From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
Preparatory patch to carve out do_copy_file_range() from
vfs_copy_file_range
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
---
fs/read_write.c | 60 ++++++++++++++++++++++++++++++++-------------------------
1 file changed, 34 insertions(+), 26 deletions(-)
diff --git a/fs/read_write.c b/fs/read_write.c
index c4eabbfc90df..525f2a67e15a 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1541,6 +1541,38 @@ COMPAT_SYSCALL_DEFINE4(sendfile64, int, out_fd, int, in_fd,
}
#endif
+static ssize_t do_copy_file_range(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out,
+ size_t len, unsigned int flags)
+{
+ ssize_t ret = 0;
+
+ if (len == 0)
+ return 0;
+
+ /*
+ * 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) {
+ ret = file_in->f_op->clone_file_range(file_in, pos_in,
+ file_out, pos_out, len);
+ if (ret == 0)
+ return len;
+ }
+
+ 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)
+ return ret;
+ }
+
+ ret = do_splice_direct(file_in, &pos_in, file_out, &pos_out,
+ len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0);
+ return ret;
+}
+
/*
* copy_file_range() differs from regular file read and write in that it
* specifically allows return partial success. When it does so is up to
@@ -1579,35 +1611,11 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in,
if (inode_in->i_sb != inode_out->i_sb)
return -EXDEV;
- if (len == 0)
- return 0;
-
file_start_write(file_out);
- /*
- * 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) {
- ret = file_in->f_op->clone_file_range(file_in, pos_in,
- file_out, pos_out, len);
- if (ret == 0) {
- ret = len;
- goto done;
- }
- }
-
- 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)
- goto done;
- }
-
- ret = do_splice_direct(file_in, &pos_in, file_out, &pos_out,
- len > MAX_RW_COUNT ? MAX_RW_COUNT : len, 0);
+ ret = do_copy_file_range(file_in, pos_in,
+ file_out, pos_out, len, flags);
-done:
if (ret > 0) {
fsnotify_access(file_in);
add_rchar(current, ret);
--
2.16.3
