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2021-07-28scsi: scsi_ioctl: Remove scsi_verify_blk_ioctl()Christoph Hellwig
Manually verify that the device is not a partition and the caller has admin privіleges at the beginning of the sr ioctl method and open code the trivial check for sd as well. Link: https://lore.kernel.org/r/20210724072033.1284840-11-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-07-28scsi: scsi_ioctl: Remove scsi_cmd_blk_ioctl()Christoph Hellwig
Open code scsi_cmd_blk_ioctl() in its two callers. Link: https://lore.kernel.org/r/20210724072033.1284840-10-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-07-24Merge tag 'block-5.14-2021-07-24' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: - NVMe pull request (Christoph): - tracing fix (Keith Busch) - fix multipath head refcounting (Hannes Reinecke) - Write Zeroes vs PI fix (me) - drop a bogus WARN_ON (Zhihao Cheng) - Increase max blk-cgroup policy size, now that mq-deadline uses it too (Oleksandr) * tag 'block-5.14-2021-07-24' of git://git.kernel.dk/linux-block: nvme: set the PRACT bit when using Write Zeroes with T10 PI nvme: fix nvme_setup_command metadata trace event nvme: fix refcounting imbalance when all paths are down nvme-pci: don't WARN_ON in nvme_reset_work if ctrl.state is not RESETTING block: increase BLKCG_MAX_POLS
2021-07-17block: increase BLKCG_MAX_POLSOleksandr Natalenko
After mq-deadline learned to deal with cgroups, the BLKCG_MAX_POLS value became too small for all the elevators to be registered properly. The following issue is seen: ``` calling bfq_init+0x0/0x8b @ 1 blkcg_policy_register: BLKCG_MAX_POLS too small initcall bfq_init+0x0/0x8b returned -28 after 507 usecs ``` which renders BFQ non-functional. Increase BLKCG_MAX_POLS to allow enough space for everyone. Fixes: 08a9ad8bf607 ("block/mq-deadline: Add cgroup support") Link: https://lore.kernel.org/lkml/8988303.mDXGIdCtx8@natalenko.name/ Signed-off-by: Oleksandr Natalenko <oleksandr@natalenko.name> Link: https://lore.kernel.org/r/20210717123328.945810-1-oleksandr@natalenko.name Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-09Merge tag 'block-5.14-2021-07-08' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull more block updates from Jens Axboe: "A combination of changes that ended up depending on both the driver and core branch (and/or the IDE removal), and a few late arriving fixes. In detail: - Fix io ticks wrap-around issue (Chunguang) - nvme-tcp sock locking fix (Maurizio) - s390-dasd fixes (Kees, Christoph) - blk_execute_rq polling support (Keith) - blk-cgroup RCU iteration fix (Yu) - nbd backend ID addition (Prasanna) - Partition deletion fix (Yufen) - Use blk_mq_alloc_disk for mmc, mtip32xx, ubd (Christoph) - Removal of now dead block request types due to IDE removal (Christoph) - Loop probing and control device cleanups (Christoph) - Device uevent fix (Christoph) - Misc cleanups/fixes (Tetsuo, Christoph)" * tag 'block-5.14-2021-07-08' of git://git.kernel.dk/linux-block: (34 commits) blk-cgroup: prevent rcu_sched detected stalls warnings while iterating blkgs block: fix the problem of io_ticks becoming smaller nvme-tcp: can't set sk_user_data without write_lock loop: remove unused variable in loop_set_status() block: remove the bdgrab in blk_drop_partitions block: grab a device refcount in disk_uevent s390/dasd: Avoid field over-reading memcpy() dasd: unexport dasd_set_target_state block: check disk exist before trying to add partition ubd: remove dead code in ubd_setup_common nvme: use return value from blk_execute_rq() block: return errors from blk_execute_rq() nvme: use blk_execute_rq() for passthrough commands block: support polling through blk_execute_rq block: remove REQ_OP_SCSI_{IN,OUT} block: mark blk_mq_init_queue_data static loop: rewrite loop_exit using idr_for_each_entry loop: split loop_lookup loop: don't allow deleting an unspecified loop device loop: move loop_ctl_mutex locking into loop_add ...
