<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/fs/block_dev.c, branch v4.15.5</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.15.5</id>
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<updated>2017-11-14T23:32:19Z</updated>
<entry>
<title>Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block</title>
<updated>2017-11-14T23:32:19Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2017-11-14T23:32:19Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=e2c5923c349c1738fe8fda980874d93f6fb2e5b6'/>
<id>urn:sha1:e2c5923c349c1738fe8fda980874d93f6fb2e5b6</id>
<content type='text'>
Pull core block layer updates from Jens Axboe:
 "This is the main pull request for block storage for 4.15-rc1.

  Nothing out of the ordinary in here, and no API changes or anything
  like that. Just various new features for drivers, core changes, etc.
  In particular, this pull request contains:

   - A patch series from Bart, closing the whole on blk/scsi-mq queue
     quescing.

   - A series from Christoph, building towards hidden gendisks (for
     multipath) and ability to move bio chains around.

   - NVMe
        - Support for native multipath for NVMe (Christoph).
        - Userspace notifications for AENs (Keith).
        - Command side-effects support (Keith).
        - SGL support (Chaitanya Kulkarni)
        - FC fixes and improvements (James Smart)
        - Lots of fixes and tweaks (Various)

   - bcache
        - New maintainer (Michael Lyle)
        - Writeback control improvements (Michael)
        - Various fixes (Coly, Elena, Eric, Liang, et al)

   - lightnvm updates, mostly centered around the pblk interface
     (Javier, Hans, and Rakesh).

   - Removal of unused bio/bvec kmap atomic interfaces (me, Christoph)

   - Writeback series that fix the much discussed hundreds of millions
     of sync-all units. This goes all the way, as discussed previously
     (me).

   - Fix for missing wakeup on writeback timer adjustments (Yafang
     Shao).

   - Fix laptop mode on blk-mq (me).

   - {mq,name} tupple lookup for IO schedulers, allowing us to have
     alias names. This means you can use 'deadline' on both !mq and on
     mq (where it's called mq-deadline). (me).

   - blktrace race fix, oopsing on sg load (me).

   - blk-mq optimizations (me).

   - Obscure waitqueue race fix for kyber (Omar).

   - NBD fixes (Josef).

   - Disable writeback throttling by default on bfq, like we do on cfq
     (Luca Miccio).

   - Series from Ming that enable us to treat flush requests on blk-mq
     like any other request. This is a really nice cleanup.

   - Series from Ming that improves merging on blk-mq with schedulers,
     getting us closer to flipping the switch on scsi-mq again.

   - BFQ updates (Paolo).

   - blk-mq atomic flags memory ordering fixes (Peter Z).

   - Loop cgroup support (Shaohua).

   - Lots of minor fixes from lots of different folks, both for core and
     driver code"

* 'for-4.15/block' of git://git.kernel.dk/linux-block: (294 commits)
  nvme: fix visibility of "uuid" ns attribute
  blk-mq: fixup some comment typos and lengths
  ide: ide-atapi: fix compile error with defining macro DEBUG
  blk-mq: improve tag waiting setup for non-shared tags
  brd: remove unused brd_mutex
  blk-mq: only run the hardware queue if IO is pending
  block: avoid null pointer dereference on null disk
  fs: guard_bio_eod() needs to consider partitions
  xtensa/simdisk: fix compile error
  nvme: expose subsys attribute to sysfs
  nvme: create 'slaves' and 'holders' entries for hidden controllers
  block: create 'slaves' and 'holders' entries for hidden gendisks
  nvme: also expose the namespace identification sysfs files for mpath nodes
  nvme: implement multipath access to nvme subsystems
  nvme: track shared namespaces
  nvme: introduce a nvme_ns_ids structure
  nvme: track subsystems
  block, nvme: Introduce blk_mq_req_flags_t
  block, scsi: Make SCSI quiesce and resume work reliably
  block: Add the QUEUE_FLAG_PREEMPT_ONLY request queue flag
  ...
</content>
</entry>
<entry>
<title>block, scsi: Make SCSI quiesce and resume work reliably</title>
<updated>2017-11-11T02:53:25Z</updated>
<author>
<name>Bart Van Assche</name>
<email>bart.vanassche@wdc.com</email>
</author>
<published>2017-11-09T18:49:58Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=3a0a529971ec4e2d933e9c7798db101dfb6b1aec'/>
<id>urn:sha1:3a0a529971ec4e2d933e9c7798db101dfb6b1aec</id>
<content type='text'>
The contexts from which a SCSI device can be quiesced or resumed are:
* Writing into /sys/class/scsi_device/*/device/state.
* SCSI parallel (SPI) domain validation.
* The SCSI device power management methods. See also scsi_bus_pm_ops.

