Eric Lee / smarc-fsl-linux-kernel

05 Apr, 2016

1 commit

  • 09cbfeaf1   mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros ... Browse Code »

    PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
    ago with promise that one day it will be possible to implement page
    cache with bigger chunks than PAGE_SIZE.

    This promise never materialized. And unlikely will.

    We have many places where PAGE_CACHE_SIZE assumed to be equal to
    PAGE_SIZE. And it's constant source of confusion on whether
    PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
    especially on the border between fs and mm.

    Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
    breakage to be doable.

    Let's stop pretending that pages in page cache are special. They are
    not.

    The changes are pretty straight-forward:

    - << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> ;

    - >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> ;

    - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

    - page_cache_get() -> get_page();

    - page_cache_release() -> put_page();

    This patch contains automated changes generated with coccinelle using
    script below. For some reason, coccinelle doesn't patch header files.
    I've called spatch for them manually.

    The only adjustment after coccinelle is revert of changes to
    PAGE_CAHCE_ALIGN definition: we are going to drop it later.

    There are few places in the code where coccinelle didn't reach. I'll
    fix them manually in a separate patch. Comments and documentation also
    will be addressed with the separate patch.

    virtual patch

    @@
    expression E;
    @@
    - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
    + E

    @@
    expression E;
    @@
    - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
    + E

    @@
    @@
    - PAGE_CACHE_SHIFT
    + PAGE_SHIFT

    @@
    @@
    - PAGE_CACHE_SIZE
    + PAGE_SIZE

    @@
    @@
    - PAGE_CACHE_MASK
    + PAGE_MASK

    @@
    expression E;
    @@
    - PAGE_CACHE_ALIGN(E)
    + PAGE_ALIGN(E)

    @@
    expression E;
    @@
    - page_cache_get(E)
    + get_page(E)

    @@
    expression E;
    @@
    - page_cache_release(E)
    + put_page(E)

    Signed-off-by: Kirill A. Shutemov
    Acked-by: Michal Hocko
    Signed-off-by: Linus Torvalds

    Kirill A. Shutemov
     

09 Jan, 2016

1 commit

07 Nov, 2015

1 commit

  • c62d25556   mm, fs: introduce mapping_gfp_constraint() ... Browse Code »

    There are many places which use mapping_gfp_mask to restrict a more
    generic gfp mask which would be used for allocations which are not
    directly related to the page cache but they are performed in the same
    context.

    Let's introduce a helper function which makes the restriction explicit and
    easier to track. This patch doesn't introduce any functional changes.

    [akpm@linux-foundation.org: coding-style fixes]
    Signed-off-by: Michal Hocko
    Suggested-by: Andrew Morton
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Michal Hocko
     

24 Jan, 2014

1 commit

  • 2252b62a5   logfs: check for the return value after calling find_or_create_page() ... Browse Code »

    In get_mapping_page(), after calling find_or_create_page(), the return
    value should be checked.

    This patch has been provided:
    http://www.spinics.net/lists/linux-fsdevel/msg66948.html but not been
    applied now.

    Signed-off-by: Younger Liu
    Cc: Younger Liu
    Cc: Vyacheslav Dubeyko
    Reviewed-by: Prasad Joshi
    Cc: Jörn Engel
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Younger Liu
     

22 May, 2013

1 commit

  • d47992f86   mm: change invalidatepage prototype to accept length ... Browse Code »

    Currently there is no way to truncate partial page where the end
    truncate point is not at the end of the page. This is because it was not
    needed and the functionality was enough for file system truncate
    operation to work properly. However more file systems now support punch
    hole feature and it can benefit from mm supporting truncating page just
    up to the certain point.

    Specifically, with this functionality truncate_inode_pages_range() can
    be changed so it supports truncating partial page at the end of the
    range (currently it will BUG_ON() if 'end' is not at the end of the
    page).

    This commit changes the invalidatepage() address space operation
    prototype to accept range to be invalidated and update all the instances
    for it.

    We also change the block_invalidatepage() in the same way and actually
    make a use of the new length argument implementing range invalidation.

    Actual file system implementations will follow except the file systems
    where the changes are really simple and should not change the behaviour
    in any way .Implementation for truncate_page_range() which will be able
    to accept page unaligned ranges will follow as well.

    Signed-off-by: Lukas Czerner
    Cc: Andrew Morton
    Cc: Hugh Dickins

    Lukas Czerner
     

02 Apr, 2012

1 commit

  • d2dcd9083   logfs: destroy the reserved inodes while unmounting ... Browse Code »

    We were assuming that the evict_inode() would never be called on
    reserved inodes. However, (after the commit 8e22c1a4e logfs: get rid
    of magical inodes) while unmounting the file system, in put_super, we
    call iput() on all of the reserved inodes.

    The following simple test used to cause a kernel panic on LogFS:

    1. Mount a LogFS file system on /mnt

    2. Create a file
    $ touch /mnt/a

    3. Try to unmount the FS
    $ umount /mnt

    The simple fix would be to drop the assumption and properly destroy
    the reserved inodes.

