Revert "splice, net: Add a splice_eof op to file-ops and socket-ops"

This reverts commit 4713b7c756 which is
commit 2bfc668509 upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: I32d590ae0e683aed39bfddcd736301bce6e0dec9
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

fs/splice.c

@@ -763,17 +763,6 @@ static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
 	return out->f_op->splice_write(pipe, out, ppos, len, flags);
 }
 
-/*
- * Indicate to the caller that there was a premature EOF when reading from the
- * source and the caller didn't indicate they would be sending more data after
- * this.
- */
-static void do_splice_eof(struct splice_desc *sd)
-{
-	if (sd->splice_eof)
-		sd->splice_eof(sd);
-}
-
 /*
  * Attempt to initiate a splice from a file to a pipe.
  */
@@ -874,7 +863,7 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
 
 		ret = do_splice_to(in, &pos, pipe, len, flags);
 		if (unlikely(ret <= 0))
-			goto read_failure;
+			goto out_release;
 
 		read_len = ret;
 		sd->total_len = read_len;
@@ -914,15 +903,6 @@ done:
 	file_accessed(in);
 	return bytes;
 
-read_failure:
-	/*
-	 * If the user did *not* set SPLICE_F_MORE *and* we didn't hit that
-	 * "use all of len" case that cleared SPLICE_F_MORE, *and* we did a
-	 * "->splice_in()" that returned EOF (ie zero) *and* we have sent at
-	 * least 1 byte *then* we will also do the ->splice_eof() call.
-	 */
-	if (ret == 0 && !more && len > 0 && bytes)
-		do_splice_eof(sd);
 out_release:
 	/*
 	 * If we did an incomplete transfer we must release
@@ -951,14 +931,6 @@ static int direct_splice_actor(struct pipe_inode_info *pipe,
 			      sd->flags);
 }
 
-static void direct_file_splice_eof(struct splice_desc *sd)
-{
-	struct file *file = sd->u.file;
-
-	if (file->f_op->splice_eof)
-		file->f_op->splice_eof(file);
-}
-
 /**
  * do_splice_direct - splices data directly between two files
  * @in:		file to splice from
@@ -984,7 +956,6 @@ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
 		.flags		= flags,
 		.pos		= *ppos,
 		.u.file		= out,
-		.splice_eof	= direct_file_splice_eof,
 		.opos		= opos,
 	};
 	long ret;

include/linux/fs.h

@@ -2187,7 +2187,6 @@ struct file_operations {
 	int (*flock) (struct file *, int, struct file_lock *);
 	ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsigned int);
 	ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
-	void (*splice_eof)(struct file *file);
 	int (*setlease)(struct file *, long, struct file_lock **, void **);
 	long (*fallocate)(struct file *file, int mode, loff_t offset,
 			  loff_t len);

include/linux/net.h

@@ -210,7 +210,6 @@ struct proto_ops {
 				      int offset, size_t size, int flags);
 	ssize_t 	(*splice_read)(struct socket *sock,  loff_t *ppos,
 				       struct pipe_inode_info *pipe, size_t len, unsigned int flags);
-	void		(*splice_eof)(struct socket *sock);
 	int		(*set_peek_off)(struct sock *sk, int val);
 	int		(*peek_len)(struct socket *sock);
 

include/linux/splice.h

@@ -38,7 +38,6 @@ struct splice_desc {
 		struct file *file;	/* file to read/write */
 		void *data;		/* cookie */
 	} u;
-	void (*splice_eof)(struct splice_desc *sd); /* Unexpected EOF handler */
 	loff_t pos;			/* file position */
 	loff_t *opos;			/* sendfile: output position */
 	size_t num_spliced;		/* number of bytes already spliced */

include/net/sock.h

@@ -1293,7 +1293,6 @@ struct proto {
 					   size_t len, int flags, int *addr_len);
 	int			(*sendpage)(struct sock *sk, struct page *page,
 					int offset, size_t size, int flags);
-	void			(*splice_eof)(struct socket *sock);
 	int			(*bind)(struct sock *sk,
 					struct sockaddr *addr, int addr_len);
 	int			(*bind_add)(struct sock *sk,

net/socket.c

@@ -130,7 +130,6 @@ static ssize_t sock_sendpage(struct file *file, struct page *page,
 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
 				struct pipe_inode_info *pipe, size_t len,
 				unsigned int flags);
-static void sock_splice_eof(struct file *file);
 
 #ifdef CONFIG_PROC_FS
 static void sock_show_fdinfo(struct seq_file *m, struct file *f)
@@ -165,7 +164,6 @@ static const struct file_operations socket_file_ops = {
 	.sendpage =	sock_sendpage,
 	.splice_write = generic_splice_sendpage,
 	.splice_read =	sock_splice_read,
-	.splice_eof =	sock_splice_eof,
 	.show_fdinfo =	sock_show_fdinfo,
 };
 
@@ -1093,14 +1091,6 @@ static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
 	return sock->ops->splice_read(sock, ppos, pipe, len, flags);
 }
 
-static void sock_splice_eof(struct file *file)
-{
-	struct socket *sock = file->private_data;
-
-	if (sock->ops->splice_eof)
-		sock->ops->splice_eof(sock);
-}
-
 static ssize_t sock_read_iter(struct kiocb *iocb, struct iov_iter *to)
 {
 	struct file *file = iocb->ki_filp;