* TRIM / UNMAP read response
@ 2011-08-12 13:28 joystick
2011-08-12 14:55 ` Douglas Gilbert
0 siblings, 1 reply; 2+ messages in thread
From: joystick @ 2011-08-12 13:28 UTC (permalink / raw)
To: linux-ide, linux-scsi@vger.kernel.org
Hi all IDE and SCSI ml's,
is it guaranteed by the standards that reading from a device a region
that has been TRIMmed (IDE) or UNMAPped (SCSI) will certainly return zeroes?
Thank you
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: TRIM / UNMAP read response
2011-08-12 13:28 TRIM / UNMAP read response joystick
@ 2011-08-12 14:55 ` Douglas Gilbert
0 siblings, 0 replies; 2+ messages in thread
From: Douglas Gilbert @ 2011-08-12 14:55 UTC (permalink / raw)
To: joystick; +Cc: linux-ide, linux-scsi@vger.kernel.org
On 11-08-12 09:28 AM, joystick wrote:
> Hi all IDE and SCSI ml's,
>
> is it guaranteed by the standards that reading from a device a region that has
> been TRIMmed (IDE) or UNMAPped (SCSI) will certainly return zeroes?
ATA:
In 'hdparm -I' you need to see this line:
* Deterministic read ZEROs after TRIM
[See the ATA IDENTIFY DEVICE command]
SCSI:
In the READ CAPACITY (16) response the LBPRZ needs to
be set to 1. Recently the same LBPRZ bit was added to
the Logical Block Provisioning VPD page (sbc3r27.pdf).
Doug Gilbert
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2011-08-12 14:55 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2011-08-12 13:28 TRIM / UNMAP read response joystick
2011-08-12 14:55 ` Douglas Gilbert
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).