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Author SHA1 Message Date
Linus Torvalds
088737f44b Writeback error handling fixes (pile #2)
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Merge tag 'for-linus-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux

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
2017-07-07 19:38:17 -07:00
Jeff Layton
6acec592c6 ext4: use errseq_t based error handling for reporting data writeback errors
Add a call to filemap_report_wb_err at the end of ext4_sync_file. This
will ensure that we check and advance the errseq_t in the file, which
allows us to track and report errors on all open fds when they occur.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
2017-07-06 07:02:30 -04:00
Jens Axboe
0127251c45 ext4: add support for passing in write hints for buffered writes
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:05:44 -06:00
Goldwyn Rodrigues
728fbc0e10 ext4: nowait aio support
Return EAGAIN if any of the following checks fail for direct I/O:
  + i_rwsem is lockable
  + Writing beyond end of file (will trigger allocation)
  + Blocks are not allocated at the write location

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Christoph Hellwig
fdd050b5b3 Merge branch 'uuid-types' of bombadil.infradead.org:public_git/uuid into nvme-base 2017-06-13 11:45:14 +02:00
Jens Axboe
8f66439eec Linux 4.12-rc5
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Merge tag 'v4.12-rc5' into for-4.13/block

We've already got a few conflicts and upcoming work depends on some of the
changes that have gone into mainline as regression fixes for this series.

Pull in 4.12-rc5 to resolve these conflicts and make it easier on down stream
trees to continue working on 4.13 changes.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-12 08:30:13 -06:00
Christoph Hellwig
4e4cbee93d block: switch bios to blk_status_t
Replace bi_error with a new bi_status to allow for a clear conversion.
Note that device mapper overloaded bi_error with a private value, which
we'll have to keep arround at least for now and thus propagate to a
proper blk_status_t value.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-09 09:27:32 -06:00
Christoph Hellwig
85787090a2 fs: switch ->s_uuid to uuid_t
For some file systems we still memcpy into it, but in various places this
already allows us to use the proper uuid helpers.  More to come..

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (Changes to IMA/EVM)
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2017-06-05 16:59:12 +02:00
Jan Kara
67a7d5f561 ext4: fix fdatasync(2) after extent manipulation operations
Currently, extent manipulation operations such as hole punch, range
zeroing, or extent shifting do not record the fact that file data has
changed and thus fdatasync(2) has a work to do. As a result if we crash
e.g. after a punch hole and fdatasync, user can still possibly see the
punched out data after journal replay. Test generic/392 fails due to
these problems.

Fix the problem by properly marking that file data has changed in these
operations.

CC: stable@vger.kernel.org
Fixes: a4bb6b64e3
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-29 13:24:55 -04:00
Jan Kara
a056bdaae7 ext4: fix data corruption for mmap writes
mpage_submit_page() can race with another process growing i_size and
writing data via mmap to the written-back page. As mpage_submit_page()
samples i_size too early, it may happen that ext4_bio_write_page()
zeroes out too large tail of the page and thus corrupts user data.

Fix the problem by sampling i_size only after the page has been
write-protected in page tables by clear_page_dirty_for_io() call.

Reported-by: Michael Zimmer <michael@swarm64.com>
CC: stable@vger.kernel.org
Fixes: cb20d51883
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-26 17:45:45 -04:00
Jan Kara
4f8caa60a5 ext4: fix data corruption with EXT4_GET_BLOCKS_ZERO
When ext4_map_blocks() is called with EXT4_GET_BLOCKS_ZERO to zero-out
allocated blocks and these blocks are actually converted from unwritten
extent the following race can happen:

CPU0					CPU1

page fault				page fault
...					...
ext4_map_blocks()
  ext4_ext_map_blocks()
    ext4_ext_handle_unwritten_extents()
      ext4_ext_convert_to_initialized()
	- zero out converted extent
	ext4_zeroout_es()
	  - inserts extent as initialized in status tree

					ext4_map_blocks()
					  ext4_es_lookup_extent()
					    - finds initialized extent
					write data
  ext4_issue_zeroout()
    - zeroes out new extent overwriting data

This problem can be reproduced by generic/340 for the fallocated case
for the last block in the file.

Fix the problem by avoiding zeroing out the area we are mapping with
ext4_map_blocks() in ext4_ext_convert_to_initialized(). It is pointless
to zero out this area in the first place as the caller asked us to
convert the area to initialized because he is just going to write data
there before the transaction finishes. To achieve this we delete the
special case of zeroing out full extent as that will be handled by the
cases below zeroing only the part of the extent that needs it. We also
instruct ext4_split_extent() that the middle of extent being split
contains data so that ext4_split_extent_at() cannot zero out full extent
in case of ENOSPC.

CC: stable@vger.kernel.org
Fixes: 12735f8819
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-26 17:40:52 -04:00
Tahsin Erdogan
b8cb5a545c ext4: fix quota charging for shared xattr blocks
ext4_xattr_block_set() calls dquot_alloc_block() to charge for an xattr
block when new references are made. However if dquot_initialize() hasn't
been called on an inode, request for charging is effectively ignored
because ext4_inode_info->i_dquot is not initialized yet.

Add dquot_initialize() to call paths that lead to ext4_xattr_block_set().

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-05-24 18:24:07 -04:00
Eric Biggers
c41d342b39 ext4: remove redundant check for encrypted file on dio write path
Currently we don't allow direct I/O on encrypted regular files, so in
such cases we return 0 early in ext4_direct_IO().  There was also an
additional BUG_ON() check in ext4_direct_IO_write(), but it can never be
hit because of the earlier check for the exact same condition in
ext4_direct_IO().  There was also no matching check on the read path,
which made the write path specific check seem very ad-hoc.

