Currently we use nornal Linux errno values in the block layer, and while
we accept any error a few have overloaded magic meanings.  This patch
instead introduces a new  blk_status_t value that holds block layer specific
status codes and explicitly explains their meaning.  Helpers to convert from
and to the previous special meanings are provided for now, but I suspect
we want to get rid of them in the long run - those drivers that have a
errno input (e.g. networking) usually get errnos that don't know about
the special block layer overloads, and similarly returning them to userspace
will usually return somethings that strictly speaking isn't correct
for file system operations, but that's left as an exercise for later.

For now the set of errors is a very limited set that closely corresponds
to the previous overloaded errno values, but there is some low hanging
fruite to improve it.

blk_status_t (ab)uses the sparse __bitwise annotations to allow for sparse
typechecking, so that we can easily catch places passing the wrong values.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

Turn the error paramter into a pointer so that target drivers can change
the value, and make sure only DM_ENDIO_* values are returned from the
methods.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Instead use the special DM_MAPIO_KILL return value to return -EIO just
like we do for the request based path.  Note that dm-log-writes returned
-ENOMEM in a few places, which now becomes -EIO instead.  No consumer
treats -ENOMEM special so this shouldn't be an issue (and it should
use a mempool to start with to make guaranteed progress).

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

This simplifies the code and especially the error passing a bit and
will help with the next patch.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Once we move the block layer to its own status code we'll still want to
propagate the bio_iov_iter_get_pages, so restructure __blkdev_direct_IO
to take ret into account when returning the errno.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

Only read bio->bi_error once in the common path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

A few (but not all) dm targets use a special EWOULDBLOCK error code for
failing REQ_RAHEAD requests that fail due to a lack of available resources.
But no one else knows about this magic code, and lower level drivers also
don't generate it when failing read-ahead requests for similar reasons.

So remove this special casing and ignore all additional error handling for
REQ_RAHEAD - if this was a real underlying error we'd get a normal read
once the real read comes in.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

We will only have sense data if the command executed and got a SCSI
result, so this is pointless.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Instead of reinventing it poorly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

If the nbd server stops receiving packets altogether we will get stuck
waiting for them to receive indefinitely as the tcp buffer will never
empty, which looks like a deadlock.  Fix this by setting the sk send
timeout to our configured timeout, that way if the server really
misbehaves we'll disconnect cleanly instead of waiting forever.

Reported-by: Dan Melnic <dmm@fb.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

gcc points out an unusual indentation:

drivers/block/loop.c: In function 'loop_set_status':
drivers/block/loop.c:1149:3: error: this 'if' clause does not guard... [-Werror=misleading-indentation]
   if (figure_loop_size(lo, info->lo_offset, info->lo_sizelimit,
   ^~
drivers/block/loop.c:1152:4: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
    goto exit;

This was introduced by a new feature that accidentally moved the opening
braces from one condition to another. Adding a second pair of braces
makes it work correctly again and also more readable.

Fixes: f2c6df7d

 ("loop: support 4k physical blocksize")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

When generating bootable VM images certain systems (most notably
s390x) require devices with 4k blocksize. This patch implements
a new flag 'LO_FLAGS_BLOCKSIZE' which will set the physical
blocksize to that of the underlying device, and allow to change
the logical blocksize for up to the physical blocksize.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

Since using scsi_req() is only allowed against request queues for
which struct scsi_request is the first member of their private
request data, refuse to submit SCSI commands against a queue for
which this is not the case.

References: commit 82ed4db4

 ("block: split scsi_request out of struct request")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Cc: Jeff Layton <jlayton@poochiereds.net>
Cc: Omar Sandoval <osandov@fb.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>

The CDROMREADAUDIO ioctl uses SCSI passthrough when the .disk
pointer has been set in struct cdrom_device_info. Hence check
whether SCSI passthrough is supported before submitting a SCSI
command. Note: both the ide-cd and sr drivers set the disk
pointer in struct cdrom_device_info but neither the pcd nor
the gdrom driver sets that pointer.

