1. 12 Jun, 2018 1 commit
    • Kees Cook's avatar
      treewide: Use array_size() in vzalloc() · fad953ce
      Kees Cook authored
      The vzalloc() function has no 2-factor argument form, so multiplication
      factors need to be wrapped in array_size(). This patch replaces cases of:
      
              vzalloc(a * b)
      
      with:
              vzalloc(array_size(a, b))
      
      as well as handling cases of:
      
              vzalloc(a * b * c)
      
      with:
      
              vzalloc(array3_size(a, b, c))
      
      This does, however, attempt to ignore constant size factors like:
      
              vzalloc(4 * 1024)
      
      though any constants defined via macros get caught up in the conversion.
      
      Any factors with a sizeof() of "unsigned char", "char", and "u8" were
      dropped, since they're redundant.
      
      The Coccinelle script used for this was:
      
      // Fix redundant parens around sizeof().
      @@
      type TYPE;
      expression THING, E;
      @@
      
      (
        vzalloc(
      -	(sizeof(TYPE)) * E
      +	sizeof(TYPE) * E
        , ...)
      |
        vzalloc(
      -	(sizeof(THING)) * E
      +	sizeof(THING) * E
        , ...)
      )
      
      // Drop single-byte sizes and redundant parens.
      @@
      expression COUNT;
      typedef u8;
      typedef __u8;
      @@
      
      (
        vzalloc(
      -	sizeof(u8) * (COUNT)
      +	COUNT
        , ...)
      |
        vzalloc(
      -	sizeof(__u8) * (COUNT)
      +	COUNT
        , ...)
      |
        vzalloc(
      -	sizeof(char) * (COUNT)
      +	COUNT
        , ...)
      |
        vzalloc(
      -	sizeof(unsigned char) * (COUNT)
      +	COUNT
        , ...)
      |
        vzalloc(
      -	sizeof(u8) * COUNT
      +	COUNT
        , ...)
      |
        vzalloc(
      -	sizeof(__u8) * COUNT
      +	COUNT
        , ...)
      |
        vzalloc(
      -	sizeof(char) * COUNT
      +	COUNT
        , ...)
      |
        vzalloc(
      -	sizeof(unsigned char) * COUNT
      +	COUNT
        , ...)
      )
      
      // 2-factor product with sizeof(type/expression) and identifier or constant.
      @@
      type TYPE;
      expression THING;
      identifier COUNT_ID;
      constant COUNT_CONST;
      @@
      
      (
        vzalloc(
      -	sizeof(TYPE) * (COUNT_ID)
      +	array_size(COUNT_ID, sizeof(TYPE))
        , ...)
      |
        vzalloc(
      -	sizeof(TYPE) * COUNT_ID
      +	array_size(COUNT_ID, sizeof(TYPE))
        , ...)
      |
        vzalloc(
      -	sizeof(TYPE) * (COUNT_CONST)
      +	array_size(COUNT_CONST, sizeof(TYPE))
        , ...)
      |
        vzalloc(
      -	sizeof(TYPE) * COUNT_CONST
      +	array_size(COUNT_CONST, sizeof(TYPE))
        , ...)
      |
        vzalloc(
      -	sizeof(THING) * (COUNT_ID)
      +	array_size(COUNT_ID, sizeof(THING))
        , ...)
      |
        vzalloc(
      -	sizeof(THING) * COUNT_ID
      +	array_size(COUNT_ID, sizeof(THING))
        , ...)
      |
        vzalloc(
      -	sizeof(THING) * (COUNT_CONST)
      +	array_size(COUNT_CONST, sizeof(THING))
        , ...)
      |
        vzalloc(
      -	sizeof(THING) * COUNT_CONST
      +	array_size(COUNT_CONST, sizeof(THING))
        , ...)
      )
      
      // 2-factor product, only identifiers.
      @@
      identifier SIZE, COUNT;
      @@
      
        vzalloc(
      -	SIZE * COUNT
      +	array_size(COUNT, SIZE)
        , ...)
      
