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* block: move fs/block_dev.c to block/bdev.cChristoph Hellwig2021-09-071-1058/+0
| | | | | | | | Move it together with the rest of the block layer. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210907141303.1371844-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: split out operations on block special filesChristoph Hellwig2021-09-071-637/+0
| | | | | | | | | | Add a new block/fops.c for all the file and address_space operations that provide the block special file support. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210907141303.1371844-2-hch@lst.de [axboe: correct trailing whitespace while at it] Signed-off-by: Jens Axboe <axboe@kernel.dk>
* Merge tag 'io_uring-bio-cache.5-2021-08-30' of git://git.kernel.dk/linux-blockLinus Torvalds2021-08-311-2/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull support for struct bio recycling from Jens Axboe: "This adds bio recycling support for polled IO, allowing quick reuse of a bio for high IOPS scenarios via a percpu bio_set list. It's good for almost a 10% improvement in performance, bumping our per-core IO limit from ~3.2M IOPS to ~3.5M IOPS" * tag 'io_uring-bio-cache.5-2021-08-30' of git://git.kernel.dk/linux-block: bio: improve kerneldoc documentation for bio_alloc_kiocb() block: provide bio_clear_hipri() helper block: use the percpu bio cache in __blkdev_direct_IO io_uring: enable use of bio alloc cache block: clear BIO_PERCPU_CACHE flag if polling isn't supported bio: add allocation cache abstraction fs: add kiocb alloc cache flag bio: optimize initialization of a bio
| * block: use the percpu bio cache in __blkdev_direct_IOChristoph Hellwig2021-08-231-2/+4
| | | | | | | | | | | | | | | | Use bio_alloc_kiocb to dip into the percpu cache of bios when the caller asks for it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: mark blkdev_fsync staticChristoph Hellwig2021-08-241-2/+2
| | | | | | | | | | | | | | | | | | blkdev_fsync is only used inside of block_dev.c since the removal of the raw drіver. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210824151823.1575100-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: ensure the bdi is freed after inode_detach_wbChristoph Hellwig2021-08-161-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | inode_detach_wb references the "main" bdi of the inode. With the recent change to move the bdi from the request_queue to the gendisk this causes a guaranteed use after free when using certain cgroup configurations. The big itself is older through as any non-default inode reference (e.g. an open file descriptor) could have injected this use after free even before that. Fixes: 52ebea749aae ("writeback: make backing_dev_info host cgroup-specific bdi_writebacks") Reported-by: Qian Cai <quic_qiancai@quicinc.com> Reported-by: syzbot <syzbot+1fb38bb7d3ce0fa3e1c4@syzkaller.appspotmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210816122614.601358-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: free the extended dev_t minor laterChristoph Hellwig2021-08-161-0/+5
| | | | | | | | | | | | | | | | | | | | The dev_t is used as the inode hash, so we should only released it once then block device inode is gone from the inode cache. Move it to bdev_free_inode to ensure that. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210816122614.601358-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: remove GENHD_FL_UPChristoph Hellwig2021-08-121-1/+1
| | | | | | | | | | | | | | | | | | Just check inode_unhashed on the whole device bdev inode instead, and provide a helper to check for that information. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210809064028.1198327-9-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: remove the bd_bdi in struct block_deviceChristoph Hellwig2021-08-091-12/+1
| | | | | | | | | | | | | | | | | | | | Just retrieve the bdi from the disk. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: move the bdi from the request_queue to the gendiskChristoph Hellwig2021-08-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | The backing device information only makes sense for file system I/O, and thus belongs into the gendisk and not the lower level request_queue structure. Move it there. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20210809141744.1203023-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: look up holders by bdevChristoph Hellwig2021-08-091-3/+0