It is essential during suspend and resume that neither the filesystem
state nor the filesystem metadata in RAM changes. This is why while
the hibernation image is being written or restored that SCSI devices
are quiesced. The SCSI core quiesces devices through scsi_device_quiesce()
and scsi_device_resume(). In the SDEV_QUIESCE state execution of
non-preempt requests is deferred. This is realized by returning
BLKPREP_DEFER from inside scsi_prep_state_check() for quiesced SCSI
devices. Avoid that a full queue prevents power management requests
to be submitted by deferring allocation of non-preempt requests for
devices in the quiesced state. This patch has been tested by running
the following commands and by verifying that after each resume the
fio job was still running:

for ((i=0; i&lt;10; i++)); do
  (
    cd /sys/block/md0/md &amp;&amp;
    while true; do
      [ "$(&lt;sync_action)" = "idle" ] &amp;&amp; echo check &gt; sync_action
      sleep 1
    done
  ) &amp;
  pids=($!)
  for d in /sys/class/block/sd*[a-z]; do
    bdev=${d#/sys/class/block/}
    hcil=$(readlink "$d/device")
    hcil=${hcil#../../../}
    echo 4 &gt; "$d/queue/nr_requests"
    echo 1 &gt; "/sys/class/scsi_device/$hcil/device/queue_depth"
    fio --name="$bdev" --filename="/dev/$bdev" --buffered=0 --bs=512 \
      --rw=randread --ioengine=libaio --numjobs=4 --iodepth=16       \
      --iodepth_batch=1 --thread --loops=$((2**31)) &amp;
    pids+=($!)
  done
  sleep 1
  echo "$(date) Hibernating ..." &gt;&gt;hibernate-test-log.txt
  systemctl hibernate
  sleep 10
  kill "${pids[@]}"
  echo idle &gt; /sys/block/md0/md/sync_action
  wait
  echo "$(date) Done." &gt;&gt;hibernate-test-log.txt
done

Reported-by: Oleksandr Natalenko &lt;oleksandr@natalenko.name&gt;
References: "I/O hangs after resuming from suspend-to-ram" (https://marc.info/?l=linux-block&amp;m=150340235201348).
Signed-off-by: Bart Van Assche &lt;bart.vanassche@wdc.com&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.com&gt;
Tested-by: Martin Steigerwald &lt;martin@lichtvoll.de&gt;
Tested-by: Oleksandr Natalenko &lt;oleksandr@natalenko.name&gt;
Cc: Martin K. Petersen &lt;martin.petersen@oracle.com&gt;
Cc: Ming Lei &lt;ming.lei@redhat.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Johannes Thumshirn &lt;jthumshirn@suse.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
</entry>
<entry>
<title>block: add a poll_fn callback to struct request_queue</title>
<updated>2017-11-03T16:31:48Z</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2017-11-02T18:29:54Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=ea435e1b9392a33deceaea2a16ebaa3397bead93'/>
<id>urn:sha1:ea435e1b9392a33deceaea2a16ebaa3397bead93</id>
<content type='text'>
That we we can also poll non blk-mq queues.  Mostly needed for
the NVMe multipath code, but could also be useful elsewhere.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Hannes Reinecke &lt;hare@suse.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
</entry>
<entry>
<title>fs/mpage.c: fix mpage_writepage() for pages with buffers</title>
<updated>2017-10-13T23:18:33Z</updated>
<author>
<name>Matthew Wilcox</name>
<email>willy@infradead.org</email>
</author>
<published>2017-10-13T22:58:15Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=f892760aa66a2d657deaf59538fb69433036767c'/>
<id>urn:sha1:f892760aa66a2d657deaf59538fb69433036767c</id>
<content type='text'>
When using FAT on a block device which supports rw_page, we can hit
BUG_ON(!PageLocked(page)) in try_to_free_buffers().  This is because we
call clean_buffers() after unlocking the page we've written.  Introduce
a new clean_page_buffers() which cleans all buffers associated with a
page and call it from within bdev_write_page().

