If we end up splitting a bio and the queue goes away between
the initial submission and the later split submission, then we
can block forever in blk_queue_enter() waiting for the reference
to drop to zero. This will never happen, since we already hold
a reference.

Mark a split bio as already having entered the queue, so we can
just use the live non-blocking queue enter variant.

Thanks to Tetsuo Handa for the analysis.

Reported-by: syzbot+c4f9cebf9d651f6e54de@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The counter for the number of allocated pages includes pages in the
mempool's reserve, so checking that the number of allocated pages is 0
needs to happen after we exit the mempool.

Fixes: 6f1c819c ("dm: convert to bioset_init()/mempool_init()")
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Reported-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Mike Snitzer <snitzer@redhat.com>

Fixed to always just use percpu_counter_sum()
Signed-off-by: Jens Axboe <axboe@kernel.dk>

pblk allocates line bitmaps within the line lock unnecessarily. In order
to take pressure out of the fast patch, allocate line bitmaps outside
of this lock and refactor accordingly.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Unless we kick the writer directly when setting a new flush point, the
user risks having to wait for up to one second (the default timeout for
the write thread to be kicked) for the IO to complete.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

When switching between different lun configurations, there is no
guarantee that all lines that contain closed/open chunks have some
valid data to recover.

Check that the smeta chunk has been written to instead. Also
skip bad lines (that does not have enough good chunks).
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

In the read path, pblk gets a reference to the incoming bio and puts it
after ending the bio. Though this behavior is correct, it is unnecessary
since pblk is the one putting the bio, therefore, it cannot disappear
underneath it.

Removing this reference, allows to clean up rqd->bio and avoids pointer
bouncing for the different read paths. Now, the incoming bio always
resides in the read context and pblk's internal bios (if any) reside in
rqd->bio.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

In some cases, users can want set write buffer size manually, e.g. to
adjust it to specific workload. This patch provides the possibility
to set write buffer size via module parameter feature.
Signed-off-by: Marcin Dziegielewski <marcin.dziegielewski@intel.com>
Signed-off-by: Igor Konopko <igor.j.konopko@intel.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

When error occurs during bio_add_page on partial read path, pblk
tries to free pages twice.
Signed-off-by: Igor Konopko <igor.j.konopko@intel.com>
Signed-off-by: Marcin Dziegielewski <marcin.dziegielewski@intel.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Currently in case of error caused by bio_pc_add_page in
pblk_bio_add_pages two issues occur when calling from
pblk_rb_read_to_bio(). First one is in pblk_bio_free_pages, since we
are trying to free pages not allocated from our mempool. Second one
is the warn from dma_pool_free, that we are trying to free NULL
pointer dma.

This commit fix both issues.
Signed-off-by: Igor Konopko <igor.j.konopko@intel.com>
Signed-off-by: Marcin Dziegielewski <marcin.dziegielewski@intel.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Smeta write errors were previously ignored. Skip these
lines instead and throw them back on the free
list, so the chunks will go through a reset cycle
before we attempt to use the line again.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Write failures should not happen under normal circumstances,
so in order to bring the chunk back into a known state as soon
as possible, evacuate all the valid data out of the line and let the
fw judge if the block can be written to in the next reset cycle.

Do this by introducing a new gc list for lines with failed writes,
and ensure that the rate limiter allocates a small portion of
the write bandwidth to get the job done.

The lba list is saved in memory for use during gc as we
cannot gurantee that the emeta data is readable if a write
error occurred.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The write error recovery path is incomplete, so rework
the write error recovery handling to do resubmits directly
from the write buffer.

When a write error occurs, the remaining sectors in the chunk are
mapped out and invalidated and the request inserted in a resubmit list.

The writer thread checks if there are any requests to resubmit,
scans and invalidates any lbas that have been overwritten by later
writes and resubmits the failed entries.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Remove dead function for manual sync. I/O
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

If the namespace is unregistered before the LightNVM target is removed
(e.g., on hot unplug) it is too late for the target to store any metadata
on the device - any attempt to write to the device will fail. In this
case, pass on a "gracefull teardown" flag to the target to let it know
when this happens.

In the case of pblk, we pad the open line (close all open chunks) to
improve data retention. In the event of an ungraceful shutdown, avoid
this part and just clean up.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Do the check for the chunk state after making sure that the chunk type
is supported.