| | | | | | | | | | | | | | | | | | Invert they way the holder relations are tracked. This very slightly reduces the memory overhead for partitioned devices. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210804094147.459763-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: make the block holder code optionalChristoph Hellwig2021-08-091-143/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the block holder code into a separate file as it is not in any way related to the other block_dev.c code, and add a new selectable config option for it so that we don't have to build it without any remapped drivers selected. The Kconfig symbol contains a _DEPRECATED suffix to match the comments added in commit 49731baa41df ("block: restore multiple bd_link_disk_holder() support"). Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20210804094147.459763-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: remove bdputChristoph Hellwig2021-08-021-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | Now that we've stopped using inode references for anything meaninful in the block layer get rid of the helper to put it and just open code the call to iput on the block_device inode. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com> Link: https://lore.kernel.org/r/20210722075402.983367-10-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: remove bdgrabChristoph Hellwig2021-08-021-15/+0
| | | | | | | | | | | | | | | | | | | | All callers are gone, and no one should grab a pure inode reference to a block device anymore. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Link: https://lore.kernel.org/r/20210722075402.983367-9-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: change the refcounting for partitionsChristoph Hellwig2021-08-021-37/+23
| | | | | | | | | | | | | | | | | | | | | | Instead of acquiring an inode reference on open make sure partitions always hold device model references to the disk while alive, and switch open to grab only a device model reference to the opened block device. If that is a partition the disk reference is transitively held by the partition already. Link: https://lore.kernel.org/r/20210722075402.983367-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: unhash the whole device inode earlierChristoph Hellwig2021-08-021-1/+1
|/ | | | | | | | | | | Unhash the whole device inode early in del_gendisk. This allows to remove the first GENHD_FL_UP check in the open path as we simply won't find a just removed inode. The second non-racy check after taking open_mutex is still kept. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210722075402.983367-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* Merge tag 'block-5.14-2021-07-30' of git://git.kernel.dk/linux-blockLinus Torvalds2021-07-301-0/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block fixes from Jens Axboe: - gendisk freeing fix (Christoph) - blk-iocost wake ordering fix (Tejun) - tag allocation error handling fix (John) - loop locking fix. While this isn't the prettiest fix in the world, nobody has any good alternatives for 5.14. Something to likely revisit for 5.15. (Tetsuo) * tag 'block-5.14-2021-07-30' of git://git.kernel.dk/linux-block: block: delay freeing the gendisk blk-iocost: fix operation ordering in iocg_wake_fn() blk-mq-sched: Fix blk_mq_sched_alloc_tags() error handling loop: reintroduce global lock for safe loop_validate_file() traversal
| * block: delay freeing the gendiskChristoph Hellwig2021-07-281-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | blkdev_get_no_open acquires a reference to the block_device through the block device inode and then tries to acquire a device model reference to the gendisk. But at this point the disk migh already be freed (although the race is free). Fix this by only freeing the gendisk from the whole device bdevs ->free_inode callback as well. Fixes: 22ae8ce8b892 ("block: simplify bdev/disk lookup in blkdev_get") Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210722075402.983367-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | Merge tag 'char-misc-5.14-rc1' of ↵Linus Torvalds2021-07-051-4/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char / misc driver updates from Greg KH: "Here is the big set of char / misc and other driver subsystem updates for 5.14-rc1. Included in here are: - habanalabs driver updates - fsl-mc driver updates - comedi driver updates - fpga driver updates - extcon driver updates - interconnect driver updates - mei driver updates - nvmem driver updates - phy driver updates - pnp driver updates - soundwire driver updates - lots of other tiny driver updates for char and misc drivers This is looking more and more like the "various driver subsystems mushed together" tree... All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (292 commits) mcb: Use DEFINE_RES_MEM() helper macro and fix the end address PNP: moved EXPORT_SYMBOL so that it immediately followed its function/variable bus: mhi: pci-generic: Add missing 'pci_disable_pcie_error_reporting()' calls bus: mhi: Wait for M2 state during system resume bus: mhi: core: Fix power down latency intel_th: Wait until port is in reset before programming it intel_th: msu: Make contiguous buffers uncached intel_th: Remove an unused exit point from intel_th_remove() stm class: Spelling fix nitro_enclaves: Set Bus Master for the NE PCI device misc: ibmasm: Modify matricies to matrices misc: vmw_vmci: return the correct errno code siox: Simplify error handling via dev_err_probe() fpga: machxo2-spi: Address warning about unused variable lkdtm/heap: Add init_on_alloc tests selftests/lkdtm: Enable various testable CONFIGs lkdtm: Add CONFIG hints in errors where possible lkdtm: Enable DOUBLE_FAULT on all architectures lkdtm/heap: Add vmalloc linear overflow test lkdtm/bugs: XFAIL UNALIGNED_LOAD_STORE_WRITE ...