[akpm@linux-foundation.org: s/PAGE_SIZE/~0U/ per Linus and Matthew]
Link: http://lkml.kernel.org/r/20171006211541.GA7409@bombadil.infradead.org
Signed-off-by: Matthew Wilcox &lt;mawilcox@microsoft.com&gt;
Reported-by: Toshi Kani &lt;toshi.kani@hpe.com&gt;
Reported-by: OGAWA Hirofumi &lt;hirofumi@mail.parknet.co.jp&gt;
Tested-by: Toshi Kani &lt;toshi.kani@hpe.com&gt;
Acked-by: Johannes Thumshirn &lt;jthumshirn@suse.de&gt;
Cc: Ross Zwisler &lt;ross.zwisler@linux.intel.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>fs/block_dev: remove vfs_msg() interface</title>
<updated>2017-10-12T18:30:24Z</updated>
<author>
<name>Rakesh Pandit</name>
<email>rakesh@tuxera.com</email>
</author>
<published>2017-10-12T16:58:10Z</published>
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<id>urn:sha1:7f66721a7d5bf6251f9c49aada9200c61ddcecc5</id>
<content type='text'>
Replaced by pr_err usage in commit ef51042472f5 ("block, dax: move
"select DAX" from BLOCK to FS_DAX")

Signed-off-by: Rakesh Pandit &lt;rakesh@tuxera.com&gt;
Acked-by: Ross Zwisler &lt;ross.zwisler@linux.intel.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
</entry>
<entry>
<title>Merge branch 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs</title>
<updated>2017-09-15T02:29:55Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2017-09-15T02:29:55Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=e253d98f5babbec7e6ced810f7335b265a7f7e83'/>
<id>urn:sha1:e253d98f5babbec7e6ced810f7335b265a7f7e83</id>
<content type='text'>
Pull nowait read support from Al Viro:
 "Support IOCB_NOWAIT for buffered reads and block devices"

* 'work.read_write' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  block_dev: support RFW_NOWAIT on block device nodes
  fs: support RWF_NOWAIT for buffered reads
  fs: support IOCB_NOWAIT in generic_file_buffered_read
  fs: pass iocb to do_generic_file_read
</content>
</entry>
<entry>
<title>block_dev: support RFW_NOWAIT on block device nodes</title>
<updated>2017-09-04T23:04:23Z</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2017-08-29T14:13:21Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=c35fc7a5abae9c154dd6f8c0b288462342facd45'/>
<id>urn:sha1:c35fc7a5abae9c154dd6f8c0b288462342facd45</id>
<content type='text'>
All support is already there in the generic code, we just need to wire
it up.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Jan Kara &lt;jack@suse.cz&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
<entry>
<title>block: replace bi_bdev with a gendisk pointer and partitions index</title>
<updated>2017-08-23T18:49:55Z</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2017-08-23T17:10:32Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=74d46992e0d9dee7f1f376de0d56d31614c8a17a'/>
<id>urn:sha1:74d46992e0d9dee7f1f376de0d56d31614c8a17a</id>
<content type='text'>
This way we don't need a block_device structure to submit I/O.  The
block_device has different life time rules from the gendisk and
request_queue and is usually only available when the block device node
is open.  Other callers need to explicitly create one (e.g. the lightnvm
passthrough code, or the new nvme multipathing code).

For the actual I/O path all that we need is the gendisk, which exists
once per block device.  But given that the block layer also does
partition remapping we additionally need a partition index, which is
used for said remapping in generic_make_request.

Note that all the block drivers generally want request_queue or
sometimes the gendisk, so this removes a layer of indirection all
over the stack.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
</entry>
<entry>
<title>block: cache the partition index in struct block_device</title>
<updated>2017-08-23T18:49:53Z</updated>
<author>
<name>Christoph Hellwig</name>
<email>hch@lst.de</email>
</author>
<published>2017-08-23T17:10:31Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=c2ee070fb00365d7841f6661dcdc7fbe6620bdf8'/>
<id>urn:sha1:c2ee070fb00365d7841f6661dcdc7fbe6620bdf8</id>
<content type='text'>
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
</content>
</entry>
<entry>
<title>Merge tag 'for-linus-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux</title>
<updated>2017-07-08T02:38:17Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2017-07-08T02:38:17Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=088737f44bbf6378745f5b57b035e57ee3dc4750'/>
<id>urn:sha1:088737f44bbf6378745f5b57b035e57ee3dc4750</id>
<content type='text'>
Pull Writeback error handling updates from Jeff Layton:
 "This pile represents the bulk of the writeback error handling fixes
  that I have for this cycle. Some of the earlier patches in this pile
  may look trivial but they are prerequisites for later patches in the
  series.

