blockjob: Introduce reference count and fix reference to job->bs

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>
This commit is contained in:
Fam Zheng 2015-11-05 18:13:11 -05:00 committed by Kevin Wolf
parent b976ea3cf5
commit 18930ba3d1
5 changed files with 32 additions and 44 deletions

View file

@ -283,32 +283,6 @@ typedef struct {
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")) {
@ -2741,8 +2715,6 @@ static void block_job_cb(void *opaque, int ret)
} else {
block_job_event_completed(bs->job, msg);
}
bdrv_put_ref_bh_schedule(bs);
}
void qmp_block_stream(const char *device,