Race conditions are theoretically possible between the NVMe PCI device
removal and the generic PCI bus rescan and device removal that can be
triggered via sysfs.
To avoid those race conditions make the NVMe code use
pci_stop_and_remove_bus_device_locked().
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This is a minor refactor for handling devices that are incapable of IO.
The driver previously used special error codes to know that IO queues
are unavailable, but we have an online queue count now.
This also fixes an issue where the driver successfully sets the queue
count, but either is unable to allocate an IO queue or the device can't
create one for some reason.
If the driver can successfully enable the device and get responses to
admin commands, the driver will bring up a character device for managment
but not create block devices.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Change the behavior of nvme_enable_ctrl to set EN.
Clear CC.SH for both nvme_enable_ctrl and nvme_disable_ctrl.
Remove reading of the CC register and manage the state in
dev->ctrl_config.
Signed-off-by: Dan McLeran <daniel.mcleran@intel.com>
[removed an unwanted write to CC]
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Adds support for devices with max page size smaller than the host's.
In the case we encounter such a host/device combination, the driver will
split a page into as many PRP entries as necessary for the device's page
size capabilities. If the device's reported minimum page size is greater
than the host's, the driver will not attempt to enable the device and
return an error instead.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Submits NVMe asynchronous event requests, one event up to the controller
maximum or number of possible different event types (8), whichever is
smaller. Events successfully returned by the controller are logged.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Use the zeroing function instead of dma_alloc_coherent & memset(,0,)
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Clear QUEUE_FLAG_ADD_RANDOM in all block drivers that set
QUEUE_FLAG_NONROT.
Historically, all block devices have automatically made entropy
contributions. But as previously stated in commit e2e1a148 ("block: add
sysfs knob for turning off disk entropy contributions"):
- On SSD disks, the completion times aren't as random as they
are for rotational drives. So it's questionable whether they
should contribute to the random pool in the first place.
- Calling add_disk_randomness() has a lot of overhead.
There are more reliable sources for randomness than non-rotational block
devices. From a security perspective it is better to err on the side of
caution than to allow entropy contributions from unreliable "random"
sources.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
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
...
There is a potential dead lock if a cpu event occurs during nvme probe
since it registered with hot cpu notification. This fixes the race by
having the module register with notification outside of probe rather
than have each device register.
The actual work is done in a scheduled work queue instead of in the
notifier since assigning IO queues has the potential to block if the
driver creates additional queues.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
It's positively immoral to have a global variable called 'io_timeout'.
Keep the module parameter called io_timeout, though.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Recently, a new sysfs control "iostats" was added to selectively
enable or disable io statistics collection for request queues. This
patch hooks that control.
IO statistics collection is rather expensive on large, multi-node
machines with drives pushing millions of iops. Having the ability to
disable collection if not needed can improve throughput significantly.
As a data point, on a quad E5-4640, I see more than 50% throughput
improvement when io statistics accounting is disabled during heavily
multi-threaded small block random read benchmarks where device
performance is in the million iops+ range.
Signed-off-by: Sam Bradshaw <sbradshaw@micron.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
The routines to get and lock nvme queues required the caller to "put"
or "unlock" them even if getting one returned NULL. This patch fixes that.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
This was originally set to 4 times the IO timeout, but that was when
the IO timeout was 5 seconds instead of 30. 20 seconds for total time
to failure seemed more reasonable than 2 minutes for most, but other
users have requested to make this a module parameter instead.
Signed-off-by: Keith Busch <keith.busch@intel.com>
[renamed the module parameter to retry_time]
[made retry_time static]
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
kmalloc() used by the nvme_alloc_iod() to allocate memory for 'iod'
can fail. So check the return value.
Signed-off-by: Santosh Y <santosh.sy@samsung.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Quiesce and shutdown the device prior to reset, then restart the device and
resume IO after.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Since _nvme_check_size() wasn't being called from anywhere, the compiler
was optimising it away ... along with all the link-time build failures
that would result if any of the structures were the wrong size. Call it
from nvme_exit() for no particular reason.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
It is possible a filesystem may send a flush flagged bio with write
data. There is no such composite NVMe command, so the driver sends flush
and write separately.
