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Date:   Mon, 12 Jun 2023 09:41:38 -0400
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Subject: Re: [PATCH v2 8/8] cifs: update the ctime on a partial page write
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To:     Jeff Layton <jlayton@kernel.org>,
        Christian Brauner <brauner@kernel.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Brad Warrum <bwarrum@linux.ibm.com>,
        Ritu Agarwal <rituagar@linux.ibm.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Ian Kent <raven@themaw.net>,
        "Tigran A. Aivazian" <aivazian.tigran@gmail.com>,
        Jeremy Kerr <jk@ozlabs.org>, Ard Biesheuvel <ardb@kernel.org>,
        Namjae Jeon <linkinjeon@kernel.org>,
        Sungjong Seo <sj1557.seo@samsung.com>,
        Steve French <sfrench@samba.org>,
        Paulo Alcantara <pc@manguebit.com>,
        Ronnie Sahlberg <lsahlber@redhat.com>,
        Shyam Prasad N <sprasad@microsoft.com>,
        John Johansen <john.johansen@canonical.com>,
        Paul Moore <paul@paul-moore.com>,
        James Morris <jmorris@namei.org>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        Ruihan Li <lrh2000@pku.edu.cn>,
        Sebastian Reichel <sebastian.reichel@collabora.com>,
        Alan Stern <stern@rowland.harvard.edu>,
        Suren Baghdasaryan <surenb@google.com>,
        Wolfram Sang <wsa+renesas@sang-engineering.com>,
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        samba-technical@lists.samba.org, apparmor@lists.ubuntu.com,
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References: <20230612104524.17058-1-jlayton@kernel.org>
 <20230612104524.17058-9-jlayton@kernel.org>
From:   Tom Talpey <tom@talpey.com>
In-Reply-To: <20230612104524.17058-9-jlayton@kernel.org>
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On 6/12/2023 6:45 AM, Jeff Layton wrote:
> POSIX says:
> 
>      "Upon successful completion, where nbyte is greater than 0, write()
>       shall mark for update the last data modification and last file status
>       change timestamps of the file..."
> 
> Add the missing ctime update.
> 
> Signed-off-by: Jeff Layton <jlayton@kernel.org>
> ---
>   fs/smb/client/file.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/smb/client/file.c b/fs/smb/client/file.c
> index df88b8c04d03..a00038a326cf 100644
> --- a/fs/smb/client/file.c
> +++ b/fs/smb/client/file.c
> @@ -2596,7 +2596,7 @@ static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
>   					   write_data, to - from, &offset);
>   		cifsFileInfo_put(open_file);
>   		/* Does mm or vfs already set times? */
> -		inode->i_atime = inode->i_mtime = current_time(inode);
> +		inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);

Question. It appears that roughly half the filesystems in this series
don't touch the i_atime in this case. And the other half do. Which is
correct? Did they incorrectly set i_atime instead of i_ctime?

Tom.

>   		if ((bytes_written > 0) && (offset))
>   			rc = 0;
>   		else if (bytes_written < 0)