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path: root/drivers/block/loop.c
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2022-02-12block: loop:use kstatfs.f_bsize of backing file to set discard granularityMing Lei1-1/+7
If backing file's filesystem has implemented ->fallocate(), we think the loop device can support discard, then pass sb->s_blocksize as discard_granularity. However, some underlying FS, such as overlayfs, doesn't set sb->s_blocksize, and causes discard_granularity to be set as zero, then the warning in __blkdev_issue_discard() is triggered. Christoph suggested to pass kstatfs.f_bsize as discard granularity, and this way is fine because kstatfs.f_bsize means 'Optimal transfer block size', which still matches with definition of discard granularity. So fix the issue by setting discard_granularity as kstatfs.f_bsize if it is available, otherwise claims discard isn't supported. Cc: Christoph Hellwig <hch@lst.de> Cc: Vivek Goyal <vgoyal@redhat.com> Reported-by: Pei Zhang <pezhang@redhat.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220126035830.296465-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-11loop: revert "make autoclear operation asynchronous"Tetsuo Handa1-36/+29
The kernel test robot is reporting that xfstest which does umount ext2 on xfs umount xfs sequence started failing, for commit 322c4293ecc58110 ("loop: make autoclear operation asynchronous") removed a guarantee that fput() of backing file is processed before lo_release() from close() returns to user mode. And syzbot is reporting that deferring destroy_workqueue() from __loop_clr_fd() to a WQ context did not help [1]. Revert that commit. Link: https://syzkaller.appspot.com/bug?extid=831661966588c802aae9 [1] Reported-by: kernel test robot <oliver.sang@intel.com> Acked-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Reported-by: syzbot <syzbot+831661966588c802aae9@syzkaller.appspotmail.com> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Link: https://lore.kernel.org/r/20220211071554.3424-1-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-01-13loop: remove redundant initialization of pointer nodeColin Ian King1-1/+1
The pointer node is being initialized with a value that is never read, it is being re-assigned the same value a little futher on. Remove the redundant initialization. Cleans up clang scan warning: drivers/block/loop.c:823:19: warning: Value stored to 'node' during its initialization is never read [deadcode.DeadStores] Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Link: https://lore.kernel.org/r/20220113001432.1331871-1-colin.i.king@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-01-12Merge tag 'for-5.17/drivers-2022-01-11' of git://git.kernel.dk/linux-blockLinus Torvalds1-56/+52
Pull block driver updates from Jens Axboe: - mtip32xx pci cleanups (Bjorn) - mtip32xx conversion to generic power management (Vaibhav) - rsxx pci powermanagement cleanups (Bjorn) - Remove the rsxx driver. This hardware never saw much adoption, and it's been end of lifed for a while. (Christoph) - MD pull request from Song: - REQ_NOWAIT support (Vishal Verma) - raid6 benchmark optimization (Dirk Müller) - Fix for acct bioset (Xiao Ni) - Clean up max_queued_requests (Mariusz Tkaczyk) - PREEMPT_RT optimization (Davidlohr Bueso) - Use default_groups in kobj_type (Greg Kroah-Hartman) - Use attribute groups in pktcdvd and rnbd (Greg) - NVMe pull request from Christoph: - increment request genctr on completion (Keith Busch, Geliang Tang) - add a 'iopolicy' module parameter (Hannes Reinecke) - print out valid arguments when reading from /dev/nvme-fabrics (Hannes Reinecke) - Use struct_group() in drbd (Kees) - null_blk fixes (Ming) - Get rid of congestion logic in pktcdvd (Neil) - Floppy ejection hang fix (Tasos) - Floppy max user request size fix (Xiongwei) - Loop locking fix (Tetsuo) * tag 'for-5.17/drivers-2022-01-11' of git://git.kernel.dk/linux-block: (32 commits) md: use default_groups in kobj_type md: Move alloc/free acct bioset in to personality lib/raid6: Use strict priority ranking for pq gen() benchmarking lib/raid6: skip benchmark of non-chosen xor_syndrome functions md: fix spelling of "its" md: raid456 add nowait support md: raid10 add nowait support md: raid1 add nowait support md: add support for REQ_NOWAIT md: drop queue limitation for RAID1 and RAID10 md/raid5: play nice with PREEMPT_RT block/rnbd-clt-sysfs: use default_groups in kobj_type pktcdvd: convert to use attribute groups block: null_blk: only set set->nr_maps as 3 if active poll_queues is > 0 nvme: add 'iopolicy' module parameter nvme: drop unused variable ctrl in nvme_setup_cmd nvme: increment request genctr on completion nvme-fabrics: print out valid arguments when reading from /dev/nvme-fabrics block: remove the rsxx driver rsxx: Drop PCI legacy power management ...