2021-06-30Merge tag 'for-5.14/dm-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - Various DM persistent-data library improvements and fixes that benefit both the DM thinp and cache targets. - A few small DM kcopyd efficiency improvements. - Significant zoned related block core, DM core and DM zoned target changes that culminate with adding zoned append emulation (which is required to properly fix DM crypt's zoned support). - Various DM writecache target changes that improve efficiency. Adds an optional "metadata_only" feature that only promotes bios flagged with REQ_META. But the most significant improvement is writecache's ability to pause writeback, for a confiurable time, if/when the working set is larger than the cache (and the cache is full) -- this ensures performance is no worse than the slower origin device. * tag 'for-5.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (35 commits) dm writecache: make writeback pause configurable dm writecache: pause writeback if cache full and origin being written directly dm io tracker: factor out IO tracker dm btree remove: assign new_root only when removal succeeds dm zone: fix dm_revalidate_zones() memory allocation dm ps io affinity: remove redundant continue statement dm writecache: add optional "metadata_only" parameter dm writecache: add "cleaner" and "max_age" to Documentation dm writecache: write at least 4k when committing dm writecache: flush origin device when writing and cache is full dm writecache: have ssd writeback wait if the kcopyd workqueue is busy dm writecache: use list_move instead of list_del/list_add in writecache_writeback() dm writecache: commit just one block, not a full page dm writecache: remove unused gfp_t argument from wc_add_block() dm crypt: Fix zoned block device support dm: introduce zone append emulation dm: rearrange core declarations for extended use from dm-zone.c block: introduce BIO_ZONE_WRITE_LOCKED bio flag block: introduce bio zone helpers block: improve handling of all zones reset operation ...
2021-06-30block: return errors from blk_execute_rq()Keith Busch
The synchronous blk_execute_rq() had not provided a way for its callers to know if its request was successful or not. Return the blk_status_t result of the request. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210610214437.641245-4-kbusch@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-30block: remove REQ_OP_SCSI_{IN,OUT}Christoph Hellwig
With the legacy IDE driver gone drivers now use either REQ_OP_DRV_* or REQ_OP_SCSI_*, so unify the two concepts of passthrough requests into a single one. Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-04block: introduce bio zone helpersDamien Le Moal
Introduce the helper functions bio_zone_no() and bio_zone_is_seq(). Both are the BIO counterparts of the request helpers blk_rq_zone_no() and blk_rq_zone_is_seq(), respectively returning the number of the target zone of a bio and true if the BIO target zone is sequential. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2021-06-01block: unexport blk_alloc_queueChristoph Hellwig
blk_alloc_queue is just an internal helper now, unexport it and remove it from the public header. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://lore.kernel.org/r/20210521055116.1053587-27-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-24blk-mq: Use request queue-wide tags for tagset-wide sbitmapJohn Garry
The tags used for an IO scheduler are currently per hctx. As such, when q->nr_hw_queues grows, so does the request queue total IO scheduler tag depth. This may cause problems for SCSI MQ HBAs whose total driver depth is fixed. Ming and Yanhui report higher CPU usage and lower throughput in scenarios where the fixed total driver tag depth is appreciably lower than the total scheduler tag depth: https://lore.kernel.org/linux-block/440dfcfc-1a2c-bd98-1161-cec4d78c6dfc@huawei.com/T/#mc0d6d4f95275a2743d1c8c3e4dc9ff6c9aa3a76b In that scenario, since the scheduler tag is got first, much contention is introduced since a driver tag may not be available after we have got the sched tag. Improve this scenario by introducing request queue-wide tags for when a tagset-wide sbitmap is used. The static sched requests are still allocated per hctx, as requests are initialised per hctx, as in blk_mq_init_request(..., hctx_idx, ...) -> set->ops->init_request(.., hctx_idx, ...). For simplicity of resizing the request queue sbitmap when updating the request queue depth, just init at the max possible size, so we don't need to deal with the possibly with swapping out a new sbitmap for old if we need to grow. Signed-off-by: John Garry <john.garry@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/1620907258-30910-3-git-send-email-john.garry@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-15Merge tag 'block-5.13-2021-05-14' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: - Fix for shared tag set exit (Bart) - Correct ioctl range for zoned ioctls (Damien) - Removed dead/unused function (Lin) - Fix perf regression for shared tags (Ming) - Fix out-of-bounds issue with kyber and preemption (Omar) - BFQ merge fix (Paolo) - Two error handling fixes for nbd (Sun) - Fix weight update in blk-iocost (Tejun) - NVMe pull request (Christoph): - correct the check for