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

Hannes Reinecke
2016-08-22T06:27:33Z

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@seagate.com>
> ---
> v6:
> - Change to use sg_copy_from_buffer as per Christoph Hellwig <hch@lst.de>
> 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@suse.com>

Cheers,

Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
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