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2023-05-17block: Skip destroyed blkg when restart in blkg_destroy_all()Tao Su1-0/+3
[ Upstream commit 8176080d59e6d4ff9fc97ae534063073b4f7a715 ] Kernel hang in blkg_destroy_all() when total blkg greater than BLKG_DESTROY_BATCH_SIZE, because of not removing destroyed blkg in blkg_list. So the size of blkg_list is same after destroying a batch of blkg, and the infinite 'restart' occurs. Since blkg should stay on the queue list until blkg_free_workfn(), skip destroyed blkg when restart a new round, which will solve this kernel hang issue and satisfy the previous will to restart. Reported-by: Xiangfei Ma <xiangfeix.ma@intel.com> Tested-by: Xiangfei Ma <xiangfeix.ma@intel.com> Tested-by: Farrah Chen <farrah.chen@intel.com> Signed-off-by: Tao Su <tao1.su@linux.intel.com> Fixes: f1c006f1c685 ("blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and blkcg_deactivate_policy()") Suggested-and-reviewed-by: Yu Kuai <yukuai3@huawei.com> Link: https://lore.kernel.org/r/20230428045149.1310073-1-tao1.su@linux.intel.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11Revert "blk-cgroup: dropping parent refcount after pd_free_fn() is done"Greg Kroah-Hartman1-2/+2
This reverts commit 029f1f1efa84387474b445dac4281cf95a398db8 which is commit c7241babf0855d8a6180cd1743ff0ec34de40b4e upstream. It is reported to cause problems, as only 2 of the 3 patch series were applied to the stable branches. Reported-by: Mike Cloaked <mike.cloaked@gmail.com> Reported-by: Eric Biggers <ebiggers@kernel.org> Cc: Yu Kuai <yukuai3@huawei.com> Cc: Tejun Heo <tj@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Sasha Levin <sashal@kernel.org> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217174 Link: https://lore.kernel.org/r/ZAuPkCn49urWBN5P@sol.localdomain Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-11Revert "blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and ↵Greg Kroah-Hartman1-29/+6
blkcg_deactivate_policy()" This reverts commit 81c1188905f88b77743d1fdeeedfc8cb7b67787d which is commit f1c006f1c6850c14040f8337753a63119bba39b9 upstream. It is reported to cause problems, as only 2 of the 3 patch series were applied to the stable branches. Reported-by: Mike Cloaked <mike.cloaked@gmail.com> Reported-by: Eric Biggers <ebiggers@kernel.org> Cc: Yu Kuai <yukuai3@huawei.com> Cc: Tejun Heo <tj@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: Sasha Levin <sashal@kernel.org> Link: https://bugzilla.kernel.org/show_bug.cgi?id=217174 Link: https://lore.kernel.org/r/ZAuPkCn49urWBN5P@sol.localdomain Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-10blk-cgroup: synchronize pd_free_fn() from blkg_free_workfn() and ↵Yu Kuai1-6/+29
blkcg_deactivate_policy() [ Upstream commit f1c006f1c6850c14040f8337753a63119bba39b9 ] Currently parent pd can be freed before child pd: t1: remove cgroup C1 blkcg_destroy_blkgs blkg_destroy list_del_init(&blkg->q_node) // remove blkg from queue list percpu_ref_kill(&blkg->refcnt) blkg_release call_rcu t2: from t1 __blkg_release blkg_free schedule_work t4: deactivate policy blkcg_deactivate_policy pd_free_fn // parent of C1 is freed first t3: from t2 blkg_free_workfn pd_free_fn If policy(for example, ioc_timer_fn() from iocost) access parent pd from child pd after pd_offline_fn(), then UAF can be triggered. Fix the problem by delaying 'list_del_init(&blkg->q_node)' from blkg_destroy() to blkg_free_workfn(), and using a new disk level mutex to synchronize blkg_free_workfn() and blkcg_deactivate_policy(). Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230119110350.2287325-4-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-10blk-cgroup: dropping parent refcount after pd_free_fn() is doneYu Kuai1-2/+2
