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2025-03-26Merge tag 'for-6.15/block-20250322' of git://git.kernel.dk/linuxLinus Torvalds
Pull block updates from Jens Axboe: - Fixes for integrity handling - NVMe pull request via Keith: - Secure concatenation for TCP transport (Hannes) - Multipath sysfs visibility (Nilay) - Various cleanups (Qasim, Baruch, Wang, Chen, Mike, Damien, Li) - Correct use of 64-bit BARs for pci-epf target (Niklas) - Socket fix for selinux when used in containers (Peijie) - MD pull request via Yu: - fix recovery can preempt resync (Li Nan) - fix md-bitmap IO limit (Su Yue) - fix raid10 discard with REQ_NOWAIT (Xiao Ni) - fix raid1 memory leak (Zheng Qixing) - fix mddev uaf (Yu Kuai) - fix raid1,raid10 IO flags (Yu Kuai) - some refactor and cleanup (Yu Kuai) - Series cleaning up and fixing bugs in the bad block handling code - Improve support for write failure simulation in null_blk - Various lock ordering fixes - Fixes for locking for debugfs attributes - Various ublk related fixes and improvements - Cleanups for blk-rq-qos wait handling - blk-throttle fixes - Fixes for loop dio and sync handling - Fixes and cleanups for the auto-PI code - Block side support for hardware encryption keys in blk-crypto - Various cleanups and fixes * tag 'for-6.15/block-20250322' of git://git.kernel.dk/linux: (105 commits) nvmet: replace max(a, min(b, c)) by clamp(val, lo, hi) nvme-tcp: fix selinux denied when calling sock_sendmsg nvmet: pci-epf: Always configure BAR0 as 64-bit nvmet: Remove duplicate uuid_copy nvme: zns: Simplify nvme_zone_parse_entry() nvmet: pci-epf: Remove redundant 'flush_workqueue()' calls nvmet-fc: Remove unused functions nvme-pci: remove stale comment nvme-fc: Utilise min3() to simplify queue count calculation nvme-multipath: Add visibility for queue-depth io-policy nvme-multipath: Add visibility for numa io-policy nvme-multipath: Add visibility for round-robin io-policy nvmet: add tls_concat and tls_key debugfs entries nvmet-tcp: support secure channel concatenation nvmet: Add 'sq' argument to alloc_ctrl_args nvme-fabrics: reset admin connection for secure concatenation nvme-tcp: request secure channel concatenation nvme-keyring: add nvme_tls_psk_refresh() nvme: add nvme_auth_derive_tls_psk() nvme: add nvme_auth_generate_digest() ...
2025-03-13block: remove unused parameter 'q' parameter in __blk_rq_map_sg()Anuj Gupta
request_queue param is no longer used by blk_rq_map_sg and __blk_rq_map_sg. Remove it. Signed-off-by: Anuj Gupta <anuj20.g@samsung.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20250313035322.243239-1-anuj20.g@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-25block: make segment size limit workable for > 4K PAGE_SIZEMing Lei
Using PAGE_SIZE as a minimum expected DMA segment size in consideration of devices which have a max DMA segment size of < 64k when used on 64k PAGE_SIZE systems leads to devices not being able to probe such as eMMC and Exynos UFS controller [0] [1] you can end up with a probe failure as follows: WARNING: CPU: 2 PID: 397 at block/blk-settings.c:339 blk_validate_limits+0x364/0x3c0 Ensure we use min(max_seg_size, seg_boundary_mask + 1) as the new min segment size when max segment size is < PAGE_SIZE for 16k and 64k base page size systems. If anyone need to backport this patch, the following commits are depended: commit 6aeb4f836480 ("block: remove bio_add_pc_page") commit 02ee5d69e3ba ("block: remove blk_rq_bio_prep") commit b7175e24d6ac ("block: add a dma mapping iterator") Link: https://lore.kernel.org/linux-block/20230612203314.17820-1-bvanassche@acm.org/ # [0] Link: https://lore.kernel.org/linux-block/1d55e942-5150-de4c-3a02-c3d066f87028@acm.org/ # [1] Cc: Yi Zhang <yi.zhang@redhat.com> Cc: John Garry <john.g.garry@oracle.com> Cc: Keith Busch <kbusch@kernel.org> Tested-by: Paul Bunyan <pbunyan@redhat.com> Reviewed-by: Daniel Gomez <da.gomez@kernel.org> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20250225022141.2154581-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-17block: fix NULL pointer dereferenced within __blk_rq_map_sgMing Lei
The block layer internal flush request may not have bio attached, so the request iterator has to be initialized from valid req->bio, otherwise NULL pointer dereferenced is triggered. Cc: Christoph Hellwig <hch@lst.de> Reported-and-tested-by: Cheyenne Wills <cheyenne.wills@gmail.com> Fixes: b7175e24d6ac ("block: add a dma mapping iterator") Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20250217031626.461977-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-14block/merge: remove unnecessary min() with UINT_MAXCaleb Sander Mateos
In bvec_split_segs(), max_bytes is an unsigned, so it must be less than or equal to UINT_MAX. Remove the unnecessary min(). Prior to commit 67927d220150 ("block/merge: count bytes instead of sectors"), the min() was with UINT_MAX >> 9, so it did have an effect. Signed-off-by: Caleb Sander Mateos <csander@purestorage.com> Link: https://lore.kernel.org/r/20250214193637.234702-1-csander@purestorage.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-01-06block: add a dma mapping iteratorChristoph Hellwig