  The aim of this set is to improve how we track and report writeback
  errors to userland. Most applications that care about data integrity
  will periodically call fsync/fdatasync/msync to ensure that their
  writes have made it to the backing store.

  For a very long time, we have tracked writeback errors using two flags
  in the address_space: AS_EIO and AS_ENOSPC. Those flags are set when a
  writeback error occurs (via mapping_set_error) and are cleared as a
  side-effect of filemap_check_errors (as you noted yesterday). This
  model really sucks for userland.

  Only the first task to call fsync (or msync or fdatasync) will see the
  error. Any subsequent task calling fsync on a file will get back 0
  (unless another writeback error occurs in the interim). If I have
  several tasks writing to a file and calling fsync to ensure that their
  writes got stored, then I need to have them coordinate with one
  another. That's difficult enough, but in a world of containerized
  setups that coordination may even not be possible.

  But wait...it gets worse!

  The calls to filemap_check_errors can be buried pretty far down in the
  call stack, and there are internal callers of filemap_write_and_wait
  and the like that also end up clearing those errors. Many of those
  callers ignore the error return from that function or return it to
  userland at nonsensical times (e.g. truncate() or stat()). If I get
  back -EIO on a truncate, there is no reason to think that it was
  because some previous writeback failed, and a subsequent fsync() will
  (incorrectly) return 0.

  This pile aims to do three things:

   1) ensure that when a writeback error occurs that that error will be
      reported to userland on a subsequent fsync/fdatasync/msync call,
      regardless of what internal callers are doing

   2) report writeback errors on all file descriptions that were open at
      the time that the error occurred. This is a user-visible change,
      but I think most applications are written to assume this behavior
      anyway. Those that aren't are unlikely to be hurt by it.

   3) document what filesystems should do when there is a writeback
      error. Today, there is very little consistency between them, and a
      lot of cargo-cult copying. We need to make it very clear what
      filesystems should do in this situation.

  To achieve this, the set adds a new data type (errseq_t) and then
  builds new writeback error tracking infrastructure around that. Once
  all of that is in place, we change the filesystems to use the new
  infrastructure for reporting wb errors to userland.

  Note that this is just the initial foray into cleaning up this mess.
  There is a lot of work remaining here:

   1) convert the rest of the filesystems in a similar fashion. Once the
      initial set is in, then I think most other fs' will be fairly
      simple to convert. Hopefully most of those can in via individual
      filesystem trees.

   2) convert internal waiters on writeback to use errseq_t for
      detecting errors instead of relying on the AS_* flags. I have some
      draft patches for this for ext4, but they are not quite ready for
      prime time yet.

  This was a discussion topic this year at LSF/MM too. If you're
  interested in the gory details, LWN has some good articles about this:

      https://lwn.net/Articles/718734/
      https://lwn.net/Articles/724307/"

* tag 'for-linus-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
  btrfs: minimal conversion to errseq_t writeback error reporting on fsync
  xfs: minimal conversion to errseq_t writeback error reporting
  ext4: use errseq_t based error handling for reporting data writeback errors
  fs: convert __generic_file_fsync to use errseq_t based reporting
  block: convert to errseq_t based writeback error tracking
  dax: set errors in mapping when writeback fails
  Documentation: flesh out the section in vfs.txt on storing and reporting writeback errors
  mm: set both AS_EIO/AS_ENOSPC and errseq_t in mapping_set_error
  fs: new infrastructure for writeback error handling and reporting
  lib: add errseq_t type and infrastructure for handling it
  mm: don't TestClearPageError in __filemap_fdatawait_range
  mm: clear AS_EIO/AS_ENOSPC when writeback initiation fails
  jbd2: don't clear and reset errors after waiting on writeback
  buffer: set errors in mapping at the time that the error occurs
  fs: check for writeback errors after syncing out buffers in generic_file_fsync
  buffer: use mapping_set_error instead of setting the flag
  mm: fix mapping_set_error call in me_pagecache_dirty
</content>
</entry>
</feed>
