block: Mark bdrv_get_specific_info() and callers GRAPH_RDLOCK

This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_get_specific_info() need to hold a reader lock for the graph. This removes an assume_graph_lock() call in vmdk's implementation. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-ID: <20230929145157.45443-20-kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
qemu · Oct 12, 2023 · 3574499 · 3574499
1 parent 018f9de
commit 3574499
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Showing 4 changed files with 10 additions and 8 deletions.
diff --git a/block/vmdk.c b/block/vmdk.c
@@ -2990,16 +2990,14 @@ vmdk_co_check(BlockDriverState *bs, BdrvCheckResult *result, BdrvCheckMode fix)
     return ret;
 }
 
-static ImageInfoSpecific *vmdk_get_specific_info(BlockDriverState *bs,
-                                                 Error **errp)
+static ImageInfoSpecific * GRAPH_RDLOCK
+vmdk_get_specific_info(BlockDriverState *bs, Error **errp)
 {
     int i;
     BDRVVmdkState *s = bs->opaque;
     ImageInfoSpecific *spec_info = g_new0(ImageInfoSpecific, 1);
     VmdkExtentInfoList **tail;
 
-    assume_graph_lock(); /* FIXME */
-
     *spec_info = (ImageInfoSpecific){
         .type = IMAGE_INFO_SPECIFIC_KIND_VMDK,
         .u = {

diff --git a/include/block/block-io.h b/include/block/block-io.h
@@ -198,8 +198,9 @@ bdrv_co_get_info(BlockDriverState *bs, BlockDriverInfo *bdi);
 int co_wrapper_mixed_bdrv_rdlock
 bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi);
 
-ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs,
-                                          Error **errp);
+ImageInfoSpecific * GRAPH_RDLOCK
+bdrv_get_specific_info(BlockDriverState *bs, Error **errp);
+
 BlockStatsSpecific *bdrv_get_specific_stats(BlockDriverState *bs);
 void bdrv_round_to_subclusters(BlockDriverState *bs,
                                int64_t offset, int64_t bytes,

diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h
@@ -728,8 +728,8 @@ struct BlockDriver {
     int coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_co_get_info)(
         BlockDriverState *bs, BlockDriverInfo *bdi);
 
-    ImageInfoSpecific *(*bdrv_get_specific_info)(BlockDriverState *bs,
-                                                 Error **errp);
+    ImageInfoSpecific * GRAPH_RDLOCK_PTR (*bdrv_get_specific_info)(
+        BlockDriverState *bs, Error **errp);
     BlockStatsSpecific *(*bdrv_get_specific_stats)(BlockDriverState *bs);
 
     int coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_co_save_vmstate)(

diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
@@ -2037,6 +2037,9 @@ static int info_f(BlockBackend *blk, int argc, char **argv)
     char s1[64], s2[64];
     int ret;
 
+    GLOBAL_STATE_CODE();
+    GRAPH_RDLOCK_GUARD_MAINLOOP();
+
     if (bs->drv && bs->drv->format_name) {
         printf("format name: %s\n", bs->drv->format_name);
     }