diff mbox

[v5,1/8] virtio: introduce virtio_is_little_endian() helper

Message ID 20150423152617.11795.13272.stgit@bahia.local (mailing list archive)
State New, archived
Headers show

Commit Message

Greg Kurz April 23, 2015, 3:26 p.m. UTC 
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
---
 include/linux/virtio_config.h |   17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)


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Comments

Thomas Huth April 23, 2015, 5:22 p.m. UTC | #1 
Am Thu, 23 Apr 2015 17:26:20 +0200
schrieb Greg Kurz <gkurz@linux.vnet.ibm.com>:

> Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
> ---
>  include/linux/virtio_config.h |   17 +++++++++++------
>  1 file changed, 11 insertions(+), 6 deletions(-)
> 
> diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
> index ca3ed78..bd1a582 100644
> --- a/include/linux/virtio_config.h
> +++ b/include/linux/virtio_config.h
> @@ -205,35 +205,40 @@ int virtqueue_set_affinity(struct virtqueue *vq, int cpu)
>  	return 0;
>  }
>  
> +static inline bool virtio_is_little_endian(struct virtio_device *vdev)
> +{
> +	return virtio_has_feature(vdev, VIRTIO_F_VERSION_1);
> +}

So this function returns false when _not_ using version 1, but running
on a little endian host + guest? Sounds confusing. Maybe you could name
it "virtio_is_v1()" or so instead?

 Thomas
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Thomas Huth April 23, 2015, 5:26 p.m. UTC | #2 
Am Thu, 23 Apr 2015 19:22:15 +0200
schrieb Thomas Huth <thuth@redhat.com>:

> Am Thu, 23 Apr 2015 17:26:20 +0200
> schrieb Greg Kurz <gkurz@linux.vnet.ibm.com>:
> 
> > Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
> > ---
> >  include/linux/virtio_config.h |   17 +++++++++++------
> >  1 file changed, 11 insertions(+), 6 deletions(-)
> > 
> > diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
> > index ca3ed78..bd1a582 100644
> > --- a/include/linux/virtio_config.h
> > +++ b/include/linux/virtio_config.h
> > @@ -205,35 +205,40 @@ int virtqueue_set_affinity(struct virtqueue *vq, int cpu)
> >  	return 0;
> >  }
> >  
> > +static inline bool virtio_is_little_endian(struct virtio_device *vdev)
> > +{
> > +	return virtio_has_feature(vdev, VIRTIO_F_VERSION_1);
> > +}
> 
> So this function returns false when _not_ using version 1, but running
> on a little endian host + guest? Sounds confusing. Maybe you could name
> it "virtio_is_v1()" or so instead?

Ah, never mind, I should have looked at patch 6 first, then it makes
sense. (maybe you could put a note to the later patch in this patch
description?)

 Thomas
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Thomas Huth April 23, 2015, 6:52 p.m. UTC | #3 
On Thu, 23 Apr 2015 17:26:20 +0200
Greg Kurz <gkurz@linux.vnet.ibm.com> wrote:

> Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
> ---
>  include/linux/virtio_config.h |   17 +++++++++++------
>  1 file changed, 11 insertions(+), 6 deletions(-)
> 
> diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
> index ca3ed78..bd1a582 100644
> --- a/include/linux/virtio_config.h
> +++ b/include/linux/virtio_config.h
> @@ -205,35 +205,40 @@ int virtqueue_set_affinity(struct virtqueue *vq, int cpu)
>  	return 0;
>  }
>  
> +static inline bool virtio_is_little_endian(struct virtio_device *vdev)
> +{
> +	return virtio_has_feature(vdev, VIRTIO_F_VERSION_1);
> +}
> +
>  /* Memory accessors */
>  static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val)
>  {
> -	return __virtio16_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
> +	return __virtio16_to_cpu(virtio_is_little_endian(vdev), val);
>  }
>  
>  static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val)
>  {
> -	return __cpu_to_virtio16(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
> +	return __cpu_to_virtio16(virtio_is_little_endian(vdev), val);
>  }
>  
>  static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val)
>  {
> -	return __virtio32_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
> +	return __virtio32_to_cpu(virtio_is_little_endian(vdev), val);
>  }
>  
>  static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val)
>  {
> -	return __cpu_to_virtio32(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
> +	return __cpu_to_virtio32(virtio_is_little_endian(vdev), val);
>  }
>  
>  static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val)
>  {
> -	return __virtio64_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
> +	return __virtio64_to_cpu(virtio_is_little_endian(vdev), val);
>  }
>  
>  static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
>  {
> -	return __cpu_to_virtio64(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
> +	return __cpu_to_virtio64(virtio_is_little_endian(vdev), val);
>  }

Reviewed-by: Thomas Huth <thuth@redhat.com>
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diff mbox

Patch

diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index ca3ed78..bd1a582 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -205,35 +205,40 @@  int virtqueue_set_affinity(struct virtqueue *vq, int cpu)
 	return 0;
 }
 
+static inline bool virtio_is_little_endian(struct virtio_device *vdev)
+{
+	return virtio_has_feature(vdev, VIRTIO_F_VERSION_1);
+}
+
 /* Memory accessors */
 static inline u16 virtio16_to_cpu(struct virtio_device *vdev, __virtio16 val)
 {
-	return __virtio16_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
+	return __virtio16_to_cpu(virtio_is_little_endian(vdev), val);
 }
 
 static inline __virtio16 cpu_to_virtio16(struct virtio_device *vdev, u16 val)
 {
-	return __cpu_to_virtio16(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
+	return __cpu_to_virtio16(virtio_is_little_endian(vdev), val);
 }
 
 static inline u32 virtio32_to_cpu(struct virtio_device *vdev, __virtio32 val)
 {
-	return __virtio32_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
+	return __virtio32_to_cpu(virtio_is_little_endian(vdev), val);
 }
 
 static inline __virtio32 cpu_to_virtio32(struct virtio_device *vdev, u32 val)
 {
-	return __cpu_to_virtio32(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
+	return __cpu_to_virtio32(virtio_is_little_endian(vdev), val);
 }
 
 static inline u64 virtio64_to_cpu(struct virtio_device *vdev, __virtio64 val)
 {
-	return __virtio64_to_cpu(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
+	return __virtio64_to_cpu(virtio_is_little_endian(vdev), val);
 }
 
 static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val)
 {
-	return __cpu_to_virtio64(virtio_has_feature(vdev, VIRTIO_F_VERSION_1), val);
+	return __cpu_to_virtio64(virtio_is_little_endian(vdev), val);
 }
 
 /* Config space accessors. */