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2024-03-06drbd: refactor the backing dev max_segments calculationChristoph Hellwig1-8/+17
Factor out a drbd_backing_dev_max_segments helper that checks the backing device limitation. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Philipp Reisner <philipp.reisner@linbit.com> Reviewed-by: Lars Ellenberg <lars.ellenberg@linbit.com> Tested-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Link: https://lore.kernel.org/r/20240306140332.623759-4-philipp.reisner@linbit.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-06drbd: refactor drbd_reconsider_queue_parametersChristoph Hellwig1-35/+49
Split out a drbd_max_peer_bio_size helper for the peer I/O size, and condense the various checks to a nested min3(..., max())) instead of using a lot of local variables. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240305134041.137006-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-06drbd: pass the max_hw_sectors limit to blk_alloc_diskChristoph Hellwig1-4/+9
Pass a queue_limits structure with the max_hw_sectors limit to blk_alloc_disk instead of updating the limit on the allocated gendisk. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240305134041.137006-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-06sed-opal: Remove the ret variable from the functionLi kunyu1-4/+2
The ret variable in the function has not yet been effective and can be removed. Signed-off-by: Li kunyu <kunyu@nfschina.com> Link: https://lore.kernel.org/r/20240306101444.1244-1-kunyu@nfschina.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-06sed-opal: Remove unnecessary ‘0’ values from retLi kunyu1-2/+2
ret is assigned first, so it does not need to initialize the assignment. Signed-off-by: Li kunyu <kunyu@nfschina.com> Link: https://lore.kernel.org/r/20240306100659.106521-1-kunyu@nfschina.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-06sed-opal: Remove unnecessary ‘0’ values from errLi zeming1-1/+1
err is assigned first, so it does not need to initialize the assignment. Signed-off-by: Li zeming <zeming@nfschina.com> Link: https://lore.kernel.org/r/20240306100216.69340-1-zeming@nfschina.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-06sed-opal: Remove unnecessary ‘0’ values from errorLi zeming1-2/+2
error is assigned first, so it does not need to initialize the assignment. Signed-off-by: Li zeming <zeming@nfschina.com> Link: https://lore.kernel.org/r/20240306095608.26839-1-zeming@nfschina.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-06block: make block_class constantRicardo B. Marliere3-3/+3
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>
2024-03-06dasd: use the atomic queue limits APIChristoph Hellwig2-18/+24
Pass the constant limits directly to blk_mq_alloc_disk, set the nonrot flag there as well, and then use the commit API to change the transfer size and logical block size dependent values. This relies on the assumption that no I/O can be pending before the devices moves into the ready state and doesn't need extra freezing for changes to the queue limits. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Stefan Haberland <sth@linux.ibm.com> Link: https://lore.kernel.org/r/20240228133742.806274-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-06dasd: move queue setup to common codeChristoph Hellwig5-77/+42
Most of the code in setup_blk_queue is shared between all disciplines. Move it to common code and leave a method to query the maximum number of transferable blocks, and a flag to indicate discard support. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Stefan Haberland <sth@linux.ibm.com> Link: https://lore.kernel.org/r/20240228133742.806274-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-06dasd: cleamup dasd_state_basic_to_readyChristoph Hellwig1-28/+26
Reflow dasd_state_basic_to_ready a bit to make it easier to modify. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Stefan Haberland <sth@linux.ibm.com> Link: https://lore.kernel.org/r/20240228133742.806274-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-06block: Fix page refcounts for unaligned buffers in __bio_release_pages()Tony Battersby1-3/+4
Fix an incorrect number of pages being released for buffers that do not start at the beginning of a page. Fixes: 1b151e2435fc ("block: Remove special-casing of compound pages") Cc: stable@vger.kernel.org Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Tested-by: Greg Edwards <gedwards@ddn.com> Link: https://lore.kernel.org/r/86e592a9-98d4-4cff-a646-0c0084328356@cybernetics.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-05dm-raid: fix lockdep waring in "pers->hot_add_disk"Yu Kuai1-0/+2