Just remove the unnecessary BUG_ON().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: David Gstir <david@sigma-star.at>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-05-24 18:20:31 -04:00
Eric Biggers
d6b975504e ext4: remove unused d_name argument from ext4_search_dir() et al.
Now that we are passing a struct ext4_filename, we do not need to pass
around the original struct qstr too.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-05-24 18:10:49 -04:00
Eric Biggers
e5465795ca ext4: fix off-by-one error when writing back pages before dio read
The 'lend' argument of filemap_write_and_wait_range() is inclusive, so
we need to subtract 1 from pos + count.

Note that 'count' is guaranteed to be nonzero since
ext4_file_read_iter() returns early when given a 0 count.

Fixes: 16c5468859 ("ext4: Allow parallel DIO reads")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-05-24 18:05:29 -04:00
Eryu Guan
624327f879 ext4: fix off-by-one on max nr_pages in ext4_find_unwritten_pgoff()
ext4_find_unwritten_pgoff() is used to search for offset of hole or
data in page range [index, end] (both inclusive), and the max number
of pages to search should be at least one, if end == index.
Otherwise the only page is missed and no hole or data is found,
which is not correct.

When block size is smaller than page size, this can be demonstrated
by preallocating a file with size smaller than page size and writing
data to the last block. E.g. run this xfs_io command on a 1k block
size ext4 on x86_64 host.

  # xfs_io -fc "falloc 0 3k" -c "pwrite 2k 1k" \
  	    -c "seek -d 0" /mnt/ext4/testfile
  wrote 1024/1024 bytes at offset 2048
  1 KiB, 1 ops; 0.0000 sec (42.459 MiB/sec and 43478.2609 ops/sec)
  Whence  Result
  DATA    EOF

Data at offset 2k was missed, and lseek(2) returned ENXIO.

This is unconvered by generic/285 subtest 07 and 08 on ppc64 host,
where pagesize is 64k. Because a recent change to generic/285
reduced the preallocated file size to smaller than 64k.

Signed-off-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2017-05-24 18:02:20 -04:00
Konstantin Khlebnikov
887a973061 ext4: keep existing extra fields when inode expands
ext4_expand_extra_isize() should clear only space between old and new
size.

Fixes: 6dd4ee7cab # v2.6.23
Cc: stable@vger.kernel.org
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-21 22:36:23 -04:00
Konstantin Khlebnikov
9651e6b2e2 ext4: handle the rest of ext4_mb_load_buddy() ENOMEM errors
I've got another report about breaking ext4 by ENOMEM error returned from
ext4_mb_load_buddy() caused by memory shortage in memory cgroup.
This time inside ext4_discard_preallocations().

This patch replaces ext4_error() with ext4_warning() where errors returned
from ext4_mb_load_buddy() are not fatal and handled by caller:
* ext4_mb_discard_group_preallocations() - called before generating ENOSPC,
  we'll try to discard other group or return ENOSPC into user-space.
* ext4_trim_all_free() - just stop trimming and return ENOMEM from ioctl.

Some callers cannot handle errors, thus __GFP_NOFAIL is used for them:
* ext4_discard_preallocations()
* ext4_mb_discard_lg_preallocations()

Fixes: adb7ef600c ("ext4: use __GFP_NOFAIL in ext4_free_blocks()")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-21 22:35:23 -04:00
Jan Kara
3f1d5bad3f ext4: fix off-by-in in loop termination in ext4_find_unwritten_pgoff()
There is an off-by-one error in loop termination conditions in
ext4_find_unwritten_pgoff() since 'end' may index a page beyond end of
desired range if 'endoff' is page aligned. It doesn't have any visible
effects but still it is good to fix it.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-21 22:34:23 -04:00
Jan Kara
7d95eddf31 ext4: fix SEEK_HOLE
Currently, SEEK_HOLE implementation in ext4 may both return that there's
a hole at some offset although that offset already has data and skip
some holes during a search for the next hole. The first problem is
demostrated by:

xfs_io -c "falloc 0 256k" -c "pwrite 0 56k" -c "seek -h 0" file
wrote 57344/57344 bytes at offset 0
56 KiB, 14 ops; 0.0000 sec (2.054 GiB/sec and 538461.5385 ops/sec)
Whence	Result
HOLE	0

Where we can see that SEEK_HOLE wrongly returned offset 0 as containing
a hole although we have written data there. The second problem can be
demonstrated by:

xfs_io -c "falloc 0 256k" -c "pwrite 0 56k" -c "pwrite 128k 8k"
       -c "seek -h 0" file

wrote 57344/57344 bytes at offset 0
56 KiB, 14 ops; 0.0000 sec (1.978 GiB/sec and 518518.5185 ops/sec)
wrote 8192/8192 bytes at offset 131072
8 KiB, 2 ops; 0.0000 sec (2 GiB/sec and 500000.0000 ops/sec)
Whence	Result
HOLE	139264

Where we can see that hole at offsets 56k..128k has been ignored by the
SEEK_HOLE call.

The underlying problem is in the ext4_find_unwritten_pgoff() which is
just buggy. In some cases it fails to update returned offset when it
finds a hole (when no pages are found or when the first found page has
higher index than expected), in some cases conditions for detecting hole
are just missing (we fail to detect a situation where indices of
returned pages are not contiguous).