blk_rq_map_sg is maze of nested loops. Untangle it by creating an iterator that returns [paddr,len] tuples for DMA mapping, and then implement the DMA logic on top of this. This not only removes code at the source level, but also generates nicer binary code: $ size block/blk-merge.o.* text data bss dec hex filename 10001 432 0 10433 28c1 block/blk-merge.o.new 10317 468 0 10785 2a21 block/blk-merge.o.old Last but not least it will be used as a building block for a new DMA mapping helper that doesn't rely on struct scatterlist. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20250106081609.798289-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-19block: req->bio is always set in the merge codeChristoph Hellwig
As smatch, which is a lot smarter than me noticed. So remove the checks for it, and condense these checks a bit including the comments stating the obvious. Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: John Garry <john.g.garry@oracle.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20241119161157.1328171-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-19block: don't bother checking the data direction for mergesChristoph Hellwig
Because it already is encoded in the opcode. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: John Garry <john.g.garry@oracle.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20241119161157.1328171-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-13block: add a rq_list typeChristoph Hellwig
Replace the semi-open coded request list helpers with a proper rq_list type that mirrors the bio_list and has head and tail pointers. Besides better type safety this actually allows to insert at the tail of the list, which will be useful soon. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20241113152050.157179-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-12block: remove the ioprio field from struct requestChristoph Hellwig
The request ioprio is only initialized from the first attached bio, so requests without a bio already never set it. Directly use the bio field instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20241112170050.1612998-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-12block: remove the write_hint field from struct requestChristoph Hellwig
The write_hint is only used for read/write requests, which must have a bio attached to them. Just use the bio field instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20241112170050.1612998-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-11block: pre-calculate max_zone_append_sectorsChristoph Hellwig
max_zone_append_sectors differs from all other queue limits in that the final value used is not stored in the queue_limits but needs to be obtained using queue_limits_max_zone_append_sectors helper. This not only adds (tiny) extra overhead to the I/O path, but also can be easily forgotten in file system code. Add a new max_hw_zone_append_sectors value to queue_limits which is set by the driver, and calculate max_zone_append_sectors from that and the other inputs in blk_validate_zoned_limits, similar to how max_sectors is calculated to fix this. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20241104073955.112324-3-hch@lst.de Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20241108154657.845768-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-11block: fix bio_split_rw_at to take zone_write_granularity into accountChristoph Hellwig
Otherwise it can create unaligned writes on zoned devices. Fixes: a805a4fa4fa3 ("block: introduce zone_write_granularity limit") Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20241104062647.91160-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-11block: take chunk_sectors into account in bio_split_write_zeroesChristoph Hellwig
For zoned devices, write zeroes must be split at the zone boundary which is represented as chunk_sectors. For other uses like the internally RAIDed NVMe devices it is probably at least useful. Enhance get_max_io_size to know about write zeroes and use it in bio_split_write_zeroes. Also add a comment about the seemingly nonsensical zero max_write_zeroes limit. Fixes: 885fa13f6559 ("block: implement splitting of REQ_OP_WRITE_ZEROES bios") Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20241104062647.91160-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-11block: Handle bio_split() errors in bio_submit_split()John Garry
bio_split() may error, so check this. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: John Garry <john.g.garry@oracle.com> Link: https://lore.kernel.org/r/20241111112150.3756529-4-john.g.garry@oracle.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-07Revert "block: pre-calculate max_zone_append_sectors"Jens Axboe