| * | remove the raw driverChristoph Hellwig2021-06-041-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The raw driver used to provide direct unbuffered access to block devices before O_DIRECT was invented. It has been obsolete for more than a decade. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/lkml/Pine.LNX.4.64.0703180754060.6605@CPE00045a9c397f-CM001225dbafb6/ Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210531072526.97052-1-hch@lst.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | | Merge tag 'ext4_for_linus' of ↵Linus Torvalds2021-07-011-15/+0
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull ext4 updates from Ted Ts'o: "In addition to bug fixes and cleanups, there are two new features for ext4 in 5.14: - Allow applications to poll on changes to /sys/fs/ext4/*/errors_count - Add the ioctl EXT4_IOC_CHECKPOINT which allows the journal to be checkpointed, truncated and discarded or zero'ed" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (32 commits) jbd2: export jbd2_journal_[un]register_shrinker() ext4: notify sysfs on errors_count value change fs: remove bdev_try_to_free_page callback ext4: remove bdev_try_to_free_page() callback jbd2: simplify journal_clean_one_cp_list() jbd2,ext4: add a shrinker to release checkpointed buffers jbd2: remove redundant buffer io error checks jbd2: don't abort the journal when freeing buffers jbd2: ensure abort the journal if detect IO error when writing original buffer back jbd2: remove the out label in __jbd2_journal_remove_checkpoint() ext4: no need to verify new add extent block jbd2: clean up misleading comments for jbd2_fc_release_bufs ext4: add check to prevent attempting to resize an fs with sparse_super2 ext4: consolidate checks for resize of bigalloc into ext4_resize_begin ext4: remove duplicate definition of ext4_xattr_ibody_inline_set() ext4: fsmap: fix the block/inode bitmap comment ext4: fix comment for s_hash_unsigned ext4: use local variable ei instead of EXT4_I() macro ext4: fix avefreec in find_group_orlov ext4: correct the cache_nr in tracepoint ext4_es_shrink_exit ...
| * | fs: remove bdev_try_to_free_page callbackZhang Yi2021-06-241-15/+0
| |/ | | | | | | | | | | | | | | | | | | | | After remove the unique user of sop->bdev_try_to_free_page() callback, we could remove the callback and the corresponding blkdev_releasepage() at all. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20210610112440.3438139-9-yi.zhang@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
* | Merge tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-blockLinus Torvalds2021-06-301-152/+92
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull core block updates from Jens Axboe: - disk events cleanup (Christoph) - gendisk and request queue allocation simplifications (Christoph) - bdev_disk_changed cleanups (Christoph) - IO priority improvements (Bart) - Chained bio completion trace fix (Edward) - blk-wbt fixes (Jan) - blk-wbt enable/disable fix (Zhang) - Scheduler dispatch improvements (Jan, Ming) - Shared tagset scheduler improvements (John) - BFQ updates (Paolo, Luca, Pietro) - BFQ lock inversion fix (Jan) - Documentation improvements (Kir) - CLONE_IO block cgroup fix (Tejun) - Remove of ancient and deprecated block dump feature (zhangyi) - Discard merge fix (Ming) - Misc fixes or followup fixes (Colin, Damien, Dan, Long, Max, Thomas, Yang) * tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-block: (129 commits) block: fix discard request merge block/mq-deadline: Remove a WARN_ON_ONCE() call blk-mq: update hctx->dispatch_busy in case of real scheduler blk: Fix lock inversion between ioc lock and bfqd lock bfq: Remove merged request already in bfq_requests_merged() block: pass a gendisk to bdev_disk_changed block: move bdev_disk_changed block: add the events* attributes to disk_attrs block: move the disk events code to a separate file block: fix trace completion for chained bio block/partitions/msdos: Fix typo inidicator -> indicator block, bfq: reset waker pointer with shared queues block, bfq: check waker only for queues with no in-flight I/O block, bfq: avoid delayed merge of async queues block, bfq: boost throughput by extending queue-merging times block, bfq: consider also creation time in delayed stable merge block, bfq: fix delayed stable merge check block, bfq: let also stably merged queues enjoy weight raising blk-wbt: make sure throttle is enabled properly blk-wbt: introduce a new disable state to prevent false positive by rwb_enabled() ...
