linux-toradex.git/drivers/block/drbd/drbd_worker.c, branch v4.9.3

block: rename bio bi_rw to bi_opf

2016-08-07T20:41:02+00:00

Since commit 63a4cc24867d, bio->bi_rw contains flags in the lower
portion and the op code in the higher portions. This means that
old code that relies on manually setting bi_rw is most likely
going to be broken. Instead of letting that brokeness linger,
rename the member, to force old and out-of-tree code to break
at compile time instead of at runtime.

No intended functional changes in this commit.

Signed-off-by: Jens Axboe

block: get rid of bio_rw and READA

2016-07-20T23:37:01+00:00

These two are confusing leftover of the old world order, combining
values of the REQ_OP_ and REQ_ namespaces.  For callers that don't
special case we mostly just replace bi_rw with bio_data_dir or
op_is_write, except for the few cases where a switch over the REQ_OP_
values makes more sense.  Any check for READA is replaced with an
explicit check for REQ_RAHEAD.  Also remove the READA alias for
REQ_RAHEAD.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Johannes Thumshirn 
Reviewed-by: Mike Christie 
Signed-off-by: Jens Axboe

drbd: code cleanups without semantic changes

2016-06-14T03:43:07+00:00

This contains various cosmetic fixes ranging from simple typos to
const-ifying, and using booleans properly.

Original commit messages from Fabian's patch set:
drbd: debugfs: constify drbd_version_fops
drbd: use seq_put instead of seq_print where possible
drbd: include linux/uaccess.h instead of asm/uaccess.h
drbd: use const char * const for drbd strings
drbd: kerneldoc warning fix in w_e_end_data_req()
drbd: use unsigned for one bit fields
drbd: use bool for peer is_ states
drbd: fix typo
drbd: use | for bitmask combination
drbd: use true/false for bool
drbd: fix drbd_bm_init() comments
drbd: introduce peer state union
drbd: fix maybe_pull_ahead() locking comments
drbd: use bool for growing
drbd: remove redundant declarations
drbd: replace if/BUG by BUG_ON

Signed-off-by: Fabian Frederick 
Signed-off-by: Roland Kammerer 
Signed-off-by: Jens Axboe

drbd: introduce WRITE_SAME support

2016-06-14T03:43:07+00:00

We will support WRITE_SAME, if
 * all peers support WRITE_SAME (both in kernel and DRBD version),
 * all peer devices support WRITE_SAME
 * logical_block_size is identical on all peers.

We may at some point introduce a fallback on the receiving side
for devices/kernels that do not support WRITE_SAME,
by open-coding a submit loop. But not yet.

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

drbd: introduce unfence-peer handler

2016-06-14T03:43:06+00:00

When resync is finished, we already call the "after-resync-target"
handler (on the former sync target, obviously), once per volume.

Paired with the before-resync-target handler, you can create snapshots,
before the resync causes the volumes to become inconsistent,
and discard those snapshots again, once they are no longer needed.

It was also overloaded to be paired with the "fence-peer" handler,
to "unfence" once the volumes are up-to-date and known good.

This has some disadvantages, though: we call "fence-peer" for the whole
connection (once for the group of volumes), but would call unfence as
side-effect of after-resync-target once for each volume.

Also, we fence on a (current, or about to become) Primary,
which will later become the sync-source.

Calling unfence only as a side effect of the after-resync-target
handler opens a race window, between a new fence on the Primary
(SyncTarget) and the unfence on the SyncTarget, which is difficult to
close without some kind of "cluster wide lock" in those handlers.

We would not need those handlers if we could still communicate.
Which makes trying to aquire a cluster wide lock from those handlers
seem like a very bad idea.

This introduces the "unfence-peer" handler, which will be called
per connection (once for the group of volumes), just like the fence
handler, only once all volumes are back in sync, and on the SyncSource.

Which is expected to be the node that previously called "fence", the
node that is currently allowed to be Primary, and thus the only node
that could trigger a new "fence" that could race with this unfence.

Which makes us not need any cluster wide synchronization here,
serializing two scripts running on the same node is trivial.

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

drbd: Create the protocol feature THIN_RESYNC

2016-06-14T03:43:04+00:00

If thinly provisioned volumes are used, during a resync the sync source
tries to find out if a block is deallocated. If it is deallocated, then
the resync target uses block_dev_issue_zeroout() on the range in
question.

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

drbd: Implement handling of thinly provisioned storage on resync target nodes

2016-06-14T03:43:04+00:00

If during resync we read only zeroes for a range of sectors assume
that these secotors can be discarded on the sync target node.

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

drbd: use bio op accessors

2016-06-07T19:41:38+00:00

Separate the op from the rq_flag_bits and have drbd
set/get the bio using bio_set_op_attrs/bio_op.

Signed-off-by: Mike Christie 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Jens Axboe

drbd: Use shash and ahash

2016-01-27T12:36:08+00:00

This patch replaces uses of the long obsolete hash interface with
either shash (for non-SG users) or ahash.

Signed-off-by: Herbert Xu

drbd: make drbd known to lsblk: use bd_link_disk_holder

2015-11-25T16:22:02+00:00

lsblk should be able to pick up stacking device driver relations
involving DRBD conveniently.

Even though upstream kernel since 2011 says
	"DON'T USE THIS UNLESS YOU'RE ALREADY USING IT."
a new user has been added since (bcache),
which sets the precedences for us to use it as well.

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