Fix warnings of the following nature in the drbd header:
In file included from drivers/block/drbd/drbd_bitmap.c:32:
drivers/block/drbd/drbd_int.h: In function 'drbd_get_syncer_progress':
drivers/block/drbd/drbd_int.h:2234: warning: comparison is always false due to limited range of data
where mdev->rs_total (an unsigned long) is being compared to 1ULL << 32, which
is always false on a 32-bit machine.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
drbdadm already has a --dry-run option, so this option cannot directly be
passed through to drbdsetup. Rename the drbdsetup option to resolve this
conflict.
For backward compatibility, make --dry-run an alias of --tentative.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This is equivalent to how the attach and connect commands work.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Duplicate this file in the kernel module and in user space; both sides need it.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This is done by introducing drbd_nla_find_nested() which handles the flag
before calling nla_find_nested().
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
It is not "to small", but "too small".
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
For large resync rates, seq_printf_with_thousands_grouping()
accidentally only produced Y,000,00Y, instead of the real numbers.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Before mainline commit ea5693cc (v2.6.29-rc1), empty nested netlink attributes
were not allowed. Fix that by leaving out nested attributes if they are empty
and by allowing the top-level attributes to be missing.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Since we need to hold that mutex anyways to make sure the peer
gets that change in the right position in the data stream,
it makes a lot of sense to use the same mutex to ensure existence
of the tfm.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
* the peer does not speak protocol_version 100 and the
user wants to change one of:
- wire_protocol
- two_primaries
- integrity_alg
* the user wants to remove the allow_two_primaries flag
when there are two primaries
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
The 32-bit resync_after netlink field takes a device minor number as
parameter, which is no longer limited to 255. We cannot statically
verify which device numbers are valid, so set the ummer limit to the
highest possible signed 32-bit integer.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Activity log transaction writes are serialized on a bit lock.
If several CPUs race to write an AL transaction,
those that did not get the lock the first time
may continue as soon as there are no more pending transactions.
The do not need to all grab the lock in turn,
just to realize that the AL is clean already,
and they have nothing to do.
This also closes a potential deadlock with drbd_adm_disk_opts.
Once it got the AL bit lock, it knows there are no pending transactions,
the AL is clean, and it should be safe to wait for all element references
to drop to zero.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This is what it is called in config files and on the command line as
well.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Instead of returning a ret_code outside of the range of enum
drbd_ret_code, use NO_ERROR to indicate success. This way,
ret_code has the same meaning in all packets.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
* Updates to all configuration items is done under genl_lock().
Including removal of mdevs or tconns.
* All read non sleeping read sides are protected by rcu
* All sleeping read sides keep reference counts to keep the
objects alive
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Preparing removal of drbd_cfg_rwsem
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Preparing removal of drbd_cfg_rwsem
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Change the --no-tcp-cork drbdsetup command line option as well as
the no_cork netlink packet.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Change the --no-md-flushes drbdsetup command line option as well as
the no_md_flush netlink packet.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Change the --no-disk-drain drbdsetup command line option as well as
the no_disk_drain netlink packet.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Change the --no-disk-flushes drbdsetup command line option as well as
the no_disk_flush netlink packet.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This removes the issue with using peer_seq_lock out of different
contexts.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
* Moved rs_planed into it, named total
* When having a pointer to the object the values can
be embedded into the fifo object.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
...and drop explicit typecasts (int)meta_dev_idx < 0.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>
An administrative detach used to request a state change directly to D_DISKLESS,
first suspending IO to avoid the last put_ldev() occuring from an endio handler,
potentially in irq context.
This is not enough on the receiving side (typically secondary), we may miss
some peer_req on the way to local disk, which then may do the last put_ldev()
from their drbd_peer_request_endio().
This patch makes the detach always go through the intermediate D_FAILED state.
We may consider to rename it D_DETACHING.
Alternative approach would be to create yet an other work item to be scheduled
on the worker, do the destructor work from there, and get the timing right.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>
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>
The main purpose of this is to allow to turn data integrity checking on
and off on demand without causing interruptions.
Implemented by allocating tconn->peer_integrity_tfm only when receiving
a P_PROTOCOL message. l accesses to tconn->peer_integrity_tf happen in
worker context, and no further synchronization is necessary.