[ Upstream commit c7241babf0855d8a6180cd1743ff0ec34de40b4e ] Some cgroup policies will access parent pd through child pd even after pd_offline_fn() is done. If pd_free_fn() for parent is called before child, then UAF can be triggered. Hence it's better to guarantee the order of pd_free_fn(). Currently refcount of parent blkg is dropped in __blkg_release(), which is before pd_free_fn() is called in blkg_free_work_fn() while blkg_free_work_fn() is called asynchronously. This patch make sure pd_free_fn() called from removing cgroup is ordered by delaying dropping parent refcount after calling pd_free_fn() for child. BTW, pd_free_fn() will also be called from blkcg_deactivate_policy() from deleting device, and following patches will guarantee the order. Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20230119110350.2287325-2-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-06blk-cgroup: fix missing pd_online_fn() while activating policyYu Kuai1-0/+4
[ Upstream commit e3ff8887e7db757360f97634e0d6f4b8e27a8c46 ] If the policy defines pd_online_fn(), it should be called after pd_init_fn(), like blkg_create(). Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20230103112833.2013432-1-yukuai1@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31blk-iolatency: Fix memory leak on add_disk() failuresTejun Heo1-0/+2
commit 813e693023ba10da9e75067780f8378465bf27cc upstream. When a gendisk is successfully initialized but add_disk() fails such as when a loop device has invalid number of minor device numbers specified, blkcg_init_disk() is called during init and then blkcg_exit_disk() during error handling. Unfortunately, iolatency gets initialized in the former but doesn't get cleaned up in the latter. This is because, in non-error cases, the cleanup is performed by del_gendisk() calling rq_qos_exit(), the assumption being that rq_qos policies, iolatency being one of them, can only be activated once the disk is fully registered and visible. That assumption is true for wbt and iocost, but not so for iolatency as it gets initialized before add_disk() is called. It is desirable to lazy-init rq_qos policies because they are optional features and add to hot path overhead once initialized - each IO has to walk all the registered rq_qos policies. So, we want to switch iolatency to lazy init too. However, that's a bigger change. As a fix for the immediate problem, let's just add an extra call to rq_qos_exit() in blkcg_exit_disk(). This is safe because duplicate calls to rq_qos_exit() become noop's. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: darklight2357@icloud.com Cc: Josef Bacik <josef@toxicpanda.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Fixes: d70675121546 ("block: introduce blk-iolatency io controller") Cc: stable@vger.kernel.org # v4.19+ Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/Y5TQ5gm3O4HXrXR3@slm.duckdns.org Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-14blk-cgroup: properly pin the parent in blkcg_css_onlineChris Mason1-1/+1
blkcg_css_online is supposed to pin the blkcg of the parent, but 397c9f46ee4d refactored things and along the way, changed it to pin the css instead. This results in extra pins, and we end up leaking blkcgs and cgroups. Fixes: 397c9f46ee4d ("blk-cgroup: move blkcg_{pin,unpin}_online out of line") Signed-off-by: Chris Mason <clm@fb.com> Spotted-by: Rik van Riel <riel@surriel.com> Cc: <stable@vger.kernel.org> # v5.19+ Acked-by: Johannes Weiner <hannes@cmpxchg.org> Link: https://lore.kernel.org/r/20221114181930.2093706-1-clm@fb.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: don't update the blkg lookup hint in blkg_conf_prepChristoph Hellwig1-13/+4
blkg_conf_prep just creates a new blkg structure, there is no real need to update the lookup hint which should only be done on a successful lookup in the I/O path. Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220927065425.257876-1-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: pass a gendisk to the blkg allocation helpersChristoph Hellwig1-28/+28
Prepare for storing the blkcg information in the gendisk instead of the request_queue. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-18-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: pass a gendisk to blkcg_schedule_throttleChristoph Hellwig1-3/+5
