@@ -246,7 +246,9 @@ bdrv_attach_child(BlockDriverState *parent_bs,
BdrvChildRole child_role,
Error **errp);
-bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
+bool GRAPH_RDLOCK
+bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
+
void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);
void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason);
void bdrv_op_block_all(BlockDriverState *bs, Error *reason);
@@ -7250,8 +7250,6 @@ bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp)
BdrvOpBlocker *blocker;
GLOBAL_STATE_CODE();
- assume_graph_lock(); /* FIXME */
-
assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX);
if (!QLIST_EMPTY(&bs->op_blockers[op])) {
blocker = QLIST_FIRST(&bs->op_blockers[op]);
@@ -2388,6 +2388,7 @@ bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp)
{
BlockDriverState *bs = blk_bs(blk);
GLOBAL_STATE_CODE();
+ GRAPH_RDLOCK_GUARD_MAINLOOP();
if (!bs) {
return false;
@@ -434,6 +434,7 @@ int bdrv_commit(BlockDriverState *bs)
Error *local_err = NULL;
GLOBAL_STATE_CODE();
+ GRAPH_RDLOCK_GUARD_MAINLOOP();
if (!drv)
return -ENOMEDIUM;
@@ -144,6 +144,9 @@ void hmp_drive_del(Monitor *mon, const QDict *qdict)
AioContext *aio_context;
Error *local_err = NULL;
+ GLOBAL_STATE_CODE();
+ GRAPH_RDLOCK_GUARD_MAINLOOP();
+
bs = bdrv_find_node(id);
if (bs) {
qmp_blockdev_del(id, &local_err);
@@ -169,14 +169,16 @@ void qmp_blockdev_close_tray(const char *device,
}
}
-static void blockdev_remove_medium(const char *device, const char *id,
- Error **errp)
+static void GRAPH_UNLOCKED
+blockdev_remove_medium(const char *device, const char *id, Error **errp)
{
BlockBackend *blk;
BlockDriverState *bs;
AioContext *aio_context;
bool has_attached_device;
+ GLOBAL_STATE_CODE();
+
blk = qmp_get_blk(device, id, errp);
if (!blk) {
return;
@@ -205,9 +207,12 @@ static void blockdev_remove_medium(const char *device, const char *id,
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
+ bdrv_graph_rdlock_main_loop();
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_EJECT, errp)) {
+ bdrv_graph_rdunlock_main_loop();
goto out;
}
+ bdrv_graph_rdunlock_main_loop();
blk_remove_bs(blk);
@@ -1696,9 +1696,12 @@ static void drive_backup_action(DriveBackup *backup,
}
/* Early check to avoid creating target */
+ bdrv_graph_rdlock_main_loop();
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_BACKUP_SOURCE, errp)) {
+ bdrv_graph_rdunlock_main_loop();
goto out;
}
+ bdrv_graph_rdunlock_main_loop();
flags = bs->open_flags | BDRV_O_RDWR;
@@ -2360,10 +2363,13 @@ void coroutine_fn qmp_block_resize(const char *device, const char *node_name,
return;
}
+ bdrv_graph_co_rdlock();
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_RESIZE, NULL)) {
error_setg(errp, QERR_DEVICE_IN_USE, device);
+ bdrv_graph_co_rdunlock();
return;
}
+ bdrv_graph_co_rdunlock();
blk = blk_co_new_with_bs(bs, BLK_PERM_RESIZE, BLK_PERM_ALL, errp);
if (!blk) {
@@ -2487,13 +2493,16 @@ void qmp_block_stream(const char *job_id, const char *device,
* Check for op blockers in the whole chain between bs and base (or bottom)
*/
iter_end = bottom ? bdrv_filter_or_cow_bs(bottom_bs) : base_bs;
+ bdrv_graph_rdlock_main_loop();
for (iter = bs; iter && iter != iter_end;
iter = bdrv_filter_or_cow_bs(iter))
{
if (bdrv_op_is_blocked(iter, BLOCK_OP_TYPE_STREAM, errp)) {
+ bdrv_graph_rdunlock_main_loop();
goto out;
}
}
+ bdrv_graph_rdunlock_main_loop();
/* if we are streaming the entire chain, the result will have no backing
* file, and specifying one is therefore an error */
@@ -3021,9 +3030,12 @@ void qmp_drive_mirror(DriveMirror *arg, Error **errp)
}
/* Early check to avoid creating target */
+ bdrv_graph_rdlock_main_loop();
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_MIRROR_SOURCE, errp)) {
+ bdrv_graph_rdunlock_main_loop();
return;
}
+ bdrv_graph_rdunlock_main_loop();
aio_context = bdrv_get_aio_context(bs);
aio_context_acquire(aio_context);
@@ -3409,9 +3421,12 @@ void qmp_change_backing_file(const char *device,
/* even though we are not necessarily operating on bs, we need it to
* determine if block ops are currently prohibited on the chain */
+ bdrv_graph_rdlock_main_loop();
if (bdrv_op_is_blocked(bs, BLOCK_OP_TYPE_CHANGE, errp)) {
+ bdrv_graph_rdunlock_main_loop();
goto out;
}
+ bdrv_graph_rdunlock_main_loop();
/* final sanity check */
if (!bdrv_chain_contains(bs, image_bs)) {
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_op_is_blocked() need to hold a reader lock for the graph because it calls bdrv_get_device_or_node_name(), which accesses the parents list of a node. Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-global-state.h | 4 +++- block.c | 2 -- block/block-backend.c | 1 + block/commit.c | 1 + block/monitor/block-hmp-cmds.c | 3 +++ block/qapi-sysemu.c | 9 +++++++-- blockdev.c | 15 +++++++++++++++ 7 files changed, 30 insertions(+), 5 deletions(-)