diff --git a/hw/xen/xen-bus.c b/hw/xen/xen-bus.c index 5e19592190..faa9fd3577 100644 --- a/hw/xen/xen-bus.c +++ b/hw/xen/xen-bus.c @@ -485,6 +485,138 @@ static void xen_device_frontend_destroy(XenDevice *xendev) } } +void xen_device_set_max_grant_refs(XenDevice *xendev, unsigned int nr_refs, + Error **errp) +{ + if (xengnttab_set_max_grants(xendev->xgth, nr_refs)) { + error_setg_errno(errp, errno, "xengnttab_set_max_grants failed"); + } +} + +void *xen_device_map_grant_refs(XenDevice *xendev, uint32_t *refs, + unsigned int nr_refs, int prot, + Error **errp) +{ + void *map = xengnttab_map_domain_grant_refs(xendev->xgth, nr_refs, + xendev->frontend_id, refs, + prot); + + if (!map) { + error_setg_errno(errp, errno, + "xengnttab_map_domain_grant_refs failed"); + } + + return map; +} + +void xen_device_unmap_grant_refs(XenDevice *xendev, void *map, + unsigned int nr_refs, Error **errp) +{ + if (xengnttab_unmap(xendev->xgth, map, nr_refs)) { + error_setg_errno(errp, errno, "xengnttab_unmap failed"); + } +} + +static void compat_copy_grant_refs(XenDevice *xendev, bool to_domain, + XenDeviceGrantCopySegment segs[], + unsigned int nr_segs, Error **errp) +{ + uint32_t *refs = g_new(uint32_t, nr_segs); + int prot = to_domain ? PROT_WRITE : PROT_READ; + void *map; + unsigned int i; + + for (i = 0; i < nr_segs; i++) { + XenDeviceGrantCopySegment *seg = &segs[i]; + + refs[i] = to_domain ? seg->dest.foreign.ref : + seg->source.foreign.ref; + } + + map = xengnttab_map_domain_grant_refs(xendev->xgth, nr_segs, + xendev->frontend_id, refs, + prot); + if (!map) { + error_setg_errno(errp, errno, + "xengnttab_map_domain_grant_refs failed"); + goto done; + } + + for (i = 0; i < nr_segs; i++) { + XenDeviceGrantCopySegment *seg = &segs[i]; + void *page = map + (i * XC_PAGE_SIZE); + + if (to_domain) { + memcpy(page + seg->dest.foreign.offset, seg->source.virt, + seg->len); + } else { + memcpy(seg->dest.virt, page + seg->source.foreign.offset, + seg->len); + } + } + + if (xengnttab_unmap(xendev->xgth, map, nr_segs)) { + error_setg_errno(errp, errno, "xengnttab_unmap failed"); + } + +done: + g_free(refs); +} + +void xen_device_copy_grant_refs(XenDevice *xendev, bool to_domain, + XenDeviceGrantCopySegment segs[], + unsigned int nr_segs, Error **errp) +{ + xengnttab_grant_copy_segment_t *xengnttab_segs; + unsigned int i; + + if (!xendev->feature_grant_copy) { + compat_copy_grant_refs(xendev, to_domain, segs, nr_segs, errp); + return; + } + + xengnttab_segs = g_new0(xengnttab_grant_copy_segment_t, nr_segs); + + for (i = 0; i < nr_segs; i++) { + XenDeviceGrantCopySegment *seg = &segs[i]; + xengnttab_grant_copy_segment_t *xengnttab_seg = &xengnttab_segs[i]; + + if (to_domain) { + xengnttab_seg->flags = GNTCOPY_dest_gref; + xengnttab_seg->dest.foreign.domid = xendev->frontend_id; + xengnttab_seg->dest.foreign.ref = seg->dest.foreign.ref; + xengnttab_seg->dest.foreign.offset = seg->dest.foreign.offset; + xengnttab_seg->source.virt = seg->source.virt; + } else { + xengnttab_seg->flags = GNTCOPY_source_gref; + xengnttab_seg->source.foreign.domid = xendev->frontend_id; + xengnttab_seg->source.foreign.ref = seg->source.foreign.ref; + xengnttab_seg->source.foreign.offset = + seg->source.foreign.offset; + xengnttab_seg->dest.virt = seg->dest.virt; + } + + xengnttab_seg->len = seg->len; + } + + if (xengnttab_grant_copy(xendev->xgth, nr_segs, xengnttab_segs)) { + error_setg_errno(errp, errno, "xengnttab_grant_copy failed"); + goto done; + } + + for (i = 0; i < nr_segs; i++) { + xengnttab_grant_copy_segment_t *xengnttab_seg = &xengnttab_segs[i]; + + if (xengnttab_seg->status != GNTST_okay) { + error_setg(errp, "xengnttab_grant_copy seg[%u] failed", i); + break; + } + } + +done: + g_free(xengnttab_segs); +} + static void xen_device_unrealize(DeviceState *dev, Error **errp) { XenDevice *xendev = XEN_DEVICE(dev); @@ -509,6 +641,11 @@ static void xen_device_unrealize(DeviceState *dev, Error **errp) xen_device_frontend_destroy(xendev); xen_device_backend_destroy(xendev); + if (xendev->xgth) { + xengnttab_close(xendev->xgth); + xendev->xgth = NULL; + } + g_free(xendev->name); xendev->name = NULL; } @@ -551,6 +688,15 @@ static void xen_device_realize(DeviceState *dev, Error **errp) trace_xen_device_realize(type, xendev->name); + xendev->xgth = xengnttab_open(NULL, 0); + if (!xendev->xgth) { + error_setg_errno(errp, errno, "failed xengnttab_open"); + goto unrealize; + } + + xendev->feature_grant_copy = + (xengnttab_grant_copy(xendev->xgth, 0, NULL) == 0); + xen_device_backend_create(xendev, &local_err); if (local_err) { error_propagate(errp, local_err); diff --git a/include/hw/xen/xen-bus.h b/include/hw/xen/xen-bus.h index df73674fcd..63a09b67ee 100644 --- a/include/hw/xen/xen-bus.h +++ b/include/hw/xen/xen-bus.h @@ -24,6 +24,8 @@ typedef struct XenDevice { enum xenbus_state backend_state, frontend_state; Notifier exit; XenWatch *frontend_state_watch; + xengnttab_handle *xgth; + bool feature_grant_copy; } XenDevice; typedef char *(*XenDeviceGetName)(XenDevice *xendev, Error **errp); @@ -79,4 +81,27 @@ void xen_device_backend_set_state(XenDevice *xendev, enum xenbus_state state); enum xenbus_state xen_device_backend_get_state(XenDevice *xendev); +void xen_device_set_max_grant_refs(XenDevice *xendev, unsigned int nr_refs, + Error **errp); +void *xen_device_map_grant_refs(XenDevice *xendev, uint32_t *refs, + unsigned int nr_refs, int prot, + Error **errp); +void xen_device_unmap_grant_refs(XenDevice *xendev, void *map, + unsigned int nr_refs, Error **errp); + +typedef struct XenDeviceGrantCopySegment { + union { + void *virt; + struct { + uint32_t ref; + off_t offset; + } foreign; + } source, dest; + size_t len; +} XenDeviceGrantCopySegment; + +void xen_device_copy_grant_refs(XenDevice *xendev, bool to_domain, + XenDeviceGrantCopySegment segs[], + unsigned int nr_segs, Error **errp); + #endif /* HW_XEN_BUS_H */