2022-01-12Merge tag 'for-5.17/block-2022-01-11' of git://git.kernel.dk/linux-blockLinus Torvalds1-5/+4
Pull block updates from Jens Axboe: - Unify where the struct request handling code is located in the blk-mq code (Christoph) - Header cleanups (Christoph) - Clean up the io_context handling code (Christoph, me) - Get rid of ->rq_disk in struct request (Christoph) - Error handling fix for add_disk() (Christoph) - request allocation cleanusp (Christoph) - Documentation updates (Eric, Matthew) - Remove trivial crypto unregister helper (Eric) - Reduce shared tag overhead (John) - Reduce poll_stats memory overhead (me) - Known indirect function call for dio (me) - Use atomic references for struct request (me) - Support request list issue for block and NVMe (me) - Improve queue dispatch pinning (Ming) - Improve the direct list issue code (Keith) - BFQ improvements (Jan) - Direct completion helper and use it in mmc block (Sebastian) - Use raw spinlock for the blktrace code (Wander) - fsync error handling fix (Ye) - Various fixes and cleanups (Lukas, Randy, Yang, Tetsuo, Ming, me) * tag 'for-5.17/block-2022-01-11' of git://git.kernel.dk/linux-block: (132 commits) MAINTAINERS: add entries for block layer documentation docs: block: remove queue-sysfs.rst docs: sysfs-block: document virt_boundary_mask docs: sysfs-block: document stable_writes docs: sysfs-block: fill in missing documentation from queue-sysfs.rst docs: sysfs-block: add contact for nomerges docs: sysfs-block: sort alphabetically docs: sysfs-block: move to stable directory block: don't protect submit_bio_checks by q_usage_counter block: fix old-style declaration nvme-pci: fix queue_rqs list splitting block: introduce rq_list_move block: introduce rq_list_for_each_safe macro block: move rq_list macros to blk-mq.h block: drop needless assignment in set_task_ioprio() block: remove unnecessary trailing '\' bio.h: fix kernel-doc warnings block: check minor range in device_add_disk() block: use "unsigned long" for blk_validate_block_size(). block: fix error unwinding in device_add_disk ...
2021-12-13loop: make autoclear operation asynchronousTetsuo Handa1-29/+36
syzbot is reporting circular locking problem at __loop_clr_fd() [1], for commit 87579e9b7d8dc36e ("loop: use worker per cgroup instead of kworker") is calling destroy_workqueue() with disk->open_mutex held. This circular dependency cannot be broken unless we call __loop_clr_fd() without holding disk->open_mutex. Therefore, defer __loop_clr_fd() from lo_release() to a WQ context. Link: https://syzkaller.appspot.com/bug?extid=643e4ce4b6ad1347d372 [1] Reported-by: syzbot <syzbot+643e4ce4b6ad1347d372@syzkaller.appspotmail.com> Suggested-by: Christoph Hellwig <hch@infradead.org> Cc: Jan Kara <jack@suse.cz> Tested-by: syzbot+643e4ce4b6ad1347d372@syzkaller.appspotmail.com Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/1ed7df28-ebd6-71fb-70e5-1c2972e05ddb@i-love.sakura.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29loop: Use pr_warn_once() for loop_control_remove() warningTetsuo Handa1-1/+1
kernel test robot reported that RCU stall via printk() flooding is possible [1] when stress testing. Link: https://lkml.kernel.org/r/20211129073709.GA18483@xsang-OptiPlex-9020 [1] Reported-by: kernel test robot <oliver.sang@intel.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29loop: don't hold lo_mutex during __loop_clr_fd()Tetsuo Handa1-33/+22
