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path: root/drivers/block/null_blk.c
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2018-07-24block: Rename the null_blk_mod kernel module back into null_blkBart Van Assche1-1926/+0
Commit ca4b2a011948 ("null_blk: add zone support") breaks several blktests scripts because it renamed the null_blk kernel module into null_blk_mod. Hence rename null_blk_mod back into null_blk. Fixes: ca4b2a011948 ("null_blk: add zone support") Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Cc: Matias Bjorling <matias.bjorling@wdc.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Cc: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09null_blk: add zone supportMatias Bjørling1-2/+46
Adds support for exposing a null_blk device through the zone device interface. The interface is managed with the parameters zoned and zone_size. If zoned is set, the null_blk instance registers as a zoned block device. The zone_size parameter defines how big each zone will be. Signed-off-by: Matias Bjørling <matias.bjorling@wdc.com> Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09null_blk: move shared definitions to header fileMatias Bjørling1-75/+1
Split the null_blk device driver, such that it can prepare for zoned block interface support. Signed-off-by: Matias Bjørling <matias.bjorling@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09null_blk: remove NULLB_DEV_FL_CONFIGURED on turning off nullb deviceLiu Bo1-0/+1
Currently mbps knob could only be set once before switching power knob to on, after power knob has been set at least once, there is no way to set mbps knob again due to -EBUSY. As nullb is mainly used for testing, in order to make it flexible, this removes the flag NULLB_DEV_FL_CONFIGURED so that mbps knob can be reset when power knob is off, e.g. echo 0 > /config/nullb/a/power echo 40 > /config/nullb/a/mbps echo 1 > /config/nullb/a/power So does other knobs under /config/nullb/a. Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-24Merge tag 'for-linus-20180623' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+1
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
2018-06-19block: fix timeout changes for legacy request driversChristoph Hellwig1-1/+1
blk_mq_complete_request can only be called for blk-mq drivers, but when removing the BLK_EH_HANDLED return value, two legacy request timeout methods incorrectly got switched to call blk_mq_complete_request. Call __blk_complete_request instead to reinstance the previous behavior. For that __blk_complete_request needs to be exported. Fixes: 1fc2b62e ("scsi_transport_fc: complete requests from ->timeout") Fixes: 0df0bb08 ("null_blk: complete requests from ->timeout") Reported-by: Jianchao Wang <jianchao.w.wang@oracle.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-12treewide: kzalloc() -> kcalloc()Kees Cook1-4/+5
The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-05-29null_blk: complete requests from ->timeoutChristoph Hellwig1-2/+4
By completing the request entirely in the driver we can remove the BLK_EH_HANDLED return value and thus the split responsibility between the driver and the block layer that has been causing trouble. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-24block drivers/block: Use octal not symbolic permissionsJoe Perches1-15/+15
Convert the S_<FOO> symbolic permissions to their octal equivalents as using octal and not symbolic permissions is preferred by many as more readable. see: https://lkml.org/lkml/2016/8/2/1945 Done with automated conversion via: $ ./scripts/checkpatch.pl -f --types=SYMBOLIC_PERMS --fix-inplace <files...> Miscellanea: o Wrapped modified multi-line calls to a single line where appropriate o Realign modified multi-line calls to open parenthesis Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-03-17block: Move SECTOR_SIZE and SECTOR_SHIFT definitions into <linux/blkdev.h>Bart Van Assche1-2/+0
It happens often while I'm preparing a patch for a block driver that I'm wondering: is a definition of SECTOR_SIZE and/or SECTOR_SHIFT available for this driver? Do I have to introduce definitions of these constants before I can use these constants? To avoid this confusion, move the existing definitions of SECTOR_SIZE and SECTOR_SHIFT into the <linux/blkdev.h> header file such that these become available for all block drivers. Make the SECTOR_SIZE definition in the uapi msdos_fs.h header file conditional to avoid that including that header file after <linux/blkdev.h> causes the compiler to complain about a SECTOR_SIZE redefinition. Note: the SECTOR_SIZE / SECTOR_SHIFT / SECTOR_BITS definitions have not been removed from uapi header files nor from NAND drivers in which these constants are used for another purpose than converting block layer offsets and sizes into a number of sectors. Cc: David S. Miller <davem@davemloft.net> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-03-08block: Use blk_queue_flag_*() in drivers instead of queue_flag_*()Bart Van Assche1-3/+3
