similar to: [PATCH v6 29/46] vhost: add memory access wrappers

Add guest memory access wrappers to handle virtio endianness conversions. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: Jason Wang <jasowang at redhat.com> --- drivers/vhost/vhost.h | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index c624b09..1f321fd 100644 ---

Add guest memory access wrappers to handle virtio endianness conversions. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: Jason Wang <jasowang at redhat.com> --- drivers/vhost/vhost.h | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index c624b09..1f321fd 100644 ---

Add guest memory access wrappers to handle virtio endianness conversions. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/vhost/vhost.h | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index c624b09..1f321fd 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -176,4 +176,35 @@

Add guest memory access wrappers to handle virtio endianness conversions. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/vhost/vhost.h | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index c624b09..1f321fd 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -176,4 +176,35 @@

Add guest memory access wrappers to handle virtio endianness conversions. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: Jason Wang <jasowang at redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck at de.ibm.com> --- drivers/vhost/vhost.h | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/vhost/vhost.h

Add guest memory access wrappers to handle virtio endianness conversions. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> Reviewed-by: Jason Wang <jasowang at redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck at de.ibm.com> --- drivers/vhost/vhost.h | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/vhost/vhost.h

Hi, This patchset allows vhost_net to be used with legacy virtio when guest and host have a different endianness. It is based on previous work by C?dric Le Goater: https://www.mail-archive.com/kvm-ppc at vger.kernel.org/msg09848.html As suggested by MST: - the API now asks for a specific format (big endian) instead of the hint whether byteswap is needed or not (patch 1) - rebased on top of

Hi, This patchset allows vhost_net to be used with legacy virtio when guest and host have a different endianness. It is based on previous work by C?dric Le Goater: https://www.mail-archive.com/kvm-ppc at vger.kernel.org/msg09848.html As suggested by MST: - the API now asks for a specific format (big endian) instead of the hint whether byteswap is needed or not (patch 1) - rebased on top of

Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/vhost/vhost.h | 33 ++++++++++++++++++++++++++++++++- 1 file changed, 32 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 3eda654..b9032e8 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -174,6 +174,37 @@ enum { static inline int vhost_has_feature(struct

Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/vhost/vhost.h | 33 ++++++++++++++++++++++++++++++++- 1 file changed, 32 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 3eda654..b9032e8 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -174,6 +174,37 @@ enum { static inline int vhost_has_feature(struct

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. It is compatible with modern virtio and can be fully compiled out through kernel config. FWIW, I could flawlessly kexec/reboot guests from ppc64 to ppc64le and back. I could also migrate from a ppc64 to a ppc64le host and back. No regressions on x86 as expected. My experimental QEMU tree

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. It is compatible with modern virtio and can be fully compiled out through kernel config. FWIW, I could flawlessly kexec/reboot guests from ppc64 to ppc64le and back. I could also migrate from a ppc64 to a ppc64le host and back. No regressions on x86 as expected. My experimental QEMU tree

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. It is a complete rework of my initial post. Patches 1 to 5 are preliminary work: we move the endianness check out of all memory accessors to separate functions. Patch 6 changes the semantics of the accessors so that they have explicit big endian support. Patch 7 brings the cross-endian

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. It is a complete rework of my initial post. Patches 1 to 5 are preliminary work: we move the endianness check out of all memory accessors to separate functions. Patch 6 changes the semantics of the accessors so that they have explicit big endian support. Patch 7 brings the cross-endian

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. Patches 1-6 remain the same as the previous post. Patch 7 was heavily changed according to MST's comments. --- Greg Kurz (7): virtio: introduce virtio_is_little_endian() helper tun: add tun_is_little_endian() helper macvtap: introduce macvtap_is_little_endian()

Hi, This patchset allows vhost to be used with legacy virtio when guest and host have a different endianness. Patches 1-6 remain the same as the previous post. Patch 7 was heavily changed according to MST's comments. --- Greg Kurz (7): virtio: introduce virtio_is_little_endian() helper tun: add tun_is_little_endian() helper macvtap: introduce macvtap_is_little_endian()

Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/vhost/vhost.h | 33 ++++++++++++++++++++++++++++++++- 1 file changed, 32 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 3eda654..b9032e8 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -174,6 +174,37 @@ enum { static inline int vhost_has_feature(struct

Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/vhost/vhost.h | 33 ++++++++++++++++++++++++++++++++- 1 file changed, 32 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index 3eda654..b9032e8 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -174,6 +174,37 @@ enum { static inline int vhost_has_feature(struct

Signed-off-by: Greg Kurz <gkurz at linux.vnet.ibm.com> --- drivers/vhost/vhost.h | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) Michael, The vhost_is_little_endian() helper adds unconditionnal overhead to fixed endian architectures: that is all architectures except arm and ppc64. This was addressed in QEMU with a TARGET_IS_BIENDIAN macro. Please give an

Signed-off-by: Greg Kurz <gkurz at linux.vnet.ibm.com> --- drivers/vhost/vhost.h | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) Michael, The vhost_is_little_endian() helper adds unconditionnal overhead to fixed endian architectures: that is all architectures except arm and ppc64. This was addressed in QEMU with a TARGET_IS_BIENDIAN macro. Please give an