On the sender side, tconn->integrity_tfm is modified under
tconn->data.mutex, and a P_PROTOCOL message is sent whenever. All
accesses to tconn->integrity_tfm already happen under this mutex.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
We allocate hash transformations with crypto_alloc_hash() which will
only return hash algorithms. It is not necessary to reconfirm that we
actually got a hash algorithm.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
It is not enough to grab net_conf->integrity_alg under rcu_read_lock()
and access it outside of it; the entire net_conf object may be gone by
then.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
sc was short for syncer conf, which does not exist anymore anyways.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
The DRBD_GENL_F_SET_DEFAULTS flag was ignored
for drbd_adm_disk_opts() and drbd_adm_net_opts().
Factor out drbd_set_*_defaults() helper functions,
and call them appropriately.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
So for this was simply not considered after the options have been
re-arranged.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>
Calling kobject_uevent, which may sleep, from within rcu_read_lock()
protected regions is not possible.
This particular kobject_uevent also is also wrong. It was supposed to
trigger a udev run, just in case something relevant to udev symlink
magic has changed, when adjusting runtime re-configurable settings while
we still had the "syncer conf". It was improperly placed in connect
when we dropped the "syncer conf". The right thing to do is probably to
call "udevadm trigger" directly in those cases where drbdadm thinks
there was a need to trigger extra udev runs.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>
When the last volume of a replication group is unconfigured,
the worker thread exits. To not interfere with cleanup
of other threads, before the the last cleanups run,
we need to make sure the receiver has already exited.
The commend explaining that clearly belongs above
drbd_thread_stop(&tconn->receiver), not in the cleanup loop below.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
We use our own copy of kernel_setsockopt, and did not mess around with
get_fs/set_fs, since we thought we knew we would always be KERNEL_DS
anyways. Apparently not so for at least user mode linux, so put the
set_fs(KERNEL_DS) in there.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
We had drbd_adm_get_status (one single volume),
and drbd_adm_get_status_all (dump of all volumes of all resources).
This enhances the latter to be able to dump all volumes
of just one specific resource.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Now since it is possible to change the two_primaries config
flag while the connection is up, make sure we treat a peer_req
in a consistent way if the config flag changes while the peer_req
is under IO.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Removing the get_net_conf()/put_net_conf() functions
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Removing the get_net_conf()/put_net_conf() calls
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>
With this commit the locking for all accesses to IDRs is complete:
* Non sleeping read accesses are protected by RCU
* sleeping read accesses are protocted by a read lock on drbd_cfg_rwsem
* accesses that add anything are protected by a write lock
* accesses that remove an object are protoected by a write lock
and a call to synchronize_rcu() after it is removed from the IDR
and before the object is actually free()ed.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Since have now header 100, that has space for 16 bit volume numbers,
the high byte of the length in header 95 is no longer reserved for
8 bit volume numbers.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
The 8 byte header finally becomes too small. With the protocol 100 header we
have 16 bit for the volume number, proper 32 bit for the data length, and
32 bit for further extensions in the future.
Previous versions of drbd are using version 80 headers for all packets
short enough for protocol 80. They support both header versions in
worker context, but only version 80 headers in asynchronous context.
For backwards compatibility, continue to use version 80 headers for
short packets before protocol version 100.
From protocol version 100 on, use the same header version for all
packets.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Prepare the introduction of the protocol 100 headers. The actual protocol
header is removed for the packet declarations. I.e. allow us to use the
packets with different headers.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Centralize sock->mutex locking and unlocking in [drbd|conn]_prepare_command()
and [drbd|conn]_send_comman().
Therefore all *_send_* functions are touched to use these primitives instead
of drbd_get_data_sock()/drbd_put_data_sock() and former helper functions.
That change makes the *_send_* functions more standardized.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Recent commit drbd: get rid of bio_split, allow bios of "arbitrary" size
had a reference count leak: it only deactivated the first of several
activity log extents for intervals crossing extent boundaries.
This commit generalizes on bios spanning multiple activity log extents
in drbd_al_begin_io, and adds the necessary loop around lc_put in
drbd_al_complete_io as well.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Where "arbitrary" size is currently 1 MiB, which is the BIO_MAX_SIZE
for architectures with 4k PAGE_CACHE_SIZE (most).
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
We want to avoid bio_split for bios crossing activity log boundaries.