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>
2018-03-06block: null_blk: fix 'Invalid parameters' when loading moduleMing Lei1-21/+25
On ARM64, the default page size has been 64K on some distributions, and we should allow ARM64 people to play null_blk. This patch fixes the issue by extend page bitmap size for supporting other non-4KB PAGE_SIZE. Cc: Bart Van Assche <Bart.VanAssche@wdc.com> Cc: Shaohua Li <shli@kernel.org> Cc: Kyungchan Koh <kkc6196@fb.com>, Cc: weiping zhang <zhangweiping@didichuxing.com> Cc: Yi Zhang <yi.zhang@redhat.com> Reported-by: Yi Zhang <yi.zhang@redhat.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-02-28block: Add 'lock' as third argument to blk_alloc_queue_node()Bart Van Assche1-1/+2
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>
2018-02-28null_blk: add 'requeue' fault attributeJens Axboe1-12/+55
Similarly to the support we have for testing/faking timeouts for null_blk, this adds support for triggering a requeue condition. Considering the issues around restart we've been seeing, this should be a useful addition to the testing arsenal to ensure that we are handling requeue conditions correctly. This works for queue mode 1 (legacy request_fn based path) and 2 (blk-mq path), as there's no good way to do requeue with a bio based driver. This is similar to the timeout path. For the blk-mq path, we alternate between passing back BLK_STS_RESOURCE and manually calling blk_mq_requeue_request() in the driver. The former will hit the core requeue path, while the latter exercises the IO scheduler requeue path. Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-30blk-mq: introduce BLK_STS_DEV_RESOURCEMing Lei1-1/+1
This status is returned from driver to block layer if device related resource is unavailable, but driver can guarantee that IO dispatch will be triggered in future when the resource is available. Convert some drivers to return BLK_STS_DEV_RESOURCE. Also, if driver returns BLK_STS_RESOURCE and SCHED_RESTART is set, rerun queue after a delay (BLK_MQ_DELAY_QUEUE) to avoid IO stalls. BLK_MQ_DELAY_QUEUE is 3 ms because both scsi-mq and nvmefc are using that magic value. If a driver can make sure there is in-flight IO, it is safe to return BLK_STS_DEV_RESOURCE because: 1) If all in-flight IOs complete before examining SCHED_RESTART in blk_mq_dispatch_rq_list(), SCHED_RESTART must be cleared, so queue is run immediately in this case by blk_mq_dispatch_rq_list(); 2) if there is any in-flight IO after/when examining SCHED_RESTART in blk_mq_dispatch_rq_list(): - if SCHED_RESTART isn't set, queue is run immediately as handled in 1) - otherwise, this request will be dispatched after any in-flight IO is completed via blk_mq_sched_restart() 3) if SCHED_RESTART is set concurently in context because of BLK_STS_RESOURCE, blk_mq_delay_run_hw_queue() will cover the above two cases and make sure IO hang can be avoided. One invariant is that queue will be rerun if SCHED_RESTART is set. Suggested-by: Jens Axboe <axboe@kernel.dk> Tested-by: Laurence Oberman <loberman@redhat.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-29Merge branch 'for-4.16/block' of git://git.kernel.dk/linux-blockLinus Torvalds1-221/+69
Pull block updates from Jens Axboe: "This is the main pull request for block IO related changes for the 4.16 kernel. Nothing major in this pull request, but a good amount of improvements and fixes all over the map. This contains: - BFQ improvements, fixes, and cleanups from Angelo, Chiara, and Paolo. - Support for SMR zones for deadline and mq-deadline from Damien and Christoph. - Set of fixes for bcache by way of Michael Lyle, including fixes from himself, Kent, Rui, Tang, and Coly. - Series from Matias for lightnvm with fixes from Hans Holmberg, Javier, and Matias. Mostly centered around pblk, and the removing rrpc 1.2 in preparation for supporting 2.0. - A couple of NVMe pull requests from Christoph. Nothing major in here, just fixes and cleanups, and support for command tracing from Johannes. - Support for blk-throttle for tracking reads and writes separately. From Joseph Qi. A few