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2024-05-30block: Fix zone write plugging handling of devices with a runt zoneDamien Le Moal
A zoned device may have a last sequential write required zone that is smaller than other zones. However, all tests to check if a zone write plug write offset exceeds the zone capacity use the same capacity value stored in the gendisk zone_capacity field. This is incorrect for a zoned device with a last runt (smaller) zone. Add the new field last_zone_capacity to struct gendisk to store the capacity of the last zone of the device. blk_revalidate_seq_zone() and blk_revalidate_conv_zone() are both modified to get this value when disk_zone_is_last() returns true. Similarly to zone_capacity, the value is first stored using the last_zone_capacity field of struct blk_revalidate_zone_args. Once zone revalidation of all zones is done, this is used to set the gendisk last_zone_capacity field. The checks to determine if a zone is full or if a sector offset in a zone exceeds the zone capacity in disk_should_remove_zone_wplug(), disk_zone_wplug_abort_unaligned(), blk_zone_write_plug_init_request(), and blk_zone_wplug_prepare_bio() are modified to use the new helper functions disk_zone_is_full() and disk_zone_wplug_is_full(). disk_zone_is_full() uses the zone index to determine if the zone being tested is the last one of the disk and uses the either the disk zone_capacity or last_zone_capacity accordingly. Fixes: dd291d77cc90 ("block: Introduce zone write plugging") Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Niklas Cassel <cassel@kernel.org> Link: https://lore.kernel.org/r/20240530054035.491497-4-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-05-21Merge tag 'pull-bd_flags-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull bdev flags update from Al Viro: "Compactifying bdev flags. We can easily have up to 24 flags with sane atomicity, _without_ pushing anything out of the first cacheline of struct block_device" * tag 'pull-bd_flags-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: bdev: move ->bd_make_it_fail to ->__bd_flags bdev: move ->bd_ro_warned to ->__bd_flags bdev: move ->bd_has_subit_bio to ->__bd_flags bdev: move ->bd_write_holder into ->__bd_flags bdev: move ->bd_read_only to ->__bd_flags bdev: infrastructure for flags wrapper for access to ->bd_partno Use bdev_is_paritition() instead of open-coding it
2024-05-21Merge tag 'pull-bd_inode-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull bdev bd_inode updates from Al Viro: "Replacement of bdev->bd_inode with sane(r) set of primitives by me and Yu Kuai" * tag 'pull-bd_inode-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: RIP ->bd_inode dasd_format(): killing the last remaining user of ->bd_inode nilfs_attach_log_writer(): use ->bd_mapping->host instead of ->bd_inode block/bdev.c: use the knowledge of inode/bdev coallocation gfs2: more obvious initializations of mapping->host fs/buffer.c: massage the remaining users of ->bd_inode to ->bd_mapping blk_ioctl_{discard,zeroout}(): we only want ->bd_inode->i_mapping here... grow_dev_folio(): we only want ->bd_inode->i_mapping there use ->bd_mapping instead of ->bd_inode->i_mapping block_device: add a pointer to struct address_space (page cache of bdev) missing helpers: bdev_unhash(), bdev_drop() block: move two helpers into bdev.c block2mtd: prevent direct access of bd_inode dm-vdo: use bdev_nr_bytes(bdev) instead of i_size_read(bdev->bd_inode) blkdev_write_iter(): saner way to get inode and bdev bcachefs: remove dead function bdev_sectors() ext4: remove block_device_ejected() erofs_buf: store address_space instead of inode erofs: switch erofs_bread() to passing offset instead of block number
2024-05-21Merge tag 'pull-set_blocksize' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs blocksize updates from Al Viro: "This gets rid of bogus set_blocksize() uses, switches it over to be based on a 'struct file *' and verifies that the caller has the device opened exclusively" * tag 'pull-set_blocksize' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: make set_blocksize() fail unless block device is opened exclusive set_blocksize(): switch to passing struct file * btrfs_get_bdev_and_sb(): call set_blocksize() only for exclusive opens swsusp: don't bother with setting block size zram: don't bother with reopening - just use O_EXCL for open swapon(2): open swap with O_EXCL swapon(2)/swapoff(2): don't bother with block size pktcdvd: sort set_blocksize() calls out bcache_register(): don't bother with set_blocksize()
2024-05-14Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds
Pull SCSI updates from James Bottomley: "Updates to the usual drivers (ufs, lpfc, qla2xxx, mpi3mr, libsas). The major update (which causes a conflict with block, see below) is Christoph removing the queue limits and their associated block helpers. The remaining patches are assorted minor fixes and deprecated function updates plus a bit of constification" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (141 commits) scsi: mpi3mr: Sanitise num_phys scsi: lpfc: Copyright updates for 14.4.0.2 patches scsi: lpfc: Update lpfc version to 14.4.0.2 scsi: lpfc: Add support for 32 byte CDBs scsi: lpfc: Change lpfc_hba hba_flag member into a bitmask scsi: lpfc: Introduce rrq_list_lock to protect active_rrq_list scsi: lpfc: Clear deferred RSCN processing flag when driver is unloading scsi: lpfc: Update logging of protection type for T10 DIF I/O scsi: lpfc: Change default logging level for unsolicited CT MIB commands scsi: target: Remove unused list 'device_list' scsi: iscsi: Remove unused list 'connlist_err' scsi: ufs: exynos: Add support for Tensor gs101 SoC scsi: ufs: exynos: Add some pa_dbg_ register offsets into drvdata scsi: ufs: exynos: Allow max frequencies up to 267Mhz scsi: ufs: exynos: Add EXYNOS_UFS_OPT_TIMER_TICK_SELECT option scsi: ufs: exynos: Add EXYNOS_UFS_OPT_UFSPR_SECURE option scsi: ufs: dt-bindings: exynos: Add gs101 compatible scsi: qla2xxx: Fix debugfs output for fw_resource_count scsi: qedf: Ensure the copied buf is NUL terminated scsi: bfa: Ensure the copied buf is NUL terminated ...
