1. 16 11月, 2017 3 次提交
  2. 09 11月, 2017 1 次提交
  3. 02 11月, 2017 1 次提交
    • G
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman 提交于
      Many source files in the tree are missing licensing information, which
      makes it harder for compliance tools to determine the correct license.
      
      By default all files without license information are under the default
      license of the kernel, which is GPL version 2.
      
      Update the files which contain no license information with the 'GPL-2.0'
      SPDX license identifier.  The SPDX identifier is a legally binding
      shorthand, which can be used instead of the full boiler plate text.
      
      This patch is based on work done by Thomas Gleixner and Kate Stewart and
      Philippe Ombredanne.
      
      How this work was done:
      
      Patches were generated and checked against linux-4.14-rc6 for a subset of
      the use cases:
       - file had no licensing information it it.
       - file was a */uapi/* one with no licensing information in it,
       - file was a */uapi/* one with existing licensing information,
      
      Further patches will be generated in subsequent months to fix up cases
      where non-standard license headers were used, and references to license
      had to be inferred by heuristics based on keywords.
      
      The analysis to determine which SPDX License Identifier to be applied to
      a file was done in a spreadsheet of side by side results from of the
      output of two independent scanners (ScanCode & Windriver) producing SPDX
      tag:value files created by Philippe Ombredanne.  Philippe prepared the
      base worksheet, and did an initial spot review of a few 1000 files.
      
      The 4.13 kernel was the starting point of the analysis with 60,537 files
      assessed.  Kate Stewart did a file by file comparison of the scanner
      results in the spreadsheet to determine which SPDX license identifier(s)
      to be applied to the file. She confirmed any determination that was not
      immediately clear with lawyers working with the Linux Foundation.
      
      Criteria used to select files for SPDX license identifier tagging was:
       - Files considered eligible had to be source code files.
       - Make and config files were included as candidates if they contained >5
         lines of source
       - File already had some variant of a license header in it (even if <5
         lines).
      
      All documentation files were explicitly excluded.
      
      The following heuristics were used to determine which SPDX license
      identifiers to apply.
      
       - when both scanners couldn't find any license traces, file was
         considered to have no license information in it, and the top level
         COPYING file license applied.
      
         For non */uapi/* files that summary was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0                                              11139
      
         and resulted in the first patch in this series.
      
         If that file was a */uapi/* path one, it was "GPL-2.0 WITH
         Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|-------
         GPL-2.0 WITH Linux-syscall-note                        930
      
         and resulted in the second patch in this series.
      
       - if a file had some form of licensing information in it, and was one
         of the */uapi/* ones, it was denoted with the Linux-syscall-note if
         any GPL family license was found in the file or had no licensing in
         it (per prior point).  Results summary:
      
         SPDX license identifier                            # files
         ---------------------------------------------------|------
         GPL-2.0 WITH Linux-syscall-note                       270
         GPL-2.0+ WITH Linux-syscall-note                      169
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
         LGPL-2.1+ WITH Linux-syscall-note                      15
         GPL-1.0+ WITH Linux-syscall-note                       14
         ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
         LGPL-2.0+ WITH Linux-syscall-note                       4
         LGPL-2.1 WITH Linux-syscall-note                        3
         ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
         ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1
      
         and that resulted in the third patch in this series.
      
       - when the two scanners agreed on the detected license(s), that became
         the concluded license(s).
      
       - when there was disagreement between the two scanners (one detected a
         license but the other didn't, or they both detected different
         licenses) a manual inspection of the file occurred.
      
       - In most cases a manual inspection of the information in the file
         resulted in a clear resolution of the license that should apply (and
         which scanner probably needed to revisit its heuristics).
      
       - When it was not immediately clear, the license identifier was
         confirmed with lawyers working with the Linux Foundation.
      
       - If there was any question as to the appropriate license identifier,
         the file was flagged for further research and to be revisited later
         in time.
      
