linux.git/fs/xfs, branch v4.17

xfs: cap the length of deduplication requests

2018-05-02T16:21:33+00:00

Since deduplication potentially has to read in all the pages in both
files in order to compare the contents, cap the deduplication request
length at MAX_RW_COUNT/2 (roughly 1GB) so that we have /some/ upper bound
on the request length and can't just lock up the kernel forever.  Found
by running generic/304 after commit 1ddae54555b62 ("common/rc: add
missing 'local' keywords").

Reported-by: matorola@gmail.com
Signed-off-by: Darrick J. Wong 
Reviewed-by: Carlos Maiolino

xfs: don't fail when converting shortform attr to long form during ATTR_REPLACE

2018-04-18T02:10:15+00:00

Kanda Motohiro reported that expanding a tiny xattr into a large xattr
fails on XFS because we remove the tiny xattr from a shortform fork and
then try to re-add it after converting the fork to extents format having
not removed the ATTR_REPLACE flag.  This fails because the attr is no
longer present, causing a fs shutdown.

This is derived from the patch in his bug report, but we really
shouldn't ignore a nonzero retval from the remove call.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199119
Reported-by: kanda.motohiro@gmail.com
Reviewed-by: Dave Chinner 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Darrick J. Wong

xfs: prevent creating negative-sized file via INSERT_RANGE

2018-04-18T00:29:11+00:00

During the "insert range" fallocate operation, i_size grows by the
specified 'len' bytes.  XFS verifies that i_size + len < s_maxbytes, as
it should.  But this comparison is done using the signed 'loff_t', and
'i_size + len' can wrap around to a negative value, causing the check to
incorrectly pass, resulting in an inode with "negative" i_size.  This is
possible on 64-bit platforms, where XFS sets s_maxbytes = LLONG_MAX.
ext4 and f2fs don't run into this because they set a smaller s_maxbytes.

Fix it by using subtraction instead.

Reproducer:
    xfs_io -f file -c "truncate $(((1<<63)-1))" -c "finsert 0 4096"

Fixes: a904b1ca5751 ("xfs: Add support FALLOC_FL_INSERT_RANGE for fallocate")
Cc:  # v4.1+
Originally-From: Eric Biggers 
Signed-off-by: Eric Biggers 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Darrick J. Wong 
[darrick: fix signed integer addition overflow too]
Signed-off-by: Darrick J. Wong

xfs: set format back to extents if xfs_bmap_extents_to_btree

2018-04-18T00:10:17+00:00

If xfs_bmap_extents_to_btree fails in a mode where we call
xfs_iroot_realloc(-1) to de-allocate the root, set the
format back to extents.

Otherwise we can assume we can dereference ifp->if_broot
based on the XFS_DINODE_FMT_BTREE format, and crash.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199423
Signed-off-by: Eric Sandeen 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

xfs: enhance dinode verifier

2018-04-18T00:10:17+00:00

Add several more validations to xfs_dinode_verify:

- For LOCAL data fork formats, di_nextents must be 0.
- For LOCAL attr fork formats, di_anextents must be 0.
- For inodes with no attr fork offset,
  - format must be XFS_DINODE_FMT_EXTENTS if set at all
  - di_anextents must be 0.

Thanks to dchinner for pointing out a couple related checks I had
forgotten to add.

Signed-off-by: Eric Sandeen 
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199377
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

Merge tag 'xfs-4.17-merge-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

2018-04-12T20:28:22+00:00

Pull more xfs updates from Darrick Wong:
 "Most of these are code cleanups, but there are a couple of notable
  use-after-free bug fixes.

  This series has been run through a full xfstests run over the week and
  through a quick xfstests run against this morning's master, with no
  major failures reported.

   - clean up unnecessary function call parameters

   - fix a use-after-free bug when aborting logging intents

   - refactor filestreams state data to avoid use-after-free bug

   - fix incorrect removal of cow extents when truncating extended
     attributes.

   - refactor open-coded __set_page_dirty in favor of using vfs
     function.

   - fix a deadlock when fstrim and fs shutdown race"

* tag 'xfs-4.17-merge-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  Force log to disk before reading the AGF during a fstrim
  Export __set_page_dirty
  xfs: only cancel cow blocks when truncating the data fork
  xfs: non-scrub - remove unused function parameters
  xfs: remove filestream item xfs_inode reference
  xfs: fix intent use-after-free on abort
  xfs: Remove "committed" argument of xfs_dir_ialloc

export __set_page_dirty

2018-04-11T17:28:39+00:00

XFS currently contains a copy-and-paste of __set_page_dirty().  Export
it from buffer.c instead.