This causes issue on, at least, nvme-mpath where my boot fails with: WARNING: CPU: 354 PID: 2729 at block/blk-settings.c:75 blk_validate_limits+0x356/0x380 Modules linked in: tg3(+) nvme usbcore scsi_mod ptp i2c_piix4 libphy nvme_core crc32c_intel scsi_common usb_common pps_core i2c_smbus CPU: 354 UID: 0 PID: 2729 Comm: kworker/u2061:1 Not tainted 6.12.0-rc6+ #181 Hardware name: Dell Inc. PowerEdge R7625/06444F, BIOS 1.8.3 04/02/2024 Workqueue: async async_run_entry_fn RIP: 0010:blk_validate_limits+0x356/0x380 Code: f6 47 01 04 75 28 83 bf 94 00 00 00 00 75 39 83 bf 98 00 00 00 00 75 34 83 7f 68 00 75 32 31 c0 83 7f 5c 00 0f 84 9b fd ff ff <0f> 0b eb 13 0f 0b eb 0f 48 c7 c0 74 12 58 92 48 89 c7 e8 13 76 46 RSP: 0018:ffffa8a1dfb93b30 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff9232829c8388 RCX: 0000000000000088 RDX: 0000000000000080 RSI: 0000000000000200 RDI: ffffa8a1dfb93c38 RBP: 000000000000000c R08: 00000000ffffffff R09: 000000000000ffff R10: 0000000000000000 R11: 0000000000000000 R12: ffff9232829b9000 R13: ffff9232829b9010 R14: ffffa8a1dfb93c38 R15: ffffa8a1dfb93c38 FS: 0000000000000000(0000) GS:ffff923867c80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c1b92480a8 CR3: 0000002484ff0002 CR4: 0000000000370ef0 Call Trace: <TASK> ? __warn+0xca/0x1a0 ? blk_validate_limits+0x356/0x380 ? report_bug+0x11a/0x1a0 ? handle_bug+0x5e/0x90 ? exc_invalid_op+0x16/0x40 ? asm_exc_invalid_op+0x16/0x20 ? blk_validate_limits+0x356/0x380 blk_alloc_queue+0x7a/0x250 __blk_alloc_disk+0x39/0x80 nvme_mpath_alloc_disk+0x13d/0x1b0 [nvme_core] nvme_scan_ns+0xcc7/0x1010 [nvme_core] async_run_entry_fn+0x27/0x120 process_scheduled_works+0x1a0/0x360 worker_thread+0x2bc/0x350 ? pr_cont_work+0x1b0/0x1b0 kthread+0x111/0x120 ? kthread_unuse_mm+0x90/0x90 ret_from_fork+0x30/0x40 ? kthread_unuse_mm+0x90/0x90 ret_from_fork_asm+0x11/0x20 </TASK> ---[ end trace 0000000000000000 ]--- presumably due to max_zone_append_sectors not being cleared to zero, resulting in blk_validate_zoned_limits() complaining and failing. This reverts commit 2a8f6153e1c2db06a537a5c9d61102eb591776f1. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-11-04block: pre-calculate max_zone_append_sectorsChristoph Hellwig
max_zone_append_sectors differs from all other queue limits in that the final value used is not stored in the queue_limits but needs to be obtained using queue_limits_max_zone_append_sectors helper. This not only adds (tiny) extra overhead to the I/O path, but also can be easily forgotten in file system code. Add a new max_hw_zone_append_sectors value to queue_limits which is set by the driver, and calculate max_zone_append_sectors from that and the other inputs in blk_validate_zoned_limits, similar to how max_sectors is calculated to fix this. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20241104073955.112324-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-29block: add a bdev_limits helperChristoph Hellwig
Add a helper to get the queue_limits from the bdev without having to poke into the request_queue. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: John Garry <john.g.garry@oracle.com> Link: https://lore.kernel.org/r/20241029141937.249920-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-10-22block: kill blk_do_io_stat() helperJens Axboe
It's now just checking whether or not RQF_IO_STAT is set, so let's get rid of it and just open-code the specific flag that is being checked. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-09-13blk-integrity: properly account for segmentsKeith Busch
Both types of merging when integrity data is used are miscounting the segments: Merging two requests wasn't accounting for the new segment count, so add the "next" segment count to the first on a successful merge to ensure this value is accurate. Merging a bio into an existing request was double counting the bio's segments, even if the merge failed later on. Move the segment accounting to the end when the merge is successful. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20240913182854.2445457-4-kbusch@meta.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-08-29block: properly handle REQ_OP_ZONE_APPEND in __bio_split_to_limitsChristoph Hellwig
Currently REQ_OP_ZONE_APPEND is handled by the bio_split_rw case in __bio_split_to_limits. This is harmful because REQ_OP_ZONE_APPEND bios do not adhere to the soft max_limits value but instead use their own capped version of max_hw_sectors, leading to incorrect splits that later blow up in bio_split. We still need the bio_split_rw logic to count nr_segs for blk-mq code, so add a new wrapper that passes in the right limit, and turns any bio that would need a split into an error as an additional debugging aid. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com> Link: https://lore.kernel.org/r/20240826173820.1690925-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-08-29block: rework bio splittingChristoph Hellwig
