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2024-02-08blk-iocost: Fix an UBSAN shift-out-of-bounds warningTejun Heo1-0/+7
When iocg_kick_delay() is called from a CPU different than the one which set the delay, @now may be in the past of @iocg->delay_at leading to the following warning: UBSAN: shift-out-of-bounds in block/blk-iocost.c:1359:23 shift exponent 18446744073709 is too large for 64-bit type 'u64' (aka 'unsigned long long') ... Call Trace: <TASK> dump_stack_lvl+0x79/0xc0 __ubsan_handle_shift_out_of_bounds+0x2ab/0x300 iocg_kick_delay+0x222/0x230 ioc_rqos_merge+0x1d7/0x2c0 __rq_qos_merge+0x2c/0x80 bio_attempt_back_merge+0x83/0x190 blk_attempt_plug_merge+0x101/0x150 blk_mq_submit_bio+0x2b1/0x720 submit_bio_noacct_nocheck+0x320/0x3e0 __swap_writepage+0x2ab/0x9d0 The underflow itself doesn't really affect the behavior in any meaningful way; however, the past timestamp may exaggerate the delay amount calculated later in the code, which shouldn't be a material problem given the nature of the delay mechanism. If @now is in the past, this CPU is racing another CPU which recently set up the delay and there's nothing this CPU can contribute w.r.t. the delay. Let's bail early from iocg_kick_delay() in such cases. Reported-by: Breno Leitão <leitao@debian.org> Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: 5160a5a53c0c ("blk-iocost: implement delay adjustment hysteresis") Link: https://lore.kernel.org/r/ZVvc9L_CYk5LO1fT@slm.duckdns.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-06blk-wbt: Fix detection of dirty-throttled tasksJan Kara1-2/+2
The detection of dirty-throttled tasks in blk-wbt has been subtly broken since its beginning in 2016. Namely if we are doing cgroup writeback and the throttled task is not in the root cgroup, balance_dirty_pages() will set dirty_sleep for the non-root bdi_writeback structure. However blk-wbt checks dirty_sleep only in the root cgroup bdi_writeback structure. Thus detection of recently throttled tasks is not working in this case (we noticed this when we switched to cgroup v2 and suddently writeback was slow). Since blk-wbt has no easy way to get to proper bdi_writeback and furthermore its intention has always been to work on the whole device rather than on individual cgroups, just move the dirty_sleep timestamp from bdi_writeback to backing_dev_info. That fixes the checking for recently throttled task and saves memory for everybody as a bonus. CC: stable@vger.kernel.org Fixes: b57d74aff9ab ("writeback: track if we're sleeping on progress in balance_dirty_pages()") Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20240123175826.21452-1-jack@suse.cz [axboe: fixup indentation errors] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-01block: Fix where bio IO priority gets setHongyu Jin2-10/+10
Commit 82b74cac2849 ("blk-ioprio: Convert from rqos policy to direct call") pushed setting bio I/O priority down into blk_mq_submit_bio() -- which is too low within block core's submit_bio() because it skips setting I/O priority for block drivers that implement fops->submit_bio() (e.g. DM, MD, etc). Fix this by moving bio_set_ioprio() up from blk-mq.c to blk-core.c and call it from submit_bio(). This ensures all block drivers call bio_set_ioprio() during initial bio submission. Fixes: a78418e6a04c ("block: Always initialize bio IO priority on submit") Co-developed-by: Yibin Ding <yibin.ding@unisoc.com> Signed-off-by: Yibin Ding <yibin.ding@unisoc.com> Signed-off-by: Hongyu Jin <hongyu.jin@unisoc.com> Reviewed-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Mikulas Patocka <mpatocka@redhat.com> [snitzer: revised commit header] Signed-off-by: Mike Snitzer <snitzer@kernel.org> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20240130202638.62600-2-snitzer@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-23block: Fix WARNING in _copy_from_iterChristian A. Ehrhardt1-3/+10
Syzkaller reports a warning in _copy_from_iter because an iov_iter is supposedly used in the wrong direction. The reason is that syzcaller managed to generate a request with a transfer direction of SG_DXFER_TO_FROM_DEV. This instructs the kernel to copy user buffers into the kernel, read into the copied buffers and then copy the data back to user space. Thus the iovec is used in both directions. Detect this situation in the block layer and construct a new iterator with the correct direction for the copy-in. Reported-by: syzbot+a532b03fdfee2c137666@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/0000000000009b92c10604d7a5e9@google.com/t/ Reported-by: syzbot+63dec323ac56c28e644f@syzkaller.appspotmail.com Closes: https://lore.kernel.org/lkml/0000000000003faaa105f6e7c658@google.com/T/ Signed-off-by: Christian A. Ehrhardt <lk@c--e.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240121202634.275068-1-lk@c--e.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-22block: Move checking GENHD_FL_NO_PART to bdev_add_partition()Li Lingfeng2-2/+5