syzbot is reporting circular locking problem at __loop_clr_fd() [1], for commit 87579e9b7d8dc36e ("loop: use worker per cgroup instead of kworker") is calling destroy_workqueue() with lo->lo_mutex held. Since all functions where lo->lo_state matters are already checking lo->lo_state with lo->lo_mutex held (in order to avoid racing with e.g. ioctl(LOOP_CTL_REMOVE)), and __loop_clr_fd() can be called from either ioctl(LOOP_CLR_FD) xor close(), lo->lo_state == Lo_rundown is considered as an exclusive lock for __loop_clr_fd(). Therefore, hold lo->lo_mutex inside __loop_clr_fd() only when asserting/updating lo->lo_state. Since ioctl(LOOP_CLR_FD) depends on lo->lo_state == Lo_bound, a valid lo->lo_backing_file must have been assigned by ioctl(LOOP_SET_FD) or ioctl(LOOP_CONFIGURE). Thus, we can remove lo->lo_backing_file test, and convert __loop_clr_fd() into a void function. Link: https://syzkaller.appspot.com/bug?extid=63614029dfb79abd4383 [1] Reported-by: syzbot <syzbot+63614029dfb79abd4383@syzkaller.appspotmail.com> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/8ebe3b2e-8975-7f26-0620-7144a3b8b8cd@i-love.sakura.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: remove GENHD_FL_EXT_DEVTChristoph Hellwig1-1/+0
All modern drivers can support extra partitions using the extended dev_t. In fact except for the ioctl method drivers never even see partitions in normal operation. So remove the GENHD_FL_EXT_DEVT and allow extra partitions for all block devices that do support partitions, and require those that do not support partitions to explicit disallow them using GENHD_FL_NO_PART. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211122130625.1136848-12-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: rename GENHD_FL_NO_PART_SCAN to GENHD_FL_NO_PARTChristoph Hellwig1-4/+4
The GENHD_FL_NO_PART_SCAN controls more than just partitions canning, so rename it to GENHD_FL_NO_PART. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://lore.kernel.org/r/20211122130625.1136848-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-09Merge tag 'for-5.16/drivers-2021-11-09' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+0
Pull more block driver updates from Jens Axboe: - Last series adding error handling support for add_disk() in drivers. After this one, and once the SCSI side has been merged, we can finally annotate add_disk() as must_check. (Luis) - bcache fixes (Coly) - zram fixes (Ming) - ataflop locking fix (Tetsuo) - nbd fixes (Ye, Yu) - MD merge via Song - Cleanup (Yang) - sysfs fix (Guoqing) - Misc fixes (Geert, Wu, luo) * tag 'for-5.16/drivers-2021-11-09' of git://git.kernel.dk/linux-block: (34 commits) bcache: Revert "bcache: use bvec_virt" ataflop: Add missing semicolon to return statement floppy: address add_disk() error handling on probe ataflop: address add_disk() error handling on probe block: update __register_blkdev() probe documentation ataflop: remove ataflop_probe_lock mutex mtd/ubi/block: add error handling support for add_disk() block/sunvdc: add error handling support for add_disk() z2ram: add error handling support for add_disk() nvdimm/pmem: use add_disk() error handling nvdimm/pmem: cleanup the disk if pmem_release_disk() is yet assigned nvdimm/blk: add error handling support for add_disk() nvdimm/blk: avoid calling del_gendisk() on early failures nvdimm/btt: add error handling support for add_disk() nvdimm/btt: use goto error labels on btt_blk_init() loop: Remove duplicate assignments drbd: Fix double free problem in drbd_create_device nvdimm/btt: do not call del_gendisk() if not needed bcache: fix use-after-free problem in bcache_device_free() zram: replace fsync_bdev with sync_blockdev ...