| * | block: pass a gendisk to bdev_disk_changedChristoph Hellwig2021-06-241-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | bdev_disk_changed can only operate on whole devices. Make that clear by passing a gendisk instead of the struct block_device. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210624123240.441814-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: move bdev_disk_changedChristoph Hellwig2021-06-241-53/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | Move bdev_disk_changed to block/partitions/core.c, together with the rest of the partition scanning code. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210624123240.441814-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: move bd_part_count to struct gendiskChristoph Hellwig2021-06-011-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The bd_part_count value only makes sense for whole devices, so move it to struct gendisk and give it a more descriptive name. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210525061301.2242282-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: split __blkdev_putChristoph Hellwig2021-06-011-26/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Split __blkdev_put into one helper for the whole device, and one for partitions as well as another shared helper for flushing the block device inode mapping. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210525061301.2242282-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: move adjusting bd_part_count out of __blkdev_getChristoph Hellwig2021-06-011-9/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Keep in the callers and thus remove the for_part argument. This mirrors what is done on the blkdev_get side and slightly simplifies blkdev_get_part as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@rehat.com> Link: https://lore.kernel.org/r/20210525061301.2242282-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: move bd_mutex to struct gendiskChristoph Hellwig2021-06-011-22/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the per-block device bd_mutex with a per-gendisk open_mutex, thus simplifying locking wherever we deal with partitions. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Acked-by: Roger Pau Monné <roger.pau@citrix.com> Link: https://lore.kernel.org/r/20210525061301.2242282-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: move sync_blockdev from __blkdev_put to blkdev_putChristoph Hellwig2021-06-011-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Do the early unlocked syncing even earlier to move more code out of the recursive path. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20210525061301.2242282-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: split __blkdev_getChristoph Hellwig2021-06-011-61/+57
| |/ | | | | | | | | | | | | | | | | | | | | | | Split __blkdev_get into one helper for the whole device, and one for opening partitions. This removes the (bounded) recursion when opening a partition. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20210525061301.2242282-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* / mm: require ->set_page_dirty to be explicitly wired upChristoph Hellwig2021-06-291-0/+1
|/ | | | | | | | | | | | | | | | | | Remove the CONFIG_BLOCK default to __set_page_dirty_buffers and just wire that method up for the missing instances. [hch@lst.de: ecryptfs: add a ->set_page_dirty cludge] Link: https://lkml.kernel.org/r/20210624125250.536369-1-hch@lst.de Link: https://lkml.kernel.org/r/20210614061512.3966143-4-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Tyler Hicks <code@tyhicks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'block-5.13-2021-05-22' of git://git.kernel.dk/linux-blockLinus Torvalds2021-05-221-10/+8
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block fixes from Jens Axboe: - Fix BLKRRPART and deletion race (Gulam, Christoph) - NVMe pull request (Christoph): - nvme-tcp corruption and timeout fixes (Sagi Grimberg, Keith Busch) - nvme-fc teardown fix (James Smart) - nvmet/nvme-loop memory leak fixes (Wu Bo)" * tag 'block-5.13-2021-05-22' of git://git.kernel.dk/linux-block: block: fix a race between del_gendisk and BLKRRPART block: prevent block device lookups at the beginning of del_gendisk nvme-fc: clear q_live at beginning of association teardown nvme-tcp: rerun io_work if req_list is not empty nvme-tcp: fix possible use-after-completion nvme-loop: fix memory leak in nvme_loop_create_ctrl() nvmet: fix memory leak in nvmet_alloc_ctrl()
