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author | Greg Kurz <gkurz@linux.vnet.ibm.com> | 2015-04-24 14:26:24 +0200 |
---|---|---|
committer | Michael S. Tsirkin <mst@redhat.com> | 2015-06-01 15:48:54 +0200 |
commit | 7d82410950aa74adccf035c332e409af2bb93e92 (patch) | |
tree | ff910c555820a2bf0fbd7b17231fa75d0cea5427 | |
parent | ab27c07f607253f928cbc8c64d9c0d273df09e6b (diff) | |
download | op-kernel-dev-7d82410950aa74adccf035c332e409af2bb93e92.zip op-kernel-dev-7d82410950aa74adccf035c332e409af2bb93e92.tar.gz |
virtio: add explicit big-endian support to memory accessors
The current memory accessors logic is:
- little endian if little_endian
- native endian (i.e. no byteswap) if !little_endian
If we want to fully support cross-endian vhost, we also need to be
able to convert to big endian.
Instead of changing the little_endian argument to some 3-value enum, this
patch changes the logic to:
- little endian if little_endian
- big endian if !little_endian
The native endian case is handled by all users with a trivial helper. This
patch doesn't change any functionality, nor it does add overhead.
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
-rw-r--r-- | drivers/net/macvtap.c | 3 | ||||
-rw-r--r-- | drivers/net/tun.c | 3 | ||||
-rw-r--r-- | drivers/vhost/vhost.h | 3 | ||||
-rw-r--r-- | include/linux/virtio_byteorder.h | 24 | ||||
-rw-r--r-- | include/linux/virtio_config.h | 3 | ||||
-rw-r--r-- | include/linux/vringh.h | 3 |
6 files changed, 24 insertions, 15 deletions
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 4fdb881..072ccba 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -51,7 +51,8 @@ struct macvtap_queue { static inline bool macvtap_is_little_endian(struct macvtap_queue *q) { - return q->flags & MACVTAP_VNET_LE; + return q->flags & MACVTAP_VNET_LE || + virtio_legacy_is_little_endian(); } static inline u16 macvtap16_to_cpu(struct macvtap_queue *q, __virtio16 val) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 301e87c..b210139 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -208,7 +208,8 @@ struct tun_struct { static inline bool tun_is_little_endian(struct tun_struct *tun) { - return tun->flags & TUN_VNET_LE; + return tun->flags & TUN_VNET_LE || + virtio_legacy_is_little_endian(); } static inline u16 tun16_to_cpu(struct tun_struct *tun, __virtio16 val) diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 6a49960..a4fa33a 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -175,7 +175,8 @@ static inline bool vhost_has_feature(struct vhost_virtqueue *vq, int bit) static inline bool vhost_is_little_endian(struct vhost_virtqueue *vq) { - return vhost_has_feature(vq, VIRTIO_F_VERSION_1); + return vhost_has_feature(vq, VIRTIO_F_VERSION_1) || + virtio_legacy_is_little_endian(); } /* Memory accessors */ diff --git a/include/linux/virtio_byteorder.h b/include/linux/virtio_byteorder.h index 51865d0..ce63a2c 100644 --- a/include/linux/virtio_byteorder.h +++ b/include/linux/virtio_byteorder.h @@ -3,17 +3,21 @@ #include <linux/types.h> #include <uapi/linux/virtio_types.h> -/* - * Low-level memory accessors for handling virtio in modern little endian and in - * compatibility native endian format. - */ +static inline bool virtio_legacy_is_little_endian(void) +{ +#ifdef __LITTLE_ENDIAN + return true; +#else + return false; +#endif +} static inline u16 __virtio16_to_cpu(bool little_endian, __virtio16 val) { if (little_endian) return le16_to_cpu((__force __le16)val); else - return (__force u16)val; + return be16_to_cpu((__force __be16)val); } static inline __virtio16 __cpu_to_virtio16(bool little_endian, u16 val) @@ -21,7 +25,7 @@ static inline __virtio16 __cpu_to_virtio16(bool little_endian, u16 val) if (little_endian) return (__force __virtio16)cpu_to_le16(val); else - return (__force __virtio16)val; + return (__force __virtio16)cpu_to_be16(val); } static inline u32 __virtio32_to_cpu(bool little_endian, __virtio32 val) @@ -29,7 +33,7 @@ static inline u32 __virtio32_to_cpu(bool little_endian, __virtio32 val) if (little_endian) return le32_to_cpu((__force __le32)val); else - return (__force u32)val; + return be32_to_cpu((__force __be32)val); } static inline __virtio32 __cpu_to_virtio32(bool little_endian, u32 val) @@ -37,7 +41,7 @@ static inline __virtio32 __cpu_to_virtio32(bool little_endian, u32 val) if (little_endian) return (__force __virtio32)cpu_to_le32(val); else - return (__force __virtio32)val; + return (__force __virtio32)cpu_to_be32(val); } static inline u64 __virtio64_to_cpu(bool little_endian, __virtio64 val) @@ -45,7 +49,7 @@ static inline u64 __virtio64_to_cpu(bool little_endian, __virtio64 val) if (little_endian) return le64_to_cpu((__force __le64)val); else - return (__force u64)val; + return be64_to_cpu((__force __be64)val); } static inline __virtio64 __cpu_to_virtio64(bool little_endian, u64 val) @@ -53,7 +57,7 @@ static inline __virtio64 __cpu_to_virtio64(bool little_endian, u64 val) if (little_endian) return (__force __virtio64)cpu_to_le64(val); else - return (__force __virtio64)val; + return (__force __virtio64)cpu_to_be64(val); } #endif /* _LINUX_VIRTIO_BYTEORDER */ diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 170947e..e5ce8ab 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -207,7 +207,8 @@ int virtqueue_set_affinity(struct virtqueue *vq, int cpu) static inline bool virtio_is_little_endian(struct virtio_device *vdev) { - return virtio_has_feature(vdev, VIRTIO_F_VERSION_1); + return virtio_has_feature(vdev, VIRTIO_F_VERSION_1) || + virtio_legacy_is_little_endian(); } /* Memory accessors */ diff --git a/include/linux/vringh.h b/include/linux/vringh.h index 3ed62ef..bc6c28d 100644 --- a/include/linux/vringh.h +++ b/include/linux/vringh.h @@ -228,7 +228,8 @@ static inline void vringh_notify(struct vringh *vrh) static inline bool vringh_is_little_endian(const struct vringh *vrh) { - return vrh->little_endian; + return vrh->little_endian || + virtio_legacy_is_little_endian(); } static inline u16 vringh16_to_cpu(const struct vringh *vrh, __virtio16 val) |