[PATCH v5 1/7] block: return error-code from bdrv_invalidate_cache

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

This is the only coroutine wrapper from block.c and block/io.c which
doesn't return value, so let's convert it to the common behavior, to
simplify moving to generated coroutine wrappers in further commit.

Also, bdrv_invalidate_cache is a void function, returning error only
through **errp parameter, which considered to be bad practice, as it
forces callers to define and propagate local_err variable, so
conversion is good anyway.

This patch leaves convertion of .bdrv_co_invalidate_cache() driver
callbacks and bdrv_invalidate_cache_all() for another-day refactoring.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 include/block/block.h |  2 +-
 block.c               | 32 ++++++++++++++++++--------------
 2 files changed, 19 insertions(+), 15 deletions(-)

diff --git a/include/block/block.h b/include/block/block.h
index 25e299605e..46965a7780 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -464,7 +464,7 @@ void bdrv_aio_cancel_async(BlockAIOCB *acb);
 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf);
 
 /* Invalidate any cached metadata used by image formats */
-void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp);
+int bdrv_invalidate_cache(BlockDriverState *bs, Error **errp);
 void bdrv_invalidate_cache_all(Error **errp);
 int bdrv_inactivate_all(void);
 
diff --git a/block.c b/block.c
index 8416376c9b..b01551f21c 100644
--- a/block.c
+++ b/block.c
@@ -5643,8 +5643,8 @@ void bdrv_init_with_whitelist(void)
     bdrv_init();
 }
 
-static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
-                                                  Error **errp)
+static int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
+                                                 Error **errp)
 {
     BdrvChild *child, *parent;
     uint64_t perm, shared_perm;
@@ -5653,14 +5653,14 @@ static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
     BdrvDirtyBitmap *bm;
 
     if (!bs->drv)  {
-        return;
+        return -ENOMEDIUM;
     }
 
     QLIST_FOREACH(child, &bs->children, next) {
         bdrv_co_invalidate_cache(child->bs, &local_err);
         if (local_err) {
             error_propagate(errp, local_err);
-            return;
+            return -EINVAL;
         }
     }
 
@@ -5684,7 +5684,7 @@ static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
         if (ret < 0) {
             bs->open_flags |= BDRV_O_INACTIVE;
             error_propagate(errp, local_err);
-            return;
+            return ret;
         }
         bdrv_set_perm(bs, perm, shared_perm);
 
@@ -5693,7 +5693,7 @@ static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
             if (local_err) {
                 bs->open_flags |= BDRV_O_INACTIVE;
                 error_propagate(errp, local_err);
-                return;
+                return -EINVAL;
             }
         }
 
@@ -5705,7 +5705,7 @@ static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
         if (ret < 0) {
             bs->open_flags |= BDRV_O_INACTIVE;
             error_setg_errno(errp, -ret, "Could not refresh total sector count");
-            return;
+            return ret;
         }
     }
 
@@ -5715,27 +5715,30 @@ static void coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs,
             if (local_err) {
                 bs->open_flags |= BDRV_O_INACTIVE;
                 error_propagate(errp, local_err);
-                return;
+                return -EINVAL;
             }
         }
     }
+
+    return 0;
 }
 
 typedef struct InvalidateCacheCo {
     BlockDriverState *bs;
     Error **errp;
     bool done;
+    int ret;
 } InvalidateCacheCo;
 
 static void coroutine_fn bdrv_invalidate_cache_co_entry(void *opaque)
 {
     InvalidateCacheCo *ico = opaque;
-    bdrv_co_invalidate_cache(ico->bs, ico->errp);
+    ico->ret = bdrv_co_invalidate_cache(ico->bs, ico->errp);
     ico->done = true;
     aio_wait_kick();
 }
 
-void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp)
+int bdrv_invalidate_cache(BlockDriverState *bs, Error **errp)
 {
     Coroutine *co;
     InvalidateCacheCo ico = {
@@ -5752,22 +5755,23 @@ void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp)
         bdrv_coroutine_enter(bs, co);
         BDRV_POLL_WHILE(bs, !ico.done);
     }
+
+    return ico.ret;
 }
 
 void bdrv_invalidate_cache_all(Error **errp)
 {
     BlockDriverState *bs;
-    Error *local_err = NULL;
     BdrvNextIterator it;
 
     for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
         AioContext *aio_context = bdrv_get_aio_context(bs);
+        int ret;
 
         aio_context_acquire(aio_context);
-        bdrv_invalidate_cache(bs, &local_err);
+        ret = bdrv_invalidate_cache(bs, errp);
         aio_context_release(aio_context);
-        if (local_err) {
-            error_propagate(errp, local_err);
+        if (ret < 0) {
             bdrv_next_cleanup(&it);
             return;
         }
-- 
2.21.0