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2016-01-21Merge branch 'for-4.5/nvme' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull NVMe updates from Jens Axboe: "Last branch for this series is the nvme changes. It's in a separate branch to avoid splitting too much between core and NVMe changes, since NVMe is still helping drive some blk-mq changes. That said, not a huge amount of core changes in here. The grunt of the work is the continued split of the code" * 'for-4.5/nvme' of git://git.kernel.dk/linux-block: (67 commits) uapi: update install list after nvme.h rename NVMe: Export NVMe attributes to sysfs group NVMe: Shutdown controller only for power-off NVMe: IO queue deletion re-write NVMe: Remove queue freezing on resets NVMe: Use a retryable error code on reset NVMe: Fix admin queue ring wrap nvme: make SG_IO support optional nvme: fixes for NVME_IOCTL_IO_CMD on the char device nvme: synchronize access to ctrl->namespaces nvme: Move nvme_freeze/unfreeze_queues to nvme core PCI/AER: include header file NVMe: Export namespace attributes to sysfs NVMe: Add pci error handlers block: remove REQ_NO_TIMEOUT flag nvme: merge iod and cmd_info nvme: meta_sg doesn't have to be an array nvme: properly free resources for cancelled command nvme: simplify completion handling nvme: special case AEN requests ...
2016-01-21Merge branch 'for-4.5/lightnvm' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull lightnvm fixes and updates from Jens Axboe: "This should have been part of the drivers branch, but it arrived a bit late and wasn't based on the official core block driver branch. So they got a small scolding, but got a pass since it's still new. Hence it's in a separate branch. This is mostly pure fixes, contained to lightnvm/, and minor feature additions" * 'for-4.5/lightnvm' of git://git.kernel.dk/linux-block: (26 commits) lightnvm: ensure that nvm_dev_ops can be used without CONFIG_NVM lightnvm: introduce factory reset lightnvm: use system block for mm initialization lightnvm: introduce ioctl to initialize device lightnvm: core on-disk initialization lightnvm: introduce mlc lower page table mappings lightnvm: add mccap support lightnvm: manage open and closed blocks separately lightnvm: fix missing grown bad block type lightnvm: reference rrpc lun in rrpc block lightnvm: introduce nvm_submit_ppa lightnvm: move rq->error to nvm_rq->error lightnvm: support multiple ppas in nvm_erase_ppa lightnvm: move the pages per block check out of the loop lightnvm: sectors first in ppa list lightnvm: fix locking and mempool in rrpc_lun_gc lightnvm: put block back to gc list on its reclaim fail lightnvm: check bi_error in gc lightnvm: return the get_bb_tbl return value lightnvm: refactor end_io functions for sync ...
2016-01-19Merge branch 'for-4.5/core' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull core block updates from Jens Axboe: "We don't have a lot of core changes this time around, it's mostly in drivers, which will come in a subsequent pull. The cores changes include: - blk-mq - Prep patch from Christoph, changing blk_mq_alloc_request() to take flags instead of just using gfp_t for sleep/nosleep. - Doc patch from me, clarifying the difference between legacy and blk-mq for timer usage. - Fixes from Raghavendra for memory-less numa nodes, and a reuse of CPU masks. - Cleanup from Geliang Tang, using offset_in_page() instead of open coding it. - From Ilya, rename request_queue slab to it reflects what it holds, and a fix for proper use of bdgrab/put. - A real fix for the split across stripe boundaries from Keith. We yanked a broken version of this from 4.4-rc final, this one works. - From Mike Krinkin, emit a trace message when we split. - From Wei Tang, two small cleanups, not explicitly clearing memory that is already cleared" * 'for-4.5/core' of git://git.kernel.dk/linux-block: block: use bd{grab,put}() instead of open-coding block: split bios to max possible length block: add call to split trace point blk-mq: Avoid memoryless numa node encoded in hctx numa_node blk-mq: Reuse hardware context cpumask for tags blk-mq: add a flags parameter to blk_mq_alloc_request Revert "blk-flush: Queue through IO scheduler when flush not required" block: clarify blk_add_timer() use case for blk-mq bio: use offset_in_page macro block: do not initialise statics to 0 or NULL block: do not initialise globals to 0 or NULL block: rename request_queue slab cache
2016-01-12NVMe: Export NVMe attributes to sysfs groupKeith Busch
Adds all controller information to attribute list exposed to sysfs, and appends the reset_controller attribute to it. The nvme device is created with this attribute list, so driver no long manages its attributes. Reported-by: Sujith Pandel <sujithpshankar@gmail.com> Cc: Sujith Pandel <sujithpshankar@ gmail.com> Cc: David Milburn <dmilburn@redhat.com> Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12NVMe: Shutdown controller only for power-offKeith Busch
We don't need to shutdown a controller for a reset. A controller in a shutdown state may take longer to become ready than one that was simply disabled. This patch has the driver shut down a controller only if the device is about to be powered off or being removed. When taking the controller down for a reset reason, the controller will be disabled instead. Function names have been updated in this patch to reflect their changed semantics. Signed-off-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12NVMe: IO queue deletion re-writeKeith Busch
