On Mon, Dec 3, 2018 at 10:34 AM Dave Chinner <david@xxxxxxxxxxxxx> wrote: > > From: Dave Chinner <dchinner@xxxxxxxxxx> > > We want to enable cross-filesystem copy_file_range functionality > where possible, so push the "same superblock only" checks down to > the individual filesystem callouts so they can make their own > decisions about cross-superblock copy offload. > > Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx> Looks good. You may add Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx> Similar comment about overlayfs as patch 3. diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c > index 68736e5d6a56..34fb0398d016 100644 > --- a/fs/overlayfs/file.c > +++ b/fs/overlayfs/file.c > @@ -443,6 +443,14 @@ static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in, > const struct cred *old_cred; > loff_t ret; > > + /* > + * Temporary. Cross device copy checks should be left to the copy file > + * call on the real inodes, but existing behaviour checks the upper > + * files only. > + */ > + if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) > + return -EXDEV; > + > ret = ovl_real_fdget(file_out, &real_out); > if (ret) > return ret; > @@ -491,7 +499,7 @@ static ssize_t ovl_copy_file_range(struct file *file_in, loff_t pos_in, > ret = ovl_copyfile(file_in, pos_in, file_out, pos_out, len, flags, > OVL_COPY); > > - if (ret == -EOPNOTSUPP) > + if (ret == -EOPNOTSUPP || ret == -EXDEV) > ret = generic_copy_file_range(file_in, pos_in, file_out, > pos_out, len, flags); This fallback is already provided by vfs_copy_file_range(). Thanks, Amir.
