From: David Laight
> Transfer requests for usb disks can contain a large number of 4k fragments.
> Assume that it doesn't matter if there are LINK TRB in fragment lists
> that are 1k aligned.
>
> This should stop errors when transfer requests for usb disks contain
> more fragments that will fit in a ring segment.
>
> Signed-off-by: David Laight <[email protected]>
> ---
> Note that this patch just allows large numbers of aligned fragments for
> bulk scatter-gather transfers.
> It doesn't remove the need for the patch that changes the way the ownership
> of the the first TRB is set in order to avoid the controller seeing 'dangling'
> LINK TRBs.
> However it does reduce the likelyhood of dangling LINK TRBs, so might seem to
> make the other patch unnecessary.
>
> I've only compile tested it - but it should be fine.
Tested with aligned transfers for a usb memory stick and unaligned
ones for ethernet.
I failed to generate more than 30 sg entries.
Interestingly the disk transfers (eg from dd bs=1M) are pairs of
122880 (15 * 8192) and 8192 bytes. Seems suboptimal!
David
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