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2014-07-14block: provide compat ioctl for BLKZEROOUTMikulas Patocka1-0/+1
This patch provides the compat BLKZEROOUT ioctl. The argument is a pointer to two uint64_t values, so there is no need to translate it. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org # 3.7+ Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-07-12blkcg: don't call into policy draining if root_blkg is already goneTejun Heo1-0/+7
While a queue is being destroyed, all the blkgs are destroyed and its ->root_blkg pointer is set to NULL. If someone else starts to drain while the queue is in this state, the following oops happens. NULL pointer dereference at 0000000000000028 IP: [<ffffffff8144e944>] blk_throtl_drain+0x84/0x230 PGD e4a1067 PUD b773067 PMD 0 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: cfq_iosched(-) [last unloaded: cfq_iosched] CPU: 1 PID: 537 Comm: bash Not tainted 3.16.0-rc3-work+ #2 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 task: ffff88000e222250 ti: ffff88000efd4000 task.ti: ffff88000efd4000 RIP: 0010:[<ffffffff8144e944>] [<ffffffff8144e944>] blk_throtl_drain+0x84/0x230 RSP: 0018:ffff88000efd7bf0 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff880015091450 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff88000efd7c10 R08: 0000000000000000 R09: 0000000000000001 R10: ffff88000e222250 R11: 0000000000000000 R12: ffff880015091450 R13: ffff880015092e00 R14: ffff880015091d70 R15: ffff88001508fc28 FS: 00007f1332650740(0000) GS:ffff88001fa80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000028 CR3: 0000000009446000 CR4: 00000000000006e0 Stack: ffffffff8144e8f6 ffff880015091450 0000000000000000 ffff880015091d80 ffff88000efd7c28 ffffffff8144ae2f ffff880015091450 ffff88000efd7c58 ffffffff81427641 ffff880015091450 ffffffff82401f00 ffff880015091450 Call Trace: [<ffffffff8144ae2f>] blkcg_drain_queue+0x1f/0x60 [<ffffffff81427641>] __blk_drain_queue+0x71/0x180 [<ffffffff81429b3e>] blk_queue_bypass_start+0x6e/0xb0 [<ffffffff814498b8>] blkcg_deactivate_policy+0x38/0x120 [<ffffffff8144ec44>] blk_throtl_exit+0x34/0x50 [<ffffffff8144aea5>] blkcg_exit_queue+0x35/0x40 [<ffffffff8142d476>] blk_release_queue+0x26/0xd0 [<ffffffff81454968>] kobject_cleanup+0x38/0x70 [<ffffffff81454848>] kobject_put+0x28/0x60 [<ffffffff81427505>] blk_put_queue+0x15/0x20 [<ffffffff817d07bb>] scsi_device_dev_release_usercontext+0x16b/0x1c0 [<ffffffff810bc339>] execute_in_process_context+0x89/0xa0 [<ffffffff817d064c>] scsi_device_dev_release+0x1c/0x20 [<ffffffff817930e2>] device_release+0x32/0xa0 [<ffffffff81454968>] kobject_cleanup+0x38/0x70 [<ffffffff81454848>] kobject_put+0x28/0x60 [<ffffffff817934d7>] put_device+0x17/0x20 [<ffffffff817d11b9>] __scsi_remove_device+0xa9/0xe0 [<ffffffff817d121b>] scsi_remove_device+0x2b/0x40 [<ffffffff817d1257>] sdev_store_delete+0x27/0x30 [<ffffffff81792ca8>] dev_attr_store+0x18/0x30 [<ffffffff8126f75e>] sysfs_kf_write+0x3e/0x50 [<ffffffff8126ea87>] kernfs_fop_write+0xe7/0x170 [<ffffffff811f5e9f>] vfs_write+0xaf/0x1d0 [<ffffffff811f69bd>] SyS_write+0x4d/0xc0 [<ffffffff81d24692>] system_call_fastpath+0x16/0x1b 776687bce42b ("block, blk-mq: draining can't be skipped even if bypass_depth was non-zero") made it easier to trigger this bug by making blk_queue_bypass_start() drain even when it loses the first bypass test to blk_cleanup_queue(); however, the bug has always been there even before the commit as blk_queue_bypass_start() could race against queue destruction, win the initial bypass test but perform the actual draining after blk_cleanup_queue() already destroyed all blkgs. Fix it by skippping calling into policy draining if all the blkgs are already gone. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Shirish Pargaonkar <spargaonkar@suse.com> Reported-by: Sasha Levin <sasha.levin@oracle.com> Reported-by: Jet Chen <jet.chen@intel.com> Cc: stable@vger.kernel.org Tested-by: Shirish Pargaonkar <spargaonkar@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-07-08block: don't assume last put of shared tags is for the hostChristoph Hellwig1-26/+7
There is no inherent reason why the last put of a tag structure must be the one for the Scsi_Host, as device model objects can be held for arbitrary periods. Merge blk_free_tags and __blk_free_tags into a single funtion that just release a references and get rid of the BUG() when the host reference wasn't the last. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: stable@kernel.org Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-27Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds6-20/+32