Fixes: 32ef9412 ("lightnvm: pblk: implement get log report chunk")
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Remove unnecessary argument on pblk_line_free()
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Call nvm_submit_io directly and remove an unnecessary indirection on the
read path.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Return a meaningful error when the sanity vector I/O check fails.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

When cleaning up buffer entries as we wrap up, their state should be
"completed". If any of the entries is in "submitted" state, it means
that something bad has happened. Trigger a warning immediately instead of
waiting for the state flag to eventually be updated, thus hiding the
issue.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

In the event of a mismatch between the read LBA and the metadata pointer
reported by the device, improve the error message to be able to detect
the offending physical address (PPA) mapped to the corrupted LBA.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Check that the lba stored in the LBA metadata is correct in the GC path
too. This requires a new helper function to check random reads in the
vector read.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Bad blocks can grow at runtime. Check that the number of valid blocks in
a line are within the sanity threshold before allocating the line for
new writes.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

In the event of a line failing to allocate, fail gracefully and stop the
pipeline to avoid more write failing in the same place.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull NVMe changes from Christoph:

"Below is another set of NVMe updates for 4.18.  Besides the usual bug
 fixes this includes more feature completness in terms of AEN and log
 page handling on the target."

* 'nvme-4.18' of git://git.infradead.org/nvme:
  nvme: use the changed namespaces list log to clear ns data changed AENs
  nvme: mark nvme_queue_scan static
  nvme: submit AEN event configuration on startup
  nvmet: mask pending AENs
  nvmet: add AEN configuration support
  nvmet: implement the changed namespaces log
  nvmet: split log page implementation
  nvmet: add a new nvmet_zero_sgl helper
  nvme.h: add AEN configuration symbols
  nvme.h: add the changed namespace list log
  nvme.h: untangle AEN notice definitions
  nvmet: fix error return code in nvmet_file_ns_enable()
  nvmet: fix a typo in nvmet_file_ns_enable()
  nvme-fabrics: allow internal passthrough command on deleting controllers
  nvme-loop: add support for multiple ports
  nvme-pci: simplify __nvme_submit_cmd
  nvme-pci: Rate limit the nvme timeout warnings
  nvme: allow duplicate controller if prior controller being deleted

There is almost no shared logic, which leads to a very confusing code
flow.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Both callers take just around so function call, so move it in.
Also remove the now pointless blk_mq_sched_init wrapper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Reported-by: Damien Le Moal <Damien.LeMoal@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

These are only used by the block core.  Also move the declarations to
block/blk.h.
Reported-by: Damien Le Moal <Damien.LeMoal@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

No point in doing this in elevator_init.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Damien Le Moal <Damien.LeMoal@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Per section 5.2 we need to issue the corresponding log page to clear an
AEN, so for a namespace data changed AEN we need to read the changed
namespace list log.  And once we read that log anyway we might as well
use it to optimize the rescan.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

And move it toward the top of the file to avoid a forward declaration.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

We should register for AEN events; some law-abiding targets might
not be sending us AENs otherwise.
Signed-off-by: Hannes Reinecke <hare@suse.com>
[hch: slight cleanups]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

Per section 5.2 of the NVMe 1.3 spec:

  "When the controller posts a completion queue entry for an outstanding
  Asynchronous Event Request command and thus reports an asynchronous
  event, subsequent events of that event type are automatically masked by
  the controller until the host clears that event. An event is cleared by
  reading the log page associated with that event using the Get Log Page
  command (see section 5.14)."
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>

AEN configuration via the 'Get Features' and 'Set Features' admin
command is mandatory, so we should be implemeting handling for it.
Signed-off-by: Hannes Reinecke <hare@suse.com>
[hch: use WRITE_ONCE, check for invalid values]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>

Just keep a per-controller buffer of changed namespaces and copy it out
in the get log page implementation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>

Remove the common code to allocate a buffer and copy it into the SGL.
Instead the two no-op implementations just zero the SGL directly, and
the smart log allocates a buffer on its own.  This prepares for the
more elaborate ANA log page.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

Zeroes the SGL in the payload.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

Signed-off-by: Hannes Reinecke <hare@suse.com>
[hch: split from a larger patch]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>

Stop including the event type in the definitions for the notice type.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>