using the inline bio in nvmet (Chaitanya Kulkarni) - demote unsupported command warnings (Chaitanya Kulkarni) - fix corruption due to double initializing ANA state (me, Hou Pu) - reset ns->file when open fails (Daniel Wagner) - fix a NULL deref when SEND is completed with error in nvmet-rdma (Michal Kalderon) - Fix kernel-doc warning (Bart) * tag 'block-5.13-2021-05-14' of git://git.kernel.dk/linux-block: block/partitions/efi.c: Fix the efi_partition() kernel-doc header blk-mq: Swap two calls in blk_mq_exit_queue() blk-mq: plug request for shared sbitmap nvmet: use new ana_log_size instead the old one nvmet: seset ns->file when open fails nbd: share nbd_put and return by goto put_nbd nbd: Fix NULL pointer in flush_workqueue blkdev.h: remove unused codes blk_account_rq block, bfq: avoid circular stable merges blk-iocost: fix weight updates of inner active iocgs nvmet: demote fabrics cmd parse err msg to debug nvmet: use helper to remove the duplicate code nvmet: demote discovery cmd parse err msg to debug nvmet-rdma: Fix NULL deref when SEND is completed with error nvmet: fix inline bio check for passthru nvmet: fix inline bio check for bdev-ns nvme-multipath: fix double initialization of ANA state kyber: fix out of bounds access when preempted block: uapi: fix comment about block device ioctl
2021-05-12blkdev.h: remove unused codes blk_account_rqLin Feng
Last users of blk_account_rq gone with patch commit a1ce35fa49852db ("block: remove dead elevator code") and now it gets no caller, it can be safely removed. Signed-off-by: Lin Feng <linf@wangsu.com> Link: https://lore.kernel.org/r/20210512100124.173769-1-linf@wangsu.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-09Merge tag 'block-5.13-2021-05-09' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fix from Jens Axboe: "Turns out the bio max size change still has issues, so let's get it reverted for 5.13-rc1. We'll shake out the issues there and defer it to 5.14 instead" * tag 'block-5.13-2021-05-09' of git://git.kernel.dk/linux-block: Revert "bio: limit bio max size"
2021-05-08Revert "bio: limit bio max size"Jens Axboe
This reverts commit cd2c7545ae1beac3b6aae033c7f31193b3255946. Alex reports that the commit causes corruption with LUKS on ext4. Revert it for now so that this can be investigated properly. Link: https://lore.kernel.org/linux-block/1620493841.bxdq8r5haw.none@localhost/ Reported-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-07Merge tag 'block-5.13-2021-05-07' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: - dasd spelling fixes (Bhaskar) - Limit bio max size on multi-page bvecs to the hardware limit, to avoid overly large bio's (and hence latencies). Originally queued for the merge window, but needed a fix and was dropped from the initial pull (Changheun) - NVMe pull request (Christoph): - reset the bdev to ns head when failover (Daniel Wagner) - remove unsupported command noise (Keith Busch) - misc passthrough improvements (Kanchan Joshi) - fix controller ioctl through ns_head (Minwoo Im) - fix controller timeouts during reset (Tao Chiu) - rnbd fixes/cleanups (Gioh, Md, Dima) - Fix iov_iter re-expansion (yangerkun) * tag 'block-5.13-2021-05-07' of git://git.kernel.dk/linux-block: block: reexpand iov_iter after read/write nvmet: remove unsupported command noise nvme-multipath: reset bdev to ns head when failover nvme-pci: fix controller reset hang when racing with nvme_timeout nvme: move the fabrics queue ready check routines to core nvme: avoid memset for passthrough requests nvme: add nvme_get_ns helper nvme: fix controller ioctl through ns_head bio: limit bio max size RDMA/rtrs: fix uninitialized symbol 'cnt' s390: dasd: Mundane spelling fixes block/rnbd: Remove all likely and unlikely block/rnbd-clt: Check the return value of the function rtrs_clt_query block/rnbd: Fix style issues block/rnbd-clt: Change queue_depth type in rnbd_clt_session to size_t
2021-05-06include: remove pagemap.h from blkdev.hMatthew Wilcox (Oracle)
My UEK-derived config has 1030 files depending on pagemap.h before this change. Afterwards, just 326 files need to be rebuilt when I touch pagemap.h. I think blkdev.h is probably included too widely, but untangling that dependency is harder and this solves my problem. x86 allmodconfig builds, but there may be implicit include problems on other architectures. Link: https://lkml.kernel.org/r/20210309195747.283796-1-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Dan Williams <dan.j.williams@intel.com> [nvdimm] Acked-by: Jens Axboe <axboe@kernel.dk> [block] Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Coly Li <colyli@suse.de> [bcache] Acked-by: Martin K. Petersen <martin.petersen@oracle.com> [scsi] Reviewed-by: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-03bio: limit bio max sizeChangheun Lee
