[PATCH] fs: remove ->sendpage

[Christoph Hellwig]

->sendpage is only called from generic_splice_sendpage.  The only user of
generic_splice_sendpage is socket_file_ops, which is also the only
instance that actually implements ->sendpage.  Remove the ->sendpage file
operation and just open code the logic in the socket code.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
 fs/splice.c        | 45 ---------------------------------------------
 include/linux/fs.h |  3 ---
 net/socket.c       | 33 ++++++++++++++++++++-------------
 3 files changed, 20 insertions(+), 61 deletions(-)

diff --git a/fs/splice.c b/fs/splice.c
index d7c8a7c4db07ff..f644e293098dac 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -425,30 +425,6 @@ static ssize_t default_file_splice_read(struct file *in, loff_t *ppos,
 	return res;
 }
 
-/*
- * Send 'sd->len' bytes to socket from 'sd->file' at position 'sd->pos'
- * using sendpage(). Return the number of bytes sent.
- */
-static int pipe_to_sendpage(struct pipe_inode_info *pipe,
-			    struct pipe_buffer *buf, struct splice_desc *sd)
-{
-	struct file *file = sd->u.file;
-	loff_t pos = sd->pos;
-	int more;
-
-	if (!likely(file->f_op->sendpage))
-		return -EINVAL;
-
-	more = (sd->flags & SPLICE_F_MORE) ? MSG_MORE : 0;
-
-	if (sd->len < sd->total_len &&
-	    pipe_occupancy(pipe->head, pipe->tail) > 1)
-		more |= MSG_SENDPAGE_NOTLAST;
-
-	return file->f_op->sendpage(file, buf->page, buf->offset,
-				    sd->len, &pos, more);
-}
-
 static void wakeup_pipe_writers(struct pipe_inode_info *pipe)
 {
 	smp_mb();
@@ -815,27 +791,6 @@ static ssize_t default_file_splice_write(struct pipe_inode_info *pipe,
 	return ret;
 }
 
-/**
- * generic_splice_sendpage - splice data from a pipe to a socket
- * @pipe:	pipe to splice from
- * @out:	socket to write to
- * @ppos:	position in @out
- * @len:	number of bytes to splice
- * @flags:	splice modifier flags
- *
- * Description:
- *    Will send @len bytes from the pipe to a network socket. No data copying
- *    is involved.
- *
- */
-ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe, struct file *out,
-				loff_t *ppos, size_t len, unsigned int flags)
-{
-	return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_sendpage);
-}
-
-EXPORT_SYMBOL(generic_splice_sendpage);
-
 /*
  * Attempt to initiate a splice from pipe to file.
  */
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 7519ae003a082c..1133b71417d28a 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1819,7 +1819,6 @@ struct file_operations {
 	int (*fsync) (struct file *, loff_t, loff_t, int datasync);
 	int (*fasync) (int, struct file *, int);
 	int (*lock) (struct file *, int, struct file_lock *);
-	ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
 	unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
 	int (*check_flags)(int);
 	int (*flock) (struct file *, int, struct file_lock *);
@@ -3045,8 +3044,6 @@ 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,
-		struct file *out, loff_t *, size_t len, unsigned int flags);
 extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
 		loff_t *opos, size_t len, unsigned int flags);
 
diff --git a/net/socket.c b/net/socket.c
index 0c0144604f818a..dd93bbd61c22d3 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -123,8 +123,8 @@ static long compat_sock_ioctl(struct file *file,
 			      unsigned int cmd, unsigned long arg);
 #endif
 static int sock_fasync(int fd, struct file *filp, int on);
-static ssize_t sock_sendpage(struct file *file, struct page *page,
-			     int offset, size_t size, loff_t *ppos, int more);
+static ssize_t sock_splice_write(struct pipe_inode_info *pipe,
+		struct file *out, loff_t *ppos, size_t len, unsigned int flags);
 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
 				struct pipe_inode_info *pipe, size_t len,
 				unsigned int flags);
@@ -159,8 +159,7 @@ static const struct file_operations socket_file_ops = {
 	.mmap =		sock_mmap,
 	.release =	sock_close,
 	.fasync =	sock_fasync,
-	.sendpage =	sock_sendpage,
-	.splice_write = generic_splice_sendpage,
+	.splice_write = sock_splice_write,
 	.splice_read =	sock_splice_read,
 	.show_fdinfo =	sock_show_fdinfo,
 };
@@ -929,19 +928,27 @@ int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
 }
 EXPORT_SYMBOL(kernel_recvmsg);
 
-static ssize_t sock_sendpage(struct file *file, struct page *page,
-			     int offset, size_t size, loff_t *ppos, int more)
+static int pipe_to_sendpage(struct pipe_inode_info *pipe,
+			    struct pipe_buffer *buf, struct splice_desc *sd)
 {
-	struct socket *sock;
-	int flags;
+	struct socket *sock = sd->u.file->private_data;
+	int flags = 0;
 
-	sock = file->private_data;
+	if (sd->u.file->f_flags & O_NONBLOCK)
+		flags |= MSG_DONTWAIT;
+	if (sd->flags & SPLICE_F_MORE)
+		flags |= MSG_MORE;
+	if (sd->len < sd->total_len &&
+	    pipe_occupancy(pipe->head, pipe->tail) > 1)
+		flags |= MSG_SENDPAGE_NOTLAST;
 
-	flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
-	/* more is a combination of MSG_MORE and MSG_SENDPAGE_NOTLAST */
-	flags |= more;
+	return kernel_sendpage(sock, buf->page, buf->offset, sd->len, flags);
+}
 
-	return kernel_sendpage(sock, page, offset, size, flags);
+static ssize_t sock_splice_write(struct pipe_inode_info *pipe,
+		struct file *out, loff_t *ppos, size_t len, unsigned int flags)
+{
+	return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_sendpage);
 }
 
 static ssize_t sock_splice_read(struct file *file, loff_t *ppos,
-- 
2.28.0