When recovering a line, an extra check was added when debugging was
active, such that minor version where also checked. Unfortunately,
this used the ifdef NVM_DEBUG, which is not correct.
Instead use the proper DEBUG def, and now that it compiles, also fix
the variable.
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Fixes: d0ab0b1ab9 ("lightnvm: pblk: check data lines version on recovery")
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There is no users of CONFIG_NVM_DEBUG in the LightNVM subsystem. All
users are in pblk. Rename NVM_DEBUG to NVM_PBLK_DEBUG and enable
only for pblk.
Also fix up the CONFIG_NVM_PBLK entry to follow the code style for
Kconfig files.
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Some devices can expose mw_cunits equal to 0, it can cause the
creation of too small write buffer and cause performance to drop
on write workloads.
Additionally, write buffer size must cover write data requirements,
such as WS_MIN and MW_CUNITS - it must be greater than or equal to
the larger one multiplied by the number of PUs. However, for
performance reasons, use the WS_OPT value to calculation instead of
WS_MIN.
Because the place where buffer size is calculated was changed, this
patch also removes pgs_in_buffer filed in pblk structure.
Signed-off-by: Marcin Dziegielewski <marcin.dziegielewski@intel.com>
Signed-off-by: Igor Konopko <igor.j.konopko@intel.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'for-linus-20180623' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
- Further timeout fixes. We aren't quite there yet, so expect another
round of fixes for that to completely close some of the IRQ vs
completion races. (Christoph/Bart)
- Set of NVMe fixes from the usual suspects, mostly error handling
- Two off-by-one fixes (Dan)
- Another bdi race fix (Jan)
- Fix nbd reconfigure with NBD_DISCONNECT_ON_CLOSE (Doron)
* tag 'for-linus-20180623' of git://git.kernel.dk/linux-block:
blk-mq: Fix timeout handling in case the timeout handler returns BLK_EH_DONE
bdi: Fix another oops in wb_workfn()
lightnvm: Remove depends on HAS_DMA in case of platform dependency
nvme-pci: limit max IO size and segments to avoid high order allocations
nvme-pci: move nvme_kill_queues to nvme_remove_dead_ctrl
nvme-fc: release io queues to allow fast fail
nbd: Add the nbd NBD_DISCONNECT_ON_CLOSE config flag.
block: sed-opal: Fix a couple off by one bugs
blk-mq-debugfs: Off by one in blk_mq_rq_state_name()
nvmet: reset keep alive timer in controller enable
nvme-rdma: don't override opts->queue_size
nvme-rdma: Fix command completion race at error recovery
nvme-rdma: fix possible free of a non-allocated async event buffer
nvme-rdma: fix possible double free condition when failing to create a controller
Revert "block: Add warning for bi_next not NULL in bio_endio()"
block: fix timeout changes for legacy request drivers
Remove dependencies on HAS_DMA where a Kconfig symbol depends on another
symbol that implies HAS_DMA, and, optionally, on "|| COMPILE_TEST".
In most cases this other symbol is an architecture or platform specific
symbol, or PCI.
Generic symbols and drivers without platform dependencies keep their
dependencies on HAS_DMA, to prevent compiling subsystems or drivers that
cannot work anyway.
This simplifies the dependencies, and allows to improve compile-testing.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
As we move stuff around, some doc references are broken. Fix some of
them via this script:
./scripts/documentation-file-ref-check --fix
Manually checked if the produced result is valid, removing a few
false-positives.
Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Currently the error exit path when the emeta could not be
interpreted is via fail_free_ws and this fails to free
invalid_bitmap. Fix this by adding another exit label and
exiting via this to kfree invalid_bitmap.
Detected by CoverityScan, CID#1469659 ("Resource leak")
Fixes: 48b8d20895 ("lightnvm: pblk: garbage collect lines with failed writes")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Fixes the following sparse warning:
drivers/lightnvm/pblk-init.c:23:14: warning:
symbol 'write_buffer_size' was not declared. Should it be static?