      In total, over 70 hours of logged manual review was done on the
      spreadsheet to determine the SPDX license identifiers to apply to the
      source files by Kate, Philippe, Thomas and, in some cases, confirmation
      by lawyers working with the Linux Foundation.
      
      Kate also obtained a third independent scan of the 4.13 code base from
      FOSSology, and compared selected files where the other two scanners
      disagreed against that SPDX file, to see if there was new insights.  The
      Windriver scanner is based on an older version of FOSSology in part, so
      they are related.
      
      Thomas did random spot checks in about 500 files from the spreadsheets
      for the uapi headers and agreed with SPDX license identifier in the
      files he inspected. For the non-uapi files Thomas did random spot checks
      in about 15000 files.
      
      In initial set of patches against 4.14-rc6, 3 files were found to have
      copy/paste license identifier errors, and have been fixed to reflect the
      correct identifier.
      
      Additionally Philippe spent 10 hours this week doing a detailed manual
      inspection and review of the 12,461 patched files from the initial patch
      version early this week with:
       - a full scancode scan run, collecting the matched texts, detected
         license ids and scores
       - reviewing anything where there was a license detected (about 500+
         files) to ensure that the applied SPDX license was correct
       - reviewing anything where there was no detection but the patch license
         was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
         SPDX license was correct
      
      This produced a worksheet with 20 files needing minor correction.  This
      worksheet was then exported into 3 different .csv files for the
      different types of files to be modified.
      
      These .csv files were then reviewed by Greg.  Thomas wrote a script to
      parse the csv files and add the proper SPDX tag to the file, in the
      format that the file expected.  This script was further refined by Greg
      based on the output to detect more types of files automatically and to
      distinguish between header and source .c files (which need different
      comment types.)  Finally Greg ran the script using the .csv files to
      generate the patches.
      Reviewed-by: NKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: NPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      b2441318
  4. 29 10月, 2017 1 次提交
  5. 19 10月, 2017 12 次提交
  6. 13 10月, 2017 2 次提交
  7. 12 10月, 2017 3 次提交
    • R
      ext4: add sanity check for encryption + DAX · 7d3e06a8
      Ross Zwisler 提交于
      We prevent DAX from being used on inodes which are using ext4's built in
      encryption via a check in ext4_set_inode_flags().  We do have what appears
      to be an unsafe transition of S_DAX in ext4_set_context(), though, where
      S_DAX can get disabled without us doing a proper writeback + invalidate.
      
      There are also issues with mm-level races when changing the value of S_DAX,
      as well as issues with the VM_MIXEDMAP flag:
      
      https://www.spinics.net/lists/linux-xfs/msg09859.html
      
      I actually think we are safe in this case because of the following:
      
      1) You can't encrypt an existing file.  Encryption can only be set on an
      empty directory, with new inodes in that directory being created with
      encryption turned on, so I don't think it's possible to turn encryption on
      for a file that has open DAX mmaps or outstanding I/Os.
      
      2) There is no way to turn encryption off on a given file.  Once an inode
      is encrypted, it stays encrypted for the life of that inode, so we don't
      have to worry about the case where we turn encryption off and S_DAX
      suddenly turns on.
      
      3) The only way we end up in ext4_set_context() to turn on encryption is
      when we are creating a new file in the encrypted directory.  This happens
      as part of ext4_create() before the inode has been allowed to do any I/O.
      Here's the call tree:
      
       ext4_create()
         __ext4_new_inode()
      	 ext4_set_inode_flags() // sets S_DAX
      	 fscrypt_inherit_context()
      		fscrypt_get_encryption_info();
      		ext4_set_context() // sets EXT4_INODE_ENCRYPT, clears S_DAX
      
      So, I actually think it's safe to transition S_DAX in ext4_set_context()
      without any locking, writebacks or invalidations.  I've added a
      WARN_ON_ONCE() sanity check to make sure that we are notified if we ever
      encounter a case where we are encrypting an inode that already has data,
      in which case we need to add code to safely transition S_DAX.
      Signed-off-by: NRoss Zwisler <ross.zwisler@linux.intel.com>
      Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
      Reviewed-by: NJan Kara <jack@suse.cz>
      7d3e06a8
    • R
      ext4: prevent data corruption with journaling + DAX · e9072d85
      Ross Zwisler 提交于
      The current code has the potential for data corruption when changing an
      inode's journaling mode, as that can result in a subsequent unsafe change
      in S_DAX.
      