      // 3-factor product with 1 sizeof(type) or sizeof(expression), with
      // redundant parens removed.
      @@
      expression THING;
      identifier STRIDE, COUNT;
      type TYPE;
      @@
      
      (
        vzalloc(
      -	sizeof(TYPE) * (COUNT) * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        vzalloc(
      -	sizeof(TYPE) * (COUNT) * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        vzalloc(
      -	sizeof(TYPE) * COUNT * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        vzalloc(
      -	sizeof(TYPE) * COUNT * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        vzalloc(
      -	sizeof(THING) * (COUNT) * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      |
        vzalloc(
      -	sizeof(THING) * (COUNT) * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      |
        vzalloc(
      -	sizeof(THING) * COUNT * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      |
        vzalloc(
      -	sizeof(THING) * COUNT * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      )
      
      // 3-factor product with 2 sizeof(variable), with redundant parens removed.
      @@
      expression THING1, THING2;
      identifier COUNT;
      type TYPE1, TYPE2;
      @@
      
      (
        vzalloc(
      -	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
        , ...)
      |
        vzalloc(
      -	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
        , ...)
      |
        vzalloc(
      -	sizeof(THING1) * sizeof(THING2) * COUNT
      +	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
        , ...)
      |
        vzalloc(
      -	sizeof(THING1) * sizeof(THING2) * (COUNT)
      +	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
        , ...)
      |
        vzalloc(
      -	sizeof(TYPE1) * sizeof(THING2) * COUNT
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
        , ...)
      |
        vzalloc(
      -	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
        , ...)
      )
      
      // 3-factor product, only identifiers, with redundant parens removed.
      @@
      identifier STRIDE, SIZE, COUNT;
      @@
      
      (
        vzalloc(
      -	(COUNT) * STRIDE * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vzalloc(
      -	COUNT * (STRIDE) * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vzalloc(
      -	COUNT * STRIDE * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vzalloc(
      -	(COUNT) * (STRIDE) * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vzalloc(
      -	COUNT * (STRIDE) * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vzalloc(
      -	(COUNT) * STRIDE * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vzalloc(
      -	(COUNT) * (STRIDE) * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        vzalloc(
      -	COUNT * STRIDE * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      )
      
      // Any remaining multi-factor products, first at least 3-factor products
      // when they're not all constants...
      @@
      expression E1, E2, E3;
      constant C1, C2, C3;
      @@
      
      (
        vzalloc(C1 * C2 * C3, ...)
      |
        vzalloc(
      -	E1 * E2 * E3
      +	array3_size(E1, E2, E3)
        , ...)
      )
      
      // And then all remaining 2 factors products when they're not all constants.
      @@
      expression E1, E2;
      constant C1, C2;
      @@
      
      (
        vzalloc(C1 * C2, ...)
      |
        vzalloc(
      -	E1 * E2
      +	array_size(E1, E2)
        , ...)
      )
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      fad953ce
  2. 06 May, 2014 4 commits
  3. 08 Aug, 2013 1 commit
    • Jeff Mahoney's avatar
      reiserfs: locking, handle nested locks properly · 278f6679
      Jeff Mahoney authored
      The reiserfs write lock replaced the BKL and uses similar semantics.
      
      Frederic's locking code makes a distinction between when the lock is nested
      and when it's being acquired/released, but I don't think that's the right
      distinction to make.
      
      The right distinction is between the lock being released at end-of-use and
      the lock being released for a schedule. The unlock should return the depth
      and the lock should restore it, rather than the other way around as it is now.
      
      This patch implements that and adds a number of places where the lock
      should be dropped.
      Signed-off-by: default avatarJeff Mahoney <jeffm@suse.com>
      278f6679
  4. 01 Jun, 2012 1 commit
  5. 21 Mar, 2012 2 commits
  6. 15 Sep, 2011 1 commit
  7. 26 Jul, 2011 1 commit
  8. 14 Sep, 2009 1 commit
    • Frederic Weisbecker's avatar
      reiserfs: kill-the-BKL · 8ebc4232
      Frederic Weisbecker authored
      This patch is an attempt to remove the Bkl based locking scheme from
      reiserfs and is intended.
      
      It is a bit inspired from an old attempt by Peter Zijlstra:
      
         http://lkml.indiana.edu/hypermail/linux/kernel/0704.2/2174.html
      
      The bkl is heavily used in this filesystem to prevent from
      concurrent write accesses on the filesystem.
      
      Reiserfs makes a deep use of the specific properties of the Bkl:
      
      - It can be acqquired recursively by a same task
      - It is released on the schedule() calls and reacquired when schedule() returns
      
      The two properties above are a roadmap for the reiserfs write locking so it's
      very hard to simply replace it with a common mutex.
      
