1. 18 Dec, 2017 1 commit
    • Theodore Ts'o's avatar
      ext4: fix up remaining files with SPDX cleanups · f5166768
      Theodore Ts'o authored
      A number of ext4 source files were skipped due because their copyright
      permission statements didn't match the expected text used by the
      automated conversion utilities.  I've added SPDX tags for the rest.
      While looking at some of these files, I've noticed that we have quite
      a bit of variation on the licenses that were used --- in particular
      some of the Red Hat licenses on the jbd2 files use a GPL2+ license,
      and we have some files that have a LGPL-2.1 license (which was quite
      I've not attempted to do any license changes.  Even if it is perfectly
      legal to relicense to GPL 2.0-only for consistency's sake, that should
      be done with ext4 developer community discussion.
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
  2. 10 Mar, 2016 1 commit
  3. 01 Sep, 2014 1 commit
  4. 21 Apr, 2014 1 commit
    • Lukas Czerner's avatar
      ext4: rename uninitialized extents to unwritten · 556615dc
      Lukas Czerner authored
      Currently in ext4 there is quite a mess when it comes to naming
      unwritten extents. Sometimes we call it uninitialized and sometimes we
      refer to it as unwritten.
      The right name for the extent which has been allocated but does not
      contain any written data is _unwritten_. Other file systems are
      using this name consistently, even the buffer head state refers to it as
      unwritten. We need to fix this confusion in ext4.
      This commit changes every reference to an uninitialized extent (meaning
      allocated but unwritten) to unwritten extent. This includes comments,
      function names and variable names. It even covers abbreviation of the
      word uninitialized (such as uninit) and some misspellings.
      This commit does not change any of the code paths at all. This has been
      confirmed by comparing md5sums of the assembly code of each object file
      after all the function names were stripped from it.
      Signed-off-by: default avatarLukas Czerner <lczerner@redhat.com>
      Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
  5. 28 Aug, 2013 1 commit
    • Zheng Liu's avatar
      ext4: isolate ext4_extents.h file · d7b2a00c
      Zheng Liu authored
      After applied the commit (4a092d73
      ), we have reduced the number of
      source files that need to #include ext4_extents.h.  But we can do
      This commit defines ext4_zeroout_es() in extents.c and move
      EXT_MAX_BLOCKS into ext4.h in order not to include ext4_extents.h in
      indirect.c and ioctl.c.  Meanwhile we just need to include this file in
      extent_status.c when ES_AGGRESSIVE_TEST is defined.  Otherwise, this
      commit removes a duplicated declaration in trace/events/ext4.h.
      After applied this patch, we just need to include ext4_extents.h file
      in {super,migrate,move_extents,extents}.c, and it is easy for us to
      define a new extent disk layout.
      Signed-off-by: default avatarZheng Liu <wenqing.lz@taobao.com>
      Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
  6. 19 Apr, 2013 1 commit
  7. 18 Feb, 2013 1 commit
  8. 28 Nov, 2012 2 commits
    • Theodore Ts'o's avatar
      ext4: rationalize ext4_extents.h inclusion · 4a092d73
      Theodore Ts'o authored
      Previously, ext4_extents.h was being included at the end of ext4.h,
      which was bad for a number of reasons: (a) it was not being included
      in the expected place, and (b) it caused the header to be included
      multiple times.  There were #ifdef's to prevent this from causing any
      problems, but it still was unnecessary.
      By moving the function declarations that were in ext4_extents.h to
      ext4.h, which is standard practice for where the function declarations
      for the rest of ext4.h can be found, we can remove ext4_extents.h from
      being included in ext4.h at all, and then we can only include
      ext4_extents.h where it is needed in ext4's source files.
      It should be possible to move a few more things into ext4.h, and
      further reduce the number of source files that need to #include
      ext4_extents.h, but that's a cleanup for another day.
      Reported-by: default avatarSachin Kamat <sachin.kamat@linaro.org>
      Reported-by: default avatarWei Yongjun <weiyj.lk@gmail.com>
      Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
    • Lukas Czerner's avatar
      ext4: prevent race while walking extent tree for fiemap · 91dd8c11
      Lukas Czerner authored
      Currently ext4_ext_walk_space() only takes i_data_sem for read when
      searching for the extent at given block with ext4_ext_find_extent().
      Then it drops the lock and the extent tree can be changed at will.
      However later on we're searching for the 'next' extent, but the extent
      tree might already have changed, so the information might not be
      In fact we can hit BUG_ON(end <= start) if the extent got inserted into
      the tree after the one we found and before the block we were searching
      for. This has been reproduced by running xfstests 225 in loop on s390x
      architecture, but theoretically we could hit this on any other
      architecture as well, but probably not as often.