Pull block fixes from Jens Axboe: "A small collection of fixes/changes for the current series. This contains: - Removal of dead code from Gu Zheng. - Revert of two bad fixes that went in earlier in this round, marking things as __init that were not purely used from init. - A fix for blk_mq_start_hw_queue() using the __blk_mq_run_hw_queue(), which could place us wrongly. Make it use the non __ variant, which handles cases where we are called from the wrong CPU set. From me. - A fix for drbd, which allocates discard requests without room for the SCSI payload. From Lars Ellenberg. - A fix for user-after-free in the blkcg code from Tejun. - Addition of limiting gaps in SG lists, if the hardware needs it. This is the last pre-req patch for blk-mq to enable the full NVMe conversion. Could wait until 3.17, but it's simple enough so would be nice to have everything we need for the NVMe port in the 3.17 release. From me" * 'for-linus' of git://git.kernel.dk/linux-block: drbd: fix NULL pointer deref in blk_add_request_payload blk-mq: blk_mq_start_hw_queue() should use blk_mq_run_hw_queue() block: add support for limiting gaps in SG lists bio: remove unused macro bip_vec_idx() Revert "block: add __init to elv_register" Revert "block: add __init to blkcg_policy_register" blkcg: fix use-after-free in __blkg_release_rcu() by making blkcg_gq refcnt an atomic_t floppy: format block0 read error message properly
2014-06-25blk-mq: blk_mq_start_hw_queue() should use blk_mq_run_hw_queue()Jens Axboe1-1/+1
Currently it calls __blk_mq_run_hw_queue(), which depends on the CPU placement being correct. This means it's not possible to call blk_mq_start_hw_queues(q) from a context that is correct for all queues, leading to triggering the WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)); in __blk_mq_run_hw_queue(). Reported-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-25block: add support for limiting gaps in SG listsJens Axboe2-0/+18
Another restriction inherited for NVMe - those devices don't support SG lists that have "gaps" in them. Gaps refers to cases where the previous SG entry doesn't end on a page boundary. For NVMe, all SG entries must start at offset 0 (except the first) and end on a page boundary (except the last). Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-23Revert "block: add __init to elv_register"Jens Axboe1-1/+1
This reverts commit b5097e956a4d2919ee248d6481e4204c5568ed5c. The original commit is buggy, we do use the registration functions at runtime, for instance when loading IO schedulers through sysfs. Reported-by: Damien Wyart <damien.wyart@gmail.com>
2014-06-23Revert "block: add __init to blkcg_policy_register"Jens Axboe2-3/+3
This reverts commit a2d445d440003f2d70ee4cd4970ea82ace616fee. The original commit is buggy, we do use the registration functions at runtime for modular builds.
2014-06-23blkcg: fix use-after-free in __blkg_release_rcu() by making blkcg_gq refcnt ↵Tejun Heo2-15/+9
an atomic_t Hello, So, this patch should do. Joe, Vivek, can one of you guys please verify that the oops goes away with this patch? Jens, the original thread can be read at http://thread.gmane.org/gmane.linux.kernel/1720729 The fix converts blkg->refcnt from int to atomic_t. It does some overhead but it should be minute compared to everything else which is going on and the involved cacheline bouncing, so I think it's highly unlikely to cause any noticeable difference. Also, the refcnt in question should be converted to a perpcu_ref for blk-mq anyway, so the atomic_t is likely to go away pretty soon anyway. Thanks. ------- 8< ------- __blkg_release_rcu() may be invoked after the associated request_queue is released with a RCU grace period inbetween. As such, the function and callbacks invoked from it must not dereference the associated request_queue. This is clearly indicated in the comment above the function. Unfortunately, while trying to fix a different issue, 2a4fd070ee85 ("blkcg: move bulk of blkcg_gq release operations to the RCU callback") ignored this and added [un]locking of @blkg->q->queue_lock to __blkg_release_rcu(). This of course can cause oops as the request_queue may be long gone by the time this code gets executed. general protection fault: 0000 [#1] SMP CPU: 21 PID: 30 Comm: rcuos/21 Not tainted 3.15.0 #1 Hardware name: Stratus ftServer 6400/G7LAZ, BIOS BIOS Version 6.3:57 12/25/2013 task: ffff880854021de0 ti: ffff88085403c000 task.ti: ffff88085403c000 RIP: 0010:[<ffffffff8162e9e5>] [<ffffffff8162e9e5>] _raw_spin_lock_irq+0x15/0x60 RSP: 0018:ffff88085403fdf0 EFLAGS: 00010086 RAX: 0000000000020000 RBX: 0000000000000010 RCX: 0000000000000000 RDX: 000060ef80008248 RSI: 0000000000000286 RDI: 6b6b6b6b6b6b6b6b RBP: ffff88085403fdf0 R08: 0000000000000286 R09: 0000000000009f39 R10: 0000000000020001 R11: 0000000000020001 R12: ffff88103c17a130 R13: ffff88103c17a080 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88107fca0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000006e5ab8 CR3: 000000000193d000 CR4: 00000000000407e0 Stack: ffff88085403fe18 ffffffff812cbfc2 ffff88103c17a130 0000000000000000 ffff88103c17a130 ffff88085403fec0 ffffffff810d1d28 ffff880854021de0 ffff880854021de0 ffff88107fcaec58 ffff88085403fe80 ffff88107fcaec30 Call Trace: [<ffffffff812cbfc2>] __blkg_release_rcu+0x72/0x150 [<ffffffff810d1d28>] rcu_nocb_kthread+0x1e8/0x300 [<ffffffff81091d81>] kthread+0xe1/0x100 [<ffffffff8163813c>] ret_from_fork+0x7c/0xb0 Code: ff 47 04 48 8b 7d 08 be 00 02 00 00 e8 55 48 a4 ff 5d c3 0f 1f 00 66 66 66 66 90 55 48 89 e5 +fa 66 66 90 66 66 90 b8 00 00 02 00 <f0> 0f c1 07 89 c2 c1 ea 10 66 39 c2 75 02 5d c3 83 e2 fe 0f +b7 RIP [<ffffffff8162e9e5>] _raw_spin_lock_irq+0x15/0x60 RSP <ffff88085403fdf0> The request_queue locking was added because blkcg_gq->refcnt is an int protected with the queue lock and __blkg_release_rcu() needs to put the parent. Let's fix it by making blkcg_gq->refcnt an atomic_t and dropping queue locking in the function. Given the general heavy weight of the current request_queue and blkcg operations, this is unlikely to cause any noticeable overhead. Moreover, blkcg_gq->refcnt is likely to be converted to percpu_ref in the near future, so whatever (most likely negligible) overhead it may add is temporary. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Link: http://lkml.kernel.org/g/alpine.DEB.2.02.1406081816540.17948@jlaw-desktop.mno.stratus.com Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-20Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds7-91/+43
Pull block fixes from Jens Axboe: "A smaller collection of fixes for the block core that would be nice to have in -rc2. This pull request contains: - Fixes for races in the wait/wakeup logic used in blk-mq from Alexander. No issues have been observed, but it is definitely a bit flakey currently. Alternatively, we may drop the cyclic wakeups going forward, but that needs more testing. - Some cleanups from Christoph. - Fix for an oops in null_blk if queue_mode=1 and softirq completions are used. From me. - A fix for a regression caused by the chunk size setting. It inadvertently used max_hw_sectors instead of max_sectors, which is incorrect, and causes hangs on btrfs multi-disk setups (where hw sectors apparently isn't set). From me. - Removal of WQ_POWER_EFFICIENT in the kblockd creation. This was a recent addition as well, but it actually breaks blk-mq which relies on strict scheduling. If the workqueue power_efficient mode is turned on, this breaks blk-mq. From Matias. - null_blk module parameter description fix from Mike" * 'for-linus' of git://git.kernel.dk/linux-block: blk-mq: bitmap tag: fix races in bt_get() function blk-mq: bitmap tag: fix race on blk_mq_bitmap_tags::wake_cnt blk-mq: bitmap tag: fix races on shared ::wake_index fields block: blk_max_size_offset() should check ->max_sectors null_blk: fix softirq completions for queue_mode == 1 blk-mq: merge blk_mq_drain_queue and __blk_mq_drain_queue blk-mq: properly drain stopped queues block: remove WQ_POWER_EFFICIENT from kblockd null_blk: fix name and description of 'queue_mode' module parameter block: remove elv_abort_queue and blk_abort_flushes
2014-06-18blk-mq: bitmap tag: fix races in bt_get() functionAlexander Gordeev1-8/+5
This update fixes few issues in bt_get() function: - list_empty(&wait.task_list) check is not protected; - was_empty check is always true which results in *every* thread entering the loop resets bt_wait_state::wait_cnt counter rather than every bt->wake_cnt'th thread; - 'bt_wait_state::wait_cnt' counter update is redundant, since it also gets reset in bt_clear_tag() function; Cc: Christoph Hellwig <hch@infradead.org> Cc: Ming Lei <tom.leiming@gmail.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-18blk-mq: bitmap tag: fix race on blk_mq_bitmap_tags::wake_cntAlexander Gordeev1-2/+12
