Return-Path: Received: from mx142.netapp.com ([216.240.21.19]:10583 "EHLO mx142.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760607AbbIDURZ (ORCPT ); Fri, 4 Sep 2015 16:17:25 -0400 From: Anna Schumaker To: , , , , , , , , , , Subject: [PATCH v1 8/8] vfs: Fall back on splice if no copy function defined Date: Fri, 4 Sep 2015 16:17:02 -0400 Message-ID: <1441397823-1203-9-git-send-email-Anna.Schumaker@Netapp.com> In-Reply-To: <1441397823-1203-1-git-send-email-Anna.Schumaker@Netapp.com> References: <1441397823-1203-1-git-send-email-Anna.Schumaker@Netapp.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-nfs-owner@vger.kernel.org List-ID: The NFS server will need a fallback for filesystems that don't have any kind of copy acceleration yet, and it should be generally useful to have an in-kernel copy to avoid lots of switches between kernel and user space. Users who only want a reflink can pass the COPY_REFLINK flag to disable the fallback. Signed-off-by: Anna Schumaker --- fs/read_write.c | 16 ++++++++++++---- include/linux/copy.h | 6 ++++++ include/uapi/linux/Kbuild | 1 + include/uapi/linux/copy.h | 6 ++++++ 4 files changed, 25 insertions(+), 4 deletions(-) create mode 100644 include/linux/copy.h create mode 100644 include/uapi/linux/copy.h diff --git a/fs/read_write.c b/fs/read_write.c index 9dafb7f..bd7e7e2 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -7,6 +7,7 @@ #include #include #include +#include #include #include #include @@ -1342,7 +1343,7 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in, struct inode *inode_out; ssize_t ret; - if (flags) + if (!((flags == 0) || (flags == COPY_REFLINK))) return -EINVAL; /* copy_file_range allows full ssize_t len, ignoring MAX_RW_COUNT */ @@ -1355,7 +1356,7 @@ 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 || !file_out->f_op->copy_file_range) + !file_in->f_op) return -EBADF; inode_in = file_inode(file_in); @@ -1377,8 +1378,15 @@ 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 < 0) && !(flags & COPY_REFLINK)) { + file_start_write(file_out); + ret = do_splice_direct(file_in, &pos_in, file_out, &pos_out, len, 0); + file_end_write(file_out); + } if (ret > 0) { fsnotify_access(file_in); add_rchar(current, ret); diff --git a/include/linux/copy.h b/include/linux/copy.h new file mode 100644 index 0000000..fd54543 --- /dev/null +++ b/include/linux/copy.h @@ -0,0 +1,6 @@ +#ifndef _LINUX_COPY_H +#define _LINUX_COPY_H + +#include + +#endif /* _LINUX_COPY_H */ diff --git a/include/uapi/linux/Kbuild b/include/uapi/linux/Kbuild index 1ff9942..b6109f3 100644 --- a/include/uapi/linux/Kbuild +++ b/include/uapi/linux/Kbuild @@ -90,6 +90,7 @@ header-y += coda_psdev.h header-y += coff.h header-y += connector.h header-y += const.h +header-y += copy.h header-y += cramfs_fs.h header-y += cuda.h header-y += cyclades.h diff --git a/include/uapi/linux/copy.h b/include/uapi/linux/copy.h new file mode 100644 index 0000000..68f3d65 --- /dev/null +++ b/include/uapi/linux/copy.h @@ -0,0 +1,6 @@ +#ifndef _UAPI_LINUX_COPY_H +#define _UAPI_LINUX_COPY_H + +#define COPY_REFLINK 1 /* only perform a reflink */ + +#endif /* _UAPI_LINUX_COPY_H */ -- 2.5.1