The current setup with bio_may_exceed_limit and __bio_split_to_limits is a bit of a mess. Change it so that __bio_split_to_limits does all the work and is just a variant of bio_split_to_limits that returns nr_segs. This is done by inlining it and instead have the various bio_split_* helpers directly submit the potentially split bios. To support btrfs, the rw version has a lower level helper split out that just returns the offset to split. This turns out to nicely clean up the btrfs flow as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: David Sterba <dsterba@suse.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Tested-by: Hans Holmberg <hans.holmberg@wdc.com> Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com> Link: https://lore.kernel.org/r/20240826173820.1690925-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-07-09block: take offset into account in blk_bvec_map_sg againChristoph Hellwig
The rebase of commit 09595e0c9d65 ("block: pass a phys_addr_t to get_max_segment_size") lost adding the total to to the offset in blk_bvec_map_sg. Add it back. Fixes: 09595e0c9d65 ("block: pass a phys_addr_t to get_max_segment_size") Reported-by: Yi Zhang <yi.zhang@redhat.com> Reported-by: Chaitanya Kulkarni <chaitanyak@nvidia.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240709070126.3019940-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-07-09block: fix get_max_segment_size() warningChaitanya Kulkarni
Correct the parameter name in the comment of get_max_segment_size() to fix following warning:- block/blk-merge.c:220: warning: Function parameter or struct member 'len' not described in 'get_max_segment_size' block/blk-merge.c:220: warning: Excess function parameter 'max_len' description in 'get_max_segment_size' Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20240709045432.8688-1-kch@nvidia.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-07-08block: pass a phys_addr_t to get_max_segment_sizeChristoph Hellwig
Work on a single address to simplify the logic, and prepare the callers from using better helpers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20240706075228.2350978-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-06-20block: Add core atomic write supportJohn Garry
Add atomic write support, as follows: - add helper functions to get request_queue atomic write limits - report request_queue atomic write support limits to sysfs and update Doc - support to safely merge atomic writes - deal with splitting atomic writes - misc helper functions - add a per-request atomic write flag New request_queue limits are added, as follows: - atomic_write_hw_max is set by the block driver and is the maximum length of an atomic write which the device may support. It is not necessarily a power-of-2. - atomic_write_max_sectors is derived from atomic_write_hw_max_sectors and max_hw_sectors. It is always a power-of-2. Atomic writes may be merged, and atomic_write_max_sectors would be the limit on a merged atomic write request size. This value is not capped at max_sectors, as the value in max_sectors can be controlled from userspace, and it would only cause trouble if userspace could limit atomic_write_unit_max_bytes and the other atomic write limits. - atomic_write_hw_unit_{min,max} are set by the block driver and are the min/max length of an atomic write unit which the device may support. They both must be a power-of-2. Typically atomic_write_hw_unit_max will hold the same value as atomic_write_hw_max. - atomic_write_unit_{min,max} are derived from atomic_write_hw_unit_{min,max}, max_hw_sectors, and block core limits. Both min and max values must be a power-of-2. - atomic_write_hw_boundary is set by the block driver. If non-zero, it indicates an LBA space boundary at which an atomic write straddles no longer is atomically executed by the disk. The value must be a power-of-2. Note that it would be acceptable to enforce a rule that atomic_write_hw_boundary_sectors is a multiple of atomic_write_hw_unit_max, but the resultant code would be more complicated. All atomic writes limits are by default set 0 to indicate no atomic write support. Even though it is assumed by Linux that a logical block can always be atomically written, we ignore this as it is not of particular interest. Stacked devices are just not supported either for now. An atomic write must always be submitted to the block driver as part of a single request. As such, only a single BIO must be submitted to the block layer for an atomic write. When a single atomic write BIO is submitted, it cannot be split. As such, atomic_write_unit_{max, min}_bytes are limited by the maximum guaranteed BIO size which will not be required to be split. This max size is calculated by request_queue max segments and the number of bvecs a BIO can fit, BIO_MAX_VECS. Currently