Add reference count to block job, meanwhile move the ownership of the
reference to job->bs from the caller (which is released in two
completion callbacks) to the block job itself. It is necessary for
block_job_complete_sync to work, because block job shouldn't live longer
than its bs, as asserted in bdrv_delete.
Now block_job_complete_sync can be simplified.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id:
1446765200-3054-6-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
s->dirty_bitmap = bdrv_create_dirty_bitmap(bs, granularity, NULL, errp);
if (!s->dirty_bitmap) {
g_free(s->replaces);
- block_job_release(bs);
+ block_job_unref(&s->common);
return;
}
BlockDriverState *bs;
} BDRVPutRefBH;
-static void bdrv_put_ref_bh(void *opaque)
-{
- BDRVPutRefBH *s = opaque;
-
- bdrv_unref(s->bs);
- qemu_bh_delete(s->bh);
- g_free(s);
-}
-
-/*
- * Release a BDS reference in a BH
- *
- * It is not safe to use bdrv_unref() from a callback function when the callers
- * still need the BlockDriverState. In such cases we schedule a BH to release
- * the reference.
- */
-static void bdrv_put_ref_bh_schedule(BlockDriverState *bs)
-{
- BDRVPutRefBH *s;
-
- s = g_new(BDRVPutRefBH, 1);
- s->bh = qemu_bh_new(bdrv_put_ref_bh, s);
- s->bs = bs;
- qemu_bh_schedule(s->bh);
-}
-
static int parse_block_error_action(const char *buf, bool is_read, Error **errp)
{
if (!strcmp(buf, "ignore")) {
} else {
block_job_event_completed(bs->job, msg);
}
-
- bdrv_put_ref_bh_schedule(bs);
}
void qmp_block_stream(const char *device,
job->cb = cb;
job->opaque = opaque;
job->busy = true;
+ job->refcnt = 1;
bs->job = job;
/* Only set speed when necessary to avoid NotSupported error */
block_job_set_speed(job, speed, &local_err);
if (local_err) {
- block_job_release(bs);
+ block_job_unref(job);
error_propagate(errp, local_err);
return NULL;
}
return job;
}
-void block_job_release(BlockDriverState *bs)
+void block_job_ref(BlockJob *job)
{
- BlockJob *job = bs->job;
+ ++job->refcnt;
+}
- bs->job = NULL;
- bdrv_op_unblock_all(bs, job->blocker);
- error_free(job->blocker);
- g_free(job->id);
- g_free(job);
+void block_job_unref(BlockJob *job)
+{
+ if (--job->refcnt == 0) {
+ job->bs->job = NULL;
+ bdrv_op_unblock_all(job->bs, job->blocker);
+ bdrv_unref(job->bs);
+ error_free(job->blocker);
+ g_free(job->id);
+ g_free(job);
+ }
}
void block_job_completed(BlockJob *job, int ret)
assert(bs->job == job);
job->cb(job->opaque, ret);
- block_job_release(bs);
+ block_job_unref(job);
}
void block_job_set_speed(BlockJob *job, int64_t speed, Error **errp)
/** The opaque value that is passed to the completion function. */
void *opaque;
+
+ /** Reference count of the block job */
+ int refcnt;
};
/**
void block_job_yield(BlockJob *job);
/**
- * block_job_release:
+ * block_job_ref:
+ * @bs: The block device.
+ *
+ * Grab a reference to the block job. Should be paired with block_job_unref.
+ */
+void block_job_ref(BlockJob *job);
+
+/**
+ * block_job_unref:
* @bs: The block device.
*
- * Release job resources when an error occurred or job completed.
+ * Release reference to the block job and release resources if it is the last
+ * reference.
*/
-void block_job_release(BlockDriverState *bs);
+void block_job_unref(BlockJob *job);
/**
* block_job_completed:
if (ret < 0) {
error_setg_errno(cbi->errp, -ret, "Block job failed");
}
-
- /* Drop this block job's reference */
- bdrv_unref(cbi->bs);
}
static void run_block_job(BlockJob *job, Error **errp)