From: Andy Adamson <andros@xxxxxxxxxx> Calling file_in->copy_file_range file operations function will not work for NFS inter-server to server COPY. In the intra-ssc case, when the destination server calls vfs_copy_file_range (from nfsd_copy_range) to perform the copy offload, it uses an NFS client file_in struct file setup to let the destination server (acting as an NFS client) NFS READ the data to be copied from the source server. Using the NFS file_in thus results in calling the NFS client copy_file_range f-ops, nfs4_copy_file_range, which results in the destination server trying to start a new COPY (calling COPY_NOTIFY etc) causing a circular call mess. Instead, vfs_copy_file_range should use the file_out f_ops->copy_file_range proceedure if it has one. The vfs_copy_file_range is a destination based operation as the source is simply being read, while the destination is being written and can therefore utilize a copy_file_range call if provided. Signed-off-by: Andy Adamson <andros@xxxxxxxxxx> --- fs/read_write.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/read_write.c b/fs/read_write.c index da28205..2a4b7bd 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1395,8 +1395,8 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, return ret; ret = -ENOTSUPP; - if (file_in->f_op->copy_file_range) - ret = file_in->f_op->copy_file_range(file_in, pos_in, file_out, + if (file_out->f_op->copy_file_range) + ret = file_out->f_op->copy_file_range(file_in, pos_in, file_out, pos_out, len, flags); if (ret == -ENOTSUPP) ret = do_splice_direct(file_in, &pos_in, file_out, &pos_out, len, flags); -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