bio size can grow up to 4GB when muli-page bvec is enabled. but sometimes it would lead to inefficient behaviors. in case of large chunk direct I/O, - 32MB chunk read in user space - all pages for 32MB would be merged to a bio structure if the pages physical addresses are contiguous. it makes some delay to submit until merge complete. bio max size should be limited to a proper size. When 32MB chunk read with direct I/O option is coming from userspace, kernel behavior is below now in do_direct_IO() loop. it's timeline. | bio merge for 32MB. total 8,192 pages are merged. | total elapsed time is over 2ms. |------------------ ... ----------------------->| | 8,192 pages merged a bio. | at this time, first bio submit is done. | 1 bio is split to 32 read request and issue. |---------------> |---------------> |---------------> ...... |---------------> |--------------->| total 19ms elapsed to complete 32MB read done from device. | If bio max size is limited with 1MB, behavior is changed below. | bio merge for 1MB. 256 pages are merged for each bio. | total 32 bio will be made. | total elapsed time is over 2ms. it's same. | but, first bio submit timing is fast. about 100us. |--->|--->|--->|---> ... -->|--->|--->|--->|--->| | 256 pages merged a bio. | at this time, first bio submit is done. | and 1 read request is issued for 1 bio. |---------------> |---------------> |---------------> ...... |---------------> |--------------->| total 17ms elapsed to complete 32MB read done from device. | As a result, read request issue timing is faster if bio max size is limited. Current kernel behavior with multipage bvec, super large bio can be created. And it lead to delay first I/O request issue. Signed-off-by: Changheun Lee <nanich.lee@samsung.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20210503095203.29076-1-nanich.lee@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-28Merge tag 'for-5.13/drivers-2021-04-27' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block driver updates from Jens Axboe: - MD changes via Song: - raid5 POWER fix - raid1 failure fix - UAF fix for md cluster - mddev_find_or_alloc() clean up - Fix NULL pointer deref with external bitmap - Performance improvement for raid10 discard requests - Fix missing information of /proc/mdstat - rsxx const qualifier removal (Arnd) - Expose allocated brd pages (Calvin) - rnbd via Gioh Kim: - Change maintainer - Change domain address of maintainers' email - Add polling IO mode and document update - Fix memory leak and some bug detected by static code analysis tools - Code refactoring - Series of floppy cleanups/fixes (Denis) - s390 dasd fixes (Julian) - kerneldoc fixes (Lee) - null_blk double free (Lv) - null_blk virtual boundary addition (Max) - Remove xsysace driver (Michal) - umem driver removal (Davidlohr) - ataflop fixes (Dan) - Revalidate disk removal (Christoph) - Bounce buffer cleanups (Christoph) - Mark lightnvm as deprecated (Christoph) - mtip32xx init cleanups (Shixin) - Various fixes (Tian, Gustavo, Coly, Yang, Zhang, Zhiqiang) * tag 'for-5.13/drivers-2021-04-27' of git://git.kernel.dk/linux-block: (143 commits) async_xor: increase src_offs when dropping destination page drivers/block/null_blk/main: Fix a double free in null_init. md/raid1: properly indicate failure when ending a failed write request md-cluster: fix use-after-free issue when removing rdev nvme: introduce generic per-namespace chardev nvme: cleanup nvme_configure_apst nvme: do not try to reconfigure APST when the controller is not live nvme: add 'kato' sysfs attribute nvme: sanitize KATO setting nvmet: avoid queuing keep-alive timer if it is disabled brd: expose number of allocated pages in debugfs ataflop: fix off by one in ataflop_probe() ataflop: potential out of bounds in do_format() drbd: Fix fall-through warnings for Clang block/rnbd: Use strscpy instead of strlcpy block/rnbd-clt-sysfs: Remove copy buffer overlap in rnbd_clt_get_path_name block/rnbd-clt: Remove max_segment_size block/rnbd-clt: Generate kobject_uevent when the rnbd device state changes block/rnbd-srv: Remove unused arguments of rnbd_srv_rdma_ev Documentation/ABI/rnbd-clt: Add description for nr_poll_queues ...
2021-04-28Merge tag 'for-5.13/block-2021-04-27' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block updates from Jens Axboe: "Pretty quiet round this time, which is nice. In detail: - Series revamping bounce buffer support (Christoph) - Dead code removal (Christoph, Bart) - Partition iteration revamp, now using xarray (Christoph) - Passthrough request scheduler improvements (Lin) - Series of BFQ improvements (Paolo) - Fix ioprio task iteration (Peter) - Various little tweaks and fixes (Tejun, Saravanan, Bhaskar, Max, Nikolay)" * tag 'for-5.13/block-2021-04-27' of git://git.kernel.dk/linux-block: (41 commits) blk-iocost: don't ignore vrate_min on QD contention blk-mq: Fix spurious debugfs directory creation during initialization bfq/mq-deadline: remove redundant check for passthrough request blk-mq: bypass IO scheduler's limit_depth for passthrough request block: Remove an obsolete comment from sg_io() block: move bio_list_copy_data to pktcdvd block: remove zero_fill_bio_iter block: add queue_to_disk() to get gendisk from request_queue block: remove an incorrect check from blk_rq_append_bio block: initialize ret in bdev_disk_changed block: Fix sys_ioprio_set(.which=IOPRIO_WHO_PGRP) task iteration block: remove disk_part_iter block: simplify diskstats_show block: simplify show_partition block: simplify printk_all_partitions block: simplify partition_overlaps block: simplify partition removal block: take bd_mutex around delete_partitions in del_gendisk block: refactor blk_drop_partitions block: move more syncing and invalidation to delete_partition ...
