Linux Virtualization - Nov 2014 - [PATCH 52/56] drivers/char/virtio: support compiling out splice

Compile out splice support from virtio character driver when the splice-family
of syscalls is not supported by the system (i.e. CONFIG_SYSCALL_SPLICE is
undefined).

Signed-off-by: Pieter Smith <pieter at boesman.nl>
---
 drivers/char/virtio_console.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index b585b47..de5e2cb 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -870,6 +870,7 @@ struct sg_list {
 	struct scatterlist *sg;
 };
 
+#ifdef CONFIG_SYSCALL_SPLICE
 static int pipe_to_sg(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
 			struct splice_desc *sd)
 {
@@ -976,6 +977,7 @@ error_out:
 	pipe_unlock(pipe);
 	return ret;
 }
+#endif /* #ifdef CONFIG_SYSCALL_SPLICE */
 
 static unsigned int port_fops_poll(struct file *filp, poll_table *wait)
 {
@@ -1109,7 +1111,7 @@ static const struct file_operations port_fops = {
 	.open  = port_fops_open,
 	.read  = port_fops_read,
 	.write = port_fops_write,
-	.splice_write = port_fops_splice_write,
+	SPLICE_WRITE_INIT(port_fops_splice_write)
 	.poll  = port_fops_poll,
 	.release = port_fops_release,
 	.fasync = port_fops_fasync,
-- 
1.9.1

On Thu, Nov 13, 2014 at 10:23:29PM +0100, Pieter Smith
wrote:
> Compile out splice support from virtio character driver when the
splice-family
> of syscalls is not supported by the system (i.e. CONFIG_SYSCALL_SPLICE is
> undefined).
> 
> Signed-off-by: Pieter Smith <pieter at boesman.nl>
> ---
>  drivers/char/virtio_console.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
> index b585b47..de5e2cb 100644
> --- a/drivers/char/virtio_console.c
> +++ b/drivers/char/virtio_console.c
> @@ -870,6 +870,7 @@ struct sg_list {
>  	struct scatterlist *sg;
>  };
>  
> +#ifdef CONFIG_SYSCALL_SPLICE
>  static int pipe_to_sg(struct pipe_inode_info *pipe, struct pipe_buffer
*buf,
>  			struct splice_desc *sd)
>  {
> @@ -976,6 +977,7 @@ error_out:
>  	pipe_unlock(pipe);
>  	return ret;
>  }
> +#endif /* #ifdef CONFIG_SYSCALL_SPLICE */
Not worth the #ifdef mess.