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
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>
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: 32ef9412c1 ("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>
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>
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>
Convert lightnvm to embedded bio sets.
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Smatch complains that flush_workqueue() dereferences the work queue
pointer but then we check if it's NULL on the next line when it's too
late. These NULL checks can be removed because the module won't load if
we can't allocate the work queues.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If the line has not been written to, we should not
try to recover any data from it, so check the state of the
chunks in the line before attempting to read smeta.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Implement 2.0 support in pblk. This includes the address formatting and
mapping paths, as well as the sysfs entries for them.
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 preparation of pblk supporting 2.0, implement the get log report
chunk in pblk. Also, define the chunk states as given in the 2.0 spec.
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 preparation for 2.0 support in pblk, rename variables referring to
the address format to addrf and reserve ppaf for the 1.2 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>
At this point, only 1.2 spec is supported, thus check for it. Also,
since device-side L2P is only supported in the 1.2 spec, make sure to
only check its value under 1.2.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The 2.0 spec provides a report chunk log page that can be retrieved
using the stangard nvme get log page. This replaces the dedicated
get/put bad block table in 1.2.
This patch implements the helper functions to allow targets retrieve the
chunk metadata using get log page. It makes nvme_get_log_ext available
outside of nvme core so that we can use it form lightnvm.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
On address conversions, use the generic device, instead of the target
device. This allows to use conversions outside of the target's realm.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add support for 2.0 address format. Also, align address bits for 1.2 and
2.0 to be able to operate on channel and luns without requiring a format
conversion. Use a generic address format for this purpose.
Also, convert the generic operations to the generic format in pblk.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Normalize nomenclature for naming channels, luns, chunks, planes and
sectors as well as derivations in order to improve readability.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Separate the version between major and minor on the generic geometry and
represent it through sysfs in the 2.0 path. The 1.2 path only shows the
major version to preserve the existing user space interface.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, the device geometry is stored redundantly in the nvm_id and
nvm_geo structures at a device level. Moreover, when instantiating
targets on a specific number of LUNs, these structures are replicated
and manually modified to fit the instance channel and LUN partitioning.
Instead, create a generic geometry around nvm_geo, which can be used by
(i) the underlying device to describe the geometry of the whole device,
and (ii) instances to describe their geometry independently.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently all functions for handling the lightnvm core ioctl commands
do a check for CAP_SYS_ADMIN.
Change this to fail early in nvm_ctl_ioctl(), so we don't have to
duplicate the permission checks all over.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
fix reading bad block device information to correctly setup the per line
blk_bitmap during lightnvm initialization
Signed-off-by: Heiner Litz <hlitz@ucsc.edu>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The nvme driver sets up the size of the nvme namespace in two steps.
First it initializes the device with standard logical block and
metadata sizes, and then sets the correct logical block and metadata
size. Due to the OCSSD 2.0 specification relies on the namespace to
expose these sizes for correct initialization, let it be updated
appropriately on the LightNVM side as well.
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The value of max_phys_sect is always static. Instead of
defining it in the nvm_dev_ops structure, declare it as a global
value.
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Implement the geometry data structures for 2.0 and enable a drive
to be identified as one, including exposing the appropriate 2.0
sysfs entries.
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There are no groups in the 2.0 specification, make sure that the
nvm_id structure is flattened before 2.0 data structures are added.
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In preparation for the OCSSD 2.0 spec. bad block identification,
refactor the current code to generalize bad block get/set functions and
structures.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Make sure that we are not advancing the sync pointer while
we're adding bios to the write buffer entry completion list.
This race condition results in bios not completing and was identified
by a hang when running xfstest generic/113.
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>
When shutting down pblk the write buffer is flushed and if the
current line can't fit the data in the write buffer we need
to allocate a new line, so remove the check that prevents this.
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>
Unless we delete the timer that wakes up the write thread
before we stop the thread we risk re-starting the thread, so
delete the timer first.
