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2018-08-22Merge tag 'for-4.19/post-20180822' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull more block updates from Jens Axboe: - Set of bcache fixes and changes (Coly) - The flush warn fix (me) - Small series of BFQ fixes (Paolo) - wbt hang fix (Ming) - blktrace fix (Steven) - blk-mq hardware queue count update fix (Jianchao) - Various little fixes * tag 'for-4.19/post-20180822' of git://git.kernel.dk/linux-block: (31 commits) block/DAC960.c: make some arrays static const, shrinks object size blk-mq: sync the update nr_hw_queues with blk_mq_queue_tag_busy_iter blk-mq: init hctx sched after update ctx and hctx mapping block: remove duplicate initialization tracing/blktrace: Fix to allow setting same value pktcdvd: fix setting of 'ret' error return for a few cases block: change return type to bool block, bfq: return nbytes and not zero from struct cftype .write() method block, bfq: improve code of bfq_bfqq_charge_time block, bfq: reduce write overcharge block, bfq: always update the budget of an entity when needed block, bfq: readd missing reset of parent-entity service blk-wbt: fix IO hang in wbt_wait() block: don't warn for flush on read-only device bcache: add the missing comments for smp_mb()/smp_wmb() bcache: remove unnecessary space before ioctl function pointer arguments bcache: add missing SPDX header bcache: move open brace at end of function definitions to next line bcache: add static const prefix to char * array declarations bcache: fix code comments style ...
2018-08-21blk-mq: sync the update nr_hw_queues with blk_mq_queue_tag_busy_iterJianchao Wang
For blk-mq, part_in_flight/rw will invoke blk_mq_in_flight/rw to account the inflight requests. It will access the queue_hw_ctx and nr_hw_queues w/o any protection. When updating nr_hw_queues and blk_mq_in_flight/rw occur concurrently, panic comes up. Before update nr_hw_queues, the q will be frozen. So we could use q_usage_counter to avoid the race. percpu_ref_is_zero is used here so that we will not miss any in-flight request. The access to nr_hw_queues and queue_hw_ctx in blk_mq_queue_tag_busy_iter are under rcu critical section, __blk_mq_update_nr_hw_queues could use synchronize_rcu to ensure the zeroed q_usage_counter to be globally visible. Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-08-21blk-mq: init hctx sched after update ctx and hctx mappingJianchao Wang
Currently, when update nr_hw_queues, IO scheduler's init_hctx will be invoked before the mapping between ctx and hctx is adapted correctly by blk_mq_map_swqueue. The IO scheduler init_hctx (kyber) may depend on this mapping and get wrong result and panic finally. A simply way to fix this is that switch the IO scheduler to 'none' before update the nr_hw_queues, and then switch it back after update nr_hw_queues. blk_mq_sched_init_/exit_hctx are removed due to nobody use them any more. Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-08-14Merge tag 'for-4.19/block-20180812' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block updates from Jens Axboe: "First pull request for this merge window, there will also be a followup request with some stragglers. This pull request contains: - Fix for a thundering heard issue in the wbt block code (Anchal Agarwal) - A few NVMe pull requests: * Improved tracepoints (Keith) * Larger inline data support for RDMA (Steve Wise) * RDMA setup/teardown fixes (Sagi) * Effects log suppor for NVMe target (Chaitanya Kulkarni) * Buffered IO suppor for NVMe target (Chaitanya Kulkarni) * TP4004 (ANA) support (Christoph) * Various NVMe fixes - Block io-latency controller support. Much needed support for properly containing block devices. (Josef) - Series improving how we handle sense information on the stack (Kees) - Lightnvm fixes and updates/improvements (Mathias/Javier et al) - Zoned device support for null_blk (Matias) - AIX partition fixes (Mauricio Faria de Oliveira) - DIF checksum code made generic (Max Gurtovoy) - Add support for discard in iostats (Michael Callahan / Tejun) - Set of updates for BFQ (Paolo) - Removal of async write support for bsg (Christoph) - Bio page dirtying and clone fixups (Christoph) - Set of bcache fix/changes (via Coly) - Series improving blk-mq queue setup/teardown speed (Ming) - Series improving merging performance on blk-mq (Ming) - Lots of other fixes and cleanups from a slew of folks" * tag 'for-4.19/block-20180812' of git://git.kernel.dk/linux-block: (190 commits) blkcg: Make blkg_root_lookup() work for queues in bypass mode bcache: fix error setting writeback_rate through sysfs interface null_blk: add lock drop/acquire annotation Blk-throttle: reduce tail io latency when iops limit is enforced block: paride: pd: mark expected switch fall-throughs block: Ensure that a request queue is dissociated from the cgroup controller block: Introduce blk_exit_queue() blkcg: Introduce blkg_root_lookup() block: Remove two superfluous #include directives blk-mq: count the hctx as active before allocating tag block: bvec_nr_vecs() returns value for wrong slab bcache: trivial - remove tailing backslash in macro BTREE_FLAG bcache: make the pr_err statement used for ENOENT only in sysfs_attatch section bcache: set max writeback rate when I/O request is idle bcache: add code comments for bset.c bcache: fix mistaken comments in request.c bcache: fix mistaken code comments in bcache.h bcache: add a comment in super.c bcache: avoid unncessary cache prefetch bch_btree_node_get() bcache: display rate debug parameters to 0 when writeback is not running ...