cleanups/fixes also for blk-throttle from Weiping. - Series from Mike Snitzer that enables dm to register its queue more logically, something that's alwways been problematic on dm since it's a stacked device. - Series from Ming cleaning up some of the bio accessor use, in preparation for supporting multipage bvecs. - Various fixes from Ming closing up holes around queue mapping and quiescing. - BSD partition fix from Richard Narron, fixing a problem where we can't mount newer (10/11) FreeBSD partitions. - Series from Tejun reworking blk-mq timeout handling. The previous scheme relied on atomic bits, but it had races where we would think a request had timed out if it to reused at the wrong time. - null_blk now supports faking timeouts, to enable us to better exercise and test that functionality separately. From me. - Kill the separate atomic poll bit in the request struct. After this, we don't use the atomic bits on blk-mq anymore at all. From me. - sgl_alloc/free helpers from Bart. - Heavily contended tag case scalability improvement from me. - Various little fixes and cleanups from Arnd, Bart, Corentin, Douglas, Eryu, Goldwyn, and myself" * 'for-4.16/block' of git://git.kernel.dk/linux-block: (186 commits) block: remove smart1,2.h nvme: add tracepoint for nvme_complete_rq nvme: add tracepoint for nvme_setup_cmd nvme-pci: introduce RECONNECTING state to mark initializing procedure nvme-rdma: remove redundant boolean for inline_data nvme: don't free uuid pointer before printing it nvme-pci: Suspend queues after deleting them bsg: use pr_debug instead of hand crafted macros blk-mq-debugfs: don't allow write on attributes with seq_operations set nvme-pci: Fix queue double allocations block: Set BIO_TRACE_COMPLETION on new bio during split blk-throttle: use queue_is_rq_based block: Remove kblockd_schedule_delayed_work{,_on}() blk-mq: Avoid that blk_mq_delay_run_hw_queue() introduces unintended delays blk-mq: Rename blk_mq_request_direct_issue() into blk_mq_request_issue_directly() lib/scatterlist: Fix chaining support in sgl_alloc_order() blk-throttle: track read and write request individually block: add bdev_read_only() checks to common helpers block: fail op_is_write() requests to read-only partitions blk-throttle: export io_serviced_recursive, io_service_bytes_recursive ...
2018-01-11null_blk: remove explicit 'select FAULT_INJECTION'Arnd Bergmann1-0/+8
Selecting FAULT_INJECTION causes a Kconfig warning when CONFIG_DEBUG_KERNEL is not set: warning: (BLK_DEV_NULL_BLK && DRM_I915_SELFTEST) selects FAULT_INJECTION which has unmet direct dependencies (DEBUG_KERNEL) The other drivers that use FAULT_INJECTION tend to have a separate Kconfig symbol for turning on that feature, so let's do the same thing here. This may add a bit more complexity than we like, but it avoids the warning and is more consistent with the rest of the kernel. Fixes: 93b570464cce ("null_blk: add option for managing IO timeouts") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-10null_blk: add option for managing IO timeoutsJens Axboe1-4/+42
Use the fault injection framework to provide a way for null_blk to configure timeouts. This only works for queue_mode 1 and 2, since the bio mode doesn't have code for tracking timeouts. Let's say you want to have a 10% chance of timing out every 100,000 requests, and for 5 total timeouts, you could do: modprobe null_blk timeout="100000,10,0,5" This is useful for adding blktests to test that IO timeouts are handled appropriately. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-09null_blk: wire up timeoutsJens Axboe1-0/+16
This is needed to ensure that we actually handle timeouts. Without it, the queue_mode=1 path will never call blk_add_timer(), and the queue_mode=2 path will continually just return EH_RESET_TIMER and we never actually complete the offending request. This was used to test the new timeout code, and the changes around killing off REQ_ATOM_COMPLETE. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-05null_blk: remove lightnvm supportMatias Bjørling1-217/+3
With rrpc to be removed, the null_blk lightnvm support is no longer functional. Remove the lightnvm implementation and maybe add it to another module in the future if someone takes on the challenge. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-12-20null_blk: unalign call_single_dataJens Axboe1-2/+2