2024-05-13Merge tag 'for-6.10/block-20240511' of git://git.kernel.dk/linuxLinus Torvalds
Pull block updates from Jens Axboe: - Add a partscan attribute in sysfs, fixing an issue with systemd relying on an internal interface that went away. - Attempt #2 at making long running discards interruptible. The previous attempt went into 6.9, but we ended up mostly reverting it as it had issues. - Remove old ida_simple API in bcache - Support for zoned write plugging, greatly improving the performance on zoned devices. - Remove the old throttle low interface, which has been experimental since 2017 and never made it beyond that and isn't being used. - Remove page->index debugging checks in brd, as it hasn't caught anything and prepares us for removing in struct page. - MD pull request from Song - Don't schedule block workers on isolated CPUs * tag 'for-6.10/block-20240511' of git://git.kernel.dk/linux: (84 commits) blk-throttle: delay initialization until configuration blk-throttle: remove CONFIG_BLK_DEV_THROTTLING_LOW block: fix that util can be greater than 100% block: support to account io_ticks precisely block: add plug while submitting IO bcache: fix variable length array abuse in btree_iter bcache: Remove usage of the deprecated ida_simple_xx() API md: Revert "md: Fix overflow in is_mddev_idle" blk-lib: check for kill signal in ioctl BLKDISCARD block: add a bio_await_chain helper block: add a blk_alloc_discard_bio helper block: add a bio_chain_and_submit helper block: move discard checks into the ioctl handler block: remove the discard_granularity check in __blkdev_issue_discard block/ioctl: prefer different overflow check null_blk: Fix the WARNING: modpost: missing MODULE_DESCRIPTION() block: fix and simplify blkdevparts= cmdline parsing block: refine the EOF check in blkdev_iomap_begin block: add a partscan sysfs attribute for disks block: add a disk_has_partscan helper ...
2024-05-07md: Revert "md: Fix overflow in is_mddev_idle"Li Nan
This reverts commit 3f9f231236ce7e48780d8a4f1f8cb9fae2df1e4e. Using 64bit for 'sync_io' is unnecessary from the gendisk side. This overflow will not cause any functional impact, except for a UBSAN warning. Solving this overflow requires introducing additional calculations and checks which are not necessary. So just keep using 32bit for 'sync_io'. Signed-off-by: Li Nan <linan122@huawei.com> Link: https://lore.kernel.org/r/20240507023103.781816-1-linan666@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-05-03block: add a disk_has_partscan helperChristoph Hellwig
Add a helper to check if partition scanning is enabled instead of open coding the check in a few places. This now always checks for the hidden flag even if all but one of the callers are never reachable for hidden gendisks. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240502130033.1958492-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-05-03block: move two helpers into bdev.cYu Kuai
disk_live() and block_size() access bd_inode directly, prepare to remove the field bd_inode from block_device, and only access bd_inode in block layer. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Link: https://lore.kernel.org/r/20240411145346.2516848-8-viro@zeniv.linux.org.uk Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-05-02bdev: move ->bd_read_only to ->__bd_flagsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-05-02bdev: infrastructure for flagsAl Viro
Replace bd_partno with a 32bit field (__bd_flags). The lower 8 bits contain the partition number, the upper 24 are for flags. Helpers: bdev_{test,set,clear}_flag(bdev, flag), with atomic_or() and atomic_andnot() used to set/clear. NOTE: this commit does not actually move any flags over there - they are still bool fields. As the result, it shifts the fields wrt cacheline boundaries; that's going to be restored once the first 3 flags are dealt with. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-05-02wrapper for access to ->bd_partnoAl Viro
On the next step it's going to get folded into a field where flags will go. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-05-02set_blocksize(): switch to passing struct file *Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-04-25Merge tag 'md-6.10-20240425' of ↵Jens Axboe
https://git.kernel.org/pub/scm/linux/kernel/git/song/md into for-6.10/block Pull MD fixes from Song: "These changes contain various fixes by Yu Kuai, Li Nan, and Florian-Ewald Mueller." * tag 'md-6.10-20240425' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md: md: don't account sync_io if iostats of the disk is disabled md: Fix overflow in is_mddev_idle md: add check for sleepers in md_wakeup_thread() md/raid5: fix deadlock that raid5d() wait for itself to clear MD_SB_CHANGE_PENDING
2024-04-23block: use a per disk workqueue for zone write pluggingDamien Le Moal
A zone write plug BIO work function blk_zone_wplug_bio_work() calls submit_bio_noacct_nocheck() to execute the next unplugged BIO. This function may block. So executing zone plugs BIO works using the block layer global kblockd workqueue can potentially lead to preformance or latency issues as the number of concurrent work for a workqueue is limited to WQ_DFL_ACTIVE (256). 1) For a system with a large number of zoned disks, issuing write requests to otherwise unused zones may be delayed wiating for a work thread to become available. 2) Requeue operations which use kblockd but are independent of zone write plugging may alsoi end up being delayed. To avoid these potential performance issues, create a workqueue per zoned device to execute zone plugs BIO work. The workqueue max active parameter is set to the maximum number of zone write plugs allocated with the zone write plug mempool. This limit is equal to the maximum number of open zones of the disk and defaults to 128 for disks that do not have a limit on the number of open zones. Fixes: dd291d77cc90 ("block: Introduce zone write plugging") Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240420075811.1276893-3-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-20Merge tag 'block-6.9-20240420' of git://git.kernel.dk/linuxLinus Torvalds