References: commit 82ed4db4

 ("block: split scsi_request out of struct request")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Omar Sandoval <osandov@fb.com>
Cc: linux-block@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>

Since the pktcdvd driver only supports request queues for which
struct scsi_request is the first member of their private request
data, refuse to register block layer queues for which struct
scsi_request is not the first member of the private data.

References: commit 82ed4db4

 ("block: split scsi_request out of struct request")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Since BSG only supports request queues for which struct scsi_request
is the first member of their private request data, refuse to register
block layer queues for which struct scsi_request is not the first
member of their private data.

References: commit bd1599d9 ("scsi_transport_sas: fix BSG ioctl memory corruption")
References: commit 82ed4db4

 ("block: split scsi_request out of struct request")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

From the context where a SCSI command is submitted it is not always
possible to figure out whether or not the queue the command is
submitted to has struct scsi_request as the first member of its
private data. Hence introduce the flag QUEUE_FLAG_SCSI_PASSTHROUGH.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Don Brace <don.brace@microsemi.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Running a queue causes the block layer to examine the per-CPU and
hw queues but not the requeue list. Hence add a 'kick' operation
that also examines the requeue list.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Eduardo Valentin <eduval@amazon.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Requests that got stuck in a block driver are neither on
blk_mq_ctx.rq_list nor on any hw dispatch queue. Make these
visible in debugfs through the "busy" attribute.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Eduardo Valentin <eduval@amazon.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

When verifying whether or not a blk-mq driver forgot to kick the
requeue list after having requeued a request it is important to
be able to verify the contents of the requeue list. Hence export
that list through debugfs.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Eduardo Valentin <eduval@amazon.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

When analyzing e.g. queue lockups it is important to know whether
or not a request has already been started. Hence also show the
atomic request flags.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Eduardo Valentin <eduval@amazon.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

This fixes the following warning when building with clang:

    block/cfq-iosched.c:970:19: error: unused function 'min_vdisktime'
        [-Werror,-Wunused-function]

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Jens Axboe <axboe@fb.com>

NBD userland client and server have FUA (forced unit access) support
and flags defined. Make NBD kernel module recognize NBD_FLAG_SEND_FUA,
enable FUA on the queue, and forward FUA requests to the server.

Signed-off-by: Shaun McDowell <shaunjmcdowell@gmail.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Because what the per-sw-queue bio merge does is basically same with
scheduler's .bio_merge(), this patch makes per-sw-queue bio merge
as the default .bio_merge if no scheduler is used or io scheduler
doesn't provide .bio_merge().

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Before blk-mq is introduced, I/O is merged to elevator
before being putted into plug queue, but blk-mq changed the
order and makes merging to sw queue basically impossible.
Then it is observed that throughput of sequential I/O is degraded
about 10%~20% on virtio-blk in the test[1] if mq-deadline isn't used.

This patch moves the bio merging per sw queue before plugging,
like what blk_queue_bio() does, and the performance regression is
fixed under this situation.

[1]. test script:
sudo fio --direct=1 --size=128G --bsrange=4k-4k --runtime=40 --numjobs=16 --ioengine=libaio --iodepth=64 --group_reporting=1 --filename=/dev/vdb --name=virtio_blk-test-$RW --rw=$RW --output-format=json

RW=read or write

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Pull XFS fixes from Darrick Wong:
 "A few miscellaneous bug fixes & cleanups:

   - Fix indlen block reservation accounting bug when splitting delalloc
     extent

   - Fix warnings about unused variables that appeared in -rc1.

   - Don't spew errors when bmapping a local format directory

   - Fix an off-by-one error in a delalloc eof assertion

   - Make fsmap only return inode information for CAP_SYS_ADMIN

   - Fix a potential mount time deadlock recovering cow extents

   - Fix unaligned memory access in _btree_visit_blocks

   - Fix various SEEK_HOLE/SEEK_DATA bugs"