Commit 1a721de8489f ("block: don't add or resize partition on the disk with GENHD_FL_NO_PART") prevented all operations about partitions on disks with GENHD_FL_NO_PART in blkpg_do_ioctl() since they are meaningless. However, it changed error code in some scenarios. So move checking GENHD_FL_NO_PART to bdev_add_partition() to eliminate impact. Fixes: 1a721de8489f ("block: don't add or resize partition on the disk with GENHD_FL_NO_PART") Reported-by: Allison Karlitskaya <allison.karlitskaya@redhat.com> Closes: https://lore.kernel.org/all/CAOYeF9VsmqKMcQjo1k6YkGNujwN-nzfxY17N3F-CMikE1tYp+w@mail.gmail.com/ Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20240118130401.792757-1-lilingfeng@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-19Merge tag 'for-6.8/block-2024-01-18' of git://git.kernel.dk/linuxLinus Torvalds8-62/+44
Pull block fixes from Jens Axboe: - NVMe pull request via Keith: - tcp, fc, and rdma target fixes (Maurizio, Daniel, Hannes, Christoph) - discard fixes and improvements (Christoph) - timeout debug improvements (Keith, Max) - various cleanups (Daniel, Max, Giuxen) - trace event string fixes (Arnd) - shadow doorbell setup on reset fix (William) - a write zeroes quirk for SK Hynix (Jim) - MD pull request via Song: - Sparse warning since v6.0 (Bart) - /proc/mdstat regression since v6.7 (Yu Kuai) - Use symbolic error value (Christian) - IO Priority documentation update (Christian) - Fix for accessing queue limits without having entered the queue (Christoph, me) - Fix for loop dio support (Christoph) - Move null_blk off deprecated ida interface (Christophe) - Ensure nbd initializes full msghdr (Eric) - Fix for a regression with the folio conversion, which is now easier to hit because of an unrelated change (Matthew) - Remove redundant check in virtio-blk (Li) - Fix for a potential hang in sbitmap (Ming) - Fix for partial zone appending (Damien) - Misc changes and fixes (Bart, me, Kemeng, Dmitry) * tag 'for-6.8/block-2024-01-18' of git://git.kernel.dk/linux: (45 commits) Documentation: block: ioprio: Update schedulers loop: fix the the direct I/O support check when used on top of block devices blk-mq: Remove the hctx 'run' debugfs attribute nbd: always initialize struct msghdr completely block: Fix iterating over an empty bio with bio_for_each_folio_all block: bio-integrity: fix kcalloc() arguments order virtio_blk: remove duplicate check if queue is broken in virtblk_done sbitmap: remove stale comment in sbq_calc_wake_batch block: Correct a documentation comment in blk-cgroup.c null_blk: Remove usage of the deprecated ida_simple_xx() API block: ensure we hold a queue reference when using queue limits blk-mq: rename blk_mq_can_use_cached_rq block: print symbolic error name instead of error code blk-mq: fix IO hang from sbitmap wakeup race nvmet-rdma: avoid circular locking dependency on install_queue() nvmet-tcp: avoid circular locking dependency on install_queue() nvme-pci: set doorbell config before unquiescing block: fix partial zone append completion handling in req_bio_endio() block/iocost: silence warning on 'last_period' potentially being unused md/raid1: Use blk_opf_t for read and write operations ...
2024-01-18blk-mq: Remove the hctx 'run' debugfs attributeBart Van Assche2-20/+0
Nobody uses the debugfs hctx 'run' attribute. Hence remove this attribute and also the code that updates the corresponding member variable. Suggested-by: Jens Axboe <axboe@kernel.dk> Cc: Gabriel Ryan <gabe@cs.columbia.edu> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20240117203609.4122520-1-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-16block: bio-integrity: fix kcalloc() arguments orderDmitry Antipov1-1/+1
When compiling with gcc version 14.0.1 20240116 (experimental) and W=1, I've noticed the following warning: block/bio-integrity.c: In function 'bio_integrity_map_user': block/bio-integrity.c:339:38: warning: 'kcalloc' sizes specified with 'sizeof' in the earlier argument and not in the later argument [-Wcalloc-transposed-args] 339 | bvec = kcalloc(sizeof(*bvec), nr_vecs, GFP_KERNEL); | ^ block/bio-integrity.c:339:38: note: earlier argument should specify number of elements, later size of each element Since 'n' and 'size' arguments of 'kcalloc()' are multiplied to calculate the final size, their actual order doesn't affect the result and so this is not a bug. But it's still worth to fix it. Fixes: 492c5d455969 ("block: bio-integrity: directly map user buffers") Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> Reviewed-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20240116143437.89060-1-dmantipov@yandex.ru Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-15block: Correct a documentation comment in blk-cgroup.cNicky Chorley1-1/+1
Commit 99e603874366 ("blk-cgroup: pass a gendisk to the blkg allocation helpers") changed blkg_alloc() to take a struct gendisk instead of a struct request_queue, but the documentation comment still referred to q. So, update that comment to refer to disk instead and fix a typo. Signed-off-by: Nicky Chorley <ndchorley@gmail.com> Link: https://lore.kernel.org/r/20240114191056.6992-1-ndchorley@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-13block: ensure we hold a queue reference when using queue limitsJens Axboe1-6/+10