The lockdep assert is added by commit a448af25becf ("md/raid10: remove rcu protection to access rdev from conf") in print_conf(). And I didn't notice that dm-raid is calling "pers->hot_add_disk" without holding 'reconfig_mutex'. "pers->hot_add_disk" read and write many fields that is protected by 'reconfig_mutex', and raid_resume() already grab the lock in other contex. Hence fix this problem by protecting "pers->host_add_disk" with the lock. Fixes: 9092c02d9435 ("DM RAID: Add ability to restore transiently failed devices on resume") Fixes: a448af25becf ("md/raid10: remove rcu protection to access rdev from conf") Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Xiao Ni <xni@redhat.com> Acked-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240305072306.2562024-10-yukuai1@huaweicloud.com
2024-03-05dm-raid456, md/raid456: fix a deadlock for dm-raid456 while io concurrent ↵Yu Kuai4-7/+74
with reshape For raid456, if reshape is still in progress, then IO across reshape position will wait for reshape to make progress. However, for dm-raid, in following cases reshape will never make progress hence IO will hang: 1) the array is read-only; 2) MD_RECOVERY_WAIT is set; 3) MD_RECOVERY_FROZEN is set; After commit c467e97f079f ("md/raid6: use valid sector values to determine if an I/O should wait on the reshape") fix the problem that IO across reshape position doesn't wait for reshape, the dm-raid test shell/lvconvert-raid-reshape.sh start to hang: [root@fedora ~]# cat /proc/979/stack [<0>] wait_woken+0x7d/0x90 [<0>] raid5_make_request+0x929/0x1d70 [raid456] [<0>] md_handle_request+0xc2/0x3b0 [md_mod] [<0>] raid_map+0x2c/0x50 [dm_raid] [<0>] __map_bio+0x251/0x380 [dm_mod] [<0>] dm_submit_bio+0x1f0/0x760 [dm_mod] [<0>] __submit_bio+0xc2/0x1c0 [<0>] submit_bio_noacct_nocheck+0x17f/0x450 [<0>] submit_bio_noacct+0x2bc/0x780 [<0>] submit_bio+0x70/0xc0 [<0>] mpage_readahead+0x169/0x1f0 [<0>] blkdev_readahead+0x18/0x30 [<0>] read_pages+0x7c/0x3b0 [<0>] page_cache_ra_unbounded+0x1ab/0x280 [<0>] force_page_cache_ra+0x9e/0x130 [<0>] page_cache_sync_ra+0x3b/0x110 [<0>] filemap_get_pages+0x143/0xa30 [<0>] filemap_read+0xdc/0x4b0 [<0>] blkdev_read_iter+0x75/0x200 [<0>] vfs_read+0x272/0x460 [<0>] ksys_read+0x7a/0x170 [<0>] __x64_sys_read+0x1c/0x30 [<0>] do_syscall_64+0xc6/0x230 [<0>] entry_SYSCALL_64_after_hwframe+0x6c/0x74 This is because reshape can't make progress. For md/raid, the problem doesn't exist because register new sync_thread doesn't rely on the IO to be done any more: 1) If array is read-only, it can switch to read-write by ioctl/sysfs; 2) md/raid never set MD_RECOVERY_WAIT; 3) If MD_RECOVERY_FROZEN is set, mddev_suspend() doesn't hold 'reconfig_mutex', hence it can be cleared and reshape can continue by sysfs api 'sync_action'. However, I'm not sure yet how to avoid the problem in dm-raid yet. This patch on the one hand make sure raid_message() can't change sync_thread() through raid_message() after presuspend(), on the other hand detect the above 3 cases before wait for IO do be done in dm_suspend(), and let dm-raid requeue those IO. Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Xiao Ni <xni@redhat.com> Acked-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240305072306.2562024-9-yukuai1@huaweicloud.com
2024-03-05dm-raid: add a new helper prepare_suspend() in md_personalityYu Kuai2-0/+19
There are no functional changes for now, prepare to fix a deadlock for dm-raid456. Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Xiao Ni <xni@redhat.com> Acked-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240305072306.2562024-8-yukuai1@huaweicloud.com
2024-03-05md/dm-raid: don't call md_reap_sync_thread() directlyYu Kuai1-10/+18
Currently md_reap_sync_thread() is called from raid_message() directly without holding 'reconfig_mutex', this is definitely unsafe because md_reap_sync_thread() can change many fields that is protected by 'reconfig_mutex'. However, hold 'reconfig_mutex' here is still problematic because this will cause deadlock, for example, commit 130443d60b1b ("md: refactor idle/frozen_sync_thread() to fix deadlock"). Fix this problem by using stop_sync_thread() to unregister sync_thread, like md/raid did. Fixes: be83651f0050 ("DM RAID: Add message/status support for changing sync action") Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Xiao Ni <xni@redhat.com> Acked-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240305072306.2562024-7-yukuai1@huaweicloud.com
2024-03-05dm-raid: really frozen sync_thread during suspendYu Kuai2-11/+17
