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path: root/drivers/block/drbd/drbd_state.c
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2012-11-30drbd: fixup after wait_even_lock_irq() addition to generic codeJens Axboe
Compiling drbd yields: drivers/block/drbd/drbd_state.c: In function ‘_conn_request_state’: drivers/block/drbd/drbd_state.c:1804:5: error: macro "wait_event_lock_irq" passed 4 arguments, but takes just 3 drivers/block/drbd/drbd_state.c:1801:3: error: ‘wait_event_lock_irq’ undeclared (first use in this function) drivers/block/drbd/drbd_state.c:1801:3: note: each undeclared identifier is reported only once for each function it appears in drivers/block/drbd/drbd_state.c: At top level: drivers/block/drbd/drbd_state.c:1734:1: warning: ‘_conn_rq_cond’ defined but not used [-Wunused-function] Due to drbd having copied the MD definition for wait_event_lock_irq() as well. Kill them. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-11-09drbd: Fix comparison of is_valid_transition()'s return codePhilipp Reisner
is_valid_transition() might return SS_NOTHING_TO_DO. The condition function _req_st_cond() returned SS_NOTHING_TO_DO, which caused the wait_event to abort too early. Therefore drbd_req_state() did not consume the next CL_ST_CHG_SUCCESS or SS_CW_FAILED_BY_PEER causing serve disruption of the state machine logic... Detaching from a single volue was one way to trigger this bug. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-09drbd: Call drbd_md_sync() explicitly after a state change on the connectionPhilipp Reisner
Without this, the meta-data gets updates after 5 seconds by the md_sync_timer. Better to do it immeditaly after a state change. If the asender detects a network failure, it may take a bit until the worker processes the according after-conn-state-change work item. The worker might be blocked in sending something, i.e. it takes until it gets into its timeout. That is 6 seconds by default which is longer than the 5 seconds of the md_sync_timer. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-09drbd: Imporve the error reporting of failed conn state changesPhilipp Reisner
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-09drbd: Fix the way the STATE_SENT bit is clearedPhilipp Reisner
With merging the commit 'drbd: Delay/reject other state changes while establishing a connection' the condition check for clearing the flag was wrong. Move the bit clearing to the __drbd_set_state() function in order to have it already cleared for the other parts of the function. I.e. clearing the susp_fen in the after_state_ch() function. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-09drbd: Do not check aspects that are not subject to change in ↵Philipp Reisner
_conn_requests_state() When _conn_requests_state() is used to change other parts of the state than the connection, do not check for a valid connection transition. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-09drbd: Improve readability of IO resuming after freeze due to no data accessPhilipp Reisner
The previous way of doing the state change was also okay since the state change on the susp flag gets propagated from the mdev to the tconn. Fortunately all this goes away in drbd-9.0 Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-09drbd: Fix IO resuming after connection was established while executing the ↵Philipp Reisner
fence handler Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-09drbd: mutex_unlock "... must no be used in interrupt context"Lars Ellenberg
Documentation of mutex_unlock says we must not use it in interrupt context. So do not call it while holding the spin_lock_irq, but give up the spinlock temporarily. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-09drbd: Fix a race condition that can lead to a BUG()Philipp Reisner
If the preconditions for a state change change after the wait_event() we might hit the BUG() statement in conn_set_state(). With holding the spin_lock while evaluating the condition AND until the actual state change we ensure the the preconditions can not change anymore. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-09drbd: Avoid NetworkFailure state during disconnectPhilipp Reisner
Disconnecting is a cluster wide state change. In case the peer node agrees to the state transition, it sends back the fact on the meta-data connection and closes both sockets. In case the node node that initiated the state transfer sees the closing action on the data-socket, before the P_STATE_CHG_REPLY packet, it was going into one of the network failure states. At least with the fencing option set to something else thatn "dont-care", the unclean shutdown of the connection causes a short IO freeze or a fence operation. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-09drbd: Finish requests that completed while IO was frozenPhilipp Reisner
Requests of an acked epoch are stored on the barrier_acked_requests list. In case the private bio of such a request completes while IO on the drbd device is suspended [req_mod(completed_ok)] then the request stays there. When thawing IO because the fence_peer handler returned, then we use tl_clear() to apply the connection_lost_while_pending event to all requests on the transfer-log and the barrier_acked_requests list. Up to now the connection_lost_while_pending event was not applied on requests on the barrier_acked_requests list. Fixed that. I.e. now the connection_lost_while_pending and resend events are applied to requests on the barrier_acked_requests list. For that it is necessary that the resend event finishes (local only) READS correctly. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-09drbd: introduce stop-sector to online verifyLars Ellenberg