q_usage_counter is the only thing preventing us from the limits changing under us in __bio_split_to_limits, but blk_mq_submit_bio doesn't hold it while calling into it. Move the splitting inside the region where we know we've got a queue reference. Ideally this could still remain a shared section of code, but let's keep the fix simple and defer any refactoring here to later. Reported-by: Christoph Hellwig <hch@lst.de> Fixes: 900e08075202 ("block: move queue enter logic into blk_mq_submit_bio()") Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-12blk-mq: rename blk_mq_can_use_cached_rqChristoph Hellwig1-3/+6
blk_mq_can_use_cached_rq doesn't just check if we can use the request, but also performs the work to actually use it. Remove the _can in the naming, and improve the comment describing the function. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240111135705.2155518-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-12block: print symbolic error name instead of error codeChristian Heusel1-2/+2
Utilize the %pe print specifier to get the symbolic error name as a string (i.e "-ENOMEM") in the log message instead of the error code to increase its readablility. This change was suggested in https://lore.kernel.org/all/92972476-0b1f-4d0a-9951-af3fc8bc6e65@suswa.mountain/ Signed-off-by: Christian Heusel <christian@heusel.eu> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20240111231521.1596838-1-christian@heusel.eu Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-12blk-mq: fix IO hang from sbitmap wakeup raceMing Lei1-0/+16
In blk_mq_mark_tag_wait(), __add_wait_queue() may be re-ordered with the following blk_mq_get_driver_tag() in case of getting driver tag failure. Then in __sbitmap_queue_wake_up(), waitqueue_active() may not observe the added waiter in blk_mq_mark_tag_wait() and wake up nothing, meantime blk_mq_mark_tag_wait() can't get driver tag successfully. This issue can be reproduced by running the following test in loop, and fio hang can be observed in < 30min when running it on my test VM in laptop. modprobe -r scsi_debug modprobe scsi_debug delay=0 dev_size_mb=4096 max_queue=1 host_max_queue=1 submit_queues=4 dev=`ls -d /sys/bus/pseudo/drivers/scsi_debug/adapter*/host*/target*/*/block/* | head -1 | xargs basename` fio --filename=/dev/"$dev" --direct=1 --rw=randrw --bs=4k --iodepth=1 \ --runtime=100 --numjobs=40 --time_based --name=test \ --ioengine=libaio Fix the issue by adding one explicit barrier in blk_mq_mark_tag_wait(), which is just fine in case of running out of tag. Cc: Jan Kara <jack@suse.cz> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Reported-by: Changhui Zhong <czhong@redhat.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20240112122626.4181044-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-12Merge tag 'for-6.8/block-2024-01-08' of git://git.kernel.dk/linuxLinus Torvalds17-185/+320
Pull block updates from Jens Axboe: "Pretty quiet round this time around. This contains: - NVMe updates via Keith: - nvme fabrics spec updates (Guixin, Max) - nvme target udpates (Guixin, Evan) - nvme attribute refactoring (Daniel) - nvme-fc numa fix (Keith) - MD updates via Song: - Fix/Cleanup RCU usage from conf->disks[i].rdev (Yu Kuai) - Fix raid5 hang issue (Junxiao Bi) - Add Yu Kuai as Reviewer of the md subsystem - Remove deprecated flavors (Song Liu) - raid1 read error check support (Li Nan) - Better handle events off-by-1 case (Alex Lyakas) - Efficiency improvements for passthrough (Kundan) - Support for mapping integrity data directly (Keith) - Zoned write fix (Damien) - rnbd fixes (Kees, Santosh, Supriti) - Default to a sane discard size granularity (Christoph) - Make the default max transfer size naming less confusing (Christoph) - Remove support for deprecated host aware zoned model (Christoph) - Misc fixes (me, Li, Matthew, Min, Ming, Randy, liyouhong, Daniel, Bart, Christoph)" * tag 'for-6.8/block-2024-01-08' of git://git.kernel.dk/linux: (78 commits) block: Treat sequential write preferred zone type as invalid block: remove disk_clear_zoned sd: remove the !ZBC && blk_queue_is_zoned case in sd_read_block_characteristics drivers/block/xen-blkback/common.h: Fix spelling typo in comment blk-cgroup: fix rcu lockdep warning in blkg_lookup() blk-cgroup: don't use removal safe list iterators block: floor the discard granularity to the physical block size mtd_blkdevs: use the default discard granularity bcache: use the default discard granularity zram: use the default discard granularity null_blk: use the default discard granularity nbd: use the default discard granularity ubd: use the default discard granularity block: default the discard granularity to sector size bcache: discard_granularity should not be smaller than a sector block: remove two comments in bio_split_discard block: rename and document BLK_DEF_MAX_SECTORS loop: don't abuse BLK_DEF_MAX_SECTORS aoe: don't abuse BLK_DEF_MAX_SECTORS null_blk: don't cap max_hw_sectors to BLK_DEF_MAX_SECTORS ...
