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path: root/drivers/lightnvm/pblk.h
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2018-07-13lightnvm: pblk: add asynchronous partial readHeiner Litz
In the read path, partial reads are currently performed synchronously which affects performance for workloads that generate many partial reads. This patch adds an asynchronous partial read path as well as the required partial read ctx. Signed-off-by: Heiner Litz <hlitz@ucsc.edu> Reviewed-by: Igor Konopko <igor.j.konopko@intel.com> Signed-off-by: Matias Bjørling <mb@lightnvm.io> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-13lightnvm: pblk: expose generic disk name on pr_* msgsMatias Bjørling
The error messages in pblk does not say which pblk instance that a message occurred from. Update each error message to reflect the instance it belongs to, and also prefix it with pblk, so we know the message comes from the pblk module. Signed-off-by: Matias Bjørling <mb@lightnvm.io> Reviewed-by: Javier González <javier@cnexlabs.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-13lightnvm: move NVM_DEBUG to pblkMatias Bjørling
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>
2018-07-13lightnvm: pblk: handle case when mw_cunits equals to 0Marcin Dziegielewski
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>
2018-06-01lightnvm: pblk: kick writer on new flush pointsHans Holmberg
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>
2018-06-01lightnvm: pblk: garbage collect lines with failed writesHans Holmberg
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>
2018-06-01lightnvm: pblk: rework write error recovery pathHans Holmberg
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>
2018-06-01lightnvm: pblk: remove dead functionJavier González
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>
2018-06-01lightnvm: pass flag on graceful teardown to targetsJavier González
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>
2018-06-01lightnvm: pblk: remove unnecessary argumentJavier González
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>
2018-05-30lightnvm: convert to bioset_init()/mempool_init()Kent Overstreet
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>
2018-03-29lightnvm: pblk: implement 2.0 supportJavier González
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>
2018-03-29lightnvm: pblk: implement get log report chunkJavier González
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>
2018-03-29lightnvm: pblk: rename ppaf* to addrf*Javier González
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>
2018-03-29lightnvm: add support for 2.0 address formatJavier González
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>
2018-03-29lightnvm: normalize geometry nomenclatureJavier González
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>
2018-03-29lightnvm: simplify geometry structureJavier González
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>
2018-03-29lightnvm: pblk: refactor bad block identificationJavier González
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>
2018-03-29lightnvm: pblk: add padding distribution sysfs attributeHans Holmberg
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>
2018-03-29lightnvm: pblk: export write amplification counters to sysfsHans Holmberg
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>
2018-03-29lightnvm: pblk: check data lines version on recoveryHans Holmberg
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>
2018-01-05lightnvm: pblk: refactor pblk_ppa_comp functionMatias Bjørling
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>
2018-01-05lightnvm: pblk: add iostat supportJavier González
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>
2018-01-05lightnvm: pblk: do not log recovery read errorsJavier González
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>
2018-01-05lightnvm: set target over-provision on create ioctlJavier González
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>
2018-01-05lightnvm: pblk: use exact free block counter in RLJavier González
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>
2018-01-05lightnvm: pblk: rename sync_point to flush_pointHans Holmberg
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>
2018-01-05lightnvm: pblk: refactor emeta consistency checkHans Holmberg
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>
2018-01-05lightnvm: pblk: remove pblk_for_each_lun helperJavier González
Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-05lightnvm: pblk: compress and reorder helper functionsJavier González
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>
2018-01-05lightnvm: make geometry structures 2.0 readyMatias Bjørling
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>
2017-11-21lightnvm: Convert timers to use timer_setup()Kees Cook
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>
2017-10-24lightnvm: pblk: remove leftover testing functionJavier González
A previous patch inadvertently left an unused test function in the header, kill it. Fixes: 8bd400204bd5 ("lightnvm: pblk: cleanup unused and static functions") Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-13lightnvm: implement generic path for sync I/OJavier González
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>
2017-10-13lightnvm: pblk: cleanup unused and static functionsJavier González
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>
2017-10-13lightnvm: pblk: gc all lines in the pipeline before exitHans Holmberg
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>
2017-10-13lightnvm: pblk: start gc if needed during initHans Holmberg
Start GC if needed, directly after init, as we might need to garbage collect in order to make room for user writes. Create a helper function that allows to kick GC without exposing the internals of the GC/rate-limiter interaction. 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>
2017-10-13lightnvm: pblk: free full lines during recoveryHans Holmberg
When rebuilding the L2P table, any full lines (lines without any valid sectors) will be identified. If these lines are not freed, we risk not being able to allocate the first data line. This patch refactors the part of GC that frees empty lines into a separate function and adds a call to this after the L2P table has been rebuilt. 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>
2017-10-13lightnvm: pblk: enable 1 LUN configurationJavier González