This piece of code in bt_clear_tag() function is racy: bs = bt_wake_ptr(bt); if (bs && atomic_dec_and_test(&bs->wait_cnt)) { atomic_set(&bs->wait_cnt, bt->wake_cnt); wake_up(&bs->wait); } Since nothing prevents bt_wake_ptr() from returning the very same 'bs' address on multiple CPUs, the following scenario is possible: CPU1 CPU2 ---- ---- 0. bs = bt_wake_ptr(bt); bs = bt_wake_ptr(bt); 1. atomic_dec_and_test(&bs->wait_cnt) 2. atomic_dec_and_test(&bs->wait_cnt) 3. atomic_set(&bs->wait_cnt, bt->wake_cnt); If the decrement in [1] yields zero then for some amount of time the decrement in [2] results in a negative/overflow value, which is not expected. The follow-up assignment in [3] overwrites the invalid value with the batch value (and likely prevents the issue from being severe) which is still incorrect and should be a lesser. Cc: Ming Lei <tom.leiming@gmail.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-18blk-mq: bitmap tag: fix races on shared ::wake_index fieldsAlexander Gordeev2-12/+22
Fix racy updates of shared blk_mq_bitmap_tags::wake_index and blk_mq_hw_ctx::wake_index fields. Cc: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Alexander Gordeev <agordeev@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-16Merge git://git.infradead.org/users/willy/linux-nvmeLinus Torvalds1-0/+1
Pull NVMe update from Matthew Wilcox: "Mostly bugfixes again for the NVMe driver. I'd like to call out the exported tracepoint in the block layer; I believe Keith has cleared this with Jens. We've had a few reports from people who're really pounding on NVMe devices at scale, hence the timeout changes (and new module parameters), hotplug cpu deadlock, tracepoints, and minor performance tweaks" [ Jens hadn't seen that tracepoint thing, but is ok with it - it will end up going away when mq conversion happens ] * git://git.infradead.org/users/willy/linux-nvme: (22 commits) NVMe: Fix START_STOP_UNIT Scsi->NVMe translation. NVMe: Use Log Page constants in SCSI emulation NVMe: Define Log Page constants NVMe: Fix hot cpu notification dead lock NVMe: Rename io_timeout to nvme_io_timeout NVMe: Use last bytes of f/w rev SCSI Inquiry NVMe: Adhere to request queue block accounting enable/disable NVMe: Fix nvme get/put queue semantics NVMe: Delete NVME_GET_FEAT_TEMP_THRESH NVMe: Make admin timeout a module parameter NVMe: Make iod bio timeout a parameter NVMe: Prevent possible NULL pointer dereference NVMe: Fix the buffer size passed in GetLogPage(CDW10.NUMD) NVMe: Update data structures for NVMe 1.2 NVMe: Enable BUILD_BUG_ON checks NVMe: Update namespace and controller identify structures to the 1.1a spec NVMe: Flush with data support NVMe: Configure support for block flush NVMe: Add tracepoints NVMe: Protect against badly formatted CQEs ...
2014-06-13blk-mq: merge blk_mq_drain_queue and __blk_mq_drain_queueChristoph Hellwig1-7/+2
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-13blk-mq: properly drain stopped queuesChristoph Hellwig1-1/+1
If we need to drain a queue we need to run all queues, even if they are marked stopped to make sure the driver has a chance to error out on all queued requests. This fixes surprise removal with scsi-mq. Reported-by: Bart Van Assche <bvanassche@acm.org> Tested-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-12block: remove WQ_POWER_EFFICIENT from kblockdMatias Bjørling1-2/+1
blk-mq issues async requests through kblockd. To issue a work request on a specific CPU, kblockd_schedule_delayed_work_on is used. However, the specific CPU choice may not be honored, if the power_efficient option for workqueues is set. blk-mq requires that we have strict per-cpu scheduling, so it wont work properly if kblockd is marked POWER_EFFICIENT and power_efficient is set. Remove the kblockd WQ_POWER_EFFICIENT flag to prevent this behavior. This essentially reverts part of commit 695588f9454b, which added the WQ_POWER_EFFICIENT marker to kblockd. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-12block: remove elv_abort_queue and blk_abort_flushesChristoph Hellwig3-59/+0
elv_abort_queue has no callers, and blk_abort_flushes is only called by elv_abort_queue. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-11Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds10-31/+81
