block: introduce bdrv_activate

This function is currently just a wrapper for bdrv_invalidate_cache(),
but in future will contain the code of bdrv_co_invalidate_cache() that
has to always be protected by BQL, and leave the rest in the I/O
coroutine.

Replace all bdrv_invalidate_cache() invokations with bdrv_activate().

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220209105452.1694545-4-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block.c

@@ -6393,6 +6393,11 @@ void bdrv_init_with_whitelist(void)
     bdrv_init();
 }
 
+int bdrv_activate(BlockDriverState *bs, Error **errp)
+{
+    return bdrv_invalidate_cache(bs, errp);
+}
+
 int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp)
 {
     BdrvChild *child, *parent;
@@ -6478,7 +6483,7 @@ void bdrv_invalidate_cache_all(Error **errp)
         int ret;
 
         aio_context_acquire(aio_context);
-        ret = bdrv_invalidate_cache(bs, errp);
+        ret = bdrv_activate(bs, errp);
         aio_context_release(aio_context);
         if (ret < 0) {
             bdrv_next_cleanup(&it);

block/block-backend.c

@@ -1889,7 +1889,7 @@ void blk_invalidate_cache(BlockBackend *blk, Error **errp)
         return;
     }
 
-    bdrv_invalidate_cache(bs, errp);
+    bdrv_activate(bs, errp);
 }
 
 bool blk_is_inserted(BlockBackend *blk)

block/export/export.c

@@ -139,7 +139,7 @@ BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
      * access since the export could be available before migration handover.
      * ctx was acquired in the caller.
      */
-    bdrv_invalidate_cache(bs, NULL);
+    bdrv_activate(bs, NULL);
 
     perm = BLK_PERM_CONSISTENT_READ;
     if (export->writable) {

block/parallels.c

@@ -873,7 +873,7 @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
     s->bat_dirty_bmap =
         bitmap_new(DIV_ROUND_UP(s->header_size, s->bat_dirty_block));
 
-    /* Disable migration until bdrv_invalidate_cache method is added */
+    /* Disable migration until bdrv_activate method is added */
     error_setg(&s->migration_blocker, "The Parallels format used by node '%s' "
                "does not support live migration",
                bdrv_get_device_or_node_name(bs));

include/block/block.h

@@ -494,6 +494,7 @@ int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf);
 int generated_co_wrapper bdrv_invalidate_cache(BlockDriverState *bs,
                                                Error **errp);
 void bdrv_invalidate_cache_all(Error **errp);
+int bdrv_activate(BlockDriverState *bs, Error **errp);
 int bdrv_inactivate_all(void);
 
 /* Ensure contents are flushed to disk.  */

tests/unit/test-block-iothread.c

@@ -282,7 +282,7 @@ static void test_sync_op_check(BdrvChild *c)
 static void test_sync_op_invalidate_cache(BdrvChild *c)
 {
     /* Early success: Image is not inactive */
-    bdrv_invalidate_cache(c->bs, NULL);
+    bdrv_activate(c->bs, NULL);
 }