linux.git/drivers/block/drbd/drbd_actlog.c, branch v3.8

drbd: don't try to clear bits once the disk has failed

2012-11-09T13:11:42+00:00

If the disk has failed already, there is no point trying to change the
bitmap. drbd_set_out_of_sync() already had this safeguard,
time to add it to drbd_set_in_sync() as well.

This also prevents some warning messages, like
 FIXME asender in bm_change_bits_to, bitmap locked for 'detach' by worker
if our disk fails during resync, while there are some resync acks queued up.

Signed-off-by: Philipp Reisner 
Signed-off-by: Lars Ellenberg

drbd: wait for meta data IO completion even with failed disk, unless force-detached

2012-11-09T13:11:40+00:00

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 
Signed-off-by: Lars Ellenberg

drbd: announce FLUSH/FUA capability to upper layers

2012-11-09T13:05:44+00:00

In 8.4, we may have bios spanning two activity log extents.
Fixup drbd_al_begin_io() and drbd_al_complete_io() to deal with zero sized bios.

Signed-off-by: Philipp Reisner 
Signed-off-by: Lars Ellenberg

drbd: differentiate between normal and forced detach

2012-11-08T15:58:39+00:00

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 
Signed-off-by: Lars Ellenberg

drbd: move the drbd_work_queue from drbd_socket to drbd_connection

2012-11-08T15:58:34+00:00

cherry-picked and adapted from drbd 9 devel branch
In 8.4, we don't distinguish between "resource work" and "connection
work" yet, we have one worker for both, as we still have only one connection.

We only ever used the "data.work",
no need to keep the "meta.work" around.

Move tconn->data.work to tconn->sender_work.

Signed-off-by: Philipp Reisner 
Signed-off-by: Lars Ellenberg

drbd: New disk option al-updates

2012-11-08T15:58:31+00:00

By disabling al-updates one might increase performace. The price for
that is that in case a crashed primary (that had al-updates disabled)
is reintegraded, it will receive a full-resync instead of a bitmap
based resync.

Signed-off-by: Philipp Reisner 
Signed-off-by: Lars Ellenberg

drbd: missing wakeup after drbd_rs_del_all

2012-11-08T15:58:19+00:00

Signed-off-by: Philipp Reisner 
Signed-off-by: Lars Ellenberg

drbd: Consider the disk-timeout also for meta-data IO operations

2012-11-08T15:58:15+00:00

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 
Signed-off-by: Lars Ellenberg

drbd: fix potential spinlock deadlock

2012-11-08T15:58:09+00:00

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 
Signed-off-by: Lars Ellenberg

drbd: Silenced compiler warnings

2012-11-08T15:58:05+00:00

Since version 4.6.1 gcc warns about variables that get
a value assigned, but which are never read later on.

Signed-off-by: Philipp Reisner 
Signed-off-by: Lars Ellenberg