Merge tag 'for-linus-v3.8-rc6' of git://oss.sgi.com/xfs/xfs

Pull xfs bugfixes from Ben Myers:
 "Here are fixes for returning EFSCORRUPTED on probe of a non-xfs
  filesystem, the stack switch in xfs_bmapi_allocate, a crash in
  _xfs_buf_find, speculative preallocation as the filesystem nears
  ENOSPC, an unmount hang, a race with AIO, and a regression with
  xfs_fsr:

   - fix return value when filesystem probe finds no XFS magic, a
     regression introduced in 98021821.

   - fix stack switch in __xfs_bmapi_allocate by moving the check for
     stack switch up into xfs_bmapi_write.

   - fix oops in _xfs_buf_find by validating that the requested block is
     within the filesystem bounds.

   - limit speculative preallocation near ENOSPC.

   - fix an unmount hang in xfs_wait_buftarg by freeing the
     xfs_buf_log_item in xfs_buf_item_unlock.

   - fix a possible use after free with AIO.

   - fix xfs_swap_extents after removal of xfs_flushinval_pages, a
     regression introduced in commit fb595814."

* tag 'for-linus-v3.8-rc6' of git://oss.sgi.com/xfs/xfs:
  xfs: Fix xfs_swap_extents() after removal of xfs_flushinval_pages()
  xfs: Fix possible use-after-free with AIO
  xfs: fix shutdown hang on invalid inode during create
  xfs: limit speculative prealloc near ENOSPC thresholds
  xfs: fix _xfs_buf_find oops on blocks beyond the filesystem end
  xfs: pull up stack_switch check into xfs_bmapi_write
  xfs: Do not return EFSCORRUPTED when filesystem probe finds no XFS magic