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path: root/drivers/lightnvm
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2016-03-18lightnvm: add a bitmap of lunsWenwei Tao
Add a bitmap of luns to indicate the status of luns: inuse/available. When create targets do the necessary check to avoid allocating luns that are already allocated. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Freed dev->lun_map if nvm_core_init later failed in the init process. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-18lightnvm: specify target's logical address areaWenwei Tao
We can create more than one target on a lightnvm device by specifying its begin lun and end lun. But only specify the physical address area is not enough, we need to get the corresponding non- intersection logical address area division from the backend device's logcial address space. Otherwise the targets on the device might use the same logical addresses cause incorrect information in the device's l2p table. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-18Merge branch 'for-4.6/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block driver updates from Jens Axboe: "This is the block driver pull request for this merge window. It sits on top of for-4.6/core, that was just sent out. This contains: - A set of fixes for lightnvm. One from Alan, fixing an overflow, and the rest from the usual suspects, Javier and Matias. - A set of fixes for nbd from Markus and Dan, and a fixup from Arnd for correct usage of the signed 64-bit divider. - A set of bug fixes for the Micron mtip32xx, from Asai. - A fix for the brd discard handling from Bart. - Update the maintainers entry for cciss, since that hardware has transferred ownership. - Three bug fixes for bcache from Eric Wheeler. - Set of fixes for xen-blk{back,front} from Jan and Konrad. - Removal of the cpqarray driver. It has been disabled in Kconfig since 2013, and we were initially scheduled to remove it in 3.15. - Various updates and fixes for NVMe, with the most important being: - Removal of the per-device NVMe thread, replacing that with a watchdog timer instead. From Christoph. - Exposing the namespace WWID through sysfs, from Keith. - Set of cleanups from Ming Lin. - Logging the controller device name instead of the underlying PCI device name, from Sagi. - And a bunch of fixes and optimizations from the usual suspects in this area" * 'for-4.6/drivers' of git://git.kernel.dk/linux-block: (49 commits) NVMe: Expose ns wwid through single sysfs entry drivers:block: cpqarray clean up brd: Fix discard request processing cpqarray: remove it from the kernel cciss: update MAINTAINERS NVMe: Remove unused sq_head read in completion path bcache: fix cache_set_flush() NULL pointer dereference on OOM bcache: cleaned up error handling around register_cache() bcache: fix race of writeback thread starting before complete initialization NVMe: Create discard zero quirk white list nbd: use correct div_s64 helper mtip32xx: remove unneeded variable in mtip_cmd_timeout() lightnvm: generalize rrpc ppa calculations lightnvm: remove struct nvm_dev->total_blocks lightnvm: rename ->nr_pages to ->nr_sects lightnvm: update closed list outside of intr context xen/blback: Fit the important information of the thread in 17 characters lightnvm: fold get bb tbl when using dual/quad plane mode lightnvm: fix up nonsensical configure overrun checking xen-blkback: advertise indirect segment support earlier ...