2024-01-10block: fix partial zone append completion handling in req_bio_endio()Damien Le Moal1-2/+7
Partial completions of zone append request is not allowed but if a zone append completion indicates a number of completed bytes different from the original BIO size, only the BIO status is set to error. This leads to bio_advance() not setting the BIO size to 0 and thus to not call bio_endio() at the end of req_bio_endio(). Make sure a partially completed zone append is failed and completed immediately by forcing the completed number of bytes (nbytes) to be equal to the BIO size, thus ensuring that bio_endio() is called. Fixes: 297db731847e ("block: fix req_bio_endio append error handling") Cc: stable@kernel.vger.org Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20240110092942.442334-1-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-10block/iocost: silence warning on 'last_period' potentially being unusedJens Axboe1-1/+1
If CONFIG_TRACEPOINTS isn't enabled, we assign this variable but then never use it. This can cause the compiler to complain about that: block/blk-iocost.c:1264:6: warning: variable 'last_period' set but not used [-Wunused-but-set-variable] 1264 | u64 last_period, cur_period; | ^ Rather than add ifdefs to guard this, just mark it __maybe_unused. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202401102335.GiWdeIo9-lkp@intel.com/ Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-09Merge tag 'mm-stable-2024-01-08-15-31' of ↵Linus Torvalds1-4/+19
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Many singleton patches against the MM code. The patch series which are included in this merge do the following: - Peng Zhang has done some mapletree maintainance work in the series 'maple_tree: add mt_free_one() and mt_attr() helpers' 'Some cleanups of maple tree' - In the series 'mm: use memmap_on_memory semantics for dax/kmem' Vishal Verma has altered the interworking between memory-hotplug and dax/kmem so that newly added 'device memory' can more easily have its memmap placed within that newly added memory. - Matthew Wilcox continues folio-related work (including a few fixes) in the patch series 'Add folio_zero_tail() and folio_fill_tail()' 'Make folio_start_writeback return void' 'Fix fault handler's handling of poisoned tail pages' 'Convert aops->error_remove_page to ->error_remove_folio' 'Finish two folio conversions' 'More swap folio conversions' - Kefeng Wang has also contributed folio-related work in the series 'mm: cleanup and use more folio in page fault' - Jim Cromie has improved the kmemleak reporting output in the series 'tweak kmemleak report format'. - In the series 'stackdepot: allow evicting stack traces' Andrey Konovalov to permits clients (in this case KASAN) to cause eviction of no longer needed stack traces. - Charan Teja Kalla has fixed some accounting issues in the page allocator's atomic reserve calculations in the series 'mm: page_alloc: fixes for high atomic reserve caluculations'. - Dmitry Rokosov has added to the samples/ dorectory some sample code for a userspace memcg event listener application. See the series 'samples: introduce cgroup events listeners'. - Some mapletree maintanance work from Liam Howlett in the series 'maple_tree: iterator state changes'. - Nhat Pham has improved zswap's approach to writeback in the series 'workload-specific and memory pressure-driven zswap writeback'. - DAMON/DAMOS feature and maintenance work from SeongJae Park in the series 'mm/damon: let users feed and tame/auto-tune DAMOS' 'selftests/damon: add Python-written DAMON functionality tests' 'mm/damon: misc updates for 6.8' - Yosry Ahmed has improved memcg's stats flushing in the series 'mm: memcg: subtree stats flushing and thresholds'. - In the series 'Multi-size THP for anonymous memory' Ryan Roberts has added a runtime opt-in feature to transparent hugepages which improves performance by allocating larger chunks of memory during anonymous page faults. - Matthew Wilcox has also contributed some cleanup and maintenance work against eh buffer_head code int he series 'More buffer_head cleanups'. - Suren Baghdasaryan has done work on Andrea Arcangeli's series 'userfaultfd move option'. UFFDIO_MOVE permits userspace heap compaction algorithms to move userspace's pages around rather than UFFDIO_COPY'a alloc/copy/free. - Stefan Roesch has developed a 'KSM Advisor', in the series 'mm/ksm: Add ksm advisor'. This is a governor which tunes KSM's scanning aggressiveness in response to userspace's current needs. - Chengming Zhou has optimized zswap's temporary working memory use in the series 'mm/zswap: dstmem reuse optimizations and cleanups'. - Matthew Wilcox has performed some maintenance work on the writeback code, both code and within filesystems. The series is 'Clean up the writeback paths'. - Andrey Konovalov has optimized KASAN's handling of alloc and free stack traces for secondary-level allocators, in the series 'kasan: save mempool stack traces'. - Andrey also performed some KASAN maintenance work in the series 'kasan: assorted clean-ups'. - David Hildenbrand has gone to town on the rmap code. Cleanups, more pte batching, folio conversions and more. See the series 'mm/rmap: interface overhaul'. - Kinsey Ho has contributed some maintenance work on the MGLRU code in the series 'mm/mglru: Kconfig cleanup'. - Matthew Wilcox has contributed lruvec page accounting code cleanups in the series 'Remove some lruvec page accounting functions'" * tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (361 commits) mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER mm, treewide: introduce NR_PAGE_ORDERS selftests/mm: add separate UFFDIO_MOVE test for PMD splitting selftests/mm: skip test if application doesn't has root privileges selftests/mm: conform test to TAP format output selftests: mm: hugepage-mmap: conform to TAP format output selftests/mm: gup_test: conform test to TAP format output mm/selftests: hugepage-mremap: conform test to TAP format output mm/vmstat: move pgdemote_* out of CONFIG_NUMA_BALANCING mm: zsmalloc: return -ENOSPC rather than -EINVAL in zs_malloc while size is too large mm/memcontrol: remove __mod_lruvec_page_state() mm/khugepaged: use a folio more in collapse_file() slub: use a folio in __kmalloc_large_node slub: use folio APIs in free_large_kmalloc() slub: use alloc_pages_node() in alloc_slab_page() mm: remove inc/dec lruvec page state functions mm: ratelimit stat flush from workingset shrinker kasan: stop leaking stack trace handles mm/mglru: remove CONFIG_TRANSPARENT_HUGEPAGE mm/mglru: add dummy pmd_dirty() ...