Pull block layer fixes from Jens Axboe: "Final small batch of fixes to be included before -rc1. Some general cleanups in here as well, but some of the blk-mq fixes we need for the NVMe conversion and/or scsi-mq. The pull request contains: - Support for not merging across a specified "chunk size", if set by the driver. Some NVMe devices perform poorly for IO that crosses such a chunk, so we need to support it generically as part of request merging avoid having to do complicated split logic. From me. - Bump max tag depth to 10Ki tags. Some scsi devices have a huge shared tag space. Before we failed with EINVAL if a too large tag depth was specified, now we truncate it and pass back the actual value. From me. - Various blk-mq rq init fixes from me and others. - A fix for enter on a dying queue for blk-mq from Keith. This is needed to prevent oopsing on hot device removal. - Fixup for blk-mq timer addition from Ming Lei. - Small round of performance fixes for mtip32xx from Sam Bradshaw. - Minor stack leak fix from Rickard Strandqvist. - Two __init annotations from Fabian Frederick" * 'for-linus' of git://git.kernel.dk/linux-block: block: add __init to blkcg_policy_register block: add __init to elv_register block: ensure that bio_add_page() always accepts a page for an empty bio blk-mq: add timer in blk_mq_start_request blk-mq: always initialize request->start_time block: blk-exec.c: Cleaning up local variable address returnd mtip32xx: minor performance enhancements blk-mq: ->timeout should be cleared in blk_mq_rq_ctx_init() blk-mq: don't allow queue entering for a dying queue blk-mq: bump max tag depth to 10K tags block: add blk_rq_set_block_pc() block: add notion of a chunk size for request merging
2014-06-10block: add __init to blkcg_policy_registerFabian Frederick2-3/+3
blkcg_policy_register is only called by __init functions: __init cfq_init __init throtl_init Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-10block: add __init to elv_registerFabian Frederick1-1/+1
elv_register is only called by elevator init functions: __init cfq_init __init deadline_init __init noop_init Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-10block: ensure that bio_add_page() always accepts a page for an empty bioJens Axboe2-2/+10
With commit 762380ad9322 added support for chunk sizes and no merging across them, it broke the rule of always allowing adding of a single page to an empty bio. So relax the restriction a bit to allow for that, similarly to what we have always done. This fixes a crash with mkfs.xfs and 512b sector sizes on NVMe. Reported-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-10Merge branch 'for-3.16' of ↵Linus Torvalds5-33/+33
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: "A lot of activities on cgroup side. Heavy restructuring including locking simplification took place to improve the code base and enable implementation of the unified hierarchy, which currently exists behind a __DEVEL__ mount option. The core support is mostly complete but individual controllers need further work. To explain the design and rationales of the the unified hierarchy Documentation/cgroups/unified-hierarchy.txt is added. Another notable change is css (cgroup_subsys_state - what each controller uses to identify and interact with a cgroup) iteration update. This is part of continuing updates on css object lifetime and visibility. cgroup started with reference count draining on removal way back and is now reaching a point where csses behave and are iterated like normal refcnted objects albeit with some complexities to allow distinguishing the state where they're being deleted. The css iteration update isn't taken advantage of yet but is planned to be used to simplify memcg significantly" * 'for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (77 commits) cgroup: disallow disabled controllers on the default hierarchy cgroup: don't destroy the default root cgroup: disallow debug controller on the default hierarchy cgroup: clean up MAINTAINERS entries cgroup: implement css_tryget() device_cgroup: use css_has_online_children() instead of has_children() cgroup: convert cgroup_has_live_children() into css_has_online_children() cgroup: use CSS_ONLINE instead of CGRP_DEAD cgroup: iterate cgroup_subsys_states directly cgroup: introduce CSS_RELEASED and reduce css iteration fallback window cgroup: move cgroup->serial_nr into cgroup_subsys_state cgroup: link all cgroup_subsys_states in their sibling lists cgroup: move cgroup->sibling and ->children into cgroup_subsys_state cgroup: remove cgroup->parent device_cgroup: remove direct access to cgroup->children memcg: update memcg_has_children() to use css_next_child() memcg: remove tasks/children test from mem_cgroup_force_empty() cgroup: remove css_parent() cgroup: skip refcnting on normal root csses and cgrp_dfl_root self css cgroup: use cgroup->self.refcnt for cgroup refcnting ...