We now can schedule only a specific range of sectors for online verify, or interrupt a running verify without interrupting the connection. Had to bump the protocol version differently, we are now 101. Added verify_can_do_stop_sector() { protocol >= 97 && protocol != 100; } Also, the return value convention for worker callbacks has changed, we returned "true/false" for "keep the connection up" in 8.3, we return 0 for success and <= for failure in 8.4. Affected: receive_state() Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: call local-io-error handler earlyLars Ellenberg
In case we want to hard-reset from the local-io-error handler, we need to call it before notifying the peer or aborting local IO. Otherwise the peer will advance its data generation UUIDs even if secondary. This way, local io error looks like a "regular" node crash, which reduces the number of different failure cases. This may be useful in a bigger picture where crashed or otherwise "misbehaving" nodes are automatically re-deployed. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: do not reset rs_pending_cnt too earlyLars Ellenberg
Fix asserts like block drbd0: in got_BlockAck:4634: rs_pending_cnt = -35 < 0 ! We reset the resync lru cache and related information (rs_pending_cnt), once we successfully finished a resync or online verify, or if the replication connection is lost. We also need to reset it if a resync or online verify is aborted because a lower level disk failed. In that case the replication link is still established, and we may still have packets queued in the network buffers which want to touch rs_pending_cnt. We do not have any synchronization mechanism to know for sure when all such pending resync related packets have been drained. To avoid this counter to go negative (and violate the ASSERT that it will always be >= 0), just do not reset it when we lose a disk. It is good enough to make sure it is re-initialized before the next resync can start: reset it when we re-attach a disk. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: differentiate between normal and forced detachLars Ellenberg
Aborting local requests (not waiting for completion from the lower level disk) is dangerous: if the master bio has been completed to upper layers, data pages may be re-used for other things already. If local IO is still pending and later completes, this may cause crashes or corrupt unrelated data. Only abort local IO if explicitly requested. Intended use case is a lower level device that turned into a tarpit, not completing io requests, not even doing error completion. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: move the drbd_work_queue from drbd_socket to drbd_connectionLars Ellenberg
cherry-picked and adapted from drbd 9 devel branch In 8.4, we don't distinguish between "resource work" and "connection work" yet, we have one worker for both, as we still have only one connection. We only ever used the "data.work", no need to keep the "meta.work" around. Move tconn->data.work to tconn->sender_work. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: allow bitmap to change during writeout from resync_finishedLars Ellenberg
Symptom: messages similar to "FIXME asender in bm_change_bits_to, bitmap locked for 'write from resync_finished' by worker" If a resync or verify is finished (or aborted), a full bitmap writeout is triggered. If we have ongoing local IO, the bitmap may still change during that writeout, pending and not yet processed acks may cause bits to be cleared, while new writes may cause bits to be to be set. To fix this, introduce the drbd_bm_write_copy_pages() variant. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: fix resend/resubmit of frozen IOLars Ellenberg
DRBD can freeze IO, due to fencing policy (fencing resource-and-stonith), or because we lost access to data (on-no-data-accessible suspend-io). Resuming from there (re-connect, or re-attach, or explicit admin intervention) should "just work". Unfortunately, if the re-attach/re-connect did not happen within the timeout, since the commit drbd: Implemented real timeout checking for request processing time if so configured, the request_timer_fn() would timeout and detach/disconnect virtually immediately. This change tracks the most recent attach and connect, and does not timeout within <configured timeout interval> after attach/connect. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Delay/reject other state changes while establishing a connectionPhilipp Reisner
Changes to the role and disk state should be delayed or rejected while we establish a connection. This is necessary, since the peer will base its resync decision on the UUIDs and the state we sent in the drbd_connect() function. The most prominent example for this race is becoming primary after sending state and UUIDs and before the state changes to C_WF_CONNECTION. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Fixed detachLars Ellenberg
