Commit c02d7030 authored by Greg Kurz's avatar Greg Kurz Committed by Michael S. Tsirkin
Browse files

virtio: move bi-endian target support to a single location 



Paolo's recent cpu.h cleanups broke legacy virtio for ppc64 LE guests (and
arm BE guests as well, even if I have not verified that). Especially, commit
"33c11879 qemu-common: push cpu.h inclusion out of qemu-common.h" has
the side-effect of silently hiding the TARGET_IS_BIENDIAN macro from the
virtio memory accessors, and thus fully disabling support of endian changing
targets.

To be sure this cannot happen again, let's gather all the bi-endian bits
where they belong in include/hw/virtio/virtio-access.h.

The changes in hw/virtio/vhost.c are safe because vhost_needs_vring_endian()
is not called on a hot path and non bi-endian targets will return false
anyway.

While here, also rename TARGET_IS_BIENDIAN to be more precise: it is only for
legacy virtio and bi-endian guests.

Signed-off-by: default avatarGreg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Acked-by: default avatarCédric Le Goater <clg@kaod.org>
Reviewed-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 9f318f8f

hw/virtio/vhost.c

+0 −4
Original line number Diff line number Diff line
@@ -767,15 +767,11 @@ static inline bool vhost_needs_vring_endian(VirtIODevice *vdev) 
    if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {

        return false;

    }

#ifdef TARGET_IS_BIENDIAN

#ifdef HOST_WORDS_BIGENDIAN

    return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_LITTLE;

#else

    return vdev->device_endian == VIRTIO_DEVICE_ENDIAN_BIG;

#endif

#else

    return false;

#endif

}



static int vhost_virtqueue_set_vring_endian_legacy(struct vhost_dev *dev,

include/hw/virtio/virtio-access.h

+5 −1
Original line number Diff line number Diff line
@@ -17,9 +17,13 @@ 
#include "hw/virtio/virtio.h"

#include "exec/address-spaces.h"



#if defined(TARGET_PPC64) || defined(TARGET_ARM)

#define LEGACY_VIRTIO_IS_BIENDIAN 1

#endif



static inline bool virtio_access_is_big_endian(VirtIODevice *vdev)

{

#if defined(TARGET_IS_BIENDIAN)

#if defined(LEGACY_VIRTIO_IS_BIENDIAN)

    return virtio_is_big_endian(vdev);

#elif defined(TARGET_WORDS_BIGENDIAN)

    if (virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {

target-arm/cpu.h

+0 −2
Original line number Diff line number Diff line
@@ -29,8 +29,6 @@ 
#  define TARGET_LONG_BITS 32

#endif



#define TARGET_IS_BIENDIAN 1



#define CPUArchState struct CPUARMState



#include "qemu-common.h"

target-ppc/cpu.h

+0 −2
Original line number Diff line number Diff line
@@ -28,8 +28,6 @@ 
#define TARGET_LONG_BITS 64

#define TARGET_PAGE_BITS 12



#define TARGET_IS_BIENDIAN 1



/* Note that the official physical address space bits is 62-M where M

   is implementation dependent.  I've not looked up M for the set of

   cpus we emulate at the system level.  */