Commit Graph

413 Commits

Author SHA1 Message Date
Lars Ellenberg
db141b2f42 drbd: fix max_bio_size to be unsigned
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>
2012-07-24 15:14:00 +02:00
Lars Ellenberg
7ee1fb93f3 drbd: flush drbd work queue before invalidate/invalidate remote
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>
2012-07-24 14:15:58 +02:00
Lars Ellenberg
c2ba686f35 drbd: report congestion if we are waiting for some userland callback
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>
2012-07-24 14:07:18 +02:00
Lars Ellenberg
383606e0de drbd: differentiate between normal and forced detach
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>
2012-07-24 14:06:18 +02:00
Lars Ellenberg
d264580145 drbd: cleanup, remove two unused global flags
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-07-24 14:02:41 +02:00
Lars Ellenberg
9476f39d66 drbd: introduce a bio_set to allocate housekeeping bios from
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>
2012-05-09 15:17:07 +02:00
Lars Ellenberg
4281808fb3 drbd: add page pool to be used for meta data IO
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-05-09 15:17:02 +02:00
Lars Ellenberg
0e8488ade2 drbd: allow bitmap to change during writeout from resync_finished
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>
2012-05-09 15:17:00 +02:00
Lars Ellenberg
ba280c092e drbd: fix resend/resubmit of frozen IO
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>
2012-05-09 15:16:58 +02:00
Philipp Reisner
197296ffed drbd: Delay/reject other state changes while establishing a connection
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>
2012-05-09 15:16:55 +02:00
Lars Ellenberg
7ffcaa7194 drbd: remove unused static helper function
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-05-09 15:16:44 +02:00
Lars Ellenberg
a5d214f621 drbd: remove some very outdated comments
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-05-09 15:16:43 +02:00
Lars Ellenberg
671a74e749 drbd: remove now unused seq_num member from struct drbd_request
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-05-09 15:16:40 +02:00
Philipp Reisner
7caacb69ac drbd: Consider the disk-timeout also for meta-data IO operations
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>
2012-05-09 15:16:30 +02:00
Lars Ellenberg
f479ea0661 drbd: send intermediate state change results to the peer
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>
2012-05-09 15:15:56 +02:00
Philipp Reisner
5ca1de0384 drbd: Allow new IOs while the local disk in in FAILED state
The last bunch of commits prepared the 'detach from tar pit' feature.
With that we can be for long time in disk state FAILED. We need
to accept new IO requests during that time.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-05-09 15:10:34 +02:00
Philipp Reisner
0c46442515 drbd: Implemented wait_until_done_or_disk_failure()
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-05-09 10:26:51 +02:00
Philipp Reisner
e17117310b drbd: Replaced md_io_mutex by an atomic: md_io_in_use
The new function drbd_md_get_buffer() aborts waiting for the buffer
in case the disk failes in the meantime.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-05-09 10:22:31 +02:00
Philipp Reisner
cc94c65015 drbd: moved md_io into mdev
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-05-09 10:17:24 +02:00
Philipp Reisner
6d7e32f568 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>
2012-05-09 10:15:28 +02:00
David Howells
5f138ce01a DRBD: Fix comparison always false warning due to long/long long compare
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>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
2012-05-09 10:03:19 +02:00
Rusty Russell
90ab5ee941 module_param: make bool parameters really bool (drivers & misc)
module_param(bool) used to counter-intuitively take an int.  In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.

It's time to remove the int/unsigned int option.  For this version
it'll simply give a warning, but it'll break next kernel version.

Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13 09:32:20 +10:30
Linus Torvalds
b4fdcb02f1 Merge branch 'for-3.2/core' of git://git.kernel.dk/linux-block
* 'for-3.2/core' of git://git.kernel.dk/linux-block: (29 commits)
  block: don't call blk_drain_queue() if elevator is not up
  blk-throttle: use queue_is_locked() instead of lockdep_is_held()
  blk-throttle: Take blkcg->lock while traversing blkcg->policy_list
  blk-throttle: Free up policy node associated with deleted rule
  block: warn if tag is greater than real_max_depth.
  block: make gendisk hold a reference to its queue
  blk-flush: move the queue kick into
  blk-flush: fix invalid BUG_ON in blk_insert_flush
  block: Remove the control of complete cpu from bio.
  block: fix a typo in the blk-cgroup.h file
  block: initialize the bounce pool if high memory may be added later
  block: fix request_queue lifetime handling by making blk_queue_cleanup() properly shutdown
  block: drop @tsk from attempt_plug_merge() and explain sync rules
  block: make get_request[_wait]() fail if queue is dead
  block: reorganize throtl_get_tg() and blk_throtl_bio()
  block: reorganize queue draining
  block: drop unnecessary blk_get/put_queue() in scsi_cmd_ioctl() and blk_get_tg()
  block: pass around REQ_* flags instead of broken down booleans during request alloc/free
  block: move blk_throtl prototypes to block/blk.h
  block: fix genhd refcounting in blkio_policy_parse_and_set()
  ...

Fix up trivial conflicts due to "mddev_t" -> "struct mddev" conversion
and making the request functions be of type "void" instead of "int" in
 - drivers/md/{faulty.c,linear.c,md.c,md.h,multipath.c,raid0.c,raid1.c,raid10.c,raid5.c}
 - drivers/staging/zram/zram_drv.c
2011-11-04 17:06:58 -07:00
Lars Ellenberg
da4a75d2ef drbd: introduce a bio_set to allocate housekeeping bios from
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>
2011-10-14 16:48:06 +02:00
Lars Ellenberg
35abf59424 drbd: add page pool to be used for meta data IO
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:48:04 +02:00
Philipp Reisner
81a5d60ecf drbd: Replaced the minor_table array by an idr
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:48:01 +02:00
Philipp Reisner
774b305518 drbd: Implemented new commands to create/delete connections/minors
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:48:00 +02:00
Philipp Reisner
80883197da drbd: Converted drbd_nl_(net_conf|disconnect)() from mdev to tconn
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:48:00 +02:00
Philipp Reisner
1aba4d7fcf drbd: Preparing the connector interface to operator on connections
Up to now it only operated on minor numbers. Now it can work also
on named connections.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:47:59 +02:00
Philipp Reisner
2f5cdd0b2c drbd: Converted the transfer log from mdev to tconn
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:47:58 +02:00
Philipp Reisner
49559d87fd drbd: Improved the dec_*() macros
Now those can be used with a struct drbd_conf * that has an other
name than 'mdev'.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:47:57 +02:00
Philipp Reisner
0e29d163f7 drbd: Reworked the unconfiguring and thread stopping code
* Moved CONFIG_PENDING and DEVICE_DYING from mdev to tconn.
* Renamed drbd_reconfig_start() and drbd_reconfig_done() to
  conn_reconfig_start() and conn_reconfig_done().

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:47:55 +02:00
Andreas Gruenbacher
c66342d949 drbd: Remove left-over function prototypes
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:47:55 +02:00
Andreas Gruenbacher
6e849ce88c drbd: Get rid of P_MAX_CMD
Instead of artificially enlarging the command decoding arrays to
P_MAX_CMD entries, check if an index is within the valid range using the
ARRAY_SIZE() macro.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:47:53 +02:00
Andreas Gruenbacher
7be8da0798 drbd: Improve how conflicting writes are handled
The previous algorithm for dealing with overlapping concurrent writes
was generating unnecessary warnings for scenarios which could be
legitimate, and did not always handle partially overlapping requests
correctly.  Improve it algorithm as follows:

* While local or remote write requests are in progress, conflicting new
  local write requests will be delayed (commit 82172f7).