      I've captured an instance of this data corruption in the following fstest:
      
      https://patchwork.kernel.org/patch/9948377/
      
      Prevent this data corruption from happening by disallowing changes to the
      journaling mode if the '-o dax' mount option was used.  This means that for
      a given filesystem we could have a mix of inodes using either DAX or
      data journaling, but whatever state the inodes are in will be held for the
      duration of the mount.
      Signed-off-by: NRoss Zwisler <ross.zwisler@linux.intel.com>
      Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
      Reviewed-by: NJan Kara <jack@suse.cz>
      Cc: stable@vger.kernel.org
      e9072d85
    • R
      ext4: prevent data corruption with inline data + DAX · 559db4c6
      Ross Zwisler 提交于
      If an inode has inline data it is currently prevented from using DAX by a
      check in ext4_set_inode_flags().  When the inode grows inline data via
      ext4_create_inline_data() or removes its inline data via
      ext4_destroy_inline_data_nolock(), the value of S_DAX can change.
      
      Currently these changes are unsafe because we don't hold off page faults
      and I/O, write back dirty radix tree entries and invalidate all mappings.
      There are also issues with mm-level races when changing the value of S_DAX,
      as well as issues with the VM_MIXEDMAP flag:
      
      https://www.spinics.net/lists/linux-xfs/msg09859.html
      
      The unsafe transition of S_DAX can reliably cause data corruption, as shown
      by the following fstest:
      
      https://patchwork.kernel.org/patch/9948381/
      
      Fix this issue by preventing the DAX mount option from being used on
      filesystems that were created to support inline data.  Inline data is an
      option given to mkfs.ext4.
      Signed-off-by: NRoss Zwisler <ross.zwisler@linux.intel.com>
      Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
      Reviewed-by: NJan Kara <jack@suse.cz>
      CC: stable@vger.kernel.org
      559db4c6
  8. 07 10月, 2017 1 次提交
    • T
      ext4: fix interaction between i_size, fallocate, and delalloc after a crash · 51e3ae81
      Theodore Ts'o 提交于
      If there are pending writes subject to delayed allocation, then i_size
      will show size after the writes have completed, while i_disksize
      contains the value of i_size on the disk (since the writes have not
      been persisted to disk).
      
      If fallocate(2) is called with the FALLOC_FL_KEEP_SIZE flag, either
      with or without the FALLOC_FL_ZERO_RANGE flag set, and the new size
      after the fallocate(2) is between i_size and i_disksize, then after a
      crash, if a journal commit has resulted in the changes made by the
      fallocate() call to be persisted after a crash, but the delayed
      allocation write has not resolved itself, i_size would not be updated,
      and this would cause the following e2fsck complaint:
      
      Inode 12, end of extent exceeds allowed value
      	(logical block 33, physical block 33441, len 7)
      
      This can only take place on a sparse file, where the fallocate(2) call
      is allocating blocks in a range which is before a pending delayed
      allocation write which is extending i_size.  Since this situation is
      quite rare, and the window in which the crash must take place is
      typically < 30 seconds, in practice this condition will rarely happen.
      
      Nevertheless, it can be triggered in testing, and in particular by
      xfstests generic/456.
      Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
      Reported-by: NAmir Goldstein <amir73il@gmail.com>
      Cc: stable@vger.kernel.org
      51e3ae81
  9. 02 10月, 2017 4 次提交
  10. 07 9月, 2017 5 次提交
    • J
      mm: remove nr_pages argument from pagevec_lookup{,_range}() · 397162ff
      Jan Kara 提交于
      All users of pagevec_lookup() and pagevec_lookup_range() now pass
      PAGEVEC_SIZE as a desired number of pages.
      