Pull block fixes from Jens Axboe: "Just two minor fixes that should go into the 6.9 kernel release, one fixing a regression with partition scanning errors, and one fixing a WARN_ON() that can get triggered if we race with a timer" * tag 'block-6.9-20240420' of git://git.kernel.dk/linux: blk-iocost: do not WARN if iocg was already offlined block: propagate partition scanning errors to the BLKRRPART ioctl
2024-04-18block: propagate partition scanning errors to the BLKRRPART ioctlChristoph Hellwig
Commit 4601b4b130de ("block: reopen the device in blkdev_reread_part") lost the propagation of I/O errors from the low-level read of the partition table to the user space caller of the BLKRRPART. Apparently some user space relies on, so restore the propagation. This isn't exactly pretty as other block device open calls explicitly do not are about these errors, so add a new BLK_OPEN_STRICT_SCAN to opt into the error propagation. Fixes: 4601b4b130de ("block: reopen the device in blkdev_reread_part") Reported-by: Saranya Muruganandam <saranyamohan@google.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Link: https://lore.kernel.org/r/20240417144743.2277601-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-17block: Do not special-case plugging of zone write operationsDamien Le Moal
With the block layer zone write plugging being automatically done for any write operation to a zone of a zoned block device, a regular request plugging handled through current->plug can only ever see at most a single write request per zone. In such case, any potential reordering of the plugged requests will be harmless. We can thus remove the special casing for write operations to zones and have these requests plugged as well. This allows removing the function blk_mq_plug and instead directly using current->plug where needed. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Tested-by: Dennis Maisenbacher <dennis.maisenbacher@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20240408014128.205141-29-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-17block: Remove zone write lockingDamien Le Moal
Zone write locking is now unused and replaced with zone write plugging. Remove all code that was implementing zone write locking, that is, the various helper functions controlling request zone write locking and the gendisk attached zone bitmaps. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Tested-by: Dennis Maisenbacher <dennis.maisenbacher@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20240408014128.205141-27-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-17block: Remove elevator required featuresDamien Le Moal
The only elevator feature ever implemented is ELEVATOR_F_ZBD_SEQ_WRITE for signaling that a scheduler implements zone write locking to tightly control the dispatching order of write operations to zoned block devices. With the removal of zone write locking support in mq-deadline and the reliance of all block device drivers on the block layer zone write plugging to control ordering of write operations to zones, the elevator feature ELEVATOR_F_ZBD_SEQ_WRITE is completely unused. Remove it, and also remove the now unused code for filtering the possible schedulers for a block device based on required features. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Tested-by: Dennis Maisenbacher <dennis.maisenbacher@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20240408014128.205141-23-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-17block: Simplify blk_revalidate_disk_zones() interfaceDamien Le Moal
The only user of blk_revalidate_disk_zones() second argument was the SCSI disk driver (sd). Now that this driver does not require this update_driver_data argument, remove it to simplify the interface of blk_revalidate_disk_zones(). Also update the function kdoc comment to be more accurate (i.e. there is no gendisk ->revalidate method). Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Tested-by: Dennis Maisenbacher <dennis.maisenbacher@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20240408014128.205141-21-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-17block: Allow zero value of max_zone_append_sectors queue limitDamien Le Moal
In preparation for adding a generic zone append emulation using zone write plugging, allow device drivers supporting zoned block device to set a the max_zone_append_sectors queue limit of a device to 0 to indicate the lack of native support for zone append operations and that the block layer should emulate these operations using regular write operations. blk_queue_max_zone_append_sectors() is modified to allow passing 0 as the max_zone_append_sectors argument. The function queue_max_zone_append_sectors() is also modified to ensure that the minimum of the max_hw_sectors and chunk_sectors limit is used whenever the max_zone_append_sectors limit is 0. This minimum is consistent with the value set for the max_zone_append_sectors limit by the function blk_validate_zoned_limits() when limits for a queue are validated. The helper functions queue_emulates_zone_append() and bdev_emulates_zone_append() are added to test if a queue (or block device) emulates zone append operations. In order for blk_revalidate_disk_zones() to accept zoned