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Message-ID: <e06621b2-8b33-41ec-a049-1befe83cdb5c@oracle.com>
Date: Wed, 6 Mar 2024 11:14:16 +0000
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Subject: Re: [RFC 4/8] ext4: Add statx and other atomic write helper routines
To: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com>,
        linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org
Cc: Ojaswin Mujoo <ojaswin@linux.ibm.com>, Jan Kara <jack@suse.cz>,
        Theodore Ts'o <tytso@mit.edu>, Matthew Wilcox <willy@infradead.org>,
        "Darrick J . Wong" <djwong@kernel.org>,
        Luis Chamberlain
 <mcgrof@kernel.org>, linux-kernel@vger.kernel.org
References: <555cc3e262efa77ee5648196362f415a1efc018d.1709361537.git.ritesh.list@gmail.com>
 <9def15d6ffb88f7352713c65292513fab532112a.1709361537.git.ritesh.list@gmail.com>
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From: John Garry <john.g.garry@oracle.com>
Organization: Oracle Corporation
In-Reply-To: <9def15d6ffb88f7352713c65292513fab532112a.1709361537.git.ritesh.list@gmail.com>
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On 02/03/2024 07:42, Ritesh Harjani (IBM) wrote:
>   	}
>   
> +	if (request_mask & STATX_WRITE_ATOMIC) {
> +		unsigned int fsawu_min = 0, fsawu_max = 0;
> +
> +		/*
> +		 * Get fsawu_[min|max] value which we can advertise to userspace
> +		 * in statx call, if we support atomic writes using
> +		 * EXT4_MF_ATOMIC_WRITE_FSAWU.
> +		 */
> +		if (ext4_can_atomic_write_fsawu(inode->i_sb)) {

To me, it does not make sense to fill this in unless 
EXT4_INODE_ATOMIC_WRITE is also set for the inode.

> +			ext4_atomic_write_fsawu(inode->i_sb, &fsawu_min,
> +						&fsawu_max);
> +		}
> +
> +		generic_fill_statx_atomic_writes(stat, fsawu_min, fsawu_max);
> +	}
> +
>   	flags = ei->i_flags & EXT4_FL_USER_VISIBLE;