* When a conflict between a local and remote write request is detected,
  the node with the discard flag decides how to resolve the conflict: It
  will ask its peer to discard conflicting requests which are fully
  contained in the local request and retry requests which overlap only
  partially.  This involves a protocol change.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:47:51 +02:00
Lars Ellenberg
7ad651b522 drbd: new on-disk activity log transaction format
Use a new on-disk transaction format for the activity log, which allows
for multiple changes to the active set per transaction.

Using 4k transaction blocks, we can now get rid of the work-around code
to deal with devices not supporting 512 byte logical block size.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:47:46 +02:00
Lars Ellenberg
45dfffebd0 drbd: allow to select specific bitmap pages for writeout
We are about to allow several changes to the active set in one activity
log transaction. We have to write out the corresponding bitmap pages as
well, if changed.

Introduce drbd_bm_mark_for_writeout(), then re-use the existing bitmap
writeout path to submit all marked pages in one go.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:47:44 +02:00
Andreas Gruenbacher
fcefa62e4c drbd: Rename drbd_endio_{pri,sec} -> drbd_{,peer_}request_endio
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:47:36 +02:00
Andreas Gruenbacher
fbe29dec98 drbd: Rename drbd_submit_ee -> drbd_submit_peer_request
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:47:35 +02:00
Philipp Reisner
047cd4a682 drbd: implemented receiving of P_CONN_ST_CHG_REQ
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:45:05 +02:00
Philipp Reisner
fc3b10a45f drbd: Implemented receiving of P_CONN_ST_CHG_REPLY
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:45:04 +02:00
Philipp Reisner
cf29c9d8c8 drbd: Implemented conn_send_state_req()
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:45:02 +02:00
Philipp Reisner
8410da8f0e drbd: Introduced tconn->cstate_mutex
In compatibility mode with old DRBDs, use that as the state_mutex
as well.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:45:01 +02:00
Philipp Reisner
dad2055481 drbd: Removed drbd_state_lock() and drbd_state_unlock()
The lock they constructed is only taken when the state_mutex
was already taken. It is superficial.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:45:01 +02:00
Philipp Reisner
bbeb641c3e drbd: Killed volume0; last step of multi-volume-enablement
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-10-14 16:44:58 +02:00
Philipp Reisner
2a67d8b93b drbd: Converted drbd_send_ping() and related functions from mdev to tconn
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:33:16 +02:00
Philipp Reisner
00d56944ff drbd: Generalized the work callbacks
No longer work callbacks must operate on a mdev. From now on they
can also operate on a tconn.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:33:15 +02:00
Philipp Reisner
392c880192 drbd: drbd_thread has now a pointer to a tconn instead of to a mdev
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:33:13 +02:00
Philipp Reisner
a21e929827 drbd: Moved the mdev member into drbd_work (from drbd_request and drbd_peer_request)
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:33:08 +02:00
Philipp Reisner
360cc74052 drbd: Converted drbd_free_sock() and drbd_disconnect() from mdev to tconn
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:33:06 +02:00
Philipp Reisner
eefc2f7de2 drbd: Converted drbdd() from mdev to tconn
The drbd_md_sync(mdev) happens in the after state change anyways...

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:33:05 +02:00
Philipp Reisner
808222845d drbd: Converted drbd_calc_cpu_mask() and drbd_thread_current_set_cpu() from mdev to tconn
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:33:04 +02:00
Philipp Reisner
062e879c8b drbd: Use and idr data structure to map volume numbers to mdev pointers
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:33:02 +02:00
Philipp Reisner
dc8228d107 drbd: Converted drbd_send_protocol() from mdev to tconn
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:33:01 +02:00
Philipp Reisner
611208706f drbd: Converted drbd_(get|put)_data_sock() and drbd_send_cmd2() to tconn
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:32:59 +02:00
Philipp Reisner
8a22cccc20 drbd: Converted drbd_send_handshake() from mdev to tconn
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:29:50 +02:00
Philipp Reisner
d38e787ecc drbd: Converted drbd_send_fp() from mdev to tconn
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:29:45 +02:00
Philipp Reisner
bedbd2a53a drbd: Converted drbd_send() from mdev to tconn
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:27:00 +02:00
Philipp Reisner
0625ac190d drbd: Converted wake_asender() and request_ping() from mdev to tconn
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:58 +02:00
Philipp Reisner
808e37b803 drbd: Moved SIGNAL_ASENDER to the per connection (tconn) flags
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:57 +02:00
Philipp Reisner
e43ef195f8 drbd: Moved SEND_PING to the per connection (tconn) flags
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:56 +02:00
Philipp Reisner
25703f8320 drbd: Moved DISCARD_CONCURRENT to the per connection (tconn) flags
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:55 +02:00
Philipp Reisner
01a311a589 drbd: Started to separated connection flags (tconn) from block device flags (mdev)
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:54 +02:00
Philipp Reisner
60ae496626 drbd: conn_printk() a dev_printk() alike for drbd's connections
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:50 +02:00
Philipp Reisner
b53339fce2 drbd: Moving state related macros to drbd_state.h
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:49 +02:00
Philipp Reisner
e64a329459 drbd: Do no sleep long in drbd_start_resync
Work items that sleep too long can cause requests to take as
long as the longest sleeping work item.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:47 +02:00
Philipp Reisner
bc31fe3352 drbd: Eliminated the user of drbd_task_to_thread()
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:45 +02:00
Philipp Reisner
bed879ae90 drbd: Moved the thread name into the data structure
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:44 +02:00
Philipp Reisner
b890733953 drbd: Moved the state functions into its own source file
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:43 +02:00
Andreas Gruenbacher
db830c464b drbd: Local variable renames: e -> peer_req
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:42 +02:00
Andreas Gruenbacher
6c852beca1 drbd: Update some comments
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:41 +02:00
Andreas Gruenbacher
18b75d756b drbd: Clean up some left-overs
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:40 +02:00
Andreas Gruenbacher
f6ffca9f42 drbd: Rename struct drbd_epoch_entry to struct drbd_peer_request
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:39 +02:00
Andreas Gruenbacher
c6f7df42c9 drbd: Remove unused variable in struct drbd_conf
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:37 +02:00
Andreas Gruenbacher
5e4722645a drbd: _req_conflicts(): Get rid of the epoch_entries tree
Instead of keeping a separate tree for local and remote write requests
for finding requests and for conflict detection, use the same tree for
both purposes.  Introduce a flag to allow distinguishing the two
possible types of entries in this tree.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:32 +02:00
Andreas Gruenbacher
9e204cddaf drbd: Move some functions to where they are used
Move drbd_update_congested() to drbd_main.c, and drbd_req_new() and
drbd_req_free() to drbd_req.c: those functions are not used anywhere
else.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:28 +02:00
Andreas Gruenbacher
3e394da184 drbd: Move sequence number logic into drbd_receiver.c and simplify it
These things are only used there.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:27 +02:00
Andreas Gruenbacher
d876302306 drbd: Rename "enum drbd_packets" to "enum drbd_packet"
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:24 +02:00
Andreas Gruenbacher
f2ad906379 drbd: Move cmdname() out of drbd_int.h
There is no good reason for cmdname() to be an inline function.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:26:23 +02:00
Philipp Reisner
fd340c12c9 drbd: Use new header layout
The new header layout will only be used if the peer supports
it of course.