2024-01-08block: move __get_task_ioprio() into header fileJens Axboe1-26/+0
We call this once per IO, which can be millions of times per second. Since nobody really uses io priorities, or at least it isn't very common, this is all wasted time and can amount to as much as 3% of the total kernel time. Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-08Merge tag 'vfs-6.8.super' of ↵Linus Torvalds2-107/+171
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs super updates from Christian Brauner: "This contains the super work for this cycle including the long-awaited series by Jan to make it possible to prevent writing to mounted block devices: - Writing to mounted devices is dangerous and can lead to filesystem corruption as well as crashes. Furthermore syzbot comes with more and more involved examples how to corrupt block device under a mounted filesystem leading to kernel crashes and reports we can do nothing about. Add tracking of writers to each block device and a kernel cmdline argument which controls whether other writeable opens to block devices open with BLK_OPEN_RESTRICT_WRITES flag are allowed. Note that this effectively only prevents modification of the particular block device's page cache by other writers. The actual device content can still be modified by other means - e.g. by issuing direct scsi commands, by doing writes through devices lower in the storage stack (e.g. in case loop devices, DM, or MD are involved) etc. But blocking direct modifications of the block device page cache is enough to give filesystems a chance to perform data validation when loading data from the underlying storage and thus prevent kernel crashes. Syzbot can use this cmdline argument option to avoid uninteresting crashes. Also users whose userspace setup does not need writing to mounted block devices can set this option for hardening. We expect that this will be interesting to quite a few workloads. Btrfs is currently opted out of this because they still haven't merged patches we require for this to work from three kernel releases ago. - Reimplement block device freezing and thawing as holder operations on the block device. This allows us to extend block device freezing to all devices associated with a superblock and not just the main device. It also allows us to remove get_active_super() and thus another function that scans the global list of superblocks. Freezing via additional block devices only works if the filesystem chooses to use @fs_holder_ops for these additional devices as well. That currently only includes ext4 and xfs. Earlier releases switched get_tree_bdev() and mount_bdev() to use @fs_holder_ops. The remaining nilfs2 open-coded version of mount_bdev() has been converted to rely on @fs_holder_ops as well. So block device freezing for the main block device will continue to work as before. There should be no regressions in functionality. The only special case is btrfs where block device freezing for the main block device never worked because sb->s_bdev isn't set. Block device freezing for btrfs can be fixed once they can switch to @fs_holder_ops but that can happen whenever they're ready" * tag 'vfs-6.8.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (27 commits) block: Fix a memory leak in bdev_open_by_dev() super: don't bother with WARN_ON_ONCE() super: massage wait event mechanism ext4: Block writes to journal device xfs: Block writes to log device fs: Block writes to mounted block devices btrfs: Do not restrict writes to btrfs devices block: Add config option to not allow writing to mounted devices block: Remove blkdev_get_by_*() functions bcachefs: Convert to bdev_open_by_path() fs: handle freezing from multiple devices fs: remove dead check nilfs2: simplify device handling fs: streamline thaw_super_locked ext4: simplify device handling xfs: simplify device handling fs: simplify setup_bdev_super() calls blkdev: comment fs_holder_ops porting: document block device freeze and thaw changes fs: remove unused helper ...