2014-06-09blk-mq: add timer in blk_mq_start_requestMing Lei1-16/+1
This way will become consistent with non-mq case, also avoid to update rq->deadline twice for mq. The comment said: "We do this early, to ensure we are on the right CPU.", but no percpu stuff is used in blk_add_timer(), so it isn't necessary. Even when inserting from plug list, there is no such guarantee at all. Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-09blk-mq: always initialize request->start_timeJens Axboe1-3/+2
The blk-mq core only initializes this if io stats are enabled, since blk-mq only reads the field in that case. But drivers could potentially use it internally, so ensure that we always set it to the current time when the request is allocated. Reported-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-09block: blk-exec.c: Cleaning up local variable address returndRickard Strandqvist1-0/+5
Address of local variable assigned to a function parameter This was partly found using a static code analysis program called cppcheck. Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-07mm: convert some level-less printks to pr_*Mitchel Humpherys1-2/+5
printk is meant to be used with an associated log level. There are some instances of printk scattered around the mm code where the log level is missing. Add a log level and adhere to suggestions by scripts/checkpatch.pl by moving to the pr_* macros. Also add the typical pr_fmt definition so that print statements can be easily traced back to the modules where they occur, correlated one with another, etc. This will require the removal of some (now redundant) prefixes on a few print statements. Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06blk-mq: ->timeout should be cleared in blk_mq_rq_ctx_init()Jens Axboe1-0/+2
It'll be used in blk_mq_start_request() to set a potential timeout for the request, so clear it to zero at alloc time to ensure that we know if someone has set it or not. Fixes random early timeouts on NVMe testing. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-06blk-mq: don't allow queue entering for a dying queueKeith Busch1-2/+4
If the queue is going away, don't let new allocs or queueing happen on it. Go through the normal wait process, and exit with ENODEV in that case. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-06blk-mq: bump max tag depth to 10K tagsJens Axboe1-1/+12
For some scsi-mq cases, the tag map can be huge. So increase the max number of tags we support. Additionally, don't fail with EINVAL if a user requests too many tags. Warn that the tag depth has been adjusted down, and store the new value inside the tag_set passed in. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-06block: add blk_rq_set_block_pc()Jens Axboe3-4/+23
With the optimizations around not clearing the full request at alloc time, we are leaving some of the needed init for REQ_TYPE_BLOCK_PC up to the user allocating the request. Add a blk_rq_set_block_pc() that sets the command type to REQ_TYPE_BLOCK_PC, and properly initializes the members associated with this type of request. Update callers to use this function instead of manipulating rq->cmd_type directly. Includes fixes from Christoph Hellwig <hch@lst.de> for my half-assed attempt. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-05block: add notion of a chunk size for request mergingJens Axboe2-1/+20
Some drivers have different limits on what size a request should optimally be, depending on the offset of the request. Similar to dividing a device into chunks. Add a setting that allows the driver to inform the block layer of such a chunk size. The block layer will then prevent merging across the chunks. This is needed to optimally support NVMe with a non-zero stripe size. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-04block: mq flush: clear flush_rq's tag in flush_end_io()Ming Lei1-1/+1
blk_mq_tag_to_rq() needs to be able to tell if it should return the original request, or the flush request if we are doing a flush sequence. Clear the flush tag when IO completes for a flush, since that is what we are comparing against. Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-04blk-mq: let blk_mq_tag_to_rq() take blk_mq_tags as the main parameterJens Axboe1-7/+12
We currently pass in the hardware queue, and get the tags from there. But from scsi-mq, with a shared tag space, it's a lot more convenient to pass in the blk_mq_tags instead as the hardware queue isn't always directly available. So instead of having to re-map to a given hardware queue from rq->mq_ctx, just pass in the tags structure. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-04blk-mq: fix regression from commit 624dbe475416Jens Axboe1-0/+2
When the code was collapsed to avoid duplication, the recent patch for ensuring that a queue is idled before free was dropped, which was added by commit 19c5d84f14d2. Add back the blk_mq_tag_idle(), to ensure we don't leak a reference to an active queue when it is freed. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-04blk-mq: handle NULL req return from blk_map_request in single queue modeJens Axboe1-0/+2
blk_mq_map_request() can return NULL if we fail entering the queue (dying, or removed), in which case it has already ended IO on the bio. So nothing more to do, except just return. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-04blk-mq: fix sparse warning on missed __percpu annotationMing Lei1-1/+1
'struct blk_mq_ctx' is __percpu, so add the annotation and fix the sparse warning reported from Fengguang: [block:for-linus 2/3] block/blk-mq.h:75:16: sparse: incorrect type in initializer (different address spaces) Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-04blk-mq: fix schedule from atomic contextMing Lei4-31/+78
blk_mq_put_ctx() has to be called before io_schedule() in bt_get(). This patch fixes the problem by taking similar approach from percpu_ida allocation for the situation. Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-04blk-mq: move blk_mq_get_ctx/blk_mq_put_ctx to mq private headerMing Lei2-22/+22
The blk-mq tag code need these helpers. Signed-off-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-06-03Merge branch 'locking-core-for-linus' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next Pull core locking updates from Ingo Molnar: "The main changes in this cycle were: - reduced/streamlined smp_mb__*() interface that allows more usecases and makes the existing ones less buggy, especially in rarer architectures - add rwsem implementation comments - bump up lockdep limits" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits) rwsem: Add comments to explain the meaning of the rwsem's count field lockdep: Increase static allocations arch: Mass conversion of smp_mb__*() arch,doc: Convert smp_mb__*() arch,xtensa: Convert smp_mb__*() arch,x86: Convert smp_mb__*() arch,tile: Convert smp_mb__*() arch,sparc: Convert smp_mb__*() arch,sh: Convert smp_mb__*() arch,score: Convert smp_mb__*() arch,s390: Convert smp_mb__*() arch,powerpc: Convert smp_mb__*() arch,parisc: Convert smp_mb__*() arch,openrisc: Convert smp_mb__*() arch,mn10300: Convert smp_mb__*() arch,mips: Convert smp_mb__*() arch,metag: Convert smp_mb__*() arch,m68k: Convert smp_mb__*() arch,m32r: Convert smp_mb__*() arch,ia64: Convert smp_mb__*() ...