So we may need to activate two activity log extents "atomically".
drbd_al_begin_io() needs to know more than just the start sector.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
So we can initialize a clean on disk activity log area,
without the module complaining with loud assert messages
because of checksum or magic value mismatches.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Packets of type P_HAND_SHAKE define which protocol versions and features
a node supports. For clarity, call those packets P_CONNECTION_FEATURES
instead.
(This does not determine the features that a specific drbd device
supports, such as drbd protocol A, B, C.)
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
The first packets exchanged when a connection is established are
referred to as P_HAND_SHAKE_S and P_HAND_SHAKE_M in the code, followed
by P_HAND_SHAKE packets. To avoid confusion between these two unrelated
things, call the initial packets P_INITIAL_DATA and P_INITIAL_META.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
During a disconnect the oc variable in _conn_request_state()
could become outdated. Determin the common old state after
sleeping.
While at it, I implemented that for all parts of the state
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
The receive handlers do not all handle unknown volume numbers the same
way.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
These messages can only trigger in case there is a pretty obvious
internal programming error.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
There is no need to send protocol 80 headers to peers that understand
protocol 95 headers. Make sure that we don't send protocol 95 headers
until we have agreed upon a protocol version with our peer, though.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
The pattern of receiving a fixed number of bytes and warning if a short
packet is received and the receiver has not actively been interruped is
repeated many times; clean that up.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This type is not used anywhere else.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This is also checked further below in the same function.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This helps to ensure that we don't miss one of them when changing their
return value semantics.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Q: Can this case even trigger? Is failing this way any better than one
that causes a NULL pointer access?
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
It actually returned the lowest volume number. While doing that
renamed a few wrongly named variables.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This commit breaks the API again.
Move per-volume former syncer options into disk_conf.
Move per-connection former syncer options into net_conf.
Renamed the remainign sync_conf to res_opts
Syncer settings have been changeable at runtime, so we need to prepare
for these settings to be runtime-changeable in their new home as well.
Introduce new configuration operations, and share the netlink attribute
between "attach" (create new disk) and "disk-opts" (change options).
Same for "connect" and "net-opts".
Some fields cannot be changed at runtime, however.
Introduce a new flag GENLA_F_INVARIANT to be able to trigger on that in
the generated validation and assignment functions.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
If drbd_adm_attach failed early, it left the CONFIG_PENDING bit on,
blocking any further conn_reconfig_start on that connection.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
That is necessary in case a connection does not have a volume 0
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
In the context of drbd-8.4 it no longer makes sense to
dissalow that.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Took the chance and converted tconn_process_done_ee() to use
idr_for_each_entry()
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This greatly simplifies deconfiguration of whole resources.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
somehow a "goto abort" was introduced with commit
drbd: Extracted is_valid_transition() out of sanitize_state()
which left drbd_req_state still holding the spin lock.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
We have resources resp. connections, volumes, and minor numbers.
A config request may specifies all three of them.
If it turns out that the minor belongs to a different connection, or a
different volume number in the same connection, that configuration
request is invalid.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Follow O_CREAT semantics when creating connection or minor device/volume
objects. If we need O_CREAT|O_EXCL semantics some time down the road,
we can add NLM_F_EXCL to the netlink message flags.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Even if the connection is still established.
We should be able to reduce a volume from a replication group,
without taking the whole group offline.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Get rid of a temporary variable and, funny bitand assignment.
Just short circuit, returning false, once we encounter the first
still configured volume.
FIXME verify call sites for need of rcu_read_lock or stronger.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
We want to see existing connection objects, even if they do not
currently have volumes attached.
Change the .dumpit variant of drbd_adm_get_status to iterate not over
minor devices, but over connections + volumes.
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>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- struct drbd_conf { ... unsigned long flags; ... }
+ struct drbd_conf { ... unsigned long drbd_flags[N]; ... }
And introduce wrapper functions for test/set/clear bit operations
on this member.
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 intention of force-detach is to be able to deal with a completely
unresponsive lower level IO stack, which does not even deliver error
completions anymore, but no completion at all.
In all other cases, we must still wait for the meta data IO completion.
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 has not yet been observed, but conceivably, when using GFP_KERNEL
allocations from drbd_md_sync(), drbd_flush_after_epoch() or
receive_SyncParam(), we could trigger additional IO to our own device,
or an other device in a criss-cross setup, and end up in a local
deadlock, or potentially a distributed deadlock in a criss-cross setup
involving the peer blocked in a similar way waiting for us to make
progress.