we rely on userspace issuing a write with iovcnt=1 for pwritev2() - as such, we can rely on each segment containing PAGE_SIZE of data, apart from the first+last, which each can fit logical block size of data. The first+last will be LBS length/aligned as we rely on direct IO alignment rules also. New sysfs files are added to report the following atomic write limits: - atomic_write_unit_max_bytes - same as atomic_write_unit_max_sectors in bytes - atomic_write_unit_min_bytes - same as atomic_write_unit_min_sectors in bytes - atomic_write_boundary_bytes - same as atomic_write_hw_boundary_sectors in bytes - atomic_write_max_bytes - same as atomic_write_max_sectors in bytes Atomic writes may only be merged with other atomic writes and only under the following conditions: - total resultant request length <= atomic_write_max_bytes - the merged write does not straddle a boundary Helper function bdev_can_atomic_write() is added to indicate whether atomic writes may be issued to a bdev. If a bdev is a partition, the partition start must be aligned with both atomic_write_unit_min_sectors and atomic_write_hw_boundary_sectors. FSes will rely on the block layer to validate that an atomic write BIO submitted will be of valid size, so add blk_validate_atomic_write_op_size() for this purpose. Userspace expects an atomic write which is of invalid size to be rejected with -EINVAL, so add BLK_STS_INVAL for this. Also use BLK_STS_INVAL for when a BIO needs to be split, as this should mean an invalid size BIO. Flag REQ_ATOMIC is used for indicating an atomic write. Co-developed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Signed-off-by: Himanshu Madhani <himanshu.madhani@oracle.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: John Garry <john.g.garry@oracle.com> Reviewed-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20240620125359.2684798-6-john.g.garry@oracle.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-06-20block: Generalize chunk_sectors support as boundary supportJohn Garry
The purpose of the chunk_sectors limit is to ensure that a mergeble request fits within the boundary of the chunck_sector value. Such a feature will be useful for other request_queue boundary limits, so generalize the chunk_sectors merge code. This idea was proposed by Hannes Reinecke. Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: John Garry <john.g.garry@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Link: https://lore.kernel.org/r/20240620125359.2684798-3-john.g.garry@oracle.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-06-20block: Pass blk_queue_get_max_sectors() a request pointerJohn Garry
Currently blk_queue_get_max_sectors() is passed a enum req_op. In future the value returned from blk_queue_get_max_sectors() may depend on certain request flags, so pass a request pointer. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: John Garry <john.g.garry@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Link: https://lore.kernel.org/r/20240620125359.2684798-2-john.g.garry@oracle.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-05-09block: support to account io_ticks preciselyYu Kuai
Currently, io_ticks is accounted based on sampling, specifically update_io_ticks() will always account io_ticks by 1 jiffies from bdev_start_io_acct()/blk_account_io_start(), and the result can be inaccurate, for example(HZ is 250): Test script: fio -filename=/dev/sda -bs=4k -rw=write -direct=1 -name=test -thinktime=4ms Test result: util is about 90%, while the disk is really idle. This behaviour is introduced by commit 5b18b5a73760 ("block: delete part_round_stats and switch to less precise counting"), however, there was a key point that is missed that this patch also improve performance a lot: Before the commit: part_round_stats: if (part->stamp != now) stats |= 1; part_in_flight() -> there can be lots of task here in 1 jiffies. part_round_stats_single() __part_stat_add() part->stamp = now; After the commit: update_io_ticks: stamp = part->bd_stamp; if (time_after(now, stamp)) if (try_cmpxchg()) __part_stat_add() -> only one task can reach here in 1 jiffies. Hence in order to account io_ticks precisely, we only need to know if there are IO inflight at most once in one jiffies. Noted that for rq-based device, iterating tags should not be used here because 'tags->lock' is grabbed in blk_mq_find_and_get_req(), hence part_stat_lock_inc/dec() and part_in_flight() is used to trace inflight. The additional overhead is quite little: - per cpu add/dec for each IO for rq-based device; - per cpu sum for each jiffies; And it's verified by null-blk that there are no performance degration under heavy IO pressure. Fixes: 5b18b5a73760 ("block: delete part_round_stats and switch to less precise counting") Signed-off-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20240509123717.3223892-2-yukuai1@huaweicloud.com 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: 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: Allow using bio_attempt_back_merge() internallyDamien Le Moal