block devices relying on zone append emulation, the direct check to the max_zone_append_sectors queue limit of the disk is replaced by a check using the value returned by queue_max_zone_append_sectors(). Similarly, queue_zone_append_max_show() is modified to use the same accessor so that the sysfs attribute advertizes the non-zero limit that will be used, regardless if it is for native or emulated commands. For stacking drivers, a top device should not need to care if the underlying devices have native or emulated zone append operations. blk_stack_limits() is thus modified to set the top device max_zone_append_sectors limit using the new accessor queue_limits_max_zone_append_sectors(). queue_max_zone_append_sectors() is modified to use this function as well. Stacking drivers that require zone append emulation, e.g. dm-crypt, can still request this feature by calling blk_queue_max_zone_append_sectors() with a 0 limit. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Tested-by: Dennis Maisenbacher <dennis.maisenbacher@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20240408014128.205141-10-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-17block: Introduce zone write pluggingDamien Le Moal
Zone write plugging implements a per-zone "plug" for write operations to control the submission and execution order of write operations to sequential write required zones of a zoned block device. Per-zone plugging guarantees that at any time there is at most only one write request per zone being executed. This mechanism is intended to replace zone write locking which implements a similar per-zone write throttling at the scheduler level, but is implemented only by mq-deadline. Unlike zone write locking which operates on requests, zone write plugging operates on BIOs. A zone write plug is simply a BIO list that is atomically manipulated using a spinlock and a kblockd submission work. A write BIO to a zone is "plugged" to delay its execution if a write BIO for the same zone was already issued, that is, if a write request for the same zone is being executed. The next plugged BIO is unplugged and issued once the write request completes. This mechanism allows to: - Untangle zone write ordering from block IO schedulers. This allows removing the restriction on using mq-deadline for writing to zoned block devices. Any block IO scheduler, including "none" can be used. - Zone write plugging operates on BIOs instead of requests. Plugged BIOs waiting for execution thus do not hold scheduling tags and thus are not preventing other BIOs from executing (reads or writes to other zones). Depending on the workload, this can significantly improve the device use (higher queue depth operation) and performance. - Both blk-mq (request based) zoned devices and BIO-based zoned devices (e.g. device mapper) can use zone write plugging. It is mandatory for the former but optional for the latter. BIO-based drivers can use zone write plugging to implement write ordering guarantees, or the drivers can implement their own if needed. - The code is less invasive in the block layer and is mostly limited to blk-zoned.c with some small changes in blk-mq.c, blk-merge.c and bio.c. Zone write plugging is implemented using struct blk_zone_wplug. This structure includes a spinlock, a BIO list and a work structure to handle the submission of plugged BIOs. Zone write plugs structures are managed using a per-disk hash table. Plugging of zone write BIOs is done using the function blk_zone_write_plug_bio() which returns false if a BIO execution does not need to be delayed and true otherwise. This function is called from blk_mq_submit_bio() after a BIO is split to avoid large BIOs spanning multiple zones which would cause mishandling of zone write plugs. This ichange enables by default zone write plugging for any mq request-based block device. BIO-based device drivers can also use zone write plugging by expliclty calling blk_zone_write_plug_bio() in their ->submit_bio method. For such devices, the driver must ensure that a BIO passed to blk_zone_write_plug_bio() is already split and not straddling zone boundaries. Only write and write zeroes BIOs are plugged. Zone write plugging does not introduce any significant overhead for other operations. A BIO that is being handled through zone write plugging is flagged using the new BIO flag BIO_ZONE_WRITE_PLUGGING. A request handling a BIO flagged with this new flag is flagged with the new RQF_ZONE_WRITE_PLUGGING flag. The completion of BIOs and requests flagged trigger respectively calls to the functions blk_zone_write_bio_endio() and blk_zone_write_complete_request(). The latter function is used to trigger submission of the next plugged BIO using the zone plug work. blk_zone_write_bio_endio() does the same for BIO-based devices. This ensures that at any time, at most one request (blk-mq devices) or one BIO (BIO-based devices) is being executed for any zone. The handling of zone write plugs using a per-zone plug spinlock maximizes parallelism and device usage by allowing multiple zones to be writen simultaneously without lock contention. Zone write plugging ignores flush BIOs without data. Hovever, any flush BIO that has data is always plugged so that the write part of the flush sequence is serialized with other regular writes. Given that any BIO handled through zone write plugging will be the only BIO in flight for the target zone when it is executed, the unplugging and submission of a BIO will have no chance of successfully merging with plugged requests or requests in the scheduler. To overcome this potential performance degradation, blk_mq_submit_bio() calls the function blk_zone_write_plug_attempt_merge() to