Fix ext4_find_unwritten_pgoff() to properly detect non-contiguous page
indices and also handle all cases where we got less pages then expected
in one place and handle it properly there.

CC: stable@vger.kernel.org
Fixes: c8c0df241c
CC: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-21 22:33:23 -04:00
Jan Kara
964edf66bf ext4: clear lockdep subtype for quota files on quota off
Quota files have special ranking of i_data_sem lock. We inform lockdep
about it when turning on quotas however when turning quotas off, we
don't clear the lockdep subclass from i_data_sem lock and thus when the
inode gets later reused for a normal file or directory, lockdep gets
confused and complains about possible deadlocks. Fix the problem by
resetting lockdep subclass of i_data_sem on quota off.

Cc: stable@vger.kernel.org
Fixes: daf647d2dd
Reported-and-tested-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-21 22:31:23 -04:00
Dan Williams
f5705aa8cf dax, xfs, ext4: compile out iomap-dax paths in the FS_DAX=n case
Tetsuo reports:

  fs/built-in.o: In function `xfs_file_iomap_end':
  xfs_iomap.c:(.text+0xe0ef9): undefined reference to `put_dax'
  fs/built-in.o: In function `xfs_file_iomap_begin':
  xfs_iomap.c:(.text+0xe1a7f): undefined reference to `dax_get_by_host'
  make: *** [vmlinux] Error 1
  $ grep DAX .config
  CONFIG_DAX=m
  # CONFIG_DEV_DAX is not set
  # CONFIG_FS_DAX is not set

When FS_DAX=n we can/must throw away the dax code in filesystems.
Implement 'fs_' versions of dax_get_by_host() and put_dax() that are
nops in the FS_DAX=n case.

Cc: <linux-xfs@vger.kernel.org>
Cc: <linux-ext4@vger.kernel.org>
Cc: Jan Kara <jack@suse.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Fixes: ef51042472 ("block, dax: move 'select DAX' from BLOCK to FS_DAX")
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-13 17:52:16 -07:00
Linus Torvalds
1251704a63 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "15 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm, docs: update memory.stat description with workingset* entries
  mm: vmscan: scan until it finds eligible pages
  mm, thp: copying user pages must schedule on collapse
  dax: fix PMD data corruption when fault races with write
  dax: fix data corruption when fault races with write
  ext4: return to starting transaction in ext4_dax_huge_fault()
  mm: fix data corruption due to stale mmap reads
  dax: prevent invalidation of mapped DAX entries
  Tigran has moved
  mm, vmalloc: fix vmalloc users tracking properly
  mm/khugepaged: add missed tracepoint for collapse_huge_page_swapin
  gcov: support GCC 7.1
  mm, vmstat: Remove spurious WARN() during zoneinfo print
  time: delete current_fs_time()
  hwpoison, memcg: forcibly uncharge LRU pages
2017-05-13 09:49:35 -07:00
Jan Kara
fb26a1cbed ext4: return to starting transaction in ext4_dax_huge_fault()
DAX will return to locking exceptional entry before mapping blocks for a
page fault to fix possible races with concurrent writes.  To avoid lock
inversion between exceptional entry lock and transaction start, start
the transaction already in ext4_dax_huge_fault().

Fixes: 9f141d6ef6
Link: http://lkml.kernel.org/r/20170510085419.27601-4-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-12 15:57:16 -07:00
Linus Torvalds
0fcc3ab23d Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm fixes from Dan Williams:
 "Incremental fixes and a small feature addition on top of the main
  libnvdimm 4.12 pull request:

   - Geert noticed that tinyconfig was bloated by BLOCK selecting DAX.
     The size regression is fixed by moving all dax helpers into the
     dax-core and only specifying "select DAX" for FS_DAX and
     dax-capable drivers. He also asked for clarification of the
     NR_DEV_DAX config option which, on closer look, does not need to be
     a config option at all. Mike also throws in a DEV_DAX_PMEM fixup
     for good measure.

   - Ben's attention to detail on -stable patch submissions caught a
     case where the recent fixes to arch_copy_from_iter_pmem() missed a
     condition where we strand dirty data in the cache. This is tagged
     for -stable and will also be included in the rework of the pmem api
     to a proposed {memcpy,copy_user}_flushcache() interface for 4.13.

   - Vishal adds a feature that missed the initial pull due to pending
     review feedback. It allows the kernel to clear media errors when
     initializing a BTT (atomic sector update driver) instance on a pmem
     namespace.

   - Ross noticed that the dax_device + dax_operations conversion broke
     __dax_zero_page_range(). The nvdimm unit tests fail to check this
     path, but xfstests immediately trips over it. No excuse for missing
     this before submitting the 4.12 pull request.

  These all pass the nvdimm unit tests and an xfstests spot check. The
  set has received a build success notification from the kbuild robot"

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  filesystem-dax: fix broken __dax_zero_page_range() conversion
  libnvdimm, btt: ensure that initializing metadata clears poison
  libnvdimm: add an atomic vs process context flag to rw_bytes
  x86, pmem: Fix cache flushing for iovec write < 8 bytes
  device-dax: kill NR_DEV_DAX
  block, dax: move "select DAX" from BLOCK to FS_DAX
  device-dax: Tell kbuild DEV_DAX_PMEM depends on DEV_DAX
2017-05-12 15:43:10 -07:00
Linus Torvalds
bf5f89463f Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:

 - the rest of MM

 - various misc things

 - procfs updates

 - lib/ updates

 - checkpatch updates

 - kdump/kexec updates

 - add kvmalloc helpers, use them

 - time helper updates for Y2038 issues. We're almost ready to remove
   current_fs_time() but that awaits a btrfs merge.

