From 1808e560396872173f787f8e338e9837a4c3d626 Mon Sep 17 00:00:00 2001
From: Kevin Wolf <kwolf@redhat.com>
Date: Fri, 18 Nov 2022 18:41:00 +0100
Subject: [PATCH 18/31] block: Inline bdrv_drain_invoke()

RH-Author: Stefano Garzarella <sgarzare@redhat.com>
RH-MergeRequest: 135: block: Simplify drain to prevent QEMU from crashing during snapshot
RH-Bugzilla: 2155112
RH-Acked-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
RH-Acked-by: Hanna Czenczek <hreitz@redhat.com>
RH-Acked-by: Kevin Wolf <kwolf@redhat.com>
RH-Commit: [6/16] 2c7473a36360eb43d94b967deb12308cb5ea0d3b (sgarzarella/qemu-kvm-c-9-s)

bdrv_drain_invoke() has now two entirely separate cases that share no
code any more and are selected depending on a bool parameter. Each case
has only one caller. Just inline the function.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20221118174110.55183-6-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
(cherry picked from commit c7bc05f78ab31fb02fc9635f60b9bd22efc8d121)
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
---
 block/io.c | 23 ++++++-----------------
 1 file changed, 6 insertions(+), 17 deletions(-)

diff --git a/block/io.c b/block/io.c
index f4ca62b034..a25103be6f 100644
--- a/block/io.c
+++ b/block/io.c
@@ -242,21 +242,6 @@ typedef struct {
     bool ignore_bds_parents;
 } BdrvCoDrainData;
 
-/* Recursively call BlockDriver.bdrv_drain_begin/end callbacks */
-static void bdrv_drain_invoke(BlockDriverState *bs, bool begin)
-{
-    if (!bs->drv || (begin && !bs->drv->bdrv_drain_begin) ||
-            (!begin && !bs->drv->bdrv_drain_end)) {
-        return;
-    }
-
-    if (begin) {
-        bs->drv->bdrv_drain_begin(bs);
-    } else {
-        bs->drv->bdrv_drain_end(bs);
-    }
-}
-
 /* Returns true if BDRV_POLL_WHILE() should go into a blocking aio_poll() */
 bool bdrv_drain_poll(BlockDriverState *bs, bool recursive,
                      BdrvChild *ignore_parent, bool ignore_bds_parents)
@@ -390,7 +375,9 @@ void bdrv_do_drained_begin_quiesce(BlockDriverState *bs,
     }
 
     bdrv_parent_drained_begin(bs, parent, ignore_bds_parents);
-    bdrv_drain_invoke(bs, true);
+    if (bs->drv && bs->drv->bdrv_drain_begin) {
+        bs->drv->bdrv_drain_begin(bs);
+    }
 }
 
 static void bdrv_do_drained_begin(BlockDriverState *bs, bool recursive,
@@ -461,7 +448,9 @@ static void bdrv_do_drained_end(BlockDriverState *bs, bool recursive,
     assert(bs->quiesce_counter > 0);
 
     /* Re-enable things in child-to-parent order */
-    bdrv_drain_invoke(bs, false);
+    if (bs->drv && bs->drv->bdrv_drain_end) {
+        bs->drv->bdrv_drain_end(bs);
+    }
     bdrv_parent_drained_end(bs, parent, ignore_bds_parents);
 
     old_quiesce_counter = qatomic_fetch_dec(&bs->quiesce_counter);
-- 
2.31.1