| * block: fix a race between del_gendisk and BLKRRPARTGulam Mohamed2021-05-201-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When BLKRRPART is called concurrently with del_gendisk, the partitions rescan can create a stale partition that will never be be cleaned up. Fix this by checking the the disk is up before rescanning partitions while under bd_mutex. Signed-off-by: Gulam Mohamed <gulam.mohamed@oracle.com> [hch: split from a larger patch] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210514131842.1600568-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * block: prevent block device lookups at the beginning of del_gendiskChristoph Hellwig2021-05-201-10/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | As an artifact of how gendisk lookup used to work in earlier kernels, GENHD_FL_UP is only cleared very late in del_gendisk, and a global lock is used to prevent opens from succeeding while del_gendisk is tearing down the gendisk. Switch to clearing the flag early and under bd_mutex so that callers can use bd_mutex to stabilize the flag, which removes the need for the global mutex. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210514131842.1600568-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | Merge tag 'block-5.13-2021-05-07' of git://git.kernel.dk/linux-blockLinus Torvalds2021-05-071-3/+17
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * block: reexpand iov_iter after read/writeyangerkun2021-05-061-3/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We get a bug: BUG: KASAN: slab-out-of-bounds in iov_iter_revert+0x11c/0x404 lib/iov_iter.c:1139 Read of size 8 at addr ffff0000d3fb11f8 by task CPU: 0 PID: 12582 Comm: syz-executor.2 Not tainted 5.10.0-00843-g352c8610ccd2 #2 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x0/0x2d0 arch/arm64/kernel/stacktrace.c:132 show_stack+0x28/0x34 arch/arm64/kernel/stacktrace.c:196 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x110/0x164 lib/dump_stack.c:118 print_address_description+0x78/0x5c8 mm/kasan/report.c:385 __kasan_report mm/kasan/report.c:545 [inline] kasan_report+0x148/0x1e4 mm/kasan/report.c:562 check_memory_region_inline mm/kasan/generic.c:183 [inline] __asan_load8+0xb4/0xbc mm/kasan/generic.c:252 iov_iter_revert+0x11c/0x404 lib/iov_iter.c:1139 io_read fs/io_uring.c:3421 [inline] io_issue_sqe+0x2344/0x2d64 fs/io_uring.c:5943 __io_queue_sqe+0x19c/0x520 fs/io_uring.c:6260 io_queue_sqe+0x2a4/0x590 fs/io_uring.c:6326 io_submit_sqe fs/io_uring.c:6395 [inline] io_submit_sqes+0x4c0/0xa04 fs/io_uring.c:6624 __do_sys_io_uring_enter fs/io_uring.c:9013 [inline] __se_sys_io_uring_enter fs/io_uring.c:8960 [inline] __arm64_sys_io_uring_enter+0x190/0x708 fs/io_uring.c:8960 __invoke_syscall arch/arm64/kernel/syscall.c:36 [inline] invoke_syscall arch/arm64/kernel/syscall.c:48 [inline] el0_svc_common arch/arm64/kernel/syscall.c:158 [inline] do_el0_svc+0x120/0x290 arch/arm64/kernel/syscall.c:227 el0_svc+0x1c/0x28 arch/arm64/kernel/entry-common.c:367 el0_sync_handler+0x98/0x170 arch/arm64/kernel/entry-common.c:383 el0_sync+0x140/0x180 arch/arm64/kernel/entry.S:670 Allocated by task 12570: stack_trace_save+0x80/0xb8 kernel/stacktrace.c:121 kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc+0xdc/0x120 mm/kasan/common.c:461 kasan_kmalloc+0xc/0x14 mm/kasan/common.c:475 __kmalloc+0x23c/0x334 mm/slub.c:3970 kmalloc include/linux/slab.h:557 [inline] __io_alloc_async_data+0x68/0x9c fs/io_uring.c:3210 io_setup_async_rw fs/io_uring.c:3229 [inline] io_read fs/io_uring.c:3436 [inline] io_issue_sqe+0x2954/0x2d64 fs/io_uring.c:5943 __io_queue_sqe+0x19c/0x520 fs/io_uring.c:6260 io_queue_sqe+0x2a4/0x590 fs/io_uring.c:6326 io_submit_sqe fs/io_uring.c:6395 [inline] io_submit_sqes+0x4c0/0xa04 fs/io_uring.c:6624 __do_sys_io_uring_enter fs/io_uring.c:9013 [inline] __se_sys_io_uring_enter fs/io_uring.c:8960 [inline] __arm64_sys_io_uring_enter+0x190/0x708 fs/io_uring.c:8960 __invoke_syscall arch/arm64/kernel/syscall.c:36 [inline] invoke_syscall arch/arm64/kernel/syscall.c:48 [inline] el0_svc_common arch/arm64/kernel/syscall.c:158 [inline] do_el0_svc+0x120/0x290 arch/arm64/kernel/syscall.c:227 el0_svc+0x1c/0x28 arch/arm64/kernel/entry-common.c:367 el0_sync_handler+0x98/0x170 arch/arm64/kernel/entry-common.c:383 el0_sync+0x140/0x180 arch/arm64/kernel/entry.S:670 Freed by task 12570: stack_trace_save+0x80/0xb8 kernel/stacktrace.c:121 kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track+0x38/0x6c mm/kasan/common.c:56 kasan_set_free_info+0x20/0x40 mm/kasan/generic.c:355 __kasan_slab_free+0x124/0x150 mm/kasan/common.c:422 kasan_slab_free+0x10/0x1c mm/kasan/common.c:431 slab_free_hook mm/slub.c:1544 [inline] slab_free_freelist_hook mm/slub.c:1577 [inline] slab_free mm/slub.c:3142 [inline] kfree+0x104/0x38c mm/slub.c:4124 io_dismantle_req fs/io_uring.c:1855 [inline] __io_free_req+0x70/0x254 fs/io_uring.c:1867 io_put_req_find_next fs/io_uring.c:2173 [inline] __io_queue_sqe+0x1fc/0x520 fs/io_uring.c:6279 __io_req_task_submit+0x154/0x21c fs/io_uring.c:2051 io_req_task_submit+0x2c/0x44 fs/io_uring.c:2063 task_work_run+0xdc/0x128 kernel/task_work.c:151 get_signal+0x6f8/0x980 kernel/signal.c:2562 do_signal+0x108/0x3a4 arch/arm64/kernel/signal.c:658 do_notify_resume+0xbc/0x25c arch/arm64/kernel/signal.c:722 work_pending+0xc/0x180 blkdev_read_iter can truncate iov_iter's count since the count + pos may exceed the size of the blkdev. This will confuse io_read that we have consume the iovec. And once we do the iov_iter_revert in io_read, we will trigger the slab-out-of-bounds. Fix it by reexpand the count with size has been truncated. blkdev_write_iter can trigger the problem too. Signed-off-by: yangerkun <yangerkun@huawei.com> Acked-by: Pavel Begunkov <asml.silencec@gmail.com> Link: https://lore.kernel.org/r/20210401071807.3328235-1-yangerkun@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | mm: introduce and use mapping_empty()Matthew Wilcox (Oracle)2021-05-051-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "Remove nrexceptional tracking", v2. We actually use nrexceptional for very little these days. It's a minor pain to keep in sync with nrpages, but the pain becomes much bigger with the THP patches because we don't know how many indices a shadow entry occupies. It's easier to just remove it than keep it accurate. Also, we save 8 bytes per inode which is nothing to sneeze at; on my laptop, it would improve shmem_inode_cache from 22 to 23 objects per 16kB, and inode_cache from 26 to 27 objects. Combined, that saves a megabyte of memory from a combined usage of 25MB for both caches. Unfortunately, ext4 doesn't cross a magic boundary, so it doesn't save any memory for ext4. This patch (of 4): Instead of checking the two counters (nrpages and nrexceptional), we can just check whether i_pages is empty. Link: https://lkml.kernel.org/r/20201026151849.24232-1-willy@infradead.org Link: https://lkml.kernel.org/r/20201026151849.24232-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Vishal Verma <vishal.l.verma@intel.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'for-5.13/drivers-2021-04-27' of git://git.kernel.dk/linux-blockLinus Torvalds2021-04-281-9/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * block: remove the -ERESTARTSYS handling in blkdev_get_by_devChristoph Hellwig2021-04-121-6/+0
| | | | | | | | | | | | | | Now that md has been cleaned up we can get rid of this hack. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * block: remove the revalidate_disk methodChristoph Hellwig2021-03-291-3/+0
| | | | | | | | | | | | | | | | 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>
* | Merge tag 'for-5.13/block-2021-04-27' of git://git.kernel.dk/linux-blockLinus Torvalds2021-04-281-4/+6