 - add tracepoints to DAX

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits)
  drivers/staging/ccree/ssi_hash.c: fix build with gcc-4.4.4
  selftests/vm: add a test for virtual address range mapping
  dax: add tracepoint to dax_insert_mapping()
  dax: add tracepoint to dax_writeback_one()
  dax: add tracepoints to dax_writeback_mapping_range()
  dax: add tracepoints to dax_load_hole()
  dax: add tracepoints to dax_pfn_mkwrite()
  dax: add tracepoints to dax_iomap_pte_fault()
  mtd: nand: nandsim: convert to memalloc_noreclaim_*()
  treewide: convert PF_MEMALLOC manipulations to new helpers
  mm: introduce memalloc_noreclaim_{save,restore}
  mm: prevent potential recursive reclaim due to clearing PF_MEMALLOC
  mm/huge_memory.c: deposit a pgtable for DAX PMD faults when required
  mm/huge_memory.c: use zap_deposited_table() more
  time: delete CURRENT_TIME_SEC and CURRENT_TIME
  gfs2: replace CURRENT_TIME with current_time
  apparmorfs: replace CURRENT_TIME with current_time()
  lustre: replace CURRENT_TIME macro
  fs: ubifs: replace CURRENT_TIME_SEC with current_time
  fs: ufs: use ktime_get_real_ts64() for birthtime
  ...
2017-05-08 18:17:56 -07:00
Michal Hocko
a7c3e901a4 mm: introduce kv[mz]alloc helpers
Patch series "kvmalloc", v5.

There are many open coded kmalloc with vmalloc fallback instances in the
tree.  Most of them are not careful enough or simply do not care about
the underlying semantic of the kmalloc/page allocator which means that
a) some vmalloc fallbacks are basically unreachable because the kmalloc
part will keep retrying until it succeeds b) the page allocator can
invoke a really disruptive steps like the OOM killer to move forward
which doesn't sound appropriate when we consider that the vmalloc
fallback is available.

As it can be seen implementing kvmalloc requires quite an intimate
knowledge if the page allocator and the memory reclaim internals which
strongly suggests that a helper should be implemented in the memory
subsystem proper.

Most callers, I could find, have been converted to use the helper
instead.  This is patch 6.  There are some more relying on __GFP_REPEAT
in the networking stack which I have converted as well and Eric Dumazet
was not opposed [2] to convert them as well.

[1] http://lkml.kernel.org/r/20170130094940.13546-1-mhocko@kernel.org
[2] http://lkml.kernel.org/r/1485273626.16328.301.camel@edumazet-glaptop3.roam.corp.google.com

This patch (of 9):

Using kmalloc with the vmalloc fallback for larger allocations is a
common pattern in the kernel code.  Yet we do not have any common helper
for that and so users have invented their own helpers.  Some of them are
really creative when doing so.  Let's just add kv[mz]alloc and make sure
it is implemented properly.  This implementation makes sure to not make
a large memory pressure for > PAGE_SZE requests (__GFP_NORETRY) and also
to not warn about allocation failures.  This also rules out the OOM
killer as the vmalloc is a more approapriate fallback than a disruptive
user visible action.

This patch also changes some existing users and removes helpers which
are specific for them.  In some cases this is not possible (e.g.
ext4_kvmalloc, libcfs_kvzalloc) because those seems to be broken and
require GFP_NO{FS,IO} context which is not vmalloc compatible in general
(note that the page table allocation is GFP_KERNEL).  Those need to be
fixed separately.

While we are at it, document that __vmalloc{_node} about unsupported gfp
mask because there seems to be a lot of confusion out there.
kvmalloc_node will warn about GFP_KERNEL incompatible (which are not
superset) flags to catch new abusers.  Existing ones would have to die
slowly.

[sfr@canb.auug.org.au: f2fs fixup]
  Link: http://lkml.kernel.org/r/20170320163735.332e64b7@canb.auug.org.au
Link: http://lkml.kernel.org/r/20170306103032.2540-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>	[ext4 part]
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:12 -07:00
Linus Torvalds
677375cef8 Only bug fixes and cleanups for this merge window.
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Merge tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt

Pull fscrypt updates from Ted Ts'o:
 "Only bug fixes and cleanups for this merge window"

* tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt:
  fscrypt: correct collision claim for digested names
  MAINTAINERS: fscrypt: update mailing list, patchwork, and git
  ext4: clean up ext4_match() and callers
  f2fs: switch to using fscrypt_match_name()
  ext4: switch to using fscrypt_match_name()
  fscrypt: introduce helper function for filename matching
  fscrypt: avoid collisions when presenting long encrypted filenames
  f2fs: check entire encrypted bigname when finding a dentry
  ubifs: check for consistent encryption contexts in ubifs_lookup()
  f2fs: sync f2fs_lookup() with ext4_lookup()
  ext4: remove "nokey" check from ext4_lookup()
  fscrypt: fix context consistency check when key(s) unavailable
  fscrypt: Remove __packed from fscrypt_policy
  fscrypt: Move key structure and constants to uapi
  fscrypt: remove fscrypt_symlink_data_len()
  fscrypt: remove unnecessary checks for NULL operations
2017-05-08 11:40:34 -07:00
Linus Torvalds
dd727dad37 Add GETFSMAP support; some performance improvements for very large
file systems and for random write workloads into a preallocated file;
 bug fixes and cleanups.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:

 - add GETFSMAP support

 - some performance improvements for very large file systems and for
   random write workloads into a preallocated file

 - bug fixes and cleanups.