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>
When pblk receives a sync, all data up to that point in the write buffer
must be comitted to persistent storage, and as flash memory comes with a
minimal write size there is a significant cost involved both in terms
of time for completing the sync and in terms of write amplification
padded sectors for filling up to the minimal write size.
In order to get a better understanding of the costs involved for syncs,
Add a sysfs attribute to pblk: padded_dist, showing a normalized
distribution of sectors padded. In order to facilitate measurements of
specific workloads during the lifetime of the pblk instance, the
distribution can be reset by writing 0 to the attribute.
Do this by introducing counters for each possible padding:
{0..(minimal write size - 1)} and calculate the normalized distribution
when showing the attribute.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Javier González <javier@cnexlabs.com>
Rearranged total_buckets statement in pblk_sysfs_get_padding_dist
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In a SSD, write amplification, WA, is defined as the average
number of page writes per user page write. Write amplification
negatively affects write performance and decreases the lifetime
of the disk, so it's a useful metric to add to sysfs.
In plkb's case, the number of writes per user sector is the sum of:
(1) number of user writes
(2) number of sectors written by the garbage collector
(3) number of sectors padded (i.e. due to syncs)
This patch adds persistent counters for 1-3 and two sysfs attributes
to export these along with WA calculated with five decimals:
write_amp_mileage: the accumulated write amplification stats
for the lifetime of the pblk instance
write_amp_trip: resetable stats to facilitate delta measurements,
values reset at creation and if 0 is written
to the attribute.
64-bit counters are used as a 32 bit counter would wrap around
already after about 17 TB worth of user data. It will take a
long long time before the 64 bit sector counters wrap around.
The counters are stored after the bad block bitmap in the first
emeta sector of each written line. There is plenty of space in the
first emeta sector, so we don't need to bump the major version of
the line data format.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
As a preparation for future bumps of data line persistent storage
versions, we need to start checking the emeta line version during
recovery. Also slit up the current emeta/smeta version into two
bytes (major,minor).
Recovering lines with the same major number as the current pblk data
line version must succeed. This means that any changes in the
persistent format must be:
(1) Backward compatible: if we switch back to and older
kernel, recovery of lines stored with major == current_major
and minor > current_minor must succeed.
(2) Forward compatible: switching to a newer kernel,
recovery of lines stored with major=current_major and
minor < minor must handle the data format differences
gracefully(i.e. initialize new data structures to default values).
If we detect lines that have a different major number than
the current we must abort recovery. The user must manually
migrate the data in this case.
Previously the version stored in the emeta header was copied
from smeta, which has version 1, so we need to set the minor
version to 1.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
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 check if there are bad sectors in the entire emeta-area
we risk ending up with valid bitmap / available sector count inconsistency.
This results in lines with a bad chunk at the last LUN marked as bad,
so go through the whole emeta area and mark up the invalid sectors.
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>
Omit an extra message for a memory allocation failure in this function.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch has been generated as follows:
for verb in set_unlocked clear_unlocked set clear; do
replace-in-files queue_flag_${verb} blk_queue_flag_${verb%_unlocked} \
$(git grep -lw queue_flag_${verb} drivers block/bsg*)
done
Except for protecting all queue flag changes with the queue lock
this patch does not change any functionality.
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch does not change any functionality.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Shorten function to simply return the value of the if statement.
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since pblk registers its own block device, the iostat accounting is
not automatically done for us. Therefore, add the necessary
accounting logic to satisfy the iostat interface.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add the instance name to the information printed out on target creation.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Refactor the way we free the write buffer to ensure that all entries get
freed in case of an error on the init sequence.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When creating the write thread, ensure that the kthread has been created
before initializing the timer responsible from kicking it. Otherwise, if
the kthread creation fails or gets killed from used space, we risk
kicking an empty thread structure.
Also, since the kthread creation can be interrupted form user space,
adapt the error path to not report an error when this happens, since it
is intentional that the instance creation is aborted.
Signed-off-by: Javier González <javier@cnexlabs.com>
Updated source to reflect the new timer_setup API.