2018-08-09blk-mq: count the hctx as active before allocating tagJianchao Wang
Currently, we count the hctx as active after allocate driver tag successfully. If a previously inactive hctx try to get tag first time, it may fails and need to wait. However, due to the stale tag ->active_queues, the other shared-tags users are still able to occupy all driver tags while there is someone waiting for tag. Consequently, even if the previously inactive hctx is waked up, it still may not be able to get a tag and could be starved. To fix it, we count the hctx as active before try to allocate driver tag, then when it is waiting the tag, the other shared-tag users will reserve budget for it. Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-27Merge tag 'for-linus-20180727' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: "Bigger than usual at this time, mostly due to the O_DIRECT corruption issue and the fact that I was on vacation last week. This contains: - NVMe pull request with two fixes for the FC code, and two target fixes (Christoph) - a DIF bio reset iteration fix (Greg Edwards) - two nbd reply and requeue fixes (Josef) - SCSI timeout fixup (Keith) - a small series that fixes an issue with bio_iov_iter_get_pages(), which ended up causing corruption for larger sized O_DIRECT writes that ended up racing with buffered writes (Martin Wilck)" * tag 'for-linus-20180727' of git://git.kernel.dk/linux-block: block: reset bi_iter.bi_done after splitting bio block: bio_iov_iter_get_pages: pin more pages for multi-segment IOs blkdev: __blkdev_direct_IO_simple: fix leak in error case block: bio_iov_iter_get_pages: fix size of last iovec nvmet: only check for filebacking on -ENOTBLK nvmet: fixup crash on NULL device path scsi: set timed out out mq requests to complete blk-mq: export setting request completion state nvme: if_ready checks to fail io to deleting controller nvmet-fc: fix target sgl list on large transfers nbd: handle unexpected replies better nbd: don't requeue the same request twice.
