From: "hch@lst.de" <hch@lst.de>
To: Keith Busch <kbusch@kernel.org>
Cc: "hch@lst.de" <hch@lst.de>,
Javier Gonzalez <javier.gonz@samsung.com>,
"javier@javigon.com" <javier@javigon.com>,
"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
"linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
"sagi@grimberg.me" <sagi@grimberg.me>,
"axboe@kernel.dk" <axboe@kernel.dk>,
"joshi.k@samsung.com" <joshi.k@samsung.com>,
"Klaus B. Jensen" <k.jensen@samsung.com>,
"Niklas.Cassel@wdc.com" <Niklas.Cassel@wdc.com>
Subject: Re: [PATCH V2] nvme: report capacity 0 for non supported ZNS SSDs
Date: Mon, 2 Nov 2020 19:58:51 +0100 [thread overview]
Message-ID: <20201102185851.GA21349@lst.de> (raw)
In-Reply-To: <20201102183355.GB1970293@dhcp-10-100-145-180.wdc.com>
On Mon, Nov 02, 2020 at 10:33:55AM -0800, Keith Busch wrote:
> I can see this going one of two ways:
>
> a) Set up the existing controller character device with a generic
> disk-less request_queue to the IO queues accepting IO commands to
> arbitrary NSIDs.
>
> b) Each namespace that can't be supported gets their own character
> device.
>
> I'm leaning toward option "a". While it doesn't create handles to unique
> namespaces, it has more resilience to potentially future changes. And I
> recall the target side had a potential use for that, too.
The problem with a) is that it can't be used to give users or groups
access to just one namespaces, so it causes a real access control
nightmare. The problem with b) is that now applications will break
when we add support for new command sets or features. I think
c) Each namespace gets its own character device, period.
is the only sensible option.
next prev parent reply other threads:[~2020-11-02 18:58 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20201102161505eucas1p19415e34eb0b14c7eca5a2c648569cf1e@eucas1p1.samsung.com>
[not found] ` <0916865d50c640e3aa95dc542f3986b9@CAMSVWEXC01.scsc.local>
2020-11-02 16:30 ` [PATCH V2] nvme: report capacity 0 for non supported ZNS SSDs Niklas Cassel
2020-11-02 21:25 ` Javier Gonzalez
2020-11-02 18:08 ` [PATCH V2] " hch
2020-11-02 18:33 ` Keith Busch
2020-11-02 18:58 ` hch [this message]
2020-11-02 21:24 ` Javier Gonzalez
2020-11-03 9:06 ` hch
2020-11-03 14:10 ` Javier Gonzalez
2020-11-03 15:26 ` hch
2020-11-03 15:54 ` Javier Gonzalez
2020-11-04 14:26 ` [PATCH V2] " Hannes Reinecke
2020-11-04 14:29 ` hch
2020-11-04 14:46 ` Hannes Reinecke
2020-11-05 7:37 ` hch
2020-11-05 7:42 ` Hannes Reinecke
2020-11-02 13:22 Javier González
2020-11-02 15:44 ` Keith Busch
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