diff options
| author | Philipp Reisner | 2011-04-14 01:24:47 +0200 |
|---|---|---|
| committer | Philipp Reisner | 2012-11-08 16:45:18 +0100 |
| commit | 303d1448a048fb5b099babc5f41d0b1e22238778 (patch) | |
| tree | dccb81765e81d3275addf91ff9644bacdda64b60 /drivers/block/drbd/drbd_req.c | |
| parent | drbd: protect all idr accesses that might sleep with drbd_cfg_rwsem (diff) | |
| download | kernel-qcow2-linux-303d1448a048fb5b099babc5f41d0b1e22238778.tar.gz kernel-qcow2-linux-303d1448a048fb5b099babc5f41d0b1e22238778.tar.xz kernel-qcow2-linux-303d1448a048fb5b099babc5f41d0b1e22238778.zip | |
drbd: Runtime changeable wire protocol
The wire protocol is no longer a property that is negotiated
between the two peers. It is now expressed with two bits
(DP_SEND_WRITE_ACK and DP_SEND_RECEIVE_ACK) in each data
packet. Therefore the primary node is free to change the
wire protocol at any time without disconnect/reconnect.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Diffstat (limited to 'drivers/block/drbd/drbd_req.c')
| -rw-r--r-- | drivers/block/drbd/drbd_req.c | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index fd0b4529a4b9..0f1a29fc7228 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c @@ -323,7 +323,7 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what, struct bio_and_error *m) { struct drbd_conf *mdev = req->w.mdev; - int rv = 0; + int p, rv = 0; if (m) m->bio = NULL; @@ -344,6 +344,10 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what, * and from w_read_retry_remote */ D_ASSERT(!(req->rq_state & RQ_NET_MASK)); req->rq_state |= RQ_NET_PENDING; + p = mdev->tconn->net_conf->wire_protocol; + req->rq_state |= + p == DRBD_PROT_C ? RQ_EXP_WRITE_ACK : + p == DRBD_PROT_B ? RQ_EXP_RECEIVE_ACK : 0; inc_ap_pending(mdev); break; @@ -500,7 +504,7 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what, atomic_add(req->i.size >> 9, &mdev->ap_in_flight); if (bio_data_dir(req->master_bio) == WRITE && - mdev->tconn->net_conf->wire_protocol == DRBD_PROT_A) { + !(req->rq_state & (RQ_EXP_RECEIVE_ACK | RQ_EXP_WRITE_ACK))) { /* this is what is dangerous about protocol A: * pretend it was successfully written on the peer. */ if (req->rq_state & RQ_NET_PENDING) { @@ -550,6 +554,7 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what, req->rq_state |= RQ_NET_DONE; /* fall through */ case WRITE_ACKED_BY_PEER: + D_ASSERT(req->rq_state & RQ_EXP_WRITE_ACK); /* protocol C; successfully written on peer. * Nothing to do here. * We want to keep the tl in place for all protocols, to cater @@ -560,11 +565,14 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what, * request could set NET_DONE right here, and not wait for the * P_BARRIER_ACK, but that is an unnecessary optimization. */ + goto ack_common; /* this makes it effectively the same as for: */ case RECV_ACKED_BY_PEER: + D_ASSERT(req->rq_state & RQ_EXP_RECEIVE_ACK); /* protocol B; pretends to be successfully written on peer. * see also notes above in HANDED_OVER_TO_NETWORK about * protocol != C */ + ack_common: req->rq_state |= RQ_NET_OK; D_ASSERT(req->rq_state & RQ_NET_PENDING); dec_ap_pending(mdev); @@ -574,8 +582,8 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what, break; case POSTPONE_WRITE: - /* - * If this node has already detected the write conflict, the + D_ASSERT(req->rq_state & RQ_EXP_WRITE_ACK); + /* If this node has already detected the write conflict, the * worker will be waiting on misc_wait. Wake it up once this * request has completed locally. */ @@ -646,7 +654,7 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what, } if ((req->rq_state & RQ_NET_MASK) != 0) { req->rq_state |= RQ_NET_DONE; - if (mdev->tconn->net_conf->wire_protocol == DRBD_PROT_A) + if (!(req->rq_state & (RQ_EXP_RECEIVE_ACK | RQ_EXP_WRITE_ACK))) atomic_sub(req->i.size>>9, &mdev->ap_in_flight); } _req_may_be_done(req, m); /* Allowed while state.susp */ |