The device is allowed to execute these commands in any order, so it was
possible the driver ends the bio after the write completes, but while the
flush is still active. We don't want to let a filesystem believe flush
succeeded before it really has; this could cause data corruption on a
power loss between these events. To fix, this patch splits the flush
and write into chained bios.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
This configures an nvme request_queue as flush capable if the device
has a volatile write cache present.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Adding tracepoints for bio_complete and block_split into nvme to help
with gathering IO info using blktrace and blkparse.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
If a misbehaving device posts a CQE with a command id < depth but for
one that was never allocated, the command info will have a callback
function set to NULL and we don't want to try invoking that.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Help people diagnose what is going wrong at initialisation time by
printing out which command has gone wrong and what the device returned.
Also fix the error message printed while waiting for reset.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Make the copyright dates accurate and remove the final paragraph that
includes the address of the FSF.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Pull NVMe driver updates from Matthew Wilcox:
"Various updates to the NVMe driver. The most user-visible change is
that drive hotplugging now works and CPU hotplug while an NVMe drive
is installed should also work better"
* git://git.infradead.org/users/willy/linux-nvme:
NVMe: Retry failed commands with non-fatal errors
NVMe: Add getgeo to block ops
NVMe: Start-stop nvme_thread during device add-remove.
NVMe: Make I/O timeout a module parameter
NVMe: CPU hot plug notification
NVMe: per-cpu io queues
NVMe: Replace DEFINE_PCI_DEVICE_TABLE
NVMe: Fix divide-by-zero in nvme_trans_io_get_num_cmds
NVMe: IOCTL path RCU protect queue access
NVMe: RCU protected access to io queues
NVMe: Initialize device reference count earlier
NVMe: Add CONFIG_PM_SLEEP to suspend/resume functions
For commands returned with failed status, queue these for resubmission
and continue retrying them until success or for a limited amount of
time. The final timeout was arbitrarily chosen so requests can't be
retried indefinitely.
Since these are requeued on the nvmeq that submitted the command, the
callbacks have to take an nvmeq instead of an nvme_dev as a parameter
so that we can use the locked queue to append the iod to retry later.
The nvme_iod conviently can be used to track how long we've been trying
to successfully complete an iod request. The nvme_iod also provides the
nvme prp dma mappings, so I had to move a few things around so we can
keep those mappings.
Signed-off-by: Keith Busch <keith.busch@intel.com>
[fixed checkpatch issue with long line]
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Some programs require HDIO_GETGEO work, which requires we implement
getgeo.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Done to ensure nvme_thread is not running when there
are no devices to poll.
Signed-off-by: Dan McLeran <daniel.mcleran@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Increase the default timeout to 30 seconds to match SCSI.
Signed-off-by: Keith Busch <keith.busch@intel.com>
[use byte instead of ushort]
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Registers with hot cpu notification to rebalance, and potentially allocate
additional, io queues.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
The device's IO queues are associated with CPUs, so we can use a per-cpu
variable to map the a qid to a cpu. This provides a convienient way
to optimally assign queues to multiple cpus when the device supports
fewer queues than the host has cpus. The previous implementation may
have assigned these poorly in these situations. This patch addresses
this by sharing queues among cpus that are "close" together and should
have a lower lock contention penalty.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Pull block driver update from Jens Axboe:
"On top of the core pull request, here's the pull request for the
driver related changes for 3.15. It contains:
- Improvements for msi-x registration for block drivers (mtip32xx,
skd, cciss, nvme) from Alexander Gordeev.
- A round of cleanups and improvements for drbd from Andreas
Gruenbacher and Rashika Kheria.
- A round of clanups and improvements for bcache from Kent.
- Removal of sleep_on() and friends in DAC960, ataflop, swim3 from
Arnd Bergmann.
- Bug fix for a bug in the mtip32xx async completion code from Sam
Bradshaw.