Pass the gendisk to blkcg_schedule_throttle as part of moving the blk-cgroup infrastructure to be gendisk based. Remove the unused !BLK_CGROUP stub while we're at it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-17-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: pass a gendisk to blkg_destroy_allChristoph Hellwig1-9/+4
Pass the gendisk to blkg_destroy_all as part of moving the blk-cgroup infrastructure to be gendisk based. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-16-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-throttle: pass a gendisk to blk_throtl_init and blk_throtl_exitChristoph Hellwig1-3/+3
Pass the gendisk to blk_throtl_init and blk_throtl_exit as part of moving the blk-cgroup infrastructure to be gendisk based. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-13-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-iolatency: pass a gendisk to blk_iolatency_initChristoph Hellwig1-1/+1
Pass the gendisk to blk_iolatency_init as part of moving the blk-cgroup infrastructure to be gendisk based. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-9-hch@lst.de [axboe: missed inline for blk_iolatency_init() and !CONFIG_BLK_CGROUP_IOLATENCY] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-ioprio: pass a gendisk to blk_ioprio_init and blk_ioprio_exitChristoph Hellwig1-2/+2
Pass the gendisk to blk_ioprio_init and blk_ioprio_exit as part of moving the blk-cgroup infrastructure to be gendisk based. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: pass a gendisk to blkcg_init_queue and blkcg_exit_queueChristoph Hellwig1-20/+5
Pass the gendisk to blkcg_init_disk and blkcg_exit_disk as part of moving the blk-cgroup infrastructure to be gendisk based. Also remove the rather pointless kerneldoc comments for these internal functions with a single caller each. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: remove blkg_lookup_checkChristoph Hellwig1-26/+10
The combinations of an error check with an ERR_PTR return and a lookup with a NULL return leads to ugly handling of the return values in the callers. Just open coding the check and the lookup is much simpler. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: cleanup the blkg_lookup family of functionsChristoph Hellwig1-23/+15
Add a fully inlined blkg_lookup as the extra two checks aren't going to generated a lot more code vs the call to the slowpath routine, and open code the hint update in the two callers that care. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: remove open coded blkg_lookup instancesChristoph Hellwig1-3/+3
Use blkg_lookup instead of open coding it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: remove blk_queue_root_blkgChristoph Hellwig1-2/+1
Just open code it in the only caller and drop the unused !BLK_CGROUP stub. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-09-27blk-cgroup: fix error unwinding in blkcg_init_queueChristoph Hellwig1-6/+7
When blk_throtl_init fails, we need to call blk_ioprio_exit. Switch to proper goto based unwinding to fix this. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Herrmann <aherrmann@suse.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220921180501.1539876-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-13blk-cgroup: Use atomic{,64}_try_cmpxchgUros Bizjak1-1/+1
Use atomic_try_cmpxchg instead of atomic_cmpxchg (*ptr, old, new) == old in blkcg_unuse_delay, blkcg_set_delay and blkcg_clear_delay and atomic64_try_cmpxchg in blkcg_scale_delay. x86 CMPXCHG instruction returns success in ZF flag, so this change saves a compare after cmpxchg (and related move instruction in front of cmpxchg). Also, atomic_try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg fails, enabling further code simplifications. No functional change intended. Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Cc: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20220712154455.66868-1-ubizjak@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-29blk-cgroup: factor out blkcg_free_all_cpd()Jason Yan1-18/+18
