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Subject: Re: [PATCH v6 02/16] chardev: introduce cdev_get_by_path()
To:     Matthew Wilcox <willy@infradead.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Jens Axboe <axboe@fb.com>,
        Chaitanya Kulkarni <Chaitanya.Kulkarni@wdc.com>,
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        Stephen Bates <sbates@raithlin.com>,
        linux-block@vger.kernel.org, Keith Busch <kbusch@kernel.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        linux-fsdevel@vger.kernel.org, Max Gurtovoy <maxg@mellanox.com>,
        Logan Gunthorpe <logang@deltatee.com>,
        Christoph Hellwig <hch@lst.de>
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From:   Sagi Grimberg <sagi@grimberg.me>
Message-ID: <27943e06-a503-162e-356b-abb9e106ab2e@grimberg.me>
Date:   Thu, 25 Jul 2019 12:05:29 -0700
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>>> NVMe-OF is configured using configfs. The target is specified by the
>>> user writing a path to a configfs attribute. This is the way it works
>>> today but with blkdev_get_by_path()[1]. For the passthru code, we need
>>> to get a nvme_ctrl instead of a block_device, but the principal is the same.
>>
>> Why isn't a fd being passed in there instead of a random string?
> 
> I suppose we could echo a string of the file descriptor number there,
> and look up the fd in the process' file descriptor table ...

Assuming that there is a open handle somewhere out there...

> I'll get my coat.

Grab mine too..