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Consider the disk-timeout also for meta-data IO operationsPhilipp Reisner
If the backing device is already frozen during attach, we failed to recognize that. The current disk-timeout code works on top of the drbd_request objects. During attach we do not allow IO and therefore never generate a drbd_request object but block before that in drbd_make_request(). This patch adds the timeout to all drbd_md_sync_page_io(). Before this patch we used to go from D_ATTACHING directly to D_DISKLESS if IO failed during attach. We can no longer do this since we have to stay in D_FAILED until all IO ops issued to the backing device returned. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Reinstate disabling AL updates with invalidate-remotePhilipp Reisner
Commit d0ef827e (drbd: switch configuration interface from connector to genetlink) introduced a regression by removing the ability to set all bits in the out of sync bitmap and to suspend updates to the activity log of a disconnected device via the invalidate-remote management call. Credits for reporting the issue are going to Arne Redlich. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Fixed compat issue with disconnecting 8.4 from a primary 8.3Philipp Reisner
For compatibility reasons 8.4 has to send P_STATE_CHG_REQ (instead of P_CONN_ST_CHG_REQ) when disconnecting. In the receiving code path we missed to convert the old answer (P_STATE_CHG_REPLY) back to 8.4 logic. Therefore the CL_ST_CHG_SUCCESS or CL_ST_CHG_FAIL bit in the flags word of mdev got set, while the state code was waiting for the CONN_WD_ST_CHG_OKAY or CONN_WD_ST_CHG_FAIL bits in tconn. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Log failures of connection state changesPhilipp Reisner
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Do not send state packets while lower than C_CONNECTED cstatePhilipp Reisner
I.e. in C_WF_REPORT_PARAMS or in C_WF_CONNECTION. Sending may already work in these cstates, but the peer still expects the HandShake / ConnectionFeatures packet. Actually triggered by the Testuite on kugel. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Fixes from the drbd-8.3 branchPhilipp Reisner
* drbd-8.3: drbd: O_SYNC gives EIO on ramdisks for some kernels (eg. RHEL6). drbd: send intermediate state change results to the peer Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Fixes from the drbd-8.3 branchPhilipp Reisner
* drbd-8.3: drbd: fix spurious meta data IO "error" drbd: Fixed a race condition between detach and start of resync drbd: fix harmless race to not trigger an ASSERT drbd: Derive sync-UUIDs only from the bitmap-uuid if it is non-zero drbd: Fixed current UUID generation (regression introduced recently, after 8.3.11) Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Silenced compiler warningsPhilipp Reisner
Since version 4.6.1 gcc warns about variables that get a value assigned, but which are never read later on. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Do not display bogus log lines for pdsk in case pdsk < D_UNKNOWNPhilipp Reisner
This was a regression recently introduced with commit 7848ddb752c09b6dfd1ddfabb06b69b08aa8f6b9 "drbd: Correctly handle resources without volumes" Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Bugfix for the connection behaviorPhilipp Reisner
If we get into the C_BROKEN_PIPE cstate once, the state engine set the thi->t_state of the receiver thread to restarting. But with the while loop in drbdd_init() a new connection gets established. After the call into drbdd() returns immediately since the thi->t_state is not RUNNING. The restart of drbd_init() then resets thi->t_state to RUNNING. I.e. after entering C_BROKEN_PIPE once, the next successful established connection gets wasted. The two parts of the fix: * Do not cause the thread to restart if we detect the issue with the sockets while we are in C_WF_CONNECTION. * Make sure that all actions that would have set us to C_BROKEN_PIPE happen before the state change to C_WF_REPORT_PARAMS. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Turn tl_apply() into tl_abort_disk_io()Andreas Gruenbacher
There is no need to overly generalize this function; it only makes the code harder to understand. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Consider that the no-data-condition could be in connected statePhilipp Reisner
...when the peer has inconsistent data. In that case we failed to clear the susp_nod flag. When the local disk was attached again Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Dropped wrong clause to generate new current UUIDsPhilipp Reisner
Looks like a remainder from long ago. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Correctly handle resources without volumesPhilipp Reisner
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Eliminated the "notified peer" messagesPhilipp Reisner
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Fixed removal of volumes/devices from connected resourcesPhilipp Reisner
When removing a volume/device we need to switch the connection status of the peer back into WFReportParams. Before this fix it was left in Connected state. That means that the peer device continued to inform us about state changes, etc... But we deleted that minor -> protocol error. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: on attach, enforce clean meta dataLars Ellenberg