2021-04-16blk-mq: bypass IO scheduler's limit_depth for passthrough requestLin Feng
Commit 01e99aeca39796003 ("blk-mq: insert passthrough request into hctx->dispatch directly") gives high priority to passthrough requests and bypass underlying IO scheduler. But as we allocate tag for such request it still runs io-scheduler's callback limit_depth, while we really want is to give full sbitmap-depth capabity to such request for acquiring available tag. blktrace shows PC requests(dmraid -s -c -i) hit bfq's limit_depth: 8,0 2 0 0.000000000 39952 1,0 m N bfq [bfq_limit_depth] wr_busy 0 sync 0 depth 8 8,0 2 1 0.000008134 39952 D R 4 [dmraid] 8,0 2 2 0.000021538 24 C R [0] 8,0 2 0 0.000035442 39952 1,0 m N bfq [bfq_limit_depth] wr_busy 0 sync 0 depth 8 8,0 2 3 0.000038813 39952 D R 24 [dmraid] 8,0 2 4 0.000044356 24 C R [0] This patch introduce a new wrapper to make code not that ugly. Signed-off-by: Lin Feng <linf@wangsu.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210415033920.213963-1-linf@wangsu.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-12block: add queue_to_disk() to get gendisk from request_queueJeffle Xu
Sometimes we need to get the corresponding gendisk from request_queue. It is preferred that block drivers store private data in gendisk->private_data rather than request_queue->queuedata, e.g. see: commit c4a59c4e5db3 ("dm: stop using ->queuedata"). So if only request_queue is given, we need to get its corresponding gendisk to get the private data stored in that gendisk. Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-06block: stop calling blk_queue_bounce for passthrough requestsChristoph Hellwig
Instead of overloading the passthrough fast path with the deprecated block layer bounce buffering let the users that combine an old undermaintained driver with a highmem system pay the price by always falling back to copies in that case. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20210331073001.46776-9-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-06block: refactor the bounce buffering codeChristoph Hellwig
Get rid of all the PFN arithmetics and just use an enum for the two remaining options, and use PageHighMem for the actual bounce decision. Add a fast path to entirely avoid the call for the common case of a queue not using the legacy bouncing code. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20210331073001.46776-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-06block: remove BLK_BOUNCE_ISA supportChristoph Hellwig
Remove the BLK_BOUNCE_ISA support now that all users are gone. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20210331073001.46776-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-02block: remove the unused RQF_ALLOCED flagChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-29block: remove the revalidate_disk methodChristoph Hellwig
No implementations left. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210308074550.422714-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-01block: Drop leftover references to RQF_SORTEDJean Delvare
Commit a1ce35fa49852db60fc6e268038530be533c5b15 ("block: remove dead elevator code") removed all users of RQF_SORTED. However it is still defined, and there is one reference left to it (which in effect is dead code). Clear it all up. Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Ming Lei <ming.lei@redhat.com> Cc: Omar Sandoval <osandov@fb.com> Cc: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-28Merge tag 'block-5.12-2021-02-27' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull more block updates from Jens Axboe: "A few stragglers (and one due to me missing it originally), and fixes for changes in this merge window mostly. In particular: - blktrace cleanups (Chaitanya, Greg) - Kill dead blk_pm_* functions (Bart) - Fixes for the bio alloc changes (Christoph) - Fix for the partition changes (Christoph, Ming) - Fix for turning off iopoll with polled IO inflight (Jeffle) - nbd disconnect fix (Josef) - loop fsync error fix (Mauricio) - kyber update depth fix (Yang) - max_sectors alignment fix (Mikulas) - Add bio_max_segs helper (Matthew)" * tag 'block-5.12-2021-02-27' of git://git.kernel.dk/linux-block: (21 commits) block: Add bio_max_segs blktrace: fix documentation for blk_fill_rw() block: memory allocations in bounce_clone_bio must not fail block: remove the gfp_mask argument to bounce_clone_bio block: fix bounce_clone_bio for passthrough bios block-crypto-fallback: use a bio_set for splitting bios block: fix logging on capacity change blk-settings: align max_sectors on "logical_block_size" boundary block: reopen the device in blkdev_reread_part block: don't skip empty device in in disk_uevent blktrace: remove debugfs file dentries from struct blk_trace nbd: handle device refs for DESTROY_ON_DISCONNECT properly kyber: introduce kyber_depth_updated() loop: fix I/O error on fsync() in detached loop devices block: fix potential IO hang when turning off io_poll block: get rid of the trace rq insert wrapper blktrace: fix blk_rq_merge documentation blktrace: fix blk_rq_issue documentation blktrace: add blk_fill_rwbs documentation comment block: remove superfluous param in blk_fill_rwbs() ...