For the first packet and the handshake packet the old (h80)
layout is used for compatibility reasons.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-09-28 10:23:03 +02:00
Jesper Juhl
e5de063016 Remove unneeded version.h includes from drivers/block/
It was pointed out by 'make versioncheck' that some includes of
linux/version.h are not needed in drivers/block/.
This patch removes them.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-15 14:57:06 +02:00
Joe Perches
1d273b929c drbd: Use angle brackets for system includes
Use the normal include style.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-09-15 14:02:57 +02:00
Christoph Hellwig
5a7bbad27a block: remove support for bio remapping from ->make_request
There is very little benefit in allowing to let a ->make_request
instance update the bios device and sector and loop around it in
__generic_make_request when we can archive the same through calling
generic_make_request from the driver and letting the loop in
generic_make_request handle it.

Note that various drivers got the return value from ->make_request and
returned non-zero values for errors.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-09-12 12:12:01 +02:00
Philipp Reisner
c012949a40 drbd: Replaced all p_header80 with a generic p_header
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:30:26 +02:00
Philipp Reisner
191d3cc8d9 drbd: Made drbd_flush_workqueue() to take a tconn instead of an mdev
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:30:24 +02:00
Philipp Reisner
a0638456c6 drbd: moved crypto transformations and friends from mdev to tconn
sed -i \
       -e 's/mdev->cram_hmac_tfm/mdev->tconn->cram_hmac_tfm/g' \
       -e 's/mdev->integrity_w_tfm/mdev->tconn->integrity_w_tfm/g' \
       -e 's/mdev->integrity_r_tfm/mdev->tconn->integrity_r_tfm/g' \
       -e 's/mdev->int_dig_out/mdev->tconn->int_dig_out/g' \
       -e 's/mdev->int_dig_in/mdev->tconn->int_dig_in/g' \
       -e 's/mdev->int_dig_vv/mdev->tconn->int_dig_vv/g' \
       *.[ch]

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:30:23 +02:00
Philipp Reisner
87eeee41f8 drbd: moved req_lock and transfer log from mdev to tconn
sed -i \
       -e 's/mdev->req_lock/mdev->tconn->req_lock/g' \
       -e 's/mdev->unused_spare_tle/mdev->tconn->unused_spare_tle/g' \
       -e 's/mdev->newest_tle/mdev->tconn->newest_tle/g' \
       -e 's/mdev->oldest_tle/mdev->tconn->oldest_tle/g' \
       -e 's/mdev->out_of_sequence_requests/mdev->tconn->out_of_sequence_requests/g' \
       *.[ch]

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:30:15 +02:00
Philipp Reisner
31890f4ab2 drbd: moved agreed_pro_version, last_received and ko_count to tconn
sed -i \
       -e 's/mdev->agreed_pro_version/mdev->tconn->agreed_pro_version/g' \
       -e 's/mdev->last_received/mdev->tconn->last_received/g' \
       -e 's/mdev->ko_count/mdev->tconn->ko_count/g' \
       *.[ch]

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:27:07 +02:00
Philipp Reisner
e6b3ea83bc drbd: moved receiver, worker and asender from mdev to tconn
Patch mostly:
sed -i -e 's/mdev->receiver/mdev->tconn->receiver/g' \
       -e 's/mdev->worker/mdev->tconn->worker/g' \
       -e 's/mdev->asender/mdev->tconn->asender/g' \
       *.[ch]

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:27:06 +02:00
Philipp Reisner
e42325a576 drbd: moved data and meta from mdev to tconn
Patch mostly:

sed -i -e 's/mdev->data/mdev->tconn->data/g' \
       -e 's/mdev->meta/mdev->tconn->meta/g' \
       *.[ch]

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:27:05 +02:00
Philipp Reisner
b2fb6dbe52 drbd: moved net_cont and net_cnt_wait from mdev to tconn
Patch partly generated by:

sed -i -e 's/get_net_conf(mdev)/get_net_conf(mdev->tconn)/g' \
       -e 's/put_net_conf(mdev)/put_net_conf(mdev->tconn)/g' \
       -e 's/get_net_conf(odev)/get_net_conf(odev->tconn)/g' \
       -e 's/put_net_conf(odev)/put_net_conf(odev->tconn)/g' \
       *.[ch]

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:27:04 +02:00
Philipp Reisner
89e58e755e drbd: moved net_conf from mdev to tconn
Besides moving the struct member, everything else is generated by:

sed -i -e 's/mdev->net_conf/mdev->tconn->net_conf/g' \
       -e 's/odev->net_conf/odev->tconn->net_conf/g' \
       *.[ch]

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:27:03 +02:00
Philipp Reisner
2111438b30 drbd: Minimal struct drbd_tconn
Starting to dissolve the network connection from the actual
block devices.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:27:02 +02:00
Andreas Gruenbacher
841ce241fa drbd: Replace the ERR_IF macro with an assert-like macro
Remove the file name and line number from the syslog messages generated:
we have no duplicate function names, and no function contains the same
assertion more than once.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:26:57 +02:00
Andreas Gruenbacher
e77a0a5cc1 drbd: Convert all constants in enum drbd_thread_state to upper case
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:26:56 +02:00
Andreas Gruenbacher
8554df1c6d drbd: Convert all constants in enum drbd_req_event to upper case
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:26:55 +02:00
Andreas Gruenbacher
bb3bfe9614 drbd: Remove the unused hash tables
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:26:54 +02:00
Andreas Gruenbacher
8b946255f8 drbd: Use interval tree for overlapping epoch entry detection
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:26:53 +02:00
Andreas Gruenbacher
010f6e678f drbd: Put sector and size in struct drbd_epoch_entry into struct drbd_interval
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:26:52 +02:00
Andreas Gruenbacher
dac1389ccc drbd: Add read_requests tree
We do not do collision detection for read requests, but we still need to
look up the request objects when we receive a package over the network.
Using the same data structure for read and write requests results in
simpler code once the tl_hash and app_reads_hash tables are removed.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-29 11:26:31 +02:00
Andreas Gruenbacher
de696716e8 drbd: Use interval tree for overlapping write request detection
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-25 14:58:06 +02:00
Andreas Gruenbacher
ace652acf2 drbd: Put sector and size in struct drbd_request into struct drbd_interval
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-25 14:58:05 +02:00
Andreas Gruenbacher
d628769b3c drbd: Move drbd_free_tl_hash() to drbd_main()
This is the only place where this function is used.  Make it static.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-25 14:57:58 +02:00
Andreas Gruenbacher
579b57ed73 drbd: Magic reserved block_id value cleanup
The ID_VACANT definition has become entirely irrelevant by now.