    Signed-off-by: Prasad Joshi

    Prasad Joshi
     

20 Mar, 2012

1 commit

28 Jan, 2012

2 commits

10 Aug, 2010

1 commit

05 May, 2010

1 commit

22 Apr, 2010

1 commit

  • 255f41c59   Merge git://git.kernel.org/pub/scm/linux/kernel/git/joern/logfs ... Browse Code »

    * git://git.kernel.org/pub/scm/linux/kernel/git/joern/logfs:
    [LogFS] Split large truncated into smaller chunks
    [LogFS] Set s_bdi
    [LogFS] Prevent mempool_destroy NULL pointer dereference
    [LogFS] Move assertion
    [LogFS] Plug 8 byte information leak
    [LogFS] Prevent memory corruption on large deletes
    [LogFS] Remove unused method

    Fix trivial conflict with added header includes in fs/logfs/super.c

    Linus Torvalds
     

15 Apr, 2010

1 commit

05 Apr, 2010

1 commit

31 Mar, 2010

1 commit

30 Mar, 2010

1 commit

  • 5a0e3ad6a   include cleanup: Update gfp.h and slab.h includes to prepare for breaking implic… ... Browse Code »

    …it slab.h inclusion from percpu.h

    percpu.h is included by sched.h and module.h and thus ends up being
    included when building most .c files. percpu.h includes slab.h which
    in turn includes gfp.h making everything defined by the two files
    universally available and complicating inclusion dependencies.

    percpu.h -> slab.h dependency is about to be removed. Prepare for
    this change by updating users of gfp and slab facilities include those
    headers directly instead of assuming availability. As this conversion
    needs to touch large number of source files, the following script is
    used as the basis of conversion.

    http://userweb.kernel.org/~tj/misc/slabh-sweep.py

    The script does the followings.

    * Scan files for gfp and slab usages and update includes such that
    only the necessary includes are there. ie. if only gfp is used,
    gfp.h, if slab is used, slab.h.

    * When the script inserts a new include, it looks at the include
    blocks and try to put the new include such that its order conforms
    to its surrounding. It's put in the include block which contains
    core kernel includes, in the same order that the rest are ordered -
    alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
    doesn't seem to be any matching order.

    * If the script can't find a place to put a new include (mostly
    because the file doesn't have fitting include block), it prints out
    an error message indicating which .h file needs to be added to the
    file.

    The conversion was done in the following steps.

    1. The initial automatic conversion of all .c files updated slightly
    over 4000 files, deleting around 700 includes and adding ~480 gfp.h
    and ~3000 slab.h inclusions. The script emitted errors for ~400
    files.

    2. Each error was manually checked. Some didn't need the inclusion,
    some needed manual addition while adding it to implementation .h or
    embedding .c file was more appropriate for others. This step added
    inclusions to around 150 files.

    3. The script was run again and the output was compared to the edits
    from #2 to make sure no file was left behind.

    4. Several build tests were done and a couple of problems were fixed.
    e.g. lib/decompress_*.c used malloc/free() wrappers around slab
    APIs requiring slab.h to be added manually.

    5. The script was run on all .h files but without automatically
    editing them as sprinkling gfp.h and slab.h inclusions around .h
    files could easily lead to inclusion dependency hell. Most gfp.h
    inclusion directives were ignored as stuff from gfp.h was usually
    wildly available and often used in preprocessor macros. Each
    slab.h inclusion directive was examined and added manually as
    necessary.

    6. percpu.h was updated not to include slab.h.

    7. Build test were done on the following configurations and failures
    were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
    distributed build env didn't work with gcov compiles) and a few
    more options had to be turned off depending on archs to make things
    build (like ipr on powerpc/64 which failed due to missing writeq).

    * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
    * powerpc and powerpc64 SMP allmodconfig
    * sparc and sparc64 SMP allmodconfig
    * ia64 SMP allmodconfig
    * s390 SMP allmodconfig
    * alpha SMP allmodconfig
    * um on x86_64 SMP allmodconfig

    8. percpu.h modifications were reverted so that it could be applied as
    a separate patch and serve as bisection point.

    Given the fact that I had only a couple of failures from tests on step
    6, I'm fairly confident about the coverage of this conversion patch.
    If there is a breakage, it's likely to be something in one of the arch
    headers which should be easily discoverable easily on most builds of
    the specific arch.

    Signed-off-by: Tejun Heo <tj@kernel.org>
    Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
    Cc: Ingo Molnar <mingo@redhat.com>
    Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

    Tejun Heo
     

29 Mar, 2010

1 commit

28 Mar, 2010

1 commit

  • 81def6b98   Simplify and fix pad_wbuf ... Browse Code »

    A comment in the old code read:
    /* The math in this function can surely use some love */

    And indeed it did. In the case that area->a_used_bytes is exactly
    4096 bytes below segment size it fell apart. pad_wbuf is now split
    into two helpers that are significantly less complicated.

    Signed-off-by: Joern Engel

    Joern Engel
     

05 Mar, 2010

2 commits

  • c6d383014   [LogFS] Only write journal if dirty ... Browse Code »

    This prevents unnecessary journal writes. More importantly it prevents
    an oops due to a journal write on failed mount.

    Joern Engel
     
  • 9421502b4   [LogFS] Fix bdev erases ... Browse Code »

    Erases for block devices were always just emulated by writing 0xff.
    Some time back the write was removed and only the page cache was
    changed to 0xff. Superficialy a good idea with two problems:
    1. Touching the page cache isn't necessary either.
    2. However, writing out 0xff _is_ necessary for the journal. As the
    journal is scanned linearly, an old non-overwritten commit entry
    can be used on next mount and cause havoc.

    This should fix both aspects.

    Joern Engel
     

21 Nov, 2009

1 commit