diff options
| author | Lars Ellenberg <lars.ellenberg@linbit.com> | 2012-09-03 14:08:35 +0200 |
|---|---|---|
| committer | Philipp Reisner <philipp.reisner@linbit.com> | 2012-11-09 14:11:37 +0100 |
| commit | 70f17b6bd18dfe33f40db7573baa663b866be6ba (patch) | |
| tree | 43e12531930774a6b1814a065441ca0ee1fce7df | |
| parent | 76590cd1fc338fd1c50f7121636db421deb8b881 (diff) | |
drbd: differentiate early and later "postponing" of requests
We use the RQ_POSTPONED flag to mark a request for several reasons.
It may be a conflicting request in a dual-primary setup,
where conflict detection and resolution on the peer decided that
this request needs to be re-submitted, it needs to re-enter
drbd_make_request() to fix the data divergence caused by these
conflicting, partially overlapping, quasi-simultaneous requests.
In this case we need to mark the corresponding area as out-of-sync,
before we call drbd_al_complete_io().
We also use the RQ_POSTPONED flag to just "push back" a request,
before even processing it, if IO is suspended for some reason.
In this case, as this request was neither submitted nor sent yet,
we must not touch the bitmap.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
| -rw-r--r-- | drivers/block/drbd/drbd_req.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index d1d17fcd9232..e307890e6afe 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c @@ -123,7 +123,14 @@ void drbd_req_destroy(struct kref *kref) * (local only or remote failed). * Other places where we set out-of-sync: * READ with local io-error */ - if (!(s & RQ_POSTPONED)) { + + /* There is a special case: + * we may notice late that IO was suspended, + * and postpone, or schedule for retry, a write, + * before it even was submitted or sent. + * In that case we do not want to touch the bitmap at all. + */ + if ((s & (RQ_POSTPONED|RQ_LOCAL_MASK|RQ_NET_MASK)) != RQ_POSTPONED) { if (!(s & RQ_NET_OK) || !(s & RQ_LOCAL_OK)) drbd_set_out_of_sync(mdev, req->i.sector, req->i.size); |