2024-01-08block: Treat sequential write preferred zone type as invalidDamien Le Moal1-1/+1
With the removal of the support for host-aware zoned devices, blk_revalidate_zone_cb() should never see the zone type BLK_ZONE_TYPE_SEQWRITE_PREF (sequential write preffered zones). Treat this zone type as being invalid. Fixes: 7437bb73f087 ("block: remove support for the host aware zone model") Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240107072212.1071080-1-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-08block: remove disk_clear_zonedChristoph Hellwig1-21/+0
disk_clear_zoned is unused now that the last warts of the host-aware model support in sd are gone. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20231228075141.362560-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-05blk-cgroup: fix rcu lockdep warning in blkg_lookup()Ming Lei1-1/+2
blkg_lookup() is called with either queue_lock or rcu read lock, so use rcu_dereference_check(lockdep_is_held(&q->queue_lock)) for retrieving 'blkg', which way models the check exactly for covering queue lock or rcu read lock. Fix lockdep warning of "block/blk-cgroup.h:254 suspicious rcu_dereference_check() usage!" from blkg_lookup(). Tested-by: Changhui Zhong <czhong@redhat.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Fixes: 83462a6c971c ("blkcg: Drop unnecessary RCU read [un]locks from blkg_conf_prep/finish()") Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20231219012833.2129540-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-05blk-cgroup: don't use removal safe list iteratorsDaniel Vacek1-2/+2
Commit f1c006f1c685 moved deletion of the list blkg->q_node from blkg_destroy() to blkg_free_workfn(). Switch to using the list iterators, as we don't need removal protection anymore. Signed-off-by: Daniel Vacek <neelx@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20240104180031.148148-1-neelx@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-05block: floor the discard granularity to the physical block sizeChristoph Hellwig1-0/+3
Discarding less than a physical block doesn't make sense. This fixes the existing behavior for zram before the recent changes to default the discard granularity to the logical block size, and is also a generally useful sanity check. Fixes: 3753039def5d ("zram: use the default discard granularity") Reported-by: Sergey Senozhatsky <senozhatsky@chromium.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240103081622.508754-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-29fs: convert block_write_full_page to block_write_full_folioMatthew Wilcox (Oracle)1-3/+18
Convert the function to be compatible with writepage_t so that it can be passed to write_cache_pages() by blkdev. This removes a call to compound_head(). We can also remove the function export as both callers are built-in. Link: https://lkml.kernel.org/r/20231215200245.748418-14-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29Merge tag 'block-6.7-2023-12-29' of git://git.kernel.dk/linuxLinus Torvalds1-2/+4
Pull block fixes from Jens Axboe: "Fix for a badly numbered flag, and a regression fix for the badblocks updates from this merge window" * tag 'block-6.7-2023-12-29' of git://git.kernel.dk/linux: block: renumber QUEUE_FLAG_HW_WC badblocks: avoid checking invalid range in badblocks_check()
2023-12-29block: default the discard granularity to sector sizeChristoph Hellwig1-1/+4
Current the discard granularity defaults to 0 and must be initialized by any driver that wants to support discard. Default to the sector size instead, which is the smallest possible value, and a very useful default. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20231228075545.362768-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-29block: remove two comments in bio_split_discardChristoph Hellwig1-5/+1
A zero discard_granularity is not treated the same as a single-block one, and not having any segments after taking alignment is perfectly fine and does not need a warning. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20231228075545.362768-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-28block: Fix a memory leak in bdev_open_by_dev()Christophe JAILLET1-2/+4
If we early exit here, 'handle' needs to be freed, or some memory leaks. Fixes: ed5cc702d311 ("block: Add config option to not allow writing to mounted devices") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Link: https://lore.kernel.org/r/8eaec334781e695810aaa383b55de00ca4ab1352.1703439383.git.christophe.jaillet@wanadoo.fr Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-12-27block: rename and document BLK_DEF_MAX_SECTORSChristoph Hellwig2-2/+2
Give BLK_DEF_MAX_SECTORS a _CAP postfix and document what it is used for. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20231227092305.279567-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-26blk-wbt: remove the separate write cache trackingChristoph Hellwig3-18/+2
Use the queue wide write back cache tracking insted of duplicating the value in strut rq_wb. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20231226090747.204969-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-26block: reject invalid operation in submit_bio_noacctChristoph Hellwig1-5/+21
submit_bio_noacct allows completely invalid operations, or operations that are not supported in the bio path. Extent the existing switch statement to rejcect all invalid types. Move the code point for REQ_OP_ZONE_APPEND so that it's not right in the middle of the zone management operations and the switch statement can follow the numerical order of the operations. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20231221070538.1112446-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-24badblocks: avoid checking invalid range in badblocks_check()Coly Li1-2/+4