      Moreover the extent currently in delayed allocation might be allocated
      after we search the extent tree and before we search extent status tree
      delayed buffers resulting in those delayed buffers being completely
      missed, even though completely written and allocated.
      We fix all those problems in several steps:
       1. remove unnecessary callback indirection
       2. rename functions
              ext4_ext_walk_space -> ext4_fill_fiemap_extents
              ext4_ext_fiemap_cb -> ext4_find_delayed_extent
       3. move fiemap_fill_next_extent() into ext4_fill_fiemap_extents()
       4. hold the i_data_sem for:
       5. call fiemap_fill_next_extent after releasing the i_data_sem
       6. move path reinitialization into the critical section.
      Signed-off-by: default avatarLukas Czerner <lczerner@redhat.com>
      Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
  9. 09 Nov, 2012 1 commit
  10. 29 Apr, 2012 2 commits
  11. 20 Mar, 2012 1 commit
  12. 09 Sep, 2011 1 commit
  13. 06 Jun, 2011 2 commits
    • Lukas Czerner's avatar
      ext4: use FIEMAP_EXTENT_LAST flag for last extent in fiemap · c03f8aa9
      Lukas Czerner authored
      Currently we are not marking the extent as the last one
      (FIEMAP_EXTENT_LAST) if there is a hole at the end of the file. This is
      because we just do not check for it right now and continue searching for
      next extent. But at the point we hit the hole at the end of the file, it
      is too late.
      This commit adds check for the allocated block in subsequent extent and
      if there is no more extents (block = EXT_MAX_BLOCKS) just flag the
      current one as the last one.
      This behaviour has been spotted unintentionally by 252 xfstest, when the
      test hangs out, because of wrong loop condition. However on other
      filesystems (like xfs) it will exit anyway, because we notice the last
      extent flag and exit.
      With this patch xfstest 252 does not hang anymore, ext4 fiemap
      implementation still reports bad extent type in some cases, however
      this seems to be different issue.
      Signed-off-by: default avatarLukas Czerner <lczerner@redhat.com>
      Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
    • Lukas Czerner's avatar
      ext4: Fix max file size and logical block counting of extent format file · f17722f9
      Lukas Czerner authored
      Kazuya Mio reported that he was able to hit BUG_ON(next == lblock)
      in ext4_ext_put_gap_in_cache() while creating a sparse file in extent
      format and fill the tail of file up to its end. We will hit the BUG_ON
      when we write the last block (2^32-1) into the sparse file.
      The root cause of the problem lies in the fact that we specifically set
      s_maxbytes so that block at s_maxbytes fit into on-disk extent format,
      which is 32 bit long. However, we are not storing start and end block
      number, but rather start block number and length in blocks. It means
      that in order to cover extent from 0 to EXT_MAX_BLOCK we need
      EXT_MAX_BLOCK+1 to fit into len (because we counting block 0 as well) -
      and it does not.
      The only way to fix it without changing the meaning of the struct
      ext4_extent members is, as Kazuya Mio suggested, to lower s_maxbytes
      by one fs block so we can cover the whole extent we can get by the
      on-disk extent format.
      Also in many places EXT_MAX_BLOCK is used as length instead of maximum
      logical block number as the name suggests, it is all a bit messy. So
      this commit renames it to EXT_MAX_BLOCKS and change its usage in some
      places to actually be maximum number of blocks in the extent.
      The bug which this commit fixes can be reproduced as follows:
       dd if=/dev/zero of=/mnt/mp1/file bs=<blocksize> count=1 seek=$((2**32-2))
       dd if=/dev/zero of=/mnt/mp1/file bs=<blocksize> count=1 seek=$((2**32-1))
      Reported-by: default avatarKazuya Mio <k-mio@sx.jp.nec.com>
      Signed-off-by: default avatarLukas Czerner <lczerner@redhat.com>
      Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
  14. 10 Jan, 2011 2 commits
  15. 28 Oct, 2010 2 commits
  16. 01 Jan, 2010 1 commit
    • Theodore Ts'o's avatar
      ext4: Calculate metadata requirements more accurately · 9d0be502
      Theodore Ts'o authored
      In the past, ext4_calc_metadata_amount(), and its sub-functions
      ext4_ext_calc_metadata_amount() and ext4_indirect_calc_metadata_amount()
      badly over-estimated the number of metadata blocks that might be
      required for delayed allocation blocks.  This didn't matter as much
      when functions which managed the reserved metadata blocks were more
      aggressive about dropping reserved metadata blocks as delayed
      allocation blocks were written, but unfortunately they were too
      aggressive.  This was fixed in commit 0637c6f4
      , but as a result the
      over-estimation by ext4_calc_metadata_amount() would lead to reserving
      2-3 times the number of pending delayed allocation blocks as
      potentially required metadata blocks.  So if there are 1 megabytes of
      blocks which have been not yet been allocation, up to 3 megabytes of
      space would get reserved out of the user's quota and from the file
      system free space pool until all of the inode's data blocks have been
      This commit addresses this problem by much more accurately estimating
      the number of metadata blocks that will be required.  It will still
      somewhat over-estimate the number of blocks needed, since it must make
      a worst case estimate not knowing which physical blocks will be
      needed, but it is much more accurate than before.
      Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
  17. 28 Sep, 2009 1 commit
    • Mingming Cao's avatar
      ext4: Split uninitialized extents for direct I/O · 0031462b
      Mingming Cao authored
      When writing into an unitialized extent via direct I/O, and the direct
      I/O doesn't exactly cover the unitialized extent, split the extent
      into uninitialized and initialized extents before submitting the I/O.
      This avoids needing to deal with an ENOSPC error in the end_io
      callback that gets used for direct I/O.
      When the IO is complete, the written extent will be marked as initialized.
      Singed-Off-By: default avatarMingming Cao <cmm@us.ibm.com>
      Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
  18. 17 Sep, 2009 1 commit
  19. 18 Sep, 2009 1 commit
  20. 17 Jun, 2009 1 commit
  21. 27 Mar, 2009 1 commit
  22. 04 Nov, 2008 1 commit
  23. 07 Oct, 2008 1 commit
  24. 20 Aug, 2008 1 commit
  25. 14 Jul, 2008 1 commit
    • Mingming Cao's avatar
      ext4: delayed allocation ENOSPC handling · d2a17637
      Mingming Cao authored
      This patch does block reservation for delayed
      allocation, to avoid ENOSPC later at page flush time.
      Blocks(data and metadata) are reserved at da_write_begin()
      time, the freeblocks counter is updated by then, and the number of
      reserved blocks is store in per inode counter.
      At the writepage time, the unused reserved meta blocks are returned
      back. At unlink/truncate time, reserved blocks are properly released.
      Updated fix from  Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      to fix the oldallocator block reservation accounting with delalloc, added
      lock to guard the counters and also fix the reservation for meta blocks.
      Signed-off-by: default avatarAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Signed-off-by: default avatarMingming Cao <cmm@us.ibm.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
  26. 29 Apr, 2008 1 commit
  27. 25 Feb, 2008 1 commit
  28. 29 Jan, 2008 3 commits
  29. 17 Oct, 2007 2 commits
  30. 18 Jul, 2007 3 commits
    • Amit Arora's avatar
      Change on-disk format to support 2^15 uninitialized extents · 749269fa
      Amit Arora authored
      This change was suggested by Andreas Dilger. 
      This patch changes the EXT_MAX_LEN value and extent code which marks/checks
      uninitialized extents. With this change it will be possible to have
      initialized extents with 2^15 blocks (earlier the max blocks we could have
      was 2^15 - 1). This way we can have better extent-to-block alignment.
      Now, maximum number of blocks we can have in an initialized extent is 2^15
      and in an uninitialized extent is 2^15 - 1.
      Signed-off-by: default avatarAmit Arora <aarora@in.ibm.com>
    • Amit Arora's avatar
      write support for preallocated blocks · 56055d3a
      Amit Arora authored
      This patch adds write support to the uninitialized extents that get
      created when a preallocation is done using fallocate(). It takes care of
      splitting the extents into multiple (upto three) extents and merging the
      new split extents with neighbouring ones, if possible.
      Signed-off-by: default avatarAmit Arora <aarora@in.ibm.com>
    • Amit Arora's avatar
      fallocate support in ext4 · a2df2a63
      Amit Arora authored
      This patch implements ->fallocate() inode operation in ext4. With this
      patch users of ext4 file systems will be able to use fallocate() system
      call for persistent preallocation. Current implementation only supports
      preallocation for regular files (directories not supported as of date)
      with extent maps. This patch does not support block-mapped files currently.
      Only FALLOC_ALLOCATE and FALLOC_RESV_SPACE modes are being supported as of
      Signed-off-by: default avatarAmit Arora <aarora@in.ibm.com>