MFC r207251:

MFC r207251:
  It seems ale(4) controllers do not like to see TCP payload in the
  first descriptor in TSO case. Otherwise controller can generate bad
  frames during TSO. To address it, make sure to pull up ethernet +
  IP + TCP header with options in first buffer. Also ensure the
  buffer length of the first descriptor for TSO covers entire ethernet
  + IP + TCP with options and setup additional Tx descriptor if the
  first buffer includes TCP payload.

  Tested by:	Amar Takhar <verm <> darkbeer dot org >

git-svn-id: svn://svn.freebsd.org/base/stable/8@207546 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f