Commit Graph

50 Commits

Author SHA1 Message Date
Keith Busch
f3db22feb5 NVMe: Fix hot cpu notification dead lock
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>
2014-06-13 10:43:34 -04:00
Matthew Wilcox
bd67608a61 NVMe: Rename io_timeout to nvme_io_timeout
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>
2014-06-03 23:04:30 -04:00
Keith Busch
53562be74b NVMe: Flush with data support
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>
2014-05-05 10:54:02 -04:00
Keith Busch
a7d2ce2832 NVMe: Configure support for block flush
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>
2014-05-05 10:53:53 -04:00
Matthew Wilcox
8757ad65d3 NVMe: Update copyright headers
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>
2014-05-05 10:41:25 -04:00
Linus Torvalds
3e8072d48b Merge git://git.infradead.org/users/willy/linux-nvme
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
2014-04-11 16:45:59 -07:00
Keith Busch
edd10d3328 NVMe: Retry failed commands with non-fatal errors
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>
2014-04-10 17:11:59 -04:00
Keith Busch
b355084a89 NVMe: Make I/O timeout a module parameter
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>
2014-04-10 17:04:38 -04:00
Keith Busch
33b1e95c90 NVMe: CPU hot plug notification
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>
2014-04-10 17:03:42 -04:00
Keith Busch
42f614201e NVMe: per-cpu io queues
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>
2014-04-10 17:03:15 -04:00
Keith Busch
4f5099af4f NVMe: IOCTL path RCU protect queue access
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>
2014-03-24 08:54:40 -04:00
Keith Busch
5a92e700af NVMe: RCU protected access to io queues
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>
2014-03-24 08:45:57 -04:00
Tejun Heo
9ca9737444 nvme: don't use PREPARE_WORK
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
2014-03-07 10:24:49 -05:00
Keith Busch
c30341dc3c NVMe: Abort timed out commands
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>
2014-01-27 19:27:53 -05:00
Keith Busch
d4b4ff8e28 NVMe: Schedule reset for failed controllers
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>
2014-01-27 19:20:02 -05:00
Keith Busch
9a6b94584d NVMe: Device resume error handling
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>
2013-12-16 15:54:39 -05:00
Keith Busch
320a382746 NVMe: compat SG_IO ioctl
For 32-bit versions of sg3-utils running on a 64-bit system. This is
mostly a copy from the relevent portions of fs/compat_ioctl.c, with
slight modifications for going through block_device_operations.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@linux.intel.com>
[fixed up CONFIG_COMPAT=n build problems]
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2013-12-16 15:49:40 -05:00
Haiyan Hu
b80d5ccca3 NVMe: Avoid shift operation when writing cq head doorbell
Changes the type of dev->db_stride to unsigned and changes the value
stored there to be 1 << the current value. Then there is less
calculation to be done at completion time.

Signed-off-by: Haiyan Hu <huhaiyan@huawei.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2013-11-18 17:10:51 -05:00
Keith Busch
1894d8f16a NVMe: Use normal shutdown
The NVMe spec recommends using the shutdown normal sequence when safely
taking the controller offline instead of hitting CC.EN on the next
start-up to reset the controller. The spec recommends a minimum of 1
second for the shutdown complete. This patch waits 2 seconds to be on
the safe side.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2013-09-03 16:40:32 -04:00
Matthew Wilcox
c3bfe7176c NVMe: Namespace IDs are unsigned
The 'Number of Namespaces' read from the device was being treated as
signed, which would cause us to not scan any namespaces for a device
with more than 2 billion namespaces.  That led to noticing that the
namespace ID was also being treated as signed, which could lead to the
result from NVME_IOCTL_ID being treated as an error code.

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2013-09-03 16:32:26 -04:00
Matthew Wilcox
42c7768316 NVMe: Split header file into user-visible and kernel-visible pieces
To build user programs that call the NVMe ioctls, we need to have a
user header file.  Catch up to the new way of doing that by splitting
the header file into kernel and uapi portions.

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2013-09-03 16:32:25 -04:00
Keith Busch
6198221fa0 NVMe: Disk IO statistics
Add io stats accounting for bio requests so nvme block devices show
useful disk stats.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2013-06-20 12:06:35 -04:00
Matthew Wilcox
ab3ea5bf37 NVMe: Simplify Firmware Activate code slightly
Add definitions for the three Firmware Activate actions, and change the
SCSI translation code to construct the command into a temporary variable
instead of translating the endianness back-and-forth.

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@linux.intel.com>
2013-05-08 09:55:05 -04:00
Keith Busch
f410c680b5 NVMe: Meta-data support in NVME_IOCTL_SUBMIT_IO
This adds support for namespaces with separate meta-data formats in the
submit io ioctl. The meta-data buffer has to be a contiguous, so such
a buffer is allocated and the mapped user pages are copied to/from this
buffer for write/read commands.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2013-05-02 15:35:09 -04:00
Keith Busch
159b67d7ae NVMe: Device specific stripe size handling
We have an nvme device that has a concept of a stripe size. IO requests
that do not transfer data crossing a stripe boundary has greater
performance compared to IO that does cross it. This patch sets the
stripe size for the device if the device and vendor ids match one with
this feature and splits IO requests that cross the stripe boundary.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
2013-05-02 14:41:05 -04:00