kernel/linux.git/drivers/block/rbd.c, branch v6.19.11

rbd: check for EOD after exclusive lock is ensured to be held

2026-02-03T20:00:22+00:00

Similar to commit 870611e4877e ("rbd: get snapshot context after exclusive lock is ensured to be held"), move the "beyond EOD" check into the image request state machine so that it's performed after exclusive lock is ensured to be held. This avoids various race conditions which can arise when the image is shrunk under I/O (in practice, mostly readahead). In one such scenario rbd_assert(objno < rbd_dev->object_map_size); can be triggered if a close-to-EOD read gets queued right before the shrink is initiated and the EOD check is performed against an outdated mapping_size. After the resize is done on the server side and exclusive lock is (re)acquired bringing along the new (now shrunk) object map, the read starts going through the state machine and rbd_obj_may_exist() gets invoked on an object that is out of bounds of rbd_dev->object_map array. Cc: stable@vger.kernel.org Signed-off-by: Ilya Dryomov Reviewed-by: Dongsheng Yang

drivers/block: WQ_PERCPU added to alloc_workqueue users

2025-09-09T15:11:31+00:00

Currently if a user enqueue a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to schedule_work() that is using system_wq and queue_work(), that makes use again of WORK_CPU_UNBOUND. This lack of consistentcy cannot be addressed without refactoring the API. alloc_workqueue() treats all queues as per-CPU by default, while unbound workqueues must opt-in via WQ_UNBOUND. This default is suboptimal: most workloads benefit from unbound queues, allowing the scheduler to place worker threads where they’re needed and reducing noise when CPUs are isolated. This default is suboptimal: most workloads benefit from unbound queues, allowing the scheduler to place worker threads where they’re needed and reducing noise when CPUs are isolated. This patch adds a new WQ_PERCPU flag to explicitly request the use of the per-CPU behavior. Both flags coexist for one release cycle to allow callers to transition their calls. Once migration is complete, WQ_UNBOUND can be removed and unbound will become the implicit default. With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND), any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND must now use WQ_PERCPU. All existing users have been updated accordingly. Suggested-by: Tejun Heo Signed-off-by: Marco Crivellari Signed-off-by: Jens Axboe

block: force noio scope in blk_mq_freeze_queue

2025-01-31T14:20:08+00:00

When block drivers or the core block code perform allocations with a frozen queue, this could try to recurse into the block device to reclaim memory and deadlock. Thus all allocations done by a process that froze a queue need to be done without __GFP_IO and __GFP_FS. Instead of tying to track all of them down, force a noio scope as part of freezing the queue. Note that nvme is a bit of a mess here due to the non-owner freezes, and they will be addressed separately. Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20250131120352.1315351-2-hch@lst.de Signed-off-by: Jens Axboe

block: remove BLK_MQ_F_SHOULD_MERGE

2024-12-23T15:17:23+00:00

BLK_MQ_F_SHOULD_MERGE is set for all tag_sets except those that purely process passthrough commands (bsg-lib, ufs tmf, various nvme admin queues) and thus don't even check the flag. Remove it to simplify the driver interface. Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20241219060214.1928848-1-hch@lst.de Signed-off-by: Jens Axboe

rbd: unfreeze queue after marking disk as dead

2024-11-07T23:27:22+00:00

Unfreeze queue after returning from blk_mark_disk_dead(), this way at least allows us to verify queue freeze correctly with lockdep. Suggested-by: Christoph Hellwig Cc: Ilya Dryomov Signed-off-by: Ming Lei Link: https://lore.kernel.org/r/20241031133723.303835-3-ming.lei@redhat.com Signed-off-by: Jens Axboe

