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Message-ID: <be98bee0-4ddc-194f-82be-767e0bb9f60f@molgen.mpg.de>
Date:   Sat, 8 Apr 2023 17:16:42 +0200
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Subject: Re: [PATCH v3 02/11] block: Block Device Filtering Mechanism
To:     Sergei Shtepa <sergei.shtepa@veeam.com>, axboe@kernel.dk,
        hch@infradead.org, corbet@lwn.net, snitzer@kernel.org
Cc:     viro@zeniv.linux.org.uk, brauner@kernel.org, willy@infradead.org,
        kch@nvidia.com, martin.petersen@oracle.com, vkoul@kernel.org,
        ming.lei@redhat.com, gregkh@linuxfoundation.org,
        linux-block@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
References: <20230404140835.25166-1-sergei.shtepa@veeam.com>
 <20230404140835.25166-3-sergei.shtepa@veeam.com>
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From:   Donald Buczek <buczek@molgen.mpg.de>
In-Reply-To: <20230404140835.25166-3-sergei.shtepa@veeam.com>
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Hi, Sergei,

On 4/4/23 16:08, Sergei Shtepa wrote:
> The block device filtering mechanism is an API that allows to attach
> block device filters. Block device filters allow perform additional
> processing for I/O units.
> [...]
> diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h
> index b7b56871029c..1848d62979a4 100644
> --- a/include/uapi/linux/fs.h
> +++ b/include/uapi/linux/fs.h
> @@ -185,6 +185,11 @@ struct fsxattr {
>   #define BLKROTATIONAL _IO(0x12,126)
>   #define BLKZEROOUT _IO(0x12,127)
>   #define BLKGETDISKSEQ _IOR(0x12,128,__u64)
> +/* 13* is defined in linux/blkzoned.h */

nit: This is already explained in the comment below your insert.

Best

  Donald

> +#define BLKFILTER_ATTACH	_IOWR(0x12, 140, struct blkfilter_name)
> +#define BLKFILTER_DETACH	_IOWR(0x12, 141, struct blkfilter_name)
> +#define BLKFILTER_CTL		_IOWR(0x12, 142, struct blkfilter_ctl)
> +
>   /*
>    * A jump here: 130-136 are reserved for zoned block devices
>    * (see uapi/linux/blkzoned.h)