2021-11-04loop: Remove duplicate assignmentsluo penghao1-1/+0
The assignment and operation there will be overwritten later, so it should be deleted. The clang_analyzer complains as follows: drivers/block/loop.c:2330:2 warning: Value stored to 'err' is never read change in v2: Repair the sending email box Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: luo penghao <luo.penghao@zte.com.cn> Link: https://lore.kernel.org/r/20211104064546.3074-1-luo.penghao@zte.com.cn Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-01Merge tag 'for-5.16/ki_complete-2021-10-29' of git://git.kernel.dk/linux-blockLinus Torvalds1-2/+2
Pull kiocb->ki_complete() cleanup from Jens Axboe: "This removes the res2 argument from kiocb->ki_complete(). Only the USB gadget code used it, everybody else passes 0. The USB guys checked the user gadget code they could find, and everybody just uses res as expected for the async interface" * tag 'for-5.16/ki_complete-2021-10-29' of git://git.kernel.dk/linux-block: fs: get rid of the res2 iocb->ki_complete argument usb: remove res2 argument from gadget code completions
2021-11-01Merge tag 'for-5.16/drivers-2021-10-29' of git://git.kernel.dk/linux-blockLinus Torvalds1-351/+33
Pull block driver updates from Jens Axboe: - paride driver cleanups (Christoph) - Remove cryptoloop support (Christoph) - null_blk poll support (me) - Now that add_disk() supports proper error handling, add it to various drivers (Luis) - Make ataflop actually work again (Michael) - s390 dasd fixes (Stefan, Heiko) - nbd fixes (Yu, Ye) - Remove redundant wq flush in mtip32xx (Christophe) - NVMe updates - fix a multipath partition scanning deadlock (Hannes Reinecke) - generate uevent once a multipath namespace is operational again (Hannes Reinecke) - support unique discovery controller NQNs (Hannes Reinecke) - fix use-after-free when a port is removed (Israel Rukshin) - clear shadow doorbell memory on resets (Keith Busch) - use struct_size (Len Baker) - add error handling support for add_disk (Luis Chamberlain) - limit the maximal queue size for RDMA controllers (Max Gurtovoy) - use a few more symbolic names (Max Gurtovoy) - fix error code in nvme_rdma_setup_ctrl (Max Gurtovoy) - add support for ->map_queues on FC (Saurav Kashyap) - support the current discovery subsystem entry (Hannes Reinecke) - use flex_array_size and struct_size (Len Baker) - bcache fixes (Christoph, Coly, Chao, Lin, Qing) - MD updates (Christoph, Guoqing, Xiao) - Misc fixes (Dan, Ding, Jiapeng, Shin'ichiro, Ye) * tag 'for-5.16/drivers-2021-10-29' of git://git.kernel.dk/linux-block: (117 commits) null_blk: Fix handling of submit_queues and poll_queues attributes block: ataflop: Fix warning comparing pointer to 0 bcache: replace snprintf in show functions with sysfs_emit bcache: move uapi header bcache.h to bcache code directory nvmet: use flex_array_size and struct_size nvmet: register discovery subsystem as 'current' nvmet: switch check for subsystem type nvme: add new discovery log page entry definitions block: ataflop: more blk-mq refactoring fixes block: remove support for cryptoloop and the xor transfer mtd: add add_disk() error handling rnbd: add error handling support for add_disk() um/drivers/ubd_kern: add error handling support for add_disk() m68k/emu/nfblock: add error handling support for add_disk() xen-blkfront: add error handling support for add_disk() bcache: add error handling support for add_disk() dm: add add_disk() error handling block: aoe: fixup coccinelle warnings nvmet: use struct_size over open coded arithmetic nvme: drop scan_lock and always kick requeue list when removing namespaces ...
2021-10-27loop: Use blk_validate_block_size() to validate block sizeXie Yongji1-15/+2
Remove loop_validate_block_size() and use the block layer helper to validate block size. Signed-off-by: Xie Yongji <xieyongji@bytedance.com> Link: https://lore.kernel.org/r/20211026144015.188-4-xieyongji@bytedance.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-25fs: get rid of the res2 iocb->ki_complete argumentJens Axboe1-2/+2
The second argument was only used by the USB gadget code, yet everyone pays the overhead of passing a zero to be passed into aio, where it ends up being part of the aio res2 value. Now that everybody is passing in zero, kill off the extra argument. Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-22block: remove support for cryptoloop and the xor transferChristoph Hellwig1-350/+26
Support for cyrptoloop has been officially marked broken and deprecated in favor of dm-crypt (which supports the same broken algorithms if needed) in Linux 2.6.4 (released in March 2004), and support for it has been entirely removed from losetup in util-linux 2.23 (released in April 2013). The XOR transfer has never been more than a toy to demonstrate the transfer in the bad old times of crypto export restrictions. Remove them as they have some nasty interactions with loop device life times due to the iteration over all loop devices in loop_unregister_transfer. Suggested-by: Milan Broz <gmazyland@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211019075639.2333969-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-21loop: Remove the unnecessary bdev checks and unused bdev variableXie Yongji1-6/+3
The lo->lo_device can't be null if the lo->lo_backing_file is set. So let's remove the unnecessary bdev checks and the entire bdev variable in __loop_clr_fd() since the lo->lo_backing_file is already checked before. Signed-off-by: Xie Yongji <xieyongji@bytedance.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210922123711.187-4-xieyongji@bytedance.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-21loop: Use invalidate_disk() helper to invalidate gendiskXie Yongji1-5/+1