To reduce some duplicated code, factor out blkcg_free_all_cpd(). No functional change. Signed-off-by: Jason Yan <yanaijie@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220629070917.3113016-3-yanaijie@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-29blk-cgroup: factor out blkcg_iostat_update()Jason Yan1-17/+20
To reduce some duplicated code, factor out blkcg_iostat_update(). No functional change. Signed-off-by: Jason Yan <yanaijie@huawei.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220629070917.3113016-2-yanaijie@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-27blk-ioprio: Convert from rqos policy to direct callJan Kara1-0/+1
Convert blk-ioprio handling from a rqos policy to a direct call from blk_mq_submit_bio(). Firstly, blk-ioprio is not much of a rqos policy anyway, it just needs a hook in bio submission path to set the bio's IO priority. Secondly, the rqos .track hook gets actually called too late for blk-ioprio purposes and introducing a special rqos hook just for blk-ioprio looks even weirder. Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220623074840.5960-7-jack@suse.cz Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-02block: fix bio_clone_blkg_association() to associate with proper blkcg_gqJan Kara1-6/+2
Commit d92c370a16cb ("block: really clone the block cgroup in bio_clone_blkg_association") changed bio_clone_blkg_association() to just clone bio->bi_blkg reference from source to destination bio. This is however wrong if the source and destination bios are against different block devices because struct blkcg_gq is different for each bdev-blkcg pair. This will result in IOs being accounted (and throttled as a result) multiple times against the same device (src bdev) while throttling of the other device (dst bdev) is ignored. In case of BFQ the inconsistency can even result in crashes in bfq_bic_update_cgroup(). Fix the problem by looking up correct blkcg_gq for the cloned bio. Reported-by: Logan Gunthorpe <logang@deltatee.com> Reported-and-tested-by: Donald Buczek <buczek@molgen.mpg.de> Fixes: d92c370a16cb ("block: really clone the block cgroup in bio_clone_blkg_association") CC: stable@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220602081242.7731-1-jack@suse.cz Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-19blk-cgroup: delete rcu_read_lock_held() WARN_ON_ONCE()Jens Axboe1-1/+0
A previous commit got rid of unnecessary rcu_read_lock() inside the IRQ disabling queue_lock, but this debug statement was left. It's now firing since we are indeed not inside a RCU read lock, but we don't need to be as we're still preempt safe. Get rid of the check, as we have a lockdep assert for holding the queue lock right after it anyway. Link: https://lore.kernel.org/linux-block/46253c48-81cb-0787-20ad-9133afdd9e21@samsung.com/ Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Fixes: 77c570a1ea85 ("blk-cgroup: Remove unnecessary rcu_read_lock/unlock()") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-17blk-cgroup: Remove unnecessary rcu_read_lock/unlock()Fanjun Kong1-3/+1
spin_lock_irq/spin_unlock_irq contains preempt_disable/enable(). Which can serve as RCU read-side critical region, so remove rcu_read_lock/unlock(). Signed-off-by: Fanjun Kong <bh1scw@gmail.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220516173930.159535-1-bh1scw@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-17blk-cgroup: always terminate io.stat linesWolfgang Bumiller1-7/+2
With the removal of seq_get_buf in blkcg_print_one_stat, we cannot make adding the newline conditional on there being relevant stats because the name was already written out unconditionally. Otherwise we may end up with multiple device names in one line which is confusing and doesn't follow the nested-keyed file format. Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com> Fixes: 252c651a4c85 ("blk-cgroup: stop using seq_get_buf") Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220111083159.42340-1-w.bumiller@proxmox.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-02blk-cgroup: cleanup blkcg_maybe_throttle_currentChristoph Hellwig1-7/+1