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * | block: initialize ret in bdev_disk_changedChristoph Hellwig2021-04-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Avoid a potentially initialized variabe in the invalidate case. Fixes: d3c4a43d9291 ("block: refactor blk_drop_partitions") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Reviewed-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20210408194140.1816537-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | block: refactor blk_drop_partitionsChristoph Hellwig2021-04-081-3/+5
| |/ | | | | | | | | | | | | | | | | | | Move the busy check and disk-wide sync into the only caller, so that the remainder can be shared with del_gendisk. Also pass the gendisk instead of the bdev as that is all that is needed. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210406062303.811835-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: don't ignore REQ_NOWAIT for direct IOPavel Begunkov2021-04-021-0/+4
| | | | | | | | | | | | | | | | | | | | If IOCB_NOWAIT is set on submission, then that needs to get propagated to REQ_NOWAIT on the block side. Otherwise we completely lose this information, and any issuer of IOCB_NOWAIT IO will potentially end up blocking on eg request allocation on the storage side. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: clear GD_NEED_PART_SCAN later in bdev_disk_changedChris Chiu2021-03-231-2/+2
|/ | | | | | | | | | | | | | | | | | | The GD_NEED_PART_SCAN is set by bdev_check_media_change to initiate a partition scan while removing a block device. It should be cleared after blk_drop_paritions because blk_drop_paritions could return -EBUSY and then the consequence __blkdev_get has no chance to do delete_partition if GD_NEED_PART_SCAN already cleared. It causes some problems on some card readers. Ex. Realtek card reader 0bda:0328 and 0bda:0158. The device node of the partition will not disappear after the memory card removed. Thus the user applications can not update the device mapping correctly. BugLink: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1920874 Signed-off-by: Chris Chiu <chris.chiu@canonical.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210323085219.24428-1-chris.chiu@canonical.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: rename BIO_MAX_PAGES to BIO_MAX_VECSChristoph Hellwig2021-03-111-3/+3
| | | | | | | | | | | | Ever since the addition of multipage bio_vecs BIO_MAX_PAGES has been horribly confusingly misnamed. Rename it to BIO_MAX_VECS to stop confusing users of the bio API. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20210311110137.1132391-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: Try to handle busy underlying device on discardJan Kara2021-03-051-1/+10
| | | | | | | | | | | | | | | | | | | | | | | Commit 384d87ef2c95 ("block: Do not discard buffers under a mounted filesystem") made paths issuing discard or zeroout requests to the underlying device try to grab block device in exclusive mode. If that failed we returned EBUSY to userspace. This however caused unexpected fallout in userspace where e.g. FUSE filesystems issue discard requests from userspace daemons although the device is open exclusively by the kernel. Also shrinking of logical volume by LVM issues discard requests to a device which may be claimed exclusively because there's another LV on the same PV. So to avoid these userspace regressions, fall back to invalidate_inode_pages2_range() instead of returning EBUSY to userspace and return EBUSY only of that call fails as well (meaning that there's indeed someone using the particular device range we are trying to discard). Link: https://bugzilla.kernel.org/show_bug.cgi?id=211167 Fixes: 384d87ef2c95 ("block: Do not discard buffers under a mounted filesystem") CC: stable@vger.kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* Merge tag 'block-5.12-2021-02-27' of git://git.kernel.dk/linux-blockLinus Torvalds2021-02-281-5/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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() ...
| * block: Add bio_max_segsMatthew Wilcox (Oracle)2021-02-261-5/+5
| | | | | | | | | | | | | | | | | | | | It's often inconvenient to use BIO_MAX_PAGES due to min() requiring the sign to be the same. Introduce bio_max_segs() and change BIO_MAX_PAGES to be unsigned to make it easier for the users. Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>