1) commit f52f5c71f3d4 ("md: fix stopping sync thread") remove MD_RECOVERY_FROZEN from __md_stop_writes() and doesn't realize that dm-raid relies on __md_stop_writes() to frozen sync_thread indirectly. Fix this problem by adding MD_RECOVERY_FROZEN in md_stop_writes(), and since stop_sync_thread() is only used for dm-raid in this case, also move stop_sync_thread() to md_stop_writes(). 2) The flag MD_RECOVERY_FROZEN doesn't mean that sync thread is frozen, it only prevent new sync_thread to start, and it can't stop the running sync thread; In order to frozen sync_thread, after seting the flag, stop_sync_thread() should be used. 3) The flag MD_RECOVERY_FROZEN doesn't mean that writes are stopped, use it as condition for md_stop_writes() in raid_postsuspend() doesn't look correct. Consider that reentrant stop_sync_thread() do nothing, always call md_stop_writes() in raid_postsuspend(). 4) raid_message can set/clear the flag MD_RECOVERY_FROZEN at anytime, and if MD_RECOVERY_FROZEN is cleared while the array is suspended, new sync_thread can start unexpected. Fix this by disallow raid_message() to change sync_thread status during suspend. Note that after commit f52f5c71f3d4 ("md: fix stopping sync thread"), the test shell/lvconvert-raid-reshape.sh start to hang in stop_sync_thread(), and with previous fixes, the test won't hang there anymore, however, the test will still fail and complain that ext4 is corrupted. And with this patch, the test won't hang due to stop_sync_thread() or fail due to ext4 is corrupted anymore. However, there is still a deadlock related to dm-raid456 that will be fixed in following patches. Reported-by: Mikulas Patocka <mpatocka@redhat.com> Closes: https://lore.kernel.org/all/e5e8afe2-e9a8-49a2-5ab0-958d4065c55e@redhat.com/ Fixes: 1af2048a3e87 ("dm raid: fix deadlock caused by premature md_stop_writes()") Fixes: 9dbd1aa3a81c ("dm raid: add reshaping support to the target") Fixes: f52f5c71f3d4 ("md: fix stopping sync thread") Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Xiao Ni <xni@redhat.com> Acked-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240305072306.2562024-6-yukuai1@huaweicloud.com
2024-03-05md: add a new helper reshape_interrupted()Yu Kuai1-0/+19
The helper will be used for dm-raid456 later to detect the case that reshape can't make progress. Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Xiao Ni <xni@redhat.com> Acked-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240305072306.2562024-5-yukuai1@huaweicloud.com
2024-03-05md: export helper md_is_rdwr()Yu Kuai2-12/+12
There are no functional changes for now, prepare to fix a deadlock for dm-raid456. Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Xiao Ni <xni@redhat.com> Acked-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240305072306.2562024-4-yukuai1@huaweicloud.com
2024-03-05md: export helpers to stop sync_threadYu Kuai2-0/+32
Add new helpers: void md_idle_sync_thread(struct mddev *mddev); void md_frozen_sync_thread(struct mddev *mddev); void md_unfrozen_sync_thread(struct mddev *mddev); The helpers will be used in dm-raid in later patches to fix regressions and prevent calling md_reap_sync_thread() directly. Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Xiao Ni <xni@redhat.com> Acked-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240305072306.2562024-3-yukuai1@huaweicloud.com
2024-03-05md: don't clear MD_RECOVERY_FROZEN for new dm-raid until resumeYu Kuai1-1/+4
After commit 9dbd1aa3a81c ("dm raid: add reshaping support to the target") raid_ctr() will set MD_RECOVERY_FROZEN before md_run() and expect to keep array frozen until resume. However, md_run() will clear the flag by setting mddev->recovery to 0. Before commit 1baae052cccd ("md: Don't ignore suspended array in md_check_recovery()"), dm-raid actually relied on suspending to prevent starting new sync_thread. Fix this problem by keeping 'MD_RECOVERY_FROZEN' for dm-raid in md_run(). Fixes: 1baae052cccd ("md: Don't ignore suspended array in md_check_recovery()") Fixes: 9dbd1aa3a81c ("dm raid: add reshaping support to the target") Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Xiao Ni <xni@redhat.com> Acked-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240305072306.2562024-2-yukuai1@huaweicloud.com
2024-03-05Revert "Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d""Song Liu1-0/+12
This reverts commit bed9e27baf52a09b7ba2a3714f1e24e17ced386d. The original set [1][2] was expected to undo a suboptimal fix in [2], and replace it with a better fix [1]. However, as reported by Dan Moulding [2] causes an issue with raid5 with journal device. Revert [2] for now to close the issue. We will follow up on another issue reported by Juxiao Bi, as [2] is expected to fix it. We believe this is a good trade-off, because the latter issue happens less freqently. In the meanwhile, we will NOT revert [1], as it contains the right logic. [1] commit d6e035aad6c0 ("md: bypass block throttle for superblock update") [2] commit bed9e27baf52 ("Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"") Reported-by: Dan Moulding <dan@danm.net> Closes: https://lore.kernel.org/linux-raid/20240123005700.9302-1-dan@danm.net/ Fixes: bed9e27baf52 ("Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"") Cc: stable@vger.kernel.org # v5.19+ Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20240125082131.788600-1-song@kernel.org
2024-03-01nbd: use the atomic queue limits API in nbd_set_sizeChristoph Hellwig1-4/+11