* tag 'xfs-4.12-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: Move handling of missing page into one place in xfs_find_get_desired_pgoff()
  xfs: Fix off-by-in in loop termination in xfs_find_get_desired_pgoff()
  xfs: Fix missed holes in SEEK_HOLE implementation
  xfs: fix off-by-one on max nr_pages in xfs_find_get_desired_pgoff()
  xfs: fix unaligned access in xfs_btree_visit_blocks
  xfs: avoid mount-time deadlock in CoW extent recovery
  xfs: only return detailed fsmap info if the caller has CAP_SYS_ADMIN
  xfs: bad assertion for delalloc an extent that start at i_size
  xfs: fix warnings about unused stack variables
  xfs: BMAPX shouldn't barf on inline-format directories
  xfs: fix indlen accounting error on partial delalloc conversion

Pull block fixes from Jens Axboe:
 "A collection of fixes that should go into this series. This contains:

   - A set of NVMe fixes, pulled from Christoph. This includes a set of
     fixes for the fiber channel bits from James Smart, rdma queue depth
     fix from Marta, controller removal fixes from Ming, and some more
     APST quirk updates from Andy.

   - A blk-mq debugfs fix from Bart, fixing a problem with the
     untangling of the sysfs and debugfs blk-mq bits that was added in
     this series.

   - Error code fix in add_partition() from Dan.

   - A small series of fixes for the new blk-throttle code from Shaohua"

* 'for-linus' of git://git.kernel.dk/linux-block: (21 commits)
  blk-mq: Only register debugfs attributes for blk-mq queues
  nvme: Quirk APST on Intel 600P/P3100 devices
  nvme: only setup block integrity if supported by the driver
  nvme: replace is_flags field in nvme_ctrl_ops with a flags field
  nvme-pci: consistencly use ctrl->device for logging
  partitions/msdos: FreeBSD UFS2 file systems are not recognized
  block: fix an error code in add_partition()
  blk-throttle: force user to configure all settings for io.low
  blk-throttle: respect 0 bps/iops settings for io.low
  blk-throttle: output some debug info in trace
  blk-throttle: add hierarchy support for latency target and idle time
  nvme_fc: remove extra controller reference taken on reconnect
  nvme_fc: correct nvme status set on abort
  nvme_fc: set logging level on resets/deletes
  nvme_fc: revise comment on teardown
  nvme_fc: Support ctrl_loss_tmo
  nvme_fc: get rid of local reconnect_delay
  blk-mq: remove blk_mq_abort_requeue_list()
  nvme: avoid to use blk_mq_abort_requeue_list()
  nvme: use blk_mq_start_hw_queues() in nvme_kill_queues()
  ...

Pull PCI fixes from Bjorn Helgaas:

 - fix PCI_ENDPOINT build error (merged for v4.12)

 - fix Switchtec driver (merged for v4.12)

 - fix imx6 config read timeouts, fallout from changing to non-postable
   reads

 - add PM "needs_resume" flag for i915 suspend issue

* tag 'pci-v4.12-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI/PM: Add needs_resume flag to avoid suspend complete optimization
  PCI: imx6: Fix config read timeout handling
  switchtec: Fix minor bug with partition ID register
  switchtec: Use new cdev_device_add() helper function
  PCI: endpoint: Make PCI_ENDPOINT depend on HAS_DMA

Pul ceph fixes from Ilya Dryomov:
 "A bunch of make W=1 and static checker fixups, a RECONNECT_SEQ
  messenger patch from Zheng and Luis' fallocate fix"

* tag 'ceph-for-4.12-rc3' of git://github.com/ceph/ceph-client:
  ceph: check that the new inode size is within limits in ceph_fallocate()
  libceph: cleanup old messages according to reconnect seq
  libceph: NULL deref on crush_decode() error path
  libceph: fix error handling in process_one_ticket()
  libceph: validate blob_struct_v in process_one_ticket()
  libceph: drop version variable from ceph_monmap_decode()
  libceph: make ceph_msg_data_advance() return void
  libceph: use kbasename() and kill ceph_file_part()

Pull MMC fixes from Ulf Hansson:
 "This contains fixes to make the WiFi work again for the ARM64 Hikey
  board.