Link: http://lkml.kernel.org/r/20180313132639.17387-6-willy@infradead.org
Signed-off-by: Matthew Wilcox 
Acked-by: Jeff Layton 
Reviewed-by: Darrick J. Wong 
Cc: Ryusuke Konishi 
Cc: Dave Chinner 
Cc: Will Deacon 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Force log to disk before reading the AGF during a fstrim

2018-04-11T05:39:04+00:00

Forcing the log to disk after reading the agf is wrong, we might be
calling xfs_log_force with XFS_LOG_SYNC with a metadata lock held.

This can cause a deadlock when racing a fstrim with a filesystem
shutdown.

The deadlock has been identified due a miscalculation bug in device-mapper
dm-thin, which returns lack of space to its users earlier than the device itself
really runs out of space, changing the device-mapper volume into an error state.

The problem happened while filling the filesystem with a single file,
triggering the bug in device-mapper, consequently causing an IO error
and shutting down the filesystem.

If such file is removed, and fstrim executed before the XFS finishes the
shut down process, the fstrim process will end up holding the buffer
lock, and going to sleep on the cil wait queue.

At this point, the shut down process will try to wake up all the threads
waiting on the cil wait queue, but for this, it will try to hold the
same buffer log already held my the fstrim, locking up the filesystem.

Signed-off-by: Carlos Maiolino 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

Export __set_page_dirty

2018-04-11T05:39:01+00:00

XFS currently contains a copy-and-paste of __set_page_dirty().  Export
it from buffer.c instead.

Signed-off-by: Matthew Wilcox 
Acked-by: Jeff Layton 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

Merge tag 'libnvdimm-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2018-04-10T17:25:57+00:00

Pull libnvdimm updates from Dan Williams:
"This cycle was was not something I ever want to repeat as there were
several late changes that have only now just settled.

Half of the branch up to commit d2c997c0f145 ("fs, dax: use
page->mapping to warn...") have been in -next for several releases.
The of_pmem driver and the address range scrub rework were late
arrivals, and the dax work was scaled back at the last moment.

The of_pmem driver missed a previous merge window due to an oversight.
A sense of obligation to rectify that miss is why it is included for
4.17. It has acks from PowerPC folks. Stephen reported a build failure
that only occurs when merging it with your latest tree, for now I have
fixed that up by disabling modular builds of of_pmem. A test merge
with your tree has received a build success report from the 0day robot
over 156 configs.

An initial version of the ARS rework was submitted before the merge
window. It is self contained to libnvdimm, a net code reduction, and
passing all unit tests.

The filesystem-dax changes are based on the wait_var_event()
functionality from tip/sched/core. However, late review feedback
showed that those changes regressed truncate performance to a large
degree. The branch was rewound to drop the truncate behavior change
and now only includes preparation patches and cleanups (with full acks
and reviews). The finalization of this dax-dma-vs-trnucate work will
need to wait for 4.18.

Summary:

- A rework of the filesytem-dax implementation provides for detection
of unmap operations (truncate / hole punch) colliding with
in-progress device-DMA. A fix for these collisions remains a
work-in-progress pending resolution of truncate latency and
starvation regressions.

- The of_pmem driver expands the users of libnvdimm outside of x86
and ACPI to describe an implementation of persistent memory on
PowerPC with Open Firmware / Device tree.

- Address Range Scrub (ARS) handling is completely rewritten to
account for the fact that ARS may run for 100s of seconds and there
is no platform defined way to cancel it. ARS will now no longer
block namespace initialization.

- The NVDIMM Namespace Label implementation is updated to handle
label areas as small as 1K, down from 128K.

- Miscellaneous cleanups and updates to unit test infrastructure"

* tag 'libnvdimm-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (39 commits)
libnvdimm, of_pmem: workaround OF_NUMA=n build error
nfit, address-range-scrub: add module option to skip initial ars
nfit, address-range-scrub: rework and simplify ARS state machine
nfit, address-range-scrub: determine one platform max_ars value
powerpc/powernv: Create platform devs for nvdimm buses
doc/devicetree: Persistent memory region bindings
libnvdimm: Add device-tree based driver
libnvdimm: Add of_node to region and bus descriptors
libnvdimm, region: quiet region probe
libnvdimm, namespace: use a safe lookup for dimm device name
libnvdimm, dimm: fix dpa reservation vs uninitialized label area
libnvdimm, testing: update the default smart ctrl_temperature
libnvdimm, testing: Add emulation for smart injection commands
nfit, address-range-scrub: introduce nfit_spa->ars_state
libnvdimm: add an api to cast a 'struct nd_region' to its 'struct device'
nfit, address-range-scrub: fix scrub in-progress reporting
dax, dm: allow device-mapper to operate without dax support
dax: introduce CONFIG_DAX_DRIVER
fs, dax: use page->mapping to warn if truncate collides with a busy page
ext2, dax: introduce ext2_dax_aops
...