      Just drop the argument.
      
      Link: http://lkml.kernel.org/r/20170726114704.7626-11-jack@suse.czSigned-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      397162ff
    • J
      ext4: use pagevec_lookup_range() in writeback code · 2b85a617
      Jan Kara 提交于
      Both occurences of pagevec_lookup() actually want only pages from a
      given range.  Use pagevec_lookup_range() for the lookup.
      
      Link: http://lkml.kernel.org/r/20170726114704.7626-7-jack@suse.czSigned-off-by: NJan Kara <jack@suse.cz>
      Cc: "Theodore Ts'o" <tytso@mit.edu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      2b85a617
    • J
      ext4: use pagevec_lookup_range() in ext4_find_unwritten_pgoff() · dec0da7b
      Jan Kara 提交于
      Use pagevec_lookup_range() in ext4_find_unwritten_pgoff() since we are
      interested only in pages in the given range.  Simplify the logic as a
      result of not getting pages out of range and index getting automatically
      advanced.
      
      Link: http://lkml.kernel.org/r/20170726114704.7626-6-jack@suse.czSigned-off-by: NJan Kara <jack@suse.cz>
      Cc: "Theodore Ts'o" <tytso@mit.edu>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      dec0da7b
    • J
      mm: make pagevec_lookup() update index · d72dc8a2
      Jan Kara 提交于
      Make pagevec_lookup() (and underlying find_get_pages()) update index to
      the next page where iteration should continue.  Most callers want this
      and also pagevec_lookup_tag() already does this.
      
      Link: http://lkml.kernel.org/r/20170726114704.7626-3-jack@suse.czSigned-off-by: NJan Kara <jack@suse.cz>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d72dc8a2
    • R
      dax: use common 4k zero page for dax mmap reads · 91d25ba8
      Ross Zwisler 提交于
      When servicing mmap() reads from file holes the current DAX code
      allocates a page cache page of all zeroes and places the struct page
      pointer in the mapping->page_tree radix tree.
      
      This has three major drawbacks:
      
      1) It consumes memory unnecessarily. For every 4k page that is read via
         a DAX mmap() over a hole, we allocate a new page cache page. This
         means that if you read 1GiB worth of pages, you end up using 1GiB of
         zeroed memory. This is easily visible by looking at the overall
         memory consumption of the system or by looking at /proc/[pid]/smaps:
      
      	7f62e72b3000-7f63272b3000 rw-s 00000000 103:00 12   /root/dax/data
      	Size:            1048576 kB
      	Rss:             1048576 kB
      	Pss:             1048576 kB
      	Shared_Clean:          0 kB
      	Shared_Dirty:          0 kB
      	Private_Clean:   1048576 kB
      	Private_Dirty:         0 kB
      	Referenced:      1048576 kB
      	Anonymous:             0 kB
      	LazyFree:              0 kB
      	AnonHugePages:         0 kB
      	ShmemPmdMapped:        0 kB
      	Shared_Hugetlb:        0 kB
      	Private_Hugetlb:       0 kB
      	Swap:                  0 kB
      	SwapPss:               0 kB
      	KernelPageSize:        4 kB
      	MMUPageSize:           4 kB
      	Locked:                0 kB
      
      2) It is slower than using a common zero page because each page fault
         has more work to do. Instead of just inserting a common zero page we
         have to allocate a page cache page, zero it, and then insert it. Here
         are the average latencies of dax_load_hole() as measured by ftrace on
         a random test box:
      
          Old method, using zeroed page cache pages:	3.4 us
          New method, using the common 4k zero page:	0.8 us
      
         This was the average latency over 1 GiB of sequential reads done by
         this simple fio script:
      
           [global]
           size=1G
           filename=/root/dax/data
           fallocate=none
           [io]
           rw=read
           ioengine=mmap
      
      3) The fact that we had to check for both DAX exceptional entries and
         for page cache pages in the radix tree made the DAX code more
         complex.
      