try to merge other plugged BIOs with the one just unplugged and submitted. Successful merging is signaled using blk_zone_write_plug_bio_merged(), called from bio_attempt_back_merge(). Furthermore, to avoid recalculating the number of segments of plugged BIOs to attempt merging, the number of segments of a plugged BIO is saved using the new struct bio field __bi_nr_segments. To avoid growing the size of struct bio, this field is added as a union with the bio_cookie field. This is safe to do as polling is always disabled for plugged BIOs. When BIOs are plugged in a zone write plug, the device request queue usage counter is always incremented. This reference is kept and reused for blk-mq devices when the plugged BIO is unplugged and submitted again using submit_bio_noacct_nocheck(). For this case, the unplugged BIO is already flagged with BIO_ZONE_WRITE_PLUGGING and blk_mq_submit_bio() proceeds directly to allocating a new request for the BIO, re-using the usage reference count taken when the BIO was plugged. This extra reference count is dropped in blk_zone_write_plug_attempt_merge() for any plugged BIO that is successfully merged. Given that BIO-based devices will not take this path, the extra reference is dropped after a plugged BIO is unplugged and submitted. Zone write plugs are dynamically allocated and managed using a hash table (an array of struct hlist_head) with RCU protection. A zone write plug is allocated when a write BIO is received for the zone and not freed until the zone is fully written, reset or finished. To detect when a zone write plug can be freed, the write state of each zone is tracked using a write pointer offset which corresponds to the offset of a zone write pointer relative to the zone start. Write operations always increment this write pointer offset. Zone reset operations set it to 0 and zone finish operations set it to the zone size. If a write error happens, the wp_offset value of a zone write plug may become incorrect and out of sync with the device managed write pointer. This is handled using the zone write plug flag BLK_ZONE_WPLUG_ERROR. The function blk_zone_wplug_handle_error() is called from the new disk zone write plug work when this flag is set. This function executes a report zone to update the zone write pointer offset to the current value as indicated by the device. The disk zone write plug work is scheduled whenever a BIO flagged with BIO_ZONE_WRITE_PLUGGING completes with an error or when bio_zone_wplug_prepare_bio() detects an unaligned write. Once scheduled, the disk zone write plugs work keeps running until all zone errors are handled. To match the new data structures used for zoned disks, the function disk_free_zone_bitmaps() is renamed to the more generic disk_free_zone_resources(). The function disk_init_zone_resources() is also introduced to initialize zone write plugs resources when a gendisk is allocated. In order to guarantee that the user can simultaneously write up to a number of zones equal to a device max active zone limit or max open zone limit, zone write plugs are allocated using a mempool sized to the maximum of these 2 device limits. For a device that does not have active and open zone limits, 128 is used as the default mempool size. If a change to the device active and open zone limits is detected, the disk mempool is resized when blk_revalidate_disk_zones() is executed. This commit contains contributions from Christoph Hellwig <hch@lst.de>. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Tested-by: Dennis Maisenbacher <dennis.maisenbacher@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20240408014128.205141-8-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-17block: Remember zone capacity when revalidating zonesDamien Le Moal
In preparation for adding zone write plugging, modify blk_revalidate_disk_zones() to get the capacity of zones of a zoned block device. This capacity value as a number of 512B sectors is stored in the gendisk zone_capacity field. Given that host-managed SMR disks (including zoned UFS drives) and all known NVMe ZNS devices have the same zone capacity for all zones blk_revalidate_disk_zones() returns an error if different capacities are detected for different zones. This also adds check to verify that the values reported by the device for zone capacities are correct, that is, that the zone capacity is never 0, does not exceed the zone size and is equal to the zone size for conventional zones. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Tested-by: Dennis Maisenbacher <dennis.maisenbacher@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20240408014128.205141-7-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-17block: Introduce bio_straddles_zones() and bio_offset_from_zone_start()Damien Le Moal
Implement the inline helper functions bio_straddles_zones() and bio_offset_from_zone_start() to respectively test if a BIO crosses a zone boundary (the start sector and last sector belong to different zones) and to obtain the offset of a BIO from the start sector of its target zone. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Tested-by: Dennis Maisenbacher <dennis.maisenbacher@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20240408014128.205141-5-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-12scsi: block: Remove now unused queue limits helpersChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240409143748.980206-24-hch@lst.de Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: John Garry <john.g.garry@oracle.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2024-04-11scsi: block: Add a helper to cancel atomic queue limit updatesChristoph Hellwig