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  jbd2: cleanup write flags handling from jbd2_write_superblock()
  ext4: mark superblock writes synchronous for nobarrier mounts
  ext4: inherit encryption xattr before other xattrs
  ext4: replace BUG_ON with WARN_ONCE in ext4_end_bio()
  ext4: avoid unnecessary transaction stalls during writeback
  ext4: preload block group descriptors
  ext4: make ext4_shutdown() static
  ext4: support GETFSMAP ioctls
  vfs: add common GETFSMAP ioctl definitions
  ext4: evict inline data when writing to memory map
  ext4: remove ext4_xattr_check_entry()
  ext4: rename ext4_xattr_check_names() to ext4_xattr_check_entries()
  ext4: merge ext4_xattr_list() into ext4_listxattr()
  ext4: constify static data that is never modified
  ext4: trim return value and 'dir' argument from ext4_insert_dentry()
  jbd2: fix dbench4 performance regression for 'nobarrier' mounts
  jbd2: Fix lockdep splat with generic/270 test
  mm: retry writepages() on ENOMEM when doing an data integrity writeback
2017-05-08 11:30:05 -07:00
Dan Williams
ef51042472 block, dax: move "select DAX" from BLOCK to FS_DAX
For configurations that do not enable DAX filesystems or drivers, do not
require the DAX core to be built.

Given that the 'direct_access' method has been removed from
'block_device_operations', we can also go ahead and remove the
block-related dax helper functions from fs/block_dev.c to
drivers/dax/super.c. This keeps dax details out of the block layer and
lets the DAX core be built as a module in the FS_DAX=n case.

Filesystems need to include dax.h to call bdev_dax_supported().

Cc: linux-xfs@vger.kernel.org
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-08 10:55:27 -07:00
Linus Torvalds
53ef7d0e20 libnvdimm for 4.12
* Region media error reporting: A libnvdimm region device is the parent
 to one or more namespaces. To date, media errors have been reported via
 the "badblocks" attribute attached to pmem block devices for namespaces
 in "raw" or "memory" mode. Given that namespaces can be in "device-dax"
 or "btt-sector" mode this new interface reports media errors
 generically, i.e. independent of namespace modes or state. This
 subsequently allows userspace tooling to craft "ACPI 6.1 Section
 9.20.7.6 Function Index 4 - Clear Uncorrectable Error" requests and
 submit them via the ioctl path for NVDIMM root bus devices.
 
 * Introduce 'struct dax_device' and 'struct dax_operations': Prompted by
 a request from Linus and feedback from Christoph this allows for dax
 capable drivers to publish their own custom dax operations. This fixes
 the broken assumption that all dax operations are related to a
 persistent memory device, and makes it easier for other architectures
 and platforms to add customized persistent memory support.
 
 * 'libnvdimm' core updates: A new "deep_flush" sysfs attribute is
 available for storage appliance applications to manually trigger memory
 controllers to drain write-pending buffers that would otherwise be
 flushed automatically by the platform ADR (asynchronous-DRAM-refresh)
 mechanism at a power loss event. Support for "locked" DIMMs is included
 to prevent namespaces from surfacing when the namespace label data area
 is locked. Finally, fixes for various reported deadlocks and crashes,
 also tagged for -stable.
 
 * ACPI / nfit driver updates: General updates of the nfit driver to add
 DSM command overrides, ACPI 6.1 health state flags support, DSM payload
 debug available by default, and various fixes.
 
 Acknowledgements that came after the branch was pushed:
 
 commmit 565851c972 "device-dax: fix sysfs attribute deadlock"
 Tested-by: Yi Zhang <yizhan@redhat.com>
 
 commit 23f4984483 "libnvdimm: rework region badblocks clearing"
 Tested-by: Toshi Kani <toshi.kani@hpe.com>
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Merge tag 'libnvdimm-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "The bulk of this has been in multiple -next releases. There were a few
  late breaking fixes and small features that got added in the last
  couple days, but the whole set has received a build success
  notification from the kbuild robot.

  Change summary:

   - Region media error reporting: A libnvdimm region device is the
     parent to one or more namespaces. To date, media errors have been
     reported via the "badblocks" attribute attached to pmem block
     devices for namespaces in "raw" or "memory" mode. Given that
     namespaces can be in "device-dax" or "btt-sector" mode this new
     interface reports media errors generically, i.e. independent of
     namespace modes or state.

     This subsequently allows userspace tooling to craft "ACPI 6.1
     Section 9.20.7.6 Function Index 4 - Clear Uncorrectable Error"
     requests and submit them via the ioctl path for NVDIMM root bus
     devices.

   - Introduce 'struct dax_device' and 'struct dax_operations': Prompted
     by a request from Linus and feedback from Christoph this allows for
     dax capable drivers to publish their own custom dax operations.
     This fixes the broken assumption that all dax operations are
     related to a persistent memory device, and makes it easier for
     other architectures and platforms to add customized persistent
     memory support.