Commit 966a967116e6 randomly added alignment to this structure, but it's actually detrimental to performance of null_blk. Test case: Running on both the home and remote node shows a ~5% degradation in performance. While in there, move blk_status_t to the hole after the integer tag in the nullb_cmd structure. After this patch, we shrink the size from 192 to 152 bytes. Fixes: 966a967116e69 ("smp: Avoid using two cache lines for struct call_single_data") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-22null_blk: fix dev->badblocks leakDavid Disseldorp1-1/+4
null_alloc_dev() allocates memory for dev->badblocks, but cleanup currently only occurs in the configfs release codepath, missing a number of other places. This bug was found running the blktests block/010 test, alongside kmemleak: rapido1:/blktests# ./check block/010 ... rapido1:/blktests# echo scan > /sys/kernel/debug/kmemleak [ 306.966708] kmemleak: 32 new suspected memory leaks (see /sys/kernel/debug/kmemleak) rapido1:/blktests# cat /sys/kernel/debug/kmemleak unreferenced object 0xffff88001f86d000 (size 4096): comm "modprobe", pid 231, jiffies 4294892415 (age 318.252s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff814b0379>] kmemleak_alloc+0x49/0xa0 [<ffffffff810f180f>] kmem_cache_alloc+0x9f/0xe0 [<ffffffff8124e45f>] badblocks_init+0x2f/0x60 [<ffffffffa0019fae>] 0xffffffffa0019fae [<ffffffffa0021273>] nullb_device_badblocks_store+0x63/0x130 [null_blk] [<ffffffff810004cd>] do_one_initcall+0x3d/0x170 [<ffffffff8109fe0d>] do_init_module+0x56/0x1e9 [<ffffffff8109ebd7>] load_module+0x1c47/0x26a0 [<ffffffff8109f819>] SyS_finit_module+0xa9/0xd0 [<ffffffff814b4f60>] entry_SYSCALL_64_fastpath+0x13/0x94 Fixes: 2f54a613c942 ("nullb: badbblocks support") Reviewed-by: Shaohua Li <shli@fb.com> Signed-off-by: David Disseldorp <ddiss@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-14Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+9
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 ...
2017-10-19nullb: make config_item_type constBhumika Goyal1-2/+2
Make these structures const as they are either passed to the functions having the argument as const or stored as a reference in the "ci_type" const field of a config_item structure. Done using Coccienlle. Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-10-17nullb: fix error return code in null_init()Wei Yongjun1-1/+3
Fix to return error code -ENOMEM from the null_alloc_dev() error handling case instead of 0, as done elsewhere in this function. Fixes: 2984c8684f96 ("nullb: factor disk parameters") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-30null_blk: add "no_sched" module parameterweiping zhang1-0/+6
add an option that disable io scheduler for null block device. Signed-off-by: weiping zhang <zhangweiping@didichuxing.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-07Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-blockLinus Torvalds1-95/+1214
Pull block layer updates from Jens Axboe: "This is the first pull request for 4.14, containing most of the code changes. It's a quiet series this round, which I think we needed after the churn of the last few series. This contains: - Fix for a registration race in loop, from Anton Volkov. - Overflow complaint fix from Arnd for DAC960. - Series of drbd changes from the usual suspects. - Conversion of the stec/skd driver to blk-mq. From Bart. - A few BFQ improvements/fixes from Paolo. - CFQ improvement from Ritesh, allowing idling for group idle. - A few fixes found by Dan's smatch, courtesy of Dan. - A warning fixup for a race between changing the IO scheduler and device remova. From David Jeffery. - A few nbd fixes from Josef. - Support for cgroup info in blktrace, from Shaohua. - Also from Shaohua, new features in the null_blk driver to allow it to actually hold data, among other things. - Various corner cases and error handling fixes from Weiping Zhang. - Improvements to the IO stats tracking for blk-mq from me. Can drastically improve performance for fast devices and/or big machines. - Series from Christoph removing bi_bdev as being needed for IO submission, in preparation for nvme multipathing code. - Series from Bart, including various cleanups and fixes for switch fall through case complaints" * 'for-4.14/block' of git://git.kernel.dk/linux-block: (162 commits) kernfs: checking for IS_ERR() instead of NULL drbd: remove BIOSET_NEED_RESCUER flag from drbd_{md_,}io_bio_set drbd: Fix allyesconfig build, fix recent commit drbd: switch from kmalloc() to kmalloc_array() drbd: abort drbd_start_resync if there is no connection drbd: move global variables to drbd namespace and make some static drbd: rename "usermode_helper" to "drbd_usermode_helper" drbd: fix race between handshake and admin