Re: [PATCH v6 2/4] Add support for SCT Write Same

[Hannes Reinecke]

On 08/22/2016 06:23 AM, Shaun Tancheff wrote:
> SATA drives may support write same via SCT. This is useful
> for setting the drive contents to a specific pattern (0's).
> 
> Translate a SCSI WRITE SAME 16 command to be either a DSM TRIM
> command or an SCT Write Same command.
> 
> Based on the UNMAP flag:
>   - When set translate to DSM TRIM
>   - When not set translate to SCT Write Same
> 
> Signed-off-by: Shaun Tancheff <shaun.tancheff@xxxxxxxxxxx>
> ---
> v6:
>  - Change to use sg_copy_from_buffer as per Christoph Hellwig <hch@xxxxxx>
> v5:
>  - Addressed review comments
>  - Report support for ZBC only for zoned devices.
>  - kmap page during rewrite
>  - Fix unmap set to require trim or error, if not unmap then sct write
>    same or error.
> v4:
>  - Added partial MAINTENANCE_IN opcode simulation
>  - Dropped all changes in drivers/scsi/*
>  - Changed to honor the UNMAP flag -> TRIM, no UNMAP -> SCT.
> v3:
>  - Demux UNMAP/TRIM from WRITE SAME
> v2:
>  - Remove fugly ata hacking from sd.c
> 
>  drivers/ata/libata-scsi.c | 199 +++++++++++++++++++++++++++++++++++++++-------
>  include/linux/ata.h       |  43 ++++++++++
>  2 files changed, 213 insertions(+), 29 deletions(-)
> 
Reviewed-by: Hannes Reinecke <hare@xxxxxxxx>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		   Teamlead Storage & Networking
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