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
On scan recovery, reads can fail. This happens because the first page
for each line is read in order to determined if the line has been used
(and thus needs to be recovered), or not. This can lead to "empty page"
read errors.
Since these errors are normal, do not log them, as they are confusing
when reviewing the logs.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
On recovery, do not stop L2P recovery if reads report high ECC error
as the data is still available.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Allow to set the over-provision percentage on target creation. In case
that the value is not provided, fall back to the default value set by
the target.
In pblk, set the default OP to 11% of the total size of the device
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Until now, pblk's rate-limiter has used a heuristic to reserve space for
GC I/O given that the over-provision area was fixed.
In preparation for allowing to define the over-provision area on target
creation, define a dedicated free_block counter in the rate-limiter to
track the number of blocks being used for user data.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
pblk_gc_stop just sets pblk->gc->gc_active to zero, ignoring
the flush parameter. This is plain confusing, so remove the
function and set the gc active flag at the call points instead.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Unless we protect flush pointer updates with a lock, we risk
resetting new flush points before we've synced all sectors
up to that point.
This patch protects new flush points with the same spin lock
that is being held when advancing the sync pointer and
resetting completed flush points.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move completion of syncs and clearing of flush points to the
write completion path - this ensures that the data has been
comitted to the media before completing bios containing syncs.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Sync point is a really confusing name for keeping track of
the last entry that needs to be flushed so change the name
to to flush_point instead.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently pblk_recov_get_lba list does two separate things:
it checks the consistency of the emeta and extracts the lba list.
This patch separates the consistency check to make the code easier
to read and to prepare for version checks of the line emeta
persistent data format version.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Through time, we have generated some redundant helper functions.
Refactor them to eliminate redundant and unnecessary code. Also, reorder
them to improve readability
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Until now, target unique naming is only guaranteed per device. This is
ok from a lightnvm perspective, but not from a sysfs one, since groups
will collide regardless of the underlying device.
Check that names are unique across all lightnvm-capable devices.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Refactor target type lookup to use/not use locks explicitly instead of
using a hidden parameter to make the function locking.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Prepare for the 2.0 revision by adapting the geometry
structures to coexist with the 1.2 revision.
Signed-off-by: Matias Bjørling <m@bjorling.me>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The lower page table is unused. All page tables reported by 1.2
devices are all reporting a sequential 1:1 page mapping. This is
also not used going forward with the 2.0 revision.
Signed-off-by: Matias Bjørling <m@bjorling.me>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that rrpc have been removed. Also remove the hybrid 1.2 support
from the core.
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that rrpc has been removed, the only users of the ppa helpers
is pblk. However, pblk already defines similar functions.
Switch pblk to use the internal ones, and remove the generic ppa
helpers.
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The hybrid mode for 1.2 revision was deprecated, and have
no users. Remove to make it easier to move to the 2.0 revision.
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.
Cc: Matias Bjorling <mb@lightnvm.io>
Cc: linux-block@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Pull core block layer updates from Jens Axboe:
"This is the main pull request for block storage for 4.15-rc1.
Nothing out of the ordinary in here, and no API changes or anything
like that. Just various new features for drivers, core changes, etc.
In particular, this pull request contains:
- A patch series from Bart, closing the whole on blk/scsi-mq queue
quescing.
- A series from Christoph, building towards hidden gendisks (for
multipath) and ability to move bio chains around.
- NVMe
- Support for native multipath for NVMe (Christoph).
- Userspace notifications for AENs (Keith).
- Command side-effects support (Keith).
- SGL support (Chaitanya Kulkarni)
- FC fixes and improvements (James Smart)
- Lots of fixes and tweaks (Various)
- bcache
- New maintainer (Michael Lyle)
- Writeback control improvements (Michael)
- Various fixes (Coly, Elena, Eric, Liang, et al)
- lightnvm updates, mostly centered around the pblk interface
(Javier, Hans, and Rakesh).
- Removal of unused bio/bvec kmap atomic interfaces (me, Christoph)
- Writeback series that fix the much discussed hundreds of millions
of sync-all units. This goes all the way, as discussed previously
(me).
