linux-stable.git/drivers/nvme, branch v4.6.2

NVMe: Always use MSI/MSI-x interrupts

2016-04-14T20:04:50+00:00

Multiple users have reported device initialization failure due the driver
not receiving legacy PCI interrupts. This is not unique to any particular
controller, but has been observed on multiple platforms.

There have been no issues reported or observed when with message signaled
interrupts, so this patch attempts to use MSI-x during initialization,
falling back to MSI. If that fails, legacy would become the default.

The setup_io_queues error handling had to change as a result: the admin
queue's msix_entry used to be initialized to the legacy IRQ. The case
where nr_io_queues is 0 would fail request_irq when setting up the admin
queue's interrupt since re-enabling MSI-x fails with 0 vectors, leaving
the admin queue's msix_entry invalid. Instead, return success immediately.

Reported-by: Tim Muhlemmer 
Reported-by: Jon Derrick 
Signed-off-by: Keith Busch 
Signed-off-by: Jens Axboe

NVMe: Fix reset/remove race

2016-04-11T16:00:04+00:00

This fixes a scenario where device is present and being reset, but a
request to unbind the driver occurs.

A previous patch series addressing a device failure removal scenario
flushed reset_work after controller disable to unblock reset_work waiting
on a completion that wouldn't occur. This isn't safe as-is. The broken
scenario can potentially be induced with:

  modprobe nvme && modprobe -r nvme

To fix, the reset work is flushed immediately after setting the controller
removing flag, and any subsequent reset will not proceed with controller
initialization if the flag is set.

The controller status must be polled while active, so the watchdog timer
is also left active until the controller is disabled to cleanup requests
that may be stuck during namespace removal.

[Fixes: ff23a2a15a2117245b4599c1352343c8b8fb4c43]
Signed-off-by: Keith Busch 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Johannes Thumshirn 
Reviewed-by: Sagi Grimberg 
Signed-off-by: Jens Axboe

nvme: avoid cqe corruption when update at the same time as read

2016-03-22T16:27:29+00:00

Make sure the CQE phase (validity) is read before the rest of the
structure. The phase bit is the highest address and the CQE
read will happen on most platforms from lower to upper addresses
and will be done by multiple non-atomic loads. If the structure
is updated by PCI during the reads from the processor, the
processor may get a corrupted copy.

The addition of the new nvme_cqe_valid function that verifies
the validity bit also allows refactoring of the other CQE read
sequences.

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

nvme: lightnvm: return ppa completion status

2016-03-19T01:10:38+00:00

PPAs sent to device is separately acknowledge in a 64bit status
variable. The status is stored in DW0 and DW1 of the completion queue
entry. Store this status inside the nvm_rq for further processing.

This can later be used to implement retry techniques for failed writes
and reads.

Reviewed-by: Christoph Hellwig 
Signed-off-by: Matias Bjørling 
Signed-off-by: Jens Axboe

Merge branch 'for-4.6/drivers' of git://git.kernel.dk/linux-block

2016-03-19T00:13:31+00:00

Pull block driver updates from Jens Axboe:
 "This is the block driver pull request for this merge window.  It sits
  on top of for-4.6/core, that was just sent out.

  This contains:

   - A set of fixes for lightnvm.  One from Alan, fixing an overflow,
     and the rest from the usual suspects, Javier and Matias.

   - A set of fixes for nbd from Markus and Dan, and a fixup from Arnd
     for correct usage of the signed 64-bit divider.

   - A set of bug fixes for the Micron mtip32xx, from Asai.

   - A fix for the brd discard handling from Bart.

   - Update the maintainers entry for cciss, since that hardware has
     transferred ownership.

   - Three bug fixes for bcache from Eric Wheeler.

   - Set of fixes for xen-blk{back,front} from Jan and Konrad.

   - Removal of the cpqarray driver.  It has been disabled in Kconfig
     since 2013, and we were initially scheduled to remove it in 3.15.

   - Various updates and fixes for NVMe, with the most important being:

        - Removal of the per-device NVMe thread, replacing that with a
          watchdog timer instead. From Christoph.

        - Exposing the namespace WWID through sysfs, from Keith.

        - Set of cleanups from Ming Lin.

        - Logging the controller device name instead of the underlying
          PCI device name, from Sagi.

        - And a bunch of fixes and optimizations from the usual suspects
          in this area"

* 'for-4.6/drivers' of git://git.kernel.dk/linux-block: (49 commits)
  NVMe: Expose ns wwid through single sysfs entry
  drivers:block: cpqarray clean up
  brd: Fix discard request processing
  cpqarray: remove it from the kernel
  cciss: update MAINTAINERS
  NVMe: Remove unused sq_head read in completion path
  bcache: fix cache_set_flush() NULL pointer dereference on OOM
  bcache: cleaned up error handling around register_cache()
  bcache: fix race of writeback thread starting before complete initialization
  NVMe: Create discard zero quirk white list
  nbd: use correct div_s64 helper
  mtip32xx: remove unneeded variable in mtip_cmd_timeout()
  lightnvm: generalize rrpc ppa calculations
  lightnvm: remove struct nvm_dev->total_blocks
  lightnvm: rename ->nr_pages to ->nr_sects
  lightnvm: update closed list outside of intr context
  xen/blback: Fit the important information of the thread in 17 characters
  lightnvm: fold get bb tbl when using dual/quad plane mode
  lightnvm: fix up nonsensical configure overrun checking
  xen-blkback: advertise indirect segment support earlier
  ...

NVMe: Expose ns wwid through single sysfs entry

2016-03-16T14:46:25+00:00

The method to uniquely identify a namespace depends on the controller's
specification revision level and implemented capabilities. This patch
has the driver figure this out and exports the unique string through a
single 'wwid' attribute so the user doesn't have this burden.

The longest namespace unique identifier is used if available. If not
available, the driver will concat the controller's vendor, serial,
and model with the namespace ID. The specification provides this as a
unique indentifier.

Signed-off-by: Keith Busch 
Reviewed-by: Hannes Reinecke 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Sagi Grimberg 
Signed-off-by: Jens Axboe

NVMe: Remove unused sq_head read in completion path

2016-03-08T22:01:06+00:00

Signed-off-by: Jon Derrick 
Reviewed-by: Sagi Grimberg 
Signed-off-by: Jens Axboe

NVMe: Create discard zero quirk white list

2016-03-08T15:32:40+00:00

The NVMe specification does not require discarded blocks return zeroes on
read, but provides that behavior as a possibility. Some applications more
efficiently use an SSD if reads on discarded blocks were deterministically
zero, based on the "discard_zeroes_data" queue attribute.

There is no specification defined way to determine device behavior on
discarded blocks, so the driver always left the queue setting disabled. We
can only know behavior based on individual device models, so this patch
adds a flag to the NVMe "quirk" list that vendors may set if they know
their controller works that way. The patch also sets the new flag for one
such known device.

Signed-off-by: Keith Busch 
Suggested-by: Artur Paszkiewicz 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Martin K. Petersen 
Reviewed-by: Johannes Thumshirn 
Reviewed-by: Sagi Grimberg 
Signed-off-by: Jens Axboe

lightnvm: fold get bb tbl when using dual/quad plane mode

2016-03-03T21:45:53+00:00

When the media manager runs in dual or quad plane mode, lightnvm
abstracts away plane specific commands. This poses a problem for
get bad block table, as it reports bad blocks per plane, making the
table either two or four times bigger than expected. Fold the bad block
list before returning.

Signed-off-by: Matias Bjørling 
Signed-off-by: Jens Axboe

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