2018-07-24blk-mq: export setting request completion stateKeith Busch
This is preparing for drivers that want to directly alter the state of their requests. No functional change here. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-22blk-mq: fail the request in case issue failureMing Lei
Inside blk_mq_try_issue_list_directly(), if the request is issued as failed, we shouldn't try to do it again, otherwise the warning in blk_mq_start_request() will be triggered. This change is aligned to behaviour of other ways of request issue & dispatch. Fixes: 6ce3dd6eec1 ("blk-mq: issue directly if hw queue isn't busy in case of 'none'") Cc: Kashyap Desai <kashyap.desai@broadcom.com> Cc: Laurence Oberman <loberman@redhat.com> Cc: Omar Sandoval <osandov@fb.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Bart Van Assche <bart.vanassche@wdc.com> Cc: Hannes Reinecke <hare@suse.de> Cc: Kashyap Desai <kashyap.desai@broadcom.com> Cc: kernel test robot <rong.a.chen@intel.com> Cc: LKP <lkp@01.org> Reported-by: kernel test robot <rong.a.chen@intel.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-17blk-mq: issue directly if hw queue isn't busy in case of 'none'Ming Lei
In case of 'none' io scheduler, when hw queue isn't busy, it isn't necessary to enqueue request to sw queue and dequeue it from sw queue because request may be submitted to hw queue asap without extra cost, meantime there shouldn't be much request in sw queue, and we don't need to worry about effect on IO merge. There are still some single hw queue SCSI HBAs(HPSA, megaraid_sas, ...) which may connect high performance devices, so 'none' is often required for obtaining good performance. This patch improves IOPS and decreases CPU unilization on megaraid_sas, per Kashyap's test. Cc: Kashyap Desai <kashyap.desai@broadcom.com> Cc: Laurence Oberman <loberman@redhat.com> Cc: Omar Sandoval <osandov@fb.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Bart Van Assche <bart.vanassche@wdc.com> Cc: Hannes Reinecke <hare@suse.de> Reported-by: Kashyap Desai <kashyap.desai@broadcom.com> Tested-by: Kashyap Desai <kashyap.desai@broadcom.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09block: remove external dependency on wbt_flagsJosef Bacik
We don't really need to save this stuff in the core block code, we can just pass the bio back into the helpers later on to derive the same flags and update the rq->wbt_flags appropriately. Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09blk-rq-qos: refactor out common elements of blk-wbtJosef Bacik
blkcg-qos is going to do essentially what wbt does, only on a cgroup basis. Break out the common code that will be shared between blkcg-qos and wbt into blk-rq-qos.* so they can both utilize the same infrastructure. Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09blk-mq: dequeue request one by one from sw queue if hctx is busyMing Lei
It won't be efficient to dequeue request one by one from sw queue, but we have to do that when queue is busy for better merge performance. This patch takes the Exponential Weighted Moving Average(EWMA) to figure out if queue is busy, then only dequeue request one by one from sw queue when queue is busy. Fixes: b347689ffbca ("blk-mq-sched: improve dispatching from sw queue") Cc: Kashyap Desai <kashyap.desai@broadcom.com> Cc: Laurence Oberman <loberman@redhat.com> Cc: Omar Sandoval <osandov@fb.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Bart Van Assche <bart.vanassche@wdc.com> Cc: Hannes Reinecke <hare@suse.de> Reported-by: Kashyap Desai <kashyap.desai@broadcom.com> Tested-by: Kashyap Desai <kashyap.desai@broadcom.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09blk-mq: use list_splice_tail_init() to insert requestsMing Lei
list_splice_tail_init() is much more faster than inserting each request one by one, given all requets in 'list' belong to same sw queue and ctx->lock is required to insert requests. Cc: Laurence Oberman <loberman@redhat.com> Cc: Omar Sandoval <osandov@fb.com> Cc: Bart Van Assche <bart.vanassche@wdc.com> Tested-by: Kashyap Desai <kashyap.desai@broadcom.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09blk-mq: fix typo in a function commentMinwoo Im
Fix typo in a function blk_mq_alloc_tag_set() comment. if if it too large -> if it's too large. Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09blk-mq: code clean-up by adding an API to clear set->mq_mapMinwoo Im
set->mq_map is now currently cleared if something goes wrong when establishing a queue map in blk-mq-pci.c. It's also cleared before updating a queue map in blk_mq_update_queue_map(). This patch provides an API to clear set->mq_map to make it clear. Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09blk-mq: remove synchronize_rcu() from blk_mq_del_queue_tag_set()Ming Lei
