vfs: add vfs_iocb_iter_[read|write] helper functions

This doesn't cause any behavior changes and will be used by overlay async
IO implementation.

Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 98e0349adb52..28315a286bab 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2078,6 +2078,18 @@ static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp)
 	};
 }
 
+static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src,
+			       struct file *filp)
+{
+	*kiocb = (struct kiocb) {
+		.ki_filp = filp,
+		.ki_flags = kiocb_src->ki_flags,
+		.ki_hint = kiocb_src->ki_hint,
+		.ki_ioprio = kiocb_src->ki_ioprio,
+		.ki_pos = kiocb_src->ki_pos,
+	};
+}
+
 /*
  * Inode state bits.  Protected by inode->i_lock
  *
@@ -3108,6 +3120,10 @@ ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos,
 		rwf_t flags);
 ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos,
 		rwf_t flags);
+ssize_t vfs_iocb_iter_read(struct file *file, struct kiocb *iocb,
+			   struct iov_iter *iter);
+ssize_t vfs_iocb_iter_write(struct file *file, struct kiocb *iocb,
+			    struct iov_iter *iter);
 
 /* fs/block_dev.c */
 extern ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to);