tree 16d7ab46582219e349df6bfd48c6e20a5ba8e8fc
parent ad36d1a533da91d3448029b4da1113c5b880f25d
author Jeff Garzik <jgarzik@pobox.com> 1131995186 -0500
committer Jeff Garzik <jgarzik@pobox.com> 1131995186 -0500

[libata] fix bugs in ATAPI padding DMA mapping code

The ATAPI pad-to-next-32bit-boundary code modifies the scatterlist's
length variable, sometimes to zero.  x86-64 platform would oops if a
zero-length scatterlist entry was asked to be mapped.  Work around this
by ensuring that we never DMA-map a zero length buffer or SG entry.