Remove "static" from the definition of bio_attempt_back_merge() and declare this function in block/blk.h to allow using it internally from other block layer files. The definition of enum bio_merge_status is also moved to block/blk.h. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Christoph Hellwig <hch@lst.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: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20240408014128.205141-6-dlemoal@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-26block: Make blk_rq_set_mixed_merge() staticJohn Garry
Since commit 8e756373d7c8 ("block: Move bio merge related functions into blk-merge.c"), blk_rq_set_mixed_merge() has only been referenced in blk-merge.c, so make it static. Signed-off-by: John Garry <john.g.garry@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240325083501.2816408-1-john.g.garry@oracle.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-06block, fs: Restore the per-bio/request data lifetime fieldsBart Van Assche
Restore support for passing data lifetime information from filesystems to block drivers. This patch reverts commit b179c98f7697 ("block: Remove request.write_hint") and commit c75e707fe1aa ("block: remove the per-bio/request write hint"). This patch does not modify the size of struct bio because the new bi_write_hint member fills a hole in struct bio. pahole reports the following for struct bio on an x86_64 system with this patch applied: /* size: 112, cachelines: 2, members: 20 */ /* sum members: 110, holes: 1, sum holes: 2 */ /* last cacheline: 48 bytes */ Reviewed-by: Kanchan Joshi <joshi.k@samsung.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20240202203926.2478590-7-bvanassche@acm.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-12-29block: remove two comments in bio_split_discardChristoph Hellwig
A zero discard_granularity is not treated the same as a single-block one, and not having any segments after taking alignment is perfectly fine and does not need a warning. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20231228075545.362768-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-03-16blk-mq: release crypto keyslot before reporting I/O completeEric Biggers
Once all I/O using a blk_crypto_key has completed, filesystems can call blk_crypto_evict_key(). However, the block layer currently doesn't call blk_crypto_put_keyslot() until the request is being freed, which happens after upper layers have been told (via bio_endio()) the I/O has completed. This causes a race condition where blk_crypto_evict_key() can see 'slot_refs != 0' without there being an actual bug. This makes __blk_crypto_evict_key() hit the 'WARN_ON_ONCE(atomic_read(&slot->slot_refs) != 0)' and return without doing anything, eventually causing a use-after-free in blk_crypto_reprogram_all_keys(). (This is a very rare bug and has only been seen when per-file keys are being used with fscrypt.) There are two options to fix this: either release the keyslot before bio_endio() is called on the request's last bio, or make __blk_crypto_evict_key() ignore slot_refs. Let's go with the first solution, since it preserves the ability to report bugs (via WARN_ON_ONCE) where a key is evicted while still in-use. Fixes: a892c8d52c02 ("block: Inline encryption support for blk-mq") Cc: stable@vger.kernel.org Reviewed-by: Nathan Huckleberry <nhuck@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20230315183907.53675-2-ebiggers@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-03-03Merge tag 'block-6.3-2023-03-03' of git://git.kernel.dk/linuxLinus Torvalds
Pull block fixes from Jens Axboe: - NVMe pull request via Christoph: - Don't access released socket during error recovery (Akinobu Mita) - Bring back auto-removal of deleted namespaces during sequential scan (Christoph Hellwig) - Fix an error code in nvme_auth_process_dhchap_challenge (Dan Carpenter) - Show well known discovery name (Daniel Wagner) - Add a missing endianess conversion in effects masking (Keith Busch) - Fix for a regression introduced in blk-rq-qos during init in this merge window (Breno) - Reorder a few fields in struct blk_mq_tag_set, eliminating a few holes and shrinking it (Christophe) - Remove redundant bdev_get_queue() NULL checks (Juhyung) - Add sed-opal single user mode support flag (Luca) - Remove SQE128 check in ublk as it isn't needed, saving some memory (Ming) - Op specific segment checking for cloned requests (Uday) - Exclusive open partition scan fixes (Yu) - Loop offset/size checking before assigning them in the device (Zhong) - Bio polling fixes (me) * tag 'block-6.3-2023-03-03' of git://git.kernel.dk/linux: blk-mq: enforce op-specific segment limits in blk_insert_cloned_request nvme-fabrics: show well known discovery name nvme-tcp: don't