If prev_badblocks() returns '-1', it means no valid badblocks record before the checking range. It doesn't make sense to check whether the input checking range is overlapped with the non-existed invalid front range. This patch checkes whether 'prev >= 0' is true before calling overlap_front(), to void such invalid operations. Fixes: 3ea3354cb9f0 ("badblocks: improve badblocks_check() for multiple ranges handling") Reported-and-tested-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Coly Li <colyli@suse.de> Link: https://lore.kernel.org/nvdimm/3035e75a-9be0-4bc3-8d4a-6e52c207f277@leemhuis.info/ Cc: Dan Williams <dan.j.williams@intel.com> Cc: Geliang Tang <geliang.tang@suse.com> Cc: Hannes Reinecke <hare@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: NeilBrown <neilb@suse.de> Cc: Vishal L Verma <vishal.l.verma@intel.com> Cc: Xiao Ni <xni@redhat.com> Link: https://lore.kernel.org/r/20231224002820.20234-1-colyli@suse.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-21block: export disk_clear_zoned()Jens Axboe1-0/+1
A previous commit split disk_set_zoned(..., bool) into not taking an argument for whether to set or clear, and instead added disk_clear_zoned() as the counterpart. However, that commit neglected to export the new symbol, causing failures for modular drivers that used it. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Fixes: d73e93b4dfab ("block: simplify disk_set_zoned") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-20block: simplify disk_set_zonedChristoph Hellwig3-24/+13
Only use disk_set_zoned to actually enable zoned device support. For clearing it, call disk_clear_zoned, which is renamed from disk_clear_zone_settings and now directly clears the zoned flag as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20231217165359.604246-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-20block: remove support for the host aware zone modelChristoph Hellwig3-75/+13
When zones were first added the SCSI and ATA specs, two different models were supported (in addition to the drive managed one that is invisible to the host): - host managed where non-conventional zones there is strict requirement to write at the write pointer, or else an error is returned - host aware where a write point is maintained if writes always happen at it, otherwise it is left in an under-defined state and the sequential write preferred zones behave like conventional zones (probably very badly performing ones, though) Not surprisingly this lukewarm model didn't prove to be very useful and was finally removed from the ZBC and SBC specs (NVMe never implemented it). Due to to the easily disappearing write pointer host software could never rely on the write pointer to actually be useful for say recovery. Fortunately only a few HDD prototypes shipped using this model which never made it to mass production. Drop the support before it is too late. Note that any such host aware prototype HDD can still be used with Linux as we'll now treat it as a conventional HDD. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20231217165359.604246-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-19block: add check of 'minors' and 'first_minor' in device_add_disk()Li Nan1-1/+3
'first_minor' represents the starting minor number of disks, and 'minors' represents the number of partitions in the device. Neither of them can be greater than MINORMASK + 1. Commit e338924bd05d ("block: check minor range in device_add_disk()") only added the check of 'first_minor + minors'. However, their sum might be less than MINORMASK but their values are wrong. Complete the checks now. Fixes: e338924bd05d ("block: check minor range in device_add_disk()") Signed-off-by: Li Nan <linan122@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20231219075942.840255-1-linan666@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-18block: skip cgroups for passthrough ioKundan Kumar1-0/+3
Even if BLK_CGROUP is enabled, it does not work for passthrough io. So skip setting up blkg for passthrough bio. Reduced processing gives ~5% hike in peak-performance workload. Signed-off-by: Kundan Kumar <kundan.kumar@samsung.com> Signed-off-by: Kanchan Joshi <joshi.k@samsung.com> Reviewed-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20231218152722.1768-1-joshi.k@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-15block: support adding less than len in bio_add_hw_pageChristoph Hellwig1-1/+4
bio_add_hw_page currently always fails or succeeds. This is fine for the existing callers that always add PAGE_SIZE worth given that the max_segment_size and max_sectors must always allow at least a page worth of data. But when we want to add it for bigger amounts of data this means it can also fail when adding the data to a bio, and creating a fallback for that becomes really annoying in the callers. Make use of the existing API design that allows to return a smaller length than the one passed in and add up to max_segment_size worth of data from a larger input. All the existing callers are fine with this - not because they handle this return correctly, but because they never pass more than a page in. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20231204173419.782378-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-15block: prevent an integer overflow in bvec_try_merge_hw_pageChristoph Hellwig1-1/+1
Reordered a check to avoid a possible overflow when adding len to bv_len. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20231204173419.782378-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-14block: Use pr_info() instead of printk(KERN_INFO ...)Bart Van Assche1-8/+4
Switch to the modern style of printing kernel messages. Use %u instead of %d to print unsigned integers. Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Cc: Keith Busch <kbusch@kernel.org> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20231213194702.90381-1-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-13block: add check that partition length needs to be aligned with block sizeMin Li1-4/+7
Before calling add partition or resize partition, there is no check on whether the length is aligned with the logical block size. If the logical block size of the disk is larger than 512 bytes, then the partition size maybe not the multiple of the logical block size, and when the last sector is read, bio_truncate() will adjust the bio size, resulting in an IO error if the size of the read command is smaller than the logical block size.If integrity data is supported, this will also result in a null pointer dereference when calling bio_integrity_free. Cc: <stable@vger.kernel.org> Signed-off-by: Min Li <min15.li@samsung.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230629142517.121241-1-min15.li@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-13block: Set memalloc_noio to false on device_add_disk() error pathLi Nan1-0/+1