Drivers might have to perform complex actions to determine queue limits, and those might fail. Add a helper to cancel a queue limit update that can be called in those cases. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240409143748.980206-2-hch@lst.de Reviewed-by: Kanchan Joshi <joshi.k@samsung.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: John Garry <john.g.garry@oracle.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2024-04-08md: Fix overflow in is_mddev_idleLi Nan
UBSAN reports this problem: UBSAN: Undefined behaviour in drivers/md/md.c:8175:15 signed integer overflow: -2147483291 - 2072033152 cannot be represented in type 'int' Call trace: dump_backtrace+0x0/0x310 show_stack+0x28/0x38 dump_stack+0xec/0x15c ubsan_epilogue+0x18/0x84 handle_overflow+0x14c/0x19c __ubsan_handle_sub_overflow+0x34/0x44 is_mddev_idle+0x338/0x3d8 md_do_sync+0x1bb8/0x1cf8 md_thread+0x220/0x288 kthread+0x1d8/0x1e0 ret_from_fork+0x10/0x18 'curr_events' will overflow when stat accum or 'sync_io' is greater than INT_MAX. Fix it by changing sync_io, last_events and curr_events to 64bit. Signed-off-by: Li Nan <linan122@huawei.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20240117031946.2324519-2-linan666@huaweicloud.com Signed-off-by: Song Liu <song@kernel.org>
2024-03-27fs,block: yield devices earlyChristian Brauner
Currently a device is only really released once the umount returns to userspace due to how file closing works. That ultimately could cause an old umount assumption to be violated that concurrent umount and mount don't fail. So an exclusively held device with a temporary holder should be yielded before the filesystem is gone. Add a helper that allows callers to do that. This also allows us to remove the two holder ops that Linus wasn't excited about. Link: https://lore.kernel.org/r/20240326-vfs-bdev-end_holder-v1-1-20af85202918@kernel.org Fixes: f3a608827d1f ("bdev: open block device as files") # mainline only Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-03-18fs,block: get holder during claimChristian Brauner
Now that we open block devices as files we need to deal with the realities that closing is a deferred operation. An operation on the block device such as e.g., freeze, thaw, or removal that runs concurrently with umount, tries to acquire a stable reference on the holder. The holder might already be gone though. Make that reliable by grabbing a passive reference to the holder during bdev_open() and releasing it during bdev_release(). Fixes: f3a608827d1f ("bdev: open block device as files") # mainline only Reported-by: Christoph Hellwig <hch@infradead.org> Link: https://lore.kernel.org/r/ZfEQQ9jZZVes0WCZ@infradead.org Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@infradead.org> Tested-by: Yi Zhang <yi.zhang@redhat.com> Reported-by: https://lore.kernel.org/r/CAHj4cs8tbDwKRwfS1=DmooP73ysM__xAb2PQc6XsAmWR+VuYmg@mail.gmail.com Link: https://lore.kernel.org/r/20240315-freibad-annehmbar-ca68c375af91@brauner Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-03-11Merge tag 'for-6.9/block-20240310' of git://git.kernel.dk/linuxLinus Torvalds
Pull block updates from Jens Axboe: - MD pull requests via Song: - Cleanup redundant checks (Yu Kuai) - Remove deprecated headers (Marc Zyngier, Song Liu) - Concurrency fixes (Li Lingfeng) - Memory leak fix (Li Nan) - Refactor raid1 read_balance (Yu Kuai, Paul Luse) - Clean up and fix for md_ioctl (Li Nan) - Other small fixes (Gui-Dong Han, Heming Zhao) - MD atomic limits (Christoph) - NVMe pull request via Keith: - RDMA target enhancements (Max) - Fabrics fixes (Max, Guixin, Hannes) - Atomic queue_limits usage (Christoph) - Const use for class_register (Ricardo) - Identification error handling fixes (Shin'ichiro, Keith) - Improvement and cleanup for cached request handling (Christoph) - Moving towards atomic queue limits. Core changes and driver bits so far (Christoph) - Fix UAF issues in aoeblk (Chun-Yi) - Zoned fix and cleanups (Damien) - s390 dasd cleanups and fixes (Jan, Miroslav) - Block issue timestamp caching (me) - noio scope guarding for zoned IO (Johannes) - block/nvme PI improvements (Kanchan) - Ability to terminate long running discard loop (Keith) - bdev revalidation fix (Li) - Get rid of old nr_queues hack for kdump kernels (Ming) - Support for async deletion of ublk (Ming) - Improve IRQ bio recycling (Pavel) - Factor in CPU capacity for remote vs local completion (Qais) - Add shared_tags configfs entry for null_blk (Shin'ichiro - Fix for a regression in page refcounts introduced by the folio unification (Tony) - Misc fixes and cleanups (Arnd, Colin, John, Kunwu, Li, Navid, Ricardo, Roman, Tang, Uwe) * tag 'for-6.9/block-20240310' of git://git.kernel.dk/linux: (221 commits) block: partitions: only define function mac_fix_string for CONFIG_PPC_PMAC block/swim: Convert to platform remove callback returning void cdrom: gdrom: Convert to platform remove callback returning void block: remove disk_stack_limits md: remove mddev->queue md: don't initialize queue limits md/raid10: use the atomic queue limit update APIs md/raid5: use the atomic queue limit update APIs md/raid1: use the atomic queue limit update APIs md/raid0: use the atomic queue limit update APIs md: add queue limit helpers md: add a mddev_is_dm helper md: add a mddev_add_trace_msg helper md: add a mddev_trace_remap helper bcache: move calculation of stripe_size and io_opt into bcache_device_init virtio_blk: Do not use disk_set_max_open/active_zones() aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts block: move capacity validation to blkpg_do_ioctl() block: prevent division by zero in blk_rq_stat_sum() drbd: atomically update queue limits in drbd_reconsider_queue_parameters ...