Use queue_limits_start_update / queue_limits_commit_update to update all the limits in one go and with proper sanity checking. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240229143846.1047223-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-01nbd: freeze the queue for queue limits updatesChristoph Hellwig1-1/+13
nbd currently updates the logical and physical block sizes as well as the discard_sectors on a live queue. Freeze the queue first to make sure there are not commands in flight that can see torn or inconsistent limits. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240229143846.1047223-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-01nbd: don't clear discard_sectors in nbd_config_putChristoph Hellwig1-1/+2
nbd_config_put currently clears discard_sectors when unusing a device. This is pretty odd behavior and different from the sector size configuration which is simply left in places and then reconfigured when nbd_set_size is as part of configuring the device. Change nbd_set_size to clear discard_sectors if discard is not supported so that all the queue limits changes are handled in one place. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240229143846.1047223-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-01pktcdvd: don't set max_hw_sectors on the underlying deviceChristoph Hellwig1-5/+6
pktcdvd sets max_hw_sectors on the queue of the underlying device that it doesn't own (and doesn't reset it ever) since the driver was merged. This can create all kinds of problems as the underlying driver doesn't even know about it changing the limit. As the state purpose is to not create I/Os larger than a single frame, and pktcdvd never builds bios larger than that, just set REQ_NOMERGE on the bios it submits so that largers I/Os never get built. Note: I don't have packet writing hardware, so this is compile tested only. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240229144408.1047967-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-01dm: use queue_limits_setChristoph Hellwig2-16/+13
Use queue_limits_set which validates the limits and takes care of updating the readahead settings instead of directly assigning them to the queue. For that make sure all limits are actually updated before the assignment. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@kernel.org> Link: https://lore.kernel.org/r/20240228225653.947152-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-03-01block: add a queue_limits_stack_bdev helperChristoph Hellwig2-0/+27
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 Hellwig2-0/+19
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>
2024-03-01md/raid1: factor out helpers to choose the best rdev from read_balance()Yu Kuai1-77/+98
The way that best rdev is chosen: 1) If the read is sequential from one rdev: - if rdev is rotational, use this rdev; - if rdev is non-rotational, use this rdev until total read length exceed disk opt io size; 2) If the read is not sequential: - if there is idle disk, use it, otherwise: - if the array has non-rotational disk, choose the rdev with minimal inflight IO; - if all the underlaying disks are rotational disk, choose the rdev with closest IO; There are no functional changes, just to make code cleaner and prepare for following refactor. Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-12-yukuai1@huaweicloud.com
2024-03-01md/raid1: factor out the code to manage sequential IOYu Kuai1-34/+37
There is no functional change for now, make read_balance() cleaner and prepare to fix problems and refactor the handler of sequential IO. Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-11-yukuai1@huaweicloud.com
2024-03-01md/raid1: factor out choose_bb_rdev() from read_balance()Yu Kuai1-31/+48
read_balance() is hard to understand because there are too many status and branches, and it's overlong. This patch factor out the case to read the rdev with bad blocks from read_balance(), there are no functional changes. Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-10-yukuai1@huaweicloud.com
2024-03-01md/raid1: factor out choose_slow_rdev() from read_balance()Yu Kuai1-17/+52
read_balance() is hard to understand because there are too many status and branches, and it's overlong. This patch factor out the case to read the slow rdev from read_balance(), there are no functional changes. Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-9-yukuai1@huaweicloud.com
2024-03-01md/raid1: factor out read_first_rdev() from read_balance()Yu Kuai1-17/+46
read_balance() is hard to understand because there are too many status and branches, and it's overlong. This patch factor out the case to read the first rdev from read_balance(), there are no functional changes. Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-8-yukuai1@huaweicloud.com
2024-03-01md/raid1-10: factor out a new helper raid1_should_read_first()Yu Kuai3-24/+24
