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
     

12 Apr, 2015

1 commit

26 Jan, 2015

1 commit

  • 5e993e253   ncpfs: get rid of d_validate() nonsense ... Browse Code »

    What we want is to have non-counting references to children in
    pagecache of parent directory, and avoid picking them after a child
    has been freed. Fine, so let's just have ->d_prune() clear
    parent's inode "has directory contents in page cache" flag.
    That way we don't need ->d_fsdata for storing offsets, so we can
    use it as a quick and dirty "is it referenced from page cache"
    flag.

    Signed-off-by: Al Viro

    Al Viro
     

04 Nov, 2014

1 commit

09 Oct, 2014

1 commit

04 Jan, 2012

1 commit

13 Jan, 2011

1 commit

07 Jan, 2011

3 commits

  • b5c84bf6f   fs: dcache remove dcache_lock ... Browse Code »

    dcache_lock no longer protects anything. remove it.

    Signed-off-by: Nick Piggin

    Nick Piggin
     
  • 2fd6b7f50   fs: dcache scale subdirs ... Browse Code »

    Protect d_subdirs and d_child with d_lock, except in filesystems that aren't
    using dcache_lock for these anyway (eg. using i_mutex).

    Note: if we change the locking rule in future so that ->d_child protection is
    provided only with ->d_parent->d_lock, it may allow us to reduce some locking.
    But it would be an exception to an otherwise regular locking scheme, so we'd
    have to see some good results. Probably not worthwhile.

    Signed-off-by: Nick Piggin

    Nick Piggin
     
  • 621e155a3   fs: change d_compare for rcu-walk ... Browse Code »

    Change d_compare so it may be called from lock-free RCU lookups. This
    does put significant restrictions on what may be done from the callback,
    however there don't seem to have been any problems with in-tree fses.
    If some strange use case pops up that _really_ cannot cope with the
    rcu-walk rules, we can just add new rcu-unaware callbacks, which would
    cause name lookup to drop out of rcu-walk mode.

    For in-tree filesystems, this is just a mechanical change.

    Signed-off-by: Nick Piggin

    Nick Piggin
     

05 Oct, 2010

1 commit

  • 2e54eb96e   BKL: Remove BKL from ncpfs ... Browse Code »

    Dozen of changes in ncpfs to provide some locking other than BKL.

    In readdir cache unlock and mark complete first page as last operation,
    so it can be used for synchronization, as code intended.

    When updating dentry name on case insensitive filesystems do at least
    some basic locking...

    Hold i_mutex when updating inode fields.

    Push some ncp_conn_is_valid down to ncp_request. Connection can become
    invalid at any moment, and fewer error code paths to test the better.

    Use i_size_{read,write} to modify file size.

    Set inode's backing_dev_info as ncpfs has its own special bdi.

    In ioctl unbreak ioctls invoked on filesystem mounted 'ro' - tests are
    for inode writeable or owner match, but were turned to filesystem
    writeable and inode writeable or owner match. Also collect all permission
    checks in single place.

    Add some locking, and remove comments saying that it would be cool to
    add some locks to the code.

    Constify some pointers.

    Signed-off-by: Petr Vandrovec
    Signed-off-by: Arnd Bergmann

    Petr Vandrovec
     

01 Jul, 2006

1 commit

09 Jan, 2006

1 commit

  • 5160ee6fc   [PATCH] shrink dentry struct ... Browse Code »

    Some long time ago, dentry struct was carefully tuned so that on 32 bits
    UP, sizeof(struct dentry) was exactly 128, ie a power of 2, and a multiple
    of memory cache lines.

    Then RCU was added and dentry struct enlarged by two pointers, with nice
    results for SMP, but not so good on UP, because breaking the above tuning
    (128 + 8 = 136 bytes)

    This patch reverts this unwanted side effect, by using an union (d_u),
    where d_rcu and d_child are placed so that these two fields can share their
    memory needs.

    At the time d_free() is called (and d_rcu is really used), d_child is known
    to be empty and not touched by the dentry freeing.

    Lockless lookups only access d_name, d_parent, d_lock, d_op, d_flags (so
    the previous content of d_child is not needed if said dentry was unhashed
    but still accessed by a CPU because of RCU constraints)

    As dentry cache easily contains millions of entries, a size reduction is
    worth the extra complexity of the ugly C union.

    Signed-off-by: Eric Dumazet
    Cc: Dipankar Sarma
    Cc: Maneesh Soni
    Cc: Miklos Szeredi
    Cc: "Paul E. McKenney"
    Cc: Ian Kent
    Cc: Paul Jackson
    Cc: Al Viro
    Cc: Christoph Hellwig
    Cc: Trond Myklebust
    Cc: Neil Brown
    Cc: James Morris
    Cc: Stephen Smalley
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Eric Dumazet
     

26 Jun, 2005

1 commit

17 Apr, 2005

1 commit

  • 1da177e4c   Linux-2.6.12-rc2 ... Browse Code »

    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!

    Linus Torvalds