The is_syncer_block_id() macro does not improve the code, so eliminated
it.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-25 14:57:57 +02:00
Andreas Gruenbacher
3980485361 drbd: Remove superfluous declaration
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-08-25 14:57:43 +02:00
Linus Torvalds
929cfdd5d3 Merge branch 'for-2.6.40/drivers' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.40/drivers' of git://git.kernel.dk/linux-2.6-block: (110 commits)
  loop: handle on-demand devices correctly
  loop: limit 'max_part' module param to DISK_MAX_PARTS
  drbd: fix warning
  drbd: fix warning
  drbd: Fix spelling
  drbd: fix schedule in atomic
  drbd: Take a more conservative approach when deciding max_bio_size
  drbd: Fixed state transitions after async outdate-peer-handler returned
  drbd: Disallow the peer_disk_state to be D_OUTDATED while connected
  drbd: Fix for the connection problems on high latency links
  drbd: fix potential activity log refcount imbalance in error path
  drbd: Only downgrade the disk state in case of disk failures
  drbd: fix disconnect/reconnect loop, if ping-timeout == ping-int
  drbd: fix potential distributed deadlock
  lru_cache.h: fix comments referring to ts_ instead of lc_
  drbd: Fix for application IO with the on-io-error=pass-on policy
  xen/p2m: Add EXPORT_SYMBOL_GPL to the M2P override functions.
  xen/p2m/m2p/gnttab: Support GNTMAP_host_map in the M2P override.
  xen/blkback: don't fail empty barrier requests
  xen/blkback: fix xenbus_transaction_start() hang caused by double xenbus_transaction_end()
  ...
2011-05-25 09:15:35 -07:00
Andrew Morton
0ddf72be4e drbd: fix warning
In file included from drivers/block/drbd/drbd_main.c:54:                        drivers/block/drbd/drbd_int.h:1190: warning: parameter has incomplete type

Forward declarations of enums do not work.

Fix it unpleasantly by moving the prototype.

Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Lars Ellenberg <drbd-dev@lists.linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2011-05-24 10:38:33 +02:00
Bart Van Assche
24c4830c8e drbd: Fix spelling
Found these with the help of ispell -l.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
2011-05-24 10:21:29 +02:00
Lars Ellenberg
9a0d9d0389 drbd: fix schedule in atomic
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.

manually picked commit 564040f from the drbd 8.4 branch.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-05-24 10:14:32 +02:00
Philipp Reisner
99432fcc52 drbd: Take a more conservative approach when deciding max_bio_size
The old (optimistic) implementation could shrink the bio size
on an primary device.

Shrinking the bio size on a primary device is bad. Since there
we might get BIOs with the old (bigger) size shortly after
we published the new size.

The new implementation is more conservative, and eventually
increases the max_bio_size on a primary device (which is valid).
It does so, when it knows the local limit AND the remote limit.

 We cache the last seen max_bio_size of the peer in the meta
 data, and rely on that, to make the operation of single
 nodes more efficient.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-05-24 10:08:58 +02:00
Philipp Reisner
d2e17807e3 drbd: Only downgrade the disk state in case of disk failures
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-05-24 10:05:48 +02:00
Philipp Reisner
738a84b25c drbd: Fix for application IO with the on-io-error=pass-on policy
In case a write failes on the local disk, go into D_INCONSISTENT
disk state. That causes future reads of that block to be shipped
to the peer.

Read retry remote was already in place.

Actually the documentation needs to get fixed now. Since the
application is still shielded from the error. (as long as we have
only a single disk failing) The difference to detach is that
we keep the disk. And therefore might keep all the other, still
working sectors up to date.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-05-24 09:59:49 +02:00
Paul Gortmaker
70c7160619 Add appropriate <linux/prefetch.h> include for prefetch users
After discovering that wide use of prefetch on modern CPUs
could be a net loss instead of a win, net drivers which were
relying on the implicit inclusion of prefetch.h via the list
headers showed up in the resulting cleanup fallout.  Give
them an explicit include via the following $0.02 script.

 =========================================
 #!/bin/bash
 MANUAL=""
 for i in `git grep -l 'prefetch(.*)' .` ; do
 	grep -q '<linux/prefetch.h>' $i
 	if [ $? = 0 ] ; then
 		continue
 	fi

 	(	echo '?^#include <linux/?a'
 		echo '#include <linux/prefetch.h>'
 		echo .
 		echo w
 		echo q
 	) | ed -s $i > /dev/null 2>&1
 	if [ $? != 0 ]; then
 		echo $i needs manual fixup
 		MANUAL="$i $MANUAL"
 	fi
 done
 echo ------------------- 8\<----------------------
 echo vi $MANUAL
 =========================================

Signed-off-by: Paul <paul.gortmaker@windriver.com>
[ Fixed up some incorrect #include placements, and added some
  non-network drivers and the fib_trie.c case    - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-22 21:41:57 -07:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Philipp Reisner
7fde2be930 drbd: Implemented real timeout checking for request processing time
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:48:16 +01:00
Lars Ellenberg
20ceb2b22e drbd: describe bitmap locking for bulk operation in finer detail
Now that we do no longer in-place endian-swap the bitmap, we allow
selected bitmap operations (testing bits, sometimes even settting bits)
during some bulk operations.

This caused us to hit a lot of FIXME asserts similar to
	FIXME asender in drbd_bm_count_bits,
	bitmap locked for 'write from resync_finished' by worker
Which now is nonsense: looking at the bitmap is perfectly legal
as long as it is not being resized.

This cosmetic patch defines some flags to describe expectations in finer
detail, so the asserts in e.g. bm_change_bits_to() can be skipped if
appropriate.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:48:02 +01:00
Lars Ellenberg
62b0da3a24 drbd: log UUIDs whenever they change
All decisions about sync, sync direction, and wether or not to
allow a connect or attach are based on our set of UUIDs to tag a
data generation.

Log changes to the UUIDs whenever they occur,
logging "new current UUID P:Q:R:S" is more useful
than "Creating new current UUID".

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:48:01 +01:00
Philipp Reisner
370a43e798 drbd: Work on the Ahead -> SyncSource transition
The test if rs_pending_cnt == 0 was too weak. Using Test for
unacked_cnt == 0 instead. Moved that into the worker.

Since unacked_cnt gets already increased when an P_RS_DATA_REQ
comes in.

Also using a timer to make Ahead -> SyncSource -> Ahead cycles
slower...

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:45:36 +01:00
Philipp Reisner
4a23f26496 drbd: Do not full sync if a P_SYNC_UUID packet gets lost
See also commit from 2009-08-15
"drbd_uuid_compare(): Do not full sync in case a P_SYNC_UUID packet gets lost."

We saw cases where the History UUIDs where not as expected. So the
detection of the special case did not trigger. With the sync UUID
no longer being a random number, but deducible from the previous
bitmap UUID, the detection of this special case becomes more
reliable.

The SyncUUID now is the previous bitmap UUID + 0x1000000000000.

Rule 5a:
Cs = H1p & H1p + Offset = Bp
  Connection was lost before SyncUUID Packet came through.
  Corrent (peer) UUIDs:
   Bp = H1p
   H1p = H2p
   H2p = 0
  Become Sync target.

Rule 7a:
Cp = H1s & H1s + Offset = Bs
  Connection was lost before SyncUUID Packet came through.
  Correct (own) UUIDs:
   Bs = H1s
   H1s = H2s
   H2s = 0
  Become Sync source.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:45:32 +01:00
Andreas Gruenbacher
110a204a35 drbd: Remove useless / wrong comments
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:45:29 +01:00
Philipp Reisner
794abb753e drbd: Cleaned up the resync timer logic
Besides removed a few lines of code, this moves the inspection
of the state from before the queuing process to after the queuing.
I.e. more closely to the actual invocation of the work.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:45:28 +01:00
Philipp Reisner
d612d309e4 drbd: No longer answer P_RS_DATA_REQUEST packets when in C_AHEAD mode
When the sync source node replies to a P_RS_DATA_REQUEST packet
when it is already in ahead mode. I.e. those two packets
crossed each other on the wire, that may lead to diverging
bitmaps.