access released socket during error recovery nvme-auth: fix an error code in nvme_auth_process_dhchap_challenge() nvme: bring back auto-removal of deleted namespaces during sequential scan blk-iocost: Pass gendisk to ioc_refresh_params nvme: fix sparse warning on effects masking block: be a bit more careful in checking for NULL bdev while polling block: clear bio->bi_bdev when putting a bio back in the cache loop: loop_set_status_from_info() check before assignment ublk: remove check IO_URING_F_SQE128 in ublk_ch_uring_cmd block: remove more NULL checks after bdev_get_queue() blk-mq: Reorder fields in 'struct blk_mq_tag_set' block: fix scan partition for exclusively open device again block: Revert "block: Do not reread partition table on exclusively open device" sed-opal: add support flag for SUM in status ioctl
2023-03-02blk-mq: enforce op-specific segment limits in blk_insert_cloned_requestUday Shankar
The block layer might merge together discard requests up until the max_discard_segments limit is hit, but blk_insert_cloned_request checks the segment count against max_segments regardless of the req op. This can result in errors like the following when discards are issued through a DM device and max_discard_segments exceeds max_segments for the queue of the chosen underlying device. blk_insert_cloned_request: over max segments limit. (256 > 129) Fix this by looking at the req_op and enforcing the appropriate segment limit - max_discard_segments for REQ_OP_DISCARDs and max_segments for everything else. Signed-off-by: Uday Shankar <ushankar@purestorage.com> Reviewed-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20230301000655.48112-1-ushankar@purestorage.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-20Merge tag 'for-6.3/block-2023-02-16' of git://git.kernel.dk/linuxLinus Torvalds
Pull block updates from Jens Axboe: - NVMe updates via Christoph: - Small improvements to the logging functionality (Amit Engel) - Authentication cleanups (Hannes Reinecke) - Cleanup and optimize the DMA mapping cod in the PCIe driver (Keith Busch) - Work around the command effects for Format NVM (Keith Busch) - Misc cleanups (Keith Busch, Christoph Hellwig) - Fix and cleanup freeing single sgl (Keith Busch) - MD updates via Song: - Fix a rare crash during the takeover process - Don't update recovery_cp when curr_resync is ACTIVE - Free writes_pending in md_stop - Change active_io to percpu - Updates to drbd, inching us closer to unifying the out-of-tree driver with the in-tree one (Andreas, Christoph, Lars, Robert) - BFQ update adding support for multi-actuator drives (Paolo, Federico, Davide) - Make brd compliant with REQ_NOWAIT (me) - Fix for IOPOLL and queue entering, fixing stalled IO waiting on timeouts (me) - Fix for REQ_NOWAIT with multiple bios (me) - Fix memory leak in blktrace cleanup (Greg) - Clean up sbitmap and fix a potential hang (Kemeng) - Clean up some bits in BFQ, and fix a bug in the request injection (Kemeng) - Clean up the request allocation and issue code, and fix some bugs related to that (Kemeng) - ublk updates and fixes: - Add support for unprivileged ublk (Ming) - Improve device deletion handling (Ming) - Misc (Liu, Ziyang) - s390 dasd fixes (Alexander, Qiheng) - Improve utility of request caching and fixes (Anuj, Xiao) - zoned cleanups (Pankaj) - More constification for kobjs (Thomas) - blk-iocost cleanups (Yu) - Remove bio splitting from drivers that don't need it (Christoph) - Switch blk-cgroups to use struct gendisk. Some of this is now incomplete as select late reverts were done. (Christoph) - Add bvec initialization helpers, and convert callers to use that rather than open-coding it (Christoph) - Misc fixes and cleanups (Jinke, Keith, Arnd, Bart, Li, Martin, Matthew, Ulf, Zhong) * tag 'for-6.3/block-2023-02-16' of git://git.kernel.dk/linux: (169 commits) brd: use radix_tree_maybe_preload instead of radix_tree_preload block: use proper return value from bio_failfast() block: bio-integrity: Copy flags when bio_integrity_payload is cloned block: Fix io statistics for cgroup in throttle path brd: mark as nowait compatible brd: check for REQ_NOWAIT and set correct page allocation mask brd: return 0/-error from brd_insert_page() block: sync mixed merged request's failfast with 1st bio's Revert "blk-cgroup: pin the gendisk in struct blkcg_gq" Revert "blk-cgroup: pass a gendisk to blkg_lookup" Revert "blk-cgroup: delay blk-cgroup initialization until add_disk" Revert "blk-cgroup: delay calling blkcg_exit_disk until disk_release" Revert "blk-cgroup: move the cgroup information to struct gendisk" nvme-pci: remove iod use_sgls nvme-pci: fix freeing single sgl block: ublk: check IO buffer based on flag need_get_data s390/dasd: Fix potential memleak in dasd_eckd_init() s390/dasd: sort out physical vs virtual pointers usage block: Remove the ALLOC_CACHE_SLACK constant block: make kobj_type structures constant ...