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 former comment arguing that GFP_KERNEL was good enough was wrong: it
did not take resize into account at all, and assumed the only path
leading here was the normal attach on a still secondary device, so no
deadlock would be possible.
Both resize on a Primary, or attach on a diskless Primary,
could potentially deadlock.
drbd_bm_resize() is called while IO to the respective device is
suspended, so we must use GFP_NOIO to avoid potential deadlock.
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>
"aborting" requests, or force-detaching the disk, is intended for
completely blocked/hung local backing devices which do no longer
complete requests at all, not even do error completions. In this
situation, usually a hard-reset and failover is the only way out.
By "aborting", basically faking a local error-completion,
we allow for a more graceful swichover by cleanly migrating services.
Still the affected node has to be rebooted "soon".
By completing these requests, we allow the upper layers to re-use
the associated data pages.
If later the local backing device "recovers", and now DMAs some data
from disk into the original request pages, in the best case it will
just put random data into unused pages; but typically it will corrupt
meanwhile completely unrelated data, causing all sorts of damage.
Which means delayed successful completion,
especially for READ requests,
is a reason to panic().
We assume that a delayed *error* completion is OK,
though we still will complain noisily about it.
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>
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>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The DISCARD_CONCURRENT flag should be set on one node and cleared on the
other node.
As the code was before it was theoretical possible that a node accepts the
meta socket, but has to close it later on, and keeps the DISCARD_CONCURRENT
flag.
Correct this by moving the clear_bit(DISCARD_CONCURRENT) where the packet
gets sent.
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 now can schedule only a specific range of sectors for online verify,
or interrupt a running verify without interrupting the connection.
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 is at least the worker context, the receiver context, the context of
receiving netlink packts and processes reading a sysfs attribute that access
the uuids.
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>
With the old code, when you allocate a bio from a bio pool you have to
implement your own destructor that knows how to find the bio pool the
bio was originally allocated from.
This adds a new field to struct bio (bi_pool) and changes
bio_alloc_bioset() to use it. This makes various bio destructors
unnecessary, so they're then deleted.
v6: Explain the temporary if statement in bio_put
Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: NeilBrown <neilb@suse.de>
CC: Alasdair Kergon <agk@redhat.com>
CC: Nicholas Bellinger <nab@linux-iscsi.org>
CC: Lars Ellenberg <lars.ellenberg@linbit.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull block-related fixes from Jens Axboe:
- Improvements to the buffered and direct write IO plugging from
Fengguang.
- Abstract out the mapping of a bio in a request, and use that to
provide a blk_bio_map_sg() helper. Useful for mapping just a bio
instead of a full request.
- Regression fix from Hugh, fixing up a patch that went into the
previous release cycle (and marked stable, too) attempting to prevent
a loop in __getblk_slow().
- Updates to discard requests, fixing up the sizing and how we align
them. Also a change to disallow merging of discard requests, since
that doesn't really work properly yet.
- A few drbd fixes.
- Documentation updates.
* 'for-linus' of git://git.kernel.dk/linux-block:
block: replace __getblk_slow misfix by grow_dev_page fix
drbd: Write all pages of the bitmap after an online resize
drbd: Finish requests that completed while IO was frozen
drbd: fix drbd wire compatibility for empty flushes
Documentation: update tunable options in block/cfq-iosched.txt
Documentation: update tunable options in block/cfq-iosched.txt
Documentation: update missing index files in block/00-INDEX
block: move down direct IO plugging
block: remove plugging at buffered write time
block: disable discard request merge temporarily
bio: Fix potential memory leak in bio_find_or_create_slab()
block: Don't use static to define "void *p" in show_partition_start()
block: Add blk_bio_map_sg() helper
block: Introduce __blk_segment_map_sg() helper
fs/block-dev.c:fix performance regression in O_DIRECT writes to md block devices
block: split discard into aligned requests
block: reorganize rounding of max_discard_sectors
We need to write the whole bitmap after we moved the meta data
due to an online resize operation.
With the support for one peta byte devices bitmap IO was optimized
to only write out touched pages. This optimization must be turned
off when writing the bitmap after an online resize.
This issue was introduced with drbd-8.3.10.