disconnect/down drbd: fix potential deadlock when trying to detach during handshake drbd: A single dot should be put into a sequence. drbd: fix rmmod cleanup, remove _all_ debugfs entries drbd: Use setup_timer() instead of init_timer() to simplify the code. drbd: fix potential get_ldev/put_ldev refcount imbalance during attach drbd: new disk-option disable-write-same drbd: Fix resource role for newly created resources in events2 drbd: mark symbols static where possible drbd: Send P_NEG_ACK upon write error in protocol != C drbd: add explicit plugging when submitting batches drbd: change list_for_each_safe to while(list_first_entry_or_null) drbd: introduce drbd_recv_header_maybe_unplug ...
2017-08-29smp: Avoid using two cache lines for struct call_single_dataYing Huang1-1/+1
struct call_single_data is used in IPIs to transfer information between CPUs. Its size is bigger than sizeof(unsigned long) and less than cache line size. Currently it is not allocated with any explicit alignment requirements. This makes it possible for allocated call_single_data to cross two cache lines, which results in double the number of the cache lines that need to be transferred among CPUs. This can be fixed by requiring call_single_data to be aligned with the size of call_single_data. Currently the size of call_single_data is the power of 2. If we add new fields to call_single_data, we may need to add padding to make sure the size of new definition is the power of 2 as well. Fortunately, this is enforced by GCC, which will report bad sizes. To set alignment requirements of call_single_data to the size of call_single_data, a struct definition and a typedef is used. To test the effect of the patch, I used the vm-scalability multiple thread swap test case (swap-w-seq-mt). The test will create multiple threads and each thread will eat memory until all RAM and part of swap is used, so that huge number of IPIs are triggered when unmapping memory. In the test, the throughput of memory writing improves ~5% compared with misaligned call_single_data, because of faster IPIs. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Huang, Ying <ying.huang@intel.com> [ Add call_single_data_t and align with size of call_single_data. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Aaron Lu <aaron.lu@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/87bmnqd6lz.fsf@yhuang-mobile.sh.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-28null_blk: use available 'dev' in nullb_device_power_store()Jens Axboe1-1/+1
We already have this pointer, no need to use to_nullb_device() again. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-28block/nullb: delete unnecessary memory freeShaohua Li1-1/+0
Commit 2984c86(nullb: factor disk parameters) has a typo. The nullb_device allocation/free is done outside of null_add_dev. The commit accidentally frees the nullb_device in error code path. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-25block/nullb: fix NULL dereferenceShaohua Li1-1/+1
Dan reported this: The patch 2984c8684f96: "nullb: factor disk parameters" from Aug 14, 2017, leads to the following Smatch complaint: drivers/block/null_blk.c:1759 null_init_tag_set() error: we previously assumed 'nullb' could be null (see line 1750) 1755 set->cmd_size = sizeof(struct nullb_cmd); 1756 set->flags = BLK_MQ_F_SHOULD_MERGE; 1757 set->driver_data = NULL; 1758 1759 if (nullb->dev->blocking) ^^^^^^^^^^^^^^^^^^^^ And an unchecked dereference. nullb could be NULL here. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-25null_blk: update email adressJens Axboe1-1/+1
Update to a working one, the fusionio address hasn't been valid in 4 years. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23nullb: badbblocks supportShaohua Li1-1/+88
Sometime disk could have tracks broken and data there is inaccessable, but data in other parts can be accessed in normal way. MD RAID supports such disks. But we don't have a good way to test it, because we can't control which part of a physical disk is bad. For a virtual disk, this can be easily controlled. This patch adds a new 'badblock' attribute. Configure it in this way: echo "+1-100" > xxx/badblock, this will make sector [1-100] as bad blocks. echo "-20-30" > xxx/badblock, this will make sector [20-30] good If badblocks are accessed, the nullb disk will return IO error. Other parts of the disk can accessed in normal way. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23nullb: emulate cacheShaohua Li1-30/+231