- Fix for missing wakeup on writeback timer adjustments (Yafang
Shao).
- Fix laptop mode on blk-mq (me).
- {mq,name} tupple lookup for IO schedulers, allowing us to have
alias names. This means you can use 'deadline' on both !mq and on
mq (where it's called mq-deadline). (me).
- blktrace race fix, oopsing on sg load (me).
- blk-mq optimizations (me).
- Obscure waitqueue race fix for kyber (Omar).
- NBD fixes (Josef).
- Disable writeback throttling by default on bfq, like we do on cfq
(Luca Miccio).
- Series from Ming that enable us to treat flush requests on blk-mq
like any other request. This is a really nice cleanup.
- Series from Ming that improves merging on blk-mq with schedulers,
getting us closer to flipping the switch on scsi-mq again.
- BFQ updates (Paolo).
- blk-mq atomic flags memory ordering fixes (Peter Z).
- Loop cgroup support (Shaohua).
- Lots of minor fixes from lots of different folks, both for core and
driver code"
* 'for-4.15/block' of git://git.kernel.dk/linux-block: (294 commits)
nvme: fix visibility of "uuid" ns attribute
blk-mq: fixup some comment typos and lengths
ide: ide-atapi: fix compile error with defining macro DEBUG
blk-mq: improve tag waiting setup for non-shared tags
brd: remove unused brd_mutex
blk-mq: only run the hardware queue if IO is pending
block: avoid null pointer dereference on null disk
fs: guard_bio_eod() needs to consider partitions
xtensa/simdisk: fix compile error
nvme: expose subsys attribute to sysfs
nvme: create 'slaves' and 'holders' entries for hidden controllers
block: create 'slaves' and 'holders' entries for hidden gendisks
nvme: also expose the namespace identification sysfs files for mpath nodes
nvme: implement multipath access to nvme subsystems
nvme: track shared namespaces
nvme: introduce a nvme_ns_ids structure
nvme: track subsystems
block, nvme: Introduce blk_mq_req_flags_t
block, scsi: Make SCSI quiesce and resume work reliably
block: Add the QUEUE_FLAG_PREEMPT_ONLY request queue flag
...
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A previous patch inadvertently left an unused test function in the
header, kill it.
Fixes: 8bd400204b ("lightnvm: pblk: cleanup unused and static functions")
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Christoph correctly points out that this issue is no different
for other block devices, and poking at cross layer internals
is not the right way to solve it.
This reverts commit bb6aa6f082.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Implement a generic path for sending sync I/O on LightNVM. This allows
to reuse the standard synchronous path trough blk_execute_rq(), instead
of implementing a wait_for_completion on the target side (e.g., pblk).
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The amount of GC I/O on the write buffer is managed by the rate-limiter,
which is calculated as a function of the number of available free
blocks. When reaching the stable point, we risk having scheduled more
I/Os for GC than are allowed on the write buffer. This would result on
the GC semaphore balancing the outstanding read GC I/Os to be reported
as "hung", though the behavior is normal.
Solve this by allowing to schedule when we detect that the read GC path
is not moving forward.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Cleanup up unused and static functions across the whole codebase.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Lockdep complains about being in atomic context while freeing line
metadata - and rightly so as we take a spinlock and end up calling
vfree that might sleep(in pblk_mfree).
There is no need for holding the line manager free_lock while
freeing line metadata as the pipeline as stopped, so remove the lock.
Fixes: 588726d3ec ("lightnvm: pblk: fail gracefully on irrec. error")
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
During garbage collect, lbas being written can end up
being invalidated. Make sure that this is reflected in
the valid lba count.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Finish garbage collect of the lines that are in the gc pipeline
before exiting. Ensure that all lines already in in the pipeline
goes through, from read to write.
Do this by keeping track of how many lines are in the pipeline
and waiting for that number to reach zero before exiting the gc
reader task.
Since we're adding a new gc line counter, change the name of
inflight_gc to read_inflight_gc to make the distinction clear.
Signed-off-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