We have to remove synchronize_rcu() from blk_queue_cleanup(), otherwise long delay can be caused during lun probe. For removing it, we have to avoid to iterate the set->tag_list in IO path, eg, blk_mq_sched_restart(). This patch reverts 5b79413946d (Revert "blk-mq: don't handle TAG_SHARED in restart"). Given we have fixed enough IO hang issue, and there isn't any reason to restart all queues in one tags any more, see the following reasons: 1) blk-mq core can deal with shared-tags case well via blk_mq_get_driver_tag(), which can wake up queues waiting for driver tag. 2) SCSI is a bit special because it may return BLK_STS_RESOURCE if queue, target or host is ready, but SCSI built-in restart can cover all these well, see scsi_end_request(), queue will be rerun after any request initiated from this host/target is completed. In my test on scsi_debug(8 luns), this patch may improve IOPS by 20% ~ 30% when running I/O on these 8 luns concurrently. Fixes: 705cda97ee3a ("blk-mq: Make it safe to use RCU to iterate over blk_mq_tag_set.tag_list") Cc: Omar Sandoval <osandov@fb.com> Cc: Bart Van Assche <bart.vanassche@wdc.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Martin K. Petersen <martin.petersen@oracle.com> Cc: linux-scsi@vger.kernel.org Reported-by: Andrew Jones <drjones@redhat.com> Tested-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09blk-mq: introduce new lock for protecting hctx->dispatch_waitMing Lei
Now hctx->lock is only acquired when adding hctx->dispatch_wait to one wait queue, but not held when removing it from the wait queue. IO hang can be observed easily if SCHED RESTART is disabled, that means now RESTART exits just for fixing the issue in blk_mq_mark_tag_wait(). This patch fixes the issue by introducing hctx->dispatch_wait_lock and holding it for removing hctx->dispatch_wait in blk_mq_dispatch_wake(), since we need to avoid acquiring hctx->lock in irq context. Fixes: eb619fdb2d4cb8b3d3419 ("blk-mq: fix issue with shared tag queue re-running") Cc: Christoph Hellwig <hch@lst.de> Cc: Omar Sandoval <osandov@fb.com> Cc: Bart Van Assche <bart.vanassche@wdc.com> Tested-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09blk-mq: don't pass **hctx to blk_mq_mark_tag_wait()Ming Lei
'hctx' won't be changed at all, so not necessary to pass '**hctx' to blk_mq_mark_tag_wait(). Cc: Christoph Hellwig <hch@lst.de> Cc: Bart Van Assche <bart.vanassche@wdc.com> Tested-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09blk-mq: cleanup blk_mq_get_driver_tag()Ming Lei
We never pass 'wait' as true to blk_mq_get_driver_tag(), and hence we never change '**hctx' as well. The last use of these went away with the flush cleanup, commit 0c2a6fe4dc3e. So cleanup the usage and remove the two extra parameters. Cc: Bart Van Assche <bart.vanassche@wdc.com> Cc: Christoph Hellwig <hch@lst.de> Tested-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-30Merge tag 'for-linus-20180629' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: "Small set of fixes for this series. Mostly just minor fixes, the only oddball in here is the sg change. The sg change came out of the stall fix for NVMe, where we added a mempool and limited us to a single page allocation. CONFIG_SG_DEBUG sort-of ruins that, since we'd need to account for that. That's actually a generic problem, since lots of drivers need to allocate SG lists. So this just removes support for CONFIG_SG_DEBUG, which I added back in 2007 and to my knowledge it was never useful. Anyway, outside of that, this pull contains: - clone of request with special payload fix (Bart) - drbd discard handling fix (Bart) - SATA blk-mq stall fix (me) - chunk size fix (Keith) - double free nvme rdma fix (Sagi)" * tag 'for-linus-20180629' of git://git.kernel.dk/linux-block: sg: remove ->sg_magic member drbd: Fix drbd_request_prepare() discard handling blk-mq: don't queue more if we get a busy return block: Fix cloning of requests with a special payload nvme-rdma: fix possible double free of controller async event buffer block: Fix transfer when chunk sectors exceeds max
2018-06-29blk-mq: don't queue more if we get a busy returnJens Axboe
Some devices have different queue limits depending on the type of IO. A classic case is SATA NCQ, where some commands can queue, but others cannot. If we have NCQ commands inflight and encounter a non-queueable command, the driver returns busy. Currently we attempt to dispatch more from the scheduler, if we were able to queue some commands. But for the case where we ended up stopping due to BUSY, we should not attempt to retrieve more from the scheduler. If we do, we can get into a situation where we attempt to queue a non-queueable command, get BUSY, then successfully retrieve more commands from that scheduler and queue those. This can repeat forever, starving the non-queuable command indefinitely. Fix this by NOT attempting to pull more commands from the scheduler, if we get a BUSY return. This should also be more optimal in terms of letting requests stay in the scheduler for as long as possible, if we get a BUSY due to the regular out-of-tags condition. Reviewed-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-24Merge tag 'for-linus-20180623' of git://git.kernel.dk/linux-blockLinus Torvalds