  This never happens in a well-tuned-system. In a well-tuned-
  system the resync controller has reduced the resync speed
  to zero long before we got into ahead-mode.

But we have to be prepared for the not-well-tuned-system
of course as well.
Because -> diverging bitmaps = non terminating resync.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:45:25 +01:00
Lars Ellenberg
5a22db8968 drbd: serialize sending of resync uuid with pending w_send_oos
To improve the latency of IO requests during bitmap exchange,
we recently allowed writes while waiting for the bitmap, sending "set
out-of-sync" information packets for any newly dirtied bits.

We have to make sure that the new resync-uuid does not overtake
these "set oos" packets. Once the resync-uuid is received, the
sync target starts the resync process, and expects the bitmap to
only be cleared, not re-set.

If we use this protocol extension, we queue the generation and sending
of the resync-uuid on the worker, which naturally serializes with all
previously queued packets.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:43:35 +01:00
Lars Ellenberg
4b0715f096 drbd: allow petabyte storage on 64bit arch
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:43:24 +01:00
Lars Ellenberg
19f843aa08 drbd: bitmap keep track of changes vs on-disk bitmap
When we set or clear bits in a bitmap page,
also set a flag in the page->private pointer.

This allows us to skip writes of unchanged pages.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:43:19 +01:00
Andreas Gruenbacher
1b881ef775 drbd: Rename __inc_ap_bio_cond to may_inc_ap_bio
The old name is confusing: the function does not increment anything.
Also rename _inc_ap_bio_cond to inc_ap_bio_cond: there is no need for
an underscore.
Finally, make it clear that these functions return boolean values.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:36:37 +01:00
Andreas Gruenbacher
81e84650c2 drbd: Use the standard bool, true, and false keywords
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:36:24 +01:00
Andreas Gruenbacher
bf885f8a67 drbd: Be more explicit about functions that return an enum drbd_state_rv
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:36:19 +01:00
Andreas Gruenbacher
0cf9d27e38 drbd: Get rid of unnecessary macros (2)
The FAULT_ACTIVE macro just wraps the drbd_insert_fault macro for no
apparent reason.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:36:15 +01:00
Andreas Gruenbacher
2f58dcfc85 drbd: Rename drbd_make_request_26 to drbd_make_request
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:36:11 +01:00
Andreas Gruenbacher
96756784a6 drbd: Remove left-over prototype
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:36:10 +01:00
Philipp Reisner
3719094ec2 drbd: Starting with protocol 96 we can allow app-IO while receiving the bitmap
* C_STARTING_SYNC_S, C_STARTING_SYNC_T In these states the bitmap gets
  written to disk. Locking out of app-IO is done by using the
  drbd_queue_bitmap_io() and drbd_bitmap_io() functions these days.
  It is no longer necessary to lock out app-IO based on the connection
  state.
  App-IO that may come in after the BITMAP_IO flag got cleared before the
  state transition to C_SYNC_(SOURCE|TARGET) does not get mirrored, sets
  a bit in the local bitmap, that is already set, therefore changes nothing.

* C_WF_BITMAP_S In this state we send updates (P_OUT_OF_SYNC packets).
  With that we make sure they have the same number of bits when going
  into the C_SYNC_(SOURCE|TARGET) connection state.

* C_UNCONNECTED: The receiver starts, no need to lock out IO.

* C_DISCONNECTING: in drbd_disconnect() we had a wait_event()
  to wait until ap_bio_cnt reaches 0. Removed that.

* C_TIMEOUT, C_BROKEN_PIPE, C_NETWORK_FAILURE
  C_PROTOCOL_ERROR, C_TEAR_DOWN: Same as C_DISCONNECTING

* C_WF_REPORT_PARAMS: IO still possible since that is still
  like C_WF_CONNECTION.

And we do not need to send barriers in C_WF_BITMAP_S connection state.

Allow concurrent accesses to the bitmap when receiving the bitmap.
Everything gets ORed anyways.

A drbd_free_tl_hash() is in after_state_chg_work(). At that point
all the work items of the last connections must have been processed.

Introduced a call to drbd_free_tl_hash() into drbd_free_mdev()
for paranoia reasons.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:35:06 +01:00
Philipp Reisner
8869d683b7 drbd: Fixed inc_ap_bio()
The condition must be checked after perpare_to_wait(). The old
implementaion could loose wakeup events. Never observed in real
life.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:35:01 +01:00
Philipp Reisner
9d77a5fee9 drbd: Make some functions static
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:34:54 +01:00
Philipp Reisner
e3555d8545 drbd: Implemented priority inheritance for resync requests
We only issue resync requests if there is no significant application IO
going on. = Application IO has higher priority than resnyc IO.

If application IO can not be started because the resync process locked
an resync_lru entry, start the IO operations necessary to release the
lock ASAP.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:34:53 +01:00
Philipp Reisner
c4752ef128 drbd: When proxy's buffer drained off go into regular resync mode
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:34:49 +01:00
Philipp Reisner
73a01a18b9 drbd: New packet for Ahead/Behind mode: P_OUT_OF_SYNC
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:34:48 +01:00
Philipp Reisner
67531718d8 drbd: Implemented two new connection states Ahead/Behind
In this connection mode, the ahead node no longer replicates
application IO. The behind's disk becomes out dated.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:34:46 +01:00
Philipp Reisner
759fbdfba6 drbd: Track the numbers of sectors in flight
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:34:43 +01:00
Lars Ellenberg
1816a2b47a drbd: properly use max_hw_sectors to limit the our bio size
To ease tracking of bios in some hash tables, we want it to
not cross certain boundaries (128k, used to be 32k).
We limit the maximum bio size using queue parameters.

Historically some defines and variables we use there have been named
max_segment_size, which was misguided. Rename them to max_bio_size,
and use [blk_]queue_max_hw_sectors where appropriate.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:19:11 +01:00
Lars Ellenberg
9bd28d3c90 drbd: factor out drbd_rs_controller_reset
Preparation patch to be able to use the auto-throttling resync controller
for online-verify requests as well.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:18:59 +01:00
Lars Ellenberg
439d595379 drbd: show progress bar and ETA for online-verify
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:18:58 +01:00
Lars Ellenberg
ea5442aff6 drbd: advance progress step marks for online-verify
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2011-03-10 11:18:56 +01:00
Jens Axboe
721a9602e6 block: kill off REQ_UNPLUG
With the plugging now being explicitly controlled by the
submitter, callers need not pass down unplugging hints
to the block layer. If they want to unplug, it's because they
manually plugged on their own - in which case, they should just
unplug at will.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-10 08:52:27 +01:00
Jens Axboe
7eaceaccab block: remove per-queue plugging
Code has been converted over to the new explicit on-stack plugging,
and delay users have been converted to use the new API for that.
So lets kill off the old plugging along with aops->sync_page().

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-10 08:52:07 +01:00
Jens Axboe
f30195c502 Merge branch 'cleanup-bd_claim' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc into for-2.6.38/core 2010-11-27 19:49:18 +01:00
Tejun Heo
e525fd89d3 block: make blkdev_get/put() handle exclusive access
Over time, block layer has accumulated a set of APIs dealing with bdev
open, close, claim and release.

