From b0e5d90ebc3edb5cfc1d5d33dd3334482dee6d46 Mon Sep 17 00:00:00 2001 From: Cornelia Huck Date: Mon, 26 Jan 2015 17:26:42 +0100 Subject: dataplane: endianness-aware accesses The vring.c code currently assumes that guest and host endianness match, which is not true for a number of cases: - emulating targets with a different endianness than the host - bi-endian targets, where the correct endianness depends on the virtio device - upcoming support for the virtio-1 standard mandates little-endian accesses even for big-endian targets and hosts Make sure to use accessors that depend on the virtio device. Note that dataplane now needs to be built per-target. Cc: Stefan Hajnoczi Cc: Paolo Bonzini Cc: Fam Zheng Reviewed-by: David Gibson Tested-by: David Gibson Signed-off-by: Cornelia Huck Reviewed-by: Stefan Hajnoczi Message-id: 1422289602-17874-2-git-send-email-cornelia.huck@de.ibm.com Signed-off-by: Stefan Hajnoczi --- include/hw/virtio/dataplane/vring-accessors.h | 75 +++++++++++++++++++++++++++ include/hw/virtio/dataplane/vring.h | 14 +---- 2 files changed, 77 insertions(+), 12 deletions(-) create mode 100644 include/hw/virtio/dataplane/vring-accessors.h (limited to 'include') diff --git a/include/hw/virtio/dataplane/vring-accessors.h b/include/hw/virtio/dataplane/vring-accessors.h new file mode 100644 index 0000000000..b508b87900 --- /dev/null +++ b/include/hw/virtio/dataplane/vring-accessors.h @@ -0,0 +1,75 @@ +#ifndef VRING_ACCESSORS_H +#define VRING_ACCESSORS_H + +#include "hw/virtio/virtio_ring.h" +#include "hw/virtio/virtio.h" +#include "hw/virtio/virtio-access.h" + +static inline uint16_t vring_get_used_idx(VirtIODevice *vdev, Vring *vring) +{ + return virtio_tswap16(vdev, vring->vr.used->idx); +} + +static inline void vring_set_used_idx(VirtIODevice *vdev, Vring *vring, + uint16_t idx) +{ + vring->vr.used->idx = virtio_tswap16(vdev, idx); +} + +static inline uint16_t vring_get_avail_idx(VirtIODevice *vdev, Vring *vring) +{ + return virtio_tswap16(vdev, vring->vr.avail->idx); +} + +static inline uint16_t vring_get_avail_ring(VirtIODevice *vdev, Vring *vring, + int i) +{ + return virtio_tswap16(vdev, vring->vr.avail->ring[i]); +} + +static inline void vring_set_used_ring_id(VirtIODevice *vdev, Vring *vring, + int i, uint32_t id) +{ + vring->vr.used->ring[i].id = virtio_tswap32(vdev, id); +} + +static inline void vring_set_used_ring_len(VirtIODevice *vdev, Vring *vring, + int i, uint32_t len) +{ + vring->vr.used->ring[i].len = virtio_tswap32(vdev, len); +} + +static inline uint16_t vring_get_used_flags(VirtIODevice *vdev, Vring *vring) +{ + return virtio_tswap16(vdev, vring->vr.used->flags); +} + +static inline uint16_t vring_get_avail_flags(VirtIODevice *vdev, Vring *vring) +{ + return virtio_tswap16(vdev, vring->vr.avail->flags); +} + +static inline void vring_set_used_flags(VirtIODevice *vdev, Vring *vring, + uint16_t flags) +{ + vring->vr.used->flags |= virtio_tswap16(vdev, flags); +} + +static inline void vring_clear_used_flags(VirtIODevice *vdev, Vring *vring, + uint16_t flags) +{ + vring->vr.used->flags &= virtio_tswap16(vdev, ~flags); +} + +static inline unsigned int vring_get_num(Vring *vring) +{ + return vring->vr.num; +} + +/* Are there more descriptors available? */ +static inline bool vring_more_avail(VirtIODevice *vdev, Vring *vring) +{ + return vring_get_avail_idx(vdev, vring) != vring->last_avail_idx; +} + +#endif diff --git a/include/hw/virtio/dataplane/vring.h b/include/hw/virtio/dataplane/vring.h index d3e086aefc..e42c0fc9cc 100644 --- a/include/hw/virtio/dataplane/vring.h +++ b/include/hw/virtio/dataplane/vring.h @@ -31,17 +31,6 @@ typedef struct { bool broken; /* was there a fatal error? */ } Vring; -static inline unsigned int vring_get_num(Vring *vring) -{ - return vring->vr.num; -} - -/* Are there more descriptors available? */ -static inline bool vring_more_avail(Vring *vring) -{ - return vring->vr.avail->idx != vring->last_avail_idx; -} - /* Fail future vring_pop() and vring_push() calls until reset */ static inline void vring_set_broken(Vring *vring) { @@ -54,6 +43,7 @@ void vring_disable_notification(VirtIODevice *vdev, Vring *vring); bool vring_enable_notification(VirtIODevice *vdev, Vring *vring); bool vring_should_notify(VirtIODevice *vdev, Vring *vring); int vring_pop(VirtIODevice *vdev, Vring *vring, VirtQueueElement *elem); -void vring_push(Vring *vring, VirtQueueElement *elem, int len); +void vring_push(VirtIODevice *vdev, Vring *vring, VirtQueueElement *elem, + int len); #endif /* VRING_H */ -- cgit v1.2.3