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
2018-06-23blk-mq: Fix timeout handling in case the timeout handler returns BLK_EH_DONEBart Van Assche
Make sure that RQF_TIMED_OUT is cleared when a request is reused after a block driver timeout handler has returned BLK_EH_DONE. Fixes: da6612673988 ("blk-mq: don't time out requests again that are in the timeout handler") Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Jianchao Wang <jianchao.w.wang@oracle.com> Cc: Andrew Randrianasulu <randrianasulu@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-17Merge tag 'for-linus-20180616' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: "A collection of fixes that should go into -rc1. This contains: - bsg_open vs bsg_unregister race fix (Anatoliy) - NVMe pull request from Christoph, with fixes for regressions in this window, FC connect/reconnect path code unification, and a trace point addition. - timeout fix (Christoph) - remove a few unused functions (Christoph) - blk-mq tag_set reinit fix (Roman)" * tag 'for-linus-20180616' of git://git.kernel.dk/linux-block: bsg: fix race of bsg_open and bsg_unregister block: remov blk_queue_invalidate_tags nvme-fabrics: fix and refine state checks in __nvmf_check_ready nvme-fabrics: handle the admin-only case properly in nvmf_check_ready nvme-fabrics: refactor queue ready check blk-mq: remove blk_mq_tagset_iter nvme: remove nvme_reinit_tagset nvme-fc: fix nulling of queue data on reconnect nvme-fc: remove reinit_request routine blk-mq: don't time out requests again that are in the timeout handler nvme-fc: change controllers first connect to use reconnect path nvme: don't rely on the changed namespace list log nvmet: free smart-log buffer after use nvme-rdma: fix error flow during mapping request data nvme: add bio remapping tracepoint nvme: fix NULL pointer dereference in nvme_init_subsystem blk-mq: reinit q->tag_set_list entry only after grace period
2018-06-14blk-mq: don't time out requests again that are in the timeout handlerChristoph Hellwig
We can currently call the timeout handler again on a request that has already been handed over to the timeout handler. Prevent that with a new flag. Fixes: 12f5b931 ("blk-mq: Remove generation seqeunce") Reported-by: Andrew Randrianasulu <randrianasulu@gmail.com> Tested-by: Andrew Randrianasulu <randrianasulu@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-12treewide: kzalloc_node() -> kcalloc_node()Kees Cook
The kzalloc_node() function has a 2-factor argument form, kcalloc_node(). This patch replaces cases of: kzalloc_node(a * b, gfp, node) with: kcalloc_node(a * b, gfp, node) as well as handling cases of: kzalloc_node(a * b * c, gfp, node) with: kzalloc_node(array3_size(a, b, c), gfp, node) as it's slightly less ugly than: kcalloc_node(array_size(a, b), c, gfp, node) This does, however, attempt to ignore constant size factors like: kzalloc_node(4 * 1024, gfp, node) 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_node( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc_node( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc_node( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc_node( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc_node( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc_node( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc_node( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc_node( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc_node( - sizeof(char) * COUNT + COUNT , ...) | kzalloc_node( - 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_node + kcalloc_node ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc_node + kcalloc_node ( - 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_node( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc_node( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc_node( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc_node( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc_node( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc_node( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc_node( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc_node( - 