With xen-shim, allocate_xenballooned_pages() only allocates a
place-holder page (pfn 0) expecting a subsequent map_grant_ref to fix
it up.
However, this means that, until the grant operation
(GNTTABOP_map_grant_ref) provides a valid page, we cannot set
PagePrivate or save any state.
This patch elides the setting of that state if xen_shim_domain(). In
addition, gnttab_map_refs() now fills in the appropriate page returned
from the grant operation.
Signed-off-by: Joao Martins <joao.m.martins@xxxxxxxxxx>
---
drivers/xen/grant-table.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
index 7ea6fb6a2e5d..ab05b70d98bb 100644
--- a/drivers/xen/grant-table.c
+++ b/drivers/xen/grant-table.c
@@ -804,7 +804,7 @@ int gnttab_alloc_pages(int nr_pages, struct page **pages)
int ret;
ret = alloc_xenballooned_pages(nr_pages, pages);
- if (ret < 0)
+ if (ret < 0 || xen_shim_domain())
return ret;
ret = gnttab_pages_set_private(nr_pages, pages);
@@ -1045,6 +1045,11 @@ int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
{
struct xen_page_foreign *foreign;
+ if (xen_shim_domain()) {
+ pages[i] = virt_to_page(map_ops[i].host_addr);
+ continue;
+ }
+
SetPageForeign(pages[i]);
foreign = xen_page_foreign(pages[i]);
foreign->domid = map_ops[i].dom;
@@ -1085,8 +1090,10 @@ int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
if (ret)
return ret;
- for (i = 0; i < count; i++)
- ClearPageForeign(pages[i]);
+ for (i = 0; i < count; i++) {
+ if (!xen_shim_domain())
+ ClearPageForeign(pages[i]);
+ }
return clear_foreign_p2m_mapping(unmap_ops, kunmap_ops, pages, count);
}
@@ -1113,7 +1120,7 @@ static void __gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item)
int pc;
for (pc = 0; pc < item->count; pc++) {
- if (page_count(item->pages[pc]) > 1) {
+ if (page_count(item->pages[pc]) > 1 && !xen_shim_domain()) {
unsigned long delay = GNTTAB_UNMAP_REFS_DELAY * (item->age + 1);
schedule_delayed_work(&item->gnttab_work,
msecs_to_jiffies(delay));
--
2.11.0