- Bug fix for accidentally bouncing IO on 32-bit platforms with
mtip32xx from Felipe Franciosi"
* 'for-3.15/drivers' of git://git.kernel.dk/linux-block: (103 commits)
bcache: remove nested function usage
bcache: Kill bucket->gc_gen
bcache: Kill unused freelist
bcache: Rework btree cache reserve handling
bcache: Kill btree_io_wq
bcache: btree locking rework
bcache: Fix a race when freeing btree nodes
bcache: Add a real GC_MARK_RECLAIMABLE
bcache: Add bch_keylist_init_single()
bcache: Improve priority_stats
bcache: Better alloc tracepoints
bcache: Kill dead cgroup code
bcache: stop moving_gc marking buckets that can't be moved.
bcache: Fix moving_pred()
bcache: Fix moving_gc deadlocking with a foreground write
bcache: Fix discard granularity
bcache: Fix another bug recovering from unclean shutdown
bcache: Fix a bug recovering from unclean shutdown
bcache: Fix a journalling reclaim after recovery bug
bcache: Fix a null ptr deref in journal replay
...
Checkpatch has started warning against using DEFINE_PCI_DEVICE_TABLE,
so replace it. Also update the copyright date and bump the module
version number to 0.9.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
This adds rcu protected access to a queue in the nvme IOCTL path
to fix potential races between a surprise removal and queue usage in
nvme_submit_sync_cmd. The fix holds the rcu_read_lock() here to prevent
the nvme_queue from freeing while this path is executing so it can't
sleep, and so this path will no longer wait for a available command
id should they all be in use at the time a passthrough IOCTL request
is received.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
This adds rcu protected access to nvme_queue to fix a race between a
surprise removal freeing the queue and a thread with open reference on
a NVMe block device using that queue.
The queues do not need to be rcu protected during the initialization or
shutdown parts, so I've added a helper function for raw deferencing
to get around the sparse errors.
There is still a hole in the IOCTL path for the same problem, which is
fixed in a subsequent patch.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
If an NVMe device becomes ready but fails to create IO queues, the driver
creates a character device handle so the device can be managed. The
device reference count needs to be initialized before creating the
character device.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Add CONFIG_PM_SLEEP to suspend/resume functions to fix the following
build warning when CONFIG_PM_SLEEP is not selected. This is because
sleep PM callbacks defined by SIMPLE_DEV_PM_OPS are only used when
the CONFIG_PM_SLEEP is enabled.
drivers/block/nvme-core.c:2541:12: warning: 'nvme_suspend' defined but not used [-Wunused-function]
drivers/block/nvme-core.c:2550:12: warning: 'nvme_resume' defined but not used [-Wunused-function]
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
As result of deprecation of MSI-X/MSI enablement functions
pci_enable_msix() and pci_enable_msi_block() all drivers
using these two interfaces need to be updated to use the
new pci_enable_msi_range() or pci_enable_msi_exact()
and pci_enable_msix_range() or pci_enable_msix_exact()
interfaces.
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-nvme@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
PREPARE_[DELAYED_]WORK() are being phased out. They have few users
and a nasty surprise in terms of reentrancy guarantee as workqueue
considers work items to be different if they don't have the same work
function.
nvme_dev->reset_work is multiplexed with multiple work functions.
Introduce nvme_reset_workfn() which invokes nvme_dev->reset_workfn and
always use it as the work function and update the users to set the
->reset_workfn field instead of overriding the work function using
PREPARE_WORK().
It would probably be best to route this with other related updates
through the workqueue tree.