If resync is in progress, read_balance() should find the first usable disk, otherwise, data could be inconsistent after resync is done. raid1 and raid10 implement the same checking, hence factor out the checking to make code cleaner. Noted that raid1 is using 'mddev->recovery_cp', which is updated after all resync IO is done, while raid10 is using 'conf->next_resync', which is inaccurate because raid10 update it before submitting resync IO. Fortunately, raid10 read IO can't concurrent with resync IO, hence there is no problem. And this patch also switch raid10 to use 'mddev->recovery_cp'. Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-7-yukuai1@huaweicloud.com
2024-03-01md/raid1-10: add a helper raid1_check_read_range()Yu Kuai1-0/+49
The checking and handler of bad blocks appear many timers during read_balance() in raid1 and raid10. This helper will be used in later patches to simplify read_balance() a lot. Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-6-yukuai1@huaweicloud.com
2024-03-01md/raid1: fix choose next idle in read_balance()Yu Kuai1-10/+22
Commit 12cee5a8a29e ("md/raid1: prevent merging too large request") add the case choose next idle in read_balance(): read_balance: for_each_rdev if(next_seq_sect == this_sector || dist == 0) -> sequential reads best_disk = disk; if (...) choose_next_idle = 1 continue; for_each_rdev -> iterate next rdev if (pending == 0) best_disk = disk; -> choose the next idle disk break; if (choose_next_idle) -> keep using this rdev if there are no other idle disk contine However, commit 2e52d449bcec ("md/raid1: add failfast handling for reads.") remove the code: - /* If device is idle, use it */ - if (pending == 0) { - best_disk = disk; - break; - } Hence choose next idle will never work now, fix this problem by following: 1) don't set best_disk in this case, read_balance() will choose the best disk after iterating all the disks; 2) add 'pending' so that other idle disk will be chosen; 3) add a new local variable 'sequential_disk' to record the disk, and if there is no other idle disk, 'sequential_disk' will be chosen; Fixes: 2e52d449bcec ("md/raid1: add failfast handling for reads.") Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-5-yukuai1@huaweicloud.com
2024-03-01md/raid1: record nonrot rdevs while adding/removing rdevs to confYu Kuai3-7/+12
For raid1, each read will iterate all the rdevs from conf and check if any rdev is non-rotational, then choose rdev with minimal IO inflight if so, or rdev with closest distance otherwise. Disk nonrot info can be changed through sysfs entry: /sys/block/[disk_name]/queue/rotational However, consider that this should only be used for testing, and user really shouldn't do this in real life. Record the number of non-rotational disks in conf, to avoid checking each rdev in IO fast path and simplify read_balance() a little bit. Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-4-yukuai1@huaweicloud.com
2024-03-01md/raid1: factor out helpers to add rdev to confYu Kuai1-32/+53
There are no functional changes, just make code cleaner and prepare to record disk non-rotational information while adding and removing rdev to conf Signed-off-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-3-yukuai1@huaweicloud.com
2024-03-01md: add a new helper rdev_has_badblock()Yu Kuai4-72/+44
The current api is_badblock() must pass in 'first_bad' and 'bad_sectors', however, many caller just want to know if there are badblocks or not, and these caller must define two local variable that will never be used. Add a new helper rdev_has_badblock() that will only return if there are badblocks or not, remove unnecessary local variables and replace is_badblock() with the new helper in many places. There are no functional changes, and the new helper will also be used later to refactor read_balance(). Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-2-yukuai1@huaweicloud.com
2024-02-29ublk: add UBLK_CMD_DEL_DEV_ASYNCMing Lei2-3/+8
The current command UBLK_CMD_DEL_DEV won't return until the device is released, this way looks more reliable, but makes userspace more difficult to implement, especially about orders: unmap command buffer(which holds one ublkc reference), ublkc close, io_uring_file_unregister, ublkb close. Add UBLK_CMD_DEL_DEV_ASYNC so that device deletion won't wait release, then userspace needn't worry about the above order. Actually both loop and nbd is deleted in this async way. Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20240223075539.89945-3-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-29ublk: improve getting & putting ublk deviceMing Lei1-5/+7
Firstly convert get_device() and put_device() into ublk_get_device() and ublk_put_device(). Secondly annotate ublk_get_device() & ublk_put_device() as noinline for trace, especially it is often to trigger device deletion hang when incorrect order is used on ublkc mmap, ublkc close, io_uring_sqe_unregister_file, ublkb close. Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20240223075539.89945-2-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-28blk-mq: don't change nr_hw_queues and nr_maps for kdump kernelMing Lei1-8/+6
