OpenE2K/qemu-e2k
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block: Mark bdrv_primary_child() and callers GRAPH_RDLOCK

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This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_primary_child() need to hold a reader lock for the graph
because it accesses the children list of a node.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-12-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2023-09-29 16:51:46 +02:00
parent b7cfc7d58e
commit c0fc5123ad
3 changed files with 16 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
block.c
View File

@ -6692,7 +6692,8 @@ void coroutine_fn bdrv_co_debug_event(BlockDriverState *bs, BlkdebugEvent event)
bs->drv->bdrv_co_debug_event(bs, event);
}
static BlockDriverState *bdrv_find_debug_node(BlockDriverState *bs)
static BlockDriverState * GRAPH_RDLOCK
bdrv_find_debug_node(BlockDriverState *bs)
{
GLOBAL_STATE_CODE();
while (bs && bs->drv && !bs->drv->bdrv_debug_breakpoint) {
@ -6711,6 +6712,8 @@ int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
const char *tag)
{
GLOBAL_STATE_CODE();
GRAPH_RDLOCK_GUARD_MAINLOOP();
bs = bdrv_find_debug_node(bs);
if (bs) {
return bs->drv->bdrv_debug_breakpoint(bs, event, tag);
@ -6722,6 +6725,8 @@ int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag)
{
GLOBAL_STATE_CODE();
GRAPH_RDLOCK_GUARD_MAINLOOP();
bs = bdrv_find_debug_node(bs);
if (bs) {
return bs->drv->bdrv_debug_remove_breakpoint(bs, tag);
@ -6733,6 +6738,8 @@ int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag)
int bdrv_debug_resume(BlockDriverState *bs, const char *tag)
{
GLOBAL_STATE_CODE();
GRAPH_RDLOCK_GUARD_MAINLOOP();
while (bs && (!bs->drv || !bs->drv->bdrv_debug_resume)) {
bs = bdrv_primary_bs(bs);
}
@ -6747,6 +6754,8 @@ int bdrv_debug_resume(BlockDriverState *bs, const char *tag)
bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag)
{
GLOBAL_STATE_CODE();
GRAPH_RDLOCK_GUARD_MAINLOOP();
while (bs && bs->drv && !bs->drv->bdrv_debug_is_suspended) {
bs = bdrv_primary_bs(bs);
}

3
block/snapshot.c
View File

@ -311,7 +311,10 @@ int bdrv_snapshot_goto(BlockDriverState *bs,
* respective option (with the qdict_put_str() call above).
* Assert that .bdrv_open() has attached the right BDS as primary child.
*/
bdrv_graph_rdlock_main_loop();
assert(bdrv_primary_bs(bs) == fallback_bs);
bdrv_graph_rdunlock_main_loop();
bdrv_unref(fallback_bs);
return ret;
}

5
include/block/block_int-io.h
View File

@ -133,7 +133,7 @@ bdrv_refresh_total_sectors(BlockDriverState *bs, int64_t hint);
BdrvChild *bdrv_cow_child(BlockDriverState *bs);
BdrvChild *bdrv_filter_child(BlockDriverState *bs);
BdrvChild *bdrv_filter_or_cow_child(BlockDriverState *bs);
BdrvChild *bdrv_primary_child(BlockDriverState *bs);
BdrvChild * GRAPH_RDLOCK bdrv_primary_child(BlockDriverState *bs);
BlockDriverState *bdrv_skip_filters(BlockDriverState *bs);
BlockDriverState *bdrv_backing_chain_next(BlockDriverState *bs);
@ -155,7 +155,8 @@ static inline BlockDriverState *bdrv_filter_or_cow_bs(BlockDriverState *bs)
return child_bs(bdrv_filter_or_cow_child(bs));
}
static inline BlockDriverState *bdrv_primary_bs(BlockDriverState *bs)
static inline BlockDriverState * GRAPH_RDLOCK
bdrv_primary_bs(BlockDriverState *bs)
{
IO_CODE();
return child_bs(bdrv_primary_child(bs));