Metadata I/Os are scheduled to minimize their impact on user data I/Os. When there are enough LUNs instantiated (i.e., enough bandwidth), it is easy to interleave metadata and data one after the other so that metadata I/Os are the ones being blocked and not vice-versa. We do this by calculating the distance between the I/Os in terms of the LUNs that are not in used, and selecting a free LUN that satisfies a the simple heuristic that metadata is scheduled behind. The per-LUN semaphores guarantee consistency. This works fine on >1 LUN configuration. However, when a single LUN is instantiated, this design leads to a deadlock, where metadata waits to be scheduled on a free LUN. This patch implements the 1 LUN case by simply scheduling the metadada I/O after the data I/O. In the process, we refactor the way a line is replaced to ensure that metadata writes are submitted after data writes in order to guarantee block sequentiality. Note that, since there is only one LUN, both I/Os will block each other by design. However, such configuration only pursues tight read latencies, not write bandwidth. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-13lightnvm: pblk: guarantee line integrity on readsJavier González
When a line is recycled during garbage collection, reads can still be issued to the line. If the line is freed in the middle of this process, data corruption might occur. This patch guarantees that lines are not freed in the middle of reads that target them (lines). Specifically, we use the existing line reference to decide when a line is eligible for being freed after the recycle process. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-13lightnvm: pblk: check lba sanity on read pathJavier González
As part of pblk's recovery scheme, we store the lba mapped to each physical sector on the device's out-of-bound (OOB) area. On the read path, we can use this information to validate that the data being delivered to the upper layers corresponds to the lba being requested. The cost of this check is an extra copy on the DMA region on the device and an extra comparison in the host, given that (i) the OOB area is being read together with the data in the media, and (ii) the DMA region allocated for the ppa list can be reused for the metadata stored on the OOB area. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-13lightnvm: pblk: refactor rqd alloc/freeJavier González
Refactor the rqd allocation and free functions so that all I/O types can use these helper functions. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-13lightnvm: pblk: improve naming for internal req.Javier González
Each request type sent to the LightNVM subsystem requires different metadata. Until now, we have tailored this metadata based on write, read and erase commands. However, pblk uses different metadata for internal writes that do not hit the write buffer. Instead of abusing the metadata for reads, create a new request type - internal write to improve code readability. In the process, create internal values for each I/O type instead of abusing the READ/WRITE macros, as suggested by Christoph. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-13lightnvm: pblk: allocate bio size more accuratelyJavier González
Wait until we know the exact number of ppas to be sent to the device, before allocating the bio. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-13lightnvm: pblk: simplify data validity check on GCJavier González
When a line is selected for recycling by the garbage collector (GC), the line state changes and the invalid bitmap is frozen, preventing invalidations from happening. Throughout the GC, the L2P map is checked to verify that not data being recycled has been updated. The last check is done before the new map is being stored on the L2P table. Though this algorithm works, it requires a number of corner cases to be checked each time the L2P table is being updated. This complicates readability and is error prone in case that the recycling algorithm is modified. Instead, this patch makes the invalid bitmap accessible even when the line is being recycled. When recycled data is being remapped, it is enough to check the invalid bitmap for the line before updating the L2P table. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-13lightnvm: pblk: use constant for GC max inflightJavier González
Use a constant to set the maximum number of inflight GC requests allowed. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-13lightnvm: pblk: do not use a mempool for line bitmapsJavier González
pblk holds two sector bitmaps: one to keep track of the mapped sectors while the line is active and another one to keep track of the invalid sectors. The latter is kept during the whole live of the line, until it is recycled. Since we cannot guarantee forward progress for the mempool in this case, get rid of the mempool and simply allocate memory through kmalloc. Reported-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-13lightnvm: pblk: decouple read/erase mempoolsJavier González
Since read and erase paths offer different guarantees for inflight I/Os, separate the mempools to set the right min_nr for each on creation. Reported-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-13lightnvm: pblk: simplify work_queue mempoolJavier González
In pblk, we have a mempool to allocate a generic structure that we pass along workqueues. This is heavily used in the GC path in order to have enough inflight reads and fully utilize the GC bandwidth. However, the current GC path copies data to the host memory and puts it back into the write buffer. This requires a vmalloc allocation for the data and a memory copy. Thus, guaranteeing the allocation by using a mempool for the structure in itself does not give us much. Until we implement support for vector copy to avoid moving data through the host, just allocate the workqueue structure using kmalloc. This allows us to have a much smaller mempool. Reported-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-13lightnvm: pblk: fix min size for page mempoolJavier González
pblk uses an internal page mempool for allocating pages on internal bios. The main two users of this memory pool are partial reads (reads with some sectors in cache and some on media) and padded writes, which need to add dummy pages to an existing bio already containing valid data (and with a large enough bioset allocated). In both cases, the maximum number of pages per bio is defined by the maximum number of physical sectors supported by the underlying device. This patch fixes a bad mempool allocation, where the min_nr of elements on the pool was fixed (to 16), which is lower than the maximum number of sectors supported by NVMe (as of the time for this patch). Instead, use the maximum number of allowed sectors reported by the device. Reported-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>