On Sat, Oct 27, 2018 at 5:09 AM Dave Chinner <david@xxxxxxxxxxxxx> wrote:
>
> On Fri, Oct 26, 2018 at 04:10:46PM -0400, Olga Kornievskaia wrote:
> > From: Olga Kornievskaia <kolga@xxxxxxxxxx>
> >
> > This patch makes it the responsibility of individual filesystems to
> > allow or deny cross device copies. Both NFS and CIFS have operations
> > for cross-server copies, and later patches will implement this feature.
> >
> > Note that as of this patch, the copy_file_range() function might be passed
> > superblocks from different filesystem types. -EXDEV should be returned
> > if cross device copies aren't supported, causing the VFS to fall back
> > on using do_splice_direct().
> >
> > Signed-off-by: Olga Kornievskaia <kolga@xxxxxxxxxx>
> > ---
> > Documentation/filesystems/porting | 7 +++++++
> > fs/cifs/cifsfs.c | 3 +++
> > fs/nfs/nfs4file.c | 3 +++
> > fs/overlayfs/file.c | 3 +++
> > fs/read_write.c | 9 +++------
> > 5 files changed, 19 insertions(+), 6 deletions(-)
> >
> > diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting
> > index 7b7b845..897e1e7 100644
> > --- a/Documentation/filesystems/porting
> > +++ b/Documentation/filesystems/porting
> > @@ -622,3 +622,10 @@ in your dentry operations instead.
> > alloc_file_clone(file, flags, ops) does not affect any caller's references.
> > On success you get a new struct file sharing the mount/dentry with the
> > original, on failure - ERR_PTR().
> > +--
> > +[mandatory]
> > + ->copy_file_range() may now be passed files which belong to two
> > + different superblocks of the same file system type or which belong
> > + to two different filesystems types all together. As before, the
> > + destination's copy_file_range() is the function which is called.
> > + If it cannot copy ranges from the source, it should return -EXDEV.
> > diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
> > index 7065426..f2d7f4f 100644
> > --- a/fs/cifs/cifsfs.c
> > +++ b/fs/cifs/cifsfs.c
> > @@ -1114,6 +1114,9 @@ static ssize_t cifs_copy_file_range(struct file *src_file, loff_t off,
> > unsigned int xid = get_xid();
> > ssize_t rc;
> >
> > + if (src_file->f_inode->i_sb != dst_file->f_inode->i_sb)
>
> file_inode(file)->i_sb, please.
>
> > + return -EXDEV;
> > +
> > rc = cifs_file_copychunk_range(xid, src_file, off, dst_file, destoff,
> > len, flags);
> > free_xid(xid);
> > diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
> > index 4288a6e..09df688 100644
> > --- a/fs/nfs/nfs4file.c
> > +++ b/fs/nfs/nfs4file.c
> > @@ -135,6 +135,9 @@ static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in,
> > {
> > ssize_t ret;
> >
> > + if (file_in->f_inode->i_sb != file_out->f_inode->i_sb)
> > + return -EXDEV;
> > +
> > if (file_inode(file_in) == file_inode(file_out))
> > return -EINVAL;
>
> Please look at the code around your modifications and make sure your
> additions are consistent with it.
Will make the changes. Thanks.
>
> > @@ -1588,7 +1584,8 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in,
> > * Try cloning first, this is supported by more file systems, and
> > * more efficient if both clone and copy are supported (e.g. NFS).
> > */
> > - if (file_in->f_op->clone_file_range) {
> > + if (inode_in->i_sb == inode_out->i_sb &&
> > + file_in->f_op->clone_file_range) {
>
> if (inode_in->i_sb == inode_out->i_sb &&
> file_in->f_op->clone_file_range) {
>
> Cheers,
>
> Dave.
> --
> Dave Chinner
> david@xxxxxxxxxxxxx
