motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-08 10:13:56 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

xen: add grant table interface for XenDevice-s

Browse source 
The legacy PV backend infrastructure provides functions to map, unmap and
copy pages granted by frontends. Similar functionality will be required
by XenDevice implementations so this patch adds the necessary support.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Anthony Perard <anthony.perard@citrix.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
This commit is contained in:
Paul Durrant 2019-01-08 14:48:51 +00:00 • committed by Anthony PERARD
parent 82a29e3048
commit 4b34b5b140
2 changed files with 171 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

146
hw/xen/xen-bus.c
View file

@ -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);