2021-02-22Merge tag 'for-5.12/block-ipi-2021-02-21' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block IPI updates from Jens Axboe: "Avoid IRQ locking for the block IPI handling (Sebastian Andrzej Siewior)" * tag 'for-5.12/block-ipi-2021-02-21' of git://git.kernel.dk/linux-block: blk-mq: Use llist_head for blk_cpu_done blk-mq: Always complete remote completions requests in softirq smp: Process pending softirqs in flush_smp_call_function_from_idle()
2021-02-22block: Remove unused blk_pm_*() function definitionsBart Van Assche
Commit a1ce35fa4985 ("block: remove dead elevator code") removed the last callers of blk_pm_requeue_request(), blk_pm_add_request() and blk_pm_put_request(). Hence remove the definitions of these functions. Removing these functions removes all users of the struct request nr_pending member. Hence also remove 'nr_pending'. Note: 'nr_pending' is no longer used since commit 7cedffec8e75 ("block: Make blk_get_request() block for non-PM requests while suspended"). Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-12blk-mq: Use llist_head for blk_cpu_doneSebastian Andrzej Siewior
With llist_head it is possible to avoid the locking (the irq-off region) when items are added. This makes it possible to add items on a remote CPU without additional locking. llist_add() returns true if the list was previously empty. This can be used to invoke the SMP function call / raise sofirq only if the first item was added (otherwise it is already pending). This simplifies the code a little and reduces the IRQ-off regions. blk_mq_raise_softirq() needs a preempt-disable section to ensure the request is enqueued on the same CPU as the softirq is raised. Some callers (USB-storage) invoke this path in preemptible context. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Daniel Wagner <dwagner@suse.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-02-10block: introduce zone_write_granularity limitDamien Le Moal
Per ZBC and ZAC specifications, host-managed SMR hard-disks mandate that all writes into sequential write required zones be aligned to the device physical block size. However, NVMe ZNS does not have this constraint and allows write operations into sequential zones to be aligned to the device logical block size. This inconsistency does not help with software portability across device types. To solve this, introduce the zone_write_granularity queue limit to indicate the alignment constraint, in bytes, of write operations into zones of a zoned block device. This new limit is exported as a read-only sysfs queue attribute and the helper blk_queue_zone_write_granularity() introduced for drivers to set this limit. The function blk_queue_set_zoned() is modified to set this new limit to the device logical block size by default. NVMe ZNS devices as well as zoned nullb devices use this default value as is. The scsi disk driver is modified to execute the blk_queue_zone_write_granularity() helper to set the zone write granularity of host-managed SMR disks to the disk physical block size. The accessor functions queue_zone_write_granularity() and bdev_zone_write_granularity() are also introduced. Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@edc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-27block: use an on-stack bio in blkdev_issue_flushChristoph Hellwig
There is no point in allocating memory for a synchronous flush. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Acked-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-26block: unexport truncate_bdev_rangeChristoph Hellwig
truncate_bdev_range is only used in always built-in block layer code, so remove the export and the !CONFIG_BLOCK stub. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24block: remove unnecessary argument from blk_execute_rqGuoqing Jiang
We can remove 'q' from blk_execute_rq as well after the previous change in blk_execute_rq_nowait. And more importantly it never really was needed to start with given that we can trivial derive it from struct request. Cc: linux-scsi@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Cc: linux-ide@vger.kernel.org Cc: linux-mmc@vger.kernel.org Cc: linux-nvme@lists.infradead.org Cc: linux-nfs@vger.kernel.org Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24block: remove unnecessary argument from blk_execute_rq_nowaitGuoqing Jiang
The 'q' is not used since commit a1ce35fa4985 ("block: remove dead elevator code"), also update the comment of the function. And more importantly it never really was needed to start with given that we can trivial derive it from struct request. Cc: target-devel@vger.kernel.org Cc: linux-scsi@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Cc: linux-ide@vger.kernel.org Cc: linux-mmc@vger.kernel.org Cc: linux-nvme@lists.infradead.org Cc: linux-nfs@vger.kernel.org Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24block: use ->bi_bdev for bio based I/O accountingChristoph Hellwig
Rework the I/O accounting for bio based drivers to use ->bi_bdev. This means all drivers can now simply use bio_start_io_acct to start accounting, and it will take partitions into account automatically. To end I/O account either bio_end_io_acct can be used if the driver never remaps I/O to a different device, or bio_end_io_acct_remapped if the driver did remap the I/O. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-24block: store a block_device pointer in struct bioChristoph Hellwig
Replace the gendisk pointer in struct bio with a pointer to the newly improved struct block device. From that the gendisk can be trivially accessed with an extra indirection, but it also allows to directly look up all information related to partition remapping. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-01Merge tag 'scsi-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi Pull SCSI fixes from James Bottomley: "This is a load of driver fixes (12 ufs, 1 mpt3sas, 1 cxgbi). The big core two fixes are for power management ("block: Do not accept any requests while suspended" and "block: Fix a race in the runtime power management code") which finally sorts out the resume problems we've occasionally been having. To make the resume fix, there are seven necessary precursors which effectively renames REQ_PREEMPT to REQ_PM, so every "special" request in block is automatically a power management exempt one. All of the non-PM preempt cases are removed except for the one in the SCSI Parallel Interface (spi) domain validation which is a genuine case where we have to run requests at high priority to validate the bus so this becomes an autopm get/put protected request" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (22 commits) scsi: cxgb4i: Fix TLS dependency scsi: ufs: Un-inline ufshcd_vops_device_reset function scsi: ufs: Re-enable WriteBooster after device reset scsi: ufs-mediatek: Use correct path to fix compile error scsi: mpt3sas: Signedness bug in _base_get_diag_triggers() scsi: block: Do not accept any requests while suspended scsi: block: Remove RQF_PREEMPT and BLK_MQ_REQ_PREEMPT scsi: core: Only process PM requests if rpm_status != RPM_ACTIVE scsi: scsi_transport_spi: Set RQF_PM for domain validation commands scsi: ide: Mark power management requests with RQF_PM instead of RQF_PREEMPT scsi: ide: Do not set the RQF_PREEMPT flag for sense requests scsi: block: Introduce BLK_MQ_REQ_PM scsi: block: Fix a race in the runtime power management code scsi: ufs-pci: Enable UFSHCD_CAP_RPM_AUTOSUSPEND for Intel controllers scsi: ufs-pci: Fix recovery from hibernate exit errors for Intel controllers scsi: ufs-pci: Ensure UFS device is in PowerDown mode for suspend-to-disk ->poweroff() scsi: ufs-pci: Fix restore from S4 for Intel controllers scsi: ufs-mediatek: Keep VCC always-on for specific devices scsi: ufs: Allow regulators being always-on scsi: ufs: Clear UAC for RPMB after ufshcd resets ...