Software must flush disk cache to guarantee data safety. To check if software correctly does disk cache flush, we must know the behavior of disk. But physical disk behavior is uncontrollable. Even software doesn't do the flush, the disk probably does the flush. This patch tries to emulate a cache in the test disk. All write will go to a cache first, when the cache is full, we then flush some data to disk storage. A flush request will flush all data of the cache to disk storage. A FUA write will write to memory store directly and revalidate data in cache. If there is a power failure (by writing to power attribute, 'echo 0 > disk_name/power'), we discard all data in the cache, but preserve the data in disk storage. Later we can power on the disk again as usual (write 1 to 'power' attribute), then we can check data integrity and very if software does everything correctly. A new attribute 'cache_size' (in MB) is added to configure cache size. Based on original patch from Kyungchan Koh Signed-off-by: Kyungchan Koh <kkc6196@fb.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23nullb: bandwidth controlShaohua Li1-2/+114
In test, we usually expect controllable disk speed. For example, in a raid array, we'd like some disks are fast and some are slow. MD RAID actually has a feature for this. To test the feature, we'd like to make the disk run in specific speed. block throttling probably can be used for this purpose, but it requires cgroup setup. Here we just implement a simple throttling mechanism in the driver. There is slight fluctuation in the mechanism, but it's good enough for test. To configure the bandwidth cap, user sets the 'mbps' attribute. mbps is MB/s. Based on original patch from Kyungchan Koh Signed-off-by: Kyungchan Koh <kkc6196@fb.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23nullb: support discardShaohua Li1-1/+41
discard makes sense for memory backed disk. And also it's useful to test if upper layer supports dicard correctly. User configures 'discard' attribute to enable/disable dicard support. Based on original patch from Kyungchan Koh Signed-off-by: Kyungchan Koh <kkc6196@fb.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23nullb: support memory backed storeShaohua Li1-9/+330
This adds memory backed store in nullb. User configure 'memory_backed' attribute for this. By default, nullb disk doesn't use memory backed store. Based on original patch from Kyungchan Koh Signed-off-by: Kyungchan Koh <kkc6196@fb.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23nullb: use ida to manage indexShaohua Li1-2/+4
We now dynamically create disks. Managing the disk index with ida to avoid bump up the index too much. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23nullb: add interface to power on diskShaohua Li1-0/+80
The device created in nullb configfs interface isn't power on by default. After user configures the device, user can do 'echo 1 > xxx/nullb/device_name/power' to power on the device, which will create a disk. the xxx/nullb/device_name/index is the disk index, so if the index is 2, the new created disk should be named as /dev/nullb2. Note, the 'index' is only valid after disk is power on. 'echo 0 > xxx/nullb/device_name/power' will remove the disk. Note, this doesn't remove the device. To remove the device, user should do 'rmdir xxx/nullb/device_name'. Removing the device will remove the disk too. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23nullb: add configfs interfaceShaohua Li1-1/+209
Add configfs interface for nullb. configfs interface is more flexible and easy to configure in a per-disk basis. Configuration is something like this: mount -t configfs none /mnt Checking which features the driver supports: cat /mnt/nullb/features The 'features' attribute is for future extension. We probably will add new features into the driver, userspace can check this attribute to find the supported features. Create/remove a device: mkdir/rmdir /mnt/nullb/a Then configure the device by setting attributes under /mnt/nullb/a, most of nullb supported module parameters are converted to attributes: size; /* device size in MB */ completion_nsec; /* time in ns to complete a request */ submit_queues; /* number of submission queues */ home_node; /* home node for the device */ queue_mode; /* block interface */ blocksize; /* block size */ irqmode; /* IRQ completion handler */ hw_queue_depth; /* queue depth */ use_lightnvm; /* register as a LightNVM device */ blocking; /* blocking blk-mq device */ use_per_node_hctx; /* use per-node allocation for hardware context */ Note, creating a device doesn't create a disk immediately. Creating a disk is done in two phases: create a device and then power on the device. Next patch will introduce device power on. Based on original patch from Kyungchan Koh Signed-off-by: Kyungchan Koh <kkc6196@fb.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23nullb: factor disk parametersShaohua Li1-81/+153