The impact of this bug is that after an online resize, the next
resync could become larger than expected.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>
DRBD has a concept of request epochs or reorder-domains,
which are separated on the wire by P_BARRIER packets.
Older DRBD is not able to handle zero-sized requests at all,
so we need to map empty flushes to these drbd barriers.
These are the equivalent of empty flushes, and
by default trigger flushes on the receiving side anyways
(unless not supported or explicitly disabled),
so there is no need to handle this differently in newer drbd either.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
The pdflush thread is long gone, so this patch removes references to pdflush
from drbd comments.
Cc: drbd-dev@lists.linbit.com
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Unconditionally announce FLUSH/FUA to upper layers.
If the lower layers on either node do not actually support this,
generic_make_request() will deal with it.
If this causes performance regressions on your setup,
make sure there are no volatile caches involved,
and mount -o nobarrier or equivalent.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
We capped our max_bio_size respectively max_hw_sectors with
min_t(int, lower level limit, our limit);
unfortunately, some drivers, e.g. the kvm virtio block driver, initialize their
limits to "-1U", and that is of course a smaller "int" value than our limit.
Impact: we started to request 16 MB resync requests,
which lead to protocol error and a reconnect loop.
Fix all relevant constants and parameters to be unsigned int.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
If you do back to back wait-sync/invalidate on a Primary in a tight loop,
during application IO load, you could trigger a race:
kernel: block drbd6: FIXME going to queue 'set_n_write from StartingSync'
but 'write from resync_finished' still pending?
Fix this by changing the order of the drbd_queue_work() and
the wake_up() in dec_ap_pending(), and adding the additional
drbd_flush_workqueue() before requesting the full sync.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Occasionally, if we disconnect, we triggered this assert:
block drbd7: ASSERT FAILED tl_hash[27] == c30b0f04, expected NULL
hlist_del() happens only on master bio completion.
We used to wait for pending IO to complete before freeing tl_hash
on disconnect. We no longer do so, since we learned to "freeze"
IO on disconnect.
If the local disk is too slow, we may reach C_STANDALONE early,
and there are still some requests pending locally when we call
drbd_free_tl_hash().
If we now free the tl_hash, and later the local IO completion completes
the master bio, which then does hlist_del() and clobbers freed memory.
Do hlist_del_init() and hlist_add_fake() before kfree(tl_hash),
so the hlist_del() on master bio completion is harmless.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>
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>
We cache the congestion status in mdev->congestion_reason whenever
drbd_congested() was called.
Reset this cached info before reporting it when reading /proc/drbd.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
If the drbd worker thread is synchronously waiting for some userland
callback, we don't want some casual pageout to block on us.
Have drbd_congested() report congestion in that case.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>
We must not look at mdev->actlog, unless we have a get_ldev() reference.
It also does not make much sense to try to disconnect or pull-ahead of
the peer, if we don't have good local data.
Only even consider congestion policies, if our local disk is D_UP_TO_DATE.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
If a read is aborted due to force-detach of a supposedly unresponsive
local backing device, and retried on the peer, it can happen that the
local request later still completes (hopefully with an error).
As it may already have been completed to upper layers meanwhile,
it must not be retried again now.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
BUG: unable to handle kernel NULL pointer dereference at (null)
...
[<d1e17561>] ? _drbd_bm_set_bits+0x151/0x240 [drbd]
[<d1e236f8>] ? receive_bitmap+0x4f8/0xbc0 [drbd]
This fixes an off-by-one error in the receive_bitmap() path,
if run-length encoded bitmap transfer is enabled.
If the bitmap is an exact multiple of PAGE_SIZE, which means the visible
capacity of the drbd device is an exact multiple of 128 MiB (for 4k page
size), and bitmap compression (use-rle) is enabled (which became default
with 8.4), and the very last bit is dirty and reported in an rle
comressed bitmap packet, we ended up trying to kmap_atomic a page pointer
that does not exist (bitmap->bm_pages[last index + 1]).
bug introduced by:
Date: Fri Jul 24 15:33:24 2009 +0200
set bits: optimize for complete last word, fix off-by-one-word corner case
made effective by:
Date: Thu Dec 16 00:32:38 2010 +0100
drbd: get rid of unused debug code
Long time ago, we had paranoia code in the bitmap that allocated one
extra word, assigned a magic value, and checked on every occasion that
the magic value was still unchanged.