2020-12-16Merge tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block updates from Jens Axboe: "Another series of killing more code than what is being added, again thanks to Christoph's relentless cleanups and tech debt tackling. This contains: - blk-iocost improvements (Baolin Wang) - part0 iostat fix (Jeffle Xu) - Disable iopoll for split bios (Jeffle Xu) - block tracepoint cleanups (Christoph Hellwig) - Merging of struct block_device and hd_struct (Christoph Hellwig) - Rework/cleanup of how block device sizes are updated (Christoph Hellwig) - Simplification of gendisk lookup and removal of block device aliasing (Christoph Hellwig) - Block device ioctl cleanups (Christoph Hellwig) - Removal of bdget()/blkdev_get() as exported API (Christoph Hellwig) - Disk change rework, avoid ->revalidate_disk() (Christoph Hellwig) - sbitmap improvements (Pavel Begunkov) - Hybrid polling fix (Pavel Begunkov) - bvec iteration improvements (Pavel Begunkov) - Zone revalidation fixes (Damien Le Moal) - blk-throttle limit fix (Yu Kuai) - Various little fixes" * tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block: (126 commits) blk-mq: fix msec comment from micro to milli seconds blk-mq: update arg in comment of blk_mq_map_queue blk-mq: add helper allocating tagset->tags Revert "block: Fix a lockdep complaint triggered by request queue flushing" nvme-loop: use blk_mq_hctx_set_fq_lock_class to set loop's lock class blk-mq: add new API of blk_mq_hctx_set_fq_lock_class block: disable iopoll for split bio block: Improve blk_revalidate_disk_zones() checks sbitmap: simplify wrap check sbitmap: replace CAS with atomic and sbitmap: remove swap_lock sbitmap: optimise sbitmap_deferred_clear() blk-mq: skip hybrid polling if iopoll doesn't spin blk-iocost: Factor out the base vrate change into a separate function blk-iocost: Factor out the active iocgs' state check into a separate function blk-iocost: Move the usage ratio calculation to the correct place blk-iocost: Remove unnecessary advance declaration blk-iocost: Fix some typos in comments blktrace: fix up a kerneldoc comment block: remove the request_queue to argument request based tracepoints ...
2020-12-09scsi: block: Do not accept any requests while suspendedAlan Stern
blk_queue_enter() accepts BLK_MQ_REQ_PM requests independent of the runtime power management state. Now that SCSI domain validation no longer depends on this behavior, modify the behavior of blk_queue_enter() as follows: - Do not accept any requests while suspended. - Only process power management requests while suspending or resuming. Submitting BLK_MQ_REQ_PM requests to a device that is runtime suspended causes runtime-suspended devices not to resume as they should. The request which should cause a runtime resume instead gets issued directly, without resuming the device first. Of course the device can't handle it properly, the I/O fails, and the device remains suspended. The problem is fixed by checking that the queue's runtime-PM status isn't RPM_SUSPENDED before allowing a request to be issued, and queuing a runtime-resume request if it is. In particular, the inline blk_pm_request_resume() routine is renamed blk_pm_resume_queue() and the code is unified by merging the surrounding checks into the routine. If the queue isn't set up for runtime PM, or there currently is no restriction on allowed requests, the request is allowed. Likewise if the BLK_MQ_REQ_PM flag is set and the status isn't RPM_SUSPENDED. Otherwise a runtime resume is queued and the request is blocked until conditions are more suitable. [ bvanassche: modified commit message and removed Cc: stable because without the previous patches from this series this patch would break parallel SCSI domain validation + introduced queue_rpm_status() ] Link: https://lore.kernel.org/r/20201209052951.16136-9-bvanassche@acm.org Cc: Jens Axboe <axboe@kernel.dk> Cc: Christoph Hellwig <hch@lst.de> Cc: Hannes Reinecke <hare@suse.de> Cc: Can Guo <cang@codeaurora.org> Cc: Stanley Chu <stanley.chu@mediatek.com> Cc: Ming Lei <ming.lei@redhat.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reported-and-tested-by: Martin Kepplinger <martin.kepplinger@puri.sm> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Can Guo <cang@codeaurora.org> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-12-09scsi: block: Remove RQF_PREEMPT and BLK_MQ_REQ_PREEMPTBart Van Assche
Remove flag RQF_PREEMPT and BLK_MQ_REQ_PREEMPT since these are no longer used by any kernel code. Link: https://lore.kernel.org/r/20201209052951.16136-8-bvanassche@acm.org Cc: Can Guo <cang@codeaurora.org> Cc: Stanley Chu <stanley.chu@mediatek.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Ming Lei <ming.lei@redhat.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Martin Kepplinger <martin.kepplinger@puri.sm> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Can Guo <cang@codeaurora.org> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-12-04block: fix incorrect branching in blk_max_size_offset()Mike Snitzer
