[PATCH v21 29/30] splice: Remove generic_file_splice_read()

David Howells
2023-05-20T00:02:32Z

Remove generic_file_splice_read() as it has been replaced with calls to
filemap_splice_read() and copy_splice_read().

With this, ITER_PIPE is no longer used.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Christoph Hellwig <hch@lst.de>
cc: Jens Axboe <axboe@kernel.dk>
cc: Steve French <smfrench@gmail.com>
cc: Al Viro <viro@zeniv.linux.org.uk>
cc: David Hildenbrand <david@redhat.com>
cc: John Hubbard <jhubbard@nvidia.com>
cc: linux-mm@kvack.org
cc: linux-block@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
---

Notes:
ver #21)
- Move zero-len check to vfs_splice_read().
- Move s_maxbytes check to filemap_splice_read().
- DIO (and DAX) are handled by vfs_splice_read().

ver #20)
- Use s_maxbytes from the backing store (in->f_mapping), not the front
inode (especially for a blockdev).

ver #18)
- Split out the change to cifs to make it use generic_file_splice_read().
- Split out the unexport of filemap_splice_read() (still needed by cifs).

fs/splice.c | 43 -------------------------------------------
include/linux/fs.h | 2 --
2 files changed, 45 deletions(-)

diff --git a/fs/splice.c b/fs/splice.c
index 8268248df3a9..9be4cb3b9879 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -386,49 +386,6 @@ ssize_t copy_splice_read(struct file *in, loff_t *ppos,
}
EXPORT_SYMBOL(copy_splice_read);

-/**
- * generic_file_splice_read - splice data from file to a pipe
- * @in: file to splice from
- * @ppos: position in @in
- * @pipe: pipe to splice to
- * @len: number of bytes to splice
- * @flags: splice modifier flags
- *
- * Description:
- * Will read pages from given file and fill them into a pipe. Can be
- * used as long as it has more or less sane ->read_iter().
- *
- */
-ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
- struct pipe_inode_info *pipe, size_t len,
- unsigned int flags)
-{
- struct iov_iter to;
- struct kiocb kiocb;
- int ret;
-
- iov_iter_pipe(&to, ITER_DEST, pipe, len);
- init_sync_kiocb(&kiocb, in);
- kiocb.ki_pos = *ppos;
- ret = call_read_iter(in, &kiocb, &to);
- if (ret > 0) {
- *ppos = kiocb.ki_pos;
- file_accessed(in);
- } else if (ret < 0) {
- /* free what was emitted */
- pipe_discard_from(pipe, to.start_head);
- /*
- * callers of ->splice_read() expect -EAGAIN on
- * "can't put anything in there", rather than -EFAULT.
- */
- if (ret == -EFAULT)
- ret = -EAGAIN;
- }
-
- return ret;
-}
-EXPORT_SYMBOL(generic_file_splice_read);
-
const struct pipe_buf_operations default_pipe_buf_ops = {
.release = generic_pipe_buf_release,
.try_steal = generic_pipe_buf_try_steal,
diff --git a/include/linux/fs.h b/include/linux/fs.h
index e3c22efa413e..08ba2ae1d3ce 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2755,8 +2755,6 @@ ssize_t filemap_splice_read(struct file *in, loff_t *ppos,
ssize_t copy_splice_read(struct file *in, loff_t *ppos,
struct pipe_inode_info *pipe,
size_t len, unsigned int flags);
-extern ssize_t generic_file_splice_read(struct file *, loff_t *,
- struct pipe_inode_info *, size_t, unsigned int);
extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
struct file *, loff_t *, size_t, unsigned int);
extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,