The nvme driver deletes IO queues asynchronously since this operation may potentially take an undesirable amount of time with a large number of queues if done serially. The driver used to manage coordinating asynchronous deletions. This patch simplifies that by leveraging the block layer rather than using kthread workers and chaining more complicated callbacks. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12NVMe: Remove queue freezing on resetsKeith Busch
NVMe submits all commands through the block layer now. This means we can let requests queue at the blk-mq hardware context since there is no path that bypasses this anymore so we don't need to freeze the queues anymore. The driver can simply stop the h/w queues from running during a reset instead. This also fixes a WARN in percpu_ref_reinit when the queue was unfrozen with requeued requests. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12NVMe: Use a retryable error code on resetKeith Busch
A negative status has the "do not retry" bit set, which makes it not retryable. Use a fake status that can potentially be retried on reset. An aborted command's status is overridden by the timeout handler so that it won't be retried, which is necessary to keep initialization from getting into a reset loop. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12NVMe: Fix admin queue ring wrapKeith Busch
The tag set queue depth needs to be one less than the h/w queue depth so we don't wrap the circular buffer. This conforms to the specification defined "Full Queue" condition. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12nvme: make SG_IO support optionalChristoph Hellwig
Translation SCSI commands to NVMe commands is rather pointless in general as applications must not expext to be able to use SCSI commands on a generic block device. Make the huge translation layer optional and hope no one will ever enable it in the future. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12nvme: fixes for NVME_IOCTL_IO_CMD on the char deviceChristoph Hellwig
Make sure we synchronize access to the namespaces list and grab a reference to the namespace before doing I/O. Make sure to reject the ioctl if multiple namespaces are present as it's entirely unsafe, and warn when using it even with a single namespace. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12nvme: synchronize access to ctrl->namespacesChristoph Hellwig
Currently traversal and modification of ctrl->namespaces happens completely unsynchronized, which can be fixed by the addition of a simple mutex. Note: nvme_dev_ioctl will be handled in the next patch. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12nvme: Move nvme_freeze/unfreeze_queues to nvme coreSagi Grimberg
Nothing pci specific about them and We'll need them exported in other transports too. Signed-off-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: introduce mlc lower page table mappingsMatias Bjørling
NAND MLC memories have both lower and upper pages. When programming, both of these must be written, before data can be read. However, these lower and upper pages might not placed at even and odd flash pages, but can be skipped. Therefore each flash memory has its lower pages defined, which can then be used when programming and to know when padding are necessary. This patch implements the lower page definition in the specification, and exposes it through a simple lookup table at dev->lptbl. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: return the get_bb_tbl return valueMatias Bjørling
During get_bb_tbl, a callback is used to allow an user-specific scan function to be called. The callback may return an error, and in that case, the return value is overridden. However, the callback error is needed when the fault is a user error and not a kernel error. For example, when a user tries to initialize the same device twice. The get_bb_tbl callback should be able to communicate this. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: refactor end_io functions for syncMatias Bjørling
To implement sync I/O support within the LightNVM core, the end_io functions are refactored to take an end_io function pointer instead of testing for initialized media manager, followed by calling its end_io function. Sync I/O can then be implemented using a callback that signal I/O completion. This is similar to the logic found in blk_to_execute_io(). By implementing it this way, the underlying device I/Os submission logic is abstracted away from core, targets, and media managers. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22NVMe: IO ending fixes on surprise removalKeith Busch
This patch fixes a lost request discovered during IO + hot removal. The driver's pci removal deletes gendisks prior to shutting down the controller to allow dirty data to sync. Dirty data can not be synced on a surprise removal, though, and would potentially block indefinitely. The driver previously had marked the queue as dying in this scenario to prevent new requests from attempting, however it will still block for requests that already entered the queue. This patch fixes this by quiescing IO first, then aborting the requeued requests before deleting disks. Reported-by: Sujith Pandel <sujith_pandel@dell.com> Signed-off-by: Keith Busch <keith.busch@intel.com> Tested-by: Sujith Pandel <sujith_pandel@dell.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22NVMe: Export namespace attributes to sysfsKeith Busch
