Return-Path: Received: from mx142.netapp.com ([216.240.21.19]:62691 "EHLO mx142.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751798AbbKJVxq (ORCPT ); Tue, 10 Nov 2015 16:53:46 -0500 From: Anna Schumaker To: , , , , , , , , , , Subject: [PATCH v9 4/4] vfs: Add vfs_copy_file_range() support for pagecache copies Date: Tue, 10 Nov 2015 16:53:33 -0500 Message-ID: <1447192413-15376-5-git-send-email-Anna.Schumaker@Netapp.com> In-Reply-To: <1447192413-15376-1-git-send-email-Anna.Schumaker@Netapp.com> References: <1447192413-15376-1-git-send-email-Anna.Schumaker@Netapp.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-nfs-owner@vger.kernel.org List-ID: This allows us to have an in-kernel copy mechanism that avoids frequent switches between kernel and user space. This is especially useful so NFSD can support server-side copies. The default (flags=0) means to first attempt copy acceleration, but use the pagecache if that fails. Signed-off-by: Anna Schumaker Reviewed-by: Darrick J. Wong Reviewed-by: Padraig Brady Reviewed-by: Christoph Hellwig --- v9: - Don't remove call to rw_verify_area() --- fs/read_write.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/fs/read_write.c b/fs/read_write.c index 97c15ca..6f73af1 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1354,8 +1354,7 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, if (!(file_in->f_mode & FMODE_READ) || !(file_out->f_mode & FMODE_WRITE) || - (file_out->f_flags & O_APPEND) || - !file_out->f_op->copy_file_range) + (file_out->f_flags & O_APPEND)) return -EBADF; /* this could be relaxed once a method supports cross-fs copies */ @@ -1369,8 +1368,14 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, if (ret) return ret; - ret = file_out->f_op->copy_file_range(file_in, pos_in, file_out, pos_out, - len, flags); + ret = -EOPNOTSUPP; + 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 == -EOPNOTSUPP) + ret = do_splice_direct(file_in, &pos_in, file_out, &pos_out, + len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0); + if (ret > 0) { fsnotify_access(file_in); add_rchar(current, ret); -- 2.6.2