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_node( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc_node( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc_node( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc_node( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc_node( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc_node( - 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_node( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc_node( - 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_node(C1 * C2 * C3, ...) | kzalloc_node( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc_node( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc_node( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc_node( - 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_node(sizeof(THING) * C2, ...) | kzalloc_node(sizeof(TYPE) * C2, ...) | kzalloc_node(C1 * C2 * C3, ...) | kzalloc_node(C1 * C2, ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc_node + kcalloc_node ( - (E1) * E2 + E1, E2 , ...) | - kzalloc_node + kcalloc_node ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc_node + kcalloc_node ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-11blk-mq: reinit q->tag_set_list entry only after grace periodRoman Pen
It is not allowed to reinit q->tag_set_list list entry while RCU grace period has not completed yet, otherwise the following soft lockup in blk_mq_sched_restart() happens: [ 1064.252652] watchdog: BUG: soft lockup - CPU#12 stuck for 23s! [fio:9270] [ 1064.254445] task: ffff99b912e8b900 task.stack: ffffa6d54c758000 [ 1064.254613] RIP: 0010:blk_mq_sched_restart+0x96/0x150 [ 1064.256510] Call Trace: [ 1064.256664] <IRQ> [ 1064.256824] blk_mq_free_request+0xea/0x100 [ 1064.256987] msg_io_conf+0x59/0xd0 [ibnbd_client] [ 1064.257175] complete_rdma_req+0xf2/0x230 [ibtrs_client] [ 1064.257340] ? ibtrs_post_recv_empty+0x4d/0x70 [ibtrs_core] [ 1064.257502] ibtrs_clt_rdma_done+0xd1/0x1e0 [ibtrs_client] [ 1064.257669] ib_create_qp+0x321/0x380 [ib_core] [ 1064.257841] ib_process_cq_direct+0xbd/0x120 [ib_core] [ 1064.258007] irq_poll_softirq+0xb7/0xe0 [ 1064.258165] __do_softirq+0x106/0x2a2 [ 1064.258328] irq_exit+0x92/0xa0 [ 1064.258509] do_IRQ+0x4a/0xd0 [ 1064.258660] common_interrupt+0x7a/0x7a [ 1064.258818] </IRQ> Meanwhile another context frees other queue but with the same set of shared tags: [ 1288.201183] INFO: task bash:5910 blocked for more than 180 seconds. [ 1288.201833] bash D 0 5910 5820 0x00000000 [ 1288.202016] Call Trace: [ 1288.202315] schedule+0x32/0x80 [ 1288.202462] schedule_timeout+0x1e5/0x380 [ 1288.203838] wait_for_completion+0xb0/0x120 [ 1288.204137] __wait_rcu_gp+0x125/0x160 [ 1288.204287] synchronize_sched+0x6e/0x80 [ 1288.204770] blk_mq_free_queue+0x74/0xe0 [ 1288.204922] blk_cleanup_queue+0xc7/0x110 [ 1288.205073] ibnbd_clt_unmap_device+0x1bc/0x280 [ibnbd_client] [ 1288.205389] ibnbd_clt_unmap_dev_store+0x169/0x1f0 [ibnbd_client] [ 1288.205548] kernfs_fop_write+0x109/0x180 [ 1288.206328] vfs_write+0xb3/0x1a0 [ 1288.206476] SyS_write+0x52/0xc0 [ 1288.206624] do_syscall_64+0x68/0x1d0 [ 1288.206774] entry_SYSCALL_64_after_hwframe+0x3d/0xa2 What happened is the following: 1. There are several MQ queues with shared tags. 2. One queue is about to be freed and now task is in blk_mq_del_queue_tag_set(). 3. Other CPU is in blk_mq_sched_restart() and loops over all queues in tag list in order to find hctx to restart. Because linked list entry was modified in blk_mq_del_queue_tag_set() without proper waiting for a grace period, blk_mq_sched_restart() never ends, spining in list_for_each_entry_rcu_rr(), thus soft lockup. Fix is simple: reinit list entry after an RCU grace period elapsed. Fixes: Fixes: 705cda97ee3a ("blk-mq: Make it safe to use RCU to iterate over blk_mq_tag_set.tag_list") Cc: stable@vger.kernel.org Cc: Sagi Grimberg <sagi@grimberg.me> Cc: linux-block@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-04blk-mq: return when hctx is stopped in blk_mq_run_work_fnJianchao Wang
If a hardware queue is stopped, it should not be run again before explicitly started. Ignore stopped queues in blk_mq_run_work_fn(), fixing a regression recently introduced when the START_ON_RUN bit was removed. Fixes: 15fe8a90bb45 ("blk-mq: remove blk_mq_delay_queue()") Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-01block: split the blk-mq case from elevator_initChristoph Hellwig
There is almost no shared logic, which leads to a very confusing code flow. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Tested-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-01block: move sysfs_lock into elevator_initChristoph Hellwig