2016-03-03lightnvm: generalize rrpc ppa calculationsJavier González
In rrpc, some calculations assume a certain configuration (e.g., 1 LUN, 1 sector per page). The reason behind this was that LightNVM used a simple configuration with QEMU to test core features in the beginning. This patch relaxes these assumptions and generalizes calculation, allowing multiple luns to be used. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-03lightnvm: remove struct nvm_dev->total_blocksMatias Bjørling
The struct nvm_dev->total_blocks was only used for calculating total sectors. Remove and instead calculate total sectors from the number of luns and its sectors. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-03lightnvm: rename ->nr_pages to ->nr_sectsMatias Bjørling
The struct rrpc->nr_pages can easily be interpreted as the number of flash pages allocated to rrpc, while it is the nr_sects. Make sure that this is reflected from the variable name. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-03lightnvm: update closed list outside of intr contextJavier González
When an I/O finishes, full blocks are moved from the open to the closed list - a lock is taken to protect the list. This happens at the moment in the interrupt context, which is not correct. This patch moves this logic to the block workqueue instead, avoiding holding a spinlock without interrupt save in an interrupt context. Signed-off-by: Javier González <javier@cnexlabs.com> Fixes: ff0e498bfa18 ("lightnvm: manage open and closed blocks sepa...") Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-03lightnvm: fold get bb tbl when using dual/quad plane modeMatias Bjørling
When the media manager runs in dual or quad plane mode, lightnvm abstracts away plane specific commands. This poses a problem for get bad block table, as it reports bad blocks per plane, making the table either two or four times bigger than expected. Fold the bad block list before returning. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-03lightnvm: fix up nonsensical configure overrun checkingAlan
Instead of checking a constant 0 actually check the space available. Even better remember to allow for the header and also check the right amount of space is needed. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-04lightnvm: allow to force mm initializationMatias Bjørling
System block allows the device to initialize with its configured media manager. The system blocks is written to disk, and read again when media manager is determined. For this to work, the backend must store the data. Device drivers, such as null_blk, does not have any backend storage. This patch allows the media manager to be initialized without a storage backend. It also fix incorrect configuration of capabilities in null_blk, as it does not support get/set bad block interface. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-04lightnvm: fix request intersection locking in rrpcJavier González
This patch fixes an error on the calculation of intersecting logical addresses; it contemplates the case where a new request including several addresses intersects with a single locked address. This case is typical when multiple pages are sent in a new request, while GC - which at the moment sends one address at the time - is running. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-04lightnvm: warn if irqs are disabled in lock laddrJavier González
Add a warning if irqs are disabled when locking a new address in rrpc. The typical path to a new request does not disable irqs, but this is not guaranteed in the future. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-04lightnvm: put bio before returnWenwei Tao
The bio is not returned if the data page cannot be allocated. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: introduce factory resetMatias Bjørling
Now that a device can be managed using the system blocks, a method to reset the device is necessary as well. This patch introduces logic to reset the device easily to factory state and exposes it through an ioctl. The ioctl takes the following flags: NVM_FACTORY_ERASE_ONLY_USER By default all blocks, except host-reserved blocks are erased upon factory reset. Instead of this, only erase host-reserved blocks. NVM_FACTORY_RESET_HOST_BLKS Mark host-reserved blocks to be erased and set their type to free. NVM_FACTORY_RESET_GRWN_BBLKS Mark "grown bad blocks" to be erased and set their type to free. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: use system block for mm initializationMatias Bjørling
Use system block information to register the appropriate media manager. This enables the LightNVM subsystem to instantiate a media manager selected by the user, instead of relying on automatic detection by each media manager loaded in the kernel. A device must now be initialized before it can proceed to initialize its media manager. Upon initialization, the configured media manager is automatically initialized as well. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: introduce ioctl to initialize deviceMatias Bjørling
Based on the previous patch, we now introduce an ioctl to initialize the device using nvm_init_sysblock and create the necessary system blocks. The user may specify the media manager that they wish to instantiate on top. Default from user-space will be "gennvm". Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: core on-disk initializationMatias Bjørling