  Together with a couple of DTS updates for the Hikey board we have also
  extended the mmc pwrseq_simple, to support a new power-off-delay-us DT
  property, as that was required to enable a graceful power off sequence
  for the WiFi chip"

* tag 'mmc-v4.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  arm64: dts: hikey: Fix WiFi support
  arm64: dts: hi6220: Move board data from the dwmmc nodes to hikey dts
  arm64: dts: hikey: Add the SYS_5V and the VDD_3V3 regulators
  arm64: dts: hi6220: Move the fixed_5v_hub regulator to the hikey dts
  arm64: dts: hikey: Add clock for the pmic mfd
  mfd: dts: hi655x: Add clock binding for the pmic
  mmc: pwrseq_simple: Parse DTS for the power-off-delay-us property
  mmc: dt: pwrseq-simple: Invent power-off-delay-us

Pull sound fixes from Takashi Iwai:
 "This contains a few HD-audio device-specific quirks and an endianess
  fix for USB-audio, as well as the update of quirk model list document.
  All fixes are small and trivial.

  The document update could have been postponed, but it's a good thing
  for user and has absolutely zero risk of breakage, so included here"

* tag 'sound-4.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - apply STAC_9200_DELL_M22 quirk for Dell Latitude D430
  ALSA: hda - Update the list of quirk models
  ALSA: hda - Provide dual-codecs model option for a few Realtek codecs
  ALSA: hda - Apply dual-codec quirk for MSI Z270-Gaming mobo
  ALSA: hda - No loopback on ALC299 codec
  ALSA: usb-audio: fix Amanero Combo384 quirk on big-endian hosts

Pull drm fixes from Dave Airlie:
 "Not a whole lot happening here, a set of amdgpu fixes and one core
  deadlock fix, and some misc drivers fixes"

* tag 'drm-fixes-for-v4.12-rc3' of git://people.freedesktop.org/~airlied/linux:
  drm/amdgpu: fix null point error when rmmod amdgpu.
  drm/amd/powerplay: fix a signedness bugs
  drm/amdgpu: fix NULL pointer panic of emit_gds_switch
  drm/radeon: Unbreak HPD handling for r600+
  drm/amd/powerplay/smu7: disable mclk switching for high refresh rates
  drm/amd/powerplay/smu7: add vblank check for mclk switching (v2)
  drm/radeon/ci: disable mclk switching for high refresh rates (v2)
  drm/amdgpu/ci: disable mclk switching for high refresh rates (v2)
  drm/amdgpu: fix fundamental suspend/resume issue
  drm/gma500/psb: Actually use VBT mode when it is found
  drm: Fix deadlock retry loop in page_flip_ioctl
  drm: qxl: Delay entering atomic context during cursor update
  drm/radeon: Fix oops upon driver load on PowerXpress laptops

We need to return an error for any call that asks for MSI / MSI-X
vectors only, so that non-trivial fallback logic can work properly.

Also valid dev->irq and use the "correct" errno value based on feedback
from Linus.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Fixes: aff17164

 ("PCI: Provide sensible IRQ vector alloc/free routines")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Christoph writes:

"A couple of fixes for the next rc on the nvme front. Various FC fixes
from James, controller removal fixes from Ming (including a block layer
patch), a APST related device quirk from Andy, a RDMA fix for small
queue depth device from Marta, as well as fixes for the lack of
metadata support in non-PCIe drivers and the printk logging format from
me."

The code in blk-mq-debugfs.c assumes that it is working on a blk-mq
queue and is not intended to work on a blk-sq queue. Hence only
register blk-mq debugfs attributes for blk-mq queues.

Fixes: commit 9c1051aa

 ("blk-mq: untangle debugfs and sysfs")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

They have known firmware bugs.  A fix is apparently in the works --
once fixed firmware is available, someone from Intel (Hi, Keith!)
can adjust the quirk accordingly.

Cc: stable@vger.kernel.org # v4.11
Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: Mario Limonciello <mario_limonciello@dell.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Currently only the PCIe driver supports metadata, so we should not claim
integrity support for the other drivers.  This prevents nasty crashes
with targets that advertise metadata support on fabrics.

Also use the opportunity to factor out some code into a separate helper
that isn't even compiled if CONFIG_BLK_DEV_INTEGRITY is disabled.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>