      - We need a recursive-able locking unless we want to restructure several blocks
        of the code.
      - We need to identify the sites where the bkl was implictly relaxed
        (schedule, wait, sync, etc...) so that we can in turn release and
        reacquire our new lock explicitly.
        Such implicit releases of the lock are often required to let other
        resources producer/consumer do their job or we can suffer unexpected
        starvations or deadlocks.
      
      So the new lock that replaces the bkl here is a per superblock mutex with a
      specific property: it can be acquired recursively by a same task, like the
      bkl.
      
      For such purpose, we integrate a lock owner and a lock depth field on the
      superblock information structure.
      
      The first axis on this patch is to turn reiserfs_write_(un)lock() function
      into a wrapper to manage this mutex. Also some explicit calls to
      lock_kernel() have been converted to reiserfs_write_lock() helpers.
      
      The second axis is to find the important blocking sites (schedule...(),
      wait_on_buffer(), sync_dirty_buffer(), etc...) and then apply an explicit
      release of the write lock on these locations before blocking. Then we can
      safely wait for those who can give us resources or those who need some.
      Typically this is a fight between the current writer, the reiserfs workqueue
      (aka the async commiter) and the pdflush threads.
      
      The third axis is a consequence of the second. The write lock is usually
      on top of a lock dependency chain which can include the journal lock, the
      flush lock or the commit lock. So it's dangerous to release and trying to
      reacquire the write lock while we still hold other locks.
      
      This is fine with the bkl:
      
            T1                       T2
      
      lock_kernel()
          mutex_lock(A)
          unlock_kernel()
          // do something
                                  lock_kernel()
                                      mutex_lock(A) -> already locked by T1
                                      schedule() (and then unlock_kernel())
          lock_kernel()
          mutex_unlock(A)
          ....
      
      This is not fine with a mutex:
      
            T1                       T2
      
      mutex_lock(write)
          mutex_lock(A)
          mutex_unlock(write)
          // do something
                                 mutex_lock(write)
                                    mutex_lock(A) -> already locked by T1
                                    schedule()
      
          mutex_lock(write) -> already locked by T2
          deadlock
      
      The solution in this patch is to provide a helper which releases the write
      lock and sleep a bit if we can't lock a mutex that depend on it. It's another
      simulation of the bkl behaviour.
      
      The last axis is to locate the fs callbacks that are called with the bkl held,
      according to Documentation/filesystem/Locking.
      
      Those are:
      
      - reiserfs_remount
      - reiserfs_fill_super
      - reiserfs_put_super
      
      Reiserfs didn't need to explicitly lock because of the context of these callbacks.
      But now we must take care of that with the new locking.
      
      After this patch, reiserfs suffers from a slight performance regression (for now).
      On UP, a high volume write with dd reports an average of 27 MB/s instead
      of 30 MB/s without the patch applied.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Reviewed-by: default avatarIngo Molnar <mingo@elte.hu>
      Cc: Jeff Mahoney <jeffm@suse.com>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: Bron Gondwana <brong@fastmail.fm>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      LKML-Reference: <1239070789-13354-1-git-send-email-fweisbec@gmail.com>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      8ebc4232
  9. 24 Jun, 2009 1 commit
  10. 30 Mar, 2009 1 commit
  11. 19 Oct, 2007 3 commits
  12. 08 May, 2007 1 commit
  13. 01 Oct, 2006 3 commits
    • Jeff Mahoney's avatar
      [PATCH] reiserfs: on-demand bitmap loading · 5065227b
      Jeff Mahoney authored
      This is the patch the three previous ones have been leading up to.
      
      It changes the behavior of ReiserFS from loading and caching all the bitmaps
      as special, to treating the bitmaps like any other bit of metadata and just
      letting the system-wide caches figure out what to hang on to.
      
      Buffer heads are allocated on the fly, so there is no need to retain pointers
      to all of them.  The caching of the metadata occurs when the data is read and
      updated, and is considered invalid and uncached until then.
      
      I needed to remove the vs-4040 check for performing a duplicate operation on a
      particular bit.  The reason is that while the other sites for working with
      bitmaps are allowed to schedule, is_reusable() is called from do_balance(),
      which will panic if a schedule occurs in certain places.
      