2024-03-06Merge tag 'md-6.9-20240306' of ↵Jens Axboe
https://git.kernel.org/pub/scm/linux/kernel/git/song/md into for-6.9/block Pull MD atomic queue limits changes from Song. * tag 'md-6.9-20240306' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md: block: remove disk_stack_limits md: remove mddev->queue md: don't initialize queue limits md/raid10: use the atomic queue limit update APIs md/raid5: use the atomic queue limit update APIs md/raid1: use the atomic queue limit update APIs md/raid0: use the atomic queue limit update APIs md: add queue limit helpers md: add a mddev_is_dm helper md: add a mddev_add_trace_msg helper md: add a mddev_trace_remap helper
2024-03-06block: remove disk_stack_limitsChristoph Hellwig
disk_stack_limits is unused now, remove it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed--by: Song Liu <song@kernel.org> Tested-by: Song Liu <song@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240303140150.5435-12-hch@lst.de
2024-03-06block: make block_class constantRicardo B. Marliere
Since commit 43a7206b0963 ("driver core: class: make class_register() take a const *"), the driver core allows for struct class to be in read-only memory, so move the block_class structure to be declared at build time placing it into read-only memory, instead of having to be dynamically allocated at boot time. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240305-class_cleanup-block-v1-1-130bb27b9c72@marliere.net Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-01block: add a queue_limits_stack_bdev helperChristoph Hellwig
Add a small wrapper around blk_stack_limits that allows passing a bdev for the bottom device and prints an error in case of misaligned device. The name fits into the new queue limits API and the intent is to eventually replace disk_stack_limits. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240228225653.947152-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-01block: add a queue_limits_set helperChristoph Hellwig
Add a small wrapper around queue_limits_commit_update for stacking drivers that don't want to update existing limits, but set an entirely new set. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240228225653.947152-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-25bdev: make struct bdev_handle private to the block layerChristian Brauner
Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-29-adbd023e19cc@kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-25bdev: make bdev_{release, open_by_dev}() private to block layerChristian Brauner
Move both of them to the private block header. There's no caller in the tree anymore that uses them directly. Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-28-adbd023e19cc@kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-25bdev: remove bdev_open_by_path()Christian Brauner
Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-27-adbd023e19cc@kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-25bdev: open block device as filesChristian Brauner
Add two new helpers to allow opening block devices as files. This is not the final infrastructure. This still opens the block device before opening a struct a file. Until we have removed all references to struct bdev_handle we can't switch the order: * Introduce blk_to_file_flags() to translate from block specific to flags usable to pen a new file. * Introduce bdev_file_open_by_{dev,path}(). * Introduce temporary sb_bdev_handle() helper to retrieve a struct bdev_handle from a block device file and update places that directly reference struct bdev_handle to rely on it. * Don't count block device openes against the number of open files. A bdev_file_open_by_{dev,path}() file is never installed into any file descriptor table. One idea that came to mind was to use kernel_tmpfile_open() which would require us to pass a path and it would then call do_dentry_open() going through the regular fops->open::blkdev_open() path. But then we're back to the problem of routing block specific flags such as BLK_OPEN_RESTRICT_WRITES through the open path and would have to waste FMODE_* flags every time we add a new one. With this we can avoid using a flag bit and we have more leeway in how we open block devices from bdev_open_by_{dev,path}(). Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-1-adbd023e19cc@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-19block: pass a queue_limits argument to blk_alloc_diskChristoph Hellwig
Pass a queue_limits to blk_alloc_disk and apply it if non-NULL. This will allow allocating queues with valid queue limits instead of setting the values one at a time later. Also change blk_alloc_disk to return an ERR_PTR instead of just NULL which can't distinguish errors. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Link: https://lore.kernel.org/r/20240215071055.2201424-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-13block: add a max_user_discard_sectors queue limitChristoph Hellwig
