Introduce .pre_run() job callback. This cb will run in job_start,
before the coroutine is created and runs run() in the job aiocontext.
Therefore, .pre_run() always runs in the main loop.
We can use this function together with clean() cb to replace
bdrv_child_refresh_perms in block_crypto_amend_options_generic_luks(),
since that function can also be called from an iothread via
.bdrv_co_amend().
In addition, doing so we check for permissions in all bdrv
in amend, not only crypto.
.pre_run() and .clean() take care of calling bdrv_amend_pre_run()
and bdrv_amend_clean() respectively, to set up driver-specific flags
and allow the crypto driver to temporarly provide the WRITE
perm to qcrypto_block_amend_options().
.pre_run() is not yet invoked by job_start, but .clean() is.
This is not a problem, since it will just be a redundant check
and crypto will have the update->keys flag == false anyways.
Signed-off-by: Emanuele Giuseppe Esposito <eespo...@redhat.com>
---
block/amend.c | 33 +++++++++++++++++++++++++++++++++
include/qemu/job.h | 9 +++++++++
2 files changed, 42 insertions(+)
diff --git a/block/amend.c b/block/amend.c
index 392df9ef83..1618fd05a6 100644
--- a/block/amend.c
+++ b/block/amend.c
@@ -53,10 +53,43 @@ static int coroutine_fn blockdev_amend_run(Job *job, Error
**errp)
return ret;
}
+static int blockdev_amend_refresh_perms(Job *job, Error **errp)
+{
+ BlockdevAmendJob *s = container_of(job, BlockdevAmendJob, common);
+ return bdrv_child_refresh_perms(s->bs, s->bs->file, errp);
+}
+
+static int blockdev_amend_pre_run(Job *job, Error **errp)
+{
+ BlockdevAmendJob *s = container_of(job, BlockdevAmendJob, common);
+
+ if (s->bs->drv->bdrv_amend_pre_run) {
+ s->bs->drv->bdrv_amend_pre_run(s->bs);
+ }
+ return blockdev_amend_refresh_perms(job, errp);
+}
+
+static void blockdev_amend_clean(Job *job)
+{
+ BlockdevAmendJob *s = container_of(job, BlockdevAmendJob, common);
+ Error *errp = NULL;
+
+ if (s->bs->drv->bdrv_amend_clean) {
+ s->bs->drv->bdrv_amend_clean(s->bs);
+ }
+
+ blockdev_amend_refresh_perms(job, &errp);
+ if (errp) {
+ error_report_err(errp);
+ }
+}
+
static const JobDriver blockdev_amend_job_driver = {
.instance_size = sizeof(BlockdevAmendJob),
.job_type = JOB_TYPE_AMEND,
.run = blockdev_amend_run,
+ .pre_run = blockdev_amend_pre_run,
+ .clean = blockdev_amend_clean,
};
void qmp_x_blockdev_amend(const char *job_id,
diff --git a/include/qemu/job.h b/include/qemu/job.h
index 4ea7a4a0cd..915ceff425 100644
--- a/include/qemu/job.h
+++ b/include/qemu/job.h
@@ -223,6 +223,15 @@ struct JobDriver {
* the GS API.
*/
+ /**
+ * Called in the Main Loop context, before the job coroutine
+ * is started in the job aiocontext. Useful to perform operations
+ * that needs to be done under BQL (like permissions setup).
+ * On success, it returns 0. Otherwise the job failed to initialize
+ * and won't start.
+ */
+ int (*pre_run)(Job *job, Error **errp);
+
/**
* Called when the job is resumed by the user (i.e. user_paused becomes
* false). .user_resume is called before .resume.
--
2.31.1
