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To:     Dave Chinner <david@fromorbit.com>
Cc:     Sarthak Kukreti <sarthakkukreti@chromium.org>,
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Subject: Re: [PATCH v7 0/5] Introduce provisioning primitives
From:   "Martin K. Petersen" <martin.petersen@oracle.com>
Organization: Oracle Corporation
Message-ID: <yq1sfb21zsa.fsf@ca-mkp.ca.oracle.com>
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Date:   Wed, 07 Jun 2023 22:03:40 -0400
In-Reply-To: <ZHqOvq3ORETQB31m@dread.disaster.area> (Dave Chinner's message of
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Dave,

> Possibly unintentionally, I didn't call it REQ_OP_PROVISION but that's
> what I intended - the operation does not contain data at all. It's an
> operation like REQ_OP_DISCARD or REQ_OP_WRITE_ZEROS - it contains a
> range of sectors that need to be provisioned (or discarded), and
> nothing else.

Yep. That's also how SCSI defines it. The act of provisioning a block
range is done through an UNMAP command using a special flag. All it does
is pin down those LBAs so future writes to them won't result in ENOSPC.

-- 
Martin K. Petersen	Oracle Linux Engineering