On the error path of device_add_disk(), device's memalloc_noio flag was set but not cleared. As the comment of pm_runtime_set_memalloc_noio(), "The function should be called between device_add() and device_del()". Clear this flag before device_del() now. Fixes: 25e823c8c37d ("block/genhd.c: apply pm_runtime_set_memalloc_noio on block devices") Signed-off-by: Li Nan <linan122@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20231211075356.1839282-1-linan666@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-11fs: convert error_remove_page to error_remove_folioMatthew Wilcox (Oracle)1-1/+1
There were already assertions that we were not passing a tail page to error_remove_page(), so make the compiler enforce that by converting everything to pass and use a folio. Link: https://lkml.kernel.org/r/20231117161447.2461643-7-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-08block: Remove special-casing of compound pagesMatthew Wilcox (Oracle)1-22/+24
The special casing was originally added in pre-git history; reproducing the commit log here: > commit a318a92567d77 > Author: Andrew Morton <akpm@osdl.org> > Date: Sun Sep 21 01:42:22 2003 -0700 > > [PATCH] Speed up direct-io hugetlbpage handling > > This patch short-circuits all the direct-io page dirtying logic for > higher-order pages. Without this, we pointlessly bounce BIOs up to > keventd all the time. In the last twenty years, compound pages have become used for more than just hugetlb. Rewrite these functions to operate on folios instead of pages and remove the special case for hugetlbfs; I don't think it's needed any more (and if it is, we can put it back in as a call to folio_test_hugetlb()). This was found by inspection; as far as I can tell, this bug can lead to pages used as the destination of a direct I/O read not being marked as dirty. If those pages are then reclaimed by the MM without being dirtied for some other reason, they won't be written out. Then when they're faulted back in, they will not contain the data they should. It'll take a pretty unusual setup to produce this problem with several races all going the wrong way. This problem predates the folio work; it could for example have been triggered by mmaping a THP in tmpfs and using that as the target of an O_DIRECT read. Fixes: 800d8c63b2e98 ("shmem: add huge pages support") Cc: <stable@vger.kernel.org> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-02block: skip QUEUE_FLAG_STATS and rq-qos for passthrough ioKundan Kumar2-2/+3
Write-back throttling (WBT) enables QUEUE_FLAG_STATS on the request queue. But WBT does not make sense for passthrough io, so skip QUEUE_FLAG_STATS processing. Also skip rq_qos_issue/done for passthrough io. Overall, the change gives ~11% hike in peak performance. Signed-off-by: Kundan Kumar <kundan.kumar@samsung.com> Signed-off-by: Kanchan Joshi <joshi.k@samsung.com> Link: https://lore.kernel.org/r/20231123190331.7934-1-kundan.kumar@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-02block: bio-integrity: directly map user buffersKeith Busch1-2/+216
Passthrough commands that utilize metadata currently need to bounce the user space buffer through the kernel. Add support for mapping user space directly so that we can avoid this costly overhead. This is similar to how the normal bio data payload utilizes user addresses with bio_map_user_iov(). If the user address can't directly be used for reason, like too many segments or address unalignement, fallback to a copy of the user vec while keeping the user address pinned for the IO duration so that it can safely be copied on completion in any process context. Signed-off-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20231130215309.2923568-2-kbusch@meta.com [axboe: fold in fix from Kanchan Joshi] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-12-02Merge tag 'block-6.7-2023-12-01' of git://git.kernel.dk/linuxLinus Torvalds3-4/+26
Pull block fixes from Jens Axboe: - NVMe pull request via Keith: - Invalid namespace identification error handling (Marizio Ewan, Keith) - Fabrics keep-alive tuning (Mark) - Fix for a bad error check regression in bcache (Markus) - Fix for a performance regression with O_DIRECT (Ming) - Fix for a flush related deadlock (Ming) - Make the read-only warn on per-partition (Yu) * tag 'block-6.7-2023-12-01' of git://git.kernel.dk/linux: nvme-core: check for too small lba shift blk-mq: don't count completed flush data request as inflight in case of quiesce block: Document the role of the two attribute groups block: warn once for each partition in bio_check_ro() block: move .bd_inode into 1st cacheline of block_device nvme: check for valid nvme_identify_ns() before using it nvme-core: fix a memory leak in nvme_ns_info_from_identify() nvme: fine-tune sending of first keep-alive bcache: revert replacing IS_ERR_OR_NULL with IS_ERR
2023-12-01blk-mq: don't count completed flush data request as inflight in case of quiesceMing Lei1-1/+13
Request queue quiesce may interrupt flush sequence, and the original request may have been marked as COMPLETE, but can't get finished because of queue quiesce. This way is fine from driver viewpoint, because flush sequence is block layer concept, and it isn't related with driver. However, driver(such as dm-rq) can call blk_mq_queue_inflight() to count & drain inflight requests, then the wait & drain never gets done because the completed & not-finished flush request is counted as inflight. Fix this issue by not counting completed flush data request as inflight in case of quiesce. Cc: Mike Snitzer <snitzer@kernel.org> Cc: David Jeffery <djeffery@redhat.com> Cc: John Pittman <jpittman@redhat.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20231201085605.577730-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-11-29block: Document the role of the two attribute groupsBart Van Assche1-0/+2
It is nontrivial to derive the role of the two attribute groups in source file block/blk-sysfs.c. Hence add a comment that explains their roles. See also commit 6d85ebf95c44 ("blk-sysfs: add a new attr_group for blk_mq"). Cc: Christoph Hellwig <hch@lst.de> Cc: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20231128194019.72762-1-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>