Use invalidate_disk() helper to simplify the code for gendisk invalidation. Signed-off-by: Xie Yongji <xieyongji@bytedance.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210922123711.187-3-xieyongji@bytedance.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18loop: add error handling support for add_disk()Luis Chamberlain1-1/+7
We never checked for errors on add_disk() as this function returned void. Now that this is fixed, use the shiny new error handling. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-09-04loop: reduce the loop_ctl_mutex scopeTetsuo Handa1-26/+49
syzbot is reporting circular locking problem at __loop_clr_fd() [1], for commit a160c6159d4a0cf8 ("block: add an optional probe callback to major_names") is calling the module's probe function with major_names_lock held. Fortunately, since commit 990e78116d38059c ("block: loop: fix deadlock between open and remove") stopped holding loop_ctl_mutex in lo_open(), current role of loop_ctl_mutex is to serialize access to loop_index_idr and loop_add()/loop_remove(); in other words, management of id for IDR. To avoid holding loop_ctl_mutex during whole add/remove operation, use a bool flag to indicate whether the loop device is ready for use. loop_unregister_transfer() which is called from cleanup_cryptoloop() currently has possibility of use-after-free problem due to lack of serialization between kfree() from loop_remove() from loop_control_remove() and mutex_lock() from unregister_transfer_cb(). But since lo->lo_encryption should be already NULL when this function is called due to module unload, and commit 222013f9ac30b9ce ("cryptoloop: add a deprecation warning") indicates that we will remove this function shortly, this patch updates this function to emit warning instead of checking lo->lo_encryption. Holding loop_ctl_mutex in loop_exit() is pointless, for all users must close /dev/loop-control and /dev/loop$num (in order to drop module's refcount to 0) before loop_exit() starts, and nobody can open /dev/loop-control or /dev/loop$num afterwards. Link: https://syzkaller.appspot.com/bug?id=7bb10e8b62f83e4d445cdf4c13d69e407e629558 [1] Reported-by: syzbot <syzbot+f61766d5763f9e7a118f@syzkaller.appspotmail.com> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/adb1e792-fc0e-ee81-7ea0-0906fc36419d@i-love.sakura.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-05loop: Select I/O scheduler 'none' from inside add_disk()Bart Van Assche1-1/+2
We noticed that the user interface of Android devices becomes very slow under memory pressure. This is because Android uses the zram driver on top of the loop driver for swapping, because under memory pressure the swap code alternates reads and writes quickly, because mq-deadline is the default scheduler for loop devices and because mq-deadline delays writes by five seconds for such a workload with default settings. Fix this by making the kernel select I/O scheduler 'none' from inside add_disk() for loop devices. This default can be overridden at any time from user space, e.g. via a udev rule. This approach has an advantage compared to changing the I/O scheduler from userspace from 'mq-deadline' into 'none', namely that synchronize_rcu() does not get called. This patch changes the default I/O scheduler for loop devices from 'mq-deadline' into 'none'. Additionally, this patch reduces the Android boot time on my test setup with 0.5 seconds compared to configuring the loop I/O scheduler from user space. Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Martijn Coenen <maco@android.com> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20210805174200.3250718-3-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-02loop: raise media_change eventMatteo Croce1-0/+5
Make the loop device raise a DISK_MEDIA_CHANGE event on attach or detach. # udevadm monitor -up |grep -e DISK_MEDIA_CHANGE -e DEVNAME & # losetup -f zero [ 7.454235] loop0: detected capacity change from 0 to 16384 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop0 DEVNAME=/dev/loop0 DEVNAME=/dev/loop0 # losetup -f zero [ 10.205245] loop1: detected capacity change from 0 to 16384 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop1 DEVNAME=/dev/loop1 DEVNAME=/dev/loop1 # losetup -f zero2 [ 13.532368] loop2: detected capacity change from 0 to 40960 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop2 DEVNAME=/dev/loop2 # losetup -D DEVNAME=/dev/loop1 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop1 DEVNAME=/dev/loop2 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop2 DEVNAME=/dev/loop0 DISK_MEDIA_CHANGE=1 DEVNAME=/dev/loop0 Signed-off-by: Matteo Croce <mcroce@microsoft.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Luca Boccassi <bluca@debian.org> Link: https://lore.kernel.org/r/20210712230530.29323-7-mcroce@linux.microsoft.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-02loop: don't grab a reference to the block deviceChristoph Hellwig1-5/+0
The whole device block device won't be removed while the disk is still alive, so don't bother to grab a reference to it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Ming Lei <ming.lei@rehat.com> Reviewed-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com> Link: https://lore.kernel.org/r/20210722075402.983367-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-23loop: reintroduce global lock for safe loop_validate_file() traversalTetsuo Handa1-31/+97