For most of ARCHs, 'nr_cpus=1' is passed for kdump kernel, so nr_hw_queues for each mapping is supposed to be 1 already. More importantly, this way may cause trouble for driver, because blk-mq and driver see different queue mapping since driver should setup hardware queue setting before calling into allocating blk-mq tagset. So not overriding nr_hw_queues and nr_maps for kdump kernel. Cc: Wen Xiong <wenxiong@us.ibm.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20240228040857.306483-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-27md/raid5: fix atomicity violation in raid5_cache_countGui-Dong Han1-6/+8
In raid5_cache_count(): if (conf->max_nr_stripes < conf->min_nr_stripes) return 0; return conf->max_nr_stripes - conf->min_nr_stripes; The current check is ineffective, as the values could change immediately after being checked. In raid5_set_cache_size(): ... conf->min_nr_stripes = size; ... while (size > conf->max_nr_stripes) conf->min_nr_stripes = conf->max_nr_stripes; ... Due to intermediate value updates in raid5_set_cache_size(), concurrent execution of raid5_cache_count() and raid5_set_cache_size() may lead to inconsistent reads of conf->max_nr_stripes and conf->min_nr_stripes. The current checks are ineffective as values could change immediately after being checked, raising the risk of conf->min_nr_stripes exceeding conf->max_nr_stripes and potentially causing an integer overflow. This possible bug is found by an experimental static analysis tool developed by our team. This tool analyzes the locking APIs to extract function pairs that can be concurrently executed, and then analyzes the instructions in the paired functions to identify possible concurrency bugs including data races and atomicity violations. The above possible bug is reported when our tool analyzes the source code of Linux 6.2. To resolve this issue, it is suggested to introduce local variables 'min_stripes' and 'max_stripes' in raid5_cache_count() to ensure the values remain stable throughout the check. Adding locks in raid5_cache_count() fails to resolve atomicity violations, as raid5_set_cache_size() may hold intermediate values of conf->min_nr_stripes while unlocked. With this patch applied, our tool no longer reports the bug, with the kernel configuration allyesconfig for x86_64. Due to the lack of associated hardware, we cannot test the patch in runtime testing, and just verify it according to the code logic. Fixes: edbe83ab4c27 ("md/raid5: allow the stripe_cache to grow and shrink.") Cc: stable@vger.kernel.org Signed-off-by: Gui-Dong Han <2045gemini@gmail.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240112071017.16313-1-2045gemini@gmail.com Signed-off-by: Song Liu <song@kernel.org>
2024-02-27ubd: open the backing files in ubd_addChristoph Hellwig1-42/+16
Opening the backing device only when the block device is opened is a bit weird as no one configures block devices to not use them. Opend them at add time, close them at remove time and remove the now superflous opened counter as remove can simply check for disk_openers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Richard Weinberger <richard@nod.at> Link: https://lore.kernel.org/r/20240222072417.3773131-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-27ubd: remove the queue pointer in struct ubdChristoph Hellwig1-3/+1
No need for it now, everything goes through the gendisk. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Richard Weinberger <richard@nod.at> Link: https://lore.kernel.org/r/20240222072417.3773131-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-27ubd: move set_disk_ro to ubd_addChristoph Hellwig1-1/+1
No need to delay this until open time. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Richard Weinberger <richard@nod.at> Link: https://lore.kernel.org/r/20240222072417.3773131-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-27ubd: move setting the variable queue limits to ubd_addChristoph Hellwig1-6/+7
No reason to delay this until open time. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Richard Weinberger <richard@nod.at> Link: https://lore.kernel.org/r/20240222072417.3773131-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-27ubd: move setting the nonrot flag to ubd_addChristoph Hellwig1-1/+1
No reason to delay this until open time. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Richard Weinberger <richard@nod.at> Link: https://lore.kernel.org/r/20240222072417.3773131-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-27ubd: remove ubd_disk_registerChristoph Hellwig1-22/+15
Fold it into the only caller to remove lots of references to the global ubd_devs array. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Richard Weinberger <richard@nod.at> Link: https://lore.kernel.org/r/20240222072417.3773131-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>