Use blkcg_css instead of opencoding it. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220420042723.1010598-15-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-02blk-cgroup: cleanup blk_cgroup_congestedChristoph Hellwig1-5/+1
Use blkcg_css instead of open coding it, and switch to a slightly more natural for loop. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220420042723.1010598-14-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-02blk-cgroup: move blkcg_css to blk-cgroup.cChristoph Hellwig1-0/+17
blkcg_css is only used in blk-cgroup.c, so move it there. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220420042723.1010598-13-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-02blk-cgroup: replace bio_blkcg with bio_blkcg_cssChristoph Hellwig1-1/+17
All callers of bio_blkcg actually want the CSS, so replace it with an interface that does return the CSS. This now allows to move struct blkcg_gq to block/blk-cgroup.h instead of exposing it in a public header. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220420042723.1010598-10-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-02blk-cgroup: move struct blkcg to block/blk-cgroup.hChristoph Hellwig1-1/+8
There is no real need to expose the blkcg structure to the whole kernel. Move it to the private header an expose a helper to let the writeback code access the cgwb_list member. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220420042723.1010598-8-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-02blk-cgroup: move blkcg_{pin,unpin}_online out of lineChristoph Hellwig1-23/+65
Move these two functions out of line as there is no good reason to inline them. Also switch to passing a cgroup_subsys_state instead of doing the conversion in the caller to prepare for making the blkcg structure private to blk-cgroup. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220420042723.1010598-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-05-02blk-cgroup: move blk_cgroup_congested out lineChristoph Hellwig1-0/+20
There is no urgent need to inline this function, so move it out of line. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220420042723.1010598-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-04-02Merge tag 'for-5.18/block-2022-04-01' of git://git.kernel.dk/linux-blockLinus Torvalds1-10/+22
Pull block fixes from Jens Axboe: "Either fixes or a few additions that got missed in the initial merge window pull. In detail: - List iterator fix to avoid leaking value post loop (Jakob) - One-off fix in minor count (Christophe) - Fix for a regression in how io priority setting works for an exiting task (Jiri) - Fix a regression in this merge window with blkg_free() being called in an inappropriate context (Ming) - Misc fixes (Ming, Tom)" * tag 'for-5.18/block-2022-04-01' of git://git.kernel.dk/linux-block: blk-wbt: remove wbt_track stub block: use dedicated list iterator variable block: Fix the maximum minor value is blk_alloc_ext_minor() block: restore the old set_task_ioprio() behaviour wrt PF_EXITING block: avoid calling blkg_free() in atomic context lib/sbitmap: allocate sb->map via kvzalloc_node
2022-03-29Merge tag 'ptrace-cleanups-for-v5.18' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull ptrace cleanups from Eric Biederman: "This set of changes removes tracehook.h, moves modification of all of the ptrace fields inside of siglock to remove races, adds a missing permission check to ptrace.c The removal of tracehook.h is quite significant as it has been a major source of confusion in recent years. Much of that confusion was around task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled making the semantics clearer). For people who don't know tracehook.h is a vestiage of an attempt to implement uprobes like functionality that was never fully merged, and was later superseeded by uprobes when uprobes was merged. For many years now we have been removing what tracehook