block: Convert bdrv_io_unplug() to co_wrapper

BlockDriver->bdrv_io_unplug is categorized as IO callback, and it
currently doesn't run in a coroutine. We should let it take a graph
rdlock since the callback traverses the block nodes graph, which however
is only possible in a coroutine.

The only caller of this function is blk_io_unplug(), therefore make
blk_io_unplug() a co_wrapper, so that we're always running in a
coroutine where the lock can be taken.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230113204212.359076-4-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

5 files changed, 15 insertions, 15 deletions

diff --git a/block/blkio.c b/block/blkio.c
index 6ad86b23d1..bd53d90d58 100644
--- a/block/blkio.c
+++ b/block/blkio.c
@@ -479,7 +479,7 @@ static int coroutine_fn blkio_co_pwrite_zeroes(BlockDriverState *bs,
     return cod.ret;
 }
 
-static void blkio_io_unplug(BlockDriverState *bs)
+static void coroutine_fn blkio_co_io_unplug(BlockDriverState *bs)
 {
     BDRVBlkioState *s = bs->opaque;
 
@@ -1008,7 +1008,7 @@ static void blkio_refresh_limits(BlockDriverState *bs, Error **errp)
         .bdrv_co_pwritev         = blkio_co_pwritev, \
         .bdrv_co_flush_to_disk   = blkio_co_flush, \
         .bdrv_co_pwrite_zeroes   = blkio_co_pwrite_zeroes, \
-        .bdrv_io_unplug          = blkio_io_unplug, \
+        .bdrv_co_io_unplug       = blkio_co_io_unplug, \
         .bdrv_refresh_limits     = blkio_refresh_limits, \
         .bdrv_register_buf       = blkio_register_buf, \
         .bdrv_unregister_buf     = blkio_unregister_buf, \
diff --git a/block/block-backend.c b/block/block-backend.c
index d10998fe19..e9cc7d291e 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -2325,13 +2325,13 @@ void coroutine_fn blk_co_io_plug(BlockBackend *blk)
     }
 }
 
-void blk_io_unplug(BlockBackend *blk)
+void coroutine_fn blk_co_io_unplug(BlockBackend *blk)
 {
     BlockDriverState *bs = blk_bs(blk);
     IO_CODE();
 
     if (bs) {
-        bdrv_io_unplug(bs);
+        bdrv_co_io_unplug(bs);
     }
 }
 
diff --git a/block/file-posix.c b/block/file-posix.c
index 6a5f8d6747..3b112095a4 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -2149,7 +2149,7 @@ static void coroutine_fn raw_co_io_plug(BlockDriverState *bs)
 #endif
 }
 
-static void raw_aio_unplug(BlockDriverState *bs)
+static void coroutine_fn raw_co_io_unplug(BlockDriverState *bs)
 {
     BDRVRawState __attribute__((unused)) *s = bs->opaque;
 #ifdef CONFIG_LINUX_AIO
@@ -3318,7 +3318,7 @@ BlockDriver bdrv_file = {
     .bdrv_co_copy_range_to  = raw_co_copy_range_to,
     .bdrv_refresh_limits = raw_refresh_limits,
     .bdrv_co_io_plug        = raw_co_io_plug,
-    .bdrv_io_unplug = raw_aio_unplug,
+    .bdrv_co_io_unplug      = raw_co_io_unplug,
     .bdrv_attach_aio_context = raw_aio_attach_aio_context,
 
     .bdrv_co_truncate = raw_co_truncate,
@@ -3690,7 +3690,7 @@ static BlockDriver bdrv_host_device = {
     .bdrv_co_copy_range_to  = raw_co_copy_range_to,
     .bdrv_refresh_limits = raw_refresh_limits,
     .bdrv_co_io_plug        = raw_co_io_plug,
-    .bdrv_io_unplug = raw_aio_unplug,
+    .bdrv_co_io_unplug      = raw_co_io_unplug,
     .bdrv_attach_aio_context = raw_aio_attach_aio_context,
 
     .bdrv_co_truncate       = raw_co_truncate,
@@ -3814,7 +3814,7 @@ static BlockDriver bdrv_host_cdrom = {
     .bdrv_co_flush_to_disk  = raw_co_flush_to_disk,
     .bdrv_refresh_limits = raw_refresh_limits,
     .bdrv_co_io_plug        = raw_co_io_plug,
-    .bdrv_io_unplug = raw_aio_unplug,
+    .bdrv_co_io_unplug      = raw_co_io_unplug,
     .bdrv_attach_aio_context = raw_aio_attach_aio_context,
 
     .bdrv_co_truncate    = raw_co_truncate,
@@ -3944,7 +3944,7 @@ static BlockDriver bdrv_host_cdrom = {
     .bdrv_co_flush_to_disk  = raw_co_flush_to_disk,
     .bdrv_refresh_limits = raw_refresh_limits,
     .bdrv_co_io_plug        = raw_co_io_plug,
-    .bdrv_io_unplug = raw_aio_unplug,
+    .bdrv_co_io_unplug      = raw_co_io_unplug,
     .bdrv_attach_aio_context = raw_aio_attach_aio_context,
 
     .bdrv_co_truncate    = raw_co_truncate,
diff --git a/block/io.c b/block/io.c
index 00bab27d34..d988053e4e 100644
--- a/block/io.c
+++ b/block/io.c
@@ -3154,7 +3154,7 @@ void coroutine_fn bdrv_co_io_plug(BlockDriverState *bs)
     }
 }
 
-void bdrv_io_unplug(BlockDriverState *bs)
+void coroutine_fn bdrv_co_io_unplug(BlockDriverState *bs)
 {
     BdrvChild *child;
     IO_CODE();
@@ -3162,13 +3162,13 @@ void bdrv_io_unplug(BlockDriverState *bs)
     assert(bs->io_plugged);
     if (qatomic_fetch_dec(&bs->io_plugged) == 1) {
         BlockDriver *drv = bs->drv;
-        if (drv && drv->bdrv_io_unplug) {
-            drv->bdrv_io_unplug(bs);
+        if (drv && drv->bdrv_co_io_unplug) {
+            drv->bdrv_co_io_unplug(bs);
         }
     }
 
     QLIST_FOREACH(child, &bs->children, next) {
-        bdrv_io_unplug(child->bs);
+        bdrv_co_io_unplug(child->bs);
     }
 }
 
diff --git a/block/nvme.c b/block/nvme.c
index 4c32584f07..1fe6f98925 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -1574,7 +1574,7 @@ static void coroutine_fn nvme_co_io_plug(BlockDriverState *bs)
     s->plugged = true;
 }
 
-static void nvme_aio_unplug(BlockDriverState *bs)
+static void coroutine_fn nvme_co_io_unplug(BlockDriverState *bs)
 {
     BDRVNVMeState *s = bs->opaque;
     assert(s->plugged);
@@ -1665,7 +1665,7 @@ static BlockDriver bdrv_nvme = {
     .bdrv_attach_aio_context  = nvme_attach_aio_context,
 
     .bdrv_co_io_plug          = nvme_co_io_plug,
-    .bdrv_io_unplug           = nvme_aio_unplug,
+    .bdrv_co_io_unplug        = nvme_co_io_unplug,
 
     .bdrv_register_buf        = nvme_register_buf,
     .bdrv_unregister_buf      = nvme_unregister_buf,