That debug code is unused, the extra long word complicates code a bit.
Get rid of it.
No-one triggered this bug in the last few years, because a large subset
of our userbase is unaffected:
* typically the last few blocks of a device are not modified
frequently, and remain unset
* use-rle was disabled by default in drbd < 8.4
* those with slightly "odd" device sizes, or
* drbd internal meta data (which will skew the device size slightly,
thus makes it harder to have a bug relevant device size)
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Pull block driver updates from Jens Axboe:
"Here are the driver related changes for 3.5. It contains:
- The floppy changes from Jiri. Jiri is now also marked as the
maintainer of floppy.c, I shall be publically branding his forehead
with red hot iron at the next opportune moment.
- A batch of drbd updates and fixes from the linbit crew, as well as
fixes from others.
- Two small fixes for xen-blkfront courtesy of Jan."
* 'for-3.5/drivers' of git://git.kernel.dk/linux-block: (70 commits)
floppy: take over maintainership
floppy: remove floppy-specific O_EXCL handling
floppy: convert to delayed work and single-thread wq
xen-blkfront: module exit handling adjustments
xen-blkfront: properly name all devices
drbd: grammar fix in log message
drbd: check MODULE for THIS_MODULE
drbd: Restore the request restart logic
drbd: introduce a bio_set to allocate housekeeping bios from
drbd: remove unused define
drbd: bm_page_async_io: properly initialize page->private
drbd: use the newly introduced page pool for bitmap IO
drbd: add page pool to be used for meta data IO
drbd: allow bitmap to change during writeout from resync_finished
drbd: fix race between drbdadm invalidate/verify and finishing resync
drbd: fix resend/resubmit of frozen IO
drbd: Ensure that data_size is not 0 before using data_size-1 as index
drbd: Delay/reject other state changes while establishing a connection
drbd: move put_ldev from __req_mod() to the endio callback
drbd: fix WRITE_ACKED_BY_PEER_AND_SIS to not set RQ_NET_DONE
...
In 2009 Philip Reiser notied that a few users of netlink connector
interface needed a capability check and added the idiom
cap_raised(nsp->eff_cap, CAP_SYS_ADMIN) to a few of them, on the premise
that netlink was asynchronous.
In 2011 Patrick McHardy noticed we were being silly because netlink is
synchronous and removed eff_cap from the netlink_skb_params and changed
the idiom to cap_raised(current_cap(), CAP_SYS_ADMIN).
Looking at those spots with a fresh eye we should be calling
capable(CAP_SYS_ADMIN). The only reason I can see for not calling capable
is that it once appeared we were not in the same task as the caller which
would have made calling capable() impossible.
In the initial user_namespace the only difference between between
cap_raised(current_cap(), CAP_SYS_ADMIN) and capable(CAP_SYS_ADMIN) are a
few sanity checks and the fact that capable(CAP_SYS_ADMIN) sets
PF_SUPERPRIV if we use the capability.
Since we are going to be using root privilege setting PF_SUPERPRIV seems
the right thing to do.
The motivation for this that patch is that in a child user namespace
cap_raised(current_cap(),...) tests your capabilities with respect to that
child user namespace not capabilities in the initial user namespace and
thus will allow processes that should be unprivielged to use the kernel
services that are only protected with cap_raised(current_cap(),..).
To fix possible user_namespace issues and to just clean up the code
replace cap_raised(current_cap(), CAP_SYS_ADMIN) with
capable(CAP_SYS_ADMIN).
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Acked-by: Andrew G. Morgan <morgan@kernel.org>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Cc: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
THIS_MODULE is NULL only when drbd is compiled as built-in,
so the #ifdef CONFIG_MODULES should be #ifdef MODULE instead.
This fixes the warning:
drivers/block/drbd/drbd_main.c: In function ‘drbd_buildtag’:
drivers/block/drbd/drbd_main.c:4187:24: warning: the comparison will always evaluate as ‘true’ for the address of ‘__this_module’ will never be NULL [-Waddress]
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
It got lost with the commit 5a7bbad27a
"block: remove support for bio remapping from ->make_request"
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Don't rely on availability of bios from the global fs_bio_set,
we should use our own bio_set for meta data IO.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
If bm_page_async_io is advised to use a new page for I/O
(BM_AIO_COPY_PAGES is set), it will get it from a mempool.
