Re: [PATCH 22/22] mac_scsi: Fix pseudo DMA implementation

From: Hannes Reinecke
Date: Mon Mar 14 2016 - 04:00:03 EST


On 03/14/2016 05:27 AM, Finn Thain wrote:
> Fix various issues: Comments about bus errors are incorrect. The
> PDMA asm must return the size of the memory access that faulted so the
> transfer count can be adjusted accordingly. A phase change may cause a
> bus error but should not be treated as failure. A bus error does not
> always imply a phase change and generally the transfer may continue.
> Scatter/gather can't be used with PDMA due to overruns (which is a pity
> because peak throughput seems to double with SG_ALL).
>
> Signed-off-by: Finn Thain <fthain@xxxxxxxxxxxxxxxxxxx>
>
> ---
> drivers/scsi/NCR5380.h | 2
> drivers/scsi/mac_scsi.c | 210 ++++++++++++++++++++++++++----------------------
> 2 files changed, 118 insertions(+), 94 deletions(-)
>
Reviewed-by: Hannes Reinecke <hare@xxxxxxxx>

Cheers,

Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
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