Both callers take just around so function call, so move it in. Also remove the now pointless blk_mq_sched_init wrapper. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Tested-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29blk-mq: simplify blk_mq_rq_timed_outChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29block: remove BLK_EH_HANDLEDChristoph Hellwig
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>
2018-05-29block: rename BLK_EH_NOT_HANDLED to BLK_EH_DONEChristoph Hellwig
The BLK_EH_NOT_HANDLED implies nothing happen, but very often that is not what is happening - instead the driver already completed the command. Fix the symbolic name to reflect that a little better. 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>
2018-05-29blk-mq: Remove generation seqeunceKeith Busch
This patch simplifies the timeout handling by relying on the request reference counting to ensure the iterator is operating on an inflight and truly timed out request. Since the reference counting prevents the tag from being reallocated, the block layer no longer needs to prevent drivers from completing their requests while the timeout handler is operating on it: a driver completing a request is allowed to proceed to the next state without additional syncronization with the block layer. This also removes any need for generation sequence numbers since the request lifetime is prevented from being reallocated as a new sequence while timeout handling is operating on it. To enables this a refcount is added to struct request so that request users can be sure they're operating on the same request without it changing while they're processing it. The request's tag won't be released for reuse until both the timeout handler and the completion are done with it. Signed-off-by: Keith Busch <keith.busch@intel.com> [hch: slight cleanups, added back submission side hctx lock, use cmpxchg for completions] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29blk-mq: Fix timeout and state orderKeith Busch
The block layer had been setting the state to in-flight prior to updating the timer. This is the wrong order since the timeout handler could observe the in-flight state with the older timeout, believing the request had expired when in fact it is just getting started. Signed-off-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-22blk-mq: remove wrong 'unlikely' checkhuhai
When dispatch_rq_from_ctx is called, in the vast majority of cases the ctx->rq_list is not empty. Signed-off-by: huhai <huhai@kylinos.cn> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-18blk-mq: clear hctx->dispatch_from when mappings changehuhai
When the number of hardware queues is changed, the drivers will call blk_mq_update_nr_hw_queues() to remap hardware queues. This changes the ctx mappings, but the current code doesn't clear the ->dispatch_from hint. This can result in dispatch_from pointing to a ctx that isn't mapped to the hctx anymore. Fixes: b347689ffbca ("blk-mq-sched: improve dispatching from sw queue") Signed-off-by: huhai <huhai@kylinos.cn> Reviewed-by: Ming Lei <ming.lei@redhat.com> Moved the placement of the clearing to where we clear other items pertaining to the existing mapping, added Fixes line, and reworded the commit message. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-16blk-mq: remove redundant insert case in blk_mq_make_request()huhai
We can use blk_mq_sched_insert_request() even if we don't have an IO scheduler attached, since that case will end up being exactly the same as what blk_mq_queue_io() was doing now. Signed-off-by: huhai <huhai@kylinos.cn> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-10blk-mq: don't call into depth limiting for reserved tagsJens Axboe
It's not useful, they are internal and/or error handling recovery commands. Acked-by: Paolo Valente <paolo.valente@linaro.org> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-09block: consolidate struct request timestamp fieldsOmar Sandoval
Currently, struct request has four timestamp fields: - A start time, set at get_request time, in jiffies, used for iostats - An I/O start time, set at start_request time, in ktime nanoseconds, used for blk-stats (i.e., wbt, kyber, hybrid polling) - Another start time and another I/O start time, used for cfq and bfq These can all be consolidated into one start time and one I/O start time, both in ktime nanoseconds, shaving off up to 16 bytes from struct request depending on the kernel config. Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-09block: move blk_stat_add() to __blk_mq_end_request()Omar Sandoval
We want this next to blk_account_io_done() for the next change so that we can call ktime_get() only once for both. Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-09block: get rid of struct blk_issue_statOmar Sandoval