functionaly a little bit at a time. To the point where anything left in tracehook.h was some weird strange thing that was difficult to understand" * tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: ptrace: Remove duplicated include in ptrace.c ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE ptrace: Return the signal to continue with from ptrace_stop ptrace: Move setting/clearing ptrace_message into ptrace_stop tracehook: Remove tracehook.h resume_user_mode: Move to resume_user_mode.h resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume signal: Move set_notify_signal and clear_notify_signal into sched/signal.h task_work: Decouple TIF_NOTIFY_SIGNAL and task_work task_work: Call tracehook_notify_signal from get_signal on all architectures task_work: Introduce task_work_pending task_work: Remove unnecessary include from posix_timers.h ptrace: Remove tracehook_signal_handler ptrace: Remove arch_syscall_{enter,exit}_tracehook ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h ptrace/arm: Rename tracehook_report_syscall report_syscall ptrace: Move ptrace_report_syscall into ptrace.h
2022-03-23block: avoid calling blkg_free() in atomic contextMing Lei1-10/+22
blkg_free() can currently be called in atomic context, either spin lock is held, or run in rcu callback. Meantime either request queue's release handler or ->pd_free_fn can sleep. Fix the issue by scheduling a work function for freeing blkcg_gq the instance. [ 148.553894] BUG: sleeping function called from invalid context at block/blk-sysfs.c:767 [ 148.557381] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/13 [ 148.560741] preempt_count: 101, expected: 0 [ 148.562577] RCU nest depth: 0, expected: 0 [ 148.564379] 1 lock held by swapper/13/0: [ 148.566127] #0: ffffffff82615f80 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire+0x0/0x1b [ 148.569640] Preemption disabled at: [ 148.569642] [<ffffffff8123f9c3>] ___slab_alloc+0x554/0x661 [ 148.573559] CPU: 13 PID: 0 Comm: swapper/13 Kdump: loaded Not tainted 5.17.0_up+ #110 [ 148.576834] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-1.fc33 04/01/2014 [ 148.579768] Call Trace: [ 148.580567] <IRQ> [ 148.581262] dump_stack_lvl+0x56/0x7c [ 148.582367] ? ___slab_alloc+0x554/0x661 [ 148.583526] __might_resched+0x1af/0x1c8 [ 148.584678] blk_release_queue+0x24/0x109 [ 148.585861] kobject_cleanup+0xc9/0xfe [ 148.586979] blkg_free+0x46/0x63 [ 148.587962] rcu_do_batch+0x1c5/0x3db [ 148.589057] rcu_core+0x14a/0x184 [ 148.590065] __do_softirq+0x14d/0x2c7 [ 148.591167] __irq_exit_rcu+0x7a/0xd4 [ 148.592264] sysvec_apic_timer_interrupt+0x82/0xa5 [ 148.593649] </IRQ> [ 148.594354] <TASK> [ 148.595058] asm_sysvec_apic_timer_interrupt+0x12/0x20 Cc: Tejun Heo <tj@kernel.org> Fixes: 0a9a25ca7843 ("block: let blkcg_gq grab request queue's refcnt") Reported-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/linux-block/20220322093322.GA27283@lst.de/ Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220323011308.2010380-1-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-18block: let blkcg_gq grab request queue's refcntMing Lei1-0/+5
In the whole lifetime of blkcg_gq instance, ->q will be referred, such as, ->pd_free_fn() is called in blkg_free, and throtl_pd_free() still may touch the request queue via &tg->service_queue.pending_timer which is handled by throtl_pending_timer_fn(), so it is reasonable to grab request queue's refcnt by blkcg_gq instance. Previously blkcg_exit_queue() is called from blk_release_queue, and it is hard to avoid the use-after-free. But recently commit 1059699f87eb ("block: move blkcg initialization/destroy into disk allocation/release handler") is merged to for-5.18/block, it becomes simple to fix the issue by simply grabbing request queue's refcnt. Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220318130144.1066064-3-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-11resume_user_mode: Move to resume_user_mode.hEric W. Biederman1-1/+1