Exposes the NGUID, EUI-64, and NSID to sysfs entries under the disk's kobject. Signed-off-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22NVMe: Add pci error handlersKeith Busch
Requests enabling pcie aer support. Shuts down the controller on error detected with io frozen state prior to requesting slot reset; resumes controller after reset completes. Signed-off-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: merge iod and cmd_infoChristoph Hellwig
Merge the two per-request structures in the nvme driver into a single one. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: meta_sg doesn't have to be an arrayChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: properly free resources for cancelled commandChristoph Hellwig
We need to move freeing of resources to the ->complete handler to ensure they are also freed when we cancel the command. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: simplify completion handlingChristoph Hellwig
Now that all commands are executed as block layer requests we can remove the internal completion in the NVMe driver. Note that we can simply call blk_mq_complete_request to abort commands as the block layer will protect against double copletions internally. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: special case AEN requestsChristoph Hellwig
AEN requests are different from other requests in that they don't time out or can easily be cancelled. Because of that we should not use the blk-mq infrastructure but just special case them in the completion path. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: switch abort to blk_execute_rq_nowaitChristoph Hellwig
And remove the now unused nvme_submit_cmd helper. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: switch delete SQ/CQ to blk_execute_rq_nowaitChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: factor out a few helpers from req_completionChristoph Hellwig
We'll need them in other places later. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: fix admin queue depthChristoph Hellwig
The number in tag_set->queue depth includes the reserved tags. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22NVMe: Simplify metadata setupKeith Busch
We no longer require the two-pass setup for block integrity. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22NVMe: Remove device management handles on removeKeith Busch
We don't want to allow new references to open on a device that is removed. This ties the lifetime of these handles to the physical device's presence rather than to the open reference count. Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22NVMe: Use unbounded work queue for all workKeith Busch
Removes all usage of the global work queue so work can't be scheduled on two different work queues, and removes nvme's work queue singlethreadedness so controllers can be driven in parallel. Signed-off-by: Keith Busch <keith.busch@intel.com> [hch: keep the dead controller removal on the system workqueue to avoid deadlocks] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22NVMe: Implement namespace list scanningKeith Busch
The NVMe 1.1 specification provides an identify mode to return a list of active namespaces. This is more efficient to discover which namespace identifiers are active on a controller, providing potentially significant improvement in scan time for controllers with sparesly populated namespaces. Signed-off-by: Keith Busch <keith.busch@intel.com> [hch: add quirk for the broken Qemu Identify implementation. To be relaxed later] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: switch abort_limit to an atomic_tChristoph Hellwig
There is no lock to sychronize access to the abort_limit field of struct nvme_ctrl, so switch it to an atomic_t. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: remove dead controllers from a work itemChristoph Hellwig
Compared to the kthread this gives us multiple call prevention for free. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: merge probe_work and reset_workChristoph Hellwig
If we're using two work queues we're always going to run into races where one item is tearing down what the other one is initializing. So insted merge the two work queues, and let the old probe_work also tear the controller down first if it was alive. Together with the better detection of the probe path using a flag this gives us a properly serialized reset/probe path that also doesn't accidentally trigger when two commands time out and the second one tries to reset the controller while the first reset is still in progress. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: do not restart the request timeout if we're resetting the controllerKeith Busch
Otherwise we're never going to complete a command when it is restarted just after we completed all other outstanding commands in nvme_clear_queue. The controller must be disabled prior to completing a presumed lost command, do this by directly shutting down the controller before queueing the reset work, and return EH_HANDLED from the timeout handler after we shut the controller down. Signed-off-by: Keith Busch <keith.busch@intel.com> [hch: split and rebase] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: simplify resetsChristoph Hellwig