      The benefit of on-demand bitmaps clearly outweighs a sanity check that depends
      on a compile-time option that is discouraged.
      
      [akpm@osdl.org: warning fix]
      Signed-off-by: default avatarJeff Mahoney <jeffm@suse.com>
      Cc: <reiserfs-dev@namesys.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      5065227b
    • Jeff Mahoney's avatar
      [PATCH] reiserfs: reorganize bitmap loading functions · 6f01046b
      Jeff Mahoney authored
      This patch moves the bitmap loading code from super.c to bitmap.c
      
      The code is also restructured somewhat.  The only difference between new
      format bitmaps and old format bitmaps is where they are.  That's a two liner
      before loading the block to use the correct one.  There's no need for an
      entirely separate code path.
      
      The load path is generally the same, with the pattern being to throw out a
      bunch of requests and then wait for them, then cache the metadata from the
      contents.
      
      Again, like the previous patches, the purpose is to set up for later ones.
      
      Update: There was a bug in the previously posted version of this that resulted
      in corruption.  The problem was that bitmap 0 on new format file systems must
      be treated specially, and wasn't.  A stupid bug with an easy fix.
      
      This is hopefully the last fix for the disaster that is the reiserfs bitmap
      patch set.
      
      If a bitmap block was full, first_zero_hint would end up at zero since it
      would never be changed from it's zeroed out value.  This just sets it
      beyond the end of the bitmap block.  If any bits are freed, it will be
      reset to a valid bit.  When info->free_count = 0, then we already know it's
      full.
      Signed-off-by: default avatarJeff Mahoney <jeffm@suse.com>
      Cc: <reiserfs-dev@namesys.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      6f01046b
    • Jeff Mahoney's avatar
      [PATCH] reiserfs: clean up bitmap block buffer head references · 0b3dc17b
      Jeff Mahoney authored
      Similar to the SB_JOURNAL cleanup that was accepted a while ago, this patch
      uses a temporary variable for buffer head references from the bitmap info
      array.
      
      This makes the code much more readable in some areas.
      
      It also uses proper reference counting, doing a get_bh() after using the
      pointer from the array and brelse()'ing it later.  This may seem silly, but a
      later patch will replace the simple temporary variables with an actual read,
      so the reference freeing will be used then.
      Signed-off-by: default avatarJeff Mahoney <jeffm@suse.com>
      Cc: <reiserfs-dev@namesys.com>
      Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      0b3dc17b
  14. 13 Jul, 2005 1 commit
    • Linus Torvalds's avatar
      reiserfs: run scripts/Lindent on reiserfs code · bd4c625c
      Linus Torvalds authored
      This was a pure indentation change, using:
      
      	scripts/Lindent fs/reiserfs/*.c include/linux/reiserfs_*.h
      
      to make reiserfs match the regular Linux indentation style.  As Jeff
      Mahoney <jeffm@suse.com> writes:
      
       The ReiserFS code is a mix of a number of different coding styles, sometimes
       different even from line-to-line. Since the code has been relatively stable
       for quite some time and there are few outstanding patches to be applied, it
       is time to reformat the code to conform to the Linux style standard outlined
       in Documentation/CodingStyle.
      
       This patch contains the result of running scripts/Lindent against
       fs/reiserfs/*.c and include/linux/reiserfs_*.h. There are places where the
       code can be made to look better, but I'd rather keep those patches separate
       so that there isn't a subtle by-hand hand accident in the middle of a huge
       patch. To be clear: This patch is reformatting *only*.
      
       A number of patches may follow that continue to make the code more consistent
       with the Linux coding style.
      
       Hans wasn't particularly enthusiastic about these patches, but said he
       wouldn't really oppose them either.
      Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
      bd4c625c
  15. 16 Apr, 2005 1 commit
    • Linus Torvalds's avatar
      Linux-2.6.12-rc2 · 1da177e4
      Linus Torvalds authored
      Initial git repository build. I'm not bothering with the full history,
      even though we have it. We can create a separate "historical" git
      archive of that later if we want to, and in the meantime it's about
      3.2GB when imported into git - space that would just make the early
      git days unnecessarily complicated, when we don't have a lot of good
      infrastructure for it.
      
      Let it rip!
      1da177e4