1. 23 3月, 2011 1 次提交
    • J
      zlib: slim down zlib_deflate() workspace when possible · 565d76cb
      Jim Keniston 提交于
      Instead of always creating a huge (268K) deflate_workspace with the
      maximum compression parameters (windowBits=15, memLevel=8), allow the
      caller to obtain a smaller workspace by specifying smaller parameter
      values.
      
      For example, when capturing oops and panic reports to a medium with
      limited capacity, such as NVRAM, compression may be the only way to
      capture the whole report.  In this case, a small workspace (24K works
      fine) is a win, whether you allocate the workspace when you need it (i.e.,
      during an oops or panic) or at boot time.
      
      I've verified that this patch works with all accepted values of windowBits
      (positive and negative), memLevel, and compression level.
      Signed-off-by: NJim Keniston <jkenisto@us.ibm.com>
      Cc: Herbert Xu <herbert@gondor.apana.org.au>
      Cc: David Miller <davem@davemloft.net>
      Cc: Chris Mason <chris.mason@oracle.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      565d76cb
  2. 02 2月, 2011 1 次提交
    • E
      fs/vfs/security: pass last path component to LSM on inode creation · 2a7dba39
      Eric Paris 提交于
      SELinux would like to implement a new labeling behavior of newly created
      inodes.  We currently label new inodes based on the parent and the creating
      process.  This new behavior would also take into account the name of the
      new object when deciding the new label.  This is not the (supposed) full path,
      just the last component of the path.
      
      This is very useful because creating /etc/shadow is different than creating
      /etc/passwd but the kernel hooks are unable to differentiate these
      operations.  We currently require that userspace realize it is doing some
      difficult operation like that and than userspace jumps through SELinux hoops
      to get things set up correctly.  This patch does not implement new
      behavior, that is obviously contained in a seperate SELinux patch, but it
      does pass the needed name down to the correct LSM hook.  If no such name
      exists it is fine to pass NULL.
      Signed-off-by: NEric Paris <eparis@redhat.com>
      2a7dba39
  3. 07 1月, 2011 2 次提交
    • N
      fs: provide rcu-walk aware permission i_ops · b74c79e9
      Nick Piggin 提交于
      Signed-off-by: NNick Piggin <npiggin@kernel.dk>
      b74c79e9
    • N
      fs: icache RCU free inodes · fa0d7e3d
      Nick Piggin 提交于
      RCU free the struct inode. This will allow:
      
      - Subsequent store-free path walking patch. The inode must be consulted for
        permissions when walking, so an RCU inode reference is a must.
      - sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
        to take i_lock no longer need to take sb_inode_list_lock to walk the list in
        the first place. This will simplify and optimize locking.
      - Could remove some nested trylock loops in dcache code
      - Could potentially simplify things a bit in VM land. Do not need to take the
        page lock to follow page->mapping.
      
      The downsides of this is the performance cost of using RCU. In a simple
      creat/unlink microbenchmark, performance drops by about 10% due to inability to
      reuse cache-hot slab objects. As iterations increase and RCU freeing starts
      kicking over, this increases to about 20%.
      
      In cases where inode lifetimes are longer (ie. many inodes may be allocated
      during the average life span of a single inode), a lot of this cache reuse is
      not applicable, so the regression caused by this patch is smaller.
      
      The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
      however this adds some complexity to list walking and store-free path walking,
      so I prefer to implement this at a later date, if it is shown to be a win in
      real situations. I haven't found a regression in any non-micro benchmark so I
      doubt it will be a problem.
      Signed-off-by: NNick Piggin <npiggin@kernel.dk>
      fa0d7e3d
  4. 04 12月, 2010 3 次提交
  5. 29 10月, 2010 1 次提交
  6. 26 10月, 2010 1 次提交
  7. 25 10月, 2010 6 次提交
  8. 05 10月, 2010 2 次提交
    • A
      BKL: Remove BKL from jffs2 · 1a028dd2
      Arnd Bergmann 提交于
      The BKL is only used in put_super, fill_super and remount_fs that are all
      three protected by the superblocks s_umount rw_semaphore. Therefore it is
      safe to remove the BKL entirely.
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Cc: David Woodhouse <dwmw2@infradead.org>
      1a028dd2
    • J
      BKL: Explicitly add BKL around get_sb/fill_super · db719222
      Jan Blunck 提交于
      This patch is a preparation necessary to remove the BKL from do_new_mount().
      It explicitly adds calls to lock_kernel()/unlock_kernel() around
      get_sb/fill_super operations for filesystems that still uses the BKL.
      
      I've read through all the code formerly covered by the BKL inside
      do_kern_mount() and have satisfied myself that it doesn't need the BKL
      any more.
      
      do_kern_mount() is already called without the BKL when mounting the rootfs
      and in nfsctl. do_kern_mount() calls vfs_kern_mount(), which is called
      from various places without BKL: simple_pin_fs(), nfs_do_clone_mount()
      through nfs_follow_mountpoint(), afs_mntpt_do_automount() through
      afs_mntpt_follow_link(). Both later functions are actually the filesystems
      follow_link inode operation. vfs_kern_mount() is calling the specified
      get_sb function and lets the filesystem do its job by calling the given
      fill_super function.
      
      Therefore I think it is safe to push down the BKL from the VFS to the
      low-level filesystems get_sb/fill_super operation.
      
      [arnd: do not add the BKL to those file systems that already
             don't use it elsewhere]
      Signed-off-by: NJan Blunck <jblunck@infradead.org>
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Cc: Matthew Wilcox <matthew@wil.cx>
      Cc: Christoph Hellwig <hch@infradead.org>
      db719222
  9. 10 8月, 2010 3 次提交
  10. 09 8月, 2010 1 次提交
  11. 08 8月, 2010 1 次提交
  12. 22 7月, 2010 1 次提交
  13. 06 6月, 2010 1 次提交
  14. 03 6月, 2010 2 次提交
  15. 28 5月, 2010 2 次提交
  16. 22 5月, 2010 1 次提交
  17. 20 5月, 2010 4 次提交
  18. 19 5月, 2010 3 次提交
  19. 30 3月, 2010 1 次提交
    • T
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo 提交于
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit 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: NTejun Heo <tj@kernel.org>
      Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  20. 18 3月, 2010 1 次提交
  21. 25 2月, 2010 1 次提交
  22. 17 12月, 2009 1 次提交
    • C
      sanitize xattr handler prototypes · 431547b3
      Christoph Hellwig 提交于
      Add a flags argument to struct xattr_handler and pass it to all xattr
      handler methods.  This allows using the same methods for multiple
      handlers, e.g. for the ACL methods which perform exactly the same action
      for the access and default ACLs, just using a different underlying
      attribute.  With a little more groundwork it'll also allow sharing the
      methods for the regular user/trusted/secure handlers in extN, ocfs2 and
      jffs2 like it's already done for xfs in this patch.
      
      Also change the inode argument to the handlers to a dentry to allow
      using the handlers mechnism for filesystems that require it later,
      e.g. cifs.
      
      [with GFS2 bits updated by Steven Whitehouse <swhiteho@redhat.com>]
      Signed-off-by: NChristoph Hellwig <hch@lst.de>
      Reviewed-by: NJames Morris <jmorris@namei.org>
      Acked-by: NJoel Becker <joel.becker@oracle.com>
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      431547b3