Don't delete the controller from dev_list before queuing a reset, instead just check for it being reset in the polling kthread. This allows to remove the dev_list_lock in various places, and in addition we can simply rely on checking the queue_work return value to see if we could reset a controller. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: add NVME_SC_CANCELLEDChristoph Hellwig
To properly document how we are using a negative Linux error value to communicate request cancellations inside the driver. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: merge nvme_abort_req and nvme_timeoutChristoph Hellwig
We want to be able to return bettern error values frmo nvme_timeout, which is significantly easier if the two functions are merged. Also clean up and reduce the printk spew so that we only get one message per abort. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: don't take the I/O queue q_lock in nvme_timeoutChristoph Hellwig
There is nothing it protects, but it makes lockdep unhappy in many different ways. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: protect against simultaneous shutdown invocationsKeith Busch
Signed-off-by: Keith Busch <keith.busch@intel.com> [hch: split from a larger patch] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: only add a controller to dev_list after it's been fully initializedChristoph Hellwig
Without this we can easily get bad derferences on nvmeq->d_db when the nvme kthread tries to poll the CQs for controllers that are in half initialized state. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22nvme: only ignore hardware errors in nvme_create_io_queuesChristoph Hellwig
Half initialized queues due to kernel error returns or timeout are still a good reason to give up on initializing a controller. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-09nvme: precedence bug in nvme_pr_clear()Dan Carpenter
The "|" operator has higher precedence than "?:" so this didn't work as intended. I had previously fixed this bug, but it we copied the older unfixed version when we moved the function between files. Fixes: 1673f1f08c88 ('nvme: move block_device_operations and ns/ctrl freeing to common code') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-08nvme: fix another 32-bit build warningArnd Bergmann
The nvme_user_cmd function was recently moved around from one file to another, which made a warning reappear that I had fixed before at some point: drivers/nvme/host/core.c: In function 'nvme_user_cmd': drivers/nvme/host/core.c:424:4: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] This applies the same workaround that we have elsewhere in the driver with an extra type cast to uintptr_t. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: 1673f1f08c88 ("nvme: move block_device_operations and ns/ctrl freeing to common code") Link: https://lkml.org/lkml/2015/10/9/611 Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-07lightnvm: replace req queue with nvmdev for lldMatias Bjørling
In the case where a request queue is passed to the low lever lightnvm device drive integration, the device driver might pass its admin commands through another queue. Instead pass nvm_dev, and let the low level drive the appropriate queue. Reported-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-07lightnvm: check mm before useMatias Bjørling
The core can may issue I/Os before a media manager is registered with the lightnvm subsystem. Make sure that we don't call the media manager ->end_io prematurely with a null pointer. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-03NVMe: fix build with CONFIG_NVM enabledChristoph Hellwig
Looks like I didn't test with CONFIG_NVM enabled, and neither did the build bot. Most of this is really weird crazy shit in the lighnvm support, though. Struct nvme_ns is a structure for the NVM I/O command set, and it has no business poking into it. Second this commit: commit 47b3115ae7b799be8b77b0f024215ad4f68d6460 Author: Wenwei Tao <ww.tao0320@gmail.com> Date: Fri Nov 20 13:47:55 2015 +0100 nvme: lightnvm: use admin queues for admin cmds Does even more crazy stuff. If a function gets a request_queue parameter passed it'd better use that and not look for another one. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-03blk-integrity: empty implementation when disabledKeith Busch
This patch moves the blk_integrity_payload definition outside the CONFIG_BLK_DEV_INTERITY dependency and provides empty function implementations when the kernel configuration disables integrity extensions. This simplifies drivers that make use of these to map user data so they don't need to repeat the same configuration checks. Signed-off-by: Keith Busch <keith.busch@intel.com> Updated by Jens to pass an error pointer return from bio_integrity_alloc(), otherwise if CONFIG_BLK_DEV_INTEGRITY isn't set, we return a weird ENOMEM from __nvme_submit_user_cmd() if a meta buffer is set. Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-01nvme: temporary fix for Apple controller resetStephan Günther
Recent patches added basic support for the Apple NVMe controller but still cause resets and data corruption on that particular controller when a specific pattern of read/flush commands occurs. Limiting the queue depth to 2 works around that issue. This patch enforces that limit only for the Apple controller and is considered a temporary fix until we find the root source of that problem. Signed-off-by: Stephan Günther <guenther@tum.de> Signed-off-by: Maurice Leclaire <leclaire@in.tum.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>