Merge tag 'ceph-for-6.11-rc1' of https://github.com/ceph/ceph-client

2024-07-26T17:34:42+00:00

Pull ceph updates from Ilya Dryomov: "A small patchset to address bogus I/O errors and ultimately an assertion failure in the face of watch errors with -o exclusive mappings in RBD marked for stable and some assorted CephFS fixes" * tag 'ceph-for-6.11-rc1' of https://github.com/ceph/ceph-client: rbd: don't assume rbd_is_lock_owner() for exclusive mappings rbd: don't assume RBD_LOCK_STATE_LOCKED for exclusive mappings rbd: rename RBD_LOCK_STATE_RELEASING and releasing_wait ceph: fix incorrect kmalloc size of pagevec mempool ceph: periodically flush the cap releases ceph: convert comma to semicolon in __ceph_dentry_dir_lease_touch() ceph: use cap_wait_list only if debugfs is enabled

rbd: don't assume rbd_is_lock_owner() for exclusive mappings

2024-07-25T10:18:29+00:00

Expanding on the previous commit, assuming that rbd_is_lock_owner() always returns true (i.e. that we are either in RBD_LOCK_STATE_LOCKED or RBD_LOCK_STATE_QUIESCING) if the mapping is exclusive is wrong too. In case ceph_cls_set_cookie() fails, the lock would be temporarily released even if the mapping is exclusive, meaning that we can end up even in RBD_LOCK_STATE_UNLOCKED. IOW, exclusive mappings are really "just" about disabling automatic lock transitions (as documented in the man page), not about grabbing the lock and holding on to it whatever it takes. Cc: stable@vger.kernel.org Fixes: 637cd060537d ("rbd: new exclusive lock wait/wake code") Signed-off-by: Ilya Dryomov Reviewed-by: Dongsheng Yang

rbd: don't assume RBD_LOCK_STATE_LOCKED for exclusive mappings

2024-07-25T10:18:28+00:00

Every time a watch is reestablished after getting lost, we need to update the cookie which involves quiescing exclusive lock. For this, we transition from RBD_LOCK_STATE_LOCKED to RBD_LOCK_STATE_QUIESCING roughly for the duration of rbd_reacquire_lock() call. If the mapping is exclusive and I/O happens to arrive in this time window, it's failed with EROFS (later translated to EIO) based on the wrong assumption in rbd_img_exclusive_lock() -- "lock got released?" check there stopped making sense with commit a2b1da09793d ("rbd: lock should be quiesced on reacquire"). To make it worse, any such I/O is added to the acquiring list before EROFS is returned and this sets up for violating rbd_lock_del_request() precondition that the request is either on the running list or not on any list at all -- see commit ded080c86b3f ("rbd: don't move requests to the running list on errors"). rbd_lock_del_request() ends up processing these requests as if they were on the running list which screws up quiescing_wait completion counter and ultimately leads to rbd_assert(!completion_done(&rbd_dev->quiescing_wait)); being triggered on the next watch error. Cc: stable@vger.kernel.org # 06ef84c4e9c4: rbd: rename RBD_LOCK_STATE_RELEASING and releasing_wait Cc: stable@vger.kernel.org Fixes: 637cd060537d ("rbd: new exclusive lock wait/wake code") Signed-off-by: Ilya Dryomov Reviewed-by: Dongsheng Yang

rbd: rename RBD_LOCK_STATE_RELEASING and releasing_wait

2024-07-25T10:18:01+00:00

... to RBD_LOCK_STATE_QUIESCING and quiescing_wait to recognize that this state and the associated completion are backing rbd_quiesce_lock(), which isn't specific to releasing the lock. While exclusive lock does get quiesced before it's released, it also gets quiesced before an attempt to update the cookie is made and there the lock is not released as long as ceph_cls_set_cookie() succeeds. Signed-off-by: Ilya Dryomov Reviewed-by: Dongsheng Yang

block: move the stable_writes flag to queue_limits

2024-06-19T13:58:28+00:00

Move the stable_writes flag into the queue_limits feature field so that it can be set atomically with the queue frozen. The flag is now inherited by blk_stack_limits, which greatly simplifies the code in dm, and fixed md which previously did not pass on the flag set on lower devices. Signed-off-by: Christoph Hellwig Reviewed-by: Damien Le Moal Reviewed-by: Hannes Reinecke Link: https://lore.kernel.org/r/20240617060532.127975-18-hch@lst.de Signed-off-by: Jens Axboe