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Message-ID: <938111ca-d3c7-9888-24f8-0017a989002b@kernel.dk>
Date:   Fri, 20 May 2022 08:34:25 -0600
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Subject: Re: [PATCH] splice: allow direct splicing with chardevs
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To:     "Jason A. Donenfeld" <Jason@zx2c4.com>,
        linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk
Cc:     Jens Axboe <axboe@suse.de>
References: <20220520095747.123748-1-Jason@zx2c4.com>
From:   Jens Axboe <axboe@kernel.dk>
In-Reply-To: <20220520095747.123748-1-Jason@zx2c4.com>
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Precedence: bulk

On 5/20/22 3:57 AM, Jason A. Donenfeld wrote:
> The original direct splicing mechanism from Jens required the input to
> be a regular file because it was avoiding the special socket case. It
> also recognized blkdevs as being close enough to a regular file. But it
> forgot about chardevs, which behave the same way and work fine here.
> 
> This commit adds the missing S_ISCHR condition so that chardevs such as
> /dev/urandom can be directly spliced without strangely returning
> -EINVAL.

Should be fine to turn this on for char devices:

Reviewed-by: Jens Axboe <axboe@kernel.dk>

-- 
Jens Axboe