   - 'libnvdimm' core updates: A new "deep_flush" sysfs attribute is
     available for storage appliance applications to manually trigger
     memory controllers to drain write-pending buffers that would
     otherwise be flushed automatically by the platform ADR
     (asynchronous-DRAM-refresh) mechanism at a power loss event.
     Support for "locked" DIMMs is included to prevent namespaces from
     surfacing when the namespace label data area is locked. Finally,
     fixes for various reported deadlocks and crashes, also tagged for
     -stable.

   - ACPI / nfit driver updates: General updates of the nfit driver to
     add DSM command overrides, ACPI 6.1 health state flags support, DSM
     payload debug available by default, and various fixes.

  Acknowledgements that came after the branch was pushed:

   - commmit 565851c972 "device-dax: fix sysfs attribute deadlock":
     Tested-by: Yi Zhang <yizhan@redhat.com>

   - commit 23f4984483 "libnvdimm: rework region badblocks clearing"
     Tested-by: Toshi Kani <toshi.kani@hpe.com>"

* tag 'libnvdimm-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (52 commits)
  libnvdimm, pfn: fix 'npfns' vs section alignment
  libnvdimm: handle locked label storage areas
  libnvdimm: convert NDD_ flags to use bitops, introduce NDD_LOCKED
  brd: fix uninitialized use of brd->dax_dev
  block, dax: use correct format string in bdev_dax_supported
  device-dax: fix sysfs attribute deadlock
  libnvdimm: restore "libnvdimm: band aid btt vs clear poison locking"
  libnvdimm: fix nvdimm_bus_lock() vs device_lock() ordering
  libnvdimm: rework region badblocks clearing
  acpi, nfit: kill ACPI_NFIT_DEBUG
  libnvdimm: fix clear length of nvdimm_forget_poison()
  libnvdimm, pmem: fix a NULL pointer BUG in nd_pmem_notify
  libnvdimm, region: sysfs trigger for nvdimm_flush()
  libnvdimm: fix phys_addr for nvdimm_clear_poison
  x86, dax, pmem: remove indirection around memcpy_from_pmem()
  block: remove block_device_operations ->direct_access()
  block, dax: convert bdev_dax_supported() to dax_direct_access()
  filesystem-dax: convert to dax_direct_access()
  Revert "block: use DAX for partition table reads"
  ext2, ext4, xfs: retrieve dax_device for iomap operations
  ...
2017-05-05 18:49:20 -07:00
Eric Biggers
d9b9f8d5a8 ext4: clean up ext4_match() and callers
When ext4 encryption was originally merged, we were encrypting the
user-specified filename in ext4_match(), introducing a lot of additional
complexity into ext4_match() and its callers.  This has since been
changed to encrypt the filename earlier, so we can remove the gunk
that's no longer needed.  This more or less reverts ext4_search_dir()
and ext4_find_dest_de() to the way they were in the v4.0 kernel.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:44:40 -04:00
Eric Biggers
067d1023b6 ext4: switch to using fscrypt_match_name()
Switch ext4 directory searches to use the fscrypt_match_name() helper
function.  There should be no functional change.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:44:38 -04:00
Eric Biggers
6b06cdee81 fscrypt: avoid collisions when presenting long encrypted filenames
When accessing an encrypted directory without the key, userspace must
operate on filenames derived from the ciphertext names, which contain
arbitrary bytes.  Since we must support filenames as long as NAME_MAX,
we can't always just base64-encode the ciphertext, since that may make
it too long.  Currently, this is solved by presenting long names in an
abbreviated form containing any needed filesystem-specific hashes (e.g.
to identify a directory block), then the last 16 bytes of ciphertext.
This needs to be sufficient to identify the actual name on lookup.

However, there is a bug.  It seems to have been assumed that due to the
use of a CBC (ciphertext block chaining)-based encryption mode, the last
16 bytes (i.e. the AES block size) of ciphertext would depend on the
full plaintext, preventing collisions.  However, we actually use CBC
with ciphertext stealing (CTS), which handles the last two blocks
specially, causing them to appear "flipped".  Thus, it's actually the
second-to-last block which depends on the full plaintext.

This caused long filenames that differ only near the end of their
plaintexts to, when observed without the key, point to the wrong inode
and be undeletable.  For example, with ext4:

    # echo pass | e4crypt add_key -p 16 edir/
    # seq -f "edir/abcdefghijklmnopqrstuvwxyz012345%.0f" 100000 | xargs touch
    # find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l
    100000
    # sync
    # echo 3 > /proc/sys/vm/drop_caches
    # keyctl new_session
    # find edir/ -type f | xargs stat -c %i | sort | uniq | wc -l
    2004
    # rm -rf edir/
    rm: cannot remove 'edir/_A7nNFi3rhkEQlJ6P,hdzluhODKOeWx5V': Structure needs cleaning
    ...

To fix this, when presenting long encrypted filenames, encode the
second-to-last block of ciphertext rather than the last 16 bytes.

Although it would be nice to solve this without depending on a specific
encryption mode, that would mean doing a cryptographic hash like SHA-256
which would be much less efficient.  This way is sufficient for now, and
it's still compatible with encryption modes like HEH which are strong
pseudorandom permutations.  Also, changing the presented names is still
allowed at any time because they are only provided to allow applications
to do things like delete encrypted directories.  They're not designed to
be used to persistently identify files --- which would be hard to do
anyway, given that they're encrypted after all.

For ease of backports, this patch only makes the minimal fix to both
ext4 and f2fs.  It leaves ubifs as-is, since ubifs doesn't compare the
ciphertext block yet.  Follow-on patches will clean things up properly
and make the filesystems use a shared helper function.