When we switch to configfs interface, each disk could have different configuration. To prepare for the change, we move most disk setting to a separate data structure. The existing module parameter interface is kept. The 'nr_devices' and 'shared_tags' don't make sense for per-disk setting, so they are remained as global settings. Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-07null_blk: make sure submit_queues > 0weiping zhang1-2/+2
set submit_queues to 1 by default, and make sure it's value > 0. Signed-off-by: weiping zhang <zhangweiping@didichuxing.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-07null_blk: simplify logic for use_per_node_hctxweiping zhang1-5/+2
make sure submit_queues equal nr_online_nodes. Signed-off-by: weiping zhang <zhangweiping@didichuxing.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-06null_blk: fix error flow for shared tags during module_initMax Gurtovoy1-5/+13
In case we use shared tags feature, blk_mq_alloc_tag_set might fail during module initialization. In that case, fail the load with a suitable error code. Also move the tagset initialization process after defining the amount of submission queues. Signed-off-by: Max Gurtovoy <maxg@mellanox.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20null_blk: add support for shared tagsJens Axboe1-42/+70
Some storage drivers need to share tag sets between devices. It's useful to be able to model that with null_blk, to find hangs or performance issues. Add a 'shared_tags' bool module parameter that. If that is set to true and nr_devices is bigger than 1, all devices allocated will share the same tag set. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-09blk-mq: switch ->queue_rq return value to blk_status_tChristoph Hellwig1-2/+2
Use the same values for use for request completion errors as the return value from ->queue_rq. BLK_STS_RESOURCE is special cased to cause a requeue, and all the others are completed as-is. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-09block: introduce new block status code typeChristoph Hellwig1-4/+5
Currently we use nornal Linux errno values in the block layer, and while we accept any error a few have overloaded magic meanings. This patch instead introduces a new blk_status_t value that holds block layer specific status codes and explicitly explains their meaning. Helpers to convert from and to the previous special meanings are provided for now, but I suspect we want to get rid of them in the long run - those drivers that have a errno input (e.g. networking) usually get errnos that don't know about the special block layer overloads, and similarly returning them to userspace will usually return somethings that strictly speaking isn't correct for file system operations, but that's left as an exercise for later. For now the set of errors is a very limited set that closely corresponds to the previous overloaded errno values, but there is some low hanging fruite to improve it. blk_status_t (ab)uses the sparse __bitwise annotations to allow for sparse typechecking, so that we can easily catch places passing the wrong values. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20blk-mq: remove the error argument to blk_mq_complete_requestChristoph Hellwig1-1/+1
Now that all drivers that call blk_mq_complete_requests have a ->complete callback we can remove the direct call to blk_mq_end_request, as well as the error argument to blk_mq_complete_request. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20null_blk: don't pass always-0 req->errors to blk_mq_complete_requestChristoph Hellwig1-1/+1
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-19null_blk: Use blk_init_request_from_bio() instead of open-coding itBart Van Assche1-8/+1
This patch changes the behavior of the null_blk driver for the LightNVM mode as follows: * REQ_FAILFAST_MASK is set for read-ahead requests. * If no I/O priority has been set in the bio, the I/O priority is copied from the I/O context. * The rq_disk member is initialized if bio->bi_bdev != NULL. * req->errors is initialized to zero. Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Matias Bjørling <m@bjorling.me> Cc: Adam Manzanares <adam.manzanares@wdc.com> Signed-off-by: Jens Axboe <axboe@fb.com>