From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Rybchenko <arybchenko@solarflare.com>
Subject: Re: [PATCH v7 1/2] mbuf: support attaching external
	buffer to mbuf
Date: Fri, 27 Apr 2018 10:22:31 +0300
Message-ID: <5a7f368a-8b1b-705a-2186-be76c59720cf@solarflare.com>
References: <20180310012532.15809-1-yskoh@mellanox.com>
 <20180427000123.31888-1-yskoh@mellanox.com>
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Cc: <dev@dpdk.org>, <konstantin.ananyev@intel.com>,
 <stephen@networkplumber.org>, <thomas@monjalon.net>,
 <adrien.mazarguil@6wind.com>, <nelio.laranjeiro@6wind.com>
To: Yongseok Koh <yskoh@mellanox.com>, <wenzhuo.lu@intel.com>,
 <jingjing.wu@intel.com>, <olivier.matz@6wind.com>
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On 04/27/2018 03:01 AM, Yongseok Koh wrote:
> This patch introduces a new way of attaching an external buffer to a mbuf.
>
> Attaching an external buffer is quite similar to mbuf indirection in
> replacing buffer addresses and length of a mbuf, but a few differences:
>    - When an indirect mbuf is attached, refcnt of the direct mbuf would be
>      2 as long as the direct mbuf itself isn't freed after the attachment.
>      In such cases, the buffer area of a direct mbuf must be read-only. But
>      external buffer has its own refcnt and it starts from 1. Unless
>      multiple mbufs are attached to a mbuf having an external buffer, the
>      external buffer is writable.
>    - There's no need to allocate buffer from a mempool. Any buffer can be
>      attached with appropriate free callback.
>    - Smaller metadata is required to maintain shared data such as refcnt.
>
> Signed-off-by: Yongseok Koh <yskoh@mellanox.com>
> Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
> Acked-by: Olivier Matz <olivier.matz@6wind.com>

Many thanks,
Acked-by: Andrew Rybchenko <arybchenko@solarflare.com>