* blkdev_get/put() are the primary open and close functions.

* bd_claim/release() deal with exclusive open.

* open/close_bdev_exclusive() are combination of open and claim and
  the other way around, respectively.

* bd_link/unlink_disk_holder() to create and remove holder/slave
  symlinks.

* open_by_devnum() wraps bdget() + blkdev_get().

The interface is a bit confusing and the decoupling of open and claim
makes it impossible to properly guarantee exclusive access as
in-kernel open + claim sequence can disturb the existing exclusive
open even before the block layer knows the current open if for another
exclusive access.  Reorganize the interface such that,

* blkdev_get() is extended to include exclusive access management.
  @holder argument is added and, if is @FMODE_EXCL specified, it will
  gain exclusive access atomically w.r.t. other exclusive accesses.

* blkdev_put() is similarly extended.  It now takes @mode argument and
  if @FMODE_EXCL is set, it releases an exclusive access.  Also, when
  the last exclusive claim is released, the holder/slave symlinks are
  removed automatically.

* bd_claim/release() and close_bdev_exclusive() are no longer
  necessary and either made static or removed.

* bd_link_disk_holder() remains the same but bd_unlink_disk_holder()
  is no longer necessary and removed.

* open_bdev_exclusive() becomes a simple wrapper around lookup_bdev()
  and blkdev_get().  It also has an unexpected extra bdev_read_only()
  test which probably should be moved into blkdev_get().

* open_by_devnum() is modified to take @holder argument and pass it to
  blkdev_get().

Most of bdev open/close operations are unified into blkdev_get/put()
and most exclusive accesses are tested atomically at the open time (as
it should).  This cleans up code and removes some, both valid and
invalid, but unnecessary all the same, corner cases.

open_bdev_exclusive() and open_by_devnum() can use further cleanup -
rename to blkdev_get_by_path() and blkdev_get_by_devt() and drop
special features.  Well, let's leave them for another day.

Most conversions are straight-forward.  drbd conversion is a bit more
involved as there was some reordering, but the logic should stay the
same.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Neil Brown <neilb@suse.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Peter Osterlund <petero2@telia.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Alex Elder <aelder@sgi.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: dm-devel@redhat.com
Cc: drbd-dev@lists.linbit.com
Cc: Leo Chen <leochen@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Joern Engel <joern@logfs.org>
Cc: reiserfs-devel@vger.kernel.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
2010-11-13 11:55:17 +01:00
Jens Axboe
00e375e7e9 Merge branch 'for-2.6.37/drivers' into for-linus
Conflicts:
	drivers/block/cciss.c

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-11-10 14:51:27 +01:00
Mike Snitzer
77304d2aba block: read i_size with i_size_read()
Convert direct reads of an inode's i_size to using i_size_read().

i_size_{read,write} use a seqcount to protect reads from accessing
incomple writes.  Concurrent i_size_write()s require mutual exclussion
to protect the seqcount that is used by i_size_{read,write}.  But
i_size_read() callers do not need to use additional locking.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: NeilBrown <neilb@suse.de>
Acked-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-11-10 14:40:53 +01:00
Jens Axboe
53c2eb24ff Merge branch 'for-jens' of git://git.drbd.org/linux-2.6-drbd into for-2.6.37/drivers 2010-10-23 18:43:55 +02:00
Philipp Reisner
650789c87f drbd: Removed checks for REQ_HARDBARRIER on incomming BIOs
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-23 13:02:34 +02:00
Philipp Reisner
a8a4e51e69 drbd: REQ_HARDBARRIER -> REQ_FUA transition for meta data accesses
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-23 13:01:45 +02:00
Philipp Reisner
2451fc3b2b drbd: Removed the BIO_RW_BARRIER support form the receiver/epoch code
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-23 13:00:48 +02:00
Linus Torvalds
a2887097f2 Merge branch 'for-2.6.37/barrier' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.37/barrier' of git://git.kernel.dk/linux-2.6-block: (46 commits)
  xen-blkfront: disable barrier/flush write support
  Added blk-lib.c and blk-barrier.c was renamed to blk-flush.c
  block: remove BLKDEV_IFL_WAIT
  aic7xxx_old: removed unused 'req' variable
  block: remove the BH_Eopnotsupp flag
  block: remove the BLKDEV_IFL_BARRIER flag
  block: remove the WRITE_BARRIER flag
  swap: do not send discards as barriers
  fat: do not send discards as barriers
  ext4: do not send discards as barriers
  jbd2: replace barriers with explicit flush / FUA usage
  jbd2: Modify ASYNC_COMMIT code to not rely on queue draining on barrier
  jbd: replace barriers with explicit flush / FUA usage
  nilfs2: replace barriers with explicit flush / FUA usage
  reiserfs: replace barriers with explicit flush / FUA usage
  gfs2: replace barriers with explicit flush / FUA usage
  btrfs: replace barriers with explicit flush / FUA usage
  xfs: replace barriers with explicit flush / FUA usage
  block: pass gfp_mask and flags to sb_issue_discard
  dm: convey that all flushes are processed as empty
  ...
2010-10-22 17:07:18 -07:00
Lars Ellenberg
82f59cc635 drbd: fix potential deadlock on detach
If we have contention in drbd_al_begin_iod (heavy randon IO),
an administrative request to detach the disk may deadlock
for similar reasons as the recently fixed deadlock if detaching
because of IO-error.

The approach taken here is to either go through the intermediate
cleanup state D_FAILED, or first lock out application io,
don't just go directly to D_DISKLESS.

We need an additional state bit (WAS_IO_ERROR) to distinguish
the -> D_FAILED because of IO-error from other failures.

Sanitize D_ATTACHING -> D_FAILED to D_ATTACHING -> D_DISKLESS.
If only attaching, ldev may be missing still, but would be referenced
from within the after_state_ch for -> D_FAILED, potentially
dereferencing a NULL pointer.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-22 15:46:11 +02:00
Lars Ellenberg
3beec1d446 drbd: tag a few error messages with "assert failed"
If those messages ever get logged, clearly state that they are
actually failed ASSERTS, so our regression tests can pick them up
from the logs more easily.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-22 15:41:20 +02:00
Lars Ellenberg
e9e6f3ec53 drbd: fix for possible deadlock on IO error during resync
Scenario:

Something (say, flush-147:0) is in drbd_al_begin_io,
holding a local_cnt, waiting for the resync to make progress.

Disk fails, worker in after_state_ch does drbd_rs_cancel_all,
then waits for local_cnt to drop to zero.

flush-147:0 is woken by drbd_rs_cancel_all, needs to write an AL
transaction, and queues that on the worker.

Deadlock.

Fix: do not wait in the worker, have put_ldev() trigger the
state change D_FAILED -> D_DISKLESS when necessary.
put_ldev() cannot do the state change directly, as it may or may not
already hold various spinlocks. We queue a short work instead.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:50 +02:00
Lars Ellenberg
2b2bf2148f drbd: drbd_send_ack_dp must not rely on header information
drbd commit 17c854fea474a5eb3cfa12e4fb019e46debbc4ec
drbd: receiving of big packets, for payloads between 64kByte and 4GByte
introduced a new on-the-wire packet header format.  We must no longer
assume either format, but use the result of whatever drbd_recv_header
has decoded.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:45 +02:00
Philipp Reisner
00b425377d drbd: Allow larger values for c-fill-target.
Connections through a compressing proxy might have more bits
on the fly. 500MByte instead of 50MByte

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:42 +02:00
Philipp Reisner
fb22c402ff drbd: Track the reasons to suspend IO in dedicated state bits
There are three ways to get IO suspended:

 * Loss of any access to data
 * Fence-peer-handler running
 * User requested to suspend IO

Track those in different bits, so that one condition clearing its
state bit does not interfere with the other two conditions.

