2c8e 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -1852,7 +1852,7 @@ bool blk_supports_write_perm(BlockBackend *blk)
     if (bs) {
         return !bdrv_is_read_only(bs);
     } else {
-        return !blk->root_state.read_only;
+        return blk->root_state.open_flags & BDRV_O_RDWR;
     }
 }
 
@@ -2269,7 +2269,6 @@ void blk_update_root_state(BlockBackend *blk)
     assert(blk->root);
 
     blk->root_state.open_flags    = blk->root->bs->open_flags;
-    blk->root_state.read_only     = bdrv_is_read_only(blk->root->bs);
     blk->root_state.detect_zeroes = blk->root->bs->detect_zeroes;
 }
 
@@ -2288,12 +2287,7 @@ bool blk_get_detect_zeroes_from_root_state(BlockBackend *blk)
  */
 int blk_get_open_flags_from_root_state(BlockBackend *blk)
 {
-    int bs_flags;
-
-    bs_flags = blk->root_state.read_only ? 0 : BDRV_O_RDWR;
-    bs_flags |= blk->root_state.open_flags & ~BDRV_O_RDWR;
-
-    return bs_flags;
+    return blk->root_state.open_flags;
 }
 
 BlockBackendRootState *blk_get_root_state(BlockBackend *blk)
diff --git a/blockdev.c b/blockdev.c
index 834c2304a1..f08192deda 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -583,8 +583,7 @@ static BlockBackend *blockdev_init(const char *file, QDict *bs_opts,
 
         blk = blk_new(qemu_get_aio_context(), 0, BLK_PERM_ALL);
         blk_rs = blk_get_root_state(blk);
-        blk_rs->open_flags    = bdrv_flags;
-        blk_rs->read_only     = read_only;
+        blk_rs->open_flags    = bdrv_flags | (read_only ? 0 : BDRV_O_RDWR);
         blk_rs->detect_zeroes = detect_zeroes;
 
         qobject_unref(bs_opts);
-- 
2.29.2