drbd_device_work is a work item that has a reference to a device,
while drbd_work is a more generic work item that does not carry
a reference to a device.
All callbacks get a pointer to a drbd_work instance, those callbacks
that expect a drbd_device_work use the container_of macro to get it.
Signed-off-by: Andreas Gruenbacher <agruen@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
The implicit dependency on a variable inside the macro is problematic.
Signed-off-by: Andreas Gruenbacher <agruen@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
DRBD was using dev_err() and similar all over the code; instead of having to
write dev_err(disk_to_dev(device->vdisk), ...) to convert a drbd_device into a
kernel device, a DEV macro was used which implicitly references the device
variable. This is terrible; introduce separate drbd_err() and similar macros
with an explicit device parameter instead.
Signed-off-by: Andreas Gruenbacher <agruen@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
In a setup where a device (aka volume) can replicate to multiple peers and one
connection can be shared between multiple devices, we need separate objects to
represent devices on peer nodes and network connections.
As a first step to introduce multiple connections per device, give each
drbd_device object a single drbd_peer_device object which connects it to a
drbd_connection object.
Signed-off-by: Andreas Gruenbacher <agruen@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
sed -i -e 's:all_tconn:connections:g' -e 's:tconn:connection:g'
Signed-off-by: Andreas Gruenbacher <agruen@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Mark functions drbd_request_prepare() and find_oldest_request() as
static in drbd/drbd_req.c because they are not used outside this file.
This eliminates the following warnings in drbd/drbd_req.c:
drivers/block/drbd/drbd_req.c:1037:1: warning: no previous prototype for ‘drbd_request_prepare’ [-Wmissing-prototypes]
drivers/block/drbd/drbd_req.c:1323:22: warning: no previous prototype for ‘find_oldest_request’ [-Wmissing-prototypes]
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
For a long time, the receiving side has spread "too large" incoming
requests over multiple bios. No need to shrink our max_bio_size
(max_hw_sectors) if the peer is reconfigured to use a different storage.
The problem manifests itself if we are not the top of the device stack
(DRBD is used a LVM PV).
A hardware reconfiguration on the peer may cause the supported
max_bio_size to shrink, and the connection handshake would now
unnecessarily shrink the max_bio_size on the active node.
There is no way to notify upper layers that they have to "re-stack"
their limits. So they won't notice at all, and may keep submitting bios
that are suddenly considered "too large for device".
We already check for compatibility and ignore changes on the peer,
the code only was masked out unless we have a fully established connection.
We just need to allow it a bit earlier during the handshake.
Also consider max_hw_sectors in our merge bvec function, just in case.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The sanity check when receiving P_BARRIER_ACK does expect all write
requests with a given req->epoch to have been either all replicated,
or all not replicated.
Because req->epoch was assigned before calling maybe_pull_ahead(),
this expectation was not met, leading to an off-by-one in the sanity
check, and further to a "Protocol Error".
Fix: move the call to maybe_pull_ahead() a few lines up,
and assign req->epoch only after that.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We completed empty flushes (blkdev_issue_flush()) with IO error
if we lost the local disk, even if we still have an established
replication link to a healthy remote disk.
Fix this to only report errors to upper layers,
if neither local nor remote data is reachable.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There may have been more incoming requests while we where preparing
the current transaction. Try to consolidate more updates into this
transaction until we make no more progres.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The IO accounting of the drbd "queue depth" was misleading.
We only started IO accounting once we already wrote the activity log.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Depending on current IO depth, try to consolidate as many updates
as possible into one activity log transaction.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is in preparation to be able to defer requests that need to wait
for an activity log transaction to a submitter workqueue.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When we notice a disk failure on the receiving side,
we stop sending it new incoming writes.
Depending on exact timing of various events, the same transfer log epoch
could end up containing both replicated (before we noticed the failure)
and local-only requests (after we noticed the failure).
The sanity checks in tl_release(), called when receiving a
P_BARRIER_ACK, check that the ack'ed transfer log epoch matches
the expected epoch, and the number of contained writes matches
the number of ack'ed writes.
In this case, they counted both replicated and local-only writes,
but the peer only acknowledges those it has seen. We get a mismatch,
resulting in a protocol error and disconnect/reconnect cycle.
Messages logged are
"BAD! BarrierAck #%u received with n_writes=%u, expected n_writes=%u!\n"
A similar issue can also be triggered when starting a resync while
having a healthy replication link, by invalidating one side, forcing a
full sync, or attaching to a diskless node.
Fix this by closing the current epoch if the state changes in a way
that would cause the replication intent of the next write.
Epochs now contain either only non-replicated,
or only replicated writes.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
If we detach due to local read-error (which sets a bit in the bitmap),
stay Primary, and then re-attach (which re-reads the bitmap from disk),
we potentially lost the "out-of-sync" (or, "bad block") information in
the bitmap.
Always (try to) write out the changed bitmap pages before going diskless.
That way, we don't lose the bit for the bad block,
the next resync will fetch it from the peer, and rewrite
it locally, which may result in block reallocation in some
lower layer (or the hardware), and thereby "heal" the bad blocks.
If the bitmap writeout errors out as well, we will (again: try to)
mark the "we need a full sync" bit in our super block,
if it was a READ error; writes are covered by the activity log already.
If that superblock does not make it to disk either, we are sorry.
Maybe we just lost an entire disk or controller (or iSCSI connection),
and there actually are no bad blocks at all, so we don't need to
re-fetch from the peer, there is no "auto-healing" necessary.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>