An Open-Channel SSD shall be initialized before use. To initialize, we define an on-disk format, that keeps a small set of metadata to bring up the media manager on top of the device. The initial step is introduced to allow a user to format the disks for a given media manager. During format, a system block is stored on one to three separate luns on the device. Each lun has the system block duplicated. During initialization, the system block can be retrieved and the appropriate media manager can initialized. The on-disk format currently covers (struct nvm_system_block): - Magic value "NVMS". - Monotonic increasing sequence number. - The physical block erase count. - Version of the system block format. - Media manager type. - Media manager superblock physical address. The interface provides three functions to manage the system block: int nvm_init_sysblock(struct nvm_dev *, struct nvm_sb_info *) int nvm_get_sysblock(struct nvm *dev, struct nvm_sb_info *) int nvm_update_sysblock(struct nvm *dev, struct nvm_sb_info *) Each implement a part of the logic to manage the system block. The initialization creates the first system blocks and mark them on the device. Get retrieves the latest system block by scanning all pages in the associated system blocks. The update sysblock writes new metadata and allocates new block if necessary. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: introduce mlc lower page table mappingsMatias Bjørling
NAND MLC memories have both lower and upper pages. When programming, both of these must be written, before data can be read. However, these lower and upper pages might not placed at even and odd flash pages, but can be skipped. Therefore each flash memory has its lower pages defined, which can then be used when programming and to know when padding are necessary. This patch implements the lower page definition in the specification, and exposes it through a simple lookup table at dev->lptbl. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: add mccap supportMatias Bjørling
Some flash media has extended capabilities, such as programming SLC pages on MLC/TLC flash, erase/program suspend, scramble and encryption. MCCAP is introduced to detect support for these capabilities in the command set. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: manage open and closed blocks separatelyJavier González
LightNVM targets need to know the state of the flash block when doing flash optimizations. An example is implementing a write buffer to respect the flash page size. Currently, block state is not accounted for; the media manager only differentiates among free, bad and in-use blocks. This patch adds the logic in the generic media manager to enable targets manage blocks into open and close separately, and it implements such management in rrpc. It also adds a set of flags to describe the state of the block (open, closed, free, bad). In order to avoid taking two locks (nvm_lun and rrpc_lun) consecutively, we introduce lockless get_/put_block primitives so that the open and close list locks and future common logic is handled within the nvm_lun lock. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: reference rrpc lun in rrpc blockJavier González
Currently, a rrpc block only points to its nvm_lun. If a user wants to find the associated rrpc lun, it will have to calculate the index and look it up manually. By referencing the rrpc lun directly, this step can be omitted, at the cost of a larger memory footprint. This is important for upcoming patches that implement write buffering in rrpc. Signed-off-by: Javier González <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: introduce nvm_submit_ppaMatias Bjørling
Internal logic for both core and media managers, does not have a backing bio for issuing I/Os. Introduce nvm_submit_ppa to allow raw I/Os to be submitted to the underlying device driver. The function request the device, ppa, data buffer and its length and will submit the I/O synchronously to the device. The return value may therefore be used to detect any errors regarding the issued I/O. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: move rq->error to nvm_rq->errorMatias Bjørling
Instead of passing request error into the LightNVM modules, incorporate it into the nvm_rq. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: support multiple ppas in nvm_erase_ppaMatias Bjørling
Sometimes a user want to erase multiple PPAs at the same time. Extend nvm_erase_ppa to take multiple ppas and number of ppas to be erased. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: move the pages per block check out of the loopWenwei Tao
There is no need to check whether dev's pages per block is beyond rrpc support every time we init a lun, we only need to check it once before enter the lun init loop. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: sectors first in ppa listMatias Bjørling
The Westlake controller requires that the PPA list has sectors defined sequentially. Currently, the PPA list is created with planes first, then sectors. Change this to sectors first, then planes. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: fix locking and mempool in rrpc_lun_gcWenwei Tao
This patch fix two issues in rrpc_lun_gc 1. prio_list is protected by rrpc_lun's lock not nvm_lun's, so acquire rlun's lock instead of lun's before operate on the list. 2. we delete block from prio_list before allocating gcb, but gcb allocation may fail, we end without putting it back to the list, this makes the block won't get reclaimed in the future. To solve this issue, delete block after gcb allocation. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: put block back to gc list on its reclaim failWenwei Tao
We delete a block from the gc list before reclaim it, so put it back to the list on its reclaim fail, otherwise this block will not get reclaimed and be programmable in the future. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: check bi_error in gcWenwei Tao
We should check last io completion status before starting another one. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: refactor end_io functions for syncMatias Bjørling
To implement sync I/O support within the LightNVM core, the end_io functions are refactored to take an end_io function pointer instead of testing for initialized media manager, followed by calling its end_io function. Sync I/O can then be implemented using a callback that signal I/O completion. This is similar to the logic found in blk_to_execute_io(). By implementing it this way, the underlying device I/Os submission logic is abstracted away from core, targets, and media managers. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: refactor rqd ppa list into set/freeMatias Bjørling