2014-06-03Merge branch 'for-3.16/drivers' of git://git.kernel.dk/linux-block into nextLinus Torvalds1-1/+1
Pull block driver changes from Jens Axboe: "Now that the core bits are in, here's the pull request for the driver related changes for 3.16. Nothing out of the ordinary here, mostly business as usual. There are a few pulls of for-3.16/core into this branch, which were done when the blk-mq was modified after the mtip32xx conversion was put in. The pull request contains: - skd and cciss converted to use pci_enable_msix_exact(). From Alexander Gordeev. - A few mtip32xx fixes from Asai @ Micron. - The conversion of mtip32xx from make_request_fn to blk-mq, and a later small fix for that conversion on quiescing for non-queued IO. From me. - A fix for bsg to use an exported function to check whether this driver is request based or not. Needed updating for blk-mq, which is request based, but does not have a request_fn hook. From me. - Small floppy bug fix from Jiri. - A series of cleanups for the cdrom uniform layer from Joe Perches. Gets rid of various old ugly macros, making the code conform more to the modern coding style. - A series of patches for drbd from the drbd crew (Lars Ellenberg and Philipp Reisner). - A use-after-free fix for null_blk from Ming Lei. - Also from Ming Lei is a performance patch for virtio-blk, which can net us a 3x win on kvm platforms where world notification is expensive. - Ming Lei also fixed a stall issue in virtio-blk, due to a race between queue start/stop and resource limits. - A small batch of fixes for xen-blk{back,front} from Olaf Hering and Valentin Priescu" * 'for-3.16/drivers' of git://git.kernel.dk/linux-block: (54 commits) block: virtio_blk: don't hold spin lock during world switch xen-blkback: defer freeing blkif to avoid blocking xenwatch xen blkif.h: fix comment typo in discard-alignment xen/blkback: disable discard feature if requested by toolstack xen-blkfront: remove type check from blkfront_setup_discard floppy: do not corrupt bio.bi_flags when reading block 0 mtip32xx: move error handling to service thread virtio_blk: fix race between start and stop queue mtip32xx: stop block hardware queues before quiescing IO mtip32xx: blk_mq_init_queue() returns an ERR_PTR mtip32xx: convert to use blk-mq cdrom: Remove unnecessary prototype for cdrom_get_disc_info cdrom: Remove unnecessary prototype for cdrom_mrw_exit cdrom: Remove cdrom_count_tracks prototype cdrom: Remove cdrom_get_next_writeable prototype cdrom: Remove cdrom_get_last_written prototype cdrom: Move mmc_ioctls above cdrom_ioctl to remove unnecessary prototype cdrom: Remove unnecessary sanitize_format prototype cdrom: Remove unnecessary check_for_audio_disc prototype cdrom: Remove prototype for open_for_data ...