Commit 6cc8e7430801fa23 ("loop: scale loop device by introducing per device lock") re-opened a race window for NULL pointer dereference at loop_validate_file() where commit 310ca162d779efee ("block/loop: Use global lock for ioctl() operation.") has closed. Although we need to guarantee that other loop devices will not change during traversal, we can't take remote "struct loop_device"->lo_mutex inside loop_validate_file() in order to avoid AB-BA deadlock. Therefore, introduce a global lock dedicated for loop_validate_file() which is conditionally taken before local "struct loop_device"->lo_mutex is taken. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Fixes: 6cc8e7430801fa23 ("loop: scale loop device by introducing per device lock") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-02loop: remove unused variable in loop_set_status()Tetsuo Handa1-2/+0
Commit 0384264ea8a39bd9 ("block: pass a gendisk to bdev_disk_changed") changed to pass lo->lo_disk instead of lo->lo_device. Fixes: 0384264ea8a3 ("block: pass a gendisk to bdev_disk_changed") Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Link: https://lore.kernel.org/r/20210702152714.7978-1-penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-01loop: rewrite loop_exit using idr_for_each_entryChristoph Hellwig1-9/+5
Use idr_for_each_entry to simplify removing all devices. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210623145908.92973-10-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-01loop: split loop_lookupChristoph Hellwig1-45/+12
loop_lookup has two callers - one wants to do the a find by index and the other wants any unbound loop device. Open code the respective functionality in each caller. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210623145908.92973-9-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-01loop: don't allow deleting an unspecified loop deviceChristoph Hellwig1-0/+5
Passing a negative index to loop_lookup while return any unbound device. Doing that for a delete does not make much sense, so add check to explicitly reject that case. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210623145908.92973-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-01loop: move loop_ctl_mutex locking into loop_addChristoph Hellwig1-24/+13
Move acquiring and releasing loop_ctl_mutex from the callers into loop_add. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210623145908.92973-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-01loop: split loop_control_ioctlChristoph Hellwig1-33/+60
Split loop_control_ioctl into a helper for each command. This keeps the code nicely separated for the upcoming locking changes. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210623145908.92973-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-01loop: don't call loop_lookup before adding a loop deviceChristoph Hellwig1-8/+1
loop_add returns the right error if the slot wasn't available. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20210623145908.92973-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-01loop: remove the l argument to loop_addChristoph Hellwig1-7/+5
None of the callers cares about the allocated struct loop_device. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210623145908.92973-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-01loop: reduce loop_ctl_mutex coverage in loop_exitChristoph Hellwig1-2/+3
loop_ctl_mutex is only needed to iterate the IDR for removing the loop devices, so reduce the coverage. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210623145908.92973-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-07-01loop: reorder loop_exitChristoph Hellwig1-5/+2
Unregister the misc and blockdevice first to prevent further access, and only then iterate to remove the devices. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210623145908.92973-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-30Merge tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-blockLinus Torvalds1-0/+1
Pull block driver updates from Jens Axboe: "Pretty calm round, mostly just NVMe and a bit of MD: - NVMe updates (via Christoph) - improve the APST configuration algorithm (Alexey Bogoslavsky) - look for StorageD3Enable on companion ACPI device (Mario Limonciello) - allow selecting the network interface for TCP connections (Martin Belanger) - misc cleanups (Amit Engel, Chaitanya Kulkarni, Colin Ian King, Christoph) - move the ACPI StorageD3 code to drivers/acpi/ and add quirks for certain AMD CPUs (Mario Limonciello) - zoned device support for nvmet (Chaitanya Kulkarni) - fix the rules for changing the serial number in nvmet (Noam Gottlieb) - various small fixes and cleanups (Dan Carpenter, JK Kim, Chaitanya Kulkarni, Hannes Reinecke, Wesley Sheng, Geert Uytterhoeven, Daniel Wagner) - MD updates (Via Song) - iostats rewrite (Guoqing Jiang) - raid5 lock contention optimization (Gal Ofri) - Fall through warning fix (Gustavo) - Misc fixes (Gustavo, Jiapeng)" * tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-block: (78 commits) nvmet: use NVMET_MAX_NAMESPACES to set nn value loop: Fix missing discard support when using LOOP_CONFIGURE nvme.h: add missing nvme_lba_range_type endianness annotations nvme: remove zeroout memset call for struct nvme-pci: remove zeroout memset call for struct nvmet: remove zeroout memset call for struct nvmet: add ZBD over ZNS backend support nvmet: add Command Set Identifier support nvmet: add nvmet_req_bio put helper for backends nvmet: add req cns error complete helper block: export blk_next_bio() nvmet: remove local variable nvmet: use nvme status value directly nvmet: use u32 type for the local variable nsid nvmet: use u32 for nvmet_subsys max_nsid nvmet: use req->cmd directly in file-ns fast path nvmet: use req->cmd directly in bdev-ns fast path nvmet: make ver stable once connection established nvmet: allow mn change if subsys not discovered nvmet: make sn stable once connection was established ...