If non-zero 'chunk_sectors' is passed in to blk_max_size_offset() that override will be incorrectly ignored. Old blk_max_size_offset() branching, prior to commit 3ee16db390b4, must be used only if passed 'chunk_sectors' override is zero. Fixes: 3ee16db390b4 ("dm: fix IO splitting") Cc: stable@vger.kernel.org # 5.9 Reported-by: John Dorminy <jdorminy@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-12-04dm: fix IO splittingMike Snitzer
Commit 882ec4e609c1 ("dm table: stack 'chunk_sectors' limit to account for target-specific splitting") caused a couple regressions: 1) Using lcm_not_zero() when stacking chunk_sectors was a bug because chunk_sectors must reflect the most limited of all devices in the IO stack. 2) DM targets that set max_io_len but that do _not_ provide an .iterate_devices method no longer had there IO split properly. And commit 5091cdec56fa ("dm: change max_io_len() to use blk_max_size_offset()") also caused a regression where DM no longer supported varied (per target) IO splitting. The implication being the potential for severely reduced performance for IO stacks that use a DM target like dm-cache to hide performance limitations of a slower device (e.g. one that requires 4K IO splitting). Coming full circle: Fix all these issues by discontinuing stacking chunk_sectors up using ti->max_io_len in dm_calculate_queue_limits(), add optional chunk_sectors override argument to blk_max_size_offset() and update DM's max_io_len() to pass ti->max_io_len to its blk_max_size_offset() call. Passing in an optional chunk_sectors override to blk_max_size_offset() allows for code reuse of block's centralized calculation for max IO size based on provided offset and split boundary. Fixes: 882ec4e609c1 ("dm table: stack 'chunk_sectors' limit to account for target-specific splitting") Fixes: 5091cdec56fa ("dm: change max_io_len() to use blk_max_size_offset()") Cc: stable@vger.kernel.org Reported-by: John Dorminy <jdorminy@redhat.com> Reported-by: Bruce Johnston <bjohnsto@redhat.com> Reported-by: Kirill Tkhai <ktkhai@virtuozzo.com> Reviewed-by: John Dorminy <jdorminy@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Reviewed-by: Jens Axboe <axboe@kernel.dk>
2020-12-01block: merge struct block_device and struct hd_structChristoph Hellwig
Instead of having two structures that represent each block device with different life time rules, merge them into a single one. This also greatly simplifies the reference counting rules, as we can use the inode reference count as the main reference count for the new struct block_device, with the device model reference front ending it for device model interaction. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01block: switch partition lookup to use struct block_deviceChristoph Hellwig
Use struct block_device to lookup partitions on a disk. This removes all usage of struct hd_struct from the I/O path. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Coly Li <colyli@suse.de> [bcache] Acked-by: Chao Yu <yuchao0@huawei.com> [f2fs] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01block: move the start_sect field to struct block_deviceChristoph Hellwig
Move the start_sect field to struct block_device in preparation of killing struct hd_struct. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01block: simplify the block device claiming interfaceChristoph Hellwig
Stop passing the whole device as a separate argument given that it can be trivially deducted and cleanup the !holder debug check. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-01block: simplify bdev/disk lookup in blkdev_getChristoph Hellwig
To simplify block device lookup and a few other upcoming areas, make sure that we always have a struct block_device available for each disk and each partition, and only find existing block devices in bdget. The only downside of this is that each device and partition uses a little more memory. The upside will be that a lot of code can be simplified. With that all we need to look up the block device is to lookup the inode and do a few sanity checks on the gendisk, instead of the separate lookup for the gendisk. For blk-cgroup which wants to access a gendisk without opening it, a new blkdev_{get,put}_no_open low-level interface is added to replace the previous get_gendisk use. Note that the change to look up block device directly instead of the two step lookup using struct gendisk causes a subtile change in behavior: accessing a non-existing partition on an existing block device can now cause a call to request_module. That call is harmless, and in practice no recent system will access these nodes as they aren't created by udev and static /dev/ setups are unusual. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>