From caa0e2d0e331a04cbc1cb9bca3169c1d94b80838 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Wed, 1 Apr 2015 08:21:51 +1030 Subject: virtio_config: reorder functions This simply reorders functions in virtio_config so width access wrapper helpers are all together. Drops an extra empty line while we are at it. Signed-off-by: Michael S. Tsirkin Signed-off-by: Rusty Russell --- include/linux/virtio_config.h | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) (limited to 'include/linux/virtio_config.h') diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index ca3ed78e5ec7..22d33034b578 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -298,13 +298,6 @@ static inline __virtio64 cpu_to_virtio64(struct virtio_device *vdev, u64 val) } \ } while(0) -static inline u8 virtio_cread8(struct virtio_device *vdev, unsigned int offset) -{ - u8 ret; - vdev->config->get(vdev, offset, &ret, sizeof(ret)); - return ret; -} - /* Read @count fields, @bytes each. */ static inline void __virtio_cread_many(struct virtio_device *vdev, unsigned int offset, @@ -326,7 +319,6 @@ static inline void __virtio_cread_many(struct virtio_device *vdev, } while (gen != old); } - static inline void virtio_cread_bytes(struct virtio_device *vdev, unsigned int offset, void *buf, size_t len) @@ -334,6 +326,13 @@ static inline void virtio_cread_bytes(struct virtio_device *vdev, __virtio_cread_many(vdev, offset, buf, len, 1); } +static inline u8 virtio_cread8(struct virtio_device *vdev, unsigned int offset) +{ + u8 ret; + vdev->config->get(vdev, offset, &ret, sizeof(ret)); + return ret; +} + static inline void virtio_cwrite8(struct virtio_device *vdev, unsigned int offset, u8 val) { -- cgit v1.2.3 From 012665391dfe12bf8a88d1000e627be012c39dbf Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Wed, 1 Apr 2015 13:31:20 +1030 Subject: virtio: drop a useless config read "virtio: core support for config generation" fixed reading up 64 bit values, adding generation checks for such reads. By mistake, it left an explicit get call in place as well. the result is that the value is read twice, the first result is discarded. Not a big deal since this only happens with virtio blk and only on boot ATM, so performance isn't affected, but let's clean it up. Signed-off-by: Michael S. Tsirkin Reviewed-by: Cornelia Huck Signed-off-by: Rusty Russell --- include/linux/virtio_config.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux/virtio_config.h') diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 22d33034b578..1e306f727edc 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -373,7 +373,6 @@ static inline u64 virtio_cread64(struct virtio_device *vdev, unsigned int offset) { u64 ret; - vdev->config->get(vdev, offset, &ret, sizeof(ret)); __virtio_cread_many(vdev, offset, &ret, 1, sizeof(ret)); return virtio64_to_cpu(vdev, (__force __virtio64)ret); } -- cgit v1.2.3 From cf561f0d2eb74574ad9985a2feab134267a9d298 Mon Sep 17 00:00:00 2001 From: Greg Kurz Date: Fri, 24 Apr 2015 14:24:27 +0200 Subject: virtio: introduce virtio_is_little_endian() helper Signed-off-by: Greg Kurz Signed-off-by: Michael S. Tsirkin Acked-by: Cornelia Huck Reviewed-by: David Gibson --- include/linux/virtio_config.h | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) (limited to 'include/linux/virtio_config.h') diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 1e306f727edc..170947eb11b5 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. */ -- cgit v1.2.3 From 7d82410950aa74adccf035c332e409af2bb93e92 Mon Sep 17 00:00:00 2001 From: Greg Kurz Date: Fri, 24 Apr 2015 14:26:24 +0200 Subject: 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 Signed-off-by: Michael S. Tsirkin Reviewed-by: Cornelia Huck Reviewed-by: David Gibson --- drivers/net/macvtap.c | 3 ++- drivers/net/tun.c | 3 ++- drivers/vhost/vhost.h | 3 ++- include/linux/virtio_byteorder.h | 24 ++++++++++++++---------- include/linux/virtio_config.h | 3 ++- include/linux/vringh.h | 3 ++- 6 files changed, 24 insertions(+), 15 deletions(-) (limited to 'include/linux/virtio_config.h') diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 4fdb88102082..072ccbaf7c45 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 301e87c89a9f..b210139bef8f 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 6a499603d856..a4fa33a79bf2 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 51865d05b267..ce63a2c3a612 100644 --- a/include/linux/virtio_byteorder.h +++ b/include/linux/virtio_byteorder.h @@ -3,17 +3,21 @@ #include #include -/* - * 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 170947eb11b5..e5ce8ab0b8b0 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 3ed62efc2bc5..bc6c28d04263 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) -- cgit v1.2.3