2014-06-02Merge branch 'for-3.16/core' of git://git.kernel.dk/linux-block into nextLinus Torvalds24-756/+5083
Pull block core updates from Jens Axboe: "It's a big(ish) round this time, lots of development effort has gone into blk-mq in the last 3 months. Generally we're heading to where 3.16 will be a feature complete and performant blk-mq. scsi-mq is progressing nicely and will hopefully be in 3.17. A nvme port is in progress, and the Micron pci-e flash driver, mtip32xx, is converted and will be sent in with the driver pull request for 3.16. This pull request contains: - Lots of prep and support patches for scsi-mq have been integrated. All from Christoph. - API and code cleanups for blk-mq from Christoph. - Lots of good corner case and error handling cleanup fixes for blk-mq from Ming Lei. - A flew of blk-mq updates from me: * Provide strict mappings so that the driver can rely on the CPU to queue mapping. This enables optimizations in the driver. * Provided a bitmap tagging instead of percpu_ida, which never really worked well for blk-mq. percpu_ida relies on the fact that we have a lot more tags available than we really need, it fails miserably for cases where we exhaust (or are close to exhausting) the tag space. * Provide sane support for shared tag maps, as utilized by scsi-mq * Various fixes for IO timeouts. * API cleanups, and lots of perf tweaks and optimizations. - Remove 'buffer' from struct request. This is ancient code, from when requests were always virtually mapped. Kill it, to reclaim some space in struct request. From me. - Remove 'magic' from blk_plug. Since we store these on the stack and since we've never caught any actual bugs with this, lets just get rid of it. From me. - Only call part_in_flight() once for IO completion, as includes two atomic reads. Hopefully we'll get a better implementation soon, as the part IO stats are now one of the more expensive parts of doing IO on blk-mq. From me. - File migration of block code from {mm,fs}/ to block/. This includes bio.c, bio-integrity.c, bounce.c, and ioprio.c. From me, from a discussion on lkml. That should describe the meat of the pull request. Also has various little fixes and cleanups from Dave Jones, Shaohua Li, Duan Jiong, Fengguang Wu, Fabian Frederick, Randy Dunlap, Robert Elliott, and Sam Bradshaw" * 'for-3.16/core' of git://git.kernel.dk/linux-block: (100 commits) blk-mq: push IPI or local end_io decision to __blk_mq_complete_request() blk-mq: remember to start timeout handler for direct queue block: ensure that the timer is always added blk-mq: blk_mq_unregister_hctx() can be static blk-mq: make the sysfs mq/ layout reflect current mappings blk-mq: blk_mq_tag_to_rq should handle flush request block: remove dead code in scsi_ioctl:blk_verify_command blk-mq: request initialization optimizations block: add queue flag for disabling SG merging block: remove 'magic' from struct blk_plug blk-mq: remove alloc_hctx and free_hctx methods blk-mq: add file comments and update copyright notices blk-mq: remove blk_mq_alloc_request_pinned blk-mq: do not use blk_mq_alloc_request_pinned in blk_mq_map_request blk-mq: remove blk_mq_wait_for_tags blk-mq: initialize request in __blk_mq_alloc_request blk-mq: merge blk_mq_alloc_reserved_request into blk_mq_alloc_request blk-mq: add helper to insert requests from irq context blk-mq: remove stale comment for blk_mq_complete_request() blk-mq: allow non-softirq completions ...
2014-05-31blk-mq: push IPI or local end_io decision to __blk_mq_complete_request()Jens Axboe1-7/+13
We have callers outside of the blk-mq proper (like timeouts) that want to call __blk_mq_complete_request(), so rename the function and put the decision code for whether to use ->softirq_done_fn or blk_mq_endio() into __blk_mq_complete_request(). This also makes the interface more logical again. blk_mq_complete_request() attempts to atomically mark the request completed, and calls __blk_mq_complete_request() if successful. __blk_mq_complete_request() then just ends the request. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-05-31blk-mq: remember to start timeout handler for direct queueJens Axboe1-0/+1
Commit 07068d5b8e added a direct-to-hw-queue mode, but this mode needs to remember to add the request timeout handler as well. Without it, we don't track timeouts for these requests. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-05-31block: ensure that the timer is always addedJens Axboe1-1/+1
Commit f793aa537866 relaxed the timer addition a little too much. If the timer isn't pending, we always need to add it. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-05-30blk-mq: blk_mq_unregister_hctx() can be staticFengguang Wu1-2/+2
CC: Jens Axboe <axboe@kernel.dk> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-05-30blk-mq: make the sysfs mq/ layout reflect current mappingsJens Axboe3-19/+93
Currently blk-mq registers all the hardware queues in sysfs, regardless of whether it uses them (e.g. they have CPU mappings) or not. The unused hardware queues lack the cpux/ directories, and the other sysfs entries (like active, pending, etc) are all zeroes. Change this so that sysfs correctly reflects the current mappings of the hardware queues. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-05-30Merge branch 'for-3.16/core' into for-3.16/driversJens Axboe5-37/+45
Pulled in for the blk_mq_tag_to_rq() change, which impacts mtip32xx. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-05-30blk-mq: blk_mq_tag_to_rq should handle flush requestShaohua Li2-4/+12
flush request is special, which borrows the tag from the parent request. Hence blk_mq_tag_to_rq needs special handling to return the flush request from the tag. Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-05-29block: remove dead code in scsi_ioctl:blk_verify_commandDave Jones1-4/+0
filter gets assigned the address of blk_default_cmd_filter on entry to this function, so the !filter condition can never be true. Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>