Move set_notify_resume and tracehook_notify_resume into resume_user_mode.h. While doing that rename tracehook_notify_resume to resume_user_mode_work. Update all of the places that included tracehook.h for these functions to include resume_user_mode.h instead. Update all of the callers of tracehook_notify_resume to call resume_user_mode_work. Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20220309162454.123006-12-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2022-02-16blk-cgroup: set blkg iostat after percpu stat aggregationChengming Zhou1-5/+5
Don't need to do blkg_iostat_set for top blkg iostat on each CPU, so move it after percpu stat aggregation. Fixes: ef45fe470e1e ("blk-cgroup: show global disk stats in root cgroup io.stat") Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20220213085902.88884-1-zhouchengming@bytedance.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-11block: partition include/linux/blk-cgroup.hMing Lei1-1/+1
Partition include/linux/blk-cgroup.h into two parts: one is public part, the other is block layer private part. Suggested by Christoph Hellwig. Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20220211101149.2368042-4-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-11block: move initialization of q->blkg_list into blkcg_init_queueMing Lei1-0/+2
q->blkg_list is only used by blkcg code, so move it into blkcg_init_queue. Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20220211101149.2368042-3-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02block: remove genhd.hChristoph Hellwig1-1/+0
There is no good reason to keep genhd.h separate from the main blkdev.h header that includes it. So fold the contents of genhd.h into blkdev.h and remove genhd.h entirely. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20220124093913.742411-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: don't include <linux/part_stat.h> in blk.hChristoph Hellwig1-0/+1
Not needed, shift it into the source files that need it instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211123185312.1432157-9-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-19blk-cgroup: fix missing put device in error path from blkg_conf_pref()Yu Kuai1-4/+5
If blk_queue_enter() failed due to queue is dying, the blkdev_put_no_open() is needed because blkcg_conf_open_bdev() succeeded. Fixes: 0c9d338c8443 ("blk-cgroup: synchronize blkg creation against policy deactivation") Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20211102020705.2321858-1-yukuai3@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-25blk-cgroup: synchronize blkg creation against policy deactivationYu Kuai1-0/+10
Our test reports a null pointer dereference: [ 168.534653] ================================================================== [ 168.535614] Disabling lock debugging due to kernel taint [ 168.536346] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 168.537274] #PF: supervisor read access in kernel mode [ 168.537964] #PF: error_code(0x0000) - not-present page [ 168.538667] PGD 0 P4D 0 [ 168.539025] Oops: 0000 [#1] PREEMPT SMP KASAN [ 168.539656] CPU: 13 PID: 759 Comm: bash Tainted: G B 5.15.0-rc2-next-202100 [ 168.540954] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_0738364 [ 168.542736] RIP: 0010:bfq_pd_init+0x88/0x1e0 [ 168.543318] Code: 98 00 00 00 e8 c9 e4 5b ff 4c 8b 65 00 49 8d 7c 24 08 e8 bb e4 5b ff 4d0 [ 168.545803] RSP: 0018:ffff88817095f9c0 EFLAGS: 00010002 [ 168.546497] RAX: 0000000000000001 RBX: ffff888101a1c000 RCX: 0000000000000000 [ 168.547438] RDX: 0000000000000003 RSI: 0000000000000002 RDI: ffff888106553428 [ 168.548402] RBP: ffff888106553400 R08: ffffffff961bcaf4 R09: 0000000000000001 [ 168.549365] R10: ffffffffa2e16c27 R11: fffffbfff45c2d84 R12: 0000000000000000 [ 168.550291] R13: ffff888101a1c098 R14: ffff88810c7a08c8 R15: ffffffffa55541a0 [ 168.551221] FS: 00007fac75227700(0000) GS:ffff88839ba80000(0000) knlGS:0000000000000000 [ 168.552278] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 168.553040] CR2: 0000000000000008 CR3: 0000000165ce7000 CR4: 00000000000006e0 [ 