2021-06-30Merge tag 'for-5.14/block-2021-06-29' of git://git.kernel.dk/linux-blockLinus Torvalds1-27/+19
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() ...
2021-06-29loop: charge i/o to mem and blk cgDan Schatzberg1-20/+41
The current code only associates with the existing blkcg when aio is used to access the backing file. This patch covers all types of i/o to the backing file and also associates the memcg so if the backing file is on tmpfs, memory is charged appropriately. This patch also exports cgroup_get_e_css and int_active_memcg so it can be used by the loop module. Link: https://lkml.kernel.org/r/20210610173944.1203706-4-schatzberg.dan@gmail.com Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Jens Axboe <axboe@kernel.dk> Cc: Chris Down <chris@chrisdown.name> Cc: Michal Hocko <mhocko@suse.com> Cc: Ming Lei <ming.lei@redhat.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29loop: use worker per cgroup instead of kworkerDan Schatzberg1-30/+179
Patch series "Charge loop device i/o to issuing cgroup", v14. The loop device runs all i/o to the backing file on a separate kworker thread which results in all i/o being charged to the root cgroup. This allows a loop device to be used to trivially bypass resource limits and other policy. This patch series fixes this gap in accounting. A simple script to demonstrate this behavior on cgroupv2 machine: ''' #!/bin/bash set -e CGROUP=/sys/fs/cgroup/test.slice LOOP_DEV=/dev/loop0 if [[ ! -d $CGROUP ]] then sudo mkdir $CGROUP fi grep oom_kill $CGROUP/memory.events # Set a memory limit, write more than that limit to tmpfs -> OOM kill sudo unshare -m bash -c " echo \$\$ > $CGROUP/cgroup.procs; echo 0 > $CGROUP/memory.swap.max; echo 64M > $CGROUP/memory.max; mount -t tmpfs -o size=512m tmpfs /tmp; dd if=/dev/zero of=/tmp/file bs=1M count=256" || true grep oom_kill $CGROUP/memory.events # Set a memory limit, write more than that limit through loopback # device -> no OOM kill sudo unshare -m bash -c " echo \$\$ > $CGROUP/cgroup.procs; echo 0 > $CGROUP/memory.swap.max; echo 64M > $CGROUP/memory.max; mount -t tmpfs -o size=512m tmpfs /tmp; truncate -s 512m /tmp/backing_file losetup $LOOP_DEV /tmp/backing_file dd if=/dev/zero of=$LOOP_DEV bs=1M count=256; losetup -D $LOOP_DEV" || true grep oom_kill $CGROUP/memory.events ''' Naively charging cgroups could result in priority inversions through the single kworker thread in the case where multiple cgroups are reading/writing to the same loop device. This patch series does some minor modification to the loop driver so that each cgroup can make forward progress independently to avoid this inversion. With this patch series applied, the above script triggers OOM kills when writing through the loop device as expected. This patch (of 3): Existing uses of loop device may have multiple cgroups reading/writing to the same device. Simply charging resources for I/O to the backing file could result in priority inversion where one cgroup gets synchronously blocked, holding up all other I/O to the loop device. In order to avoid this priority inversion, we use a single workqueue where each work item is a "struct loop_worker" which contains a queue of struct loop_cmds to issue. The loop device maintains a tree mapping blk css_id -> loop_worker. This allows each cgroup to independently make forward progress issuing I/O to the backing file. There is also a single queue for I/O associated with the rootcg which can be used in cases of extreme memory shortage where we cannot allocate a loop_worker. The locking for the tree and queues is fairly heavy handed - we acquire a per-loop-device spinlock any time either is accessed. The existing implementation serializes all I/O through a single thread anyways, so I don't believe this is any worse. [colin.king@canonical.com: fixes] Link: https://lkml.kernel.org/r/20210610173944.1203706-1-schatzberg.dan@gmail.com Link: https://lkml.kernel.org/r/20210610173944.1203706-2-schatzberg.dan@gmail.com Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Acked-by: Jens Axboe <axboe@kernel.dk> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Chris Down <chris@chrisdown.name> Cc: Shakeel Butt <shakeelb@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-24block: pass a gendisk to bdev_disk_changedChristoph Hellwig1-11/+10