Fixes: 5de0b4d0cd ("ext4 crypto: simplify and speed up filename encryption")
Reported-by: Gwendal Grignou <gwendal@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:44:36 -04:00
Eric Biggers
8c68084bff ext4: remove "nokey" check from ext4_lookup()
Now that fscrypt_has_permitted_context() correctly handles the case
where we have the key for the parent directory but not the child, we
don't need to try to work around this in ext4_lookup().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:44:33 -04:00
Jan Kara
00473374b7 ext4: mark superblock writes synchronous for nobarrier mounts
Commit b685d3d65a "block: treat REQ_FUA and REQ_PREFLUSH as
synchronous" removed REQ_SYNC flag from WRITE_FUA implementation.
generic_make_request_checks() however strips REQ_FUA flag from a bio
when the storage doesn't report volatile write cache and thus write
effectively becomes asynchronous which can lead to performance
regressions. This affects superblock writes for ext4. Fix the problem
by marking superblock writes always as synchronous.

Fixes: b685d3d65a
CC: linux-ext4@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 10:58:03 -04:00
Linus Torvalds
a3719f34fd Merge branch 'generic' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull quota, reiserfs, udf and ext2 updates from Jan Kara:
 "The branch contains changes to quota code so that it does not modify
  persistent flags in inode->i_flags (it was the only place in kernel
  doing that) and handle it inside filesystem's quotaon/off handlers
  instead.

  The branch also contains two UDF cleanups, a couple of reiserfs fixes
  and one fix for ext2 quota locking"

* 'generic' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  ext4: Improve comments in ext4_quota_{on|off}()
  udf: use kmap_atomic for memcpy copying
  udf: use octal for permissions
  quota: Remove dquot_quotactl_ops
  reiserfs: Remove i_attrs_to_sd_attrs()
  reiserfs: Remove useless setting of i_flags
  jfs: Remove jfs_get_inode_flags()
  ext2: Remove ext2_get_inode_flags()
  ext4: Remove ext4_get_inode_flags()
  quota: Stop setting IMMUTABLE and NOATIME flags on quota files
  jfs: Set flags on quota files directly
  ext2: Set flags on quota files directly
  reiserfs: Set flags on quota files directly
  ext4: Set flags on quota files directly
  reiserfs: Protect dquot_writeback_dquots() by s_umount semaphore
  reiserfs: Make cancel_old_flush() reliable
  ext2: Call dquot_writeback_dquots() with s_umount held
  reiserfs: avoid a -Wmaybe-uninitialized warning
2017-05-03 11:35:47 -07:00
Eric Biggers
aa1dca3bd9 ext4: inherit encryption xattr before other xattrs
When using both encryption and SELinux (or another feature that requires
an xattr per file) on a filesystem with 256-byte inodes, each file's
xattrs usually spill into an external xattr block.  Currently, the
xattrs are inherited in the order ACL, security, then encryption.
Therefore, if spillage occurs, the encryption xattr will always end up
in the external block.  This is not ideal because the encryption xattrs
contain a nonce, so they will always be unique and will prevent the
external xattr blocks from being deduplicated.

To improve the situation, change the inheritance order to encryption,
ACL, then security.  This gives the encryption xattr a better chance to
be stored in-inode, allowing the other xattr(s) to be deduplicated.

Note that it may be better for userspace to format the filesystem with
512-byte inodes in this case.  However, it's not the default.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-02 00:49:54 -04:00
Theodore Ts'o
72d622b422 ext4: replace BUG_ON with WARN_ONCE in ext4_end_bio()
Add fallback code and a WARN_ONCE() call instead of a BUG_ON() in
the ext4_end_bio() function.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 20:08:05 -04:00
Jan Kara
dddbd6ac8f ext4: avoid unnecessary transaction stalls during writeback
Currently ext4_writepages() submits all pages with transaction started.
When no page needs block allocation or extent conversion we can submit
all dirty pages in the inode while holding a single transaction handle
and when device is congested this can take significant amount of time.
Thus ext4_writepages() can block transaction commits for extended
periods of time.

Take for example a simple benchmark simulating PostgreSQL database
(pgioperf in mmtest). The benchmark runs 16 processes doing random reads
from a huge file, one process doing random writes to the huge file, and
one process doing sequential writes to a small files and frequently
running fsync. With unpatched kernel transaction commits take on average
~18s with standard deviation of ~41s, top 5 commit times are:

274.466639s, 126.467347s, 86.992429s, 34.351563s, 31.517653s.

After this patch transaction commits take on average 0.1s with standard
deviation of 0.15s, top 5 commit times are:

0.563792s, 0.519980s, 0.509841s, 0.471700s, 0.469899s

[ Modified so we use an explicit do_map flag instead of relying on
  io_end not being allocated, the since io_end->inode is needed for I/O
  error handling. -- tytso ]

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 18:29:10 -04:00
Andrew Perepechko
85c8f176a6 ext4: preload block group descriptors
With enabled meta_bg option block group descriptors
reading IO is not sequential and requires optimization.

Signed-off-by: Andrew Perepechko <andrew.perepechko@seagate.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 00:46:35 -04:00
Eric Biggers
1a20a63084 ext4: make ext4_shutdown() static
Make the ext4_shutdown() function static, as suggested by running sparse
('make C=2 fs/ext4/').  This was the only such warning in fs/ext4/.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 00:40:44 -04:00
Darrick J. Wong
0c9ec4beec ext4: support GETFSMAP ioctls
Support the GETFSMAP ioctls so that we can use the xfs free space
management tools to probe ext4 as well.  Note that this is a partial
implementation -- we only report fixed-location metadata and free space;
everything else is reported as "unknown".