      Solve these issues by following the lead of the DAX PMD code and using a
      common 4k zero page instead.  As with the PMD code we will now insert a
      DAX exceptional entry into the radix tree instead of a struct page
      pointer which allows us to remove all the special casing in the DAX
      code.
      
      Note that we do still pretty aggressively check for regular pages in the
      DAX radix tree, especially where we take action based on the bits set in
      the page.  If we ever find a regular page in our radix tree now that
      most likely means that someone besides DAX is inserting pages (which has
      happened lots of times in the past), and we want to find that out early
      and fail loudly.
      
      This solution also removes the extra memory consumption.  Here is that
      same /proc/[pid]/smaps after 1GiB of reading from a hole with the new
      code:
      
      	7f2054a74000-7f2094a74000 rw-s 00000000 103:00 12   /root/dax/data
      	Size:            1048576 kB
      	Rss:                   0 kB
      	Pss:                   0 kB
      	Shared_Clean:          0 kB
      	Shared_Dirty:          0 kB
      	Private_Clean:         0 kB
      	Private_Dirty:         0 kB
      	Referenced:            0 kB
      	Anonymous:             0 kB
      	LazyFree:              0 kB
      	AnonHugePages:         0 kB
      	ShmemPmdMapped:        0 kB
      	Shared_Hugetlb:        0 kB
      	Private_Hugetlb:       0 kB
      	Swap:                  0 kB
      	SwapPss:               0 kB
      	KernelPageSize:        4 kB
      	MMUPageSize:           4 kB
      	Locked:                0 kB
      
      Overall system memory consumption is similarly improved.
      
      Another major change is that we remove dax_pfn_mkwrite() from our fault
      flow, and instead rely on the page fault itself to make the PTE dirty
      and writeable.  The following description from the patch adding the
      vm_insert_mixed_mkwrite() call explains this a little more:
      
         "To be able to use the common 4k zero page in DAX we need to have our
          PTE fault path look more like our PMD fault path where a PTE entry
          can be marked as dirty and writeable as it is first inserted rather
          than waiting for a follow-up dax_pfn_mkwrite() =>
          finish_mkwrite_fault() call.
      
          Right now we can rely on having a dax_pfn_mkwrite() call because we
          can distinguish between these two cases in do_wp_page():
      
                  case 1: 4k zero page => writable DAX storage
                  case 2: read-only DAX storage => writeable DAX storage
      
          This distinction is made by via vm_normal_page(). vm_normal_page()
          returns false for the common 4k zero page, though, just as it does
          for DAX ptes. Instead of special casing the DAX + 4k zero page case
          we will simplify our DAX PTE page fault sequence so that it matches
          our DAX PMD sequence, and get rid of the dax_pfn_mkwrite() helper.
          We will instead use dax_iomap_fault() to handle write-protection
          faults.
      
          This means that insert_pfn() needs to follow the lead of
          insert_pfn_pmd() and allow us to pass in a 'mkwrite' flag. If
          'mkwrite' is set insert_pfn() will do the work that was previously
          done by wp_page_reuse() as part of the dax_pfn_mkwrite() call path"
      
      Link: http://lkml.kernel.org/r/20170724170616.25810-4-ross.zwisler@linux.intel.comSigned-off-by: NRoss Zwisler <ross.zwisler@linux.intel.com>
      Reviewed-by: NJan Kara <jack@suse.cz>
      Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
      Cc: "Theodore Ts'o" <tytso@mit.edu>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: Andreas Dilger <adilger.kernel@dilger.ca>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Dan Williams <dan.j.williams@intel.com>
      Cc: Dave Chinner <david@fromorbit.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Matthew Wilcox <mawilcox@microsoft.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      91d25ba8
  11. 06 9月, 2017 1 次提交
  12. 05 9月, 2017 1 次提交
  13. 01 9月, 2017 1 次提交
  14. 31 8月, 2017 1 次提交
    • A
      ext4: avoid Y2038 overflow in recently_deleted() · b5f51573
      Andreas Dilger 提交于
      Avoid a 32-bit time overflow in recently_deleted() since i_dtime
      (inode deletion time) is stored only as a 32-bit value on disk.
      Since i_dtime isn't used for much beyond a boolean value in e2fsck
      and is otherwise only used in this function in the kernel, there is
      no benefit to use more space in the inode for this field on disk.
      
