linux.git/drivers/nvme/host/core.c, branch v4.5

nvme: fix max_segments integer truncation

2016-03-03T21:43:10+00:00

The block layer uses an unsigned short for max_segments.  The way we
calculate the value for NVMe tends to generate very large 32-bit values,
which after integer truncation may lead to a zero value instead of
the desired outcome.

Signed-off-by: Christoph Hellwig 
Reported-by: Jeff Lien 
Tested-by: Jeff Lien 
Reviewed-by: Keith Busch 
Signed-off-by: Jens Axboe

nvme: set queue limits for the admin queue

2016-03-03T21:42:50+00:00

Factor out a helper to set all the device specific queue limits and apply
them to the admin queue in addition to the I/O queues.  Without this the
command size on the admin queue is arbitrarily low, and the missing
other limitations are just minefields waiting for victims.

Signed-off-by: Christoph Hellwig 
Reported-by: Jeff Lien 
Tested-by: Jeff Lien 
Reviewed-by: Keith Busch 
Signed-off-by: Jens Axboe

NVMe: Fix 0-length integrity payload

2016-03-03T21:42:50+00:00

A user could send a passthrough IO command with a metadata pointer to a
namespace without metadata. With metadata length of 0, kmalloc returns
ZERO_SIZE_PTR. Since that is not NULL, the driver would have set this as
the bio's integrity payload, which causes an access fault on completion.

This patch ignores the users metadata buffer if the namespace format
does not support separate metadata.

Reported-by: Stephen Bates 
Signed-off-by: Keith Busch 
Reviewed-by: Sagi Grimberg 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Johannes Thumshirn 
Signed-off-by: Jens Axboe

NVMe: Don't allow unsupported flags

2016-03-03T21:42:50+00:00

The command flags can change the meaning of other fields in the command
that the driver is not prepared to handle. Specifically, the user could
passthrough an SGL flag, causing the controller to misinterpret the PRP
list the driver created, potentially corrupting memory or data.

Signed-off-by: Keith Busch 
Reviewed-by: Jon Derrick 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Johannes Thumshirn 
Signed-off-by: Jens Axboe

NVMe: Move error handling to failed reset handler

2016-03-03T21:42:50+00:00

This moves failed queue handling out of the namespace removal path and
into the reset failure path, fixing a hanging condition if the controller
fails or link down during del_gendisk. Previously the driver had to see
the controller as degraded prior to calling del_gendisk to setup the
queues to fail. But, if the controller happened to fail after this,
there was no task to end outstanding requests.

On failure, all namespace states are set to dead. This has capacity
revalidate to 0, and ends all new requests with error status.

Signed-off-by: Keith Busch 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Johannes Thumshirn 
Signed-off-by: Jens Axboe

NVMe: Fix namespace removal deadlock

2016-03-03T21:42:49+00:00

This patch makes nvme namespace removal lockless. It is up to the caller
to ensure no active namespace scanning is occuring. To ensure no scan
work occurs, the nvme pci driver adds a removing state to the controller
device to avoid queueing scan work during removal. The work is flushed
after setting the state, so no new scan work can be queued.

The lockless removal allows the driver to cleanup a namespace
request_queue if the controller fails during removal. Previously this
could deadlock trying to acquire the namespace mutex in order to handle
such events.

Signed-off-by: Keith Busch 
Reviewed-by: Johannes Thumshirn 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jens Axboe

NVMe: Use IDA for namespace disk naming

2016-03-03T21:42:49+00:00

A namespace may be detached from a controller, but a user may be holding
a reference to it. Attaching a new namespace with the same NSID will create
duplicate names when using the NSID to name the disk.

This patch uses an IDA that is released only when the last reference is
released instead of using the namespace ID.

Signed-off-by: Keith Busch 
Reviewed-by: Sagi Grimberg 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Johannes Thumshirn 
Signed-off-by: Jens Axboe

NVMe: Allow request merges

2016-02-11T20:14:03+00:00

It is generally more efficient to submit larger IO.

Signed-off-by: Keith Busch 
Reviewed-by: Johannes Thumshirn 
Reviewed-by: Sagi Grimberg 
Signed-off-by: Jens Axboe

Merge branch 'for-4.5/nvme' of git://git.kernel.dk/linux-block

2016-01-22T03:58:02+00:00

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
  ...

NVMe: Export NVMe attributes to sysfs group

2016-01-12T22:11:54+00:00

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 
Cc: Sujith Pandel 
Cc: David Milburn 
Signed-off-by: Keith Busch 
Signed-off-by: Jens Axboe