Only when the user resumes IO he overrules all three bits.

The fact is hidden from the user, he sees only a single suspend
bit.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:40 +02:00
Lars Ellenberg
435f07402b drbd: don't count sendpage()d pages only referenced by tcp as in use
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:33 +02:00
Philipp Reisner
76d2e7eca8 drbd: Adding support for BIO/Request flags: REQ_FUA, REQ_FLUSH and REQ_DISCARD
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:32 +02:00
Lars Ellenberg
ee15b03816 drbd: fix race on meta-data update, addendum
addendum to baa33ae4eaa4477b60af7c434c0ddd1d182c1ae7

The race:
    drbd_md_sync()
	if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
		return;
    ==> RACE with drbd_md_mark_dirty() rearming the timer.
	del_timer(&mdev->md_sync_timer);

    Fixed by moving the del_timer before the test_and_clear_bit.

Additionally only rearm the timer in drbd_md_mark_dirty, if MD_DIRTY was
not already set, reduce the grace period from five to one second, and
add an ifdef'ed debuging aid to find code paths missing an explicit
drbd_md_sync, if any, as those are the only relevant ones for this race.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:30 +02:00
Philipp Reisner
63106d3c6c drbd: Removed a race that could cause unexpected execution of w_make_resync_request()
The actual race happened int the drbd_start_resync() function. Where
drbd_resync_finished() -> __drbd_set_state() set STOP_SYNC_TIMER and
armed the timer.

If the timer fired before execution reaches the mod_timer statement
at the end of drbd_start_resync() the latter would cause an
unexpected call to w_make_resync_request().

Removed the STOP_SYNC_TIMER bit, and base it on the connection state.

The STOP_SYNC_TIMER bit probably originates probably the time before
the state engine.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:29 +02:00
Philipp Reisner
0778286a13 drbd: Disable activity log updates when the whole device is out of sync
When the complete device is marked as out of sync, we can disable
updates of the on disk AL. Currently AL updates are only disabled
if one uses the "invalidate-remote" command on an unconnected,
primary device, or when at attach time all bits in the bitmap are
set.

As of now, AL updated do not get disabled when a all bits becomes
set due to application writes to an unconnected DRBD device.
While this is a missing feature, it is not considered important,
and might get added later.

BTW, after initializing a "one legged" DRBD device
drbdadm create-md resX
drbdadm -- --force primary resX
AL updates also get disabled, until the first connect.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:26 +02:00
Philipp Reisner
d53733893d drbd: Actually allow BIOs up to 128k (was 32k).
Now we have multiple BIOs per ee, packets with a 32 bit length field,
it gets time to use these goodies.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:25 +02:00
Philipp Reisner
02918be227 drbd: receiving of big packets, for payloads between 64kByte and 4GByte
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:24 +02:00
Philipp Reisner
0b70a13dac drbd: Sending of big packets, for payloads from 64KByte to 4GByte
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:23 +02:00
Lars Ellenberg
0f0601f4ea drbd: new configuration parameter c-min-rate
We now track the data rate of locally submitted resync related requests,
and can thus detect non-resync activity on the lower level device.

If the current sync rate is above c-min-rate, and the lower level device
appears to be busy, we throttle the resyncer.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:20 +02:00
Lars Ellenberg
1d7734a0df drbd: use rolling marks for resync speed calculation
The current resync speed as displayed in /proc/drbd fluctuates a lot.
Using an array of rolling marks makes this calculation much more stable.
We used to have this (a long time ago with 0.7), but it got lost somehow.

If "stalled", do not discard the rest of the information, just add a
" (stalled)" tag to the progress line.

This patch also shortens a spinlock critical section somewhat, and
reduces the number of atomic operations in put_ldev.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:18 +02:00
Lars Ellenberg
0bb70bf601 drbd: remove outdated comment and dead code
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:17 +02:00
Lars Ellenberg
c36c3ced69 drbd: let drbd_free_ee implicitly free any digest
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:16 +02:00
Philipp Reisner
85719573dd drbd: Replaced some casts by an union. Improved comments
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:15 +02:00
Philipp Reisner
778f271dfe drbd: The new, smarter resync speed controller
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:14 +02:00
Philipp Reisner
8e26f9ccb9 drbd: New sync_param packet, that includes the parameters of the new controller
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 18:38:13 +02:00
Philipp Reisner
f70b351159 drbd: Do not try to free tl_hash in drbd_disconnect() when IO is suspended
We may not free tl_hash when IO is suspended, since we can not wait
until ap_bio_cnt reaches zero.

We can do this after susp reched 0, since then tl_clear was called

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 15:08:27 +02:00
Philipp Reisner
84dfb9f564 drbd: Fixed a deadlock, probably only affected UP machines
After disconnect (most likely mdev->net_cnt == 0) and we are
still in an unstable state (!drbd_state_is_stable()). When we
get an IO request in drbd_get_max_buffers() (called from
__inc_ap_bio_cond(), called from inc_ap_bio()) we wake up
misc_wait. Misc_wait is also used in inc_ap_bio() to sleep
until the outcome of __inc_ap_bio_cond() changes. => Busy loop!

Solution: Have a dedicated wait queue for get_net_conf() and
put_net_conf().

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 15:04:46 +02:00
Philipp Reisner
43a5182ccc drbd: Delayed creation of current-UUID
When a fencing policy of "resource-and-stonith" is configured,
and DRBD looses connection to it's peer, we can delay the
creation of a new current-UUID until IO gets thawed.

That allows one to deploy fence-peer handlers that actually
commit suicide on the machine they get started.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 14:59:21 +02:00
Philipp Reisner
87f7be4cf8 drbd: Run the fence-peer helper asynchronously
Since we can not thaw the transfer log, the next logical step is
to allow reconnects while the fence-peer handler runs.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 14:58:36 +02:00
Philipp Reisner
265be2d098 drbd: Finished the "on-no-data-accessible suspend-io;" functionality
When no data is accessible (no connection to the peer, nor a local disk)
allow the user to select to freeze all IO operations instead of getting
IO errors.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 14:52:53 +02:00
Philipp Reisner
11b58e73a3 drbd: factored tl_restart() out of tl_clear().
If IO was frozen for a temporal network outage, resend the
content of the transfer-log into the newly established connection.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 14:35:58 +02:00
Philipp Reisner
7e602c0aaf drbd: renamed drbd_tl_epoch.n_req to drbd_tl_epoch.n_writes
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-10-14 14:23:45 +02:00
Christoph Hellwig
dd3932eddf block: remove BLKDEV_IFL_WAIT
All the blkdev_issue_* helpers can only sanely be used for synchronous
caller.  To issue cache flushes or barriers asynchronously the caller needs
to set up a bio by itself with a completion callback to move the asynchronous
state machine ahead.  So drop the BLKDEV_IFL_WAIT flag that is always
specified when calling blkdev_issue_* and also remove the now unused flags
argument to blkdev_issue_flush and blkdev_issue_zeroout.  For
blkdev_issue_discard we need to keep it for the secure discard flag, which
gains a more descriptive name and loses the bitops vs flag confusion.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-16 20:52:58 +02:00
Lars Ellenberg
e7f52dfb4f drbd: revert "delay probes", feature is being re-implemented differently
It was a now abandoned attempt to throttle resync bandwidth
based on the delay it causes on the bulk data socket.
It has no userbase yet, and has been disabled by
9173465ccb51c09cc3102a10af93e9f469a0af6f already.
This removes the now unused code.