Add a new max_user_discard_sectors limit that mirrors max_user_sectors and stores the value that the user manually set. This now allows updates of the max_hw_discard_sectors to not worry about the user limit. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20240213073425.1621680-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-13block: add an API to atomically update queue limitsChristoph Hellwig
Add a new queue_limits_{start,commit}_update pair of functions that allows taking an atomic snapshot of queue limits, update it, and commit it if it passes validity checking. Also use the low-level validation helper to implement blk_set_default_limits instead of duplicating the initialization. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20240213073425.1621680-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-13block: move max_{open,active}_zones to struct queue_limitsChristoph Hellwig
The maximum number of open and active zones is a limit on the queue and should be places there so that we can including it in the upcoming queue limits batch update API. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20240213073425.1621680-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-12block: support PI at non-zero offset within metadataKanchan Joshi
Block layer integrity processing assumes that protection information (PI) is placed in the first bytes of each metadata block. Remove this limitation and include the metadata before the PI in the calculation of the guard tag. Signed-off-by: Kanchan Joshi <joshi.k@samsung.com> Signed-off-by: Chinmay Gameti <c.gameti@samsung.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20240201130126.211402-3-joshi.k@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-12block: remove gfp_flags from blkdev_zone_mgmtJohannes Thumshirn
Now that all callers pass in GFP_KERNEL to blkdev_zone_mgmt() and use memalloc_no{io,fs}_{save,restore}() to define the allocation scope, we can drop the gfp_mask parameter from blkdev_zone_mgmt() as well as blkdev_zone_reset_all() and blkdev_zone_reset_all_emulated(). Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Mike Snitzer <snitzer@kernel.org> Link: https://lore.kernel.org/r/20240128-zonefs_nofs-v3-5-ae3b7c8def61@wdc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-05block: update cached timestamp post schedule/preemptionJens Axboe
Mark the task as having a cached timestamp when set assign it, so we can efficiently check if it needs updating post being scheduled back in. This covers both the actual schedule out case, which would've flushed the plug, and the preemption case which doesn't touch the plugged requests (for many reasons, one of them being then we'd need to have preemption disabled around plug state manipulation). Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-05block: cache current nsec time in struct blk_plugJens Axboe
Querying the current time is the most costly thing we do in the block layer per IO, and depending on kernel config settings, we may do it many times per IO. None of the callers actually need nsec granularity. Take advantage of that by caching the current time in the plug, with the assumption here being that any time checking will be temporally close enough that the slight loss of precision doesn't matter. If the block plug gets flushed, eg on preempt or schedule out, then we invalidate the cached clock. On a basic peak IOPS test case with iostats enabled, this changes the performance from: IOPS=108.41M, BW=52.93GiB/s, IOS/call=31/31 IOPS=108.43M, BW=52.94GiB/s, IOS/call=32/32 IOPS=108.29M, BW=52.88GiB/s, IOS/call=31/32 IOPS=108.35M, BW=52.91GiB/s, IOS/call=32/32 IOPS=108.42M, BW=52.94GiB/s, IOS/call=31/31 IOPS=108.40M, BW=52.93GiB/s, IOS/call=32/32 IOPS=108.31M, BW=52.89GiB/s, IOS/call=32/31 to IOPS=118.79M, BW=58.00GiB/s, IOS/call=31/32 IOPS=118.62M, BW=57.92GiB/s, IOS/call=31/31 IOPS=118.80M, BW=58.01GiB/s, IOS/call=32/31 IOPS=118.78M, BW=58.00GiB/s, IOS/call=32/32 IOPS=118.69M, BW=57.95GiB/s, IOS/call=32/31 IOPS=118.62M, BW=57.92GiB/s, IOS/call=32/31 IOPS=118.63M, BW=57.92GiB/s, IOS/call=31/32 which is more than a 9% improvement in performance. Looking at perf diff, we can see a huge reduction in time overhead: 10.55% -9.88% [kernel.vmlinux] [k] read_tsc 1.31% -1.22% [kernel.vmlinux] [k] ktime_get Note that since this relies on blk_plug for the caching, it's only applicable to the issue side. But this is where most of the time calls happen anyway. On the completion side, cached time stamping is done with struct io_comp patch, as long as the driver supports it. It's also worth noting that the above testing doesn't enable any of the higher cost CPU items on the block layer side, like wbt, cgroups, iocost, etc, which all would add additional time querying and hence overhead. IOW, results would likely look even better in comparison with those enabled, as distros would do. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-01-11Merge tag 'for-6.8/block-2024-01-08' of git://git.kernel.dk/linuxLinus Torvalds
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 ...
2024-01-08Merge tag 'vfs-6.8.super' of ↵Linus Torvalds
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 ...