A device may be driven in single, double or quad plane mode. In that case, the rqd must have either one, two, or four PPAs set for a single PPA sent to the device. Refactor this logic into their own functions to be shared by program/erase/read in the core. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: move ppa erase logic to coreMatias Bjørling
A device may function in single, dual or quad plane mode. The gennvm media manager manages this with explicit helpers. They convert a single ppa to 1, 2 or 4 separate ppas in a ppa list. To aid implementation of recovery and system blocks, this functionality can be moved directly into the core. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: unlock rq and free ppa_list on submission failWenwei Tao
When rrpc_write_ppalist_rq and rrpc_read_ppalist_rq succeed, we setup rq correctly, but nvm_submit_io may afterward fail since it cannot allocate request or nvme_nvm_command, we return error but forget to cleanup the previous work. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: add check after mempool allocationJavier Gonzalez
The mempool allocation might fail. Make sure to return error when it does, instead of causing a kernel panic. Signed-off-by: Javier Gonzalez <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: fix incorrect nr_free_blocks statChao Yu
When initing bad block list in gennvm_block_bb, once we move bad block from free_list to bb_list, we should maintain both stat info nr_free_blocks and nr_bad_blocks. So this patch fixes to add missing operation related to nr_free_blocks. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: fix bio submission issueWenwei Tao
Put bio when submission fails, since we get it before submission. And return error when backend device driver doesn't provide a submit_io method, thus we can end IO properly. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-29lightnvm: wrong offset in bad blk lun calculationMatias Bjørling
dev->nr_luns reports the total number of luns available in a device while dev->luns_per_chnl is the number of luns per channel. When multiple channels are available, the offset is calculated from a channel and lun id into a linear array. As it multiplies with the total number of luns, we go out of bound when channel id > 0 and causes the kernel to panic when we read a protected kernel memory area. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-07lightnvm: do not compile in debugging by defaultMatias Bjørling
The LightNVM module exposes a debug interface when CONFIG_NVM_DEBUG is set. This interfaces takes a string to configure media managers and targets. Make sure this interface is only exposed when chosen deliberately. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-07lightnvm: prevent gennvm module unload on useMatias Bjørling
After the gennvm module has been initialized. It might be attached to one or several devices. In that case, the module is in use. Make sure that it can not be unloaded. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-07lightnvm: fix media mgr registrationMatias Bjørling
This patch fixes two issues during media manager registration. 1. The ppa pool can be used at media manager registration. Allocate the ppa pool before that. 2. If a media manager can't be found, this should not lead to the device being unallocated. A media manager can be registered later, that can manage the device. Only warn if a media manager fails initialization. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-07lightnvm: replace req queue with nvmdev for lldMatias Bjørling
In the case where a request queue is passed to the low lever lightnvm device drive integration, the device driver might pass its admin commands through another queue. Instead pass nvm_dev, and let the low level drive the appropriate queue. Reported-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-07lightnvm: refactor spin_unlock in gennvm_get_blkWenwei Tao
The spin_unlock is duplicated multiple times. Jump to a single unlock to improve the code flow. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-07lightnvm: put blks when luns configure failedWenwei Tao
Put the allocated blocks back to the free list when the luns configure failed, to make these blocks useable to others. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-07lightnvm: use flags in rrpc_get_blkWenwei Tao
rrpc_get_blk use constant 0 as the input parameter of nvm_get_blk, this may result in getting gc block failed unexpectedly. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-29lightnvm: missing nvm_lock acquireWenwei Tao
To avoid race conditions, traverse dev, media manager, and target lists and also register, unregister entries to/from them, should be always under the nvm_lock control. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-29lightnvm: unconverted ppa returned in get_bb_tblMatias Bjørling
The get_bb_tbl function takes ppa as a generic address, which is converted to the ppa device address within the device driver. When the update_bbtbl callback is called from get_bb_tbl, the device specific ppa is used, instead of the generic ppa. Make sure to pass the generic ppa. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-29lightnvm: do device max sectors boundary check firstWenwei Tao
do device max_phys_sect boundary check first, otherwise we will allocate dma_pools for devices whose max sectors are beyond lightnvm support and register them. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-29lightnvm: fix ioctl memory leaksSudip Mukherjee
If copy_to_user() fails we returned error but we missed releasing devices. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-29lightnvm: free memory when gennvm register failsWenwei Tao
free allocated nvm block and gennvm lun structures when gennvm register fails, otherwise it will cause memory leak. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-20lightnvm: add free and bad lun info to show lunsJavier Gonzalez
Add free block, used block, and bad block information to the show debug interface. This information is used to debug how targets track blocks. Also, change debug function name to make it more generic. Signed-off-by: Javier Gonzalez <javier@cnexlabs.com> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>