The basic feature, namely using up "idle" bandwith
of network and disk IO subsystem, with minimal impact
to application IO, is being reimplemented differently.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:53:57 +02:00
Lars Ellenberg
7383506c87 drbd: use drbd specific ratelimit instead of global printk_ratelimit
using the global printk_ratelimit() may mask other messages.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-06-01 11:12:27 +02:00
Philipp Reisner
32fa7e91f9 drbd: Removed the now empty w_io_error() function
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-06-01 11:12:27 +02:00
Lars Ellenberg
344fa462e3 drbd: improve network latency, TCP_QUICKACK
On Thu, Apr 29, 2010 at 04:00:50PM -0400, Eduard.Guzovsky@stratus.com
 wrote on drbd-dev@lists.linbit.com
 Subject: [Drbd-dev] DRBD small synchronous writes performance improvements

> 1. TCP_QUICKACK option is set incorrectly. The goal was force TCP to
> send and ACK as a  "one time" event.  Instead the code permanently sets
> connection in the QUICKACK mode.

He is right, we actually want to use an even val with TCP_QUICKACK.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-06-01 11:12:27 +02:00
Philipp Reisner
2c8d196759 drbd: Revert "drbd: Create new current UUID as late as possible"
The late-UUID writing is delayed until the next release.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-06-01 11:12:26 +02:00
Philipp Reisner
0c3f34516e drbd: Create new current UUID as late as possible
The choice was to either delay creation of the new UUID until
IO got thawed or to delay it until the first IO request.

Both are correct, the later is more friendly to users of
dual-primary setups, that actually only write on one side.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 02:03:49 +02:00
Philipp Reisner
9a25a04c80 drbd: If we detect late that IO got frozen, retry after we thawed.
If we detect late (= after grabing mdev->req_lock) that IO got frozen, we
return 1 to generic_make_request(), which simply will retry to make a
request for that bio.

In the subsequent call of generic_make_request() into drbd_make_request_26()
we sleep in inc_ap_bio().

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 02:03:32 +02:00
Lars Ellenberg
45bb912bd5 drbd: Allow drbd_epoch_entries to use multiple bios.
This should allow for better performance if the lower level IO stack
of the peers differs in limits exposed either via the queue,
or via some merge_bvec_fn.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 02:01:23 +02:00
Lars Ellenberg
708d740ed8 drbd: reduce sizeof struct drbd_epoch_entry by 8 byte by aligning members
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 01:28:35 +02:00
Philipp Reisner
162f3ec7f0 drbd: Fixes to the new delay_probes code
* Only send delay_probes with protocol 93 or newer
* drbd_send_delay_probes() is called only from worker context,
  no atomic_t needed for delay_seq

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 01:28:08 +02:00
Philipp Reisner
a8cdfd8d3b drbd: A fixes to the new resync speed code
* Mention P_DELAY_PROBE in the packet naming array
* Do not corrupt the mdev->data.work list in case the timer goes
  off before delay_probe_work got handled by the worker
* Do not mod_timer() twice for a single delay_probe pair

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 01:26:51 +02:00
Philipp Reisner
bd26bfc5b4 drbd: Actually send delay probes
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 01:25:28 +02:00
Philipp Reisner
7237bc430f drbd: Sending of delay_probes
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 01:22:46 +02:00
Philipp Reisner
0ced55a3be drbd: Receiving of delay_probes
Delay_probes are new packets in the DRBD protocol, which allow
DRBD to know the current delay packets have on the data socket.
(relative to the meta data socket)

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 01:22:11 +02:00
Philipp Reisner
6b4388ac1f drbd: Added transmission faults to the fault injection code
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 01:19:51 +02:00
Philipp Reisner
e89b591c3a drbd: Implemented flags for the resize packet
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 01:15:44 +02:00
Philipp Reisner
02d9a94bbb drbd: Implemented the set_new_bits parameter for drbd_bm_resize()
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 01:14:43 +02:00
Philipp Reisner
d845030f21 drbd: made determin_dev_size's parameter an flag enum
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-05-18 01:14:04 +02:00
Dmitry Monakhov
fbd9b09a17 blkdev: generalize flags for blkdev_issue_fn functions
The patch just convert all blkdev_issue_xxx function to common
set of flags. Wait/allocation semantics preserved.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-04-28 19:47:36 +02:00
Jens Axboe
b4b7a4ef09 Merge branch 'master' into for-linus
Conflicts:
	block/Kconfig

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-03-19 08:05:10 +01:00
Philipp Reisner
309d1608cc drbd: Reduce the time an empty resync takes usually
This mitigates changes introduced with commit:
http://git.drbd.org/?p=drbd-8.3.git;a=commit;h=4b6803a3276652da3737

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-03-11 16:09:03 +01:00
Lars Ellenberg
c42b6cf4b3 drbd: add missing drbd command names to avoid <NULL> in error messages
cmdname() should map command number to its human readable
representation. The string table was incomplete, though.

Maybe rather do a switch() block, and let the compiler help us
to keep it complete?

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-03-11 16:04:05 +01:00
Philipp Reisner
cf14c2e987 drbd: --dry-run option for drbdsetup net ( drbdadm -- --dry-run connect <res> )
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-03-11 15:51:23 +01:00
Daniel Mack
3ad2f3fbb9 tree-wide: Assorted spelling fixes
In particular, several occurances of funny versions of 'success',
'unknown', 'therefore', 'acknowledge', 'argument', 'achieve', 'address',
'beginning', 'desirable', 'separate' and 'necessary' are fixed.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Joe Perches <joe@perches.com>
Cc: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-02-09 11:13:56 +01:00
Philipp Reisner
a393db6f10 drbd: Allow online resizing of DRBD devices while peer not reachable (needs to be explicitly forced)
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2010-01-12 10:02:46 +01:00
Lars Ellenberg
36bfc7e210 drbd: check on CONFIG_LBDAF, not LBD
It is called LBDAF since 2.6.31.

impact:
without this change, on 32bit,
DRBD would wrongly claim to only support 2TiB devices.

Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
2010-01-07 14:07:11 +01:00
Emese Revfy
7d4e9d0962 drbd: Constify struct file_operations
Signed-off-by: Emese Revfy <re.emese@gmail.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
2009-12-21 12:45:15 +01:00
Randy Dunlap
132cc538cd drbd: needs __ratelimit()
drbd_int.h uses __ratelimit(), so it needs to #include ratelimit.h:

drivers/block/drbd/drbd_int.h:1765: error: implicit declaration of function '__ratelimit'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: drbd-dev@lists.linbit.com
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-10-07 19:26:00 +02:00
Jens Axboe
6a0afdf58d drbd: remove tracing bits
They should be reimplemented in the current scheme.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-10-01 21:17:58 +02:00
Philipp Reisner
b411b3637f The DRBD driver
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2009-10-01 21:17:49 +02:00