2023-02-16block: use proper return value from bio_failfast()Jens Axboe
kernel test robot complains about a type mismatch: block/blk-merge.c:984:42: sparse: expected restricted blk_opf_t const [usertype] ff block/blk-merge.c:984:42: sparse: got unsigned int block/blk-merge.c:1010:42: sparse: sparse: incorrect type in initializer (different base types) @@ expected restricted blk_opf_t const [usertype] ff @@ got unsigned int @@ block/blk-merge.c:1010:42: sparse: expected restricted blk_opf_t const [usertype] ff block/blk-merge.c:1010:42: sparse: got unsigned int because bio_failfast() is return an unsigned int rather than the appropriate blk_opt_f type. Fix it up. Fixes: 3ce6a115980c ("block: sync mixed merged request's failfast with 1st bio's") Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/oe-kbuild-all/202302170743.GXypM9Rt-lkp@intel.com/ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-16block: sync mixed merged request's failfast with 1st bio'sMing Lei
We support mixed merge for requests/bios with different fastfail settings. When request fails, each time we only handle the portion with same failfast setting, then bios with failfast can be failed immediately, and bios without failfast can be retried. The idea is pretty good, but the current implementation has several defects: 1) initially RA bio doesn't set failfast, however bio merge code doesn't consider this point, and just check its failfast setting for deciding if mixed merge is required. Fix this issue by adding helper of bio_failfast(). 2) when merging bio to request front, if this request is mixed merged, we have to sync request's faifast setting with 1st bio's failfast. Fix it by calling blk_update_mixed_merge(). 3) when merging bio to request back, if this request is mixed merged, we have to mark the bio as failfast, because blk_update_request simply updates request failfast with 1st bio's failfast. Fix it by calling blk_update_mixed_merge(). Fixes one normal EXT4 READ IO failure issue, because it is observed that the normal READ IO is merged with RA IO, and the mixed merged request has different failfast setting with 1st bio's, so finally the normal READ IO doesn't get retried. Cc: Tejun Heo <tj@kernel.org> Fixes: 80a761fd33cf ("block: implement mixed merge of different failfast requests") Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20230209125527.667004-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-15block: export bio_split_rwChristoph Hellwig
bio_split_rw can be used by file systems to split and incoming write bio into multiple bios fitting the hardware limit for use as ZONE_APPEND bios. Export it for initial use in btrfs. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2023-01-04block: don't allow splitting of a REQ_NOWAIT bioJens Axboe
If we split a bio marked with REQ_NOWAIT, then we can trigger spurious EAGAIN if constituent parts of that split bio end up failing request allocations. Parts will complete just fine, but just a single failure in one of the chained bios will yield an EAGAIN final result for the parent bio. Return EAGAIN early if we end up needing to split such a bio, which allows for saner recovery handling. Cc: stable@vger.kernel.org # 5.15+ Link: https://github.com/axboe/liburing/issues/766 Reported-by: Michael Kelley <mikelley@microsoft.com> Reviewed-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-01-04block: handle bio_split_to_limits() NULL returnJens Axboe
This can't happen right now, but in preparation for allowing bio_split_to_limits() returning NULL if it ended the bio, check for it in all the callers. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-25block: Micro-optimize get_max_segment_size()Bart Van Assche
This patch removes a conditional jump from get_max_segment_size(). The x86-64 assembler code for this function without this patch is as follows: 206 return min_not_zero(mask - offset + 1, 0x0000000000000118 <+72>: not %rax 0x000000000000011b <+75>: and 0x8(%r10),%rax 0x000000000000011f <+79>: add $0x1,%rax 0x0000000000000123 <+83>: je 0x138 <bvec_split_segs+104> 0x0000000000000125 <+85>: cmp %rdx,%rax 0x0000000000000128 <+88>: mov %rdx,%r12 0x000000000000012b <+91>: cmovbe %rax,%r12 0x000000000000012f <+95>: test %rdx,%rdx 0x0000000000000132 <+98>: mov %eax,%edx 0x0000000000000134 <+100>: cmovne %r12d,%edx With this patch applied: 206 return min(mask - offset, (unsigned long)lim->max_segment_size - 1) + 1; 0x000000000000003f <+63>: mov 0x28(%rdi),%ebp 0x0000000000000042 <+66>: not %rax 0x0000000000000045 <+69>: and 0x8(%rdi),%rax 0x0000000000000049 <+73>: sub $0x1,%rbp 0x000000000000004d <+77>: cmp %rbp,%rax 0x0000000000000050 <+80>: cmova %rbp,%rax 0x0000000000000054 <+84>: add $0x1,%eax Reviewed-by: Ming Lei <ming.lei@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Keith Busch <kbusch@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20221025191755.1711437-4-bvanassche@acm.org Reviewed-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-10-25block: Constify most queue limits pointersBart Van Assche
Document which functions do not modify the queue limits. Reviewed-by: Ming Lei <ming.lei@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Keith Busch <kbusch@kernel.org> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20221025191755.1711437-3-bvanassche@acm.org Reviewed-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-02block: pass struct queue_limits to the bio splitting helpersChristoph Hellwig
Allow using the splitting helpers on just a queue_limits instead of a full request_queue structure. This will eventually allow file systems or remapping drivers to split REQ_OP_ZONE_APPEND bios based on limits calculated as the minimum common capabilities over multiple devices. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20220727162300.3089193-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-02block: move bio_allowed_max_sectors to blk-merge.cChristoph Hellwig
Move this helper into the only file where it is used. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20220727162300.3089193-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-02block: move the call to get_max_io_size out of blk_bio_segment_splitChristoph Hellwig
Prepare for reusing blk_bio_segment_split for (file system controlled) splits of REQ_OP_ZONE_APPEND bios by letting the caller control the maximum size of the bio. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20220727162300.3089193-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-02block: move ->bio_split to the gendiskChristoph Hellwig
Only non-passthrough requests are split by the block layer and use the ->bio_split bio_set. Move it from the request_queue to the gendisk. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20220727162300.3089193-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>