Compile tested.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: linux-nvme@lists.infradead.org
Pull NVMe driver update from Matthew Wilcox:
"Looks like I missed the merge window ... but these are almost all
bugfixes anyway (the ones that aren't have been baking for months)"
* git://git.infradead.org/users/willy/linux-nvme:
NVMe: Namespace use after free on surprise removal
NVMe: Correct uses of INIT_WORK
NVMe: Include device and queue numbers in interrupt name
NVMe: Add a pci_driver shutdown method
NVMe: Disable admin queue on init failure
NVMe: Dynamically allocate partition numbers
NVMe: Async IO queue deletion
NVMe: Surprise removal handling
NVMe: Abort timed out commands
NVMe: Schedule reset for failed controllers
NVMe: Device resume error handling
NVMe: Cache dev->pci_dev in a local pointer
NVMe: Fix lockdep warnings
NVMe: compat SG_IO ioctl
NVMe: remove deprecated IRQF_DISABLED
NVMe: Avoid shift operation when writing cq head doorbell
An nvme block device may have open references when the device is
removed. New commands may still be sent on the removed device, so we
need to ref count the opens, return errors for new commands, and not
free the namespace and nvme_dev until all references are closed.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
We need to initialise the work_struct when we initialise the rest of the
struct nvme_dev, otherwise we'll hit a lockdep warning when we remove
the device. Use PREPARE_WORK to change the function pointer instead
of INIT_WORK.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
On larger systems with many drives, it may help debugging to know which
queue is tied to which interrupt, just by looking at /proc/interrupts.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
We need to shut down the device cleanly when the system is being shut down.
This was in an earlier patch but was inadvertently lost during a rewrite.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Disable the admin queue if device fails during initialization so the
queue's irq is freed.
Signed-off-by: Keith Busch <keith.busch@intel.com>
[rewritten to use nvme_free_queues]
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Some users need more than 64 partitions per device. Rather than simply
increasing the number of partitions, switch to the dynamic partition
allocation scheme.
This means that minor numbers are not stable across boots, but since major
numbers aren't either, I cannot see this being a significant problem.
Tested-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
This attempts to delete all IO queues at the same time asynchronously on
shutdown. This is necessary for a present device that is not responding;
a shutdown operation previously would take 2 minutes per queue-pair
to timeout before moving on to the next queue, making a device removal
appear to take a very long time or "hung" as reported by users.
In the previous worst case, a removal may be stuck forever until a kill
signal is given if there are more than 32 queue pairs since it would run
out of admin command IDs after over an hour of timed out sync commands
(admin queue depth is 64).
This patch will wait for the admin command timeout for all commands to
complete, so the worst case now for an unresponsive controller is 60
seconds, though that still seems like a long time.
Since this adds another way to take queues offline, some duplicate code
resulted so I moved these into more convienient functions.
Signed-off-by: Keith Busch <keith.busch@intel.com>
[make functions static, correct line length and whitespace issues]
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
This adds checks to see if the nvme pci device was removed. The check
reads the status register for the value of -1, which it should never be
unless the device is no longer present.
If a user performs a surprise removal on an nvme device, the driver will
be notified either by the pci driver remove callback if the platform's
slot is capable of this event, or via reading the device BAR status
register, which will indicate controller failure and trigger a reset.
Either way, the device is not present so all outstanding commands would
timeout. This will not send queue deletion commands to a drive that
isn't present and fail after ioremap, significantly speeding up surprise
removal; previously this took over 2 minutes per IO queue pair created,
but this will complete removing the device within a few seconds.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Send nvme abort command to io requests that have timed out on an
initialized device. If the command is not returned after another timeout,
schedule the controller for reset.
Signed-off-by: Keith Busch <keith.busch@intel.com>
[fix endianness issues]
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Schedules a controller reset when it indicates it has a failed status. If
the device does not become ready after a reset, the pci device will be
scheduled for removal.
Signed-off-by: Keith Busch <keith.busch@intel.com>
[fixed checkpatch issue]
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Adds controller error handling on resume power management. If the device
fails to initialize, the device is queued for a reset. If the reset fails,
a thread is spawned to remove the pci device.
If the device resumes as "busy", the device is responding to admin
commands but will not create IO queues. In this case, we need to remove
the gendisks and free the IO queues since they can't be used and may be
holding bios in their lists.
From testing, the dma pools require a pci device so this had to change
the pci driver 'remove' to release the dma resources in line with that
call instead of after all references to the device are released.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