168.554000] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 168.554929] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 168.555888] Call Trace: [ 168.556221] <TASK> [ 168.556510] blkg_create+0x1c0/0x8c0 [ 168.556989] blkg_conf_prep+0x574/0x650 [ 168.557502] ? stack_trace_save+0x99/0xd0 [ 168.558033] ? blkcg_conf_open_bdev+0x1b0/0x1b0 [ 168.558629] tg_set_conf.constprop.0+0xb9/0x280 [ 168.559231] ? kasan_set_track+0x29/0x40 [ 168.559758] ? kasan_set_free_info+0x30/0x60 [ 168.560344] ? tg_set_limit+0xae0/0xae0 [ 168.560853] ? do_sys_openat2+0x33b/0x640 [ 168.561383] ? do_sys_open+0xa2/0x100 [ 168.561877] ? __x64_sys_open+0x4e/0x60 [ 168.562383] ? __kasan_check_write+0x20/0x30 [ 168.562951] ? copyin+0x48/0x70 [ 168.563390] ? _copy_from_iter+0x234/0x9e0 [ 168.563948] tg_set_conf_u64+0x17/0x20 [ 168.564467] cgroup_file_write+0x1ad/0x380 [ 168.565014] ? cgroup_file_poll+0x80/0x80 [ 168.565568] ? __mutex_lock_slowpath+0x30/0x30 [ 168.566165] ? pgd_free+0x100/0x160 [ 168.566649] kernfs_fop_write_iter+0x21d/0x340 [ 168.567246] ? cgroup_file_poll+0x80/0x80 [ 168.567796] new_sync_write+0x29f/0x3c0 [ 168.568314] ? new_sync_read+0x410/0x410 [ 168.568840] ? __handle_mm_fault+0x1c97/0x2d80 [ 168.569425] ? copy_page_range+0x2b10/0x2b10 [ 168.570007] ? _raw_read_lock_bh+0xa0/0xa0 [ 168.570622] vfs_write+0x46e/0x630 [ 168.571091] ksys_write+0xcd/0x1e0 [ 168.571563] ? __x64_sys_read+0x60/0x60 [ 168.572081] ? __kasan_check_write+0x20/0x30 [ 168.572659] ? do_user_addr_fault+0x446/0xff0 [ 168.573264] __x64_sys_write+0x46/0x60 [ 168.573774] do_syscall_64+0x35/0x80 [ 168.574264] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 168.574960] RIP: 0033:0x7fac74915130 [ 168.575456] Code: 73 01 c3 48 8b 0d 58 ed 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 444 [ 168.577969] RSP: 002b:00007ffc3080e288 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 168.578986] RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007fac74915130 [ 168.579937] RDX: 0000000000000009 RSI: 000056007669f080 RDI: 0000000000000001 [ 168.580884] RBP: 000056007669f080 R08: 000000000000000a R09: 00007fac75227700 [ 168.581841] R10: 000056007655c8f0 R11: 0000000000000246 R12: 0000000000000009 [ 168.582796] R13: 0000000000000001 R14: 00007fac74be55e0 R15: 00007fac74be08c0 [ 168.583757] </TASK> [ 168.584063] Modules linked in: [ 168.584494] CR2: 0000000000000008 [ 168.584964] ---[ end trace 2475611ad0f77a1a ]--- This is because blkg_alloc() is called from blkg_conf_prep() without holding 'q->queue_lock', and elevator is exited before blkg_create(): thread 1 thread 2 blkg_conf_prep spin_lock_irq(&q->queue_lock); blkg_lookup_check -> return NULL spin_unlock_irq(&q->queue_lock); blkg_alloc blkcg_policy_enabled -> true pd = ->pd_alloc_fn blkg->pd[i] = pd blk_mq_exit_sched bfq_exit_queue blkcg_deactivate_policy spin_lock_irq(&q->queue_lock); __clear_bit(pol->plid, q->blkcg_pols); spin_unlock_irq(&q->queue_lock); q->elevator = NULL; spin_lock_irq(&q->queue_lock); blkg_create if (blkg->pd[i]) ->pd_init_fn -> q->elevator is NULL spin_unlock_irq(&q->queue_lock); Because blkcg_deactivate_policy() requires queue to be frozen, we can grab q_usage_counter to synchoronize blkg_conf_prep() against blkcg_deactivate_policy(). Fixes: e21b7a0b9887 ("block, bfq: add full hierarchical scheduling and cgroups support") Signed-off-by: Yu Kuai <yukuai3@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20211020014036.2141723-1-yukuai3@huawei.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18block: convert the rest of block to bdev_get_queuePavel Begunkov1-8/+8
Convert bdev->bd_disk->queue to bdev_get_queue(), it's uses a cached queue pointer and so is faster. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/addf6ea988c04213697ba3684c853e4ed7642a39.1634219547.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18block: move blk-throtl fast path inlineJens Axboe1-0/+1
Even if no policies are defined, we spend ~2% of the total IO time checking. Move the fast path inline. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>