Pull vfs updates from Al Viro:
 "The first vfs pile, with deep apologies for being very late in this
  window.

  Assorted cleanups and fixes, plus a large preparatory part of iov_iter
  work.  There's a lot more of that, but it'll probably go into the next
  merge window - it *does* shape up nicely, removes a lot of
  boilerplate, gets rid of locking inconsistencie between aio_write and
  splice_write and I hope to get Kent's direct-io rewrite merged into
  the same queue, but some of the stuff after this point is having
  (mostly trivial) conflicts with the things already merged into
  mainline and with some I want more testing.

  This one passes LTP and xfstests without regressions, in addition to
  usual beating.  BTW, readahead02 in ltp syscalls testsuite has started
  giving failures since "mm/readahead.c: fix readahead failure for
  memoryless NUMA nodes and limit readahead pages" - might be a false
  positive, might be a real regression..."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  missing bits of "splice: fix racy pipe->buffers uses"
  cifs: fix the race in cifs_writev()
  ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure
  kill generic_file_buffered_write()
  ocfs2_file_aio_write(): switch to generic_perform_write()
  ceph_aio_write(): switch to generic_perform_write()
  xfs_file_buffered_aio_write(): switch to generic_perform_write()
  export generic_perform_write(), start getting rid of generic_file_buffer_write()
  generic_file_direct_write(): get rid of ppos argument
  btrfs_file_aio_write(): get rid of ppos
  kill the 5th argument of generic_file_buffered_write()
  kill the 4th argument of __generic_file_aio_write()
  lustre: don't open-code kernel_recvmsg()
  ocfs2: don't open-code kernel_recvmsg()
  drbd: don't open-code kernel_recvmsg()
  constify blk_rq_map_user_iov() and friends
  lustre: switch to kernel_sendmsg()
  ocfs2: don't open-code kernel_sendmsg()
  take iov_iter stuff to mm/iov_iter.c
  process_vm_access: tidy up a bit
  ...

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 layer fixes from Jens Axboe:
 "A small collection of fixes that should go in before -rc1.  The pull
  request contains:

   - A two patch fix for a regression with block enabled tagging caused
     by a commit in the initial pull request.  One patch is from Martin
     and ensures that SCSI doesn't truncate 64-bit block flags, the
     other one is from me and prevents us from double using struct
     request queuelist for both completion and busy tags.  This caused
     anything from a boot crash for some, to crashes under load.

   - A blk-mq fix for a potential soft stall when hot unplugging CPUs
     with busy IO.

   - percpu_counter fix is listed in here, that caused a suspend issue
     with virtio-blk due to percpu counters having an inconsistent state
     during CPU removal.  Andrew sent this in separately a few days ago,
     but it's here.  JFYI.

   - A few fixes for block integrity from Martin.

   - A ratelimit fix for loop from Mike Galbraith, to avoid spewing too
     much in error cases"

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: fix regression with block enabled tagging
  scsi: Make sure cmd_flags are 64-bit
  block: Ensure we only enable integrity metadata for reads and writes
  block: Fix integrity verification
  block: Fix for_each_bvec()
  drivers/block/loop.c: ratelimit error messages
  blk-mq: fix potential stall during CPU unplug with IO pending
  percpu_counter: fix bad counter state during suspend

Metric tons of high speed spew is not helpful when things go pear shaped.
systemd lost its mind, forgot how to stop services it insists on being
sole manager of, massive printk() flood ensued, box eventually died.

[16206.684000] loop: Write error at byte offset 11412291584, length 4096.
[16206.684000] systemd-journald[1758]: /dev/kmsg buffer overrun, some messages lost.
[16206.684000] loop: Write error at byte offset 13155434496, length 4096.
[16206.684000] loop: Write error at byte offset 13155438592, length 4096.
[16206.684000] loop: Write error at byte offset 13155442688, length 4096.
[16206.684000] loop: Write error at byte offset 13960736768, length 4096.
[16206.684000] loop: Write error at byte offset 14229172224, length 4096.
[16206.684000] systemd-journald[1758]: /dev/kmsg buffer overrun, some messages lost.
[16206.684000] loop: Write error at byte offset 14766043136, length 4096.
[16206.684000] loop: Write error at byte offset 15034478592, length 4096.
[16206.684000] systemd-journald[1758]: /dev/kmsg buffer overrun, some messages lost.

Signed-off-by: Mike Galbraith <bitbucket@online.de>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@fb.com>