1. 16 3月, 2009 3 次提交
    • J
      Move FASYNC bit handling to f_op->fasync() · 76398425
      Jonathan Corbet 提交于
      Removing the BKL from FASYNC handling ran into the challenge of keeping the
      setting of the FASYNC bit in filp->f_flags atomic with regard to calls to
      the underlying fasync() function.  Andi Kleen suggested moving the handling
      of that bit into fasync(); this patch does exactly that.  As a result, we
      have a couple of internal API changes: fasync() must now manage the FASYNC
      bit, and it will be called without the BKL held.
      
      As it happens, every fasync() implementation in the kernel with one
      exception calls fasync_helper().  So, if we make fasync_helper() set the
      FASYNC bit, we can avoid making any changes to the other fasync()
      functions - as long as those functions, themselves, have proper locking.
      Most fasync() implementations do nothing but call fasync_helper() - which
      has its own lock - so they are easily verified as correct.  The BKL had
      already been pushed down into the rest.
      
      The networking code has its own version of fasync_helper(), so that code
      has been augmented with explicit FASYNC bit handling.
      
      Cc: Al Viro <viro@ZenIV.linux.org.uk>
      Cc: David Miller <davem@davemloft.net>
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      Signed-off-by: NJonathan Corbet <corbet@lwn.net>
      76398425
    • J
      Use f_lock to protect f_flags · db1dd4d3
      Jonathan Corbet 提交于
      Traditionally, changes to struct file->f_flags have been done under BKL
      protection, or with no protection at all.  This patch causes all f_flags
      changes after file open/creation time to be done under protection of
      f_lock.  This allows the removal of some BKL usage and fixes a number of
      longstanding (if microscopic) races.
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      Cc: Al Viro <viro@ZenIV.linux.org.uk>
      Signed-off-by: NJonathan Corbet <corbet@lwn.net>
      db1dd4d3
    • J
      Rename struct file->f_ep_lock · 68499914
      Jonathan Corbet 提交于
      This lock moves out of the CONFIG_EPOLL ifdef and becomes f_lock.  For now,
      epoll remains the only user, but a future patch will use it to protect
      f_flags as well.
      
      Cc: Davide Libenzi <davidel@xmailserver.org>
      Reviewed-by: NChristoph Hellwig <hch@lst.de>
      Signed-off-by: NJonathan Corbet <corbet@lwn.net>
      68499914
  2. 13 3月, 2009 29 次提交
  3. 12 3月, 2009 8 次提交