From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753091AbeEGUoN (ORCPT ); Mon, 7 May 2018 16:44:13 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:38018 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752389AbeEGUoL (ORCPT ); Mon, 7 May 2018 16:44:11 -0400 Date: Mon, 7 May 2018 13:43:50 -0700 From: "Darrick J. Wong" To: Miklos Szeredi Cc: linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 21/35] ovl: add reflink/copyfile/dedup support Message-ID: <20180507204350.GB9510@magnolia> References: <20180507083807.28792-1-mszeredi@redhat.com> <20180507083807.28792-22-mszeredi@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180507083807.28792-22-mszeredi@redhat.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8886 signatures=668698 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1711220000 definitions=main-1805070203 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 07, 2018 at 10:37:53AM +0200, Miklos Szeredi wrote: > Since set of arguments are so similar, handle in a common helper. > > Signed-off-by: Miklos Szeredi > --- > fs/overlayfs/file.c | 88 +++++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 88 insertions(+) > > diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c > index ce871a15e185..2ac95c95e8e6 100644 > --- a/fs/overlayfs/file.c > +++ b/fs/overlayfs/file.c > @@ -382,6 +382,90 @@ static long ovl_compat_ioctl(struct file *file, unsigned int cmd, > return ovl_ioctl(file, cmd, arg); > } > > +enum ovl_copyop { > + OVL_COPY, > + OVL_CLONE, > + OVL_DEDUPE, > +}; > + > +static s64 ovl_copyfile(struct file *file_in, loff_t pos_in, > + struct file *file_out, loff_t pos_out, > + u64 len, unsigned int flags, enum ovl_copyop op) > +{ > + struct inode *inode_out = file_inode(file_out); > + struct fd real_in, real_out; > + const struct cred *old_cred; > + s64 ret; > + > + ret = ovl_real_fdget(file_out, &real_out); > + if (ret) > + return ret; > + > + ret = ovl_real_fdget(file_in, &real_in); > + if (ret) { > + fdput(real_out); > + return ret; > + } > + > + old_cred = ovl_override_creds(file_inode(file_out)->i_sb); > + switch (op) { > + case OVL_COPY: > + ret = vfs_copy_file_range(real_in.file, pos_in, > + real_out.file, pos_out, len, flags); > + break; > + > + case OVL_CLONE: > + ret = vfs_clone_file_range(real_in.file, pos_in, > + real_out.file, pos_out, len); > + break; > + > + case OVL_DEDUPE: > + ret = vfs_dedupe_file_range_one(real_in.file, pos_in, > + real_out.file, pos_out, len); > + break; > + } > + revert_creds(old_cred); > + > + /* Update size */ > + ovl_copyattr(ovl_inode_real(inode_out), inode_out); > + > + fdput(real_in); > + fdput(real_out); > + > + return ret; > +} > + > +static ssize_t ovl_copy_file_range(struct file *file_in, loff_t pos_in, > + struct file *file_out, loff_t pos_out, > + size_t len, unsigned int flags) > +{ > + return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, flags, > + OVL_COPY); > +} > + > +static int ovl_clone_file_range(struct file *file_in, loff_t pos_in, > + struct file *file_out, loff_t pos_out, u64 len) > +{ > + return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, 0, > + OVL_CLONE); > +} > + > +static s64 ovl_dedupe_file_range(struct file *file_in, loff_t pos_in, > + struct file *file_out, loff_t pos_out, > + u64 len) > +{ > + /* > + * Don't copy up because of a dedupe request, this wouldn't make sense > + * most of the time (data would be duplicated instead of deduplicated). > + */ > + if (!ovl_inode_upper(file_inode(file_in)) || > + !ovl_inode_upper(file_inode(file_out))) > + return -EPERM; /me wonders, why not EOPNOTSUPP? That's what we've been using (in xfs anyway) for "filesystem doesn't want to let you do this". (Or I guess EXDEV, but "cross-device link not supported" might not be quite what you want users to see...) --D > + > + return ovl_copyfile(file_in, pos_in, file_out, pos_out, len, 0, > + OVL_DEDUPE); > +} > + > const struct file_operations ovl_file_operations = { > .open = ovl_open, > .release = ovl_release, > @@ -393,4 +477,8 @@ const struct file_operations ovl_file_operations = { > .fallocate = ovl_fallocate, > .unlocked_ioctl = ovl_ioctl, > .compat_ioctl = ovl_compat_ioctl, > + > + .copy_file_range = ovl_copy_file_range, > + .clone_file_range = ovl_clone_file_range, > + .dedupe_file_range = ovl_dedupe_file_range, > }; > -- > 2.14.3 >