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 00:36:53 -04:00
Eric Biggers
7b4cc9787f ext4: evict inline data when writing to memory map
Currently the case of writing via mmap to a file with inline data is not
handled.  This is maybe a rare case since it requires a writable memory
map of a very small file, but it is trivial to trigger with on
inline_data filesystem, and it causes the
'BUG_ON(ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA));' in
ext4_writepages() to be hit:

    mkfs.ext4 -O inline_data /dev/vdb
    mount /dev/vdb /mnt
    xfs_io -f /mnt/file \
	-c 'pwrite 0 1' \
	-c 'mmap -w 0 1m' \
	-c 'mwrite 0 1' \
	-c 'fsync'

	kernel BUG at fs/ext4/inode.c:2723!
	invalid opcode: 0000 [#1] SMP
	CPU: 1 PID: 2532 Comm: xfs_io Not tainted 4.11.0-rc1-xfstests-00301-g071d9acf3d1f #633
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-20170228_101828-anatol 04/01/2014
	task: ffff88003d3a8040 task.stack: ffffc90000300000
	RIP: 0010:ext4_writepages+0xc89/0xf8a
	RSP: 0018:ffffc90000303ca0 EFLAGS: 00010283
	RAX: 0000028410000000 RBX: ffff8800383fa3b0 RCX: ffffffff812afcdc
	RDX: 00000a9d00000246 RSI: ffffffff81e660e0 RDI: 0000000000000246
	RBP: ffffc90000303dc0 R08: 0000000000000002 R09: 869618e8f99b4fa5
	R10: 00000000852287a2 R11: 00000000a03b49f4 R12: ffff88003808e698
	R13: 0000000000000000 R14: 7fffffffffffffff R15: 7fffffffffffffff
	FS:  00007fd3e53094c0(0000) GS:ffff88003e400000(0000) knlGS:0000000000000000
	CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
	CR2: 00007fd3e4c51000 CR3: 000000003d554000 CR4: 00000000003406e0
	Call Trace:
	 ? _raw_spin_unlock+0x27/0x2a
	 ? kvm_clock_read+0x1e/0x20
	 do_writepages+0x23/0x2c
	 ? do_writepages+0x23/0x2c
	 __filemap_fdatawrite_range+0x80/0x87
	 filemap_write_and_wait_range+0x67/0x8c
	 ext4_sync_file+0x20e/0x472
	 vfs_fsync_range+0x8e/0x9f
	 ? syscall_trace_enter+0x25b/0x2d0
	 vfs_fsync+0x1c/0x1e
	 do_fsync+0x31/0x4a
	 SyS_fsync+0x10/0x14
	 do_syscall_64+0x69/0x131
	 entry_SYSCALL64_slow_path+0x25/0x25

We could try to be smart and keep the inline data in this case, or at
least support delayed allocation when allocating the block, but these
solutions would be more complicated and don't seem worthwhile given how
rare this case seems to be.  So just fix the bug by calling
ext4_convert_inline_data() when we're asked to make a page writable, so
that any inline data gets evicted, with the block allocated immediately.

Reported-by: Nick Alcock <nick.alcock@oracle.com>
Cc: stable@vger.kernel.org
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 00:10:50 -04:00
Eric Biggers
6ba644b9fd ext4: remove ext4_xattr_check_entry()
ext4_xattr_check_entry() was redundant with validation of the full xattr
entries list in ext4_xattr_check_entries(), which all callers also did.
ext4_xattr_check_entry() also didn't actually do correct validation;
specifically, it never checked that the value doesn't overlap the xattr
names, nor did it account for padding when checking whether the xattr
value overflows the available space.  So remove it to eliminate any
potential confusion.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-30 00:01:02 -04:00
Eric Biggers
2c4f992337 ext4: rename ext4_xattr_check_names() to ext4_xattr_check_entries()
ext4_xattr_check_names() actually validates both the xattr names and
values, not just the names.  So rename it to ext4_xattr_check_entries()
to avoid confusion.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-29 23:56:52 -04:00
Eric Biggers
ba7ea1d8f4 ext4: merge ext4_xattr_list() into ext4_listxattr()
There's no difference between ext4_xattr_list() and ext4_listxattr(), so
merge them together and just have ext4_listxattr().  Some years ago they
took different arguments, but that's no longer the case.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-29 23:53:17 -04:00
Eric Biggers
d600618673 ext4: constify static data that is never modified
Constify static data in ext4 that is never (intentionally) modified so
that it is placed in .rodata and benefits from memory protection.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-29 23:47:50 -04:00
Eric Biggers
1bc0af600b ext4: trim return value and 'dir' argument from ext4_insert_dentry()
In the initial implementation of ext4 encryption, the filename was
encrypted in ext4_insert_dentry(), which could fail and also required
access to the 'dir' inode.  Since then ext4 filename encryption has been
changed to encrypt the filename earlier, so we can revert the additions
to ext4_insert_dentry().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-04-29 23:27:26 -04:00
Dan Williams
fa5d932c32 ext2, ext4, xfs: retrieve dax_device for iomap operations
In preparation for converting fs/dax.c to use dax_direct_access()
instead of bdev_direct_access(), add the plumbing to retrieve the
dax_device associated with a given block_device.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-25 13:20:46 -07:00