block-coroutine-wrapper: Add no_co_wrapper_bdrv_rdlock functions

Add a new wrapper type for GRAPH_RDLOCK functions that should be called
from coroutine context.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230929145157.45443-3-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 16:51:37 +02:00
parent 903df115aa
commit e84c07bc73
2 changed files with 12 additions and 5 deletions

View File

@ -66,13 +66,16 @@
* function. The coroutine yields after scheduling the BH and is reentered when
* the wrapped function returns.
*
* A no_co_wrapper_bdrv_wrlock function is a no_co_wrapper function that
* automatically takes the graph wrlock when calling the wrapped function.
* A no_co_wrapper_bdrv_rdlock function is a no_co_wrapper function that
* automatically takes the graph rdlock when calling the wrapped function. In
* the same way, no_co_wrapper_bdrv_wrlock functions automatically take the
* graph wrlock.
*
* If the first parameter of the function is a BlockDriverState, BdrvChild or
* BlockBackend pointer, the AioContext lock for it is taken in the wrapper.
*/
#define no_co_wrapper
#define no_co_wrapper_bdrv_rdlock
#define no_co_wrapper_bdrv_wrlock
#include "block/blockjob.h"

View File

@ -87,8 +87,9 @@ class FuncDecl:
raise ValueError(f"Invalid no_co function name: {self.name}")
if not self.create_only_co:
raise ValueError(f"no_co function can't be mixed: {self.name}")
if self.graph_rdlock:
raise ValueError(f"no_co function can't be rdlock: {self.name}")
if self.graph_rdlock and self.graph_wrlock:
raise ValueError("function can't be both rdlock and wrlock: "
f"{self.name}")
self.target_name = f'{subsystem}_{subname}'
self.ctx = self.gen_ctx()
@ -256,7 +257,10 @@ def gen_no_co_wrapper(func: FuncDecl) -> str:
graph_lock=''
graph_unlock=''
if func.graph_wrlock:
if func.graph_rdlock:
graph_lock=' bdrv_graph_rdlock_main_loop();'
graph_unlock=' bdrv_graph_rdunlock_main_loop();'
elif func.graph_wrlock:
graph_lock=' bdrv_graph_wrlock(NULL);'
graph_unlock=' bdrv_graph_wrunlock();'