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>
2021-06-18loop: Fix missing discard support when using LOOP_CONFIGUREKristian Klausen1-0/+1
Without calling loop_config_discard() the discard flag and parameters aren't set/updated for the loop device and worst-case they could indicate discard support when it isn't the case (ex: if the LOOP_SET_STATUS ioctl was used with a different file prior to LOOP_CONFIGURE). Cc: <stable@vger.kernel.org> # 5.8.x- Fixes: 3448914e8cc5 ("loop: Add LOOP_CONFIGURE ioctl") Signed-off-by: Kristian Klausen <kristian@klausen.dk> Link: https://lore.kernel.org/r/20210618115157.31452-1-kristian@klausen.dk Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-16loop: fix order of cleaning up the queue and freeing the tagsetChristoph Hellwig1-1/+1
We must release the queue before freeing the tagset. Fixes: 1c99502fae35 ("loop: use blk_mq_alloc_disk and blk_cleanup_disk") Reported-by: Bruno Goncalves <bgoncalv@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-12Merge tag 'block-5.13-2021-06-12' of git://git.kernel.dk/linux-blockLinus Torvalds1-18/+7
Pull block fixes from Jens Axboe: "A few fixes that should go into 5.13: - Fix a regression deadlock introduced in this release between open and remove of a bdev (Christoph) - Fix an async_xor md regression in this release (Xiao) - Fix bcache oversized read issue (Coly)" * tag 'block-5.13-2021-06-12' of git://git.kernel.dk/linux-block: block: loop: fix deadlock between open and remove async_xor: check src_offs is not NULL before updating it bcache: avoid oversized read request in cache missing code path bcache: remove bcache device self-defined readahead
2021-06-11loop: use blk_mq_alloc_disk and blk_cleanup_diskChristoph Hellwig1-13/+6
Use blk_mq_alloc_disk and blk_cleanup_disk to simplify the gendisk and request_queue allocation. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210602065345.355274-19-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-11block: loop: fix deadlock between open and removeChristoph Hellwig1-18/+7
Commit c76f48eb5c08 ("block: take bd_mutex around delete_partitions in del_gendisk") adds disk->part0->bd_mutex in del_gendisk(), this way causes the following AB/BA deadlock between removing loop and opening loop: 1) loop_control_ioctl(LOOP_CTL_REMOVE) -> mutex_lock(&loop_ctl_mutex) -> del_gendisk -> mutex_lock(&disk->part0->bd_mutex) 2) blkdev_get_by_dev -> mutex_lock(&disk->part0->bd_mutex) -> lo_open -> mutex_lock(&loop_ctl_mutex) Add a new Lo_deleting state to remove the need for clearing ->private_data and thus holding loop_ctl_mutex in the ioctl LOOP_CTL_REMOVE path. Based on an analysis and earlier patch from Ming Lei <ming.lei@redhat.com>. Reported-by: Colin Ian King <colin.king@canonical.com> Fixes: c76f48eb5c08 ("block: take bd_mutex around delete_partitions in del_gendisk") Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20210605140950.5800-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-01block: move bd_mutex to struct gendiskChristoph Hellwig1-7/+7
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>
2021-05-07include: remove pagemap.h from blkdev.hMatthew Wilcox (Oracle)1-0/+1
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>
2021-02-28Merge tag 'block-5.12-2021-02-27' of git://git.kernel.dk/linux-blockLinus Torvalds1-0/+3
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() ...
2021-02-27Merge branch 'work.misc' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "Assorted stuff pile - no common topic here" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: whack-a-mole: don't open-code iminor/imajor 9p: fix misuse of sscanf() in v9fs_stat2inode() audit_alloc_mark(): don't open-code ERR_CAST() fs/inode.c: make inode_init_always() initialize i_ino to 0 vfs: don't unnecessarily clone write access for writable fds
2021-02-23whack-a-mole: don't open-code iminor/imajorAl Viro1-1/+1
several instances creeped back into the tree... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
generated by cgit v1.2.3 (git 2.39.0) at 2024-07-27 19:38:28 +0300