drbd: Finished the "on-no-data-accessible suspend-io;" functionality

When no data is accessible (no connection to the peer, nor a local disk)
allow the user to select to freeze all IO operations instead of getting
IO errors.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
index 48647589aa0d..8259d4f77285 100644
--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -226,6 +226,8 @@ void _req_may_be_done(struct drbd_request *req, struct bio_and_error *m)
                 return;
         if (s & RQ_LOCAL_PENDING)
                 return;
+        if (mdev->state.susp)
+                return;
 
         if (req->master_bio) {
                 /* this is data_received (remote read)
@@ -634,6 +636,28 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what,
                 /* else: done by handed_over_to_network */
                 break;
 
+        case fail_frozen_disk_io:
+                if (!(req->rq_state & RQ_LOCAL_COMPLETED))
+                        break;
+
+                _req_may_be_done(req, m);
+                break;
+
+        case restart_frozen_disk_io:
+                if (!(req->rq_state & RQ_LOCAL_COMPLETED))
+                        break;
+
+                req->rq_state &= ~RQ_LOCAL_COMPLETED;
+
+                rv = MR_READ;
+                if (bio_data_dir(req->master_bio) == WRITE)
+                        rv = MR_WRITE;
+
+                get_ldev(mdev);
+                req->w.cb = w_restart_disk_io;
+                drbd_queue_work(&mdev->data.work, &req->w);
+                break;
+
         case resend:
                 /* If RQ_NET_OK is already set, we got a P_WRITE_ACK or P_RECV_ACK
                    before the connection loss; only P_BARRIER_ACK was missing.