11 Jan, 2012

2 commits


04 Jan, 2012

2 commits


02 Nov, 2011

1 commit


21 Jul, 2011

2 commits


20 Jul, 2011

1 commit


28 May, 2011

1 commit


26 May, 2011

2 commits


13 Jan, 2011

2 commits


07 Jan, 2011

5 commits

  • Signed-off-by: Nick Piggin

    Nick Piggin
     
  • Require filesystems be aware of .d_revalidate being called in rcu-walk
    mode (nd->flags & LOOKUP_RCU). For now do a simple push down, returning
    -ECHILD from all implementations.

    Signed-off-by: Nick Piggin

    Nick Piggin
     
  • Reduce some branches and memory accesses in dcache lookup by adding dentry
    flags to indicate common d_ops are set, rather than having to check them.
    This saves a pointer memory access (dentry->d_op) in common path lookup
    situations, and saves another pointer load and branch in cases where we
    have d_op but not the particular operation.

    Patched with:

    git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i

    Signed-off-by: Nick Piggin

    Nick Piggin
     
  • Make d_count non-atomic and protect it with d_lock. This allows us to ensure a
    0 refcount dentry remains 0 without dcache_lock. It is also fairly natural when
    we start protecting many other dentry members with d_lock.

    Signed-off-by: Nick Piggin

    Nick Piggin
     
  • Change d_delete from a dentry deletion notification to a dentry caching
    advise, more like ->drop_inode. Require it to be constant and idempotent,
    and not take d_lock. This is how all existing filesystems use the callback
    anyway.

    This makes fine grained dentry locking of dput and dentry lru scanning
    much simpler.

    Signed-off-by: Nick Piggin

    Nick Piggin
     

26 Oct, 2010

1 commit


25 Oct, 2010

2 commits

  • Now that shared inode state is locked using the cii->c_lock, the BKL is
    only used to protect the upcall queues used to communicate with the
    userspace cache manager. The remaining state is all local and we can
    push the lock further down into coda_upcall().

    Signed-off-by: Yoshihisa Abe
    Signed-off-by: Jan Harkes
    Signed-off-by: Linus Torvalds

    Yoshihisa Abe
     
  • We mostly need it to protect cached user permissions. The c_flags field
    is advisory, reading the wrong value is harmless and in the worst case
    we hit a slow path where we have to make an extra upcall to the
    userspace cache manager when revalidating a dentry or inode.

    Signed-off-by: Yoshihisa Abe
    Signed-off-by: Jan Harkes
    Signed-off-by: Linus Torvalds

    Yoshihisa Abe
     

30 Mar, 2010

1 commit

  • …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
     

28 Mar, 2009

1 commit


23 Oct, 2008

1 commit

  • For execute permission on a regular files we need to check if file has
    any execute bits at all, regardless of capabilites.

    This check is normally performed by generic_permission() but was also
    added to the case when the filesystem defines its own ->permission()
    method. In the latter case the filesystem should be responsible for
    performing this check.

    Move the check from inode_permission() inside filesystems which are
    not calling generic_permission().

    Create a helper function execute_ok() that returns true if the inode
    is a directory or if any execute bits are present in i_mode.

    Also fix up the following code:

    - coda control file is never executable
    - sysctl files are never executable
    - hfs_permission seems broken on MAY_EXEC, remove
    - hfsplus_permission is eqivalent to generic_permission(), remove

    Signed-off-by: Miklos Szeredi

    Miklos Szeredi
     

27 Jul, 2008

1 commit

  • * kill nameidata * argument; map the 3 bits in ->flags anybody cares
    about to new MAY_... ones and pass with the mask.
    * kill redundant gfs2_iop_permission()
    * sanitize ecryptfs_permission()
    * fix remaining places where ->permission() instances might barf on new
    MAY_... found in mask.

    The obvious next target in that direction is permission(9)

    folded fix for nfs_permission() breakage from Miklos Szeredi

    Signed-off-by: Al Viro

    Al Viro
     

29 Apr, 2008

1 commit


22 Jul, 2007

1 commit

  • This is an variation on the patch sent by Christoph Hellwig which kills
    file_count abuse by the Coda kernel module by moving the coda_flush
    functionality into coda_release. However part of reason we were using the
    coda_flush callback was to allow Coda to pass errors that occur during
    writeback from the userspace cache manager back to close().

    As Al Viro explained on linux-fsdevel, it is impossible to guarantee that
    such errors can in fact be returned back to the caller. There are many
    cases where the last reference to a file is not released by the close
    system call and it is also impossible to pick some close as a 'last-close'
    and delay it until all other references have been destroyed.

    The CODA_STORE/CODA_RELEASE upcall combination is clearly a broken design,
    and it is better to remove it completely.

    Signed-off-by: Jan Harkes
    Cc: Christoph Hellwig
    Cc: Al Viro
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Jan Harkes
     

20 Jul, 2007

6 commits


16 Jul, 2007

1 commit


13 Feb, 2007

1 commit

  • Many struct inode_operations in the kernel can be "const". Marking them const
    moves these to the .rodata section, which avoids false sharing with potential
    dirty data. In addition it'll catch accidental writes at compile time to
    these shared resources.

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Arjan van de Ven
     

09 Dec, 2006

1 commit


01 Oct, 2006

2 commits

  • This is mostly included for parity with dec_nlink(), where we will have some
    more hooks. This one should stay pretty darn straightforward for now.

    Signed-off-by: Dave Hansen
    Acked-by: Christoph Hellwig
    Cc: Al Viro
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Dave Hansen
     
  • When a filesystem decrements i_nlink to zero, it means that a write must be
    performed in order to drop the inode from the filesystem.

    We're shortly going to have keep filesystems from being remounted r/o between
    the time that this i_nlink decrement and that write occurs.

    So, add a little helper function to do the decrements. We'll tie into it in a
    bit to note when i_nlink hits zero.

    Signed-off-by: Dave Hansen
    Acked-by: Christoph Hellwig
    Cc: Al Viro
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Dave Hansen
     

27 Sep, 2006

1 commit


29 Mar, 2006

1 commit

  • This is a conversion to make the various file_operations structs in fs/
    const. Basically a regexp job, with a few manual fixups

    The goal is both to increase correctness (harder to accidentally write to
    shared datastructures) and reducing the false sharing of cachelines with
    things that get dirty in .data (while .rodata is nicely read only and thus
    cache clean)

    Signed-off-by: Arjan van de Ven
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Arjan van de Ven