      Instead, compare only the relative deletion time with the low
      32 bits of the time using the newly-added time_before32() helper,
      which is similar to time_before() and time_after() for jiffies.
      
      Increase RECENTCY_DIRTY to 300s based on Ted's comments about
      usage experience at Google.
      Signed-off-by: NAndreas Dilger <adilger@dilger.ca>
      Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
      Reviewed-by: NArnd Bergmann <arnd@arndb.de>
      b5f51573
  15. 25 8月, 2017 3 次提交
    • R
      ext4: fix fault handling when mounted with -o dax,ro · fd96b8da
      Randy Dodgen 提交于
      If an ext4 filesystem is mounted with both the DAX and read-only
      options, executables on that filesystem will fail to start (claiming
      'Segmentation fault') due to the fault handler returning
      VM_FAULT_SIGBUS.
      
      This is due to the DAX fault handler (see ext4_dax_huge_fault)
      attempting to write to the journal when FAULT_FLAG_WRITE is set. This is
      the wrong behavior for write faults which will lead to a COW page; in
      particular, this fails for readonly mounts.
      
      This change avoids journal writes for faults that are expected to COW.
      
      It might be the case that this could be better handled in
      ext4_iomap_begin / ext4_iomap_end (called via iomap_ops inside
      dax_iomap_fault). These is some overlap already (e.g. grabbing journal
      handles).
      Signed-off-by: NRandy Dodgen <dodgen@google.com>
      Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
      Reviewed-by: NJan Kara <jack@suse.cz>
      Reviewed-by: NRoss Zwisler <ross.zwisler@linux.intel.com>
      fd96b8da
    • Z
      ext4: fix quota inconsistency during orphan cleanup for read-only mounts · 95f1fda4
      zhangyi (F) 提交于
      Quota does not get enabled for read-only mounts if filesystem
      has quota feature, so that quotas cannot updated during orphan
      cleanup, which will lead to quota inconsistency.
      
      This patch turn on quotas during orphan cleanup for this case,
      make sure quotas can be updated correctly.
      Reported-by: NJan Kara <jack@suse.cz>
      Signed-off-by: Nzhangyi (F) <yi.zhang@huawei.com>
      Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
      Reviewed-by: NJan Kara <jack@suse.cz>
      Cc: stable@vger.kernel.org # 3.18+
      95f1fda4
    • Z
      ext4: fix incorrect quotaoff if the quota feature is enabled · b0a5a958
      zhangyi (F) 提交于
      Current ext4 quota should always "usage enabled" if the
      quota feautre is enabled. But in ext4_orphan_cleanup(), it
      turn quotas off directly (used for the older journaled
      quota), so we cannot turn it on again via "quotaon" unless
      umount and remount ext4.
      
      Simple reproduce:
      
        mkfs.ext4 -O project,quota /dev/vdb1
        mount -o prjquota /dev/vdb1 /mnt
        chattr -p 123 /mnt
        chattr +P /mnt
        touch /mnt/aa /mnt/bb
        exec 100<>/mnt/aa
        rm -f /mnt/aa
        sync
        echo c > /proc/sysrq-trigger
      
        #reboot and mount
        mount -o prjquota /dev/vdb1 /mnt
        #query status
        quotaon -Ppv /dev/vdb1
        #output
        quotaon: Cannot find mountpoint for device /dev/vdb1
        quotaon: No correct mountpoint specified.
      
      This patch add check for journaled quotas to avoid incorrect
      quotaoff when ext4 has quota feautre.
      Signed-off-by: Nzhangyi (F) <yi.zhang@huawei.com>
      Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
      Reviewed-by: NJan Kara <jack@suse.cz>
      Cc: stable@vger.kernel.org # 3.18
      b0a5a958