struct blk_issue_stat squashes three things into one u64: - The time the driver started working on a request - The original size of the request (for the io.low controller) - Flags for writeback throttling It turns out that on x86_64, we have a 4 byte hole in struct request which we can fill with the non-timestamp fields from blk_issue_stat, simplifying things quite a bit. Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-09block: pass struct request instead of struct blk_issue_stat to wbtOmar Sandoval
issue_stat is going to go away, so first make writeback throttling take the containing request, update the internal wbt helpers accordingly, and change rwb->sync_cookie to be the request pointer instead of the issue_stat pointer. No functional change. Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-04-26blk-mq: fix sysfs inflight counterOmar Sandoval
When the blk-mq inflight implementation was added, /proc/diskstats was converted to use it, but /sys/block/$dev/inflight was not. Fix it by adding another helper to count in-flight requests by data direction. Fixes: f299b7c7a9de ("blk-mq: provide internal in-flight variant") Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-04-26blk-mq: count allocated but not started requests in iostats inflightOmar Sandoval
In the legacy block case, we increment the counter right after we allocate the request, not when the driver handles it. In both the legacy and blk-mq cases, part_inc_in_flight() is called from blk_account_io_start() right after we've allocated the request. blk-mq only considers requests started requests as inflight, but this is inconsistent with the legacy definition and the intention in the code. This removes the started condition and instead counts all allocated requests. Fixes: f299b7c7a9de ("blk-mq: provide internal in-flight variant") Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-04-25Revert "blk-mq: remove code for dealing with remapping queue"Ming Lei
This reverts commit 37c7c6c76d431dd7ef9c29d95f6052bd425f004c. Turns out some drivers(most are FC drivers) may not use managed IRQ affinity, and has their customized .map_queues meantime, so still keep this code for avoiding regression. Reported-by: Laurence Oberman <loberman@redhat.com> Tested-by: Laurence Oberman <loberman@redhat.com> Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Tested-by: Stefan Haberland <sth@linux.vnet.ibm.com> Cc: Ewan Milne <emilne@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-04-16blk-mq: start request gstate with gen 1Jianchao Wang
rq->gstate and rq->aborted_gstate both are zero before rqs are allocated. If we have a small timeout, when the timer fires, there could be rqs that are never allocated, and also there could be rq that has been allocated but not initialized and started. At the moment, the rq->gstate and rq->aborted_gstate both are 0, thus the blk_mq_terminate_expired will identify the rq is timed out and invoke .timeout early. For scsi, this will cause scsi_times_out to be invoked before the scsi_cmnd is not initialized, scsi_cmnd->device is still NULL at the moment, then we will get crash. Cc: Bart Van Assche <bart.vanassche@wdc.com> Cc: Tejun Heo <tj@kernel.org> Cc: Ming Lei <ming.lei@redhat.com> Cc: Martin Steigerwald <Martin@Lichtvoll.de> Cc: stable@vger.kernel.org Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-04-10blk-mq: remove code for dealing with remapping queueMing Lei
Firstly, from commit 4b855ad37194 ("blk-mq: Create hctx for each present CPU), blk-mq doesn't remap queue any more after CPU topo is changed. Secondly, set->nr_hw_queues can't be bigger than nr_cpu_ids, and now we map all possible CPUs to hw queues, so at least one CPU is mapped to each hctx. So queue mapping has became static and fixed just like percpu variable, and we don't need to handle queue remapping any more. Cc: Stefan Haberland <sth@linux.vnet.ibm.com> Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-04-10blk-mq: don't check queue mapped in __blk_mq_delay_run_hw_queue()Ming Lei
There are several reasons for removing the check: 1) blk_mq_hw_queue_mapped() returns true always now since each hctx may be mapped by one CPU at least 2) when there isn't any online CPU mapped to this hctx, there won't be any IO queued to this CPU, blk_mq_run_hw_queue() only runs queue if there is IO queued to this hctx 3) If __blk_mq_delay_run_hw_queue() is called by blk_mq_delay_run_hw_queue(), which is run from blk_mq_dispatch_rq_list() or scsi_mq_get_budget(), and the hctx to be handled has to be mapped. Cc: Stefan Haberland <sth@linux.vnet.ibm.com> Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-04-10blk-mq: remove blk_mq_delay_queue()Ming Lei
No driver uses this interface any more, so remove it. Cc: Stefan Haberland <sth@linux.vnet.ibm.com> Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>