Once the mempool has to dip into its reserves the page is
not reinitialized, i.e. page->private contains garbage, which
will lead to various problems once the I/O completes (dereferences
of NULL pointers, the submitting thread getting stuck in D-state,
...).
Signed-off-by: Arne Redlich <arne.redlich@googlemail.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
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>
When a resync or online verify is finished or aborted,
drbd does a bulk write-out of changed bitmap pages.
If *in that very moment* a new verify or resync is triggered,
this can race:
ASSERT( !test_bit(BITMAP_IO, &mdev->flags) ) in drbd_main.c
FIXME going to queue 'set_n_write from StartingSync' but 'write from resync_finished' still pending?
and similar.
This can be observed with e.g. tight invalidate loops in test scripts,
and probably has no real-life implication.
Still, that race can be solved by first quiescen the device,
before starting a new resync or verify.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>
This could be exploited by a peer which runs modified code.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>
One invocation in the endio handler is good enough,
we don't need mention it for each of the different ways
it calls __req_mod().
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Just because this request happened during a resync does
not mean it may pretend to have been barrier-acked.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
READ_RETRY_REMOTE_CANCELED needs to be grouped with the other _CANCELED
cases, not with CONNECTION_LOST_WHILE_PENDING, as that would complete
(fail) the bio even if the device became suspended.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
OOS_HANDED_TO_NETWORK should not be grouped with the various
*_CANCELED/*_FAILED cases.
Also, not only clear the RQ_NET_QUEUED flag, but also mark it RQ_NET_DONE,
so it can be distinguished from a local-only request even after that.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
We used to have a barrier implementation where barrier_nr 0 was
reserved. That is long gone. Just use the full sequence space.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
We assumed only bios with bi_idx == 0 would end up
in drbd_make_request().
That is wrong.
At least device mapper, in __clone_and_map(), may submit
clones only covering a partial bio, but sharing
the original bvec, by adjusting bi_idx and relevant
other bio members of the clone.
We used __bio_for_each_segment() in various places,
even though that is documented as
* drivers should not use the __ version unless they _really_ want to
* run through the entire bio and not just pending pieces
Impact: we would send the full bio bvec, even for the clone
with bi_idx > 0, which will cause data corruption on the
peer (because we submit wrong data at the clone offset),
and will cause a DRBD protocol error, disconnect/reconnect
and resync (thus fixing the corruption),
because the next package header would be expected right
in the middle of the sent data, causing DRBD magic mismatch.
Fix: drop the assert, and use bio_for_each_segment()
instead of the __ version.
Conflicts:
drbd/drbd_tracing.c
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
If a SyncTarget node gets a P_RS_DATA_REPLY before a P_DATA packet
for the same sector, it simply submits these two IO requests.
This is be possible because on the SyncSource node, the data of the
P_RS_DATA_REPLY packet was read from disk. Immediately after that a
write request from upper layers came in.
The disk scheduler or even the "hardware" queues on the disk drive might
reorder these writes.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
When we have a write request and a state change C_WF_BITMAP_S -> C_SYNC_SOURCE
at the same time, and it happens that the line
remote = remote && drbd_should_do_remote(s);
stills sees C_WF_BITMAP_S, and
send_oos = rw == WRITE && drbd_should_send_oos(s);
already sees C_SYNC_SOURCE both are 0.
This causes the write to not be mirrored, but marked as out-of-sync on the
Sync_Source node.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Without this, iostat frequently sees bogus svctime and >= 100% "utilization".
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
drbd_accept was modelled after kernel_accept
with drbd commit 53eb779 in July 2008.
Only, kernel_accept was then broken, and only fixed later
with kernel commit 1b08534e in Dec 2008:
net: Fix module refcount leak in kernel_accept()
Impact: protocol families provided as modules, e.g. ipv6 or ib_sdp,
would soon have their reference count become negative, preventing
them from being unloaded (likely), or worse, hit zero without actually
being unused, allowing them to be unloaded while still in use (unlikely,
but if triggered, causing a kernel crash).
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>
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>
If the asender thread, or request_timer_fn(), or some other part of
the code, decided to drop the connection (because of timeout or other),
but the receiver just now was processing a P_STATE packet, there was a
chance that receive_state() would do a hard state change
"re-establishing" an already failed connection without additional handshake.