Detection of unclean shutdown has moved into user space. The kernel code will, whenever it updates the meta data, mark it as "unclean", and will refuse to attach to such unclean meta data. "drbdadm up" now schedules "drbdmeta apply-al", which will apply the activity log to the bitmap, and/or reinitialize it, if necessary, as well as set a "clean" indicator flag. This moves a bit code out of kernel space. As a side effect, it also prevents some 8.3 module from accidentally ignoring the 8.4 style activity log, if someone should downgrade, whether on purpose, or accidentally because he changed kernel versions without providing an 8.4 for the new kernel, and the new kernel comes with in-tree 8.3. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: detach from frozen backing devicePhilipp Reisner
* drbd-8.3: documentation: Documented detach's --force and disk's --disk-timeout drbd: Implemented the disk-timeout option drbd: Force flag for the detach operation drbd: Allow new IOs while the local disk in in FAILED state drbd: Bitmap IO functions can not return prematurely if the disk breaks drbd: Added a kref to bm_aio_ctx drbd: Hold a reference to ldev while doing meta-data IO drbd: Keep a reference to the bio until the completion handler finished drbd: Implemented wait_until_done_or_disk_failure() drbd: Replaced md_io_mutex by an atomic: md_io_in_use drbd: moved md_io into mdev drbd: Immediately allow completion of IOs, that wait for IO completions on a failed disk drbd: Keep a reference to barrier acked requests Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Fixed state transitions in case reading meta data failesPhilipp Reisner
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Fixes from the 8.3 development branchPhilipp Reisner
* commit 'ae57a0a': drbd: Only print sanitize state's warnings, if the state change happens drbd: we should write meta data updates with FLUSH FUA drbd: fix limit define, we support 1 PiByte now drbd: fix log message argument order drbd: Typo in user-visible message. drbd: Make "(rcv|snd)buf-size" and "ping-timeout" available for the proxy, too. drbd: Allow keywords to be used in multiple config sections. drbd: fix typos in comments. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: downgraded error printk to infoLars Ellenberg
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Convert the generic netlink interface to accept connection endpointsAndreas Gruenbacher
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: RCU for disk_confPhilipp Reisner
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Renamed the net_conf_update mutex to conf_updatePhilipp Reisner
Preparing to use the same mutex for disk_conf updates Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: fix thread stop deadlockLars Ellenberg
There are races where the receiver may be exiting, but still need the worker to process some stuff. Do not wait for the receiver to die from an exiting worker. The receiver must already be dead in case the worker decides to exit. If the receiver was still alive, it may still want to queue work, and do drbd_flush_workqueue() from it's disconnect cleanup code, which would no longer be processed by an exiting worker. This also would deadlock, if the worker was to synchornously wait for the receiver to die. Do not implicitly stop the worker. The worker will only be stopped from configuration context, from conn_reconfig_done(), drbd_adm_down() or drbd_adm_delete_connection(), after making sure the receiver is already stopped. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: fix race when forcefully disconnectingLars Ellenberg
If a forced disconnect hits a restarting receiver right after it passed its final "if (C_DISCONNECTING)" test in drbdd_init(), but before it was actually restarted by drbd_thread_setup, we could be left with a connection stuck in C_DISCONNECTING, never reaching C_STANDALONE, which would be necessary to take it down or reconfigure it. Move the last cleanup into w_after_conn_state_ch(), and do an additional state change request in conn_try_disconnect(), just in case. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: fix various disconnecting racesLars Ellenberg
If an admin requests disconnect at a time when the state handling already disconnects/reconnects, there have been some races. Make sure to always really stop the network threads before returning success for disconnect. Do not pretend successfull forced disconnect, if the state handling returned an error. Return success from drbd_adm_down() only after all threads are finished. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Removed the OBJECT_DYING and the CONFIG_PENDING bitsPhilipp Reisner
superseded by refcounting Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-11-08drbd: Basic refcounting for drbd_tconnPhilipp Reisner
References hold by: * Each (running) drbd thread has a reference on tconn * Each mdev has a referenc on tconn * Beeing in the all_tconn list counts for one reference * Each after_conn_state_chg_work has a reference to tconn Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>