block: Mark bdrv_co_eject/lock_medium() and callers GRAPH_RDLOCK

This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_eject() and bdrv_co_lock_medium() need to hold a reader lock for
the graph.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-20-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

7 files changed, 23 insertions, 10 deletions

diff --git a/block.c b/block.c
index 738b42046c..1060194e8f 100644
--- a/block.c
+++ b/block.c
@@ -6849,6 +6849,7 @@ void coroutine_fn bdrv_co_eject(BlockDriverState *bs, bool eject_flag)
 {
     BlockDriver *drv = bs->drv;
     IO_CODE();
+    assert_bdrv_graph_readable();
 
     if (drv && drv->bdrv_co_eject) {
         drv->bdrv_co_eject(bs, eject_flag);
@@ -6863,6 +6864,7 @@ void coroutine_fn bdrv_co_lock_medium(BlockDriverState *bs, bool locked)
 {
     BlockDriver *drv = bs->drv;
     IO_CODE();
+    assert_bdrv_graph_readable();
     trace_bdrv_lock_medium(bs, locked);
 
     if (drv && drv->bdrv_co_lock_medium) {
diff --git a/block/block-backend.c b/block/block-backend.c
index 20af699f00..278b04ce69 100644
--- a/block/block-backend.c
+++ b/block/block-backend.c
@@ -2013,6 +2013,7 @@ void coroutine_fn blk_co_lock_medium(BlockBackend *blk, bool locked)
 {
     BlockDriverState *bs = blk_bs(blk);
     IO_CODE();
+    GRAPH_RDLOCK_GUARD();
 
     if (bs) {
         bdrv_co_lock_medium(bs, locked);
@@ -2024,6 +2025,7 @@ void coroutine_fn blk_co_eject(BlockBackend *blk, bool eject_flag)
     BlockDriverState *bs = blk_bs(blk);
     char *id;
     IO_CODE();
+    GRAPH_RDLOCK_GUARD();
 
     if (bs) {
         bdrv_co_eject(bs, eject_flag);
diff --git a/block/copy-on-read.c b/block/copy-on-read.c
index 78da353f88..20215cff93 100644
--- a/block/copy-on-read.c
+++ b/block/copy-on-read.c
@@ -213,13 +213,15 @@ cor_co_pwritev_compressed(BlockDriverState *bs, int64_t offset, int64_t bytes,
 }
 
 
-static void coroutine_fn cor_co_eject(BlockDriverState *bs, bool eject_flag)
+static void coroutine_fn GRAPH_RDLOCK
+cor_co_eject(BlockDriverState *bs, bool eject_flag)
 {
     bdrv_co_eject(bs->file->bs, eject_flag);
 }
 
 
-static void coroutine_fn cor_co_lock_medium(BlockDriverState *bs, bool locked)
+static void coroutine_fn GRAPH_RDLOCK
+cor_co_lock_medium(BlockDriverState *bs, bool locked)
 {
     bdrv_co_lock_medium(bs->file->bs, locked);
 }
diff --git a/block/filter-compress.c b/block/filter-compress.c
index 0dd5606410..c7d50a67a7 100644
--- a/block/filter-compress.c
+++ b/block/filter-compress.c
@@ -114,14 +114,14 @@ static void compress_refresh_limits(BlockDriverState *bs, Error **errp)
 }
 
 
-static void coroutine_fn
+static void coroutine_fn GRAPH_RDLOCK
 compress_co_eject(BlockDriverState *bs, bool eject_flag)
 {
     bdrv_co_eject(bs->file->bs, eject_flag);
 }
 
 
-static void coroutine_fn
+static void coroutine_fn GRAPH_RDLOCK
 compress_co_lock_medium(BlockDriverState *bs, bool locked)
 {
     bdrv_co_lock_medium(bs->file->bs, locked);
diff --git a/block/raw-format.c b/block/raw-format.c
index 646606e223..f4203d4806 100644
--- a/block/raw-format.c
+++ b/block/raw-format.c
@@ -405,12 +405,14 @@ raw_co_truncate(BlockDriverState *bs, int64_t offset, bool exact,
     return bdrv_co_truncate(bs->file, offset, exact, prealloc, flags, errp);
 }
 
-static void coroutine_fn raw_co_eject(BlockDriverState *bs, bool eject_flag)
+static void coroutine_fn GRAPH_RDLOCK
+raw_co_eject(BlockDriverState *bs, bool eject_flag)
 {
     bdrv_co_eject(bs->file->bs, eject_flag);
 }
 
-static void coroutine_fn raw_co_lock_medium(BlockDriverState *bs, bool locked)
+static void coroutine_fn GRAPH_RDLOCK
+raw_co_lock_medium(BlockDriverState *bs, bool locked)
 {
     bdrv_co_lock_medium(bs->file->bs, locked);
 }
diff --git a/include/block/block-io.h b/include/block/block-io.h
index 88db63492a..bf2748011e 100644
--- a/include/block/block-io.h
+++ b/include/block/block-io.h
@@ -148,8 +148,11 @@ int bdrv_get_flags(BlockDriverState *bs);
 bool coroutine_fn GRAPH_RDLOCK bdrv_co_is_inserted(BlockDriverState *bs);
 bool co_wrapper_bdrv_rdlock bdrv_is_inserted(BlockDriverState *bs);
 
-void coroutine_fn bdrv_co_lock_medium(BlockDriverState *bs, bool locked);
-void coroutine_fn bdrv_co_eject(BlockDriverState *bs, bool eject_flag);
+void coroutine_fn GRAPH_RDLOCK
+bdrv_co_lock_medium(BlockDriverState *bs, bool locked);
+
+void coroutine_fn GRAPH_RDLOCK
+bdrv_co_eject(BlockDriverState *bs, bool eject_flag);
 
 const char *bdrv_get_format_name(BlockDriverState *bs);
 
diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h
index b4a82269e5..30e6bd4909 100644
--- a/include/block/block_int-common.h
+++ b/include/block/block_int-common.h
@@ -714,8 +714,10 @@ struct BlockDriver {
     /* removable device specific */
     bool coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_co_is_inserted)(
         BlockDriverState *bs);
-    void coroutine_fn (*bdrv_co_eject)(BlockDriverState *bs, bool eject_flag);
-    void coroutine_fn (*bdrv_co_lock_medium)(BlockDriverState *bs, bool locked);
+    void coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_co_eject)(
+        BlockDriverState *bs, bool eject_flag);
+    void coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_co_lock_medium)(
+        BlockDriverState *bs, bool locked);
 
     /* to control generic scsi devices */
     BlockAIOCB *coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_aio_ioctl)(