Log excerpt:
Remote failed to finish a request within ko-count * timeout
peer( Secondary -> Unknown ) conn( Connected -> Timeout ) pdsk( UpToDate -> DUnknown )
asender terminated
...
peer( Unknown -> Secondary ) conn( Timeout -> Connected ) pdsk( DUnknown -> UpToDate ) peer_isp( 0 -> 1 )
...
Connection closed
peer( Secondary -> Unknown ) conn( Connected -> Unconnected ) pdsk( UpToDate -> DUnknown ) peer_isp( 1 -> 0 )
receiver terminated
Impact:
while the connection state is erroneously "Connected",
requests may be queued and even sent,
which would never be acknowledged,
and may have been missed by the cleanup.
These requests would never be completed.
The next drbd_suspend_io() will then lock up,
waiting forever for these requests to complete.
Fixed in several code paths:
Make sure the connection state is NetworkFailure or worse
before starting the cleanup in drbd_disconnect().
This should make sure the cleanup won't miss any requests.
Disallow receive_state() to "upgrade" the connection state
from an error state. This will make sure the "illegal" state
transition won't happen.
For all connection failure states,
relax the safe-guard in sanitize_state() again
to silently mask out those state changes
(e.g. Timeout -> Connected becomes Timeout -> Timeout).
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
drbd_try_clear_on_disk_bm() has a sanity check for the number of blocks
left to be resynced (rs_left) in the current resync extent.
If it detects a mismatch, it complains, and forces a disconnect using
drbd_force_state(mdev, NS(conn, C_DISCONNECTING));
Unfortunately, this may be called while holding the req_lock,
and drbd_force_state() want's to aquire that lock itself. Deadlock.
Don't force a disconnect, but fix up rs_left by recounting and
reassigning the number of dirty blocks in that extent.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This bug might have caused troubles if disk-barriers and the ahead-behind
more are enabled at the same time.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
DRBD state changes schedule after_state_ch() actions to a worker thread,
which decides on the old and new states of that change, whether to send
an informational state update packet (P_STATE) to the peer.
If it decides to drbd_send_state(), it would however always send the
_curent_ state, which, if a second state change happens before the
after_state_ch() of the first ran, may "fast-forward" the peer's view
about this node. In most cases that is harmless, but sometimes this can
confuse DRBD, for example into not actually starting a necessary resync
if you do a very tight detach/attach loop on a Connected Secondary.
Fix this by always sending the "new" state of the respective state
transition which scheduled this after_state_ch() work.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
When detaching, even cleanly detaching due to administrator request,
we always go through D_FAILED before we become D_DISKLESS.
Don't let that state change race with an in-flight meta data IO,
or that one might think it actually experienced an IO error.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
drbd_state_lock() is only there to serialize cluster wide state
changes. Testing the local disk state needs to happen while
holding the global_state_lock.
Otherwise you might see something like this (Oct 6 on kugel)
14:20:24 drbd0: conn( WFSyncUUID -> Connected ) disk( Inconsistent -> Failed )
14:20:24 drbd0: helper command: /sbin/drbdadm before-resync-target minor-0 exit code 0 (0x0)
14:20:24 drbd0: conn( Connected -> SyncTarget ) disk( Failed -> Inconsistent )
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
We have one pre-allocated page to do certain synchronous meta data IO with,
using it is serialized like so:
drbd_md_get_buffer();
drbd_md_sync_page_io();
drbd_md_sync_page_io();
...
drbd_md_put_buffer();
In drbd_md_sync_page_io() there is an
ASSERT(atomic_read(&mdev->md_io_in_use) == 1);
We want to be able to timeout on unresponsive lower level devices, so we
can "detach" in that case. Inside drbd_md_sync_page_io() we grab an extra
reference, to not have a dangling pointer in case a delayed IO eventually
does still complete, even after we "detached" already.
We need to put the extra reference before we signal completion from the
completion handler, or the second drbd_md_sync_page_io() above may
trigger the assert (reference count still 2).
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
With sync-after dependencies, given "lucky" timing of pause/unpause
events, and the end of an empty (0 bits set) resync was sometimes not
detected on the SyncTarget, leading to a "stalled" SyncSource state.
Fixed this by expecting not only "Inconsistent -> UpToDate" but also
"Consistent -> UpToDate" transitions for the peer disk state
to end a resync.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
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>
Lars Ellenberg